A System of Pyrotechny - Comprehending the theory and practice, with the application - of chemistry; designed for exhibition and for war.

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Title: A System of Pyrotechny - Comprehending the theory and practice, with the application - of chemistry; designed for exhibition and for war.
Author: Cutbush, James
Language: English
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SYSTEM OF PYROTECHNY,

COMPREHENDING THE THEORY AND PRACTICE, WITH THE
APPLICATION OF CHEMISTRY;

DESIGNED FOR EXHIBITION AND FOR WAR.

_IN FOUR PARTS_:

CONTAINING AN ACCOUNT OF THE SUBSTANCES USED IN FIRE-WORKS;
THE INSTRUMENTS, UTENSILS, AND MANIPULATIONS; FIRE-WORKS
FOR EXHIBITION; AND MILITARY PYROTECHNY.

ADAPTED TO THE

MILITARY AND NAVAL OFFICER, THE MAN OF SCIENCE
AND ARTIFICER.

_BY JAMES CUTBUSH, A. S. U. S. A._

LATE ACTING PROFESSOR OF CHEMISTRY AND MINERALOGY, IN THE UNITED
STATES' MILITARY ACADEMY--MEMBER OF THE AMERICAN PHILOSOPHICAL
SOCIETY--CORRESPONDING MEMBER OF THE COLUMBIAN INSTITUTE--MEMBER
OF THE LINNÆAN AND AGRICULTURAL SOCIETIES OF PHILADELPHIA--LATE
PRESIDENT OF THE COLUMBIAN CHEMICAL SOCIETY, AND VICE-PRESIDENT OF
THE SOCIETY FOR THE PROMOTION OF A RATIONAL SYSTEM OF EDUCATION,
&C. &C. &C.

PHILADELPHIA:
PUBLISHED BY CLARA F. CUTBUSH.
1825.

EASTERN DISTRICT OF PENNSYLVANIA, to wit:

BE IT REMEMBERED, that on the ninth day of February, in the
forty-ninth year of the independence of the United States of America,
A. D. 1825, CLARA F. CUTBUSH, of the said district, hath deposited
in this office the title of a book, the right whereof she claims as
proprietor, in the words following, to wit:

_A System of Pyrotechny, comprehending the Theory and Practice,
with the application of Chemistry; designed for Exhibition and
for War. In four parts: containing an account of the Substances
used in Fire-Works; the Instruments, Utensils, and Manipulations;
Fire-Works for Exhibition; and Military Pyrotechny. Adapted to the
Military and Naval Officer, the Man of Science, and Artificer. By
James Cutbush, A. S. U. S. A. late Acting Professor of Chemistry
and Mineralogy in the United States' Military Academy--Member
of the American Philosophical Society--Corresponding Member of
the Columbian Institute--Member of the Linnæan and Agricultural
Societies of Philadelphia--late President of the Columbian Chemical
Society, and Vice-President of the Society for the Promotion of a
Rational System of Education, &c. &c. &c._

In conformity to the act of the congress of the United States,
intituled "An act for the encouragement of learning, by securing the
copies of maps, charts, and books, to the authors and proprietors of
such copies, during the times therein mentioned."--And also to the
act, entitled, "An act supplementary to an act, entitled, "An act
for the encouragement of learning, by securing the copies of maps,
charts, and books, to the authors and proprietors of such copies
during the times therein mentioned," and extending the benefits
thereof to the arts of designing, engraving, and etching historical
and other prints."

D. CALDWELL,

_Clerk of the Eastern District of Pennsylvania_.

_To the Corps of Cadets, of the United States' Military Academy, West
Point_;

GENTLEMEN,

To you, a scientific and distinguished Corps, this work on Pyrotechny
is respectfully dedicated. Your liberal subscription first encouraged
me to undertake its publication; for which, accept my grateful thanks.

CLARA F. CUTBUSH.

ADVERTISEMENT.

In submitting the present work to the public, it may be proper to
state some of the difficulties, under which it has been published,
and to bespeak an indulgent allowance for any imperfections, which
may be observed in the style or arrangement. As a posthumous work, it
has been deprived of those final improvements and emendations, which
are generally made by Authors, while their works are in progress
of publication. While, however, the work has laboured under these
disadvantages, the publisher has felt it her duty to make every
arrangement, to supply, as far as possible, the want of the author's
personal superintendence of the publication. This course was due to
the scientific reputation of her late husband, as well as to the
numerous and generous patrons of the work.

_Philadelphia, April, 1825._

TABLE OF CONTENTS.

PART I.

CHAPTER I.
Page.
Pyrotechny in General, 1
Sec. i. Definition of Pyrotechny, ib.
ii. General Theory of Pyrotechny, ib.
iii. Remarks on the Nature of Particular Compositions, 9
iv. Of Illuminations, 23
v. Of some of the Feats or Performances by Fire, 26

CHAPTER II.

Of the Substances used in the Formation of Fire-works, 48
Sec. i. Of Nitrate of Potassa, or Saltpetre, ib.
ii. Of Nitrate of Soda, 73
iii. Of Chlorate of Potassa, 74
iv. Of Sulphur, 78
v. Of Phosphorus, 84
vi. Of Charcoal, 87
vii. Of Gunpowder, 97
viii. Of Lampblack, 144
ix. Of Soot, 145
x. Of Turpentine, Rosin, and Pitch, 146
xi. Of Common Coal, or Pitcoal, 149
xii. Of Naphtha, Petroleum, and Asphaltum, 153
xiii. Of Oil of Spike, 156
xiv. Of Amber, ib.
xv. Of Camphor, 157
xvi. Of Gum Benzoin, and Benzoic Acid, 161
xvii. Of Storax Calamite, 162
xviii. Of Essential Oils, 163
xix. Of Mastich, ib.
xx. Of Copal, 164
xxi. Of Myrrh, ib.
xxii. Of Sugar, 165
xxiii. Of Sal Prunelle, 167
xxiv. Of Alcohol, 168
xxv. Of Fulminating Mercury, 171
xxvi. Of Fulminating Silver, 173
xxvii. Of Fulminating Gold, 175
xxviii. Of Fulminating Platinum, 176
xxix. Of Detonating Powder from Indigo, 177
xxx. Of the Fulminating Compound, called Iodide of Azote, ib.
xxxi. Of Detonating Oil, or Chloride of Azote, 179
xxxii. Of Pyrophorus, 180
xxxiii. Of Sal Ammoniac, 184
xxxiv. Of Corrosive Sublimate, 186
xxxv. Of Orpiment, 187
xxxvi. Of Antimony, 188
xxxvii. Of Carbonate of Potassa, 189
xxxviii. Of Wood Ashes, 192
xxxix. Of Clay, 193
xl. Of Quicklime, 194
xli. Of Lapis Calaminaris, 195
xlii. Of Zinc, 196
xliii. Of Brass, 197
xliv. Of Bronze, 198
xlv. Of Mosaic Gold, 200
xlvi. Of Iron and Steel, 201
xlvii. Of Glass, 210
xlviii. Of Glue and Isinglass, 214
xlix. Of Wood, 216
l. Of Linseed Oil, 218
li. Of Gum Arabic and Gum Tragacanth, 219
lii. Of Cotton, ib.
liii. Of Bone and Ivory, 220
liv. Of Galbanum, 221
lv. Of Tow and Hemp, 222
lvi. Of Blue Vitriol, ib.
lvii. Of Nitrate of Copper, 223
lviii. Of Strontia, 224
lix. Of Boracic Acid, 226

PART II.

Instruments, Tools, and Utensils, 228

CHAPTER I.

Of the Laboratory, 228
Sec. i. Of Laboratory Tools and Utensils, ib.
ii. Of Mandrils and Cylinders for forming Cartridges
and Cases, 230
iii. Of Rammers, Charges, and Mallets, 231
iv. Of Utensils necessary for constructing Signal
Rockets, 232
v. Of the rolling or plane Board, 233
vi. Of the Driver for Charging large Rockets, 233
vii. Of Mortars and Pestles, ib.
viii. Of the Choaker or Strangler, ib.
ix. Of the Table and Sack for mealing Gunpowder, 234
x. Of Sieves, ib.
xi. Of the Paper Press, ib.

CHAPTER II.

Preliminary operations in the preparation of fire-works, and
observations on the preservation of Gunpowder, and sundry
manipulations, 235
Sec. i. Of the Workshop, ib.
ii. Of the Magazine, ib.
iii. Of the Driving or Ramming of Sky-rockets, 236
iv. Of the Boring of Rockets, 238
v. Of the Preservation of Steel or Iron filings, 239
vi. Of the Making of Wheels and other Works
incombustible, 240
vii. Of the Formation of Rocket and other Cases, 243
viii. Of Tourbillon cases, 245
ix. Of Balloon Cases, or Paper Shells, ib.
x. Of Cases for Illumination Port-Fires, 246
xi. Of Cases and Moulds for Common Port-Fires, 247
xii. Of Pasteboard, and its Uses, 249
xiii. Of the Pulverization of Substances, 253
xiv. Of Mixtures, ib.

PART III.

Fire-Works in General, 255

CHAPTER I.

Observations on Fire-works, 255

CHAPTER II.

Fire-works for Theatrical Purposes, 262
Sec. i. Of Puffs, or Bouffées, ib.
ii. Of Eruptions, 263
iii. Of the Flames, 264
iv. Of the Fire-rain, ib.
v. Of other Compositions for Fire-rain in Chinese Fire, 265
vi. Of Thunderbolts, (_Foudres_), ib.
vii. Of Dragons and other Monsters, 266
viii. Of Lightning, 267
ix. Of the Artifice of Destruction, ib.
x. Of the Spur-Fire, ib.
xi. Of the Coloured Flame of Alcohol, 269
xii. Of Red Fire, 270

CHAPTER III.

Of Portable Fire-works, 271
Sec. i. Of Exhibitions on Tables, ib.
ii. Of Table Rockets, 272
iii. Of the Transparent Illuminated Table Star, 273
iv. Of Detonating Works, ib.

CHAPTER IV.

Of Scented Fire-works, 283
Sec. i. Of Pastilles, 286
ii. Of Vases of Scent, 288
iii. Remarks on Spontaneous Accension, ib.
iv. Of Torches, and Odoriferous Flambeaux, 289
v. Remarks concerning Odoriferous and Fetid Fire, 290

CHAPTER V.

Of Matches, Leaders, and Touch Paper, 292

CHAPTER VI.

Of the Furniture, or Decorations for Fire-works, 298
Sec. i. Of Serpents, ib.
ii. Of Crackers, 300
iii. Of Single Reports, 301
iv. Of Serpent Stars, ib.
v. Of Whirling Serpents, 302
vi. Of Chinese Flyers, 303
vii. Of Simple Stars, ib.
viii. Of Rolled Stars, 304
ix. Of Cracking Stars, ib.
x. Of Sundry Compositions for Stars, designed for
Various Purposes, ib.
xi. Of the Fire-rain, (filamentous), 309
xii. Of Sparks, ib.
xiii. Of Gold-rain, 310
xiv. Of Rains in General, for Sky-Rockets, &c. 311
xv. Of Rain-Falls and Stars, double and single, ib.
xvi. Of substances which show in Sparks, 312
xvii. Of Italian Roses, or Fixed Stars, 313
xviii. Of Lances of Illumination, white, blue and yellow, 314
xix. Of Slow White-flame Lances, 315
xx. Of Lights, ib.
xxi. Of Lances for Petards, 318
xxii. Of Lances for Service, ib.
xxiii. Of Marrons, ib.
xxiv. Of Shining Marrons, 320
xxv. Of Saucissons, 321
xxvi. Of Fire-Pumps, 322
xxvii. Of the Volcano of Lemery, 323
xxviii. Of the Blue and Green Match for Cyphers, Devices
and Decorations, 324
xxix. Of the Purple or Violet Match, 325
xxx. Of Meteors, ib.

CHAPTER VII.

Of Rockets and their Appendages, 326
Sec. i. Of the Caliber and Proportion of Rockets, ib.
ii. Of the Composition of Sky-Rockets, and Observations
on its Preparation, and on other Subjects
respecting rockets, 329
iii. Of the Heading of Rockets, 334
iv. Of the Decorations for Rockets, and the Manner
of filling their Heads, 335
v. Of the Dimensions, and Poise of Rocket-Sticks, 336
vi. Of the Mode of Discharging Rockets, 337
vii. Of the Appendages, and Combinations of Rockets, 340
viii. Of Swarmers or Small Rockets, 343
ix. Of Scrolls for Sky-Rockets, and of Strung, Tailed,
Drove, and Rolling Stars, 344
x. Of Line-Rockets and their Decorations, 345
xi. Of Signal Sky-Rockets, 347

CHAPTER VIII.

Of Sundry Fire-works, denominated Air-works, 347
Sec. i. Of the Composition, and Mode of Forming large
and small Gerbes, 348
ii. Of Paper Mortars, 349
iii. Of Mortars to throw Aigrettes, &c. 350
iv. Of Making Balloon Fuses, 357
v. Of the Mosaic and Common Tourbillon, 358
vi. Of Mortars for throwing Aigrettes, and the
Manner of Loading and Firing them, 363
vii. Of Making, Loading, and Firing Pots des Brins, 364
viii. Remarks respecting Fire Pots, 365

CHAPTER IX.

Of Particular Compositions, 367
Sec. i. Of Fire-Jets, or Fire-Spouts, ib.
ii. Of Priming and Whitening Cases, and Remarks
concerning Spunk and Touch Paper, 370
iii. Of Chinese Fire, 371
iv. Of Bengal Lights, 377
v. Of Roman Candles, 380
vi. Of Mosaic Simples, 381
vii. Of Mosaic Tourbillons, 382
viii. Of Hydrogen Gas in Fire-works, 383

CHAPTER X.

Of the Manner of fixing and arranging Fire-works in General
for Exhibition, 387
Sec. i. Of the Composition of Wheel-Cases, Standing
and Fixed, 388
ii. Of Single, Vertical, Horizontal, Spiral, and
other Wheels, 391
iii. Of Revolving Suns, 395
iv. Of Fixed Suns, 397
v. Of Fixed Suns with Transparent Faces, 398
vi. Of the Rose-Piece and Sun, 399
vii. Of the Manner of changing a Horizontal to a
Vertical Wheel, and representing a Sun in front, ib.
viii. Of Caprices and Fire-Wands, 400
ix. Of Palm and other Trees, 401
x. Of the Pyramid of Flower Pots, 402
xi. Of the Dodecaedron, 403
xii. Of Cascades of Fire, 404
xiii. Of Chinese Fountains, and Parasols, 405
xiv. Of Wings, or Cross Fire, 406
xv. Of Galleries of Fire, and Batteries of Roman
and Mosaic Candles, ib.
xvi. Of Girandoles, and their Modifications, 407
xvii. Of Cracking Caprices, ib.
xviii. Of the Projected Regulated Piece of Nine Mutations, 408
xix. Of the Pyric or Fire-Piece, 412
xx. Of Sundry Illuminated Figures, 413
xxi. Of the Spiral or Endless Screw, and Waved Fire, 418
xxii. Of the Decoration of Wheels, ib.
xxiii. Of Globes, with their Various Decorations, 419
xxiv. Of the Representation of the Moon and Stars, 421
xxv. Of the Representation of Sundry Figures in Fire, 423
xxvi. Of the Representation of Flat Stars with a large
Body of Fire, 424
xxvii. Of the Single, Double, and Triple Table Wheel, 425
xxviii. Of Decorations, Transparencies, and Illuminations, ib.
xxix. Of Imitative Fire-works, 440

CHAPTER XI.

Of Aquatic Fire-works, 442
Sec. i. Of Water Rockets, 443
ii. Of Pipes of Communication, ib.
iii. Of Horizontal Wheels for Water, 444
iv. Of Water Mines, ib.
v. Of Fire Globes for the Water, 445
vi. Of Odoriferous Water Balloons, 446
vii. Of Water Balloons, 447
viii. Of Water Squibs, 448
ix. Of the Water Fire-Fountain, ib.
x. Of Swans and Ducks, to discharge Rockets in Water, ib.
xi. Of Discharging Rockets under Water, 449
xii. Of the Representation of Neptune in his Chariot, 450
xiii. Of the Representation of a Sea-Fight with small
Ships, and the Preparation of a Fire-Ship, 451

CHAPTER XII.

Of the Arrangement of Fire-works for Exhibition, 452

PART IV.

Military Pyrotechny, 456

CHAPTER I.

Observations in General, 456
Sec. i. Of Cartridges, 462
ii. Of Cannon Cartridges, 467

CHAPTER II.

Of Matches, 471
Sec. i. Of Slow Match, ib.
ii. Of Priming Tubes, 475
iii. Of Quick Matches, 477

CHAPTER III.

Of Port-Fires, 479

CHAPTER IV.

Of Fuses for Shells, Howitzes, and Grenades, 481
Sec. i. Of the Method of Charging the Fuses of Bombs
or Shells, 482
ii. Of Loading Shells, Howitzes, and Grenades, 484
iii. Of Fuses with Dead Light, 485
iv. Of the Dimensions of Fuses, and the Dimensions
and Charge of Bombs, Howitzes, and Grenades, 487

CHAPTER V.

Of Incendiary Fire-works, 490
Sec. i. Of Fire Stone, 491
ii. Of Incendiary Matches, 492
iii. Of Carcasses and Fire Balls, ib.
iv. Of Incendiary Balls, or Fire Balls, to be thrown
from Cannon or by Hand, 497
v. Of Smoke Balls, 499
vi. Of Stink Balls, ib.
vii. Of Poisoned Balls, ib.
viii. Of Red-hot Balls, 499
ix. Of Pitched Tourteaux and Fascines, 500
x. Of Torches, or Flambeaux, 501
xi. Of Powder Bags, 503
xii. Of the Powder Barrel, ib.
xiii. Of the Burning, or Illuminating Barrel, ib.
xiv. Of the Thundering Barrel, 504
xv. Of the Petard, 505
xvi. Of the Stink-Fire Lance, 506
xvii. Of the Combustible Substances used in, and the
Manner of preparing, a Fire-Ship, 507
xviii. Of Infernal Machines, 512
xix. Of the Catamarin, 514
xx. Of the American Turtle, 515
xxi. Of the Torpedo, 521
xxii. Of the Marine Incendiary Kegs, 523
xxiii. Of Sea Lights, 525
xxiv. Of Signal and War-rockets, 526
xxv. Of Sky-Rockets, (_Meurtrières_,) 538
xxvi. Of the Rocket Light-Ball, 539
xxvii. Of the Floating Rocket Carcass, ib.
xxviii. Observations on Rockets, 540
xxix. Of the Succouring Rocket, 544
xxx. Of the Greek Fire, ib.
xxxi. Of Mines and Mining, 550
xxxii. Of the Means of Increasing the Strength of
Gunpowder for Mining, 554
xxxiii. Of Incendiary Bombs, 556
xxxiv. Of Murdering Marrons, 557
xxxv. Of Incendiary Rope, 558
xxxvi. Of Balloons of Grenades, of Bombs, and of
Flints or Stone, 559
xxxvii. Of Spherical Case Shot, ib.
xxxviii. Of the Fire-Rain, according to Casimir Siemienowicz, 560
xxxix. Of the Effect of Mirrors in inflaming Bodies at
a Distance, 562
xl. Of Incendiary and Poisoned Arrows, 566
xli. Of Pyrotechnical Sponge, 570
xlii. Of Extinguishing Flame with Fired Gunpowder, 572
xliii. Of the Inflammable Dart, 574
xliv. Of the Firebrand, ib.
xlv. Of the Fire Flask, 575
xlvi. Of the Trompe-Route, ib.
xlvii. Of Fire-Pots for Ramparts, ib.
xlviii. Of Inflammable Balls, 577
xlix. Of Pauly's Inflammable Powder, ib.
l. Of Extemporaneous Fire, 578
li. Of the Indian White Fire, 580
lii. Of the Pyrophore of Defence, 581

INTRODUCTION.

In presenting this work to the public as a system of Pyrotechny,
which, we have reason to believe, is the only full and connected
system that has appeared, we may be permitted to remark, that, in our
arrangement of the subject, we have appropriated separate heads for
each article.

This plan, of the subject being considered in chapters and sections,
and forming with the divisions of the work, a connected system of
arrangement, enables the reader to have a full view of the whole,
and, at the same time, all the facts in detail belonging to the
chapter, or section under consideration. By referring to the Table
of Contents, this plan will be seen without further comment. The
arrangement of the different articles in this manner, necessarily
comprehends in the onset all the substances, which are employed in
various preparations. In considering this part of our subject, we
have given the chemical characters, or peculiar properties of each
substance respectively; by which a rationale of pyrotechnical effects
may be the better understood, and, consequently, the action of bodies
on each other better illustrated.

In this part we also comprehend the General Theory of Fire-works,
which it may be proper to remark, we have drawn from the known
effects of chemical action; so far, at least, as the laws, of
affinity, which govern such action, are applicable to the subject.
The importance of this inquiry, although having no relation to the
mere manipulations of the artificer, can not be doubted; since a
knowledge of chemistry has already improved the preparation of
gunpowder, and its effects are now known to be owing to the formation
of sundry elastic aeriform fluids. On this head, that of the
application of chemistry to Pyrotechny, we claim so much originality,
as, so far as we know, to have been the first, who applied the
principles of chemistry.

It is not to be expected in every instance, that a rationale of the
decomposition as it occurs, or the order in which it takes place,
can be given with certainty; because, where a variety of substances
enter into the same preparation, which is frequently the case, the
affinities become complicated, and the laws of action for that reason
indeterminate, and frequently anomalous. But, on the contrary, in
a variety of primary operating causes, by which effects analogous
in their nature result, decomposition of course being the same, the
causes are well understood, and the effects are thereby known, and
duly appreciated.

This, for instance, is the case with a mixture of nitrate of potassa,
charcoal, and sulphur, in the proportion necessary to form gunpowder;
for, it is known, that the explosive effects of powder are owing to
the sudden production of a number of gases, which suffer dilatation
by the immense quantity of caloric liberated at the moment of
combustion. Although the production of caloric by the inflammation
of gunpowder is a case, which cannot be explained by the present
received theory of combustion, as we have noticed in that article;
yet we know that it is a fact, and that caloric is generated by the
decomposition of the powder.

If we consider the primary cause of this decomposition, we naturally
inquire into the products of the combustion, and endeavour to
account for the production of the elastic aeriform fluids. We know
that carbon has the property of decomposing nitric acid, and also
nitrate of potassa; for, when it is brought in contact in the state
of ignition with nitre, a deflagration will ensue, and carbonic acid
be formed. The quantity of this acid is in the direct _ratio_ to
the quantity of oxygen required to _saturate_ a given quantity of
carbon; and therefore, by employing certain proportions of nitre and
charcoal, the latter will decompose the former, and by abstracting
its oxygen, on the same principle form carbonic acid, while the
azote, the other constituent of nitric acid, will be set at liberty.
Nor is this all, if we consider the action of sulphur. The sulphur
must unite with one portion of the oxygen to produce sulphurous acid
gas, and also with the potassa of the nitre, and form a sulphuret, a
compound necessary to be formed, before we can explain the production
of sulphuretted hydrogen gas, which results from the decomposition
of water contained in the nitre. There also results, as a product,
sulphate of potassa. In considering these products at large, it would
be necessary to go into detail; and, as we have descanted largely on
its combustion in gunpowder, we accordingly refer the reader to the
article on _Gunpowder_. It will be sufficient, however, to remark,
that the _agent_, and consequently the cause, which produces the
decomposition of nitrate of potassa, is carbon or charcoal. This, by
uniting with the greater part of the oxygen of the nitre, produces,
in a determinate proportion, carbonic acid gas. This gas, therefore,
in conjunction with other gases, formed at the same time, all of
which being expanded, causes what is denominated the _explosive
effect_ of gunpowder.

We have then a primary cause of the decomposition, and most of the
effective force of gunpowder is owing to the carbonic acid; and it
is found, that gunpowder made without sulphur is equally powerful as
that with, since it adds nothing to its power.

Causes, therefore, chemically speaking, operate alike under similar
circumstances. The materials made use of being equally pure, and used
in the same proportion, the effect must necessarily be the same.

It is not only in the instance we have mentioned, but in every other,
in which chemical action ensues, that this doctrine is tenable.
We might, indeed, notice a number of cases of a similar kind; as,
for instance, in the combustion of many incendiary preparations,
as fire-stone, fire-rain, composition for carcasses, light-balls,
and a variety of fire-works of the same kind. If we mix pitch, tar,
tallow, &c. with nitrate of potassa, and burn the mixture, we have
the combined action of two elementary substances, which enter into
the composition of these bodies, namely, carbon and hydrogen. The
products would be carbonic acid gas, and water; because the oxygen of
the nitre would unite with the hydrogen, as well as the carbon. If we
employ sulphur at the same time, another product would be sulphurous
acid gas, and probably sulphuric acid; and if gunpowder be used, as
in the _fire-stone_ composition, then, besides these products, we
would have those of the gunpowder.

As this subject, however interesting to the theoretical pyrotechnist,
cannot be understood without a knowledge of chemistry, it is obvious,
that that science is a powerful aid to pyrotechny. It is unnecessary
to dwell on this head. We may add, nevertheless that, in order to
understand the effect of all mixtures, or compositions made use of,
it is necessary to consider the nature of the substances employed,
and the manner in which chemical action takes place, and consequently
the products, which determine in fact the characteristic property
of each species of fire-work, and the phenomena on which it is
predicated. All products of combustion depend on the substances thus
decomposed, and by knowing the effects, we may readily refer them to
their proper causes.

With respect to _caloric_, it may not be improper to offer some
remarks.[1] The hypothetical element of phlogiston having given
way to the antiphlogistic theory at present received, our ideas
respecting caloric are predicated on facts. Caloric is a term, which
expresses heat, or matter of heat. In pyrotechny, we have merely to
consider it in a free, or uncombined state; but as the subject is
interesting, we purpose to notice it very briefly under the following
heads: viz. its nature; the manner it is set in motion; its tendency
to a state of rest; the changes it produces on bodies; and the
instruments for measuring its intensity.

As to the nature of caloric, different opinions are entertained.
We know the effect of heat: if we touch a substance of a higher
temperature than our bodies, we call it hot, and _vice versa_. The
one is evidently the accession, and the other the abstraction, of
caloric. The latter is merely relative as respects ourselves; for the
effect depends on our feelings, and the sensation of hot or cold is
therefore governed by them.[2] Caloric, however, is considered to
be a substance, composed of inconceivably small particles; but count
Rumford and sir H. Davy are of a contrary opinion, namely, that it
depends upon a peculiar motion and not on a subtle fluid.

As the effect of caloric, according to their view, depends on motion,
the agencies by which this is effected are of the first importance.
That it exists in all bodies in a state of rest, and in a greater or
smaller quantity, and consequently in a relative proportion, is well
known, and on this, the capacities of bodies for caloric is founded.
The capacities of bodies for heat are changed by various means, and
caloric is put in motion; and, according to its quantity, the bodies
may be either cold or hot. When the surrounding bodies become heated,
they receive this caloric thus set free, and, in this view, the
absolute quantity of their heat is increased. This state of rest, to
which caloric is subject, may be destroyed either by an increase or
a diminution of the capacity of a body. If caloric be put in motion
by causes of any kind, which influence the capacities of different
bodies, a theory maintained by Davy, then as the capacity for heat
is changed so is free heat produced. Diminish the capacity of a
body, its excess will of course be given out, and distribute itself
among the surrounding bodies, which become heated; but increase
the capacity, and a different effect ensues. The body absorbs
caloric, by which its capacity is increased, and cold is produced.
Caloric, whether considered a substance, or an attribute, possesses,
nevertheless, this property, that when it is given out, as in the
mixture of sulphuric acid and water, which occupies a less space than
both in a separate state, the sensation of heat follows; and when it
is absorbed, as in the various freezing mixtures, or in a mixture of
snow and common salt, the sensation of cold is excited. The causes,
however, which set caloric in motion, or that produce heat, are such
as combustion, condensation, friction, chemical mixture, and the
like. It is remarkable, that these effects are invariably the same,
and are affected by corresponding affinities. When a piece of iron
is struck with a hammer, the percussion produces a condensation of
the iron, its specific gravity is increased, and the iron finally
becomes ignited. The condensation of air, in the condensing syringe,
will set fire to tinder. The flint and steel produce a condensation;
for the metal, although small, is sent off in scintillations in
the state of ignition. That caloric is contained in bodies in the
state of absolute rest, and is evolved by condensation, there is no
doubt. Gunpowder, by percussion, in contact with pulverized glass, is
inflamed; and it appears very probable, that it also contains caloric
in a state of rest. The experiments of Lavoisier and Laplace, on the
quantity of caloric actually absorbed in nitric acid, and in a latent
state, (noticed in the article on _gunpowder_), are satisfactory.
If caloric is not in that state in nitre, how are we to explain the
sudden transmission or evolution of caloric in fired gunpowder, where
no external agent in any manner can influence the formation, or
disengagement of caloric? Friction or attrition produces heat; and
the distributable excess of caloric, as it is called, although not
satisfactorily accounted for, may arise from a condensation; which,
however, is denied.

The Esquimaux Indians kindle a fire, very expeditiously, in the
following manner: They prepare two pieces of dry wood, and making a
small hole in each, fit into them a little cylindrical piece of wood,
round which a thong is put. Then, by pulling the ends of this thong,
they whirl the cylindrical piece about with such velocity, that the
motion sets the wood on fire, when lighting a little dry moss, which
serves for tinder, they make as large a fire as they please; but as
the little timber they have is drift wood, this fails them in the
winter, and they are then obliged to make use of their lamps for the
supply of their family occasions. _Ellis's Voyage for the Discovery
of a North-West Passage._

Friction is, therefore, one means of producing distributable heat,
which is also exemplified very frequently in the axis of a carriage
wheel; of mill work; in the rubbing of wood, when turned on its axis
in a lathe, by which turners ornament their work with black rings;
rubbing a cord very swiftly backwards and forwards against a post or
tree, or letting it run over a boat, &c. as in the whale fishery;
the motion of two iron plates against each other, pressing them at
the same time, &c. The great object in the construction of machines
is to avoid, or lessen the degree of friction. See Hatchette, Vince,
and Gregory. Count Rumford (Nicholson's Journal, 4th edit. ii, 106),
and professor Pictet (_Essai sur le Feu_, chap. ix.) have made some
valuable experiments on heat evolved by friction.

The sun is one great source of caloric. In whatever mode it produces
it, whether by giving it out from its own substance, by the action
of light on the air that surrounds the globe; by the concentration
of calorific rays by means of the atmosphere, acting as a lens; or
by putting caloric in the distributable state, always pre-existing
in some other, as in a state of rest, are questions, which, in our
present state of knowledge, we are unable to solve. We know the
fact, and that the caloric is of the same nature as that obtained by
combustion.[3]

Combustion is a process by which caloric is put in a distributable
state. The opinion of Stahl and others, that all combustible bodies
contained a certain principle called phlogiston, to which they owed
their combustibility, and that combustion was nothing more than a
separation of this principle, gave rise to the phlogistic or Stahlian
theory, which was afterwards modified by Dr. Priestley. But his
theory is equally untenable. Kirwan's opinion was no less vague,
although he substituted hydrogen for phlogiston.

The Lavoiserian, or antiphlogistic theory overturned the Stahlian.
According to this theory, a combustible in burning unites with
oxygen, and heat and light are given out by the gas, and not from
the combustible. According to a modified theory of the above, by Dr.
Thomson, caloric is evolved by the gas, and light from the burning
body. Without noticing the instances, in which this theory, as a
general one, is insufficient to explain the cause of combustion, or
of the production of heat and light, we will merely remark, that
bodies which support combustion are called supporters, as oxygen gas,
chlorine gas, &c. and those, that undergo this change, are named
combustible bodies.

The products of combustion may be fixed or gaseous, and either
alkalies, oxides, or acids; or, when chlorine is the supporter,
chlorides, &c. A few examples will be sufficient. By the combustion
of metals, iron for instance, we obtain a fixed product, and in
the present case an oxide of iron; by the combustion of antimony
and arsenic, the antimonic and arsenic acids; by the combustion
of charcoal, we have carbonic acid gas, a gaseous product; by
the combustion of potassium or sodium, we obtain a fixed alkali,
depending however on the quantity of oxygen; by the combustion of
sulphur, phosphorus, &c. acids; and when metals are burnt in chlorine
gas, chlorides are produced.

It is evident from facts, that, whatever theory may be assumed,
combustion occasions the production of _free_ caloric, or changes
the _condition_ of caloric, from quiescent to distributable heat.
The conclusions drawn by Mr. Davy and others, appear to have been
predicated on the absorption of the base, and development of caloric,
as in oxygen gas, and the peculiar alteration in bodies implying a
decrease in their capacity; and hence, as regards the products of
combustion, they must necessarily possess a less capacity for heat
than the mean capacity of their constituents.

Whether we regard heat as latent, in the acceptation of the term, as
applied or used by Dr. Black, or quiescent, or in a state of rest, it
is certainly evident, that combustion is a chemical change, and by it
caloric passes from a combined to an uncombined state, and is thus
made sensible, free, or thermometrical heat. Combustion may, as it
certainly does, put quiescent heat in a distributable state; but this
quiescent heat is the same in the present case, of which there can
be no doubt, as latent caloric. The thermometer will only indicate
as much caloric in the air as is in a distributable, or free state;
but, if the same air be employed to supply, or support combustion,
the heat, rendered appreciable by the senses and the thermometer,
will be in the ratio of the decomposition of the oxygen gas of the
atmosphere, and, of course, to the development of free caloric.

Chemical combination, such as occurs by the mixture of fluids, as
alcohol and water, sulphuric acid and water, some of the gases,
as muriatic acid gas with water, &c. evolves heat, and sometimes
sufficient to boil water. In cases of spontaneous combustion, it
would seem, that quiescent heat passes to the state of distributable
heat; for if nitric acid, for instance, contains so large a quantity
of quiescent heat, or fixed heat, as the experiments of Mr.
Lavoisier make it appear, we may readily explain why spontaneous
combustion ensues, when that acid is brought in contact with spirits
of turpentine; because the chemical action of the acid on the carbon
and hydrogen of the turpentine, which takes place, produces at the
same time a corresponding change in the caloric itself, from a
quiescent to a distributable state. If the same data be admissible
with regard to the combination of the nitric acid with potassa, which
we may judge to be the case by the experiments of Lavoisier and
Laplace, (quoted in our article on _Gunpowder_), then, indeed, its
mechanical union with charcoal, and sulphur, although in a common
temperature no combustion ensues, will, at the temperature required
to inflame the mixture, (about 700 degrees according to some),
produce a decomposition altogether chemical; and while new products
are formed, the caloric, necessary also for their generation, passes
from a quiescent to a distributable state; and a portion of it goes
into a new state of combination, also quiescent. We mean that portion
which is necessary for the constitution of gaseous fluids. This
fact is remarkable. By referring to the original state or condition
of the caloric, if we admit that state in the present instance,
(which appears the only mode of accounting for the emanation of free
caloric by the combustion of gunpowder), it is easily perceived, that
chemical changes, besides the usual supporters of combustion being
concerned, as in ordinary cases of combustion, must produce a similar
change in the state of combined or quiescent heat.

Predicating this opinion on the results of the experiments of MM.
Lavoisier and Laplace, and seeing that gunpowder inflames _per se_,
or without the aid of a gaseous supporter, we have no hesitation in
risking it, in the present state of our knowledge concerning heat as
our present belief and conviction. Although there is no satisfactory
theory offered to explain all the instances of spontaneous
combustion, yet it seems reasonable to conclude, that in many cases
at least, that effect may take place by some chemical action,
which, like the instances already quoted, may change quiescent
into distributable heat. We have stated (See _Gunpowder_) some
instances of spontaneous combustion, which have taken place merely
in consequence of the charcoal. Some have attributed the effect to
pyrophorus, and others to the presence of hydrogen in the coal,
which, by absorbing and combining with oxygen and forming water,
sets the caloric of the oxygen gas at liberty, and thus produces
combustion. However this may be, there are other instances, that of
cotton and oil, some kinds of wood, wood-ashes and oils, &c. which
have produced spontaneous combustion.

We will only add, however, that until we can give a better theory,
the effect in these instances may be attributed to chemical action,
and _with it_, the change of caloric in the manner already mentioned.
Chemical action in such cases appears necessary, although mechanical
means, as percussion will produce heat.

Quiescent heat is also put in motion by electricity; but in what
manner it acts, so as to produce that effect, is unknown. It is a
powerful agent in nature, and calculated for important ends, of which
we are ignorant. It is unnecessary to notice opinions concerning it.
All electrics will yield it, such as glass, rosin, &c. and it may
be collected in the usual manner by the prime conductor and Leyden
jar. Galvanism, called also Galvanic electricity, produced by an
arrangement of zinc, and copper plates in a pile, or trough, and
placed in contact with some oxygenizing fluid, has the same effect of
causing quiescent heat to become distributable, and is undoubtedly
the result of chemical action. The peculiar character of this fluid,
the nature of the two opposite poles, &c. have been, and continue
to be, a subject of interest to the philosopher. The _deflagrator_
of professor Hare of Philadelphia is an apparatus well calculated
for many interesting experiments on galvanism. To that gentleman, we
are also indebted for the compound blowpipe, which produces a very
intense heat by the combustion of hydrogen in contact with oxygen
gas. Notwithstanding professor Clark of England has laid claim to the
apparatus, and the use of hydrogen gas in this way, the merit of the
discovery is due to our learned and ingenious countryman.

Since heat is put in motion as a consequence of the increased
capacity of a body, and, by combining with a substance whose capacity
has been increased, becomes by degrees quiescent, according to
the respective capacities of bodies; cold is an effect, which is
occasioned by this change from a free to a combined or quiescent
state. The absorption of heat, necessary for the generation of
cold, if so we may consider it, takes place in every instance,
where that effect is observed. The heat of surrounding bodies, in a
distributable state, is now no longer characterised as such; and the
consequence is, therefore, that that particular sensation, or effect
follows.

Cold may be produced by saline mixtures, the salts for which having
their full quantum of the water of crystallization; and by the
evaporation of fluids, as water, alcohol and ether. In the one
case, that of the freezing mixtures, we have seen, that the effect
is produced by the _absorption_ of heat; and with regard to the
cold produced by fluids, even in _vacuo_, (where the effect is more
instantaneous), the cause is attributable to evaporation; for the
fluid changes from a liquid to an aeriform state, and during this
transition robs the body, with which it was in contact, of a part of
its caloric, and thereby reduces its temperature. Artificial ice is
made on this principle.

The next subject with regard to heat, is the different modes in which
it tends to a state of rest. There are some facts in relation to this
subject worthy of notice; and particularly, that, in the tendency of
caloric to become quiescent, after having been put in motion, bodies
often increase in temperature. This tendency to a state of rest is
effected either by the conducting power of bodies, or radiation.
Heat radiates in all directions, and in quantities, according to
the experiments of Leslie, more or less variable, which depend on
the nature of the radiating surface. Hence that power, which bodies
possess, called the radiating power, varies in different substances.
Thus, the radiating power of lampblack is 100, while gold, silver,
copper, and tin plate are 12, from which it appears that the metals
distribute less heat by radiation. That caloric obeys the same
laws as light, is obvious from Pictet's experiments with concave
mirrors, where the calorific rays move in the same order, the angle
of incidence being equal to the angle of reflection. It is also
refracted; hence the concentration of the solar rays in a focus by
the burning glass. Various experiments have been made with mirrors,
and concave reflectors. The effect of the former in destroying the
fleet before Syracuse, an experiment made by Archimedes, is a fact
well authenticated in history. Concave reflectors have inflamed
gunpowder. This subject, however, is noticed at large, when speaking
of mirrors as an incendiary in war.

That bodies conduct heat, and with different degrees of power, so
that some are called good and others bad conductors, is well known.
This property depends on the quantity of caloric, which a body
receives, before it changes its state. Metals are considered good
conductors, and glass, charcoal, feathers, &c. bad conductors. Hence
bad conductors, as wool, &c. preserve the temperature of the body,
or keep it _warm_ in winter; and snow, for the same reason, prevents
the action of intense cold on the ground. Liquids also conduct heat.
Whether we consider caloric in this case carried, or transported,
as it is more properly defined, the fact may be shown by several
experiments. Ebullition, or boiling, is a phenomenon, which depends
on the increment of temperature; for as water, for instance, receives
caloric, until the thermometer indicates 212 degrees, the boiling
point, mere evaporation ensues; but that temperature, under the
usual pressure of the atmosphere, causes the formation of bubbles at
the bottom of the vessel, as that part receives the degree of heat
necessary for ebullition before any other; and these bubbles, as they
form, rise in succession, and pass off in the state of steam, while
the circumjacent fluid takes its place, and the process continues
till all is boiled away. Water, when it passes off in the state
of steam, which requires a degree of heat equal to 212 degrees of
Fahrenheit, receives also 1000 degrees of non-distributable caloric,
or latent heat; and however singular the fact may appear, the wise
Author of Nature, it seems, has reserved a _store of caloric_, in
this form, ready to be put in requisition, when necessity demands it,
in a distributable shape.

Caloric, when in a state of rest, exists in different proportions,
and although the actual temperature may be the same, yet the quantity
of caloric in a quiescent state may be variable. There are several
experiments, which are adduced to illustrate this fact. It results
from experiment, that bodies receive heat according to their several
capacities for it; hence, when any number of bodies are differently
heated, the caloric, which becomes latent, does not distribute itself
in equal quantities, but in various proportions, according, as we
remarked, to their several capacities. Caloric, therefore, in a
state of rest, is in relative quantities; and as the capacity of
bodies for heat is variable, and relative as to each other, the term
_specific caloric_ has been applied. From these conclusions, we may
readily perceive what is implied by an equality of temperature. That
it merely depends on the state of rest, which caloric necessarily
comes to, and which is relative as respects the capacity of bodies,
and nothing more, is a deduction very plain and obvious. Heat, in a
state of motion, may be said to be progressing to a quiescent state;
and equalization of temperature, although differently understood,
may be considered an equalization of fixed caloric, according to the
relative capacity of bodies, without regarding the equalization,
which takes place of uncombined caloric, as is manifested by
thermometrical instruments. In a word, by considering caloric in this
view, that of tending to a state of rest, and uniting with bodies
according to their respective capacities, we may account for many
phenomena; as, for instance, the quantity of caloric which enters
into ice, and becomes latent, during liquefaction. The quantity of
caloric, in this respect, may be learnt by adding a pound of ice at
32 degrees to a pound of water at 172 degrees. The temperature will
be much below 102 degrees, the arithmetical mean, viz. 32 degrees.
It is evident that the excess of caloric has disappeared; and by
deducting 32 degrees from 172 degrees, 140 degrees remain, which
is the quantity of caloric that enters into a pound of ice during
liquefaction, or the quantity required to raise a pound of water from
32 degrees to 172 degrees. This change of capacity appears to be
absolutely essential to the well being of the universe, as affording
a constant modification of the action of heat and cold, the effects
of which would otherwise be inordinate. If this did not take place,
the whole of a mass of water, which was exposed to a temperature
above the boiling point, would be instantly dissipated in vapour with
explosion. The polar ice, would all instantly dissolve, whenever the
temperature of the circumambient air was above 32 degrees, if it were
not that each particle absorbs a quantity of caloric in its solution,
and thereby generates a degree of cold which arrests and regulates
the progress of the thaw; and the converse of this takes place in
congelation, which is in its turn moderated by the heat developed
in consequence of the diminution of capacity, which takes place in
the water during its transition to a solid state. The reason why
boiling water in the open air never reaches a higher temperature than
212 degrees is evident, if we consider, that the capacity of those
portions of liquid, which are successively resolved into a vapour,
becomes thereby sufficiently augmented to enable them to absorb the
superabundant caloric as fast as it is communicated.

The most obvious effect of caloric on bodies, is the change, which
they undergo when exposed to its action.

That it acts constantly in opposition to the attraction of cohesion
or of aggregation, by which bodies pass from a solid to a fluid,
and from a fluid to an aeriform state, and produces also different
changes in bodies,--are facts that come under our daily observation.

It occasions changes in the bulk of bodies; hence solids, liquids,
and gases are expanded. The expansion, and subsequent contraction
of atmospheric air, give rise to various winds, which are currents
of air rushing from one point of the compass to another to maintain
an equilibrium. The theory of the winds is predicated on this fact,
although some have asserted, that they depend greatly on the diurnal
motion of the earth. The air thermometer of Sanctorius, and the
differential thermometer of Leslie, are founded on this principle, of
the expansion of air. Fluids expand until they arrive at the boiling
point, as is the case with water, alcohol, &c. The expansion of
mercury, in a glass tube, furnished with a graduated scale, forms the
mercurial thermometer, by the rise and fall of which, the different
variations of temperature are marked.

Notwithstanding caloric has the property of expanding bodies, there
are some exceptions to this law, which may be proper to notice.
Water, for instance, at the temperature below 40° contracts at every
increment of temperature until it reaches 40°, which is its maximum
of density. Above 40° it expands, until it arrives at the boiling
point. Alumina, or pure argillaceous earth, also contracts by heat;
hence it is used in the pyrometer of Wedgwood, to measure by its
contraction intense degrees of heat. Various saline substances, in
the act of crystallization, also expand. Several of the metals, when
previously melted, on cooling exhibit the same character; and water,
in the act of freezing, exerts a powerful force by its expansion,
competent to the bursting of shells, and the splitting of rocks.

The changes in bodies, produced by caloric, we have already noticed.
We will only add, that fluids require different temperatures, called
the boiling point, to make them boil, under the same atmospheric
pressure. Water boils at 212°. Many observations have been made
with respect to water, both in the state of ice, and the state of
vapour. Besides the accession of 212 degrees of caloric, appreciable
by the thermometer, in water in the state of steam, there is also
an accession of non-distributable caloric, called _latent heat_,
which is calculated at 1000°. In consequence of this circumstance,
steam has been judiciously applied to various useful purposes, and
particularly in a certain manner for the drying of gunpowder.

That chemical changes are produced by the agency of caloric, is a
fact well known. It is supposed to occasion decompositions, according
to the laws of affinity, by changing previous affinities, and causing
new affinities to take place. Hence the operations by fire, whether
the substances themselves are exposed in a dry state to the action
of heat, or otherwise, produce new results, or compounds, which
could not be made without it. This truth has long been obvious.
In consequence of a knowledge of this fact, Dr. Black (_Lectures_
vol. i, p. 12,) defined "chemistry to be the study of the effects
of heat and mixture, with the view of discovering their general and
subordinate laws, and of improving the useful arts."

Caloric as a powerful auxiliary, performing as it does an innumerable
multitude of changes and effects, an agent by which the operations
of the universe are maintained in order and harmony for universal
good, exerts the same effect in the furnace of the chemist, as in
the great laboratory of nature; and regulates, and determines all
the consequences, which follow a succession of fixed, and appointed
changes.[4]

We have thus, in this brief and hasty outline of the nature,
principal effects, and properties of caloric, detailed the leading
facts on this subject; from which it will be seen, that caloric,
so far as respects its generation by the combustion of different
pyro-mixtures, and effects, generally, should form a part of
Pyrotechny, and claim the attention of those, who are connected with
the preparation of Fire-Works.

Respiration is also a process which puts quiescent heat in motion.[5]

In the second part of the work, we embrace the furniture of a
laboratory, for the use of fire-workers, consisting of various tools
and utensils.

Under this head, we also embrace sundry manipulations, such as the
preparation of substances for use, the manner of forming mixtures,
and various anterior operations. The formation of pasteboard for
cases, the mode of forming as well as charging cases, different
modes of charging rockets, the dimensions of rammers, mallets &c.
This preliminary ought to be well understood; as the successful
practice of the art depends greatly on these operations. We may
observe, however, that we have had occasion to repeat some of these
manipulations in certain instances, to make them more intelligible;
or rather to present, more in connection with the subject, a detail
of minutiæ.

In the different compositions, the reader will bear in mind, that
the copious collection of formulæ, both old and new, embraces all
the facts, with which we are acquainted, concerning pyrotechnical
preparations.

In most instances, where the importance of the subject required it,
we designated, or set apart from the rest, formulæ, which have been
_approved_, and particularly in France.

This is more particularly the case as it respects the fourth and
last part, which appertains exclusively to Military Fire-Works. On
this subject, permit me to remark, that fire-works, intended for the
purposes of war, should be depended on; and for that reason, in order
to produce a certain effect, the materials of which they are composed
should be pure, weighed with accuracy in the proportions required,
and carefully mixed according to the rules laid down. It is true,
however, that while this nicety is required in particular cases, it
is unnecessary in the formation of all fire-works. The composition
for carcass and light-ball, for tourteaux, links, and fascines, and
some others, do not require that precision; whereas the composition
for fuses for bombs, howitzes, and grenades should be in every
respect accurately made; for on the accuracy of the composition, must
depend the time a fuse will burn, which is afterwards regulated by
using more or less of the fuse, according to the time it will take
for the shell to reach its destination, on which depends the skill of
the bombardier. Accuracy, however, in making of preparations should
be a general rule.

Viewing Pyrotechny either as a science or an art, there is
undoubtedly required in its prosecution much skill and practice. A
knowledge of the theory of fire-works may be readily acquired. The
mere artificer or fire-worker, by constant habit and experience, may
understand it is true how to mix materials, prepare compositions,
charge cases, and perform all other mechanical operations; but it is
equally certain, that, without a knowledge of chemistry, he cannot
understand the theory. We would not say, that the workman should be
a chemist, but that he should know enough to determine the purity
of the substances he employs, and their respective qualities and
effects; for if that principle were admitted, we might go further
and say, that every person, who practices a chemical art, as the
tanner, gluemaker, brazier, &c. should be a chemist, or that the art
could not be conducted without a previous knowledge of chemistry,
which we know is contrary to fact. This, however, may be said, that
in _all_ arts which are decidedly chemical, as that of _dying_ for
instance, chemical knowledge will enable the artist or operator to
conduct his processes with better advantage, and correct any _old_
routine, which is too often pursued, because it was handed down
from generation to generation. Mr. Seguin in France facilitated the
preparation of tanned leather, by adopting a new process altogether
chemical. In a word, so far as chemistry is connected with the
arts, and by which we explain the operations that take place, it is
undoubtedly important; and with regard to Pyrotechny, it appears, in
the way we have mentioned, to be indispensable. Chaptal (_Elements de
Chimie_) observes, that the works of artificers frequently miscarry
in consequence of their being unacquainted with the art.

In noticing this subject, we may be permitted to digress, while we
state, that, being fully convinced of this truth, we have directed
our labours in the Chemical Department of the United States'
Military Academy to two distinct objects; _viz._ to theoretical
and experimental chemistry, forming the first year's course, and
chemistry in its application to the arts, manufactures, and domestic
economy, constituting, along with mineralogy, the course of the
second year. In addition to the usual applications, Pyrotechny, in
the manner we have stated, and especially that branch which treats of
military fire-works, has claimed our attention; and we have reason
to believe, that this addition, to the usual course of chemical
instruction, has considerably advanced the utility, especially to
gentlemen designed for the army, of the application of chemistry.

The system of instruction adopted throughout the academy, in the
different departments, (the plan of which may be seen in the new
_Army Regulations_, article Military Academy), which, we have no
hesitation in believing, is the most complete of any in the United
States, and by far the most extensive,[6] is so regulated, that each
section of a class regularly recite, and are interrogated on each
subject of instruction, so that, while an emulation to excel is thus
excited, the comparative merit or standing of the cadets is thereby
determined. Adopting the same system in the Chemical department,
that of interrogation on the subject of the preceding lecture, has
many peculiar advantages; so that, while the mind and memory of the
pupil are thus exercised, a comparative estimate of the progress of
each one is obtained during each week, by which we are enabled, as in
other departments, to present a Weekly Class Report of their progress.

While we are indebted to the talents and industry of the professors
and teachers of the Academy, for the flourishing condition it is now
in, and the progress of the cadets in every branch there taught; it
is but justice to remark, that for the present organization of the
academy, as relates to the studies, which is obviously preferable to
the old system, and also for the improvements in instruction, we are
indebted to the present superintendent, Col. S. Thayer, of the U. S.
corps of engineers.

Considering pyrotechny, abstract from the questions usually given,
and forming a distinct branch, it may be proper to remark, that the
interrogatories on this head have been minutely and satisfactorily
answered. The following outline will exhibit the order in which such
questions were put, observing, however, that they are merely in
connection with this subject:

What is saltpetre? What is nitric acid? What is potash? What are
the sources of saltpetre, and how is it obtained? How is it formed
in nitre beds, extracted, and refined? What circumstances are
necessary to produce nitre, and how does animal matter act in its
production? What is the difference between the old and new process
for refining saltpetre? What reagents are used to discover the
presence of foreign substances in nitre? What are nitre caves? Where
do they exist? What are the nitre caves of the Western country,
and how is nitre extracted from the earth? What proportion of
nitre does the saltpetre earth of the nitre caves afford? What is
the theory of the process for extracting saltpetre from nitrous
earth, or nitrate of lime? What is sulphur? How is it obtained,
and how is it purified for the manufacture of gunpowder? Of what
use is sulphur in the composition of gunpowder? Does it add to the
effective force of gunpowder? What is charcoal? What is the best
mode of carbonizing wood for the purpose of gunpowder? What woods
are preferred for this purpose? In the charring of wood, what part
is converted into coal, and what gas and acid are disengaged? What
is the use of charcoal in gunpowder? What is gunpowder? What are
considered the best proportions for forming it, and what constitutes
the difference between powder for war, for gunning, and for mining?
How does the combustion of gunpowder take place? Can you explain why
combustion takes place without the presence of a gaseous supporter of
combustion, as gunpowder will inflame in vacuo? What are the products
of the combustion of gunpowder? What gases are generated? To what
is the force of fired gunpowder owing? What are the experiments of
Mr. Robins on the force of gunpowder? How would you separate the
component parts of gunpowder, so as to determine their proportions?
What are gunpowder proofs? What is understood by the comparative
force of gunpowder? What are eprouvettes? &c. In noticing in the
same manner the preparations used for fire-works, and for war, as
the rocket for instance, the following questions were propounded;
_viz._ What is a rocket? How is it formed? Is the case always made of
paper? What is the war rocket? What is the composition for rockets,
and how does it act? What particular care is required in charging
a rocket? What is the cause of the ascension of rockets? What is
the use of the conical cavity, made in a rocket at the time it is
charged, or bored out after it is charged? How do cases charged with
composition impart motion to wheels, and other pieces of fire-work?
What is understood by the rocket principle? What is the rocket stick,
and its use? Is the centre of gravity fixed, or is it shifting in the
flight of rockets? How are rockets discharged? What is the head of a
rocket? What is usually put in the head? Are all rockets furnished
with a head? What is understood by the furniture of a rocket? How
are the serpents, stars, fire-rain, &c. forming the furniture of
a rocket, discharged into the air, when the rocket has terminated
its flight, or arrived at its maximum of ascension? What forms the
difference between a balloon, in fire-works, and a rocket? As the
balloon contains also furniture, and is projected vertically from a
mortar, how is fire communicated to it, so as to burst it in the air?
Is the fuse used, in this case the same as that for bombs, howitzes,
and grenades? What is the Asiatic rocket? The fougette of the French?
In what seige were they employed with success by the native troops of
India? What was the nature of their war-rocket? What is the murdering
rocket of the French? Is the conical head hollow, or solid, blunt or
pointed? Why is it called the murdering rocket? What is the Congreve
rocket? Is Congreve the inventor, or improver of this rocket? What
are Congreve rockets loaded or armed with? In what part is the load
placed? Is the case made of paper or sheet iron? What are the sizes
of Congreve rockets?

What are the ranges of Congreve rockets? What angle of elevation
produces the best range? How are Congreve rockets discharged in the
field, and what number of men are usually employed for that service?
Are the Congreve rockets considered to be a powerful offensive
weapon; and, if so, in what particular? What is a carcass rocket?
As an incendiary, is the carcass rocket equal to the usual carcass
thrown from mortars? What is the carcass composition made of? What is
the Congreve rocket light ball? In large rockets, are their sticks
solid, or bored and filled with gunpowder? Why is that expedient
used? &c.

It is obvious, that the student, after obtaining a knowledge of each
subject by the preceding lecture, accompanied with demonstrations, is
enabled to detail minutely all the facts in relation to it.

Pyrotechny, as known at present, is confined to a few books, and
scattered in a desultory manner, without any regular or connected
system. In fact the works which treat on this subject are in French,
or translations from the French on particular subjects, but generally
very imperfect. As applied to the uses of war, we may indeed say,
that the small treatise of Bigot, (_Traité d'Artifice de Guerre_),
and Ruggeri (_Pyrotechnie Militaire_) are the only works. We have,
therefore, consulted these authors, as will be seen in the pages of
the work.

Roger Bacon, in his _Opus Majus_, has given some account of the Greek
fire, and of a composition, which seems to have had the effect of our
modern gunpowder.

Malthus (_Traité de l'Artillerie_) contains some formulæ for Military
Fire-Works. Anzelet and Vanorchis, in their several works, have given
some receipts for incendiary preparations. Henzion (_Recreations
Mathématiques_) and Joachim Butelius have also something on the
subject.

The celebrated Polander, Casimir Siemienowicz, has nothing of any
moment, if we except the incendiary fire-rain, an account of which
may be seen in the fourth part of our work. His book is considered,
however, the best of the whole of them. Belidor, Theodore Duturbrie,
&c. have mentioned some preparations; but their works are chiefly
confined to artillery.

The improvement of Pyrotechny is ascribed to the Germans and
Italians, and the French acknowledge, that they are indebted for a
knowledge of it to the Italians. Be this as it may, it is certain,
that it was known in China from time immemorial. Their acquaintance
with gunpowder, before it was known in Europe, is a fact which
appears to be generally admitted. For an account of the Chinese
fire-works, and the origin of gunpowder in Europe, consult these
articles respectively.

Whatever merit we may claim in this work, as the public will be able
to judge impartially, it will be seen, by referring to the different
chapters and sections, that we have endeavoured to form a system, by
presenting a connected view of the whole subject.

Having noticed under separate heads, the particular use and
application of each composition, we have added a chapter on the
arrangement of fire-works for exhibition, together with the order
to be observed. We may remark here, that we have enlarged in this
part more perhaps than its merit or importance deserves; but, on
reflection, we thought it better to embrace the whole subject, in
order to form a more complete system in all its parts.

After going through the fire-works for exhibition, and noticing the
different formulæ, and preparations, for arrangement, with the
theory of effects, we consider, in the next place, a subject of
more importance, that of Military Pyrotechny. We have adopted this
arrangement, more on account of obtaining a better acquaintance with
ordinary fire-works, before the reader is prepared for military
works, which he will understand with more facility; for all the
preliminary operations precede the practical part.

On this head, it will be sufficient to add, to what we have already
stated, that we have given in each article, generally speaking, a
variety of formulæ, with ample instructions for the preparation of
each composition. The table of contents will exhibit the order in
which they are treated.

In noticing the substances used in fire-works, in the first part, it
will be perceived, that we have noticed some of them more extensively
according to their importance; as for instance, _saltpetre_. Besides
the different modes of obtaining saltpetre in Europe and elsewhere,
and the means employed for refining it, we mention the saltpetre
caves of the western country, which furnish an abundance of this
article, and which contain an almost inexhaustible supply.

The extraction of saltpetre from the earth, (principally nitrate of
lime), by using a lixivium of wood-ashes; the formation of rough,
and subsequently of refined nitre; the various methods of refining
saltpetre, and particularly that adopted in France; with sundry facts
respecting the origin of nitre, and on the formation of artificial
nitre beds; all claim our particular notice.

The extraction of sulphur from its combinations, and the means used
for purifying it for the purpose of gunpowder, are also considered in
the same manner.

The subject of charcoal, an essential constituent of gunpowder,
claims, in like manner, particular attention. The various modes
of charring, the woods employed, the quantity of coal obtained,
the formation of pyroacetic acid in the process of carbonization,
and many facts of the same kind are considered. These subjects,
_viz._ nitre, charcoal, and sulphur, are highly important to the
manufacturer of gunpowder.

A knowledge of the various processes for refining saltpetre; the best
and most approved modes of carbonizing wood; the purification and
quality of sulphur; the different processes for making gunpowder,
with the proportion of the ingredients used in France and elsewhere;
the granulation, glazing, and drying of powder, the use of the steam
apparatus, and the different modes of proving it, and of examining
it chemically; and the means of ascertaining the purity of nitre in
any specimen of gunpowder; are, with others, subjects of particular
interest to the gunpowder manufacturer.

With respect to the Theory of the explosion of gunpowder, we have
noticed it at some length, and have added the experiments and
observations of Mr. Robins, and of other persons, made at different
periods.

In the consideration of the gaseous products, and the caloric evolved
by the combustion of powder, we have taken a view of the gases
produced, the cause of their production, the dilatation which they
suffer, and the experiments of Lavoisier and Laplace, with regard to
latent heat, and deducing therefrom some views of the probable cause
of the production of caloric in fired gunpowder.[7]

Our observations respecting rockets, the theory of their ascension,
of the Congreve carcass and Asiatic rockets, and some others, are
we apprehend sufficiently extensive. As it regards the different
incendiary compositions, and their use in war, the reader will find
ample instructions on these heads.

We may also remark, that we have given some of the more common, or
general properties of the substances, employed in the composition of
fire-works, without going into that detail, which belongs exclusively
to works that treat of Chemistry. It was neither our design, nor have
we given, for the reasons thus stated, _all_ the chemical characters
or properties of the substances so employed; and, therefore, have
confined ourselves, generally speaking, to an enumeration of such
properties as are connected with the subject, or are indispensably
necessary to be known, before a rationale of the causes and effects
can be understood.

It was our intention to accompany the work with plates, exhibiting
the arrangement, &c. of fire-works, which, there can be no doubt,
would have facilitated in particular the knowledge of forming, and
arranging, certain pieces of fire-work; but, on second reflection, as
such illustrations were connected more with fancy exhibitions, and
have little or no relation to Military Fire-works, the most useful
branch of Pyrotechny, we were finally of opinion, that the addition
of plates would greatly enhance the price, without advancing or
adding to the value of the work.

If, however, a second edition should be required, various figures
in illustration of particular subjects may be added, either with
a distinct explanatory chapter, or a reference from the articles
themselves, with the necessary explanation, to the figures
respectively.

It would require at least twenty-five plates to include all the
figures we originally intended to have introduced.

Before concluding this introduction, it remains for us to remark,
that, in forming this work, we consulted a variety of authors, but
with little advantage, except some French works, which we shall
notice. Chaptal (_Chimie Appliqué aux Arts_;) Bigot (_Artifice de
Guerre_;) Morel (_Feux d'Artifice_;) Thenard (_Traité de Chimie_;)
Ruggeri (_Pyrotechnie Militaire_;) MM. Bottée and Riffault (_Traité
de L'Art de Fabriqué la Poudre à canon_;) Peyre (_Le Mouvement
Igné_;) Biot (_Traité de Physique_, _Recherches Experimentales et
Mathématique_, _sur les mouvement des Molecules de la Lumiere_,
_&c._;) M. Duloc (_Theorie Nouvelle sur le Mechanisme de
l'Artillerie_;) the _Dictionnaire de l'Industrie_; the _Dictionnaire
Encyclopedique des Arts et Metiers Mecaniques_, article _Art de
L'Artificier_; _Œuvre Militaire_; _Archives des Découvertes_;
_Système des Connoissances Chimiques par A. F. Fourcroy_;
_Aide-Mémoire a l'usage des officiers d'Artillerie de France_.

We examined various authors in English; and with regard to the origin
of inventions, we found the learned, and valuable work of professor
Beckman (_History of Inventions_) very useful, and likewise James's
_Military Dictionary_. To the _Encyclopedia Britannica_, we are
indebted for many interesting facts, and some extracts on fire-works
for exhibition.

On the subject of mining, we consulted the _Treatise on mines for the
use of the Royal Military Academy_, by Landmann.

We deem it necessary to observe, that, in collecting our formulæ for
military fire-works, although we have sometimes extracted from the
Strasbourg _Memoir_, the _Bombardier and Pocket Gunner_, and the
_Military Dictionary_ of Duane and James, we have generally followed
Bigot; as the formulæ which he gives for the preparation of Military
fire-works have been approved by the French government; and where
any thing of importance occurred in Ruggeri, we have, for the same
reason, extracted such formulæ from that author.

As respects the turtle, torpedo, and catamarin, submarine machines,
it appears that Bushnel (_Trans. Am. Phil. Soc._) claims the
originality of the discovery from the date of his invention,
although similar contrivances had long ago been suggested. Fulton's
improvements, in the torpedo, are deserving of particular attention;
but it is plain, that the Catamarin of the English is the same in
principle and application as Fulton's torpedo, and that Fulton
deserves the merit of it. Congreve, if we believe Ruggeri, was not
the inventor of the rocket, which bears his name; for, according
to him, it was invented about the year 1798 by a naval officer at
Bourdeaux. It is certain, however, it was neither much known, nor
used before the attack on Copenhagen.

It is certain that the present incendiary fire-stone was taken
from the recipe for fire-rain contained in the military work
of Cassimir Siemienowicz, or that the fire-rain gave rise to a
similar preparation. The idea of the _pyrophore_, mentioned in the
_Archives des Découvertes_, must have originated from the use of the
powder-barrel, and of similar means of defence. We might enumerate
many other inventions, which owe their origin in the same way.

A SYSTEM

PYROTECHNY.

CHAPTER I.

PYROTECHNY IN GENERAL.

_Sec. I. Definition of Pyrotechny._

Pyrotechny is defined the doctrine of artificial fire-works, whether
for war or exhibition, and is derived from the Greek, πυρ _fire_, and
τεχνη _art_. In a more general sense, it comprehends the structure
and use of fire-arms, and the science which teaches the management
and application of fire in several operations.

_Sec. II. General theory of Pyrotechny._

In the composition of artificial fire, various substances are
employed, having different properties, and designed to produce
certain effects characterised by particular phenomena. These
substances are either inflammable, or support the combustion of
inflammable bodies. As pyrotechnical mixtures are differently formed,
and of various substances, the effects are also modified, although
combustion, under some shape always takes place.

Combustion is either modified, retarded, or accelerated; and
in consequence of the presence of certain substances, different
appearances are given to flame.

The conditions necessary for combustion are, the presence of a
combustible substance, of a supporter of combustion, and a certain
temperature. Thus, charcoal when raised to the temperature of 800° in
the open air, takes fire. This elevation of temperature enables it
to act chemically on the oxygen gas of the atmosphere; the latter,
as it comes in contact, being decomposed. Now, as oxygen gas is a
combination of oxygen and caloric, the caloric being in a latent
state, the charcoal unites with the oxygen, and the phenomena of
combustion ensue; that is, an evolution of _heat_ and _light_.
The caloric of the decomposed gas is given out in a free state,
and, according to the theory of Dr. Thomson, (_Thomson's System of
Chemistry_, vol. i.) the light proceeds from the burning body. We
have then an instance of combustion, in which there is a combustible,
a supporter of combustion, and an elevated temperature. The old
theory of combustion, called the _Stahlian_ theory, which presupposes
an element called phlogiston, or a principle of fire, to exist in all
bodies under some modification, would explain these effects by merely
supposing, that combustion was nothing more than a disengagement of
phlogiston; and that when a body had lost its inflammable principle,
(as a metal, when oxidized), it became dephlogisticated. But,
as it proved that phlogiston is a hypothetical element, and the
anti-phlogistic doctrine clearly shows, that combustion is no other
than a process which unites the supporter with the combustible,
forming new products; it follows, that, in all changes of the kind,
the same reasoning will apply, and the same principle be tenable.

The products of combustion depend on the nature of the substance
burnt, and the supporter employed. Thus, in the instance just
mentioned, the charcoal, by its union with oxygen, is changed into
carbonic acid, which takes the gaseous state. We say then, that
carbonic acid is the product of the combustion of charcoal, or,
chemically speaking, of carbon. As resins, oil, &c. contain hydrogen,
as well as carbon, the products in such cases would be water, as well
as carbonic acid.

The chemical effects, therefore, which we consider in fire-works,
forming the basis on which a theory of sundry phenomena may be
formed, are no other than the result of the action of one body
on another, according to the laws which govern such action, and
the consequent operation of chemical combination. Combustion, in
fire-works, may be considered a primary agent in _all effects_ which
characterise artificial fire.

The second change, with respect to the appearance of the flame,
the formation of stars, serpents, rain, &c. terms used in the
art, is owing either to new chemical changes which the substances
undergo, or to the decomposition of the products themselves. These
effects, it is obvious, must be governed by the circumstances,
under which the mixtures are made. Saltpetre, for instance, is the
basis of fire-works, whether used in a separate state, or employed
in mixture with charcoal and sulphur, as in gun-powder; and, from
its composition, is adapted to all the purposes of the art, because
it yields its oxygen very readily to all inflammable bodies. In
consequence of the decomposition, it undergoes at an elevated
temperature, when brought in contact with charcoal, sulphur, &c. and
various substances which contain carbon, as pitch, rosin, turpentine,
tallow, copal, and amber, combustion results, and, according to
circumstances, is more or less rapid, and the flame also more or less
brilliant.

When charcoal, in the state of ignition, is brought in contact with
nitre, a deflagration takes place, because, at the temperature of
ignition, it has the property of decomposing the nitric acid of the
nitre; and as this process unites the carbon with the oxygen, in
the proportion necessary to constitute carbonic acid, this acid is
accordingly produced. When, therefore, we inflame a mixture of nitre,
charcoal, and sulphur, or gun-powder, the whole or greater part
disappears; and if we were to collect in a pneumatic apparatus, the
products of the combustion, it would be found, that they are nearly
altogether gaseous, and composed, as we shall speak hereafter, of
sundry elastic aëriform fluids. This decomposition, the immediate
effect of the charcoal on the nitric acid of the nitre, is the same
as in the preceding instance, for carbonic acid gas is formed in both
cases. We have then another instance of combustion, where a number
of substances are concerned, and therefore, the products must be
numerous.

We notice this subject more particularly, since, as in the different
fire-works, nitre and inflammable bodies are used in different
proportions, the result is always affected by the same laws of
chemical decomposition; for the same substances, placed under similar
circumstances of proportion, mixture, &c. afford the like results.
If carbon alone be employed, carbonic acid gas is the result; if
oil, tallow, rosin, or turpentine be used, we have then, as we had
occasion to remark, water, as well as carbonic acid, by reason of
the union of the hydrogen, which forms one of their constituent
parts, with a part of the oxygen of the nitric acid.

Again, in a composition of mealed powder, rosin and sulphur, with
or without the addition of saw dust, we infer, from the composition
of the ingredients and the chemical action which subsequently takes
place, that the products of combustion would be carbonic acid gas,
sulphurous acid gas, water, sulphuretted hydrogen, and probably
azotic, and nitric oxide gases. If the filings of steel, brass,
zinc, or copper, enter into the composition, besides the products
above-mentioned, there would be either an oxide of iron, an oxide
of zinc, or, an oxide of copper, according as one or other of these
metals are employed.

Copper, in fire-works, has the effect of communicating a green
colour to the flame. M. Homberg, (_Collection Acad._) observes, that
the green colour in such cases is owing to the _dissolution_ of
the metal, which in fact is nothing more than the _effect_ of its
oxidizement.

The various compositions for brilliant fire, as the Chinese fire, owe
their peculiar character to pulverised cast iron, and commonly to
steel and iron filings. Now the effects in these cases are the same;
for the same oxidizement ensues, more or less rapidly, which in fact
distinguishes the kinds of brilliant fire. That of the Chinese is the
most perfect, and next is the composition made with steel filings. It
will be seen, however, that compositions generally are governed, in
their respective appearances when inflamed, by the purity, as well as
the proportion of other substances, which enter into them; and hence
much of their effect depends on collateral circumstances, which we
purpose to consider when we treat of the compositions individually.

That the light of certain burning bodies may be increased, is evident
from these facts; and experiment has shown, that the intensity of
the light of burning sulphur, hydrogen, carbonic oxide, &c. is
increased by throwing into them, zinc, or its oxide, iron, and other
metals, or by placing in them very fine amianthus or metallic gauze.
Protochloride of copper burns with a dense red light, tinged with
green and blue towards the edges. If the hydrogen of the oil acts in
separating the chlorine from the copper, and the reduced copper is
ignited by the charcoal, this appearance must necessarily ensue.

When solid matter is the product of combustion, as in the burning
of phosphorus, zinc, iron, &c. the flame is remarked to be more
intense. Flame may be modified under other circumstances, as we will
have occasion to mention hereafter. When, for instance, a wire-gauze
safety-lamp is made to burn in a very explosive mixture of coal gas
and air, the light is very feeble and of a pale colour; but when a
current of coal gas is burnt in atmospheric air, the combustion is
rapid and the flame brilliant.

Dr. Ure thinks it probable, (_Dictionary of Chemistry_, article
combustion,) that, when the colour of the flame is changed by the
introduction of incombustible compounds, the effect depends on the
production, and subsequent ignition or combustion of inflammable
matter from them. Thus he infers, that the rose-coloured light given
to flame by the compounds of strontium and calcium, and the yellow
colour given by those of barium, and the green by those of boron, may
depend upon a temporary production of these bases, by the inflammable
matter of the flame. It is inferred also, as a probable conclusion,
that the heat of flames may be actually diminished by increasing
their light, (at least the heat communicable to other matter), and
_vice versa_; because, in the most intense heat, as in the compound
blow pipe, or in Newman's blow pipe apparatus, in which a mixture of
oxygen and hydrogen gases is compressed, the flame, although hardly
visible in bright day light, instantly fuses the most refractory
bodies; but the light of solid bodies ignited in it, is so vivid as
to be painful to the eye.

Some curious facts with regard to flame, in connection with
electricity, are given by Brande in the Phil. Trans. for 1814. He
supposes that some chemical bodies are naturally in the resinous,
and others in the positive electrical state. He supposes also,
as a consequence, that the positive flame will be attracted, and
neutralize the negative polarity, while the negative flame will
operate a similar change by inducing an equilibrium at the positive
pole. Thus he found, that certain flames were attracted by the
positive ball of an electrical apparatus, and others attracted by the
negative ball. The flame of sulphur and phosphorus is attracted by
the positive pole, and the flame of camphor, resins, and hydrogen by
the negative pole.

In relation to the production of flame, we may observe, that, as
sundry solid and fluid substances are inflammable, the products of
combustion depend on the composition of the substance made use of,
and the condition under which it is burnt. As to gaseous substances
that are inflammable, the base of some gases, we may remark, as
carbon and hydrogen, unite in the process of combustion with the
base of other gases, (as oxygen;) and in other instances, the _gas_
itself takes fire, and exhibits the phenomena of flame. Now carbonic
acid gas extinguishes flame, although its base is inflammable; but
hydrogen, as well as hydrogen gas, is inflammable, and when burnt in
oxygen gas or atmospheric air produces water, which also extinguishes
the flame of burning bodies.

As we will have occasion to notice a variety of aëriform fluids,
especially when we treat of the aëriform products of fired
gun-powder, a few remarks on this head may be useful at this time.

By the combustion of bodies, substances are generated that are
either gaseous or solid, whence arises the variety of products. Of
aëriform fluids, some are coloured, as nitrous acid vapour, (nitrous
gas and oxygen), chlorine, and the protoxide and deutoxide of
chlorine. The first is red, the rest yellowish-green, or yellowish.
Some relight a taper, provided the wick remain ignited, as oxygen
gas, protoxide of azote, and the oxides of chlorine. Others produce
_white vapours_ in the air, as muriatic acid, fluoboric, fluosilicic,
and hydriodic. The inflammable gases, which take fire in the air
by contact of the lighted taper, are hydrogen, hydroguret, and
bihydroguret of carbon, carbonic oxide, prussine or cyanogen,
called also carburet of azote, and phosphuretted, sulphuretted,
arsenuretted, telluretted, and potassuretted hydrogen. Other gases
are acid, and redden litmus, which, for that reason, are called acid
gases, such as nitrous, sulphurous, muriatic, fluoboric, hydriodic,
fluosilicic, chlorocarbonic, and carbonic acids; the oxides of
chlorine, sulphuretted hydrogen, telluretted hydrogen, and carburet
of azote. Some gases are destitute of smell, as oxygen, azote
and its protoxide, and carbonic acid; while others have a strong
and characteristic odour, as ammoniacal gas. Some gases are very
soluble in water, and others but slightly soluble, such as fluoric,
fluosilicic, carbonic, sulphurous, and muriatic acids, and ammoniacal
gas. Alkaline solutions absorb some gases, as nitrous, sulphurous,
muriatic, fluoboric, carbonic, hydriodic, fluosilicic, chlorine,
chlorocarbonic, and the two oxides of chlorine, sulphuretted
hydrogen, telluretted hydrogen, and ammonia. Alkaline gases are
ammonia, and potassuretted hydrogen.

The character of gases is well defined. The compound gas of
phosphorus and hydrogen takes fire spontaneously in the atmosphere,
burning with a brilliant white flame; but there is another gas formed
of the same substances, that does not inflame spontaneously, but is
inflammable, called subphosphuretted hydrogen. This gas has a strong
smell of garlic or phosphorus, and is luminous in the dark. It may
be this peculiar combination, which gives rise to the _ignes fatui_;
but the permanent ignes fatui, observed in volcanic countries, are
said to be the slow combustion of sulphur, forming sulphurous acid
gas. Sir H. Davy found, that phosphuretted hydrogen produced a flash
of light when admitted into the best vacuum that could be made by an
excellent pump of Nairn's construction.

Naphtha in contact with red hot iron glows with a lambent flame
at a rarefaction of thirty times, though its flame ceases at an
atmospheric rarefaction of six. Camphor ceases to burn in an air
rarefied six times, but, in a glass tube which becomes ignited,
the flame of camphor exists under ninefold rarefaction; whereas
phosphorus, according to the experiments of Van Marum, will burn,
although the atmosphere be rarefied sixty times. Hydrogen gas will
burn in a rarefied air, when it is four or five times less than the
pressure of the atmosphere, and its flame be extinguished, when the
pressure is between seven and eight times less; from which it is
inferred, that the flame is extinguished in rarefied atmospheres,
only when the heat it produces is insufficient to keep up the
combustion. Olefiant gas (hydroguret of carbon) ceased to burn in an
atmosphere, where its pressure was diminished between ten and eleven
times. The flames of alcohol and of wax taper were extinguished in
an atmosphere, where pressure was five or six times less without
the wire of platinum, and seven or eight times less when the wire
was kept in the flame. See _Flameless Lamp_. Several interesting
conclusions may be drawn from these facts, which, to enumerate, would
lead us beyond our design. It will be sufficient, therefore, to
add, that although a supporter of combustion is necessary for that
process, and flame may be differently modified, yet combustion ceases
if the pressure of the atmosphere be diminished in certain ratios, as
already noticed.

Besides nitre, other saline substances which contain oxygen feebly
combined, have been used for the same purpose. Some years ago, it
was proposed to substitute the hyper-oxymuriate, now called chlorate
of potassa, for nitre in the formation of gun-powder. As chlorate
of potassa, when mixed with sulphur, &c. produces combustion by
percussion, or by the contact of fire, this effect is attributed to
the same cause,--the separation of oxygen, not from azote, but from
the chlorine of the chloric acid, Hence, when that salt is used in
fire-works, the result of the combustion is similar to that in which
nitre is employed; at least as regards the union of the oxygen with
the elementary principles of the inflammable body. On this subject,
we shall make some remarks hereafter. Nitrate of soda, a salt which
contains nitric acid, and similar to saltpetre in that particular,
has been recommended also for fire-works. It has, however, several
objections. Our object in noticing it at this time is to remark,
that, when it is so employed, its effect is the same as nitrate of
potassa, or saltpetre, by furnishing oxygen as the supporter of
combustion. See _Nitrate of Soda_.

We are of opinion, that many of the nitrates might be advantageously
employed in the manufacture of fire-works. Some, as nitrate of
strontian, communicate a red colour to flame, as the flame of
alcohol. Nitrate of lime also might be used.

All nitrates, as well as the different hyperoxymuriates, or
chlorates, contain oxygen as an essential ingredient in the acid of
their respective salts, which is readily given up to inflammable
substances.

When nitrates are employed for fire-works, they should be free from
moisture, or water of crystallization, unless otherwise required.
The presence of water may, in many cases, prove injurious to the
composition; and, consequently, the effect in those instances, may be
influenced by this circumstance. The composition of nitric acid, and
the action of carbon in the decomposition of the nitrates, or salts
formed by the union of nitric acid with sundry bases, will claim our
attention in the article on gun-powder.

With respect to the production of colours, some remarks on this
subject may be here added.

Speaking of colours, Haüy (_Elementary Treatise of Natural
Philosophy_, trans. ii. p. 253.) takes into view their formation
according to the Newtonian doctrine; and in a note by the translator,
several instances are given of the change of colour by oxidizement
and other processes. Iron when exposed to heat in contact with
atmospheric air gradually absorbs oxygen, and changes its colour.
The colours produced depend entirely on the quantity of oxygen, and
on the absorption of some of the rays of light, and the reflection
of others. See _Iron_. The tempering of steel instruments depends on
this property, and also the blueing of sword blades, and many similar
operations. The first impression of fire usually developes a blue
colour; a second degree produces a yellow; and, if the oxidizement
augments, the iron becomes red. The major part of the metals present
similar phenomena.

In vegetables, the blue colour is formed by fermentation; and many of
these colours are susceptible of passing to red by a greater quantity
of oxygen, as they depend on the absorption of oxygen. It is thus
that the green fecula of indigo becomes blue; turnsol, red by air and
acids; and the protoferrocyanate of iron, blue when exposed to the
air.

When meat putrefies, the first degree of oxygenation decides the blue
colour; the red soon succeeds as the process goes on. It would seem
that the maximum of oxidation determines the reflection of rays of
every kind, in the same proportions as subsist in solar light, of
which we have many instances in combustion.

The flame of burning bodies exhibits the same phenomena. It is blue
when the combination of oxygen is slow; red when it is stronger, and
white when the oxygenation is complete.

These facts lead to the conclusion, that the combination of oxygen,
and its proportions, give birth in bodies to the property of
reflecting corresponding rays of light; but, since the combination
of oxygen in different proportions ought to change the thickness
and density of the component laminæ, and, consequently, to produce
variations in the colours, this doctrine is not easily reconciled
with the received theory.

By considering the temperature necessary to inflame different bodies;
the nature of flame, and the relation between light and heat, which
compose it; the caloric disengaged in a free state during the
combustion of bodies, and the causes, which modify the appearance
of flame,--we may be enabled to account for the phenomena already
noticed. Thus, phosphorus at 150°, and sulphur at 550°, are said
to take fire, and two acid products are formed; at 800°, hydrogen
gas explodes with oxygen, and produces water; and, according to
Ure's view, the flame of combustible bodies may in all cases be
considered as the combustion of an _explosive mixture_ of inflammable
gas, or vapour, with air; and as to the change of quiescent into
distributable heat, and the causes that modify combustion and flame,
the facts on these heads are numerous and very important.

_Sec. III. Remarks on the Nature of particular Compositions._

The _spur fire_, which was invented by the Chinese, but brought to
perfection in Europe, is remarkably beautiful when employed in some
particular parts of fire-works. This fire was so named from the
effect it produces, that of forming scintillations, resembling a
shower, or drops of rain, or the rowel of a spur. The _artificial
flower pot_ is formed of this fire. The _stars_ and _pinks_, which
it produces, are said to be brilliant. The composition of spur
fire being saltpetre, lampblack, and sulphur, in the proportions
we shall give hereafter, is similar in fact to that of gunpowder;
for the lampblack acts in the same manner as common charcoal. As
the lampblack, however, is extremely fine, and of a purer quality,
its action on that account may be more powerful. While one portion
of it decomposes the nitric acid of the nitre, with the oxygen of
which it forms carbonic acid; another portion is thrown off in
actual combustion, which puts on the appearance we have mentioned.
Lampblack, it is to be observed, is a very impalpable powder, and
takes fire with more facility than pulverised charcoal.

The lampblack, therefore, is consumed both by the oxygen of the
nitre, and the oxygen gas furnished by the atmospheric air. With
respect to the sulphur, it facilitates the combustion, as it is
more readily inflamed, and it forms in the process of combustion,
sulphurous acid gas. Spur fire has been improved by the addition of
steel filings: They produce very brilliant scintillations, in the
combustion of which, oxide of iron is formed.

With respect to the composition of rockets, the materials of which
are united in different proportions, we will remark at this time,
that as mealed powder, saltpetre, and charcoal constitute their
principal ingredients, the chemical effect is similar to that we
have stated. The combustion of such mixtures is attributed to the
same cause; for whether we consider the composition of gunpowder, or
the extra addition of saltpetre and charcoal, or the substitution
of nitre for the gunpowder, the action must be the same, and
therefore the products of combustion, similar. The action, however,
as the effect evidently shows, is affected by the proportion of
the substances employed, and by other circumstances which we shall
notice hereafter. The different appearances, therefore, are owing
entirely to the composition, as in _rocket stars_, _rains_, _gerbes_,
_tourbillons_, _&c._

It may appear surprising, that the combustion of gunpowder with
other substances, previously well rammed in cases, as in the rocket,
will give to the case a _momentum_ of great velocity and force.
This motion is regulated by the _balance_ of the rocket; and its
_power_ depends upon the size of the case, and the compactness of
the composition. There is nothing new, however, in the fact; for it
is perfectly familiar with every one, if we consider the recoil of
a gun when fired, the powder having a resistance to overcome, as the
ball, that the explosive effect of gunpowder is equal, and that the
gases produced impel on all sides. Now the effect of a ball is as
the difference of its weight with the weight of the gun; while the
one being so much lighter is propelled forward with great celerity,
and with a corresponding projectile force, the other suffers but
little motion, which we term the recoil. The combustion of the
materials, of which a rocket is composed, in a case, and in many
fire-works where the cases are arranged on wheels, &c. which act on
the rocket-principle, produces in like manner a force proportionate
to the quantity of the material employed, and the manner it is driven
in the case. The force in such instances is given to the rocket by
the combustible substances; and the rocket itself when free, will
ascend, or move in the direction required; or if small cases are
fixed on wheels, which move on an axis, they communicate motion, as
in the single vertical wheels, horizontal wheels, plural wheels, and
the like, and may then be considered a moving power. That rockets
are used as a missile weapon is well known. They were employed by
the native troops of India against the British during the siege of
Seringapatam in 1799. Mr. Congreve, the inventor of the _war-rocket_
which bears his name, may have received his first idea of using
rockets from this circumstance. This rocket will be described
hereafter. The projectile force of the rocket is well calculated
for the conveyance of case shot to great distances; because, as it
proceeds, its velocity is accelerated instead of being retarded, as
happens with every other projectile, while the average velocity of
the shell is greater than that of the rocket only in the ratio of 9
to 8. The basis of this increase of power in the flight of rockets,
induced Congreve to make a number of experiments, which resulted in
their improvement, so far as they may be used of various calibres,
either for explosion or conflagration, and armed both with shells and
case shot. It may be sufficient to remark, that the 32 pr. rocket
carcass, which has been used in bombardment, will range 3000 yards
with the same quantity of combustible matter as that contained in the
ten inch spherical carcass.

M. de Buffon, (_Mémoires de l'Académie_, 1740,) wrote an ingenious
essay on sky rockets, in which he states the appendages which may be
put to them.

If we inquire into the cause of the ascension of rockets, it will
appear, that this apparently extraordinary effect, as we have
already remarked, is owing to the decomposition, and the consequent
production and disengagement of a large quantity of gaseous fluid
and caloric. The impelling power, as in the large Congreve rocket,
of which we had occasion to speak, is regulated in proportion to its
size, and the accuracy with which the materials have been driven.

The manner in which the flame, and, consequently, the gases are
expelled from the orifice of a rocket, resembles the operation of an
æolipile, which throws out the vapour of water, and sets in motion
the air in its vicinity. As the more flexible must yield to the more
solid body, so, in this respect, the gases produced are repelled by
the air in contact with the orifice of the rocket. Thus it follows,
that the rocket _displaces_ a volume of air of a much greater weight
than itself. The rocket then has upon the air, reasoning _a priori_,
the same effect as the oars of a boat have upon water; and hence,
the greater the volume of fire from the rocket, the greater is
its velocity and ascent. The impelling force also increases as it
consumes, being a uniformly accelerated motion.

It also appears, that a rocket sent in an horizontal direction will
not pass over so great a distance, as when its motion is vertical;
for, a rocket, directed in a line parallel to the horizon, passes
through a medium of equal density, but if directed perpendicular to
the horizon, from the moment it leaves the ground till it arrives at
its greatest height, it penetrates and passes through an atmosphere
whose density is continually decreasing, and consequently its
impelling force meets with less resistance. But when we consider the
increase of the force of the rocket, there is no comparison between
that force, and the diminution of the density of the air.

From these premises it follows, that the ascension of rockets of
all kinds is governed by one principle, namely, the disengagement
of gaseous fluids and caloric, which displacing an equal volume of
atmospheric air, operates by mutual contact.

Since, however, the air is heavier than the gases produced by the
rocket, as the latter are greatly expanded, it is evident, that the
gases will ascend; their specific gravity at the time of dilatation
being less than that of the air.

The gases proceeding from the interior of the rocket, act therefore
upon the air in the immediate vicinity of the orifice, and the rocket
is consequently propelled, the stick guiding it in the direction
given to it. If it were not for the rocket-stick or balance, its
direction would be neither regular nor certain. Considering then,
that, by the rocket-stick, the centre of gravity is changed from
the rocket itself to the stick, the motion is regulated in its
perpendicular flight by the stick. The rocket-stick must be always of
a proportionate length and weight to the rocket.

The motion given to rockets is always to be considered, for this
depends upon the direction at first imparted; but the force of
ascension is regulated by the size, and other circumstances which we
have mentioned.

Assuming the principle of constant force acting upon the rocket, its
velocity will increase with the time, and will be as the squares of
the time, according to the principles of uniform accelerated motion;
but if the force varies from uniformity, then the velocity and spaces
will proportionably vary.

As action and re-action must be equal, the repulsion produced by the
action of the gases upon the air is equal to the force impelling the
rocket. The constant action produces equal acceleration of the motion.

On the subject of the condensation and dilatation of air, and the
different pressures at a mean temperature, which is more or less
connected with this inquiry, the reader may consult with advantage,
the work of Mr. Biot, (_Traité de Physique_, &c. tome i, p. 110,
and 141.) The conclusions of Mr. Robins on the gaseous products of
gunpowder, and the elasticity of those products, may be seen by
referring to the article on _gunpowder_.

It must be confessed, that the theory of rockets differs in many
essential particulars from that of the usual projectiles; for
the motion of rockets is more complicated than that of common
projectiles, and is described to partake of all the anomalies that
attend the accelerated motion arising from the rocket composition,
and the uniform motion of the rocket-case, after the composition is
expended. It is a fact, which appears to be established, that little
or no advantage has yet been gained from the experiments that have
been made with cannon, even where the angle of elevation, and the
initial velocity of the ball were both accurately known. It seems
totally useless to look for mathematical investigations, with respect
to determining the ranges, &c. of military rockets; because, if we
could determine, with the greatest accuracy, the point, position,
and velocity of the rocket, at the moment when the composition was
expended, the remaining part of its track would still be subject
to all the inequalities attending on common projectiles. During
the burning of the rocket, however, its motion might, by a series
of experiments, be reduced to precise rules. As the principles of
gunnery, or rather of projectiles, involve a number of collateral
circumstances, such as the exact momentum of any given ball when
projected with a given velocity, and from a given distance, the
subject is still not fully settled; but they are so far conclusive,
that the resistance of the air to the same ball is as some function
of the velocity. The remarks of Dr. Hutton on this head would be too
lengthy. A rocket, however, is very different. The very medium, in
this case, is the principal agent in producing the motion; and being
enabled to ascertain all the successive energies of the propelling
power, and the resisting force, we may thus far determine correctly.
It is suggested, that a rocket fixed to the ballistic pendulum would
determine its whole energy; but, in order to make the experiment more
perfect, it is proposed to attach it to a wheel, or revolving body,
and then to measure its successive energies by the motion of some
weight attached to the revolving axis of the machine. It is worthy of
remark, that it is impossible to accommodate or determine the motion
of rockets by other projectiles; and, therefore, to ascertain their
momentum, such a contrivance would be eminently useful.

Mr. Moore of the Royal Military Academy, Great Britain, (_Treatise
on the motion and flight of rockets_,) who seems to have adopted the
hypothesis of Dr. Desaguliers, respecting the momentum of the ignited
composition, has given a variety of problems relative to the motion
and flight of rockets in non-resisting mediums, some of which we
purpose to notice.

Mariotte and Desaguliers have given two distinct theories of the
motion of rockets. The latter ascribes their motion to the momentum
of combustion, and the former to the elastic nature of the gaseous
fluid, generated by the combustion, and the resistance of air. The
observations of Desaguliers are the following: "Conceive the rocket
to have no vent at the choke, and to be set on fire, the consequence
will be, either that the rocket will burst in the weakest place,
or if all the parts be equally strong, and be able to sustain the
impulse of the flame, the rocket would burn out immoveable. Now, as
the force of the flame is equable, suppose its action downwards, or
that upwards, to lift 40 pounds; as these forces are equal, but their
directions contrary, they will destroy each other's action. Imagine
then the rocket opened at the choke; by this means, the action of the
flame downwards is taken away, and there remains a force equal to
forty pounds, acting upwards, to carry up the rocket and stick." This
theory, however ingenious, is not altogether true; for it is asserted
on the contrary, that the action of the flame or gas within the
rocket, when closed, as supposed above, is conceived to arise wholly
from the elastic nature of the gas, and the reaction it experiences
against the ends and sides of the rocket-case; the whole of which
ceases as soon as a free vent is given to the flame; and, therefore,
if a rocket could be fixed in a vacuum, as the flame would, in that
case, experience no resistance, there would be no reaction, and
consequently, no motion would ensue. Some experiments, analogous to
this position, have been made. We may merely add, with respect to
Mariotte's theory, that he attributes the motion of the rocket to
the resistance and reaction of the air, in consequence of which the
propelling force will decrease as the velocity increases, owing to
the partial vacuum left behind the rocket in its flight; so that the
correct solution of the problem necessarily involves the integration
of partial differences of the highest orders.

We may remark also, from the premises already established, that the
first motion of the rocket, like all other motions not produced by a
great momentary impulse, is slow; and before the stick is clear of
the flame, gravity has been acting upon the rocket, and depressed it
below its natural position, while the stick is prevented from being
equally depressed, by the top of the frame; so that the angle of
projection is in fact considerably less than the angle of the frame,
or slope of the rocket's first position. In consequence of this, the
rocket has the appearance of falling the moment after projection;
and, for this reason also, the angle for producing the greatest
range of a rocket exceeds very considerably that which gives the
extreme range of a shell projected from a mortar. There are various
propositions given by Mr. Moore respecting rockets, but to give the
calculus, &c. would take up more room than we could appropriate to
this abstract question. The nature of these propositions, however,
may be given in a few words, _viz_: The strength or force of the gas
from the inflamed composition of a rocket being given, as also the
weight and quantity of the composition, the time of its burning, and
the weight and dimensions of the case and stick, to find the height
to which it will ascend, when projected perpendicularly upwards.
After making the necessary calculation, he concludes by observing,
that, having determined the height of the rocket, and its velocity,
when the composition is just consumed, it follows that its whole
height may be determined in the usual manner by the known formula,
for the ascent and descent of heavy bodies. Another proposition is
that of determining the path of a rocket near the earth's surface,
neglecting the resistance of the air; and among others, for finding
the horizontal range of a rocket, the angle of elevation, and the
time the composition is on fire, being given.

The observations of Mr. Peyre, (_Le Mouvement Igné_,) are confined
principally to the effects of gunpowder; and although applied to the
use of gunpowder, and the theory of its explosive effects, yet there
is nothing in immediate relation with this subject. The generation
of gaseous fluid, and its impelling power, and the consequent recoil
of pieces, predicated in fact on the ingenious experiments and
conclusions of Mr. Robins, may furnish some data on this head. But
the principles of accelerated motion, on which the effective power of
war-rockets depends, this accelerated motion being no other than the
acquired velocity of their recoil, necessarily involves a question of
a different kind from that of common projectiles.

The _caduceus_ rocket has not much more than half the power of
ascension as the single rockets; because, being composed of
two rockets placed at an angle of 90 degrees, with the usual
counterpoise, (the stick), it forms in its flight a serpentine motion
resembling two spiral lines, or double worm; and although by reason
of the stick it ascends vertically, yet the great resistance it meets
with from the air, in consequence of this motion, causes its flight
to be considerably retarded.

On the contrary, when rockets are fixed one on the top of another,
called _towering rockets_, their effect is not at all diminished;
for they experience no additional resistance, as the small rocket is
placed in the head of the large one; and when the latter arrives at
the maximum of elevation, it communicates fire to the former, which
then rises as far beyond the first, if not higher, in consequence of
the pressure of the atmosphere being less, as it would, if discharged
by itself on the ground. Sky rockets, however, which are merely
placed on one stick, do not, unless so required, act in this manner.
Although two, three, or more, may be so arranged, yet the intention
is nothing more than to combine their effect, so that their tails may
appear as one stream of fire. Nevertheless, they may be so arranged,
as that when one is consumed, another may take its place, and produce
a new volume of fire, and, in this case, they would mount to a great
height.

_Tourbillons_, usually called the common or table _tourbillons_,
which receive their name from the whirling motion they take in
their flight, produce also, by the arrangement of their cases, and
the cross stick which serves as a balance, a horizontal and rotary
motion; and while one part of the fire serves to elevate them,
another part, issuing in a horizontal direction, but at opposite
sides and extremities, gives to the tourbillon a wheeling motion. The
mosaic tourbillons are of a different kind, and intended for another
effect. Tourbillons of this kind preserve a regular and constant
motion.

The _mosaic candle_ owes its effect, in a great measure, to the
rocket composition. Using alternately, composition, meal-powder,
and a star, ramming the composition sufficiently, but not so as to
break the stars, a case is formed, the effect of which is brilliant
and striking. Besides the rapid combustion of the composition, the
stars, when the fire comes to the meal-powder, are thrown out by it
in succession, and to the height of one hundred and more feet. We
have also, in this instance, the effect of the rocket composition,
and that of gunpowder; the last of which, acting in the case in the
same manner as powder in a musket on a ball, throws the stars to a
great height. Hence the _effect_ is varied according to the manner
of loading the case; and by employing alternately the substances
we have mentioned, the effects follow in regular succession. The
use of gunpowder in this manner, is strikingly shown in many other
fire-works. When, for instance, stars, serpents, &c. forming the
furniture of a rocket, are to be dispersed, gunpowder is put in the
head or conical cap of the rocket, and fire is communicated to it at
the moment the rocket has arrived at its extreme elevation. In the
bursting of paper shells, the same effect ensues, and the different
substances contained in the shell are dispersed in every direction.

Balloons are nothing more than shells made either of paper, or
wood turned hollow. These balloons are discharged from mortars,
or fire-pots, sometimes called pots of ordnance. They are merely
cylinders of various diameters, made of paper and very thick, or
of metal, and are furnished at their bottom with a conical cavity
lined with copper, designed to hold the charge of powder. When the
balloon is filled, (see _Balloons_), it is introduced into the
mortar over the charge, and being furnished with a fuse as in other
shells, takes fire the moment the powder is inflamed. According
to the quantity of powder made use of, so will be the height of
ascension. By determining the ascension, and the time required for
the fuse to burn, and communicate fire to the shell, we may fix the
precise moment for its explosion. The powder contained in the shell
is sufficient only to burst it, and disperse its contents. (See
_Mortars_, _Fire-pots_, and _pots of Aigrette_.)

A balloon will contain more stars, serpents, &c. than the head of an
ordinary rocket, and the effect which they produce, must of course
be more striking. The Congreve rocket, calculated as it is to convey
carcass composition, balls, grenades, &c. if furnished with stars,
crackers, &c. would produce an effect equal, if not superior to the
balloon.

We remarked, that, in common sky rockets, the charges consist of a
mixture of gunpowder, saltpetre, and charcoal, with occasionally
other additions, as steel-filings. _Rocket-stars_, on the contrary,
are usually formed of mealed powder, saltpetre, sulphur, and
sometimes other substances according to the colour of the flame
required. Thus, for the _white star_, composition oil of spike, (a
preparation of Barbadoes tar, and spirit of turpentine), and camphor
are employed; the camphor giving to the flame a white appearance. The
_blue stars_ owe their colour to sulphur, which is in the proportion
of one to four of the meal-powder; the _variegated stars_ have the
same materials, with sulphur vivum, and camphor; and the _brilliant
stars_, _common stars_, and a variety of others, we shall mention
in their proper places, are all formed by the addition of sundry
substances.

The variety of _rains_, as _gold rain_, _silver rain_, &c. are
differently prepared. Besides saltpetre, meal-powder, and sulphur,
gold rain contains in its composition the filings of brass, saw-dust,
and pulverized glass. In this instance, the saw-dust communicates
colour, while the brass and the glass are thrown out, the former
partly consumed, and the latter partially fused by the intense heat.
The same effect may be produced by meal-powder, saltpetre, and
charcoal, or saltpetre, sulphur, antimony, brass filings, saw-dust,
and pulverized glass. Here the antimony, as well as the brass,
communicates the golden colour. (_See antimony._) Silver rain is
generally formed of saltpetre, sulphur, meal-powder, antimony, and
sal prunelle, but without saw-dust; the antimony communicating silver
brilliancy to the flame. It may also be formed, by employing, in
given proportions, saltpetre, sulphur, and charcoal, the particular
effect depending upon the proportions; or by using antimony in lieu
of the charcoal, or in the place of the antimony, steel-filings.
Whether antimony or steel-filings are used, the effect of their
combustion is the same, forming in the one instance, an oxide of
antimony, and in the other, an oxide of iron. Both gold and silver
rain is employed chiefly for sky-rockets. As to the colours required,
they may be formed of other substances.

The charges for _water-rockets_ are also various. In some of which,
besides the usual ingredients, (meal-powder, saltpetre, and
sulphur,) sea-coal, steel-filings, saw-dust, &c. enter into their
composition.

As to the different compositions, it will be sufficient to remark,
that for _wheels_, _fixed cases_, _sun cases_, _gerbes_, _Chinese
fire_, _tourbillons_, _water balloons_, _water squibs_, _serpents_,
_port-fires_, _cones_, _globes_, _air-balloon fuses_, _fire-pumps_,
and many others to be noticed hereafter, the basis of them is either
gunpowder or saltpetre, and sulphur and charcoal, with or without
additions. With respect to the composition of the stars of different
colours, it is to be observed, that the particular colour is given
by pulverized cast-iron, steel-filings, camphor, amber, antimony,
perchloride of mercury, (corrosive sublimate), ivory-dust, copper,
frankincense, &c. To produce _tails of sparks_, pitch or rosin is
added. Stars which produce _some_ sparks are usually made by using
gum water in mixing the composition. The gum appears to produce
a separation of the inflammable substances, and, as it is not
combustible, to check, as it were, the rapidity of the combustion. In
some preparations, also, isinglass or fish-glue is used in solution.
This, no doubt, acts in the same manner, as well as to give firmness
to the composition; but its solution is also used as a vehicle. On
the same principle also, we learn the use of caustic ley, quicklime,
&c. in preparing match-rope. After soaking the cord in a solution
of nitre, it is afterwards dipped into ley, which is nothing more
than a solution of potash rendered caustic by means of quicklime.
The potash evidently checks the combustion. The formulæ for slow
match, are, however, various. In the match-wood, also, prepared from
the wood or bark of the linden, the wood is usually first soaked in
a solution of saltpetre, and afterwards in a solution of acetate
or sugar of lead, &c. For the same purpose, nitrate of copper is
recommended. For stars of a yellow colour, besides gum arabic, or gum
tragacanth, saltpetre, and sulphur, the addition of powdered glass,
orpiment, (sulphuret of arsenic), and white amber, are occasionally
made. The colour is owing to the amber and the orpiment, which have
the property of communicating it to flame. We may observe, generally,
that the colours produced by different compositions, is a subject of
importance to the pyrotechnist. He should know the properties of each
substance, and the effect of each ingredient; and, with respect to
their action, be able to foretell the appearance of the flame, and
other circumstances connected with the art. As a general example,
we may state, that sulphur gives a blue; camphor, a white, or pale
colour; saltpetre, a clear white yellow; amber, a colour inclining
to yellow; muriate of ammonia, (sal ammoniac), a green; antimony,
a reddish; rosin, a copper colour, and Greek pitch, a bronze, or
a colour between red and yellow. In using these substances, the
following remarks may be useful;--that for producing a white flame,
the saltpetre should be the chief part; for blue, the sulphur;
for flame inclining to red, the saltpetre should be the principal
ingredient, using at the same time, antimony and pitch. (See _matches
of different colours_, in Part ii.)

Coloured flame may be produced by various other substances, many
of which are expensive, and therefore could not be employed
economically. Thus, in fire-works made with hydrogen gas, or
inflammable air, which have a pleasing effect, by forcing the gas,
either from a bladder, oiled-silk bag, or gas-holder, through a
variety of revolving jets, which are so arranged as to exhibit stars,
or through pipes furnished with small apertures, &c. to resemble
different standing figures,--the effect may be varied by previously
mixing the gas with the vapour of ether, and other substances, which
communicate to the flame, particular colours, which, in a darkened
room, are extremely brilliant. Cartwright's fire-works are formed in
this manner. (See _fire-works with inflammable air_.)

Muriate of strontian, mixed with alcohol, or spirit of wine, will
give a carmine-red flame. For this experiment, one part of the
muriate is added to three or four parts of alcohol. Muriate of lime
produces, with alcohol, an orange-coloured flame. Nitrate of copper
produces an emerald-green flame. Common salt and nitre, with alcohol,
give a yellow flame. (See _Illuminations and Transparencies_.)

In addition to the facts already stated, it may be proper to observe,
that the ingredients employed to _show in sparks_, which are rammed
in _choaked cases_, are various, according to the colours required;
as black, white, gray, and red. The black charges are composed
of meal-powder and charcoal; the white, of saltpetre, sulphur,
and charcoal; the gray, of meal powder, saltpetre, sulphur, and
charcoal; and the red, of meal-powder, charcoal, and saw-dust. These
are considered regular or set charges, to which we may add two
others, called compound and brilliant charges. The compound charges
contain a variety of substances which afford sparks; and hence,
besides the usual inflammable bodies, saw-dust, antimony, steel and
brass-filings, are used. The brilliant fires owe their particular
effect to the presence of steel-filings, or pulverized cast-iron.
Iron, in any of its states, when minutely divided, has the same
effect.

Quick match is usually formed of cotton, by soaking it in a solution
of nitre, and adding meal-powder. A solution of isinglass is
sometimes used. The etoupille of the French is of the same nature.
The manner, quick and slow match, &c. are prepared, with the various
formulæ, will be considered under their respective heads. Touch
paper, for capping serpents, crackers, &c. will also be noticed. The
pyrotechnical spunge owes its inflammability to nitre.

In the various composition of aquatic fire-works, although more
care and attention are required, it is to be observed, that, in
forming water-rockets, horizontal wheels, water-mines, fire-globes,
water-balloons, water-squibs, water-fire-fountains, and the like,
substances are generally used along with the usual ingredients,
which, under particular circumstances, may be said to _repel_, as
well as resist the action of the water; and in this particular
they resemble the celebrated Greek fire, of which we shall speak
hereafter. This remark, however, applies only to certain works. After
the rockets have been filled, their ends are dipped in melted rosin
or sealing-wax, or secured with grease.

Fire-works, usually exhibited in rooms, are made with odoriferous
gums and perfumes, and hence are called odoriferous fire-works.
We may remark, that the odour or perfume is given by a variety of
substances; for these, at a high temperature, are partly consumed,
and partly evaporated. Thus camphor, yellow amber, flowers of
benzoin, myrrh, frankincense, cedar-raspings, and the essential oils,
particularly of bergamot, are employed for this purpose. Scented
fire-works are of the same character. The Italians and the French,
who have made more experiments in Pyrotechny, than other nations,
have improved odoriferous fire-works. In these compositions, they
also employ storax, calamite, gum benzoin, and other substances.
_Scented fire_ was greatly in use in Egypt, Rome, and Athens, at
their fetes and public ceremonies. The unpleasant smell which
gunpowder, sulphur, &c. occasion in a confined apartment, has induced
the modern artificers to add sundry odoriferous substances to their
pyro-mixtures. On this subject, it will be sufficient to observe,
that the _scented vase_, which was in use at Athens, contained the
following substances: storax, benzoin, frankincense, camphor, gum
juniper in grains, and charcoal of the willow. It does not appear
that nitre was employed. The custom of burning frankincense before
the altar, is indeed very ancient; for, in the primitive temple at
Jerusalem, the custom was adopted by the priests in the Sanctum
Sanctorum, and is continued by the Greeks and Armenians, the Jews,
the Turks, the Persians, (especially the followers of Zoroaster),
preserve this custom. The _Holy Fire_ of the latter is nothing more
than the inflamed carburetted hydrogen gas, which comes from the
naphtha ground at Baku.

Besides the use of nitre in pyrotechnical compositions, as it forms
an essential part in all of them, there is another salt we had
occasion to notice, of which an account will be given hereafter,
that affords a variety of amusing experiments. This salt is the
hyperoxymuriate or chlorate of potassa. Although it has neither
been used for fire-works on an extensive scale, nor does it enter
into any of the compositions usually made for exhibition, yet its
effect is not the less amusing. Some general idea may be had of its
effect, by stating a few experiments. If a mixture of this salt and
white sugar be made in a mortar, and the mixture laid on a slab or
tile, and a string wetted with sulphuric acid, (oil of vitriol), be
brought in contact with it, or a drop or two of the acid be let fall
upon it, a vivid combustion will take place. In this experiment, the
acid decomposes the salt, and the oxygen unites with the carbon and
hydrogen of the sugar, and forms carbonic acid and water. The same
salt, rubbed in a mortar with sulphur, will produce a crackling noise
resembling that of a whip; and if a mixture of the two be struck with
a hammer, the percussion will cause a loud detonation. The same thing
happens when phosphorus is used, but the detonation is more violent.
Various other experiments may be made with it. It forms the principal
part of the match, called the _pocket lights_. These are made, in the
first place, by dipping the wood previously cut in splints in melted
sulphur, and afterwards in a mixture of this salt with sugar, which
is moistened with water. The match is then dried. When used, it is
dipped in sulphuric acid. The red colour, usually given to the match,
is formed by mixing with the composition some vermillion. Another
application of the same principle, is the firing of cannon. For this
purpose, after the tube is filled with powder, a covering of the same
mixture is applied when mixed with water. It is then dried. When the
tube is put in the vent, a drop of sulphuric acid will inflame it,
and consequently discharge the gun. This salt also, when mixed with
sulphur, may be used to fire fowling pieces, provided the lock be so
constructed, as in a late invention, that it acts by percussion. (See
Thenard's Priming powder.)

The Rev. Alexander Forsyth of Alexander Forsyth of Belhelvie,
in Aberdeenshire, Scotland, took out a patent for a new kind of
gun-lock, to be used without a flint, and has contrived to inflame
powder merely by percussion. The powder employed for priming,
consists of chlorate of potassa and sulphur. The gun-lock is
calculated for firing cannon as well as musquetry; it is contrived
to hold forty primings of such powder; and the act of raising the
cock primes the piece. Each charge of priming is supposed to contain
one-eighth of a grain of the salt. There are other substances which
also produce fire by percussion. The fulminating silver, mixed with
any substance, or used by itself, will detonate by percussion. It
should be used with great caution. A grain or two will explode with
great violence. (See _Detonating Works_, _Waterloo crackers_, _&c._)

There are several other metallic preparations which detonate
violently, such as the fulminating gold, fulminating mercury, &c.
all of which must be used with extreme caution. (See the respective
articles.)

_Sec. IV. Of Illuminations._

Although nothing of much importance can be said on the subject of
illumination, yet at the same time, as it is connected with some
remarks we will hereafter offer, it may be proper to observe, that
the practice of illuminating, as well as the exhibition of fire-works
in public rejoicings, has been in use for many years. The former
indeed has been customary for many centuries. We have, however,
appropriated an article to the manner of forming illuminations and
transparencies, and also on imitative fire-works.

Illuminations, whether with lamps, candles, flambeaux, &c. may be
rendered more impressive from the manner of their arrangement. In
some instances different coloured flames have been used; and the
effect in this case is more grand and beautiful.

The public lighting of cities on festivals, and particularly on
joyful occasions, called illuminations, is of great antiquity.
Indeed, illuminations are a general expression of the public feeling,
and should, on important occasions, be encouraged. Victories gained
over an enemy by the army or navy are subjects of rejoicing. While,
in such cases, illuminations may be viewed as an _expression_ of the
feelings of the people, they serve moreover to stimulate, in the
spirit of the _amor patriæ_, the future actions of the patriot and
the soldier; and while such rejoicings are demonstrative of victory,
they are equally expressive of that virtuous feeling, of which every
one must partake, on the return of an honourable peace.

What could have been more impressive than the brilliant
spectacle exhibited in Paris in 1739, on the return of peace?
Besides illuminations, the fire-works on that occasion were truly
magnificent. The same may be said of those at Pont Neuf, and those
at Versailles in the same year. We shall have occasion to speak of
them, when we come to the arrangement or the order of fire-works for
exhibition.

The Egyptians at an early period, made use of illuminations, and
particularly at a festival, which is mentioned by the Greek authors.
During the festival, as Herodotus says, lamps were placed before all
the houses throughout the country, and kept burning the whole night.

During the festival of the Jews, called _festum encæniorum_, the
feast of the Dedication of the Temple, the lamps were lighted
before each of the houses, and the festival continued eight days.
Illuminations were also used in Greece, according to a passage in
Æschylus. When games were exhibited in the night-time at Rome, the
forum was lighted. Caligula, on a similar occasion, caused the city
to be illuminated. In honour of the great orator Cicero, as he was
returning home at night, after the defeat of Cataline's conspiracy,
lamps and torches were lighted in all the streets. Byzantium,
afterwards Constantinople, was ordered to be illuminated with lamps
and wax candles on an Easter eve, in the time of Constantine.

That this custom was prevalent among the christians in the first
century, is evident from many authors. Professor Beckman, in his
_History of Inventions_, vol. iii, p. 383, says, that "the fathers of
the first century frequently inveigh against the christians, because,
to please the heathens, they often illuminated their houses, on
idolatrous festivals, in a more elegant manner than they. This they
considered as a species of idolatry. That the houses of the ancients
were illuminated on birth-days, by suspending lamps from chains, is
too well known to require any proof."

At Damascus, the Turks always keep a lamp burning over the tomb, as
it is called, of Ananias, which they much reverenced. It is said
to be in the same house in which St. Paul lodged with Judas. (See
_Maundrel's Travels from Aleppo to Jerusalem_.)

Lamps, according to Dr. Pococke, are kept continually burning in the
Jewish synagogue at Old Cairo, said to have been built about sixteen
hundred years ago. (See _Pococke's Travels through Egypt_.)

In Persia, lamps are kept burning in consequence of some religious
notion, and particularly at the sepulchre of Seid Ibraham. (See
_Travels through Muscovy into Persia_.)

A lighted lamp is frequently put up in Persia as a mark to shoot
at. To be a good shot, the marksman must extinguish it. At the
celebration of the feast called Ashur or Ten, from its lasting ten
days, which is kept in memory of Hossein, the youngest son of Hali,
the Persians make use of rags dipped in suet and naphtha, and burn
them in lamps; and their courts are lighted up with thousands of
lamps, the light from which is increased by as many more lanterns
made of paper, that are fastened to cords drawn across the court.

The Chinese, in celebrating their solemn feasts, especially on the
15th day of the first month, called the Feast of the lanterns, from
the multitude and grandeur of the lamps they exhibit in the evening,
are remarkable for the splendour of their exhibitions. We are
informed, (_A Description of China, &c._), that many of the grandees,
retrenching every year something from their tables, apparel, and
equipage, to show the greater magnificence in the lanterns, used on
this occasion, expend the sum of 2000 crowns. The largest are about
twenty feet in diameter, and are lighted by an immense number of wax
candles and lamps; but those that are most common, are of a middling
size. These are generally composed of six faces, or panes, each of
which has a frame of varnished wood, adorned with gildings four
feet high, a foot and a half broad, covered on the inside with fine
transparent silk, on which are painted flowers, trees, rocks, and
sometimes human figures. The painting is very curious, the colours
lively, and the wax candles give the painting a beautiful splendour.
These six pannels joined together, compose a hexagon, surmounted at
the extremities by six carved figures, that form its crown. Around it
are hung broad strings of satin, of all colours, with other silken
ornaments, that fall upon the angles without hiding the light of the
pictures. The feast of the lanterns is also celebrated by bonfires
and fire-works.

Candles are also used for the same purpose. Chandeliers, differently
made, and holding a greater or smaller number of candles, add greatly
to the effect.

The candles used by the natives of Otaheite are curiously made.
According to Cooke, (_First Voyage, &c._), they have candles made of
a kind of oily nut, which they stick one over another upon a skewer
thrust through the middle of them. The upper one being lighted, burns
down to the second, at the same time consuming that part of the
skewer which goes through it; the second, taking fire, burns in the
same manner down to the third, and so of the rest. These candles give
a tolerable light, and some of them will burn a considerable time.

The lighting of streets, Beckman considers in some respects to be a
modern invention, and after quoting various authorities concludes,
that, of modern cities, Paris was the first that followed the example
of the ancients by lighting its streets. It appears, therefore,
that the practice of illuminating was reserved by the ancients
for some great occasion, that lighting of the streets was more or
less partial, and confined to particular places, and that it was
not general without some particular occasion called for it. (See
_Illuminations_.)

Kircher, the German philosopher, had a wick made of amianthus,
which burnt for two years without injury, and was at last destroyed
by accident.[8] The Greenland stone flax, which is the same as
amianthus, the Rev. Mr. Edge says is used in Greenland for lamp
wicks, and burn without being in the least wasted, whilst supplied
with oil or fat. Ellis (_Voyage for the Discovery of a North-West
Passage_), found the mountain flax, (asbestus), among other minerals,
on the Resolution Islands, inhabited by the Esquimaux, which is
used for similar purposes. We may remark here, that the Esquimaux
use stone for lamps, which they hollow out, and, according to
circumstances, use also dried _goose dung_ for wick.

_Sec. V. Of some of the Feats or Performances by Fire._

We introduce this subject to show, that certain kinds of fire-works
have been employed for the purpose of deceiving the ignorant, and
amusing the better informed part of mankind. Many of the tricks of
jugglers and slight-of-hand men, and the performances of certain
rites, particularly by the ancient magi, and pagan priests, come
under this head. Sundry substances, in connection with artificial
fire, have been employed by persons of this description. It is true,
our account of them is rather imperfect. Had the works of Celsius,
which he wrote against the ancient magi, been preserved, we would,
no doubt, have been better acquainted with the art of the ancient
conjurors and jugglers.

Professor Beckman has endeavoured to trace the origin of the
necromantic art; but although of opinion that it is very ancient, and
founded in superstition and unnatural causes, he is of opinion, that
the works of Celsius, which are lost, were full on the subject, and
for that reason our account must be imperfect.

Plain common sense, but with enlightened reason, has alone convinced
mankind of the follies of older generations, and of relying on
superstitious ceremonies, or believing in miracles, exorcism,
conjuration, necromancy, sorcery, or witchcraft.

The torch of reason, and experimental philosophy have dispelled
the clouds of ignorance and superstition; and men, becoming more
enlightened as they progress in the investigation of truth, are no
longer under the influence of false doctrines, or led away by a
bigoted priesthood. Philosophical experiments, the various optical
illusions, the effects of electricity, magnetism, &c. are founded on
immutable truths, which become the more familiar as we progress in
science.

Truth, however, although elicited by the genius of great men, who
have lived in every age, was suffered to be brought to the rack;
because it either militated against the views of the priesthood, and
enlightened the people, or curtailed the ecclesiastical power and
authority of the church.

Because Anaxagoras taught that the sun and stars were not deities,
but masses of corruptible matter, he was tried and condemned in
Greece. Accusations of a similar nature contributed to the death of
Socrates. Copernicus, in consequence of the threats of bigots and the
fear of persecution, was prevented from publishing, during his life
time, his discovery of the true system of the world; and it is well
known, that the great Galileo was imprisoned a year, and then obliged
to renounce the motion of the earth, because he asserted it. In 1742,
a commentary on Newton's _Principia_, one of the first productions of
human genius, was not allowed to be printed at Rome, in consequence
of its promulgation of this doctrine; and, in the true spirit of
_priest-craft_, the commentators were obliged to prefix to their work
a declaration, _that on this point, they submitted to the decisions
of the supreme pontiffs_! Such are the results of bigotry, ignorance,
superstition, and especially of civil and ecclesiastical governments,
that consider learning a curse, and ignorance a blessing! Happily
for the people of the United States, their co-equal rights and
enlightened reason, will ever guarantee them against tyranny on the
one hand, and fanaticism on the other. Superstition has always been
an engine of oppression, and wherever it prevails, the powerful are
sure to make use of it to oppress and destroy the weak.

Another instance of the assumed prerogative of the holy fathers
may be found in their conduct towards the house of Medici; for the
pontiffs, it is known, induced the house of Medici, by granting it
the cardinalship, to suppress the academy del Cimento. The reason
of this step is obvious to all; for they were sensible, that, if
the people became once enlightened, they would lose their weight,
their influence, and authority. But as jugglers are conscious of
their gross deceptions, working on the imagination and credulity
of the multitude, they in this respect appear at least to know
themselves. Like the juggler mentioned in Xenophon, who requested the
gods to allow him to remain in places, where there was much money
and abundance of simpletons, they acted as the prototype. We might
enumerate, if it were not irrelevant to our subject, a number of
facts concerning these impostors.[9]

The miracles wrought by Moses, as recorded in the books of Exodus,
were, we have reason to believe, by the immediate command of a
supreme power. When Moses had commissioned Aaron (_Exodus_, chap.
vii, verse 9, 10, &c.) to be a prophet, Aaron took a rod and cast
it before Pharaoh and his servants, and it became a serpent; but it
seems, however, that Pharaoh called the wise men and the sorcerers,
called the magicians of Egypt, who performed the same thing with
their enchantments; "for they cast down every man his rod, and they
became serpents: _but Aaron's rod swallowed up their rods_." It
appears that on another occasion, the waters were turned into blood
by smiting them with the rod; "and the magicians of Egypt did so
with their enchantments." When Aaron was commanded to stretch forth
his hand with his rod over the streams, &c. frogs appeared upon the
land, and the magicians did so likewise; but when vermin were brought
forth, by smiting the land, the magicians were unsuccessful, and said
unto Pharaoh, "_This is the finger of God_." In the continuation of
the plague, Moses and Aaron were commanded to take the ashes of the
furnace, before Pharaoh, and sprinkle them up towards Heaven; and
it became a hail on man and beast, but the magicians were affected,
and could not stand before Moses. When Moses stretched forth his rod
towards heaven "hail, and fire mingled with hail," came down; and
on another occasion, they brought forth locusts. When this plague
ceased, Moses caused darkness to prevail.

We will merely observe, that, with regard to the magi of Egypt,
who it is known possessed all the learning of the day, and were
celebrated in after ages for superior wisdom, so much so that
many of the Grecians resorted there to be initiated into their
mysteries,--they were of a different description from those who
really worked miracles, according to divine inspiration. Hence we
find, that, although distinct in their character, the magicians
of Egypt pretended to perform certain rites, and to work upon
the feelings of the people. Their initiary process, which the
Pythagoreans in many respects pursued, and traces of which are extant
in the order of free-masonry, was merely intended to preserve their
knowledge within the pale of, and veiled in, hieroglyphic mystery,
which none but the initiated could understand. Priestley, in his
_Institutes of Moses_, points out the difference between the magi,
so called, and the rites and ceremonies of the ancient Hebrews. But
the imposition practised on mankind, even in modern times, aided by
engines of the most abominable kind, as instruments of torture, in
the inquisitorial tribunals of Portugal and Spain, are sufficient of
themselves to call down the vengeance of impartial justice.

That the magicians were conscious of their inability to work
miracles, is evident from their own declaration; for, after vermin
had been brought forth by Moses and Aaron, they endeavoured to do the
same, and being unsuccessful declared, that _this was the finger of
God_; and many other instances are recorded of their attempts being
altogether abortive. It appears also, that at first they believed
they were able to perform all that Moses had done; and Pharaoh
himself, by calling them together for that purpose, seemed to be of
the same opinion, until he and his servants were finally convinced
that Moses and Aaron wrought such miracles by inspiration. There can
be no relation whatever between Moses and the magicians; for although
he was, if we may judge from biblical history, acquainted with all
the knowledge of the magicians, his mission was altogether of a
different character. Many of the modern Greek and Armenian priests,
in their celebration of the holy fire, palm upon their credulous
followers, a belief, that they possess the power of working miracles,
as will appear from the account we shall give of them. We will not
enlarge on this subject at present, but pass on to consider the more
common performances, which have excited the wonder and admiration of
mankind.

The deception of breathing out flames, which excites the astonishment
of the ignorant, is very ancient. When the slaves of Sicily, about
two centuries ago, made a formidable insurrection, and avenged
themselves in a cruel manner for the severities which they had
suffered, there was among them a Syrian named Eunus, a man of great
craft and courage, who, having passed through many scenes of life,
had become acquainted with a variety of arts. He pretended to have
immediate communication with the gods; was the oracle and leader of
his fellow slaves; and, as is usual on such occasions, confirmed
his divine mission by miracles. When, heated by enthusiasm, he was
desirous of inspiring his followers with courage, he breathed
flames or sparks among them from his mouth while he was addressing
them. We are told by historians, that, for this purpose, he
pierced a nut shell at both ends, and, having filled it with some
burning substance, put it into his mouth and breathed through it.
Some affirm, that he used tow previously soaked in a solution of
saltpetre. The deception at present is much better performed. The
juggler rolls together some flax or hemp; sets it on fire; and
suffers it to burn till it is nearly consumed; he then rolls round
it, while burning, some more flax, and by these means the fire may
be retained in it a long time. When he wishes to exhibit, he slips
the ball into his mouth and breathes through it; which again revives
the fire, so that a number of weak sparks proceed from it; and the
performer sustains no hurt, provided he inspire the air not through
the mouth but the nostrils.

By this art, the rabbi Bar-Cacheba, in the reign of the emperor
Hadrian, made the credulous Jews believe, that he was the hoped for
Messias, and two centuries after, the emperor Constantius was thrown
into great terror, when Valentian informed him, that he had seen one
of the body guards breathing out fire and flames in the evening.

It appears evident from the writings of Herodotus, that the ancients
possessed a knowledge of attracting lightning, or the electric fluids
with pointed instruments made of iron. He informs us, that the
Thracians disarmed heaven of its thunder-bolts, by discharging arrows
into the air; and the Hyperboreans by darting into the clouds, pikes
headed with pieces of sharp pointed iron.

Pliny speaks of a process, by which Porsena caused fire from the
heavens to fall upon a monster which ravaged his country. He mentions
also, that Numa Pompilius, and Tullius Hostilius practised certain
mysterious rites to call down the fire from heaven. What these
mysterious rites were is of no moment; the fact is sufficient.
Tullius, because he omitted some prescribed ceremony, is said to have
been killed by the fire. A similar accident happened in France with
the electrical kite.[10]

For deceptions with fire, the ancients employed a number of
inflammable substances, which they dexterously used; among them,
naphtha, a fine bituminous oil, which readily inflames, was
principally used. (For the effect of _naphtha_, _see_ _Greek
fire_.) Galen informs us, that a person excited great surprise
by extinguishing a candle, and again lighting it without any
other process than holding it against a wall or a stone. This,
Galen observes, (_De Temperamentis_, iii. 2, p. 44.) was effected
in consequence of the wall or stone being previously rubbed
with sulphur, which, however, must have been something more. He
also speaks of a mixture of sulphur and naphtha. If it had been
phosphorus, or some of its preparations, it would appear more
probable.

Plutarch relates the secret effects of naphtha, and observes, that
Alexander was astonished and delighted, when it was exhibited to him
in Ecbatana. Medea destroyed Creusa, the daughter of Creon, with
this oil. This fact is stated by Plutarch, Pliny, Galen, and others,
and believed by Beckman. She sent, it appears, to the unfortunate
princess, a dress covered with it, which burst into flames as soon
as she approached the fire of the altar. The dress of Hercules,
which also took fire, was dipped in naphtha, though said to be in
the blood of Nessus. On the subject of naphtha, Beckman remarks,
"that this oil must have been employed when offerings caught fire in
an imperceptible manner. _In all periods of the world, priests have
acted as jugglers to simple and ignorant people._"

The most ludicrous account of the necromantic art, by which similar
tricks were performed, is that given by Celini, (_Life of Benvenuto
Celini_, a Florentine Artist, by T. Nugent, LL. D. &c.) of a Sicilian
priest, who drew circles on the floor with various ceremonies, using
fire and different perfumes. Having made an opening to the circle,
and thrown perfumes into the fire at a proper time, he observes, that
in the space of an hour and half, "there appeared several legions
of devils, insomuch that the amphitheatre was quite filled with
them." Benvenuto, it seems, at the instance of the priest, asked
some favours of them, which, however, he never realized. At a second
exhibition he held a _pentagorun_, while the priests questioned
the leaders of the demons "by the virtue and power of the eternal
uncreated God," using the Hebrew, Greek, and Latin languages. The
Demons appeared more numerous than at first, and more formidable.
He states that "quivering like an aspen leaf, he took good care of
the _perfumes_," and was directed by the priest "to burn proper
perfumes." This ceremony was continued until the "bell rang for
morning prayers," and the priest "stripped off his gown and took up
a wallet-full of books," declaring, "that as often as he had entered
magic circles, nothing so extraordinary had ever happened to him!"
How is it, in the language of professor Beckman, that "in all periods
of the world, priests have acted as jugglers to simple and ignorant
people?" * * * * *

This same Benvenuto Celini, however, was a man of intelligence.
He wrote a work called the _History of Jewelry_; in which the
first idea of phosphorescent mineral bodies is to be found. This
work was written in the beginning of the 16th century. His life,
although singularly marked, what with popes, priests, artists, and
necromancers, presents a singular retrospect.

What was more absurd, and even profane, than the tricks of Joseph
Balsamo, called Il Conte Cagliostro, who with Schœpfer, revived
the study of the magical arts; and who with invocations, friction,
fumigations, and optical deceptions astonished the ignorant of their
day. Whether like Æneas, in his descent to hell, they made their way
with their falchions through crowds of ghosts, or like Dioscorides,
relied on the efficacy of herbs, or like Paracelsus, carried an evil
spirit in their canes, or wore a _jewel_ like Shakspeare's toad,
which possessed marvellous virtues, or employed the magic stone
(_agate_) of the east, and invoked their _urim and thummim_,--it
is certain they worked upon the imagination of the people. By the
application of _conium maculatum_, (hemlock) consisted the ceremony
of ordaining a Hierophant; by the hartshorn of Orpheus, they had a
divine remedy for the passions of the body; and by a mixture of _new
mustard and olive oil_, they could produce a symphony, which invoked
the spirits, and, Pythonesis like, declare to the people, that they
"_had devils in their bellies_!!"

Of the phial of Cagliostro, Cardan relates that he had this phial
twice exhibited to him, and complains bitterly of having seen
nothing, after the anthem _Sancte Michael_, but some bubbles
that issued from the bottom, though it was believed that these
bubbles were angels! He says, "_Nihil tamen omnino vidi poste
hanc invocationem nisi bulas pauculas quasdam ex imo gutti fundo
exæstuantes_." Aulus Gellius and Hero mention tricks of this
kind practised by the Egyptians. Roger Bacon, the alchymist, was
excommunicated by the pope, and imprisoned ten years, for supposed
dealings with the devil.

Equally absurd to a man of reflection, are the observations of
antiquated writers on spontaneous generation, by heat. Borello
(_Physical History_) tells us, "that fresh water craw fish may be
regenerated, by their own powder, calcined in a crucible, then boiled
in water with a little sand, and left to cool, for a few days; when
the animalcula will appear swimming merrily in the liquor, and must
be then nourished with beef blood, till they attain the proper
size to stock your ponds with."[11] The Sieur Pogeris and M. de
Chamberlan, both agree with Signior Borello, but, in the chemistry of
the matter, they add that the operation must be performed, _during
the full of the moon!_ If this _lunar system_ be adopted, would not
the _crab_ also, have been a more favourable _sign_ to have ruled the
nativity of _craw fish_?

Swift, however, alludes to these agencies, fallacious as they are, in
the following lines:

"So _chymists_ boast they have a power,
"From the dead ashes of a flower,
"Some faint resemblance to produce,
"But not the virtue, taste, or juice."

Rochos, equally absurd with Borello, says, in _The Art of Nature_,
that the ashes of _toads_ will produce the very same effect, as the
powder of _crabs' eyes_! Reasoning upon that ridiculous and unnatural
principle of Cæsalpinus, in his comment on Aristotle, _Quæcumque ex
semine fiunt, eadem fieri posse sine semine_, the procreation of eels
from rye-meal, or mutton broth was predicated.

_Julius Camillus_, however, would out-do nature herself; for _Amatus
Lusitanus_ affirms, that he has seen his phials full of _homunculi_
complete in all their parts! Paracelsus (_De Rerum Natura_,) had the
same and many other absurd notions. What, we may truly say, has not
been palmed upon the world, when we are told, that the following
translation from a Hague Gazette, which appeared in the _British
Evening Post_, No. 1645, contained facts, which were confidently
believed by the ignorant:

"Mr. Tunestrick, by origin an Englishman, has just exhibited at
Versailles, a very singular experiment. He opened the head of a
sheep, and a horse from side to side, by driving a large iron wedge
into the skull, by means of a mallet; drew the wedge out afterwards,
with pincers, and recalled the animals to life, by injecting through
their exterior aperture with a tin syringe, a spirituous liquor of
his own composition, to which he attributes surprising effects!
The taste of this liquor resembles that of _Commandus Balm_!!" The
remarkable effects of galvanism, however, are well authenticated;
but _resuscitation_, notwithstanding all apparent life, has in no
instance, to our knowledge, been effected. (See Ure's _Chemical
Dictionary_, article Galvanism.)

Among other tricks, we may mention those with serpents, especially in
the East Indies, and neighbouring islands, where a certain class of
people exhibit them for money.[12]

Persons who could walk over red-hot coals, or red-hot iron, or who
could hold them in their hands and their teeth, are frequently
mentioned. In the end of the 17th century, Richardson, an Englishman,
was a great adept in this performance. We are assured he could chew
burning coals, pour melted lead upon his tongue, swallow melted
glass, &c; but the fact is incredible.

It is true, that the skin may be prepared in such a way as to become
callous and insensible against the impression made on the feet
and hands. It may be rendered as firm as shoes and gloves. Such
callosity may be produced, if the skin is continually compressed,
singed, pricked, or injured in any other manner. Beckman relates,
that in 1765, he visited the copper-works at Awestad, when one of the
workmen, for some money, took some of the melted copper in his hand,
and after showing it, threw it against a wall. He performed a variety
of other experiments with the melted metal.

The workmen at the Swedish melting-house have exhibited the same
thing to some travellers in the 17th century. The skin is first
rendered callous by frequently moistening it, as Beckman says, with
sulphuric acid; and also, he remarks, by using the juice of certain
plants. The skin must also be rubbed frequently, and for a long time,
with oil. Haller, in his _Elementa Physiologica_, V. p. 16, speaks of
this fact.

The manner of rendering the hands callous, or insensible, so that
they may take up, and hold, ignited iron, charcoal, or other
substances, may be seen in an English publication of 1667. The
_Journal des Savants_, of 1677, contains the secret. "It consists
in applying to the hands, various pastes, with spirits of sulphur,
(sulphuric acid,) which destroys the epidermis, &c. and the nervous
energy." This corroborates the account by Beckman. We read that
Richardson had prepared his tongue in such a manner, that he could
hold on the point of it a live coal, covering it first with pitch,
rosin, and sulphur, and could hold a piece of ignited iron between
his teeth. After showing the coal on his tongue, he would then
extinguish it in his mouth. The _Mémoires de l'Académie_ state, that
a person who is salivated can put a live coal in his mouth. The
_Dictionnaire de l'Industrie_ observes, that the sulphur diminishes
the heat of the coal, for the flame is less hot than a candle; and
that the flame of a combination of pitch, rosin, and sulphur, is
still less hot, and by no means so considerable as we would imagine.
In the experiment, the rosin is not melted, and the flame of the
sulphur is inconsiderable. M. Gallois observes, that he witnessed in
the Swedish iron founderies, the men hold melted cast iron in their
hands, doubtless having them previously prepared.

The traces of this art may be found in the works of the ancients. A
festival was held annually, on Mount Soracta, in Etruria, at which
the Hirpi, who lived not far from Rome, jumped through burning coals,
and on this account had certain privileges granted them by the Roman
Senate.

Women also, we are informed, were accustomed to walk over burning
coals, at Cartabola, in Cappadocia, near the temple dedicated to
Diana. Servius remarks, that the Hirpi did not trust to their
sanctity so much as they did to the preparation of their feet for the
operation!

With respect to the ordeal by fire, which it seems was performed in
several ways, one was, that when persons were accused, they were
obliged to prove their innocence by holding in their hands red-hot
iron. This mode of exculpation, as it is called, was allowed only to
weak persons, who were unfit to wield arms, and particularly to monks
and ecclesiastics, to whom, for the sake of their security, the trial
by single combat was forbidden. In Grupius' learned dissertation, in
the German, p. 679, as quoted by Beckman, we read, that the trial
itself took place in the church, under the inspection of the clergy;
mass was celebrated at the same time; the defendant and the iron,
were consecrated, by being sprinkled with holy water; the clergy
made the iron hot themselves; and they used all these preparations,
as jugglers do many motions, only to divert the attention of the
spectators. It was necessary that the accused person should remain
at least three days and three nights, under their immediate care,
and continue as long after. They covered their hands both before and
after the proof; sealed and unsealed the covering: the former, as
they pretended, to prevent the hands from being prepared by art; and
the latter to see if they were burnt.

Some artificial preparation was undoubtedly necessary, or why
prescribe three days for the defendant, who, if they wished to make
him appear innocent, had a certain preventive against the actual
cautery? The three days allotted, after the trial, were requisite, in
order to restore the hands to their natural state. The sacred sealing
secured them from the examination of presumptuous unbelievers.

When the ordeal was abolished, it no longer was kept secret. In
the 13th century, an account of it was published by a Dominican
Monk, Albertus Magnus. In the work of this author, entitled, _De
Mirabilibus Mundi_, he has given the receipt for the composition. It
seems that it consisted in covering the hands with a kind of paste,
and not by searing them. The sap of the althæa, or marsh mallow, the
mucilaginous seeds of the fleabane, together with the white of an
egg, were mixed, and by applying this mixture, the hands were as safe
as if they had been secured by gloves. The use of this mixture, for
the same purpose, may be traced back, it is said, to a pagan origin.
In the Antigone of Sophocles, the guards, placed over the body of
Polynicus, which had been carried away and buried, contrary to the
orders of Creon, offered, in order to prove their innocence, to
submit to any trial: "We will," said they, "take up red-hot iron in
our hands, or walk through fire."

The ordeal, by heated ploughshares, was common in England. It seems,
according to English History, that queen Emma had charges preferred
against her, by Robert, archbishop of Canterbury, for consenting to
the death of her son Alfred, and preparing poison for her son Edward,
the Confessor. She claimed, by the law of the land, the ordeal, or
trial, by burning ploughshares. She passed the nine ploughshares
unhurt, which established her innocence, and caused the archbishop
to fly the kingdom. The chief trials, by ordeal, appear to have been
by fire, water, walking blindfold among heated ploughshares, and
swallowing consecrated bread, which last was introduced about the
time of pope Eugene. The custom was borrowed from the Mosaic law. An
example of its practice occurs in the New Testament, in the story
of Ananias and Sapphira; and the remembrance of it, as Blackstone
remarks, still subsists among common people, as "_May this morsel
be my last_;" "_May I be choked if it is so_," _and the like_; for
it appears, that this ordeal was a piece of bread of about an ounce
in weight, blessed by the priest, and given to the accused person,
who was to try and swallow it, praying that it might choke him if he
were guilty. The bible-ordeal, and the drowning-ordeal, are familiar
to every one, degrading as they all must have been to human reason,
and enlightened principles. Fox, in his _Book of Martyrs_, speaks of
various ordeals, as well as the cruel deaths, and inhuman punishments
inflicted, by the hand of bigotry, and fanaticism, under the cloak
of religion, which were nothing more than a base and impious
prostitution of its genuine principles.

Even among the modern Greeks, the same superstitious notions prevail.
Almost every cavern about Athens has its particular virtues, and is
celebrated for various things; and the offerings, made by Grecian
women, to the _destinies_, in order to make them propitious to their
conjugal speculations, are equally absurd. These offerings, by which
they are to work a miracle, consist of a cup of honey and white
almonds, a cake on a little napkin, and a _vase of aromatic herbs,
burning and exhaling an agreeable perfume_. We are told, however,
that those evil spirits, whose assistance is invoked, for vengeance
and blood, are not regaled upon cakes and honey, but on a piece of
a priest's cap, or a rag from his garment, which are considered as
the most favourable ingredients for the perpetration of malice and
revenge. When a person is _hated_, another absurd custom is used,
which is supposed to be followed by dreadful results. It consists
in placing before his door, a log of wood, burnt at one end, with
some hairs twisted round it. "This curse," says Mr. Dodwell, in his
_Classical Tour_, "was placed with due solemnity, at the door of the
English agent, Speridion Logotheti, while I was at Athens; but he
rendered it of no avail, by summoning a great number of priests, who
easily destroyed the spell, by benediction, frankincense, and holy
water!" This story is much in character with that of the exorcism
of rats, caterpillars, flies, and other insects, an old ritual of
the papal church, performed between the feasts of Easter and the
Ascension. A priest who resided at Bononia, performed the ceremony.
"I went," he says, "to exorcise the insects in that country,
accompanied by a curate, who was a droll fellow, and laughed at the
credulity of the people, while he pocketed their money." It appears,
however, that in all superstitious ceremonies, _fire_, under some
form, was a pre-requisite; but _ecclesiastical fire-works_ we leave
within the pales of the priesthood.

The author of the _Dictionnaire de l'Industrie_, vol. iii, speaks of
a trick, performed with a loaded musket and ball, which, although
apparently inconsistent, is nevertheless true, if we consider the
action of gunpowder equal. This _trick_ is stated to be the firing of
a musket, loaded with ball, at a person, without wounding, or in any
way injuring him.

By taking a ball of solid lead of a smaller size than the calibre of
the musket, and placing it on the charge in a gun, and as much or
nearly so of powder, _over the ball_, the effect we are assured is,
that when the gun is fired, the ball will pass out without any very
sensible force, and even drop a few yards from the gun, although the
report will be as great as if the charge and ball had been used in
the usual manner. This trick is often performed by jugglers, to the
great astonishment of the spectators. The mode of _catching a cannon
ball_ is also of the same character.

The proper charge of powder for the cannon, is divided into two
unequal portions, the lesser of which is placed in the gun as a
charge; the ball is placed on it in the usual way, and the rest of
the powder (by much the greater portion,) placed over the ball, the
lesser quantity being not more than a twelfth part of the whole. A
cannon, so charged, will not project the ball more than 20 yards,
where it might be caught with safety.

Any person who has been in the custom of shooting, must have
frequently observed, that when the shot happens to be mixed with the
powder, its range is impeded; and, under similar circumstances, they
have even been found only a few yards from the muzzle of the piece.
This fact I have witnessed, although I confess I never once reflected
on it.

As to the explanation of this phenomenon, it appears, that it can
only be accounted for by referring to the action of two opposite
forces, mutually repelling each other, added to that of the charge
under the ball; hence, the _reaction_ would be equal, if, under the
same circumstances, both charges were alike situated: but the effect
of the first charge is so much weakened by the counter effect of the
second, that the projectile force of the ball becomes comparatively
nothing.

There is another trick very often performed, which, however chemical,
is not looked upon in that light, neither do performers attempt to
explain it; we mean the exhibition of the _Glace Inflammable_ of the
French.

The preparation is made in the following manner: melt some spermaceti
over a fire, and add a sufficient quantity of spirit of turpentine,
and blend them together. The mixture when cold, will become solid,
having somewhat the appearance of ice. If made in hot weather, the
vessel containing the melted substances must be immersed in cold
water. It does not, we are told, remain in a solid state any length
of time.

It floats more or less in the fluid, which of course is the spirit of
turpentine. The trick, with this preparation, after having put some
of the solid and fluid substance together on a plate, is to pour upon
it concentrated nitric acid, or a mixture of eight or ten parts of
nitric acid, and two of sulphuric acid; inflammation ensues. It is no
other in fact than accension of the oil of turpentine; the addition
of the spermaceti is altogether secondary, and its effect, if any,
must retard instead of promoting the combustion of the turpentine.
The art of making this preparation is in rendering the essential oil
solid and transparent, without altering its inflammable properties.

There is another trick performed, by burning a thread, to which an
ear-ring is tied, and which, notwithstanding the thread is reduced
to a cinder, still holds the ring. This is what the French call the
_Bague suspendue aux cendres d'un fil_. The string is first prepared
by soaking it for 24 hours, in a solution of common salt, and drying
it; then tying it to a ring, and setting it on fire, avoiding any
vibration or oscillation of the string. It is obvious that the salt
serves to render the cinder cohesive.

We have an account in Maundrel's _Travels from Aleppo to Jerusalem_,
of the office of the _Holy Fire_. The ceremony is kept up by the
Greeks and Armenians, from a persuasion that every Easter eve, a
miraculous flame descends from heaven into the holy sepulchre, and
lights all the lamps and candles, as the sacrifice was consumed at
the prayers of Elijah.

"On our approaching the holy sepulchre," says Maundrel, "we found
it crowded with a numerous and distracted mob, who made a hideous
clamour; but with some difficulty pressing through the crowd, we got
up in the gallery next to the Latin convent, where we could have a
view of all that passed. The people began, by running with all their
might, round the holy sepulchre, crying out 'huia,' which signifies,
'_This is he_,' or, '_This is it_.' After this, they began to perform
many antic tricks: sometimes they dragged one another along the floor
round the sepulchre; sometimes marched round with a man upright
upon another's shoulders; at others, took men with their heels
upwards, and hurried them about with such indecency, as to expose
their nudities; and sometimes they tumbled round the sepulchre like
tumblers on a stage. In a word, nothing can be imagined more rude and
extravagant than what was acted upon this occasion.

"This frantic humour continued from twelve till four, and then the
Greeks first set out in a procession round the sepulchre, followed by
the Armenians, and marched three times round it with their standards,
streamers, crucifixes, and embroidered habits; and towards the end of
the procession, a pidgeon came fluttering into the cupola over the
sepulchre, at which the people redoubled their shouts and clamours,
when the Latins told the English gentlemen, that this bird was let
fly by the Greeks, to deceive the people with a belief that it was
a visible descent of the Holy Ghost. The procession being over,
the suffragan of the Greek patriarch, and the principal Armenian
bishop, approached the door of the sepulchre, cut the string with
which it was fastened, and breaking the seal, entered, shutting the
door after them, all the candles and lamps within having been before
extinguished in the presence of the Turks. As the accomplishment
of the miracle drew near, the exclamations were redoubled, and the
people pressed with such violence towards the door, that the Turks
could not keep them off with the severest blows. This pressing
forward was occasioned by the desire to light their candles at the
holy flame as soon as it was brought out of the sepulchre. The two
miracle-mongers had not been above a minute in the sepulchre, when
the glimmering of the holy fire was seen through some chinks in the
door, which made the mob as mad as any in bedlam; then presently came
out the priests, with blazing torches in their hands, which they
held up at the door of the sepulchre, while the people thronged with
extraordinary zeal to obtain a part of the first and purest flame,
though the Turks laid on with their clubs without mercy. Those who
got the fire immediately applied it to their beards, faces, and
bosoms, pretending that it would not burn like an earthly flame; but
none of them would endure the experiment long enough to make good
that pretension. However, so many tapers were presently lighted, that
the whole church seemed in a blaze, and this illumination concluded
the ceremony."

Maundrel afterwards observes, that the Latins take great pains to
expose this ceremony as a shameful imposition, and a scandal to the
Christian Religion: but the Greeks and Armenians, lay such stress
upon it, that they make the pilgrimages chiefly on this account; and
their priests have acted the cheat so long, that they are forced
now to stand to it, for fear of endangering the apostacy of the
people. They entertain many absurd ideas respecting the miraculous
power of the holy fire. Even the melted wax of the candle, which had
been lighted by it, is covered over with linen, and designed for
winding-sheets; "for they imagine," says Maundrel, "that if they are
buried in a shroud, smutted with this celestial fire, it will secure
them from the flames of hell!"

Before concluding this article, we shall mention a subject highly
interesting in optics, which, in some of its forms, was employed
by the old magicians; we mean the phantasmagoria. The exhibitions
of this kind, when first got up, drew the attention of Europeans,
and particularly the French, who greatly improved the apparatus and
machinery, and varied the forms and appearances. The principles of
the phantasmagoria are described in every work on Natural Philosophy,
which treats of optics. The _Dictionnaire de l'Industrie_,
_Encyclopedie Méthodique_, Biot's _Traité de Physique_, in French
and in English, the different treatises on philosophy and optics,
particularly Dr. Smith's, the Cyclopedias, &c. contain either a
description, or the principles of it. The third volume of Biot,
especially, is full on the subject of optics. With regard, however,
to the narrative and explanation of the appearance of the phantoms,
and other figures, a subject which immediately concerns us, the
account given by Mr. Nicholson, (_Journal of Natural Philosophy,
Chymistry, and the Arts_, vol. i, p. 147.) is the most interesting.
Connected with this optical illusion, is the imitation of lightning
and thunder, which, from the account, appears also to have been
performed.

The phantasmagoria may be considered nothing more than an application
of the magic lantern, the invention of which is attributed to Roger
Bacon, who was a contemporary with Vitellio, a native of Poland, who
published a treatise on optics, in 1270. John Babtista Porta, of
Naples, who discovered the camera obscura, having formed a society
of ingenious persons at Naples, which he called the Academy of
Secrets, wrote the _Magia Naturalis_, containing his account of this
instrument, and, it is said, the first hint of the magic lantern.
Kircher, it is known, received his first information of the magic
lantern from this book, and afterwards improved it.

Adams (_Lectures on Natural and Experimental Philosophy_, vol. ii,
p. 232. Appendix by the English editor) very justly observes, that
persons, unacquainted with the principles of optics, have been
surprised at the great illusion of their sight, by an artificial
construction of many optical instruments, exhibited by showmen and
others: such, for instance, as the optical and dioptrical paradox;
the endless gallery; the animated balls by simple reflection;
phantoms; causing the appearance of a flower from its ashes; the
optical perspective box, and the cylindrical mirror: to which we may
add, the enchanted bottle; the enchanted palace; the magic lantern;
the magician's mirror; the perspective mirror; the camera obscura;
distorting and oracular mirror; the diagonal opera glass, &c. &c.;
all which may be seen in Smith's _School of Arts_.

We may also remark, that optical exhibitions sometimes accompany
those of fire, when performed on a small scale. In the
phantasmagoria, for instance, whether before, or at the time the
exhibition commences, as well as after, thunder and lightning, if
well imitated, produces a good effect.

The mechanism of the phantasmagoria is concealed from the spectators,
who have only before their eyes a screen of gauze or gummed muslin
posited vertically, which serves as the ground of a picture,
where the images are depicted by reason of the transparency. The
apartment is deprived of all light, except that which proceeds
from an apparatus hid behind the screen. At the moment when the
operation commences, a spectre appears (as a skeleton, the head
of a celebrated person, &c.), at first extremely small, but which
afterwards increases rapidly, and thus seems to advance at a great
rate towards the spectators. And when the scene passes before them in
a room representing a cave hung with black, a solemn silence being
occasionally interrupted by mournful sounds from an appropriate
musical instrument, it is not easy for an observer to defend himself
from the impression of terror, at the sight of an object, in itself
formed to produce the illusion, and which finds in the imagination a
place already prepared for the reception of phantoms.

The instrument placed behind the gauze screen is in fact a peculiar
construction of the magic lantern: only in the former, it is
necessary that the lenses should run over a much greater space,
and that the instrument may be susceptible of approaching to,
and receding from, the frame of gauze, in such manner, that each
luminous pencil may be depicted there in a single point. The general
construction is this: In a square box, a lamp is placed, the luminous
rays proceeding from which, are reflected by a conical mirror,
towards an orifice made in the box. At this orifice is placed a tube,
blackened within, and composed of several tubes which slide one into
another, like those of a pocket telescope. This tube is furnished
with two bi-convex lenses of about five inches diameter; one of these
is fixed, the other is at the outer extremity of the tube, and is
separated from the former in proportion as the tube is lengthened by
the aid of a hooked lever situated along the tube, between the lamp
and the lenses. A groove is properly adapted to the tube, destined
to receive transparent figures; lastly, the box rests upon a table
moveable on four wheels, that slide in two channels perpendicularly
to the frame on which the images are depicted. It is manifest,
that we may augment or diminish the dimensions of the images,
and consequently make the spectre appear more or less near to the
spectator, by separating farther, or by bringing nearer together, the
two lenses; but then the focus of the diverging rays, which proceed
from the same point of the transparent body, will be no longer upon
the screen; we must, therefore, cause the machine so to recede or
approach, that the two motions, being duly combined, the image may be
distinctly formed.

These phantasmagoria are furnished with a great number of
transparencies, in each of which, several changes may be made by
slackening their springs. Thus we may change at every instant, the
form, the magnitude, and the distance of the spectres, as they appear
to the spectator.

What has been said hitherto, relates only to the images of
transparent figures. To obtain those of opaque bodies, first place
the gauze and box, at the distance of about six feet one from the
other, and adapt to the orifice of the box, an apparatus of two
tubes furnished with two bi-convex lenses. An opaque body, such, for
example, as a medal, or a picture, is attached to a little support,
posited in the middle of the box; the lamp with its supply of air,
situated in one of the foremost corners of the box, illuminates that
object, and the reflected rays, crossing the lenses, proceed till
they trace the image upon the gauze, with an amplification which is
in the ratio of the distances.

If the image be not distinct, we must infer that it is not at the
focus; but it may be adjusted in three different ways; 1. By moving
the box to or from the gauze; 2. By moving the object nearer to, or
farther from, the lenses within the box; 3. By slowly moving the
tubes, to cause a variation in the distance between the lenses.--See
Haüy's _Philosophy_, translated by Gregory, vol. ii, p. 390.

Mr. Nicholson, however, witnessed an exhibition of the phantasmagoria
at the London Lyceum by Philipstal, who took out a patent for his
improvements in the apparatus and machinery. He observes, that the
novelty consists in placing the lantern on the opposite side of the
screen which receives the images, instead of on the same side as the
spectator, and suffering no light to appear but what passes through,
and tends to form those images. His sliders are therefore perfectly
opaque, except that portion upon which the transparent figures are
drawn, and the exhibition is thus conducted.

All the lights of the small theatre of exhibition were removed,
except one hanging lamp, which could be drawn up, so that its flame
should be perfectly enveloped in a cylindrical chimney, or opaque
shade. In this gloomy and wavering light, the curtain was drawn up,
and presented to the spectator a cave or place exhibiting skeletons,
and other figures or terror, in relief, and painted on the sides
or walls. After a short interval, the lamp was drawn up, and the
audience were in total darkness, succeeded by thunder and lightning;
which last appearance was formed by the magic lantern upon a thin
cloth or screen, let down after the disappearance of the light, and
consequently unknown to most of the spectators. These appearances
were followed by figures of departed men, ghosts, skeletons,
transmutations, &c. produced on the screen by the magic lantern on
the other side, and moving their eyes, mouth, &c. by the well known
contrivance of two or more sliders. The transformations are effected
by moving the adjusting tube of the lantern out of focus, and
changing the slider during the moment of the confused appearance.

It must be again remarked, that these figures appear without any
surrounding circle of illumination, and that the spectators, having
no previous view or knowledge of the screen, nor any visible object
of comparison, are each left to imagine the distance according
to their respective fancy. After a very short time of exhibiting
the first figure, it was seen to contract gradually in all its
dimensions, until it became extremely small, and then vanished.
This effect, as may easily be imagined, is produced by bringing
the lantern nearer and nearer the screen, taking care at the same
time to preserve the distinctness, and at last closing the aperture
altogether: and the process being (except as to brightness) exactly
the same as happens when visible objects become more remote, the mind
is irresistibly led to consider the figures, as if they were receding
to an immense distance.

Several figures of celebrated men were thus exhibited with some
transformations; such as the head of Dr. Franklin being converted
into a skull, and these were succeeded by phantoms, skeletons, and
various terrific figures, which instead of seeming to recede and
then vanish, were (by enlargement) made suddenly to advance; to the
surprise and astonishment of the audience, and then disappear by
seeming to sink into the ground.

This part of the exhibition, which by the agitation of the spectators
appeared to be much the most impressive, had less effect with me than
the receding of the figures; doubtless because it was more easy for
me to imagine the screen to be withdrawn than brought forward. But
among the young people who were with me, the judgments were various.
Some thought they could have touched the figures, others had a
different notion of their distance, and a few apprehended that they
had not advanced beyond the first row of the audience.

The whole, as well as certain mechanical inventions, were managed
with dexterity and address. The lightning, being produced by the
camera, was tame, and had not the brisk transient appearance of the
lightning at the theatres, which is produced by rosin, or lycopodium
powder, thrown through a light, which in Mr. P's utter darkness might
easily have been concealed in a kind of dark lantern.

A plate of thin sheet iron, such as German stoves are made of, is an
excellent instrument for producing the noise of thunder. It may be
three or four feet long, and the usual width. When this plate is held
between the finger and thumb by one corner, and suffered to hang at
liberty, if the hand be then moved or shaken horizontally, so as to
agitate the corner at right angles to the surface, a great variety
of sounds will be produced; from the low rumbling swell of distant
thunder, to the succession of loud explosive bursts of thunder from
elevated clouds. This simple instrument is very manageable, so that
the operator soon feels his power of producing whatever character of
sound he may desire; and notwithstanding this description may seem
extravagant, whoever tries it for the first time will be surprised at
the resemblance. If the plate be too small, the sound will be short,
acute, and metallic.

We may remark also, that the magic lantern, by new contrived sliders
and machinery, may be applied to important uses, by employing it
with such figures as will explain the general principles of optics,
astronomy, botany, &c.

The experiment mentioned by Ferguson, with a concave mirror,
reflecting into the air the appearance of fire, &c. into a focal
point, (founded on a general principle of concave reflectors,) is
productive of many agreeable deceptions, and which exhibited with art
and an air of mystery, has been very successfully employed.

The phantasmascope of Walker is similar to the phantasmagoria. It
is an optical machine, which presents a door that opens itself. The
apparatus is so contrived, that, on opening the door, a phantom makes
its appearance, having all the colours of a picture, which approaches
the spectator. Various figures may be accurately represented.

We will not enlarge on this subject, although many other instances
of tricks, performed by means of fire, &c. might be noticed. We will
merely remark:

1. For the performance of these exhibitions, the ancient, as well
as the modern jugglers, of _all_ descriptions, employed, and were
acquainted with sundry mixtures, and compositions, by the use of
which, they deceived the people; and some pretended to possess
supernatural agencies. Of these compositions, with many of which we
are unacquainted, we have enumerated some, and their effects. That
of producing a callosity of the skin, &c. by means of acids, is an
example.

2. That they possessed, as a trade or profession, the arts of
deception. Not only by the use of chemical preparations, but by
other means, they pretended to work miracles in the dark ages of
science. However degraded these persons may seem, they yield in vice
to another class, who practised the art of poisoning, and who kept
it so profound a secret, that few then understood the effect of the
now common, vegetable, and mineral poisons. Who could have been more
infamous than the celebrated female poisoner, Tophania?

CHAPTER II.

OF THE SUBSTANCES USED IN THE FORMATION OF FIRE-WORKS.

_Sect. I. Of Nitrate of Potassa, or Saltpetre._

Nitrate of potassa, nitre, or saltpetre, is composed, as its name
expresses, of nitric acid, and potassa. When pure, it contains,
according to Kirwan, potassa 51.8, nitric acid 44, and water 4.2
in the hundred. This salt, when pure, or even mixed with other
saline substances, is recognised by placing it on hot coals. Slight
detonations, and a hissing noise, with a vivid combustion take place.
It is also decomposed by sulphuric acid, and the nitrous vapour is
apparent from its smell and colour.

Nitrate of potassa crystallises in six-sided prisms, terminated by
six-sided pyramids. Its specific gravity is 1.933. Its taste is sharp
and cooling. One part is soluble in seven parts of water, at the
temperature of 60 degrees, and in rather less than its own weight of
boiling water.

It melts in a strong heat, and by cooling congeals into an opaque
mass, called _crystal mineral_, or _sal prunelle_.

Exposed to a red heat, it disengages _oxygen gas_, and passes to the
state of a nitrate; at a higher temperature, this is decomposed, and
oxygen, azote, and a portion of nitrous acid, which has not been
decomposed, are evolved. What remains is potassa. When projected on
ignited coals, it burns brilliantly. Detonation also ensues by mixing
nitre and charcoal, and throwing the mixture into a red-hot crucible.
The residuum is carbonate of potassa. Fourcroy (_Système des
Connoissances Chimiques_, Tome iii, p. 124.) observes, that metals,
with nitrate of potassa, will decompose this salt, and produce
different coloured flame, extremely brilliant, on which account such
substances are used in fire-works.

The alchymists believed, they could obtain, from nitre, a liquor,
which would constitute, with other substances, the _philosopher's
stone_. The _clyssus_ of nitre, they imagined, possessed wonderful
properties. The decomposition of nitre by charcoal, they effected
in two ways, _viz._ by submitting the mixture to the action of heat
in a crucible, or, otherwise in an earthen or iron retort. In the
latter case, they collected a fluid, principally water, containing
some carbonic acid, and the aeriform product they suffered to
escape. The residue they named _nitre fixed by charcoal_, or, _the
extemporaneous alkali of nitre_. When, in the place of charcoal, a
mixture of sulphur and nitre was projected into a red-hot crucible,
they obtained a saline substance, to which they gave the name of _sal
polychrest_. This is the same as vitriolated tartar, or sulphate of
potassa, and is that salt which is formed in the distillation of
nitric acid from nitre, and sulphuric acid. The _crystal mineral_,
of some of the old pharmacopœias, was nothing more than nitrate of
potassa fused with a portion of sulphur, and, therefore, a mixed
salt, consisting of nitrate and sulphate of potassa.

Nitrate of potassa, distilled with half its weight of sulphuric acid,
furnishes nitric acid, or concentrated spirit of nitre. This, diluted
with about an equal weight of water, forms the _aqua fortis_ of the
shops.

A mixture of nitre and phosphorus, if struck with a hammer, produces
a violent detonation. Nitre oxidizes all the metals at a red heat,
even gold and platinum.

Nitre and sulphur, thrown into a red-hot crucible, produces an
instantaneous combustion, accompanied with a great disengagement of
light and heat. Sulphurous acid gas, with sulphuric acid, is produced.

Equal parts of cream of tartar, (supertartrate of potassa,) and
nitre, deflagrated in a crucible, form _white flux_. Two parts of
tartar, and one of nitre, treated in the same manner, produce _black
flux_.

Three parts of nitre, one part of sulphur, and one part of sawdust,
mixed together, form the _powder of fusion_.

When three parts of nitre, two parts of potash, and one of sulphur,
all previously well dried, are mixed together, the compound is called
_pulvis fulminans_, or, _fulminating powder_. A small portion of this
powder, or as much as will lay on a shilling-piece, put on a shovel,
and exposed to heat, will first melt, become liver-coloured, and
then explode with great noise. The theory of this explosion is, that
a part of the sulphur, and the potassa unite, and form a sulphuret;
the sulphuret then decomposes water, and produces sulphuretted
hydrogen gas, which appears to be decomposed by the nitric acid; and
there results sulphurous acid gas, water, and, as Thenard observes,
protoxide of azote, azotic gas, and sulphate of potassa. The loudness
of the report depends on the combustion of the whole powder at the
same instant, which is secured by the previous fusion it undergoes.
Gunpowder, on the contrary, burns in succession, although apparently
instantaneous. In using common potash, there is also, as the alkali
contains it, carbonic acid, given out in the state of gas. In fact
carbonic acid appears to assist the explosive effect of this powder,
for when it is prepared with potash, containing little carbonic acid,
its detonating power is considerably less.

Nitre likewise enters into the composition of another fulminating
powder, invented by Dr. Higgins. _Higgins's fulminating powder_ is
composed of three and a half parts of nitre, two parts of crude
antimony, and one part of sulphur. This is used in the same manner as
the former.

Nitre enters into the composition of gunpowder, which we shall
notice under a separate head. The proportions of nitre, sulphur,
and charcoal, for the formation of gunpowder, which are considered
the best, are, 75 parts of nitre, 12-1/2 of charcoal, and 12-1/2 of
sulphur.

The new powder of MM. Gengembrie and Bottée, which inflames by
percussion, but without explosion, is composed of 21 parts of nitre,
54 parts of chlorate of potassa, 18 parts of sulphur, and 7 parts of
lycopodium.

A mixture of nitre and crude antimony projected into a red-hot
crucible, produces a deflagration more or less rapid, forming a
composition which is used in pharmacy, and medicine.

The quality of saltpetre may be determined by a variety of
experiments. Fire-workers judge of its quality by the colour of its
flame.

The flame should be white. If it be _green_ or _yellow_, it is said
to be impure.

Nitric acid, obtained by distilling saltpetre and sulphuric acid,
has a powerful effect on inflammable substances. If nitric acid,
or in preference, the fuming nitrous acid, be poured on spirit of
turpentine, especially if it be old, it will inflame. To succeed,
however, in this experiment, a small portion of sulphuric acid is
usually added to the nitric acid. As this effect is owing to the
facility, with which the acid parts with its oxygen to inflammable
bodies, other essential oils, besides turpentine, will have the same
effect. If the same acid is poured on finely pulverized charcoal, or
on lampblack, combustion will also take place. When oils are used,
water as well as carbonic acid is produced, and when charcoal or
lampblack, carbonic acid alone. There is also a large quantity of
carbon, in the former instance, which remains on the plate, or dish.
M. Delametherie (_Journal de Physique_, 1815) has shown, that olive
oil may be converted into a substance, resembling, and having many
of the properties of, wax, by mixing it with a given proportion of
nitric acid. The acid is decomposed, deutoxide of azote is formed,
and the oil acquires a hard consistence. A candle made with this
artificial wax, he observes, burns with a clear light and without
smoke. The experiment with the _glace inflammable_ is on the same
principle.

Morey (_Silliman's Journal_, vol. ii, p. 121.) states a singular
experiment, in which nitre is used; _viz_: If to tallow or linseed
oil, a small quantity of saltpetre be added, and the temperature
raised to nearly that of the boiling point, the saltpetre appears
to be dissolved by the oil; they will _evaporate together_, and
the mixture, or the vapour, will burn, _wholly excluded from the
atmosphere_.

Saltpetre was one of the substances employed by the alchemists. It
appears from the memoir of Geoffroy, (_Coll. Academ._ 1722,) that the
object of the alchemists was twofold; the transmutation of metals,
and particularly what were denominated the _baser_ metals into the
precious, which they pretended to effect by a _universal spirit_, the
_grand elixir_, the _philosopher's stone_, &c. and the reduction of
metals to their _earths_. Alchemy was introduced into Europe by the
crusaders, and it is remarkable, that, in the reign of Henry IV,
an act was passed to make it felony to transmute metals. Mr. Boyle,
aware of its absurdity, suggested the propriety of repealing that
act, which was done. One of their powders was composed of nitre,
cream of tartar, and sulphur.

_Preparation._ Although nitrate of potassa is generated in
abundance, particularly in the East, yet in all countries, where
the circumstances are favourable to its production, it is found. It
never occurs, native, in very large masses. It is generally found
in an efflorescence, on the surface of the soil, or in caverns. It
never exists in the soil more than a few yards beneath the surface.
We may remark, that native nitre has never been found in pure clay,
or pure sand, except in the _rock-ore_, as it is called, of the
western United States. It is often found in caverns, and fissures in
calcareous rocks.

In the East Indies, the districts which furnish saltpetre, are swept
at certain seasons of the year. This is repeated two or three times a
week; for the saltpetre again appears in the same places, in the form
of efflorescence.

It is supposed that some countries furnish saltpetre, in consequence
of the drought, which continues for some time. At Lima, M. Dombay
informs us, there is seldom rain; and the fields, which serve as
pasturage for beasts, are so much covered with saltpetre, as to be
removed with the spade. There must then be a rapid formation of
nitre. M. Talbot observes, that in the meridional provinces of Spain,
the earth frequented by animals, contains it, ready formed. When
saltpetre became an article of importance, the rulers of Germany, &c.
justified themselves in exclusively carrying away the incrustations
of walls from private houses, which, when it could be used, became
_accessorium fundi_. Accordingly this _regale_, as it was called, was
extended every where, and was generally unpopular. In 1419, Gunther,
archbishop of Magdeburgh, issued the first grant, which was the right
of searching saltpetre and boiling it, during a year, in the district
of Gibicherstein, for which the person, to whom it was granted, was
to pay a barrel of saltpetre, and deliver to the archbishop the
remainder at a certain price.

The succeeding archbishop, Frederick, let, in 1460, to a burgher of
Halle, all the earth and saltpetre that could be collected in the
bailiwick of Gibicherstein, for four years, at the annual rent of a
given quantity of refined saltpetre. Bishop Ernest, in 1477, let, for
his time, the privilege of collecting saltpetre. In 1544, saltpetre
was collected, in the same manner, from the rubbish before the
gates of Halle; and in the year following, the magistrates of Halle
erected a powder mill, and had saltpetre works. John VI, archbishop
of Triers, granted similar privileges in 1560. The saltpetre regale,
was long known, and confirmed by a Brandenburgh decree in 1583.

Old walls, and the vicinity of stables, frequently exhibit saltpetre
in the state of efflorescence. It was the ancient _scrophula contra
lapides_, represented as a kind of leprosy. For the spontaneous
production of nitre, animal and vegetable substances, in a state of
decomposition, and the presence of dry atmospheric air are necessary.
That lime, and the calcareous carbonates also promote its formation,
there can be no doubt.

Notwithstanding the large quantity of saltpetre collected in the East
Indies, we are told, that two-thirds of the whole are annually sent
into China, and other parts of Asia, to make artificial fire-works.
The pyrotechny of the Chinese is said to be very perfect; in variety
and beauty, some writers assert they exceed all other nations. There
is a natural nitre bed at Apulia, near Naples, which affords 40
per centum of nitre. Pelletier, (_Ann. de Chim._ tome xxii.) has
published an analysis. The cavity of Molfetta is one hundred feet
deep, containing grottos or caverns. Nitrate of potassa is found
in the interior, in efflorescence or crusts, attached to compact
limestone. On removing these efflorescences, others appear. The soil
in this cavity is richly impregnated with nitre.

In Switzerland, the farmers extract an abundance of saltpetre from
the stalls under their cattle. During the American revolution, when
every expedient was resorted to, to obtain a supply of this article,
the floors of tobacco houses, &c. were dug up and lixiviated. In the
reign of Charles the First, certain patentees were authorised to dig
up the floors of all dove-houses, stables, &c. the floors being again
laid with mellow earth.

The Ukraine, Podolia, Hungary, Spain, Italy, Peru, and India, furnish
more or less of this salt, which is extracted by lixiviating the
earths that compose the soil. The springs, in particular districts of
Hungary, contain it.

We are informed, (_Ann. de Chim._ xx. 298,) that, during the second
and third years of the French Republic, the government required
every district to send two intelligent young persons to Paris. This
convocation, consisting of nearly eleven hundred persons, received
regular instruction from their first chemists, partly concerning
the manufacture of cannon, and partly respecting the manufacture
of saltpetre and gunpowder. This body of pupils was afterwards
distributed among the different establishments in proportion to their
abilities, and saltpetre was soon furnished in abundance.

In the United States, we have an abundant source of saltpetre in
the _nitre caves_ of the western country. There is now no occasion
for lixiviating the soil of tobacco houses, or of stables, or the
refuse of old buildings, the preparation of artificial nitre beds, as
adopted in France, or for any other expedient, to furnish a supply
of saltpetre; these caverns, which are calcareous, producing it
in great abundance. The _earth_ of these caves does not, however,
contain pure nitrate of potassa, but generally a mixture of this
salt and nitrate of lime, a calcareous nitrate which constitutes the
principal part. The latter is changed into nitrate of potassa, as we
shall observe more particularly hereafter, by making a lixivium of
the earth in the usual manner, and passing it through wood ashes. The
alkali, which the latter contains, decomposes the nitrate of lime, by
uniting with the nitric acid; hence the fluid, which passes through,
is nitrate of potassa or saltpetre. This is evaporated, and suffered
to crystallize. It is then the _crude, or rough nitre_, which is
purified, principally by re-solution, and crystallization.

The saltpetre makers, at the caves, have found, that two bushels
of ashes, made by burning the dry wood in hollow trees, afford as
much alkali as eighteen bushels of ashes obtained from the oak.
Notwithstanding the _nitre earth_ contains a mixture of the nitrates
of potassa and lime, nitrate of potassa, nearly pure, has been
discovered. It is sometimes found in the fissures of sandstone, or
among detached fragments. Some of these masses are said to weigh
several hundred pounds.

Besides these caverns, which have been accurately described by Dr.
Brown, in the Transactions of the _American Philosophical Society_,
(vol. v, vi.) similar caverns have been discovered in Tennessee,
and in some parts of Virginia and Maryland. At Hughes' cave near
Hagerstown, in Maryland, this salt has also been made.

We are of opinion, that most of the calcareous caverns in the United
States, if carefully examined, might be found to contain nitre, or at
least, the calcareous nitrate, which is readily converted into nitre
by lixiviation with wood ashes, or the addition of a due quantity of
potash.

Professor Cleaveland, in noticing the saltpetre caves of the
western country, observes, (_Elementary Treatise on Mineralogy and
Geology_,) that one of the most remarkable of these caverns is
in Madison county, on Crooked Creek, about sixty miles S. E. from
Lexington. This cavern extends entirely through a hill, and affords a
convenient passage for horses and wagons. Its length is six hundred
and forty-six yards; its breadth is generally about forty feet; and
its average height, about ten feet. One bushel of the earth of this
cavern, commonly yields from one to two pounds of nitre; and the same
salt has been found to exist, at the depth of at least fifteen feet;
even the clay, a fact which seems rather remarkable, is impregnated
with nitrate of lime. Kentucky also furnishes native nitre under a
very different form, and constituting what is there called the _rock
ore_, which is in fact a sand stone, richly impregnated with nitrate
of potassa. These sand stones are generally situated at the head of
narrow vallies, which traverse the sides of steep hills. They rest on
calcareous strata, and sometimes present a front from sixty to one
hundred feet high. When broken into small fragments, and thrown into
boiling water, the stone soon falls into sand; one bushel of which,
by lixiviation and crystallization, frequently yields ten pounds, and
sometimes more than twenty pounds of nitrate of potassa. The nitre
from these rocks contains little or no nitrate of lime. This account
is corroborated by Dr. Brown,[13] to whom our author is indebted for
his remarks.

In a memoir in the American Philosophical Transactions by Dr. Brown,
then of Lexington Kentucky, we have a description of a nitre cave
on Crooked Creek, with the process for extracting the saltpetre.
From this memoir, the following extracts are made: The water which
percolates through the cave in summer, as the walls and floor are dry
in winter, condenses upon the rocks, and the substance thus formed,
has the same properties as the salt obtained by lixiviating the earth
of the floor. As far as the workmen have dug, the earth is strongly
impregnated, every bushel of which, upon an average, furnishes one
pound of nitre. The same earth will be again impregnated, if thrown
into the cave. What length of time it requires to saturate it, is not
known.

The workmen have different modes of forming an opinion with regard
to the quantity of nitre, with which the earth may be impregnated.
They generally trust to their taste; but it is always considered as
a proof of the presence of the nitre, when the impression made one
day on the dust by the hand or foot disappears the day following.
Where there is a great deal of sand mixed with the dust, it is
commonly believed that a small quantity of potash will suffice for
the operation. The method of making saltpetre, usually practised in
Kentucky, is as follows:

The earth is dug, and carried to hoppers of a very simple
construction, which contain about fifty bushels. Cold water is poured
on it for some time, and in a day or two, a solution of the salts
runs into troughs placed beneath the hoppers. The lixiviation is
continued as long as any strength remains in the earth. The liquor
is then put into iron kettles, and heated to ebullition; it is
afterwards thrown upon a hopper containing wood ashes, through which
it is suffered to filtrate. As the alkaline part of the ashes is
discharged before the nitrate passes through, the first runnings of
this hopper are thrown back, and after some time, the clear solution
of nitrate of potassa runs out, mixed with a white curd, which
settles at the bottom of the trough. This clear liquor is boiled to
the point of crystallization, then settled for a short time, and put
into troughs to crystallize, where it remains twenty-four hours;
the crystals are then taken out, and the mother water thrown upon
the ash hopper, with the next running of the nitrate of lime. When
the quantity of the nitrate of lime is too great for the portion of
ashes employed, the workmen say their saltpetre is in the _grease_,
and that they do not obtain a due quantity of nitre. If too much
ashes are used, they say it is in the _ley_; and when it is left to
settle previous to crystallization, a large quantity of salt will be
deposited in the settling troughs, which they call _cubic salts_.
These salts are again thrown upon the ash-hoppers, and are supposed
to assist in precipitating the lime from the nitrate of lime, and
in the opinion of the workmen are changed into pure saltpetre. To
make a hundred pounds of good saltpetre at the great cave, eighteen
bushels of oak ashes are necessary; ten of elm, or two of ashes made
by burning the dry wood in hollow trees. The earth in some caves does
not require half this quantity of wood ashes to decompose the earthy
salts.

When wood ashes cannot be obtained in sufficient quantity, they make
a lixivium of the earth, and boil it down, which they call _thick
stuff_. This is put in casks, and transported to a place where ashes
can be had. When dissolved and passed through wood ashes, it is
changed, as in the former process, into saltpetre. Having thus given
the Doctor's account, let us inquire, in the next place, into the
theory of the process.

The theory is very evident. The mixed nitrate, consisting of variable
proportions of nitrate of lime and nitrate of potassa, is extracted
from the saltpetre earth by water, which dissolves it. Now, as
the affinity of nitric acid for potassa is greater than for lime,
and consequently potassa will decompose nitrate of lime, when the
lixivium is passed through wood ashes, the potassa they contain
will unite with the nitric acid, and the lime be separated, which
remains in the hopper. The liquor holds in solution no other salt
than nitrate of potassa, provided the quantity of alkali in the wood
ashes be sufficient to effect the decomposition;--if _more_, it will
pass through in an uncombined state; and if _less_, the liquor will
contain nitrate of lime. As the alkali contains more or less carbonic
acid, the decomposition is not a case of single but of double
affinity, in which we form, at the same time, a carbonate of lime.

When the solution is boiled, and set aside in the troughs to
crystallize, the nitre will form in a regular manner. The mother
water, or the fluid which remains after the crystallization, may
contain, from the circumstance before stated, either potash, or
undecomposed nitrate of lime--hence it is thrown on the hopper in a
subsequent operation.

The nitre, however, as made at the caves, is called _rough_ or crude
nitre. Before it is used for the manufacture of gunpowder, and other
purposes, it is purified or refined. This operation, which we shall
notice more fully hereafter, is nothing more than the separation of
all earthy salts, and the alkaline muriates and sulphates; in other
words, the conversion of the whole by the separation of foreign
substances, into pure nitrate of potassa.

The mode of treating the _rock ore_, or sand rocks, which contain
nitre, is the same as before given. It contains more nitrate of
potassa, and therefore requires less potash, and in some instances,
the nitre is perfectly pure. The sand rocks often yield twenty or
thirty pounds per bushel. A mass of pure nitre, weighing sixteen
hundred pounds, has been discovered. Smaller masses have also been
found.

The rocks which contain the greatest quantity of nitre are extremely
difficult to bore, and are tinged brown or yellow.

Saltpetre makers find it to their interest to work the rock ore in
preference to the calcareous nitrate, as it yields more nitre.

It is a fact well known, that foreign saltpetre contains a variety of
deliquescent salts, or those salts which attract and absorb moisture
and also common salt. The efforts of European refiners are directed
to their separation. The saltpetre of the Western country, Dr. Brown
assures us, does not contain common salt.

Dr. Brown, in _Silliman's Journal_, i, p. 147, in a letter to
professor Silliman, observes, that there exists a black substance in
the clay under the rocks, of a bituminous appearance and smell. This
black substance, it appears, accompanies the sand-rock nitre, and is
the same as that found in Africa, which also accompanies nitre in
that country. Animal matter seems to have existed in the nitre caves
of Africa, forming, as Mr. Barrow expresses it, either a _roof_ or
covering; no such matter, however, has ever been found in or adjacent
to the nitre caves of the Western country.

The observations of Mr. Barrow on the subject of the saltpetre of
Africa may be interesting to the reader. He observes, (_Southern
Africa_, p. 291,) that, about twelve miles to the eastward of the
wells, (_Hepatic Wells_), in a kloof of the mountain, we found a
considerable quantity of native nitre. It was in a cavern similar
to those used by the Bosgesmans for their winter habitations. The
_under surface_ of the projecting stratum of calcareous stone, and
the sides that supported it, were incrusted with a coating of _clear,
white saltpetre_, that came off in flakes. The fracture resembled
that of refined sugar; it burnt completely without leaving any
residuum; and if dissolved in water, and thus evaporated, crystals
of pure _prismatic nitre_ were obtained. This salt, in the same
state, is to be met with under the sand-stone strata of many of
the mountains of Africa. There was also in the same cave, running
down the sides of the rock, a black substance, that was apparently
bituminous. The peasants called it the urine of the das. The dung of
this _gregarious_ animal was lying upon the roof of the cavern to the
amount of many wagon loads.

The Rev. Mr. Cornelius, in describing a cave in the Cherokee country
at Nicojack, the north west angle in the map of Georgia, (_Silliman's
Journal_, vol. i, p. 321,) observes, that it abounds with nitrate
of potassa, a circumstance very common to the caves of the Western
country, and is found covering the surfaces of fallen rocks, but
in more abundance beneath them. There are two kinds; one is called
the "clay dirt," the other the "black dirt." The earth, however,
contains calcareous nitre, and for that reason an alkaline lixivium
is employed. In short, the process employed there is the same as at
the other saltpetre caves which we have described. One bushel of the
clay dirt yields from three to five pounds of nitre, and the black
dirt from seven to ten pounds. It seems also, that the same dirt, if
carried back to the cave, will become impregnated with nitre.

Mr. Cornelius remarks, that these caves have been used by the
natives as burial places; in one of which he counted a hundred human
skulls in the space of twenty feet square; and infers, that, by the
decomposition of animal matter, the acid of nitric salts arises, and
therefore that this may have occasioned the formation of the nitrates
of potassa and lime.

At Corydon, in Indiana, there is a cave, which, according to
Stilson's account, contains both nitrate of lime, and nitrate of
magnesia. It is not worked.

Kain, in his remarks on the Geology and Mineralogy of East Tennessee,
(_Silliman's Journal_, vol. i, p. 65,) observes, that the numerous
caves which have been found in the Cumberland mountains, and
other parts of Tennessee have been very productive of nitrate of
potassa; and in confirmation of the remarks before made, he adds, in
investigating the causes that have given rise to these salts, that
wild animals burrow in these caves; that, when pursued by the hunter,
they make them the places of their retreat, and probably die there;
that the aborigines have made them a place of burial; and that the
streams of water, which flow through them, in wet weather, carry with
them not only great quantities of leaves, but many other vegetable
productions.

Without offering any theory, by which we may account for the
formation of nitre, in nitre caves, or in situations which cannot
be influenced by the putrefactive process, we may merely remark,
that as nitric acid is composed of oxygen and azote, there must be
some operation unknown to us, by which the union of these elements
takes place. Nascent azote must unite with the base of oxygen gas;
but whence, in saltpetre caves, proceeds the azote and the oxygen?
It appears that calcareous bodies facilitate the formation of nitre,
as they do in artificial nitre beds. The greater part of the nitrous
earth is lime; and it also appears, that the same earth, after the
extraction of the saltpetre, will again furnish it. We know that lime
is a compound of a base called calcium united with oxygen; but in
what manner it promotes the union of azote and oxygen, or furnishes
either one or the other of these bodies, or perhaps both, is
altogether uncertain. Nor can we account for the formation of potash
in the native nitre of the nitre caves. In other situations, as for
instance where nitrous efflorescence appears on the earth, and in
artificial nitre beds, in which animal and vegetable substances are
in the act of decomposition by the putrefactive fermentation, we may
account for the generation of nitric acid.

It is extremely probable, that the azote of the atmosphere, and
oxygen may combine spontaneously, under particular circumstances, in
various operations of nature. Azote, it is known, forms with oxygen
two gases, a protoxide and deutoxide, and the same elements in other
proportions form nitric acid. Some condition, unknown to us, must,
as an operating cause, produce this compound. As a condition for its
generation, the presence of calcareous and alkaline matter, favours
the formation of nitric acid. Of this fact, we have sufficient
proof, in the generation of nitre in artificial nitre beds. But,
with respect to natural causes, although the facts themselves are
conclusive, we know little or nothing.

Atmospheric air is a mixture, or compound, according to some, of
two gases, oxygen and azote, with carbonic acid; but the proportion
of the latter rarely exceeds two per cent, while the quantity of
oxygen is about twenty-two. It is a solvent, as well as a vehicle,
and hence may contain water, gaseous fluids, &c. Miasmata, which is
contained often in the air, are vapours or effluvia, that affect the
human system, and bring on diseases, of which the principal are the
intermittent, remittent, and yellow fevers, dysentery and typhus.
That of the last is generated in the human body itself. The same, or
analogous causes, that produce the formation of nitric acid, may,
under other circumstances, cause the formation of miasmata; for moist
vegetable and other matter, in some unknown state of decomposition,
generates it, and is known to have caused the yellow and other
malignant fevers. (See an admirable work on the _causes, &c. of the
yellow fever in Philadelphia_, by SAMUEL JACKSON, M. D. president
of the board of health, etc. in reply to the observations of Dr.
Hosack.) The contagious _virus_ of the plague, small pox, etc. as it
operates in a more limited distance than marsh, or other miasmata, is
communicated only in certain localities, and through the intermedium
of the atmosphere. As to the chemical nature of miasmata, there can
be no doubt that azote, under some form of combination, is one of its
component parts, and one of the causes of disease. Is not cyanogen,
or carburet of azote, perhaps combined with hydrogen, in the form of
hydrocyanic or prussic acid, the substance, or _principal_ substance,
which forms the miasmata, that engenders the yellow fever? What
compounds may be formed of hydrogen, sulphur, phosphorus, carbon, and
_azote_, so as to produce miasmata, that will act specifically on the
system for the production of intermittent, remittent, yellow, typhus,
and other fevers?[14] This inquiry, permit me to add, is one of no
small moment, as it involves in it a question of great importance
relative to the origin of yellow fever. While we thus digress,
in noticing the compounds of azote, let us briefly remark, as an
indisputable conclusion, that the same causes of malignant disease
in the West India islands, operating under similar circumstances in
every respect, may engender the same disease in our cities.

The atmosphere is subject to changes of various kinds, and may be
considered not only as a solvent, but a repository for different
foreign bodies. Electricity, an agent so essential in the economy
of nature, has its ends, its uses; and while, no doubt, it unites
hydrogen with oxygen, in the most elevated regions of the air, and
forms water, it may act under particular circumstances to produce
a union of azote and oxygen so as to generate nitric acid. Dr.
Priestley, (_Transactions of the American Philosophical Society_,)
detected nitric acid in snow. But of all atmospheric phenomena, the
formation of meteorolites, or meteoric stones, is the most wonderful.
If they be really formed in the atmosphere, there can be no doubt,
that the elementary principles which compose them must exist in
it; and that the phenomenon denominated meteoric, in such cases,
is no other than the operating cause, by which meteoric stones are
generated.[15]

Animal substances furnish azote, as it is one of their constituent
parts; and in the act of its separation, by uniting with oxygen,
principally furnished by the air, it forms nitric acid; which,
attaching itself to the alkali of the vegetable matter, or the lime
usually added to nitre beds, or to other salifiable bases, forms
either nitrate of potassa, nitrate of lime, or a nitrate of the
particular base. The lixiviation of the nitrous substances, and the
use of wood ashes, or potash itself, will produce saltpetre.[16]

Brongniart has given the following process for purifying or refining
saltpetre: Pulverize the impure nitre, and wash it three times in
cold water, in the proportion of 35 lbs. of water, to 100 lbs. of
the salt, taking care to pour off the water before another portion
is added. These washings separate the greater part of the muriate
of soda, and the deliquescent salts, such as nitrate of lime. When
thus washed, the nitre is to be dissolved in half its weight boiling
water. On cooling, the salt begins to crystallize, and, by agitating
the liquid during the process, minute crystals are obtained. These
crystals when dried are to be washed in 5 lbs. of cold water for
every 100 lbs. of the salt, and then dried in a temperature of
forty-five degrees.

In India, where nitrate of lime also occurs, but in situations
different from those in the United States, the natives extract the
saltpetre by a process similar to that we have described. They refine
it by solution in water, evaporation, and crystallization. In
France, the potash of commerce is used; and the nitrates which are
decomposed, are those principally of lime and magnesia.

According to the analysis of M. Pelletier, and the experiments of
professor Vaizo, in 1781, they found the calcareous earth of the cave
at Naples, to contain forty or forty-two to the hundred, of nitrate
of potassa. (See _Annales de Chimie_, tome 23.)

In 1792, M. Pickel announced the discovery of native saltpetre, in
a quarry in the neighbourhood of Wurtzburgh. M. de la Rochefoucald
discovered nitre in the neighbourhood of chalk in France, in the
departments of Seine and Oise. MM. Lavoisier and Clouet, made a
number of researches with the same view. Since that time, saltpetre,
or nitrous earth has been found in several of the departments of
France; and it appears reasonable to conclude, that in all situations
favourable to the generation of nitre, where the same causes operate,
nitre must occur in more or less abundance.

From the rubbish of old buildings, saltpetre is obtained in some
quantity. Old plaster is said to give five per cent. The soluble
salts it contains, are six in number, viz: nitrate and muriate of
lime, nitrate and muriate of magnesia, and nitrate of potassa, and
muriate of soda. Now it is obvious, that besides the decomposition
of the earthy nitrates, the earthy muriates also are decomposed by
the potash, leaving in solution, besides muriate of soda, if it is
not decomposed, by the potash, (which has this effect,) muriate, as
well as the nitrate of potassa. To refine the saltpetre prepared in
this manner, consists in separating the muriates. The proportions, in
which these salts are to each other in a hundred parts, are stated
by Thenard, (_Traité de Chimie_, Tome ii, p. 485,) to be ten,
nitrate of potassa, seventy, nitrates of lime and magnesia, fifteen,
marine salt, and five, muriates of lime and magnesia.

The mode of extracting saltpetre, and the various processes which
have been adopted for refining it, in France, and on the continent
generally, have but one object,--that of lixiviating the substances
which afford it, and subsequently, separating all foreign salts. The
best memoir was written by count Chaptal, occupying forty-seven pages
in the _Annales de Chimie_, tome xx. In this he explains the theory
at large. In the same work, tome xxiii, there is also a paper by
Guyton, and many other memoirs of the same character. In Chaptal's
_Chimie Appliqué aux Arts_, tome iv, p. 119, in Thenard's _Traité
de Chimie_, tome ii, p. 485, and in the _Annales de Chimie et de
Physique_, tome v, p. 173, the subject is ably treated.

We will now give the process of extracting saltpetre from the rubbish
of old buildings, principally plaster, as adopted in France. The
lixiviation, in the first place, is performed in the following
manner: a certain number of casks or tubs, thirty-six for instance,
is placed in three ranges. These tubs are pierced laterally near
their bottom, by a hole of about half an inch in diameter, and
closed with a cork; they are placed above a trough connected with
a reservoir. There is put then into each tub a bucket full of the
plaster, previously pounded, which is supported in the casks by cross
sticks, a certain distance from the hole, so as not to obstruct the
passage of the fluid. After this, a bushel of wood ashes is added,
and the tubs are then filled with the plaster. Water is then put
into the tubs of the first row, and after some time, the stop cocks
are turned; water is then put into the tubs of another row, and
the lixiviation is continued until the fluid indicates the zero of
Beaumé's areometer. The saline waters, which are thus obtained, are
divided into three parts, in proportion to their specific gravity, or
quantity of salt they contain. The lixivium, of five degrees of the
areometer, is known under the name of _eaux de cuite_. The waters,
which are marked between three and five degrees, take the name of
_eaux de forte_; and those below three degrees are called _eaux
faibles_. According as the waters are weak, they are made to run
through another range of tubs, in order to saturate them.

When strong and weak solutions are made to pass through the tubs in
the same manner, proceeding from the second row to the third, and
from the third to the first, the _earths plaster_, &c. being renewed,
the lixiviation is not interrupted.

The lixiviation, it appears, is thus continued; for we obtain, at the
same time, _weak waters_ from the second row, the _strong waters_
from the third, and the _boiling waters_, or those fit to be put into
the boilers, from the first.

When a sufficient quantity of the strong solution is obtained,
it is put into the copper, or boiler, and evaporated. During the
evaporation, there is a scum formed, and sundry earthy substances,
in the form of a mud, are deposited. This is usually caught in a
vessel placed in the boiler, which is raised from time to time, by
means of a rope, moved through a pulley, and fastened to a chain from
the handles of the vessel. The solution is concentrated until it
indicates the strength of twenty-five degrees of Beaumé's areometer.
It is then mixed with the mother water of the preceding boiling, and
a concentrated solution of the potash of commerce is added, until
the precipitation ceases. The sulphate of potassa may be used for
the same purpose, at least to decompose the nitrate of lime; but it
must be used in the first instance, and the operation finished in
the common way, by the addition of potash. The precipitation being
finished, that is to say, the nitrates of lime and magnesia, being
transformed into nitrate of potassa, the hot liquor is then carried
in a large tub, called the _reservoir_, and placed on the edge of the
boiler. As soon as the insoluble salts, which the solution contains,
are deposited there, which takes place immediately, the liquor is
drawn off clear by cocks, which are adapted to the tubs, and received
into the boiler, previously cleaned. The deposite obtained in the
boiling, is washed with a certain quantity of the solution, which
becomes clear, and is then mixed with the preceding liquor.

From what has been said, the liquor must contain a great quantity
of nitrate of potassa, a small quantity of the salts of lime and
magnesia, and all the marine salt contained in the plaster. It is
frequently the case, that the liquor contains muriate of potassa, and
a small quantity of sulphate of lime. It is, therefore, submitted
again to evaporation. When it is at the forty-second degree of
concentration, some part of the marine salt separates, which rises to
the surface, and is taken off, and drained through an osier basket
placed over the boiler. The solution being concentrated to the
forty-fifth degree of the hydrometer, it is put into copper vessels,
in which, by cooling, it crystallizes. The salt is then separated
from the mother water, drained and coarsely bruised, and afterwards
washed in a certain quantity of the _first boiling_. It is now in a
state to be delivered to the central administration, under the name
of crude saltpetre, or saltpetre of the first boiling.

The crude saltpetre contains about seventy-five per cent of nitrate
of potassa. The quality may be determined by treating it with a
saturated solution of pure nitrate of potassa, which cannot dissolve
any more of the nitrate, but will dissolve any foreign salts. The
twenty-five parts of the foreign substances, contained in the crude
saltpetre, are composed of a large quantity of marine salt, and of
a small portion of muriate of potassa. It is necessary to separate
them, and other foreign substances. The operation for this purpose,
is called the _refining of saltpetre_.

The refining of saltpetre is founded principally upon the property,
which nitre has, of being more soluble in warm water, than the
muriate of soda, and muriate of potassa. Thirty parts of saltpetre,
and six parts of water are put into a boiler and the liquor is
heated. By this means, there is precipitated a large quantity of
marine salt mixed with muriate of potassa. A small quantity of water
is added from time to time, to keep the nitre in solution.

When the foreign salt is not fully deposited, the liquor is
clarified, and more water is added, sufficient to form ten parts,
including that which has already been poured upon it. The liquor
is removed, when it is clear and less heated, and put into copper
vessels, where it is agitated to prevent crystallization, and to
effect the pulverization of the saltpetre.

The saltpetre obtained by this process is not sufficiently pure.
The purification is completed by washing it with water saturated
with nitre, which dissolves the foreign substances. This washing is
completed in a vessel, the bottom of which has been pierced with
holes. The nitre, however, is left some hours in contact with the
water, when the latter is permitted to run out. When the solution is
of the same degree of concentration as that of the saturated water,
the operation is finished. The nitre is dried for use.

The old process of refining saltpetre is thus described: Put into a
copper, one hundred pounds of nitre, and fourteen gallons of water;
let it boil gently half an hour, removing the scum as it forms; then
stir it, and before it settles put it into filtering bags, which must
be suspended from a rack. Put under the filters glazed earthen pans,
to receive the liquor; in which place sticks for the crystals to form
on. In two or three days, it will all crystallize.

In some saltpetre works, sulphate of potassa is used with advantage.
This salt is furnished in abundance, by the combustion of a mixture
of nitre and sulphur, in the manufacture of oil of vitriol. It
forms the residue after the combustion. It is likewise produced in
the preparation of nitric acid, in the decomposition of nitrate
of potassa, by sulphuric acid. It may, therefore, be obtained in
quantity, from the oil of vitriol manufacturers, and the aquafortis
distillers. It is usually called _vitriolated tartar_.

It is known that sulphuric acid forms, with lime, an almost insoluble
compound, called sulphate of lime, or gypsum; and hence, when
sulphate of potassa is mixed with a solution of nitrate of lime,
nitrate of potassa is formed, which remains in solution, and sulphate
of lime is precipitated. The same effect takes place with all earthy
nitrates. For the application of sulphate of potassa, in this way, we
are indebted to M. Berard. It might be advantageously employed in
decomposing the calcareous nitrate of the nitre-caves of the western
country.

M. Longchamp has recommended the use of sulphate of soda, or
Glauber's salt, for decomposing the muriate of lime, which exists
occasionally in impure nitre. These two salts reciprocally decompose
each other; sulphate of lime is precipitated, and muriate of soda
remains in solution. The latter is separated by evaporating the
nitrous solution.

M. de Saluces (_Mémoire de l'Académie des Sciences de Turin,
Année, 1805 à 1808_,) has proposed a new process for purifying
nitre. It consists in filtering it through argillaceous earth, or
clay. Although the process is highly spoken of, yet we can see no
particular advantage it possesses.

Chaptal observes, that the process mostly in use is that of
dissolving 2000 pounds of crude saltpetre in a copper boiler, in 1600
lbs. of water. As the solution is made by the heat, the scum, which
forms, is taken off. Twelve ounces of glue, dissolved in ten pints of
boiling water, and mixed with four pails full of cold water, are then
added. This addition cools the solution. As to the manipulations of
the process, they have been given. The principal thing to be attended
to, is to separate the marine salt, which is done during the boiling.

To pass this saltpetre through a second operation, in order the
more to purify it, it is again dissolved, in the proportion of 2000
pounds, in one-fourth of its weight of water. Heat is applied. The
scum is separated; a solution of 8 ounces of glue in one or two pails
full of water is then added. After the solution becomes clear, it
is suffered to cool, and at the expiration of five days, it will
crystallize, or form in a mass, which is then exposed to the air six
or eight weeks to become completely dry.

In treating of the formation of nitre in France, Bottée and Riffault
(_Traité de l'Art de Fabriquer la Poudre à Canon_,) consider it under
the following heads:

1. _The constituent principles of nitre; its generation, and the
theories respecting it._ In this article, the composition of nitric
acid and its union with potassa, and the production of artificial
nitre, are taken into view.

2. _Nitrous earths, and substances which yield saltpetre._ This
subject comprehends a view of the substances, which contain
saltpetre, as well as those which afford it by nitrification.

3. _The preparation of the substances to produce saltpetre._ This
article relates to the manipulations required for the production of
nitre.

4. _The manner of lixiviating saltpetre earths._ The lixiviation is
an important part of the process, however simple it may appear; as
upon its accuracy depends the quantity of the product.

5. _The treatment of the different waters (lixiviums) with potash,
sulphate of potassa, and wood-ashes._ This article points out the use
of potash in decomposing the earthy salts, such as nitrate of lime;
of sulphate of potassa, which converts the nitrate of lime by double
decomposition into nitrate of potassa, the sulphate of lime being
precipitated; and of wood-ashes, which act in the same manner as
potash, as they contain this alkali.

6. _The evaporation of saltpetre waters, and the crystallization of
nitre._ In this article, they consider the separation of foreign
alkaline salts, as muriate of soda, and the crystallization of the
nitre, to obtain it in a state of purity.

7. _The treatment of the mother water of crystallization._ This
article refers to the manner of using the mother water, in order to
obtain more nitre from it, and its employment in lieu of fresh water
for other lixiviums.

8. _The refining of saltpetre by the old process._ They describe here
the old process, in which a variety of substances were used to purify
the saltpetre, but which is now generally abandoned, or laid aside.

9. _The process of refining saltpetre, as adopted in the
establishments of the administration._ Under this head they give, in
detail, the process employed throughout France, as uniform and the
same, in every refinery.

10. _The manner of proceeding in the examination of various kinds
of saltpetre in the magazines of the administration._ This article
relates to the different modes of examining saltpetre.

11. _On the manufacture of potash and pearlash._ This subject is
important, as potash is an indispensable article in the preparation
of saltpetre, and the formation of the alkali may be considered as of
primary magnitude in establishments, conducted upon so large a scale
as those of France.

It is thus, that a regular system is adopted, by the French
government, for the production of saltpetre; and we may add also, for
the manufacture of gunpowder, which we notice in that article.

It may be proper to mention some facts, respecting the formation of
nitre-beds, and the means adopted, in this way, to obtain saltpetre,
and to offer, at the same time, some observations on this mode of
obtaining nitre.

The _Mémoires de l'Académie des Sciences_, 1720, contain the
observations of M. Bouldoc, relative to the process of lixiviating
saltpetre earths. Lacourt published a pamphlet some years after,
entitled, _Instruction concernant la Fabrication du Saltpetre_.
Various dissertations appeared on the same subject. In 1775, the
French Academy of Sciences proposed a prize-question, which produced
a more thorough investigation. The Memoirs of Thouvenal, of the
Chevalier de Lorgna, and of MM. de Chevrand, and Ganivel, were
highly approved, some of which took the prize. Chaptal, who has done
more, perhaps, than any other person in France, to promote this
all-important object, published, in 1794, an excellent dissertation,
founded on experiment and observation. This Memoir was published in
the _Journal des Arts et Manufactures_, t. iii, p. 12.

Kirwan (_Geological Essays_, p. 143,) remarks, that the saline crust,
which is found on the walls of the houses of Malta, is owing to
the walls being built of fine grained limestone. When wetted with
sea-water, it never dries. The crust is nitrate of potassa, nitrate
of lime, and muriate of soda, and is some tenths of an inch thick.
Under this crust, the stone moulders into dust. When the first falls
off, it is succeeded by a second, and so on, until the whole stone
is destroyed. This particular effect, however, is attributed to the
presence of marine salt.

Mr. Kirwan observes, that, "M. Dolomieu shows, at the end of his
Tract on the Lipari Islands, that the atmosphere of Malta, in some
seasons, when a south wind blows, is remarkably fouled with mephitic
air; and, at other times, when a north wind blows, remarkably pure;
and hence, of all others, most fit for the generation of nitrous
acid." Mr. Kirwan remarks, "How the alkaline part of the nitre,
which is one of the products resulting from the decomposition of
this stone, is formed, is as yet mysterious: Is it not from the
tartarin lately discovered in clays and many stones?" He adds, after
speaking of animal and vegetable decomposition, "I should rather
suppose, that the alkali is conveyed into these earths by the putrid
air, than newly formed; and the reason is, that tartarin, (potash,)
notwithstanding its fixity, is also found in soot; and, in the same
manner, may be elevated in putrid exhalations."

Artificial nitre-beds consist of the refuse of animal and vegetable
substances, undergoing putrefaction, mixed with calcareous earth;
the refuse of old buildings, particularly plaster; earths from
the vicinity of inhabited buildings; blood, urine, &c. They are
covered, from the rain, by a shed, open at the sides. Cramer, an
author of credit, informs us, that he made a little hut, with windows
to admit the wind. In this, he put a mixture of garden mould, the
rubbish of lime, and putrid animal and vegetable substances. He
frequently moistened them with urine, and in a month or two found his
composition very rich in saltpetre, yielding at least one-eighth part
of its weight. The practice of obtaining nitre from nitre beds, was
followed in France and Germany. It is extracted and refined by the
process already given.

When oxygen gas is presented to azote at the moment of its
liberation, nitric acid is formed. As ammonia is the result of animal
putrefaction, or is formed in the process, hydrogen must unite also
with azote. The azote is furnished by the animal substances. These
facts being known, we are enabled to account for the generation of
nitric acid, and, consequently, of the earthy and other nitrates, in
artificial nitre beds.

In noticing this subject, it is unnecessary to quote the opinion
of Stahl, who believed that there was but one acid in nature, the
sulphuric; and that nitric acid was the sulphuric acid, combined
with phlogiston, which he affirmed was produced by putrefaction; nor
is it necessary to mention the opinion of Lemery, who believed that
nitre exists ready formed in animals and vegetables by the processes
of vegetation and animalization. The experiments of the French
philosophers have put these opinions at rest.

Thouvenal discovered, that nothing more was necessary for the
production of nitre than a basis of lime, heat, and open air; so that
nitre beds, formed of putrefying animal and vegetable substances,
with the conditions thus stated, must produce saltpetre; a fact which
experience abundantly justifies.

The process for the formation of nitre, is called _nitrification_.

Although animal substances, by putrefaction, furnish azote,
and nascent azote unites with facility with the oxygen of the
atmosphere, by which nitric acid is generated--(hence the
spontaneous decomposition of nitre composts)--yet Vauquelin is of
opinion, that the presence of calcareous or alkaline substances
is indispensable, and that the production of carbonate of ammonia
from the animal matter, is another compound, which results from
the same decomposition. Ammonia is produced by the union of azote
and hydrogen, and carbonic acid by that of carbon and oxygen. He
considers then, that the presence of lime, magnesia, potash, &c.
_determines_ the union of the azote with oxygen, and of course, the
formation of nitric acid; and as this acid unites with one or other
of these substances, according to circumstances, we have either
nitrate of lime, or of magnesia, or nitrate of potassa. The idea
that water is decomposed in the change which animal and vegetable
substances undergo, in the process of nitrification, is contrary
to observation; for the presence of air in dry situations, is
indispensable to the process.

If a compost, made up of animal, vegetable, and calcareous
substances, and put in small beds or heaps, and covered with a shed
open at both sides, be frequently turned to admit new surfaces to the
air, and occasionally moistened with urine, &c.--nitric acid will be
generated as the putrefaction goes on. When this process is suffered
to proceed until the decomposition is complete, and the beds then
lixiviated, the quantity of nitre will be considerable. In all cases,
we are to observe, that, as various earthy nitrates are produced,
and mostly nitrate of lime, potash, or wood-ashes which contain this
alkali, are to be used.

It was long since shown by Glauber, that a vault plastered over with
a mixture of lime, wood-ashes, and cows' dung, soon becomes covered
with efflorescent nitre; and that, after some months, the materials
yield, on lixiviation, a considerable proportion of this salt. M. de
Roder, speaking of nitrous walls, observes, that the efflorescence of
nitre on them is in consequence of the stone, lime, and sand employed
in the building.

What is denominated the _saltpetre rot_, is an efflorescence observed
on the walls of old buildings, and on the ground. Dr. C. F. Gren,
professor at Halle, in Saxony, (_Principles of Modern Chemistry_,
vol. ii, p. 128), very justly remarks, that, among the matters
capable of corruption, those are the most convenient in making
nitre, which contain the greatest portion of azote, of which animal
substances are the first; among which he enumerates flesh, blood,
skins, excrements of animals, old woolen stuffs, and urine. He also
mentions marsh plants, green herbs, mud from streets trodden by
cattle, and the ground from marshes or bogs. As a compost he adds,
that the ground from church-yards, where corpses have successively,
and during a long series of years, undergone corruption, would be
the best for artificial nitre beds. On the subject of nitre beds,
the reader may consult the _Recueil de Mémoires et de Pièces sur la
formation et la fabrication du saltpetre, à Paris_, 1786, 4to. These
remarks on the generation of nitre, although of more ancient date,
are confirmed by James and Herman Boerhaave, (_Chemistry, &c._)
Hoffman, (_de Salium Medicorum, et de Præstantissima Nitri Virtute_),
Stahl, (_de Usu Nitri Medico_), Neuman, (_chemical works_), and
Lewis, (_Materia Medica_)--all of whom have written more or less on
the formation of saltpetre; to which we may add the observations of
Parr, (_London Medical Dictionary_, vol. ii, p. 24.)

The process for extracting saltpetre from damaged gunpowder is
nothing more than putting it into a boiler, and adding water
sufficient to cover it. On applying heat, the nitre will be
dissolved. If any scum forms, it must be removed. When the solution
is effected, pour it on a sufficient number of filters, and collect
the fluid which passes through. The residue may be treated with more
water, and the whole again filtered. After boiling the solution, set
it aside to crystallize. The sulphur may be recovered, by subliming
the residue in a temperature not sufficient to inflame it. The
charcoal may be used again for the same purpose.

Saltpetre, when properly refined, does not contain any foreign salts,
and its purity may be known by a variety of experiments, as follows:
make a solution of the salt in distilled water, and filter it through
paper. Put a portion of it in a wine glass, and add a solution of
carbonate of potassa. To another portion, add a small quantity of
muriate, or in preference, nitrate of barytes. To a third portion,
add nitrate of silver. If the fluid in the first glass remains clear,
without any turbidness, we are to infer the non-existence of earthy
salts; if turbid, that it contains lime, or some other earth, either
in the form of a nitrate or muriate. The addition of oxalate of
potassa to another portion of the solution will show the presence
of lime by forming a precipitate, and the addition of carbonate of
ammonia, and then of phosphate of soda, will indicate magnesia. If
the second glass remains transparent, it shows that neither sulphuric
acid, nor any of the sulphates are present. If the fluid in the third
glass continues also clear, we infer that none of the muriates exist.
These experiments are sufficient to show the purity of saltpetre. It
would afford perhaps more satisfaction to institute also the same
experiments on other samples of nitre, by which a comparison may
be formed of the relative purity of each. To make an analysis of
the salt, with the view to determine the proportion of the foreign
substances would be altogether unnecessary for common purposes. A
regularly defined crystal would, in a great measure, point out its
purity. The double refined saltpetre is chemically pure. Artificers
determine the purity of nitre by its flame; if white, they call it
pure, if yellow, impure.

The same reagents may be used in the examination of gunpowder, as
we shall notice hereafter. If a portion of powder be mixed with
distilled water, the water will dissolve only the saline substances,
leaving the charcoal and sulphur. When the whole is thrown on a
filter, the fluid, which passes through, will contain the saltpetre,
and foreign salts, if any are present. The same experiments may
then be performed with the solution, and the quality of the nitre,
of which the gunpowder was made, be determined. Some gunpowder
absorbs a large portion of water, which is owing to the presence of
deliquescent salts. These salts may be detected by proceeding in the
way we have pointed out. The art of refining saltpetre is so well
known of late in the United States, especially by the Messrs. Dupont
of Brandywine, Delaware, that our gunpowder is of a very superior
quality. I have examined various specimens of this saltpetre, and
gunpowder made with it, and could not detect any of the sulphates
or muriates, either alkaline or earthy. For the manufacture of
gunpowder, and fire-works generally, the nitre, it may be observed,
cannot be too pure.

In pyrotechny, it is necessary to have the nitre in powder.
Pulverizing it in a mortar is a tedious method, if a large quantity
is required for use. There is an advantage, likewise, in the mode
we will describe; because the saltpetre, besides being extremely
fine, is made perfectly dry. Put into a copper kettle, whose bottom
must be spherical, fourteen pounds of refined saltpetre, with two
quarts or five pints of water. Put the kettle on a slow fire, and if
any impurities rise and form a scum, remove them; keep constantly
stirring with two large spatulas, till the water evaporates, and
the nitre is reduced to a powder. This will be perfectly white, and
almost impalpable. If it should boil too fast, remove the kettle, and
set it on wet sand, which will also prevent the nitre from adhering
to the pot. It should be kept in a dry place. This process of
powdering saltpetre is performed on a large scale for the manufacture
of gunpowder.

_Sec. II. Of Nitrate of Soda._

This salt has been recommended in lieu of nitre, for preparing
certain fire-works; but we confess, we can see no particular
advantage in using it. It has the property of attracting humidity
from the air, and on that account is rendered unfit for the
manufacture of gunpowder. This salt is composed of nitric acid and
soda. It was formerly called _cubic nitre_. It may be formed, very
readily, by saturating nitric acid with soda, and evaporating the
solution. It crystallizes in rhomboidal prisms. It may be formed more
economically, by mixing together the solutions of nitrate of lime and
sulphate of soda, filtering the mixture, and evaporating the filtered
liquor. It will be sufficient to observe, that it deliquesces, or
absorbs moisture, and in the fire, that its phenomena are the same as
those of nitre. It does not melt so readily.

Used in the same proportion as nitre, it will form a gunpowder, which
soon, however, spoils by exposure. It will, like nitre, communicate
a yellow colour to the flame of alcohol. Experiments were made with
this salt, with the view to the fabrication of gunpowder, by MM.
Bottée and Riffault. Their conclusions, as we have stated, may be
seen in their work on _gunpowder_. Professor Proust says, that five
parts of nitrate of soda, with one of charcoal, and one of sulphur,
will burn three times as long as common powder, so as to form an
economical composition for fire-works.

The _cubic nitre_, and the _nitrum flammans_ were known, and so
called, by the older chemists. The former we have seen, is the
nitrate of soda, and the latter, is a combination of nitric acid and
ammonia. Nitrate of soda, consists of 6.75 acid + 3.95 soda.

Nitrate of ammonia possesses the property of exploding; and, when
exposed to a temperature of about six hundred degrees, is decomposed,
furnishing the nitrous oxide, called also the protoxide of azote, and
exhilarating gas, besides water. Nitrate of ammonia is composed of
6.75 acid + 2.13 ammonia + 1.125 water.

_Sec. III. Of Chlorate of Potassa._

This salt, formerly called hyperoxymuriate of potassa, is used for
sundry preparations, and especially for experimental fire-works. It
is prepared by dissolving one part of carbonate of potassa in six
parts of water, and saturating it with chlorine, formerly called
oxymuriatic acid gas. This operation is usually performed in a
Woulfe's apparatus. The gas, as it proceeds from the retort or gas
bottle, is brought in contact with, and passes through, the fluid.
It is formed by pouring liquid muriatic acid on the black oxide of
manganese, or by pouring sulphuric acid on a mixture of muriate of
soda, and the black oxide. When the saturation is nearly complete,
crystals fall down. These being dissolved in boiling water, and the
solution allowed to stand, pure chlorate of potassa will be formed.

This salt is composed of 9.5, chloric acid, and 6 potassa; and
chloric acid is formed of 28.87, chlorine, and 32.28, oxygen. It
is to the oxygen in the salt, that its particular properties in
fire-works are to be ascribed.

This salt is decomposed by all combustible bodies, and detonations
generally accompany the decomposition. Hence it is used in a variety
of experiments, some of which we will give.

Three parts of the salt and one of sulphur detonate when rubbed in a
mortar. The same mixture, struck with a hammer on an anvil, produces
a loud explosion. Phosphorus detonates with this salt either by
trituration or percussion. The quantity of each should not exceed a
grain. Treated in the same manner with almost all the metals, the
same effect takes place. Cinnabar, antimony, pyrites, &c. produce
the same effect. Nitric acid, poured on a mixture of this salt with
phosphorus, produces flashes of fire. A mixture of the chlorate and
white sugar, when touched with sulphuric acid, immediately inflames.
Hence it is used in the preparation of pocket lights; the mixture
being put on a common sulphur match, and immersed in sulphuric acid.
The same preparation of sugar and chlorate of potassa, put over a
tube used for firing artillery, will set fire to the priming fuse, by
dropping on it sulphuric acid. Owing to this effect, M. Gassicourt
(_Archives des Découvertes_), recommended a similar mixture for
discharging cannon by means of this acid. As it contains a large
quantity of oxygen, that gas may be obtained from it by distillation.
Light decomposes it. It should, therefore, be excluded from the light.

As this salt, when mixed with inflammable substances, detonates when
struck with a hammer, it has been used for the purpose of inflaming
gunpowder without the use of the flint and steel. There are several
formulæ given for the purpose. We remarked, when treating of the
general theory of fire-works, that the Rev. Alexander Forsyth
discovered a new kind of gunpowder, which inflames merely by
percussion; that the gun-lock, which he contrived, was calculated
for firing cannon, as well as musquetry; that it was so contrived
as to hold forty primings of such powder; and that the act of
raising the cock primes the piece. In his composition, each charge
of priming contains no more than one-eighth of a grain of chlorate
of potassa. Since that period, it appears, that the lock, as well
as the powder, has been improved, although neither of them is in
general use. Thenard, (_Traité de Chimie_, tome ii, p. 559, troisième
édition), has given a formula for preparing a priming powder of this
salt, adapted to the new lock, which is made by mixing it with 0.55
of nitrate of potassa, 0.33 of sulphur, 0.17 of the raspings of
peach-wood passed through a fine sieve, and 0.17 of lycopodium, or
puffball. (See _Inflammable Powder_.)

This salt also produces powerful effects with charcoal and sulphur.
Three parts of it, with half a part of sulphur, and half a part
of charcoal powder, produce most violent explosions. Two persons,
in 1788, lost their lives by it. If this mixture be thrown into
concentrated sulphuric acid, a brilliant flame is produced. Such
mixtures, we are informed, will explode spontaneously. It should
not, for that reason, be kept prepared. Chlorate of potassa has
been used in the place of nitre, for the manufacture of gunpowder,
in consequence of its decomposition by charcoal. From its explosive
effects, M. Berthollet was induced to propose it as a substitute
for nitre. The proportions used by Chaptal, (_Chimie Appliqué aux
Arts_, tome iv, p. 198), are six parts of chlorate of potassa, one
of sulphur, and one of charcoal. They are to be mixed in a marble
mortar with a wooden pestle. The first experiment was made at Essone,
in France, in 1788. No sooner, however, had the workmen begun to
triturate the mixture, than it exploded with violence, and killed two
persons.

The force of this gunpowder is greater than that of the common sort;
but the danger of preparing it, and even of using it, is so great,
that these circumstances will always prevent its introduction. A
salt, containing so much oxygen, and so loosely combined, that even
the slightest friction, in contact with inflammable bodies, will
separate it, must, of necessity, prevent its use in that way.

The experiments, which were made at the arsenal at Paris, on the 27th
of April, 1793, comparing the effects of muriated powder, and the
superfine common powder, have given us the following results:

1st. By the eprouvette of Darcy, consisting of a cannon, which, being
suspended to the extremity of a bar of iron, described by its recoil
an arc, of which the degrees can be measured.

_Recoil._

2 drachms muriatic powder, 15 deg. 2/20
2 ---- do do moistened, 14 -- 1/20
2 ---- common powder, 10 -- 7/20
2 drachms common powder, 10 -- 1/20
3 ---- muriatic powder, 20 -- 9/20
3 ---- common powder, 16 -- 6/20

From these results, it appears, that, by the eprouvette of Darcy, the
muriated powder, or that prepared with chlorate of potassa, gave a
superiority of force of about one-fourth.

2nd. By the eprouvette of Regnier, which is repelled by the
explosion, to a distance greater or less, measured by the degrees of
the arc which it describes:

Muriated powder, 42
Idem, 51¾
Idem, moistened, 52
Common powder, superfine, 23
Idem, 22½

From which it results, that by the eprouvette of Regnier, the force
of the powder of the oxymuriate is double that of the nitrate, or
common powder.

M. Ruggieri is of opinion, that chlorate, or hyperoxymuriate of
potassa may be employed with advantage in the composition of rockets,
but we have not heard that it has been used. It is more powerful in
its effects, and probably for this reason he recommended it. This
salt, mixed with other substances, will produce the _green fire_ of
the palm-tree, in imitation of the Russian fire.

Chloric acid may be obtained in a separate state, by boiling the
compound solution formed by passing chlorine gas through a solution
of barytic earth, with phosphate of silver, which separates the
muriatic acid. By evaporation, the chlorate of barytes will
crystallize in fine rhomboidal prisms. When these crystals are
dissolved in water, and diluted sulphuric acid added by degrees,
an acid liquid will be obtained, which, if the sulphuric acid be
added cautiously, will be found entirely free from the latter acid
and barytes, and not affected by nitrate of silver. This is the
chloric acid dissolved in water. Chloric acid unites with sundry
bases. Combined with ammonia, it forms a fulminating salt, formerly
described by M. Chenevix. This salt is formed, by mixing together
carbonate of ammonia, and chlorate of lime. The carbonate of lime
is then separated by the filter, and the clear liquid, holding the
chlorate of ammonia in solution, is evaporated. Chlorate of ammonia
is very soluble in water and alcohol, and decomposed by a moderate
heat.

Chlorates, as the chlorate of potassa, are formed more readily
in the manner already stated: _viz._ by saturating the base with
chlorine, but in this case two salts are produced, the chlorate and
hydrochlorate. Chloric acid has also been obtained in a separate
state, from chlorate of potassa, by a process recommended by Mr.
Wheeler.

Perchloric acid, composed of seven primes of oxygen and one of
chlorine, is obtained from chlorate of potassa, treated in a
particular manner. Three parts of sulphuric acid and one of chlorate
of potassa, when heated, will give a saline mass, consisting of
bisulphate of potassa, and perchlorate of potassa. Deutoxide of
chlorine will be evolved. The perchlorate detonates feebly when
triturated with sulphur.

_Sec. IV. Sulphur._

Sulphur, or brimstone, is a principal ingredient in almost all the
compositions of fire-works. It should, therefore, be pure. The
flowers may be considered the purest kind of sulphur.

Sulphur is found native, either alone, or accompanying certain
minerals, such as gypsum, rock-salt, marl, and clay, as in
Switzerland, Poland, and Sicily. In the neighbourhood of
salt-springs, it is also found; and frequently in water, in
combination with hydrogen, forming the natural hepatic waters. It
is also found on the surface of the earth, as in Siberia. Volcanic
sulphur, or that which occurs in the fissures and cavities of lava,
near the craters of volcanoes, is very common.

Solfatere, Sicily, the Roman states, Guadaloupe, and Quito, in the
Cordilleras, are most celebrated for native sulphur. It has been
found in the United States, but in no quantity. We have a number
of mineral springs, which deposite sulphur. The Clifton Springs of
Ontario are of this kind. It occurs abundantly, in combination with
hydrogen, as sulphuretted hydrogen gas, in various parts of the
United States.

Native sulphur is abundant in the island of Java. It is obtained
from the now almost extinct volcano, about sixty miles from the
town of Batavia. At the bottom of the crater, there is said to lie
many hundred tons of native sulphur. Silliman (_Journal_, vol. i,
p. 58) observes, that it is in the crater of this volcano, that the
celebrated lake of sulphuric acid exists, "and from which it flows
down the mountain, and through the country below, a river of the same
acid."

Sulphur, however, is usually obtained from pyrites or metallic
sulphurets, by fusion and sublimation. It is usually denominated by
the name of the place whence it comes. Hence we have the Italian and
Sicilian sulphur; the crude, roche, or stone brimstone of Marseilles,
&c.

The quantity of sulphur, which may be obtained from the galena, or
sulphuret of lead, by sublimation, is considerable. Twenty-five per
cent is the loss sustained in the reduction of the lead ore, which
occurs so abundantly in the neighbourhood of St. Louis. When general,
the then lieut. Pike, (_Expeditions, &c. Appendix_) interrogated
Mr. Dubuque in 1805, respecting the quantity of lead obtained from
those mines, a detailed account of which is given by Schoolcraft,
he replied that the mineral would yield seventy-five per cent. of
lead, and hence the twenty-five per cent. loss must be the sulphur,
together with any foreign matter it may contain.

The experiments of M. Vauquelin, (_Annales de Chimie_, 1811) to
determine the quantity of sulphur contained in some metallic
sulphurets, show, at once, the proportion which may be obtained from
those combinations. Thus he found, that sulphuret of copper contains
21.31 per cent of sulphur; sulphuret of tin, 14.1; sulphuret of lead,
13.77; sulphuret of silver, 12.73; sulphuret of iron, 22; sulphuret
of antimony, 25; sulphuret of bismuth, 31.75; sulphuret of manganese,
74.5; and sulphuret of arsenic, 43.

Of native or prismatic sulphur, there are two species, the common and
volcanic. The former is of two kinds, the compact and earthy.

Sulphur, says Hanway, (_Travels, &c._) is dug at Baku on the western
side of the Caspian sea. It is found in the neighbourhood of the
celebrated naphtha springs, some of which form a mouth of 8 or 10
feet diameter.

Von Humboldt (_Annales de Museum National_) communicated to the
French national institute, that he discovered, in the province of
Quito, a bed composed of sulphur and quartz, in a mountain of mica
slate, and also sulphur in primitive porphyry. Kirwan (_Geological
Essays_, p. 143) observes, that sulphur promotes decomposition, by
absorbing oxygen, while it is thus converted into vitriolic acid; but
moisture is also requisite. He attributes, in the same manner, the
decomposition of stones that contain pyrites.

As the sulphur, which occurs in commerce, is chiefly obtained from
its native combinations, it may be proper to make some brief remarks
on this head. Sulphur in the state of combination is abundantly met
with, and in all countries. It is found in the state of sulphuric
acid, in various salts, as gypsum, epsom salt, native alum, &c.; and
united with metals, forming natural sulphurets, as in sulphuret
of iron, or iron pyrites, sulphuret of copper, or copper pyrites,
sulphuret of lead, or potter's lead ore, called also galena,
sulphuret of antimony, or crude antimony, sulphuret of zinc, or
blende, sulphuret of mercury, or cinnabar, sulphuret of arsenic, or
orpiment, &c. In fact, it appears to be a general mineralizer. It is
found also in some plants, and in animal substances.

Without detailing minutely the processes employed for extracting
sulphur from its combinations, which may be seen in Thenard, (_Traité
de Chimie_, tome i, p. 184) it will be sufficient to observe, that,
in general, pyrites, both of iron and copper, are arranged in
alternate layers in the form of a pyramid, and the _roasting_ is
continued for several months. Part of the sulphur is consumed, and
part is sublimed, and is condensed and collected in hollows, in the
upper part of the pyramid, whence it is removed several times a day.
It is also obtained from pyrites, by a kind of distillation. They
are reduced to coarse powder, and put into hollow iron cylinders, or
retorts, where the sulphur is disengaged and melted, and thence runs
into vessels of water. This process is employed in Saxony, where nine
hundred pounds of pyrites will yield one hundred to one hundred and
fifty pounds of sulphur, which is afterwards purified.

When melted and cast into wooden moulds, it forms the roll brimstone;
and, by sublimation, conducted in large chambers, as we shall
afterwards mention, it is converted into the flowers of sulphur. The
residue of the sublimation is _sulphur vivum_, which is also used in
fire-works. The roll brimstone is frequently adulterated.

In the island of Anglesea, it is obtained by the sublimation of the
yellow copper ore. The operation is conducted in kilns, and the
sulphur is conveyed by means of long horizontal flues, and collected
in large chambers. As the United States furnish an abundance of
martial pyrites, and also galena, sulphur might be manufactured in
this country, and advantageously, especially from galena, which is
very abundant in the neighbourhood of St. Louis. In the roasting
of the ore, all the sulphur is now lost, tons of which might be
collected.

For the purpose of gunpowder, the purer the sulphur, the better will
be the powder; hence attention is always paid to this circumstance.
M. Michel, one of the principal refiners of sulphur at Marseilles,
has improved the process for purifying sulphur for the purpose of
gunpowder. M. Libaw, connected likewise with the French national
powder establishment, has furnished a very useful and important
memoir on the same subject.

Two methods are proposed for the refining of sulphur, which we
will briefly state, namely, fusion, and sublimation. The first is
conducted in iron pots fixed in a furnace; and the sulphur, before
it is thrown in, is beaten into small pieces with a mallet. This
facilitates the fusion, and renders it more uniform. Small portions
at a time are thrown into the boiler, and stirred frequently with
a wooden spatula. This manipulation ought to be continued till the
boiler is filled. The heat must be regulated so as not to inflame, or
sublime the sulphur.

The sulphur of commerce is commonly of three different colours, viz:
citron-yellow, deep yellow, and brownish-yellow. These colours depend
on the different degrees of heat to which the sulphur was exposed,
in its extraction. The operation of refining consists in conducting
the fire in such a manner, as that the colour of the sulphur will
assume a brilliant yellow, bordering on a green. We must, therefore,
to produce this effect, operate on the sulphur according to its
colour. For the green sulphur, as little heat has been used for its
extraction, the fire may be left under the boiler until there is no
more left to melt than the top. The sulphur of the yellow colour may
be kept longer on the fire, which may be removed when the mass is
melted three-fourths. The sulphur of a brown colour, being already
much burnt, may be removed when the mass is melted one-half. If it
is required to operate on all the varieties at the same time, in
order to produce sulphur of a uniform colour, in that case we must
fill the boiler one-half with the green sulphur, one-fourth with the
yellow, and the remainder with the brown, and removing the fire when
the yellow is almost wholly melted. The boiler is then covered with
a lid. The fusion is completed by the heat of the mass. The light
bodies then raise themselves to the surface, forming a black scum,
which is removed, and the heavy bodies fall to the bottom. The boiler
remains for four or five hours, uncovering it from time to time to
take off the scum. The fluid part is removed, and is suffered to
congeal, taking care not to disturb the deposite.

The second process of refining is by sublimation. This operation
consists in subliming it in a close apparatus, which in sulphur
refineries are boilers placed in brick work, and furnished with
heads. These heads communicate by a pipe with a vaulted chamber,
placed at some distance from the furnace. The chamber serves to
collect the sulphur. There is usually a stone slab fixed between
the chamber and the head. The chamber is furnished with one or two
iron-plate valves. There is an opening in the head of each boiler,
in order to renew the sulphur: it is closed very tight by a plate of
iron. There is an opening also in the chamber, to admit a person,
which is closed likewise by an iron plate. The heads are luted before
the process is commenced.

By this process the sulphur is refined; for the pure part is
sublimed, and the foreign substances remain in the pots. The product
thus obtained is the ordinary flowers of sulphur. If the heat be
moderate, the sublimation is more perfect. It is necessary at
the same time that the temperature of the chamber should be low,
otherwise the sulphur will melt, which frequently takes place. Coarse
particles are separated from the flour, should they occur, by a sieve.

During the first part of the process, there is formed some sulphurous
acid gas, which is not produced after the vapour of sulphur forms the
atmosphere in the head. This is known to exist, by the acid taste of
the sulphur, and its black colour.

Detonation very frequently takes place, and sulphurous acid gas is
produced. In the sublimation of brimstone, about ten to eleven per
cent. is the usual total loss, of which six or seven per cent. is
residue. The acid may be separated from the sulphur by washing it in
water, and afterwards drying it. It is then called the washed flowers
of sulphur. (See _Traité de l'Art de Fabriquer la Poudre à Canon_, p.
153.) by MM. Bottée and Riffault, for a minute description of this
process.

Sulphur undergoes no change by exposure to the air. It is insoluble
in water. It breaks in the hand with a crackling noise. At 170
degrees it begins to evaporate, and when collected it is called
sublimed, or flowers of sulphur. It melts at 218 degrees. When
melted and poured into water, it forms the _sulphurs_ for taking
the impression of coin, &c. If melted, and cooled slowly, it will
crystallize in the form of needles. It is soluble in different
degrees in alcohol, ether, and oils. When sulphur is burnt very
slowly in the open air, it unites with oxygen and forms sulphurous
acid. This acid is used in bleaching. When mixed with nitre, and
burnt in leaden chambers, it forms sulphuric acid, or oil of vitriol,
by which process it combines with a larger quantity of oxygen. There
is another compound called hyposulphurous acid, all the salts of
which are inflammable and burn with a blue flame. Sulphur unites
with the alkalies, earths, and metals. If the alkaline sulphurets be
dissolved in water, and an acid added, the sulphur will precipitate
of a white colour, known by the name of milk of sulphur. It is
considered by some a hydrate of sulphur. The same preparation is
made by subliming sulphur in a vessel containing the vapour of
water. Sulphur unites with chlorine and iodine, forming chlorides,
and iodides. With hydrogen, it forms the sulphuretted hydrogen, or
hepatic gas, called also the hydrothionic and hydrosulphuric acid;
with carbon, the sulphuret of carbon; and with nitre and charcoal, in
the state of mixture, it constitutes gunpowder.

The motionless _ignes fatui_ of Italy, which are seen nightly on
the same spot, are attributed to the slow combustion of sulphur,
emitted through clefts and apertures in the soil of that volcanic
country; but the _Will-with-the-Wisp_, which moves in undulations,
near the surface of the ground, in swampy situations, and where the
putrefactive process is going on, originates in all probability
from decaying vegetable and other matters, and the extrication of
phosphorus. It is known that the acid of phosphorus is found in
plants, and especially those that grow in marshy places, in turf, and
several species of the white woods.

_Mealing of Brimstone._ What is termed the mealing of sulphur by
fire-workers, is no other than reducing it, if it be the roll, to
powder. Large mortars and pestles made of ebony, and other hard wood,
and horizontal mills with brass wheels are used. The _mealing table_
is used by artificers. It is generally made of elm, with a rim around
its edge four or five inches high. One end is narrow, and furnished
with a slider that runs in a groove, and forms part of the rim.
After using as much of the powdered brimstone as is required, copper
shovels being employed, the rest may be swept out at the slider. This
table is also used for the mealing of gunpowder and saltpetre. The
muller is generally made of ebony. After reducing it to powder, it is
then passed through a lawn sieve, furnished with a cover.

As brimstone is frequently adulterated with different substances,
it may be of importance to discover the fraud. We may remark, that,
if it is pure, it will be taken up entirely by chlorine gas, or by
using a solution of caustic potassa. The latter, however, cannot
be depended on in all cases. But the best mode, is that of melting
some of it in a ladle; if any residue remains, after the fumes have
ceased, the presence of foreign substances may be inferred, for
pure sulphur will sublime without leaving any residue. It is not
unfrequently adulterated with common flour. There is another mode of
determining the quality of sulphur, It should, if pure, be completely
soluble in boiling oil of turpentine. If any residue remain, we may
infer the presence of foreign substances, either vegetable, earthy,
or metallic.

It is obvious, that if the brimstone is impure, the effect of it in
fire-works will be imperfect. Flowers of sulphur, however, may be
almost always depended on. In all artificial fire, in which sulphur
forms a part, the _flame_ is more clear, as the sulphur is pure.

Several modes are recommended for the separation of sulphur from
charcoal, in gunpowder, which may be seen by referring to the
analysis, or chemical examination of gunpowder.

Sulphur constitutes one of the ingredients, generally speaking, of
incendiary compositions, used for military purposes, and, in such
cases, is usually mixed with pitch, tar, saltpetre, and sometimes
gunpowder. It is said to be one of the substances, which entered into
the composition of the ancient and celebrated Greek fire; but the
principal character of which, that of burning in water, was owing to
the presence of camphor. This substance, associated with sulphur,
pitch, and nitre, forms one of the most effective incendiaries of all
military fire-works. For such purposes, it is hardly necessary to
add, that the common roll brimstone is sufficiently pure.

As to the mode of preparing these works, the custom is to melt the
resinous substances first, then to add the sulphur, and finally the
saltpetre; and after the whole are melted and thoroughly mixed, to
remove the pot from the fire, and add gradually the gunpowder. If a
carcass is to be made, tow or hemp, or untwisted rope, is immersed in
the composition while hot, and taken out and formed into a ball of
the size required. Rope, treated in the same manner, with the same
composition, will make a more active tourteaux than the common kind.
(See _Carcass and Tourteaux_.)

All oils, whether expressed or essential, can dissolve sulphur.
To make this solution, the oil must be poured on the sulphur,
and sufficient heat applied to melt the substance. While the oil
dissolves the sulphur, it acquires a reddish or brown colour, an
acrid, disagreeable taste, and a strong fetid smell, somewhat
hepatic, resembling that of oil with sulphuric acid.

_Sec. V. Of Phosphorus._

We mention this substance, because it is used in some experiments,
although not in extensive fire-works. It is a very inflammable
substance, inflaming either by friction, or an increase of
temperature. It produces a most brilliant fire, and when mixed with
some substances, exhibits very pleasing phenomena. It usually comes
to us in sticks, which must be constantly kept in water to prevent
its inflammation. Phosphoric matches, phosphoric fire-bottles, &c.
are made of it. These are made in various ways. Phosphorus and
sulphur melted together in a small phial, forms the fire-bottle, or
some add a portion of lime. A sulphur-match dipped in this mixture
and gently rubbed, immediately inflames. They do not last any time,
in consequence of the acidification of the phosphorus. Phosphoric
tapers are usually made with a glass tube, on the breaking of which,
it inflames. When rubbed upon a wall in a dark room, it appears
very luminous. Dissolved in ether, and poured upon boiling water in
the dark, the vapour as it ascends appears remarkably luminous, and
has a pleasing effect. Dissolved in oil, as olive-oil, it forms the
phosphorized oil, which may be rubbed on the face and hands without
injury. This oil has the same appearance in the dark. The time of
night may be known by the light it produces. When mixed with nitrate
of silver, sulphuret of antimony, sulphur, chlorate of potassa, &c.
and struck with a hammer, it produces an explosion more or less loud.
A variety of explosive compounds may be made with it, but they must
be used with great care.

When combined with hydrogen, it inflames spontaneously when brought
in contact with atmospheric air. It inflames also in chlorine
gas. It is supposed to be the cause of the _ignes fatui_, or
_Will-with-the-Wisp_. The formation of phosphoretted hydrogen gas
may be shown in a variety of ways, as the following: throw some
pieces of phosphuret of lime into water, and bubbles of gas will
rise, which will take fire on coming to the air; or, put into a flask
some phosphorus, iron or zinc filings, water, and sulphuric acid,
and the gas will be generated; or, introduce into a small retort,
a solution of potassa, and a piece or two of phosphorus, and apply
heat, immersing the beak of the retort in a basin of water, the gas
will pass over, and inflame as it comes to the surface of the water.
In all these experiments, the water is decomposed; its oxygen goes to
a part of the phosphorus in the first experiment, and the hydrogen
of the water then unites with another portion of phosphorus, which
is then evolved; in the second experiment, the oxygen oxidizes the
metal, and the hydrogen dissolves a part of the phosphorus; and
in the third experiment, the phosphorus unites with the potassa,
forming a phosphuret, which decomposes the water, the hydrogen of
which passes off in combination with some of the phosphorus, forming
the phosphuretted hydrogen gas.

The cause of the spontaneous combustion is, that the oxygen of the
atmosphere unites with the hydrogen and the phosphorus, and forms
water and phosphoric acid; the latter producing a beautiful corona as
it rises in the air. The heat and light given out proceeds as well
from the oxygen gas, as from the phosphuretted hydrogen gas. When
saturated with oxygen, it is no longer inflammable.

There are some other experiments which can be made with this singular
substance.

It was formerly obtained from urine, as that fluid contains some
phosphoric salts. It is now prepared from bones. These are burnt to
an ash, and diluted sulphuric acid is poured on it; the phosphoric
acid it contains is then disengaged, and remains in the fluid. The
sulphate of lime is then separated, the fluid boiled to dryness, and
the dry mass is mixed with charcoal, and distilled in the open fire.

The phosphoric pencil, for writing on a wall, paper, &c. to be
luminous in the dark, is nothing more than a bit of phosphorus put
into a quill. It must be kept in water, and when used, frequently
dipped in water, to prevent its taking fire.

The _phosphoric_ stone of M. Bucholz, described in the _Archives
des Découvertes_, ii, p. 109, is a phosphuret of magnesia, prepared
by melting thirty grains of phosphorus in a small flask, and
adding twenty or thirty grains of calcined magnesia. Although this
process is given by Bucholz, yet, as it is difficult to prevent the
inflammation of the phosphorus, the best mode would be to bring the
vapour of phosphorus in contact with magnesia, in the same manner as
in preparing phosphuret of lime.

The pyrophorus of Wurzer is nothing than a phosphuret of lime. It is
prepared by taking two parts of pulverized quicklime, and one part
of phosphorus; introducing them into a bottle, and covering it with
three parts of quicklime, leaving one-third of the bottle empty; then
putting the bottle into a crucible surrounded with sand, previously
stopping the mouth with clay, and applying heat. Remove the phial
when the phosphorus appears to sublime of a red colour. When the
bottle is opened it becomes luminous, and brought out it inflames.

Phosphorus in the state of acidification, and united with lime, is
found in abundance. Whole mountains in the province of Estremadura
in Spain, are said to be composed of this combination. According
to Mr. Bowles, this stone is whitish and tasteless, and affords a
blue flame without smell when thrown upon burning coals. Mr. Proust
observes, that it is a dense stone, not hard enough to strike fire
with steel, and is found in strata, which always lie horizontally
upon quartz, and which are intersected with veins of quartz. He
adds, that it does not decrepitate on burning coals, but burns with
a beautiful green light. This stone is the common phosphorite. It
contains, according to Klaproth, 32.25 per cent. of phosphoric acid.

Several substances are known under the name of phosphorus, although
they do not contain it, such as Baldwin's phosphorus, or ignited
muriate of lime, Canton's phosphorus, or oyster-shells calcined with
lime, and Bologna phosphorus, or calcined sulphate of barytes.

_Sec. VI. Of Charcoal._

Charcoal performs an important part in all the various kinds of
fire-works. The facility with which it decomposes nitric acid, when
it is combined with salifiable bases, as with potassa in saltpetre,
and its action in all cases wherein nitre is concerned, are
sufficient examples of its effect.

Pure carbon is the diamond. It affords by combustion in oxygen gas,
the same gas as common charcoal, when charcoal is burnt in oxygen, or
in atmospheric air. This gas is carbonic acid, or fixed air. Charcoal
has been considered a long time an oxide of carbon, and according to
some, as Berthollet, a compound of carbon, hydrogen, and oxygen.

Charcoal is insoluble in water. It is not affected by the most
violent heat, if confined in close vessels. It is an excellent
conductor of electricity, but a bad conductor of heat. It is very
indestructible; and, therefore, when wood is charred, it will remain
a long time under ground without rotting. As an antiseptic, it is
powerful. It will therefore prevent the putrefaction of bodies,
and even recover tainted meat. As a preservative of water, for
sea-voyages, it has been long known. The charring of water casks is
designed for the same purpose. The quality of wine is said to be
improved by having the casks previously charred. It possesses the
property of absorbing gases, and to this property is ascribed its
use as an antiseptic, and its disinfecting quality. To the distiller
it is useful, as it destroys effectually the burnt or empyreumatic
smell of liquor. When heated to eight hundred degrees in the open
air, it burns. In oxygen gas the combustion is brilliant, forming in
both instances carbonic acid gas, called also aerial acid, fixed air,
mephitic air, and calcareous acid. This acid is formed in a variety
of processes, and is carbon saturated with oxygen.

Carbon exists in various states of combination, and many of the
compounds into which it enters are inflammable; hence carbonic
acid is generated in the combustion of coal, oils, fat, &c. In the
form of an acid, it is abundant in various stones, such as the
calcareous carbonates, as chalk, marble, limestone, and calcareous
spar, barolite, &c. all which effervesce with acids, the carbonic
acid being liberated. When limestone is burnt, to obtain quicklime,
the carbonic acid is disengaged, for the presence of this acid
distinguishes limestone from pure lime. Carbonic acid is generated
in various processes of nature as well as art. Hence it is produced
in the respiration of animals, and is found in a gaseous state in
wells, cellars, caverns, &c. It neither supports animal life, nor
combustion. In mines it is called choke damp; and the Grotto del
Cani, in the kingdom of Naples, has been long celebrated, on account
of it. This cave is in the side of a mountain, near the lake Agnano,
measuring not more than eighteen feet from its entrance to the inner
extremity; where if a dog or other animal that holds down its head be
thrust, it is killed by the gas. Some experiments were made in this
cave with gunpowder, which see. Carbonic acid, during the formation
of alcohol, in the vinous fermentation, is generated, and its
production appears to be designed by nature to carry off the excess
of carbon, which gives rise to that phenomenon called fermentation.
When combined with water, it forms aerated water, and with alkalies
and water, the aerated alkaline waters. Its union with bases forms
salts called carbonates. Plants have the property of decomposing it,
and in this respect nature has employed a mean of regenerating the
atmosphere, on the purity of which depends, in an eminent degree, the
very existence of animal life. The prime equivalent of carbonic acid
is 2.75, and carbonic acid is composed of carbon 0.75 + 2.0 oxygen.

Carbonic acid may be decomposed when combined with a base, as lime,
by phosphorus and heat, for charcoal and a phosphate of lime will be
produced. But carbonic acid in the state of gas may be decomposed by
potassium. Five grains of potassium will decompose three cubic inches
of gas, and be converted into potassa, producing at the same time
three-eighths of a grain of charcoal. If passed over a coil of fine
iron wire heated to redness, in a porcelain tube, and the operation
repeated, the iron will be oxidized, and the carbonic acid changed
into carbonic oxide gas.

Charcoal will not burn in dry chlorine. It unites with a less
proportion of oxygen, and forms carbonic oxide gas, which burns
with a deep blue flame. This combination is formed by distilling
in a red heat, a mixture of equal parts of iron filings and chalk.
This gas mixed with chlorine gas, and exposed to the sun's rays,
will unite with it, and form chlorocarbonic acid gas. Carbon unites
with azote, and forms cyanogen, the base of Prussic acid. It unites
likewise with hydrogen in two proportions, forming the hydroguret and
the bihydroguret of carbon, both of which are carburetted hydrogen
gases. The former is obtained by distilling a mixture of four parts
of sulphuric acid, and one of alcohol. The gas is very inflammable,
and burns with great splendour; and on that account may be used for
exhibition, in an apparatus similar to that of Cartwright. (See
_Fire-works with Inflammable air_.) It was called by the
German chemists olefiant gas. The other species, called also the
light carburetted hydrogen gas, may be obtained by agitating the mud
at the bottom of stagnant pools; and by the distillation of moist
charcoal, wood, pitcoal, pitch, or almost any animal or vegetable
substance. The gas, used for _gas-lights_, is the same. It is
usually obtained from pit coal. We may merely observe, that the gas
used for that purpose, _i. e._ for illuminating streets, theatres,
manufactures, &c. as obtained in the common method, is not altogether
the bihydroguret of carbon; but, according to the experiments of Dr.
Henry, a mixture of that gas with the hydroguret, and occasionally
carbonic oxide.

Carbon enters into other combinations. It exists as a component part
of gums, resins, sugar-starch, and other vegetable products, as the
vegetable acids, its union with iron forms steel, a substance greatly
used in the preparation of some fire-works, especially in some of the
_rains_ and _stars_, and in the composition of _brilliant fire_. (See
_Iron_.)

As charcoal enters into the composition of gunpowder, and the
effective force of powder depends considerably on the quality, as
well as the proportion of charcoal, it is obvious for this purpose,
it should be as pure as possible.

Carbon is always obtained from some of its combinations, as from
pitch, tar, rosin, wood, and oil. Various processes are employed for
this purpose. Thus, by the combustion of rosin and oil, as well as
pitch, tar, turpentine, &c. a soot is formed that collects, called
lampblack, which is nothing more than the carbon or charcoal. When
pit-coal is _charred_ in an oven, called a coke oven, all the bitumen
and sulphur contained in it are disengaged, and a charcoal remains,
called, however, _coke_. Wood, when charred is decomposed; all the
volatile parts are disengaged with carburetted hydrogen gas, and the
woody fibre is converted into coal. This coal is more or less dense
according to the compactness of the wood. Hard woods furnish the most
solid coal, and light woods on the contrary.

When the solid parts of animals, as bone, are charred, the volatile
products, principally ammonia or volatile alkali, are dissipated,
and there remains a substance called bone-black, improperly called,
_ivory black_.

The carbonization of wood in the common way is well known: after
it is cut to the lengths required, it is piled on the ground in a
pyramidal form, and covered with sod and clay, leaving a place for
the current of air, and the smoke. The wood is then set on fire, and
when the whole is burnt to a coal the vents, &c. are closed with sod
and clay.

Nicholson (_Chemical Dictionary_) observes, that in the forest of
Benon, near Rochelle, great attention is paid to the manufacture, so
that the charcoal made there fetches twenty-five or thirty per cent.
more than any other. The wood is that of the black oak. It is taken
from ten to fifteen years old, the trunk as well as the branches, cut
into billets about four feet long, and not split. The largest pieces,
however, seldom exceed six or seven inches in diameter. The end that
rests on the ground is cut a little sloping, so as to touch it merely
with an edge, and they are piled nearly upright, but never in more
than one story. The wood is covered all over about four inches thick
with dry grass or fern, before it is enclosed in the usual manner
with clay; and when the wood is charred, half a barrel of water is
thrown over the pile, and earth to the thickness of five or six
inches is thrown on, after which it is left four-and-twenty hours to
cool. The wood is always used in the year in which it is cut.

Turf or peat has been charred lately in France, it is said, by a
peculiar process, and, according to the account given in Sonnini's
Journal, is superior to wood for this purpose. Charcoal of turf
kindles slower than that of wood, but emits more flame, and burns
longer. It boiled a given quantity of water four times, while an
equal weight of wood charcoal boiled the same quantity but once. In a
goldsmith's furnace, it fused eleven ounces of gold in eight minutes,
while wood charcoal required sixteen. The malleability of the gold,
too, was preserved in the former instance, but not in the latter.
Iron heated red-hot by it, in a forge, was rendered more malleable.

In charring wood it has been conjectured, that a portion of it is
sometimes converted into a pyrophorus, and that the explosions that
happen in powder-mills are sometimes owing to this.

Bartholdi supposes, that such explosions are owing to the formation
of phosphoretted hydrogen gas, while others attribute them to the
absorption of oxygen, by the hydrogen contained in the coal, and the
consequent evolution of free caloric. Percussion, which necessarily
takes place in mixing the materials of gunpowder by stampers, no
doubt accelerates the combustion. The addition of water, and having
the charcoal previously pulverized, will prevent such accidents. (See
_Gunpowder_.)

Coal prepared in the manner above stated, is liable to many foreign
admixtures, nor can the process be so well regulated as to produce
coal of a uniform quality throughout. The present improved process
has many advantages, as experience has proved. It consists in
charring the wood in confined vessels, made of iron. These are
usually cylindrical, furnished with an iron cover, and placed in
furnaces. The pyroacetic, formerly called the pyroligneous, acid,
which is formed in the destructive distillation of wood, is caught
for use. This acid is useful to the calico printer, dyer, &c. in
making their iron liquor, and when purified, is employed in Europe in
the place of vinegar, as it is more pungent, and highly concentrated.

When pine and various kinds of wood, which yield turpentine, are
carbonized, we obtain tar during the process.

Chaptal informs us, that tar is obtained from the wood of the trunk,
branches, and roots of the pine, which are heaped together, covered
with turf, and set on fire to produce a close combustion, in the same
manner as for making charcoal. The oily parts which are disengaged,
trickle down, and are received in a gutter, which serves to convey
them to a tub. The most fluid part is sold under the name of huile de
cade; and the thicker part is the tar used for paying or painting the
parts of shipping and other vessels.

According to the wood submitted to the process of charring, the
products are, more or less, various; but in all cases it is only
the solid part, or ligneous fibre, that furnishes the coal. By the
ordinary process we obtain sundry volatile products, among which are
pyroacetic acid and carburetted hydrogen gas.

When wood is carbonized in the usual manner, it yields from 16 to 17
parts of charcoal in the hundred; but when the operation is conducted
in close vessels, the product is 28 per cent. a saving of eleven or
twelve per cent. By this difference in the quantity, it appears that
eleven or twelve per cent. is burnt in the common process.

M. Mollerat was the first who tried the experiment with iron
cylinders.

M. Vauquelin (_Annales de Chimie_, tome lxvi, p. 174) has given
some observations on the carbonization of wood in close vessels,
predicated on a Memoir of M. Mollerat; both of which are interesting.
The apparatus used by M. Mollerat is described by Thenard, (_Traité
de Chimie_, iii, p. 373,) to be composed of two parts, viz: a furnace
with a moveable dome, and a cylindrical kettle, or vessel of iron
sufficiently large to contain a cord of wood. It is furnished with a
cover and pipe. The pyroacetic acid is collected. Smaller cylinders
are preferred, because the wood is ignited more readily and the
charcoal is more of a uniform quality.

From 100 parts of the following named woods, Messrs. Allen and Pepys
(_Phil. Trans._ 1807) obtained the following proportional parts of
charcoal:

Beech 15.00
Mahogany 15.75
Lignum Vitæ 17.25
Oak 17.40
Fir 18.17
Box 20.25

See also the experiments of Mr. Mushet, in the third volume of
Tilloch's _Magazine_.

It appears by the _Annales de Chimie_, vol. 66, and the _Retrospect
of Discoveries_, vol. vi, p. 100, that three brothers have
established at Pellerey, near Nuits, Cote d'Or, a manufactory on a
large scale, for making charcoal in close vessels.

The quantity of charcoal they obtained is double that by the usual
mode, while it requires only one-eighth part of wood to be consumed
in the distillation; it is also better than the common, as a given
quantity evaporates one-tenth more water than the other; hence
iron masters may obtain twice as much iron from the use of a given
quantity of wood; and in addition to this, there is also prepared a
number of other articles, of each of which in order.

350 kilogrammes (700 lbs.) of wood, yield 25 or 30 of tar, which
retains so much acid that it is soluble in water; but when it is
washed, and rendered thick by boiling, for some time, it offers more
resistance to water. If mixed with one-fifth of rosin it is rendered
equally fit for the use of ships, &c. as the common tar.

Four sorts of vinegar are prepared, all of which are perfectly
limpid, which do not, like the common, contain any tartar, malic
acid, resinous or extractive matter, nor indeed any mineral acid,
lime, copper, or other substances. The simple vinegar marks--2°
hydrometer for salts, at 12° centigrade thermo. it is stronger tasted
than common vinegar, and produces a disagreeable irritation. The
aromatic vinegar is prepared with tarragon, the smell is agreeable,
but it has the same fault as the former. The vinous vinegar is formed
by adding some alcohol to simple vinegar; it has a very sensible
odour of acetic ether; the alcohol softens the flavour in some
degree, but the vinegar is still very sharp. The acid, called strong
vinegar, is in fact a very good acetic acid at 10-1/2° hydr., it is
very white, clear, and sharp, without the usual burnt flavour, and
seems to form the basis of the preceding kinds. It can be sold for
8 or 9 francs (7s.) per lb. which is only half the price of that
distilled from verdigris. Although not so agreeable to the taste as
common vinegar, these new kinds are more elegant to the eye, and do
not mother.

The editor of the Retrospect makes the following observations:

The proprietors of this manufactory seem to be perfectly aware of all
the several productions which could be prepared from the refuse of
their principal object; and we have no doubt but that the substances
they procure in this manner will amply compensate them for the use of
the capital that must be invested in building the furnaces.

The nature of the vessels in which they distil the wood is not
mentioned, but they are probably cast iron retorts, or vessels of a
similar nature, in which a distillation _per latus_ takes place. The
application, therefore, of lord Dundonald's furnaces for procuring
coke to this purpose would be still more advantageous.

A cubic yard of wood yields 100 quarts of acid liquor, besides 50 or
60 lbs. of thick oil.

The method of making charcoal of a _uniform quality_, for which a Mr.
Kurtz has taken out a patent, is the following:

A sheet-iron chest, which has a cover that fits it tight, and a pipe,
or tube, that descends nearly to the bottom, and coming out from its
side above, is fixed in brick work. In this the billets of wood are
put. Fire is then made underneath. It is obvious, that the wood is
kept at one temperature from its being immersed in vapour, as the
vapour cannot escape at the top, but must descend to the bottom,
and then proceed up the pipe, by which it is conveyed away. The
effect is, that the charring process goes on regularly, and the wood
is charred equally. The carbonization is finished when the vapour
ceases to appear, and nothing but carburetted hydrogen gas escapes.
The charring of bones is performed in iron cylinders, furnished with
tubes to receive, and convey away, the impure ammonia.

In the manufacture of powder, particular kinds of wood are selected
for carbonization. These are generally, willow, hazle, maple, poplar,
linden, buckthorn, or alder, or those which are tender and light,
because, as they are less dense, and consequently more friable,
they enflame and consume more rapidly: they are known in the arts
by the name of _white wood_. When a less sudden effect is to be
produced with the gunpowder, and the combustion prolonged, as in some
sky-rockets, the charcoal of hard wood is to be preferred, such as
the oak, beech, &c. When the wood is gathered, the bark is removed,
and the wood exposed to the sun to dry: it is then cut into billets,
and charred. The ashes, if any be formed, are to be carefully
separated.

In considering the use of charcoal, therefore, for the preparation
of gunpowder, we are to direct our inquiries to the choice of wood
for carbonization, and the best process for carbonizing it. All light
woods, we remarked, as the linden, willow, poplar, &c. furnish the
lightest coal, and on that account are preferred. It is remarked,
that tender wood, besides making a light, friable, and porous coal,
is more combustible than ordinary hard, and more compact wood, and
the coal that it furnishes leaves less residue after combustion.

Many experiments have been made with coal prepared from different
kinds of wood, with a view of ascertaining the kind best adapted
for the manufacture of gunpowder. M. Letort, at the powder mills
of Essonne, in France, instituted a number of experiments of this
kind. He made gunpowder with the coal of several kinds of wood, and
compared its effects by a mortar eprouvette. The result was, that
the powder made with the coal of poplar, was the strongest; and the
other powder, made with the coal of the linden, willow, &c. was of
the same quality throughout. As to the second inquiry, it is hardly
necessary to repeat, that for the complete and thorough carbonization
of the wood, to produce at the same time coal of a uniform quality,
the process of charring in iron cylinders or close vessels, is to
be preferred. The point to be attended to is, to bring the wood to
a complete state of ignition, and consequently to disengage all the
volatile or fluid parts. When the gas (carburetted hydrogen) ceases
to appear, it is a criterion that the operation is finished. This
gas, it is to be recollected, will come over even after the whole
of the wood is completely ignited. The first volatile product is
the pyroacetic acid. Some saturate the acid liquor with chalk, and
decompose the acetate of lime with sulphate of soda, and separate the
acetic acid from the acetate of soda by distillation with sulphuric
acid. The acetic acid is then tolerably pure, and may be diluted for
use.

It is observed, however, that when charcoal, prepared in iron
cylinders, is designed for gunpowder, the last portion of vinegar
and tar must be allowed to escape, and the reabsorption of the
crude vapours prevented, by cutting off the communication between
the interior of the cylinders and the apparatus for condensing the
pyroacetic acid, whenever the fire is withdrawn from the furnace. If
this precaution be not taken, the gunpowder made with the charcoal
would be of inferior quality.

On a large scale, when the object is also to prepare the vinegar of
wood, a series of cast-iron cylinders, about four feet diameter, and
six feet long, are built horizontally, in brick-work, so that the
flame of one furnace may play round about two cylinders. Both ends
project a little from the brick-work. One of them has a disc of cast
iron well fitted and firmly bolted to it, from the centre of which
disc an iron tube about six inches diameter proceeds, and enters at
a right angle, the _main_ tube of the refrigeration. The diameter
of this tube may be from 9 to 14 inches, according to the number of
cylinders. The other end of the cylinder is called the mouth of the
retort. This is closed by a disc of iron, smeared round the edge,
with clay lute, and secured in its place by wedges. The charge of
wood for such a cylinder is about 8 cwt. The hard woods, oak, ash,
birch, and beech, are alone used. Fir does not answer. The heat is
kept up during the day-time, and the furnace is allowed to cool
during the night. Next morning the door is opened, the coal removed,
and a new charge of wood is introduced. The average product of
crude vinegar is 35 gallons. Its total weight is about 300 lbs. But
the residuary charcoal, according to Ure, (_Chemical Dictionary_),
from whom we have taken this account, is found to weigh no more
than one-fifth of the wood employed. The crude pyroacetic acid is
rectified by a second distillation, in a copper still, in the body of
which about 20 gallons of viscid tarry matter are left for every 100.
Its acid powers are now superior to the best household vinegar in the
proportion of 3 to 2. Ure observes, that by distillation, saturation
with quicklime, evaporation of the liquid acetate to dryness, and
gentle torrefaction, the empyreumatic matter is so completely
dissipated, that on decomposing the calcareous salt by sulphuric
acid, a pure, perfectly colourless, and grateful vinegar rises in
distillation. Pyroacetic acid is said to be a powerful antiseptic. M.
Monge, Dr. Jorg, and more lately, Mr. Ramsay, of Glasgow, have made
experiments with it. Fish dipped in it have been preserved for many
days, and meat treated in the same manner, has also been preserved
from putrefaction.

With respect to the pulverization of charcoal, the operation is
so exceedingly simple, that we deem it unnecessary to notice it.
It is obvious, that mortars, mills, &c. may be used, with fine or
coarse sieves. For fire-works, charcoal is frequently pulverized
in a leather sack, in the same manner as grained powder is reduced
to meal-powder. It may be made either coarse or fine, to answer
different purposes, by employing sieves of different kinds. Charcoal
may be separated from nitre and sulphur, in gunpowder, by a simple
process, which may be seen by referring to the section on gunpowder.

The quantity of carbon in coal, is directly proportionate to the
quantity required for the decomposition of nitrate of potassa, a fact
necessary to be considered in the theory of the action of charcoal
in gunpowder. Thus, Mr. Kirwan found that, 12.709 of carbon are
necessary to decompose 100 of nitrate of potassa. It will be easy
to deduce the quantity of carbon, in a given weight of coal, from
the quantity of nitrate of potassa it is capable of decomposing. The
experiment is made very readily by fusing in a crucible, five hundred
or more grains of nitre, and when red-hot projecting by degrees the
powdered coal on the nitre. When the detonation produced by one
projection of coal has ceased, add a new portion till it produces no
farther effect.

Charcoal may be made intensely black, resembling ivory
black, according to M. Denys-de-Montfort, (_Bibliothèque
Physico-Economique_, for March 1815,) by pulverizing it very fine,
mixing it with wine lees, and drying the mixture, and then subjecting
it to a strong heat in a covered crucible, or other vessel.

_Sec. VII. Of Gunpowder._

Having remarked, that the quality of gunpowder depends upon the
purity of the materials, of which it is formed, and that they
should be prepared in a state of purity; the subject that will
now particularly claim our attention, is the proportions of the
ingredients, their mixture, and the final preparation of gunpowder
for use. To this, we purpose to add, the theory of its explosive
effects, the different modes of proving it, and the experiments
necessary to determine the quality of its respective ingredients,
on all which we will be as brief as the importance of the subjects
will admit. Previously, however, it may be interesting to notice the
_history of gunpowder_, the invention of which has so completely
changed the art of war.

The history of gunpowder has been fully treated by many writers of
eminence; but by none more largely, and, at the same time, more
satisfactorily than by the French. Beckman, in his History of
Inventions, is full on this subject. Our purpose is not to go into
details, as it would enlarge our volume, to the exclusion, perhaps,
of other and more important matter. We shall, therefore, confine
ourselves to a few facts and observations.

Notwithstanding much has been written on the subject, the original
invention of gunpowder seems to be in obscurity. By whom, and at what
time it was invented, is a question not fully settled. It is said to
have been known in the east from time immemorial, and whatever claim
Roger Bacon, who died in 1292, may have had to the discovery, or that
he knew the properties of gunpowder, it is certain, that the use of
fire-arms was then unknown in Europe.

Professor Beckman, who examined all the authors extant on the origin
of gunpowder, is of opinion, that it was invented in India, and
brought by the Saracens from Africa to the Europeans, who improved
the preparation of it, and employed it in war, as well as for small
arms and cannon.

M. Langles, who read a memoir on this subject to the National
Institute, in 1798, observes, that the Arabians obtained a knowledge
of gunpowder from the Indians, who had been acquainted with it from
the earliest periods. The use of it was forbidden in their sacred
books, the veidam or vede. It was employed in 690 at the battle near
Mecca. As nitre was employed in all probability in the Greek fire,
invented about the year 678, it is supposed, that that composition
gave rise to the invention of gunpowder.

Various prescriptions, or formulæ, have been given for the
preparation of this fire. The oldest is by princess Anna Commena,
in which, however, there is only resin, sulphur, and oil. Beckman
observes, that the first certain mention of saltpetre will be found
in the oldest account of the preparation of gunpowder, which, in
his opinion, became known in the thirteenth century, about the same
time that the use of the Greek fire, of which there were many kinds,
began to be lost. The oldest information on this subject is to be
found in the works of Albertus Magnus, and the writings of Roger
Bacon. The true recipe for making the Greek fire, and the oldest for
gunpowder, were found in a manuscript, preserved in the electoral
library at Munich. Various copies of this manuscript were made. Bacon
employed this writing, which was mentioned by Jebb, in the preface
to his edition, from a copy preserved in the library of Dr. Mead.
Whether the writer was Marcus Græcus, is of no moment; for Cardan
observes, that the _fire that can be kindled by water_, or rather not
extinguished by water, was prepared by Marcus Gracchus.

The former Marcus, mentions two kinds of fire-works; and the
composition, which he prescribes for _both_, is two pounds of
charcoal, one pound of sulphur, and six pounds of saltpetre, well
powdered and mixed together in a stone mortar.

Friar Bacon, who lived three centuries after Græcus, was in
possession of the recipe. It was concealed, however, from the people,
veiled in mystery. In his treatise _De Secretis Operibus Artis et
Naturæ, &c._ the secret of the composition is thus expressed: "sed
tamen salispetræ, LURU MOPE CAN URBE et sulphuris; et sic facies
tonitrum et corruscationem, si scias artificium." _Luru mope can
urbe_, is the anagram for _carbonum pulvere_. Bacon supposes, that it
was with a similar composition that Gideon defeated the Midianites,
with only three hundred men. Besides the use of gunpowder in the 9th
century, in the war between the Tunisians and the Moors, in which the
former are said to have employed "certain tubes or barrels, wherewith
they threw thunderbolts of fire," the Venetians employed it against
the Genoese, and it was reprobated as a manifest contravention of
fair warfare.

Peter Mexia, in his "_Various Readings_," relates, that the Moors,
being besieged, in 1349, by Alphonso the eleventh, king of Castille,
discharged a kind of iron mortars upon them, which made a noise like
thunder. This, with the sea-combat between the Tunisians and the
Moors, stated on the authority of don Pedro, bishop of Leon, places
the invention much earlier than by some writers.

Polydore Virgil ascribes the invention of gunpowder to a chemist,
who, having put some of his composition in a mortar, and covered it
with a stone, was blown up, in consequence of its accidentally taking
fire. The person here alluded to, according to Thevet, was a monk of
Friburg, named Constantine Anelzen. Others, as Belleforet, with more
probability, hold it to be Bartholodus Schwartz, or the black, who
discovered it, as some say, about the year 1320. Du Cange, however,
remarks, that there is no mention made of gunpowder in the registers
of the chamber of accounts in France, as early as the year 1338.
Roger Bacon knew of gunpowder, near one hundred years before Schwartz
was born. (See the invention of cannon, in _military fire-works_,
fourth part.)

It is certain, that Albert de Bollstædt indicated the constituent
parts of gunpowder, when he says, in his _Mirabilis Mundi_, "Ignis
volans, accipe libram unam, sulphuris, libras duas, carbonas salicis,
libras sex, salis petrosi, quæ tria subtilissime terantur in lapide
marmorea; postea aliquid posterius ad libitum in tunica de papyro
volante, vel tonitrum faciente ponatur.

"Tunica ad volandum debet esse longa, gracilis, pulvere illo optime
plena, ad faciendum vero tonitrum brevis, grossa et semiplena."

Gunpowder was of a much weaker composition than that now in use, or
that described by Marcus Græcus. Tartalgia, (_Ques. and Inv._ lib.
3, ques. 5), observes, that, of twenty-three different compositions,
used at different times, the first, which was the oldest, contained
equal parts of the three ingredients. When guns of modern
construction came into use, gunpowder of the present strength was
introduced.

The strength of powder depends upon the proportions of the
ingredients, they being pure; and Mr. Napier observes, (_Trans. Royal
Irish Academy, ii._) that the greatest strength is produced, when
the proportions are, nitre, three pounds, charcoal, nine ounces, and
sulphur, three ounces. The cannon powder was in meal, and the musket
powder in grain.

In the time of Tartalgia, the cannon powder was made of four parts of
nitre, one of sulphur, and one of charcoal; and the musket powder of
forty-eight parts of nitre, seven parts of sulphur, and eight parts
of charcoal; or of eighteen parts of nitre, two parts of sulphur, and
three parts of charcoal.

The intimate mixture, therefore, and the determinate proportions
of saltpetre, charcoal, and sulphur, form gunpowder; the different
qualities of which, depend, as well upon the proportions which are
used, as on the purity of the materials, and the accuracy with which
they are mixed.

Gunpowder is reckoned to explode at about 600° Fahr; but, if heated
to a degree just below that of faint redness, the sulphur will mostly
burn off, leaving the nitre and charcoal unaltered.

The saltpetre should be perfectly refined, and entirely free from
deliquescent salts; the sulphur as pure as possible, and, for that
reason, a preference should be given, to that which is sublimed, or
distilled; and the charcoal should be prepared in iron cylinders, as
described under that head, from woods, which are light and tender, as
the linden, willow, hazle, dogwood, etc.

There is a considerable difference in the proportions used by
different nations; but, from the many accurate and conclusive
experiments of the French chemists, their formula is certainly the
most perfect. In English powder, three-quarters of the composition
are nitre, and the other quarter is made up of equal parts of
charcoal and sulphur; but sometimes, to seventy-five parts of nitre,
fifteen of charcoal is used, adding ten of sulphur. Their government
powder is the same for cannon, as for small-arms.

According to a number of experiments, made at Grenille, it was
found, that the proportion of saltpetre in gunpowder, must be in a
given ratio with the charcoal, so that the latter might effectually
decompose it in the act of combustion; and hence the ratio is as 12
of the latter to 75 of the former, and these, with 12 of sulphur, are
the proportions generally employed. Ruggeri (_Pyrotechnie Militaire_,
p. 91,) gives, as the proportions, 12 parts of saltpetre of the third
boiling, 2 parts of charcoal, and 1 part of sulphur. The proportions,
used in Sweden, are 75 saltpetre, 9 sulphur, and 16 charcoal; in
Poland, 80 saltpetre, 8 sulphur, and 12 charcoal; in Italy, 76
saltpetre, 12 sulphur, and 12 charcoal; in Russia, 70 saltpetre, 11
sulphur, and 18-1/2 charcoal; in Denmark, 80 saltpetre, 10 sulphur,
and 10 charcoal; in Holland, 76 saltpetre, 12 sulphur, and 12
charcoal; in Prussia and Austria, 78 saltpetre, 11 sulphur, and 11
charcoal; and in Spain, 77 saltpetre, 11-1/2 sulphur, and 11-1/2
charcoal.

According to Klaproth and Wolff, (_Dictionnaire de Chimie_,
translated into French by MM. Lagrange and Vogel), Berlin powder
is composed of three-quarters nitre; one-eighth sulphur, and
one-eighth charcoal; Chinese powder, of 16 parts nitre, 6 charcoal,
and 4 sulphur; Swedish powder, of 75 parts nitre, 16 sulphur, and
9 charcoal; the powder of Lissa, of 80 nitre, 12 sulphur, and 8
charcoal; and English powder, on the authority of Beckman, as
follows: Powder for war, 100 parts of nitre, 25 charcoal, and 25
sulphur; musket powder, 100 nitre, 18 sulphur, and 20 charcoal;
pistol powder, 100 nitre, 23 sulphur, and 15 charcoal; strong cannon
powder, 100 nitre, 20 sulphur, and 24 charcoal; strong musket powder,
100 nitre, 15 sulphur, and 18 charcoal; and strong pistol powder,
100 nitre, 10 sulphur, and 18 charcoal. German powder, for war, is
composed, generally, of 0.70 saltpetre, 0.16 charcoal, and 0.14
sulphur. A small portion of gum is sometimes added, to make the grain
firmer; but such additions retard the combustion, and the effect.

The addition of gum arabic, however small, must injure the quality of
gunpowder, although it has the effect of making the grain firmer, and
less liable to fall into meal powder. The grain is also made heavier,
and less liable to absorb moisture. M. Proust, in his second memoir
on gunpowder, mentions the use of icthyocolla, a fish glue, for the
same purpose; and, nevertheless, speaks of some advantages that the
gunpowder, prepared with it, possesses.

It is observed by Mr. Coleman, of the Royal Powder Mills of Waltham
abbey, that it is not exactly ascertained, whether there is any
one proportion, which ought always to be adhered to, and for every
purpose. We have no hesitation in believing, for our own part, that
the French formula is the most correct, from the numerous experiments
made at the royal manufactory at Essone, near Paris.

A very considerable variation is found in the proportions of the
ingredients of the powder of different nations and different
manufactories. The powder made in England, is the same for cannon as
for small arms, the difference being only in the size of the grains;
but in France, it appears, that there were formerly six different
sorts manufactured; namely, the strong and the weak cannon powder,
the strong and the weak musquet powder, and the strong and the weak
pistol powder. The following are the proportions in each, though the
reason of this nicety of distinction is not very obvious. For the
strong cannon powder, the nitre, sulphur, and charcoal were in the
proportions of 100 of the first, 25 of the second, and 25 of the
third: for the weak cannon powder, 100, 20, and 24: for the strong
musket powder, 100, 18, and 20; for the weak, 100, 15, and 18: for
the strong pistol powder, 100, 12, and 15; for the weak, 100, 10, and
18.

The Chinese powder appears, by the analysis of Mr. Napier, to be
nearly in the proportions of 100 of nitre, 18 of charcoal, and
11 of sulphur. This powder, which was procured from Canton, was
large-grained, not very strong, but hard, well coloured, and in very
good preservation.

The following proportions are _now_ used in France, for the
manufacture of gunpowder for war, for hunting, and for mining.

For war. For the chase. For mining.
Saltpetre, 75.0 78 65.
Charcoal, 12.5 12 15.
Sulphur, 12.5 10 20.

After having made choice of the materials, the nitre being
pulverized, is passed through a brass sieve; the sulphur is
pulverized by means of a muller, or other contrivance, and also
sifted in a bolter; the quantities are then weighed, as well as the
charcoal.

The mixing of these substances is performed in a series of mortars,
hollowed out of a strong piece of oak wood; and by the aid of
pestles or stampers, which are set in motion by machinery and water
power, the mixture is thoroughly made. The end of the stampers is
usually covered with, and sometimes made of, brass, and the mortars
are also, in some powder mills, lined with brass. The mill has
generally two rows of mortars and stampers, of ten each. The nitre,
sulphur, and charcoal, in proper proportions, are put into each
mortar. The charcoal is first introduced into the mortar, being
sometimes previously pulverized; then wetted with water, and the
pounding is continued for thirty minutes. The nitre and the sulphur
are then added, and the whole is stirred with the hand. More water
is then added; it is again stirred, and the operation of pounding
is continued. The object of adding the water is to prevent the so
called volatilization of the ingredients, and to give the mixture the
consistency of paste, and at the same time to prevent the explosion
of the powder; a circumstance, which must be always guarded against.

After the operation is continued for half an hour, the pounders are
stopt, and the powder is then _re-exchanged_ by means of copper
or brass ladles; that is to say, the powder of the first mortar is
removed, and put into a box, and the contents of the second mortar
are put into the first, that of the third is put into the second,
that of the fourth into the third, &c. in succession, and in the
last, the contents of the first mortar.

We make, in this manner, twelve exchanges, allowing one hour between
two, and adding water from time to time, to the mixture, and
especially during the summer months. After this, the pounders are
again set in motion, for the space of two hours, and the operation
is finished. Fourteen hours are generally required to complete the
mixture, which is then in the form of paste. It is then granulated.
After being partially dried, the graining is performed by passing it
through sieves, which are more generally formed of parchment. These
sieves are made to work horizontally, and the powder is caught in
vessels placed beneath. The size of the grain depends on the sieve;
hence, fine grain, or coarse grain powder is thus obtained. In the
sieve is usually placed a contrivance to break the masses, and to
cause the powder to pass through in grains. After this, the powder
is again passed through a second sieve, commonly called a _grainer_,
the holes of which are of the same diameter as the powder we wish
to obtain. It is then put into another sieve, which permits only
the dust to pass, whilst the grain-powder remains. As the powder,
however, contains some grains too large, as well as others too small,
we may separate the former by a fourth sieve, of a suitable size.
The dust and fine grain are carried to the mill, and worked over.
The powder for war, and for mining, is dried immediately after the
graining.

Formerly, the powder was dried in the open air, by spreading
it on tables lined with cloth, or in oblong boxes; but serious
inconveniences resulted from it, and, particularly, the powdermakers
were obliged to watch the temperature, as well as the state of the
atmosphere. When the latter was moist, the _drying_ was suspended.

M. Champy, however, has obviated these inconveniences by a very
advantageous process, which consists in raising the temperature of
the air to 50 or 60 degrees, and causing it to pass from the chamber
in which it is heated, through cloths, on which is spread a bed of
powder, of a certain thickness. By this means, large quantities of
powder may be dried, in all seasons of the year, in a short time, and
at little expense. In whatever manner the _drying_ is performed,
there is always more or less _dust_ formed, which, to make the grain
of one uniform appearance, must be separated by a hair sieve. This
operation is called the _dusting_.

Whether we adopt the plan recommended by M. Champy, or heat the rooms
for the drying of powder to a certain temperature, by means of steam
pipes, a plan which presents every advantage, or use the old mode,
the effect is the same.

The musket, or _hunting powder_, undergoes an operation more than the
powder for war, namely, that of glazing, which is performed before it
is dried. With the exception of this process, it is made in the same
manner, using, however, a finer sieve in granulating it. The glazing
has for its object the smoothing, or removing the asperities of the
grain, and to prevent its falling into dust, and soiling the hands.

The powder intended for glazing is first exposed an hour to the
sun on one cloth, in winter, and between two cloths in summer, in
order to dry it more perfectly, which is very necessary before the
operation of glazing. For this purpose, it is put into a vessel like
a barrel, which is turned horizontally upon its axis, by machinery.
This barrel is furnished with bars that go across, intended to
augment the friction, or rubbing of the grain, and expedite the
process. The barrels are made to turn slowly, to avoid breaking the
grain, and at the expiration of eight or twelve hours, the glazing
is finished, the powder having acquired a sufficient hardness and
polish. After removing the powder, the dust is separated in the usual
manner.

_Gunpowder-mills_ are mills, in which powder is prepared, by pounding
and beating together the ingredients of which it is composed. They
are always worked by water-power, and as there are generally many
of them belonging to the same manufactory, one dam of water will
furnish a sufficient supply. In the construction of powder-mills, the
frame of the house is made very stout, and the roof put on lightly,
so that in case of explosion, it may be carried off easily, and
thus give vent to the powder, without much injury to the works. The
lights, to enable the work to be carried on at night, are placed on
the outside of the building, beyond the reach of the powder, and
by means of glass windows, the light passes into the mill. It is
lamentable, indeed, that so many accidents occur in the operation
of making powder. This may take place, as it has to our knowledge,
by the friction of the pounders. Their weight, the rapid succession
of the blows, and the dryness of the powder, are the principal
causes of such accidents, and sometimes by the inattention of the
workmen, suffering nails, and the like, to get among the materials.
I once witnessed the effect of an explosion of the kind, in the
neighbourhood of Frankford, in the vicinity of Philadelphia, at the
old and well-known powder mills, at that place. It was produced, in
consequence of the friction, by the neglect of the men not adding
water at a proper time, to keep the materials moist. The mill in
which the explosion took place was not much injured; but the roof,
together with the men, were sent a considerable distance. Some of the
latter fell into the mill-race, and were much injured. The effect,
however, did not stop here; for the fire communicated, strange as it
may appear, to some of the other mills, although at some distance,
and blew them up. Several explosions have happened at the same mills.

An experiment, made at the same works, by the then proprietor,
the father of the late commodore Decatur, by putting the nitre,
charcoal, and sulphur, into a barrel, with iron balls covered with
lead, which was turned upon its axis, terminated in the same way.
It exploded, but no other injury or accident was sustained. On
examining the balls, we found, that the lead was entirely worn off,
and the explosion must have been owing to the iron. This experiment
was performed, in order to find if the mixture could be made in this
manner, a plan which was afterwards adopted in France, with success,
but brass balls were used. In a series of essays, which I wrote
for, and published in, the Aurora, in 1808, on the "_Application
of Chemistry to the Arts and Manufactures_," as manufactures are
vitally important to the _practical_ independence of this country,
I mentioned the subject of gunpowder, and the different modes of
preparing it, and among which, the various experiments on this
subject.

The machinery, required in gunpowder mills, is exceedingly simple.
The power of the water, which may be given by an overshot, or
undershot wheel, is communicated to the parts of the mill, which
perform the work. Thus it is, that pounders, like the snuff, or
plaster-paris mill, are put in motion, by a horizontal shaft,
furnished, at different distances, with pieces of wood, which, by the
revolution of the shaft, and meeting with the projecting pieces from
the pounders, raises them in succession. They fall, then, in the same
order of succession, in the respective mortars.

The mortars of the powder-mill, are hollow pieces of wood, capable
of holding twenty pounds of paste, composed of the substances before
mentioned, which are incorporated by means of the pestle. There are
usually twenty-four mortars in each mill, where are made, each day,
four hundred and eighty pounds of gunpowder; care being taken, to
sprinkle the ingredients with water, from time to time, lest they
should take fire. This precaution is absolutely necessary, and if
attended to, would prevent many of the explosions, which, unhappily,
take place, in the manufacture of powder. The friction must be
great, and, therefore, the increase of temperature, occasioned in
this manner, ought to be guarded against. This can only be done, by
diminishing the time, or number of the blows, or by proportioning
the weight of the pestle, and the frequent addition of water. The
last is the most certain, and indeed, the water is in some respects,
necessary to promote a more intimate mixture of the materials. The
observations of M. David, on the use of water in the manufacture of
powder, are certainly correct. The pestle is a piece of wood, ten
feet high, and four and a half inches broad, armed at the bottom with
a round piece of metal. It weighs about sixty pounds.

Having mentioned one cause of the explosion of powder-mills, that
of friction produced by the pestle, we find that it has been
accounted for on another principle. The _Annales de Chimie_, tome
xxxv, mentions some instances of spontaneous combustion in powder
mills. It is well known, that charcoal has the property of absorbing
several gases, and the observations of Rouppe and Berthollet, on
this subject, are conclusive. It is also known, that charcoal, which
contains hydrogen, when exposed to atmospheric air, will absorb
oxygen, and form water; and during this combination, heat must be
generated, by the emission of caloric from the oxygen gas. It is
said, then, that in cases of spontaneous combustion, when nitre,
sulphur, and charcoal, are mixed together, (unless water be added to
prevent it), this effect will ensue, and fire be produced. We know,
however, that percussion is one source of heat; and in truth, if that
opinion be well founded, percussion itself may facilitate the union
of hydrogen, with the oxygen of the air, and necessarily operate as a
secondary cause of such explosions.

Another opinion has been advanced by Bartholdi, to account for
the spontaneous combustion in powder mills: namely, that charcoal
sometimes contains phosphorus, combined with hydrogen, which, by the
action of the pestle, is disengaged in the form of gas, and inflames,
the moment it comes in contact with the air. Others again suppose,
that it sometimes contains pyrophorus.

Pulverizing the charcoal, in the first instance, by itself, and
adding water, during its mixture, from time to time, a measure
proposed in 1808, by M. David, and now generally adopted, will
prevent such accidents; for it appears, they have not occurred in
France, since the adoption of this plan. Some remarks on spontaneous
combustion, may be seen in the article on _artificial volcanoes_.

M. Sage, (_Journal de Physique_, vol. lxv, p. 423, or _Nicholson's
Journal_, vol. xxiii, p. 277), has written on the spontaneous
ignition of charcoal, and adduced some facts on the subject; by which
it appears, that M. de Caussigni was the first, who observed, that
charcoal was capable of being set on fire, by the pressure of mill
stones.

Mr. Robin, commissary of the powder mills of Essonne, has given an
account, in the _Annales de Chimie_, of the spontaneous inflammation
of charcoal, from the black berry bearing alder, that took place
the 23d of May, 1801, in the box of the bolter, into which it had
been sifted. This charcoal, made two days before, had been ground in
the mill, without showing any signs of ignition. The coarse powder,
that remained in the bolter, experienced no alteration. The light
undulating flame, unextinguishable by water, that appeared on the
surface of the sifted charcoal, was of the nature of inflammable gas,
which is equally unextinguishable.[17]

The moisture of the atmosphere, of which fresh made charcoal is
very greedy, appears to have concurred in the development of the
inflammable gas, and the combustion of the charcoal.

It has been observed, that charcoal powdered and laid in large heaps,
heats strongly.

Alder charcoal has been seen to take fire in the warehouses, in which
it has been stored.

About thirty years ago, M. Sage saw the roof of one of the low wings
of the mint set on fire by the spontaneous combustion of a large
quantity of charcoal, that had been laid in the garrets.

Mr. Malet, commissary of gunpowder at Pontailler, near Dijon, has
seen charcoal take fire under the pestle. He also found, that when
pieces of saltpetre and brimstone were put into the charcoal mortar,
the explosion took place between the fifth and sixth strokes of the
pestle. The weight of the pestles is eighty pounds each, half of this
belonging to the box of rounded bell metal, in which they terminate.
The pestles are raised only one foot, and make forty-five strokes in
a minute.

"In consequence of the precaution now taken," M. Sage observes,
"to pound the charcoal, brimstone, and saltpetre separately, no
explosions take place; and time is gained in the fabrication, since
the paste is made in eight hours, that formerly required four
and-twenty.

"Every wooden mortar contains twenty pounds of the mixture, to which
two pounds of water are added gradually. The paste is first corned:
it is then glazed, that is, the corns are rounded, by subjecting them
to the rotary motion of a barrel, through which an axis passes: and
lastly, it is dried in the sun, or in a kind of stove.

"Experience has shown, that brimstone is not essential to the
preparation of gunpowder; but that which is made without it falls
to powder in the air, and will not bear carriage. There is reason
to believe, that the brimstone forms a coat on the surface of the
powder, and prevents the charcoal from attracting the moisture of the
air.

"The goodness of the powder depends on the excellence of the
charcoal; and there is but one mode of obtaining this in perfection,
which is distillation in close vessels, as practised by the English.

"The charcoal of our powder manufactories is at present prepared in
pots, where the wood receives the immediate action of the air, which
occasions the charcoal to undergo a particular alteration."

In 1724, (_Coll. Academ._ t. v, p. 413,) M. de Moraler proposed a new
mode of mixing the materials for gunpowder. In 1759, M. Musy proposed
another method to prevent explosions; and in 1783, the baron de
Gumprecht constructed a very ingenious powder mill, a model of which
he presented to the king of Poland, whose approbation it received.

There is an account in detail, of the results of the experiments made
by MM. Regnier and Pajot Laforet, with different fulminating powders,
in the _Archives des Découvertes_, iii, p. 337. These experiments,
although interesting in a philosophical view, cannot be of service in
the present case. They were made with gunpowder, fulminating silver,
fulminating silver and mercury combined, fulminating mercury alone,
&c. See also the _Bulletin de la Société d'Encouragement, cahir 65_.

The observations of M. Proust (_Journal de Physique_ for May,
1815) on the mixing of powder, and the consequences that result by
following the old process, may be consulted.

The process of manufacturing gunpowder, which we have described, is
followed in all, or the greater part of the factories of France. It
is, however, tedious, and not exempt from danger. The same process,
with some modifications or improvements, is adopted in this country;
but of all our gunpowder manufactories, that of the messrs. Dupont
of Brandywine, Delaware, has heretofore produced the best powder.
Powder, however, equally powerful, has been made in other factories.

The improved process of M. Champy, which, in many respects, is
superior to the foregoing, is the following:

1. The nitre, sulphur, and charcoal are first reduced, separately,
to very fine powder. This operation is performed in barrels, which
are made to turn upon their axis, similar to the barrel-churn, and
the substances are introduced gradually. Balls, made of an alloy of
copper and tin, are then put in, which by their action reduce the
substances to powder.

2. The second operation has for its object, the intimate mixture of
the ingredients. The quantities to be mixed are weighed, and put
into a drum with a quantity of shot, which is made to revolve during
an hour and a quarter. In this manner, three hundred pounds of the
mixture are at once operated upon.

3. The mixture is then moistened with water. About fourteen per cent.
is added. It is then passed through a sieve made with round holes,
and then put into a drum, and submitted for a half hour, to a rotary
motion. A number of small round grains are thereby formed, which are
separated from the mass by means of a sieve, the holes of which are
very small.

4. When a sufficient quantity of these grains are procured, they are
put into another drum, of a suitable size, with one and a half times
their weight of the original mixture. The drum being put in motion,
some water is added, which serves to make them increase in size, by
constant rubbing: at the end of a certain time, the whole becomes
granulated, or perfectly round. The density of the grains depends on
the mixture, and the time they were kept in motion.

5. The powder being thus grained, is passed through sieves, whose
holes are of different diameters; and hence it is divided into three
kinds: _viz._ cannon powder, musket powder, and fine grained powder.

6. Finally, the powder is dried, and preserved in the usual manner.
Its strength is equal to that made by the old process, and is
perfectly round.

It may be proper to observe, that this process presents many
important and decided advantages. Although, in our description, we
have not gone into details, yet the whole operation will be seen at
one view. It was practised in France, by its inventor, M. Champy,
and, besides being introduced into the United States, it has also
been adopted in Prussia.

M. Proust endeavoured to show, that charcoal made of shoots or
branches, makes the best powder, and will mix with more facility with
the nitre and sulphur; and in employing the ordinary charcoal, two
hours beating is necessary to obtain a perfect mixture. The pestles,
as Chaptal observes, usually make fifty-five strokes in a minute.
Their weight is various; he gives them at eighty pounds.

M. Carney discovered a new process for the fabrication of powder,
and although Chaptal himself made some advantageous changes in the
process, yet the merit of the discovery he gives entirely to Carney.
The process of M. Champy, is in some particulars the same. It will be
sufficient, however, to observe, that it is reduced to three heads:
_viz._

1. The pulverization, and sifting of the materials;

2. Mixing the materials intimately in vessels similar to casks; and,

3. Giving the mixture the necessary consistence, and the final
granulation.

For some details of the process, the reader may consult Chaptal's
_Chimie Appliqué aux Arts_, tome iv, p. 145.

Chaptal is of opinion, that Carney's mode of fabricating powder,
presents many advantages, among which he considers the facility of
its formation, economy in the expense, and the superiority of the
powder. In a memoir on the subject, and the formation of powder at
Grenelle, Chaptal has described the process very minutely.

Bottée and Riffault reduce the manufacture of gunpowder in France to
the following heads:

1. The mixture of the ingredients. This relates to the manner of
uniting the nitre, charcoal, and sulphur, the quantity of the
composition put into each mortar, and observations respecting the
manipulation.

The time required for reducing gunpowder to its proper consistency,
and for effecting the mixture is termed by the French, _Battage_.
They are usually twenty-four hours, (or eight according to the new
mode,) in pounding the materials to make good gunpowder. Supposing
the mortar to contain sixteen pounds of composition, it would require
the application of the pestle 3500 times each hour.

The order in which they are beaten, and mixed, is as before given,
and also the rechanging, or transferring the materials from one
mortar to another.

2. _Granulation_, (_Grenage Fr._) This operation consists, as before
observed, in passing the mixture through different sized sieves,
employing also parchment sieves, and afterwards separating the
dust by a fine sieve. The size of the grain depends altogether on
the sieve. Hence we have cannon-powder, gunning or musket-powder,
pistol-powder, and mining-powder. Superfine powder is the very small
grained.

3. _Glazing._ (_Lissage Fr._) This operation takes off the asperities
of the grain, renders it hard and less liable to soil the hands, and
gives it a kind of lustre. It is only used for fine powder, such as
the pistol, and hunting-powder. Cannon powder is never glazed. It is
performed in a barrel-shaped vessel, which is made to revolve on its
axis, like the ordinary barrel-churn. The quantity of powder glazed
in one of these barrels at a time, in France, is 150 kilogrammes.

By the rotary motion, the grains of powder rub against each other,
by which each grain becomes smooth, and receives a polish. According
to the motion of the barrel, so is the glazing more perfect. This,
however, is regular. After the operation, which continues several
hours, the dust is separated from the grain by a sieve. The state of
the atmosphere influences the process. If dry, the grain receives a
better polish; if wet or damp, the operation is retarded, and the
gloss imperfect. It has been customary to introduce a very small
portion of finely pulverized plumbago, (carburet of iron), in order
to give the grain a better polish. But such additions, however small,
are obviously injurious to the powder. It is said that it prevents
the absorption of moisture. Powder, which has been glazed with black
lead, (plumbago), may be known by its peculiar shining lustre, and
also by experiment. M. Cagniard Latour made some experiments with
glazed powder, which may be seen in the work of Bottée and Riffault,
p. 233.

4. _Drying._ (_Séchage. Fr._) The drying of powder is performed in
two ways, _viz._ by exposure to the sun, and by exposure to heat in
close rooms. The English mode, that of drying by steam pipes, MM.
Bottée and Riffault are of opinion, presents many advantages, and
particularly that the powder may be dried in all weathers, and with
perfect safety.

The mode of drying gunpowder by the vapour of water, (confining
it, however, in iron pipes or vessels,) was suggested in 1781, and
1787. See _Mémoires de l'Académie des Sciences de Suede_, 1781, the
_Journal des Savants_, 1787, and the _Transactions of the Society of
Arts_, vol. xxiv. Mr. Snodgrass, in the last work, gave an account of
a method of communicating heat by steam, by using pipes of cast iron,
for which the society of arts voted him forty guineas.[18] Chaptal
(_Elements de Chimie_) has some judicious remarks on the exsiccation
of powder.

The experiment made at Essonne near Paris, by M. Champy, in 1808,
on a contrivance for the drying of powder, was satisfactory. This
experiment may be seen in page 242 of Bottée and Riffault.

5. Dusting, (_Epoussetage_.) This operation is confined merely to the
sifting. It is nothing more than the separation of the dust from the
grain, which we have before noticed. The dust is put in the mortars,
and worked over.

6. _Barrelling &c._ After the powder has gone through the several
operations described, it is then put into barrels, and taken to the
magazine.

After speaking of gunpowder under these heads, they describe the
manner of treating the green, (_verd_) and dry meal powder; the
police of powder establishments, for order and economy; the workmen
necessary in a powder manufactory;[19] the process of making powder
in the revolution; and for the manufacture of _imperial powder_
(which contains 0.78 saltpetre 0.10 sulphur, and 0.12 charcoal); the
process of Berne, where the powder is made of 0.76 saltpetre, 0.14
charcoal, and 0.10 sulphur; the process of Mr. Champy, noticed in
this article; observations respecting different processes; on powder
magazines; gunpowder made of other saline substances besides nitre;
different modes of proving powder, examination of powder; description
of workshops, mechanics, and utensils, &c. &c. with a variety of
engravings. We have merely to remark, that this work of Bottée and
Riffault (a large quarto volume, of 340 pages, besides the plates,
which make a distinct volume) ought to be in the possession of every
gunpowder manufacturer, as it contains all the information known on
that subject. Of this fact there can be no difference of opinion,
that in consequence of the great attention paid to the subject of
gunpowder in France, not only by the government, but by scientific
associations and individuals, their knowledge generally must be more
minute and accurate, and their works, as authentic records of facts,
_more to be depended on_.

Besides many interesting works, and memoirs in French,[20] there have
appeared some valuable dissertations in the English language. Mr.
Coleman, in his paper in the Phil. Mag. ix, p. 355, may be considered
the first, who, as superintendant of one of the Royal powder mills,
was enabled to present a body of facts on this subject.

As the mode of manufacturing gunpowder at the Royal Powder Mills
of Waltham Abbey, in England, may be interesting and useful, in
connection with the different processes already given; we will
introduce in this place the account of Mr. Coleman, having extracted
it from the _Artist's Manual_, &c. of the author, and having taken it
from the original memoir of that gentleman.

The ingredients of gunpowder are taken in the following proportion,
namely, 75 of saltpetre, 15 of charcoal, and 10 of sulphur. The
saltpetre used is almost entirely that which is imported from the
Indies, which comes over in the rough state mixed with earthy
and other salts, and is refined by solution, evaporation, and
crystallization. After this it is fused in a moderate heat, so as
to expel all the pure water, but none of the acid, and is then fit
for use. The great use of refining the nitre is to get rid of the
deliquescent salts, which by rendering the powder made of it liable
to become damp by keeping, would most materially impair its goodness.
The sulphur used is imported from Italy and Sicily, where it is
collected in its native state in abundance. It is refined by melting
and skimming, and when very impure, by sublimation. It should seem
that the English sulphur, extracted in abundance from some of the
copper and other mines, is too impure to be economically used for
gunpowder, requiring expensive processes of refining.

The charcoal formerly used in this manufacture was prepared in the
usual way of charring wood, piles being formed of it and covered with
sods or fern, and suffered to burn with a slow smothering flame. This
method however cannot with any certainty be depended on to produce
charcoal of a uniformly good quality, and therefore a most essential
improvement has been adopted in this country, to which the present
superior excellence of American powder may be in a good measure
attributed, which is, that of enclosing the wood, cut into billets
about nine inches long, in iron cylinders placed horizontally, and
burning them gradually to a red heat, continuing the fire till every
thing volatile is driven off, and the wood is completely charred. But
as the pyroligneous acid, the volatile product of the wood heated
_per se_, is of use in manufacture, it is collected by pipes passing
out of the iron cylinder, and dipping into casks where the acid
liquor condenses. This acid is used in some parts of calico-printing,
chiefly as the basis of some of the iron liquors and mordants for
dark-coloured patterns. The wood before charring is barked. It is
generally either alder or willow, or dog-wood, but there does not
appear to be any certain ground for preferring one wood to another
provided it be fully charred.

The above three ingredients being prepared, they are first separately
ground to fine powder, then mixed in the proper proportions, after
which the mixture is fit for the important operation of thoroughly
incorporating the component parts in the mill. A powder mill is a
slight wooden building, with a boarded roof, so that in the event of
any moderate explosion, the roof will fly off without difficulty,
and the sudden expansion will thus be made in the least mischievous
direction. Stamping mills were formerly used here, which consisted
simply of a large wooden mortar, in which a very ponderous wooden
pestle was made to work, by the power of men, or horses, or water,
as convenience directed. These performed the business with very
great accuracy, but the danger from over-heating was found to be so
great, and the accidents attributable to this cause were so numerous,
that stamping mills have been mostly disused in large manufactures,
and the business is now generally performed by two stones placed
vertically, and running on a bed-stone or trough.

The mixed ingredients are put on this bed-stone in quantities not
exceeding 40 or 50 pounds at a time, and moistened with just so
much water, as will bring the mass in the grinding to a consistence
considerably stiffer than paste, in which it is found by experience
that the incorporation of the ingredients goes on with the most ease
and accuracy. These mills are worked either by water or horses.

The composition is usually worked for about seven or eight hours
before the mixture is thought to be sufficiently intimate, and even
this time is often found, by the inferior quality of the powder, to
be too little. The fine powder manufactured at Battle in Sussex, is
still however made in large mortars or stamping mills, in the old
way, with heavy lignum vitæ pestles. Only a very few pounds of the
materials are worked at a time.

The composition is then taken from the mills and sent to the
_corning-house_, to be corned or grained. This process is not
essential to the manufacture of perfect gunpowder, but is adopted on
account of the much greater convenience of using it in grains than
in fine dust. Here the stiff paste is first pressed into hard lumps,
which are put into circular sieves with parchment bottoms, perforated
with holes of different sizes, and fixed in a frame connected with
a horizontal wheel. Each of these sieves is also furnished with a
_runner_ or oblate spheroid of lignum vitæ, which being set in motion
by the action of the wheel, squeezes the paste through the holes of
the parchment bottom, forming grains of different sizes. The grains
are then sorted and separated from the dust by sieves of progressive
dimensions.

They are then _glazed_ or hardened, and the rough edges taken off,
by being put into casks, filling them somewhat more than half-full,
which are fixed to the axis of a water-wheel, and in thus rapidly
revolving, the grains are shaken against each other and rounded, at
the same time receiving a slight gloss or glazing. Much dust is also
separated by this process. The glazing is found to lessen the force
of the powder from a fifth to a fourth, but the powder keeps much
better when glazed, and is less liable to grow damp.

The powder being thus corned, dusted and glazed, is sent to the
stove-house and dried, a part of the process which requires the
greatest precautions to avoid explosion, which in this state would
be much more dangerous than before the intimate mixture of the
ingredients.

The stove-house is a square apartment, three sides of which are
furnished with shelves or cases, on proper supports, arranged round
the room, and the fourth contains a large cast-iron vessel called a
_gloom_, which projects into the room, and is strongly heated from
the outside, so that it is impossible that any of the fuel should
come in contact with the powder. For greater security against sparks
by accidental friction, the glooms are covered with sheet copper, and
are always cool when the powder is put in or taken out of the room.
Here the grains are thoroughly dried, losing in the process all that
remains of the water added to the mixture in the mill, to bring it to
a working stiffness. This Mr. Coleman finds to be from three to five
parts in 100 of the composition. The powder when dry is then complete.

The government powder for ordnance of all kinds as well as for
small arms, is generally made at one time, and always of the same
composition; the difference being only in the size of the grains as
separated by the respective sieves.

A method of drying powder by means of steam-pipes running round
and crossing the apartment has been tried with success: by it
all possibility of an accident from over-heating is prevented.
The temperature of the room when heated in the common way by a
gloom-stove is always regulated by a thermometer hung in the door of
the stoves.

The strength of the powder is sometimes injured by being dried too
hastily and at too great a heat, for in this case some of the sulphur
sublimes out (which it will do copiously at a less heat than will
inflame the powder) and the intimate mixture of the ingredients is
again destroyed. Besides if dried too hastily, the surface of the
grain hardens leaving the inner part still damp.

Mr. Coleman deduces from experiment the following inferences, namely:
that the ingredients of gunpowder only pulverized and mixed have but
a very small explosive force: that gunpowder granulated after having
been only a short time on the mill, has acquired only a very small
portion of its strength, so that its perfection absolutely depends
on very long-continued and accurate mixture and incorporation of
the ingredients: that the strength of gunpowder does not depend on
granulation, the dust that separates during this process being as
strong as the clean grains: that powder undried, is weaker in every
step of the manufacture than when dried: and lastly, that charcoal
made in iron cylinders in the way already mentioned, makes much
stronger powder than common charcoal. This last circumstance is of so
much consequence, and is so fully confirmed by experience, that the
charges of powder now used for cannon of all kinds have been reduced
one-third in quantity, when this kind of powder is employed.

In barrelling powder, particular care must be taken to avoid
moisture, and this business is also generally reserved for dry
weather.

When powder is only a little damp, it may be restored to its former
goodness merely by stoving; but if it has been thoroughly wetted,
the nitre (the only one of the ingredients soluble in water)
separates more or less from the sulphur and charcoal, and by again
crystallizing, cakes together the powder in whitish masses, which
are a loose aggregate of grains covered on the surface with minute
efflorescences of nitre. In this case the spoiled powder is put into
warm water merely to extract the nitre, and the other two ingredients
are separated by straining and thrown away.

The specific gravity of gunpowder is estimated by Count Rumford to be
about 1.868.

The strength and goodness of powder is judged of in several ways;
namely, by the colour and feel, by the flame when a small pinch
is fired, and by measuring the actual projectile force by the
_eprouvette_, and by the distance to which a given weight will
project a ball of given dimensions under circumstances in all cases
exactly similar.

When powder rubbed between the fingers easily breaks down into an
impalpable dust, it is a mark of containing too much charcoal, and
the same if it readily soils white paper when gently drawn over it.
The colour should not be absolutely black, but is preferred to be
more of a dark blue with a little cast of red. The trial by firing is
thus managed; lay two or three small heaps of about a dram each on
clean writing paper, about three or four inches asunder, and fire one
of them by a red-hot iron wire: if the flame ascends quickly with a
good report, sending up a ring of white smoke, leaving the paper free
from white specks and not burnt into holes, and if no sparks fly off
from it, setting fire to the contiguous heaps, the powder is judged
to be very good, but if otherwise, either the ingredients are badly
mixed, or impure.

Gunpowder mixed with powdered glass, and struck with a hammer is said
to explode.

An advertisement appeared in the public papers some time in 1813
or 14, signed T. Ewel, addressed to powder manufacturers, by which
it appears, in the words of the advertisement, that "he obtained
from the United States a patent right for three very simple and
important improvements in the manufacture of gunpowder, which do
most truly diminish more than one half the risk, the waste, and the
expense of the manufacture. They consist in boiling the ingredients
by steam, in incorporating them without the objection of barrels,
the danger of pounders, or the tediousness of stones running on the
edge: and in the granulation effected by a simple machine turning
by hand or water, and graining more in a day than twenty hands,
losing not a particle of dust, and making not half the quantity for
re-manufacture. The advantages of this mode have been so great that
he had to discharge half his workmen from his manufactory, as will
be readily accounted for by those accustomed to the tediousness and
loss from graining, particularly the press powder by the sifter and
rollers, &c."

We have not seen the plan in operation, and, therefore, can say
nothing respecting it; but it would appear, from the description,
that the process was conducted altogether by steam. It is true, that
the use of steam is no new application, nor was it then, as it had
been used in Europe for heating of dye kettles, in soap boiling,
distilling, for warming apartments, and many other purposes. The
application to that particular use, that of the manufacture of
gunpowder, may be original as far as we know, notwithstanding steam
has been applied by means of pipes, &c. as is used at present in
some manufactories, for the drying of gunpowder. Professor, now
president Cooper, of Columbia College, S. C. (_Emporium of Arts and
Sciences_ vol. ii, p. 317) in making some observations respecting
that publication, believes, that the application of steam to the
manufacture of gunpowder to be practicable, and in reference to the
advertisement, also a real improvement; and speaking of steam for
that purpose adds, "whether it be adopted in England or not, or
whether among the numerous patents granted for the application of
steam to the arts and manufactures of that country, I know not."

On a general principle of heating apartments by steam, we may
remark, that one _cubic foot_ of boiler will heat about _two
thousand feet_ of space, in a cotton mill, whose average heat is
from 70° to 80° Fahr. One square foot of surface of steam pipe, is
adequate to the warming of two hundred cubic feet of space. Cast
iron pipes are preferable to all others for the diffusion of heat.
For drying muslins and calicoes, large cylinders are employed, and
the temperature of the apartment is from 100° to 130°. Dr. Black
observes that steam is the most effectual carrier of heat that can
be conceived, and will deposite it only on such bodies as are colder
than boiling water.

Dr. Ure (_Researches on Heat_) has given a new table of the latent
heat of vapours, by which it appears that the vapour of water, at its
boiling point, contains 1000 degrees, while that of alcohol of the
specific gravity, .825 contains 457°, and ether, whose boiling point
is 112°, only 312.9. We see then not only by the recent experiments
of Ure, but also those of Dr. Black, Lavoisier and Laplace, Count
Rumford, Mr. Watt and some others, that water is the best carrier
of heat, using the expression of Dr. Black, and hence is admirably
calculated for the warming of apartments and other purposes.

Steam may be applied for the heating of water or other fluids, either
for baths or manufactures, and consequently for the saltpetre and
sulphur refineries, attached to a gunpowder establishment, either by
plunging the steam pipe with an open end into the water cistern, if
it be for the heating of water, or by diffusing it around the liquid
in the interval between the wooden vessel and an interior metallic
case. This last mode is applicable to all purposes.

A gallon of water in the form of steam will heat 6 gallons at 50° up
to the boiling point, or 162 degrees; or one gallon will be adequate
to heat 18 gallons of the latter up to 100 degrees, making an
allowance for waste in the conducting pipe.

Mr. Woolf (_Monthly Magazine_ vol. xxxii, p. 253) has taken out a
patent for a steam apparatus for various purposes, among which that
for the drying of gunpowder is specified. This patent is considered
under three heads; _viz._ the construction of the boilers, which are
cylindrical vessels properly connected together, and so disposed as
to constitute a strong and fit receptacle for water, or any other
fluid, intended to be converted into steam, and also to present an
extensive portion of convex surface to the current of flame, or
heated air or vapour from a fire. Secondly, of other cylindrical
receptacles placed above these cylinders, and properly connected
with them, for the purpose of containing water and steam, and for
its reception, transmission, &c. Thirdly, of a furnace so adapted to
the cylindrical parts just mentioned, as to communicate heat with
facility and economy. By means of this invention, he states, that any
desired temperature, necessary for the drying of gunpowder, may be
produced where the powder is to be dried, without the necessity of
having fire in, or so near the place as to endanger its safety; for
by employing steam only, conveyed through pipes, and properly applied
and directed, without allowing any of it to escape into the room or
apartment where the powder is, any competent workman can produce a
heat equal to that found necessary for drying gunpowder, or much
higher if required. The heat may be regulated, to effect the purpose,
without producing the sublimation of the sulphur, which has sometimes
taken place.

Among the numerous patents of the late D. Pettibone are some for
ovens, both fixed and portable, for the drying of gunpowder. Speaking
of the use of heated air (_Description of the Improvements of the
Rarefying air-stove_, p. 19) he observes, that powder makers would
derive a very great advantage by using rarefied air for drying their
gunpowder.

Mr. Ingenhouz (_Nouvelles experiences et observations sur divers
objects de physique_) attributed the effect of gunpowder to the
simultaneous disengagement of dephlogisticated air from the nitre,
and inflammable air from the charcoal at the moment of ignition. He
followed the calculation of Bernouilli with respect to the quantity
of gas generated, _viz_: that one cubic inch of gunpowder at the
moment of inflammation, calculating at the same time its expansion,
occupies not less than 2276 cubic inches.

That the effective force of gunpowder depends on the generation and
expansion of sundry gaseous fluids, is evident, from the chemical
action which takes place in the combustion. At a _red_ heat gunpowder
explodes. This ensues even in a vacuum; a fact at once conclusive,
that, while it possesses the inflammable principle, it has also the
supporter of combustion. It is to be observed that the particle of
powder which is struck by the spark, is instantaneously heated to the
temperature of ignition, and is thereby decomposed; and the affinity
existing between its oxygen or the oxygen of the nitric acid, and the
charcoal and sulphur produces the principal part of the gases. The
caloric thus evolved, inflames successively, though with rapidity,
the remaining mass. The expansive force of powder, is therefore
attributed to the sudden production of carbonic acid gas, sulphurous
acid and nitrogen gas, with the water which is instantaneously
converted into steam; all of which are greatly augmented by the
quantity of caloric liberated.

The combustion, therefore, is owing to the action of the charcoal
and sulphur on the nitre; and the decomposition is the effect of
the union of the charcoal with a part of the oxygen of the nitric
acid, with which it forms carbonic acid, and also with the sulphur
producing sulphurous acid gas. It is asserted, that sulphuretted
hydrogen gas is also produced; if so, there must be a sulphuret
formed, which decomposes a part of the water. After combustion, what
remains is carbonate of potassa, sulphate of potassa, and a small
proportion of sulphuret of potassa and unconsumed charcoal. Good
powder, however, should leave no very sensible residue when inflamed:
this is one of the proofs recommended. Thenard observes, (_Traité
de Chimie_, ii, p. 498,) that the products of the combustion of
gunpowder are numerous; some gaseous, and some solid. The gaseous
products are carbonic acid, deutoxide of azote (nitrous gas) and
azotic gas, besides the vapour of water; and the solid products are
sub-carbonate of potassa, sulphate of potassa, and sulphuret of
potassa.

M. Proust considers, that nitrite of potassa, prussiate of potassa,
charcoal, sulphuretted hydrogen gas, carburetted hydrogen gas,
nitrous gas, and carbonic oxide gas may be generated or result, as
the products of the combustion, when the materials have not been
properly mixed. Our object in all cases should be to render the
materials pure, and the proportions so accurate, as to produce the
greatest possible effect, which, of course, must depend on the
formation and the consequent expansion of the gases. The effect of
fired gunpowder is owing in a great degree to the generation of
carbonic acid gas; for while the charcoal acts primarily in the
combustion, by taking a greater part of the oxygen from the nitric
acid of the nitre, with which we have said it produces carbonic
acid; the sulphur has a secondary influence, by forming sulphurous
acid gas, although it renders the combustion more rapid, and in this
respect enables the charcoal to act at once on the nitric acid of the
saltpetre.

We learn then, that in gunpowder, the quantity of charcoal should
be such as to effect the decomposition; and, that while the sulphur
has a secondary effect, in the formation of sulphurous acid gas,
it promotes, if so we may term it, the _rapid_ combustion, and
consequent action of the charcoal.

MM. Bottée and Riffault (_Traité de l'art de Fabriqué la poudre à
canon, p. 197_,) after making some observations on the constitution
of powder, and the action which takes place when it is burnt,
with the aeriform products that result, give some remarks on the
proportion of charcoal necessary to decompose a given quantity of
nitric acid; and conclude generally, that in the production of
carbonic acid gas, the principal gas which is formed, while the
nitric acid is decomposed, and gives up its oxygen to the carbon,
the azote is liberated in the state of gas, and at the same time
caloric is evolved. They observe then, that the ancient formula
for the manufacture of gunpowder, as used in France, consists of
the following proportions, _viz_: 0.750 saltpetre, 0.125 charcoal,
and 0.125 sulphur, which agrees with modern experiments, although
chemistry at that period was in its infancy. M. Pelletier, a member
of the National Institute, and M. Riffault made several experiments
at Essonne, on different proportions of nitre, charcoal, and
sulphur in the fabrication of powder. It is unnecessary to state
the different proportions, made use of, or the experiments on the
strength of the powder made with the eprouvette. They observe,
however, that powder made in the following proportions, was more
satisfactory, _viz._ 0.76 saltpetre, 0.15 charcoal, 0.09 sulphur, and
0.76 saltpetre, 0.14 charcoal, and 0.10 sulphur.

Before we give the gaseous products, according to these gentlemen,
it will be necessary to observe, that the quantity of nitric acid
in nitrate of potassa, is 48.62 in the hundred, and according to
Gay-Lussac, nitric acid is composed in volume of 250 oxygen and 100
azote, or in weight of 69.488 oxygen, and 30.512 azote.

Using the French _gramme_ in the present instance, it appears that
75 grammes of nitrate of potassa, the proportion of this salt which
enters into 100 grammes of gunpowder for war, contains 36.47 grammes
of nitric acid; and that this quantity of acid is formed of 25.34
grammes of oxygen, and 11.13 grammes of azote. That quantity of
oxygen (25.34) is disengaged from its combination with azote in the
nitric acid, at the instant of the inflammation of the powder by the
charcoal, forming carbonic acid; the constituents of which, according
to the proportions established by Gay-Lussac and others, must be in
the ratio of 27.376 of carbon and 72.624 of oxygen. If 25.34 grammes
of oxygen exist in 75 grammes of nitrate of potassa, the proportion
usually admitted, then it will require 9.55 grammes of carbon to
saturate it, so as to produce carbonic acid. It is necessary to
consider, that this is independent of any foreign earthy or saline
matter or moisture which may exist.

With respect to the presence of hydrogen in charcoal, the
observations of Dr. Priestley, Cruikshanks, Kirwan, Berthollet,
Gay-Lussac, Thenard, Vauquelin, Lowitz and some others, are
conclusive on that head. Lavoisier made the quantity of hydrogen in
charcoal upon an average, to be 0.125 of its weight. See _Memoirs de
la Société d'Arcueil_, tome ii, p. 343, and the _Statique Chimique_,
tome ii, pages 44 and 45, and also _charcoal_ in a preceding section.

It is said, that by employing more charcoal than is necessary to
decompose the nitric acid of the nitre, the excess passes off, not
as carbonic acid, but carbonic oxide, or gaseous oxide of carbon,
which is necessarily inflamed, and finally forms carbonic acid, as
one of the products with the carbonic acid originally formed. But the
carbonic oxide, to be changed into carbonic acid, requires in fact
the oxygen of the atmosphere.

If 34.89 grammes of carbonic acid result from the combustion of
9.55 grammes of carbon, it must unite with a quantity of oxygen,
as before expressed, and according to the temperature, be more or
less expanded. The 11.13 grammes of azote thus disengaged from its
combination with oxygen, in the nitric acid, remains, of course, in
the gaseous state, and is also expanded by caloric. The quantity of
the latter is stated by Lavoisier, to be 430 degrees, using a scale
of 80 parts; and according to more recent experiments, it is fixed
at 600 degrees of the centigrade thermometer. The experiments of
Gay-Lussac are more recent, in which he has given the dilatation
of the gases, and the quantity of free caloric evolved, which
corresponds with the last data. We have not room to insert his
remarks.

The use of sulphur with the charcoal, in the fabrication of powder,
Bottée and Riffault state to be, (page 204) that it inflames more
rapidly than charcoal, and at a lower temperature, which accelerates
the combustion of the charcoal, and consequently the detonation of
the powder. The presence of the sulphur augments the volume of gas,
by producing sulphurous acid gas. The proportion of sulphur in the
powder for war, is, 0.125, for musket powder, 0.10, and for mining
powder, 0.20, according to the same gentlemen.

M. Fourcroy (_Système des Connaissances Chimiques_, tome iii, p.
122.) among other products of the combustion of powder, mentions
ammonia. If ammoniacal gas be formed, the hydrogen must proceed from
decomposed water, and the azote from the nitric acid. Prussine,
cyanogen, or carburet of nitrogen, the radical of prussic acid, may
also be generated by the union of carbon and nitrogen or azote, in
the same manner. We know that cyanogen may exist in the form of gas;
but as it is inflammable, burning with a bluish flame mixed with
purple, we may infer, nevertheless, that, if generated, it must
undergo decomposition by the process of combustion. Although I know
of no experiments on this subject, either by Gay-Lussac, Vauquelin or
Davy, all of whom have investigated the properties of this compound
of carbon and azote, which Dr. Ure has called _prussine_; yet it
would appear, that during its combustion, the carbon is changed into
carbonic acid, and whether the azote be also combined with oxygen,
or merely set at liberty, is altogether uncertain. Many difficulties
present themselves to a complete and satisfactory set of experiments
on the gaseous products of fired gunpowder.

With respect to the granulation of powder, we may observe, that
although some writers consider that granulated powder is _stronger_
than the fine powder, yet others are of opinion, that its strength is
not increased by granulation. Grained powder is more fit for use; but
the graining of it prevents the whole of the powder from taking fire
instantaneously. Gunpowder, although prepared in the best manner,
is not wholly consumed by inflammation. However remarkable it may
appear, yet nevertheless it is true, that a considerable portion
of gunpowder fired in a confined space is thrown out without being
kindled. That gunpowder passes through a volume of fire without being
consumed, may seem incredible, yet the fact may be proved by firing
with a musket upon snow, or upon a paper screen.

M. Morveau communicated to the Institute some experiments, which may
be seen in the _Archives des Découvertes_, i, p. 269, relative to the
time necessary for the inflammation of a given mass of gunpowder, &c.
He infers that large grain powder inflames more readily than the fine
grain.

Since during the combustion of powder, gaseous bodies more or less
considerable are generated, it follows that the full force of fired
gunpowder must depend on the maximum of the quantity of those gases;
and the powder is more strong as it is susceptible of forming more
gas in a given time. Besides the purity and the proper proportion
of the materials, the gunpowder, to produce the greatest possible
effect, should not only be intimately mixed, but dried perfectly and
with care.

It is a fact which is well known, that a musket, fowling piece, &c.
are very apt to burst, if the wadding is not rammed down close to the
powder. Hence it is obvious, that in loading a screw barrel pistol,
care should be taken that the cavity for the powder be entirely
filled with it, so as to leave no space between the powder and the
ball.

Experience has shown, that if a shell is only half or two-thirds
filled with gunpowder, it breaks into a great number of pieces, and
on the contrary, if completely filled, it separates only into two or
three pieces, which are thrown to a very great distance.

It is also found that the same principle, of leaving a space for
air, is applied with success in blasting rocks, and splitting trunks
of trees. If the trunk of a tree is charged with gunpowder, and
the wadding is rammed down very hard upon the powder, in that case
(unless the quantity of powder is great,) the wadding is only driven
out, and the tree remains entire; but if, instead of ramming the
wad close to the powder, a certain space is left between them, the
effects of the powder are then such as to tear the tree asunder.

Addison (_Travels through Italy and Swisserland_) speaking of the
celebrated Grotto Del Cani, which contains carbonic acid gas, and
on that account extinguishes flame, and is fatal to animal life,
observes, that he laid a train of gunpowder in the channel of a reed,
and placed it at the bottom of the grotto, and on inflaming it, that
it burnt entirely away, although the carbonic acid gas in the same
spot would immediately extinguish a lighted taper, snuff and all;
for, he remarks, fire is as soon extinguished in it as in water. If
gunpowder did not contain within itself that which was necessary to
produce combustion, how are we to account for its combustion in an
atmosphere of carbonic acid gas, or in vacuo?

Whether gunpowder be fired in a vacuum or in air, a permanently
elastic fluid is generated, the elasticity or pressure of which is,
_cæteris paribus_, directly as its density.

Gregory, (_Treatise on Mechanics, &c._ ii, p. 56) has given a summary
of the results of the experiments of Mr. Robins, which we insert
verbatim. "To determine the elasticity and quantity of this fluid
(the elastic) produced from the explosion of a given quantity of
gunpowder, Mr. Robins premises, that the elasticity increases by
heat, and diminishes by cold, in the same manner as that of the air;
and that the density of this fluid, and consequently its weight, is
the same with an equal bulk of air, having the same elasticity at the
same temperature. From these principles, and from the experiments by
which they are established (for a detail of which we must refer to
the book itself,) he concludes that the fluid produced by the firing
of gunpowder, is nearly 3/10ths of the weight of the generating
powder itself; and that the volume or bulk of this air or fluid, when
expanded to the rarity of common atmospheric air, is about 244 times
the bulk of the said generating powder. Count Salace in his _Miscel.
Phil. Math. Soc. Priv._ Taurin, p. 125, makes the proportion as 222
to 1; which he says agrees with the computation of Messrs. Hawkesbe
Amontons, and Belidor. Hence it would follow that any quantity of
powder fired in any confined space, which it adequately fills, exerts
at the instant of its explosion against the sides of the vessel
containing it, and the bodies it impels before it, a force at least
244 times greater than the elasticity of common air, or, which is the
same thing, than the pressure of the atmosphere; and this without
considering the great addition arising from the violent degree of
heat, with which it is endued at that time; the quantity of which
augmentation is the next head of Robins's inquiry.

He determines that the elasticity of air is augmented in a proportion
somewhat greater than that of 4 to 1, when heated to the extremest
heat of red-hot iron; and supposing that the flame of fired gunpowder
is not of a less degree of heat, increasing the former number a
little more than four times, makes nearly 1000; which shows that the
elasticity of flame, at the moment of explosion, is about 1000 times
stronger than the elasticity of common air, or than the pressure of
the atmosphere. But, from the height of the barometer, it is known
that the pressure of the atmosphere upon every square inch is on a
medium of 14-3/4ths, and therefore 1000 times this, or 14750 lbs.
is the force of pressure of inflamed gunpowder, at the moment of
explosion, upon a square inch, which is very nearly equivalent to six
tons and a half. This great force, however, diminishes as the fluid
dilates itself, and in that proportion; viz. in proportion to the
space it occupies, it being only half the strength, when it occupies
a double space, one-third the strength, when a triple space, and so
on. Mr. Robins further supposed the degree of heat above mentioned to
be a kind of medium heat; but that in the case of large quantities of
powder the heat will be higher, and in very small quantities lower;
and that therefore in the former case the force will be somewhat
more, and the latter somewhat less, than 1000 times the force of the
atmosphere.

He further found, that the strength of powder is the same in all
variations in the density of the atmosphere: but that the moisture of
the air has a great effect upon it; for the same quantity which in a
dry season would discharge a bullet with the velocity of 1700 feet in
one second, will not in damp weather give it a velocity of more than
12 or 1300 feet in a second, or even less, if the powder be bad, or
negligently kept. _Robins's Tracts_ vol. i, p. 101, &c. Further, as
there is a certain quantity of water, which, when mixed with powder,
will prevent its firing at all, it cannot be doubted but every degree
of moisture must abate the violence of the explosion; and hence the
effects of damp powder are not difficult to account for.

The velocity of expansion of the flame of gunpowder, when fired in a
piece of artillery, without either bullet or other body before it, is
prodigiously great, viz. 7000 feet per second. But Mr. Bernoulli and
Mr. Euler think it is still much greater.

Dr. Hutton, after applying some requisite corrections to Mr. Robins's
numbers, and after remarking that the powder does not all inflame at
once, as well as that about 7/10ths of it consist of gross matter
not convertible into an elastic fluid, gives v = 125 [sqrt] ((n ·
q)/(16 + q) × log. of b/a) for the initial velocity of any ball of
given weight and magnitude, and n = ((p + w)/3180 ad^2)v^2 ÷ log. b/a
for the value of the initial force n of the powder in atmospheric
pressures: when a = length of the bore occupied by this charge,
b = whole length of the bore, d = diameter of the ball, w = its
weight, 2 p = weight of the powder, q = a/d. In his experiments and
results, he found n to vary between 1700 and 2300, and the velocity
of the flame to vary between 3000 and 4732; specifying, however, the
modification in his computations, which would give more than 7000
feet per second for that velocity. Taking 2200 for an average value
of n, and substituting 47 for its square root in the above formula
for v, it becomes v = 5875 [sqrt] (q/(16 + q) × log. of b/a) for the
velocity of the ball, a theorem which agrees remarkably well with
the Doctor's numerous and valuable experiments. (Tracts, vol. iii, p.
290, 315.)

In a French work entitled, "_Le Mouvement Igné_ considéré
principalement dans la charge d'une pièce d'artillerie," published
in 1809, there are advanced, among other notions which we apprehend
few philosophers will be inclined to adopt, some which may demand
and deserve a careful consideration. The author of this work
observes, that if a fluid draws its force partly from a gaseous
or aeriform matter, and partly from the action of caloric, which
rarefies that aeriform matter; then its density in proportion to its
dilatation, will follow the inverse ratios of the squares of the
spaces described. He then investigates two classes of formulæ: the
first appertains to fluids which possess simply the fluid or aeriform
elasticity, which are free from all heat exceeding the temperature
of the atmosphere. Whether there be one or many gaseous substances
signifies not, provided their temperature agrees with that of the
atmosphere; for when these dilate they conform to the inverse of
the spaces described. The second relate to those which derive their
elasticity as well from the aeriform fluids, as from the matter of
heat which pervades them, and which are denominated _fluids of mixed
elasticity_, to distinguish them from those of simple or purely
_aeriform elasticity_. These fluids, in dilating, conform to the
inverse ratio of the _squares_ of the spaces described. Thus the
celerity of action of mixed elastic fluids, is to that of simple
elastic fluids as S^2 to S; whence it follows that mixed elastic
fluids are more prompt and energetic in their action than others; and
hence also is inferred why the fluid produced by the combustion of
gunpowder, is more impetuous and more terrible in its operation than
atmospheric air, however compressed it may be. The force exerted by
the caloric to dissolve a quantity of powder, is regarded as equal
to that possessed by the fluid which results from that dissolution,
and is named the _force of dissolution_ of powder by fire: and the
_surface of least resistance_ is that (as of the ball,) which yields
to the action of the fluid. The gunpowder subjected to experiment by
this author, was of seven different qualities, varying from 1000,
the density of water, down to 946, the density of powder used by
sportsmen. It was found by theory, and confirmed by experiment, that
the real velocity with which the elastic fluid, considered under the
volume of the powder, and penetrated by a degree of heat capable of
quadrupling the volume, would expand, when it had only the resistance
of the atmosphere to surmount, is 2546.49 feet, that is, about 2734.4
feet English.

Comparing the several forces which were calculated for the same
quantity of powder, in three different circumstances:

1. When the fluid has only to surmount the atmospheric pressure,
it has a force of dissolution which is proper to it, and which in
a charge of 8 lbs. of powder (the specific gravity 944.72, for a
24 pounder,) acts upon the surface of the least resistance with an
energy equivalent to 9747.8074 lbs.

2. The fluid retarded in its expansion by a surface of least
resistance, whose tenacity (occasioned by the compactness and
pressure of the wadding, &c.) is t = 31, acquires by its elasticity
of force = 52839.1463 lbs. at the instant when that surface yields to
its action.

3. If the tenacity t = 298 lbs., the force of the fluid at the moment
when the resisting surface yields to it, will be equivalent to
417371.4275 lbs. If each of these forces be divided by the surface
of least resistance, the quotient will indicate the equation of each
filament, namely, 1st. That of the force of dissolution = 173.63
grains; 2d. when t = 31 lbs. that of elasticity = 923.26 grains; 3d.
when t = 298 lbs. force elastic equal to 7433.99 grains.

Dividing again these latter values by the length of the charges, we
shall have for the mean force of each elementary fluid particle,

1. Force of dissolution, 0.14205 grains.

2. When t = 31 lbs. the force elastic = 0.75540 grains.

3. When t = 298 lbs. the force elastic = 6.08174 grains.

It appears, however, that equal charges of powder of the same quality
employed in the same piece, produce very different velocities; the
more considerable being the resistance to the expansion of the fluid,
the less the velocity becomes. Thus, it is found, when t = 31 lbs.
the velocity of the ball when expelled at the mouth of the piece, is
1563.6 feet: when t = 298 lbs. v = 1350.9 feet.

The following table will exhibit in one view the velocities with
which a 24 lb. ball issues from the mouth of a gun, when propelled
with the several charges expressed in the first column.

1st. According to the theory developed in the volume, from which we
have made these extracts.

2d. According to the experiments of M. Lombard, at Auxerre, on guns
for land service.

3d. According to the experiments of M. Teixiere de Norbec, at Toulon,
on guns for sea service.

4th and 5thly. According to the determination of Mr. Robins and Dr.
Hutton.

+-------+---------------+--------+-----------------+-----------------+
| | Velocity from | Mean | Velocity from | VELOCITIES. |
|Charges| Theory |velocity| experiment. | |
| of +-------+-------+ from +- ------+--------+--------+--------+
|powder.| When | When | Theory.| | | | |
| | t=31. | t=298.| |Lombard.|Norbec. |Robins. |Hutton. |
+-------+------ +-------+--------+--------+--------+--------+--------+
| 1 lb. | 622 | 524 | 573 | 575 | 570 | 640 | 500 |
| 2½ | 980 | 836 | 908 | 906 | 940 | 750 | 730 |
| 3 | 1072 | 918 | 995 | 989 | 1020 | 969 | 830 |
| 4 | 1233 | 1057 | 1145 | 1132 | 1245 | 1069 | 940 |
| 6 | 1407 | 1216 | 1312 | 1320 | 1340 | 1215 | 1164 |
| 8 | 1564 | 1351 | 1457 | 1425 | 1560 | 1319 | 1348 |
|10 | 1581 | 1370 | 1476 | 1475 | | | 1500 |
|12 | 1631 | 1421 | 1526 | 1530 | | | 1600 |
+-------+-------+-------+--------+--------+--------+--------+--------+

It is the prodigious celerity of expansion of the flame of fired
gunpowder, which is its peculiar excellence, and the circumstance in
which it so eminently surpasses all other inventions, either ancient
or modern; for as to the momentum of these projectiles only, many of
the warlike machines of the ancients produced this in a degree far
surpassing that of our heaviest cannon, shot or shells; but the great
celerity given to them cannot be approached with facility by any
other means than the explosion of powder."

Dr. Hutton, in conjunction with several able officers of the
artillery and other gentlemen, made an extensive course of
experiments at Woolwich, at the expense of the British government,
by the direction of the then master-general of the ordnance, (the
late duke of Richmond,) in the years 1783, 1784, and 1785, which
demonstrated the following facts:

1. That the velocity continually increases as the gun is longer,
though the increase in velocity is but very small in respect of
the increase in length; the velocities being in a ratio somewhat
less than that of the square roots of the length of the bores, but
somewhat greater than the cube roots of the same, and nearly indeed
in the middle ratio between the two.

2. That the charge being the same, very little is gained in the
range of a gun, by a great increase of its length; since the range
or amplitude is nearly as the fifth root of the length of the bore,
and gives only about a seventh part more range with a gun of double
length.

3. That with the same gun and elevation, the time of the ball's
flight is nearly as the range.

4. That no sensible difference is produced in the range or velocity,
by varying the weight of the gun, by the use of wads, by different
degrees of ramming, or by firing the charge of powder in different
parts of it.

5. That a great difference, however, in the velocity, is occasioned
by a small variation in the windage; so much so, indeed, that with
the usual windage of one-twentieth of the caliber, no less than
between one-third and one-fourth of the whole charge of the powder
escapes and is entirely lost; and that as the windage is often
greater, one-half the powder is unnecessarily lost.

6. That the resisting force of wood to balls fired into it, is not
constant, and that the depths penetrated by different velocities, or
charges, are not as the charges themselves, or, which comes to the
same thing, as the squares of the velocities.

7. That balls are greatly deflected from the direction they are
projected in, sometimes, indeed, so much as 300 or 400 yards in a
range of a mile, or almost a fourth part of the whole range, which is
nearly a deflection of an angle of 15 degrees.

The observations of Glenie, (_History of Gunnery_, 1776,) show the
theory of projectiles in vacuo by plain geometry, or by means of the
square and rhombus; with a method of reducing projections on inclined
planes, whether elevated or depressed below the horizontal plane, to
those which are made on the horizon.

This author, in his treatise, after stating in page 48, the two
following positions of Mr. Robins, namely, "that till the velocity of
the projectile surpasses that of 118 feet in a second; the resistance
of the air may be estimated to be in the duplicate of the velocity;"
that "if the velocity be greater than that of 11 or 1200 feet in a
second, the absolute quantity of the resistance will be nearly three
times as great as it should be by a comparison with the smaller
velocities;" says, that he is certain from some experiments, which he
and two other gentlemen tried with a rifle piece properly fitted for
experimental purposes, that the resistance of the air to a velocity
somewhat less than that mentioned in the first of these proportions,
is considerably greater than in the duplicate ratio of the velocity;
and that to a celerity somewhat greater than that stated in the
second, the resistance is less than that which is treble the
resistance of the same ratio. He observes, also, that some of Mr.
Robins's own experiments come to this conclusion; since to a velocity
no quicker than 200 feet in a second, he found the resistance to
be somewhat greater than in that ratio, and remarks, therefore,
that "after ascertaining the velocities of the bullets with as much
accuracy as possible, I instituted a calculus from principles which
had been laying by me for some time before, and found the resistance
to approach nearer to that, which exceeds the resistance in the
duplicate ratio of the velocity, by that which is the ratio of the
velocity, than to that, which is only in the duplicate ratio."

The experiments of Mr. Dalton, confirm the premises of Mr. Robins,
that the elasticity of the gases produced from a given quantity
of powder, is equally increased by heat and diminished by cold as
that of atmospheric air. Hence, as we before remarked, and from
direct experiments, he concludes that the elastic fluid produced by
the firing of gunpowder, is nearly three-tenths of the weight of
the powder itself, which, expanded to the rarity of common air, is
about 244 greater than the elasticity of common air, or in other
words, than the pressure of the atmosphere. To this, however, must
be superadded the increase of expansive power produced by the heat
generated, which is very intense. The mere conversion of confined
powder into elastic vapour, would exert against the sides of the
containing vessel, an expansive force 244 times greater than the
elasticity of common air, or, in other words, than the pressure of
the atmosphere. If the heat, for the expansion of the gases, should
be equal to that of red-hot iron, this would increase the expansion
of common air, (and also of all gases) about four times, which in
the present instance would be as we stated in the preceding pages,
244 to nearly 1000; so that in a general way it may be assumed, that
the expansive force of closely confined powder at the instant of
firing, is 1000 times greater than the pressure of common air; and
as this latter is known to press with the weight of 14-3/4 pounds on
every square inch, the force of explosion of gunpowder is 1000 times
this, or 14750 lbs. or about six tons and a half upon every square
inch. This enormous force diminishes in proportion as the elastic
fluid dilates, being only half the strength when it occupies a double
space, one-third of the strength when in a triple space, and so on.

There is one more fact worthy of notice, that Mr. Robins found the
strength of powder to be the same in all variations of the density
of the atmosphere, but not so in every state of moisture, being much
impaired by a damp air, or with powder damped by careless keeping,
or any other cause; so that the same powder which will discharge a
bullet at the rate of 1700 feet in a second in dry air, will only
propel it about 1200 feet when the air is fully moist, and a similar
difference was observed between dry and moist powder. The sum of
these remarks, with the necessary illustrations, may be found in the
extract we have given from Gregory's Mechanics.

Before we mention the different modes of proving powder, we will
offer some remarks respecting the use of sulphur in gunpowder. The
conclusions on this head are drawn from the experiments made at
Essonne, near Paris.

The sulphur is not (properly speaking) a necessary ingredient
in gunpowder, since nitre and charcoal alone, well mixed, will
explode; but the use of the sulphur seems to be to diffuse the
fire instantaneously through the whole mass of powder. But, if the
following experiments are correct, it should seem that the advantage
gained by using sulphur in increasing the force of explosion only
applies to small charges; but in quantities of a few ounces, the
explosive, or at least the _projecting_ force of powder without
sulphur, is full as great as with sulphur.

The following are a few out of many trials made at the Royal
Manufactory at Essonne, near Paris, in the year 1756, to determine
the best proportions of all the ingredients. Of powder made with
nitre and charcoal alone, 16 of nitre and 4 of charcoal was the
strongest, and gave a power of 9 in the eprouvette. With all three
ingredients, 16 of nitre, 4 of charcoal, and 1 of sulphur, raised the
eprouvette to 15, and both a less and a greater quantity of sulphur
produced a smaller effect. Then diminishing the charcoal, a powder
of 16 of nitre, 3 of charcoal, and 1 of sulphur gave a power of 17
in the eprouvette, which was the highest produced by any mixture.
This last was also tried in the mortar-eprouvette against the common
proof powder, and was found to maintain a small superiority. The
powder made without sulphur in the proportions above indicated was
also tried in the mortar-eprouvette, and with the following singular
result: when the charge was only two ounces it projected a sixty
pound copper ball 213 feet, and the strongest powder with sulphur
projected it 249 feet; but in a charge of three ounces, the former
projected the ball 475 feet and the latter only 472 feet; and on the
other hand the great inferiority of force in the smaller eprouvette
of the powder without sulphur has been just noticed.

It is a fact, known from time immemorial, that by the combustion of
bodies caloric is generated, or chemically speaking, is given out in
a free state; but the cause was not known until the anti-phlogistic
theory of chemistry was established, which abolished as untenable
the old doctrine of phlogiston; The quantity of caloric, which
passes from a latent to a free state in combustion, as combustion
is nothing more than the phenomena occasioned by this transition,
is variable; and depends therefore on the substances burnt, and the
nature of what is denominated the supporter of combustion.

The experiments of MM. Lavoisier and Laplace have shown the quantity
of caloric produced by the combustion of different substances by
the calorimeter, a table of which may be seen in Thenard. (_Traité
de Chimie_, &c. t. i, p. 81). From this table it appears, that
while a mixture of one pound of saltpetre with one pound of sulphur
liquefied, by its combustion, thirty-two pounds of ice, one pound
of hydrogen gas melted 313 lbs. phosphorus 100 lbs. and the same
quantity of charcoal 96.351 lbs.; and by the detonation of a mixture
of one pound of saltpetre with 0.3125 lbs. of charcoal (French
weight) melted only 12 lbs. of ice.

In the table of the elevation of temperature by the combustion of
different substances, the caloric being communicated to water,
(Thenard, _Traité de Chimie_, vol. i, p. 82), it appears, that by the
combustion of equal weights of hydrogen gas, phosphorus, charcoal,
and oak, the caloric produced was as follows:

Hydrogen 23,400°
Phosphorus 7,500
Charcoal 7,226
Oak wood 3,146

The reader may find some interesting calculations on this subject in
Biot's _Traité de Physique_, &c. tome iv, p. 704, and 716.

It appears also, that in the combustion of one pound of hydrogen
gas, six pounds of oxygen were consumed, and according to Crawford's
experiment the caloric given out melted 480 lbs. of ice. One pound of
phosphorus requires for combustion one and a half pounds of oxygen
gas; one pound of charcoal, 2.8; and one pound of sulphur, 1.36. See
Thomson's _System of Chemistry_, vol i, p. 133.

While noticing this subject we may remark, that in combustion heat
and light, according to the Lavoiserian doctrine, are given out from
the oxygen gas, while the oxygen unites with the combustible body:
which has since been modified by supposing, that while caloric is
evolved from the gas, the light is emitted from the burning body.
There are some facts contrary to the received theory of combustion;
that of _gunpowder_ furnishes one. We have also another instance in
the combustion of oil of turpentine by nitric acid.

Gunpowder will burn with great avidity in close vessels, or under
an exhausted receiver, and we know that the oxygen is already
combined with azote in the nitric acid of the nitrate of potassa,
and consequently not in a gaseous but a solid state; yet we also
know that a great quantity of caloric and light are emitted during
the combustion, and nearly all the products are gaseous. The other
anomaly is, that as combustion is produced by pouring nitric acid on
spirit of turpentine, the oxygen being already combined with azote,
caloric and light are evolved by the mixture of the two fluids,
from which it is inferred, that oxygen is capable of giving out
caloric and light, not only when liquid, but even after combustion.
In the instance of gunpowder, in order to explain the combustion
which takes place independently of atmospheric air, or any aeriform
supporter, "the caloric and light," in the opinion of Dr. Thomson,
(_Chemistry_, i, 128) "must be supposed to be emitted from a solid
body during its conversion into gas, which ought to require more
caloric and light for its existence in the gaseous state than the
solid itself contained."--Mr. Lavoisier (_Elements of Chemistry_, p.
157,) observes, that he and M. De la Place deflagrated a convenient
quantity of nitre and charcoal in an ice apparatus, and found that
12 lbs. of ice were melted by the deflagration of one pound of
nitre. After giving the proportions of acid and alkali in nitre,
and the quantity of oxygen and azote in the acid, he observes, that
during the deflagration, 145-1/3 grains of carbon have suffered
combustion along wit 3738.34 grains of oxygen; and as 12 lbs. of
ice were melted, one pound of oxygen burnt in the same manner would
have melted 29.5832 lbs. of ice. To which, if we add the quantity of
caloric retained by a pound of oxygen, after combining with carbon to
form carbonic acid gas, which was already ascertained to be capable
of melting 29.13844 lbs. of ice, we shall have for the total quantity
of caloric remaining in a pound of oxygen when combined with nitrous
gas in the nitric acid, 58.72164; which is the number of pounds of
ice, the caloric remaining in the oxygen in that state is capable of
melting. In the state of oxygen gas it contains at least 66.66667.
M. Lavoisier infers then, that the oxygen in combining with azote
to form nitric acid, only loses 7.94502, and that "this enormous
quantity of caloric, retained by oxygen in its combination into
nitric acid, explains the cause of the great disengagement of caloric
during the deflagration of nitre; or, more strictly speaking, upon
all occasions of the decomposition of nitric acid." This view of
the subject may enable us to explain the production of caloric, in
those cases of combustion which cannot be explained on the ordinary
principles; and, with regard to gunpowder, the accension of oil of
turpentine by nitric acid, and similar cases, we may conclude, as the
only rationale which seems applicable, that it is nothing more than
the transition of caloric from one state to another, from a latent
to a free state. Be this as it may, the combustion in such instances
furnishes an anomaly to the already established doctrine, of the
absorption of oxygen, or the base of the supporter, and the evolution
of caloric from the gas, and not from the combustible; or, in other
words, the change of caloric in the supporter from a combined to an
uncombined state.

The idea of _latent_ heat may be had from Dr. Black's own expression
(_Black's Lectures_ by Robinson:) "By this discovery," says
the doctor, "we now see heat susceptible of fixation--of being
accumulated in bodies, and, as it were, laid by till we have occasion
for it; and are as certain of getting the stored-up heat, as we are
certain of getting out of our drawers the things we laid up in them."
Murray's _System of Chemistry_, 2d edition, p. 398, and Watson's
_Chemical Essays_, vol. iii, &c. may be consulted on this subject
with advantage. See _Introduction_.

We will consider, in the next place, the subject of _gunpowder
proof_. The first examination of gunpowder is by rubbing it in the
hands, to find whether it contains any irregular hard lumps. If it
is too black, it is a sign that it is moist, or else, that it has
too much charcoal in it; so, also, if rubbed upon white paper, it
blackens it more than good powder does; but, if it be of a kind
of azure colour, it is a good indication. If on crushing it with
the fingers, the grains break easily, and turn into dust, without
feeling hard, it is a criterion, that it has too much coal; or, if in
pressing it under the fingers upon a smooth hard board, some grains
feel harder than the rest, it is inferred that the sulphur is not
well mixed with the nitre. By blasting two drachms of each sort on a
copper plate, and comparing it with approved powder. In this proof
it should not emit any sparks, nor leave any beads or foulness on
the copper. The method of _burning_, which is commonly employed, Mr.
Robins observes, is to fire a small heap on a clean board, and to
attend nicely to the flame and smoke it produces, and to the marks it
leaves behind on the boards.

Another trial of powder is to expose it to the atmosphere. One pound
of each sort, accurately weighed, is exposed to the atmosphere for
17 or 18 days; during which time, if the materials are pure, it will
not increase any thing material in weight, by attracting moisture
from the air. One hundred pounds of good powder should not absorb
more than twelve ounces, or somewhat less than one per cent. See Mr.
Coleman's account of the manufacture of powder in England, page 110.

To determine the strength of powder in the easiest manner, is by
comparing its effect with improved powder; as, for instance, by using
a given weight of powder, as two ounces, and discharging a ball of a
known weight, say 64 pounds, from an 8 inch mortar. The best cylinder
powder generally gives about 180 feet range, and pit 180, with a ball
and charge of the above weights; but the weakest powder, or powder
that has been reduced, &c. only from 107 to 117 feet.

The practice adopted in England, we are told, is, that the merchant
powder, before it is received into the king's service, is tried
against powder of the same kind made at the king's mills, and it is
received if it gives a range of 1/20 less than the king's powder,
with which it is compared. In this comparison, both sorts are tried
on the same day, and at the same time, and under exactly the same
circumstances.

James (_Mil'y Dictionary_, p. 348) remarks, that the proof of powder
as practised by the board of ordnance, besides that of comparing
it by combustion on paper, is that 2 drachms, when put into the
eprouvette, must raise a weight of 24 pounds to the height of 3-1/2
inches.

According to Bottée and Riffault, before gunpowder is received into
the arsenals of France, for service, it undergoes a variety of
proofs; and the instructions for that purpose are contained under
forty-two heads, embracing, at the same time, the specific duties of
the officer employed for that service. The principal points, however,
refer to a standard proof, made with the eprouvette, and differ, in
no essential part, from the methods practised elsewhere. There is a
uniformity in the French service, which cannot but be admired. In
every thing which relates to the ordnance especially, even in the
most minute details, the French, without doubt, exceed any other
nation.

Having examined the different kinds of proof, not only for
gunpowder, but for cannon and small arms, as established by an act
of parliament, it appears, that musket powder undergoes another
description of proof. A charge of four drachms of fine grain or
musket powder in a musket barrel, should perforate, with a steel
ball, a certain number of half inch wet elm boards, placed 3/4 inch
asunder, and the first 39 feet 10 inches from the barrel. The powder
manufactured at the Royal Powder Mills generally passes through
fifteen or sixteen, and restored powder, from nine to twelve.

There are other contrivances made use of, such as _powder-triers_,
acting by a spring, commonly sold at the shops, and others again that
move a great weight, throwing it upwards, which is an imperfect kind
of eprouvette.

Dr. Hutton is of opinion, that the best eprouvette is a small cannon,
the bore of which is about one inch in diameter, and which is to be
charged with two ounces of powder, and with powder only; as a ball is
not necessary; and the strength of the powder is accurately shown, by
the _arc of the gun's recoil_.

The whole machine is so simple, easy, and expeditious, that, as Dr.
Hutton remarks, the weighing of the powder is the chief part of the
trouble; and so accurate and uniform, that the successive repetition,
or firings, with the same quantity of the same sort of powder, hardly
ever make a difference in the recoil of the one-hundredth part of
itself.

Gregory (_Treatise of Mechanics_, vol. ii, p. 178) has given a more
particular description of the eprouvette of Dr. Hutton; namely, that
it is a small brass gun, 2-1/2 feet long, suspended by a metallic
stem, or rod, turning, by an axis, on a firm and strong frame, by
means of which, the piece oscillates in a circular arch. A little
below the axis, the stem divides into two branches, reaching down to
the gun, to which the lower ends of the branches are fixed, the one
near the muzzle, the other near the breech of the piece. The upper
end of the stem is firmly attached to the axis, which turns very
freely by its extremities in the sockets of the supporting frame; by
which means, the gun and stem vibrate together in a vertical plane,
with a very small degree of friction. The charge is the same we have
mentioned, usually about two ounces, without any ball, and then
fired; by the force of the explosion, the piece is made to recoil or
vibrate, describing an arch or angle, which will be greater or less,
according to the quantity or strength of the powder.

To measure the quantity of recoil, and consequently the strength of
the powder, a circular brazen or silver arch of a convenient extent,
and of a radius equal to its distance below the axis, is fixed
against the descending two branches of the stem, and graduated into
divisions, according to the purpose required by the machine: _viz._

1st. Into equal parts, or _degrees_, for the purpose of determining
the angle actually described in the vibration.

2nd. Into equal parts, according to the _chords_, being, in fact, 100
times the double sines of the half angles, and running up to 100, as
equivalent to 90 degrees.

3d. Into unequal parts, according to the versed sines; they are,
in truth, 100 times the versed sines of our common tables, 141-1/2
corresponding with 90 degrees. These serve to compare the forces.

The divisions in these scales are pointed out by an index, which is
carried on the arch during the oscillation, and then, stopping there,
shows the actual extent of the vibration. Two ounces of powder, give,
on an average, according to the experiments of professor Gregory,
about 36 on the chords, or about 21° on the arch. A more detailed
account, with diagrams, may be seen, by consulting Hutton's Tracts,
vol. iii, p. 153.

The eprouvette constructed by the late Mr. Ramsden, differs from the
preceding simply by the gun's recoiling in a direction parallel to
itself, instead of its vibrating as a pendulum. The gun is suspended
by two hanging frames, which serve to make it rise and fall, during
its recoil and return, so as always to retain the horizontal
direction. The degrees are measured upon a fixed arch, by means of a
moveable index, nearly as in Dr. Hutton's eprouvette.

We remarked, that the common powder-triers are small strong barrels,
in which a determinate quantity of powder is fired, and the force
of expansion measured by the action excited on a strong spring,
or a great weight. The French eprouvette is usually a mortar of
seven inches (French) in caliber, which with three ounces of powder
should throw a copper globe of sixty pounds weight to the distance
of 300 feet. No powder is admitted that does not answer this trial.
This eprouvette, however, has been improved, as we shall mention
hereafter. These methods have been objected to, the former because
the spring is moved by the instantaneous stroke of the flame, and
not by its continued pressure, which is somewhat different; and the
other, on account of the tediousness attending its use, when a large
number of barrels of powder are to be tried.

J. Bodington of London, invented a machine to try the force of
gunpowder. M. the chevalier d'Arcys made an eprouvette on the
principle of Mr. Robins. M. Le Roy proposed to employ the different
elastic forces of inflammable air, but his method has never been
used. M. Tresnel also proposed an eprouvette, which was announced in
the French journal, entitled _Nouvelles de la République des Lettres
et des Arts_, par M. de la Blancherie, for 1782, p. 190.

It is hardly necessary to observe, that the eprouvette has undergone
some improvements: thus, the eprouvette of Darcy consists of a cannon
suspended at the extremity of a bar of iron, and the graduated arc
measures the recoil; the eprouvette of Regnier is nearly the same,
and the arc determines the force of the powder.

A description of mortar-eprouvettes generally, may be seen in the
work of MM. Bottée et Riffault, (_Traité sur l'art de Fabriquer la
poudre à canon_,) and in the Memoirs of Proust (_Journal de Physique_,
tome lxx, _et suiv._), &c.

I saw a model of an improved eprouvette, which appeared to possess
every advantage, at the Ordnance Arsenal near Albany; an index hand
moved in an arc.

Quicklime is said to increase the force of powder. Dr. Baine says,
that three ounces of pulverized quicklime being added to one pound
of gunpowder, its force will be augmented one-third; shake the whole
together, till the white colour of the lime disappears.

The preservation of gunpowder in properly constructed magazines, of
which we will have occasion to speak hereafter, is a subject that
should claim our attention. The greatest difficulty, if any, exists
at sea, and on this head we have a variety of opinions.

Mr. James (_Military Dictionary_, p. 348) says, that it has been
recommended to preserve gunpowder at sea by means of boxes lined with
sheet-lead. M. D. Gentien, a naval officer, tried the experiment by
lodging a quantity of gunpowder and parchment cartridges in a quarter
of the ship which was sheathed in this manner. After they had been
stowed for a considerable time, the gunpowder and cartridges were
found to have suffered little from the moisture; whilst the same
quantity, when lodged in wooden cases, became nearly half destroyed.

It has been recommended to line powder magazines with lead, as a
mean for preserving the powder from dampness. The lead, it seems, so
far attracts moisture, as to condense it. In the last volume of the
_Transactions of the American Philosophical Society_, is a memoir
on _leaden_ cartridges, by Wm. Jones, Esq. the late secretary of
the navy, which, besides preserving the powder, has advantages over
either paper or flannel. See Magazine.

What is termed the _analysis of gunpowder_, is nothing more than the
separation of its component parts, and determining the relative
proportions of its respective ingredients. We may indeed examine
the quality of the nitrate of potassa, by dissolving a portion of
powder in distilled water, and employing the reagents mentioned under
the head of nitre; but for the purpose of separating, as well as
determining the proportion of saline matter, charcoal and sulphur,
it may be readily accomplished in the following manner: Take a given
quantity of gunpowder and affuse it in distilled water sufficient
to dissolve the salt; after suffering it to remain for some time,
applying heat to assist the solution, decant the whole upon a filter
of unsized paper. The saltpetre and other saline matter will pass
through, and the sulphur and charcoal remain on the filter. By
evaporating the solution to dryness, and weighing it, the quantity
of saltpetre will be found; or, after drying the mass on the filter,
and weighing it, by subtracting its weight from that of the original,
it will give the loss sustained, which of course is the saltpetre.
By exposing the mass to a heat sufficient to evaporate the sulphur,
it will be expelled; the loss sustained will indicate its quantity,
and the weight of the residue the proportion of charcoal. The sulphur
may be even separated by subjecting gunpowder itself to the action
of a well regulated heat; it will sublime, and leave the nitre and
charcoal. It takes a much higher temperature to inflame gunpowder
than is required to volatilize sulphur. The method of extracting the
nitre from damaged powder, we have already noticed. See _nitre_.
This process also depends on the solubility of the nitre, and the
insolubility of the charcoal and sulphur. Bishop Watson, in his
_Chemical Essays_, proposed the examination of gunpowder by solution
and sublimation; a process sufficiently accurate. If it should be our
object to ascertain the presence and quantity of foreign substances,
in the saltpetre, this may be accomplished by following the process
already given, viz: by collecting the precipitates, &c. determining
their weights, and making the necessary allowance, for the new
compounds, as the carbonates of lime, sulphate of barytes, muriate of
silver, and the like.

Baumé proposed the analysis of powder by sublimation, in order
to separate the sulphur, using however a graduated heat. Another
mode consists in distilling the powder in a retort with water,
and collecting the sulphur and sulphuretted hydrogen gas, and
then separating the charcoal, &c. A third process was recommended
by Pelletier, after the separation of the nitre, by subliming a
mixture of the residue with mercury, which, however, presents no
advantages. The use of nitric acid has also been recommended, in
order to acidify the sulphur. For this purpose nitric acid is poured
on the residue, and the whole is digested for some time, renewing
the acid as it is decomposed. By this means the carbon, as well as
the sulphur, is acidified, and carbonic acid gas with deutoxide of
azote are disengaged, leaving the sulphuric acid formed by the union
of oxygen with the sulphur, in the remaining fluid, from which it
is separated by nitrate of barytes, and its quantity ascertained by
the sulphate of barytes produced. The proportion of sulphur, in the
sulphuric acid, is then calculated.

Caustic potassa has been employed for the separation of the sulphur
from the charcoal. It unites with the sulphur, forming a sulphuret;
and as sulphuretted hydrogen gas is also produced, the sulphuret must
likewise contain the hydroguretted sulphuret of potassa. The charcoal
is not acted upon.

M. Vito Caravelli, professor of chemistry at Naples, (_Elements
d'Artillerie_, 1773,) has given a more simple process for the
separation of these substances, which depends on their specific
gravity. When mixed with water, the sulphur will deposite, and the
charcoal float on the fluid.

Vauquelin directed his attention to this subject, and has recommended
various processes, not only for the separation of the sulphur and
charcoal, but also the nitre.

The process of Smithson Tennant is nearly of the same nature.

The separation of sulphur from charcoal may be effected more
perfectly, according to Brande, by introducing the mixture into a
small retort furnished with a stop cock, exhausted, and filled with
chlorine gas; the chlorine will unite with the sulphur, forming a
chloride, and leave the charcoal, which may be washed, dried, and
weighed.

Baumé found, that when all the sulphur is expelled which will be
driven off in the heat, a certain portion will still remain, and not
burn away at a lower temperature than will consume the charcoal; so
that to the last the burning residue will smell strongly sulphurous.
This retained portion of sulphur he finds, by the results of many
other experiments, to be very uniformly about one-twenty-fourth part
of the whole sulphur employed; whence, for all common purposes, an
adequate correction may be made, by estimating that the slow weak
combustion of the residue, after the nitre has been extracted,
destroys only 23/24ths of the sulphur instead of the whole. On trying
to separate them by an alkaline solution, he found some of the
sulphur to remain undisturbed, and still adhering to the charcoal.
In consequence of this circumstance, it is recommended, to insure
a perfect analysis, to separate the nitre in the first place from
gunpowder, by hot water, and to treat the residue with nitric acid.
After the sulphur is acidified, the addition of nitrate or muriate
of barytes will separate, effectually, the sulphuric acid from the
fluid, and form a sulphate of barytes; this being collected, washed,
dried, and weighed, will give the quantity of sulphuric acid, and
of sulphur in the acid, by the well known proportion of acid in the
salt, and of sulphur in the acid. One hundred parts of sulphate of
barytes, when perfectly dry, indicate fourteen and a half parts of
sulphur; or, which is the same, according to Chenevix, one hundred
and fifty-five grains denote twenty-two and a half grains of sulphur.

The observations of M. Champy and professor Proust on _humid powder_,
seem to place the quantity of water absorbed, at 8, 10, and 14 per
cent. These proportions, it is evident, depend greatly on the quality
of the nitre; and if deliquescent salts exist in any quantity, the
absorption, and consequently the increase of weight must be greater.
Chemical examination will readily determine this fact.

The different sorts of gunpowder are usually distinguished by
marks on the heads of the barrels. Gunpowder marks are various.
All gunpowder for service is mixed in proportions according to its
strength, so as to bring it as much as possible to a mean and uniform
force. This sort of powder, says Adye, (_Bombardier and Pocket
Gunner_,) is marked with a blue L. G. and the figure 1/2; or with F.
1/2 G. and the figure 3, whose mean force is from 150 to 160 of the
eprouvette. This is the powder used for practice, for experiments,
and for service. The white L. G. or F. G. is a second sort of powder
of this quality. It is sometimes stronger but not so uniform as the
L. G. It is, therefore, generally used in filling shells, or such
other things as do not require accuracy. The red L. G. F. G. denotes
powder in the British service, made at the King's mills, with the
coal made in cylinders, and is used at present only in particular
cases, and in comparisons, and to mix with other sorts to bring them
to a mean force. The figures 1, 2 or 3 denote that the powder is made
from saltpetre, obtained from the rough. Other marks are also in use
to designate the rifle, musket, cannon powder, and the like.

Powder merchants recover damaged gunpowder, by putting a part of the
powder on a sail cloth, and adding an equal quantity of good powder,
which is well mixed with it, and the mixture is then dried.

_Sec. VIII. Of Lampblack._

Lampblack, which is nothing more than a finer kind of coal, is so
named from its being produced and originally made by the combustion
of oil in lamps. It is hardly necessary to say, that it is formed in
the combustion of turpentine, various species of the _pinus_, tar,
pitch, rosin, &c. as all these substances yield it more or less, and
of different qualities. It is the result of imperfect combustion;
for, if the combustion were rapid, and the smoke itself consumed,
we would then have only carbonic acid. This fact is exemplified in
the argand lamp, which, on account of the glass cylinder, consumes
its own smoke. The process of forming lampblack is conducted in
_lampblack houses_. After the combustion has ceased, the soot or
lampblack is swept down, as it collects above and on the sides of
the room. When it is obtained by burning the dregs and coarser parts
of tar, furnaces of a particular construction are used. The smoke is
conveyed through tubes into boxes, each covered with linen, in the
form of a cone. Upon this linen the soot is deposited, from which
it is, from time to time, beaten off into boxes, and afterwards
packed in barrels for sale. There is also a very fine black, superior
in many respects to lampblack, especially in making the ink for
copperplate printers, prepared by carbonizing grape stalks, &c. in
close iron vessels.

There are two kinds of lampblack in common use. One is the light
soot, from burning wood, of the pine and other resinous kinds,
usually made in Sweden. In Sweden the impure turpentine is also burnt
for this purpose. It is collected from incisions made in pine and
fir-trees, and the turpentine is boiled down with a small quantity of
water, and strained, while hot, through a bag; and while this part is
used for another purpose, the dregs and pieces of bark remaining in
the strainer, are burnt in a low oven, whence the smoke is conveyed
through a long passage into a square chamber, which contains a sack,
as above stated, where the greater part of the lampblack collects,
and the remainder is caught in the chamber.

The other kind of lampblack is formed by carbonization, a process
similar to that for preparing the black, called _blue-black_, from
grape stalks, or for preparing the German black, a pigment made by
charring principally the lees of wine and husks of grapes.

The lampblack made in Philadelphia, for the purpose of printers' ink,
is prepared by the combustion of tar. One barrel of Carolina tar will
produce forty pounds of soot or lampblack.

A patent was granted 1798 to a Mr. Row, (_Repository of Arts_, vol.
x.) for a newly invented mineral lampblack. It is nothing more than
the smoke obtained by the combustion of pit coal. In the county of
Sarrbrook on the Rhine, are some establishments for making coke and
lampblack at the same time; and from 100 lbs. of coal, 33 lbs. of
coke, and 3-1/2 of lampblack are obtained. Jeanson (_Archives des
Découvertes_, &c. i, p. 21) has described a process for carbonizing
oil.

Lampblack has the same chemical properties as charcoal, and being
remarkably fine, and containing sometimes a portion of oil, is used
on that account in the composition of some fire-works. Its quality
may be known by its colour, and, when burnt, leaving no residue. It
may be sufficient to remark, that like charcoal, it decomposes nitric
acid; and the nitrates, when mixed with it, and projected into a
red-hot crucible, will deflagrate or produce a vivid combustion. It
may therefore be used in all kinds of fire-works, in which charcoal
is employed. Concentrated nitric acid, when poured on lampblack,
previously dried, will produce combustion. It is to the carbon, as
well as the hydrogen, in oil of turpentine, that turpentine inflames
when brought in contact with nitric acid; and although much charcoal
is deposited, yet a considerable part passes off in the state of
carbonic acid gas. By a proper treatment, lampblack like charcoal
may be converted into artificial tannin by nitric acid. It has also
antiseptic qualities; but to be used for this purpose it should first
be exposed to heat, in order to drive off any oil which it may have
contracted, or with which it might be contaminated. The quality of
lampblack may, we suspect, be improved by bringing it to a state of
ignition in close iron vessels. If required intensely black, as for
the making of printers' ink, this process might be advantageously
used. Mixed with gum water, it makes a durable writing ink, or,
according to Mr. Close, by mixing it with a solution of copal in oil
of lavender. This ink is not, like the common kind, acted upon by
acids.

_Sec. IX. Of Soot._

Soot, or that substance formed by the combustion of wood, &c.
which collects in chimnies, is used in some of the pyrotechnical
preparations, partly to assist the flame, and partly to modify its
appearance. It is found, that soot, produced by the combustion of
wood, is formed by the condensation of the carbon evolved in the
smoke. It also contains volatile products, the nature of which,
depends on the kind of combustible. Wood-soot is considered a good
manure, on account of the carbon and some volatile salts, it is
said to contain. That it contains ammonia, is evident, since it may
be detected by experiment; and that this alkali is combined with
carbonic acid, and sometimes with muriatic acid, a number of facts
prove. Soot, then, when used in fire-works, may, like sal ammoniac,
but in a lesser degree, produce a particular coloured flame. When
soot is well washed in water, in order to free it from saline and
other soluble matter, and probably from pyroacetic acid, and then
pulverized, it forms the pigment called _bistre_. It is a fact,
that the excrement of some animals, the camel for instance, which
feed on saline vegetables, when burnt, will yield a soot, which
contains an abundance of muriate of ammonia, or sal ammoniac. Hence,
by re-subliming this soot, sal ammoniac was originally prepared in
Egypt. The quantity of muriate of ammonia, contained in the soot of
camels' dung, is considerable. It is found that 26 lbs. of soot yield
on an average 6 lbs. of that salt; See _Sal Ammoniac_. Camels' dung,
and in fact the dried excrement of animals, furnish a very good fuel.
In Egypt it is used with advantage. The soot of oil, &c. is of a
different kind; it is the substance, which forms our lampblack.

_Sec. X. Of Turpentine, Rosin, and Pitch._

All these substances enter into the composition of fire-works, either
to increase the rapidity of combustion, as in incendiary fire-works,
or, in some cases, as with rosin, to produce a coloured flame. That
they contain carbon and hydrogen, as their principal ingredients, is
well known; to which we may attribute their rapid combustion, and the
facility with which they decompose nitrous salts. The Greek fire, for
example, owed, it is said, its powerful effect to turpentine, which,
with other substances employed, made the composition remarkably
inflammable, and the decomposition of the nitre, (which some say it
contained) so rapid, as even to defy the action of water.

All of the turpentines are obtained from different species of pinus.
Common turpentine is the resinous juice, which exudes chiefly from
the _Pinus Sylvestris_, or Scotch fir, and is obtained by boring
holes into the trunks of the trees, early in the spring, and placing
vessels beneath for its reception. This turpentine, and in fact all
others, are composed of rosin and a volatile oil. The latter is
obtained by distilling the turpentine with water. It passes over
with the water, from which it is afterwards separated, and is then
known by the name of the essential oil, or spirit of turpentine. The
substance, remaining in the still, is common rosin, or yellow rosin,
known likewise by the names of _fidlers' rosin_ and _colophony_. Tar
is also obtained from the roots and refuse parts of the fir tree, by
cutting them in billets, piling these in a proper manner, in pits or
ovens, formed for the purpose, covering them partly over, and setting
them on fire. During the combustion, a black and thick matter, which
is tar, falls to the bottom, and is conducted into barrels.

Pitch is nothing more than tar boiled down to a solid consistence; it
is usually made, however, by melting together coarse hard rosin, and
an equal quantity of tar. The ancient pitch possessed a flavour and
fragrance. White pitch is the same as the white turpentine.

Melted pitch, sulphur, and camphor, mixed, when nearly cold,
with pulverized saltpetre, and afterwards thinned with spirit of
turpentine, will form a composition, that is very inflammable, and
will almost resist the action of water. A similar composition must
have formed the Greek fire, of which, according to Beckman, there
were several kinds.

The turpentine trees furnish various products: Thus, the Pinus
Abies, or spruce fir, yields the Burgundy pitch, and its branches
produce the Essence of Spruce; but other species of pinus are used
for the same purpose, which are nearly allied to it, and which grow
abundantly in Canada. From the _Pinus laryx_, or larch, Venice
Turpentine is obtained; but that sold, is usually made by melting
rosin, and adding the spirit of turpentine. From the sap of the
larch, the Russians prepare a gummy substance, known in Russia by the
name of _Orenburg gum_. Turpentine is extracted in France, in great
quantity, from the _pinus maratima_. Gallipot, colophony, tar, pitch,
&c. are likewise obtained from it.

The turpentine of cedar, according to Dr. Pocoke (_Travels through
Egypt_) was employed by the Egyptians for embalming, the operation
being performed in several ways. It was injected, and used with salt,
nitre, &c.

Pitch, tar, and turpentine all enter into sundry compositions, used
in war. The different incendiary preparations, noticed in the last
part of the work, are composed, in general, of either one or all of
these substances. Their use is obvious. Being very inflammable, and
brought in contact with gunpowder, nitrate of potassa, &c. they burn
with great rapidity, and consume every thing before them. Hence the
tourteaux of the French, tarred links, and fascines, carcasses, &c.
owe their effect to the presence of these substances.

Rosins are considered to be volatile oils, saturated with oxygen.

_Thus_, or frankincense, of which there are several varieties, has
been long used in fire-works; it is frequently employed in the
composition of odoriferous fire. It is obtained from the pinus
abies, and appears in _tears_. During winter, the wounds made in fir
trees become incrusted with a brittle substance, called _barras_ or
_gallipot_, consisting of rosin united with a small portion of oil.
All rosins, according to the experiments of Gay-Lussac, and Thenard,
(_Recherches physico-chimiques_) are composed of a great quantity of
carbon and hydrogen, united with a small quantity of oxygen. To this,
we attribute their great inflammability, and it enables us to account
for the rapid decomposition of nitre, in those preparations, in which
nitre and resinous substances are employed. See _General Theory of
Pyrotechny_, sec. ii.

For the accension which takes place by mixing oil of turpentine and
nitric acid, see the properties of nitric acid, under the head of
_nitre_.

Morey (_Silliman's Journal_, vol. ii, p. 121) observes, that a
small quantity of spirit of turpentine being added to a mixture of
iron-filings, sulphuric acid, and water, the hydrogen gas produced,
will burn with a very pleasant white flame, and without smoke. He
also observes, that, if the vapour of spirit of turpentine be made to
pass through a tube, covered at the upper end with a fine wire gauze,
it burns with much smoke; but, if a quantity of atmospheric air be
allowed to mix with it, the smoke ceases, and the flame continues
white. If more still be added, the flame lessens, and becomes partly
blue. By adding still more and more, it will burn with a very small
flame, entirely blue, and with a singular musical sound. If still
more be added, the flame, and every ray of light cease; but that the
combustion still continues, is certain, from the explosive detonating
noise, continuing to be distinctly heard.

Mr. Morey further remarks, that, if tar, containing a considerable
proportion of water, is dropped on brick or metal, at a temperature,
which will readily evaporate them, the vapours will burn with white
shooting streaks, much flame, and without smoke, while the water
lasts. Inflamed drops of tar, burn, while falling, with a red
flame, and much smoke; but, on reaching boiling water, the smoke
instantly disappears, and streaks of a white flame shoot up. He also
says, that, if water in one cylinder be made to boil, and the steam
be led to the bottom of another, containing rosin, or tar, at a
high temperature, after passing up through it, the water, together
with the vapourized portion of the rosin or tar, will, when the
preparations are properly regulated, burn with an intense _white_
flame, and _no smoke_; much the greater part of which appears, (by
alternately shutting the steam out, or letting it in) to be derived
from the water; and also, that if steam be led over the surface of
tar in a cylinder, and made to force out a small stream of it through
a pipe, into which a quantity of steam is also admitted, and made to
mix intimately with it, they burn, with a great body of flame and
intense heat, and without smoke, provided the proportions are well
regulated. These facts are remarkable, and may probably lead to some
useful applications. That water is decomposed, appears more than
probable. If water is thrown, in considerable quantities, on oil or
tar, in a state of inflammation, as Morey observes, the flame is
greatly increased; and if ever so small a drop of water fall into oil
at a temperature near boiling, an explosion will take place. He draws
the following conclusion, from these circumstances; that we have only
to pass the steam of water through oil, heated to the temperature, at
which it boils, or takes fire, to produce combustion.

_Sec. XI. Of Common Coal, or Pitcoal._

All the variety of coals, belonging to the coal family, are composed
principally of charcoal and bitumen, with small quantities of earthy,
and metallic matter. Whether we consider the formation of coal,
the localities or situation in which it occurs, whether in beds or
strata, accompanying other minerals, such as clay-slate, bituminous
schistus, sandstone, &c. is of no moment, except so far as the
situation in which it is found, indicates or determines its character
and qualities. The different kinds of coal owe their variety to the
presence or absence of bituminous matter, whether great or small, the
quantity of the carbonaceous ingredient, and the presence or absence
of anthracite, and other foreign substances. Coal, which is, or ought
to be preferred in fire-works, should contain the greatest quantity
of bituminous matter; and, while it contains the due proportion of
carbon, should be entirely free from anthracite. Coal, and all other
inflammable fossils, are characterized by their inflammability,
insolubility in water, alcohol, and acids, and by their specific
gravity, which scarcely exceeds 2, unless loaded with foreign
matter. Coal surcharged with bitumen, burns with a bright flame, and,
by distillation, affords more carburetted hydrogen gas, which is used
for _gas light_. Common coal, or pitcoal, burns in cakes, more or
less, during combustion. Besides charcoal and bitumen, it contains
sometimes pyrites, sulphate of iron, and earth. Slate-coal, however,
contains more clay.

The collieries, from which pitcoal is obtained, are more or less
extensive in England, and elsewhere. Immense beds of coal are found
near Pittsburgh, and Richmond. The Lehigh, and other localities in
the United States, produce it also in abundance, but of various
qualities. Coal districts, or places in which it is found, may be
considered a valuable acquisition to a country; and as coal is so
essential in many manufactories, it is a satisfaction to know, that
our resources in this particular, are almost inexhaustible;--a fact,
which shows, that, while our national industry is the main pillar
of national independence, in its true acceptation, the arts, which
require a supply of coal, will, for centuries to come, be abundantly
furnished with it.

When coal is exposed to the action of heat, in iron retorts or
cylinders for the preparation of coal gas, or when it is exposed
to heat in coke-ovens, the bitumen, &c. are disengaged, and there
remains a coal called coke. Coke, therefore, is nothing more than
charred pitcoal.

Mr. Mushet made some valuable experiments on the carbonization
and incineration of coals. He found that the Scotch cannel-coal
afforded 56.57 volatile matter, 39.43 charcoal, and 4 ashes; while
the stone-coal, found under basalt, gave 16.66 volatile matter,
69.74 charcoal, and 13.6 ashes, and oak wood, 80.00 volatile matter,
19.5 charcoal, and 0.5 ashes. The quantity of gas, however, depends
entirely on the quality of the coal. A temperature of about 600° to
700° is sufficient to disengage it. A pound of good cannel coal,
properly treated in a small apparatus, will yield five cubic feet of
gas, equivalent in illuminating power to a mould candle, six in the
pound. One pound of coal, on a large scale, affords only 3-1/2 cubic
feet of gas. A gas jet, which consumes half a cubic foot per hour,
gives a steady light equal to that of a candle of the above-mentioned
size.

The cannel coal, known in Scotland by the name of parrot coal, is
very inflammable, takes fire immediately, and produces a brilliant
flame. It is used by the poor as a substitute for candles. This coal,
we have seen, furnishes an abundance of carburetted hydrogen gas. It
has the appearance of jet, and admits of being turned in a lathe.

Stone coal, Kilkenny coal, Welch coal, and glance coal consist almost
entirely of charcoal; and hence, when laid on burning coals, they
become red-hot, emit a blue lambent flame, in the same manner as
charcoal, and at length are wholly consumed, leaving behind a portion
of red ashes. They burn without smoke or soot.

The pitch coal, which has a brownish-black colour, and is generally
found massive in plates, the bovey coal, called brown coal, and
bituminous wood, with the anthracite coal, and some others of lesser
note, form the remaining varieties of coal.

When coal is employed in fire-works, it is to be pulverized, and
sifted in the usual way. For some purposes it is preferred to
charcoal, in consequence of the bitumen it contains, which appears to
contribute to the rapidity of the combustion. It is to be observed,
that, as the base of coal is carbon, its action is the same as
charcoal, and therefore, by producing the same effects, or nearly
so, as charcoal itself, the phenomena it presents are analogous.
As 12.709 parts of carbon, according to Kirwan, are required to
decompose 100 parts of nitrate of potassa, we may readily ascertain
the quantity of real carbon in any specimen of coal. According to
Kirwan, 50 grains of Kilkenny coal will decompose 480 grains of
nitrate of potassa, from which it is inferred, that ten grains would
have decomposed 96 of nitrate of potassa, precisely the same quantity
of charcoal, which would have produced the same effect. Therefore,
Kilkenny coal is composed almost entirely of carbon. Cannel coal,
when treated in the same manner with nitrate of potassa, left a
residuum of 3.12 in the hundred parts of earthy ashes; and 66.5 of
it were required to decompose 480 grains of nitrate of potassa, but
50 of charcoal would have been sufficient. From this experiment,
it appears, that 66.5 grains of cannel coal contain 50 grains of
charcoal, and 2.08 of earth; the remaining 14.42 grains must be
bitumen. In a similar manner, by knowing the quantity of coal
required to decompose a given quantity of nitrate of potassa, when
melted in a crucible, the quantity of carbon in any variety of this
substance may be ascertained.

With respect to the earthy and metallic ingredients of coal, we may
ascertain them by burning the coal, with free access of air. What
remains unburnt must be considered an impurity. Its weight may be
ascertained, and its nature by analysis. As the object, however, is
generally to determine the relative proportion of combustible matter,
or carbon, which different species of coal are capable of yielding,
that point may be determined in the manner already stated.

That coal originates from vegetables, whatever opinion may be formed
to the contrary, we may fairly infer from a variety of vegetable
remains, and impressions of animals that are both found in the strata
of coal, and in earthy strata above and below them. Of its submarine
origin, there can also be no doubt; or why do we find in it shells,
the impression of fish, and other productions of the ocean? That
coals _grow like vegetables_, an opinion with the uninformed, is
contrary to fact, and the nature of things.

We may notice, in this place, another substance which sometimes is
found partially carbonized; we mean turf.

Turf or peat, obtained from morasses, consists of a multitude or
congeries of vegetable fibres, partly in a decomposed state, and is
frequently so inflammable as to inflame by a spark. Very extensive
morasses are found in some countries from which the inhabitants are
supplied with fuel. Some improvements in the manner of preparing
turf for use, have been made; that of charring it in kilns is one.
By this process it kindles sooner, burns with less air, and forms
a moderate and uniform fire, without much smoke, though it is not
so lasting as that produced by turf. The method of reducing turf to
coal is still practised in some parts of Bohemia, Silesia, and Upper
Saxony, which was first proposed in 1669, by John Joachim Becher,
who also recommended, at that time, a process for depriving coals
of their _sulphur_, by burning them in an oven, and the use of the
oil procured from them. What are our modern patents on this subject?
What are lord Dundonald's coke ovens and coal tar? Are they original?
Boyle (_Usefulness of Natural Philosophy_,) speaks of Becher's
invention. Anderson, (_History of Commerce_,) however, observes,
that something of the kind was attempted before Becher's time; for
in the year 1627, John Hacket and Octavius Strada obtained a patent
for their invention of rendering coals as "useful as wood for fuel in
houses, without hurting any thing by their smoke."

With respect to turf, it appears that Hans Charles von Carlowitz,
to save wood, introduced the use of it in Saxony, in the smelting
houses, in 1708.

Turf has been known for a long time. It was used from the earliest
periods, in the greater part of Lower Saxony, and throughout the
Netherlands; as is fully proved by Pliny's account of the Chauci,
who inhabited that part of Germany. Pliny (_Hist. Nat. lib._ xvi, c.
i.) observes, that they pressed together with their hands, a kind of
mossy earth which they dried by the wind rather than by the sun, and
which they used, not only for cooking their victuals, but also for
warming their bodies. We also read that a morass in Thessaly, having
become dry, took fire, and the same thing ensued in some part of
Russia, where a morass burned several days and did much damage. Very
dry turf is nearly as inflammable as spunk, and when prepared with
nitre, has been used for the same purpose. See _Pyrotechnical sponge_.

Ure (_Chemical Dictionary_) observes, that "turf has been charred
lately in France, it is said by a peculiar process, &c." The truth
is, that the _charring_ of turf is by no means a recent invention, as
we stated above. Sonnini (_Journal_, &c.) says, that it is superior
to wood. It kindles slower than charcoal of wood, but emits more
flame and burns longer. In a gold-smith's furnace, it fused eleven
ounces of gold in eight minutes, while wood charcoal required sixteen.

Turf frequently contains phosphoric acid; for bogs or morasses, and
bog-iron ores abound, more or less with it, in different states of
combination. The _siderite_ of Bergmann which he supposed to be a
peculiar metal, and found in bog-ore, is a phosphate of iron. The
native Prussian blue, which also occurs in such localities, is
generally admitted to be a combination of phosphoric acid iron and
alumina.

_Sec. XII. Of Naphtha, Petroleum, and Asphaltum._

Naphtha, petroleum, and asphaltum are all modifications of bituminous
oil; and as they are all inflammable, naphtha being the most so, they
have been used in the preparation of fire-works.

It will be sufficient to remark, that naphtha or rock oil is a yellow
or brownish bituminous fluid, of a strong, penetrating odour, and
so light as to float on spirits of wine. By exposure to the air, it
acquires the consistence of petroleum. It takes fire on the approach
of a lighted taper, and burns with a bluish flame, yielding a thick
smoke. Plutarch and Pliny both affirm, that the substance with which
Medea destroyed Creusa, the daughter of Creon, was naphtha. She sent
a dress to the princess, which had been immersed in, or covered over
with the oil, and which burst into flames as soon as she approached
the fire of the altar. Plutarch relates that Alexander the great,
was amused and astonished with the effects of naphtha, which were
exhibited to him at Ecbatana. On the shores of the Caspian sea, it
is burnt in lamps, instead of oil. There are copious springs of this
oil in that neighbourhood, and it is sometimes obtained by distilling
bituminous substances.

Hanway (_Travels through Russia into Persia_, i, 263,) mentions the
naphtha of Baku, and remarks that the earth is strongly impregnated
with it; for, he adds, by taking up two or three inches of the
surface, and applying a live coal, the part which is so uncovered,
immediately takes fire, almost before the coal touches the earth.
Eight horses were consumed by the fire from naphtha, being under a
roof where the surface of the ground was turned up, and, by some
accident took fire. A cane, or tube, even of paper, set two inches
in the ground, and the top of it touched with a live coal, and blown
upon, immediately emits a flame, without hurting either the cane or
paper, provided the edges be covered with clay. Three or four of
these lighted canes will boil water in a pot.

Pinkerton, (_Petralogia_ ii, p. 148,) speaks of the naphtha of Baku,
which exists on the western side of the Caspian sea, being carried to
Constantinople, "where it formed the chief ingredient of the noted
composition called the Grecian Fire; which, burning with increased
intensity under water, became a most formidable instrument against an
inimical fleet." See _Greek fire_.

Naphtha is obtained of several qualities by suffering it to remain
in pits or reservoirs. The Persians, who use it in their lamps, and
to boil their food, find it to burn best with a small mixture of
ashes. They keep it at a small distance from their houses, in earthen
vessels, under ground, to prevent any accident by fire, of which it
is extremely susceptible.

Hanway speaks also of what is called the _everlasting fire_, about
ten miles from Baku, which is an object of devotion to the followers
of Zoroaster. Near the altar of their temple, he observes, is a
large hollow cane, from the end of which issues a blue flame, which
the Indians pretend has continued to burn ever since the flood, and
which, they fancy, will last to the end of the world.

We have no hesitation in believing, that the ancients made use of
this oil in their exhibitions; and, from its properties, that when
mixed with other substances, it would make a brilliant fire-work.

Petroleum, called also mineral tar, is less fluid and less
transparent than naphtha. It has an oily consistence, more or less
viscid. It occurs of a black or brown colour. It burns rapidly,
but not so readily as naphtha, and exhales a black smoke. By
distillation, it forms a liquid like naphtha, and leaves a thick tar
in the retort.

It exudes from rocks, is found in wells, &c. In Pegu, the wells
furnish annually 400,000 hogsheads. It is used there in the place
of oil for lamps. When boiled with rosin, it is used for painting
houses, and the bottoms of vessels. In the embalming of dead bodies,
it was employed by the ancient Egyptians; and, in some countries,
clay, soaked in it, is used as fuel.

It is found in the United States, in Kentucky, Ohio, the western
parts of Pennsylvania, in New York at the Seneca lake, &c. The Seneca
or Genessee oil is the same bitumen.

When petroleum is exposed to the atmosphere, it acquires a greater
degree of consistence, and passes into another bituminous substance,
called maltha. This has the properties, and frequently the appearance
of pitch. When burnt, it yields more smoke and soot than petroleum.
According to its original meaning, it signifies a kind of cement;
and the maltha mentioned by Pliny, Heineccius, Festus, and others,
which was employed in the same manner as our modern sealing wax, was
a mixture of pitch and wax, and was also used to make reservoirs,
pipes, &c. water-tight. Maltha also sometimes resembles wax. Mr.
Kirwan, however, gave it the name of mineral tallow.

Mineral or Barbadoes tar is somewhat thicker than petroleum, and
nearly of the consistence of common tar. It is used for the same
purposes as the ordinary petroleum. Elastic bitumen, a variety
between the softer and harder bitumens, resembles caoutchouc. It
burns with a bright flame, and bituminous odour.

Asphaltum, or solid bitumen, is much harder than pitch, brittle, and
of a brownish-black colour. It burns freely, and leaves but little
residue. In Judea, it is found on the waters of the Dead sea, or the
lake of Asphaltes. It is also called _Jews' pitch_. It was employed
by the Egyptians for embalming under the name of _mumia mineralis_.

Both maltha and asphaltum were used by the ancients as a cement.
The walls of Babylon were cemented with these substances, as
obtained from the river Is, which falls into the Euphrates. It may
be observed, that those countries, which yield bitumen, contain
salt springs, and it frequently accompanies pyrites. Limestone,
particularly the black, contains it, and the colour is often owing
to its presence. The _stink stone_, or bituminous carbonate of
lime, is of this kind. The retinasphaltum, a combination of bitumen
and earth, having a yellow colour, burns with a bright flame, and
fragrant odour, which at last becomes bituminous. Many stones, and
particularly some of the black marbles, owe their colour to bitumen;
hence they burn white. The bituminous schistus, or bituminous shale,
sometimes contains so much of this substance as to burn in the fire.
Jet is a mineral of a black colour, and resembles the cannel coal.
It is inflammable, producing a green flame, with a strong bituminous
odour.

With respect to bitumens, we may observe, that they all possess one
character, that of being inflammable; and that they are more or less
so in proportion as they partake of the principle of naphtha; or, at
least, the rapidity of their combustion depends upon the presence of
this oil. The following additional facts, therefore, with respect to
naphtha, may be interesting: Certain liquids have the property of
uniting with naphtha, which has also the property of dissolving and
combining with solid substances, of which the following examples may
be stated:

At the degree of ebullition, it dissolves sulphur, which, on
cooling, is in part deposited in needle-form crystals. At the same
temperature, it also dissolves phosphorus, part of which is again
separated.

It unites also with iodine. With camphor, it also combines, and in
large quantity. It takes up a much larger proportion of pitch. In the
cold, its action on wax is feeble, but assisted by heat, it unites
with it in all proportions. On lac and copal, its action is feeble.
In the cold, it does not dissolve caoutchouc; but when assisted by
heat, it dissolves this substance, though not completely. These facts
may determine its action in certain mixtures.

According to Theodore de Saussure's Analysis, (_Bibliot.
Universelle_, iv, p. 116), it appears, that naphtha is composed of
87.60 carbon, and 12.78 hydrogen.

_Sec. XIII. Of Oil of Spike._

This oil is principally used as a vehicle for mixing the ingredients
of some kinds of fire-works; and, although it is employed in that
way, yet it has also an effect in combustion, having similar
properties with liquid bitumen. It enters into the composition of
some of the preparations, and perhaps is equally good as liquid
bitumen. Indeed, the oil of spike, as sold in the shops, and
used principally by farriers as an embrocation for horses, is an
artificial preparation, made by mixing together about five ounces of
Barbadoes tar, with a pint of the spirit of turpentine.

_Sec. XIV. Of Amber._

Amber, succinum, karabe, the electron of the ancients, which are
synonimous terms, is very inflammable. A piece of it, put on the
point of a knife, and set on fire, will burn entirely away, emitting,
at the same time, a white smoke, and a somewhat agreeable odour. It
is used in the composition of fire-works, and particularly in some
kinds of rockets. All the preparation it undergoes, when thus used,
is to reduce it to powder in a mortar, and to pass it through a fine
sieve. It also forms a part of the composition of odoriferous fire;
but the formulæ for the latter are various.

Amber is of various colours, either yellowish, white, or
honey-yellow. It is translucent, and sometimes transparent. It may
be turned or polished. It occurs in grains or in irregular masses.
Alluvial deposites of sand, gravel, &c. frequently contain it. It is
also found with bituminous wood, brittle lignite, or jet, and with
other substances. It has been discovered in New-Jersey, near Trenton,
in alluvial soil. Naturalists believe, that amber was once a resinous
juice. Masses weighing 20 lbs. have been found. Sometimes it contains
insects. It is formed into beads and the like. As amber becomes
electric by friction, and the ancients called it electron, the term
electricity is derived from it. By distillation, it yields both an
acid, (the succinic), and an oil. Jet is usually considered black
amber.

We may introduce here a few remarks respecting ambergris:

Ambergris is a substance, which has a peculiar fragrance, and for
that reason is used as a perfume, and may be employed like similar
substances in odoriferous fire. As to its origin, we have no certain
account; but it seems, from its general properties, to be formed in
the same manner as bituminous substances, although it is mostly found
on the sea-shore, where it has been probably washed up from the sea.

Ambergris is found principally on the shores of Ceylon, and is known
to be good, by laying some of it on a very hot knife, when, if pure,
it will not only melt and run like wax, but entirely evaporate,
leaving no residue.

Ambergris, on account of its price, (the retail price in London
being a guinea per ounce), is frequently adulterated with various
mixtures of benzoin, labdanum, meal, &c. scented with musk. But pure
ambergris, when heated, has a greasy feel, and appearance, and is
soluble in hot ether and alcohol.

_Sec. XV. Of Camphor._

Camphor is a resinous substance, although generally called a gum,
which has a peculiar, and powerful smell. It is obtained principally
from the _Laurus Camphora_. It is extracted from this, and other
trees in the East Indies. We are informed, that, in Borneo and
Sumatra, the larger pieces which contain the most camphor, are picked
out with sharp instruments. The Chinese cut off the branches, chop
them small, and place them in spring water. They are then boiled, and
stirred with a stick. As soon as the camphor is observed to adhere to
the stick, the fluid is strained. It is then poured into a basin, and
the camphor separates, in Japan, the roots and the extremities of the
branches are steamed. It is also obtained by sublimation. The roots,
wood, and leaves are all boiled in large iron pots, and the camphor
is collected on straw, placed in a tubular head.

With respect to the refining of crude camphor, in order to produce
_heads_, as they are called, and to free it from impurities, the
operation is nothing more than sublimation. Sublimers made of glass
are used; and into each, the camphor, along with a small portion of
lime, is introduced, and they are then placed in a sand bath. Heat is
applied, and the pure camphor rises and attaches itself to the upper
part of the vessel, forming the refined camphor.

The general properties of camphor are the following: It is not
altered by the atmospheric air, but is volatilized during warm
weather. It is insoluble in water; is soluble in alcohol, forming
the spirit of camphor, and also in volatile and fixed oils. It is
not acted upon by the alkalies. It is dissolved in acids without
effervescence, and by some it is decomposed. Nitric acid converts
it into a peculiar acid, called the camphoric. It melts between 300
and 400 degrees. It takes fire, and burns with a white flame, and,
generally, while it presents the character of a resin, it shows, by
its combustion, like other inflammable bodies, that it contains, in
its composition, a large quantity of carbon and hydrogen.

There are several species of camphor, which have been examined by
chemists and which differ in their properties. These are, common
camphor, the camphor of volatile oils, and the artificial camphor,
formed by treating oil of turpentine with muriatic acid.

The base of camphor forms a constituent part of some volatile oils,
which are in a liquid state; and for its separation, it appears to
require a combination with oxygen.

Camphor may be apparently set on fire by means of water, an
experiment, which is nothing more than producing chemical action by
it, in the following manner: Put a portion of nitrate of copper on
some tin-foil, along with camphor; then by adding some water, and
quickly wrapping the foil up, pressing the edges close, it will
inflame, and sparks of fire be produced.

Camphor has been used in the manufacture of candles. For this
purpose, it is dissolved in brandy, and the wick, composed of
equal parts of cotton and linen, is dipped in. It is then dried,
and covered, in the usual manner, with tallow or wax. The tallow,
recommended as the best for candles, is a combination of equal parts
of mutton and beef suet.

Camphor is very soluble in acetic acid, which is highly inflammable.
This solution is decomposed by water. When combined with essential
oils, it forms aromatic vinegar. Romieu has observed that small
pieces of camphor floating on water have a rotary motion.

Camphor enters into a composition, which is used to determine, like
a barometer, the state of the weather, and the changes it undergoes.
According to the _Journal de Pharmacie_, 1815, some experiments were
made in France on the fluid taken out of one of the English weather
gauges. The liquid contained water and alcohol, was strong with
camphor, and reddened litmus paper. The tube contained 3-1/2 ounces.
On analysis, its contents were found to be, 24 grains of alum, 120
grains of camphor, and enough water to dissolve the former, and
alcohol to dissolve the latter. A similar composition was made, and
put into a tube, which, it seems, had the same effect. The tube is
hermetically sealed. M. Cadet observes, that the _prognosticator_,
made in Paris many years ago, was a similar preparation.

Although, according to Cadet, this contrivance cannot be depended
upon, as the appearances it presents are not regular; yet, as the
effect is produced by heat, as well as light and electricity, the
following summary may be added:

1. In fair weather, the composition remains at the bottom, and the
liquor is clear.

2. Before rain, it will rise a little; the liquor will be clear,
having merely a star floating in it.

3. Before a storm, it will rise to the surface, the liquor will
appear troubled. These appearances may be seen 24 hours before the
change in the weather takes place.

4. In winter, it is higher than common. During a snow, it will be
very white, and pieces are seen in motion.

5. In settled weather in summer, and when warm, the composition will
be low.

6. To know from what quarter wind will come, the composition will
remain attached on the opposite side of the bottle to that from which
it is expected.

Camphor has been burnt, like ether and alcohol, by platinum wire,
previously heated. Dr. Ure observes, that a cylinder of camphor may
be used for both wick and spirit, in the aphlogistic lamp; and the
ignition is very bright, while an odoriferous vapour is exhaled. By
adding various essential oils in small quantities to the alcohol
of the lamp, various _aromas_ may be made to perfume the air of an
apartment. See _Scented Fires for rooms_.

Camphor is employed in those fire-works chiefly, which are exhibited
in rooms; its expense being an objection to its use in large
exhibitions. In what are termed perfumed pastes, or mixtures, scented
fire, or odoriferous fire-works, it is used in abundance: in fact,
it enters into nearly all the compositions of this kind. Camphor,
besides producing, alone, a white flame, gives a brilliant light,
and, when mixed with other substances, adds greatly to the appearance
of the flame; and, giving out a powerful odour, destroys, in a
measure, the disagreeable smell arising from the combustion of the
sulphur and nitre.

By referring to the article on Greek fire, and some incendiary
preparations used in war, it will be seen, that camphor is an
important constituent. As camphor is very combustible, and will
even burn on the surface of water, it is well adapted for all those
purposes. We have already spoken of the Greek fire; and it seems,
that the peculiar character of that fire, of burning in water, was
owing to the presence of camphor. This opinion appears plausible,
when we consider, that some preparations _have been_ made with
camphor, which had the property of burning on water.

Camphor may be pulverized by the assistance of, and brought into
intimate mixture with, nitre and sulphur; because the former, in
particular, tends to divide it. But it may be pulverized separately,
and afterwards added to the composition, by rubbing it in a mortar
with a small quantity of alcohol, or spirit of wine; or, if this
cannot be had, with fourth proof brandy. As camphor is very
inflammable, its effects, when mixed with saltpetre and fired, are
much the same as those produced by other resins, or concrete oils.
A combustion, more or less rapid, ensues, and, while the nitre
itself is decomposed, the camphor also undergoes the same change,
producing both water and carbonic acid, from the union of two of its
elements, the hydrogen and carbon, with the oxygen of the nitric
acid. In all cases, in which camphor is employed in artificial
fire-works, although its own flame is _white_, it may assist in
increasing the flame, which, however, is modified, according to the
substances, which enter into the composition. These may not retard
its combustion, but, nevertheless, may change the appearance of the
flame; as is the case, when we employ the filings of iron, steel,
brass, or zinc, sal ammoniac, rosin, saw-dust, and other substances,
which usually form a part of such mixtures. Upon the whole, then, we
may consider, that camphor acts in fire-works; 1st, as an inflammable
body; 2ndly, that, besides being in a great measure decomposed, a
portion of it is evaporated, and communicates, to the surrounding
atmosphere, a peculiar smell, which is recognised in the odoriferous
fire-works; 3rdly, that, while it acts in taking a part of the oxygen
from the nitric acid of the nitre, it assists in the decomposition
of this salt, more especially if it be mixed separately with the
nitre; 4thly, that, in all instances of its combustion, while it
acts primarily on the nitre, with the oxygen of which it forms both
water and carbonic acid, it, at the same time, increases the flame,
which may be either white, red, or yellow, according to the other
substances employed; and, finally, it may be thrown out in the
state of combustion, and receive, for the further support of its
combustion, the oxygen of the air, and hence produce a white exterior
flame, while that in the immediate vicinity of the composition may
be more or less coloured. But its application, the proportions in
which it is used, as well as the kind of fire-works to which it is
applicable, will be considered at large in other parts of the work.

The great inflammability of camphor is to be ascribed to its
containing a _large_ quantity of carbon and hydrogen, and a _small_
quantity of oxygen.

There is a preparation, called artificial camphor, that is formed by
passing muriatic acid gas through spirit of turpentine. It inflames
with facility, and burns, without leaving any residue. Might not
this preparation be economically employed, in lieu of camphor, for
incendiary fire-works?

_Sect. XVI. Of Gum Benzoin, and Benzoic acid._

Gum Benzoin, or Benjamin, is considered a solid balsam, and is the
production of a tree, which grows in Sumatra, &c. called the _styrax
benzoe_. It is obtained from this tree by incision, a tree yielding
three or four pounds. It is a brittle substance, sometimes in the
form of yellowish-white tears and called, from that circumstance,
almond benzoin. Besides a resinous substance, it contains an acid,
called the benzoic or _flowers of benzoin_, a substance similar to
balsam of Peru, being a peculiar aromatic principle, soluble in
alcohol and water. By heating it, or by combustion, it evolves a very
agreeable smell, and is, therefore, used in those fire-works which
are exhibited in rooms, theatres, &c. and also in the composition
of odoriferous fire-works. Besides being in itself inflammable, it
produces a peculiar smell, arising, in all probability, from an
essential oil, aided, in some degree, by the separation of benzoic
acid.

It has been examined by Bucholz and Brande. Its general properties
are: that it is insoluble in water, although hot water takes up a
part of it, said to be the benzoic acid. It is soluble in alcohol,
from which it is separated by muriatic and acetic acids, but not by
the alkalies. It is also soluble in ether.

The benzoic acid, or flowers of benzoin, are obtained from it by
sublimation. A quantity of the powdered gum, put into an earthen
basin, a thick paper cone being tied round the rim, and heat applied,
the acid will leave the resin, and be condensed on the inner side
of the cone. Bucholz (_Bulletin de Pharmacie_, v. p. 177) has given
a process for obtaining it by means of alcohol, and some others
have been adopted. By boiling four ounces of the gum in powder in
a sufficient quantity of water, with three drachms of carbonate of
soda, the acid will unite with the alkali, and form a benzoate of
soda, which, when filtered and decomposed by sulphuric acid, will
yield the benzoic acid. Five drachms of acid will be thus obtained.
Lime has been used in the same manner as soda, and the acid separated
by the addition of muriatic acid.

Flowers of benzoin may be used in the place of the gum; using,
however, but a small quantity. They will communicate the same odour
to fire as the benzoin. The flowers, or acid of benzoin, are so
inflammable, as to burn, with a clear yellow flame, without the
assistance of a wick. It is soluble in ardent spirits, in oils, and
in melted tallow. The compounds, which it forms with them, are also
inflammable. Benzoic acid is considered to be an oily acid, and
contains, no doubt, a very large proportion of hydrogen.

_Sect. XVII. Of Storax Calamite._

Storax is the most fragrant of all the balsams. It is afforded by
the _styrax officinalis_, a tree which grows in the Levant. It is
sometimes in red tears. Common storax is in large cakes, and brittle
and soft to the touch. This is more fragrant than the other sort,
but is frequently adulterated with saw-dust. It is soluble in
alcohol, and is said to yield some benzoic acid.

Styrax is a different substance; a semi-liquid juice obtained from
the _liquidambar styraciflua_. Its odour is less agreeable than that
of storax calamite. It is used in odoriferous fire, in _pastes_, in
the composition for _scented vases_, and the like.

_Sect. XVIII. Of Essential Oils._

Essential or volatile oils, as well as the raspings of red cedar,
dried rosemary, and other fragrant plants, are all used in the
preparation of odoriferous fire. In some preparations, the _oil of
roses_ is employed; in others, the essence of bergamot, of lemon,
&c. which, being very volatile, evaporate in a moderate heat, and,
being also inflammable, may assist in the combustion. In the case of
the raspings of cedar in particular, it also communicates a peculiar
appearance to the flame.

Oils, whether essential or fixed, when passed through ignited tubes,
are decomposed, and furnish an inflammable gas called olefiant gas.
Wax, tallow, &c. produce the same gas, the hydroguret of carbon.
Messrs. Taylor and Martineau contrived an ingenious apparatus for
generating gas from oil on the great scale, as a substitute for
candles, lamps, and coal gas, it being much preferable for burning,
as it contains no sulphur, and does not injure furniture, books,
plate, paint, &c. Oil gas contains more hydroguret of carbon than
coal gas, which is a great advantage, enabling one cubic foot of
oil gas to go as far as four of coal gas. An elegant apparatus was
erected by Taylor and Martineau at the Apothecaries' Hall, London, a
drawing of which may be seen in the 15th number of the "_Journal of
Science and the Arts_."

It is to be observed, that odoriferous fire-works are intended for
exhibition in close apartments; so that the smell of certain gases,
produced by the nitre, charcoal, and sulphur, according to the
preparation used, will be more or less destroyed. Such preparations
are, nevertheless, expensive, and for that reason seldom used.

_Sect. XIX. Of Mastich._

This resin, obtained, from the _pistacia lentiscus_, by making
transverse incisions in the tree, is first in a fluid state, and
gradually concretes into yellowish semi-transparent brittle grains.
In Turkey, great quantities of it are used for sweetening the
breath, and strengthening the gums. It is from the use of the resin
as a _masticatory_, that its name is said to be derived. It is not
completely soluble in alcohol, a soft elastic substance separating
from the solution. When exposed to heat, it melts, and exhales a
fragrant odour: for which reason, principally, it enters into the
composition of some fire-works, as the _scented paste_. In ordinary
fumigations, mastich is commonly used.

_Sect. XX. Of Copal._

Gum copal, by which name it is known, is a resin, obtained from
a tree, called _thus copallinum_. It is often in the form of a
beautiful white resin; but sometimes it is more or less coloured.
It is frequently opaque. It may be dissolved in alcohol, spirit of
turpentine, and oils, by a peculiar management, (by using camphor,
previously melting it, and the like,) and then it forms the various
copal varnishes, which are more or less perfect, as the copal is
transparent, and the solution properly formed. When heated, it
melts like other resins, and in this, and many other properties, it
partakes of the character of resins in general. It is used in some of
the formulæ for fire-works.

_Sect. XXI. Of Myrrh._

Myrrh is obtained from a plant, supposed to belong to the genus
_mimosa_, which, as Bruce informs us, (_Travels, &c._) grows in
Abyssinia and Arabia. It is in the form of tears, of a reddish-yellow
colour; sometimes transparent, and at other times opaque. It
possesses a peculiar odour, and a bitter and aromatic taste. It burns
with difficulty, and does not melt when heated. With water, it forms
a yellow opaque mixture. It dissolves in alcohol, and the solution
is decomposed by the addition of water, the whole becoming opaque.
According to Braconnot, myrrh is composed of 23 resin, and 77 gum, in
the 100 parts. Pelletier, whose analysis differs from Braconnot's,
observes, that, besides resin, it contains some volatile oil, to
which, no doubt, its fragrance is owing. The gum, extracted from
it, had the character common to all gums, with the exception, that,
instead of forming the mucous or saclactic acid, by the action of
nitric acid, it produced only oxalic acid.

That myrrh burns with difficulty, is owing entirely to the presence
of so much gum, and, comparatively speaking, the small quantity
of resin, which enters into its composition. But, notwithstanding
this property, as it partakes of a fragrant oil, it is used in
some compositions for fire-works. The gummy part may retard, as is
sometimes required in particular preparations, the rapidity of the
combustion, and therefore have a two-fold effect when employed in
fire-works.

_Sect. XXII. Of Sugar._

Refined sugar is sometimes used in pyrotechno-mixtures. As it is a
vegetable oxide, (composed of carbon, hydrogen, and oxygen), which
is decomposed by heat, and has the property of decomposing nitric
acid, and some of its combinations; its operation in such mixtures
may be readily perceived. We have seen, when treating of chlorate
of potassa, that, when this salt and sugar are mixed together, and
sulphuric acid poured on the mixture, a rapid combustion ensues,
which is owing as well to the decomposition of the sugar, as to
that of the salt. The matches, likewise, which inflame by immersion
in sulphuric acid, are covered with a similar mixture. That sugar,
therefore, has the property of decomposing those salts, which are
composed of acids, that have their oxygen but feebly combined,
and thereby producing combustion, according to the temperature
employed, or other agents made use of, is evident from a variety
of experiments. By its action, then, in such cases, the products
of combustion, arising from the elementary parts of the sugar
alone, uniting with oxygen, must be carbonic acid and water. Sugar,
submitted to destructive distillation, affords a variety of new
substances; among which we may notice _caromel_, or that peculiar
odour, which is recognised in the burning of sugar. Sugar may,
therefore, besides assisting in part in the decomposition of saline
bodies, and particularly nitre, and perhaps giving rise to new
products, with which we are unacquainted, have another effect, that
of destroying the offensive smell of other substances, by means of
the caromel formed. Sugar, also, when mixed with various bodies, and
struck with a hammer, will produce detonations.

Sugar, when used in compositions of fire, should be pure; and it may
be known to be so, by producing invariably a phosphorescence in the
dark, when two pieces are rubbed together. At a red heat, it bursts
into flame with a kind of explosion. This flame is white, with blue
edges.

Sugar is obtained from the sugar-cane; from the sap of the
sugar-maple; from beets and grapes; and from various other saccharine
bodies. It is formed also artificially, by the action of sulphuric
acid on starch.

Mr. Kirchoff, a Russian chemist, accidentally discovered that starch
may be changed into sugar by diluted sulphuric acid. One hundred
parts of starch yield one hundred and ten of sugar. It appears, that,
by the abstraction of a little hydrogen and carbon, starch will be
converted into sugar. Potatoes, digested with diluted sulphuric
acid, Dr. Ure found, would also form sugar, and very abundantly.
The sulphuric acid may be removed by the addition of chalk, and, as
the sulphate of lime is but slightly soluble, the pure saccharine
fluid may be obtained by filtration. The sugar is procured in a
solid state by evaporation, and may be clarified like other sugar.
Dr. Ure observes, that good beer has been made from starch-sugar,
but recommends potato-sugar. To obtain the latter, the potatoes are
washed, grated down, and treated with the dilute acid for a day or
two, at a temperature of 212°.

The observations of Braconnot are interesting. He has succeeded in
converting a variety of vegetable substances into gum and sugar. The
conversion of wood into sugar, however remarkable it may seem, has
been effected; and a pound weight of rags will, by the same process,
make more than a pound weight of sugar. Rice, as it contains a large
quantity of fecula, may, we have no doubt, be converted, in the same
manner, into saccharine matter.

When sugar is first obtained, it is impure, containing a variety
of foreign substances, and more or less brown, as the Muscovado of
the West India islands. It is refined, and formed into loaves, by
treating its solution in water with bullocks' blood, the serum of
which coagulates by heat; and, finally, by pouring the sugar, when
sufficiently boiled, into conical earthen moulds, where it concretes.
It is clayed, by putting a mixture of white clay and water on the
sugar in each of the cones; the water from which passes through, and
renders it beautifully white. The same process may be repeated; hence
the single and double refined sugar. The molasses passes out from the
sugar at the apex of the cone, and is received in vessels.

From twenty to thirty-five per cent. of molasses are separated in the
refining of raw sugars; and it is supposed, that a considerable part
of it, probably two-thirds, are formed by the high heat used in the
concentration of the sirup. In order to prevent so great a quantity
of molasses, different plans have been recommended. That of Howard
is highly spoken of. It consists in surrounding the sugar-boiler
with oil or steam at a high temperature, instead of exposing it,
as heretofore, or the mode usually adopted, to the naked fire. The
boiler is covered at top, and, by means of an air-pump, the air
is exhausted, and the pressure of the atmosphere being removed,
ebullition takes place at a lower temperature. No blood is used in
Mr. H.'s process, instead of which, the clarification is performed by
means of canvass filters, adding previously a pasty mixture of gypsum
and alumina, made by saturating a solution of alum with quicklime.
He does not employ clay, as is done in whitening the sugar; but,
in its place, makes use of very pure saturated sirup. He uses
animal charcoal, (bone black), which has the property of destroying
vegetable colouring matter. Wilson's process for refining sugar
possesses some advantages. It will be found in the 34th volume of the
_Repertory of Arts_. The patent filtering apparatus of Sutherland is
highly approved.

The chemical properties of sugar are the following: It is very
soluble in water, both hot and cold; it forms with water a sirup,
which on standing will crystallize, forming the candied sugar. It
is not acted upon by oxygen gas. It is capable of combining with,
and, according to some chemists, of neutralizing acids and alkalies.
It is decomposed by nitric acid with effervescence, being converted
into oxalic and malic acids. Tartaric, acetic, and oxalic acids
prevent it from crystallizing. It unites with lime and strontian,
but is partially decomposed by barytes. It combines also with oxide
of lead, which it precipitates from its solution, forming, as it
is called, a saccharate of lead. Alcohol has some action on it,
and also hydrosulphurets, sulphurets, and phosphurets of alkalies
and alkaline earths. On the application of heat, it melts, swells,
becomes brownish-black, and exhales a peculiar odour, which we have
mentioned, and, at a red heat, takes fire. Lastly, though possessed
of some general and specific characters, it differs, in some of its
properties, according to the substance from which it is obtained.

_Sect. XXIII. Of Sal Prunelle._

This salt is nothing more than nitrate of potassa, melted in a
crucible, and poured into moulds, whence it receives the form under
which it is found in the shops. The saltpetre, when merely fused,
is not decomposed, as it is when exposed to a red heat in an iron
retort. In the former case, the water only which it contains is
separated; but, in the latter, the salt itself is decomposed, and
oxygen gas evolved. Sal prunelle, therefore, is fused saltpetre.
Combustible bodies, as charcoal, sulphur, phosphorus, oils,
resins, &c. have the same effect on it as on ordinary nitre. The
only advantage it has over the common refined saltpetre, in the
preparation of some fire-works, is, that it is free from water, and
more readily acted on by combustible substances. In preparing it,
care must be taken in the application of the heat; which, if too
powerful, would, besides fusing it, decompose, and convert it into
nitrite of potassa. It may be readily pulverized and sifted. For the
properties of _nitre_, see that article.

_Sect. XXIV. Of Alcohol._

Alcohol, or rectified spirit of wine, is used for a variety of
purposes in pyrotechny, and, when it cannot be procured, strong
brandy is substituted. In assisting the pulverization of some
substances, as camphor, in forming the mixture of certain pastes, and
in acting as a vehicle for the intimate union of some bodies, it is
considered a necessary article. Alcohol may be made to form variously
coloured flames, by mixing with it certain saline substances. Thus,
boracic acid will form a green flame; muriate of strontian, a carmine
red; muriate of lime, an orange; nitrate of copper, an emerald
green; nitre, common salt, and corrosive sublimate, a yellow, &c. As
alcohol has the property of dissolving essential oils, camphor, &c.
it may be used as a menstruum for certain oils in the preparation
of odoriferous fire-works. See _Articles on coloured flame, and
odoriferous fire_.

Alcohol constitutes a part of all ardent spirits, wine, cider,
beer, &c. in which it is combined with water, or with water and
mucilaginous and colouring matter. It is formed in the vinous
fermentation, and always results from the union of carbon and
hydrogen. During the process, carbonic acid gas is liberated.
Fermented liquors, therefore, or those which have passed through
the vinous fermentation, always contain alcohol in more or less
abundance, but mixed with water in many instances. In some it is
accompanied with water, and saccharine, mucilaginous, and extractive
matter. The different kinds of beer is an example of this fact.
When liquors, which contain spirit, are submitted to distillation,
the product is alcohol and water; for the volatile parts evaporate,
and the fixed substances remain in the still. The spirit partakes,
more or less, of a peculiar taste and flavour, by which liquors are
distinguished from each other. On this subject, however, it will be
sufficient to add, that brandy is procured by the distillation of
wine; rum, from the fermented juice of the sugar-cane; gin, from
fermented grain and juniper-berry; whiskey, from the fermented mash
of grain, cider, &c. and, generally, the ardent liquors, from pears,
peaches, and other substances, by the same process.

Alcohol, therefore, exists in all these distilled liquors, in a
greater or smaller quantity, combined with water; and the proportion
it bears to the water is known by a standard, as either proof, above
proof, or under proof, according as its strength is shown by the
hydrometer.

The process of obtaining alcohol in a pure state, (usually called
rectified spirit of wine), by which the water is separated from the
alcohol, consists in repeated distillations, either alone, or mixed
with certain substances, which have the property of uniting with, and
keeping down the water, in the act of distillation. These substances
are usually potash, and dry muriate of lime, both of which substances
have a great affinity for water. The specific gravity of highly
concentrated alcohol, at 60° is .820, but that of common alcohol,
only .837, at the same temperature.

The properties of alcohol are the following: It is a transparent
liquor of an agreeable flavour, and may be changed in this
particular, by essential oils. It may be exposed to a low temperature
without freezing. It boils at 106°, when of the specific gravity
.820, and in a vacuum at 56°. It has a strong affinity for water,
with which it combines in any proportion; and the specific
gravity varies according to the proportion of the mixture and the
temperature, on which are founded the tables of Blagden, Gilpin, and
others.

Neither common air, nor oxygen, has any action on alcohol at moderate
temperatures, whether in a liquid or aeriform state. On hydrogen,
carbon, and charcoal, it has little or no action, but on phosphorus
it acts, a portion of which it dissolves. With sulphur, it may be
made to unite, as also with the alkalies, but not with the earths,
except strontian and barytes. It is decomposed by sulphuric and
nitric acids, with both of which it forms ether. It dissolves some
salts, and has scarcely any effect upon others. Lastly, it dissolves
resins and essential oils; but it neither acts upon gums, properly so
called, nor on fixed oils. It is a compound of hydrogen, carbon, and
a small proportion of oxygen, and may be decomposed, by passing its
vapour through an ignited porcelain tube.

Alcohol, by its combustion, as it is used in spirit-lamps for
chemical and other purposes, produces no smoke, in consequence of
the carbon it contains being totally converted, during that process,
into carbonic acid; and its hydrogen, uniting with another portion of
the oxygen of the atmospheric air, passes off in the form of aqueous
vapour. Alcohol, used in this way, is preferable to oil; for the
latter produces a large quantity of smoke, unless it is burnt in the
Argand lamp. Alcohol is inflamed, when it is brought in contact with
an ignited body. The combustion is rapid without any residue, and the
flame white.

As to the strength of alcohol, the best means of determining it, is
with the hydrometer; but usually its _proof_ is ascertained by means
of gunpowder. A portion of powder, put into a cup, and alcohol poured
on it and inflamed, will, if the latter be strong, be set on fire;
if, however, the powder should not take fire, but the flame of the
alcohol be extinguished, we infer the existence of water, and that
the alcohol is not of the proper strength. This experiment is founded
on this circumstance, that, if the alcohol contains water, after the
alcoholic portion is all consumed, the water will not only extinguish
the flame, but also prevent the inflammation of the powder. The
hydrometer, however, is the best experiment, as it determines at once
the fact of the _strength_ of the liquor.

Alcohol is used in the preparation of certain fulminating substances,
as fulminating mercury and silver in particular; the preparation of
which, we will give in the two next sections.

It may not be improper to mention another application of alcohol,
that of forming the _aphlogistic lamp_, or lamp that burns without
flame. The following description of it, is given by Accum, in his
_Chemical Amusements_, Am. Ed. p. 355. "In a common lamp, with a
wick of about half a dozen common threads of cotton wick, used for
lamps, put some good spirit of wine. Dispose the threads of wick, not
intertwined, but straight and parallel to each other. Take platina
wire of the thickness of 1/100th part of an inch; coil it round the
wick, about nine coils below, and six coils standing above the top
of the wick; the diameter or width of the coils should not be more
than 3/20th, or 1/7th of an inch wide. Light the wick; and, when the
coil of platina above the wick is red-hot, blow out the flame. There
will then be a current of pure alcohol, gradually rising from the
reservoir below, through the wick, sufficient to keep the upper coil
of platina red-hot, until the whole of the alcohol is consumed. This
lamp has kept constantly lighted during sixty hours. By means of
it, a match, a bit of spunk, or candle may be lighted when wanted.
The quantity of alcohol consumed is not much: about an ounce, or an
ounce and a half during the night, from bed-time until morning will
suffice." This article was added to Accum by Dr. Cooper. A figure
of the lamp is in Brande's Chemistry. Dr. Comstock has a paper on
the aphlogistic or flameless lamp, in Vol. IV. p. 328, of Silliman's
_Journal of Science and Arts_, which contains some judicious and
useful remarks. Sir H. Davy (_Journal of the Royal Institution_) has
discovered, that the vapour of camphor answers the same purpose as
alcohol. If a platinum wire be heated and laid upon camphor, it will
continue to glow as long as any remains, and the wire will frequently
light it up into flame. Davy found, that, in the slow combustion of
alcohol, &c. an acid was generated, to which he gave the name of
Lampic acid. Faraday and Daniel (_Journal of Science and the Arts_)
have confirmed his conclusions.

Dr. Marcet has proposed a method of producing an intense heat, by
causing a current of oxygen gas to pass through the flame of alcohol.
The construction of the lamp and gas-holder may be found in the
_Archives des Découvertes_, Vol. vii, p. 61.

_Sect. XXV. Of Fulminating Mercury._

As the fulminating mercury of Howard consists principally of the
oxalate of mercury, the oxalate of this metal may be employed for the
same purpose. Oxalic acid does not act on mercury, but dissolves its
oxide, and forms with it a white powder. I formed various fulminating
metallic powders, (_See Coxe's Medical Museum_), and prepared one
in particular by merely digesting a solution of the salt of sorrel
(superoxalate of potassa) on red precipitate. The effect is that the
oxalic acid unites with the oxide of mercury, and forms an oxalate
of mercury, which, when struck with a hammer, produces a detonation.
Oxalate of mercury, possessing the same effects, may be formed, very
expeditiously, by pouring the oxalate, or the superoxalate of potassa
into a solution of nitrate of mercury. The oxalate of mercury will be
precipitated, which is to be caught on a filter, washed, and dried in
a gentle heat.

Howard's fulminating mercury is less dangerous than either
fulminating silver, or fulminating gold. The extreme force of
detonation which it possesses is remarkable. The temperature
required for its explosion is 360 degrees. Friction, percussion,
electricity, and the flint and steel will produce this effect. It
gives rise to a stunning disagreeable report, and its force is
sufficient to indent both the hammer and the anvil. Four or six
grains are sufficient for an experiment. It is rather singular, as
Mr. Cruikshank first observed, that this powder will not inflame
gunpowder; as may be shown by spreading some of the former on paper,
and shaking gunpowder over it, and then firing the mercurial powder.
The grains of the gunpowder may be collected entire after the
explosion.

From the experiments of Howard, it appears, that this powder is
composed of oxalate of mercury, and nitrous etherised gas. Fourcroy,
however, has shown, that it varies in its nature, according to the
mode of its preparation.

There is also a preparation of mercury, which is likewise explosive,
discovered by Fourcroy. This compound may be formed by digesting
the red oxide of mercury in liquid ammonia for the space of eight
or ten days. The oxide assumes a white colour, and at last appears
in crystalline scales. Upon ignited coals, it detonates loudly like
fulminating gold, which see below. In a few days, however, it loses
its fulminating property, and undergoes spontaneous decomposition.
Exposed to a low heat, the ammonia is disengaged, and an oxide of
mercury remains.

As ammonia forms several detonating compounds with metallic oxides,
the theory of their explosive effects is the same; viz. that, while
the hydrogen of the ammonia unites with the oxygen of the oxide,
forming water, the azote is disengaged in the state of gas.

The process for preparing Howard's fulminating mercury is the
following, dissolve one hundred grains of mercury in an ounce and a
half (by measure) of common nitric acid, assisting the solution by
heat. When cold, pour the solution upon two ounces (by measure) of
strong alcohol, and apply a moderate heat, until the mixture begins
to effervesce. A white fume then begins to undulate on the surface of
the liquor, and a white powder precipitates, which is the fulminating
mercury. This powder is to be immediately washed with cold water,
and dried at a heat, not much exceeding that of boiling water. One
hundred grains of mercury, will give, on an average, one hundred and
twenty-five grains of the powder.

The products of its combustion are carbonic acid gas, azotic gas,
water, and mercury. Besides by percussion, it is inflammable when
brought in contact with sulphuric acid. It is supposed, that
fulminating mercury sometimes contains ammonia, and that the products
of combustion, according to the mode of preparation, are therefore
different. The reader may consult some interesting observations on
this powder in the _Journal de l'Ecole Polytechnique_.

M. Bayen, an apothecary, in 1779, (_Journal de Physique_), announced
a process for preparing fulminating mercury. His process, however,
is different from that described. A solution of mercury is made in
nitric acid, and precipitated by caustic alkali. The precipitate
(oxide of mercury) is then caught on a filter, washed, and dried.
Thirty grains of this powder, mixed with four or five grains of
sulphur, and struck with a heavy hammer, or heated on an iron, will
explode with violence. The oxide of mercury, obtained from its
solution by lime-water, has the same effect, when treated in the same
manner. Another process recommended is, to precipitate a solution of
the perchloride of mercury (corrosive sublimate) by lime-water, and
treat the precipitate with sulphur, as above described.

_Sect. XXVI. Of Fulminating Silver._

This compound, which is more powerful than fulminating mercury, is
prepared also with alcohol. Descostils (_Annales de Chimie_, LXII. p.
198,) Cruikshank, and Brugnatelli, have all written upon it.

Fulminating silver explodes without much heat. By the slightest
friction it is inflamed, and detonation follows. Hence it is used in
the form of toys, in fulminating balls, bombs, crackers, &c. which
explode by falling on the ground. Torpedoes, pulling crackers, &c.
are formed of this powder. The fulminating balls are made of glass,
and contain a grain or two of fulminating silver, mixed with sand.
The same mixture, put on the ends of two strips of paper, and the
ends pasted, forms the pulling crackers; for the moment they are
pulled asunder, the friction produced sets the fulminating silver on
fire, and causes a detonation.

The same preparation placed on a wafer, and the wafer put between
paper, as in the sealing of a letter, will explode, when the paper
or the wafer is broken. Fulminating bombs are balls of the size of a
hazle nut, containing about three grains of the fulminating silver.
Their explosive effects are said to be violent. See _Detonating
Works_.

This powder, in consequence of its powerful action, is dangerous;
and, as it explodes so readily, it should never be put into a phial,
nor should it be touched or handled in any way that can produce
friction. Even when made to approach the flame of a candle, it will
explode with extreme violence.

The preparation of Brugnatelli's fulminating silver consists in
reducing 100 grains of nitrate of silver (lunar caustic) to powder;
and, when put into a basin, pouring over it one ounce of alcohol,
and the same quantity of nitric acid. The mixture will become hot,
effervescence will ensue, while the whole will assume an opaque or
milky appearance.

When the gray powder of the nitrate has become white, and the mixture
acquires consistency, distilled water is to be added, to suspend
the action. The white precipitate is then to be washed by repeated
affusions of cold water, and dried in the open air, but in a dark
place, so as to seclude it from the light.

In fact, this process is similar to that for preparing fulminating
mercury; for it is nothing more than treating silver with nitric acid
and alcohol. Cruikshank employs forty parts of silver, sixty parts of
nitric acid, and sixty parts of alcohol, from which sixty parts of
the powder are obtained.

Berthollet considers this powder to be composed of ammonia, and oxide
of silver, and the theory of its detonation to be the same as that
of fulminating gold. In its explosion, the oxygen of the oxide of
silver unites with the hydrogen of the ammonia, and the nitrogen is
disengaged.

Berthollet's fulminating silver, which he discovered in 1788, is
another preparation, which fulminates powerfully. It is prepared by
precipitating nitrate of silver by lime-water. The precipitate is
placed on filtering paper, which absorbs the water, and the nitrate
of lime. Pure caustic ammonia is then added, which produces an effect
somewhat similar to that attending the slaking of lime. The ammonia
dissolves only a part of this precipitate. It is left at rest for ten
or twelve hours, and at the expiration of this time, there is formed,
on the surface, a shining pellicle, which is re-dissolved with a
new portion of ammonia, but which does not appear, if a sufficient
quantity of ammonia has been added at the first. The liquid is then
separated, and the black precipitate, found at the bottom, is put, in
small quantities, on separate papers. This powder explodes even when
moist, if struck with a hard body. When dry, the slightest friction
will explode it. Its detonation is owing to the same cause as that
producing the explosion of the other preparation of this metal, as it
is also composed of oxide of silver and ammonia.

The fulminating silver of Chenevix explodes only by a slight
friction in contact with combustible substances. It is nothing more
than chlorate of silver. It is formed by passing chlorine gas through
alumina, diffused in water, and afterwards digesting, in the liquor,
some phosphate of silver. The whole is to be evaporated slowly. A
single grain of this powder, with three grains of sulphur, will
explode by the slightest friction.

For the preparation of fulminating silver, the formula given
by professor Silliman of Yale College, appears to possess some
advantages. To an ounce of alcohol and as much nitric acid, he adds
100 grains of pulverized lunar caustic. A gentle heat is applied to
excite the action between them, which must be removed, the moment
they begin to act. When a thick white precipitate appears, cold water
must be added to check the action. The precipitate is then to be
collected, washed, and carefully dried. A grain or two will explode
over a candle.

_Sect. XXVII. Of Fulminating Gold._

The preparation, called by some aurate of ammonia, is formed by
dissolving gold in nitromuriatic acid, diluting the solution with
water, and adding gradually liquid ammonia, until the precipitation
ceases. The precipitate is then to be caught on a filter, well
washed with water, and dried in the air. The fulminating gold,
thus produced, exceeds the weight of the original gold employed by
thirty-three per cent.

Three or four grains of this powder, heated on a knife, will explode
with a loud report. The temperature required for its explosion
is between 230° and 300°. Ten or twelve grains will penetrate a
copper-plate, of the thickness of a playing card. The facility with
which this powder explodes, is increased by drying. If it be heated
until it becomes black, the slightest touch will cause a detonation.
This powder is composed of oxide of gold, ammonia, and a portion of
chlorine; and, during its detonation, water, nitrogen and chlorine
are evolved, the gold being revived.

The presence of ammonia is necessary to give to gold the property of
fulminating. Fulminating gold accordingly loses this property, the
moment the ammonia is separated. Concentrated sulphuric acid, melted
sulphur, fat oils, and ether have this effect.

The discoverer of fulminating gold was a German Benedictine Monk,
who lived about the year 1413. Basil Valentine has described the
preparation of it very accurately. He recommends, however, mixing
sal ammoniac with aqua fortis, the old mode of making aqua regia,
and distilling the mixture; then putting in the gold in leaf. After
the acid is saturated, he adds _oleum tartari_, or _sal tartari_
(carbonate of potassa) dissolved in water; and the precipitated
_calx_, thus obtained, when collected, washed, and dried in the
open air, will fulminate. In this process, it is evident, that the
aqua regia, prepared with sal ammoniac, contains ammonia, and, when
the gold is dissolved, and the potash added, the oxide of gold
separates, and, from the composition of the powder, must combine with
a portion of ammonia, and hence produce fulminating gold. He remarks,
that distilled vinegar digested on fulminating gold, destroys its
fulminating properties, and observes also, that care must be taken to
prevent its explosion. He also knew that sulphur would have the same
effect.

Bergman (_Treatise on Pulvis Fulminans_) describes the process
employed by Valentine; and Beckman (_History of Inventions_, v. iii.
p. 132,) observes, that, after the time of Valentine, Crollius, who
lived in the last half of the 16th century, was well acquainted with
fulminating gold, and made its preparation more generally known.
In the _Oswaldi Crollii Basilica Chymica_, 4to, p. 211, published
at Frankfort, in 1609, the process is also to be found. He calls
it _aurum volatile_, and speaks of its being useful in medicine.
Beguin, however, appears to have given it the appellation of _aurum
fulminans_, if we judge from his _Tyrocinium Chymicum_, 12mo, printed
in 1608.

_Sect. XXVIII. Of Fulminating Platinum._

While noticing explosive compounds, it may not be improper to mention
that of platinum, lately discovered by Mr. E. Davy. It explodes,
when heated to 400 degrees, with a sharp report, similar to that
produced by fulminating gold; but neither friction nor percussion
will decompose it. It is formed by making a solution of platinum in
nitromuriatic acid, and passing through it, sulphuretted hydrogen
gas, until no further precipitation ensues. This precipitate, when
collected, and digested in nitric acid, is converted into sulphate of
platinum. This is dissolved in water, and liquid ammonia then added.
The precipitate, now formed, is washed, and boiled in a solution of
potassa, and, after having freed it from the adhering potassa, is
suffered to dry. All fulminating ammoniacal compounds are analogous;
and fulminating platinum, being composed of oxide of platinum,
ammonia, and water, is decomposed in the same manner as these
compounds.

Fulminating platinum is composed as follows:

Peroxide of platinum 82.5 _nearly_ 2 primes.
Ammonia 9.0 1 ----
Water 8.5 2 ----

_Sect. XXIX. Of Detonating Powder from Indigo._

That indigo produces a detonating powder by treating it with nitric
acid, is evident from experiment. As it produces a _purple_ light, it
might, perhaps, be used advantageously in small fire-works.

The process described by Dr. Thomson, (_System of Chemistry_, VOL.
IV. p. 80, _Amer. edit._) is to boil one part of indigo in four parts
of nitric acid. The solution will become yellow, and a resinous
matter appear upon its surface. The boiling is to be stopt, and the
liquor cooled. The resinous matter is then to be separated; and
the solution evaporated to the consistence of honey. This is to be
re-dissolved in hot water, and filtered, and a solution of potassa
added, which will throw down yellow spicular crystals, consisting of
_bitter principle_, combined with potassa. When the resin is again
treated with nitric acid, the same bitter principle is produced.
The spicular crystals, when wrapped up in paper, and struck with a
hammer, detonate with a purple light.

_Sect. XXX. Of the Fulminating Compound, called Iodide of Azote._

Iodine is a particular substance, which has the property not only
of combining with oxygen and hydrogen, forming iodic and hydriodic
acid, but also with various bases constituting a class of bodies,
called iodides. Its union with azote produces a singular substance,
which detonates with great violence, when slightly touched or heated.
It may be formed, by putting a quantity of iodine into the water of
ammonia. It will be gradually converted into a brownish-black matter,
which is the iodide of azote. It is formed in this process by the
iodine, in the first instance, decomposing a part of the ammonia; the
hydrogen of which combines with a portion of the iodine, and produces
hydriodic acid, which then unites with the undecomposed part of the
ammonia, and forms the hydriodate of ammonia; whilst the azote the
other constituent of the ammonia, unites with another portion of the
iodine, and forms the compound in question.

When exposed to the air, iodide of azote gradually flies off in
vapour, without leaving any residue. The products of its detonation
are iodine and azotic gas.

The iodide of azote was discovered by M. Courtois, and subsequently
examined by M. Colin. Iodine, brought in contact with ammoniacal gas,
a combination taking place, produces a viscid shining liquid of a
brownish-black colour, which, as the saturation goes on, loses its
lustre.

This liquid does not detonate, and is considered to be an iodide of
ammonia; but, when it is added to water, it is decomposed, as well as
the water, and we obtain two new compounds, as before observed, the
hydriodate of ammonia, and iodide of azote. This iodide detonates.
Hence it is evident, that hydrogen united with azote, in ammonia,
prevents explosion; for the moment it is taken away, by the formation
of hydriodic acid, and the azote itself combines with the iodine,
a fulminating compound is formed. The elements of this powder are
feebly united.

It is found, that hydriodate of ammonia has the property of
dissolving a large quantity of iodine, and, if suffered to remain
with the iodide of azote, of decomposing it also, and setting the
azote at liberty. Water is said to have the same effect, although
feebly.

Iodate of potassa, a salt composed of iodic acid and potassa, when
mixed with sulphur, and struck with a hammer, will detonate, in
consequence of the decomposition of the iodic acid. The iodate
of potassa may be formed very readily by agitating iodine with
a solution of caustic potassa. The water is decomposed, and the
hydriodate of potassa is also formed, which, being very soluble,
remains in solution, whilst the iodate separates, on concentrating
the liquor, and suffering it to stand.

Chlorate, as well as nitrate of silver, form with sulphur fulminating
powders.

Iodic acid, called also oxy-iodine, (prepared by exposing iodine to
the action of euchlorine,) when heated in contact with inflammable
substances, and the more combustible metals, will produce detonations.

It appears, however, that sulphur has a stronger affinity for oxygen
than iodine has, and iodine a stronger affinity than chlorine for
the same element. Hence chloric acid is more readily decomposed
by inflammable bodies than iodic acid, and iodic acid, sooner than
sulphuric acid.

The acids, which chlorine, iodine, and sulphur form respectively
with oxygen, Gay-Lussac remarks, have their elements more strongly
_condensed_, than the same substances united with hydrogen.

_Sect. XXXI. Of Detonating Oil, or Chloride of Azote._

This oil is produced by the action of chlorine on ammonia, by using
some of the salts of this alkali. A small jar of chlorine gas is
transferred into a basin, containing a solution of nitrate or muriate
of ammonia, a little heated: an absorption will gradually take
place, and the gas be condensed. An _oily film_ will now appear on
the surface of the ammoniacal solution, which, as it increases, will
form globules and fall through the liquor. This substance is the
detonating oil, composed, according to analysis, of chlorine, azote,
and hydrogen. It is supposed by Messrs. Wilson, Porret, and Kirk,
that the hydrogen serves as a medium of union between the chlorine
and azote, and that, in detonation, the powerful effect is owing to
the chlorine.

Detonating oil explodes violently at 212 degrees; and even when
touched with cold inflammable substances, as a portion of olive oil,
about the size of a pin's head, the detonation is also violent, and
the vessel, in which the experiment is made, will, in most cases, be
broken into fragments.

Detonating oil is considered, however, a chloride of azote. In order
to prevent the decomposition of the chloride by the ammoniacal salt,
a thin stratum of muriate of soda, put into the bottom of the vessel,
is recommended. Its specific gravity is 1.653. Warm water, put into
a vessel containing it, will change it to an aeriform fluid of an
orange colour. "I attempted," says Sir H. Davy, "to collect the
products of the new substances, by applying the heat of a spirit-lamp
to a globule of it, confined in a curved glass tube over water: a
little gas was at first extricated; but, long before the water had
attained the temperature of ebullition, a violent flash of light was
perceived, with a sharp report; the tube and glass were broken into
small fragments, and I received a severe wound in the transparent
cornea of the eye, which has produced a considerable inflammation of
the eye, and obliges me to make this communication by an amanuensis.
This experiment proves what _extreme_ caution is necessary in
operating on this substance; for the quantity I used was scarcely as
large as a grain of mustard seed." _Phil. Trans._ 1813, Part I.

In _vacuo_, it expands into vapour, which still possesses the power
of exploding by heat. In water, it gradually disappears, the water
becoming acid, and azote being evolved. Mercury decomposes it, and a
white powder (calomel) is formed, while the azote is set at liberty.

Dr. Ure (_Chemical Dictionary_, Art. _Nitrogen_,) observes, that the
mechanical force of this compound, seems superior to that of any
other known substance, not even excepting the ammoniacal fulminating
silver. The velocity of its action appears to be likewise greater.

The Doctor touched a minute globule of it, in a platina spoon,
resting on a table, with a fragment of phosphorus at the point of a
pen-knife, and the blade was instantly shivered into fragments by the
explosion.

Messrs. Porret, Wilson, and Kirk (_Nicholson's Journal_, Vol. XXXIV,)
employed 125 different substances, by bringing them in contact; and
out of that number the following caused it to explode:

Supersulphuretted hydrogen,
Phosphorus,
Phosphuret of lime,
Phosphuretted camphor,
Camphoretted oil,
Phosphuretted hydrogen gas,
Caoutchouc,
Myrrh,
Palm oil,
Ambergris,
Whale oil,
Linseed oil,
Aqueous ammonia,
Olive oil,
Sulphuretted oil,
Oil of Turpentine,
---- Tar,
---- Amber,
---- Petroleum,
---- Orange peel,
Naphtha,
Soap of silver,
---- Mercury,
---- Copper,
---- Lead,
---- Manganese,
Fused Potassa,
Nitrous gas.

See _Detonating Works_.

According to Mr. Davy, chloride of azote contains
4 vols. of chlorine = 10 + } or { 4 primes = 18.0 +
1 ---- azote = 0.9722 } { 1 ---- = 1.75,
or very nearly 10 by weight of chlorine to 1 of azote.

_Sect. XXXII. Of Pyrophorus._

Pyrophorus is a black substance, which takes fire spontaneously, when
brought into contact with air. It is the luft-zunder, or air-tinder
of the Germans. It first emits sulphuretted hydrogen gas, and in a
few seconds becomes red-hot, burning with a bluish flame. Pyrophorus
consists of alumina, charcoal, and sulphuret of potassa, and also,
according to some, of potassium, which is alleged to be formed in its
preparation. Be this as it may, it seems, that water is decomposed in
its combustion, that sulphuretted hydrogen gas is emitted, which is
inflamed by the oxygen gas of the atmosphere, and that, during the
combination of oxygen, a degree of heat is produced, which causes
the ignition of the charcoal, as well as the inflammation of the
remaining sulphur.

Pyrophorus may be formed in several ways, all of which produce the
same result. The usual process is the following: Take equal parts of
brown sugar and alum, and melt them in a ladle. Continue the heat,
stirring them constantly until a spongy black mass is formed. Let
this mass be reduced at once to powder, and introduced into a common
green glass phial, of the capacity of about six ounces, previously
coated outside with a mixture of pipe-clay and solution of borax.
Immerse the phial in a crucible, filled with sand, closing the mouth
of the former with a piece of charcoal, or a glass tube inserted in
it. Upon the crucible being exposed to a red heat, an inflammable
gas will escape, which will take fire.[21] When this effect ensues,
the heat must be continued for about twenty minutes longer, at the
expiration of which time, the crucible must be removed from the fire,
and the phial taken out and closely stopt. The pyrophorus is to be
preserved in a ground stoppered bottle. The addition of one-sixteenth
part of sulphate of soda, or Glauber's salt, to the alum and sugar,
is said to make the pyrophorus with more certainty. Various vegetable
substances, besides sugar, as flour, starch, &c. may be used.
Three parts of alum, and one part of wheat flour will make a good
pyrophorus.

Homberg discovered this substance, in the year 1680. Hence it is
sometimes called Homberg's pyrophorus. He was operating upon a
mixture of human excrement and alum; and, when he examined the
contents of his vessel, in three or four days after, he was surprised
to see it take fire spontaneously, when brought to the air. Soon
after Lemery, the younger, discovered, that honey, sugar, flour,
or almost any animal or vegetable matter, could be used in lieu of
human fæces; and, as Macquer informs us, M. Lejoy de Suvigny showed,
that other salts, containing sulphuric acid, may be substituted for
alum. Mr. Scheele (_Treatise on fire_, &c.) found by experiment,
that, when alum was deprived of potassa, it was incapable of forming
pyrophorus, and that vitriolated tartar (sulphate of potassa) may be
used in the place of alum. The experiments of Mr. Proust prove, that
a number of neutral salts, composed of vegetable acids and earths,
when submitted to heat, leave a residuum that inflames spontaneously.
This statement agrees with the experiments of M. Chenevix. From the
experiments and observations of sir H. Davy, and Dr. J. R. Coxe,
late professor of chemistry, but now of materia medica, &c. in the
University of Pennsylvania, it is rendered very probable, that
pyrophorus owes its property of inflaming spontaneously to a small
portion of potassium, which is formed in the process.

The preparation of pyrophorus is explained on the principle, that the
vegetable matter is first decomposed; that the hydrogen and a part
of the carbon decompose the sulphuric acid of the alum, by uniting
with its oxygen; that water, carbonic oxide, and carburetted hydrogen
are disengaged, along with a part of the sulphur; and that, while
the excess of charcoal remains intimately mixed or divided with the
alumina, the sulphur and the sulphuret of potassa, form together a
compound, which has the property of inflaming spontaneously in the
open air. Some suppose, as alum is a triple salt, having potassa, as
well as alumina, for its base, that the potassa is decomposed in the
process, and potassium, as we remarked, produced; to the presence of
which they ascribe the singular property of inflaming in the open air.

The spontaneous combustion of charcoal, in several instances, is
supposed by some to have been owing to the presence of pyrophorus, by
others to phosphorus, and by others again to nascent hydrogen. To the
presence of this substance, is attributed the explosion of gunpowder
mills. (See _Gunpowder_.)

Several different mixtures, and torrefied substances, form a kind of
imperfect pyrophori, and have more than once occasioned fires, from
no suspicion of their properties being entertained.

Besides pyrophorus, other compositions, which, in like manner, take
fire on exposure to the open air, have been by degrees made known to
us: 1. The scoria of the martial regulus of antimony, or antimony
freed from sulphur by the intervention of iron and nitre, as well
crude as also after being dissolved, have been observed to take fire
spontaneously, when laid upon a hot stone, or in the sun. Of the
truth of the latter case, Wiegleb says, he is assured by his own
experience. 2. The residuum of the acetate of copper is another
pyrophorus. 3. Some assert, that they have observed an inflammation
ensue from honey and flour, calcined according to the rules laid
down. 4. According to Geoffroy, a calcined mass of three parts of
black soap, and one of diaphoretic antimony, has been known to take
fire spontaneously. 5. Meuder has observed, that a pyrophorus is
obtained, when equal parts of orpiment and iron-filings are sublimed
together, and ten parts of this sublimate are triturated in a mortar
along with twelve of nitrate of silver. 6. A pyrophorus is produced,
according to Penzky, when two drachms of white sand, three of common
salt, one of sulphur, two of sulphuric acid, and half an ounce of
muriatic, are mixed together and distilled in a glass retort. In
this operation, a sublimate is said to be obtained, which bursts
out in flames, as soon as it comes into contact with the air. 7.
The spontaneous precipitate of osteocolla, from a solution of it in
sulphuric acid, after having been separated by means of a filter,
and dried, took fire in a warm place. S. Pott observed the same
phenomenon in the earth of the residuum, after the distillation of
urine, that had been putrid for a considerable time. 9. To these
may also be referred, a mass composed of equal parts of sulphur and
iron-filings; which, when thoroughly moistened with water, after some
time, grows hot, swells, and at last breaks out into vapour, smoke,
and flame. (See _Artificial Volcano_.)

Cadet's fuming liquor, prepared by distilling equal parts of acetate
of potassa, and arsenious acid, emits a very dense, heavy, fetid,
noxious vapour, which inflames spontaneously in the open air. Black
wadd, an ore of manganese, when dried by the fire, and mixed with
linseed oil, gradually becomes hot, swells, and then bursts into
flame.

M. Chenevix (_Annales de Chimie_, tom. LXIX,) remarks that almost
all the metallic residuums, which are formed by the distillation
of acetates _per se_, are pyrophoric, after cooling; which Mr. C.
attributes to the presence of finely divided charcoal, mixed with the
metallic part. He experimented on several acetates, with the view
of ascertaining the quantity of pyroacetic spirit they would yield,
and found, in every instance, that charcoal existed in the residue,
sometimes with reduced metal, and at other times with metallic
oxide. A table of these experiments may be seen in Ure's _Chemical
Dictionary_. The residuum of acetate of copper has long been known to
possess pyrophoric properties.

_Sect. XXXIII. Of Sal Ammoniac._

This salt enters into the composition of fire-works, to give, more
particularly, a peculiar colour to flame, which is that of green, or
yellowish-green. Sal ammoniac is a salt, composed of muriatic acid
and ammonia, and, when pure, is white, and capable of being sublimed
without decomposition. Its purity may be known by its complete
volatilization. It is readily pulverized.

The experiment, showing the formation of sal ammoniac by a direct
union of its component parts, may be made by bringing in contact, in
a glass receiver, muriatic acid gas and ammoniacal gas. White clouds
will form, a condensation take place, and muriate of ammonia be
deposited on the sides of the vessel.

Sal ammoniac was altogether made, at one period, from the soot of
camels' dung, or of other animals, which feed on saline plants. The
excrement was burnt, the soot collected, and sublimed. This was the
process practised in Egypt. The composition of sal ammoniac being
known, the process for obtaining it was improved; so that, instead
of using the soot of dung, it is now formed by the distillation of
bones. The impure ammoniacal liquor, thus obtained, is combined with
sulphuric acid, by an easy process, and the resulting sulphate of
ammonia is then decomposed by muriate of soda, by which sulphate of
soda and muriate of ammonia are produced. They are separated, and the
latter is formed into heads by sublimation. In this state, it occurs
in commerce. It was made in great quantity in the vicinity of the
temple of Jupiter Ammon; and hence its name.

Mr. Minish, according to the English writers, is entitled to this
method of converting impure liquid ammonia into sal ammoniac. The
following is an outline of his process. He suffered the impure
ammoniacal liquor to percolate through a stratum of bruised gypsum,
and as carbonate of ammonia is contained in the liquor, the fluid,
which filters, would contain sulphate of ammonia, the carbonate
of lime being insoluble. This sulphate he evaporated, and the dry
mass, mixed with muriate of soda, was sublimed. If I am not greatly
mistaken, however, although I have not the work to refer to, this
process is described in Dr. John Pennington's _Chemical Essays_, a
work published in Philadelphia, about 1792. Dr. Pennington's work,
we may observe, is the first chemical book which was published
in the United States, and contains numerous important facts and
observations. That this process was known in Philadelphia, and used
at the _Globe works_, or rather _Glaub works_, (from the circumstance
that Glauber's salt was made there,) is within the recollection of
many. I heard the late professor Wistar speak of this process, and of
the economy in using gypsum.

Mr. Lebanc (_Annales de Chimie_, vol. XIX.) invented a process, by
which he brought the ammoniacal gas and muriatic acid gas in contact,
in a chamber lined with lead. In one pot, he put common salt and oil
of vitriol; in another pot, animal matter. Being conducted by pipes
into the chamber, the gases united, and sal ammoniac was formed.
Other improvements have been made, as obtaining ammonia from coal
soot, &c.

Ammonia is generated in artificial nitre beds, and is at first united
with nitric acid; which compound is subsequently decomposed, as the
process of putrefaction goes on, by the potassa, calcareous earth,
&c. present in nitre beds. _See Nitrate of Potassa._

Sal ammoniac is ready formed in the soot of animal feces, twenty-six
pounds of which yield six of the salt. According to Siccard, who
published, in 1716, an account of the fabrication of sal ammoniac in
Egypt, which Geoffroy, in the same year, proved to be a compound of
the spirit of sea salt and volatile alkali, sea salt and urine were
used in that country. The account, however, given by Lemery, in 1719,
makes no mention of either sea salt or urine.

Sal ammoniac is found native. It occurs in the vicinity of burning
beds of coal, both in Scotland and England, and is met with in
volcanic countries. When triturated with quicklime, it exhales
ammonia, which is a characteristic of all ammoniacal salts.

Sal ammoniac is often found in crusts of lava. Sir William Hamilton
observes, that, in the fissures formed by the lava, this salt
sublimes. He found, in the same locality, common salt.

Sal ammoniac is decomposed by a variety of substances. Sulphuric
acid will disengage the muriatic acid from it, while lime, potassa,
&c. liberates the ammoniacal gas, which, when combined with water by
distillation or other means, forms the common spirit of sal ammoniac,
or water of ammonia. Mixed with carbonate of lime and sublimed, it
produces the carbonate of ammonia, usually called mild volatile
alkali, or pungent smelling salts. Ammonia, in a separate state,
unites with some metallic oxides, giving rise to certain fulminating
powders, which have been already noticed. That iodine decomposes
ammonia, we have shown, when on the preparation of iodide of azote,
or fulminating powder.

Sal ammoniac enters into the composition of candles, to prolong their
duration. The process recommended in the _Archives des Découvertes_
is the following: Dissolve, in half a pint of water, a quarter of
an ounce of sal ammoniac, two ounces of common salt, and half an
ounce of saltpetre, and add the solution to three pounds of mutton
tallow, and eight pounds of beef tallow, previously melted. Continue
the heat until all the water is evaporated. It is then suffered to
cool, and, when used, is to be melted with a quarter of an ounce of
nitre, and formed into candles in the usual manner. This preparation
of tallow is highly recommended on account of its economy, as well as
the improvement itself. A candle, made of this tallow, will burn two
hours longer than one of the ordinary kind.

Another process for making candles, in which sal ammoniac is used,
is mentioned in the _Annales des Arts et Manufactures, Nos. 142 and
146_. Eight pounds of suet are melted, and a pint of water is added.
The tallow is again submitted to heat, and the same quantity of
water, holding in solution half an ounce of saltpetre, half an ounce
of sal ammoniac, and one ounce of alum, is added. It is then suffered
to stand, and when used is re-melted. The wick is first dipped in a
mixture of camphor and wax. Care must be taken, before the tallow is
used, to evaporate the water. Equal parts of beef and mutton tallow
are recommended.

_Sect. XXXIV. Of Corrosive Sublimate._

Corrosive sublimate, known in chemistry by the names of corrosive
muriate, and perchloride of mercury, is made use of in some
preparations of fire-works, and particularly in the composition
of stars, in which it is mixed with a variety of substances, such
as steel filings and antimony, in order to vary the appearance of
the flame, and to communicate to it particular colours. Corrosive
sublimate is formed by various processes, among which we may
enumerate the following: Take five parts of sulphuric acid, four
parts of mercury, four parts of muriate of soda, and one part of
black oxide of manganese. Boil the mercury in the sulphuric acid,
until it forms a dry sulphate, which is to be reduced to five parts.
Mix the sulphate thus formed, with the muriate of soda, previously
dried, and the oxide of manganese, and sublime the mixture. By this
process the sulphuric acid of the sulphate unites with the soda, and
forms sulphate of soda; while the muriatic acid of the muriate of
soda combines with the oxide of mercury, (which receives an addition
of oxygen from the oxide of manganese,) and forms the perchloride,
called by Thenard the deutochloride of mercury. The same process is
used without the addition of manganese. By exposure to heat, the
sublimate sublimes, and the sulphate of soda forms the residuum.
The same salt, if re-sublimed with an addition of crude mercury,
will be changed into the protochloride of mercury, or calomel. Or,
if the sulphate of mercury and muriate of soda be mixed with crude
mercury, and sublimed, calomel will be formed at one operation. It is
sufficient to observe, that corrosive sublimate is one of the most
virulent of poisons when swallowed; and therefore should be used with
caution.

It is soluble in water, and capable of crystallizing. It is also
soluble in alcohol, to the flame of which it communicates a
yellow colour, and in sulphuric, nitric, and muriatic acids. It
is decomposed by alkalies, forming with ammonia a triple salt,
(_Sal Alembroth_,) by the alkaline earths, and the metals or their
sulphurets; and, when distilled with arsenic, bismuth, antimony, or
tin, the mercury is separated.

The proper antidote for corrosive sublimate, is the white of egg or
albumen, which converts it into calomel. Sulphuretted hydrogen water
may also be employed along with emetics. The effect of albumen, in
this way, may be relied on.

_Sect. XXXV. Of Orpiment._

Orpiment, or the yellow sulphuret of arsenic, which is either native
or artificial, is principally used in fire-works for the composition
of stars. Orpiment is divided by some into two kinds; viz. the red,
called realgar, and the yellow, called yellow arsenic.

Arsenic combines readily with sulphur. When they are mixed together,
and put into a crucible and fused, the product will be a red vitreous
mass. This red sulphuret may also be formed, by melting sulphur with
arsenious, or arsenic acid. Sulphurous acid gas will be evolved,
evidently showing that a portion of the sulphur unites with the
oxygen of acid employed.

When arsenious acid, known in commerce by the name of white arsenic,
and called by some oxide of arsenic, is dissolved in muriatic acid,
and a solution of sulphuretted hydrogen in water is added, a yellow
precipitate will be obtained which is orpiment. The hydrogen, in
this case, unites with the oxygen of the arsenious acid, by which the
metal is reduced, and the sulphur then combines with it. A mixture of
sulphur and arsenic, exposed to a heat not sufficient to melt them,
will sublime into a yellow sulphuret.

Both the yellow and red sulphurets are employed in fire-works. They
are not, however, required, except in particular cases. In the
composition of Bengal lights, given in the Bombardier or Pocket
Gunner, by R. W. Adye, orpiment is used. According to the same
author, it is also used in Chinese white lights. Both the yellow and
red sulphuret of arsenic will detonate with chlorate of potassa.

_Sect. XXXVI. Of Antimony._

The antimony, which enters into the composition of many fire-works,
is not to be understood to be the metallic, or regulus of, antimony,
unless so expressed; but the crude antimony of the shops. Crude
antimony is a combination of antimony and sulphur, and is usually
met with in fine powder. That both antimony and its sulphuret have
a powerful effect in modifying the flame of gunpowder, and all
compositions, in which nitre and inflammable substances form a part,
is evident from the many cases, in which it is employed, and from the
effects that thereby result.

The different substances in any inflammable compound, intended
to produce particular colours, should be so mixed, as that, from
a knowledge of the proportions which produce such colours, the
_effect_ may be retained, even when it is mixed with other bodies.
For this reason, the artist should know the different effect of each
ingredient. Some may show themselves in the flame, some in sparks,
some in stars, others in fire-rain, and the like, as the case may
be. Antimony, for instance, produces a reddish flame, if it be
in a proper proportion, and not altered by the presence of other
substances. Hence, when antimony is mixed with nitre, the flame will
be more or less a _whitish-green_.

This modification, or change in the appearance of flame, is apparent
in certain compounds, of which antimony constitutes a part. Thus,
antimony is used in the preparation of the common rocket stars, in
drove stars, in the fixed pointed stars, in some of the gold and
silver rains, in the slow and dead fire for wheels, in tourbillons
for crowns or globes, in the composition of serpents, lances for
illumination, Bengal lights, and many other kinds of fire-works.
According to Adye, (Pocket Gunner,) it enters into the composition of
carcasses, Chinese lights, &c.

When it is as one to sixteen of nitre, the gunpowder being as four,
and the sulphur, eight, the composition will produce a white flame;
but when it is in the proportion of eight to sixteen of nitre,
without any addition, the flame will be blue. By substituting, in its
place, eight of amber to sixteen of nitre, with sixteen of sulphur,
and eight of meal powder, this change will produce a yellow flame. It
is obvious, however, that these and similar changes are owing to the
proportions, as well as to the substances used.

Antimony, in the state of a sulphuret, when mixed with chlorate of
potassa, &c. will form detonating compounds.

Antimony is a grayish-white metal, more or less brilliant and
laminated. It is brittle, and may be easily reduced to powder. It
melts at a red heat, and evaporates at a higher temperature: on
cooling, it crystallizes. It undergoes no change by exposure to the
air, except the loss of its lustre. When steam is made to pass over
ignited antimony, the decomposition of the water is so rapid, as to
produce a violent detonation. At a white heat, it burns, and forms a
white coloured oxide, called the _argentine flowers of antimony_. Its
oxides are various, some of which, possessing acid properties, are
called acids. The protoxide is gray, the antimonious acid, white, and
antimonic acid, of a straw colour. The crocus of antimony, and the
glass of antimony are oxides of this metal, but in particular states
of combination. It unites with several of the acids. Its oxide, with
tartaric acid, and tartrate of potassa, forms _tartar emetic_. With
chlorine, it constitutes the butter of antimony.

The artificial sulphuret may be formed, by melting sulphur and
antimony together. The native sulphuret is almost the only ore of
antimony, and is the mineral from which the regulus is obtained. It
unites with the metals, forming alloys of different kinds.

_Sect. XXXVII. Of Carbonate of Potassa._

Potassa, either pure or carbonated, retards the progress of
combustion; and, therefore, may prevent, according to the proportion
employed, the action of combustible bodies on nitre. Combustion may
be retarded by using those substances, which are not in themselves
inflammable, and which, if used in too large a quantity, would
effectually prevent it. Clay, wood ashes, &c. as in the blind
fuse, act on this principle; and serve, also, in particular cases,
to produce that succession of explosions, which renders the effect
of some fire-works, more grand and impressive. Rope, soaked in a
solution of saltpetre and dried, would burn rapidly, were it not for
the after immersion in potash ley, or urine, either of which acts by
retarding the progress of combustion. The same thing may be said of
other bodies, the use of which will claim our attention hereafter.
Potassa, although not generally used for the purposes mentioned, as
it is apt to deliquesce, or absorb water, and thus destroy the effect
altogether, may be more advantageously employed in a liquid state, as
in the preparation of slow match in the way stated under that head.
But as match rope is now generally superseded by the port-fire, as a
more certain method of firing cannon, it would be unnecessary, as it
is irrelevant, to enlarge on this head. The use, also, of the priming
fuse, which conveys the fire to the powder in the gun, with certainty
and with rapidity, is an improvement of no small moment.

Alum has also been used for the purpose of checking the rapidity of
combustion, in some particular fire-works. In one of the formulæ
for the preparation of _fire-balls_, to be thrown with the hand,
or fired from a gun, given in the _Memoir on Military Fire-works_,
as taught at Strasburg, in 1764, there is, besides sulphur, mutton
suet, saltpetre, and antimony, _nitre of alum_, equal to one-fourth
of the weight of the compound. That this salt, the supersulphate of
alumina and potassa, is used to make paper, as cartridge paper, &c.
incombustible, is a fact, with which every one is acquainted.

We might, also, enumerate the uses of glue, isinglass, gum arabic,
&c. for similar purposes; and also of wood-ashes, in the composition
of the, so called, blind fuse. Light twisted white rope, when soaked
in strong ley, or a strong solution of potash, we are informed, will
form a slow match that will burn only three feet in six hours.

Potash is obtained from wood-ashes, by lixiviation with water, and
evaporation. It contains more or less impurities; and always carbonic
acid, from which it is separated by quicklime, the alkali being
rendered caustic. Some of the foreign ingredients are burnt off by
exposing it to heat in an oven. It then assumes a white, somewhat
_pearly_ appearance, and takes the name of pearl-ash, but is still
the same alkali.

Wood-ashes, when mixed with quicklime, and lixiviated, produce
caustic ley, the strength of which depends on the quantity of alkali
held in solution. It is this ley, when boiled with oils, fat, &c.
that produces soft soap. Hard soap is a combination of oil or fat,
and soda. The quantity of real alkali in potash may be known by the
proportion of acid required to saturate a given weight of it. Potash,
pearl-ash, salt of tartar, and salt of wormwood are all carbonates
of potassa. This alkali is called the vegetable alkali, because it
is obtained from vegetables. It is considered to be the hydrated
deutoxide of potassium, and when decomposed will furnish potassium.

_Table of the saline or soluble products of one thousand pounds of
ashes of the following vegetables._

SALINE PRODUCTS.

Stalks of Turkey wheat, 198 lbs.
Stalks of sun-flower, 349
Vine branches 162.6
Elm 166
Box 78
Sallow 102
Oak 111
Aspen 61
Beach 219
Fern, cut in August, 116, or 125 according to Wildenheim.
Wormwood 748
Fumitory 360
Heath 115

The observations of Mr. Kirwan on potash may be seen in _Aikin's
Chemical Dictionary_.

When a piece of hydrated potassa is placed between two disks of
platinum, which are brought in contact with the poles of a galvanic
battery, consisting of upwards of 200 pairs of plates, four inches
square, the oxygen will separate at the positive surface, and small
metallic globules of potassium will be formed at the negative
surface. The potassa, in the mean time, will undergo fusion.

Sir H. Davy discovered potassium, in 1807. It may be obtained by
means of iron turnings, in the following manner: Heat the iron
turnings to whiteness in a curved gun barrel, and suffer potassa,
in a state of fusion, to fall upon them very gradually, air being
excluded: potassium will form, and collect in the cool part of the
tube. For the different facts respecting this metal, consult Sir H.
Davy's communications on the subject, and the memoirs of Gay-Lussac
and Thenard, Curadeau, &c. See also, Davy's _Chemical Philosophy_,
and Thenard's _Traité de Chimie_.

Potassa unites with, and neutralizes, acids, and forms salts; the
principal of which are the sulphate, muriate, and nitrate of potassa.
It unites also with sulphur, phosphorus, &c.

Potassa, in the state of carbonate, is very soluble in water, for
which it has so strong an affinity, that, when exposed to the
atmosphere, it deliquesces and becomes fluid. Caustic potassa
undergoes the same change, in a more remarkable degree. It is on
account of its great avidity for water, that the carbonate is used in
the preparation of alcohol from spirituous liquors; it retaining the
water, while the alcohol may be distilled over.

Potassa has a stronger affinity for the acids, than either the earths
or metals; hence it decomposes earthy and metallic salts, the earth
or metallic oxide being precipitated, while it unites with the acid
of the salt. It is on the same principle, that earthy and metallic
salts decompose soap; and waters which are hard, and owe that
property to the presence of earthy salts, will curdle, or, in other
words, decompose soap. Such waters, for this reason, are called hard.
Acids have the same effect in decomposing soap.

The use of potassa is very apparent in the manufacture of saltpetre.
When the nitric acid is combined with an earthy base, as in the
calcareous nitre of the nitre caves of the western country, potassa
from wood-ashes will decompose it, on the principle already stated;
and, by combining with the nitric acid, form nitrate of potassa.
It is used also in refining saltpetre, where earthy salts are
present, besides common salt. The effect of this alkali, for that
purpose, will be more obvious, by referring to the processes for the
extraction and refining of saltpetre, in the article on that subject.

Potassa acts as a flux for siliceous substances and forms glass.
These are its prominent characters.

_Sect. XXXVIII. Of Wood-Ashes._

Wood-ashes, the product of the combustion of wood, contain potassa,
some foreign salts, and earthy and sometimes metallic substances,
insoluble in water. The quantity of alkali, which ashes, obtained
from different woods, furnish, is greater or less, according to
the nature of the wood. The ashes of the oak are generally used in
pyrotechny; but it seems to us, that ashes in common will have the
same effect.

The ashes, for this purpose, should be dry, and passed through a fine
sieve. They enter into the composition of blind fuse.

In some instances, the _leached_, or lixiviated ashes might be used.
The residue, after the separation of alkali and saline matter by
the action of water, is nothing more than the insoluble part of the
ashes. Caustic ley is always obtained from wood-ashes, by mixing them
with about a fiftieth part of quicklime, and putting them into a
barrel or tub, and adding water. The lime takes up the carbonic acid,
and the ley comes off in a caustic state. If the solution should not
contain a sufficient quantity of potassa, or not bear an egg, as
that is the usual criterion of its strength, (which depends on its
specific gravity,) its strength may be increased by evaporation; and,
if too strong, simple dilution with water, is all that is necessary.

While the ashes of some plants, as the upland plants, generally yield
potassa; others, as many marine plants, the _salicornia europea_,
_salsola tragus_, _salsola kali_, _&c._ afford soda by incineration.
It will be sufficient, however, to observe, that the ashes of all
plants contain alkali, in more or less quantity, which depends on
various circumstances; and that the alkali may be extracted by
lixiviation, and, in some instances, may even be seen among the
ashes, in a semivitrified mass. The white ashes, which are formed
by the combustion of animal matter, as osseous or bony substances,
we may remark, do not afford potassa or soda, but only phosphate of
lime, and some uncombined earths. Bones, nevertheless, may, like
wood, be carbonized, although the charcoal formed is of a different
nature. For the preparation of phosphorus from bone-ash, see the
article Phosphorus.

_Sec. XXXIX. Of Clay._

Clay is an argillo-siliceous substance, of a colour more or less
yellow, and containing a variable quantity of silica and alumina,
with oxide of iron. There are a variety of clays; the common potter's
clay, pipe clay, porcelain clay, &c. Some contain, and others are
free from iron. Those that contain this metal burn _red_; while those
which remain, or become white in the process of burning, are free
from it.

The use of clay in fire-works is confined nearly altogether to
rockets. In the driving of sky-rockets, &c. the _charge_ must
always be driven one diameter above the piercer, and on it there is
sometimes rammed one-third of a diameter of clay, through the middle
of which a hole is bored to the composition, so that, when the charge
is burnt to the top, it may communicate its fire through the hole,
to the stars in the head. This, however, is not always the case. See
_Rockets_.

The clay for fire-works, is usually prepared of the common kind,
which contains neither stones nor sand. It must be first baked in an
oven, until perfectly dry, and then pulverized, and sifted through
a common hair sieve. In China, the Chinese mostly employ, for this
purpose, their white porcelain clay.

_Sec. XL. Of Quicklime._

Lime, as it is found in nature, is combined with carbonic and
sulphuric acids, and less frequently with some of the other acids,
as the nitric, fluoric and phosphoric. Calcareous carbonates are the
most abundant; in which we include marble, limestone, and chalk; and
the sulphate, or gypsum, may be considered the next. Lime constitutes
the basis of marine shells; for, when burnt, they furnish quicklime.
Its union with nitric acid is well known, forming the calcareous
nitre of the saltpetre caves of Kentucky, &c. We have mentioned this
combination under the head of nitre.

Without enumerating all the chemical properties of lime, it will be
sufficient to remark, that it is composed of calcium and oxygen,
and, when slaked with water, will evolve caloric in a free state,
while the water solidifies or combines with the lime; that it
forms with water, a solid hydrate, an example of which combination
is afforded by the preparation of mortar; that it dissolves in
water, and forms lime-water, and is slaked by exposure to the air,
absorbing, at the same time, carbonic acid; that it unites with
acids, like other salifiable bases, and forms salts, some of which
are soluble in water, and others not; that it deprives the alkalies
of carbonic acid, and renders them caustic, being itself changed into
a carbonate; and, that it unites with sulphur and phosphorus, forming
a sulphuret and phosphuret, and, also, with hydroguretted sulphur,
and sulphuretted hydrogen, forming a hydroguretted sulphuret, and a
hydro-sulphuret.

When limestone, marble, &c. are burnt in a kiln, the carbonic acid
is expelled, and quicklime formed. Quicklime and lime, chemically
speaking, are synonimous terms.

The fluor, or Derbyshire spar, is a fluate of lime. When this
substance is distilled in a leaden retort, with sulphuric acid,
we have sulphate of lime, and fluoric acid gas, called by some
hydro-fluoric acid. This acid, when received in water, is used to
etch on glass, in the same manner as nitric acid on copper; and while
applied in a liquid state, or in that of gas, it acts on the glass,
by combining with the silicon, and is changed from the hydrofluoric,
into the silicated fluoric acid. If, instead of employing a leaden
vessel, we make use of a glass retort, or introduce powdered glass
or silica, into the leaden vessel, in either case, we obtain another
acid, which we have just mentioned, the silicated fluoric acid; in
consequence of the union of silicon with the supposed radical of the
fluoric acid, known by the name of fluorine.

Quicklime is occasionally, though but rarely, employed in fire-works.
That it increases the strength of powder, is asserted by Dr. Bayne.
See Gunpowder. Its use in making slow match, along with other
substances, is given in the article on that subject.

_Sec. XLI. Of Lapis Calaminaris._

That some of the ores of zinc are employed in fire-works, is evident
from the use of lapis calaminaris, or calamine stone, which is an
impure carbonate of zinc. Calamine should be finely pulverized and
sifted. As zinc gives a particular colour to flame, (see _zinc_),
its carbonate may also communicate a colour, and, under particular
circumstances, may produce a great variety, and, therefore, in
such cases, be preferable to the zinc itself. It is one of the
ingredients in the _dead fire_ for wheels, which is composed of lapis
calaminaris, saltpetre, brimstone, and antimony.

The modifications, to which particular bodies are subject, as to
their respective effects, depend very greatly on the presence of
other bodies, and frequently on the chemical action, which ensues
throughout; so that, as we had occasion to observe, the _effect_
which one body would produce on the flame, maybe completely changed,
modified, or varied by the presence of a second, third, or fourth
substance. The art, therefore, of uniting various bodies, in kind,
as well as in proportion, so as to produce a given effect, can be
acquired only by a series of experiments. Zinc, as a metal, when
finely divided, produces a peculiar effect; when mixed with other
metals, and with certain salts, as sal ammoniac, another; and, when
combined with some acids, as the carbonic in lapis calaminaris, a
third effect; and these effects may be governed, as it appears, by
the presence or absence of certain bodies. This fact will appear
more striking, when we consider the various mixtures, and their
respective properties. For the uses of zinc, see that article.

_Sec. XLII. Of Zinc._

Zinc, commonly called spelter, is a metal, obtained from blende,
or sulphuret of zinc, and calamine, or carbonate of zinc. The ore
is first roasted, and then mixed with some carbonaceous flux, and
submitted to the action of heat in close vessels. The metal is
volatilized, and passes over, and is usually caught in water. It is
then fused, and cast in moulds.

Zinc possesses many remarkable properties, some of which are the
following. It is of a brilliant white colour, with a shade of blue,
and is composed of a number of thin plates, adhering together. Its
specific gravity is more than six times that of water. It is brittle,
but, when heated to 212 degrees, may be hammered out, or made into
sheets. At 400° it becomes very brittle. Its tenacity is so feeble,
that a wire of 1/10th of an inch in diameter, will support a weight
of only 26 pounds. At 680° it melts, and above that temperature,
evaporates. It soon oxidizes, and its lustre is therefore tarnished.
At common temperatures, it soon decomposes water; and, when the
vapour of water is passed over it at a high temperature, the
decomposition is very rapid, the oxygen of the water being absorbed.
Zinc is soon oxidized when melted and exposed to the air, forming a
gray oxide.

At a red heat, zinc inflames, and the product of combustion is the
white oxide of zinc, or flowers. The oxide of zinc is reduced by
mixing it with charcoal, and exposing the mixture to a strong heat in
close vessels.

Zinc will burn in chlorine gas, and forms a chloride of zinc. If the
perchloride of mercury and zinc-filings be heated together, the same
compound will result. This chloride melts at 212°, and rises, in the
gaseous form, at a heat much below ignition. It was formerly called
the _butter of zinc_, and muriate of zinc. With iodine, zinc forms a
compound, called iodide of zinc.

With phosphorus and sulphur, zinc also combines, and with the latter,
it forms the native sulphuret, known by the name of blende. It
unites, also, with acids, and forms salts. Of these, the sulphate of
zinc, or white vitriol, is the most common. It unites with various
metals, forming alloys. Of these, that with copper, called brass, is
the most known. Zinc, with copper, forms galvanic batteries. With
tin and mercury, it constitutes amalgam for electrical machines. It
forms, besides brass, the yellow copper, or laiton; commonly called
pinchbeck.

Acetic acid readily dissolves zinc. The acetate formed is not altered
by exposure to the air, is soluble in water, and burns with a _blue_
flame. It may be used, therefore, in fire-works, to communicate that
colour to flame. It may be formed very expeditiously, by mixing about
equal parts of sulphate of zinc, and acetate of lead, both being in
solution. The sulphate of lead, which is formed, will precipitate,
and acetate of zinc remain in solution. By evaporation, it is
obtained in crystals. This salt cannot injure any composition of
fire-work, in which it enters; as it does not deliquesce, and, for
that reason, may be advantageously employed.

When zinc is used in fire-works, it should be remarkably fine.
The powder may be very readily formed, by heating it, until it is
about to fuse, and pulverizing it while hot, in a warm mortar. It
is generally considered, however, that the best method of obtaining
the powder of zinc, although a longer time is required, is by filing
it; but the filings are more or less coarse, according to the file
which is used. They may be sifted, and thus obtained of any degree of
fineness. In various blue lights, in the blue flame of the parasol
and cascades, and other descriptions of fire-works, it is used. It
gives a more brilliant light than any other substance used for this
purpose. It is frequently mixed with other substances; but, as to its
peculiar properties, they remain the same. By the combustion of zinc,
which follows in fire-works, it always produces an oxide. In this
state, it is expelled, or thrown off.

Acetate of zinc appears to possess advantages over zinc-filing,
especially as it produces the same colour, may be more readily mixed,
and with more accuracy, and does not deliquesce or absorb moisture,
a circumstance which must always be guarded against in artificial
fire-works.

_Sec. XLIII. Of Brass._

This is a mixed metal, composed of copper and zinc. This alloy,
according to the proportion of the metals, is more or less yellow,
or reddish-yellow. The yellow copper, or _laiton_ of the French, the
similor, Manheim gold, prince Rupert's metal, &c. are alloys of the
same metals.

Zinc readily unites with copper; and the usual manner of forming
brass by brass-founders, is to make a direct union between the two
metals. The process, however, generally consists in mixing together
granulated copper, calamine, or carbonated oxide of zinc, and
charcoal in powder, and melting them in a crucible. The charcoal
reduces the zinc, which then unites with the copper. The heat is kept
up for five or six hours, and towards the last of the process, is
raised. Zinc, in small proportion, renders copper pale, and in the
proportion of one-twelfth, inclines its colour to yellow. The yellow
colour increases in intensity with the zinc, until the weight of this
metal in the alloy equals that of the copper. An increase of zinc,
afterwards makes the alloy white. English brass contains one-third
of its weight of zinc. In Germany and Sweden, the proportion of zinc
varies from one-fifth to one-fourth of the copper. Twenty to forty
parts of zinc, with eighty to sixty parts of copper form the _cuivre
jaune_, laiton, or yellow copper of the French.

Dutch metal, or Dutch gold, is a fine kind of brass, and comes in
leaf, which is about five times as thick as gold leaf. This brass is
made by the cementation of copper plates with calamine, and hammered
out into leaves.

According to Thenard (_Traité de Chimie_, tome i, p. 478), the
French use 50 parts of calamine, mixed intimately with 20 parts of
charcoal, and stratified in a crucible with 30 parts of laminated, or
granulated copper. British brass consists of two parts of copper, and
1-1/8 parts of zinc, by weight.

The filings of brass are much employed in fire-works. They
communicate to stars, rains, &c. a flame between a blue and green. In
some, the filings of copper alone are used. A beautiful green fire,
for instance, is produced by 16 ounces of gunpowder, and 3-1/4 ounces
of copper-filings. Verdigris is also employed for the same purpose;
but the effect is not so striking, as in that preparation, the copper
is already oxidized. The effect of copper in fire-works, it is to be
recollected, depends, like that of other metals, on its combustion,
and consequent oxidizement. The product of the combustion of brass,
is oxide of copper, and oxide of zinc.

_Sec. XLIV. Of Bronze._

The union of copper with tin, in various proportions, forms
gun-metal, bell-metal, the mirrors of telescopes, and bronze.

The ductility of the copper is diminished by the tin; but its
hardness, and tenacity, as well as its fusibility and sonorousness
are increased.

To form a complete union of the two metals, they should be continued
in fusion for some time, and constantly stirred. The tin is apt to
rise to the surface, unless this precaution is used.

Bronze is usually composed of 100 parts of copper, and 8 to 12 parts
of tin. It is yellow, brittle, heavier than copper, and has more
tenacity.

The same metals, and in the same proportion, constitute gun-metal.
In the brass ordnance made at Woolwich, the proportion of tin varies
from 8 to 12, to the 100 parts of copper. The purest copper requires
the most. That the alloy is more sonorous than iron, is evident from
the report of brass pieces, being louder than that occasioned by iron
guns.

When the alloy is 78 of copper and 22 of tin, it is chiefly used for
clocks. There is, in the English metal, about five per cent. of zinc,
and four per cent. of lead. The proportion of tin, in bell-metal,
varies. In church bells, less tin is used than for small bells. In
the latter, zinc is sometimes added.

The _Tam-tam_, or _gong_ of the Chinese, used for cymbals, clocks,
mirrors, &c. contains, according to analysis, 80 parts of copper, and
20 parts of tin. The proportions, however, are not always the same.

The ancients made cutting instruments of an alloy of copper and tin.
A dagger, analyzed by Mr. Hielm, consisted of 83-7/8 copper, and
16-1/8 tin. Vessels of bronze were frequently covered with silver.
Some of this kind were found in the ruins of Herculaneum.

Pliny observes, that ancient mirrors were made with a mixture of
copper and tin; but that, in his time, those of silver were so
common, that they were even used by the maid servants. The quantity
of tin, to make the most perfect speculum, depends on the quality of
the copper. If the proportion of tin be too small, the composition
will be yellowish; if it be too great, the composition will be of
a grayish-blue colour. Mr. Edwards casts the speculum in sand with
its face downwards; takes it out while red-hot, and places it in
hot wood-ashes to cool, otherwise it would break in cooling. The
mixture is first granulated, by pouring it into water, and then
fused a second time for casting. Mr. Little recommends the following
proportions: 32 parts of the best bar copper, 4 parts of brass, or
pin wire, 16-1/2 of tin, and 1-1/4 of arsenic.

Whether for speculum metal, bronze, or gun-metal, the metals must be
mixed exactly, and for this purpose be kept a long time in fusion,
and constantly stirred; otherwise, the alloy will not be of a uniform
quality, as the greater part of the copper will sink to the bottom,
and the greater part of the tin rise to the surface. When we speak of
_brass guns_, as that name is generally applied to them, we are to
understand, that they are not made, like brass, of an alloy of copper
and zinc.

The ancient metallic mirrors, which were in use before the present
mirrors, or the discovery of glass, and the mode of applying to its
surface an amalgam of tin, were composed of two parts of copper and
one part of tin. Mr. Mudge asserts, that the best proportion for
mirrors is 32 parts of copper and 14.5 parts of tin. Klaproth found
a specimen of ancient mirror to consist of 32 of tin, 8 of lead,
and 62 of copper. The alloys of copper and tin may be decomposed by
dissolving them in an acid, the muriatic for instance, and immersing
a sheet of iron, which will precipitate the copper. The tin may then
be separated by immersing a plate of lead, or zinc, by either of
which metals, it will be precipitated.

Bronze, being a mixed metal, in which the copper forms the principal
ingredient, is sometimes used in fire-works, in lieu of copper or
brass; for its effects are similar. By the combustion of bronze
filings, we have an oxide of copper and an oxide of tin.

_Sec. XLV. Of Mosaic Gold._

This name, or _aurum musivum_, was given to a preparation of tin,
composed of tin and sulphur. It is considered to be a persulphuret of
tin.

Several methods are recommended for preparing this substance. The
oldest process is to sublime a mixture of 12 parts of tin, 7 parts of
sulphur, 3 parts of mercury, and 3 parts of sal ammoniac. It may be
formed by heating together in a retort, a mixture of equal parts of
sulphur and oxide of tin.

It is used principally for rubbing the cushions of electrical
machines, and for bronzing wood. In fire-works, it is sometimes
employed under the name of _gold-powder_.

It was supposed to be a combination of sulphur with the oxide of tin.
Dr. J. Davy (_Phil. Trans._ 1812, p. 199) and Berzelius, (_Nich.
Jour._ xxxv, 165), have proved, however, that it is nothing more than
metallic tin and sulphur; the proportions of which, according to the
former, are 100 of tin + 56.25 of sulphur.

Mosaic gold is of a yellow colour, resembling that of gold. It is
insoluble in water, and is not acted upon by muriatic or nitric acid.
The nitromuriatic, however, decomposes it. A solution of caustic
potassa dissolves it, forming a green solution, which is decomposed
by acids, letting fall a hydrosulphuret of tin. It deflagrates with
nitre.

When it is used in fire-works, it is pulverized, and sifted. It is
more generally employed as a pigment to impart a golden colour to
small statues of plaster-paris. When mixed with melted glass, it is
said to imitate lapis lazuli.

_Sec. XLVI. Of Iron and Steel._

Both iron and steel are used abundantly in fire-works. It would be
unnecessary to detail the preparations, in which they are employed,
which may be seen by a reference to the different kinds of fire, and
to their respective formulæ.

Cast iron is more employed in artificial fire than forged iron
or steel, at least in the preparation of some, as gerbes, white
fountains, and Chinese fire.

The filings of iron and steel may be sifted through sieves. A fine
hair sieve will answer for common purposes. Their fineness depends,
in the first instance, on the file, which is used. Steel or iron
filings are more commonly employed in the compositions for brilliant
fire.

The sparks produced by cast-iron are very brilliant; but the
reduction of the iron to powder, or to a degree of fineness
sufficient for use, is a difficult operation. It is of too hard a
nature to be cut by a file.

This operation is generally performed in the following manner:
Procure from an iron foundry, some thin pieces of cast iron, such as
generally run over the mould at the time of casting, and pound them
on a block, made of cast iron, with an iron hammer of four pounds
weight, putting, under the block, a cloth to catch the pieces of
iron, which fly off. They are beaten with the hammer in this manner,
until the whole is reduced to grains, which are more or less small.
It is then thrown into a sieve, which should be fine, and the dust
separated. This is used, in the place of steel dust, in small cases
of brilliant fire. The remainder is then put into a sieve, a little
coarser, and again sifted. This portion is preserved separately. The
same operation is repeated, but with sieves of different sizes, till
the iron passes through about the bigness of small bird shot.

The pulverization may be effected in an iron mortar, with a steel
pestle, having the mortar covered in the usual manner, to prevent the
escape of the finer particles of the iron.

According to a writer in the _Dictionnaire de l'Industrie_, vol.
iii, p. 34, the Chinese prepare their iron-sand for fire-works by
igniting iron, and plunging it in cold water. They then pulverize the
scales thus formed, and pass the powder obtained, through different
sized sieves, which is then called No. 1, 2, 3, 4, &c. as it is
very fine or coarse. This cannot be a good method, and we doubt
whether it is at present employed; because it is obvious, that the
scales, in this case, consist of the metal in the state of protoxide.
D'Incarville, a missionary at Pekin, obtained the process for making
Chinese fire; and observes, that the pulverized cast iron they employ
is called _iron-sand_, of which they have six numbers or varieties.

As the goodness of iron or steel dust, in fire-works, depends greatly
on its being dry, and not oxidized or rusted; its preservation must
be accordingly attended to. The usual preservative is to put it in
a box, lined with oiled paper, and covered with the same, or in tin
cannisters, with their mouths well closed.

When it is to be used, it is taken according to its size, and in
proportion to the cases, for which the charge is intended. Large
gerbes, of 6 or 8 lbs. require only the coarse sort.

As the brilliancy of the sparks, produced by the iron and steel dust,
is a desideratum in the formation of some fire-works, and as this
brilliancy depends upon the nature and quality of the metal, it may
not be improper to offer some remarks on these subjects.

That iron, when finely divided is capable of producing sparks of
fire, is a well known fact; and we see it daily in the operations
of the smith, when ignited iron is hammered on the anvil. The
scintillation produced by the steel, when struck with a flint, is of
the same character. In the latter case, the metal is actually fused,
and, when caught on a paper, and examined with a microscope, will
appear globular, and partly oxidized. Hence it is, that gunpowder is
inflamed by this spark, which is nothing more than highly ignited,
and inflamed iron, possessing a temperature more than sufficient to
inflame gunpowder.

The effect, therefore, that results from the inflammation of
fire-works, in which iron or steel forms a constituent part, is
nothing more than a vivid combustion of the metal; and during that
process it becomes oxidized, as it does not form an acid with oxygen,
like arsenic, antimony, and some other metals.

The combustion of iron or steel may be shown by a very brilliant
experiment, that of burning it in oxygen gas. A steel wire,
harpsichord wire for instance, formed into a spiral, with a small
piece of wood dipped in sulphur, stuck on its end and then set on
fire, upon being immediately introduced into a bottle, containing
pure oxygen gas, will burn with great brilliancy, emitting a number
of sparks or scintillations, which fall like rain. In making the
experiment, some sand should be put into the bottle to prevent the
sparks from breaking it. This experiment illustrates the rapid
combustion of iron, or steel. For the oxygen gas supports the
combustion; and while the oxygen is actually taken up by the metal,
which becomes oxidized, and therefore increased in weight, in the
same manner as it does when inflamed in fire-works, the caloric, the
other constituent of oxygen gas, is given out in a free state, and,
with the light at the same time evolved, produces the phenomena of
combustion.

Many other experiments might be mentioned, in which the same effects
take place, and from which the same conclusions may be drawn. But
with respect to the _effect_, whether it be dull, brilliant, or
very brilliant, depends more on the quality of the metal, than
perhaps, on its subsequent mixture with the other materials. Crude
iron, usually called cast iron, seems to possess this property in
an eminent degree; but in the experiment with oxygen gas, steel is
always preferable, as the combustion is more rapid, and the effect
more striking. The difference, which we will not attempt to explain,
may depend on the _state_, as well as the _proportion_ of carbon,
which enters into crude iron, as well as steel. In one case, the
combustion ensues in contact with nitre, and in atmospheric air; in
the other, in contact only with oxygen gas. Be this as it may, this
inference is conclusive, that, in all cases of the combustion of iron
in fire-works, the metal itself unites with oxygen, and the result of
the combustion is an oxide of iron; and with respect to the carbon,
in both instances, it is converted alike into carbonic acid. So that
whether the iron receives its oxygen from the nitre, or from the air,
or from both, is immaterial, as the products are the same.

When iron is exposed to the atmosphere, it tarnishes, and is
gradually changed into a brown or yellow powder, called rust. This
change is owing to its combination with oxygen; and its affinity
for oxygen is such, that, when the vapour of water is made to pass
through an ignited gun-barrel, it is decomposed, the metal becoming
oxidized, and the hydrogen, the other constituent of the water, being
liberated in the form of gas.

Gun barrels are browned by a process of oxidizement. There are
several processes recommended. One of which is, to rub the barrel
over with diluted nitric or muriatic acid, and then, to lay it by
for a week or two, until a complete coat of rust is formed. A brush,
made of iron wire, is then applied; afterwards, oil and wax, and
the barrel is finished by rubbing it with a cloth. The gunsmiths in
Philadelphia use a mixed solution of sulphate of copper, tincture
of the muriate of iron, and sweet spirit of nitre. This they apply
by means of a cloth. The object is to form a rust, and to render
it permanent on the barrel by hard friction along with wax. When
sulphate of copper is employed, metallic copper is precipitated
on the barrel. A coat of rust, put on in this manner, prevents
effectually the oxidizement of the iron; and in point of utility, and
the saving of labour in polishing and keeping muskets in order, the
browning of barrels is certainly advantageous in the land service.
At sea, in particular, where iron is more readily oxidized, this
plan ought always to be adopted. With regard to the use of dragon's
blood, it is entirely too temporary in its effect to be depended on.
I was informed by an intelligent gunsmith, who followed the practice
of browning barrels in Europe, that he has known the _browning_ to
remain very perfect for years, and that the best mode of insuring its
durability is to use the _steel brush_, which _carries in_, as he
expressed it, the rust.

The oxides, which are formed by the union of oxygen with iron, are
two; namely, the black and the red; the first being the protoxide,
and the last the peroxide. The black oxide, which is formed by
the combustion of iron, and by other processes, contains 56 iron
+ 16 oxygen. The common rust of iron is the peroxide of this
metal, combined with carbonic acid. It may be formed by exposing
the protosulphate of iron, or green vitriol, in solution, to the
atmosphere, and then adding an alkali. This oxide contains more
oxygen than the preceding; it consisting of 56 iron + 24 oxygen.

The tempering of cutting instruments, an operation which requires
great delicacy and exactness, after that of hardening, is intended
to obtain a fine and durable edge; and as this subject may be
interesting in a military point of view, we deem the following
remarks of use.

The hardening of steel instruments is performed by heating them to
a cherry-red, and then immersing them in cold water. The tempering
is another process, calculated, as we observed, to obtain a fine
and durable edge. This is performed by heating oil to a certain
temperature, and plunging the instrument into it, where it remains
until the colour appears, indicative of the particular kind of
temper which is intended to be given. The experiments of Stoddart,
(_Nicholson's Quarto Journal_, iv, 129,) are conclusive on this
subject; for his experiments prove, that, between 430° and 450° the
instrument assumes a pale yellowish tinge: at 460° the colour is a
straw-yellow, and the instrument has the usual temper of pen-knives,
razors, and other fine edge tools. The colour gradually deepens as
the temperature rises, and at 500° becomes a bright brownish metallic
yellow. As the heat increases, the surface is successively yellow,
brown, red, and purple, to 580°, when it becomes of a uniform deep
blue, like that of watch springs. Before the instrument becomes
red-hot, the blue changes to a water colour, which is the last
distinguishable colour. These different shades are owing to the
oxidizement of the surface of the metal; and the art of ornamenting
_sword-blades_, knives, &c. long practised in Sheffield, depends on
this principle. The general process is, that an oily composition
is used, with which flowers and various ornaments are painted. On
the application of the heat required for tempering it, that part
which was covered with the composition, is not altered, whereas, the
uncovered parts of the blade are changed. These ornaments, when the
paint is removed, have the natural colour of polished steel. When
steel is heated in hydrogen gas, no appearance of the kind takes
place, a fact which shows, that it is owing to the oxidizement of the
metal.

Iron is soluble in the acids. By the assistance of water, it is
acted upon by sulphuric acid; the metal being oxidized, and the
oxide dissolved, while hydrogen gas is evolved. The salt, formed in
this case, is the sulphate of iron, green vitriol, or copperas. With
muriatic, nitric, acetic and other acids, it forms various salts;
and with gallic acid, when the iron is peroxidized, it forms the
pergallate of iron, or common writing ink, and also the bases of
black dye.

Iron unites with carbon, sulphur and phosphorus. Of the sulphurets,
there are two kinds, the protosulphuret and persulphuret. The former
is the magnetic pyrites, and the latter, cubic pyrites, from both of
which, green vitriol is obtained by decomposition. Pyrites, we may
observe, was the original fire-stone, or the _feuer-stein_ of the
Germans, which was used in the place of flint. See _Beckman's History
of Invention_. Iron also unites with some of the metals, forming
alloys. The white iron of the French, (_Fer blanc_,) or tin plate of
the English, is found to be any alloy of tin with iron, as well as a
covering of tin on iron.

Sheet tin, or tinplate which is necessary in the construction of the
apparatus for some fire-works, for canister shot, &c. is made by
immersing sheets of iron, previously freed from rust, into melted
tin. The number of dippings it undergoes, determines, in some
measure, its quality and character.

The union of carbon and iron, forming very important modifications
of this metal, is not only interesting in the military art, as
concerns the metal for cannon, small arms, and fire-works, but also
in relation to the many and highly useful compounds which result.

All the varieties of iron, which are distinguished by artists, under
particular names, we may consider under the following heads: namely;
cast iron, wrought or soft iron, and steel.

Cast or pig iron is the name of this metal, when first obtained from
the ore. The ores of iron are various, and contain a greater or less
quantity of iron, which is either combined with oxygen, or found with
clay, giving rise to two important classes of iron ore, the calciform
and the argillaceous. The reduction of the ore merely requires the
presence of charcoal, and occasionally some addition, as limestone,
when the clay iron ores are to be reduced. On the application of
heat in furnaces, constructed for the purpose, the charcoal unites
with the oxygen of the oxide, reducing it to the metallic state, and
escapes in the form of carbonic acid; and the lime, if the ore be
argillaceous, unites with the clay, forming a kind of glass, which
floats on the melted metal. When the iron is suffered to run into
moulds, prepared for its reception, it usually takes the name of pig
iron.

Manufacturers distinguish cast iron by its colour and other
qualities. The _white cast iron_ is hard and brittle, and can neither
be filed, bored, nor bent. Gray mottled iron, so called from its
colour, is of a granulated texture, softer, and may be cut, bored and
turned on the lathe. Cannon are made of this iron. _Black cast iron_
is the most unequal in its texture, but the most fusible.

Cast iron melts at 130° of Wedgwood. Its specific gravity varies
from 7.2 to 7.6. It is converted into malleable, usually called soft
iron, by a process called refinement. Several modes have been adopted
for this purpose. It was formerly done by keeping it in fusion in a
bed of charcoal and ashes, and afterwards forging it. The hammering
makes the particles of iron approach each other, and expels some
impurities.

Among the various improvements for expeditiously and effectually
converting crude into malleable iron, the process of Mr. Cort seems
to possess advantages. The cast iron is melted in a reverberatory
furnace, and the flame of the combustible is made to act upon the
melted matter. It is stirred during this operation, by which means,
every part is exposed to the air. A lambent blue flame begins to
appear in about an hour, and the mass swells. The heat is continued
about an hour longer; and, by this time, the iron acquires more
consistency, and finally congeals. While still hot, it is next
hammered by powerful tilt-hammers. This is called the _puddling_
process.

Iron, obtained in this way, is not however pure; for it contains
either some of the other metals, or oxygen, carbon, silicon, or
phosphorus.

When small pieces of iron are stratified in a crucible with charcoal
powder, and exposed to a strong heat for eight or ten hours, they are
converted into steel. Steel is brittle, resists the file, cuts glass,
and affords sparks with flint. It loses its hardness by ignition and
cooling. It is malleable at a red heat. It melts at 130 degrees of
Wedgwood. By being repeatedly ignited in an open vessel, it becomes,
by hammering, wrought iron.

Natural steel is that which is formed, by converting the ore first
into cast-iron, and exposing it to the action of a strong heat, while
the melted scoriæ float on its surface. This steel is inferior to
the others. Steel of cementation is formed, on a large scale, by
stratifying bars of iron with charcoal, in large earthen troughs or
crucibles, the mouths of which are closed with clay. These troughs
are put in furnaces, and, in eight or ten days, the process is
finished. This is also called blistered steel, on account of the
appearance of its surface. The tilted steel is that which is beaten
out into small bars by the hammer. When broken, and the pieces again
united by welding in a furnace, and made into bars, it is then called
German or shear steel.

Cast steel is considered the most valuable of all the varieties; and
is used for the manufacture of razors, surgeons' instruments, &c. It
is, besides, more fusible than common steel, and for that reason,
cannot be welded with iron. It is made by melting the blistered
steel, in a close crucible, along with pounded glass, and charcoal
powder. It may also be formed by melting together 30 parts of iron,
1 part of charcoal, and 1 part of glass. Equal parts of chalk and
clay, put with iron in a crucible, will also produce it.

The Celtiberians in Spain had a singular mode of preparing steel.
Diodorus and Plutarch both say, that the iron was buried in the
earth, and left in that situation, till the greater part of it was
converted into rust. What remained, without being oxidized, was
afterwards forged and made into weapons, and particularly swords,
with which they could cut asunder bones, shields, and helmets.
This process is used in Japan, however improbable it may seem;
and Swedenbourg, among the different methods of making steel, has
introduced it. Bishop Watson, (_Chemical Essays_ 8vo. i, p. 220,)
speaks of the same process. The fact has been verified at Gottingen;
for an anvil, which had been buried in the ground for many years,
was found to be extremely soft; and a part of it, which appeared in
steel-like grains, possessed the properties of steel.

The sabres made in Japan, according to Thunberg, are incomparable.
Without hurting the edge, they can be made to cut through a nail at
one blow.

The art of hardening steel by immersion in cold water is very old.
Homer (_Odyssia_ ix, 301,) says, that, when Ulysses bored out the
eye of Polyphemus with a burning stake, it hissed in the same manner
as water, when the smith immerses in it a piece of red-hot iron, in
order to harden it. Sophocles, Salmasius, Pliny, Justin and others
mention the use of water in hardening iron; but the most delicate
articles of that metal were not quenched in water, but in oil. As to
the opinion of the peculiar virtue of any particular water, for the
purpose of hardening iron, which many have believed, it is altogether
fallacious, although Vasari asserts, that the archduke Cosmo, in
1555, discovered a water, that would harden instruments, to cut, like
the ancient tools, the hardest porphyry. The art of working porphyry,
however, was known in every age. Beckman assures us, when treating
of the processes of making steel, that the invention and art of
converting bar iron into steel, by dipping it into other fused iron,
and suffering it to remain there several hours, although ascribed to
Reaumur, (_Art de Convertir le Fer en Acier_, p. 145), are mentioned
by Agricola, Imperati, and others, as a thing well known and
practised in their time.

Pliny, Diamachus, and other ancient writers mention various countries
and places, which, in their time, produced excellent steel. The
_ferrum Indicum_ and _Sericum_ were the dearest kinds. The former is
the same as the _ferrum candidum_, a hundred talents of which were
given, as a present, to Alexander in India.

Beckman thinks, that the ancient _ferrum candidum_ is the same kind
of steel still common in India, and known under the name of _wootz_;
some pieces of which were sent from Bombay in 1795 to the Royal
Society. Its silver coloured appearance, when polished, he thinks,
may have given rise to the epithet of _candidum_.

Mr. Faraday of the Royal Institution has lately examined wootz, and
imitated it very accurately. The experiments may be seen in _Ure's
Chemical Dictionary_, article _Iron_. It appears that the presence of
silex and alumina distinguishes this kind of steel from the English.
Four hundred and sixty grains of wootz gave 0.3 of a grain of silex,
and 0.6 of a grain of alumina. It is highly probable, that the much
admired sabres of Damascus, are made from this steel.

A small portion of silver, melted with steel, improves the latter
very considerably. One part of silver and five hundred parts of
steel were melted together, and every part of the alloy formed, when
tested, indicated silver. The alloy forged remarkably well, although
very hard, and was pronounced to be superior to the very best steel.
This excellence is undoubtedly owing to its combination with the
silver, however small. The alloy has been repeatedly made, and with
the same success. Various cutting tools have been made from it of the
best quality. The silver is found to give a mechanical toughness to
the steel.

Platinum and steel, equal parts by weight, form a beautiful alloy,
which takes a fine polish, and does not tarnish. This alloy is said
to make the best speculum. Steel, for edge tools, is improved by this
metal. The proportions, which appear to be most proper, are from one
to three per cent. An alloy of 10 platinum with 80 of steel, after
exposure for many months, had not a speck on its surface. Would not
this alloy, as it is not oxidized, be very useful for making points
for lightning rods, in lieu of iron, gold, silver, or platinum alone?
The experiment is worth a trial; for nothing adds more to the safety
of a magazine, or building, against the effect of lightning, than a
conductor.

Iron and carbon, it appears, are capable of uniting in different
proportions; hence the variety of crude iron, and the different kinds
of steel. When the carbon exceeds the iron, as in plumbago, or black
lead, it forms a carburet. When the iron exceeds, such compounds are
properly speaking sub-carburets; under which name, we may rank all
the varieties of cast iron and steel.

The hardness of iron, according to the experiments of Mushet,
(_Phil. Mag._ xiii, p. 138), increases with the proportion of
charcoal, with which it combines, until the carbon amounts to
about 1/60th of the whole mass. This is the maximum, the metal
acquiring the colour of silver. More carbon diminishes the hardness,
according to its quantity. The difference in iron, whether it be the
_cold-short_, or _hot-short_ iron, a matter of some consequence to
the workers in this metal, was found to be owing to phosphoric acid
in the cold-short, which exists with the iron. But the substance,
called _siderum_ by Bergman, is a phosphuret, and not a phosphate of
iron.

We have gone into this subject more fully, on account of its
importance, and intimate connection with the casting of guns, and the
different qualities of iron. In fire-works, it will appear obvious,
that the various properties exhibited by iron are owing to the iron
and carbon, to the changes which they undergo, to the combustion
which necessarily ensues, and to the production of oxide of iron,
and carbonic acid gas; effects that invariably take place, whether
cast iron or steel be used, provided it is exposed to the action of
agents, under the same circumstances and conditions.

_Sec. XLVII. Of Glass._

Glass, in the form of powder or dust, is used in fire-works. The
pulverization of glass is easily performed. It may be done in an iron
mortar, and passed though fine wire or brass sieves. It is used in
the composition for wheels, in water balloons, cones, fire-pumps,
slow white fire, &c.

Glass is nothing more than fused silica, made by exposing a mixture
of silica and other substances to the action of a violent heat.

The quality of the glass depends on the proportion of silica, and the
fluxes which are used in promoting its fusion; for the various kinds
of glass, as white glass, green glass, bottle glass, &c. are all, in
one respect, the same, though they differ in these particulars.

The glass of Saint-Gobin in France is made by fusing white sand,
lime, soda, and broken inferior glass. The white goblet-glass is made
of sand, potash, lime, and old glass; the quantity of potash is about
fifty per cent. If green, or yellow, the colour is destroyed by the
addition of black oxide of manganese; and hence that oxide is named
_glass makers' soap_.

The common plate glass, for electrical machines, &c. is formed of
sand, crude soda, old glass, and oxide of manganese. The bottle
glass, made with the soda of marine plants, consists of sand, soda,
common ashes, and old glass. Another bottle glass is made by melting
common sand, black or yellow, with soda, wood-ashes, clay, and
broken glass. It appears from the use of the substances which enter
into, and compose, glass, that its quality is owing to the materials
employed. The crystal or flint glass is a finer kind. The substances,
with the proportions in which they are used, are the following:

_Parts._
White sand, 100
Red lead, 80 to 85
Calcined potash (pearl-ash,) 35 to 40
Refined nitre, 2 to 3
Black manganese, 0.06

To this composition, there are sometimes added:

_Parts._
White arsenic, 0.05 to 0.1
Crude antimony, 0.05 to 0.1

The specific gravity of this glass is 3.2. Goblets, lustres, &c. are
made of it.

Flint glass, according to the English formula, is made of

Purified Lynn sand 100 parts.
Litharge or red lead 60
Purified pearlash 30

To this is added black manganese, to correct the colour, and
sometimes nitre and arsenic.

Plate glass is formed of

Pure sand, 43.0 parts.
Dry carbonate of soda, 26.5
Pure quicklime, 4.0
Nitre, 1.5
Broken plate glass, 25.0
------
100.

Crown, or fine window glass, is composed of

Fine sand, 200 lbs.
Best kelp, ground, 330 lbs.

To this is added, if the vitrification is not complete, some muriate
of soda. Good glass, according to Pajot des Charmes, may be made
by fusing equal parts of carbonate of lime, sand, and sulphate of
soda. The glass is clear, solid, and of a pale yellow. Professor
Scheweigger found, that the following proportions were the best:

Sand, 100
Dry sulphate of soda, 50
Dry quicklime in powder, 17 to 20
Charcoal, 4

Broad glass is made of a mixture of soap-boilers' waste, kelp, and
sand. Two of waste, one of kelp, and one of sand are the proportions
generally employed. Common bottle glass is usually made of waste and
river sand, to which lime, and clay, and common salt are occasionally
added.

The coloured glasses are produced by various metallic oxides. The
colour and beauty of precious stones are thus imitated. These colours
are communicated by sundry metallic preparations, as the following:
The purple powder of Cassius, with oxide of manganese, will give a
red or purple according to the proportions used; zaffre, an oxide of
cobalt, a blue; a mixture of oxide of cobalt, muriate of silver, or
glass of antimony, a green; and oxide of manganese, a violet, &c.

The basis of all artificial precious stones, is composed of what is
called glass-paste, a compound of silica, potash, borax, red lead,
and sometimes arsenic. These substances are melted together. The
glass, which forms the body of the artificial gem, is pulverized, and
the colouring substances are blended with it by sifting; and then the
whole must be carefully fused, being left on the fire for from 24 to
30 hours, and cooled very slowly. The following proportions are used
for this purpose:

_Pastes._ 1. 2. 3. 4.
Rock crystal, 4056 gr. ---- 3456 360
Minium, 6300 ---- 5328 ----
Potash, 2154 1260 1944 1260
Borax, 276 360 216 360
Arsenic, 12 12 6 ----
Ceruse of clichy, -- 8508 ---- 8508
Sand, -- 3600 ---- ----

_Topaz._ No. 1, No. 2.
Very white paste, 1008 3456
Glass of antimony, 43 ----
Cassius purple, 1 ----
Peroxide of iron, (saffron of Mars,) -- 36.

_Ruby._ Paste 2880, oxide of manganese 72.

_Emerald._ Paste 4608, green oxide of copper 42, oxide of
chrome 2.

_Sapphire._ Paste 4608, oxide of cobalt 68, fused for 30
hours.

_Amethyst._ Paste 4608, oxide of manganese 36, oxide of
cobalt 24, purple of Cassius 1.

_Beryl._ Paste 3456, glass of antimony 24, oxide of cobalt
1-1/2.

_Styrian garnet_, or ancient carbuncle. Paste 512, glass of
antimony 256, Cassius purple 2, oxide of manganese 2.

The following recipes are given by M. Lancon:

_Paste._ Litharge 100, white sand 75, potash 10.

_Emerald._ Paste 9216, acetate of copper 72, peroxide of
iron 1.5.

_Amethyst._ Paste 9216, oxide of manganese from 15 to 24,
oxide of cobalt 1.

The ancient coloured glass has been much admired. The art was carried
to a very great extent. Even in Pliny's time, the highest price was
set upon glass entirely free from colour. He, as well as others,
mentions that hyacinths and sapphires were imitated very exactly.

The emperor Adrian received as a present from an Egyptian priest,
several glass cups richly ornamented with various coloured glass.
Seneca speaks of the knowledge of Democritus in this art. Porta,
Neri, and others, in modern times, have treated the subject in a
more enlarged manner. Coloured glass was used for ornament; but
Pollio relates, that Gallenius punished an impostor for selling to
his wife a piece of glass for a jewel. In the _Museum Victorium_ at
Rome, are several ancient artificial gems, such as the chrysolite and
emerald. What materials the ancients used for colouring glass is not
known. Gmelin, however, observes, that it is probable they made use
of iron, by which, he adds, not only all the shades of red, violet
and yellow, but even a blue colour might be communicated. Cassius
discovered the powder which bears his name. He was a physician, and
resided at Lubec.[22] This powder was employed by the German artists.
While noticing this subject, it may be proper to state, that Libavius
(_Alchemy_, 1606,) gives a process for making ruby glass. Neri, (_ars
vitraria_ by Kunkel,) was acquainted with the gold-purple and its
use. Glauber (_Furnus Philosophicus_, 1648) mentions the use, and
gives the preparation of the powder. Kunkel made artificial rubies in
great abundance, and a cup of ruby glass for the elector of Cologne.
In 1679, he was inspector of the glass houses at Potsdam; and, in
perfecting the art, he expended 1600 ducats, which the elector of
Brandenburgh gave him for the purpose.

M. Brongniart has lately made many experiments on the subject of
staining glass. The colours, however, are the same as we noticed. A
green glass may be made by putting on one side of the glass a blue,
and on the other a yellow. A black glass may be made by a mixture of
blue with the oxides of manganese and iron. Painting on glass is an
ancient art. When pieces of old painted glass are examined, they have
always on one side a transparent red _varnish_ burnt into them. The
moderns, however, excel in this art.

Glass is not acted upon by the acids, except the fluoric or
hydrofluoric. Hence the acid of Derbyshire spar, which is a fluate of
lime, is used for etching on glass, in the same manner as nitric acid
is, on copper. Fluoric acid, a compound of fluorine and hydrogen, is
decomposed during this action, and is changed, by the union of its
fluorine with silicon, into the silicated fluoric acid.

When a quantity of alkali is used just sufficient to fuse silica,
glass is the result; but when the quantity is greater, as three or
four to one, the fused mass is soluble in water, and then forms
the silicated alkali, or liquor of flints. From this the silica is
obtained in a pure state, by the addition of an acid.

Glass, when melted and dropped into water, assumes an oval form, with
a slender projection, called a tail. This is called Prince Rupert's
drop. If a small part of this tail be broken off, the whole bursts
into powder, with a kind of explosion. The Bologna, or philosophical
phial, is a small cylindrical vessel of glass, rounded at the bottom,
but open at the upper end. It is made thick at the bottom, so as
not to be easily broken; but if a pebble be dropped into it, it
immediately cracks, and the whole falls into pieces. In both these,
(the drop and the bottle,) the glass is unannealed. When the external
part of glass is suddenly cooled, the inner part is kept, as it were,
contracted. Now annealing, the process of tempering glass in an oven,
renders the glass uniformly alike, and capable of sustaining the
variations of temperature, without breaking. By a crack or fissure,
the internal parts which remained in a state of tension, endeavour to
recover the full state of expansion, and consequently the glass is
rent asunder.

_Sec. XLVIII. Glue and Isinglass._

Both glue and isinglass are animal products. They are used in
fire-works, but always in the state of solution, as vehicles to
mix up compositions in order to make them unite, and to preserve
them from falling to powder. The quantity, however, is never large,
or either would destroy the effect. The proportions are generally
prescribed. A solution of glue is employed in the old process for
refining saltpetre. See _Nitre_. In making priming paste, isinglass
dissolved in brandy is sometimes used.

Glue and isinglass owe their adhesive quality to the presence of
gelatin; the most remarkable property of which is, that it unites
with, and precipitates the tanning principle from its solution in
water. For this reason, the use of oak bark and other astringent
substances, in the tanning of leather, is obvious, the gelatin of the
hide or skin, uniting with the tannin and forming tanned leather.
Gelatin exists in bones, muscles, tendons, ligaments, membranes and
skins. Skins, especially those of old animals, furnish the best and
strongest glue.

For the preparation of glue, the parings and offals of hides, pelts,
and the hoofs and ears of horses, oxen, calves, sheep, &c. are first
digested in lime-water to clean them; then steeped in fresh water,
which is suffered to run off; and being previously inclosed in a
strong linen bag, are boiled in a copper cauldron with pure water.
The impurities are removed as they rise. To the solution, alum, or
finely powdered lime, is added. It is then strained through baskets
and allowed to settle; after which, the clear fluid is again boiled.
When it becomes thick, or of a proper consistence, it is poured into
moulds or frames, when it concretes into jelly. It is cut into pieces
by a spade, and then into thin slices by means of wire, and finally
dried on coarse net-work.

The goodness of glue is known by its brittleness, and equal degree of
transparency, without black spots. It swells up in cold water, and
becomes gelatinous, but does not dissolve. It is a mark of want of
_strength_, when glue dissolves in cold water.

Size is also a gelatinous substance, and is colourless and
transparent. Eel skins, vellum, parchment, &c. are used in its
preparation. They are treated in the same manner as hides. Isinglass,
or fish glue, is a finer kind of gelatin, obtained from the air
bladder and sounds of different kinds of fish of the _accipenser_
genus; as the _sturio stellatus_, _huso ruthenses_, _&c._ The
bladder, when taken from the fish, is washed and stripped of its
exterior membrane, and then cut lengthwise and formed into rolls, or
cut into strips. Isinglass dissolves in water with more difficulty
than glue. A coarser kind of fish glue is made from sea wolves,
porpoises, sharks, cuttle fish, the sturgeon, &c. The head, tail,
fins, &c. are boiled in water, and the solution evaporated. Isinglass
is used for a variety of purposes, as the making of court plaster and
size, the clarification of liquors, &c.

Isinglass is almost wholly gelatin. One hundred grains give
ninety-eight of soluble matter.

Gelatin constitutes the greater part of the solid parts of animals,
such as bone, ligament, muscle, membrane, skin, &c. and is always
extracted by boiling them in water. We need hardly remark, that
it constitutes the chief part of soup, which owes its nutritive
qualities principally to its presence. The portable soup is nothing
more than concrete gelatin, with other substances, as spices, salt,
&c.; for it contains, in a small compass, the nutritive parts of
beef, veal, and other animal substances, from which it may have been
prepared.

Besides the use of water for extracting, or otherwise separating, the
gelatin from bone, we may separate the phosphate of lime entirely
from the latter, (as these two substances constitute the greater part
of bone), by the action of dilute muriatic acid, which will dissolve
the phosphate of lime, and leave the gelatin.

_Sect. XLIX. Of Wood._

Of the kinds of wood, used for the preparation of coal, for the
purpose of gunpowder, those should be preferred, which are light, and
will give a tender charcoal. This subject was fully considered under
that head.

But our intention, in noticing wood at this time, is, that it is
employed in the composition of some fire-works in the form of
saw-dusts, or raspings. Its use in fire-works may be considered,
1st, as producing a particular coloured flame: 2dly, as varying the
character of the flame, and likewise the degree of the combustion;
and 3dly, as communicating an agreeable odour along with other
substances; as in odoriferous fire-works. To this, we may add its use
in smoke-balls along with nitre and sulphur.

The raspings of wood are sometimes required to be extremely fine.
This can only be done by employing sieves of different degrees of
fineness. They should be preserved from the action of moisture.

In the composition of the new priming powder, of which chlorate of
potassa is the basis, very fine raspings of a particular kind of
wood are employed. So is also lycopodium for the same purpose.

By the distillation of wood, as in the process of carbonization
in iron cylinders, we obtain some volatile products, the chief of
which is the pyroligneous, now called the pyroacetic acid, while the
ligneous fibre is converted into coal; but, in the combustion of
wood, all the volatile products are expelled, some being consumed in
the flame, and others, with some carbon, condensed in the form of
soot, while the residue is an ash which furnishes common potash.

Ovid in his Metamorphoses, fable xvi, says--"Adomitis Athamanis aquis
accendere lignum narratur; minimos cum luna recessit in orbes."
This idea we know is groundless; for it is impossible, that wood,
sprinkled with water, whether the waters of Athamanis, or any other,
should be kindled when the moon is in the decrease, or at any time of
the moon's age.

To prevent the action of fire on wood, marine salt, vitriol, and
alum have all been used. Various ways of employing them have been
adopted; but they do not absolutely prevent wood taking fire in an
active heat. For the same purpose, (_Coll. Academ._ tome xi, p. 487,)
a mixture of green vitriol, and quicklime is recommended, by which
we form sulphate of lime and oxide of iron. The _Journal de Paris_
of 1781 contains various processes. At Vienna, saline substances are
employed.

The combustion of wood is the same, in all cases, in which oxygen
is concerned; but the products in some particulars may vary. Hence
saw-dust, when mixed with nitrate of potassa, and inflamed, will
burn, and produce little or no smoke, because the combustion is rapid
and perfect; but when employed with sulphur and nitre, it produces
much smoke. Here the oxygen is furnished by the nitre, and carbonic
acid gas is formed. The same thing takes place, when a mixture of
saw-dust and nitre is used in artificial fire; and, according as
the decomposition is more or less rapid, the combustion will be so
likewise. The particular applications of saw-dust will be noticed
hereafter.

With respect to _lycopodium_ or puff ball and various species of
agaric, or the medullary excrescences of trees, which are used in
some preparations of artificial fire, we may observe, that the first
is confined principally to theatrical fire-works, and the second
to the preparation of spunk, or tinder, called also pyrotechnical
sponge. See _Pyrotechnical Sponge_.

As to the substance usually called _lightning wood_, found in the
hollow of the stumps of trees, and sometimes on the surface, which,
from having lost its compactness and other characters of ligneous
fibre, is called _rotten_ wood, it is in fact the solid part of the
wood in a state of decomposition, in consequence of which, it becomes
a _solar phosphorus_. It appears to owe its phosphorescent property,
i. e. its power of shining in the dark, to the previous absorption
of light, and not, as some have suggested, to the presence of
phosphorus, or the emission of any gaseous compound, which contains
it. The process of animal putrefaction will produce such appearances,
but, in this case, the cause is different.

Turf or peat, a substance found, and employed as fuel, in some
countries, and found in boggy situations, is partially decomposed
vegetable matter, consisting of a congeries of fibres or roots. But
black mould is the result of a decomposition of vegetable substances,
in which the ligneous fibre is carbonized, and mixed with earth. The
formation of mould, however, is owing more to the decay of leaves &c.
(See _Coal_.)

Dr. Shaw (_Travels to the Holy Land_) observes, that when they were
either to boil or bake, camel's dung was their common fuel; which,
after being exposed a day or two in the sun, catches fire like
touch-wood; and burns as light as charcoal.

_Sec. L. Of Linseed Oil._

Linseed, or flaxseed, oil is obtained by expression from flaxseed.
It is a thick mucilaginous oil, when first extracted, called _raw_
oil, and in this state, is seldom used. The preparation, it undergoes
before it is used as drying oil for mixing with paints, is nothing
more than boiling it with litharge, or some oxide of lead, which
separates the mucilage, and unites with the oil. By this treatment,
it acquires the property of drying with facility, when exposed to the
atmosphere.

Linseed oil unites with great ease with oils, tallow, fat, wax, &c.
Some of these compositions are used in fire-works. A preparation
of pitch, mutton suet, and linseed oil is used, for instance,
in preventing the access of moisture to fuses; and in military
fire-works, it is employed in combination with pitch, rosin, mutton
suet and turpentine for incendiary works. Wax, and tallow, we may
here add, are also used in the preparations of similar works.

_Sec. LI. Of Gum arabic, and Gum Tragacanth._

Gum arabic, which exudes from a tree that grows in Egypt and Arabia
(_Mimosa nilotica_) when pure is transparent, and nearly colourless.
There are several varieties of this gum; the _gum senegal_, for
instance, which is of a reddish colour, and occurs in larger pieces.
Other mucilaginous substances, the peach tree gum, the cherry tree
gum, &c. which exist only in small quantities, are analogous to the
gum of the Mimosa.

Gum arabic is brittle, and for that reason may be easily reduced
to powder. It is readily dissolved in water, with which it forms
mucilage. In this state, it is employed in fire-works, chiefly as a
vehicle for the mixing of pastes, matches, &c.

Gum is a vegetable oxide, composed of carbon, hydrogen, and oxygen.
It does not crystallize. It is precipitated by some metallic salts,
as acetate of lead. It is insoluble in alcohol, which distinguishes
it from resins. Nitric acid decomposes it, and changes it into the
saclactic or mucous acid. With sugar, the same acid produces oxalic
acid.

Gum tragacanth, or gum dragon, is the produce of a thorny shrub,
which grows in Candia, and other islands of the Levant, called
_astragalus tragacantha_. The gum obtained from this shrub has many
properties in common with gum arabic, and is, therefore, used as a
paste. It dissolves readily in boiling water; but is insoluble in
alcohol, or ether.

It consists, almost entirely, of a peculiar vegetable principle,
which is called _cerasin_ by Dr. John. Cerasin has the adhesive
qualities of gum arabic, but in a greater degree. It is said to
constitute a part of the gummy matter, that exudes from the _prunus
cerasus_, _prunus avies_, _prunus domestica_, &c.

_Sec. LII. Of Cotton._

The soft down, which envelopes the seeds of different species of
_gossypium_, or cotton plant, is the cotton of commerce. These plants
are natives of warm climates. Cotton when bleached is perfectly
white. It is extremely combustible, and burns with a clear lively
flame. The ashes left behind contain potash.

Cotton is the substance, usually employed in making match rope, for
the communication of fire. It has also other uses in pyrotechny.
Cotton match is much used in fire-works for exhibition, not only for
single cases, but also for a series of cases of artificial fire,
either for fixed or moveable pieces; and serves to communicate fire,
either singly, or from one case to another, or to the whole piece
at one time. Matches, so used, are called leaders, and are generally
confined in paper tubes.

Cotton is one of the best applications to recent burns. Applied to
the part, it will, in a surprising manner, abate the violence of the
pain, and remove the inflammation.

Cotton is soluble in alkaline ley. For some of the earths, it has a
strong affinity, particularly alumina; as also for several metallic
oxides, and tannin. The action of mordants, in dying of cotton-goods,
depends on these affinities. Nitric acid converts it into oxalic acid.

Cotton wick for lamps, candles, &c. is rendered very inflammable by
spirit of turpentine. By dipping the end of the wick in turpentine,
the candle will inflame at once, the moment flame is applied. For
candle-making, the wick is sometimes dipped in a solution of camphor
in spirits, or in a melted mixture of camphor and wax. See _Candle_.

_Sec. LIII. Of Bone and Ivory._

Bone, which is considered to be a combination of phosphate of
lime, gelatinous matter, animal oil, &c. is used occasionally in
fire-works. By destructive distillation, bones, or osseous matter,
afford ammonia, Dippel's animal oil, &c.; and, when consumed by
fire, leave a white ash, which is composed principally of phosphate
of lime. Bone-ash is the result of the combustion of bone; for,
while all the gelatinous substance, oil, &c. are burnt off, that,
which composes the basis of bone, and which distinguishes it from
_gristle_, remains in the form of ash. Bone-ash furnishes phosphorus
by a certain process. See _Phosphorus_. Diluted muriatic acid will
take up the phosphate of lime of bone and leave the gelatin. This
mode is recommended for the separation of gelatin from bone.

Bones, when carbonized in the same manner as wood, furnish what is
called _bone-black_, but commonly known by the name of _ivory-black_.
It is nothing more than animal charcoal.

In Pyrotechny, bone, in the form of raspings, is employed to
communicate a _lustre_ to the flame of gunpowder; but, for this
purpose, the most compact, and that, which contains the least
gelatin, is usually employed. Hence _ivory_ is preferred. Ivory, in
the form of raspings, communicates to flame a bright silver colour;
and, on that account, is preferred to all other kinds of bone. The
compositions, into which it enters, will be mentioned in a subsequent
part of the work.

Ivory is the tusk, or tooth of defence, of the male elephant, and is
an intermediate substance between bone and horn, not capable of being
softened by fire. The finest and whitest ivory comes from the island
of Ceylon. The tooth of the sea-horse is said to approach to ivory,
properly so called. It is, however, harder, and, for that reason,
preferred by dentists for making artificial teeth. The coal of ivory
is remarkably black; but the so called ivory-black, sold in the
shops, is nothing else than bone-black.

Bone and ivory may be stained of various colours. One hundred parts
of ivory contain,

Gelatin, 24
Phosphate of lime, 64
Carbonate of lime, 0.1

One hundred parts of ox-bone gave

Gelatin, 51
Phosphate of lime, 37.7
Carbonate of lime, 10
Phosphate of magnesia, 1.3

Berzelius, however, detected in bone-fluate of lime, muriate of soda,
and uncombined soda. Albumen is most generally present. One hundred
parts of bone are reduced by calcination to sixty-three. One hundred
parts of human bone afforded Berzelius 81.9 phosphate of lime, 3
fluate of lime, 10 lime, 1.1 phosphate of magnesia, 2 soda, and 2
carbonic acid.

_Sec. LIV. Of Galbanum._

Galbanum is a gum-resin, obtained from the _bubon galbanum_, a plant
peculiar to Africa. It is at first a juicy fluid, which exudes when
the plant is cut above the root, and hardens by exposure to the air.
Alcohol dissolves about three-fifths of it. It contains some volatile
oil.

The only instance we know of, in which galbanum has been used in
fire-works, is in the composition of rain-fire, employed as an
incendiary, before the present _fire-stones_ were invented. The
rain-fire, which may be found in the fourth part of this work, it
is said, gave rise to the composition of fire-stone. There is no
advantage, however, in using galbanum for this purpose; since pitch,
tar, turpentine, and many other substances are more inflammable,
and, therefore, better adapted for such compositions. We mention it
merely because it was one of the ingredients in that once celebrated
incendiary preparation, the fire-rain of Siemienowicz.

_Sec. LV. Of Tow and Hemp._

In military fire-works, tow and hemp are much used, and principally
for the preparation of incendiary works. Both tow and hemp are
employed in forming match. Although old rope, &c. are used for
immersion in the tourteaux, carcass, or fire-stone composition, which
is readily imbibed, if the rope is untwisted and beaten; yet tow or
hemp is a better material, and receives more of the composition. The
manner of using it may be seen by referring to the composition for
fire-stone. For very nice purposes, the tow or hemp should be well
dressed. Flax is, therefore, to be preferred in such cases.

_Sec. LVI. Of Blue Vitriol._

Different preparations of copper are used in fire-works, to
communicate colour to the flame; and besides copper filings, brass
filings, verdigris, and the oxides of copper, the sulphate of copper,
or blue vitriol, has been employed. We may observe here, that there
are three sub-species of this salt; the bisulphate, sulphate, and
sub-sulphate, the first properly speaking being the blue vitriol of
commerce.

The sulphate, although recommended in some of the old formulæ for
coloured fire, is not, however, preferable to some other preparations
of copper. The use and application of copper, and its preparations,
will be seen in the article on coloured fire.

When sulphate of copper is heated, it is converted into a
bluish-white powder. If the heat be increased, the acid is expelled,
and the black oxide of copper remains. Before it is used, it is
exposed to heat to expel the water of crystallization. It ought to
be in the state of impalpable powder. It is composed of 33 acid, 32
oxide, and 35 water. It is decomposed by the alkalies and earths, the
alkaline carbonates, borates, and phosphates, and several metallic
salts.

The oxide may be obtained very readily from this salt, for the
purpose of fire-works, by dissolving it in water, and adding a
solution of caustic potassa; collecting the precipitate, and drying
it in a moderate heat. This will expel the water that may be
contained in it; as metallic precipitates, made in this way, are more
or less in the state of hydrates.

When metallic copper is required, it may be obtained in fine powder,
and very expeditiously, by immersing a plate of iron in a solution
of any of the salts of copper, as the sulphate. It will precipitate
on the iron, and gradually fall to the bottom of the vessel. This
metallic copper will be found to be much more impalpable than the
filings, however fine, and, for that reason, may be mixed more
accurately with different substances.

Copper burns with a beautiful green flame, and deposites a loose
greenish-gray oxide. The ammonia-oxalate of copper, of which there
are three sub-species, burns with flame.

_Sec. LVII. Of Nitrate of Copper._

This preparation of copper is used in some fire-works. It
communicates a green colour to flame. When combined with carbonaceous
substances, the combustion is vivid. This is owing to the
decomposition of the nitric acid, (in the same manner as the acid of
nitrate of potassa and other nitrates is decomposed), during which
carbonic acid and deutoxide of azote are produced. Nitrate of copper
has been more particularly recommended for the preparation of match
stick, similar to that of M. Cadet, and of match rope. It is used in
the same manner as the nitrate of lead. M. Proust used it in lieu of
nitrate of lead when repeating some experiments of M. Born. It is
more expensive than the acetate, or even the nitrate of lead. Its
effect, however, is the same.

Nitrate of copper attracts the moisture of the atmosphere, and
deliquesces. Acetate of lead, on the contrary, by exposure to the air
gradually effloresces, and in time is decomposed. The preparations of
lead, for that reason, are preferable to the nitrate of copper.

Nitrate of copper is formed by dissolving copper in nitric acid; and,
when the acid is saturated, the requisite quantity of water may be
added. The salt may be obtained in a dry state by evaporation; and,
after being dissolved in water, the wood or rope may be soaked in it.

Dry nitrate of copper, wrapped up in tin-foil, will produce no
action; but, if water be added, sufficient to moisten it, and then
the foil closed tightly, combustion will take place. The water
promotes chemical action by dissolving the nitrate of copper, which
is then decomposed by the tin, and the quantity of caloric, put in a
distributable state, is sufficient to inflame the tin. The details of
the rationale will be given hereafter.

The ammonia-nitrate of copper is fulminating copper. The chlorate of
copper is a deflagrating salt. Ammonia added to nitrate of copper,
first separates an oxide, and then dissolves it. It is more than
probable, that nitrate of ammonia causes the ammonia-nitrate to
explode.

_Sec. LVIII. Of Strontia._

The earth called strontia or strontian, is found abundantly in
different parts of the world, in combination with carbonic and
sulphuric acids. The carbonate of strontia or strontianite,
effervesces with acids, and burns with a purple flame. It contains
about 60 or 70 per cent. of earth. The sulphate of strontia, or
celestine, contains about 57 of strontia.

When carbonate of strontia is mixed with charcoal powder, and exposed
to a heat of 140° of Wedgwood's pyrometer, the carbonic acid will
be expelled, and pure strontia remain. The earth may be obtained
in a pure state, by dissolving the carbonate in nitric acid, and
evaporating the solution until it crystallizes, and exposing the
crystals, in a crucible, to a red heat, until the nitric acid is
driven off. If the carbonate cannot be had, the sulphate may be
employed. For this purpose, it is to be pulverized and mixed with
an equal weight of carbonate of potassa, and boiled in water. The
carbonate of strontia, thus obtained, which exists in the form of a
powder, is to be treated with nitric acid as already described.

Strontia, like the other earths, is a compound body, having a
metallic basis, called _strontium_, which, united with oxygen, forms
the earth.

The specific gravity of strontia approaches that of barytes. Like
pure barytes, it is soluble in water, forming strontia water. It
requires rather more than 160 parts of water at 60° to dissolve it;
but much less of boiling water.

The solution of strontia in water, when evaporated, will crystallize
in thin, transparent, quadrangular plates, generally parallelograms,
seldom exceeding a quarter of an inch in length. These crystals
contain about 68 per cent. of water; and are soluble in little
more than twice their weight of boiling water, and in 54.4 times
their weight of water at 60°. When dissolved in alcohol, they give
a blood-red colour to its flame. The solution of strontia changes
vegetable blues to green. Strontia differs from barytes in being
infusible, much less soluble, of a different form, weaker in its
affinities, and not poisonous.

The metallic base of strontia, which was discovered by Sir H. Davy,
in 1808, when exposed to the air, or when thrown into water, rapidly
absorbs oxygen, and is converted into strontia.

As strontia communicates a red colour to flame, it has been used in
certain compositions of artificial fire. The brilliant red fire,
sometimes used in theatres, owes its colour to this earth. See
_Theatrical fire-works_. Muriate and nitrate of strontia will give a
red or purple colour to the flame of alcohol. See _coloured flame of
alcohol_.

If a piece of cloth be dipped in a solution of muriate, nitrate,
or acetate of strontia, or in strontia water, and then immersed in
alcohol, it will burn with a red flame.

M. Fourcroy, (_Système des Connaissances Chimiques, &c._ tome iii,)
mentions the use of nitrate and muriate of strontia, in artificial
fire-works, for the purpose of communicating a red colour to the
flame of combustible bodies. Since that time, the nitrate, in
particular, has been recommended and used.

One of the characters of the salts of strontia, is, that they give a
red flame to burning bodies; whereas the salts of barytes or of lime,
used in the same manner, communicate a yellow flame.

The saline combinations of strontia were examined with particular
attention by Dr. Hope. See _Edinburg Philosoph. Transactions_ for
1790.

Nitrate of strontia may be formed by dissolving carbonate of
strontia, or the sulphuret obtained by decomposing the sulphate by
charcoal, in nitric acid, filtering the solution, evaporating it, and
suffering it to crystallize.

Nitrate of strontia deflagrates on ignited coals. Dr. Hope pointed
out, that if nitrate of strontia be exposed to a red heat, and a
combustible substance be, at this time, brought in contact with
it, a deflagration, with a very vivid red flame, will be produced.
When a crystal of this salt is put into the wick of a candle, it
communicates a beautiful purple flame. It does not deliquesce in the
air, and, therefore, the compositions, into which it enters, cannot
spoil on that account. Nicholson (_Chemical Dictionary_,) observes,
that nitrate of strontia may be used in the art of pyrotechny.
For this purpose, however, it is mixed with sulphur, chlorate of
potassa, and sulphuret of antimony; and sometimes with the addition
of sulphuret of arsenic and charcoal, as in the _red fire_ for
theatrical uses.

The muriate of strontia has similar properties. Davy first observed,
that when strontia was heated in chlorine gas, it gave out oxygen
gas, and a chloride of strontium was formed.

Muriate of strontia is formed very readily, by dissolving the
carbonate or sulphuret of strontia in muriatic acid, and evaporating
the solution in order to obtain crystals. These crystals are very
soluble in water. They are soluble, also, in twenty-four times their
weight of pure alcohol, at the temperature of 60°. This alcoholic
solution, we remarked, burns with a fine purple colour. These
crystals suffer no change when exposed to the air, except they be
very moist; in which case, they deliquesce. When heated, they first
undergo the watery fusion, and are then reduced to a white powder.
Fourcroy recommends the muriate of strontia for fire-works.

Carbonate of strontia, when thrown in powder on burning coals,
produces red sparks.

Acetate of strontia, another salt used in fire-works, is formed
by dissolving strontia, or its carbonate, in acetic acid. It will
crystallize. The crystals are not affected by exposure to the air.
When heated, its acid is decomposed, as happens to all the other
acetates.

_Sec. LIX. Of Boracic Acid._

Borate of soda, or borax, is a salt, which has long been known, and
is used chiefly in the arts as a flux for the fusion of bodies, and
for soldering. Boracic acid is a compound body, consisting of a newly
discovered substance, called boron, and oxygen. Homberg obtained
the acid from borax in 1702, by distilling a mixture of borax, and
sulphate of iron. He supposed that it was a product of the latter;
and hence it was called the _volatile narcotic salt of vitriol_, or
_sedative salt_.

Boracic acid forms two salts with soda; the borate, properly so
called, and borax. It is supposed to be our borax, that Pliny
mentions under the name _crysocolla_, so called by the ancients.
Others, however, assert, that their crysocolla was nothing more than
the rust of copper, triturated with urine. The impure borax in the
East Indies, is called _tincal_. When borax is melted, and exposed
for some time to heat, it loses its water, and is changed into what
is known by the name of _calcined borax_.

The easiest process for obtaining boracic acid is to make a
concentrated solution of borax in hot water, and add by degrees,
sulphuric acid, which will unite with the soda; and, as the fluid
cools, the boracic acid will separate in shining laminated crystals.
No more acid should be added than is sufficient to make the solution
slightly sour. The crystals are to be washed with cold water, and
drained upon brown paper.

One of the principal characters of boracic acid is, that it is very
soluble in alcohol, to the flame of which it communicates a green
colour. Paper dipped in this solution, burns in the same manner.

In consequence of this property of imparting a green colour to
flame, I made some experiments with it, for the purpose of preparing
_green fire_; and found, that, by employing it in the proportion of
one-eighth, the flame was always green, provided that the flame of
the combustible used, was not tinged of any other colour. Nitre,
charcoal, and boracic acid will give a green; also nitre, lamp oil,
and boracic acid; nitre, alcohol, and boracic acid, along with
charcoal; and chlorate of potassa, charcoal, and boracic acid, with
or without the addition of alcohol. But, although boracic acid
communicates a lively green, its expense will prevent its use in that
way, especially as many other preparations, as those of copper, will
have the same effect, and are more economical on account of their
price. See the _Coloured Flame of Alcohol, and Coloured Fire_.

Oils, when assisted by heat, will dissolve boracic acid. In naphtha,
it is very soluble. With oils, it yields fluid and solid products,
which give a green colour to the flame of alcohol. It is not a
combustible acid, but only imparts colour to the flame of combustible
bodies.

Boron will unite with fluorine, the radical of fluoric acid. When
one part of vitrified boracic acid, two of fluate of lime or fluor
spar, and twelve of sulphuric acid are distilled, an acid gas will be
obtained, called fluo-boric gas. For the properties of boron, consult
Thenard's _Traité de Chimie_.

PART II.

INSTRUMENTS, TOOLS, AND UTENSILS.

CHAPTER I.

OF THE LABORATORY.

The laboratory for pyrotechny may consist of a building, furnished
with furnaces, boilers, &c. for the preparation or refining of
saltpetre, and other substances for use; but according to its
present acceptation, it is a place where all kinds of fire-works
are prepared, both for actual service and for exhibition; such as,
besides the ordinary works for show, quick matches, fuses, port-fire,
grape-shot, case-shot, carcasses, hand granades, cartridges, &c. It
should have tables, benches, and closets, where the tools, paper,
thread, &c. may be commodiously placed, and an adjoining room to
contain a supply of materials for two days' work.

The chief artificer takes the weight of the materials made use of,
attends to the weighing of the different substances, and sees that
the mixtures are made properly, &c. He also keeps an account of the
number and kinds of fire-works. The prepared fire-works ought to be
removed daily to the magazine. If they are made up in the field,
under a tent, (denominated the _Laboratory tent_,) they should be
packed in barrels or in caissons.

_Sec. I. Of Laboratory Tools and Utensils._

The following constitute the furniture and equipments of a laboratory:

Copper rods, to load port fires, and the fuses of shells,
howitzers, &c.
Wooden formers, on which to roll the paper cases of the port
fires.
Wooden formers, to roll the cases of rockets.
Balances, large and small, with weights, &c.
Buckets to carry water.
Boxes for loading priming tubes.
Barrels with leather tops, that draw, in order to keep grained
and meal gunpowder.
Rods, or rammers for charging rockets.
Brushes to wipe the tables and sweep the compositions together.
Frames to dry priming tubes.
Copper calibers to regulate the size of priming tubes.
Penknives.
Needles for piercing priming tubes in the direction of their
length.
Fuse drivers.
Coopers' adzes.
A copper kettle.
Scissors for cloth and paper.
Paper cutters.
Priming wires.
Skimmers for skimming the froth of boiling saltpetre.
Funnels for charging port-fires, howitzers, shells, &c.
Square ruler.
Fuses for shells, &c. (or a lathe to make them.)
Large and small wooden bowls.
Small axes.
Ladles for charging the fuses of shells, port-fires, &c.
Mallets to hammer the fuses.
Glue pots and brushes.
Heavy mallets to beat the powder.
Tin measures, of different sizes.
Hand mortar.
Foot rules.
Rat-tail files to cleanse the interior of the reeds of priming
tubes.
Wooden rasps.
Iron rulers, 1/2 foot long.
Leather bags, in which gunpowder and charcoal are reduced
to powder.
Pocket saws.
Pallet knives for saltpetre.
Tables, small ones to mix the composition; large ones with
a ledge to meal the powder on.
Sieves, fine and common; of silk, and of hair.
Fuse drawers.
Tools for rolling cartridges.
Gimblets of different sizes.

The materials required more particularly for military fire-works, are:

Gunpowder.
Saltpetre.
Sulphur.
Charcoal.
Camphor.
Beeswax.
Glue, rosin.
Cotton yarn for quick match.
Brandy or other spirits.
Gum arabic.
Linseed oil.
Spirits of turpentine.
Pitch.
Reeds or quills for priming fuses.
Mutton tallow.
Vinegar.
Thread for tying quick match.
Cartridge paper.
Thread, tow and spun yarn, to make match rope.
Cordage, to make tourteaux.
Flour to make paste.

The characters used to express certain substances employed in
fire-works, are the following: (_James's Mil. Dict._ p. 101.)

M. means meal powder,
⊝. Saltpetre.
C. Z. Crude sulphur.
C. S. Sea coal.
S. x Steel or iron filings.
G. x Glass dust.
C. I. Cast iron.
X. Camphor.
B. L. Lampblack.
L. S. Lapis Calaminaris.
W. Spirits of wine.
P. O. Oil of spike.
∋. Corn powder.
Z. Brimstone.
C. + Charcoal.
B. R. Beech raspings.
B. x Brass dust.
T. x Tanners' dust.
C. A. Crude antimony.
A. Y. Yellow amber.
G. I. Isinglass.
⩀. Gum.
S. T. Spirits of turpentine.

_Sec. II. Of Mandrils and Cylinders for forming Cartridges and Cases._

The rollers or rods, on which cartridges are formed, ought to be
solid, and perfectly straight and round. Very dry, sound wood
should be selected, and when turned, the rod should be perfectly
cylindrical; one extremity being concave, and the other convex.

Mandrils may be made of copper, which is preferable to wood, as this
is apt to warp and crack; and in both cases, should be longer than
the cartridge, so as to be drawn out easily. They are of different
lengths and diameters, according to their respective uses.

_Sec. III. Of Rammers, Chargers, and Mallets._

The rammers which are used for compression, are cylindrical like
the preceding. They have a head much larger in dimensions than the
part that enters the tube. (See A, B, C, D, and E of Fig. 1. in the
Plate). Besides being made of wood, which should be of the hardest
kind, as _lignum vitæ_, they may be formed of copper or brass. In
this case, they are first cast of the requisite size and shape, and
finished in a lathe. Wooden heads are sometimes put to them, but with
little advantage; as they frequently split and require to be renewed.

The wooden rammer may be struck with metal; but when the rammer is of
copper or brass, wooden mallets must be always employed.

We may here remark, that in charging rockets, it has been customary
to employ several rammers. The first _drift_ must be six diameters
from the handle, and this, as well as all other rammers, ought to
be a little thinner than the former, to prevent the tearing of the
paper, when the charge is driven in. In the end of this rammer is a
hole to fit over the piercer. (See B. Fig. 1.) The line marked on
this rammer, as will be explained hereafter, when it appears at the
top of the case, indicates that a second rammer must be used. This
second rammer, from the handle, is four diameters, having a hole for
the piercer, 1-1/2 diameters long. (C. Fig. 1.) When the case is
filled as high as the top of the piercer, a short and solid drift is
used. (E. Fig. 1.).

Rammers must have a ferrule, or collar of brass at the bottom, to
keep the wood from spreading, or splitting. With regard to the
handles of the rammers, if their diameter be equal to the bore of
the mould, and two diameters long, the proportion is a good one. The
shorter they can be used, the better. The longer the drift, the less
of course, will be the pressure on the composition, by the blow given
by the mallet.

We may observe here, that rockets may either be driven over a
piercer, or driven solid, and afterwards bored.

As much of the effect of rockets depends upon the manner they are
driven, whether lightly or compactly, or uniformly throughout,
circumstances which affect their quality; it is necessary, in using
the rammer, to employ an equal force for driving the composition.
The mallet, therefore, should be of a given weight; and a certain
number of strokes with the same force, on each new charge, must be
accurately followed, until the driving is completed; taking care, at
the same time, that the rocket stands firm on a solid body.

Dry beech is the best wood for mallets. A writer very judiciously
observes, in the _Encyclopedia Britannica_, (vol. xv, 695), that,
if a person uses a mallet of a moderate size, in proportion to the
rocket, according to his judgment, and if the rocket succeeds, he
may depend on the rest, by _using the same mallet_; yet it will be
necessary, that cases of different sorts, be driven with mallets of
different sizes. In all cases, under one ounce, the charge may be
rammed with an ounce mallet.

There is an advantage, also, by having the handle of the mallet
turned out of the same piece as the head, and made in a cylindrical
form. If their dimensions are regulated by the diameters of the
rockets; then, for example, if the thickness of the head be three
diameters, and its length four, the length of the handle will be five
diameters, whose thickness must be in proportion to the hand.

Bigot (_Artifice de Guerre_, p. 118) speaking of the flying fuses,
or sky-rockets, observes, that the mallet used for driving the
composition, is proportionably large, according to the rockets, and
that it is five inches in length, and four in breadth, when the
diameter of the rocket is from 12 to 18 lines. The mallets for larger
rockets are stronger and heavier, and, in some instances, where a
great force is required, as in driving war-rockets, a machine similar
to the pile-engine, is used. See _Congreve Rockets_.

_Sec. IV. Of Utensils necessary for constructing of Signal Rockets._

A detailed account of the tools used in making signal rockets, may be
seen in Ruggeri, _Pyrotechny_, p. 143; but M. Bigot has enumerated
them as follows:

One mandril for forming the cartridge, or case.
One pair of curved compasses to determine the exterior
diameter.
Three conical mandrils. (See fig. 3, plate.)
One solid, or massive cylinder.
One mould for garnishing.
Two moulds for the capitals, or heads, one of which is for
the rockets with, and the other for the rockets without,
the _garnish_, or furniture.
One piercer and block (See plate, fig. 1, I & H.)
One scoop.
One punch.
One mallet.
One press.
One large knife.
One pair of scissors.

All the wooden utensils ought to be made of hard and sound wood,
without knots. The rammers should be furnished with rings or
ferrules, and the first bored with a hole of sufficient length
to receive the piercer. The second should be bored deep enough
to receive two-thirds of the piercer, and the third, to receive
one-third, while the fourth should be solid. These rammers are all
furnished with heads. (See section iii.)

_Sec. V. Of the Rolling, or Plane Board._

This board is furnished with a handle, and is used for rolling
rocket cases, &c. and is of different dimensions, according to its
application. It is made of hard wood, such as oak or walnut.

When the paper is wrapped round the mandril or _former_, the rolling
board is used to compress the paper, and make it round and smooth.

_Sec. VI. Of the Driver for charging large Rockets._

This contrivance is similar to a pile driver in construction; and, by
means of a weight falling upon the rammer, the charge is sent home
with great force. Its use is confined to the largest kind of rockets.

_Sec. VII. Of Mortars and Pestles._

Mortars are employed for the pulverization of substances, and,
according to their use, may be either of wood, marble, brass, or
cast-iron, which last costs less than the others. Large mortars have
covers, in order to confine the finer particles. The pestles should
be of very hard wood; because, in that case, no danger would be
apprehended of an explosion of the materials, an occurrence which
might take place, if iron were used. This, however, depends on the
substances submitted to the pestle.

_Sec. VIII. Of the Choaker or Strangler._

The choaker is nothing more than a contrivance, usually made of
rope, by which the closing of the end of the rocket is effected, so
as to form a kind of cup or mouth.

_Sec. IX. Of the Table and Sack for mealing Gunpowder._

This table may be either square or an octagon, and made of hard wood.
There is a rim, a few inches high, raised round it, and a gutter
at one end to allow the powder to pass out, when the operation is
finished. See plate, fig. 7 and 8.

This mode of mealing powder is by no means to be preferred. (See
_Gunpowder_.)

A sack is also used for crushing powder. It should be made of strong
elastic leather, and sewed together in such a manner as to prevent
the impalpable powder from passing through its seams. They are of
an oblong shape, and contain from 20 to 25 pounds. Fifteen pounds
are generally put in at a time. This method of crushing powder is
preferred, as it is less liable to accidents. It is hardly necessary
to add, that the bag is beaten with a cylindrical stick.

_Sec. X. Of Sieves._

There are several kinds of sieve. The common sieve has neither a
cover nor a receiver, and may be either formed of horse hair, or of
brass or copper wire. It is necessary to have some sieves of a finer
kind. For this purpose, silk and gauze are generally used. The cover
is merely leather, fixed in a frame, which fits on the top. The
receiver is formed nearly in the same manner, having a skin stretched
over a frame, which fits on the under part of the sieve.

_Sec. XI. Of the Paper Press._

A press, for the purpose of pressing paper, is formed of two pieces
of wood, which are brought together by means of one, or several
screws. This press is sometimes, though seldom, used. If pasteboard
is made, when it cannot be had ready prepared, then the press is
actually necessary. The intention is to unite the several sheets,
which have been pasted, by using the pressure of the screw, and
to remove any extraneous paste, so that the paper may have no
inequalities on its surface. In lieu of the screw-press, heavy
weights laid on the paper for several hours, will answer the same
purpose.

CHAPTER II.

_Preliminary operations in the preparation of fire-works, and
observations on the preservation of gunpowder, and sundry
manipulations._

_Sec. I. Of the Workshop._

We have already noticed the principal furniture of a laboratory, and,
therefore, can add nothing new on this head. There are, however, some
utensils employed for particular works, which we may here describe.

In the disposition of the workshop, the tables, utensils, &c. are
arranged, according as the judgment may dictate for convenience
and use. Care must be taken to prevent the access of fire, and to
prevent, as far as possible, the presence of moisture. Lanterns, if
light is required, are always to be preferred; but the best manner of
communicating light is through a window, placing the lights outside
of the building, or apartment, as is done in powder mills. Other
precautions may be necessary, which will readily suggest themselves.

In conducting the work, the workmen are to be so arranged, as that,
while some are employed in the preliminary operations, others are
making and finishing the preparations. The compositions may be ready
prepared, and well preserved in jars or other vessels. This is named
by the French, _Cabinet de composition_. It is a place, also, where
the substances are weighed, and mixed.

_Sec. II. Of the Magazine._

The magazine is a place of deposite for gunpowder, to preserve it
from fire, and moisture. We have already mentioned the preservation
of gunpowder in the article on that subject; but it may not be
improper to offer some remarks, respecting the construction of
magazines.

Authors differ in opinion, both in regard to their situation and
construction; but they all agree, that they ought to be arched,
and bomb-proof. The first powder magazines were made with gothic
arches: Vauban constructed them in a semicircular form, to make
them stronger. Their dimensions were, sixty feet long, within, and
twenty-five broad. The foundations were eight or nine feet thick, and
eight feet high, to the spring of the arch. The floors were two feet
from the ground, for the purpose of keeping the magazine free from
dampness.

It is observed, that the centres of semicircular arches will settle
at the crown, and their sinking must break the cement. A remedy was
applied for this inconvenience, by the _arch of equilibration_, as
described in Hutton's work on bridges. As, in powder magazines,
the ill effect of the breaking of the cement is particularly felt,
Mr. Hutton proposed to find an arch of equilibration for them in
particular, and to construct it, when the span is twenty feet,
the pitch or height, ten, (which are the same dimensions as the
semicircle), the inclined exterior walls at top, forming an angle of
113 degrees, and the height of their angular point, above the top of
the arch, equal to seven feet.

A wall built round a magazine, gives it an additional security. The
roof should be slated, or covered with lead or copper, and it ought
to be furnished with a lightning rod, placed ten or fifteen yards
from the building. The points of the rods may be either gilt, or
of solid gold. Silver, however, is generally used; but, above all,
platinum is to be preferred. The advantage of these points is, that
they do not rust like iron, or become oxidized, an occurrence which
would diminish their powers as conductors of the electric fluid.

To prevent the access of moisture, or rather to absorb it, some have
recommended the inner walls to be covered with a composition of
powdered coal, &c. Lining of magazines with sheet lead, appears to
have some advantages.

St. Pierre observes, that a Prussian officer informed him, that,
having remarked that vapour was attracted by lead, he had employed
it for drying the atmosphere of a powder magazine, constructed
under ground, in the throat of a bastion, rendered useless from its
humidity. He ordered the concave ceiling of the arch to be lined with
lead, where the gunpowder was deposited in barrels: the vapour of the
wall collected in drops on the leaden roof, ran off, and left the
gunpowder barrels perfectly dry.

_Sec. III. Of the Driving or Ramming of Sky-rockets._

We purpose in the present article to give some general directions for
the driving of rockets.

Rockets may be driven solid, or over a piercer. In the latter case,
they must not have so much composition put in them at a time. The
piercer, accompanying a greater part of the bore of the case, would
cause the rammer to rise too high; so that the pressure of it would
not be so great on the composition, nor would it be driven equally.
For rockets rammed over a piercer, let the ladle, or copper scoop,
hold as much composition, as, when driven, will raise the drift
one-half the interior diameter of the case; and, for those driven
solid, let it contain as much as will raise the drift one-half the
exterior diameter of the case. Ladles are generally made to go easily
into the case, and the length of the scoop is about one and a half of
its own diameter.

The charge of rockets must always be driven one diameter above the
piercer, and, on it, must be rammed, one-third of a diameter of
clay; through the middle of which a small hole must be bored to the
composition, so that, when the charge is burnt to the top, it may
communicate its fire, through the hole, to the stars in the head.
(See plate, fig. 14.) Great care must be taken to strike, with the
mallet, with an equal force, giving the same number of strokes to
each ladleful of composition; otherwise the rocket will not rise with
a uniform motion, or burn equally and regularly, for which reason,
they cannot carry a proper tail. It will break, in this case, before
the rocket has ascended to its extreme height, where the rocket
should break and disperse the stars, rain, or whatever is contained
in the head. When in the act of ramming, the drift or driver must
be kept constantly turning or moving; and when the hollow rammers
are used, the composition is to be knocked out every now and then,
or the piercer will split them. To a rocket of four ounces, give to
each ladleful of charge, 16 strokes; to a rocket of 1 lb. 28; to a
2 pounder, 36; to a 4 pounder, 42; to a 6 pounder, 56. But rockets
of a larger sort cannot be driven by hand, and must be rammed with a
machine similar to a pile-driver.

The method of ramming wheel cases, or any other sort, in which
the charge is driven solid, is much the same as that used for
sky-rockets; for the same proportion may be observed in the ladle,
and the same number of strokes given, according to their diameters,
all cases being distinguished by their diameters. In this manner,
a case, whose bore is equal to that of a rocket of four ounces, is
called a four ounce case; and one which is equal, in bore, to an
eight ounce rocket, an eight ounce case, &c. The method of ramming
cases, without moulds, will answer for strong pasted cases, and save
the expense of making so many moulds. In filling any case, it must be
placed on a perpendicular block of wood, in order to keep it firm and
solid; otherwise the composition would be rammed unequally.

When cases are to be filled without moulds, procure some nipples,
made of brass or iron, in proportion to the cases, to screw or fix
in the top of the driving block. When the nipple is fixed in, make,
at about one and half inches from it, a square hole in the block,
six inches deep, and one inch in diameter. Then have a piece of
wood, six inches longer than the case intended to be filled, and two
inches square. On one side of it, cut a groove, almost the length
of the case, whose breadth and depth must be sufficient to cover
near one-half the case. Then cut the other end, to fit the hole in
the block; but take care to cut it, so that the groove may be at a
proper distance from the nipple. This half mould being made, and
fixed tight in the block, cut, in another piece of wood, nearly of
the same length as the case, a groove of the same dimensions as that
in the fixed piece. Then put the case on the nipple, and, with the
cord, tie it, and the two half moulds together; and the case will be
prepared for filling. The dimensions of the above half moulds are
proportionable for cases of eight ounces; but they differ in size in
proportion to the cases.

_Sec. IV. Of the Boring of Rockets._

The machine, for boring rockets, is similar, in some respects, to a
lathe. The rocket is confined in a box, and, by means of a wheel,
which is made to turn a second one, an auger rammer is put in motion.
The rammer must be of a size, proportionate to the rocket, and of
the same diameter, as the top of the bore intended, and continue of
that thickness, a little longer than the depth of the bore required.
The thick end of each _rammer_ must be made square, and all of the
same size. The rammer is made to move backward, and forward, so that,
after the rammer is marked three and a half diameters of the rocket,
from the point, set the guide, allowing for the thickness of the
front of the rocket box, and the neck and mouth of the rocket. When
the rocket is fixed in the box, it must be pushed forward against the
rammer, and, when the scoop of the rammer is full, draw the box back,
and knock out the composition. A little oil is sometimes used, to
prevent the friction from setting fire to the rocket. Having bored a
number of rockets, taps must be used. These taps are similar to the
common spicket. When employed, it is necessary to mark them three and
a half diameters from the point, allowing for the thickness of the
rocket's neck.

There are several contrivances for the boring of rockets. The
operation is sometimes done, by confining the rocket in a box, and
boring it with a borer, fixed in a brace, using, at the same time,
a proper director. This brace is like the common _brace_, used by
carpenters, or formed on that principle, and made of iron. The
motion, given by the hand, performs the operation.

_Sec. V. Of the Preservation of Steel or Iron Filings._

When treating of iron, we mentioned, that it has the property of
oxidizing rapidly, when exposed to the air and moisture; and that its
effects in fire-works, in that case, would be either destroyed, or
considerably diminished. And even fire-works, in which iron enters as
a component part, will, if kept long, lose some of their effect, in
consequence of the change, which the iron suffers; for, instead of
producing brilliant sparks, which is their intention, it would impart
a dull red appearance.

Two methods are recommended for the preservation of iron. The one
is to melt a portion of sulphur, and throw the filings into it, and
afterwards to separate the extraneous sulphur. The other consists
in wrapping them up in oiled paper. As to the first method, we may
apprehend the effect of the sulphur, combining with some of the iron,
instead of coating it, forming thereby a sulphuret, which, besides,
is readily decomposed by the contact of air and moisture, producing
sulphate of iron. The second method, of wrapping them in oil, or, in
fact, covering them with oil, is certainly a greater preventive from
rust, for where the oil is in contact, no oxidizement can take place.

There are several methods recommended to preserve iron-work from
rusting. The use of paint and varnish for this purpose is familiar.
In Sweden, they cover iron-work with a mixture of pitch, tar, and
wood soot, which acquires a gloss, similar to that of varnish, and
is said to prevent the oxidizement of the metal very effectually.
Fat-oil varnish, mixed with four-fifths of rectified spirit of
turpentine, has been recommended. It is applied with a brush, or
sponge. Articles, varnished with this preparation, are said to retain
their metallic brilliancy, and never contract any spots of rust.
Another composition, for the same purpose, is highly recommended. It
consists in applying a mixture of one pound of hogs' lard, free from
salt, one ounce of camphor, two drachms of black lead in powder, and
two drachms of dragon's blood. At Sheffield and Birmingham, sundry
articles, made of steel and iron, are preserved from rust, when sent
to foreign markets, by wrapping them in coarse brown paper, prepared
first with oil.

Among the different preparations, recommended at various times to
prevent iron from contracting rust, we may mention one, which has
been used with success, and which gives a lead colour. It is nothing
more than taking some litharge, and heating it in an iron pot, and
scattering over it some sulphur. The litharge will change its colour,
forming a kind of sulphuret of lead, which is then ground with drying
oil, and applied like paint. We are told, that this preparation gets
remarkably hard, and resists the weather more effectually than any
other lead colour.

_Sec. VI. Of the making of Wheels and other Works incombustible._

It is usual to give a coat of paint to the wood-work of wheels, &c.
which are designed to carry a number of cases. To prevent their
taking fire, paint, in some measure, has the effect. The following
composition is recommended: Take brick dust, coal-ashes, and iron
filings, of each an equal quantity, and mix them with a double size,
made hot. Apply this to the wood, and when dry, give it another coat.

Several methods have been adopted for the same purpose; but wood
may be made to resist, in a great degree, the action of fire, and
rendered almost incombustible, by soaking it in a solution of the
supersulphate of potassa and alumina, (alum), in sulphate of iron,
(green vitriol), and in other salts, which are incombustible.

With respect to the use of alum as a preservative against fire, it
is certain, that, although its use in this way is very ancient, it
was not often recommended; for writers on the art of war, such, for
example, as Anas, mentions the use of vinegar, in the following
quotation from his _Poliorcet._ cap. 24: "Majus juverit, si prius
ligna aceto linantur; nam a materia aceto illita, ignis abstinet."

The use of alum, to prevent substances from taking fire, is not a new
invention; notwithstanding we find it recommended in modern works,
not only for wood, but also for paper, and linen and cotton dresses,
&c. Aulus Gellius relates, that Archelaus, one of the generals of
Mithridates, washed over a wooden tower with a solution of alum, and
thereby rendered it so much proof against fire, that all Sylla's
attempts to set it in flames proved abortive.

A writer in the _Anthologia Hibernica_, vol. iii, for 1794,
observes, that the use of alum to prevent the action of fire, on
wood, or other combustible bodies, is not new, and those, who lay
claim, are not entitled to originality on that head.

Another mode to prevent wood from taking fire may also be adopted. It
consists in mixing together, one ounce of sulphur, one ounce of red
ochre, and six ounces of green vitriol. The wood work is covered with
joiners' glue, and the mixture is then put over it. This process is
to be repeated three or four times, allowing the glue to dry before a
new coat is applied.

There are several other preparations for the same purpose, not only
for the covering of wood, but also paper. But M. Ruggeri is of
opinion, that they cannot be depended upon, when used on paper; for
the paper will, in part, be consumed. The formula for one of these
compositions, is thus given by that gentleman: To a pound of flour,
mix a handful of powdered alum, and add to it strong glue-water, and
bring it to a proper consistence with clay. Flour and glue-water,
mixed together, with the addition of a small quantity of muriate
of soda, (common salt), is also recommended for the same purpose.
Wood, steeped in a solution of common salt, so as to be thoroughly
impregnated with it, is very difficult of combustion. In Persia, salt
is used to prevent timber from the attack of worms. The practice of
_salting_ ship timber is highly recommended.

Wood, in fact, may be rendered incombustible by several processes,
some of which we have given. Earl Stanhope, among others, made some
interesting experiments on this subject.[23]

Having thus given some of the modes, usually adopted to render wood
incombustible, or to prevent its taking fire so instantaneously, we
purpose to add some remarks respecting the processes for colouring
it. An excellent preservation against moisture, which communicates
a colour at the same time, is formed of 12 lbs of rosin, 3 lbs
of sulphur, and 12 pints of whale oil, melted and mixed with a
sufficient quantity of red or yellow ochre, and applied by means of
a brush. Pulverized black lead may be substituted for the ochre.
Several coats of this mixture may be put on, allowing each coat to
dry before another is applied. This composition is particularly well
adapted for wheel work, &c. and for aquatic fire-works. Chaptal
advises, for the same purpose, a mixture of equal parts of white
turpentine, bees' wax, and maltha, or, in the place of maltha, coal
tar. Wood, covered with three coats of this composition, and immersed
for two years in water, was found to be quite dry. It would be well,
however, to cover it with some of the preparation, to render wood
incombustible.

With respect to the staining of wood of various colours, several
preparations may be used. To communicate a green colour, a hot
solution of acetate of copper may be used; or verdigris, alum, and
vinegar, boiled together. A decoction of brazil wood, with alum and
cream of tartar, will impart a red; indigo, dissolved in sulphuric
acid, (liquid blue dye), a blue; a decoction of logwood, nut-galls,
and copperas, a black; a solution of dragon's blood, or of alkanet
wood, in turpentine, a mahogany colour, &c. The imitation of bronze
on wood may be effected, by covering it first with isinglass size,
then suffering it to dry, and putting on a coat of oil gold size, and
covering it with bronze powder, a preparation sold for that purpose.
A solution of aloes in spirits, which communicates a greenish-black,
is a great preservative of wood against worms.

M. Ollivier (_Archives des Découvertes_, v, p. 386) has given a
variety of recipes for imitating bronze, stone, &c. He recommends the
following for the imitation of ancient bronze, which may be applied
to wood-work. Melt together 150 lbs of fine sand, 170 lbs of lead
ore, (Galena), and 30 lbs of manganese, and add one-sixth part of
brass. This compound is then pulverized. It is applied on the usual
ground.

_Black earth_, as it is called, made of green earth, oxide of
manganese, oxide of iron, and oxide of copper, is also recommended
for covering wood-work. The composition for _imitation marble_, is 1
part of green earth, 1/2 a part of sand, and 1/8th of a part of bol.
armen. By adding 1/14th part of _yellow burnt copper_, the colour
will approach to green. The same composition, with 1/16th part of
copper, and 1/32d iron, will give a black.

_Sec. VII. Of the formation of Rocket, and other Cases._

The cases for rockets, as a general rule, are to be made 6-1/2 times
their exterior diameter in length; and all other cases, that are to
be filled in moulds, must be as long as the moulds, within a half of
the interior diameter. Rocket cases, from the smallest, to 4 or 6
pounds, are generally made of the strongest sort of cartridge paper,
and rolled dry; but the large sort are made of pasted pasteboard.
(See observations on that subject.) As it is very difficult to roll
the ends of the cases quite even, the best way is to keep a pattern
of the paper for the different kinds of cases. These patterns should
be longer than the case they are designed for, and the number of
sheets required should be marked, which will prevent any paper being
cut to waste. Cut the paper of a proper size, and the last sheet
for each case, with a slope at one end; so that when the cases are
rolled, it may form a spiral line round the outside; and that this
slope may always be the same, let the pattern be so formed for a
constant guide. Before you begin to roll, fold down one end of the
first sheet so far, as that the fold will go two or three times round
the former; then, in the double edge, lay the former with its handle
off the table, and after rolling two or three turns, lay the next
sheet on that which is loose, and roll it all on.

The smoothing board, which is about twenty inches long, is now to
be applied; and after rolling the paper three or four times, lay
on, in the same manner, another sheet of paper, and smooth it in
the same manner. This operation is to be repeated till the case is
sufficiently thick. When the last sheet is rolled, we must observe,
that the point of the slope is placed at the small end of the roller.

The case being made, the small end of the former is put in, to about
one diameter of the end of the case, and the end piece is inserted
within a little distance of the former. Then give the pinching cord
one turn round the case, between the former and the end piece. At
first, pull easy, and keep moving the case, which will make the neck
smooth, and without large wrinkles. This operation is called by the
French _strangling_, or _choaking_. When the cases are hard to choak,
let each sheet of paper (except the first and last in that part where
the neck is formed) be a little moistened with water. Immediately
after you have struck the concave stroke, bind the neck of the case
round with small twine, which must not be tied in a knot, but
fastened with two or three hitches.

Having thus pinched and tied the case, so as not to give way, put
it into the mould without its foot, and, with a small mallet, drive
the former hard on the end piece, which will force the neck close
and smooth. When this is done, cut the case to its proper length,
allowing, from the neck to the edge of the mouth, half a diameter,
which is equal to the height of the nipple. Then take out the former,
and drive the case over the piercer with the long rammer, and the
vent will be of a proper size.

Wheel cases are sometimes driven on a nipple, with a point to close
the neck, and make the vent of the size required; which, in most
cases, is generally 1/4th of their interior diameter. As it is very
often difficult, when the cases are rolled, to draw the roller out, a
hole must be made in its handle, and a pin, as a purchase, put in.

The machine for pinching cases consists of a treadle, which, when
pressed hard with the foot, will act upon a cord, and draw it tight.
The cord runs over a small pulley, and is fixed to an upright piece.
It is wound once round the case, between the former and end piece;
and when the cord is drawn, the case is brought together.

Cases are commonly rolled wet for wheels and fixed pieces; and when
they are required to contain a great length of charge, the method of
making these cases is thus: The paper must be cut as usual, except
the last, which ought not to have a slope. Having it ready, paste
each sheet on one side, and then fold down the first sheet as before
directed; but be careful that the paste does not touch the upper
side of the fold. If the roller be wetted, it will tear the paper
in drawing it out. In pasting the last sheet, observe not to wet
the last turn or two in that part where it is to be pinched; for if
that part be damp, the pinching cord will stick to it, and tear the
paper. Therefore, in choaking those cases, roll a bit of dry paper
once round the case, before the pinching cord is used. This paper
is to be taken off after the operation. The rolling board, and all
other methods, according to the former directions for the rolling and
pinching of cases, must be used for these, as well as other cases.
See _Encyclopedia Britannica_, vol. xv, p. 692.

Morel, in a practical work, (_Traité Practique des Feux d'Artifice_)
speaking of rocket cases, observes, that the rule is, to give to
their thickness, half the interior diameter, or half the diameter of
the roller. If the roller, for instance, were half an inch, the case
should be 1/4th of an inch in thickness. A rocket is divided into
three equal parts; two for the interior diameter, and one for the
thickness of the case.

As to the length of sky-rockets, it is regulated by the length of the
piercer, if they are pierced in the charging. One-third more than
this length is allowed for the _choak_, and the rest, of course, for
the composition. With respect to other cases, Morel remarks, that the
cases for turning pieces are usually six inches in length, and, for
fixed pieces, seven and eight inches. The cases of _Roman candles_,
are of the same thickness as those of rockets. In length they are, as
well as the _Mosaic candle_, fifteen inches. They are choaked and cut.

Those of _serpents_ are made with one or two cards, which are rolled
upon a former of wood, or metal, 1/4th of an inch in diameter, and
four inches in length. When made, the case measures three inches. Dry
rolling is considered sufficient for these cases.

The _fixed stars_ are made of common pasteboard, 3-1/2 inches long,
on a mandril, 1/2 an inch in diameter. They are pasted with ordinary
paste, but mixed with clay, and choaked, and bound as usual.

_Sec. VIII. Of Tourbillon Cases._

This kind of case is generally made 8 diameters long; but, if very
large, seven will be sufficient. From four ounces to two pounds, will
succeed perfectly, but, when larger, there is no certainty. They are
best rolled wet with paste, and the last sheet must have a straight
edge, so that the case may be all of a thickness. After rolling them
in the same manner as wheel cases, pinch them close at one end;
then, with a rammer, drive the ends down flat, and, afterwards, ram
in about one-third of a diameter of dried clay. The diameter of
the former for these cases, must be the same as for sky-rockets.
Tourbillons are to be rammed in moulds, without a nipple, or in a
mould without its foot. (_Ency. Brit._)

_Sec. IX. Of Balloon Cases, or Paper Shells._

First, prepare an oval former, turned out of smooth wood; then paste
a quantity of brown, or cartridge paper, and let it lie until the
paste is quite soaked through. This being done, rub the former with
soap or grease, to prevent the paper from sticking to it. Next,
lay the paper on in small slips, until you have made it one-third
the thickness of the shell intended. Having this done, set it to
dry; and when dry, cut it round the middle, and the two halves will
easily come off: but, observe, when you cut, to leave about one inch
not cut, which will make the halves join much better than if quite
separated. When you have some ready to join, place the halves even
together, and paste a slip of paper round the opening, to hold them
together, and let them dry. Then lay on paper, all over as before,
every where equally, excepting that end which goes downward in the
mortar, which may be a little thicker than the rest; for that part,
which receives the blow from the pounder in the chamber of the
mortar, consequently requires the greatest strength.

When the shell is perfectly dry, burn a vent at the top, with an
iron, large enough for the fuse. This method will answer for balloons
from 4 inches 2/5ths, to 8 inches in diameter; but, if they are
larger, or required to be thrown to a great height, let the first
shell be turned of elm, instead of being made of paper.

For balloons 4 inches 2/5ths, let the former be 3 inches 1/8th, in
diameter, and 5-1/2 inches long. For a balloon of 5-1/2 inches, the
diameter of the former must be 4 inches, and 8 inches long. For a
balloon of 8 inches, let the diameter of the form be 5 inches and
15/16ths, and 11 inches 7/8ths long. For a 10 inch balloon, let the
form be 7 inches 3/16ths, in diameter, and 14-1/2 inches long. The
thickness of a shell for a balloon of 4 inches 2/5ths, must be 1/2 an
inch. For a balloon of 5-1/2 inches, let the thickness of the paper
be 5/8ths, of an inch; for an 8 inch balloon, 7/8ths, of an inch; and
for a ten inch balloon, 1 inch and 1/8th of an inch.

Shells, that are designed for stars only, may be made quite round,
and the thinner they are at the opening, the better; for if they are
too strong, the stars are apt to break at the busting of the shell.
When making the shell, employ a pair of callipers, or a round gage;
so that you may not lay the paper thicker in one place than other,
and also that you may be able to know, when the shell is of a proper
thickness. Balloons must always be made to go easy into the mortars.
(See _Encycl. Brit. Art. Balloon cases_.)

_Sect. X. Of Cases for Illumination Port-fires._

These must be made very thin, of paper, and rolled on formers; from
2 to 3/8ths of an inch in diameter, and from 2 to 6 inches long:
they are pinched close at one end, and left open at the other. When
they are to be filled, put in but a little composition at a time, and
ram it lightly, so as not to break the case. Three or four rounds of
paper, with the last round pasted, will be sufficiently strong for
these cases. (_Ibid._)

_Sect. XI. Of Cases and Moulds for Common Port-fires._

Common port-fires, are intended purposely to fire the works, their
fire being very slow, and the heat of the flame so intense, that, if
applied to rockets, leaders, &c. it will fire them immediately. When
used, they are held in copper sockets, fixed in the end of a long
stick. These sockets are made like port-crayons, only with a screw
instead of a ring.

Port-fires, or _lances of service of the French_, may be made of any
length, but are seldom more than 21 inches long.

The interior diameter of port-fire moulds should be 10/16ths, of an
inch, and the diameter of the former half an inch. The cases must be
rolled wet with paste, and one end pinched or folded down. The moulds
should be made of brass, and to take in 2 pieces lengthwise: when the
case is in the two sides, they are held together by brass rings or
hoops, which are made to fit over the outside. The bore of the mould
must not be quite through, so that there will be no occasion for a
foot. The French make the cases of five thicknesses of paper, and
form the moulds upon rollers of 3/8ths of an inch in diameter.

Port fire, according to the full acceptation of the term _Porte-feu_
of the French, means a _porter_, or carrier of fire, and implies all
sorts of fusées or matches, by which fire is communicated.

In a treatise on _Military Fire-works_, as taught at Strasburg in
1764, an extract of which was translated and published by order
of the War Department in 1800, there are some observations on
port-fires, which, as the mode of making them according to these
directions appears to have been adopted, may be useful to notice in
this place.

"_Port-fires_ may be made in two ways. The first is made and beaten
in a mould; the other simply rolled on a ramrod, and filled lying on
the table.

"To make port-fires of the first kind, the mould must be made of dry
wood, such as pear-tree, nut or box wood. The height of the mould is
13.85 inches; its diameter at the bottom, 3.2 inches; its diameter
above, 2.13 inches; diameter of the hole or caliber, .62 inches;
height of the base, 2.13 inches; its diameter, 3.2 inches.

"The base of the mould has in the middle a nob, which the turner
leaves there, the diameter of which is equal to the whole of the
mould, and one inch high, including the circle, which should be
rounded like a hemisphere. There must be three rods, one of which,
of hard wood to roll the cartridge upon; the two others of iron to
ram down with. The one to roll upon, or the form, is to be of the
length of the mould, exclusive of the handle, which is 3.2 inches
longer. The diameter of this rod is .45 parts of an inch. The first,
or greater one to charge with, is the same length with that to roll
upon; the second is but half the length, and both are .44 parts of an
inch in diameter.

"To make good cartridges, you must have good paper, well sized, cut
according to the length of the rolling rod or form, which must be
rolled very tightly round the form, so that the vacancy left may be
exactly equal to the size of the mould, and that the paper should
exactly fill the space between the form and the mould. Then the form
is drawn out, after having tied it at the end with packthread. To
fill it, it must be replaced in the mould. A cupful of composition is
then put in, and five or six strokes given with the large ramrod. The
ramrod is then withdrawn, and a new charge is put in, which is beaten
like the first, until the cartridge is filled to the height of the
mould. It is then drawn out, and primed with priming powder.

"The port-fire is filled with ease, in using a tunnel placed at the
end of the cartouch, through which you pass the rod.

"_Composition of Port-fires of the first kind._

Saltpetre 4 lbs. 2 oz.
Sulphur 1 12
Priming powder 0 12

"After having mixed these materials well together with the hand, and
then with a rolling pin, you pass them through a hair sieve, and fill
your wooden bowls.

"_The second kind of Port-fires_, are made in rolling strips of paper
3 inches wide, and 1.278 inches long, on a form of hard wood, about
14 inches long, and .35 parts of an inch in diameter. When about
two-thirds of the paper is rolled, the remainder of it is to be
pasted over with paste made of flour and glue. You then finish it,
by passing your hand along the extremity of the pasted paper. Having
finished the number required, you place them in the sun, or near a
stove, and turn them from time to time, to prevent them from sticking
together, or bending.

"Cartridges being well dried, you must fill them with the following
composition. Fold the paper at one of the ends, and at the other,
pour in the composition, placing your cartridge against the
composition; and having placed it perpendicularly on the table, you
give it several strokes, to drive down the composition. Then you
take your iron rod, which is .53 parts of an inch longer than the
one which you use to roll with, and a little less in thickness at
the top. There should be a ring, that it may hang to the finger,
and move the more easily. Having laid your cartridges on the table,
you introduce the rod, and with it compress the composition. Having
withdrawn it, more is put in, it is pressed again, and so on until
entirely full. You will take care to press the last layer of the
composition more than the other, to prevent its falling out by moving.

"The port-fire cartridges being finished, they are laid by for use,
putting ten in a packet as before.

"_Composition of Port-fires of the second kind._

Saltpetre 6 ounces.
Sulphur 2 do.
Priming powder 3 do.

"These three articles being mixed, you will put them in a wooden
bowl, and moisten them with linseed oil, until you find the
composition (being pressed well) is sufficiently hard."

It may be sufficient to observe, that the present improved process of
making port-fires is preferable. (See _Port-fires_.)

_Sec. XII. Of Pasteboard, and its Uses._

The pasteboard, used in pyrotechny, is made of fine white paper, by
joining together five, and sometimes six, seven, and eight sheets of
paper. That which is generally employed, is made of five sheets, and
the other descriptions are employed for large cases. Sized paper is
preferable, having more firmness than the other.

Pasteboard is made in the following way: A paste of flour is first
prepared with hot water, and passed through a hair sieve, to separate
the lumps. A sheet of paper is stretched upon a table, and covered,
by means of a brush, with paste, and a sheet is then laid over it.
This is compressed, and another coat of paste applied; then another
sheet, then paste, and the number is added according to the thickness
required. After five or more sheets are thus pasted together, a dry
sheet is laid over, and the operation is repeated, till five more
are joined. Then a dry sheet is put on, and the pasting is renewed.
By this means, every five sheets are joined together, and the sheet,
thus formed, is kept apart from the rest, by the dry sheet. A pile of
pasteboard, consisting of some hundred sheets, may be made in this
manner at one time. They are then put into a press for the space of
five or six hours, by which they become firmly united, and all the
extraneous paste is pressed out. When a press cannot be had, they may
be put between boards, and heavy weights laid on. The pasteboard is
then hung up in the air to dry, and again submitted to the press, to
remove any inequalities, and to make it smooth.

When glazed paper is used for making pasteboard, we may employ,
alternately, a sheet of brown paper. It is better, however, to use
more of the glazed paper, than of the brown paper. Pasteboard of
three thicknesses will be sufficient for most purposes. It is this
kind, which is used for the heads of rockets.

Several kinds of paper, however, are used in fire-works. For small
preparations, common white paper is sufficient. For port-fire cases,
the common brown paper; for the joints, guarding places from fire,
and covering tubes of communication, any kind of gray paper; and for
covering marrons, the most indifferent kind may be used. Cartridge
paper, as known by that name, may be used for a variety of purposes.

Paper may be rendered incombustible, or nearly so, by soaking it
repeatedly in a strong solution of alum. In the _Literary Journal_
of 1785, of Petersburg, there is a discovery mentioned of a kind
of pasteboard, which neither fire can consume, nor water soften.
It appears that alumina, and its salt (alum) were used in this
preparation.

In the _Journal des Arts et Manufactures_, tom. ii, p. 205, is an
account of the manufacture of pasteboard at Malmedy; and in the
Transactions of the Society of Stockholm for 1785, is a description
of the process for making the Swedish stone paper, which resists
equally fire and water. Stone paper is manufactured in France,
(_Dictionnaire de l'Industrie_, article _Carton_), by taking two
parts of martial earth, (ochre, for instance), and mixing them with
one part of animal oil, and two parts of vegetable matter, previously
made into a pulp. The _British Repository of Arts_ contains several
specifications of patents for the preparation of the same paper.

Although paper may be rendered very difficult of combustion by the
process already mentioned, that of soaking it in a strong solution of
alum, yet to make a paper completely indestructible by fire, it must
be made of amianthus. The process for manufacturing paper with this
mineral, was announced in the _Gazette de France_ in 1778. Professor
Carbury received a medal for the invention.

Incombustible paper, for cartridges, ought to have the property,
not of inflaming, but of simply carbonizing, when exposed to heat.
M. Brugnatelli (_Bulletin des Neustin_) recommends the paper to be
prepared with silicated alkali, commonly called the liquor of flints.
Muriate of potassa, and supersulphate of alumina-and-potassa are both
used for a similar purpose.

Paper made according to Brugnatelli's process, is merely carbonized
by fire, and reduced to powder.

M. Hermbstaedt (_Bulletin des Découvertes_,) observes, that paper,
made with silicated liquor, attracts humidity, and proposes simply a
solution of green vitriol, which has not that property.

Paper may be stained, or coloured, in a variety of ways, as is the
case with the portable Chinese fire-works, that are brought to this
country. Thus, a red paper may be formed by dipping it in a decoction
of brazil wood and alum; yellow, by using fustic; a green, by a mixed
bath of blue and yellow dye, or a solution of copper, &c. Coloured
paper may be glazed with weak size, rubbing it afterwards with a
polished stone.

The Chinese are in possession of several processes, as well for
making, as for ornamenting paper. Their silver paper, which is
sometimes put on their fire-works, is variously figured. The art
is very simple. Two scruples of glue, and one scruple of alum, are
dissolved in a pint of water. This is evaporated, and put on the
paper, where they want it, and finally pulverized _silvery talc_ (a
magnesian stone) is sifted over it. It is then exposed to the sun,
and the extraneous talc is brushed off. The glue, it is obvious,
causes the talc to adhere.

The Abbé Raynal (_Histoire Philosophique des deux Indes_ t. iii,
p. 225) has some interesting facts respecting Chinese paper. Some
useful remarks on paper hangings, paper for decorations, tapestry
paper, &c. may be found in the _Journal de Paris_, 1785, the _Lycée
des Arts_ 1795, and the _Encyclopedie Method. Arts et Metiers_,
t. iv, p. 393. On the formation of paper vases, in imitation of
Japan vases, consult the _Dictionnaire de l'Industrie_, article
_vases_. The different patents, respecting paper, may be seen in
the British _Repertory of Arts_, and the manufacture of paper
generally, in Rees's _Cyclopedia_, and the _Artist's Manual_. The
American improvements are noticed in the latter. Beckman (_History
of Inventions_) has a variety of remarks on the same subject; and,
in his article on paper hangings, &c. vol. ii, p. 161, says, that
artists employed the silver-coloured glimmer (isinglass) for the
covering of paper, and that the nuns of Reichtinstein ornamented with
it, the images, which they made; as the nuns in France, and other
catholic countries, ornamented their _agni Dei_, by strewing over
them a shining kind of talc.

The quality of the paste, which is employed in making pasteboard,
ought to be attended to. The flour should be of rye, and well boiled,
after mixing it uniformly with cold water. Strong bookbinder's paste
has the addition of a fourth, fifth, or sixth of the weight of the
flour, of powdered alum. The _patent paste_ is prepared by extracting
starch from potatoes, in the usual manner, by means of cold water,
and mixing it with mashed potatoes, after they have been boiled, and
boiling the whole in water.

The Japanese cement, or rice-glue, may be advantageously used in many
cases. It is formed by mixing rice flour intimately with cold water,
and then boiling it very gently. It is beautifully white, and dries
almost transparent. We are told, that it is preferable, in every
respect, to the paste made with flour; and its strength is such, that
paper, pasted together with it, will sooner separate in their own
substance than at the joining.

The Chinese, to prevent accidents, and in order that they may fire
their works without injury, and particularly their cases which are
charged with brilliant fire, have a process, for preparing a paste of
a different kind. With the exception of the clay, the same substances
have been employed elsewhere for the like purpose. It consists of
one pound of rye flour, boiled in water; to which is added, a small
handful of common salt, the whole being _thickened_ with finely
pulverized white clay. The pasteboard, we are informed, which is made
with this paste, is not only very solid, but not so susceptible of
inflammation, as that prepared in the usual way.

A Chinese paste is announced in the _Bulletin de la Société
d'Encouragement_, 1815, which is very economical, and used with
success. It is made by mixing ten pounds of bullock's blood, with one
pound of quicklime, and occasionally flour.

_Sec. XIII. Of the Pulverization of Substances._

Various substances are employed either in grain, laminæ, filings, or
impalpable powder. When treating of nitre, sulphur, and charcoal, and
other bodies, we mentioned the processes for reducing them to powder.
It will be sufficient here to remark, that cannon powder, when it
is converted into fine powder, takes the name of meal-powder; the
conversion being effected, by beating it in a leather sack, already
described, by rolling it upon the mealing-table, or by the action
of a wooden pestle in a mortar. It is then passed through a fine
sieve. The sack is said to be a preferable mode, as nearly the whole
of it becomes pulverized. Saltpetre, sulphur, charcoal, antimony,
&c. may be reduced to powder in a mortar of cast-iron, marble, or
wood. The best method of pulverizing saltpetre is given under that
article, which consists in boiling it in a copper, and stirring it
continually at the end of the process. The best mode of pulverizing,
or bringing cast-iron to a state of fineness, is mentioned in the
article on _Iron_. Some of the metals, as iron, zinc, the alloy of
copper and zinc, (brass,) &c. are brought to a sufficient fineness
by the file. The filings, if so required, may be afterwards sifted.
Zinc, when in small pieces, may be pulverized, by means of a steel
mortar and pestle. It may be granulated, by suffering it to run, when
melted, through an iron cullender into water. For the pulverization
of camphor, see that article.

_Sec. XIV. Of Mixtures._

All compositions for fire-works, are generally made at first in
mortars, and the mixture is then finished by passing it through
a sieve; it being returned to the sieve, and again sifted. This
operation is sometimes repeated several times. Of all compositions,
that for sky-rockets requires to be most intimately blended.

To receive the sifted matter, leather or parchment is used; but, in
lieu of either, pasteboard, or several sheets of paper, cemented
or glued together will answer. It is obvious, that, in preparing
mixtures, of two, three, or four articles, they should not only be
very fine, but uniformly and intimately mixed.

Several receivers, made by stitching leather over a rim, in the
manner of a sieve, would be found very convenient; but wooden bowls,
and copper basins, are generally used.

Some ingredients must be passed through a lawn sieve, after having
been previously incorporated. A receiver, with a top, is the kind
of sieve to be preferred. The composition for wheels, and common
works, need not be so fine as for rockets. But in all fixed works,
from which the fire is to play regularly, the ingredients must be
very fine, and great care taken in mixing them together; and in those
works, into the composition of which, iron and steel enter, the hands
must neither touch them, nor moisture be suffered to come in contact.
In either case, they would be apt to rust.

PART III.

FIRE-WORKS IN GENERAL.

CHAPTER I.

OBSERVATIONS ON FIRE-WORKS.

In Europe, the invention of fire-works is of a recent date, and
ascribed to the Italians. In China, however, fire-works have been
known for centuries. Some recent exhibitions at Pekin prove, that
the Chinese have attained to a degree of perfection, not surpassed
by the artists of France, Italy, or England. The observations of Mr.
Barrow, (_Travels in China_), on this subject are worthy of notice.
"The fire-works, in some particulars," says he, "exceeded any thing
of the kind I had ever seen. In grandeur, magnificence, and variety,
they were, I own, inferior to the Chinese fire-works, we had seen at
Batavia, but infinitely superior in point of novelty, neatness, and
ingenuity of contrivance. One piece of machinery I greatly admired;
a chest five feet square, was hoisted up by a pulley, to the height
of fifty or sixty feet from the ground: the bottom was so constructed
as then, suddenly, to fall out, and make way for twenty or thirty
strings of lanterns, enclosed in a box, to descend from it, unfolding
themselves from one another by degrees, so as, at last, to form a
collection of full 500, each having a light of a beautifully coloured
flame, burning brightly within it. This devolution and development of
lanterns was several times repeated, and, at every time, exhibited a
difference of colour and figure. On each side, was a correspondence
of smaller boxes, which opened in like manner as the others, and let
down an immense net-work of fire, with divisions and compartments of
various forms and dimensions, round and square, hexagons, octagons,
&c. which shone like the brightest burnished copper, and flashed like
prismatic colours, with every impulse of the wind. The diversity
of colours, with which the Chinese have the secret of clothing
fire, seems one of the chief merits of their pyrotechny. The whole
concluded with a volcano, or general explosion and discharge of suns,
stars, squibs, crackers, rockets, and granadoes, which involved the
gardens for above an hour in a cloud of intolerable smoke."

Thevenot (_Travels in the Levant_) says, that during the bairam,
or carnival, which takes place with a great deal of ceremony, the
sultan causes fire-works to be played off all night; the sultan
and sultanas diverting themselves with these and other amusements.
Dr. Pococke (_Travels through Egypt_), says, that at Cairo, when
the Nile is high, besides aquatic excursions, concerts of music,
and other diversions, fire-works form a part of those pleasures
and recreations. In a _Description of the East Indies_, fire-works
are stated to be often exhibited at the marriage of the Banians or
Gentoos.

With respect to the arrangement and display of sundry pieces of
fire-works, either alone or combined, the effect depends, as well
upon the ingredients, which compose the several sorts of fire, as
on the taste displayed in their exhibition. It would be altogether
unnecessary to notice, at this time, the order of exhibition usually
adopted, reserving this subject until we have gone into the various
preparations, which constitute, as it is called, a _system of
fire-works_. In order, however, to become familiar with the manner of
arranging them, as well as with their composition and preparation,
whether designed for a general or a partial display, for the open air
or for rooms, we purpose to appropriate distinct chapters for their
consideration.

The variety of preparations, which become necessary where a full
exhibition is intended, the accuracy of the different mixtures, and
the adjustment of cases to wheels, whether vertical or horizontal,
and the arrangement of the leaders, or communicators of fire, from
one part to another of the work, with many other circumstances, in
relation to stars, rain, &c. all require, from the artist, particular
care and attention.

For the mere exhibition of one or two pieces, as a plain rocket,
rocket with serpents, or the like, and likewise for some exhibitions,
on water, called aquatic fire-works, in rooms or apartments, with
scented fire, or on the stage; the preparations are by no means
extensive.

It is, therefore, our design to present a view of the whole
subject in detail, and to speak of the different combinations
of arrangement, which are made according to fancy and taste, and
calculated, as we have remarked, either for small or extensive
exhibitions.

We have, in a preceding part of this work, made some observations
on certain preliminary operations; on the various sizes and charges
for cases; on the paper, necessary to be used, for different kinds
of cases; and, generally, on sundry manipulations, connected with
the making, filling, and preparation of sundry descriptions of
fire-works. It remains, therefore, in the course of this subject,
to give the several formulæ, with such observations as immediately
concern the subject; and for this purpose we will pursue the
following order:

Frazier is of opinion, that the arrangement of fire-works, which
have been exhibited with effect, may, on particular occasions, be
established as a guide. For this reason, Morel introduces an account
of the celebrated fire-works at Versailles and Paris, in 1739, which
we shall here notice.

_Exhibition of fire-works at the city house of Paris, on occasion of
the peace in 1739._

The theatre was a building, forty feet square, with a pyramid of
eighty feet in height, on which was placed a globe, containing
artificial fire, and accompanied with sixteen large vases of
different forms.

All the edifice was ornamented with a variety of decorations,
combined with figures and emblems of peace, and painted on marble.

After several guns were fired, as a signal, the exhibition commenced,
with the discharge of a large number of _honorary rockets_, fired
three and three at a time. Nearly five hundred _lances_, and
_saucissons_ garnished, lighted the four sides of the body of the
works. Thirty cases of artificial fire, furnished with _fusées_,
and double _marquises_, were placed upon the large terrace, with
1200 _pots à feu_ (fire-pots); and upon the ballustrade of the same
terrace, forty _jets_, twenty of which were _aigrettes_, and eight,
revolving suns, four in the middle, and four on the angles. Four
large fixed suns were placed above the four which revolved, and four
_pattes d'oies_, (_geese feet_,) were situated before the grand
pedestal of the pyramid, with _jets_, and _pots_ with _aigrette_.

At the foot of the pyramid, on the steps, were placed 1200
_fire-pots_, and upon the pedestal of the pyramid, twelve large pots
of _aigrette_, on the extremity of which, were arranged _aigrettes_
in groups, and three large luminous stars, formed of two hundred
fire lances. The four faces of the pyramid were lined with about
fifty other _jets_; after which there were cascades, or fountains
of fire. The first horizontal wheel was composed of, or furnished
with, six cases, and contained also two hundred and forty double
_marquises_. The second wheel contained two hundred and forty
_fire-pots_, and six cases, with upwards of three hundred _fusées_,
all in stars, twelve air balloons in the middle, but placed at the
bottom of the fire-work. To this was added, twelve artificial bombs,
fixed in mortars, and placed near the cannon, which pointed to the
works.

This outline of the brilliant exhibition of fire-works in 1739, will
give the reader some idea of the taste and magnificence of the work
at that period. We may here add, however, that the improvements,
which have since taken place, both in the composition of artificial
fire, and its arrangement, are such as to place the modern
exhibitions of this kind far above that we have just spoken of. But
the following account of the execution of fire-works, performed on
the _Pont Neuf_, in August of the same year, is more extensive, as
the exhibition appears to have been more grand.

The theatre, which represented the temple of Hymen, was an edifice
of the doric order. It was square. A gallery of five hundred feet in
length was supported by thirty-two columns, four feet in diameter,
and thirty-three feet in height. In the interior, were two solid
bodies, and also one or more stair cases. At the two sides of this
temple, along the parapets of the _Pont Neuf_, were thirty-six
pyramids, eighteen of which were forty feet high, and the others,
twenty-six feet. They were joined by what is called, in architecture,
a _corbil_, and carried vases on their summits.

The signal for the exhibition was given by the firing of cannon.
Immediately, were seen, rising into the air from each side of the
temple, three hundred rockets, fired twelve at a time. They were
discharged from the eight towers of the _Pont Neuf_, which face the
Tuileries, and were succeeded (upon the same towers,) by one hundred
and eighty _pots of aigrette_. The _Chinese trees_ were disposed in
such a manner, as to form a pyramid. A succession of _Chinese trees_
now appeared, immediately on the tablet of the cornice of the bridge;
then followed a great _fixed sun_, sixty feet in diameter, which
appeared in all its splendour, in the midst of surrounding objects.
Under this, was placed a large _illuminated cypher_, thirty feet
in height, which consisted of different colours, in imitation of
jewels. At the sides, between the pillars of the temple, were also
two other artificial _cyphers_, six feet high, and composed of _blue
fire_, which had a surprising effect. There were placed upon the two
walks of the bridge, on the right and left of the temple, beyond the
illuminated pyramids, two hundred cases of _fusées de partement_,
of five or six dozen each. These cases were fired, five at a time,
and succeeded the rockets. They began, on each side, from the first
near the temple, and in succession, as far as the extremities to
the right and left. There appeared then cascades of _red fire_,
issuing from the five arches of the bridge, which seemed to pierce
the illumination, and so vivid was the light, that the eye could
scarcely sustain it. The combat of the _dragons_ next ensued; and
the _water-fire_, or aquatic fire-works, covered almost the whole
surface of the river. Eight _boats_, containing works for the display
on water, were arranged in symmetrical order, with the _boats of
illumination_. There were also thirty-six _cascades_ or fountains
of fire, about thirty feet high, which appeared to rise out of the
water. This exhibition of the cascades, was preceded by a revolving
_water-sun_, and a discharge of _stars_ from one hundred and sixty
pots of _aigrettes_, which were placed at the lower part of the
terrace.

Four large boats, containing aquatic fire-works, were moored near the
arches of the bridge, and four others were disposed on the side next
to the Tuileries. The fire-works, which they contained, consisted
of a great number of large and small casks, charged with _gerbes_
and _pots_, which, when discharged, filled the air with _serpents_,
_stars_, &c. There was, also, a large number of _hand gerbes_, and
revolving _water-suns_.

When the exhibition of the cascades was finished, the grand
chandelier, composed of six thousand _fusées_, and resting on the top
of the temple, was lighted. Both extremities were set on fire at the
same time. This was followed by two smaller chandeliers, previously
placed on each side of the foot-way of the bridge, and containing
five hundred _fusées_ each.

The fire-works, exhibited at Versailles, in the same year, and on the
same occasion, were also magnificent. The account we have of them
is the following: There was a large building erected, representing
the temple of Hymen, nine hundred feet in length, and one hundred
and twenty in height, in the gardens of Versailles, in front of the
grand gallery. It was in the form of a portico, with re-enterings and
salients at the two extremities, which faced the two great basins;
and, in the centre, were illuminated works.

The forges of Vulcan, in the grottos, commenced with the sound of the
hammers of the Cyclops. The sparks, then produced, covered, in a few
instants, the two basins, provided for the purpose, with an apparent
sheet or volume of fire.

From the summit of a rock, came out a _jet_ of brilliant fire, more
than thirty feet in height, accompanied with four others of less
elevation, representing torrents of fire as from volcanoes. To this
succeeded a great _jet_ of water, forty-five feet in height, leading
with it, as it were, seventeen other _jets_, which surrounded the
rocks, and rushing forth with avidity, produced, in appearance, a
mixture of flame and water, which, in the end, consumed entirely the
two grottos.

After this, the fire-works, behind the decoration, were exhibited.
Two hundred and fifty _boxes_, and as many caissons, arranged on
both sides of the turf, which descended to the grass, were first
exhibited. This, however, was less brilliant than the fire from
the Cyclops. To this succeeded a brilliant fire, placed before the
illumination. This composition, elevating itself to a mean height,
pleased equally by its form, as by its brilliant whiteness. This
fire composed three distinct decorations, which succeeded as the one
replaced the other, following the same order. The spouting waters,
which decorated the gardens, together with the artificial fire,
appeared in the form of cascades and fountains. The first decoration,
at the head of the two great basins, exhibited two handsome cascades,
in the form of a white sheet, and surmounted with an _aigrette_
twenty-five feet in height. This was accompanied with two _pattes
d'oies_ (_geese feet_) of seven _jets_ each, and accompanied also
with fifty _jets_ playing from each of the sides, twenty feet in
height, and occupying the fore ground.

The second appeared under the form of the _pattes d'oies_, of eleven
jets each, of which four, at the head of the basins, were large,
and all projected a body of fire, fifty feet in height. They were
intermixed, however, with the pots of _aigrettes_, twenty feet in
height, which threw a crown, composed of stars, &c. to the height of
fifty feet, which produced in the atmosphere a lively and brilliant
light.

The third represented thirteen fountains of fire, twenty-five feet in
height, and thirty feet in diameter, with an _aigrette_ in each. In
these, there were six circular, and six spiral fountains. The largest
was placed between the two basins, with four others on the right and
left.

The fountains, which represented the combat of animals, had in each
of them two. The animals threw, at the same time, jets of water and
fire, and, between each of the fountains, large brilliant jets or
spouts. This part of the exhibition was finished, by throwing into
the air the _garnishing_ or furniture of the pots, which produced
crowns, &c. of great splendour.

To these three decorations, succeeded the exhibition of twelve
_Italian pots_, placed six in a row, and in the middle of two great
basins, which produced repeated discharges.

The whole was then closed by setting fire to two great chandeliers,
which were placed behind the grand decoration, and contained more
than three thousand _fusées_.

It appears from history, that when Henry II, entered Rheims, there
was a representation of several figures in fire; and in 1606, the
duke of Sully made an exhibition of fire-works at Fontainbleau;
and in 1612, Morel, commissary of artillery, prepared a splendid
exhibition of the same kind. It appears, also, that the art of
communicating fire from one piece of fire-work to another, as in the
combined piece of nine mutations, and the pyric-piece (which will be
noticed hereafter) was discovered by Ruggeri, artificer to the king,
at Boulogne, in France, in 1743.

It may not be improper, in concluding this article, to notice, in a
general manner, the exhibition of the works of fire by the ancients.

The fire-works of the ancients consisted, for the principal part, of
illuminations, and the use of some particular descriptions of fire.
They were, however, very imperfect. Since the invention of gunpowder,
its effects as well as its modifications, in this particular, became
known; and, so far as respects the various preparations of artificial
fire, gunpowder itself has produced a new era in pyrotechny, and the
various modifications, to which it is subject, have occasioned a
great variety of fire-works.

According to the authority we have on the subject, it appears, that
the ancients, in exhibiting their preparations of fire, set them off
by the hand, and directed them among the people, which produced great
eclat.

Another description of fire-work was designed expressly for the
theatre, part of which was exhibited in the form of man or beast.
Of their theatrical works, our accounts are imperfect. Their works,
generally, were formed of _lardons_, _stars_, and _fire-balls_, in
imitation of _grenades_, and _flying fusées_ or _rockets_. That they
neither had a system in arranging, nor regularity in exhibiting their
works, is evident from a variety of circumstances; for, although the
number of their pieces, such as they were, was great; yet, they
so crowded them upon each other, as that, when they were fired,
they frequently destroyed the persons in their vicinity. An author
of antiquity observes, that "he has seen a great many artificial
machines, but, to speak the truth, few which have succeeded; and it
is commonly after acclamations of joy, that the spectacle is finished
by the destruction of some, and the wounding of a great number."

This fact is not at all surprising; because their works were prepared
in wooden tubes, at least among the more modern, as paper cases
were not then known. These tubes, moreover, were not secured by any
covering, and were the more likely to burst, and hence accidents
were common. The moderns, however, have rejected altogether the use
of wood, in the formation of cases, and have availed themselves of
the use of paper, which can be made of any size or thickness. (See
_Pasteboard_.)

Notwithstanding wood is not employed by experienced fire-workers,
partly in consequence of the reasons just given, and partly because
paper furnishes a material in every way adapted to the purpose;
yet, within a few years past, reed has been used in Spain, which,
however, is secured by cloth and pack thread. Such substitutes,
nevertheless, besides being more or less dangerous, have nothing to
recommend them. It is a fact, that the Chinese, who undoubtedly excel
in the manufacture of fire-works, if we believe the authority of the
English embassy, use altogether paper cases; but in the _war-rocket_,
employed by the natives against the British at _Seringapatam_, which
did, according to the English account, great execution, their cases
were formed entirely of sheet-iron. In their smaller works, which are
prepared expressly for sale, paper cases are altogether made use of.

CHAPTER II.

FIRE-WORKS FOR THEATRICAL PURPOSES.

_Sec. I. Of Puffs, or Bouffées._

The _bouffée_, according to the term used in French, signifies a
species of fire, which exhibits itself in _puffs_, or in alternate
appearances, more or less brilliant. It is also called the flambeaux
of the furies. This description of artificial fire is used in
_theatres_, and frequently in ordinary fire-works. It is fired from,
and exhibited with, a funnel of tin, or sheet iron, having a hole at
the apex of the cone. The hole is to be sufficiently large to admit
the fire from a quick match. It is particularly calculated, when a
gulf, crater, or the caves of the Cyclops, intended to eject flame,
are to be exhibited.

Although many compositions may be used for this purpose, yet the
following, which is employed in France, is considered preferable:

_Composition for Bouffées._

Saltpetre 16 oz.
Meal-powder 4 oz.
Charcoal 8 oz.

When the materials are well mixed, a piece of silk paper is prepared
in a round shape, by pressing it on the end of a roller, in the same
manner as the ordinary cases. About one ounce of the composition
is put into it, on which is placed very lightly two drachms of
meal-powder. A double quick-match is now put on the meal-powder, and
the paper is closed by pressing it between the fingers. It is then
tied with twine. The quick-match is left sufficiently long to pass
through the hole at the apex of the cone, in which is introduced
the _puff_, being pressed a little at the bottom. The excess of the
quick-match, should there be any, is cut off within an inch of the
extremity of the funnel. When used, it is inflamed by a lance or port
fire. The effect of the puff, in the first place, is to throw out of
the funnel, by the meal-powder, a volume of fire, which will cause
the appearances before mentioned.

_Sec. II. Of Eruptions._

If the appearance of a volcano, or the effect of a mine is required
in a piece, the following method is commonly followed: a tin,
sheet-iron, or brass box is provided, either round or square, of nine
inches in height, and three inches and a half in diameter, and placed
on a wooden stand, sufficiently large to prevent it from overturning.

Three, four, or five ounces of the composition, mentioned in _Sec.
i._ of this chapter, is put into it, according to the effect intended
to be produced. The composition is pressed a little with the hand,
and a piece of quick-match is used. This match projects out of
the case, and is secured with a piece of paper, pasted over its
circumference.

When the fire is presented to the quick-match, it communicates
with rapidity to the inside of the box, or case, which produces an
eruption, from twelve to fifteen feet in height. The effect may be
made more or less great, by making the boxes of a proportional size,
or by using several of them at the same time.

If a mine is the subject of representation, it is necessary to employ
some large _marrons_, which should communicate with the boxes, and in
such a manner, as that they may operate at the same time.

This exhibition, it is obvious, may be varied according to
circumstances, either by employing a larger quantity of the
composition in several cases, or by using one or more marrons,
or some other descriptions of fire-works, the effect of which is
calculated to increase the flame, and to produce the necessary
variations.

_Sec. III. Of the Flames._

If a flame is to be represented, as for example, the effect of an
incendiary, and its appearance is to be prolonged, the fire from tow
being too transient, small iron kettles, of four inches in diameter,
and depth, may be used. In these are put three or four ounces of the
composition of the _lances of service_, which is moistened with the
oil or spirit of turpentine. When set on fire, they will produce a
blaze three or four feet in height, and one and a half in diameter.
Several may be used, according to the effect required. See the
composition for the _lances of service_.

_Sec. IV. Of the Fire-rain._

A variety of compositions for fire-rain are used, which will be
noticed, when we speak of the _garnishing_ of rockets, and other
fire-works.

Cases are prepared of seven-twelfths of an inch in diameter, and ten
inches long, which are choaked in such a manner, as that the hole of
communication should be one-third of the diameter of the interior
case. They are then charged with the following composition:

_Composition of the fire-rain._

Saltpetre 8 ounces.
Sulphur 4 do.
Meal powder 16 ounces.
Charcoal of oak 2½ do.
Pitcoal 2½ do.

When the cases are charged and primed, they are tied upon a rod,
having a groove cut in its length. In the inside of the groove, is a
port-fire, or leader, which is tied to the cases with twine, and the
groove is then covered with several pieces of paper, in the shape of
a band.

This precaution is thus taken for the theatre, in order to prevent
the inflamed port-fire from falling on the stage.

_Sec. V. Of other Compositions for Fire-rain, in Chinese fire._

The composition of Chinese fire, which we will have occasion to
mention more fully hereafter, is calculated to exhibit a more
brilliant fire, with a steady and uniform effect. It is used
principally on the French stage, in large operas. It is charged and
used, in all respects, like the preceding.

_Composition of Chinese Fire._

Saltpetre, 8 ounces
Meal powder, 16
Sulphur, 4
Charcoal, 2
Powdered cast iron, 10

The elegance of the flame, produced by this mixture, depends entirely
upon the effect, which cast iron possesses; and, by its combination
with charcoal, sulphur, meal powder, and nitre, while an oxide of
iron results from the combustion, we have, likewise, other products,
arising from the decomposition of the nitre, and the union of carbon
and sulphur respectively with a part of the oxygen of the nitric
acid of the nitre. The gunpowder decomposes itself by reason of the
nature of its own composition; but the sulphur, charcoal, and iron,
decompose the nitric acid of the nitre, in the act of combustion. So
that, to produce the effect, an additional quantity of nitre to that
which is in the gunpowder, is required in this preparation.

_Sec. VI. Of Thunderbolts. (Foudres F.)_

The thunderbolts are charged in cases of two-thirds of an inch in
diameter, in the same manner as cases for wheels and rockets. They
are primed, whitened, well pasted, and left to dry. Some preliminary
operations are required in their exhibition, as the use of the
piercer, the tying of one end of the case, which is to descend first
from the top of the theatre, &c. A port-fire is used for setting them
off.

_Composition of Thunderbolts._

Meal powder, 6 ounces.
Saltpetre, 6 ----
Sulphur, 3 ----
Antimony, 4 drachms.[24]

_Sec. VII. Of Dragons and other Monsters._

In certain pieces, exhibitions of this kind are made. They are formed
in such a way, as to make them throw fire from the mouth, nose, and
ears, which is blown out into the air. Cases, charged with brilliant
fire, are so arranged that their fire may act all at the same time.
Puffs may also be produced to go out at the mouth, by means of a
tube or funnel, placed behind the monster. These preparations and
exhibitions are so susceptible of variations, that, having a previous
knowledge of the composition and effect of the fire-work, it may be
so arranged as to produce a variety of appearances.

_Sec. VIII. Of Lightning._

The effect of lightning may be shown by several preparations.
Lycopodium, or puff-ball, is the substance most commonly employed.
When it cannot be procured, rosin may be substituted; and, generally,
as the latter is cheaper, it is used. Rosin, reduced to an impalpable
powder, and thrown upon a flame, will produce the effect in a
remarkable degree, and when blown through a tube, the effect is more
striking.

Several fluid substances, when ejected from a syringe on a lighted
candle, have the same appearance. Alcohol has this effect. The
difficulty of preparing and employing them, has given the lycopodium
a preference.

A tin or brass tube, larger at one end than the other, and covered
at the former end, with a cover, perforated with holes, similar to
the branch of a watering pot, is used for holding the composition,
or substance made use of. Through this cover, or lid, a cotton wick
is put, which, before lighting, is well soaked in alcohol or spirits
of wine. When lighted, the torch or tube, containing the lycopodium,
or rosin, is shaken at the smaller extremity; when these substances
will pass through the holes in small quantities, and be successively
inflamed.

_Sec. IX. Of the Artifice of Destruction._

When, in any exhibition, palaces, castles, or forts are to be
demolished, or thrown down, there are about twenty petards fixed
on rods. Petards, for this use, are made with cases, and sometimes
with wheels. The cases are generally three-quarters of an inch in
diameter, charged with grain powder, and choaked at both ends. They
are arranged in a zigzag direction.

This series of _crackers_ has a fine effect. It is obvious, that,
in all these exhibitions, intelligent artizans may employ various
descriptions of artificial fire, where, in particular, it often
seems, that there is something yet to be wished for.

_Sec. X. Of the Spur-fire._

The spur-fire is so called, because its fire or sparks resemble the
rowel of a spur. It is used in theatres and in rooms. It is the most
beautiful of any yet known, and was invented by the Chinese, but
greatly improved in Europe.

It requires great care to make it properly. Care ought to be taken
that all the ingredients are of the best quality, that the lampblack
is neither damp nor clodded, that the saltpetre is the best refined,
and the sulphur perfectly pure. This composition is generally rammed
into one or two ounce cases, about five or six inches long, but not
driven very hard; and the cases must have their concave stroke struck
very smooth, and the choak or vent not quite so large as the usual
proportion: this charge, when driven, and kept a few months, will be
much better than when rammed. If kept dry, it will last many years.

As the beauty of this composition cannot be seen at so great a
distance as brilliant fire, it has a better effect in a theatre or
room, than in the open air; and may be fired in a chamber, without
danger. Its effect is of so innocent a nature, that it has been
called _cold fire_; and so extraordinary is the fire produced from
this composition, that if well made, the sparks will not burn a
handkerchief when held in the midst of them. The hand, brought in
contact with the spark, will feel only a sensation similar to that
occasioned by the falling of rain. When any of these spurs are fired
singly, they are called _artificial fire-pots_; but some of them,
placed round a transparent pyramid of paper, and fired in a large
room, make a very elegant appearance.

_Composition of Spur-Fire._

1. Saltpetre, 4½ lbs.
Sulphur, 2 lbs.
Lampblack, 1½ lbs. or,
2. Saltpetre, 1 lb.
Sulphur, ½ lb.
Lampblack, 4 quarts.

The saltpetre and sulphur must be first mixed together, and sifted,
and then put into a marble mortar, and the lampblack with them, which
are to be worked by degrees, with a wooden pestle, till all the
ingredients appear of one colour, which will be a gray, approaching
to black. It is then to be tried by driving a little of it into a
case, and fired in a dark place; and if the sparks, which are called
_stars_, or _pinks_, come out in clusters, and afterwards spread
well, without any other sparks, it is a criterion of its goodness.
If any drossy sparks appear, and the stars are not full, it is then
not mixed sufficiently: but, if the pinks are very small, and soon
break, it is a proof that it has been rubbed too much; for, in this
case, few stars will appear. When, on the contrary, the mixture is
not rubbed sufficiently, the combustion will be too weak, and lumps,
resembling dross, with an obscure smoke, but without stars, will be
emitted.

The peculiar effect of this composition is owing to the carbon of
the lampblack, one part of which is inflamed, its combustion being
supported by the oxygen gas of the atmosphere.

_Sec. XI. Of the coloured Flame of Alcohol._

We have already remarked, in treating of alcohol, that its flame may
be changed of various colours, by using certain native substances.
See _Alcohol_.

Alcohol, thus mixed, or combined with substances, may be exhibited
on certain occasions; for even cotton, when immersed in it, and
set on fire, will show the same appearances. Morel remarks, that,
if vinegar, a small portion of crude tartar, and common salt,
and a still smaller quantity of saltpetre, be mixed together,
and distilled, a liquid will be obtained, which burns with great
brilliancy. It is doubtful, however, if we judge from analogy,
whether either tartar, the salt, or saltpetre, will communicate
any peculiar property to the distilled vinegar; for these saline
substances will remain unaltered in the distilling vessel. The
vinegar, nevertheless, may be obtained in a more concentrated state,
being deprived of its colouring and other matter, and the greater
part of its water, and, therefore, approach to the state of acetic
acid.

With respect to alcohol, it is known to dissolve a variety of saline
substances, most of which have the property of changing the colour of
its flame. Although we have not made any experiments with the spirits
of turpentine, yet we are of opinion, that it may be used with
resins, &c. in the same manner. In all cases, it is evident, that the
fluid made use of must be inflammable.

_Macquer_ (_Memoirs of the Turin Academy_) made a number of
experiments on the solubility of salts in alcohol, and on the
different coloured flames, which they produced. The principal results
of his experiments, are the following:

Quantity in grains. Salts soluble in 200 Peculiar phenomena
grains of spirit. of the flame.

{ Flame, larger, higher,
4 Nitrate of potassa, { more ardent, yellow,
{ and luminous.

5 Muriate of potassa, { Large, ardent, yellow,
{ and luminous.

0 Sulphate of soda, Considerably red.

15 Nitrate of soda, { Yellow, luminous,
{ detonating.

0 Muriate of soda, { Larger, more ardent,
{ and reddish.

0 Sulphate of ammonia, None.

108 Nitrate of ammonia, Whiter, more luminous.

24 Muriate of ammonia, None.

288 Nitrate of lime, { Larger, more luminous,
{ red, and decrepitating.

288 Muriate of lime, { Like that of nitrate of
{ lime.

84 Nitrate of silver, None.

204 Muriate of mercury, { Large, yellow, luminous,
{ and decrepitating.

4 Nitrate of iron, Red and decrepitating.

36 Muriate of iron, { More white, luminous,
{ and sparkling.

{ More white, luminous,
48 Nitrate of copper, { and green, much smoke.
{ The saline residuum
{ became black and burnt.

48 Muriate of copper, { Fine green, white
{ and red fulgurations.

The alcohol, he employed, had a specific gravity of 0.840.

_Sec. XII. Of Red fire._

Dr. Ure (_Chemical Dictionary_) informs us, that the beautiful red,
which is now frequently used at the theatres, is composed of the
following ingredients: 40 parts of dry nitrate of strontia; 13 parts
of finely powdered sulphur; 5 parts of chlorate (hyperoxymuriate)
of potassa, and 4 parts of sulphuret of antimony. The chlorate of
potassa and sulphuret of antimony, should be powdered, separately,
in a mortar, and then mixed together on paper; after which they may
be added to the other ingredients, previously powdered and mixed.
No other kind of mixture than rubbing together on paper is required.
Sometimes a little realgar is added to the sulphuret of antimony, and
frequently, when the fire burns dim and badly, a very small quantity
of very finely powdered charcoal or lampblack will make it perfect.

CHAPTER III.

OF PORTABLE FIRE-WORKS.

_Sec. I. Of exhibitions on Tables._

Fire-works, it is obvious, may be employed in a variety of ways,
either large or small, in the open air, or in apartments, according
to circumstances. _Fire-tables_ are composed of a great many
works, the same as is exhibited upon a large scale; but of a size
corresponding with small exhibitions. As _fire-tables_ are used only
in apartments, and the works are shown from tables, on which they are
arranged, it is necessary that the cases which contain them should be
of a small caliber, and their fire less extensive.

The cases or cartridges are made of one-eighth of an inch in
diameter, and charged with the best pistol powder, which produces
less _smoke_ than cannon powder. These small works are usually
exhibited on pasteboard, differently arranged.

Among the works are frequently figures, resembling fruit contained
in _gerbes_ and even small _caprices_. _Pinks_, which are also used,
are generally modified, or accompanied with other decorations, and
furnished with illuminated suns. _Fire-pots_ of one inch in diameter,
filled with small _bombs_ and various devices, are employed, when a
_surprise_ is intended. The fire-table is arranged, although upon a
small scale, in the same manner as other works. Their arrangement,
therefore, is the same as for other kinds of fire-works, only
proportioning them accordingly.

_Brilliant fire._

Meal powder, 16 oz.
Fine filings of steel. 2½ do

_Jessamine._

Meal powder, 16 oz.
Saltpetre, ½ --
Sulphur, ½ --
Fine steel filings, 2½ --

_Aurora._

Meal powder, 16 oz.
Gold powder, 2 --

_White._

Meal powder, 16 oz.
Saltpetre, 6 --
Sulphur, 10 --

_Rays._

Meal powder, 16 oz.
Needle filings, (or filings of the best steel,) 1½ --

_Silver rain._

Meal powder, 16 oz.
Saltpetre, ½ --
Sulphur, ½ --
Needle filings, (or filings of the best steel,) --

_Chinese silver rain._

Meal powder, 18 oz.
Sulphur, 2 --
Saltpetre, 1 --
Powder of cast iron, of the best, 5 --

As to _aquatic fire-works_, some of which are frequently shown in
rooms, the reader will find in the article on that subject, a full
account of the manner of forming them. He may also consult a treatise
on _Artificial fire-works_ by Perrint D'Orval, published in 1745.
This work gives ample instructions for performing all kinds of
fire-work on water.

In the article alluded to will be found several formulæ for preparing
odoriferous fire, which may be used for exhibitions on the table. The
succeeding chapter, however, is sufficiently comprehensive on that
subject.

_Sec. II. Of Table Rockets._

Table rockets are not calculated for exhibition. They are designed
merely to show the truth of driving, and the judgment of a
fire-worker. They have no other effect, when fired, than spinning
round in the same place where they began, till they are burnt out,
and showing a horizontal circle of fire. The method of making these
rockets, is the following: Have a cone, turned out of solid wood,
2-1/2 inches in diameter, and of the same height, and, round its
base, draw a line. On this line, fix four spokes, two inches long
each, so as to stand one opposite the other; then fill four nine-inch
one pound cases with any strong composition, within two inches of the
top. These cases are made like tourbillons, and must be rammed with
the greatest exactness. The rockets being filled, fix their open ends
on the short spokes; then, in the side of each case, bore a hole near
the clay. All these holes or vents must be so made, that the fire of
each case may act the same way; and from these vents carry leaders to
the top of the cone, and tie them together. When the rockets are to
be fixed, set them on a smooth table, and light the leaders in the
middle, and all the cases will fire together, and spin on the point
of the cone. These rockets may be made to rise, like tourbillons, by
making the cases shorter, and boring four holes in the under side of
each, at equal distances. This being done, they are called double
tourbillons.

All the vents in the under sides of the cases, must be lighted at
once; and the sharp point of the cone cut off, at which place, it is
to be made spherical.

_Sect. III. Of the Transparent Illuminated Table Star._

The table star is usually twelve feet in diameter, and, from the
nearest extremity to the frame, four feet. This proportion, observed
on each side, will make the centre frame four feet square. In this
square, a transparent star is fixed. This star may be painted blue,
and its rays made like the flaming stars. The wheels for this star
may be composed of different coloured fires, with a charge or two of
slow fire. The wheels, on the extremities, may be clothed with any
number of cases; so that the star-wheel consists of the same. The
illuminated fires, which must be placed very near each other on the
frames, in order to have a proper effect, ought to burn as long as
the wheels, and be lighted at the same time.

_Sect. IV. Of Detonating Works._

We have noticed various fulminating preparations in different parts
of our work, such as the ordinary fulminating powder, Higgins's
fulminating powder, fulminating oil, and several metallic powders. We
have also given some preparations made with fulminating silver, the
making of which we have noticed.

Besides the torpedo, &c. prepared with fulminating silver, there
are some other preparations made with the same substance, which we
purpose to give in this place.

_Waterloo crackers._ Take a slip of cartridge paper, about
three-quarters of an inch in width, paste and double it. Let it
remain till dry, and cut it into two equal parts in length, (No. 1
and 2), according to the following pattern.

+-----------+-----------+--+----------+----------------+
| No. 1. | Glass. |S.| Glass. | No. 2. |
+-----------+-----------+--+----------+----------------+

Take some of the glass composition, and lay it across the paper as
in the pattern, and put about a quarter of a grain of fulminating
silver in the place marked S.; and, while the glass composition is
moist, put the paper, marked No. 2, over the farthest row of glass.
Over all, paste, twice over the part that covers the silver, a piece
of paper; let it dry. By pulling both ends apart, the friction by the
glass, will cause the fulminating silver to explode.

_Detonating Girdle._ Procure a piece of girth, from 12 to 18 inches
in length. Double it, and fold it down about 1-1/2 inches, similar to
the fold of a letter, and then turn back one end of the girth, and it
will form two compartments. Then dissolve some gum arabic in water,
and thicken it by adding coarsely powdered glass. Place two upright
rows of the glass composition, in the inside of one of the folds,
about a quarter of an inch in width, and, when they are dry, sow the
first fold together on the edge, and then the second at the opposite
end; so that one end may be open. Then in the centre of the two rows,
put about a grain of fulminating silver, and paste a piece of cotton
or silk over it. Make a hole at each end of the girdle, and hang it
to a hook in the door post, and the other hook on the door; observing
to place the silk part, so that it may come against the edge of the
door upon being opened, which will occasion a report.

_Detonating Tape._ This is made of binding, about 3/8ths of an inch
in width. The same directions are to be attended to, as those we have
just given for making the girdle. It may be exploded by taking hold
of each end, and rolling the ends from each other sharply, or by two
persons pulling at opposite ends.

_Detonating Balls._ These are made in several ways, either by
enclosing a shot in paper with fulminating silver, which is exploded
by throwing it on the ground, or made of small glass globes. For the
latter, procure some small glass globes, between the size of a pea
and a small marble, in which there must be a small hole; put into it
half a grain of fulminating silver, and paste a piece of paper over
the hole. When this ball is put on the ground, and trod upon, it
will go off with a loud noise. If put under the leg of a chair, and
pressed by the weight of the body, the same effect will take place.

_Detonating Cards._ Take a piece of card, about three fourths of an
inch in breadth and 12 in length; slit it at one end, and place in
the opening a quarter of a grain of fulminating silver, close the end
down with a little paste, and when dry light the end in a candle.

Fulminating silver may be used in several other ways, affording a
variety in the effect, as the following: Fold a letter in the usual
manner, and along with the wafer introduce the fulminating silver
mixed with some glass: when the wafer is broken, in the act of
opening the letter, a violent explosion will take place.

By placing a quarter of a grain of the powder in the midst of some
tobacco in a pipe, or between the leaves of a segar, and closing the
end again to prevent the powder from falling out; it need hardly be
stated, that on lighting it, an explosion ensues. Such experiments
should be made with caution.

One-third of a grain of fulminating silver, folded in a small piece
of paper, and wrapped in another piece, then pasted round a pin,
which is to be stuck in the wick of a candle, will make a loud report.

As fulminating silver explodes by heat, or friction, it is obvious,
that various contrivances may be used for this purpose. If, for
instance, half a grain be put on a piece of _glass paper_, (paper
covered with a mixture of powdered glass and gum), then inclosed in
a piece of tin foil, and put in the bottom or side of a drawer; on
opening or shutting it, the powder will immediately explode. The same
effect takes place by putting a quarter of a grain into a piece of
paper, and placing it in the snuffers. When the candle is snuffed, it
will go off.

Two figures, one of which blows out and the other relights a candle,
are sometimes exhibited in rooms. This is performed by making two
figures of any shape or material, and inserting in the mouth of one,
a small tube, at the end of which is a piece of phosphorus, and in
the mouth of the other, a tube containing at the end a few grains of
gunpowder; observing that each be retained in the tube by a piece of
paper. If the second figure be applied to the flame of a taper, it
will extinguish it, by reason of the gunpowder, and the first will
light it again.

_Candle bombs._ These are usually called candle crackers, and are
made of glass. They are blown in small bubbles, having a neck about
half an inch long, with very slender bores, by means of which a small
quantity of water or spirit of wine is introduced. The orifice is
then closed. When they are stuck into a candle, the heat converts
the water or alcohol into vapour, which breaks the glass with a loud
report, extinguishing the flame at the same time.

_Detonations by Electricity._ The electric fluid, it is known, will
inflame combustible bodies, and, for the purpose of experiment,
several contrivances have been used. That of placing the substance,
gunpowder for instance, on a small insulated stand, and passing the
spark through it by means of conductors, will cause its inflammation.
The _electrical house_ is also an exemplification of the effect of
the electric fluid.

_Detonations by Galvanism._ Substances, placed on a glass plate,
and brought in contact with the positive and negative poles of a
galvanic battery, are readily inflamed. Hence phosphorus, gunpowder,
the metals, &c. may be inflamed in this manner. The deflagrator of
professor Hare of the University of Pennsylvania, is a powerful
apparatus for the purpose; for the construction of which, and the
details of its effects, see the American Journal of Science by
professor Silliman, of Yale College.

Among the means of producing heat that of compression is well known.
The common condensing syringe, for inflaming spunk or touch paper, is
on this principle.

This syringe is now made very portable, not more than six inches in
length and about three-eighths of an inch in diameter. The end of
the piston, which fits tight in the cylinder, has a small cavity,
in which the spunk is put, so that, when the piston is suddenly
compressed, the air is condensed, and a temperature produced,
sufficient to inflame it. The air, in the cylinder, is condensed in
the ratio of about one to forty. The calculations on the degree of
compression, which atmospheric air must undergo to produce fire by
this kind of percussion, with observations on the subject, may be
seen in M. Biot, (_Traité de Physique Experimentale, &c._ tome ii, p.
17), with other remarks concerning the sources of caloric.

To account for certain phenomena in the atmosphere, some of which are
accompanied with detonations, Mr. Nicholson (_Chemical Dictionary_,
article Air, atmospherical), conceives that the lower atmosphere
consists chiefly of oxygen and nitrogen, together with moisture, and
the occasional vapours or exhalations of bodies. The upper atmosphere
seems to be composed of a large proportion of hydrogen, a fluid of
so much less specific gravity than any other, that it must naturally
ascend to the highest place; where, being occasionally set on fire by
electricity, it appears to be the cause of the aurora borealis and
fire-balls. It may easily be understood, that this will only happen
on the confines of the respective masses of common atmospherical
air, and of the inflammable air; that the combustion will extend
progressively, though rapidly, in flashings from the place where it
commences; and that, when, by any means, a stream of inflammable air,
in its progress towards the upper atmosphere, is set on fire at one
end, its ignition may be much more rapid than what happens higher up,
where oxygen is wanting; and at the same time more definite in its
figure and progression, so as to form the appearance of a fire-ball.

Detonations frequently accompany combustion. There are many
interesting experiments on this subject, some of which we will notice
in this place, _viz._

_Experiment 1._ If a small portion of fulminating powder be placed on
a fire-shovel over a hot fire, it will become brown, then melt, and
swell up, and finally explode. See _Fulminating powder_.

_Experiment 2._ Iron filings and sulphur, made into a paste with
water, and buried in the ground for a few hours, will unite,
decompose the water, and inflame; throwing up the earth with violence
and noise. See _Artificial Volcano_.

_Experiment 3._ If nitrate of copper be spread on tin foil and
wetted, and the foil immediately wrapped up, scintillations of fire
will follow, accompanied with slight detonations.

_Experiment 4._ Five or six grains of sulphuret of antimony, with
half its weight of chlorate of potassa, when struck with a hammer
will cause a loud detonation.

_Experiment 5._ Two grains of chlorate of potassa, and one grain of
flowers of sulphur, when rubbed together, will produce a detonating
noise; and the same mixture, struck with a hammer, will give a loud
report. See _Chlorate of Potassa_.

_Experiment 6._ One grain of phosphorus and two grains of chlorate of
potassa, struck in the same manner, will produce a violent explosion.
See _Phosphorus_.

_Experiment 7._ Mix ten grains of chlorate of potassa with one grain
of phosphorus, and drop the mixture into sulphuric acid; detonation
and flame will be the consequence.

_Experiment 8._ Make a mixture of arsenic and chlorate of potassa.
On presenting a lighted match, combustion, accompanied with a
detonation, will ensue; and, if a train of gunpowder be laid, and
both inflamed at the same time, the arsenical mixture will burn with
the rapidity of lightning, while the other burns with comparative
slowness.

_Experiment 9._ If one grain of dry nitrate of bismuth be mixed with
one grain of phosphorus, and rubbed together in a metallic mortar, a
loud detonation will be produced.

_Experiment 10._ If a globule of potassium be thrown upon water, an
instantaneous explosion will be produced.

_Experiment 11._ A grain of fulminating gold, struck gently with a
hammer, will produce a loud explosion.

_Experiment 12._ A few grains of fulminating mercury, struck in the
same manner, will produce a loud detonation.

_Experiment 13._ When a grain or two of potassium are mixed with
the same quantity of sodium, no effect will take place; but if
the mixture be brought in contact with a globule of mercury, and
agitated, combustion, with a slight detonation, will follow, showing
the vivid combustion of three metals, when brought in contact with
each other.

_Experiment 14._ If to six grains of chlorate of potassa, we add
three grains of pulverized charcoal, and rub the two in a mortar,
no effect will ensue; but if we add to this mixture two grains of
sulphur, and continue the rubbing, inflammation, accompanied with a
report, will take place. See _Gunpowder of chlorate of potassa_.

_Experiment 15._ Chlorate of potassa and sulphur, rubbed in a mortar,
will produce a crackling noise, similar to that of a whip. These
reports will follow in succession as the pestle is pressed on the
mixture.

_Experiment 16._ Combustion, with a slight detonation, takes place
during the melting of coin in a nut-shell. For this purpose, make a
mixture of three parts of nitre, one part of sulphur, and one of very
fine dry saw dust; press a small portion of this powder into a walnut
shell, and put on it a small silver or copper coin, rolled up, and
fill the shell with the mixture. If the mixture be now inflamed, it
will melt the coin in a mass, while the shell will be only blackened.

_Experiment 17._ Introduce, into an inflammable air pistol, a mixture
of hydrogen gas with oxygen gas, or, in the place of the latter,
atmospheric air, and apply a lighted taper: a violent detonation will
be produced. See _Inflammable air works_.

_Experiment 18._ Mix some fine musket powder with pulverized glass,
and strike the mixture with a hammer on an anvil; the gunpowder will
explode. See _Gunpowder_.

_Experiment 19._ Take a small portion of fulminating platinum, and
place it on the end of a spatula, or on the blade of a knife, and
hold it over the flame of a candle; a sharp explosion will take
place. See _Fulminating platinum_.

_Experiment 20._ If soap bubbles be formed of a mixture of hydrogen
gas and atmospheric air, and touched with a lighted taper, they will
detonate in the air.

_Experiment 21._ If a portion of detonating oil, (_Chloride of
azote_) be heated to 212°, a violent explosion will ensue; or,

_Experiment 22._ If a portion of the same oil, of the size of a
pin-head, be brought in contact with olive oil, the effect will be
still more violent. See _Detonating oil_.

_Experiment 23._ Take ten or fifteen grains of _Higgins's_
fulminating powder, and expose it to heat on a shovel: detonation
will follow. See _Higgins's Fulminating powder_.

_Experiment 24._ If oxalate of mercury, to the amount of three or
four grains, be struck with a hammer, a detonation will ensue, in
the same manner as with the nitrous etherized oxalate of mercury, or
Howard's fulminating mercury. See _Mercury_.

_Experiment 25._ Take some of the detonating powder, prepared from
indigo, and wrap it up in paper, and strike the paper with a hammer:
an explosion will ensue. See _Detonating powder from indigo_.

_Experiment 26._ If some gunpowder be placed on the stand of an
electrical discharger, and the electric spark passed through it,
combustion, with a detonation, will be produced.

_Experiment 27._ If some gunpowder be wrapped in tin foil, and placed
on a glass plate, and the two wires of a galvanic battery brought in
contact with the foil; the foil will inflame and explode the powder.

_Experiment 28._ Mix in a mortar one part of sulphuret of potassa
with two parts of nitrate of potassa, and expose the mixture to the
action of heat in the same manner as fulminating powder: a violent
detonation will take place. The sulphuret of potassa is recommended,
in lieu of potassa and sulphur in a separate state; and although
called Bergman's fulminating powder, this compound is in fact,
according to the theory of its explosion, the same as the ordinary
fulminating powder.

_Experiment 29._ If, says Morey, (_Silliman's Journal_ ii, 21), a
given quantity of strongly compressed boiling water, be suddenly
discharged into about an equal quantity of oil or rosin, at or near
the boiling point, it will explode, to every appearance, as quickly
and violently as gunpowder.

_Experiment 30._ If zinc or iron filings, or pulverized antimony, be
mixed with chlorate of potassa, and struck with a hammer, violent
detonations will ensue. If sulphuret of iron be used, the same effect
will ensue. See MM. Fourcroy and Vauquelin's communication to the
_Société Philomatique_, in their _Transactions_.

_Experiment 31._ If oxide of mercury, obtained from its solution in
nitric acid by means of caustic potassa, be dried, and mixed with
flowers of sulphur, and struck with a hammer, a detonation will be
produced. (See _Journal de Physique_, 1779.)

_Experiment 32._ If alcohol or ether be mixed with chlorate of
potassa, into a thick paste, and the mixture struck with a hammer, an
explosion will be the consequence: or,

_Experiment 33._ If, instead of alcohol or ether, we make use of
fixed or volatile oils, and proceed in the same manner, the same
effect will ensue.

_Experiment 34._ If a small portion of chloride of azote (_Detonating
oil_) be dropped into a solution of phosphorus in ether or alcohol, a
violent explosion will take place: or,

_Experiment 35._ If in the place of phosphorized ether, other oils,
as camphorated oil, palm oil, whale oil, linseed oil, sulphuretted
oil, oil of turpentine, naphtha, &c. be brought in contact, the same
effect will ensue.

_Experiment 36._ Chloride of azote will also detonate with sundry
gaseous and solid substances, as supersulphuretted hydrogen,
sulphuretted hydrogen, phosphuretted hydrogen, nitrous gas, aqueous
ammonia, phosphuret of lime, ambergris, fused potassa, and sundry
metallic soaps. Messrs. Porret, Wilson, and Kirk, brought one hundred
and twenty-five substances in contact with it, and twenty-eight of
the number produced detonations. (_Nicholson's Journal_, vol. 34.)

_Experiment 37._ If a small quantity of ammoniacal nitrate of copper
be wrapped in paper, or in a piece of tin foil, and struck with a
hammer, a detonation will ensue.

_Experiment 38._ If a small portion of arsenic and chlorate of
potassa be mixed, and smartly struck, a flame will be produced,
accompanied with an explosion; or,

_Experiment 39._ If the same mixture be touched with a lighted match,
it will burn with considerable rapidity; or,

_Experiment 40._ If it be thrown into concentrated sulphuric acid, at
the instant of contact, a flame will rise into the air like a flash
of lightning.

_Experiment 41._ Heat a portion of deutoxide of chlorine: when the
temperature arrives at 212°, an explosion will take place, and
chlorine and oxygen be evolved.

_Experiment 42._ If prussine gas, otherwise called cyanogen, or
carburet of azote, be mixed with atmospheric air, in the proportion
of about one to four in volume, and the electric spark made to pass
through the mixture; a violent detonation will result, leaving a
mixture of carbonic acid gas and azotic gas.

_Experiment 43._ If a mixture of equal parts of nitrate of potassa,
and titanium, be thrown into a red-hot crucible, detonation will
follow.

_Experiment 44._ Melt some nitrate of potassa in a crucible, and
bring it to the state of ignition: now throw in a small quantity of
pulverized zinc, and a very violent detonation will take place.

_Experiment 45._ If one part of zinc filings and two parts of dry
arsenic acid be distilled in a retort, or exposed to heat in a
crucible, the moment it becomes red, a detonation will be produced.

_Experiment 46._ If a few drops of deutoxide of hydrogen, or the
oxygenized water of Thenard, be let fall on dry oxide of silver, a
violent action will follow, accompanied with an explosion. Several
other oxides have the same effect.

_Experiment 47._ If a portion of black wadd, an ore of manganese
found in Derbyshire, England, be brought in contact with linseed oil;
the oil will take fire, producing sometimes slight detonations.

_Experiment 48._ Take a portion of the brown oxide of tungsten,
formed by transmitting hydrogen gas over tungstic acid, in an ignited
glass tube; mix it with chlorate of potassa, and strike the mixture
with a hammer: a loud detonation will ensue; or,

_Experiment 49._ Heat some of the brown oxide in the air. It will
take fire, and burn like tinder, passing to the state of the yellow
oxide, or tungstic acid.

_Experiment 50._ If one measure of oxygen gas, and two measures of
hydrogen gas be mixed in the explosive eudiometer, and the electric
spark passed through them, a detonation will ensue, and a complete
condensation take place.

_Experiment 51._ When equal volumes of protoxide of azote, or gaseous
oxide of azote, (called also nitrous oxide), and hydrogen gas, are
treated in the same manner, the mixture will explode, leaving a
residuum, consisting of azotic gas.

_Experiment 52._ If two measures of carbonic oxide or gaseous oxide
of carbon, and one measure of oxygen, be submitted to the action of
the electric spark, a detonation will ensue, and the carbonic oxide
will be changed into carbonic acid.

_Experiment 53._ If one measure of carburetted hydrogen gas, either
the heavy or light carburetted hydrogen, called also the hydroguret
and bi-hydroguret of carbon, (the former being sometimes called
olefiant gas), be mixed with two or three measures of oxygen gas, and
the electric spark transmitted through them; a detonation will ensue,
forming water and carbonic acid.

_Experiment 54._ If one measure of cyanogen, (carburet of azote),
be mixed with two and a half measures of oxygen gas, and treated
with the electric spark, the mixed gases will explode very loudly.
The cyanogen burns, in this case, with a blue flame; although it is
usually of a purple colour. The products of combustion are carbonic
acid and azote. (See Experiment 42.)

_Experiment 55._ If one measure of arsenuretted hydrogen gas,
(obtained from an alloy of three parts of tin and one of arsenic, by
treating it with muriatic acid), and two measures of oxygen gas are
mixed together, and the electric spark is passed through the mixture;
a detonation will ensue, and water and arsenious acid be formed.

_Experiment 56._ If potassium be made to act upon a compound of
chlorine and sulphur, called chloride of sulphur, an explosion will
immediately ensue; but,

_Experiment 57._ If potassium be dropped into chlorine gas,
inflammation only will take place, accompanied with a vivid light,
forming chloride of potassium, (dry muriate of potassa.)

_Experiment 58._ If sulphuret of potassium be heated in the air, it
will burn with great brilliancy, forming sulphate of potassa; but, if
mixed with chlorate of potassa, and struck with a hammer, a violent
detonation will be produced.

_Experiment 59._ If potassium be heated in sulphuretted hydrogen
gas, it takes fire, and burns with a vivid flame, and pure hydrogen
is set free; thus proving that sulphuretted hydrogen gas, although
inflammable itself in oxygen gas, is a supporter of combustion for
potassium.

_Experiment 60._ If phosphuret of potassium be exposed to the air,
it will inflame spontaneously, forming phosphate of potassa; but if
it be dropped into water, it will produce a violent explosion, in
consequence of the immediate disengagement of phosphuretted hydrogen
gas.

_Experiment 61._ If potassium be moderately heated in the air, it
inflames, burns with a red light, and emits alkaline fumes.

_Experiment 62._ If potassium be thrown upon water, it acts with
great violence, burning with a beautiful light, of a red colour,
mixed with purple, the water becoming a solution of potassa.

_Experiment 63._ When sodium is heated strongly in oxygen or
chlorine, it burns with great brilliancy; but it does not inflame,
when thrown into water. It is converted, however, into soda. If it be
heated in oxygen gas in excess, it burns, and is converted into the
peroxide of sodium, which, when mixed with combustible bodies, and
exposed to the action of heat, deflagrates with violence, giving off
its excess of oxygen, and becoming changed into soda, or protoxide of
sodium.

_Experiment 64._ When sulphuret of sodium is mixed with chlorate
of potassa, and struck with a hammer, a detonation will ensue; and
when sodium is heated nearly to fusion, in contact with sulphuretted
hydrogen gas, it will unite with the sulphur; flame will be produced,
and hydrogen gas set at liberty. A sulphuret of sodium is thus
formed, which is usually combined with some sulphuretted hydrogen.

_Experiment 65._ When a mixture of ammoniacal gas, in a dry state,
and oxygen gas, is submitted to the influence of the electric spark,
in the explosive eudiometer, explosion will take place, and water and
azotic gas result.

_Experiment 66._ If potassium or sodium be heated in fluoric gas,
a rapid combustion takes place, in all respects as brilliant as in
oxygen gas.

_Experiment 67._ If gallic acid be placed on a red-hot iron, it burns
with flame, and emits an aromatic smell, similar to that of benzoic
acid; but, if mixed with chlorate of potassa and struck with a _hot_
hammer, a detonation will ensue. Various vegetable acids, as the
benzoic, which is highly inflammable, produce similar effects.

CHAPTER IV.

OF SCENTED FIRE-WORKS.

There is a variety of scented fires, all partaking, in a greater or
lesser degree, of a peculiar flavour, according to the substances,
which enter into their composition. It is a fact, that, in the
ordinary odoriferous fire, into which, either the so called scented
gums, or essential oils, enter as a component part, these substances
are not only decomposed in the act of combustion, but evolve,
during that process, a part of their respective _odours_, to which
we attribute the _scent_ imparted to the atmosphere. In those
instances, in which gunpowder forms a part of the composition, it
is to be remarked, that the peculiar smell of fired gunpowder is
scarcely recognized, owing to the preponderance of the scent in the
composition. Hence it is, that scented fire-works are more calculated
for confined places than for the open air.

Scented fires are various both in their nature and composition, and
may always be so modified, as, in their effect, to produce, not only
the particular flame, or appearance of the fire, but the extrication,
along with the gaseous products, of the odour of the essential oil,
or other substance made use of.

Linnæus, in a dissertation on the odours of different substances,
endeavoured to classify them. M. Lorrey (_Mémoires de la Société
Royale de Medicine_ 1784) divided them into five classes; viz.
camphors, narcotics, ethers, volatile acids, and alkalies; but it is
obvious, that it is an impossibility to class all the odours which
exist, and may be formed by the mixture, or combination of various
substances. We may consider them either pleasant, or unpleasant to
the sense of smelling. But as we recognize bodies very frequently
by their odour, with which we become familiar, as camphor and
assafœtida, for instance; so the olfactories may be affected by other
odours. Aromatic and fetid odours are opposite to each other. Some
of the gases, as the olefiant, have a fragrant smell, and others,
as hydrogen, and sulphuretted hydrogen, either alone or mixed, are
extremely unpleasant. The intestinal gas (_gas intestinaux_ of the
French) is a particular instance of the odour of a compound gas, or
mixture of gaseous fluids. The experiments of M. Jurine of Geneva,
of MM. Chevreul and Magendie, (_Ann. de Chim. et de Phys._ t. ii,
294), of M. Vauquelin, (_Journal de Pharmacie_, t. iii, p. 205),
and of MM. Lameyran and Fremy, (_Bulletin de Pharmacie_, t. 1, p.
358), are interesting on this subject. Intestinal gas differs in its
composition. It always contains carbonic acid gas, and azotic gas,
and hydrogen gas, either pure, or combined with carbon and sulphur.
Thenard (_Traité de Chimie_, iii, p. 576) contains some observations
on this subject.

In the camphor odour, Lorrey includes not only camphor itself, but
various species of laurel, myrrh, and turpentine. In the narcotic
odour, he embraces opium, various gum-resins, roses, lillies,
jessamine, &c. and musk, amber, and castor. In the ethereal odour,
different kinds of ether. Under the odour of volatile acids, he
considers that of fruits, aromatic barks, citron; and under the
alkaline odour, the acrid, and, in general, the antiscorbutic plants.
Fourcroy, in treating of the aroma of plants, or the _spiritus
rector_ of Boerhaave, (_Bulletin de la Société Philomatique_, an. 6,
p. 52,) has some interesting facts on this subject.

It is evident, that perfumes, so called, owe their peculiar fragrance
to an essential oil, which characterizes each kind; for the essential
oil obtained by distillation, partakes of the odour of the plant.
Hence the oils of mint, roses, thyme, cinnamon, cloves, &c. &c. all
of which are peculiar in this respect. Odoriferous fire-works owe
their particular properties to the presence of some gum, resin, or
oil. As to the expansibility, or rather the divisibility of odour,
several interesting facts are known. In a work, entitled _l'Existence
de Dieu, par les merveilles de la Nature_, we are informed, that,
if we take the one-fourth of a drachm of benzoin, and place it in
the four corners of a room, the odour will be recognised in an
instant. The chamber in which the experiment was made, the author
states, was 24 feet by 16, and contained 9212 cubic feet of air,
which, multiplied by 1000, would give 9216000 inches, and 1000000
parts of an inch were rendered appreciable. Therefore, he infers,
that 9216000000000 are equally perceptible in the chamber. Prevot
(_Bulletin de la Société Philomatique_, an. 6) has some observations
of the same nature, respecting camphor. If such are the effects
with benzoin, what, we may ask, would be those of the more powerful
perfumes, such as musk? One grain, or perhaps the tenth part of a
grain of musk, would scent the atmosphere of a room very perfectly.

De Laval (_Description of the Maldiva Islands_) mentions the use
of scented fire by the inhabitants, in the celebration of their
festivals. On the day of every new moon, they place at the entrance
of the churches, and the gates of their houses, cocoa shells cut in
the middle, and filled with white sand and burning coals, upon which
they burn, almost all night, sweet scented gums and woods; and at
the nocturnal festival, called _maulude_, the night on which Mahomet
died, their halls are illuminated with a multitude of lamps, and
the air is filled with the smoke of perfumes. The use of scented
fire appears to form a principal part of their devotional exercises.
Perfumes are even burnt on the graves of deceased persons.

Having mentioned the use of odoriferous plants in scented fire,
we may add, that all plants possess some peculiar character, if
aromatic, which, as one of their characters, serves to distinguish
them.

The qualities of plants are said to be similar, when they have the
same taste and odour. The odours of plants, Richard divides into
1. Fragrant, 2. Aromatic, 3. Ambrosiac, or resembling amber, 4.
Alliaceous, or resembling garlic, 5. Fetid, 6. Nauseous. The three
first are innoxious.

In the composition of scented fire-works, it is also to be observed,
that gunpowder does not always form a part; and hence their character
is various, according to the purposes they are applied to, or their
uses.

In the odoriferous water balloons, (for which, see _aquatic
fire-works_), we have, for instance, along with saltpetre and other
substances, in the different compositions, either amber and flowers
of benzoin; or frankincense, myrrh, and camphor; or amber, cedar
raspings, and the essential oils of roses and bergamot; or the
saw-dust of juniper, cypress, camphor, myrrh, dried rosemary, cortex
elaterii, and oil of roses. These are the substances, therefore,
which enter into the different compositions, in the order here given,
and which impart to the fire an odoriferous character. The relative
proportions may be learnt, by referring to the chapter on _Aquatic
fire-works_.

Scented fires are, however, little used. Their effect is nevertheless
agreeable in close rooms; but in the open air they lose this
property, or rather it is not perceptible, owing to its extreme
division.

The _vases of scent_ were greatly employed in the public feasts and
ceremonies at Rome, Athens, and, above all, in Egypt. In temples,
palaces, &c. they were mostly used. The vessels, which contained the
composition, were placed by the Athenians in sculptured or painted
vases, as well to hide their appearance, as to serve for ornament.

_Sec. I. Of Pastilles._

Pastilles, or fire crayons, are small conical troches, in the form
of a loaf, of one and a quarter inches in height, and about an inch
thick. They are made of the following composition, which is moistened
with rose-water, having some gum arabic previously dissolved in it.
The paste is made neither too thick nor too thin, but of a sufficient
consistence to work with the hand.

_Composition of Pastilles._

Storax calamite, 2 oz.
Benzoin, 2 --
Gum Juniper, 2 --
Olibanum, 1 --
Mastich, 1 --
Frankincense, 1 --
White or yellow Amber, 1 --
Camphor, 1 --
Saltpetre, 3 --
Charcoal of the linden, or willow, 4 --

The pastilles are burnt upon a plate, and communicate to the air an
agreeable odour.

_Odoriferous paste._

Gum Benzoin, ½ oz.
Storax calamite, 4 scruples.
Peruvian balsam, (dried) ¼ oz.
Cascarilla, 4 scruples.
Cloves, ½ drachm.
Charcoal, 1½ oz.
Nitre, 1 drachm.
Oil of Lemon, ½ do.
Tincture of Amber, ½ do.

The dry substances are pulverized very fine, and mixed intimately
together, and the oil of lemon and tincture of amber then added.
The whole is then made into a thick paste with common mucilage, and
formed into pieces as before mentioned. These pieces ought to be
conical. When used, they are placed on a stone, or a piece of metal,
and inflamed. This composition is said to burn with scintillations,
and to exhale a very fragrant and agreeable odour. See _Dictionnaire
de l'Industrie_.

_Perfume for Apartments._

Orrisroot, 1 oz.
Benzoin, ½ --
Charcoal, ¼ --
Ess. Bergamot, 1 drachm.

These ingredients are mixed into a paste in the usual manner,
with orange flower water, and a small quantity of gum. A small
portion, when dry, thrown on ignited coals, will exhale an agreeable
odour.--_Ibid._

M. Brillat-Savarin (_Archives des Découvertes_ iii, p. 328) has
invented a machine, which he calls the _irrorateur_, for perfuming
apartments. He objects to the ordinary mode of perfuming by fire, and
sprinkling odoriferous fluids in a room. His _irrorateur_ consists
of a small fountain, which, by compression, forces out the odour
required, and may be conveyed to any place.

_Sec. II. Of Vases of Scent._

We observed, that these vases were much in use at the public feasts
and ceremonies of the Athenians, Romans, and Egyptians.

_Composition for the Vases._

Storax, 4 oz.
Benzoin, 4 --
Frankincense, 4 --
Camphor, 2 --
Gum Juniper, 1 --
Charcoal of the willow, 1 --

These substances are pulverized, and intimately mixed, and oil of
juniper is added. The mixture is put in an earthen vessel, having a
cotton, similar to a wick, supported by means of a wire. Among the
ancients, the earthen vessels were afterwards placed in sculptured,
or otherwise ornamented vases. By using stone-ware vessels, and
mixing the composition with the spirit or oil of turpentine, the
combustion will be more rapid, and the flame more enlarged.

_Sec. III. Remarks on Spontaneous Accension._

The spontaneous accension of spirit of turpentine by the addition
of nitric acid, might furnish also a means of preparing a scented
fire extemporaneously; by putting into the vessel, previously to the
spirit of turpentine, the composition above mentioned. See _Nitric
Acid_, in the article _Nitre_.

An extemporaneous fire may also be prepared, by placing, on the
scented mixture, the following composition, namely, chlorate, or
hyperoxymuriate, of potassa and sugar, and touching the mixture
with a glass rod dipped in sulphuric acid, or oil of vitriol. The
fire will then communicate to the other materials. See _Chlorate of
Potassa_ and the article on _Pyrophori_.

Camphor, which imparts an agreeable odour, may be readily inflamed
in this manner, and the experiment even be made on snow or ice. See
_Camphor_.

_Sec. IV. Of Torches, and Odoriferous Flambeaux._

Flambeaux are usually wax torches. Odoriferous flambeaux may be
formed by melting with the wax, camphor and frankincense, and
mixing with the whole, when fluid, some of the essence of bergamot.
Although there are no directions given on that subject; yet, judging
from analogy, a mixture of that kind would be an improvement on
the flambeau, when it is to be used in rooms or for particular
occasions. They may be made either large or small, with a wick of a
proportionate size.

Torches are principally used for military purposes, to give light,
when an army is marching at night, during sieges, &c. They ought not
to be extinguished by wind or rain. The _Torches inextinguibles_, of
the French, are of this character.

Torches are made in the following manner: Take four large cotton
matches, three or four feet long; boil them in a solution of
saltpetre, and arrange them round a pine stick. Afterwards, cover
them with priming powder and sulphur, made into a thin paste
with brandy. When dry, they are to be covered with the following
composition:

_Composition for torches._

Yellow wax, 2 lbs.
White turpentine, 2 --
Sulphur 12 oz.
Camphor, 6 --
Pitch, 4 --

_Ibid._

White pitch, 32 parts.
Hard turpentine, 4 do.
Yellow wax, 32 do.
Sulphur, 12 do.
Camphor, 6 do.

_Ibid._

Black pitch, 24 parts.
White pitch, 24 do.
Turpentine, 4 do.

The second composition is that which is used in France, and,
therefore, in all likelihood, is the best formula. The flame may
be more or less scented, by using, at the same time, some of the
aromatic substances before noticed. This, however, is unnecessary for
common purposes. See _Fire-works used in war_. The flambeau, invented
by Petitpierre, (_Bulletin de la Société d'Encouragement_, No. 102),
is intended to give light to apartments.

_Sec. V. Remarks concerning Odoriferous and Fetid Fire._

Fire-works may be made extremely unpleasant to the olfactory
nerves, by mixing with their compositions, sundry substances of an
opposite quality to odoriferous oils and aromatic gums. It will be
sufficient, however, to remark, that this effect is communicated more
particularly, as in the _stink-balls_ of service, by using sulphur,
rasped horses' and asses' hoofs, burnt in the fire, assafœtida,
seraphim gum, and sundry fetid herbs or plants. The addition of the
acid of amber, called succinnic acid, and, in the shops, the _salt
of amber_, will give to the atmosphere in the vicinity of the fire,
the peculiar property of causing a continual sneezing and coughing.
Such are some of the opposite effects, which different substances
produce in conjunction with fire-works. Some of these substances,
it is obvious, would, if used in too large a proportion, retard,
if not entirely prevent the combustion; and for that reason, they
bear only a given proportion to the powder, nitre and charcoal,
which forms the basis of some, as, for instance, the _stink-ball_
composition. But in such cases, the combustion being in itself rapid,
and the degree of heat consequently proportionate, these fixed, and
otherwise incombustible bodies, in a general sense, are acted upon
by the fire, already created; and, therefore, the smoke that results
must necessarily possess, and partake of the fetid qualities of the
substances employed. On the same principle, we may account for the
effect of the scented paste, and the scented vases; but with this
difference, that many of those substances are themselves inflammable,
and, during their decomposition, emit the odour peculiar to each of
them. We know, that the elementary principles of these bodies are
carbon, hydrogen, and oxygen, variously combined, some of which are,
and some are not inflammable; and that, in combustion, when it takes
place, they are decomposed and new products necessarily ensue from a
new arrangement of the elementary principles.

It is difficult, however, to give the precise order in which
decompositions by fire result; since the substances made use of are
numerous and employed in given proportions; and since their action
upon each other, depends frequently on external agents, anomalous
circumstances, and causes which do not follow at all times the same
order of succession. Generally speaking, however, we may obtain such
a datum, all things being considered, a datum derived from the known
laws of chemical decomposition, as will furnish a _rationale_ to
explain both the cause and effect. See _General Theory of Fire-works_.

There is no doubt, that, by the action of fire on fetid, and
particularly animal, substances, as _hoofs_, &c. products may be
formed in the very act of combustion, which would increase the fetid
properties of the smoke. Zimome, obtained from the gluten of wheat by
alcohol, which takes up the gliadine, when thrown upon red-hot coals,
exhales an odour, similar to that of burning hair or hoofs, and burns
with flame. The _pyro-products_ are the immediate consequences of the
decomposition of the substance; the elements of which either separate
entirely, or recombine under some other form, as we find in the
process of destructive distillation.

Bones, and other hard parts of animals, when subjected to
distillation, furnish several products, as impure ammonia, animal
oil, and the like. Wood also, we remarked, when treating of its
carbonization for the formation of coal, produces, besides gaseous
and other volatile products, the result of its decomposition, a
quantity of acid liquor, formerly called the pyroligneous, but now
the pyroacetic acid. By separating the empyreumatic flavour, which
at first constitutes a part of the acid, the acetic acid is obtained
in a state of purity. The pyro-tartaric acid is also the result of
the action of heat; and we know, when animal substances are calcined
with potash, they produce cyanogen, the basis of the hydrocyanic and
ferrocyanic acids, the latter of which when united with the peroxide
of iron, forms the perferrocyanate of iron, commonly called Prussian
blue. Caromel also, that peculiar substance which is disengaged
from sugar and various saccharine substances, when submitted to the
action of heat, is a product, resulting from the decomposition of
the sugar. The empyreumatic, or _burnt_ flavour of certain distilled
liquors, which is corrected by redistillation with charcoal, or
passing the liquor through a filter of charcoal, is owing to the
same cause. The changes, that bodies undergo by partial roasting,
are familiar to every one; as, for instance, the torrefaction of
barley, after germination, in the preparation of malt, the degree
of which determines the colour and taste of the beer; the roasting
of rye and coffee, before they can be employed to form a beverage;
and the torrefaction of the cocoa, before it can be made into
chocolate, the sweet taste and brown colour of which are acquired in
the process, are all examples of the effect of heat on bodies. The
action of heat, according to its temperature, produces, therefore,
effects of a particular kind; and, as we regulate the heat in such
cases, we form products of different kinds. Destructive distillation,
however, would again change the character of these products. Of
this kind, we may consider the effect of the heat, produced in
the combustion of inflammable substances. In a word, the action
of heat may be so graduated, in the same manner as the tempering
of steel, as to produce only partial changes, which must ensue at
certain temperatures; or, by an increment of heat, in which a total
decomposition takes place, the effect is regulated, by the force of
affinities, exerting their influence under modified circumstances.
Hence we perceive, by reasoning _a priori_, that as substances
are altered by the action of heat, so they produce new compounds,
according to the circumstances of the action, and with or without the
agency of foreign bodies. These facts are so far applicable to the
subject under consideration, as to enable us to explain, or account
for the effects that result on the mixture, or combustion, of bodies,
a knowledge of which is undoubtedly necessary to form a theory of
fire-works in general.

CHAPTER V.

OF MATCHES, LEADERS, AND TOUCH PAPER.

We purpose, in the fourth part of our work, to go into the detail
of the manufacture of various kinds of matches, which belong more
particularly to military pyrotechny, adding, at this time, that fire
matches are differently formed, and are called the quick and slow
match. The former is commonly made of three cotton strands, drawn
into lengths, and put into a kettle, and just covered with vinegar,
(usually white wine vinegar), a quantity of saltpetre and meal powder
being added, and the whole boiled together. Some put only saltpetre
into water, and, after soaking the cotton, place it, while hot, in a
trough with some meal powder, moistened with some spirits of wine,
or brandy, which are thoroughly worked into the cotton, by rolling
it backwards, and forwards with the hands. When this is done, they
are taken out separately, and, after being drawn through meal powder,
dried upon a line. Another mode is to steep the cotton first in
vinegar, and then rub into it the following composition:

_Composition for quick-match._

Vinegar in which matches are soaked, 2 quarts.
Brandy, 1 do.
Saltpetre, ½ lb.
Priming powder, 1 do.
As much cotton as will take up all the above,
which will be about, 1 do.

To the proportions of one pound and three-quarters of cotton, one
pound of saltpetre, two quarts of spirits of wine, one pound of meal
powder, and three quarts of water, some recommend the addition of
four ounces of isinglass, dissolved in three pints of water.

Another method is to steep the matches in brandy, and then rub them
well with priming powder.

Slow match is made of hemp, or tow, spun on a wheel like cord, but
very slack, and is composed of three twists, which are afterwards
again covered with tow, so that the twists do not appear. It is
finished by boiling in the lees of old wine. This, when lighted at
the end, burns gradually, without going out.

There are several modes of preparing slow match. There is also, a
kind of slow match, which is _slower_ in carrying fire than the
preceding quick match. The quick match, for this purpose, is drawn
through the following composition, which is melted, and the operation
is continued until it attains the size of a small candle; it is then
hung up to dry.

_Composition for a slow match._

Gum mastich, 1 lb.
Saltpetre, 1 lb.
Rosin, ½ lb.
Yellow wax, ½ lb.
Charcoal, 2 oz.

When these matches are used, they are to be _lighted_, and then blown
out. If well made, they will burn a long time. They may be used for
communicating fire from one work to another. Another slow match, used
for common purposes, is made by soaking hempen cord in the following
ley:

_Lixivium for slow match._

Oak ashes, 3 lbs.
Quicklime, 1 lb.
Liquor of horse dung, 2 lbs.
Saltpetre, 1 lb.
Water, a sufficient quantity.

The cords are put into a pot, and boiled for two or three days,
renewing the lixivium from time to time, as it evaporates. They are
then taken out and dried. Good match makes a hard coal. Its duration
depends upon the quality of the materials; but, generally, four
inches will last an hour.

Further remarks on this subject, will be found in the fourth part of
this work, in which the various modern improvements are given.

The preparation of _touch paper_, for capping of serpents, crackers,
&c. may be here noticed. The directions of artists are: To dissolve
in spirits of wine, or vinegar, a little saltpetre, and immerse into
the solution, some purple or blue paper, and dry it for use. There is
no advantage gained by using either spirits of wine, or vinegar: for
the simple solution of the saltpetre in water, will be sufficient. In
the former case, it may dry sooner, but neither of these fluids can
add to the effect of the saltpetre.

In using this paper, care must be taken to prevent the paste which is
made use of, from touching any part, that is to burn. The method of
using it, is by cutting it into slips, sufficiently long to go once
round the mouth of a serpent, cracker, &c. When they are pasted on,
be careful to leave a little above the mouth of the case not pasted;
then prime with meal powder, and twist the paper to a point.

The mode of threading and joining leaders, and placing them on
different works, we shall here describe. The observations of a writer
in the _Encyclopedia Britannica_, vol. xv, p. 713, are pointed on
this subject, which we will briefly notice. Joining and placing
leaders, is a very essential part of fire-works; as it is on the
leaders that the performance of all complex works depends. The works
being prepared, and ready to be clothed, the pipes must be cut of a
sufficient length to reach from one case to the other; and then put
in the quick match, which must always be made to go in very easy.
When the match is in, cut it off within about an inch of the end of
the pipe, and let it project as much at the other end; then fasten
the pipe to the mouth of each case, with a pin, and put the loose
ends of the match into the mouths of the cases, with a little meal
powder. This being done, paste over the mouth of each case, two or
three bits of paper. This method is used for large cases.

The practice adopted for small cases, and for illuminations, is the
following: First, thread a long pipe; then lay it on the tops of the
cases, and cut a bit of the under side over the mouth of each case,
so that the match may appear, and then pin the pipe to every other
case, observing, before the pipes are put on, to put a little meal
powder in the mouth of each case. If the cases, thus clothed, are
port-fires on illuminated works, cover the mouth of each case, with
a single paper; but if they are choaked cases, situated so, that a
number of sparks from other works, may fall on them before they are
fired, secure them with three or four papers, which must be pasted on
very smooth, that there may be no creases for the sparks to lodge in,
which often set fire to the works before their time. Avoid, as much
as possible, placing the leaders too near, or one across the other,
so as to touch; as it may happen, that the flash of one will fire the
other. If the works should be so formed that the leaders must cross,
or touch, they must be made very strong, and well secured at the
joints, and at every opening.

When a great length of pipe is required, it must be made by joining
several pipes, in the following manner: Having put on one length of
match, as many pipes as it will hold, paste paper over every joint;
but, if a still greater length is required, more pipe must be joined,
by cutting about an inch off one side of each pipe near the end,
laying the quick-match together, and tying them fast with a small
twine; after which, cover the joining with pasted paper.

_Leaders_, or pipes of communication, are formed of paper, which is
cut into slips three or four inches broad, so that, when it is rolled
on the mandril or form, it may go three or four times round. When
they are very thick, they are too strong for the paper which fastens
them to the works, and will sometimes fly off without leading the
fire. The forms for these leaders are made from two to six-sixteenths
of an inch in diameter; but four-sixteenths is the size generally
made use of. The forms are made of smooth brass wire; and, when
used, they are to be rubbed over with grease, or wet with paste,
to prevent their sticking to the paper, which must be pasted all
over. In rolling of pipes, make use of a rolling board, but press
it lightly. Having rolled a pipe, draw out the form with one hand,
holding the pipe as light as possible with the other, and avoiding
any unnecessary pressure. Leaders are made of different lengths; and,
in cutting them, as is often the case, care must be taken to do it
with as little waste as possible. Leaders for marron batteries must
be made of strong cartridge paper.

The _Etoupille_ of the French is the same as the former match; it
being nothing more than a kind of quick-match, prepared by soaking
three threads of cotton in a paste, composed of the best priming
gunpowder and brandy. It is designed to communicate fire with
promptness, from one part of a fire-work to another, and, therefore,
has the same effect as the common cotton quick-match. The cotton
is usually soaked, or steeped in a paste of gunpowder and brandy,
neither too thick nor too thin, for the space of two hours, adding
more of the brandy as it evaporates. In the French preparation, gum
arabic is used, in the proportion of one ounce to a pound of powder.
In the English preparation, isinglass, or fish glue is employed, in
the proportion of four ounces dissolved in three pints of water.
Gummy and gelatinous substances are calculated for no other purpose,
than to make the powder adhere to the cotton, the quantity not being
sufficient to retard the combustion of the match. Pipes or leaders of
communication, are an essential part of fire-works, and hence great
care and attention are required in preparing them. Cotton, prepared
in the manner already described, is the substance generally made
use of. It has the property of imbibing fluids with facility; and
when spirit of wine, or brandy, or even water, is used, it absorbs,
and mechanically combines with the gunpowder, the impregnation with
which determines the quality of the match. Alcohol, deprived of as
much water as possible, or, in other words, the most concentrated,
appears to have an advantage over brandy or water. If it be used
merely as a vehicle, in order to suspend the gunpowder, and likewise
to carry it, as it were, into the fibres of the cotton, which appears
to be its _modus operandi_, then it is undoubtedly preferable to
either brandy or water. The former, as it never exceeds fourth proof,
contains always a considerable quantity of water; and, therefore, as
water decomposes gunpowder, by dissolving the nitre, and separating
the sulphur and charcoal, on which it has no effect, it is obvious,
that the gunpowder itself, when mixed with brandy, is more or less
injured. It is true, however, that the cotton in that case would
be more effectually saturated with the nitre; but it does not
follow, that it would be saturated with the gunpowder; as two of its
component parts, _viz._ the charcoal and sulphur, would be separated.
We have seen, that _touch paper_ is nothing more than paper, soaked
in a solution of, and consequently impregnated with, nitre; but, in
order to render a match more combustible, and convey fire with more
rapidity, which is required in many cases, gunpowder is the only
substance, that possesses this property in any degree.

The cotton, which is used for this purpose, is the same as that for
candle wick, and, with respect to thickness, may be from one to
six threads, according to the pipe, it is intended for. The pipe
must always be large enough for the match, so that the match may be
pushed in easily without breaking it. After it is doubled into as
many strands as required, it is usually put into a flat bottomed
copper, or earthen pan, and there boiled in a solution of saltpetre.
It is then taken out, and coiled into another pan, and the remaining
solution is poured on. Meal-powder is then put in, and pressed down,
till it is quite wet. It is then wound upon a reel, keeping the hands
moistened with the powder and fluid of the last kettle, and suffered
to remain a short time; when it is taken down, and meal-powder sifted
on both sides of it, till it appears quite dry. When dry, it is cut,
and secured in skins.

There is one advantage in this process, that the cotton in the first
place is saturated with nitre; and, in the second place, while still
wet, is combined mechanically with the meal-powder. The match I
apprehend, is in all respects equal to the _etoupille_ of the French.

The priming paste, as it is called, consisting of meal-powder and
brandy, may be preserved in close vessels for a length of time; and,
when used, may be brought to a proper degree of consistency, to be
worked, by the addition of more brandy.

The preparation of the _etoupille_, or match for communicating fire,
will be given at large, when we treat of military fire-matches. It
will be sufficient to remark, that its preparation, according to
Bigot, (_Traité d'Artifice de Guerre_, p. 74), consists in macerating
the cotton in vinegar, then pressing it, and steeping it in brandy,
and afterwards working it in a paste, composed of meal-powder, gum
arabic, camphor, and brandy, and then rolling it on a table with
meal-powder.

In preparing all kinds of matches, we may increase or lessen their
effect by increasing or diminishing the quantity of gunpowder. By
combining powder and sulphur with one or more parts of melted wax and
rosin, in the manner before mentioned, and immersing the cotton into
it, a match will be formed, which, for some purposes, is considered
preferable to the ordinary kind.

The following proportions are given for preparing 100,000 _priming
fusées_, or matches:

Cotton, 50 lbs.
Meal-powder, 30 lbs.
Vinegar, 12 galls.
Brandy, 7 galls.
Gum arabic, 2 lbs.
Camphor, 1 lb.

CHAPTER VI.

OF THE FURNITURE, OR DECORATIONS FOR FIRE-WORKS.

By the term _garniture_, used by the French, we understand the
furniture, equipage, embellishments, or decorations for sundry
fire-works, as rockets, bombs, batteries, fire-pots, &c.

_Sec. I. Of Serpents._

The directions, given for the formation of serpents, are the same in
Morel and Bigot. Paper is rolled lengthwise on a mandril, or form,
which is a quarter of an inch in diameter, of three thicknesses,
according as it is stout, and the last turn of the paper is pasted.
They are made tight and strong, and strangled first at one end. They
are then put upright in a square or round box, called a _bushel_,
for the purpose of charging them. For this end we must have a small
mallet, and a rammer of brass, of a smaller diameter than the form.
The composition is put in and rammed, proportioning the number and
force of the blows to the size of the case. The _petard_ is formed,
with extremely fine powder, then rammed, and the case choaked. To
prime them, we open the ends with a piercer, and by means of a
spatula introduce a portion of priming paste, or priming powder, in
order that the fire may communicate.

We may here remark, that large cases for serpents, as well as wheel
cases, are driven solid. There is usually a mould, in which is a
nipple, with a point at top, that serves, when the case is filling,
to stop the neck, and prevent the composition from falling out. The
air, in that event, would get into the case, and cause it to burst.
These sorts of moulds are made of any length or diameter, as the
cases are required; but the diameter of the form must be equal to
half the caliber, and the rammers solid.

_Lardons_ are of much the same nature as serpents, but are made
stronger. They are charged in the same manner. To prime them, they
are first pierced about five or six lines (or half an inch,) in
depth, which presents a greater surface to the fire, and produces,
when inflamed, more scintillations than serpents.

_Composition of ordinary serpents._

1st proportion, 2nd proportion.
Meal powder, 16 parts.
Saltpetre, 3 do. 15 parts.
Sulphur, 2 do. 4 do.
Charcoal, ½ do. 2½ do.

_Mine pots, or Serpents._

Meal powder, 1 lb.
Charcoal, 1 oz.

_Ibid._

Meal powder, 9 oz.
Charcoal, 1 --

_Serpents for Pots de Brins._

Meal powder, 1½ lbs.
Saltpetre, 12 oz.
Charcoal, 2 --

The serpents or snakes for pots of aigrettes, small mortars,
skyrockets, &c. are made from two and a half inches, to seven inches
long. Their formers are from three-sixteenths to five-eighths of an
inch in diameter; but the diameter of the cases must always be equal
to two diameters of the former. They are rolled and choaked like
other cases, and filled with composition, five-eighths of an inch
to one and a half inches high, according to the size of the mortars
or rockets, they are designed for. The remainder of the cases are
charged or _bounced_ with grained powder, and their ends pinched and
tied close. Before they are used, their mouths must be primed with
wet meal powder or priming paste as before-mentioned.

Serpents, or snakes, in fire-works, are so called from the particular
appearance, and the effect which ensues, namely, a _hissing_ and
_spitting_. This peculiar character is given by the charcoal; for,
while one part is actually consumed, in immediate contact with the
substances that enter into the composition; another part is thrown
out with violence in the state of ignition, in the form of sparks,
and receives, for the support of its combustion, the oxygen of the
air, in consequence of which carbonic acid is produced.

_Sec. II. Of Crackers._

Crackers are made in the following manner; cut some cartridge paper
into pieces, three and a half inches broad, and one foot long. One
edge of each paper fold down lengthwise, about three-quarters of an
inch broad. Then fold the double edge down one quarter of an inch,
and turn the single edge back half over the double fold. Open it,
and lay all along the channel, which is formed by the folding of the
paper, some meal powder. It must now be folded over and over till all
the paper is doubled up, rubbing it at every turn. It is now to be
bent backwards and forwards, two and a half inches or more, as often
as the paper will allow. These folds are to be held flat and close;
and, with a small pinching cord, give one turn round the middle of
the cracker, and pinch it close. Bind, as usual, with pack thread, in
the place where it was pinched. Prime one end of it, and cap it with
touch paper. When these crackers are fired, they will give a report
at every turn of the paper. If there are to be a great number of
_bounces_, the paper must be cut longer, or be joined after they are
made. If, however, they are made very long before they are pinched,
there must be a piece of wood, having a groove sufficiently deep to
let in half the cracker, which will hold it straight, while it is
pinching.

The report, produced by crackers, is on the same principle as the
report of a gun. The reports, which succeed each other, in crackers,
formed in this manner, depends, as we remarked, on the turn of the
paper, each turn producing that effect. Every part of the cracker, by
this division, represents in fact a gun; and hence, as the combustion
of one part necessarily succeeds that of another, we have, according
to the number of turns, successive explosions.

Crackers, formed in this way, may furnish a variety in exhibitions.
They may be either hung on a board, or set off on the ground. As to
the report itself, it may be increased or diminished by enlarging or
diminishing the size of each cracker, or division.

Crackers, as they are usually called, are nothing more than small
cases charged with gunpowder. The Chinese squibs are crackers of this
description. Some are four ounce cases; but the squibs, so named,
hold about half a thimble full of powder. A piece of twisted match
paper is inserted in the mouth of each of them. They are made of five
or six turns of paper, and the last one is pasted and formed of red
paper. The interior diameter is about a quarter of an inch.

_Sec. III. Of Single Reports._

Cases for reports are generally rolled on one or two ounce formers,
and seldom made larger, except on particular occasions. They are from
two to four inches in length, and are formed of thick paper. Having
rolled a case, pinch one end, quite close, and drive it down. Then
fill the case with grain powder, leaving sufficient room to pinch
at the top. Before it is pinched, a piece of paper is to be put on
the powder at the top. Reports are fired by a vent bored in the
middle, or at one end. Among the portable Chinese fire-works, reports
form usually a large number. They are closed with clay, which is
perforated to admit the match and priming.

_Sec. IV. Of Serpent Stars._

There are a variety of compositions, used to produce the appearance
of stars. Thus, there are stars of different colours, which also
produce tails of sparks, scintillations, more or less vivid, &c.
and are calculated for particular exhibitions. The serpent stars,
however, have a different object, namely, to imitate a star at first,
and afterwards a serpent.

The cases for serpent stars are choaked half an inch lower than
the common kind; and, after filling the hole with meal powder, the
following composition is put in. It is finished, but without the
operation of choaking, by adapting a piece of quickmatch, and adding
more priming powder.

_Composition for serpent stars._

Saltpetre, 16 oz.
Sulphur, 8 --
Meal powder, 4 --
Antimony, 1 --

This is the formula, given by Morel; but the formulæ of Bigot are in
some respects different, namely:

1. Saltpetre, 16 oz.
Sulphur, 8 --
Meal powder, 5 --
Antimony, 2 --
2. Saltpetre, 19¾ --
Sulphur, 8⅝ --
Antimony, 2 --
Charcoal, 0⅝ --

Serpent stars are of two kinds. The one is intended as the furniture
for rockets, &c. and the other, when moulded, to be employed in the
Roman candles.

When required to be moulded, or made into cakes, the composition
is mixed with gum and brandy, into a paste, which is spread upon a
table, having previously covered the table with meal powder. Small
cubical or other shaped pieces are cut out, sprinkled with meal
powder, and dried in the shade. The meal powder serves as a priming,
so that they may all take fire at the same time. The composition may
be formed into balls.

Serpent stars, being designed to produce a combined effect, it
appears, that, while charcoal, (and, in some instances, the sulphur,
according to the formula, but more especially the charcoal), imparts
the serpentlike appearance, the antimony, in its turn, diversifies
the flame by giving to it an asteroid character. The antimony, used
in these compositions, is not the regulus, but the crude, or common
sulphuret. Metallic antimony, however, would produce the effect in
a greater degree: but as sulphur enters into their composition, and
also into the crude antimony, there would be but little, if any,
advantage, gained in the use of the regulus.

Besides the ordinary products of the combustion of gunpowder, or
similar products, by employing nitre, charcoal, and sulphur, the
antimony, by its combustion, would be changed into an oxide, or, if
the combustion is sufficiently rapid, and the quantity of oxygen
absorbed proportionate thereto, it would form the antimonic acid.
That it is oxidized, however, and that during its oxidizement, the
appearance we have mentioned takes place, there can be no doubt.

_Sec. V. Of Whirling Serpents._

Serpents, prepared in the following manner, have a peculiar effect,
by which they are characterized. They form in the air a kind of
whirling sun; and, as they revolve by reason of their fire issuing
out at the opposite sides of their extremities, they resemble the sun
turning on its axis.

Barker's hydraulic machine, described in Gregory's Mechanics, which
is put in motion by two opposite currents of water, acting from the
two extremities of an oblong box, supported by a perpendicular hollow
shaft, through which the water first passes, acts upon the same
principle as this revolving sun. The ascension of rockets is also to
be accounted for in the same way. See _General Theory of Fire-works_.

The whirling serpents are charged entirely with composition. No grain
powder is used. A small paper stopper is rammed on the top of the
composition. Near the two chokes, but in opposite sides, the cases
are pierced with small holes, which are made to communicate with each
other, and with the composition, by means of a short leader or match.

_Sec. VI. Of Chinese Flyers._

Somewhat similar to whirling serpents are the Chinese flyers. Cases
for flyers may be made of different sizes, from one to eight ounces.
They are formed of thick paper, and are eight interior diameters
long. They are rolled in the same manner as tourbillons, with a
straight pasted edge, and pinched close at one end.

The case, being put in a mould, whose cylinder, or foot, must be flat
at top, without a nipple, is to be filled within half a diameter of
the middle. Then ram in half a diameter of clay, and, on that, as
much composition as before; and again put in half a diameter of clay.
Pinch the case then close, and drive it down flat, and afterwards
bore a hole exactly through the centre of the clay in the middle.
In opposite sides, at both ends, make a vent, and, in that side,
intended to be fired first, a small hole to the composition, near the
clay in the middle, from which carry a quickmatch, covered with a
single paper, to the vent at the other end. Then, when the charge is
burnt on one side, it will, by means of the quickmatch, communicate
to the charge on the other, which may be of a different sort.

The flyers being thus prepared, put an iron pin, that must be fixed
in the work, in which they are to be fired, and on which they are to
run, through the hole in the middle. On the end of this pin, must be
a nut to secure it. If they are required to turn back again, after
they are burnt, make both the vents at the ends in the same side,
which will alter its course the contrary way.

These flyers are intended to revolve on an axis, and to discharge at
different periods. For this purpose, a communication is made from one
vent to the other. It is evident, that the clay, which occupies the
middle of the case, is intended to prevent any communication of fire,
in the tube, from one end to the other, as this is effected on the
outside.

_Sec. VII. Of Simple Stars._

The stars, which are not made upon the former, or roller, serve to
furnish bombs and rockets. They are made in the following manner:
The composition being well mixed, and passed through a fine sieve,
is made into a paste, with gum arabic and brandy. The proportion of
the gum to the composition, is as one to sixteen. The composition is
spread equally on a table, about the thickness of a finger, and cut
into small square pieces. They are then covered with meal-powder,
which will serve for priming, and are dried in the shade.

_Composition for Simple Stars._

Saltpetre, 2 lbs.
Sulphur, 1 --
Meal-powder, ½ --
Antimony, 3/16 --

This is the general composition, however, for stars.

_Sec. VIII. Of Rolled Stars._

It will be sufficient to remark, that rolled stars are formed of the
same composition as the simple stars. The composition is mixed with
gum and brandy, formed into a paste, spread upon a table, and cut, by
a circular instrument, into pieces of the size of the Roman candle,
of which we shall speak hereafter. They are primed with the best
pistol powder, and dried in the shade. See _Roman Candle_.

_Sec. IX. Of Cracking Stars._

Cracking stars are nothing more than small marrons. They are primed,
and covered afterwards with _star-paste_, in the same manner as
meteors. They are employed as furniture for serpents and stars.
They are rolled in meal-powder, before they are used. They are the
_étoiles à pet_ of the French.

_Sec. X. Of Sundry Compositions for Stars designed for Various
Purposes._

We purpose, in this section, to present a connected view of the
different star-compositions, by merely introducing the formulæ
for their preparation. Their application will claim our attention
hereafter, when we treat of rockets and other works.

_Rocket Stars._

_White._ Meal-powder, 4 oz.
Saltpetre, 12 --
Sulphur vivum, 6 --
Oil of spike, 2 --
Camphor, 5 --
_Blue stars._ Meal-powder, 8 oz.
Saltpetre, 4 --
Sulphur, 2 --
Spirit of wine, 2 --
Oil of spike, 2 --
_Variegated._ Meal-powder, 8 drachms.
Saltpetre, 4 oz.
Sulphur vivum, 2 --
Camphor, 2 --
_Brilliant._ Saltpetre, 3½ --
Sulphur, 1½ --
Meal powder, ¾ --

Worked up with spirit of wine only.

_Common._ Saltpetre, 1 lb.
Sulphur, ¼ --
Antimony, 4¾ oz.
Isinglass, ½ --
Camphor, ½ --
Spirit of wine, ¾ --
_Tailed._ Meal-powder, 3 oz
Sulphur, 2 --
Saltpetre, 1 --
Charcoal, coarsely ground, ¾ --
_Drove._ 1. Saltpetre, 3 lbs.
Sulphur, 1 --
Brass filings, fine, ¾ --
Antimony, 3 oz.
Or 2. Saltpetre, 1 lb.
Antimony, ¼ --
Sulphur, ½ --
_Fixed pointed._ Saltpetre, 8½ oz.
Sulphur, 2 --
Antimony, 1 oz. 10 dr.
_Fine colour._ Sulphur, 1 oz.
Meal-powder, 1 --
Saltpetre, 1 --
Camphor, ½ --
Spirits of Turpentine, ½ --

_Composition of stars of different colours._

1. Meal-powder, 4 oz.
Saltpetre, 2 --
Sulphur, 2 --
Steel-filings, 1½ --
Camphor, ½ oz.
White amber, ½ --
Corrosive sublimate, ½ --
Antimony, ½ --
2. Roche-petre, 10 oz.
Sulphur, ¾ --
Charcoal, ¾ --
Antimony, ¾ --
Meal-powder, ¾ --
Camphor, ¾ --
Oil of Turpentine, sufficient to moisten them.

These compositions are made into stars, by being first worked into
a paste with brandy, in which has been dissolved some gum, usually
gum arabic, or gum tragacanth. After being rolled in powder, a hole
is made through the middle of each, and they are then strung on
quick-match, leaving about two inches between each.

3. Saltpetre, 8 oz.
Sulphur, 2 --
Amber, 1 --
Antimony, 1 --
Meal-powder, 3 --
4. Sulphur, 2½ oz.
Saltpetre, 6 --
Frankincense, 4 --
Mastich, 4 --
Corrosive sublimate, 4 --
Meal-powder, 5 --
White and yellow amber, of each, 1 --
Camphor, 1 --
Antimony and orpiment, each, ½ --
5. Saltpetre, 1 lb.
Sulphur, ½ --
Meal-powder, ½ --
Oil of petroleum, sufficient to moisten them.
6. Meal-powder, ½ lb.
Sulphur, 4 oz.
Saltpetre, 4 --
7. Saltpetre, 4 oz.
Sulphur, 2 --
Meal-powder, 1 --

The composition of stars, which carry tails of sparks, is the
following:

1. Sulphur, 6 oz.
Antimony, 2 --
Saltpetre, 4 oz
Rosin, 4 --
2. Saltpetre, rosin, and charcoal, of each, 2 oz
Sulphur, 1 --
Pitch, 1 --

These compositions are sometimes melted in a pan, and, before they
are made into stars, mixed with chopped cotton match. They may be
worked in the usual manner.

The composition for stars, which yield some sparks, is the following.
To be made into stars, it must be wetted in gum-water, and spirits of
wine, that the whole may have the consistence of a thick fluid. One
ounce of lint is put into the composition; where it remains, until it
has taken up enough to be rolled into stars.

1. Camphor, 2 oz.
Saltpetre, 1 --
Meal-powder, 1 --
2. Saltpetre, 1 oz.
Sal prunelle, ½ --
Camphor, 2 --

The composition for stars of a yellowish colour is to be
incorporated, and made into stars after the common method.

_Composition for Yellow Stars._

Gum arabic, finely pulverized, 4 oz.
Camphor, dissolved in brandy, 2 --
Saltpetre, 1 lb.
Sulphur, ½ --
Glass, in coarse powder, 4 oz.
White amber, 1½ --
Orpiment, 2 --

The composition for another kind of star, is the following:
The ingredients to be well mixed, and then rolled into stars,
proportionable to the rockets they are intended for.

Camphor, dissolved in spirit of wine by heat, 1 lb.
Gum arabic, dissolved in water, 1 --
Saltpetre, 1 --
Sulphur, 6 oz.
Meal-powder, 5 --

We will have occasion hereafter, to notice the different modes of
fixing, and arranging stars; the formation of strung stars, rolled
and drove stars, &c. Great care must be taken in making stars,
that the several ingredients are reduced to a fine powder, and the
composition is well worked and mixed. The instructions for rolling
of stars, are the following: Before we begin to roll, take a pound
of the composition, and wet it with the following liquid, sufficient
to make it stick together, and roll easy, _viz_: Spirit of wine one
quart, in which dissolve 1/4 of an ounce of isinglass. If a great
quantity of composition be wetted at once, the spirit will evaporate,
and leave it dry, before all the stars are rolled. Having rolled
one portion, shake the stars in meal-powder, and set them to dry,
which will require three or four days; but, if wanted for immediate
use, they may be dried in an earthen pan, over a slow heat, or in an
oven. It is very difficult to make the stars all of an equal size,
when the composition is taken up promiscuously with the fingers;
but, by the following method, they may be made very exact: When the
mixture is moistened properly, roll it on a flat smooth stone, and
cut it into square pieces, making each square large enough for the
stars required. There is another method used by some, which consists
in rolling the composition in long pieces, and then cutting off the
stars; so that each star will be of a cylindrical form. This method,
however, is not so good as the former; for, in order to make the
composition roll in this manner, it must be made very wet, which
makes the stars heavy, as well as weakens their effect. All stars
must be kept as much from the air as possible; otherwise they will
lose their properties.

What are called, in pyrotechny, the flaming stars, with brilliant
wheels, the moon and seven stars, the transparent stars with
illuminated rays, the transparent table star, the projected star, and
the illuminated star wheel, are all particular exhibitions, which are
produced by disposing the works in a certain form and order. They
have, therefore, no relation to those preparations, or compositions,
which produce stars. They will be considered, however, in their
respective places, when we treat of the disposition and arrangement
of fire-works.

As a general theory of stars, we may remark, that while combustion
ensues, as in other fire-works, in the manner explained in our
chapter on that subject, some substances are always employed, which
have, for their object, two effects in particular; _viz._ that of
modifying the appearance of the flame, by producing certain colours,
and increasing or diminishing the degree of combustion, and that
of throwing out, at the same time, scintillations or sparks. The
latter effect, however, is not so great in stars, as in some other
preparations, which are designed especially for the purpose. That
certain substances have a particular effect, which uniformly ensues,
under the same circumstances, is a fact obvious to all. Hence, we
see in all the numerous formulæ for stars, for those that produce
a red, a blue, a yellow, or any other flame, and those which form
tails, sparks, &c. being modified according to circumstances, that
the _effect_ is owing to the presence of one, and sometimes to the
action of two, three, and more substances, co-operating together.
That combustion may be greater or less; that it may be accelerated,
retarded, and otherwise modified; that the flame of inflammable
bodies may be varied, as to colour, by the presence of foreign
substances; that the action of one substance upon another, in certain
elevated temperatures, may produce results which would not take
place at a reduced temperature; that, for the support of combustion,
the oxygen of the nitre, or the oxygen gas of the atmosphere, may,
singly, or jointly, produce that effect, as in instances of rapid
combustion, and in the combustion of bodies actually thrown out
in the state of ignition;--these are so many considerations, all
necessary to be attended to, in establishing a theory of stars, as
well as of fire-works in general.

_Sec. XI. Of the Fire-rain, (filamentous.)_

Fire-rains are generally two inches long, and formed on a small
copper, iron, or wooden roller, two and a half lines in diameter.
Two turns of the paper are considered sufficient for them. They are
twisted at their extremities, and struck afterwards on a table, to
flatten and close them in the same manner as common cases. Using a
small funnel, they are charged with the following composition, in the
same manner as serpents. Grained powder, however, is not employed.
When charged, they are primed with paste, having also, a piece of
cotton-match attached to them.

_Composition._

Meal-powder, 16 oz.
Fine oak charcoal, 3 --

Six ounces of charcoal to a pound of powder, is the formula of Bigot.
The one given is that of Morel.

_Sec. XII. Of Sparks._

The second kind of rain-fire, called sparks, is made in the following
manner: The composition is formed into a thick liquid paste with
brandy; and eight ounces of flax are immersed in it, and kept there
for some time. The flax is then rolled into small balls, about the
size of peas. They are then rolled in dry meal-powder, and hung up in
the open air, in the shade to dry.

_Composition._

Saltpetre, 8 oz.
Meal-powder, 8 --
Camphor, 16 --
Flax, 8 --

_Sec. XIII. Of Gold Rain._

We purpose to enumerate, in the following section, all the
compositions which have been used for forming gold, as well as silver
rain. The recipe here given, it may be proper to remark, appears
to have been preferred to all others; as some French authors, and
particularly Morel, have given it a distinct place.

_Composition for Gold Rain._

Meal-powder, 8 oz.
Sulphur, 1½ --
Gum arabic, ½ --
Pulverized soot, ½ --
Lampblack, ½ --
Saltpetre, ½ --

These substances are mixed, treated, cut, and primed in the same
way as simple stars. They must be cut all of the same size. In the
furnishing of rockets and bombs, the effect they produce, is very
striking. With respect to the scintillated rain-fire, or that which
appears in sparks, the effect is owing to the flax, which, being
soaked in a mixture of meal-powder, saltpetre, camphor, and brandy,
in the same manner as before stated, produces, when inflamed, a
succession of fire, under the form we have mentioned. The camphor
seems to add to the brilliancy of the flame. There is no doubt but
a part, at least, if not the whole, is burnt, in consequence of the
oxygen of the air, the inflammation of the gunpowder bringing it
to the state of ignition. The powder itself produces at first the
combustion. The flax is, therefore, consumed, which seems to be the
last of the process, filaments, at the same time, being produced, and
the combustion accelerated by the nitre.

The fire-rain owes its effect to the charcoal, which is thrown out
in the state of ignition. In the gold fire, the effect is owing to
the presence of lampblack, soot, and nitre. There are several methods
of producing both gold and silver rains, which we will notice in the
following section.

_Sec. XIV. Of Rains in General, for Sky-Rockets, &c._

The following compositions are also used in the formation of
fire-rain;

_Gold rain_, 1. Saltpetre, 1 lb.
Meal powder, 4 oz.
Sulphur, 4 --
Brass filings, 1 --
Sawdust, 2¼ --
Pulverized glass, ¾ --
2. Meal powder, 12 oz.
Saltpetre, 2 --
Charcoal, 4 --
3. Saltpetre, 8 oz.
Sulphur, 2 --
Glass dust, 1 --
Antimony, ¾ --
Brass filings, ¼ --
Sawdust, 1½ --

_Silver-rain._ 1. Saltpetre, 4 oz.
Sulphur, 2 --
Meal-powder, 2 --
Antimony, 2 --
Sal prunelle, ½ --
2. Saltpetre, ½ lb.
Sulphur, 2 oz.
Charcoal, 4 --
3. Saltpetre, 1 lb.
Sulphur, ¼ --
Antimony, 6 oz.
4. Saltpetre, 4 oz.
Sulphur, 1 --
Powder, 2 --
Steel dust, ¾ --

_For Calibers above two-thirds of an inch._

5. Meal-powder, 16 parts.
Saltpetre, 1 ----
Sulphur, 1 ----
Steel filings, 4½ ----

_Sec. XV. Of Rain-Falls, and Stars, double and single._

The cases which contain the gold and silver rain composition, are
pinched close at one end. If they are rolled dry, four or five rounds
of paper will be sufficient; but, if they are pasted, three rounds
will be strong enough. The thin sort of cartridge paper is best for
those small cases, which, in rolling, must not have the inside edge
turned down, as in other cases, for a double edge would be too thick
for so small a caliber. The moulds for rain falls should be made of
brass, and turned very smooth in the inside; or the cases, being
very thin, would tear in coming out. The charge must be driven in
light, and the better the case fits the mould, the more driving it
will bear. These moulds have no nipple, but are made flat. It is
necessary to have a funnel made of thin tin, to fit on the top of the
case, by the help of which, they may be filled very fast. For single
rain-falls for four ounce rockets, let the diameter of the former or
roller be two-sixteenths of an inch, and the length of the case two
inches; for eight-ounce rockets, four-sixteenths, and two diameters
of the rocket long; for two-pound rockets, five-sixteenths, and three
and a half inches long; for four-pound rockets, six-sixteenths, and
four and a half inches long; and for six pounders, seven-sixteenths,
in diameter, and five inches long.

There are two kinds of double rain-falls described: some appear first
like a star, and then as rain; and some appear first as rain, and
then like a star. These different appearances may be produced in the
following manner: When stars are to be formed first, the cases must
be filled within half an inch of the top, with rain composition, and
the remainder with star composition; but when it is intended that the
rain should be first, we must drive the case half an inch with star
composition, and the rest with rain. By this method, they may make
many changes of fire; for in large rockets, they may be made to burn
first as stars, then as rain, and again as stars; or, they may first
show rain, then stars, and finish with a report. When they are thus
managed, cut open the first rammed end, after they are filled and
_bounced_, at which place they are to be primed. The star composition
for this purpose, must be a little stronger than that for rolled
stars.

_Sec. XVI. Of Substances which show in Sparks._

There are many substances, which show in sparks, when rammed in
choaked cases. The set colours are produced by regular charges. Other
charges are called compound and brilliant. Set colours, produced
by sparks, are divided into four sorts, which are denominated, the
white, black, gray, and red. The charges, to produce these several
effects, are composed of various ingredients. Thus, meal-powder and
charcoal compose the black charges; saltpetre, sulphur, and charcoal,
the white; meal powder, saltpetre, sulphur, and charcoal, the gray;
and saltpetre, charcoal, and sawdust, the red.

With respect to compound and brilliant charges, the former is
composed of many ingredients; such as meal-powder, saltpetre,
sulphur, charcoal, sawdust, sea-coal, antimony, glass-dust,
brass-dust, steel dust, cast-iron, tanner's dust, &c. or any thing
that will yield sparks; all which must be managed with discretion,
or judgment. Brilliant charges, on the contrary, are composed of
meal-powder, saltpetre, sulphur, and steel-filings, or of meal-powder
and steel-filings only, and sometimes of Chinese fire.

_Sec. XVII. Of Italian Roses, or Fixed Stars._

We prepare cases for these works, in the same manner as described in
the article respecting fixed stars. Half a spoonful of clay is put
into them, which is rammed tightly, with twelve blows of a mallet of
a moderate size. The height of the clay is then marked upon the case,
which is then charged with four spoonfuls of the composition, ramming
each spoonful with twelve blows of the mallet. These four charges
should occupy about two fingers in height. After this we add another
spoonful of earth; and divide, on the outside of the case, from the
point we marked, five equal parts. We then apply the quick-match and
paste. One end of the match is of a sufficient length, in order that
it may turn round, and come out above the other choke. We afterwards
roll the case in white paper, which must go twice round, and extend
beyond each extremity about one and a half inches. This is called the
covering. The lower end is twisted. The other end, the side of which
is twisted, resembles a goblet, and serves to inflame the rose.

The composition of the rose is given in the table for those of
revolving and fixed pieces. Their effect is, that they will produce
as many _streams_ of flames as there are holes, and consequently form
the roses or stars. The composition is six parts of powder, eight
saltpetre, five sulphur, and half a part of antimony; or two powder,
four saltpetre, and one sulphur.

_Sec. XVIII. Of Lances of Illumination, white, blue, and yellow._

We have already given the caliber, and the manner of forming the
lances. They are charged by using the funnel and rammer, in the same
manner as serpents, but without any grain-powder. They are filled
within two-twelfths of their end, and primed with the paste without
the match. The blue and yellow lances are loaded in the same manner.
The yellow are made one-third of an inch in diameter, and one inch
and a third in length; so as not to be of a longer duration in
burning than the others.

_Composition of lances._

Lances, or port-fires of illumination, may be made also without
antimony, as follows:

_Port-fire composition for Illuminations._

Saltpetre, 1 lb.
Sulphur, 6 oz.
Meal-powder, 6 oz.

The composition of the _lance à feu_ of the French, which is used
chiefly to throw occasional light across the platform, whilst
artificial fire-works are preparing, and like port-fires and matches,
to communicate fire, is given as follows: (_Œuvres Militaires_, tom
xi, p. 208.)

_Composition of the lance à feu._

Saltpetre, 3 parts.
Sulphur, 2 ----
Antimony, 2 ----

The _lance à feu puant_ is of a different kind. It is the stink-fire
lance, used for military purposes, and prepared in the same manner
as stink-pots. They are used principally in the mine, and produce
so powerful an exhalation, as to render it impossible to approach
the quarter for three or four days, and occasion also, even to the
miners, an apparent suffocation. The _lance de feu_, however, is a
different preparation from either. It is a species of squib, which is
used by the garrison of a besieged town against a scaling party. For
the preparation of _fire lances_, see the subsequent part.

_Sec. XIX. Of Slow White-flame Lances._

The composition of this lance, or port-fire, is such, that it will
burn longer than the ordinary lance. There are two formulæ given for
it. Both compositions, when driven one and a quarter inches in an
ounce case, will burn one minute, which is considered by some a much
longer time than an equal quantity of any composition, yet known,
will last.

_Composition of slow Fire._

1. Saltpetre, 2 lbs.
Sulphur, 3 lbs.
Antimony, 1 lb.
2. Saltpetre, 3½ lbs.
Sulphur, 2½ lbs.
Meal-powder, 1 lb.
Antimony, ½ lb.
Glass-dust, ¼ lb.
Brass-dust, 1 oz.

_Sec. XX. Of Lights._

We purpose hereafter to treat particularly of the Chinese lights,
Bengal lights, amber lights, blue lights, &c. We will merely mention
in this place, the composition of some of them.

_Composition for Lights._

1. Saltpetre, 3 lbs.
Sulphur, 1 lb.
Meal-powder, 1 lb.
Antimony, 10½ oz.
Oil of Spike, sufficient to mix them.

_Composition for common fire._

Saltpetre, 3 lbs.
Charcoal, 10 oz.
Sulphur, 2 oz.

_Composition for red Fire._

Meal-powder, 3 lbs.
Charcoal, 12 oz.
Sawdust, 8 oz.

_Common fire for a caliber of one-third of an inch._

Meal-powder, 16 parts.
Charcoal, pulverized, 3 ----

_Idem, for a caliber half an inch._

Meal-powder, 32 parts.
Charcoal, 7 ----

_Idem, for a caliber above half an inch._

Meal-powder, 4 parts.
Charcoal, 1 ----

_Brilliant fire for ordinary calibers._

Meal-powder, 4 parts.
Iron-filings, 1 ----

_Idem, more brilliant._

Meal-powder, 4 parts.
Steel-filings, 1 ----

_Brilliant fire for all calibers._

Meal-powder, 9 parts.
Sulphur, 1 ----
Steel, 2½ ----

_Grand brilliant fire, for calibers of three-quarters of an inch, and
upwards._

Meal powder, 16 parts.
Sulphur, 1 ----
Saltpetre, 1 ----
Steel filings, 7 ----

_Idem, clear and brilliant for any caliber._

Meal powder, 16 parts.
Saltpetre, 1 part.
Filings of the best steel, 3 ----

_Idem, large jessamine for any caliber._

Meal powder, 16 parts.
Saltpetre, 1 ----
Sulphur, 1 ----
Best steel, 6 ----

_Idem, small jessamine for any caliber._

Meal powder, 16 parts.
Saltpetre, 1 ----
Sulphur, 1 ----
Best steel, 5 ----

_White fire for any caliber._

Meal powder, 8 parts.
Saltpetre, 4 ----
Sulphur, 1 ----

TABULAR VIEW OF SOME OTHER COMPOSITIONS.

---------------------------------------------------------------------------
| PARTS OF
COMPOSITIONS. +------+------+-----+-----+-------+-----
| Meal |Salt- |Sul- |Char-|Filings|
|powder| petre| phur| coal| &c. |
-----------------------------------+------+------+-----+-----+-----+-------
White fire for any caliber, | 16 | 0 | 3 | 0 | 0 |
Blue, for parasols and cascades, | 4 | 2 | 3 | 0 3 |Zinc.
Do. for calibers, half an inch } | 4 | 8 | 4 | 0 | 17 |Zinc.
and above, } | | | | | |
Do. for any caliber, | 6 | 2 | 8 | 0 | 0 |
Sparkling, or shining fire for } | 16 | 0 | 0 | 0 | 3 |Brass.
any caliber, } | | | | | |
Green fire, for any caliber, | 16 | 0 | 0 | 0 | 3¼ |Brass.
Aurora colour, | 16 | 0 | 0 | 0 | 3 |Gold
| | | | | | powder
Chinese fire, for calibers under } | 8 | 8 | 2 | 2 | 7 |Ct.iron
an inch, } | | | | | |
Do. for calibers above an inch, | 16 | 0 | 3 | 3 | 7 |Do.
Do. for palmtrees and cascades, | 8 | 6 | 4 | 2 | 5 |Do.
Do. in white for two-thirds and } | 8 | 8 | 4 | 0 | 6 |Do.
five-sixths of an inch cal., } | | | | | |
Do. for gerbes, of ten, eleven, } | 8 | 1 | 1 | 1 | 8 |Do.
and twelve lines in diam., } | | | | | |
Bengal lights, | 0 | 32 | 9 | 0 | 5 |Ant'y.
Amber lights, | 9 | 0 | 0 | 0 | 3 |Amber.
Water squibs, | 1 | 0 | 0 | 1 | 0 |
Do. | 1 | 0 | 0 | 0½ | 0 |
-----------------------------------+------+------+-----+-----+-----+-------

_Sec. XXI. Of Lances for Petards._

Lances for petards are a kind of port-fire, used in war, but not
very often. As they will be noticed hereafter, it may be sufficient
to remark, that they are formed of cartridge paper, and the case is
strangled in the usual manner; that a small portion of bran is put
in, and then about as much good priming pistol powder in grains;
that the case is then strangled, or choaked, about two-thirds of its
length, the remaining one-third serving for a handle; and, in using
it, that the twisted end is cut off, so that the fire may communicate
to the petard.

_Sec. XXII. Of Lances of Service._

These lances serve for setting fire to works, &c. They are commonly
made fifteen inches long, upon a former or roller, one-fourth of an
inch in diameter. Four turns of the paper are sufficient for the
case. They are charged in the same way as the petard lances, and also
in the manner described for port-fires. They are primed with the
match and paste.

_Composition for the lances of service._

Saltpetre, 2 lbs.
Sulphur, 1 --
Meal powder, 5 oz.

_Sec. XXIII. Of Marrons._

Marrons are made in several ways. We shall first describe those in
cases. Formers for marrons are from three-fourths of an inch, to one
and a half in diameter. The paper for the cases must be cut twice the
diameter of the former; broad, and sufficiently long to make three
revolutions. When a case is rolled, paste down the edge, and tie one
end close; and to remove the wrinkles, and make it flat at bottom,
put in the former and drive it down. The case is then to be charged
with granulated powder, one diameter and a quarter high, and the rest
of the case, folded down tight on the powder.

The marrons being thus made, wax some strong pack-thread with
shoemaker's wax, and wind it up in a ball. Then unwind two or three
yards of it, and that part, which is near the ball, make fast to
a hook. Now take a marron, and stand as far from the hook as the
pack-thread will reach, and wind it lengthwise round it, as close as
possible, till it will hold no more in that direction; then turn it,
and wind the pack-thread on the short way; then lengthwise again,
and continue this winding until the paper is all covered. Make fast
the end of the pack-thread, and beat down both ends of the marron to
bring it in shape.

The method of firing marrons is by making a hole at one end with
an awl, and putting in a piece of quickmatch. Then take a piece of
strong paper, in which wrap the marron with two leaders, put down
to the vent, and tie the paper tight round with small twine. These
leaders are bent on each side, and their loose ends tied to other
marrons, and nailed, in the middle, to the rail of the stand.

Marron batteries are made of several stands, with a number of cross
rails for the marrons, which are regulated by leaders, by cutting
them of different lengths, and nailing them tight or loose. This
arrangement, however, is only intended for a certain purpose. For as
marrons, if well managed, will keep time to a march or a piece of
music; so, by regulating them in that way, that is to say, by cutting
the leaders of different lengths and nailing them tight or loose, we
may adjust the time of their explosion by the time of the music. In
forming batteries with marrons, the large and small kinds must be
used, and the nails for the leaders, or pipes of communication must
have flat heads. The _marrons for service_ are a different kind; they
resemble the incendiary bombs. See Fourth Part of the work.

The other kind of marron for fire-works, as described by Morel,
(_Traité Practique des Feux D'Artifice_ p. 37,) and Bigot, (_Traité
d'Artifice de Guerre_ p. 141,) are of a cubical form and of a
suitable size for the _pot_, in which it is to enter, or of any
dimensions, if it be fired alone, or without being employed as a
decoration. These cubes are filled with grain powder, and are covered
with two layers of pack-thread, which is bound very tightly, and over
this, a coat of pitch or tar. They are pierced to the powder, and a
match is adapted in the usual manner. Port-fire has been used, but is
considered to possess no advantages.

The cubical marrons are formed in the following manner: Divide a
piece of strong pasteboard in such a manner, as that each division
will form one of the sides of the cube, as represented in the
following figure.

k
+-----+
k| |k
| d |
+-----+
| c |
| |
| b |
+------+-----+------+
| c b | (A) | b c |
| | | |
+------+-----+------+
| b |
| |
| c |
+-----+

Pasteboard, formed in the above manner, it is evident, when
put together, will make a cube. (A) will be the base, and b c
respectively, will form the sides, and d the top, k k k will come
in contact with the edge of three sides. In d, (the cover), is a
hole, in order to charge it, and, if necessary, to hold the match
and priming. This, however, may be attached to either side. All the
angles are well secured with paper pasted over them. The pack-thread
must be well waxed with shoemakers' wax, before it is wound on it.

_Sec. XXIV. Of Shining Marrons._

Shining marrons are cubes of an inch at least on each surface, and
prepared in the same manner as the preceding. The excess of the
match, which is cut off in the former marron, is sufficient for these
smaller marrons. Cotton is macerated, or soaked in a paste of the
star composition, in the usual manner, viz: by mixing the composition
with brandy, and a small portion of gum, or a solution of isinglass.
The marron is then covered, about a finger in thickness, with this
cotton; or more may be used, according to circumstances. It is
afterwards rolled in meal powder, which serves for priming, and then
dried in the shade.

Shining marrons are used in furnishing bombs, fire-pots, and rockets.
They produce a brilliant effect; a vivid white light, which finishes
with a report.

_Sec. XXV. Of Saucissons._

Saucissons differ from marrons only in form. They are intended, like
them, for simple detonations. They are generally fired out of large
mortars without chambers, the same as those for aigrettes, only
somewhat stronger.

Saucissons are made of one or two-ounce cases, five or six inches
long, and choaked in the same manner as serpents. Half the number
which the mortar contains must be driven one and a half diameters
with composition, and the other half, two diameters; so that, when
fired, they may give two vollies of reports. But, if the mortars
are very strong, and will bear a sufficient charge to throw the
saucissons very high, there may be three vollies of reports,
by dividing the number of cases into three parts, and making a
difference in the height of the charge. After they are filled, pinch
and tie them at the top of the charge, almost close; only leaving a
small vent to communicate the fire to the upper part of the case,
which must be filled with grain powder very near the top. The end
then is to be pinched close and tied, and the case, bound very
tightly with waxed pack-thread, from the choak, at the top of the
composition, to the end of the case. This will strengthen the case,
and cause the report to be very loud. Saucissons should be rolled a
little thicker of paper than the common proportion. When they are
to be put in the mortar, they must be primed in their _mouths_,
and fired by a case of brilliant fire, fixed in their centre. The
charge for these mortars should be 1/6th or 1/8th more than for _pots
d'aigrettes_ of the same diameter.

For flying saucissons, the French make use of cases of three-quarters
of an inch in exterior diameter. They are charged, to the height of
half an inch, with the composition for mosaic tourbillons, which see.
They are then choaked and bound at this place, and four fingers of
grain powder are put into each, which is then covered with a stopper
of paper. They are then again choaked and bound, and the excess of
the case is cut off. They are primed with a piece of match, using the
priming paste at the same time. When the saucissons are required to
make a louder report, the part of the case, in which the powder is,
should be wrapped round with pack-thread, much in the same manner
as already described, and then covered with glue or pitch. These
saucissons are usually put in the pots of the _mosaics_, some times
in the place of them, and are arranged for exhibition on the same
frame. We may, if we wish to vary the effect, put a saucisson in one
pot, and a mosaic in another. When thrown in the air, their effect is
to occasion a report. They first, however, form a tail of fire, and
finish with an explosion. Bigot gives the difference between their
internal and external diameters at four lines, or one-third of an
inch.

Saucissons may either be used in the manner we have mentioned or
thrown by hand. According to their size, and the strength of the
case, so will be the report. They resemble a thick and short sausage,
hence their name.

_Sec. XXVI. Of Fire-Pumps._

Fire-pumps are intended for a particular use, which we will describe
hereafter. The composition is the following:

1. Saltpetre, 5 lbs.
Sulphur, 1 --
Meal powder, 1½ --
Glass-dust, 1 --
2. Saltpetre, 5 lbs. 8 oz.
Sulphur, 2 --
Meal powder, 1 -- 8 --
Glass-dust, 1 -- 8 --

Cases for fire-pumps are made like those for tourbillons, except that
they are pasted, instead of being rolled dry. In charging them, first
put in a little meal powder, and then a star; then a ladleful or
two of the above composition, which ram tightly; then a little meal
powder, on that a star, and then composition again, and so on until
the case is filled. Stars for fire-pumps should not be round; but
must be made either square, or flat and circular, with a hole through
the middle. The quantity of powder for throwing the stars must
increase as we come near the top of the case; for, if much powder be
put at the bottom, it will burst the case. The stars must differ in
size in this manner: Let the star, which is first put in, be about
one-fourth less than the caliber of the case; but let the next star
be a little larger, and the third star a little larger than the
second, and so on for the rest. Let them increase in diameter till
within two of the top of the case, which two must fit in tight. As
the loading of fire-pumps requires some skill, it will be necessary
to make two or three trials before depending on their performance.

When a number of pumps are filled, care must be taken not to put in
each an equal quantity of charge between the stars; so that, when
they are fired, they may not throw up too many stars together.
Cases for fire-pumps should be made very strong, and rolled on four
or eight-ounce formers, each ten or twelve inches long. For the
composition and preparation of stars, see _stars_.

_Sec. XXVII. Of the Volcano of Lemery._

The artificial earthquake, or volcano of Lemery, is formed by mixing
into a paste with water, about equal parts of sulphur and steel or
iron filings, and burying the mixture in the earth. The composition
in a short time, will grow hot, and burst out; the earth will break,
and open in several places.

Baumé mixed 100 pounds of iron filings and the same quantity of
sulphur together, with water, and rammed the mixture into an iron
pot. After ten hours, the mass swelled up and grew warm, aqueous
vapours arose, and the mass burst. Ten hours afterwards, the heat,
vapours, &c. greatly increased, and a flame issued forth, lasting
only from 2 to 3 minutes. Finally, the mass became red-hot, and the
burning and heat continued 40 hours longer; but without flame.

We may merely remark, that this effect is produced by the chemical
union, which takes place between the sulphur and iron, forming a
sulphuret of iron, analogous in composition to the native martial
pyrites. The water is at the same time, decomposed, during which
the mixture swells, becomes hot, and throws up the earth, producing
at the same time a large quantity of sulphuretted hydrogen gas.
This gas is formed by the combination of a part of the sulphur with
the hydrogen of the water; whilst the oxygen, the other element of
the water, goes to oxidize the metal and to acidify the remaining
sulphur. Hence sulphate of iron, or green vitriol is produced. The
experiment may be made in a common basin.

It is a remarkable fact, that spontaneous combustion, which takes
place without the application of an ignited body, ensues in a variety
of instances; and new facts daily occur, which show, that cases of
this kind are more numerous than we had reason to suspect. Besides
the old and well known effect of quicklime, pyrites, pyritous schist,
&c. in producing spontaneous combustion, it is found, that ashes and
oil, oil and cotton, and a number of substances have set fire to
cotton mills, and other works.

It is known, that, in the slaking of quicklime, a considerable degree
of heat is produced. This is owing to the solidification of the
water, or its union with the lime in the form of a hydrate, and the
consequent change, which the caloric undergoes from a latent to an
uncombined state. Hence inflammable substances, in contact with lime,
under these circumstances, are necessarily set on fire.

Spontaneous combustion arises simply from a play of chemical
affinities. The following general observations on this subject are
given by Nicholson, (_Chemical Dictionary_); and an enumeration of
the effects may lead to cautions of importance for preventing serious
accidents: "If quicklime, in any quantity, be laid in contact with
any combustible, as wood, and be wetted by accident, or to make it
into mortar, a sufficient quantity of heat may be extricated to set
fire to the wood. Animal or vegetable substances, laid together
damp in large heaps, undergo a fermentation, which often excites
combustion, as in the case of hay-ricks. Woollen cloth, not freed
from the oil used in dressing it, and laid up damp in large heaps,
has been known to take fire; and so has painted canvass. Flowers and
herbs boiled in oil, as is done by druggists, and then laid in heaps,
sometimes do the same. The mixture of linseed oil and lampblack, or
of linseed oil and black wad, is very liable to inflame. Torrefied
vegetables, as malt, coffee, or bran, put while hot, into coarse
bags, are apt to take fire. The spontaneous combustion of phosphorus,
and various pyrophori, is well known. It is suspected to be owing to
the presence of one or other of these, that charcoal sometimes takes
fire without any apparent cause; and the charcoal of peat is said to
be particularly liable to this. Hyperoxygenated muriate of potassa,
mixed with sulphur, or with sulphur and charcoal, is apt to detonate
spontaneously.

"Many cases of spontaneous combustion taking place in the human body
too are on record: and it has been observed, that all the persons,
who thus suffered, were much addicted to the use of spirituous
liquors."

_Sec. XXVIII. Of the blue and green Match, for Cyphers Devices, and
Decorations._

We had occasion to mention, that blue and green flame may be produced
by employing sundry substances, which have the property of changing
the colour of flame. This is effected in the present instance.

For the preparation of the match, we melt one pound of roll brimstone
in a glazed earthen vessel, over a slow fire, and add one ounce
of finely pulverized verdigris, and half an ounce of antimony. The
cotton for the match, may be of any length and thickness, as we
judge proper; and is to be immersed, and well soaked, in the wetted
sulphur, having previously put in the verdigris, and antimony.
Sulphur alone will form a blue light.

The matches are afterwards tied to a rod of iron, which is bent
according to the design we purpose to form, and to which they are
fastened with a very fine iron wire, called the _carcase_. They are
covered with priming paste, and a quick match is tied along the whole
length. They are then covered with bands of gray paper, and a piece
of port-fire is fixed on the end, to communicate fire.

_Sec. XXIX. Of the Purple or Violet Match._

The design is made, and the match is attached, in the same manner
as described in the last section; but without bending it. The
preparation is as follows: Make a decoction of _jujubes_, which
have been peeled, and stoned, and thicken it by adding as much of
the flour of sulphur, as will bring it to a proper consistence.
The cotton is then covered with this mixture, in the manner before
stated; its thickness to be determined, according to the time
required for it to burn. While hot, the match is primed by rolling
it in meal powder. It is then suffered to dry. The design, it is to
be observed, ought to be supported at the distance of four or five
inches from the rods which hold it, by small cross pieces of iron,
to prevent it taking fire; a circumstance necessary to be guarded
against.

_Sec. XXX. Of Meteors._

Artificial fire-works, to resemble meteors in the atmosphere, have,
if properly prepared and exhibited, a brilliant appearance. The
composition must be projected to a great height, which is either done
by rockets, or from mortars. Meteors are made in the same manner as
shining marrons, which we have already described, except, however,
that they are of a very large size and usually weigh ten pounds. The
larger they are made the better, and the more grand is their effect.
See _Shining Marrons_.

CHAPTER VII.

OF ROCKETS AND THEIR APPENDAGES.

A rocket is a flying fusée, (_Fusées Volantes_ of the French), formed
with paper, of a cylindrical shape, and filled with a composition of
certain inflammable substances, being pierced in the diameter of its
length. It is furnished with a stick, serving as a counter-weight,
or balance, to guide it vertically in its ascension. It carries
generally different garnishes, or furniture; as stars, serpents,
fire-rains, marrons, meteors &c. which are thrown off, and produce an
elegant appearance, when it terminates its flight.

Rockets have been applied to several uses. Thus, the war-rocket, as
an incendiary, improved by Congreve, and the signal rocket, are some
of its applications. These, however, are modified for the purpose,
and will be spoken of hereafter. The Indian rockets, called Fougette
(_Baguette à feu_ of the French) will also be noticed.

Although as a fire-work for exhibition, the rocket may be considered
the most grand, and, especially when furnished with various
decorations, the most brilliant, yet its utility for Military and
Naval purposes is acknowledged by all.

When treating of sundry preliminary operations in the second part of
this work, we had occasion to introduce the subject of rockets, as
respects the formation of their cases, the manner of charging and
driving them, with the tools required, and the boring of rockets,
when they have been driven solid. These subjects may be found
in sections iv, v, and viii. We purpose, however, to make such
observations as may, with the remarks heretofore offered, furnish
the reader with a general knowledge of the making, decorating, and
discharging of rockets. On the theory of the ascension of rockets,
motion of fire-wheels, &c. and observations on the rocket principle,
consult the chapter in the first part of the work, concerning the
theory of particular fire-works. For the manner of uniting sheets of
paper of several thicknesses, for cases, see _Pasteboard_.

_Sec. I. Of the Caliber and Proportion of Rockets._

Sky-rockets are generally made of seven calibers, from half an inch
to three inches. Different opinions have been entertained respecting
the proper proportions. Some contend that the height should be always
regulated by their exterior diameter. On this subject, several
experiments, it seems, have been made by an experienced artist, M.
Morel, not only to determine the length, which is best calculated to
produce the maximum of ascension, but also with respect to the length
compared with the caliber of the case.

The following tables are necessary in the formation of rockets.
The first shows the size of the caliber of the mould, for rockets
of a pound weight, and below; and the second points out the size
required for the caliber of moulds, from one pound to fifty pounds.
A lb. rocket, it must be observed, is that which is just capable of
admitting a leaden bullet of a pound weight, and so of the rest.

_TABLE_ I. _Size of the caliber of moulds of a pound weight, and
below to an ounce._

+----------+----------+
|Weight of | |
|Rockets in| Diameters|
|ounces. | in lines.|
+----------+----------+
| 16 | 19½ |
| 12 | 17 |
| 8 | 15 |
| 7 | 14¾ |
| 6 | 14¼ |
| 5 | 13 |
| 4 | 12⅓ |
| 3 | 11½ |
| 2 | 9⅙ |
| 1 | 6½ |
+----------+----------+

Here, it is evident, that the mould of a rocket of twelve ounces
in weight, ought to be seventeen lines (12 lines to the inch) in
diameter; and one of five ounces, will require a mould of thirteen
lines in diameter. Hence, we derive an easy method of finding the
size, when the weights are given: and, if the diameter of the rocket
be given, it will be equally easy to find the weight of the ball,
corresponding to the weight of that caliber.

_TABLE_ II. _Size of the caliber of moulds, of from one to fifty
pound ball._

------+---------+------+---------+------+---------+------+---------
Pounds| Caliber |Pounds| Caliber |Pounds| Caliber |Pounds| Caliber
------+---------+------+---------+------+---------+------+---------
1 | 100 | 14 | 241 | 27 | 300 | 40 | 341
2 | 126 | 15 | 247 | 28 | 304 | 41 | 344
3 | 144 | 16 | 252 | 29 | 307 | 42 | 347
4 | 158 | 17 | 257 | 30 | 310 | 43 | 350
5 | 171 | 18 | 262 | 31 | 314 | 44 | 353
6 | 181 | 19 | 267 | 32 | 317 | 45 | 355
7 | 191 | 20 | 271 | 33 | 320 | 46 | 358
8 | 200 | 21 | 275 | 34 | 323 | 47 | 361
9 | 208 | 22 | 280 | 35 | 326 | 48 | 363
10 | 215 | 23 | 284 | 36 | 330 | 49 | 366
11 | 222 | 24 | 288 | 37 | 333 | 50 | 368
12 | 228 | 25 | 292 | 38 | 336 | |
13 | 235 | 26 | 296 | 39 | 339 | |
------+---------+------+---------+------+---------+------+---------

By this second table, if the weight of the ball be given, the size
of the mould may be found: suppose it be eighteen pounds; opposite
to it is the number 262. Then we say, by the rule of proportion, (as
19-1/2, see Table 1, is supposed to be divided into a hundred parts)
100 : 19-1/2 : : 262 to the fourth term sought, viz. 51.09; which
gives for the required caliber 52 lines nearly, or four inches and
four lines. But if the caliber be given in lines, the weight of the
ball may be found: suppose the given caliber be 36 lines, then as
19-1/2 : 100 : : 36 : 184. The nearest number in the table to this is
181, which shows that the weight of the ball will be rather more than
6 lbs; or, in other words, that a rocket, the diameter or caliber of
which is thirty-six lines, is a rocket of a 6 lb. ball. See _Congreve
Rocket_.

As to moulds to prevent the rockets from splitting in the act of
charging them, Morel observes, that he has never used them. He
remarks, that a case which will not resist the force of the charge,
cannot resist the violence of the fire.

On the subject of compositions, he observes, that he has only
employed one formula, and, of course, but one standard proportion for
all sized calibers; and is of opinion, that it is useless to employ
an inferior composition, or one with which we are unacquainted, when
we have a formula, on which we may rely. This opinion, however, does
not agree with that of others.

Certain rockets, it is to be remarked, show tails of fire in
their flight, and others again do not. This depends entirely upon
the charcoal; for, if we use charcoal, made from tender and light
wood, it burns rapidly, without producing a tail of fire; but if
we use the charcoal of oak or of beech, or of other hard wood, the
rocket will form a brilliant tail of fire, during the whole period
of its ascension. It is said, however, that the charcoal of light
wood, is lighter and more inflammable, and for that reason, better
calculated for rockets; but, so far from producing the effect, we
have mentioned, a quick combustion ensues, leaving no ignited coal to
be acted upon by atmospheric air.

It is found by experiment, that even a little more or a little less
powder, gives to or takes from, the composition its effective power;
and, therefore, that the rockets, in their flight, ascend to a
greater or less height.

Some writers have asserted, that powder ought not to enter into the
composition of rockets; but in lieu thereof, only its component
parts. Where, we may inquire, is the difference? The reason, however,
assigned, is, that rockets made with gunpowder and the other
substances, will not keep any time, owing to the powder becoming
damp, and the composition spoiled. But rockets which have been made
in France and carried to the East Indies, and brought back, were
found, on trial, not to have lost any of their effect.

Different opinions have also been entertained, respecting the
composition for the charging of rockets. Some, it appears, would
employ a composition for each rocket, according to its caliber,
pre-supposing, that the inflamed matter acquired force by the
increase of its volume; without considering, that a large rocket has
more weight than a small one, and requires more power to raise it.
Experience has demonstrated, that a composition which will completely
raise a rocket of three-quarters of an inch, will raise, under the
same circumstances, a rocket of three inches; and, on the contrary,
that the last will ascend more slowly, in consequence of having to
encounter a greater resistance in the air, owing to its size.

_Sec. II. Of the Composition of Sky-rockets, and Observations on its
Preparation, and on other Subjects respecting Rockets._

The formulæ we here give, which we notice separately from the others,
are on the authority of Morel, who, by experience, has found them to
excel all others. Nevertheless, we purpose to enumerate other formulæ
for the information of the reader.

_Composition of Sky-Rockets, according to Morel._

_For Summer._ _Another._

1. Saltpetre, 17 oz. 2. Saltpetre, 16 oz.
Sulphur, 3½ -- Sulphur, 4 --
Meal-powder, 1½ -- Charcoal, 7½ --
Charcoal of oak, 8 --

_For Winter._ _Another._

3. Saltpetre, 17 oz. 4. Saltpetre, 44 oz.
Sulphur, 3 -- Sulphur, 4 --
Meal-powder, 4 -- Charcoal, 16 --
Charcoal of oak, 8 --

_Another._ _Another._

5. Saltpetre, 16 oz. 6. Sulphur, 3 oz.
Sulphur, 2 oz. 3 drachms. Saltpetre, 20 --
Charcoal, 6 oz. Charcoal, 8½ --

_Chinese Composition for rockets of honour._

Saltpetre, 5 ounces.
Sulphur, 1¼ ----
Charcoal, 2½ ----
Meal powder, 1 ----
Pulverized cast iron, 2½ ----

Two compositions for rockets of any caliber are given by Bigot; (p.
122); viz.

_Rockets of Honour._

Meal powder, 2 parts.
Saltpetre, 10 ----
Sulphur, 2½ ----
Charcoal, 5 ----
Cast iron, pulverized, 5 ----

_Particular Composition._

Saltpetre, 16 parts.
Sulphur, 4 ----
Charcoal, 9 ----
Antimony, 2 ----

In the old authors on fire-works, there are a variety of formulæ for
sky-rockets, which will be found in the following table:

------------------+------+------+------+------+------+-----------------
Kinds of Rockets.| Meal |Salt- |Char- |Steel |Sul- | REMARKS.
|powder| petre| coal | | phur |
------------------+------+------+------+------+------+-----------------
|lb.oz.|lb.oz.|lb.oz.|lb.oz.|lb.oz.|
Rockets, 4 oz. | 1 4 | 0 4 | 0 2 | 0 0 | 0 0 |
Do. 8 oz. | 1 0 | 0 4 | 0 1½| 0 0 | 0 3 |
Do. do. | 1 8 | 0 0 | 0 4½| 0 0 | 0 0 |
Do. 1 lb. | 2 0 | 0 8 | 0 2 | 0 1½| 0 4 |
Do. in general, | 0 0 | 4 0 | 1 8 | 0 0 | 1 0 |
Do. do. | 0 2 | 4 0 | 1 12 | 0 0 | 1 8 |
Do. large fly, | 1 0 | 4 0 | 0 0 | 0 0 | 1 0 |
Do. of a middling | 3 0 | 8 0 | 0 0 | 0 0 | 3 0 |
size | | | | | |
Do. do. | 1 0 | 3 0 | 1 0 | 0 0 | 2 0 |
Do. water, | 6 0 | 4 0 | 5 0 | 0 0 | 3 0 | The proportion of
| | | | | |charcoal is cer-
| | | | | |tainly too great.
Do. do. | 0 0 | 1 0 | 0 6 | 0 0 | 0 4½|
Do. do. | 0 0 | 1 0 | 0 12 | 0 0 | 0 4 |
Do. do. | 0 0 | 4 0 | 1 12 | 0 0 | 1 8 |
Do. do. | 4 0 | 4 0 | 0 0 | 0 0 | 2 0 |
Do. do. | 0 4 | 1 0 | 0 2 | 0 0 | 0 8½|
Do. do. | 1 0 | 3 0 | 0 8½| 0 0½| 1 0 | Sea-coal, 1 oz.
| | | | | |saw-dust, ¾ oz.
| | | | | |coarse char. ¼ oz.
Do. do. | 1 12 | 3 0 | 0 12 | 0 0 | 1 8 | Sawdust, 2 oz.
Do. do. sinking}| 0 8 | 0 0 | 0 12 | 0 0 | 0 0 |
charge, }| | | | | |
------------------+------+------+------+------+------+-----------------

The charcoal ought not to be pulverized very fine. It should be
passed through a coarse wire sieve, and the impalpable powder then
separated, by submitting the sifted charcoal to the same operation in
a finer sieve. The fine charcoal may be used for small fire-works.

The instructions, heretofore given, for the mixture of compositions
must be attended to; as, for instance, when we have weighed the
powder, nitre, and sulphur, the whole are to be incorporated in a
mortar, and then passed three times through a large sieve. Afterwards
add the charcoal, which is mixed thoroughly with the hand. (See the
_Mixture of Substances_, part second). With respect to the rammers,
the mode of charging, &c. see section iii, of part second.

In charging cases of half an inch caliber, fifteen blows with the
mallet must be given; for three-quarters of an inch, twenty blows;
for one inch, twenty-five blows; for one and a quarter inches,
thirty blows; one and a half inches, thirty-five blows; for two
inches, forty blows; and for three inches, fifty blows;--that is to
say, the number of blows must be given to each charge put in, which
ought to occupy half the interior diameter of the case. The rammer
must be frequently taken out, and struck, so as to disengage any of
the composition, which may adhere to it. Respecting the accuracy of
the charge, see _Table rocket_, in the chapter on _Table fire-works_.

The garnishing, or furniture, should not exceed, in any case,
one-third the weight of the rocket. The head is made of pasteboard,
first moistened, and then rolled round a conical former. It must
enter the mould, and, when inserted, ought to be pasted round the
juncture with paper. (See sec. iii, and iv.)

With respect to rocket sticks, as they are used for counter-weights,
Morel remarks, that, for rockets up to an inch and a quarter, they
may be formed of the branches of light wood, as hazle, elder, &c. and
for rockets above that caliber, heavy wood, but perfectly straight
and without knots, may be used. As a general rule, the sticks are
made ten or twelve times the length of the rocket, and in thickness
about one-third of the exterior diameter of the case. In the large
end of the stick, there is a gutter or groove, formed to receive the
rocket. When branches are used, they must also lie straight, and
cut flat at the large end, about half their thickness, so that they
may be joined to the rockets with a pack-thread, or fine iron wire.
If the stick is too weighty, it may be shaved off the whole length.
Rockets, we may remark, that are not well balanced by the stick, will
not ascend regularly. If the stick be too light, they will rise in
a zigzag direction; but, if too heavy, their accelerated force will
be diminished, their motion slow, and, when they arrive at a certain
height, they will fall in a semicircular position. (See section v, of
this chapter, _on the Dimensions and Poise of rocket sticks_.)

We may further remark, that all rockets are formed and proportioned
by the diameter of their orifice. When the height is six and
two-thirds diameter, the foot should be one diameter and two-thirds.
The choak of the mould, if used, is one diameter and one-third in
height, which must be made out of the same piece as the foot, and fit
tight in the mould. There must be an iron pin to keep the foot fast.
The nipple is half a diameter high, and two-thirds thick, and made of
the same metal as the piercer. The height of the piercer is three and
a half diameters, and at the bottom one-third of a diameter thick,
and from thence tapering to one-sixth of a diameter. The best mode of
fixing the piercer in the cylinder, is to make that part below the
nipple sufficiently long to go entirely through the foot, and rivet
at the bottom. The former or roller, for the cases, is seven and a
half diameters from the handle, and its diameter is two-thirds of
the bore. The end of the former is one diameter and two-thirds long,
and of the thickness given above. The small part, which fits in the
hole in the end of the roller, when the case is pinched, is one-sixth
and one-fourth of the diameter of the mould thick. The first drift,
or rammer, must be six diameters from the handle; and this, as well
as all other rammers, must be a little thinner than the former, to
prevent the sacking of the paper, when the charge is driven. In the
end of this rammer must be a hole to fit over the piercer. Several
hollow rammers are used in completing the charge. (See our remarks in
part second on _Charging of cases_.)

The diameter of the nipple should always be equal to that of the
former. With regard to the thickness of moulds, it is immaterial,
provided they are substantial and strong. Solid driving is more
expeditious than charging over a piercer; but great labour and
attention is required in boring them, an account of which, with the
apparatus required, may be seen in _Part second_.

The following table of the dimensions of rocket-moulds, if the
rockets are rammed solid, may be useful.

-----------+---------------+-----------------+--------------
|Length of their| |
Weight of |moulds without |Internal diameter|Height of the
rockets. |their feet. | of the moulds. | nipples.
-----------+---------------+-----------------+--------------
lbs. oz. | Inches. | Inches. | Inches.
-----------+---------------+-----------------+--------------
6 0 | 34.7 | 3.5 | 1.5
4 0 | 38.6 | 2.9 | 1.4
2 0 | 13.35 | 2.1 | 1.0
1 0 | 12.25 | 1.7 | 0.85
0 8 | 10.125 | 1.333 &c. | 0.6
0 4 | 7.75 | 1.125 | 0.5
0 2 | 6.2 | 0.9 | 0.45
0 1 | 4.9 | 0.7 | 0.35
0 0½ | 3.9 | 0.55 | 0.25
6 drachms.| 3.5 | 0.5 | 0.225
4 drachms.| 2.1 | 0.3 | 0.2
-----------+---------------+-----------------+--------------

_Sec. III. Of the Heading of Rockets._

The heads for sky-rockets must always bear a given proportion to the
rockets.

A pointed cap, adapted to the summit, will make a rocket ascend to a
greater height, as it serves to facilitate its passage through the
air. To these rockets may be added several other things; as a petard,
which is a box of tin plate, filled with fine gunpowder, placed on
the summit. The petard is put on the composition, at the end, when
it has been filled, and the remaining paper of the cartridge is
folded down over it, to keep it firm. The petard produces its effect,
when the rocket is in the air, and the composition is consumed. We
have already remarked, that the upper parts of rockets, that is to
say, their _heads_, are generally furnished with some composition,
which takes fire, when it has reached its greatest height, emits a
considerable blaze, or produces a loud report and whizzing noise. Of
this kind are saucissons, marrons, stars, showers of fire, &c. The
heads of sky-rockets, are, therefore, furnished with a variety of
compositions.

When a rocket is five diameters, and one-sixth in length, the case
being cut to this length, after it is filled, the head should be
two diameters high, and one diameter 1/6th, and 1/2 in breadth.
The perpendicular height of the cone, or cap of the head, must be
in diameter, one, and one-third. There is a circular collar, to
which the head is fixed, turned out of any light wood; its exterior
diameter must be equal to the interior diameter of the head.
One-sixth is sufficient for its thickness, and round the outside must
be a groove. The interior diameter of the collar should not be quite
so wide as the exterior diameter of the rocket. When it is to be
glued on the rocket, two or three rounds of paper are to be cut off,
which will make a shoulder for it to rest upon. Two or three rounds
of paper well pasted, will be sufficient for the head. Put the collar
on the mandril, or former, which must fit the inside of the cone when
formed; then, with a pinching cord, pinch the bottom of the head into
the groove, and tie it with small twine. To make the caps, cut the
paper in round pieces, equal in diameter to twice the length of the
cone, which is to be made. These pieces, being cut into halves, will
make two caps each. Paste over the caps a thin white paper, which
must be a little longer than the cone, so as to project about half
an inch below the bottom: this projection of paper being matched and
pasted, serves to fasten the cap to the head, A conical former is
used to shape the head.

_Sec. IV. Of the Decorations for Rockets, and the Manner of filling
their Heads._

Having, in the preceding section, shown the mode of forming heads, or
conical caps, for rockets, we may now remark, that the furniture or
decorations for rockets consist of stars of different kinds, such as
tailed, brilliant, white, blue, yellow, &c. or gold and silver rain;
or serpents, crackers, fire-scrolls, or shining marrons, or small
rockets; the kind of the decoration depending entirely upon taste and
fancy.

In loading the heads of rockets, a ladleful of powder must be put
into each head, along with the decorations. This is absolutely
necessary in order to burst the head and disperse the stars, &c.

Various experiments have been instituted, to make rockets, by
employing sundry compositions for charging the cases, along with
the rocket composition, to produce, like the heads of rockets, when
they burst, different appearances. M. Morel informs us, that he made
several experiments with that view, but did not succeed. He ascribes
the failure to several causes; and, in substance, concludes, that
such figures have a greater weight than rockets are able to carry;
that their irregular forms and movements produce, in the ascension,
a contrariety of effects, which impedes their flight; and that,
if they were to succeed, the rapidity, with which the fuse passes
through the air, would prevent any thing being distinguished. As
such exhibitions are shown with effect, by the bursting of the head
of the rocket, after it has ceased to burn; we are of opinion,
that the only mode, which can be adopted, with success, is the one
already described. For after the rocket has ceased, or finished, the
last portion of fire is communicated to the head, containing the
decorations, which is blown off, and its contents are inflamed and
dispersed. It is true, however, that, in some compositions, stars,
previously made, and therefore not mixed with the composition, are
put in the cases along with the charge: We have an instance of this
in the fire-pump, Roman candle, &c. The cases for these are filled in
the following order: first with gunpowder to a certain extent, then a
star, then composition; then powder again, then another star, and so
on alternately, until the charge is completed; but, in this instance,
the star, as well as the gunpowder, is distinct from the composition,
which forms the fire-pump. For, while the composition performs
one part, the gunpowder acts another, by throwing the stars out,
which, by their combustion, give the appearance they are intended
to produce. Stars may be formed, or rather exhibited, in this way,
which, in fact is much after the manner, in which they are used for
the heads of rockets. But the experiments of Morel appear to have
been made, with a view to produce that effect from the rocket itself,
and altogether by the composition, by varying or otherwise modifying
it. Star-composition, it must be observed, is of a greater specific
gravity than any ordinary composition, in consequence of the weight,
and quantity of metallic and other substances, which enter into it.
By arranging stars in cases, in the mode described for the fire-pump,
the effect, we have spoken of, always takes place. In rockets,
however, which require to be driven with considerable force, and over
a piercer, they could not be used.

_Sec. V. Of the Dimensions and Poise of Rocket-sticks._

Although we have made some observations on the size, as well as the
use of rocket-sticks, in a general way; yet the subject being very
important, as rockets, however well made, cannot take a vertical
direction without them, we subjoin the following table, which
exhibits, at one view, the length, &c. of the stick, compared with
the weight of the rocket, and the poise it must necessarily have
from the point of the cone. The _centre_ of gravity is a necessary
consideration.

---------+------------+-----------+---------+-----------+-------------
Weight | | | | | Poise from
of the | Length of | Thickness | Breadth | Square at | the point of
rocket. | the stick. | at top. | at top. | bottom. | the cone.
---------+------------+-----------+---------+-----------+-------------
lbs. oz. | Ft. In. | Inches. | Inches. | Inches. | Ft. In.
---------+------------+-----------+---------+-----------+-------------
6 0 | 14 0 | 1.5 | 1.85 | 0.75 | 4 1.5
4 0 | 12 10 | 1.25 | 1.40 | 0.625 | 3 9.
2 0 | 9 4 | 1.125 | 1. | 0.525 | 2 9.
1 0 | 8 2 | 0.725 | 0.80 | 0.375 | 2 1.
0 8 | 6 6 | 0.5 | 0.70 | 0.25 | 1 10.5
0 4 | 5 3 | 0.3750 | 0.55 | 0.35 | 1 8.5
0 2 | 4 1 | 0.3 | 0.45 | 0.15 | 1 3.
3 1 | 2 6 | 0.25 | 0.35 | 0.10 | 11 0.
0 0½ | 2 4 | 0.125 | 0.20 | 0.16 | 8 0.
0 0¼ | 1 10½ | 0.1 | 0.15 | 0.5 | 5 0.5
---------+------------+-----------+---------+-----------+-------------

** Transcriber Note: the last three rows of this table have many
typos. The rows were probably intended to be as follows:

0 1 | 2 6 | 0.25 | 0.35 | 0.10 | 1 1.
0 0½ | 2 4 | 0.125 | 0.20 | 0.16 | 0 8.
0 0¼ | 1 10½ | 0.1 | 0.15 | 0.5 | 0 5.5
---------+------------+-----------+---------+-----------+-------------
** end of Transcribers Note **

The last column expresses the distance from the top of the cone,
where the stick, when tied on, should balance the rocket, so as to
stand in equilibrium on the edge of a knife.

Having given the method of preparing sticks, nothing more is
necessary on that head, except that they should be cut and planed
according to the dimensions in the table. A groove must be made the
length of the rocket, and as broad as the stick will allow. Two
notches may be cut on the opposite flat side, for the cord which ties
on the rocket. The top of the stick should always touch the head. In
fixing on the stick, care must be taken to secure it well.

It is the stick which gives a proper counterpoise, without which the
rockets would not ascend; and, unless they were of a proper length
and weight, instead of taking a vertical or perpendicular direction,
they would describe a parabola, or take an oblique course, and fall
to the ground.

A rocket stick may be made for any sized rocket, although not
expressed in the table, by assuming the data there given, taking care
to find the centre of gravity. For the sticks for war-rockets, see
_Congreve Rocket_.

_Sec. VI. Of the Mode of Discharging Rockets._

Having completely prepared the rockets with all their appendages,
we consider in the next place the manner of discharging them; in
performing which some care is to be observed. The old and heretofore
common manner, of setting them off by hanging them on nails and
hooks, has many objections. The best mode is to have a ring made
of strong iron wire, large enough for the stick to go in, as far
as the mouth of the rockets. Then let this ring be supported by a
small iron, at some distance from the post or stand, to which it is
fixed; and have another ring fixed in the same manner, to receive and
guide the small end of the stick. Rockets, thus suspended, will have
nothing to obstruct their flight. The upright, to which the rings are
fixed by the small iron, must be exactly vertical.

Two, three, or more sky-rockets may be fixed on one stick, and fired
together. Their appearance, in this case, is very striking. Their
tails will seem but as one of immense size, and the discharge from
so many heads, at the same time, will resemble more the effect of
an air balloon. Rockets, for this purpose, must be made alike in
every particular. If the rockets are half-pounders, whose sticks are
six and a half feet long, then two, or three, or six of these are
to be fixed to one stick, the length of which must be nine feet and
three-quarters. Cut the top of it into as many sides as there are
rockets, and let the length of each side be equal to the length of
one of the rockets without its head; and in each of these sides, let
a groove be made. From this groove, plane it round, down to the end.
The rule is, that the stick at top must be sufficiently thick, when
the grooves are cut, for all the rockets to lie as near as possible,
without pressing each other. When only two rockets are to be fixed on
one stick, let the length of the stick be the last given proportion,
but shaped after the common method, and the breadth and thickness,
double the usual dimensions.

When several rockets are placed upon one stick, there will be some
danger of their flying up without the stick. Cases, when tied on all
sides of the stick, cannot be secured to it by rope passing over
notches as before mentioned. Instead of which, drive a small nail in
each side of the stick, between the necks of the cases; and let the
cord, which goes round their necks, be brought close under the nails.
A quick match, without a pipe, is to be fixed to the mouth of one
rocket, and carried to another. This match will communicate fire at
one and the same time.

There is a mode of discharging sky-rockets without sticks, which
consists in using balls of lead tied to a wire two or three feet
long, and fixing the other end of the wire to the neck of the
rocket. These balls answer the purpose of sticks, when made of a
proper weight, which is about 2/3ds the weight of the rocket. They
will balance the rocket at the usual point. To fire rockets, thus
equipped, a different mode must be adopted. They are hung, one at
a time, between the tops of wires placed for that purpose, letting
their heads rest on the wire, and the balls hang down between them.
The wires are about three feet long, and inserted in a circle, in
a block of wood, which must lie level, and the wires perfectly
vertical. The diameter of the circle is two and a half inches; it is
divided into three equal parts, and at each one is a rod or wire.

We may introduce here a description of the _stands for sky-rockets_,
and the _girandole chests for the flights of rockets_. The first is
formed of two rails of wood, of any length, supported at each end by
a perpendicular leg, so that the rails lie horizontal; and let the
distance from one to the other be almost equal to the length of the
sticks of the rockets, intended to be fired. Then in the front of the
top rail, drive square hooks at eight inches distance, with their
points turning sidewise; so that, when the rockets are hung on them,
the points will be below the sticks, and keep them from falling or
being blown off by the wind. At the front of the rail at the bottom
must be staples, driven perpendicularly under the hooks at top.
Through these staples put the small ends of the rocket-sticks. They
are fired by applying a lighted port-fire to their mouths. Two or
three seconds will expire before they ascend.

_The girandole chest_ is composed of four sides of equal dimensions;
but may be made of any size, according to the number of rockets to be
fired. Its height must be in proportion to the rockets, and higher
than the rockets with their sticks. When the sides are joined, fix in
the top, as far down the chest as the length of one of the rockets
with its cap on. On this top, make as many square or round holes, to
receive the rocket-sticks, as the number of rockets to be fired; but
let the distance between them be sufficient to prevent their touching
each other. From one hole to another cut a groove of a sufficient
size for a quick match to lie in. The top being thus fixed, put
in the bottom, at about 1-1/2 feet distance from the feet of the
chest. In this bottom, make as many holes as at the top, and all to
correspond, but not so large as those in the top.

To prepare the chest, a quick match is laid in all the grooves,
from hole to hole. Then take the sky-rockets, and prime them with
meal-powder, or priming paste, as before-mentioned, and put a bit of
match up the cavity of each, which should project out. Put the sticks
of the rockets through the holes in the top and bottom of the chest,
so that their mouths may rest on the quick match in the grooves. The
rockets will then be fired at once. There should be a door in the
side of the chest, and also a cover, to secure the rockets until they
are required.

The _fountain of rockets_, an exhibition which frequently accompanies
a display of works, is nothing more than a number of rockets
discharged at the same time.

There are some improvements on the girandole chest, and on the
different modes of discharging a series of rockets.

We may mention one contrivance for this purpose, as described by
Morel. It is an oblong box furnished with a double lid, which, when
shut, resembles the roof of a house. This box is sixty inches in
length, ten inches in breadth, and nine inches in height. It rests
upon a frame, and has a bottom in which are one-hundred holes, to
receive the same number of rocket-sticks, the rockets resting on the
bottom of the box. The lid serves to prevent the access of moisture,
and to secure the rockets. No part of the rocket is seen in the
box. They are set off by first strewing meal-powder on the bottom,
which is then in contact with their mouths, and applying a lighted
port-fire. They rise out of the box all together, and at the same
time. When fired together, so as to form a _flight_ of rockets, the
French use them of three-quarters of an inch caliber.

The _girandole_ may be considered an assemblage of a large number
of rockets of various calibers, arranged in gradation; the largest,
occupying the first range, &c. The girandole constitutes, as a
fire-work, in the language of Morel, the _feux de gouvernement_.

Similar to this is a contrivance for the same purpose, but not so
extensive, and rather differently formed. It consists of a case, in
which there are holes to receive the sticks and support the rockets.
The case is supported by legs; two of which, working upon a joint,
may be extended, and thus the rockets be made to move in any angular
direction. The inclination given is hardly ever more than 55 degrees.
The legs are pointed, so as to retain their position. If the rockets
are to ascend vertically, the two legs, which move in a joint, are
closed. They are stuck in the ground at the same place.

For the mode of discharging the _Congreve Rocket_, see the article on
_Congreve Rockets_.

_Sec. VII. Of the Appendages, and Combinations of Rockets._

We purpose to notice, in this section, some of the modes of
arranging, combining, and also of varying the effects of rockets.

When a sky-rocket is fixed with its stick on the top of another, a
fresh tail of fire will be observable, when the second rocket takes
fire, which will mount to a great height. The preparation of these
rockets consists in filling a two pounder only half a diameter above
the piercer, (which must be observed in this instance,) and its head
with not more than ten or twelve stars; adapting a stick as usual,
which must be made a little thicker than customary. This stick must
be cut in half the way flat, and in each half a groove, so that,
when joined together, they will receive, and be large enough to hold
the stick of a half pound rocket. The heading is then performed as
before described. The stick of this small rocket is to be fixed in
the hollow of the large one, so far that the mouth of the rocket may
rest on the head of the two pounder; and, from the head of the two
pounder, a leader is to be carried into the mouth of the small rocket.

When sky-rockets are fixed one on the top of another, they are called
_towering rockets_, on account of the great height to which they
ascend. They are made in the following manner: Fix on a pound rocket,
a head without a collar; then take a four-ounce rocket, which may
be headed or bounced, and rub the mouth of it with priming paste,
or meal-powder and spirits of wine. Put it into the head of a large
rocket with its mouth downwards, previously, however, inserting a bit
of quick match in the hole made through the clay of the pound-rocket,
which match should be of a sufficient length to go a small distance
up the bore of the small rocket, to fire it when the large one is
burnt out. The four-ounce rocket being too small to fill the head of
the other, roll round it as much tow as will make it stand upright in
the centre of the head. Then paste a single paper round the opening
of the top of the head of the large rocket. The large rocket must
have only half a diameter of charge rammed above the piercer; for,
if filled to the usual height, it would turn before the small one
takes fire, and entirely destroy the intended effect. When one rocket
is headed with another, there will be no occasion for any _blowing
powder_; for the force with which it flies off will be sufficient
to disengage it from the head of the first fired rocket. The sticks
for these rockets must be a little longer than for those headed with
stars, rain, &c.

The _caduceus rockets_ are formed of two rockets. When attached,
one on each side at the top of the stick, they form a right angle,
their mouths being equidistant from the stick. The sticks, for this
purpose, must have all their sides alike, which should be equal to
the breadth of a stick, proper for a sky-rocket of the same weight
as those intended to be used, and to taper downwards as usual. They
must be long enough to balance them, and one length of a rocket from
the cross-stick. The cross-stick is that to which the cases are tied,
and serves to preserve them steady in that position. Each rocket,
when tied on, should form either an angle of 45, or 60 degrees with
the large stick, or both together an angle of 90 or 120 degrees.
The last, however, is considered a preferable angle. When tying on
the rockets, attention ought to be paid to place their heads on the
opposite sides of the cross-stick, and their ends on the opposite
sides of the long stick. Quick-match is then to be carried from the
mouth of one into that of the other. When these rockets are to be
fired, suspend them between two hooks or nails, and apply fire to the
leader in the middle, and both will take fire at the same time.

The particular effect of this rocket is, that, in rising, it forms
two spiral lines, or double worms, in consequence of their oblique
position; and the counterpoise in the middle (the stick) causes them
to ascend vertically. Rockets, for this purpose, must have their
ends choaked close, without either head or bounce; for a weight at
top would be an obstruction to their mounting. They do not rise so
high as single rockets, because of their serpentine motion, and the
resistance they meet with in passing through the air. This resistance
is greater than two rockets of the same size fired singly.

_Honorary rockets_ are nothing more than sky-rockets, except that
they carry neither head nor report. They are closed at top, to which
is attached a cone. On the case, close to the top of the stick, a
two-ounce case is tied. This last is filled with a strong charge, and
is usually about five or six inches in length, and pinched close at
both ends. At the opposite sides, at each end, a hole must be bored,
in the same manner as in tourbillons; and from each hole, a leader
must be carried into the top of the rocket. When the rocket is fired,
and has arrived at its proper height, it will communicate fire to the
case at the top, which will cause the rocket and stick to descend
very fast to the ground, and, in its descent, will represent a worm
of fire.

There are several modes of placing the small case, so as to produce
the best effect. One is by letting the stick rise a little above the
top of the rocket, and tying the case to it, so as to rest on the
rocket. These rockets are not furnished with cones. Another method is
also recommended; namely, in the top of the rocket, fix a piece of
wood, in which drive a small iron spindle; then make a hole in the
middle of the small case, through which put the spindle, and fix, on
the top of it, a nut, to keep the case from falling off. The case,
by this means, will turn very fast, without the rocket. This method,
however, is not preferred.

One-pound rockets are considered the best size for this purpose.

_Chained rockets_, as they are sometimes called, are another
modification of the manner of fixing rockets; for the intention is
to make several sky-rockets rise in the same direction, and equally
distant from each other. This effect is produced in the following
manner: Take six, or any number of sky-rockets, of any size; then cut
some strong pack-thread into pieces of three or four yards long, and
tie each end of these pieces to a rocket in this way;--after tying
one end of the pack-thread round the body of one rocket, and the
other end to another, take a second piece of pack-thread, and make
one end of it fast to one of the rockets already tied, and the other
end to a third rocket; so that all the rockets, except the outside,
will be fastened to two pieces of pack thread. The length of thread,
from one rocket to the other, is indeterminate. They must all be of a
size, and their heads filled with the same weight of stars, or other
decorations.

In the mouth of each rocket, a leader is to be fixed of the same
length, and when fixed, they may be hung almost close. Tie the ends
of the leaders together, and prime them: When this is fixed, all
the rockets will mount at the same time, and separate as far as the
strings will admit. They will preserve the same order and distance,
if they are rammed alike, and equally well made.

The manner of dividing the tail of a sky-rocket, so as to form an
arch when ascending, is thus performed. Having some rockets made, and
headed according to fancy, and tied on their sticks, get some sheet
tin, and cut it into round pieces of about three or four inches in
diameter. Then, on the stick of each rocket, under the mouth of the
case, fix one of these pieces of tin, sixteen inches from the head of
the rocket, and support it by a wooden bracket as strong as possible.
The use of this is, that, when the rocket is ascending, the fire will
play with great force on the tin, which will divide the tail in such
a manner, as to form an arch. If there is a short piece of port-fire,
of a strong charge, tied to the end of the stick, it will add greatly
to the appearance; but this must be lighted before fire is put to the
rocket.

_Sec. VIII. Of Swarmers, or Small Rockets._

Although swarmers are nothing more than rockets of a smaller size,
as from two ounces downwards, and are charged with the usual rocket
composition, which we have described; yet it may be necessary to make
some remarks respecting them.

Swarmers are sometimes fired in flights, or in a volley, and in
large aquatic fire-works. They are bored in the same manner as large
rockets, or pierced in the act of charging them. This is the case
with those of one and two ounces. All rockets, however, under one
ounce, are not bored, but must be filled to the usual height with
composition. The number of strokes for ramming these small swarmers
is not material, provided they are rammed true and moderately hard.
The necks of unbored rockets must be in the same proportion as in
common cases. The composition, with which small swarmers are charged,
generally consists of

Meal-powder, 4 oz.
Charcoal, or steel-dust, ¼ oz.

As to the swarmers which are pierced, or bored, _viz._ those of one
and two ounces; they are made, we observed, in the same manner as
large rockets, with the exception, that, when headed, their heads
must be put on without a collar. The number of strokes for driving
one-ounce cases must be eight, and for two-ounce, twelve.

_Sec. IX. Of Scrolls for Sky-Rockets, and of Strung, Tailed, Drove,
and Rolling Stars._

We have given, in a preceding chapter, the composition of various
stars, which are used for the decoration of sky-rockets, and other
species of fire-works. We shall, therefore, confine ourselves to
their application, and the different modes of preparing them for this
purpose.

_Scrolls_ are used as furniture, or decorations for sky-rockets, and
are so named from the spiral form they assume, when fired very quick
in the air. We may put into the head of a rocket, as many of the
cases as it will contain. Cases for scrolls should be four or five
inches in length, and their interior diameter, three-eighths of an
inch. One end of these cases must be pinched quite close before it is
filled; and, when filled, the other end must also be closed. Then, in
the opposite sides, make a small hole at each end, in the same manner
as in tourbillons, and prime them with priming paste, or meal-powder
and brandy.

_Strung Stars_, so named from having a cotton quick match run through
them, are formed by taking some thin paper, and cutting it into
pieces of about one and a half inches square, and laying on each
piece, as much dry star composition as the paper, when folded, will
easily contain. The paper, with its contents, is then twisted up
as hard as possible. When done, rub some paste between the hands,
and roll the stars between them, and afterwards dry them. They are
then covered with tow, and primed with a paste composed of meal
powder, and brandy, in which they may be rolled in the same manner as
described when treating of stars. They are then dried and strung on
cotton quickmatch, by piercing a hole through them, taking care to
put but ten or twelve on each match, and placing them at the distance
of three or four inches apart.

_Tailed stars_ are those which produce a great many sparks,
representing a tail like that of a comet. Of these, there are two
kinds, the rolled and the drove. The operation for the rolling of
stars, we have sufficiently explained; it consists in mixing the
composition with brandy, or, if it can be had, with spirit of wine,
and either weak gum water, or isinglass size, sufficient to make a
thick paste; and then rolling it.

When tailed stars are to be driven, the composition must be moistened
with spirit of wine, or if it cannot be had, with fourth proof
brandy, without the gum, or gelatin, and not made so wet as for
rolling. One or two-ounce cases, rolled dry, are best for this
purpose; and when they are filled, unroll the cases within three or
four rounds of the charge, and all that is unrolled must be cut off.
Then paste down the loose edge; and in two or three days afterwards,
cut them in pieces of five or six-eighths of an inch in length; then
melt some wax, and dip one end of each piece into it, so as to cover
the composition. The other end must be covered with priming paste.

_Drove stars_ are so designated, because the composition is always
drove, and used in cases. They are seldom put in rockets, but are
chiefly used for air-balloons. They are put in cases, to prevent the
composition from being broken, by the force of the blowing powder in
the shell. See _Air-Balloons_.

With respect to _rolling stars_, we gave, in our chapter on star
compositions, not only the proportion of their constituent parts, but
ample instructions for preparing them for use. They are usually about
the size of a musket ball; but sometimes they are made an inch in
diameter. When very small, they are called _sparks_. See _Stars_.

_Sec. X. Of Line-Rockets and their Decorations._

Line-rockets are the same as the _courantines_ of the French, or
rockets that fly along a rope. If a rocket be attached to an
empty case, and a rope passed through the latter, and stretched
horizontally; and if the rocket be then set on fire, it will run
along the rope, without stopping till the matter it contains is
exhausted.

Line-rockets do not differ materially from sky-rockets, as they
are made and driven like them; but they are without heads, and the
cases are cut close to the clay. They are sometimes made with six or
seven changes. Four or five, however, are the most common. We must
first have a piece of light wood, turned round, about two and a half
inches in diameter, with a hole through the middle, lengthwise, and
sufficiently large for a wire to go easily through. If four changes
are required, four grooves must be cut in the swivel, one opposite
the other, to lay the rockets in.

Having rubbed the mouths of the rockets with wet meal powder, lay
them in the grooves, head to tail, and tie them fast. From the tail
of the first rocket, carry a leader to the mouth of the second, and
from the second to the third, and so on to as many as there are on
the swivel, making every leader very secure; but in fixing these
pipes, care must be taken, that the quick match does not enter the
calibers of the rockets. The rockets being fixed on the swivel and
ready to be fired, have a line, 100 yards long, stretched, and
fixed up tight, at any height from the ground, but placed perfectly
horizontal. This length of line will answer for half-pound rockets,
but, if larger, the line must be longer. One end of the line,
before it is put up, is to be put through the swivel; and when the
line-rocket is fired, let the mouth of that rocket, which is set off
first, face that end of the line where the operator stands, and the
effect will follow in succession, _viz_: the first rocket will carry
the rest to the other end of the line, the second will bring them
back, and they will continue running out and in, according to the
number of rockets. At each end of the line, there must be a piece of
wood for the rocket to strike against, to prevent injury to the line.
Let the line be well soaped, and the hole in the swivel very smooth.

In order to vary the appearance, different decorations may be used
with the line-rockets; of these, _flying dragons_, _Mercuries_, &c.
are the most conspicuous. Another motion may be given to them, that
of revolving, in the following manner: Have a flat swivel, made very
exact, and tie on it two rockets obliquely, one on each side; which
will make it turn the whole length of the line, and form a circle of
fire. The charge for these rockets, should be a little weaker than
that usually employed.

It is apparent, that a variety of figures may be put in motion, and
consequently new appearances formed, by different contrivances. To
represent, for instance, two _fighting dragons_, we must have two
swivels, made square; and on each swivel, tie three rockets together,
on the under side. Then having two flying dragons, made of tin, fix
one of them on the top of each swivel, so as to stand upright, and
in the mouth of each dragon, put a case of common fire; and another
at the end of the tail. Two or three port-fires may also be put on
the sides of their bodies to illuminate them Put them on the line,
one at each end; but let there be a swivel in the middle of the
line, to keep the figures from striking together. Before the rockets
are fired, light the cases on the dragons, and, if care be taken in
firing both at the same time, they will meet in the middle of the
line. They will then turn, and run back with great violence. The line
for these rockets, must be very long.

_Sec. XI. Of Signal Sky-Rockets._

Signal rockets seldom exceed a pound in weight. Those which are
employed in the land and sea service, are sometimes capped, or
headed, and contain stars, serpents, &c. Two sorts of signals are
used when artificial works are to be exhibited; namely, one with
serpents, and the other without. Rockets which are to be bounced,
must have their cases made one and a half or two diameters longer
than the common proportion, and, after they are filled, a small
quantity of clay is put in. Then bounce and pinch them in the usual
manner, and fix on each a cap. Signal sky-rockets, without bouncers,
are only sky-rockets closed and capped. These are very light, and,
therefore, do not require such heavy sticks as those with loaded
heads. Signal rockets, with reports, are fired in small flights; and
are often, as well as those without reports, used for signals of the
commencement of an exhibition of fire-works.

Signal rockets may be seen at a great distance, and observed
instantly, when neither flags nor telegraphs could be observed
without glasses; and may be so formed, as even to communicate
particular orders or intelligence, by varying their decorations,
their mode of ascension, as in the caduceus rocket, and by several
other means.

CHAPTER VIII.

OF SUNDRY FIRE-WORKS, DENOMINATED AIR-WORKS.

Before we notice the various kinds of wheel-works, and their
appendages, we purpose to consider the formation of gerbes,
air-balloons, mortars, bombs, tourbillons, aigrettes, and some other
works.

_Sec. I. Of the Composition and Mode of forming large and small
Gerbes._

In preparing cases for gerbes, it is necessary that they should be
made strong; as they would be liable to burst, on account of the
strength of the composition, which comes out with great velocity.
They should be of the same thickness at top and bottom, and the paper
well pasted. Their necks should be long, in which case, the iron
would have more time to be heated, by meeting with more resistance in
its disengagement, than if the neck was shorter; for then it would be
burnt too wide before the charge was consumed. Long necks will throw
the stars to a greater height, which will not fall before they are
spent. They should rise and spread in such a manner as to resemble a
wheat-sheaf.

Gerbes are generally made about six diameters long, from the bottom
to the top of the neck. Their caliber must be one-fifth narrower
at top than at bottom. Their neck is one-sixth diameter, and
three-fourths long. There is a wooden foot or stand, on which the
gerbe rests. This may be made with a choak or cylinder, four or five
inches long, to fit the inside of the case, or with a hole in it to
put in the gerbe: both these methods will answer the same end. In the
charging of gerbes, there will be no need of a mould, the cases being
sufficiently strong to support themselves. Before this operation
is commenced, we must be provided with a piece of wood made to fit
in the neck. If this precaution is not used, the composition will
fall into the neck, and occasion a vacancy in the case, which will
inevitably burst it, the moment the fire reaches the air. A weak
composition should be put in at first, to the quantity of one or two
ladles full. After the case is filled, take out the piece of wood,
and fill the neck with slow charge.

Small gerbes, or white fountains, as they are sometimes called, are
usually made of four, eight, or sixteen ounce cases, of any length,
taking care to paste, and otherwise make them very strong. Before
they are filled, however, drive in clay one diameter of their orifice
high. When filled, bore a hole through the centre of the clay to the
composition. The ordinary proportion will answer for the vent, which
must be primed with a slow charge. Large gerbes are made by their
diameters, and their cases at bottom one-fourth thick. The interior
diameter of a gerbe is found, by supposing the exterior diameter of
the case, when made, to be five inches, by taking two-fourths for
the sides of the case, and there will remain two and a half inches
for the bore.

Gerbes produce a brilliant fire, and appear remarkably beautiful,
when a number of them are fixed in front of a building.

The composition of gerbes is similar to that of the Chinese fire. It
is to the cast-iron, which enters into it, that its beautiful effects
are to be ascribed. In fact, the composition of Chinese fire differs
considerably, as we shall notice, when we treat of it, according to
the purpose for which it is employed. It is adapted, for instance,
in various proportions of its constituent parts, to calibers of
different diameters, cascades, representation of palm trees, as well
as for large and small gerbes. The old formula for gerbes is the
following.

_Composition for Gerbes._

Meal-powder, 6 lbs.
Beat cast-iron, 2 lbs. 1½ oz.

The present formula, as we remarked when speaking of compositions
for calibers from three-quarters of an inch to an inch, is saltpetre
1 oz, sulphur 1 oz, meal-powder 8 oz, charcoal 1 oz, and pulverized
cast-iron 8 oz.

The vivid and rapid combustion which ensues, when this composition
is inflamed, cannot be accounted for in any other way, than that the
nitre is acted upon by the sulphur, the charcoal, and the iron; that
the gunpowder, during its combustion, raises the temperature to the
degree necessary for the decomposition of the nitre by the substances
mentioned; that sulphurous and probably sulphuric acid, as well as
carbonic acid, are generated, by the union of the sulphur and carbon
with a part of the oxygen of the nitre; that the iron undergoes a
combustion, both in contact with the nitre and with atmospheric air;
and, lastly, that the _effect_, which characterizes this composition,
and other similar compositions, into which cast-iron enters, as in
the celebrated Chinese fire, is to be attributed to the iron; and
the appearance which iron assumes, when in a state of combustion, is
owing to no other cause than its rapid combination with oxygen, by
which the metal is oxidized. (See _Iron_, in _Part_ I.)

_Sec. II. Of Paper Mortars._

It may not be improper, in this place, to give the manner of
forming paper mortars. These mortars are necessary for a variety of
exhibitions, as will appear hereafter.

Mortars are made of stout paper; or several sheets are pasted
together, and made into pasteboard, in the manner before described.
(See _Pasteboard_.) The preparations are various according to the
size required. For a coehorn mortar, which is 4 inches and 2/5ths in
diameter, roll the pasteboard on the former, on which it is made,
1/6th of its diameter thick, and, when dry, cut one end smooth and
even; then nail and glue it on the upper part of the foot. Afterwards
cut off the pasteboard at the top, allowing for the length of the
mortar, two and a half diameters from the mouth of the powder chamber.

The mortar is then bound round with a strong cord, wetted with glue.
The bottom of the foot, it being turned out of elm, is one diameter
and two thirds broad, and one diameter high, and the part which goes
into the mortar is two-thirds of its diameter in height. The copper
chamber for the powder, which is separate from this, is made in a
conical form, and is one-third of the diameter wide, and one and a
half of its own diameter long. In the centre of the bottom of this
chamber, make a small hole, a short distance down the foot; this hole
must be met by another of the same size, made in the side of the
foot. If these holes are made true, and a copper pipe fitted into
both, the mortar, when loaded, will prime itself; for the powder will
naturally fall to the bottom of the first hole. By putting a piece of
quick match to the side, it will be prepared for firing.

When mortars of a larger size than ten inches in diameter are
required, it is better to have them made of brass. See further
observations on this subject in section seventh of this chapter, in
the article on _fire-pots_.

_Sec. III. Of Mortars to throw Aigrettes, &c._

Shells are filled with a variety of pyro-preparations, as stars,
rains, serpents, &c. These are put in first, and then the blowing
powder, as it is called; but the shells must not be quite filled.
They must be introduced into the shells through the fuse hole. Some
substances, however, as marrons, being too large to go through the
fuse hole, must be put in before the shell is closed. When the shells
are loaded, glue and drive in the fuses very tight. With respect
to the diameter of the fuse hole; for a coehorn balloon, let the
diameter be seven-eighths of an inch; for a balloon, five and a half
inches in diameter, make the fuse hole one inch and one-sixth in
diameter; for an eight-inch balloon, one inch and three-eighths; and
for a ten-inch balloon, one inch and five-eighths.

Air-balloons are divided, according to the substances they contain,
or the effect they are to produce, and are usually of four kinds;
namely, 1. Illuminated air-balloons, 2. Balloons of serpents, 3.
Balloons of reports, marrons, and crackers, 4. Compound balloons.
Balloons and shells, in fire-works, are the same.

In the following view of the different balloons, we have given
the number and quantity of each article for the different shells,
designating their kind and character:

_Coehorn balloon Illuminated._

Meal-powder, 1½ oz.
Grain, do. ½ --
Powder for the mortar, 2 --

Length of the fuse composition, three-quarters of an inch: 1 oz.
drove or rolled stars, as many as will nearly fill the shell.

_Coehorn balloon of Serpents._

Meal-powder, 1½ oz.
Grain, do. ½ --
Powder for the mortar, 2¼ --

Length of the fuse composition 13/16ths of an inch: half-ounce cases,
driven three diameters, and bounced three diameters, and half-ounce
cases, driven two diameters and bounced four diameters, of each, an
equal quantity; and as many of them as will fit in easily, placed
head to tail.

_Coehorn balloons of Crackers and Reports._

Meal-powder, 1¼ oz.
Grain, do. ¾ do.
Powder for the mortar, 2 do.

Length of the fuse composition 3/4 of an inch; reports 4, and
crackers of six bounces, as many as will fill the shell.

_Compound Coehorn Balloons._

oz. dr.
Meal-powder, 1 4
Corn, do. 0 12
Powder for the mortar, 2 4

Length of the fuse composition 13/16ths of an inch: 1/2 oz. cases
driven 3-1/2 diameters, and bounced 2, 16; 1/2 ounce cases driven 4
diameters and not bounced, 10; rolled stars, as many as will complete
the balloon.

_Balloons illuminated (Republican)._

oz. dr.
Meal-powder, 1 8
Grain, do. 0 12
Powder for the mortar, 3 0

Length of the fuse composition 15/16ths of an inch; 2 oz. strung
stars, 34; rolled stars, as many as the shell will contain, allowing
for the length of the fuse.

_Balloon for Serpents, (Republican)._

oz. dr.
Meal-powder, 1
Grain, do. 1 8
Powder for the mortar, 3 8

Length of the fuse composition, 1 inch; 1 oz. cases driven 3-1/2 and
4 diameters, and bounced 2, of each an equal quantity, sufficient to
load the shell.

_Balloons with crackers and Marrons. (Rep.)_

oz. dr.
Meal-powder, 1 8
Corn powder, 1 4
Powder for the mortar, 3

Length of the fuse composition 14/16ths of an inch; reports 12; to be
completed with crackers of 8 bounces.

_Compound balloons (Republican)._

oz. dr.
Meal-powder, 1 5
Corn powder, 1 6
Powder for the mortar, 3 12

Length of the fuse composition, one-inch; 1/2 ounce cases driven and
bounced 2 diameters, 8; 2 oz. cases filled 3/8ths of an inch with
star-composition, and bounced 2 diameters, 8; silver rain falls, ten;
2 oz. tailed stars, 16; rolled brilliant stars, 30. If this should
not be sufficient to load the shell, it may be completed with gold
rain falls.

_Eight-inch balloons Illuminated._

oz. dr.
Meal-powder, 2 8
Grain powder, 1 4
Powder for the mortar, 9

Length of the fuse composition, one inch and 1/8th; 2 oz. drove
stars, 48; 2 oz. cases, driven with star composition, 3/8ths of an
inch, and bounced 3 diameters, 12; and the balloon completed with 2
oz. drove brilliant stars.

_Eight-inch Balloons of Serpents._

oz. dr.
Meal-powder, 2 0
Corn powder, 2 0
Powder for the mortar, 9 8

Length of the fuse composition, 1 inch and 3/16ths; 2 oz. cases
driven one and a half diameters, and bounced 2, and one-ounce cases
driven 2 diameters, and bounced 2-1/2; of each an equal quantity,
sufficient for the shell.

We may remark, that the star composition, driven in bounced cases,
must be managed in the following manner: First, the cases must be
pinched close at one end, then the corn-powder put in for a report,
and the case pinched again close to the powder, only leaving a small
vent for the star-composition, which is driven at top, to communicate
to the powder at the bounce end.

_Compound eight-inch Balloon._

oz. dr.
Meal-powder, 2 8
Corn powder, 1 12
Powder for the mortar, 9 4

Length of the fuse composition, 1/8th of an inch; 4 oz. cases, driven
with star composition, 3/8th of an inch, and bounced 3 diameters,
16; 2 oz. tailed stars, 16; 2 oz. drove brilliant stars, 12; silver
rain falls, 20; 1 oz. drove blue stars 20; and 1 oz. cases driven and
bounced, two diameters, as many as will fill the shell.

_Another of eight-inches._

oz. dr.
Meal-powder, 2 8
Corn, do. 1 12
Powder for the mortar, 9 4

Length of the fuse composition, 1 inch and 1/8th; crackers of
six reports, 10; gold rains, 14; 2 oz. cases driven with star
composition, 3/16ths of an inch, and bounced 2 diameters, 16; 2 oz.
tailed stars, 16; 2 oz. drove brilliant stars, 12; silver rains, 10;
1 oz. drove blue stars, 20; and 1 ounce cases, driven with brilliant
charge, 2 diameters, and bounced 3, as many as the shell will hold.

_A compound ten-inch Balloon._

oz. dr.
Meal-powder, 3 4
Corn powder, 2 8
Powder for the mortar, 12 8

Length of the fuse composition 15/16ths of an inch; 1 oz. cases
driven and bounced 3 diameters, 16; crackers of eight reports, 12;
4 oz. cases, driven 1/2 an inch with star composition, and bounced
2 diameters, 14; 2 oz. cases driven with brilliant fire 1 and 1/4th
diameters, and bounced 2 diameters, 16; 2 oz. drove brilliant stars,
30; 2 oz. drove blue stars, 3; gold rains, 20; silver rains 20. After
all these are put in, fill the remainder of the case with tailed and
rolled stars.

_Ten inch balloons of three charges._

oz. dr.
Meal-powder, 3 0
Corn-powder, 3 2
Powder for the mortar, 13 0

Length of the fuse composition, 1 inch: the shell must be loaded
with 2 oz. cases, driven with star composition 1/4th of an inch, and
on that one diameter of gold-fire, then bounced three diameters;
or with 2 oz. cases, first filled one diameter with gold fire, then
one and one-fourth diameters of brilliant fire. These cases must be
well secured at top of the charge, lest they should take fire at both
ends: but their necks must be larger than the common proportion. For
the manner of forming _balloon cases_ of paper, consult the article
on that subject, in a preceding chapter.

Balloons, the _bombs_ of some, may be formed of different sizes, and
made proportionably strong.

Bombs may be formed of wood by turning it round, and hollow, of a
sufficient thickness, and in two parts, which fit each other like a
common snuff box. The inferior or lower part must be made thicker
than the upper, as it rests upon the powder; and for the same reason,
that iron bombs are cast thicker at their bottom. One-twelfth of the
diameter is considered a sufficient thickness for the under part, and
one-fifteenth for the upper part, which is pierced with a hole to
receive the fuse. This hole is called the eye of the bomb.

When balloons, or bombs, are to be charged, the decorations may be
varied in the same manner as for sky-rockets. Stars, golden rain, and
meteors, are considered the best, as they produce the most brilliant
effect.

After the addition of the furniture or decorations, we finish the
charge by putting in coarse grain powder, which is introduced through
the eye. The fuse is then driven in. It is glued, in order to secure
it. The bomb is now covered with three or four turns of canvass, and
over this some paper, to secure it. In this state, it ought not to be
more than 1/11th of an inch smaller than the caliber of the mortar.
This leaves what is denominated the windage.

When the bombs are well dried, the fuse is primed with a double
match, and priming paste. A cup, made with two turns of paper, is
then attached to the fuse, which receives the double match.

The bomb, thus prepared, is then placed in a cone made of pasteboard,
which contains the powder of the charge, or that required for its
ascension, and is put into the mortar. One of the matches above
described, communicates the fire to the fuse, and the other at
the same time to the powder in the cone. The match, it is to be
observed, comes out of the mouth of the mortar, and serves to fire
it. This mode of discharging the mortar, differs from the one we have
previously given.

The following table exhibits the calibers for bombs, the length of
the fuse for each caliber, and the weight of the powder required for
the charge.

Having made some remarks respecting bombs, we will now offer a few
observations concerning mortars; and although we have, on a former
occasion, mentioned something respecting them, yet we deem a few
remarks on this head not improper at this time.

_Mortars_, from five to six inches bore, are usually made
of pasteboard and canvass. The canvass is first soaked in a
gelato-amylaceous paste, or paste composed of half glue and half
flour; and, when put on, is covered with sheets of pasteboard, which
are glued or pasted. For various kinds of paste, see _Pasteboard_.

When the case, or mortar is to be formed, cylinders of wood as
_formers_ are employed. They are of different diameters, according
to the size of the mortars, that are to be made. For four-inch
mortars, inch formers; for six-inch, one and a half inch formers,
&c. After they are rolled and pasted on the former, they are dried
on it. As to their strength, this depends on the thickness of the
case. A mortar of four inches in interior diameter, ought to be six
inches in exterior diameter, and those of six in interior, should be
nine, exterior. The cases being formed, we next have turned as many
cylinders of walnut, as cases or pots. These cylinders are short. In
each is formed a conical chamber, in the shape of the letter V, which
is afterwards lined with tin or brass, to prevent the action of the
powder. They are then glued and put into the end of each pot, about
the length of an inch, and further secured by nails.

The chamber is designed to receive the powder, and its conical form
enables it to act with all its force immediately on the bomb. A flat
bottom would not have this advantage, as the powder in that case
would have more room, and consequently its force be divided. They are
sometimes, however, made flat.

The charge for these mortars, as a general rule, is 1/30th part of
the weight of the bomb.

When mortars are to be larger than the sizes we have mentioned, it
is necessary to have them of metal, and for this purpose copper is
generally employed. Its thickness should be one-fourth of an inch,
for a nine-inch mortar; and half an inch, for twelve-inch mortars. A
cone of copper is to be made in the same way as above mentioned. This
is secured, and made solid by means of lead.

In experiments and exhibitions, the powder, we may observe, must be
of the same strength.

We find then, that mortars, for the discharge of bombs, or balloons,
are differently made from those which are used for throwing
iron-shells. In fire-works, the design of mortars is to project the
balloon in a vertical direction, which, being furnished with a fuse
as in ordinary shells, receives the fire from the gun-powder; and
at a given time, according to the length of the fuse, the fire is
communicated to the balloon, which bursts and scatters its contents
in the atmosphere. The furniture for balloons being various, and in
a larger quantity than could be contained in the heads of rockets,
(except the Congreve,) the appearance is more grand and impressive.
It is obvious, that, when they burst, fire is communicated to the
whole at the same time; and the quantity of powder is usually
sufficient, not only to burst the shell, but also to throw the
contents to some distance. The height, to which balloons ascend,
depends, of course, on the quantity of gunpowder put in the mortar.
The quantity is generally regulated.

We find, also, that two modes are used for discharging the mortars.
The one consists in having a communication from without to the bottom
of the cone, which contains the powder, and applying the match to
this vent, on the same principle as that for firing a cannon, or
common mortar. The other, by firing a quick-match in the conical
cavity, and putting in the charge with the balloon; letting the
match, however, be of a sufficient length to come out of the mouth
of the mortar, and fall over its side. This match, when fired, will
communicate fire to the powder in the cone, and produce the same
effect. Metallic cylinders, and especially copper, however small, are
certainly preferable to those made in the usual manner.

_Sec. IV. Of making Balloon Fuses._

Wood, particularly beech, is generally employed for forming fuses,
which is turned of the shape required. If made with pasted paper,
they will answer for the purpose of fire-works. The diameter of the
former for fuses for coehorn balloons must be half an inch; for a
republican fuse, five-eighths of an inch; for an eight-inch fuse,
three-fourths of an inch; and for a ten inch fuse, seven-eighths of
an inch. Having rolled the cases, pinch and tie them almost close
at one end; then drive them down, and let them dry. Before they are
filled, mark on the outside of the case, the length of the charge
required, allowing for the thickness of the bottom; and when the
composition is rammed in, take two pieces of quick-match about six
inches long, and lay one end of each on the charge, and then a little
meal-powder, which is to be rammed down loose. The loose ends of the
match, double up, and place in the top of the fuse. This top must be
covered with a proper cap to keep it dry. When the shells are put
into the mortars, uncap the fuses, and pull out the loose ends of
the match, and let them hang on the sides of the balloon. The use of
the match is to receive the fire from the powder in the chamber of
the mortar, in order to light the fuse. When the shell is put in the
mortar, its fuse must be uppermost, and exactly in the centre. Some
meal-powder is usually sprinkled upon it.

Fuses of wood are longer than those of paper, and not bored through,
but left solid about 1/2 an inch at bottom; so that, when used,
this end is cut off. They are sawed, however, at a proper length,
measuring the charge from the cup at top. On the subject of _Fuses_,
see the last part of the work.

Fuses for bombs, Morel remarks, are formed of five thicknesses of
paper, or of pasteboard, made of that thickness; and the former, on
which the fuse case is rolled, should be one-third diameter. The
composition is put in with a spoon, and each charge is driven with
twenty strokes of a moderate size mallet.

_Composition for the fuses of bombs or balloons._

1. Meal powder, 12 oz.
Sulphur, 4 --
Charcoal, 6 --

2. Saltpetre, 1 lb. 10 --
Sulphur, 8 --
Meal powder, 1 lb. 6 --

3. Saltpetre, 1 lb. 8 --
Sulphur, 8 --
Meal powder, 1 lb. 8 --

_Sec. V. Of the Mosaic and Common Tourbillon._

The _tourbillon de feu_ of the French, or whirlwind of fire,
is the same as the _soleil montant_; because it ascends in full
illumination, and scatters fire in various directions. The
tourbillon, therefore, receives its name from the effect it produces.
It raises itself very high, and forms a whirl of fire and terminates
in two coronal figures, or crowns, which descend in what are called
parasols. It does not, however, produce crowns, except when it is
charged with Chinese fire.

There are two kinds of tourbillons, which we will describe, namely,
the mosaic and the common. The mosaic produces a tail of some length,
and after whirling round, finishes with a report. This effect is
owing to its particular structure and formation, as it differs from
the common tourbillon. In preparing the cases for mosaic tourbillons,
pasteboard, formed of five sheets of paper, is used. They are made
seven inches in length upon a roller or former 5/12ths of an inch in
diameter. Their thickness, when rolled, is 1/8th of an inch. They
are choaked in the usual manner, and the excess of the string is cut
off. After having put a quarter of an inch of earth into a case,
and beating it with ten or twelve blows with the mallet, we mark
the height of the earth on the outside of the case. We then load it
to the height of 7/12ths with the composition heretofore mentioned.
Another quarter of a spoonful of earth is then put in. We then choak,
and bind the case in this place. Two fingers of grain powder are now
added; we again choak, and bind it above this. We put in the same
composition, after the last operation, to the height of 7/12ths of an
inch. The choaking, it is to be observed, must not wholly close the
case; so that the composition can set fire to the powder.

We now introduce a spoonful of earth, and choak and bind as before.
It is then finished by charging it with 7/12ths of an inch of
composition. The remainder of the case is cut, and the composition
primed.

Cases, thus prepared, are afterwards treated in the following manner:
We pierce three holes in the sides of each, one a little above the
last choak, another through, or into the case, to penetrate the last
charge, and the third through the first charge. These holes have
a communication with each other by means of quickmatch; so that,
when the match is set on fire, the two extremes are inflamed at the
same time, and being opposed to each other, give a rotary motion to
the tourbillon, which, when the powder inflames, terminates by an
explosion. The holes ought to be covered with three or four turns of
pasted paper. It is then ready to be put into the _pots de chasse_.
When completed, the tourbillon should not exceed 10/12ths of an inch
in diameter.

The _pots de chasse_ (mortars somewhat similar to those described)
should be made of pasteboard, prepared with eight thicknesses of
paper, and moulded upon a roller of 11/12ths of an inch in diameter.
They are mounted in the same manner as _fire-pots_, and are also
primed in the same way.

Into each pot there is put four drachms of broken grain powder,
and a slip of pasteboard, pierced with five or six holes, which is
introduced by means of a stick. A little meal-powder is then put into
the pot, and afterwards the tourbillon, the primed end of which must
be above the _chasse_. It is then closed with paper, made into a wad
or ball, and the pot is secured with a slip of pasteboard, pasted on
it.

_Composition of Mosaic Tourbillons._

1. Meal powder, 16 oz.
Charcoal, 3 or 4 dr.

2. Meal powder, 16 parts.
Charcoal, 3⅓ ----

Common tourbillons differ in many respects from the mosaic, although
their motion is the same. There are two methods of forming them as
well as their appendages, both of which we purpose to describe. The
first is the following: Having filled some cases within about 1-1/2
diameters, drive in a handful of clay, prepared, of course, in the
manner described in the first part of the work; then pinch their ends
close, and drive them down with a mallet. Then find the centre of
gravity of each case; where you nail and tie a stick, which should
be 1/2 an inch broad at the middle, and run a little narrower to the
ends; these sticks must have their ends turned upwards, so that the
cases may turn horizontally on their centres. At the opposite sides
of the cases, at each end, bore a hole close to the clay, with a
gimblet the size of the neck of a common case of the same nature.
From these holes, draw a line round the case, and, at the under
part of the case, bore a hole with the same gimblet, within half a
diameter of each line, towards the centre; then from one hole to the
other, draw a right line. This line divide into three equal parts,
and bore a hole near to each of the ends; then from these holes to
the other two, lead a quick-match, over which paste a thin paper.

It is to be observed, that there is a stick about the length of the
case, which goes across it, and is securely fastened by a cord, that
the whole lies flat upon a table before it is fired, and hence, it is
sometimes named the _table tourbillon_; and, that the leader should
be carried from one side hole to the other, the holes being made at
the opposite sides, as before mentioned. When tourbillons are fired,
they must lay upon a smooth table, with their sticks downwards, the
leader being set on fire in the middle with a port fire. They should
spin two, three, or four seconds round the table, before they rise,
which is about the time the composition will be burning from the side
holes to those at the bottom.

Reports, or detonating cases, may be fixed to tourbillons, if so
required. In this case, we make a small hole in the centre of the
case at top, and in the middle of the report make another. Then place
them together, and tie on the report, and, with a single paper,
secure it from fire. By this method, small cases of stars, rains, &c.
may be fixed on tourbillons, being careful, nevertheless, that they
are not overloaded.

One-eighth will be a sufficient thickness for the sticks, and their
length equal to that of the cases.

The other mode of forming common tourbillons, is the following: They
are made with cases of an inch, which are choaked and bound in the
usual manner. In filling, we make two wads of paper of the same size,
and put one of them into the case, and ram it with fifteen or twenty
blows. We then mark upon the case, the height of this wad, which is
afterwards driven with the composition, given at the end of this
section. To each charge, thirty strokes of a moderate size mallet,
will be required; and each charge should not be more in height in the
case than nine exterior diameters. We mark, on the outside of the
case, the height of this charge, and put in a wad of the same kind
and size as the former one. We drive this in the same manner as the
first, and then choak and bind the case. After cutting off the excess
of the ligature, with which we bound the case, we again introduce
the rammer, and give it eighteen blows with the mallet, in order to
flatten the choak.

We afterwards divide the case parallel to each end, into four equal
parts, and mark the height of the wads. That of the middle, which
becomes in fact the bottom of the case, (from the manner it is fixed
for ascension), we divide into five equal parts from one point to
the other, and pierce a hole in each division to the composition.
We then make, on a level with the wads, upon the lateral lines, two
similar holes; one upon one side, and the other on the other side,
at the opposite ends. These holes are so made as that the case has
four holes on one line, and one upon each of the other two. Each
hole is then primed with a piece of quick match, and priming paste.
One of these matches must pass over all the other holes; so that the
fire may be communicated from one to the other at the same time. The
matches are then covered with a band of pasted paper. To hold the
tourbillon in a horizontal position, we procure a hoop of the same
thickness and diameter as the length of the case; and on the plate,
we make a groove for the match of communication, which is supported
between the four holes with an iron wire. If the case whirls round
with a uniform motion, it is well balanced.

The four holes beneath, serve to raise it in the air, and the two
lateral apertures give it a revolving motion.

When tourbillons are to be set off, they must be balanced either by a
cross stick, as in the first instance, or some other contrivance. The
effect is the same as before described.

_Composition for Tourbillons, or Table Fusées, of different Calibers._

-------------+----------------+-------------------+------------------
Substances. |Calibers of ⅓d |Of ⅔ds of an inch |Of ⅚ths of an inch
| of an inch. |with Chinese fire. | with Chinese fire.
-------------+----------------+-------------------+------------------
Saltpetre, | 8 oz. | 16 oz. | 16 oz.
Sulphur, | 4 oz. | 8 oz. | 8 oz.
Meal-powder, | 16 oz. | 18 oz. | 16 oz.
Charcoal, | 1 oz. | |
Pulverized | | |
cast iron, | | 10 oz. | 12 oz.

_Another composition for a caliber of half an inch, of common fire._

Saltpetre, 16 oz.
Sulphur, 4 --
Meal-powder, 7 --
Charcoal, 4 --

The following formulæ are sometimes used;

_For four-ounce tourbillons._

Meal-powder, 2 lbs. 4 oz.
Charcoal, -- 4½ --

_For eight-ounce tourbillons._

Meal powder, 2 lbs.
Charcoal, 4¾ oz.

_For large tourbillons._

Meal-powder, 2 lbs.
Saltpetre, 1 do.
Sulphur, 8 oz.
Beat-iron, 8 oz.

As a general rule, we may remark, that the larger tourbillons are
made, employing, if necessary, different coloured fires, the weaker
must be the charge; and, on the contrary, the smaller, the stronger
their charge.

_Sec. VI. Of Mortars for throwing Aigrettes, and the manner of
loading and firing them._

Pots of aigrette, when inflamed, exhibit the appearance of an
aigrette, or cluster of rays, such as are produced by diamonds, when
they are arranged in a particular way. The aigrette takes its name
from a bird, whose feathers serve to make up an ornament for the
head. It was given in diamonds, as a particular mark of distinction,
by the Grand Signior, to Lord Nelson, after the battle of the Nile.
There are aigrettes made of glass.

For the purpose of throwing aigrettes, the mortars are generally made
of pasteboard, of the same thickness as balloon mortars, and two and
a half diameters long in the inside from the top of the foot. The
latter must be made of elm without a chamber, but flat at top, in
the same proportion as those for balloon mortars. These mortars must
be bound round with a cord as before mentioned. Sometimes eight or
nine of these mortars, of about three or four inches in diameter, are
bound altogether, so as to appear as one; but when they are prepared
for this purpose, the bottom of the foot must be of the same diameter
as the mortars, and only one-half a diameter high. Having bound the
mortars together, fix them on a heavy solid block of wood. To load
them, place over the inside bottom of each, a piece of paper, and
spread on it one and a half ounces of meal and grain powder mixed;
then tie the serpents up in parcels with quickmatch, and put them in
with their mouths downwards. Care must be taken, that the parcels do
not fit too tight in the mortars, and that all the serpents have been
well primed, or wetted with the paste of meal powder and spirit of
wine.

On the top of the serpents, in each mortar, lay some paper or tow;
then carry a leader from one mortar to the other, and from all the
outside mortars to that in the middle. These leaders are to be put
between the cases and the sides of the mortar, down to the powder
at bottom. In the centre of the middle mortar, fix a fire pump, or
brilliant fountain, and sufficiently long to project out of the mouth
of the mortar. Then secure the mortars, by pasting paper over their
tops.

The _nest of serpents_ (as mortars thus prepared are called) is fired
by lighting the fire-pump, which, when consumed, will communicate to
all the mortars at once by means of the leaders.

Single mortars are called _pots des aigrettes_. If the mortars,
when loaded, are sent to any distance, or liable to be much moved,
the firing powder should be secured from getting amongst the
serpents, which would endanger the mortars, as well as injure their
performance. To prevent this accident, the mortars are to be loaded
in the following manner; First, put in the firing powder, and spread
it equally; then cut a round piece of blue touch paper, equal to the
exterior diameter of the mortar, and draw a circle on it equal to its
interior diameter, and notch it as far as that circle: then paste
that part, which is notched, and put it in the mortar close to the
powder, and stick the pasted edge to the mortar. This will secure the
powder at the bottom, so that it may be moved and carried without
receiving any damage.

For mortars of six, eight, or ten inches diameter, the serpents
should be made in one and two-ounce cases, six or seven inches long,
and fired by a leader, brought out of the mouth of the mortar, and
turned down the outside; its end being covered with paper, to prevent
the sparks of the other works from setting it on fire. For a six-inch
mortar, let the quantity of powder for firing be two ounces; for an
eight-inch, two ounces and three-quarters; and for a ten-inch, three
ounces and three-quarters. Care must be taken in these, as well as
small mortars, not to put the serpents in tight, for fear of bursting
the mortars. These mortars may be loaded with stars, crackers, &c.

_Sec. VII. Of Making, Loading, and Firing Pots des Brins._

These are formed of pasteboard, and must be rolled pretty thick.
They are usually made three or four inches in diameter, and four
diameters long; and pinched at one end like common cases. A number
of these are placed on a plank in the following manner: Having
fixed on a plank two rows of wooden pegs, cut, in the bottom of
the plank, a groove the whole length, under each row of pegs. Then
through the centre of each peg, bore a hole down to the groove at
bottom, and, on every peg, fix and glue a pot, whose mouth must fit
tight on the peg. Through all the holes, run a quick-match, one end
of which must go into the pot, and the other into the groove, having
a match laid in the groove from end to end, and covered with paper;
so that, when lighted at one end, it may discharge the whole almost
at the same instant. In all the pots, put about one ounce of meal
and grained powder. Then in some put stars, and in others rains,
snakes, serpents, crackers, &c. When they are all loaded, paste paper
over their mouths. Two or three hundred of these pots being fired
together, make a brilliant appearance by affording so great a variety
of fires.

_Sec. VIII. Remarks respecting Fire Pots._

Fire pots, called also _pots of ordnance_, in pyrotechny, are
nothing more than vessels used in, as well as for, the exhibition of
artificial fire-works. They are generally formed of thick pasteboard,
made by pasting together six or eight sheets of paper, of two inches
interior diameter, three inches exterior diameter, and fifteen
inches long. They are always placed upon a solid block or plank, and
preserved in a firm position. There is a stopper or plug made of
wood, which goes one inch into each case or pot, and is there glued
and secured by nails. This plug is turned with a screw, which enters
the plank, and preserves the pot in a steady position. The plank, on
which the pots rest, is usually three inches wide, an inch and a half
thick, and sufficiently long to receive twelve pots, placed at the
distance of half an inch apart. Before the pots are fixed on, a hole
is made through each plug in its centre, to receive a quick match,
which passes through to the composition. A groove is also made in
the plank, in its length, one-third of an inch square; and in such
a manner, that the holes, which communicate to the interior of the
pots through the plugs, must come in the middle of the groove. When
the quick-match is put through the plugs, to communicate with the
interior of the pots, we must leave about two inches on the outside.
At each hole, also, we put some priming paste, and then permit it to
dry.

If it is required to discharge them all at once, this may be done by
making a communication through the groove, by means of leaders in
the manner before mentioned; and covering the leaders with four or
five bands of paper, and setting the match or leader on fire. If, on
the contrary, they are to go off in succession, the groove is filled
with bran, which is pressed with the fingers, and is then covered
with paper. The match of communication with the pots must, however,
be preserved. The bran causes the fire to communicate gradually from
one to the other.

Pots are charged in the following manner: We first make the _sacs
of powder_. For this purpose, we have as many squares of paper as
there are pots, which are made into cylinders on the same roller
that formed the pots. Into each is put about an ounce of the
charge-composition, hereafter mentioned, with two pieces of match,
sufficiently long to come out an inch. They are then closed and
tied, and the excess is cut off. One of these sacs is put into each
pot, having previously pierced it with several small holes, and
sprinkled it with meal powder. After this, the garnishing, furniture,
or decoration is added, always observing to put the primed part
downwards. A wad of paper is then put over the whole, and the mouth
is closed with pasted paper.

_Composition of the charge for fire pots._

Gunpowder, in broken grains, 16 oz.
Charcoal, 3 --

Fire pots are discharged in the way we have described, which is
considered the best and most certain; or they may be fired by
communicating the fire with a match, passing out of the mouth, and
hanging over the sides. Another mode may be used, similar to that for
discharging balloons or bombs, but on a scale proportionate thereto.
Pots may be discharged in any direction; hence two pieces, or sets,
may be fired adversely, like rockets from the regulated rocket case.
Their effect depends, as we have frequently observed, on their
furniture or decorations.

The strength of fire pots is also to be considered. If they are made
three inches in interior diameter, it is prudent to cover them with
stout canvass, or small cord, wrapped round and covered with a coat
of glue, in the same manner as for tourbillons.

Fire pots are calculated to throw serpents, &c. in the air. Mortars,
it will be recollected, are designed to discharge shells or balloons,
which are thrown to a considerable height, by the powder placed
in the conical cavity; whereas fire pots, although their contents
are thrown out by blowing powder, are differently made at the
bottom, and merely designed to project serpents, stars, &c. to a
small distance. Being primed, they take fire as they pass out of
the pot. The charge is sometimes gunpowder, and, as above, composed
of gunpowder and charcoal, to lessen the power of the former. The
principle, on which they are discharged, is the same. Fire pots are
called pots of ordnance, because they are used for discharging sundry
substances, by means of gunpowder.

CHAPTER IX.

OF PARTICULAR COMPOSITIONS.

_Sec. I. Of Fire-Jets, or Fire-Spouts._

Fire-jets are produced by certain compositions, which are employed in
cases, and are charged solid. They are formed and used according to
taste or fancy.

The jets are made with a caliber of from one-third of an inch, to one
inch and one-third, in interior diameter. They are seven or eight
exterior diameters in length, and are charged in the usual manner
with the composition, hereafter mentioned, driving each charge with
twenty blows with a small mallet. The first charge must be the common
fire composition.

Some of the compositions in the following table have already been
mentioned, when treating of certain fire-works; but we deem it of
importance to notice them in a connected manner, so that we may have
the formulæ in one view.

Fire-jets, it must be remembered, are calculated as well for turning,
as for fixed pieces.

_Common Fire for calibers of one-third of an inch._

Meal-powder, 16 oz.
Charcoal, 3 --

_Common Fire for calibers of five-twelfths to half an inch._

Meal-powder, 16 oz.
Charcoal, 3 -- 4 dr.

_Common fire for calibers above half an inch._

Meal-powder, 16 oz.
Charcoal, 4 --

_Brilliant fire for ordinary calibers._

Meal-powder, 16 oz.
Filings of iron, 4 --

_Another, more beautiful._

Meal powder, 16 oz.
Filings of steel, 4 --

_Another, more brilliant, for any caliber._

Meal powder, 18 oz.
Saltpetre, 2 --
Filings of steel, 5 --

_Another, very brilliant, for two-thirds of an inch caliber, and
above._

Meal powder, 16 oz.
Saltpetre, 1 --
Sulphur, 1 --
Filings of steel, 7 --

_Brilliant fire, more clear, for any caliber._

Meal powder, 16 oz.
Filings of needles, or of needle steel, 3 --

_Silver-rain for calibers above two-thirds of an inch._

Meal powder, 16 oz.
Saltpetre, 1 --
Sulphur, 1 --
Filings of steel, fine, 4 -- 4 dr.

_Grand jessamine, for any caliber._

Meal powder, 16 oz.
Saltpetre 1 --
Sulphur, 1 --
Filings of spring steel, 6 --

_Small jessamine, idem._

Meal powder, 16 oz.
Saltpetre, 1 --
Sulphur, 1 --
Filings of steel, the best, 5 --

_White fire, idem._

Meal powder, 16 oz.
Saltpetre, 8 --
Sulphur, 2 --

_White fire, idem._

Meal powder, 16 oz.
Sulphur, 3 --

_Blue fire, for parasols and cascades._

Meal powder, 8 oz.
Saltpetre, 4 --
Sulphur, 6 --
Zinc, 6 --

_Another blue fire, for calibers of half an inch, and upwards._

Saltpetre, 8 oz.
Meal powder, 4 --
Sulphur, 4 --
Zinc, 17 --

The cases charged with this composition are only employed for
furnishing the centre of some pieces, the movement of which depends
on other cases; for these, having no force, would not move the piece.

_Blue Fire, for any caliber._

Meal powder, 16 oz.
Saltpetre, 2 --
Sulphur, 8 --

_Radiant Fire, idem._

Meal powder, 16 oz.
Filings of pins, (_d'epingles_) 3 --

_Green Fire, idem._

Meal powder, 16 oz.
Filings of copper, 3 -- 2 dr.

_Aurora Fire, idem._

Meal powder, 16 oz.
Gold powder, (_Poudre d'or_) 3 --

_For Italian roses or fixed stars._

Meal powder, 2 oz.
Saltpetre, 4 --
Sulphur, 1 --

_Another, for the same._

Meal-powder, 12 oz.
Saltpetre, 16 --
Sulphur, 10 --
Antimony, 1 --

The jets of fire, which are various according to the composition
employed, may appear under several forms, sometimes in one and
sometimes in another; and hence they may put on an asteroid
appearance, or that of a fountain, or water spout, or the form of
rain. The effect, however, is very elegant; and, in conjunction
with other species of fire-works, cannot fail to change the general
appearance, by modifying the whole, or rendering it more various.

These compositions are generally used in the manner before mentioned,
in cases of different sizes; but they may, under particular
circumstances, be employed otherwise. In fact, the _forms_ which may
be given to the flame of gunpowder, or the substances which compose
it, either by increasing or retarding its combustion, or changing the
appearance of the flame, and giving it the form of jets, stars, rain,
&c. are so numerous, that it furnishes alone an important branch of
Pyrotechny. These effects will be detailed, when we treat of the
formation of compound works.

_Sec. II. Of Priming and Whitening Cases, and Remarks concerning
Spunk and Touch Paper._

When the cases are charged, we pierce them with a small awl, or make
a hole with a gimblet in the end, if it should be stopped with clay,
or _probe_ them with a drill, as fire-workers call it, in the hole
which had been filled, in which we put some more of the composition.
This precaution is considered necessary, in order that the earth
should not cover internally the hole of the piercer. A piece of match
is then introduced, which extends on the outside, and is secured
there with a plug of wood.

Brown paper, made either of linen or cotton, but not of woollen
cloth, when soaked in a concentrated solution of saltpetre, is, we
have said, rendered very combustible, and will convey fire for small
works with much facility. It is this paper, called touch, or more
properly match, paper, that is used for capping, &c. Paper of this
kind may sometimes be used, as for _crackers_, _serpents_, &c. Cotton
quick-match, however, is used more generally; and, for large works,
when employed as a leader, it is usually confined in a proper tube,
the better to preserve it entire, and to keep it dry. Spunk, made by
soaking certain species of fungus in a solution of saltpetre, takes
fire very readily by the least spark, and, therefore, is used for
collecting and preserving the fire from flint and steel. This spunk,
when well made, and particularly of the proper kind of fungus, may
be cut into slips, and employed advantageously in some fire-works.
In all cases, however, the object is the same, to communicate fire
with facility to the powder, or composition; and this object may be
attained by all those methods, which we have had occasion frequently
to mention. See _Pyrotechnical Sponge_.

To _whiten_ cases is an operation, which merely consists in covering
them with paper, and is performed in the following manner. We procure
as many half-sheets of paper as we have cases, and put them on a
table one upon another. We paste the paper, and roll each case in one
of these sheets, which is named the covering. The paper is cut in
such a manner, that it passes over the end of each case an inch and
a half. There is no particular use in this covering, the case being
made sufficiently strong without it; it makes, however, a handsome
finish. In the Chinese fire-works, their cases are covered with
different coloured papers, and frequently ornamented with gilding. In
all that I have seen, with some of which I have made experiments, the
match of communication is nothing more than twisted match-paper. The
figures are made of paper, painted, and ornamented in the same way;
some resembling animals, &c. but on a small scale. The leaders are
fixed in the usual manner, and the works are fired in the same way.
Tourbillons, serpents, and crackers are chiefly the kind which we
have seen.

_Sec. III. Of Chinese Fire._

The composition for producing this fire, as it is peculiar, and
therefore distinct from all others, was invented by the Chinese, and
hence bears that name. The substance, which produces the peculiar
effect is cast or crude iron. See _Iron_.

It was the brilliant light, produced when iron filings are thrown
into the fire, that gave rise to an improvement in the fire of
rockets, rendering it much more beautiful, than when gunpowder, or
the substances of which it is composed, are alone employed. The
Chinese have long been in possession of a method of rendering fire
brilliant, and variegated in its colours. Cast-iron, reduced to a
powder more or less fine, is called iron-sand, because it answers to
the name given to it by the Chinese. They use old iron pots, which
they pulverize, till the grains are not larger than radish seed; and
these they separate into sizes or numbers, for particular purposes.

It should be observed, that rockets, into the composition of which,
iron-filings and iron-sand enter, cannot be long preserved, owing to
the change which the iron undergoes in consequence of moisture.

It may be proper to introduce here two tables, which exhibit the
proportions of the different ingredients for rockets of this kind
from 12 to 33 lbs.

_For Red Chinese Fire._

-----------+------------+----------+-----------+------------------
Calibers. | Saltpetre. | Sulphur. | Charcoal. | Pulv. cast iron.
| | | | No. 1.
-----------+------------+----------+-----------+------------------
lbs. | lbs. | oz. | oz. | oz. dr.
12 to 15 | 1 | 3 | 4 | 7 0
18 -- 21 | 1 | 3 | 5 | 7 8
24 -- 36 | 1 | 4 | 6 | 8 0
-----------+------------+----------+-----------+------------------

_For White Chinese Fire._

-----------+------------+--------------+-----------+-----------------
Calibers. | Saltpetre. | Meal-powder. | Charcoal. | Pulv. cast iron.
| | | | No. 2.
-----------+------------+--------------+-----------+-----------------
lbs. | lbs. | oz. | oz. dr. | oz. dr.
12 to 15 | 1 | 12 | 7 8 | 11 0
18 -- 21 | 1 | 11 | 8 0 | 11 8
24 -- 36 | 1 | 11 | 8 8 | 12 0
-----------+------------+--------------+-----------+-----------------

These substances are incorporated together in the manner already
stated.

The cast-iron, we observed, is reduced to a fine powder, or rather
_sand_, as the French fire-workers call it, and is then passed
through a sieve. For the method of reducing it to powder, consult
the article on _Iron_. That the brilliancy of the fire is owing
to the iron in its crude state, without being converted into soft
or malleable iron, a process which carries off a large quantity
of carbon, oxygen, &c. and increases its specific gravity,--is
very evident from the effect produced. Wrought iron will occasion
scintillations, somewhat of the same appearance, and steel, also,
in greater abundance; and hence both are employed in sundry
compositions. But the particular character, beauty, and brilliancy
of Chinese fire must be attributed, first to the iron, and secondly
to its peculiar state of combination with carbon and oxygen; for, we
have said, that malleable iron, (which is deprived in a great measure
of these substances in the operation required for its preparation),
produces an effect far inferior to cast iron. This difference
then can only arise from the quality, character, composition, or
properties of these two kinds of iron. Steel, on the contrary, having
a more vivid effect than wrought iron, owes its properties to
another state of combination of the iron and carbon.

Hence we account for the difference in the appearance of the flame,
and consequently the effect, in the different mixtures of crude iron,
malleable iron, and steel. We have already remarked, in treating
of iron, and in explaining the action of bodies in the process of
combustion, in the section on the theory of fire-works, that the
effect of some substances was to produce sparks, stars, &c. In the
present instance, namely, the effect of the composition of the
Chinese fire by combustion, the iron is first ignited by the powerful
heat created by the combustion of the powder, nitre, charcoal, and
sulphur, and in this state, is thrown out with violence, and is
itself consumed. The combustion of iron is nothing more than its
oxidizement, during which a brilliant fire, which characterizes so
pre-eminently the Chinese fire, is produced. This oxidizement of the
metal, in proportion as it is more rapid, necessarily gives rise
to the phenomena of combustion, which, in this, and the generality
of instances, presupposes a combination with oxygen. The fire is,
therefore, more brilliant, as the combustion is more rapid, and
the metal may be oxidized in a greater or lesser degree, but not
to a maximum. From the effect taking place in the air, as it does
not ensue, or is not seen, in the case, it follows, that the iron
receives for the support of its combustion the oxygen of the air.

We have said, that the substances which compose cast-iron, are iron,
carbon, and oxygen, in a peculiar state of combination. We may also
conclude, therefore, that, as carbon, by combustion in oxygen gas,
or in atmospheric air, which contains about twenty-two per cent.
produces carbonic acid, the carbon of the iron during its combustion,
is changed, by its union with oxygen, into this acid. The products,
then, are oxide of iron, and carbonic acid, the latter existing in
the gaseous state. With respect to the other products of combustion,
arising from the gunpowder, saltpetre, sulphur, and charcoal, we have
before noticed them. See _Gunpowder_, and the _General Theory of
Fire-Works_.

We may remark, at the same time, that the intense heat, produced as
well by the combustion of the gunpowder, as by the combustion of
charcoal and sulphur, in contact with the nitrate of potassa, brings
the metal almost to a state of fusion; which, being thrown off in
this state, and considerably divided, is acted upon by the oxygen on
all sides, causing the effect to be uniform and general.

The quantity of iron, it will be seen, which enters into the
different compositions, is various, according to the particular
purpose to which the composition is applied. The _effect_, therefore,
may be varied, as we employ more or less of the iron; and the
state of ignition may be affected, as the proportions of nitre and
charcoal are increased or diminished. These facts are obvious, by
referring to the respective formulæ, and the application of the
several compositions. It is, besides, no less true, that as much
care is required in selecting pure materials for every kind of
artificial fire, as scrupulous accuracy, in following the proportions
prescribed. Nor is this all; the mixture must be intimately made, or
the effect would be doubtful and uncertain.

There is a particular manner required for preparing the composition
of Chinese fire. All the substances must be passed three times
through a sieve, except the sulphur, and the pulverized cast-iron.
These are mixed by themselves, and afterwards with the other
substances. They are turned over frequently with the hand. Cases are
filled with it in the same manner as other compositions.

In order to make the mixture of the sulphur with the iron more
intimate, the latter may be wetted occasionally with spirit of wine,
which should contain no water, as water would tend to rust the
metal, and injure its effect. The sulphur would then mix with more
freedom, and the composition be more perfect. The spirit of wine,
acting merely as a vehicle, afterwards evaporates; and, as it has no
chemical action on either the sulphur or the metal, they would remain
unaltered.

By proceeding in this manner; namely, first mixing the other
substances by themselves, and afterwards the iron and sulphur, and
then the whole, we form an intimate mixture throughout.

The composition, prepared in this way, makes the fire more brilliant;
giving it a greater lustre than by proceeding in a contrary manner.

We are informed, that spontaneous combustion has frequently taken
place, by suffering the iron and alcohol, or spirit of wine, to
remain in contact; and, although this appears an anomaly, which we
will not attempt to explain, yet that it is a fact, and that it has
occurred at Paris, we have the authority of M. Morel.

When the cast-iron is reduced to powder, or _sand_, it is divided
into several sorts, which are proportioned to the caliber employed.
These sorts are marked or numbered, and are used as follows: For
calibers under 7/12ths of an inch in diameter, No. 1; for those of
7/12ths to 10/12ths, No. 2; and for larger calibers, No. 3.

In charging with the composition, care must be taken to turn it
over repeatedly at every other ladle full; because the iron, which
is the heaviest substance, is liable to fall to the bottom. If the
composition be not equally diffused, the fire would be irregular, and
go out by puffs. This is a defect which ought to be guarded against.

The mixture of the composition for _Jessamine_ is made in the same
manner.

Chinese fire, in cases, is commonly employed in garnishing, as it is
called, the circumference of a decoration, or in forming pyramids,
galleries, yew trees, cascades, palm trees, or in short, in producing
a variety of figures, according to taste and fancy. They are often
employed in turning pieces for their last fire, in consequence of the
brilliancy of their effect.

We are told, that nothing is more elegant than Chinese fire; and that
it forms, in its descent, flowers of variegated beauty, which, being
scattered about by the rotation of the piece, resemble the _hydraulic
girandole_ in the rays of the sun.

Chinese fire, however, has little force; and hence, when it is used,
it is accompanied with other fire, as two or more jets of white fire.
The latter is only employed, when the Chinese fire is to be exhibited
on wheels, or turning pieces. When it is on fixed pieces, there is no
occasion for them. Cases of Chinese fire, when burnt alone, will not
turn a wheel.

As the effect of Chinese fire on wheels depends greatly on the
motion of the wheel, its velocity should therefore be accelerated;
which, although the duration of its effect would be shorter and more
brilliant, may be produced by employing several cases of white fire,
and communicating their fire one to the other by leaders in the usual
manner.

There is no doubt, that the accelerated motion of the wheel causes
the composition to burn more rapidly, in the same way as a bellows
excites the heat of a blast-furnace; and, therefore, the increased
brilliancy of the fire may be attributed to the greater rapidity of
the combustion, which necessarily produces, in a shorter time, the
oxidizement of the iron, and, at the same time, the combustion of the
other substances.

With respect to the comparative force of compositions, or that power
by which cases, as rockets, &c. ascend, or which gives motion to
vertical and horizontal wheels, we may observe generally, that these
effects depend on the compositions employed; and that the _recoil_,
in such instances, is proportionate to the impelling power; for the
resistance with which the fire meets from the air, in the immediate
vicinity of the caliber of the case, causes a reaction, which
produces the recoil, and consequently the motion of the wheel. That
this effect depends, in a greater or less degree, on the composition
we use, and the manner the case is charged, is very evident. (See
_General Theory of Fire-Works_. Part 1.)

_Composition of Chinese Fire for calibers under ten-twelfths of an
inch._

Meal-powder, 16 oz.
Saltpetre, 16 --
Sulphur, 4 --
Charcoal, 4 --
Pulverized cast iron, 14 --

_Another of the same._

Meal-powder, 16 oz.
Sulphur, 3 --
Charcoal, 3 --
Pulverized cast iron, 7 --

_Another, for Palm-trees and Cascades._

Saltpetre, 12 oz.
Meal-powder, 16 --
Sulphur, 8 --
Charcoal, 4 --
Pulverized cast iron, 10 --

_Another, white, for calibers of eight and ten-twelfths of an inch._

Saltpetre, 16 oz.
Sulphur, 8 --
Meal-powder, 16 --
Pulverized cast iron, 12 --

_Another, for Gerbes of ten, and eleven-twelfths and one inch
caliber._

Saltpetre, 1 oz.
Sulphur, 1 --
Meal-powder, 8 --
Charcoal, 1 --
Pulverized cast iron, 8 --

It may be proper to remark, that the above formulæ are all approved;
as they have been used in France, and are given on the authority of
Morel and Bigot. We are informed, indeed, that these proportions
produce the most perfect fire, which surpasses the fire of the
Chinese. From the many experiments made in France, instituted with
the view of determining the best proportions, and leading, in fact,
to the improvement of the original composition, we do not hesitate to
give them the preference over all others.

In the composition of wheel-cases, Chinese fire is sometimes used,
and then only for decoration; but in nearly all the compositions
employed, in wheel-works, for standing or fixed cases, sun-cases, &c.
steel-dust forms a constituent part. The proportion it bears to other
substances is various: _viz._ to meal-powder, as one to five, one to
ten, &c. In one of the formulæ for brilliant fire, the proportion
is still greater, and in another less; but by mixing seven and a
half ounces of steel-dust with meal-powder, saltpetre, and sulphur
in the proportion of eleven pounds, one pound two ounces, and four
ounces respectively, a composition is formed, calculated to produce a
brilliant fire. But as this subject will be considered, when we treat
of wheel-works, standing pieces, &c. and the different compositions
appertaining thereto, we would only observe, that Chinese fire should
always be preferred, where the object is decidedly appearance, with
brilliancy and splendour.

_Sec. IV. Of Bengal Lights._

We have had occasion to mention heretofore, that metallic as well as
the crude, or sulphuret of, antimony, entered as a component part
into some compositions, in order to vary the effect and appearance
of the flame. That this is the effect, in the composition, which
constitutes the Bengal lights, is a fact well known, and to which its
particular character is owing.

Bengal lights, in consequence of the whiteness and brilliancy of
their flame, are considered as highly important in fire-works. The
composition was a long time kept secret, and artists were at a loss
to compound it, for those who possessed the secret, it appears,
would not divulge it. Simple as it is, it was not known, until many
experiments were made, which proved its identity with the original
Bengal composition; and, since that time, it has been confirmed by
the original formula. Morel assures us, that he purchased the secret.

_Composition of Bengal Lights._

Saltpetre, 3 lbs.
Sulphur, 13 oz. 4 dr.
Antimony, 7 oz. 4 dr.

They are pulverized and mixed in the usual manner, and passed three
times through a hair sieve. Any quantity may be made at one time. The
composition is usually put in earthen vessels, without decorations.
They may be of different sizes, and, in fact, as broad as they are
high, sufficiently large, however, to contain the composition. A
small quantity of dry meal-powder is scattered over its surface, and
a sheet of paper is tied on to secure it. It is primed with port fire
match.

The _effect_ of this mixture is evidently that of the combustion
of the sulphuret of antimony, as well as of the sulphur. The nitre
furnishes the oxygen to both, and, as the combustion is rapid, the
metal is oxidized, probably forming the antimonic acid, as the
antimony may be oxidized to the maximum. There is another view, in
which this combustion may be considered. According to the present
theory of the formation of sulphuric acid, by the combustion of
sulphur, and nitre in leaden chambers, it appears, that sulphurous
acid is first produced, and nitric oxide gas, (deutoxide of azote),
is also formed; and that the latter by uniting with the oxygen of the
air is changed into nitrous acid, which is _then_ acted upon by the
sulphurous acid, and is decomposed. Part of its oxygen combines with
the sulphurous acid, changing it into the sulphuric, and deutoxide of
azote is reproduced. In all probability, then, in the combustion of
the composition of Bengal lights, the nitric oxide itself may affect
the combustion of the antimony, which, as it would be enveloped
in nitrous acid vapour, arising from the union of nitrous gas and
oxygen, may present, in a measure, one of those cases of combustion,
in which nitric oxide acts as a supporter, affording on that account
a particular phenomenon. Reasoning _a posteriori_, this may be
affected again by the formation of sulphuric acid; for a part of the
sulphurous acid may be changed into sulphuric, not by its immediate
union with the oxygen of the nitre, according to the old theory, but
by the decomposition of the vapour of nitrous acid. This conclusion,
however, is sufficient, that the nitre is decomposed, and during its
decomposition, the sulphur and antimony are brought into action; that
a large quantity of caloric and light is evolved, whether from the
oxygen gas of the atmosphere, or the substances themselves we will
not stop to inquire; and, that, in the act of combustion, the sulphur
and antimony are acidified, forming new products.

It will be seen, by examining the formulæ for the composition of
the white and blue-lances, that they both contain antimony, but in
different proportions: thus, in the white lance, the proportion
of antimony is as one to eight of sulphur, as one to sixteen of
saltpetre, and as one to four of meal-powder; and in the blue-lance,
as it is composed only of saltpetre and antimony, the proportion of
the latter to the former is as eight to sixteen. In the composition
of Italian roses, or fixed stars, the proportion of antimony is
still smaller, and is as one to ten of sulphur, one to sixteen of
saltpetre, and one to twelve of meal-powder. Now, by comparing these
proportions with those which constitute the Bengal light composition,
they will be found to differ from those compositions, into which the
same substances enter; for, in the Bengal lights, the proportion of
the antimony to the sulphur is as five to nine, and to the saltpetre,
as five to thirty-two, or thereabout.

The inference we draw, therefore, is, that the white lance
composition differs from the blue, in containing meal-powder and
sulphur, and the latter from the former, in containing no sulphur,
but eight times as much antimony; that the white-lance composition
varies from the Bengal light, by containing one-half less of
saltpetre, one-fifth less of antimony, and one-ninth less of
sulphur; and that the Bengal composition differs from the blue lance
composition, in having double the quantity of saltpetre, nine parts
of sulphur, (the blue-light having none,) and nearly one-third less
of antimony. If we attend to these proportions of the antimony, with
the other ingredients, in the respective preparations, we will find,
that the difference, in the proportions of the antimony, produces,
with the presence or absence of the meal-powder and sulphur, and
the difference also in the quantity of the latter, the phenomena
or effects which characterise them. It is thus, therefore, with
this, as with other preparations; only vary the proportions, and
institute new equivalents, as it were, in any particular preparation,
and adopt some and reject other substances, and the effects are
varied agreeably thereto; and, if improvements are to be made in
any composition, they can only be effected by experiment, and the
investigation of the effects of new proportions, a comparison of
which, with the effect of any particular composition, prepared
according to a given formula, can alone determine the relative value
of any new formula.

_Sec. V. Of Roman Candles._

Roman candles are formed on a roller seven-twelfths of an inch in
diameter, and are generally fifteen inches in length. They are
choaked at one end, and tied in the usual manner. According to the
nature of the charge, which we shall mention, their effect is to
throw out brilliant stars, to the height of one hundred and more
feet, and when arranged with marrons, they finish with a report.

After the cases are formed, and ready to be filled, the operation is
performed with expedition, by tying a number of them together, and
charging them in that manner. The cases are charged with the rocket
composition, heretofore described, in the following way: A ladleful
of composition is put in, and rammed, using seven or eight blows with
the mallet; a small spoonful of powder is then added, and afterwards
a moulded star. This star should fit the caliber of the case. More
of the composition is then added, then meal-powder, and afterwards
a star, and these are repeated in the same order, till the case is
completely charged. Care must be taken in observing this order,
otherwise the effect would be destroyed. In striking with the mallet,
attention must also be paid, that the blows are not too violent, or
the star might be destroyed. When the cases, or candles, are charged,
we untie them, and roll some coarse paper round each end of them, at
the extremity, and round the choak.

We may remark, that in the charging of Roman candles, as their effect
depends greatly on the appearance of the stars, which issue out in
succession, too much care cannot be used in preserving the star
composition entire. To do this, much art is required in putting in,
and ramming, the rocket composition, so as not to injure or break
it. The quantity of gunpowder to each star must be small, otherwise
it might burst the case. Roman candles may be fired singly or
several at a time, according to the effect required. To fire one in
a chandelier, for instance, it is only necessary to prime it with
priming paste; but, if we wish to form batteries in an artificial
fire-work, in order to produce a variety, or to mount them on fixed
or moveable pieces, we may, if necessary, terminate their effect with
marrons, which may be effected by uniting them in such a way as to
make the fire of the one, at a given time, communicate to the other.
This communication is usually made through the choak, by attaching a
match, which is carried to the mouth of the marron; so that, when the
candle has burnt out, the last portion of the fire may pass to the
marron, the effect of which is instantaneous. If necessary, priming
paste may be used to facilitate the communication of the fire. The
marron may be fixed directly under the bottom of the candle, by
making the whole solid by a paper cylinder, which fits over the ends
of both.

The mosaic candles, as well as mosaic simples, are formed in cases
of the same thickness as sky-rockets, from which they differ in the
introduction of stars along with the composition. We may remark,
also, that they are rolled without pasting; and although Morel
recommends choaking the cases, yet a writer of more recent date, M.
Bigot, whose practical knowledge must be great, recommends _plugging_
them on the stick or roller. This is done by merely turning the end
down about half an inch, and then beating it. Before the composition
is added, he advises, also, the introduction of two or three fingers'
thickness of clay, which is rammed very solid. This answers for a
base, and supersedes the necessity of choaking. If, as we before
remarked, it is necessary to communicate fire from this end to a
marron or any other case, the clay must be bored to the composition,
and quickmatch inserted; or, instead of this, the case itself, above
the clay, may be perforated, and a communication in this way made.

Besides the ordinary Roman candles, intended expressly for
exhibition, there is another preparation, which goes under the name
of the incendiary Roman candle, used for the purposes of war. This
preparation is composed of three parts of sulphur, four parts of
saltpetre, one part of antimony, and half a part of meal-powder; but
this, together with the incendiary stars, we purpose to consider when
we treat of _Military Fire-works_.

_Sec. VI. Of Mosaic Simples._

Mosaic simples are in reality nothing more than a variety of the
Roman candle, being formed in the same manner, and of the same
composition, except that the moulded stars are different, and
produce another effect. The mosaic simples produce merely a tail,
or spout of fire; whereas the Roman candle throws out a brilliant
star. They may be used with marrons in the same manner as the Roman
candle. The length of the case is fifteen inches, and seven-twelfths
of an inch in diameter. Mosaic simples are very appropriate to
terminate a piece. A number of cases may be used by placing them
in such a manner, that their fires may cross each other, an effect
more striking than the ordinary mode of exhibition. This may be
accomplished by arranging them, two and two, to a horizontal stick,
observing that their mouths are up, and that they cross each other.
They are lashed to the stick, and leaders are carried from the mouth
of one to the mouth of another. This communication is so managed,
that two pieces discharge at the same time. They may be employed in a
variety of ways, according to fancy.

Sometimes pyramids forty or fifty feet high are furnished on each
side, with cases of mosaic simples, with a star at the summit, and
white and coloured lances differently dispersed.

The curtain of fire, produced by so many cases, the height to
which it rises, the appearance of the star with the variegated and
diversified effect of the coloured lances, all contribute to the
splendour of this arrangement.

_Composition of the Mosaic Moulded Stars._

Saltpetre, 4 oz.
Sulphur, 4 dr.
Meal-powder, 16 oz.
Charcoal, 3 --

Or in proportional parts: saltpetre, four parts; sulphur, half a
part; meal-powder, sixteen parts; and charcoal, three parts.

These substances, being finely pulverized, and intimately mixed in
the usual manner, are combined with gum-water, &c. as directed for
preparing _stars_, and cut into lozenges, which are then rolled in
priming powder, and dried in the shade.

_Sec. VII. Of Mosaic Tourbillons._

We may merely remark, as we have mentioned tourbillons heretofore,
that the cases for the mosaic tourbillons, by which name they are
designated, are seven inches in length, five-twelfths of an inch in
interior diameter, and nine-twelfths in exterior diameter; and that
the composition with which they are charged, is composed of sixteen
parts of meal-powder, and three and a half parts of pulverized
charcoal. See _Tourbillon_.

_Sec. VIII. Of Hydrogen Gas in Fire-Works._

M. Diller, some years since, exhibited at the pantheon of Paris,
artificial fire produced by the combustion of hydrogen gas. From
the short account we have of this exhibition in the _Dictionnaire
de l'Industrie_, vol. iii, p. 39, it seems, that he employed three
different airs, or gases, and produced three different flames:
viz. white, blue, and green, which were made by the mixture of the
three gases; and that he represented very perfectly, suns, stars,
triangles, the cross of Malta, and sundry figures of animals in
motion.

We may remark, that, if hydrogen gas be pure, the flame is of a
yellowish-white; but this, however, is seldom the case, as the gas is
always more or less impure, and, according to the substances it may
hold in solution, so is the flame tinged. It is most usually reddish,
because the gas holds in solution a little charcoal. In Cartwright's
fire, ether is always mixed with the whole, or a _part_ of the gas,
which is brought to the state of vapour by the application of a
gentle heat, or even by immersing the bladder of gas, which contains
the liquid ether, in hot water.

When combined with arsenic, in the form of arsenuretted hydrogen
gas, hydrogen burns with a blue flame; combined with phosphorus it
takes fire spontaneously, producing a white flame with a beautiful
corona, caused by the formation of water; and when combined with
sulphur, forming sulphuretted hydrogen or hepatic gas, it burns with
a bluish-red flame, and a quantity of sulphur is deposited. Various
mixtures of hydrogen with other gases, in due proportions, will
produce different coloured flames; so that, by paying attention to
this circumstance, the same variety of appearances may be produced,
as in Diller's exhibition.

Bladders, (or sacks made of oiled silk, which are preferable), when
filled with gas, and connected with tubes, revolving jets, &c. bent
in different directions, and formed into various figures, and pierced
with holes of different sizes, will, when pressure is applied, allow
the gas to pass through the different tubes, jets, &c. which, when
inflamed, will represent the sun and stars. If to this be added,
triangular tubes, tubes in the form of the cross of Malta, or any
other figure, they being pierced in their sides with a great number
of holes not larger than the point of a pin; it is obvious, that
fixed pieces may be represented, as well as revolving ones. In this
manner, Diller must have made his exhibition.

Hydrogen gas is usually made, by pouring on zinc, or iron filings,
in a gas bottle, sulphuric acid diluted with six times its weight of
water. The latter is decomposed; its oxygen unites with the metal,
and while the oxide is taken up by the acid, the hydrogen passes off
in the form of gas. The gas may be received directly in the bladder
or bag.

The _inflammable air pistol_ is nothing more than a hollow metallic
cylinder, or an instrument in the shape of two cones joined base to
base, and furnished with a touch-hole, and handle. This pistol is
filled with a mixture of hydrogen and oxygen gases, or in lieu of the
latter, atmospheric air; a plug or stopper is put in the caliber,
and, when the touch-hole is brought in contact with a lighted taper,
an explosion will take place, and the plug be sent out with much
force. The same effect may be shown by passing the electric spark
over the touch-hole, and hence, on an insulated stool, a person,
charged with electricity, may set it off by the finger or nose. This
pistol is usually called the Voltaic pistol, from Volta, who is said
to have invented it.

M. Biot (_Traité de Physique Experimentale_, &c. tome ii, p. 435)
describes the Voltaic pistol as a metallic vessel of a spheroid
shape, furnished with an aperture and pipe, and with a conductor for
the electric fluid, which passes through the middle of the vessel.
This conductor is insulated, as it goes through a glass tube, and
extends to within an eighth of an inch of the middle; and directly
opposite to this conductor is a metallic wire, having, like the first
conductor, a small metallic ball on its end. This conductor is placed
a short distance from the first; so that, when the electric fluid is
conducted, it passes from one ball to the other within the pistol,
and hence inflames the hydrogen gas. With respect to the form of
the pistol, it is of no moment whether it be cylindrical, conical,
or globular, as the effect is the same, provided that it contain a
sufficient quantity of gas, and the spark is conveyed through the
gas, or the gas is inflamed by a vent. The air pistol described
by Brande (_Brande's Chemistry_) is cylindrical, or rather in the
shape of a cannon, and, where the touch-hole should be, there is an
insulated conductor, which conveys the spark to the interior.

The _Voltaic lamp_ is also a contrivance by which hydrogen gas
is inflamed by the electric spark, which sets fire to a taper.
The original lamp has been greatly improved, and simplified. The
eudiometer of Volta is another contrivance by which hydrogen gas is
burnt, in a strong tube, by the electric spark.

The detonation of inflammable air may be shown over a pneumatic
tub, by filling metallic gas-holders with a mixture of hydrogen
gas and atmospheric air. When flame is brought in contact with the
mouth of the gas-holder, an explosion will immediately take place.
Soap-bubbles, blown with hydrogen gas, mixed with atmospheric air,
will take fire, on presenting a lighted taper, and give a slight
explosion. The ascension of these bubbles demonstrates, that the gas
is lighter than atmospheric air, and it is its extreme levity that
fits it for the purpose of filling balloons. It may be made twelve
times specifically lighter than atmospheric air, by passing it over
dry muriate of lime, in order to absorb the moisture it may contain,
provided the gas be free from carbon, or carbonic acid.

Light carburetted hydrogen gas, or _fire-damp_ of miners, is that
gas, which so often formerly produced many dreadful accidents by its
explosion. The invention, by Sir H. Davy, of the safety-lamp prevents
this effect.

The principle of this most valuable discovery, appears to be
altogether in the fine metallic gauze case, which surrounds the
flame of the lamp; so that, as it is found by numerous and repeated
experiments, the inflammable air, if present, cannot take fire
outside of the gauze; in other words, the flame, in the interior of
the case, is prevented from setting fire to the exterior atmosphere,
however explosive it may be.

Hydrogen gas, in combination with carbon, is not only generated
in mines and coal pits, (in the latter of which, it is the most
abundant), but is frequently found on the surface of springs in the
form of bubbles, usually however combined with sulphur; and in many
places on the surface of the earth. It may be inflamed by a candle.
The burning springs consist of this gas which is set on fire, and
the combustion is kept up by a constant supply of gas from the same
source. In the East, this gas is very often conveyed under ground
through hollow reeds, and is constantly kept burning. At other times,
it is conveyed to the sacred temples, as with the Zoroasters, and
burnt as _holy fire_; and in some countries, it is so abundant,
that the natives employ it as fuel for boiling their pots. It is
found in different parts of the United States. A striking incident,
showing its effects, occurred lately near Cincinnati, in the state
of Ohio. It appears, that, in making an excavation, and boring for
salt water, the workmen penetrated their augur into a cavity, which
contained an abundance of gas, and which, with the water, made its
way to the excavation. Not suspecting that the gas was inflammable,
or being unacquainted with it, and apprehending no danger, they
brought a lighted taper; and the gas, being mixed with atmospheric
air, exploded with a noise so considerable, that it was heard several
miles in the neighbourhood. The men were much burnt, some of them
dangerously.

The gas was afterwards inflamed by applying a taper, as it rose in
bubbles from the surface of the water.

The philosophical candle is nothing more than hydrogen gas set on
fire as it proceeds from a capillary tube, being formed in a bottle
to which the tube is attached. The most brilliant flame, however, is
produced by hydroguret of carbon, or olefiant gas.

Inflammable air is often generated in the stomachs of dead persons,
for, on applying a lighted candle, the _vapour_ has been known to
take fire. Dr. Swediaur relates some instances of the same kind, but
in living persons, in which the _urine_ of the by standers was made
use of. According to several authorities, combustion has been known
to take place spontaneously in living persons. Lair, however, is of
opinion, that, in these cases, it must have occurred by some slight
external cause, such as the fire of a candle, taper, or pipe. There
can be no question as to the developement of hydrogen gas.

Morse, (_Universal Geography_, article Persia, p. 588), after
mentioning the Persian _guebres_, the disciples and successors of the
ancient magi, and followers of Zoroaster, speaks of a combustible
ground about ten miles distant from Baku, a city in the north of
Persia, as the place for their devotion. This ground contains several
old temples, and is remarkable for the quantity of inflammable
air it emits, which is employed to produce the _sacred flame of
universal fire_. If the ground be penetrated with a stick, there will
issue out such a prodigious quantity of inflammable air, as, when
lighted, will burn for a considerable time. This gas, we remarked, is
employed there for lighting, cooking, and other purposes. The naphtha
districts, in Persia, furnish this gas in abundance. See _Naphtha_.

A Sandusky (Ohio) paper states, that, about one mile and a quarter
from Milan, is a place just in the edge of the water of Huron river,
where there is a current of inflammable gas, that burns with a clear
bright blaze, and is in sufficient quantity to light ten houses.

CHAPTER X.

OF THE MANNER OF FIXING AND ARRANGING FIRE-WORKS IN GENERAL FOR
EXHIBITION.

Having already treated of the formation of various kinds of
fire-works, we come now to consider their arrangement in fixed and
moveable pieces.

It is obvious, that the order of arrangement, the manner of disposing
the work, or establishing pieces for exhibition, may be greatly
varied according to taste and fancy. The great variety of fixed and
moveable pieces, consisting of suns, moons, stars, &c. which may be
either made permanent, or to revolve on, or round a centre; or of
wheels, double, single, or treble, either moving round other wheels,
or by themselves in a vertical or horizontal order, together with
the arrangement of fire-pots, and coloured lights, the management
of rockets, the formation of aerial stars, serpents, tourbillons,
&c. and the imitation of cascades, girandoles, and water-falls, all
depend on the taste and fancy of the artist.

It is our intention, therefore, in the different sections of this
chapter, to give the order and arrangement of pieces, as adopted in
Europe, and particularly in France; so that the manner of fixing any
one piece, or combination of pieces, to produce effects of different
kinds, may be seen at one view. The moveable pieces are generally
made of wheel-work, the wheel always turning upon an axle, which may
pass entirely through and be kept on by a nut or pin. They should
revolve without much friction, and, for this reason, the spindle
should be of metal, and oiled or greased. Black lead, along with
tallow, will diminish the friction very considerably. As to the
formation of the wheel, whether it be solid, or formed of spokes
and a band or hoop, or made with several concentric bands, placed
at given distances apart, &c. the observations on this head will be
found under the respective articles, and, generally, on all other
pieces for exhibition.

We purpose, in a subsequent chapter, to notice particularly
the works, made in and on water, usually denominated _aquatic
fire-works_; as their arrangement, in many respects, differs from
those on the land. Aquatic works furnish a variety, both in character
and effect, and, therefore, are calculated to produce, in conjunction
with land works, a brilliant spectacle. Of this, we have an instance,
mentioned in the introduction to this part of our work, in the
splendid exhibition at the _Pont Neuf_ in Paris.

_Sec. I. Of the Composition of Wheel-Cases, standing and fixed._

It may not be improper, before noticing the arrangement of
wheel-cases, to give in this place the compositions, which are
used for charging them, reserving, however, the notice of some
preparations, when we treat of such works, in which they are
particularly employed.

_Wheel-cases from two ounces to four pounds._

1. Meal-powder, 2 lbs.
Saltpetre, 4 oz.
Iron-filings, 7 --

2. Meal-powder, 2 lbs.
Saltpetre, 12 oz.
Sulphur, 4 --
Steel-dust, 3 --

3. Meal-powder, 4 lbs.
Saltpetre, 1 --
Sulphur, 8 oz.
Charcoal, 4½ --

4. Meal-powder, 8 oz.
Saltpetre, 4 --
Sawdust, 1½ --
Sea-coal, ¾ --

5. Meal powder, 1 lb. 4 oz.
Sulphur, 4 -- 10 dr.
Saltpetre, 8 --
Glass-dust, 2½ --

6. Meal-powder, 12 oz.
Charcoal, 1 --
Sawdust, ½ --

7. Saltpetre, 1 lb. 9 oz.
Sulphur, 4 --
Charcoal, 4½ --

8. Meal-powder, 2 lbs.
Saltpetre, 1 --
Sulphur, ½ --
Sea-coal, 2 oz.

9. Saltpetre, 2 lbs.
Sulphur, 1 --
Meal-powder, 4 --
Glass-dust, 4 oz.

10. Meal-powder, 1 lb.
Saltpetre, 2 oz.
Steel-dust, 3½ --

11. Meal-powder, 2 lbs.
Steel-dust 2½ oz.
Beat iron, 2½ --

12. Saltpetre, 2 lbs. 13 oz.
Sulphur 8 --
Charcoal, 4 --

_Slow fire for wheels._

1. Saltpetre, 4 oz.
Sulphur, 2 --
Meal-powder, 1½ --

2. Saltpetre, 4 oz.
Sulphur, 1 --
Antimony, 1 -- 6 dr.

3. Saltpetre 4½ oz.
Sulphur, 1 --
Meal-powder, 1½ --

_Dead fire for wheels._

1. Saltpetre, 1¼ oz.
Sulphur, ¼ --
Lapis calaminaris, (prepared calamine,) ¼ --
Antimony, 2 dr.

_Standing, or fixed cases._

1. Meal-powder, 4 lbs.
Saltpetre, 2 lbs.
Sulphur and charcoal, (together,) 1 --

2. Meal-powder, 2 lbs.
Saltpetre, 1 --
Steel-dust, 8 oz.

3. Meal-powder, 1 lb. 4 oz.
Charcoal, 4 oz.

4. Meal-powder, 1 lb.
Steel-dust, 4 oz.

5. Meal-powder, 2½ lbs.
Sulphur, 4 oz.
Seacoal, 6 --

6. Meal-powder, 3 lbs.
Charcoal, 5 oz.
Sawdust, 1½ --

_Sun cases._

1. Meal-powder, 8½ lbs.
Saltpetre, 1 -- 2 oz.
Steel-dust, 2 -- 10 --
Sulphur, 4 --

2. Meal-powder, 3 lbs.
Saltpetre, 6 oz.
Steel-dust, 7½ --

_Crowns or globes._

1. Saltpetre, 6 oz.
Sulphur, 2 lbs.
Antimony, 4 oz.
Camphor, 2 --

This view of the compositions used in fixed and turning pieces,
exhibits the various compounds which _have been_ employed, and,
therefore, may be relied upon. Notwithstanding they are considered
the standard formulæ; yet we must observe, that in some, particularly
in the turning sun, with variations, changes are required, in order
to produce a variety in the effect. This is accomplished, by making,
in the first place, a particular composition, and mixing a given
quantity of it with meal-powder, which forms the second change.
Of this second composition, combined in a given proportion, with
meal-powder, we form a third change; and, in like manner, we employ
the third along with more powder, to form a fourth, and the fourth to
form a fifth. The particular manner of making these changes will be
described in a future section.

_Sec. II. Of Single, Vertical, Horizontal, Spiral, and other wheels._

Of the different kinds of _vertical wheels_, we may mention, that
some have their fells of a circular form, others, in the form of
a hexagon, octagon, or of a figure of a greater number of sides,
according to the length of the cases designed for the wheels. The
spokes being fixed in the nave, nail slips of tin, with their edges
turned up, so as to form grooves for the cases to lie in, from the
end of one spoke to another. Then tie the cases in the grooves head
to tail, in the same manner as those on the horizontal water-wheel;
so that the cases successively taking fire from one to another,
will keep the wheel in an equal rotation. Two of these wheels are
very often fired together, one on each side of a building, and both
lighted at the same time, and all the cases filled alike to make
them keep time together. This may be accomplished in the following
manner. In all the cases of both wheels, except the first, and on
each wheel, drive two or three ladles full of slow fire, in any part
of the cases, but be careful to ram the same quantity in each case;
and in the end of one of the cases on each wheel, one ladle full
of dead-fire composition, which must be very lightly driven. Many
charges of fire may be made by the same method.

The hole in the nave of the wheel may be lined with brass, and made
to turn on a smooth iron spindle. On the end of this spindle, let
there be a nut to screw off and on. When we have placed the wheel on
the spindle, screw on the nut, which will keep the wheel from flying
off. Let the mouth of the first case be a little raised.

Vertical wheels are made from ten inches, to three feet in diameter,
and the size of the cases must vary accordingly. Four-ounce cases
will be sufficient for wheels of fourteen or sixteen inches in
diameter, which is the proportion generally used. The best wood for
wheels of all kinds, is the light and dry beech.

_Horizontal wheels_ are more perfect, when their fells are made
circular. In the middle of the top of the nave must be a pintle,
turned out of the same piece as the nave, two inches long, and equal
in diameter to the bore of one of the cases of the wheel. There must
be a hole bored up the centre of the nave, within half an inch of
the top of the pintle. Nail at the end of each spoke, of which there
should be six or eight, a piece of wood with a groove, cut in it to
receive the case. Fix these pieces in such a manner, that half the
cases may incline upwards, and half downwards, and that, when they
are tied on, their heads and tails, or extremities, may come very
near together. From the tail of one case to the mouth of the other,
carry a leader, which is necessary to be secured with pasted paper.
Besides these pipes, a little meal-powder must be placed in the
inside of the pasted paper, to blow off the pipe, that there may be
no obstruction to the fire from the cases. By means of these pipes,
the cases will successively take fire, burning one upwards, and the
other downwards. On the pintle, fix a case of the same sort as those
on the wheel. This case must be fired by a leader from the mouth of
the last case on the wheel, which case must play downwards. Instead
of a common case in the middle, we may put a case of Chinese fire,
sufficiently long to burn a given time, or as long as two or three
cases on the wheel.

Horizontal wheels are often fired two at a time, and made to keep
time, like vertical wheels, only they are prepared without any
slow or dead-fire. Ten or twelve inches will be sufficient for the
diameter of wheels with six spokes.

With respect to _spiral wheels_, we may remark, that they are only
double horizontal wheels, made in the following manner: The nave
must be thicker than that of the single sort; and, instead of the
pintle at top, a hole is usually made for the case to be fixed in.
There are two sets of spokes, one set put near the top of the nave,
and the other, near the bottom. At the end of each spoke, cut a
groove, in which the cases are to be tied, there being no fell. The
spokes should not be more than three and a half inches long from the
nave, so that the wheel may not be more than eight or nine inches
in diameter. The cases are placed in such a manner, that those at
top play down, and those at the bottom play up; but let the third or
fourth case burn horizontally. The case in the middle may begin with
any of the others. Six spokes will be sufficient for each set; so
that the wheel may consist of twelve cases, besides that on the top;
the cases six inches each.

_Plural wheels_ are different from the former. They are made to turn
horizontally, and consist of three sets of spokes, placed six at top,
six at bottom, and four in the middle, which must be a little shorter
than the rest. Let the diameter of the wheel be ten inches. The cases
must be tied on the ends of the spokes, in grooves, cut on purpose,
or in pieces of wood, nailed on the ends of the spokes, with grooves
cut in them as usual. In clothing these wheels, make the upper set
of cases play obliquely downwards, the bottom set obliquely upwards,
and the middle set, horizontally. In placing the leaders, we must
so arrange them, as that the case may turn thus: namely, first up,
then down, then horizontally, and so on with the rest. But another
change may be made, by driving in the end of the eighth case two or
three ladles full of slow fire, to burn till the wheel has stopt its
course. Then let the other cases be fixed the contrary way, which
will make the wheel run back again. For the case at top, we may put
a small gerbe, and the cases on the spokes may be short, and filled
with the strong brilliant charge.

For forming the _illuminated spiral wheel_, we must proceed thus:
First have a circular horizontal wheel, made two feet in diameter,
with a hole quite through the nave; then take three thin pieces of
light board, three feet long each, and three-fourths of an inch
broad. One end of each of these pieces, nail to the fell of the
wheel, at an equal distance from one another; and the other end, nail
to a block with a hole in its bottom, which must be perpendicular
to that in the block of the wheel, but not so large. Plane a hoop
down very thin and flat, and nail one end of it to the end of the
wheel, and wind it round three sticks in a spiral line, from the
wheel to the block at top. On the top of this block, fix a case of
Chinese fire. On the wheel may be placed any number of cases, which
must incline downwards, and burn two at a time. If the wheel should
consist of ten cases, we may let the illuminations and Chinese fire
begin with the second cases. The spindle for this wheel must be a
little longer than the cone, and made very smooth at top, on which
the upper block is to turn, and the whole weight of the wheel to rest.

For making the _double spiral wheel_, the block, or nave, must be as
long as the height of the worms, or spiral lines; but must be very
thin, and as light as possible. In this block fix several spokes,
which must diminish in length from the wheel to the top, so as not to
exceed the surface of a cone of the same height. To the ends of these
spokes nail the worms, which must cross each other, several times.
These worms clothe with the same illuminations as those on the
single wheels, but the horizontal wheel may be clothed according to
fancy. At the top of the worm, place a case of slow fire, or an amber
light.

_Balloon wheels_ turn horizontally. They are usually made two feet
in diameter without any spokes, and very strong, with any number
of sides. On the top of the wheel, range and fix in pots of three
inches in diameter, and seven inches high each, as many as there
are cases on the wheel. Near the bottom of each pot, make a small
vent; and into each of these vents, carry a leader from the tail of
each case. Some of the pots may be charged with stars and some with
serpents, crackers, &c. As the wheels turn, the pots will be fired in
succession, and throw into the air a great variety of fires.

_Fruiloni wheels_ are made with a nave, nine inches long, and three
inches in diameter. Near the bottom of this nave, fix eight spokes
with a hole in the end of each, sufficiently large to receive a two
or four-ounce case. Each of these spokes may be fourteen inches long
from the block. Near the top of this block, fix three more of the
same spokes, exactly over the others, but not so long by two inches.
As this wheel is to run horizontally, all the cases in the spokes,
must play obliquely upwards, and all those in the spokes at bottom,
obliquely downwards. This being accomplished, have a small horizontal
wheel, made with eight spokes, each five inches long from the block.
On the top of this wheel, place a case of brilliant fire. All the
cases on this wheel must play in an oblique direction downwards, and
burn two at a time; and those on the large wheel, four at a time; i.
e. two of those on the top set of spokes, and two of those in the
bottom set of spokes.

The four first cases on the large wheel, and the two first on the
small, must be fired at the same time, and the brilliant fire at the
top, at the beginning of the last cases. The cases of the wheels may
be filled with a gray charge. When these wheels are completed, we
must have a strong iron spindle, four feet six inches long; and fixed
perpendicularly on the top of a stand. On this, we put the large
wheel, whose nave must have a hole quite through from the bottom to
the top. This hole must be large enough to turn easy round the bottom
of the spindle, at which place there must be a shoulder, to keep the
wheel from touching the stand. At the top of the spindle, put the
small wheel, and join it to a large one with a leader, in order that
they may be fired both together.

_Pin wheels_, as they are called, are formed by rolling some paper
into pipes of about fourteen inches in length. The paper should be
thin, and rolled of three thicknesses. When they are thoroughly
dried, procure a tin tube, twelve inches long, to fit easy into the
pipes. At one end of this tube, fix a small conical cup, which cone
is called a funnel; then bend one end of one of the pipes, and put
the funnel in at the other, as far as it will reach, and fill the
cup with composition. Draw out the funnel gently, shaking it up and
down, and it will fill the pipe, as it comes out. Having filled some
pipes, procure some small blocks, about one inch in diameter and half
an inch thick. Round one of these blocks, wind and paste a pipe, and
to the end of this pipe, join another, which must be done by twisting
the end of one pipe to a point, and putting it into the end of the
other with a little paste. In this manner, join four or five pipes,
winding them one upon another, so as to form a spiral line. Having
wound on the pipes, paste two strips of paper across them to hold
them together. The pipes must also be pasted together.

The other method of making these wheels is described thus: wind on
the pipes without paste, and stick them together with sealing wax
at every half turn; so that, when they are fired, the end will fall
loose, every time the fire passes the wax, by which means the circle
of fire will be considerably increased.

The formers for these pipes are made from 1-1/2 to 4/16ths of an inch
in diameter. They may be fired on a large pin, and held in the hand
with safety.

_Composition for Pin-Wheels._

Meal-powder, 8 oz.
Saltpetre, 2 --
Sulphur, 1 --
Steel-filings, or the powder of cast-iron, ¼ --

The ingredients are to be well mixed, and dry. The mixture need not
be very fine, or it will adhere to the funnel.

_Sec. III. Of Revolving Suns._

From what has been said in the preceding section, it is obvious, that
revolving or turning suns may be formed, or any piece put in motion,
in the manner already described. The most common mode of forming
a sun, is to attach to three naves, which proceed from a hub, that
revolves on a spindle, from three to six cases, placing them in such
a way, that they may be fired successively. The jets, or spouts,
proceeding from the cases, constitute the _rays_, the sun being in
the centre, which revolves with the cases on an axis. The arrangement
of these cases should be such, as that the six (as that number is
usually employed,) might form the perimeter.

The cases may be charged with one, or with different compositions,
given in the following table. They are attached in such a way, that
the head of the first is nearly in contact with the _ray_ of the
second, and that to the third, &c. When the first case is finishing,
it must, therefore, communicate fire to the second, that to the
third, and so on in succession. These cases must be attached firmly
by wire; and leaders are used to communicate the fire, as in other
works. The end must be enclosed in the neck of the first case, and
the other end in that of the second, &c. They are secured in their
respective positions, by tying them securely to the cases.

With respect to the composition employed, it may be varied according
to pleasure. In most instances, however, the ordinary sun-composition
is used; but, in other instances, this is varied according to
circumstances. Morel has adopted the following composition for a sun
of six cases, the cases being eight-twelfths of an inch in diameter.
These cases are mounted on the arms of the sun in the same manner as
before described.

_Composition for a sun with variations, the cases of which are
eight-twelfths of an inch in caliber._

_No. 1, first change,_

Saltpetre, 16 oz.
Sulphur, 6 --
Meal-powder, 3 --

_No. 2, second change,_

Composition No. 1, 2 oz.
Meal-powder, 2 --

_No. 3, third change,_

Composition No. 2, 1 oz.
Meal-powder, 1 --

_No. 4, fourth change,_

Composition No. 3, 1 oz.
Meal-powder, 1 --

_No. 5, fifth change,_

Composition No. 4, 1 oz.
Meal-powder, 1 --

_No. 6, sixth change,_

Meal-powder alone, for two changes.

It appears evident, that the changes thus produced are owing to the
diminution of the quantity of saltpetre and sulphur, or, in other
words, to the increase of the quantity of powder; and that the fourth
change must contain but a small quantity of each, whilst the sixth or
last change contains none, except that which is in the composition
of the powder. The effect, therefore, must be proportionate; for, it
must be apparent, that this diminution of nitre and sulphur, and the
increase of powder, must render each charge more explosive, or, in
other words, the combustion more instantaneous, and that this effect
characterizes each of the changes in succession, is a result which
necessarily follows.

The instructions given by Morel for employing these changes, in
the charging of cases, are thus: We take the above composition for
the third case of the sun. The first case is of common fire; the
second of silver rain; the third of two charges of common fire, and
afterwards a charge of No. 1, the second two charges of No. 2, the
third three charges of No. 3, the fourth four charges of No. 4, the
fifth four charges of No. 5, and two charges of No. 6. The fourth
case is composed of brilliant fire; the fifth the same as the third,
and the sixth of large or grand jessamine.

We may merely remark, that the sun must be supported very firmly, and
that it ceases to revolve at the fourth, fifth, and sixth numbers.

_Sec. IV. Of Fixed Suns._

Fixed suns are so called, because they remain stationary, and exhibit
the appearance of a sun with innumerable rays. A fixed sun is formed
by putting eight or more strips of board across each other, so that
each arm may proceed from a common centre, in which a sun is painted
on silk. To the extremities of these arms are attached, to each one
in succession, a case of brilliant fire, which, by means of bodies
fixed in the usual manner, go off together. The two arms below,
forming right angles with each other, are longer than the rest; so is
also the upper and vertical arm. This, however, depends upon fancy.
The cases are tied to these arms; and, after the leaders are fixed
from the mouth of one case to that of the other, they terminate
at the bottom and hang below the vertical arm. Fire is first
communicated to the hanging match.

Fixed suns are usually employed as a decoration for other works. They
are sometimes sixty feet in diameter, and variously decorated. They
are commonly, however, ten feet. The fire extends a considerable
distance, sometimes, it is said, to the distance of thirty feet; but
this must depend on the size of the cases.

_Sec. V. Of Fixed Suns with Transparent Faces._

Fixed suns may be made with transparent faces in the following
manner: Two rows of cases must be fixed in radii from the face of
the sun, the sun being in the centre; and these cases, being placed
alternately one above the other, and preserving the same distance
all round, present what is called a double glory, and make the rays
strong and full. The frame or sun-wheel is made thus: Have a circular
flat nave, made very strong, 12 inches in diameter, and fix six
strong flat spokes, proceeding from the circle that contains the
sun's face to the extremity of the wheel, and also two other hoops,
placed between it and the sun. To these, and the external wheel, the
cases are tied. When the cases are tied on, leaders are attached from
the upper to the under cases. The front of these spokes supports a
circular fell, five feet in diameter. Within this is another fell,
smaller in diameter by the length of one of the sun cases; and within
this also is a third fell, whose diameter must be less than the
second by the length of one case and one third. The fells are divided
into as many equal parts as we employ cases, which may be from
twenty-four to forty-four. At each division, fix a flat iron staple.
These staples must be made to fix the cases and hold them fast on the
wheel. The staples must be so placed, that one row of cases may lie
in the middle of the intervals of the other. There is a spindle in
the centre of the block of the sun, to which a small hexagonal wheel
is put. The cases of this wheel must be filled with the same charge
as the cases of the sun. Two cases must burn at a time, and begin
with them on the fells. The pipes of communication are to be carried
from one to the other, and from one side of the sun to the wheel in
the middle, and from thence to the other side of the sun. They will
hold the wheel steady, when the sun is fixing up.

A sun thus made is called a brilliant sun, as there appears nothing
but sparks of brilliant fire, the wood-work being covered with fire
from the wheel in the middle. A transparent face is usually made with
pasteboard, by cutting out the eyes, nose, and mouth, for the sparks
of the wheel to appear through. A face may be painted on oiled paper,
or Persian silk, put over a hoop, and supported by three or four
pieces of wire at six inches distance from the wheel in the centre.
The silk may be painted according to fancy.

As to the size of cases for a sun of five feet in diameter,
half-pound cases, filled ten inches with composition, is considered a
good proportion.

_Sec. VI. Of the Rose-Piece and Sun._

This exhibition may be made in such a manner as to produce a pleasing
effect. A rose-piece may be used for a mutation, or change of a
regulated piece, or fixed by itself. It makes the best appearance,
when made large. If its exterior diameter be six feet, it will be a
good size. Let the exterior fell be made of wood, and supported by
four wooden spokes. All the other parts, on which the illuminations
are fixed, must be made of strong iron-wire. On the exterior fell,
place as many half pound cases of brilliant charge, as will be
sufficient; but the more, the greater will be the effect, for the
nearer the cases are placed, the stronger will be the rays of the
sun. The illuminations should be placed within three inches of each
other. They must all be fired together, and burn some time before
the sun is lighted, which may be done by carrying a leader from the
middle of one of the illuminations to the mouth of one of the sun
cases.

_Sec. VII. Of the Manner of changing a Horizontal to a Vertical
Wheel, and representing a Sun in front._

In order to produce this change, the wheel for this purpose should
be about three feet in diameter, and its fell circular, on which tie
sixteen half-pound cases, filled with brilliant charge. Two of these
cases must burn at a time. On each end of the nave is to be a tin
barrel of the same construction as those on the regulated piece.
We must then have a stand, made of any height, about three or four
inches square, and saw off from the top a piece two feet long. This
piece is then to be joined again, at the place where it was cut, with
a hinge on one side, so that it may lift up and down in the front of
the stand. Then fix on the top of the bottom part of the stand, on
each side, a bracket, which must project, at right angles with the
stand, one foot from the front, for the short piece to rest on. These
brackets are to be placed a little above the joint of the post, so
that, when the upper stand falls, it may lie between them at right
angles with the bottom stand; which may be done by fixing a piece of
wood one foot long between the brackets, and even with the top of
the bottom stand. Then, as the brackets rise above the bottom stand,
they will form a channel for the short post to lie in, and keep it
steady without straining the hinge. On the side of the short post,
opposite the hinge, nail a piece of wood of such a length, that, when
the post is perpendicular, it may reach about one and a half feet
down the long post; to which, being tied, it will hold the short
stand upright. The stand being thus prepared, in the top of it, fix a
spindle ten inches long. On this spindle put the wheel; then fix on a
brilliant sun, with a _single glory_. The diameter of this sun must
be six inches less than that of the wheel. When we fire this piece,
attention must be paid to light the wheel first, and let it run
horizontally till four cases are consumed. Then, from the end of the
fourth case, carry a leader into the tin barrel that turns over the
end of the stand. This leader must be met by another, brought through
the top of the post, from a case filled with a strong port-fire
charge, and tied to the bottom post, with its mouth facing the pack
thread, which holds up the stand; so that, when this case is lighted
it will burn the pack thread and let the wheel fall forward, by which
means it will become vertical. Then from the last case of the wheel,
carry a leader into the barrel, next the sun, which will begin as
soon as the wheel is burnt out.

_Sec. VIII. Of Caprices and Fire-Wands._

Caprices are so called from the particular motion they assume, and
are regulated according to the order and manner of their firing.

A perpendicular shaft, or post, is first provided, in which are
placed two sets of spokes at some distance from each other. At the
extremities of these spokes, joints are made, on which the cases
are fixed. These cases communicate with each other by leaders. The
first which takes fire, discharges upwards; the second, vertically;
the third, horizontally; and the fourth, fifth, sixth, and seventh,
go off at the same time; _viz._ the fourth, upwards; the fifth,
vertically, a little inclined; the sixth, horizontally; and the
seventh, vertically. The match of communication is fixed by a
port-fire.

The arrangement of this piece, to produce the effect, depends on the
construction of the wood work.

The great falling caprice differs from the foregoing in the following
particular, that it separates itself in the midst of its fire into
three parts. It is formed of three wheels, which appear as one; but
at a certain time after the fire is communicated, they separate and
occupy certain positions.

Mercury's Wand, as it is called, is formed by placing, across
each other, two pieces of wood, and at the extremity of each four
lances parallel to each other, and one obliquely. These lances
of illumination must be connected by leaders. Circular bands are
attached to the extremity of each leg, which terminates in the
centre, and the wings or legs move in opposite directions. The double
crescents, thus formed, produce, in turning, a variety of figures.

_Sec. IX. Of Palm and other Trees._

The representation of trees is considered an elegant fire-work. Palm
trees are shown by fixing an upright piece, which serves as a trunk,
and attaching to it a number of pieces, resembling in effect the
branches of a tree. The extremities or branches are decorated with
gerbes, and sometimes with marrons, arranged in such a manner that
they may go off together.

For Yew trees, cases of brilliant fire, jessamine, or Chinese are
used. In making this representation, the upright piece is usually
four feet in length, two inches in breadth, and one inch thick. At
the top we fix, on the flat side, a hoop fourteen inches in diameter,
and round its edge and front, place illuminations, and in its centre
a five-pointed star. At a foot and a half from the edge of the hoop,
two cases of brilliant fire are usually placed, one on each side.
These cases should be one foot long each. Below these are usually
fixed two more cases, at such a distance that their mouths may almost
meet those at top. Two other cases are sometimes added, which
ought to be parallel with the last. The cases are then clothed with
leaders, so that they, with the illuminations and stars at top, may
all take fire together.

Fire trees may be formed by placing cases at an angle of 45 degrees,
inclining upwards from the trunk, and at certain distances from each
other. The two last cases may incline downwards. Cases may also be
placed on the trunk itself, so that the whole will resemble a body
of fire. Fire trees are commonly made about six feet long and three
inches in diameter. The cases are generally fixed to pegs. At the
top of the tree, a four-inch mortar is fixed, which is loaded with
stars, rains, or crackers. In the middle of this mortar, we may place
a case filled with any sort of charge, which must be fired with
the other cases. Brilliant fire is generally employed. The fire is
communicated, as in other works, by means of leaders, which are fired
at the bottom.

There is also another exhibition often made with the so called
_illuminated yew-tree_. The middle piece or stem on which the
branches are placed, is generally eight feet six inches high.
The branches all incline downward, and shorten as they go up.
The number of branches on each side is six, and their length is
determined according to judgment. When the branches are fixed, place
illuminating port-fires on the top of each, as many as are required.
Behind the top of the stem, fasten a gerbe or fountain of Chinese
fire, which must be fired at the beginning of the illuminations on
the tree.

Fires are often made to intersect each other, which has a good
effect. For this purpose a perpendicular post is provided, of any
thickness, so that it is sufficiently strong to hold the cases.
There are two pieces of wood which go across the post, two feet six
inches apart and two feet in length. On the end of each of these
pieces there is usually a five-pointed star. Six stars are mostly
employed. Pegs are fixed to the post in such a way that two of them
incline upwards and two downwards, both forming an angle of ninety
degrees, or forty-five degrees with the post. To these pegs are fixed
half pound cases of brilliant fire. All the cases and stars must be
fired at once. It is obvious that by this arrangement of the cases,
the fires must cross, and thus by intersecting each other afford a
greater variety.

_Sec. X. Of the Pyramid of Flower Pots._

This piece is formed by attaching to a post, ten or twelve feet high,
and placed perpendicularly in the ground, four rails or pieces,
two feet apart, which must diminish in length, so as to represent a
pyramid. The bottom rail must be six feet long. On the bottom rail
fix five paper mortars, each three and a half inches in diameter. Let
one be opposite the post, and the other four equally distant on each
side. Load these mortars with serpents, crackers, stars, &c. In the
centre of each mortar fix a case of spur-fire. On the second rail fix
four mortars so as to stand exactly in the middle of the intervals
of those on the bottom rail. On the third rail, place three mortars,
on the fourth, two; and on the top of the post, one. All the mortars
must incline a little forwards, that they may easily discharge; and
the spur-fire rammed exactly alike, that the mortars may all be fired
at the same time. The pipes of communication being prepared, carry
them from one spur-fire to the other.

_Sec. XI. Of the Dodecaedron._

The piece, required in forming a twelve sided figure, is prepared
in the following manner: A ball must be turned out of solid wood,
fourteen inches in diameter, and its surface is to be divided into
fourteen equal parts. In each division bore holes of a half inch in
diameter, perpendicular to the centre, so that they may all meet in
the middle. In the inside of each hole, let there be turned a female
screw. To all the holes but one must be made a round spoke, five feet
long, with four inches of the screw at one end to fit the holes. In
the screw end of all the spokes, bore a hole five inches up, which
must be bored slanting so as to come out at one side a little above
the screw. From these holes cut a small groove along the spoke,
within six inches of the other end, where another hole through to the
other side of the spoke is made. To this end fix a spindle, on which
put a small wheel of three or four sides, each side six or seven
inches long; these sides must have grooves cut in them, large enough
to receive a two or four-ounce case. When these wheels are clothed
put them on the spindles, and at the end of each spindle attach a nut
to keep the wheel from falling off.

The wheels being thus fixed, carry a pipe from the mouth of the
first case on each wheel through the hole in the side of the spoke,
and from thence along the groove and through the other hole, so as
to hang out at the screw end about an inch. The spokes being all
prepared in this manner, a post must be provided on which the piece
is to be fired, having an iron screw in the top of it to fit one
of the holes in the ball. On the screw attach the ball and then in
the top hole of the ball put a little meal-powder, and some loose
quick-match. After this, screw in all the spokes, and in one side
of the ball bore a hole, in which put a leader and secure it at the
end. By this leader the powder and match in the centre are fired,
which will light the match at the end of the spokes all at once, and
by which all the wheels will be lighted at the same time. There may
be an addition to this piece by fixing a small globe on each wheel,
or one on the top wheel only. Gray charge may be used for the wheel
cases.

_Sec. XII. Of Cascades of Fire._

Cascades of fire may be made of any size, and with cases from a half
pound to a pound, or more. Half pound cases are usually the size
employed. Cascades may be made either fixed, or turning. The former
are an assemblage of pieces of wood, furnished with cases charged
with Chinese fire, and placed one above the other. The distance may
be more or less; sometimes from eight to fifteen feet. The latter,
or turning cascades, are constructed about four feet in diameter.
The wheel is made to turn on a pivot, and is put in motion by
attaching to it, in the usual manner, cases of white fire. These
play horizontally. The cases of Chinese fire, which play downwards,
are fixed to the wheel, or to another wheel below this, or above
it, according to fancy, and are placed with their mouths downwards.
Sometimes in fact they play upwards, and for that purpose are made to
incline outwards. In the centre, there is a case or two of brilliant
fire.

It is obvious, that this arrangement not only gives a motion to the
wheel, and to the cases of Chinese fire, but produces in effect a
circular sheet, which falls like a cascade.

By having an upright piece, stuck in the ground, on which are fixed
three or more horizontal wheels, or segments of a circle, made
permanent, and at about three feet from each other, diminishing,
however, as they go up, and also in their diameter, a frame will be
formed capable of holding a great number of cases. The first segment
may be four feet in diameter. The top pieces may be of any length,
so as to hold the cases at a little distance from each other. All
the cross pieces are to be fixed horizontally, and supported by
brackets. The bottom cross piece, or segment, should be about one
foot six inches broad in the middle; the second, one foot; the third,
nine inches; and the top piece, four inches. The cases may be made
of any length, but must be filled with a brilliant charge. Bits of
wood ought to be nailed on the edges of the cross pieces, having a
groove cut in each piece, and sufficiently large for a case to lie
in. These bits of wood are fixed, so as to incline downwards, and
that the fire from one tier of cases may play over the other. Leaders
are carried from one to the other, as before mentioned. Let there be
a pipe, hung from the mouth of one of these cases, covered at the
end with a single paper, which is burnt to fire the cascade. Nine
cases generally form the first tier; seven, the second, four, the
third; and three, the last. These cases play downwards, except the
three at top, one of which is vertical and the other two inclining at
an angle of about forty-five degrees. The arrangement may be varied
at pleasure. The only thing to be attended to is, to fix the cases
in such a way, that the fire which proceeds from them may pass over
the tier immediately underneath, that the effect may be general and
uniform. Chinese fire may be used, as in the former instance.

_Sec. XIII. Of Chinese Fountains, and Parasols._

The manner of constructing the wood work of a Chinese fountain is as
follows: Procure a perpendicular piece of wood, seven feet long, and
two and a half inches square. At sixteen inches from the top, fix on
the front a cross piece, one inch thick, and two and a half inches
broad; with the broad side up. Below this, fix three more pieces of
the same width and thickness, at sixteen inches from each other. Let
the bottom rail be five feet long, and the others of such a length as
to allow the fire-pumps to stand in the middle of the intervals of
each other. The pyramid being thus made, fix in the holes, made in
the bottom rail, five fire-pumps, at equal distances: on the second
rail, place four pumps; on the third, three; on the fourth, two; and
on the top of the post, one. Place them all, however, to incline a
little forward, so that when they throw out the stars, they may not
strike against the cross rails. The fire-pumps are to be clothed with
leaders, in order that they may all be fired together.

Cases for _Fire-pumps_ are made in the same manner as those for
tourbillons. See _Fire-pump_, and also _Fire-pots_ of various kinds.

The effect of these cases depends entirely on the star-composition.
Stars, previously moulded, are introduced into them along with
meal-powder.

Parasols are also formed with Chinese fire. A horizontal wheel is
provided, and its circumference is clothed with eight or ten cases
of that fire. These cases may be five-sixths of an inch in diameter,
and, when inflamed, should throw their fire horizontally. The fire,
in this instance, is made to resemble a _sheaf_; but the ordinary
composition is generally used. The cases, however, should play
horizontally. To make the wheel turn on its pivot, two cases of white
fire are attached to it. The parasol, produced by the fire, is from
twenty-five to thirty feet in diameter. It is formed in consequence
of the fire coming in contact, and producing a concave sheet in its
fall, resembling a parasol when extended.

_Sec. XIV. Of Wings or Cross Fire._

Nearly similar to one of the pieces described, that of the
representation of a tree, is the cross-fire, or _wings_, a name given
to it, because it resembles the sails, or wings of a windmill.

In forming this piece, two sticks, eight feet in length, are
provided, and through the centre of each, a square hole is made, to
receive a piece of iron of the same size, through which is a hole to
admit a pivot.

When these sticks are put together, there must be a sufficient
distance between them to prevent their rubbing each other. Five
cases, charged with the composition of brilliant fire, are fixed to
each extremity, proceeding towards the centre, at a short distance
apart, and making in all twenty cases. Four of these cases are
placed at each end, nearly horizontally, resembling the rounds of a
ladder, the sticks being nearly vertical; and the one nearest the
centre is placed almost vertically, or rather obliquely. The cases,
being connected with leaders, when fired, turn with the sticks in an
_opposite_ direction to each other.

When three wheels are each furnished with two rounds of white and
coloured fire, and are so arranged, that the periphery of each should
pass over in succession at the distance of ninety degrees of the
perimeter, this piece is then called by the whimsical name of the
_love-knot_.

_Sec. XV. Of Galleries of Fire, and Batteries of Roman and Mosaic
Candles._

Galleries of fire are formed by attaching, to long strips of wood,
at convenient distances from each other, cases of Chinese fire, which
go off together. At the end of each case, is put a marron, which,
when the case is burnt, ends with an explosion.

To form batteries with marrons, in connection with Roman candles,
they are tied at two feet distance from each other, on long sticks,
leaders being attached. These batteries, like the fire gallery,
usually accompany other fire-works.

We may here remark, that _thunder_ is imitated by marrons, which are
fixed in the same way two feet apart. To produce the effect, and
increase the report, it is necessary to use them of different sizes,
from a quarter of an inch to three inches caliber. They should be
preceded by flashes of _lightning_, which is imitated either with
powdered rosin, or lycopodium, in the manner described in our chapter
on _Theatrical Fire-Works_.

_Sec. XVI. Of Girandoles, and their Modifications._

Girandoles, for the purpose here noticed, are nothing more than
wheels which turn on a pivot. They are made of light wood, with a rim
similar to that of a sieve, and are clothed with cases. Two cases are
fired at a time, which burn in an opposite direction.

Girandoles may be made to imitate a parasol, by placing,
horizontally, cases charged with the blue-fire composition, or with
that of the Chinese fire. Cascades may be formed, by arranging them
vertically, horizontally, and some at an angle of ten or fifteen
degrees from the horizon. The _bunch of flowers_ is represented
by using, at the same time, cases of 10/12ths, 11/12ths, and one
inch, charged with Chinese composition, as given in the table for
calibers of that diameter. See _Chinese Fire_. Crackers are formed by
attaching Roman candles and Mosaic simples, and the sheaf is shown
by fixing in the centre some empty cases, on which are strung small
rockets, which are fired by the last case.

There are different modes of varying the effect of the girandole.
They may imitate the fire-rain, by employing cases charged with that
composition, which is given in the chapter on _Theatrical Fire-Works_.

_Sec. XVII. Of Cracking Caprices._

For this piece, a circular table is formed about twenty inches in
diameter, and one inch and a quarter thick. There is a hole made in
the centre, which is furnished with a pivot.

Twelve inches from the circumference, and at equal distances, eight
holes are to be bored, to receive the same number of pots, of two
inches caliber; and, in the immediate vicinity of the centre hole,
which receives the pivot, four more are made, for four other pots.

Eight arms, three inches long, project from the table at equal
distances, on which is fastened a hoop one inch in width. The
fire-pots are now put in the different apertures, which are made
sometimes to screw in; and the frame, of which we have spoken, is
furnished with cases of brilliant fire.

It is necessary that this piece should go off at three fires; but the
order of firing may be varied according to circumstances.

_Sec. XVIII. Of the Projected Regulated Piece of Nine Mutations._

A regulated piece, if well executed, is considered as curious in its
effect as any other in pyrotechny. It consists of fixed and moveable
pieces on one spindle, representing various figures, which take fire
successively one upon another, without any assistance after lighting
the first mutation.

I. Names of the mutations, with the colour of fire, and size of the
case, belonging to each.

_First Mutation._--This is a hexagon vertical wheel, illuminated in
front with small port-fires, tied on the spokes. This wheel must be
clothed with two-ounce cases, filled with black charge. The length
of these cases is determined by the size of the wheel, but each must
burn singly.

_Second Mutation._--This is a fixed piece, called a golden glory,
by reason of the cases being filled with spur fire. The cases must
stand perpendicular to the block, on which they are fixed, so that,
when burning, they may represent a _glory_ of fire. This mutation is
generally composed of five, or seven two-ounce cases.

_Third Mutation._--This is moveable, and is only an octagon vertical
wheel, clothed with four-ounce cases, filled with brilliant charge.
Two of these cases must burn at a time. In this wheel, we may make
changes of fire.

_Fourth Mutation._--This is a fixed sun of brilliant fire, consisting
of twelve four-ounce cases. The necks of these cases must be a little
larger than those of four-ounce wheel cases. In this mutation, may
be made a change of fire, by filling the cases half with brilliant
charge, and half with gray.

_Fifth Mutation._--This is a fixed piece called the _porcupine
quills_. This piece consists of twelve spokes, standing perpendicular
to the block in which they are fixed. On each of these spokes, near
the end, must be placed a four-ounce case of brilliant fire. All
these cases must incline either to the right or left, so that they
may all play one way.

_Sixth Mutation._--This is a standing piece called the cross fire.
This mutation consists of eight spokes fixed in a block. Near the end
of each of the spokes, must be tied two four-ounce cases of white
charge, one across the other; so that the fires from the cases on one
spoke may intersect the fire from the cases on the other.

_Seventh Mutation._--This is a fixed wheel with two circular fells,
on which are placed sixteen eight-ounce cases of brilliant fire, in
the form of a star. This piece is called a fixed star of _wild fire_.

_Eighth Mutation._--This is a beautiful piece, called a brilliant
star piece. It consists of six spokes, which are strengthened by two
fells of a hexagon form, at some distance from each other. At the
end of each spoke, in the front, is fixed a brilliant star of five
points; and on each side of every star is placed a four-ounce case of
black or gray charge. These cases must be placed with their mouths
sidewise, so that their fires may cross each other.

_Ninth Mutation._--This is a wheel piece. It is composed of six
long spokes, with a hexagon vertical wheel at the end of each.
These wheels run on spindles in front of the spokes. All the wheels
are lighted together. Two-ounce cases will be sufficient for these
wheels, and may be filled with any coloured charge.

II. With respect to the proportion of these mutations, with the
method of conveying the fire from one to the other, and the distance
they stand from each other on the spindle, the following general
remarks will be sufficient.

The _first mutation_ must be a hexagon vertical wheel fourteen
inches in diameter. On one side of the block, whose diameter is two
and one-fourth inches, is fixed a tin barrel. This barrel must be a
little less in diameter than the nave. Let the length of the barrel,
and block be six inches. Having fixed the cases on the wheel, carry a
leader, from the tail of the last case, into the tin barrel, through
a hole, made on purpose, two inches from the block. At the end of
this leader, let there be about one inch, or two, of loose match; but
be careful to secure the hole, in which the pipe is put, to prevent
any sparks falling in, which would light the second mutation before
its time, and confuse the whole.

The _second mutation_ is thus made. Have a nave, turned two and a
half inches in diameter, and three long; then let half an inch of
that end, which faces the first wheel, be turned, so as to fit easy
into the tin barrel of the first mutation, which must turn round it
without touching. On the other end of the block, fix a tin barrel
No. 2. This barrel must be six inches long, and only half an inch of
it to fit on the block. Round the nave, fix five spokes, one inch
and a half long each. The diameter of the spokes must be equal to
a two-ounce former. On these spokes, put five seven-inch two-ounce
cases of spur-fire, and carry leaders from the mouth of one to the
other, that they may all light together. Then, from the mouth of one
of these cases, carry a leader through a hole bored slantwise in the
nave, from between the spokes to the front of the block, near the
spindle hole. The end of this leader must project out of the hole
into the barrel of the first mutation; so that, when the pipe, which
comes from the end of the last case on the first wheel, flashes, it
may take fire and light the second mutation. To communicate the fire
to the third mutation, bore a hole near the bottom of one of the five
cases to the composition; and from thence carry a leader into a hole,
made in the middle of the barrel. This hole must be covered with
pasted paper.

The _third mutation_ may be either an octagon or hexagon wheel,
twenty inches in diameter. Let the nave be three and a quarter inches
in diameter, and three and a half in length. One and a half inches of
the front of the nave must be made to fit in the barrel No. 2. On the
other end of the block, fix a tin barrel No. 3. This barrel must be
six and a half inches in length, one inch of which must fit over the
block. The cases of this wheel must burn two at a time, and, from the
mouths of the two first cases, carry a leader through holes in the
nave, into the barrel of the second mutation, after the usual manner.
But besides these leaders, let a pipe go across the wheel from one of
the first cases to the other. Then, from the tail of one of the last
cases, carry a pipe into a hole in the middle of the barrel No. 3: at
the end of this pipe, let there be some loose quick match.

_Fourth and Fifth Mutations._--Their naves are made of one piece,
which, from the barrel of the fourth, to the commencement of the
sixth, is fourteen inches. The block of the fourth is four inches
in diameter, having ten or twelve short spokes, on which are fixed
eleven inch eight-ounce cases. The front of this block must fit easy
in the barrel of the third wheel. Clothe the cases, so that they
may all light together; and let a pipe be carried through a hole in
the block into the barrel No. 3, in order to receive the fire from
the leader, brought from the last case on the wheel. The nave of
the fifth mutation must be four and a half inches in diameter, and
furnished with ten or twelve spokes, eighteen inches in length each.
These spokes must stand seven inches distant from the spokes of the
fourth mutation, and, at the end of each spoke, tie a four-ounce case
as No. 5. All these cases are to be lighted together, by a leader
brought from the end of one of the cases on No. 4.

_Sixth and Seventh Mutations._--The blocks of these two mutations are
turned out of one piece of wood, whose length from the barrel of the
fifth wheel, to the block of the eighth wheel, is fifteen inches.
The block of the sixth wheel is five inches in diameter, having
eight spokes, each two feet four inches long. At the end of each
spoke, tie two four-ounce cases, as in No. 6. All these cases must
be fired at the same time, by a pipe brought from the end of one of
the cases on the fifth mutation. Let the distance between the spokes
of the sixth, and those in the fifth mutation, be seven inches.
The nave of the seventh mutation must be five and a half inches in
diameter, and furnished with eight spokes. On the front of them, two
circular fells, one of four feet eight inches in diameter, and the
other, three feet eleven inches, are to be fixed. On these fells, tie
sixteen eight-ounce cases, or pound cases, as in No. 7, and carry
leaders from one to the other, so that they may be fired at the same
time. This mutation must be fired by a leader, brought from the tail
of one of the cases on the sixth mutation.

_Eighth and Ninth Mutations._--The blocks of these may be turned out
of one piece, whose length from the barrel of the seventh mutation
to the block of the ninth, must be twelve inches. The block of the
eighth, six inches in diameter, must contain six spokes, each three
feet in length, and strengthened by an hexagon fell, within three
or four inches of the ends of the spokes. Close to the end of each
spoke, in the front, fix a five-pointed brilliant star, and seven
inches below each star, attach two ten-inch eight-ounce cases, so
that the upper ends of the cases may rest on the fells, and their
ends on the spokes. Each of these cases must be placed parallel to
the opposite fell.

_Ninth Mutation._--The block of the ninth mutation is seven inches
in diameter, and holds six spokes, six feet long each, with holes
and grooves for leaders, as those in the dodecaedron. At the end of
each spoke in the front, fix a spindle for a hexagon vertical wheel,
ten inches in diameter, as in No. 9. When these wheels are on, carry
a leader from each into the block, so that they may all meet. Then
lead a pipe from the end of one of the cases of the eighth mutation,
through a hole bored in the block of the ninth, to meet the leaders
from the vertical wheels, in order that they may be fired together.

Having thus given a brief description of this complicated work, the
performance of which depends so much on the accuracy of its parts, we
will now add a few remarks respecting the formation of spindles.

For the larger pieces, the spindles should be made very strong
and exact. The instructions on this head are, that for a piece of
nine mutations, let the spindle be, at the large end, one inch in
diameter, and continue that thickness as far as the seventh mutation,
and from thence to the fifth, let its diameter be three-quarters of
an inch. The other proportions, then, are, from the fourth to the
second, half an inch; and from the second to the end, three-eighths
of an inch. At the small end must be a nut, to keep on the first
wheel, and at the thick end, a large nut; so that the screw part of
the spindle being put through a post, and a nut screwed on tight, the
spindle will be held fast and steady. The wheels, however, ought to
run easy and without sticking. The fixed pieces are made on different
blocks, and the leaders must be joined, after they are fixed on the
spindle. The best method of preventing the fixed mutations from
moving on the spindle, is to bore a hole a little larger than the
diameter of the spindle; and, at each end of the block, over the
hole, fasten a piece of brass, with a square hole in it to fit the
spindle.

Similar to this piece of nine mutations is the _Pièce Pyrique_ of the
French, which consists of a great variety of fixed and moving pieces,
that are fired alternately, but in regular succession. This piece we
purpose to describe in the following section.

_Sec. XIX. Of the Pyric or Fire-Piece._

This, we have remarked, is a combination of pieces, calculated, like
the one we have described, to produce a variety of fires, variously
arranged and distributed.

The pyric piece commonly commences with a turning sun. This sun
consists of three cases, fixed to three arms proceeding from the
centre. They are attached by means of a string, and have leaders
which go from one to the other of the cases. See _Sun_. This sun
communicates its fire to a fixed sun, formed of eight or nine strips
of board, crossing each other, or as many spokes from a hub, to which
are attached, lengthwise, as many cases, whose mouths are made to
communicate fire by means of leaders; so that each case presents the
appearance we have before described. Then follows a wheel consisting
of two or more concentric circles, and round which are placed eight
cases, with their mouths inclining a little upwards. These cases are
generally charged with brilliant fire. They communicate with each
other in the usual manner, and afterwards with a fixed star, placed
on a stick, proceeding from the horizontal axis. This star is made
of two cases, charged with Chinese fire, with their mouths upwards,
and forming, with each other, an angle of forty-five degrees. This
fire is then communicated to another wheel, and from that to one, on
which, at certain distances, are fixed six smaller wheels, furnished
with six cases each; so that the whole are put in motion at one time,
the fire being communicated at the same period. The appearance of
these smaller wheels, as the cases may be charged with the coloured
fire-composition, is such as to exhibit the motion of a screw; which,
however, depends on the structure of the wheel. The fire from this
may then communicate to other wheels of the same kind, to cases
of brilliant fire, to marrons and the like, differently arranged
according to fancy. Cylinders of copper or tin, called _barrels_ by
some, are used in the arrangement, in the manner already described.
In fact, the remarks we have before made on the regulated piece of
nine mutations, the manner of forming as well as of executing it,
will apply to the Pyric-piece.

_Sec. XX. Of Sundry Illuminated Figures._

There are various illuminated pieces, some of which we purpose to
notice in this section.

The illuminated pyramid, with Archimedean screws, a globe, and
vertical sun, may be exhibited in the following manner: Let a pyramid
be made twenty-one feet in height, and the height of the pedestal
six feet, and breadth nine feet, having a space between the rails of
six inches. They must be made as thin as possible, and in all put
port-fires at intervals of four inches. The Archimedean screws are
placed on the pedestal. They are nothing more than double spiral
wheels, on which the cases are placed, but horizontally instead of
obliquely. The vertical sun, placed four feet below the top of the
pyramid, may consist of twelve rays. The globe on the top may be
made in proportion to the pyramid. The leaders must be prepared and
arranged in such a manner, that all the illuminating port-fires, or
lances, screws, globe, and sun may take fire together.

Transparent stars with illuminated rays are formed, by making a
strong circular block or body for the star, two feet in diameter,
and attaching to it illuminated rays. In the centre of the front of
the body, fix a spindle, on which put a double triangular wheel, six
inches in diameter, clothed with two-ounce cases of brilliant charge.
The cases on this wheel must burn only one at a time.

Round the edge of the body, nail a hoop made of thin wood or tin,
which must project in front six or seven inches. In this hoop, cut
three or four holes to let out the smoke from the wheel. The star may
be cut out of strong pasteboard or tin in the following manner: Cut
a round piece of pasteboard, two feet in diameter, on which draw a
star, and cut it out. Over the vacancy, paste Persian silk, and paint
the letters yellow; and also four of the rays yellow, and four red.
This transparent star is to be fixed to the wooden hoop by a screw,
to take off and on. The illuminated rays are made of thin wood,
with tin sockets, fixed on their sides, within four inches of each
other. In these rockets, put the illuminating port-fires, or lances;
and behind the point of each ray, attach a half pound case of gray,
black, or Chinese fire. The illuminated rays are to be lighted at the
same time as the triangular wheel, or after it is burnt out. This may
be done by a tin barrel, in the manner described in the regulated
piece. Into this barrel, carry a leader from the illuminated rays,
through the back of the star, which must be met by another leader,
brought from the tail of the last case on the wheel.

The regulated illuminated spiral piece, with a projected star wheel,
also illuminated, is made by procuring a block, eight inches in
diameter, and putting in six iron spokes, which serve for spindles
for the spiral wheels. These wheels are made one and a half feet
in diameter, and three feet in height. The spindles must be of
sufficient length to keep the wheels four or five inches from one
another. At the end of each spindle, put a screw nut. On these
spindles, the wheels, that hang downwards, are to run. On the
spindles, which stand upwards, must be a shoulder, for the blocks
of the wheels to run on. The projected star wheel turns on the same
spindle on which the large block is fixed. This spindle must be long
enough to admit the star-wheel to project a little before the spiral
wheels. The exterior diameter of the star wheel is five feet five
inches. On this wheel, three circles of iron wire are to be fixed, to
which attach either port, or other illuminating fires. On the block,
place a transparent star, or a large five-pointed brilliant star. The
cases on this wheel may burn four at once. The cases on the spiral
wheels must be placed parallel to their fells and burn two at a time.

In order to make a figure-piece, with five-pointed stars,
illuminated, all that is necessary is to have a vertical wheel about
one foot in diameter, and furnished with six four-ounce cases of
different coloured charge, which must burn double. On the frame of
the figure piece, fix five-pointed brilliant or blue stars, rammed
four inches with composition. Let the space between each star be
eight inches, and, at each point, fix a gerbe or case of Chinese
fire. The gerbe, stars, and wheel are to be lighted at the same time.

The illuminated star wheel may be formed by procuring a fell about
four feet in diameter, and placing, within this fell, three circles
of iron wire, one smaller than the other, so that the diameter of
the least may be about ten inches. Place the port, or other fires on
these fells, with their mouths inclining outwards, and the port-fires
on the points of the star, with their mouths projecting in front. The
exterior fell must be clothed with four-ounce cases of gray charge.
They must burn four at a time and be lighted at the same time with
the illuminations.

The illuminated regulating piece as it is called, consists of flat
wooden spokes, each five feet long, and at the end of each, a
vertical wheel, ten inches diameter, and clothed with six four-ounce
cases of brilliant fire. These cases burn one at a time. On two of
the spokes of each wheel, two port-fires are attached, which must be
lighted with the first case of the wheel. On each spoke, behind the
wheels, place six cases of the same size with those on the wheels.
These cases must be tied across the spokes with their mouths in one
direction, and be made to take fire in succession.

The diameter of the large wheel must be two and a half feet, and
its fell made of wood, which is to be fixed to the large spokes.
Twenty-four cases of the same kind are fixed on this wheel, and burn
four at a time. On the circles of iron-wire, already mentioned,
illuminating port-fires are attached. The star-points on the large
spokes may be made of thin ash-hoops. The diameter of these points,
close to the centre wheel, is usually eleven inches. On these,
port-fires are placed, three and a half inches distant from each
other.

The illuminated double cone-wheel is nothing more than a double cone,
formed of a number of hoops, and supported by three or four pieces
of wood, in the manner of the spiral wheels. The wheel to which the
cones are attached, base to base, is two feet six inches in diameter,
and the height of each cone is three feet six inches. Port-fires, or
lances, are tied to each of the hoops, in a horizontal direction,
with their mouths outwards. The cases are eight-ounce, and play
horizontally, two at a time. The spindle for this piece must rise
three feet above the point of the cone at top; so that its length
will be ten feet four inches from the top of the post, in which it
is fixed, allowing four inches for the thickness of the block of the
wheel. The whole weight of the wheel and cones must be made to bear
on a shoulder in the spindle, on which the block of the wheel is
to turn. On the top of the spindle, fix a sun, composed of sixteen
four-ounce cases of brilliant fire. These cases must be stuck into
a block, six inches in diameter. In the front of this sun, put a
circular vertical wheel, sixteen inches in diameter. On the front of
this wheel, form a spiral with wire, to which attach illuminations
in the usual manner. This wheel is to be fired, when the cones are
burnt out, which may be done as before described. The sun must not be
fired, until the vertical wheel is burnt out. Three vertical wheels
illuminated, which turn on their own naves upon a horizontal table,
is a piece readily formed. It consists in having a table, three feet
in diameter fixed horizontally on the top of a post, with three
wheels that turn round on it. There are three spokes, joined to a
triangular flat piece of wood, in the middle of which, a hole is made
to fit easily over a spindle placed in the centre of the table. There
are three pieces of wood four or five inches long, and two inches
square, fixed on the under sides of the spokes. In these pieces,
holes are made lengthwise, to receive the thin parts of the blocks
of the wheels, which, when in, are prevented from coming out by a
small iron pin that runs through the end of each. The three vertical
octagon wheels, each eighteen inches in diameter, have blocks
sufficiently long, for three or four inches to rest on the table.
Round these a number of sharp points of wire are driven, (which must
not project out of the blocks more than 1/16th of an inch), and the
clothing is affixed in the usual manner. The use of the points is
this, that, when the blocks turn round, they will stick in the table
and assist in giving a uniform motion to the wheel. On the front of
the wheels, make four or five circles of strong wire, or flat hoops,
and tie, on these circles, as many illuminations, as they will hold,
at two inches from each other. Spiral lines may be made instead of
circles. When illuminations are fixed in a spiral line, in the front
of a wheel, they ought to be placed on the slant. The cases for these
wheels may be filled with any coloured charge, but must burn only one
at a time. A globe, or spiral wheel may be put on the spindle, so
that its fire may play over the vertical wheels. The wheels must be
lighted at the same time, and the illuminations, after two cases of
each wheel are consumed.

The vertical scroll wheel is formed by taking a block of a moderate
size, and fixing in it four flat spokes, and, on them, a flat
circular fell of wood. Round the front of this fell, port-fires are
placed; and on the front of the spokes a scroll is formed either with
a hoop or strong iron-wire. On this scroll, tie cases of brilliant
fire in proportion to the wheel, head to tail. When the first case
near the fell is lighted, the fire is communicated in succession.
The grand volute, with a projected wheel in front, is made in the
following manner: Two hoops are formed of strong iron wire, one
of six feet in diameter, and the other of four feet two inches.
These hoops must be joined to scrolls, formed according to fancy,
of the same kind of wire. On these, tie, with iron wire, as many
illuminating port-fires, as they will carry, at two inches distance.
Prepare then a circular wheel of four spokes, three feet six inches
in diameter, and, on its fell, tie as many four-ounce cases, head
to tail, as will complete the circle, only allowing a sufficient
distance between the cases, that the fire may pass free. On each
spoke, fix a four-ounce case, about three inches from the fell of
the wheel. These cases are to burn one at a time, and the first of
them to begin with those on the fell, of which four are to burn at a
time. On the front of the wheel, form a spiral line with strong wire,
on which tie port-fires, with their mouths to face the same way as
the cases on the wheel. All these port-fires must be fired with the
second cases on the wheel.

The spokes of the wheel must be formed of wood, and made to screw
into a block in the centre, and each spoke should be four feet six
inches in length. In the top of each, fix a spindle, and, in each
spindle, put a spiral wheel of eight spokes. The blocks of these
wheels must have a hole at top for the centre cases, and the spindle
must be furnished with nuts, screwed on their ends, which should fit
in the holes at the top of the blocks. The cases of these wheels
are to burn double; and the method of firing them, is by carrying a
leader from each down the spokes into the block in the centre, as in
the dodecaedron; but the centre cases of each wheel must begin with
the two last cases as usual. The large circular wheel in front ought
to have a tin barrel on its block; into which a pipe must be carried
from one of the second cases on the wheel. This pipe, being met by
another from the large block, in which the eight spokes are screwed,
will fire all the spiral wheels, and the illuminating port-fires at
the same time. The cases of the projected wheel may be filled with a
white charge, and those of the spiral wheels with a gray.

_Sec. XXI. Of the Spiral or Endless Screw, and Waved Fire._

This piece is formed in the same manner as the single and double
cones; and, in fact, is the same as the Archimedean screw, which we
have already described. The serpentine form which characterizes the
spiral piece, is given to it by the particular arrangement of the
lances of illumination. The cone receives its motion from the cases
of white-fire; the fire of which is communicated by leaders to the
cases of port-fire, or lances of illumination. They must burn the
same length of time.

The waved fire is produced by having two wheels of a similar size,
turning in a contrary direction on the same axis, and furnished with
cases, which are inclined about 45 degrees from the level of the
table. These wheels carry four cases each, and burn at the same time.
They have been made to carry forty-eight cases, and furnished, at
their centres, with lances, bent in a particular manner, so as to
represent the motion of serpents.

_Sec. XXII. Of the Decoration of Wheels._

Wheels, we have seen, may be made of different dimensions, according
to the purpose to which they are applied. The most common are three
or four feet in diameter, with a nave of hard wood, and spokes of
light wood. They are sometimes surmounted with a fell, and frequently
by several concentric hoops, placed at different distances from each
other.

Wheels, in general, are furnished with cases, and various
decorations. Some have two, three, four, and more fires; but, if they
are _finished_ too much, the weight they thus acquire would retard
the velocity of the wheel. Their centres may be finished in several
ways; as, for instance, by attaching, to the inner fells or circles,
cases filled with white lance-composition, placed at the distance of
two inches from each other, or alternately, white, blue, and yellow,
or Chinese gerbes, or cases of blue fire. We may also attach small
turning suns, the axes of which being placed upon the spokes. They
may also be made to resemble a mirror, by furnishing all the spokes
with white lances; and for the last fire, we may attach four cases to
the centre, or in its vicinity, placed in such a manner, that their
fire may issue from the interior of the wheel. To this, we may add,
two other cases, which may cross the former. Leaders are fixed, and
they are lighted at the same time.

Automatons with all their joints, or articulations, have been added
to exhibitions of this kind, and with particular effect. They are
clothed with cases after the usual manner.

_Sec. XXIII. Of Globes, with their Various Decorations._

The first we purpose to treat of are the illuminated globes with
horizontal wheels.

The hoops for these globes may be made of wood, tin, or iron wire,
about two feet in diameter. For a single globe, take two hoops and
tie them together, one within the other, at right angles; then have
a horizontal wheel made, whose diameter must be a little wider than
the globe, and its nave six inches long; on the top of which, the
globe is fixed so as to stand three or four inches from the wheel.
On this wheel may be put any number of cases, filled with any of the
ordinary charges, as the white fire composition. Two of these cases
must burn at a time. They may be placed horizontally, or inclining
downwards. When the wheel is clothed, fix on the hoops as many
illuminations as will stand, within two and a half inches of each
other, which are fastened on the hoops with small iron wire. Attach
the pipes of communication, and arrange them so as to carry the fire
to all at the same time, with the exception of one or two, which are
to receive their fire for the last. The spindle, on which the globe
is to turn, must go through the block of the wheel up to the inside
of the top of the globe; at this place must be fixed a bit of brass
or iron, with a hole in it, to receive the point of the spindle, on
which the whole weight of the wheel is to bear. When the globe is to
be stationary and the wheel to run by itself, the block of the wheel
must not be so long, or the spindle any longer than to raise the
globe a little above the wheel.

We may remark, that, while the cases of white fire composition give
to the piece a rotary motion, those of the lance or illuminating
port-fire produce the effect, which characterizes in particular this
fire-work.

With respect to fire globes, there are two kinds; namely, one with
projected cases, and the other with concealed cases. If we have a
globe made of wood, of any diameter, and divide its surface into
twenty-four equal parts, and bore a perpendicular hole in each of
these divisions to the centre, we may then represent this piece in
the following manner: In every hole, except one, put a case filled
with brilliant or any other charge, and let the mouths of the cases
be even with the surface of the globe. Then cut in the globe a groove
from the mouth of one case to that of another for leaders, which must
be carried from case to case, so that they may all be fired together.
The globe is then covered with a single paper and painted.

Fire globes with projected cases are made in the following way:
Prepare a globe with fourteen holes, and fix in every hole except
one, a case, and let each case project from the globe two-thirds
of its length. Then clothe all the cases with leaders. It must be
supported by a spindle made to fit the hole in which there is no case.

The _bursting-globe_ is nothing more than a globe prepared in a
particular way. It turns on a pivot, and is made by uniting four
segments. These segments or parts are fixed to hinges, which open on
the inside, and, when brought together, are kept in their place by a
match which goes round the globe. The globe, it is to be observed, is
furnished in the inside with several steel springs, which, unless the
globe itself were tied, would force it open. When the match is burnt,
this effect follows and the globe separates into four parts. It is
furnished with lances and cases in the same manner as those already
described. The last effect is that we have noticed.

_Globes, which leap or roll on the ground_, may be formed by
procuring a wooden globe, furnished with a cylinder; and, having
loaded it with the composition hereafter mentioned, introduce into
it four or more petards loaded with grain powder to their orifices,
which must be well stopped with paper or tow. If a globe prepared
in this manner be fired by means of a match at the mouth of the
cylinder, it will leap about as it burns on a smooth horizontal
plane, according as the petards are set on fire. The petards may be
affixed to the exterior surface of the globes, which they will cause
to roll and leap as they catch fire.

_Composition._

Grained powder, 1 lb.
Saltpetre, 32 --
Sulphur, 8 --
Scraped ivory, 1 oz.
Sawdust, (boiled in saltpetre and dried,) 8 lbs.

_Sec. XXIV. Of the Representation of the Moon and Stars._

The moon and stars are represented in the following manner: Make a
wheel eighteen inches in diameter, by fixing eight or more spokes
in the nave; and then adapt a fell to it. To the fell fasten eight
cases of the black or gray composition, and let the fire communicate
from one to the other. These cases give motion to the wheel. Furnish
the spokes of this wheel with cases charged with the white lance
composition. Make now a crescent of iron and attach it to the spokes,
or a little before the spokes of the wheel. In order to fix stars
to this piece, eight strips of wood, seven feet in length, are made
to cross each other at equal distances, and nailed to each other in
the middle; so that when this frame is put behind and secured to the
moon-piece, its arms will extend some distance beyond the perimeter
of the wheel. These projections are furnished with five-pointed
stars, eight inches apart, and there is usually in all thirty-two.
They are made to communicate with each other by means of the cotton
match, as before described. The light of the lances renders the moon
very apparent, and the fixed stars resemble those in the firmament.
The representation of the moon and seven stars may be performed by
procuring a smooth, circular board, six feet in diameter. Out of
the middle of it cut a circular piece twelve or fourteen inches in
diameter, and cover the hole formed with Persian silk, on which is
to be painted a moon's face. Also cut out of the board stars of four
or five inches in diameter. These stars are cut out with five points
and covered with oiled silk. On the front of the large circular
board draw a seven-pointed star, as large as the circle will admit,
and on the lines which form this star, make several perforations, in
which six-pointed stars are to be fixed. A wheel of brilliant fire is
placed behind the moon, which renders the moon and stars transparent.
They will disappear when the wheel is burnt out; but then in
consequence of the communication of the fire to the large star in
front, which is formed of pointed stars, the appearance of this star
succeeds, and finishes the piece.

A large fixed star may be made thus. To each extremity of the pieces
of wood, arranged so as to cross each other, attach two cases of the
black charge. Their fire must communicate. Near these cases, on each
arm, place a turning sun of three cases. These five suns are fixed at
the same time, and when they cease, the cases commence. These cases
form the star.

The representation of flaming stars, with brilliant wheels, is
made in the following manner. After procuring a circular piece of
wood, about one inch thick, and two feet in diameter, fix round it
eight points, each two feet and a half long, four of which must be
straight and four waved, or flaming. These points being joined on
very strong, and even with the surface of the wood, nail tin or
pasteboard on their edges, from the wood to the end of each, where
they must be joined. This tin is to project in front eight inches,
and be joined where they meet at the block. Round the front of the
wood, fix four pieces of thick iron wire, eight inches long each,
equally distant from each other. Cut a piece of pasteboard round,
two feet in diameter, and draw on it a star; then cut out this star,
and on the back of it, place oiled paper. Paint half red and half
yellow, lengthwise. The body of the star must be left open in which
must be seen a brilliant wheel. This wheel is formed by having a
block turned nine inches long, and fixing in it six spokes. At the
end of each spoke, put a two-ounce case of brilliant fire. The length
of these cases is made in proportion to the wheel, and the diameter
of the wheel, when the cases are on, must be less than the diameter
of the body of the small star. The cases on the spokes in front must
have their mouths inclined outwards, and those on the inside spokes,
placed so as to form a vertical circle of fire.

Carry the first leader, from the tail of one of the cases in front,
to the mouth of one of the inside cases, and from the tail of that
to another in front, and in the same order to all of them. Put on a
spindle in the centre of the star. This spindle must be furnished
with a shoulder at bottom, to keep the wheel at a little distance
from the block, which is kept on the spindle by a nut at the end.
Having fixed on the wheel, fasten the transparent star to four pieces
of wire. When fired, a common horizontal wheel will only be seen; but
when the first case is burnt out, it will fire one of the vertical
cases, which will show the transparent star and fill the large flames
and points with fire. It will then appear like a common wheel, and
represent the same appearance for twelve changes.

With respect to the formation of stars for regulated pieces, we may
remark, that they are made of different sizes according to the work
for which they are intended. They are prepared with cases from one
ounce to one pound; but, in general, with four-ounce cases, four or
five inches long. The cases should be rolled with paste, and twice
as thick of paper as a rocket of the same caliber. Having rolled a
case, let one end of it be pinched quite close; then drive in half
a diameter of clay, and, when dry, fill it with composition to two
or three inches of the length of the case. At the top of the charge,
drive some clay; as the ends of these cases, being seldom pinched,
would be likely to take fire. Divide the case, when filled, at the
pinched end close to the clay, into five equal parts; then bore
five holes with a gimblet, about the size of the neck of a common
four-ounce case, into the composition. From one hole to another,
carry a quick match, and secure it with paper, in the same manner as
the ends of wheel cases; so that the hollow part, which projects from
the end of the case, may serve to receive a leader from any other
work, to give fire to the points of the stars. These stars may be
made with any number of points.

_Sec. XXV. Of the Representation of Sundry Figures in Fire._

Animals and various figures may be represented in fire by the
following method: Take sulphur, reduced to a very fine powder, and,
having formed it into a paste with starch, cover the figure of the
thing to be represented, with this mixture, having first coated it
with clay to prevent it from being burnt. After the figure is covered
with paste, it must be sprinkled, while moist, with gunpowder; and,
when the whole is perfectly dry, arrange about it several small
matches, that the fire may be speedily communicated to it on all
sides. In this way, all sorts of garlands, festoons, and other
ornaments may be imitated by fire of different colours.

A shower of fire may be connected with this representation, by using
cases of one-third of an inch in diameter, charged with any of the
following compositions. These cases should be two inches and a half
in length. They must not be choaked, it being sufficient to twist
the end of the cartridge. The effect of these cases is to fill the
surrounding air with an undulating fire. The compositions are similar
to those already noticed; viz. for _Chinese Fire_, take gunpowder
one pound, sulphur two ounces, pulverized cast-iron of No. 1. five
ounces; for _ancient fire_, meal-powder one pound, charcoal two
ounces; and for _brilliant fire_, meal-powder one pound, and iron
filings four ounces. Sparks are also sometimes employed. These are
made in the usual manner.

Besides the common mode of forming sparks, as they differ from stars
only in their size and duration, (being formed into small balls about
the size of peas), they may be made by the following method: Take
sawdust of fir, poplar, &c. and boil it in water, in which saltpetre
has been dissolved. When the water has boiled some time, it is to be
poured off, that the sawdust may remain in the vessel. When nearly
dry, spread it out on a table, and sprinkle it with sulphur, sifted
through a very fine sieve, to which may be added a little meal-powder.

If it be required to accompany the exhibition with bearded rockets,
(_fusées chevelues_ of the French), so called from the circumstance,
that, when they fall, they make small undulations in the air like
frizzled hair, we may form them in the following manner: Fill the
barrels of some goose-quills with the composition of sky-rockets,
and place upon the mouth of each a little moist gunpowder, both to
keep in the composition, and to serve as a match. If a flying-rocket
be then loaded with these quills, they will produce, at the end, a
beautiful shower of fire.

_Sec. XXVI. Of the Representation of Flat Stars, with a large Body of
Fire._

A star of five points, about two feet from point to point, is to be
made, and, in its centre, is placed a turning sun, composed of three
cases, and altogether not more than six or eight inches in diameter.
To this star five branches are fixed, each of which is three feet in
length; and, to the extremity of each, are attached seven cases, with
their mouths outwards, and inclining about thirty-five degrees. One
case is then attached lengthwise, and forms the very extremity of
each projection. On each leg or branch, nearer, however, the centre
of the star, must be three cases, fixed in an hexangular form. The
border of the large star is decorated with Italian or fixed stars.
The fire is communicated to the star by means of a leader, then to
the sun and the cases on the branches.

_Sec. XXVII. Of the Single, Double, and Triple Table Wheel._

We have spoken of an arrangement of fire-works, which moves a wheel
on a circular board. That contrivance is similar to the one we now
purpose to describe.

The table-wheel is a kind of girandole, which turns circularly on a
round table, by having its axis connected with a perpendicular pin,
fixed in the table; so that its motion is vertical, while it moves in
a circular position round the table.

The table, as well as the wheel, may be of any size, according to
fancy. Eight or nine cases are usually attached to the fell of the
wheel, and in the direction of the fell. These cases turn it with
great velocity. The centre of the wheel may be decorated with lances,
or illuminating port-fires. When double or treble wheels are to
be arranged on the same table, this is done by having the iron so
lengthened, as to extend over the table, and receive another wheel
of the same size; and by using a contrivance of iron, having three
projections, at equal distances apart, and turning in the same manner
on a pivot, or pin, fixed in the centre of the table, three wheels
may be put in motion at the same time. When two wheels are employed,
we may decorate one with blue lances, and the other with yellow.
When three wheels form the same piece, it is usual to illuminate
them, severally, with white, blue, and yellow lances. The wheels of
coloured fire augment the beauty of the exhibition. In the centre of
the table, may be placed a pyramid, decorated in the usual manner.
Spiral wheels, globes, &c. may be attached, if so required.

_Sec. XXVIII. Of Decorations, Transparencies, and Illuminations._

Cut-work, as it is called, is often employed in decorations. Various
figures, letters, garlands, &c. may be represented. This may also
be accomplished in tambour-work. Several methods have been used
to produce the same effect. Cut-work, made in pasteboard, and the
pasteboard blackened and suspended in a frame, will, by the aid of
lights placed behind it, exhibit the design very perfectly. A figure
of a sun cut out of pasteboard, either fixed or made to revolve in
the manner before described, and illuminated by fixed lights or
revolving cases, is considered to be the best mode of forming such
pieces. In all instances, the more brilliant the fire, the more
perfect is the representation. Tambour decorations are variously
arranged; and, frequently, in the termination of an exhibition, six
or more are shown at once, and sometimes with cascades, and turning
suns.

In the place of cut-work, painted transparencies, made with fine
colours, and on Florence Taffeta, are usually employed. Transparent
paintings however, are not preferred by some, as the effect, it is
said, is not so perfect as when cut-work is employed. Morel gives a
preference to the latter.

Transparencies may be formed with silk, or fine linen, and even with
paper, if previously prepared, by means of the spirit of turpentine.
The colours are painted in turpentine, and transparent varnish is
then applied.

Transparent screens may be prepared, by spreading white wax,
dissolved in spirits of turpentine, over thin muslin. A screen,
thus prepared, will roll up without injury. A clearer screen may be
produced, by having the muslin stretched upon a rectangular frame,
and prepared with turpentine instead of wax.

In the _Œuvres de Diderot_, t. xv, p. 349, are observations
respecting transparencies, and the manner of preparing them. The
process described is nothing more than we have noticed. It consists
in using the oil of turpentine, and sometimes a solution of wax
in turpentine. The colours are prepared mostly with turpentine.
Canada balsam, thinned by the addition of the spirit, is also
employed. Moveable transparencies were exhibited with great effect
in Paris. Transparent figures were made to move continually in every
direction, which had a singular appearance. Artificial fire-works
were very accurately imitated, by producing a variety of movements
with different pieces of transparencies, variously coloured. The
sun, moon, and stars, revolving wheels, &c. composed a part of this
exhibition.

With respect to decorations in white and coloured lances, we may
observe, that artificial fire-works are usually terminated by some
decoration, which corresponds with the subject. For this purpose,
triumphal arches, fronts of palaces, colonades, rocks, &c. are
formed, and represented in wood-work. These are usually clothed, and
painted in water-colours. From the rocks, water is made to issue,
forming cascades, and a number of figures are put in motion. The
jets of water are terminated by jets of Chinese fire, or brilliant
fire-rain.

The furniture, or decorations, may be various, either with white or
coloured lances of illumination, hung four inches apart, and attached
to different parts of the figure, or building. If it is in front of
a temple, the columns are ornamented with emblems, &c. the fire-work
being thus arranged: _viz._ blue lances are attached to the columns,
white lances to their entablature, and to the emblems, yellow lights.
This however, depends on taste.

Decorations are also made with matches; but this mode is not
preferred, because so much smoke is thereby produced.

Figures, cut in paper, are illuminated in the manner before
described. But for this purpose, muslin is first stretched on a
frame, and its sides are covered with two or three thicknesses of
paper, which are pasted on. It is then blackened. After tracing the
design, or the subject of the illumination, and cutting it out with
exactness, the frame is put in a case, sufficiently deep to contain a
number of lights.

Illuminations, as an expression, of public feeling for some event or
memorable occasion, are by no means a recent thing. Various modes
have been adopted to render such exhibitions more elegant, as well as
more expressive. Hence, with the usual display of lights, arranged
according to taste and fancy, transparencies, decorations, such as we
have described, &c. have been more or less customary.

We mentioned, in the first part of our work, something in relation
to the antiquity of illuminations; but, as this subject may be
interesting, we deem the following brief remarks not irrelevant.

Beckman assures us, (_History of Inventions_), that the origin
of illuminations is very ancient. The feasts, or holy-days were
celebrated in the days of antiquity, in various ways, among which,
that with lamps was very common in Egypt. It was called the feast
of the lamps, (_Fête des Lampes_), and the inhabitants of some
cities in Egypt were obliged to illuminate, with a great number of
lamps, placed before their houses. Herodotus (_lib._ ii, _chap._
62), remarks, that, at a particular festival of the Egyptians, lamps
were placed before all the houses throughout the country, and kept
burning the whole night. During the _festum encæniorum_, the Feast
of the Dedication of the Temple, which, according to common opinion,
was celebrated in December, and continued eight days, a number of
lamps were lighted before each of their houses. Such illuminations
were used, also, in Greece and Rome, and were called _Lampadaria_.
An infinite number of lamps were burnt in honour of Minerva, Vulcan,
Prometheus, Bacchus, &c. On the last occasion, the illumination was
called _Lamptericæ_. It seems that the lighting of streets had not
been adopted at that period.[25] At Rome, the forum was lighted,
when games were exhibited in the night-time; and Caligula, on a
like occasion, caused the whole city to be lighted. As Cicero was
returning home late at night, after Cataline's conspiracy had been
defeated, lamps and torches were lighted in all the streets, in
honour of that great orator. The emperor Constantine caused the
whole city of Constantinople to be illuminated with lamps and wax
candles on Easter-eve. The first christians often illuminated their
houses on idolatrous festivals, in a more elegant manner than the
heathens. This was dictated by policy. The houses of the ancients
were illuminated on birth-days, by suspending lamps from chains.

For illuminations at the present day, tallow is chiefly used. It is
clarified, for the making of candles, by means of alum. M. Olaine
in 1710 presented to the academy of sciences an apparatus for the
manufacture of candles. The _bougie economique_ of the French is
described in the _Journal de Paris_ for 1782. The outline of the
process for preparing them is as follows: Take eight parts of suet,
and melt it with one quart of water; and after straining it, and
returning it to the same boiler, add the same quantity of water, in
which was dissolved half an ounce of saltpetre, as much sal ammoniac,
and one ounce of alum. The boiling is continued to evaporate the
water. The wick is made of cotton or flax, and rolled in a solution
of camphor in petroleum, and afterwards covered in the usual manner
with the above composition.

In using tallow generally, quicklime is recommended to be added to
it in fusion. When the quicklime subsides, it is poured off. Another
mode recommended is to melt the tallow with vinegar, and to add to
it a decoction of rosemary, sage, laurel, and a small quantity of
turmeric; the whole being boiled until the water is evaporated. This
communicates, it is said, an agreeable odour, and a yellow colour.
Different modes of preparing tallow for candles have been used.
See _sal ammoniac_. With respect to ancient lamps, some account of
them has been published in the _Antiquities_, by Montfaucon and by
Passeri; and the _Journal des Savants_ 1682 and 1685 mentions the two
lamps of Boyle and Sturmius, and some account of the celebrated lamp
of Callimacus in the temple of Minerva. On the formation of lamps,
and the purification of oil, sundry patents have been granted both
in France and England. The argand lamp for burning its own smoke,
which it effects by a glass cylinder placed over the flame, is one
of the best improvements of the kind. The principle of these lamps
is the same, although variously modified in shape and structure. For
chemical purposes, an iron cylinder is substituted for glass. A lamp,
for the burning of tar and turpentine, with steam, has lately been
invented by Mr. Morey, (_see Silliman's Journal Vol. II._) Mr. E.
Clarke obtained a patent for a lamp calculated to burn tallow; the
principle of which is, that by the heat of the flame, the caloric
is conducted to the tallow by means of a piece of iron, which is
heated by it, and the tallow melts as it is wanted. This lamp may be
economically used, when common lamp oil is scarce and high in price.
A lamp is described in the _Repository of Arts_, to burn tallow.

As a wick, besides cotton, several substances have been recommended.
The filaments of amianthus, for instance, while they perform the
office of a wick, are incombustible. The _Journal de Verdun_ for
1748, announced incombustible wick by sieur Lespar. Touch wood, the
_tussilago sarfara_, and the _verbascum tapsus_ of Linnæus, are
also recommended. In 1783, Leger announced, in the _Journal de la
Blancherie_, that he had invented a match which would burn without
smoke and odour.

Lamps have been furnished with fixed and moveable mirrors, to throw
the light forward by reflection. The reverberatory lamps, revolving
lights for light houses, &c. are of this kind. Many patents have been
obtained for such contrivances, which we have not room to notice.

The inflammable air lamp for the table, described in the
_Dictionnaire de l'Industrie_, is nothing more than a spirit of
wine lamp, and used in lieu of hot bricks, or vessels filled with
boiling water for the warming of dishes, &c. In 1780, M. Ehrman, in
his _Description et usage de quelques lampes à air inflammable_,
describes a chafing dish with inflammable air, invented by Nevet,
which operates by the combustion of hydrogen gas.[26]

Fixed illuminations are more brilliant and more magnificent; as
the lights are more numerous, as well as more diversified. Wax,
spermaceti, or tallow candles, or oil burnt in tin lamps, or in glass
cups suspended by wire, are all used for the purpose. If the wick be
dipped in spirit of turpentine, it will take fire instantaneously. It
is unnecessary to make any remarks as to the arrangement of lights.

Large dishes containing melted tallow, and a wick proportionally
thick and suspended by means of a simple contrivance of tin, are
recommended for the same purpose. Coloured lights afford a variety.
The appearance of coloured flame may be produced by burning the oil
in coloured glasses, so disposed as to let the light pass through
the glass, or by placing lamps behind bottles filled with coloured
water.[27]

The coloured glasses which are sold in Paris for the purpose, are
formed with facets on the outside, which not only produce the
appearance of coloured flame, but also, according to the number of
facets, the refraction and reflection of the light. Arches, pyramids,
obelisks, &c. are lighted up in this manner.

The Pont Neuf, and the Seine in 1739, were illuminated at the
time of the splendid exhibition of fire-works. It is unnecessary,
however, to particularize on this head. We all remember the splendid
illuminations in all our cities during the late war, which were
indeed a true expression of our national and individual feeling.
Illuminations, in this country, before that time were very rare; none
we think since the peace of 1783, and the union under the federal
compact.

Phosphuret of lime, of the size of peas, thrown into water, will
afford, at short intervals, a brilliant flame of fire; for the
phosphuretted hydrogen gas thus produced has the property of
inflaming spontaneously in atmospheric air. Alcohol, containing
sundry salts in solution, will give a flame of various colours,
according to the salt it holds in solution. See _Alcohol_.

Illuminated works are much admired by the Italians, and particularly
the _Illuminated chandelier_, which is considered a great addition
to a collection of works. An illuminated chandelier is formed of
thin wood with arms extending on each side. Holes are bored in the
front of the branches and in the body, and also in the eagle (if it
be added,) at top, and distant from each other about three inches.
In these holes, we put illuminations, filled with white, blue and
brilliant charge. Having fixed in the port-fires, they must be
clothed with leaders, so that the chandelier and eagle may light
together.

We may also observe, that, for the speedy lighting of a number of
lamps, at one and the same time, quick-match enclosed in paper tubes
has been used. This quick-match is sometimes made to communicate
its fire to a sulphur match, prepared by dipping strands of cotton
in melted sulphur, and from this to the lamp. Several methods are
recommended for this purpose; one of which consists in dipping
cotton wick in the oil of spike, and arranging it along the wicks
of the different lamps, so that when inflamed the fire may pass
rapidly from one lamp to another. In 1772, M. Renault, a Parisian,
announced in the public papers, that he possessed a secret, by which
he could light 2000 lamps in five minutes, by means of a match of
communication.

We have some experiments and observations on coloured flame, by
Mr. Morey, in his essay on heat and light, in the second volume of
Silliman's _Journal of Science and Arts_, p. 120. The experiments are
curious, and worthy of remark. If water, he observes, be put into
one cylinder, and made to boil, and the steam be led to the bottom
of another included cylinder, containing spirits of turpentine, the
steam, when let out under a moderate pressure, carries off with
it a sufficient quantity of the spirit to burn with a pleasant
_white_ flame, free from smoke; but if the pressure be increased,
the flame will become in part or wholly blue. "Here," he adds, "as
in many other experiments, I have noticed, that different coloured
flames may be produced from the same materials--are the products
of combustion different?" He further observes, that "if the steam
of water, containing a small proportion of the vapour of rosin, be
driven against iron, at or below a red heat, it burns with a pleasant
_blue_ flame, which will be extended some way back into the column
of the vapour, intermixed with innumerable sparks of very white
flame, evidently particles of the rosin. If the vapours, when the
proportion of the rosin is very small, are made to pass between two
plates of iron, at or near a red heat, they can be inflamed on the
opposite sides of the plates, and will then, sometimes, burn with
an entirely _blue_ flame, although the vapour can not be inflamed,
without the intervention of the plates." He states other experiments,
made with tallow and steam, producing a _blue_ flame. The _blue_
colour seems to be owing to the pressure made use of; for, in his
second communication, (page 122, of the same volume), he mentions
white flame being produced by the vapour of water; and when it is in
a sufficient quantity, there is _no smoke_. If too great, combustion
ceases. Speaking of the colour of the flame, produced by mixed
vapours, (of the combustible and water), such as blue, blue and
white, white and intense white, he adds, that they may be imitated,
at pleasure, with the patent lamp stove, by burning tar, pitch pine,
or mineral coal and water. Newly made charcoal will take up about
three times its weight of water. "Sand, ashes, or fine clay," he
observes, "answers well for mixing with the tar, &c. If the latter
be made into a paste with equal parts of spirit of turpentine and
water, and cold lumps of it, of a conical form, be placed on a table,
and a flame applied, the vapours burn without smoke for a short
time, &c. If enclosed in a tin cylinder, and the vapour be made to
issue through small holes at the top, placed as before stated, or on
a plate over a chafing dish of coals, it burns with a very bright
light, free from smoke. If the cylinder be tight at the top and
the vapour be led from the inside at the top, down and through the
bottom, and there be made to issue in an oblique direction, and from
a number of small openings, it will burn with a beautiful flame and
supports and regulates, very accurately, its own evaporation. The
oblique direction carries the heat, in part, beyond the cylinder,
when the evaporation is too great.

"Every effect may be produced in consuming the smoke, and giving
an intense white flame, by using a certain proportion of water,
intimately blended or mixed with these vapours, that can be from an
access of oxygen furnished, by creating a very strong current of
air, with a high flue." The description of Morey's lamp stove, may
be seen in the same work. The steam, he observes, may be furnished
by a small tin boiler, and directed to or near the bottom of the
tar. An _intense white flame free from smoke_, may be thus produced
from tar, rosin, rough turpentine or the spirit, alcohol, oil,
fat, tallow, mineral coal, pitch pine wood, and the knots, birch
bark, and pumpkin, sun-flower, flax, and other seeds. With regard
to pine wood, he adds, it is the easiest managed, evaporates at a
lower temperature, consumes a greater proportion of water in its
combustion, contains the water within itself, and gives a brighter
light than common candles or lamps, and without smoke. The more
volatile parts are evaporated at a temperature below that of boiling
water, and burn well with three parts of the vapour of water;
the flame then, however, is nearly _blue_. Observations on the
application of this mode of producing light and heat, may be seen
in Silliman, p. 131, &c. It appears, that Gay-Lussac (_Annales de
Chimie_, for June, 1819,) has commented on Mr. Morey's plan.

Professor Hare (_Silliman's Journal_, vol. 2d, p. 172) also observes,
that the flame of hydrogen gas is rendered luminous, like that of
oil, by adding a small quantity of oil of turpentine to the usual
mixture for generating this gas; and that the addition of 1/17 of
the same fluid to alcohol, will give it the property of burning
with a highly luminous flame; and there is a certain point in the
proportions, at which the mixture burns without smoke, like a gas
light. In the first instance, he observes, when the ingredients are
at the proper temperature, the light is greater than that produced by
carburetted hydrogen gas. Speaking of this application of spirits,
the professor judiciously adds: "It might be serviceable to _morals_,
if the value of this article could be enhanced by _a new_ mode of
consumption." We find, also, that the effect of vapour on flame has
been noticed by Dr. Dana, in the same Journal, vol. 1, p. 40; by
which it appears, that when a jet of steam is made to pass into a
charcoal fire, the vividness of the combustion is increased, and
also the low attenuated flame of the coal; that it prevents the
smoke of a common oil lamp, and makes the flame brighter; that the
flame of spirit of turpentine, which is usually dull and reddish, is
rendered bright, and no smoke is formed; or when the vapour of both
are made to issue together from the same orifice, and inflamed, no
smoke appears; that a jet of steam, thrown into the flame of a spirit
of wine lamp, or into flames which evolve no smoke or carbonaceous
matter, produces the same effect as a current of air; but that, in
all flames which evolve smoke, steam produces an increased brightness
and a more perfect combustion. Dr. Dana further suggests, that steam
might be introduced into the flames of street lamps, which might be
so contrived as to keep water boiling, to produce the steam, and
thereby cause a more perfect combustion, and a greater quantity of
light from the same materials.

Count Rumford has shown, that the quantity of light, emitted by a
given portion of inflammable matter in combustion, is proportional,
in some high ratio, to the elevation of temperature; and that a lamp,
having many wicks near each other, so as mutually to increase their
heat, burns with infinitely more brilliancy than the Argand lamps in
common use. To measure the proportional intensities of two or more
lights; place them a few inches asunder, and at the distance of a
few feet or yards from a screen of white paper, or a white wall. On
holding a small card near the wall two shadows will be projected on
it, the darker one by the interception of the brighter light, and the
lighter shadow, by the interception of the duller light. Bring the
fainter light nearer to the card, or remove the brighter one further
from it, till both shadows acquire the same intensity. Measure now
the distances of the two lights, from the wall or screen, square
them, and you have the ratio of illumination. Thus, if an Argand
flame and a candle, stand at the distances of 10 feet and 4 feet,
respectively, when their shadows are equally deep, we have 10^2 and
4^2, or 100 and 16, or 6-1/4 and 1, for their relative quantities of
light.

The author of the _Dictionnaire de l'Industrie_, vol. iii, p. 365,
in treating on the subject of illumination, mentions different modes
of illuminating, both with and without transparencies. We know that
various mixtures will produce different coloured flame. Thus, arsenic
will burn with a beautiful white flame in oxygen gas; iron and steel
will burn also, affording a brilliant light; phosphorus and charcoal
with a white, and sulphur with a beautiful blue flame; zinc with a
green colour, &c.

Again, we know that a mixture of nitrate of strontia and charcoal
will burn with a rose coloured flame; one part of boracic acid, and
three of charcoal, with a green flame; one of nitrate of barytes, and
four of charcoal, with a yellow flame; and equal parts of nitrate of
lime and charcoal powder, with an orange flame. We also know, that
cotton dipt in oil of turpentine, or ardent spirit, rosin, camphor,
&c. will burn extremely vivid and beautiful.

The author, whom we have just quoted, gives some remarks on the
various coloured flames, that may interest the reader.

_Felt_ (_Feutre_, Fr.) he remarks, if put in the fire, will give
most beautiful colours, a golden yellow and a brilliant blue. And
this, he adds, may be proved by throwing pieces of old hats into the
fire; for these colours depend on the substances used in dying the
hat. He further remarks, that green oak wood gives a yellow flame,
and alcohol with sedative salt, (boracic acid), a blue, and that, by
uniting the flame of both, the product, as to colour, will be a green.

The flame of alcohol is changed of various colours, according to the
salt it holds in solution. Of this circumstance, Schatt was apprised,
when he gave some formula many years ago, on the manner of forming
coloured flame. Reaumur remarked also, the different colours which
some metals assume, when submitted to the action of heat, which is
known now to be the effect of oxidizement.

As respects the phenomena with felt, we are told, that, if we throw
into the fire the cuttings of hats, we will perceive at first a
white flame, and then in succession a blue, green, and violet colour;
all which, our author observes, proceeds from the verdigris and other
substances, employed in the composition of the dye stuff. There is
one fact, which he has asserted, which may probably be explained on
the _materiality_ of light, so far as regards the _formation_ of
colour, (not considering, however, the theory of Bancroft, given in
his _Philosophy of Permanent Colours_, or the more philosophical one
of Dr. Samuel Conover, of Philadelphia, in the Transactions of the
_American Philosophical Society_), and this fact is, that the flame
carries the colour to the object which it illuminates, and that the
object itself actually partakes of the colour, in order to produce
any particular appearance. That colours, as visible to the eye, are
all formed in the solar light, and their appearance depends upon the
_absorption_ of some of the rays of light, and the _reflection_ of
others, is a doctrine which followed the discoveries of Sir Isaac
Newton. We have not room to notice this subject, however interesting
it may be in a philosophical point of view.

There can be no doubt, that the art of colouring flame was known
for a long time. We are told, that the philosopher Anaxilaus even
pretended, that, by putting ink with the oil of a lamp, or the liquor
of the cuttle fish, the faces of the bystanders will appear _black_
by the light of this lamp! Sulphur has the effect of rendering the
visage pale and cadaverous. Other persons, as Simon Sethe, advanced
an opinion, that, if we moisten the wick of a lamp with ink, or in
a mixture of the rust of copper, and having lighted the wick, and
placed other lights around it, the faces will appear, some black,
and some of a brass colour. Others, such as Cardan, say, that, by
making a mixture of wine and salt, and then reducing it two-thirds
by evaporation, the flame, which the wine will then give, will make
the _living_ put on a cadaverous appearance, if they remain in one
posture. Malina also observes, that, by burning a piece of woollen
cloth well soaked in a solution of salt in vinegar, the visage will
appear frightful by the light of the flame. But the process of J. B.
Porta is not less worthy of note. If good old wine, he observes, be
put into a bowl with a handful of salt, and set on live coals, but
not in the flame, and as soon as it begins to boil, is set on fire,
(the other lights in the room being extinguished), the figure of each
person will appear so hideous, as to produce a mutual dread. The
author of the _Dictionnaire de l'Industrie_, iii, p. 433, observes,
that he has repeated this experiment, sometimes with brandy, and at
other times with alcohol, with perfect success.

A cadaverous appearance is said to be given, by mixing common salt
with alcohol, in which some saffron had been infused. When set on
fire, and the other lights extinguished, the effect, we are told, is
very striking.

The so called _miraculous luminaries_, are nothing else than solar
phosphori, which are very numerous. Their effect is to emit light in
the dark, but not heat. Almost every thing in nature possesses this
property in a greater or less degree, which depends on the absorption
and subsequent transmission of light. The eyes of various animals
have this property; cats and owls in particular. Snow possesses it
in a considerable degree. Putrid animal matter, fish, for example,
rotten wood, &c. partake also of this property.

It may not be improper to notice, in a general way, some of the
substances, which are denominated solar phosphori. The _Bolognian
phosphorus_ is the calcined baroselenite, (sulphate of barytes),
which, when exposed a few minutes to the light, shines when taken
into the dark like burning coals. In water it emits the same light.
This property, as is the case with all other solar phosphori, it
loses gradually; but by heating it again, imbibes light. _Canton's
phosphorus_ is calcined oyster shells. It is used in the same manner.
_Baldwin's phosphorus_ is fused nitrate of lime. Various saline
and other bodies, as diamonds and precious gems, possess the same
property. Expressed oils and animal fats, when heated to 450°, become
phosphorescent.

Hanzelet (_Traité des Feux d'Artifice_) remarks, that a _stone_ may
be made to give light by water, if prepared in the following manner.
Take quicklime, tutty, and saltpetre, of each one part; reduce them
to powder, and expose them to the action of heat. On the addition of
water, light is said to be given out.

When quicklime is mixed with essential oil, and brought in contact
with water, spontaneous combustion is said to take place.

Fluor or Derbyshire spar, (fluate of lime), when pulverized and
heated to 212° Fahr., and then removed to the dark, is very luminous.
If writing be made on a copper or iron plate, with thin mucilage or
white of egg, and powdered fluor spar, sprinkled on it; when the
plate is removed to a gentle coal fire, the delineated objects will
become luminous, and opaque again when the plate becomes cold. The
lapis lazuli has the same effect.

The phosphoric substances, which become luminous by attrition or
percussion, are numerous. _Homberg's phosphorus_, which is nothing
more than calcined muriate of lime, is of this character. When struck
it emits light. Without either light or fire, a number of bodies will
give out light. Flints, and other siliceous stones, struck against
one another, appear luminous in the dark. Various other minerals have
the same property. Wedgwood (_Phil. Trans._ 179,) Coates (_Nich.
Jour._ 1799,) Westrumb (_Crell's Chem. Annals_, 1784,) have written
on this subject; to which enumeration we may add the interesting
remarks of Dr. Hulme, (_Phil. Trans._ 1800,) and the observations of
Cabarris, in his Memoir, read before the National Institute.

It may be sufficient to remark, that the shell-fish called _pholas_;
the _meduca_ phosphorea, and other _molluscsæ_; several insects of
the species _fulgora_, or lantern-fly; the _lampyris_, or glowworm;
the _scolopendra electrica_; the _cancer fulgens_; the medullary
substance of the human brain, &c. are all phosphorescent.

M. Dessaignes (_Bulletin de la Société Philomatique, Octobre_, 1810)
made a number of experiments on solid, liquid, and aeriform bodies,
relative to the disengagement of light by compression. Among other
conclusions, he adds, that water is the cause of the spontaneous
phosphorescence of bodies, such as quicklime, Canton's phosphorus,
dry muriate of lime, &c. all which, when brought in contact with
water, emit light, which he attributes to the consolidation of that
fluid. The absorption of moisture, and its subsequent consolidation,
may, in some instances, give rise to luminous appearances.

The _lapis solaris_, Bolognian stone, or the present sulphate
of barytes, was discovered in 1602, by Casciorolus, a shoemaker
of Bologna. He came to Scipio Begatello, who at that time was
particularly known by his attachment to the art of gold-making, and
showed him this stone, under the mystical name of _lapis solaris_,
on account of its attracting the _golden_ light of the sun, and its
boasted fitness for converting the _semi-metals_ into gold, the _sol_
of the alchemists!

Dr. Brewster (_Edinburgh Philosophical Journal_) made a number
of experiments on the colour and intensity of light, evolved by
different minerals, by which it appears, that the yellow sulphate of
barytes gives a pale light, while fluate of lime, a blue and green
light. Cellini (_Treatise on Jewelry_, published near the beginning
of the 16th century) was the first who observed the phosphorescence
of minerals; it does not appear that he knew of the Bolognian
stone. Grimshire (_Nicholson's Journal_, 8vo. vols. 15, 16, 19,)
made a number of experiments on the emission of light by bodies,
when subjected to the electrical influence; and, when thus treated,
sulphate of barytes gave a brilliant green light.

The _cawk_ of the miners, as it is also a sulphate of barytes,
phosphoresces when previously exposed to heat.

There are two water fountains, both set in motion by the action
of heat on confined air, which, as it expands, forces the water
from an under vessel in jets. The first is called the _illuminated
fountain_, and plays when the candles are lighted, stopping when they
are extinguished. The other is a fountain, which acts on the same
principle, but by the heat of the sun. The effect of the first is
more or less considerable according to the pressure of the air upon
the water, and consequently, to the degree of rarefaction which the
air undergoes.

The _chemical illumination_ of some writers, by using oil of vitriol,
iron filings, and water, and inflaming the vapour as it proceeds from
a bottle, is nothing else than the inflammation of hydrogen gas. The
"white vapours," which they describe, is the gas in question.

Having noticed the use of candles and lamps for illumination, we
purpose, in concluding this article, to give the result of some
experiments on the relative intensities of light, and duration
of different candles, made by Dr. Ure, which we extract from his
_Dictionary of Chemistry_.

----------+----------+---------+----------+---------+---------+---------
Number | Duration | Weight | Consump. | Propor- | Economy | Candles
in a | of a | in | per hour:| tion of| of |equal one
pound. | candle. | grains. | grains. | light. | light. | argand.
----------+----------+---------+----------+---------+---------+---------
10 mould | 5 h. 9 m.| 682 | 132 | 12¼ | 68 | 5.7
10 dipped | 4 36 | 672 | 150 | 13 | 65½ | 5.25
8 mould | 6 31 | 856 | 132 | 10½ | 59½ | 6.6
6 do. | 7 2½ | 1160 | 163 | 14⅔ | 66 | 5.0
4 do. | 9 36 | 1787 | 186 | 20¼ | 80 | 3.5
Argand | | | | | |
Oil Flame | | | 512 | 69.4 | 100 |
----------+----------+---------+----------+---------+---------+---------

The doctor remarks, that 1/8th of a gallon of good seal-oil, weighs
6010 gr. or 13 and 1/10th oz. avoirdupois, and lasts, in a bright
argand lamp, 11 hours 44 minutes. The weight of oil it consumes per
hour, is equal to four times the weight of tallow in candles, 8 to
the pound, and three and one-seventh times the weight of tallow in
candles, 6 to the pound. But its light being equal to that of 5 of
the latter candles, it appears, from the above table, that 2 lbs.
weight of oil, in an argand, are equivalent, in illuminating power,
to three pounds of tallow candles. The larger the flames in the above
candles the greater the economy of light.[28]

_Sec. XXIX. Of Imitative Fire-Works._

Imitative fire-works are nearly of the same character as the
transparencies and illuminations mentioned in the last section; but,
as this subject may be interesting to some of our readers, we thought
proper for that reason to appropriate a section to its consideration.

Imitative fire-works are formed in the following manner: Take a
paper that is blacked on both sides, or instead of black, let it be
coloured on each side with a deep blue, which will be still better
for such as are to be seen through transparent papers. It must be of
a proper size for the figure intended to be exhibited. In this paper,
cut with a pen-knife several spaces, and with a piercer make a great
number of holes, rather long than round, and at no regular distance
from each other.

To represent revolving pyramids and globes, the paper must be cut
through with a pen-knife, and the space cut out between each spiral
should be three or four times as wide as the spirals themselves. They
must be so cut, that the pyramid or globe may appear to turn on its
axis. The columns that are represented in pieces of architecture, or
in jets of fire, must be cut in the same manner as if they are to be
represented as turning on their axis.

In like manner may be exhibited a great variety of ornaments,
cyphers, and medallions, which, when properly coloured, cannot fail
of producing a most pleasing effect. There should not be a very great
diversity of colours, as that would not produce the most agreeable
appearance.

When these pieces are drawn upon a large scale, the architecture or
ornaments may be shaded; and to represent different shades, pieces of
coloured paper must be pasted over each other, which will produce an
effect that would not be expected from transparent paintings. Five or
six pieces of paper, pasted over each other, will be sufficient to
represent the strongest shades. To give these pieces the different
motions they require, we must first consider the nature of each
piece: if, for example, we have cut out the figure of the sun, or
of a star, we must construct a wire wheel of the same diameter with
those pieces. Over this wheel a very thin paper is to be pasted,
on which is drawn with black ink the spiral figure. The wheel thus
prepared, is to be placed behind the sun or star, in such a manner
that its axis may be exactly opposite the centre of either of those
figures. This wheel may be turned by any contrivance.

Now, the wheel being placed directly behind the sun, for example,
and very near to it, is to be turned regularly round and strongly
illuminated by candles placed behind it. The lines that form the
spiral will then appear through the spaces cut from the sun, to
proceed from its centre to its circumference; and will resemble
sparks of fire that incessantly succeed each other. The same effect
will be produced by the star, or by any other figure, where the fire
is not to appear as proceeding from the circumference to the centre.

These two pieces, as well as those that follow, may be of any size,
provided we observe the proportion between the parts of the figure
and the spiral, which must be wider in large figures than in small.
If the sun, for example, have from six to twelve inches diameter,
the width of the strokes that form the spiral need not be more than
one-twentieth part of an inch, and the spaces between them that form
the transparent parts, about two-tenths of an inch. If the sun be two
feet in diameter, the strokes should be one-eighth of an inch, and
the space between, one quarter of an inch; and if the figure be six
feet in diameter, the strokes should be one-fourth of an inch, and
the spaces, five-twelfths of an inch. These pieces have a pleasing
effect, when represented of a small size; but the deception is more
striking when they are of larger dimensions.

It will be proper to place these pieces, when of a small size, in a
box quite close on every side, that none of the light may be diffused
in the chamber; for which purpose it will be convenient to have a tin
door behind the box, to which the candlesticks may be soldered, and
the candles more easily lighted.

The several figures cut out should be placed in frames, that they may
be put alternately in a groove in the forepart of the box, or there
may be two grooves, that the second piece may be put in before the
first is taken out.

The wheel must be carefully concealed from the eye of the spectator.
Where there is an opportunity of representing these artificial fires
by a hole in the partition, they will doubtless have a much more
striking effect, as the spectator cannot then conjecture by what
means they are produced.

It is easy to conceive, that, by extending this method, wheels may
be constructed with three or four spirals, to which may be given
different directions. It is manifest, also, that, on the same
principle, a great variety of transparent figures may be contrived,
which may be all placed before the same spiral lines.

In representing cascades of fire, it is necessary to observe, that,
in cutting out the cascades, care must be taken to preserve a natural
inequality in the parts cut out; for if to save time, all the holes
are made with the same pointed tool, the uniformity of the parts will
produce a disagreeable effect.

To produce the apparent motion of these cascades, instead of drawing
a spiral, a slip of strong paper is to be provided, in which there
must be made a great number of holes near each other, and made with
pointed tools of different dimensions.

At each end of the paper, a part, of the same size with the cascade,
must be left uncut; and towards those parts the holes must be made a
greater distance from each other.

When the cascade that is cut out is placed before the scroll of paper
just mentioned, and it is entirely wound upon the roller, the part
of the paper that is then between, being quite opaque, no part of
the cascade will be visible; but, as the wheel is turned gently and
regularly round, the transparent part of the paper will give to the
cascade the appearance of fire that descends in the same direction;
and the illusion will be so strong, as to appear as a real cascade of
fire.

CHAPTER XI.

OF AQUATIC FIRE-WORKS.

Fire-works, which are exhibited on water, have a very pleasing
effect. Water rockets, in particular, are much admired.

_Sec. I. Of Water Rockets._

Water rockets are generally small, from four ounces to two pounds.
When large, they are difficult to be kept above water without a cork
float. When this is used, it is tied to the neck of the case. They
will not dive as well with as without floats.

The cases for water rockets are made in the same proportion as for
sky-rockets, but the paper is thicker. For those which are driven
solid, put in at first a ladle full of slow-fire, and then two of the
proper charge, and on that, one or two ladles of sinking charge; then
the proper charge, then the sinking charge again; and so on till the
case is filled within three diameters. Then drive on the composition
one ladleful of clay, through which make a small hole to the charge.
Fill the case within half a diameter with corn powder, on which turn
down two or three rounds of the case in the inside; then pinch and
tie the end very tight. Having thus filled the rockets, dip their
ends in melted rosin or sealing wax, or secure them with grease. When
they are fired, six or eight may be thrown in at once; but if they
are all to swim or sink at the same time, they must all have an equal
quantity of composition and be fired together.

In the rockets which burn in the water, there must be a considerable
variation in the construction of the mould, and also in the materials
of which they are composed. The composition should consist of three
materials mixed together, _viz._ three ounces of meal-powder, one
pound of saltpetre, and eight ounces of sulphur. If the rocket is
to appear on the water with a beautiful tail, the composition must
consist of eight ounces of gunpowder, one pound of saltpetre, eight
ounces of sulphur, and two ounces of charcoal. When the composition
has been prepared according to these proportions, and the rocket
been filled, apply a saucisson to the end of it, and having covered
the rocket with wax, pitch, &c. as before mentioned, attach it to a
small rod of white willow, about two feet in length, that the rocket
may conveniently float. Cork may be used, as we observed, for the
same purpose. A certain quantity of meal-powder, without any mixture,
put at certain distances, must be used, if it is required that these
rockets should plunge down and again rise up.

_Sec. II. Of Pipes of Communication._

The pipes of communication which are used under water, must be made
of thick paper, and when dry covered with drying oil, which must
then be thoroughly dried. In oiling them leave about one and a half
inches dry for joints; as the parts would not adhere where the oil
was applied. The whole, however, is completely oiled after the
leaders are joined, and the paste dry. These pipes will remain under
water for some time without injury.

_Sec. III. Of Horizontal Wheels for Water._

An octagon wheel is to be provided, made of flat boards eighteen
inches in diameter, so that the length of each size will be near
seven inches. In all the sides, cut a groove for the cases to lie
in. Procure a wooden bowl without a handle, and on the top nail the
wheel; then take four eight-ounce cases, filled with a proper charge,
each about six inches in length. When the wheel is to be clothed with
these cases, get some whitish-brown paper, and cut it into slips of
four or five inches broad, and seven or eight long. These slips being
pasted all over on one side, take one of the cases, and roll one of
the slips of paper about one and a half inches on its end, so that
there will remain about two and a half inches of the paper hollow
from the end of the case. This case is to be tied on one of the
sides of the wheel, near the corners of which holes must be bored,
through which the pack thread is put to tie the cases. Having tied on
the first case at the neck and end, put a little meal-powder in the
hollow paper; then paste a slip of paper on the end of another case,
the head of which put into the hollow paper of the first, allowing
a sufficient distance from the tail of one to the head of the other
for the pasted paper to bend without tearing. The second case is to
be tied on in the same manner as the first, and so on with the rest
except the last, which must be closed at the end; unless it is to
communicate to any thing on the top of the wheel, such as fire-pumps,
or brilliant fires, fixed in holes cut in the wheel, provided they be
not too heavy for the bowl.

Before the cases are tied on, the upper part of all their ends except
the last should be cut shelving, that the fire from one may play over
the other, without being obstructed by the case. Wheel cases have
no clay driven in their ends, nor are they pinched, but always left
open; only the last, or those which are not to lead fire, which must
be well secured.

_Sec. IV. Of Water Mines._

A bowl and wheel, as above described, are necessary for this
exhibition; but with this difference that in the wheel there must be
a hole large enough to receive the mine. These mines are tin pots,
with strong bottoms, and a little more than two diameters in length.
The mine must be fixed in the hole in the wheel, with its bottom
resting on the bowl; then loaded with serpents, crackers, stars,
small water rockets, &c. in the same manner as pots of aigrettes; but
in the centre fix a case of Chinese fire, or a small gerbe, which
must be lighted at the beginning of the last case on the wheel. These
wheels are to be clothed as usual.

_Sec. V. Of Fire Globes for the Water._

Bowls for water globes must be very large, and the wheels on them of
a decagon form. On each side of the wheels, nail a piece of wood four
inches long; and on the outside of each, cut a groove, wide enough
to receive about one-fourth of the thickness of a four-ounce case.
These pieces of wood must be nailed in the middle of each face of the
wheel, and fixed in an oblique direction; so that the fire from the
cases may incline upwards. The wheel being thus prepared, tie in each
groove a four-ounce case, filled with a gray charge. Then carry a
leader from the tail of one case to the mouth of another.

Globes for these cases are made of two tin hoops, with thin edges
outwards, fixed one within the other, at right angles. The diameter
of these hoops must be somewhat less than that of the wheel. Having
made a globe, drive in the centre of the wheel, an iron spindle,
which must stand perpendicular, and be in length four or six inches
more than the diameter of the globe.

The spindle serves as an axis, on which the globe is fixed, which,
when done, must stand four or six inches from the wheel. Round, on
one side of each hoop, must be soldered small bits of tin, two and a
half inches distant from each other. These pieces must be two inches
in length each, and only fastened at one end, the other ends being
left loose, on which to turn round the small port-fires, to hold
them on: These port-fires must be made of such a length, as will
last out the cases on the wheel. There need not be any port-fires
at the bottom of the globe, within four inches of the spindle; for,
if there were, they would have no effect, but only burn the wheel.
All the port-fire must be placed perpendicular from the centre of
the globe, with their mouths outwards; and must all be clothed with
leaders, so as all to take fire with the second case of the wheel;
which cases must burn two at a time opposite to each other. When two
cases of a wheel begin together, two will end together; therefore
the two opposite end cases must have their ends pinched, and secured
from fire. The method of firing such wheels is, by carrying a leader
from the mouth of one of the first cases to that of the other; which
leader, being burnt through the middle, will give fire to both at the
same time.

_Sec. VI. Of Odoriferous Water Balloons._

Odoriferous works are generally fixed in rooms, and, when speaking
of scented fire, we noticed such compositions as would communicate
an agreeable odour to the air. Water balloons are made in the same
manner as air balloons, but very thin of paper, and in diameter 1-3/4
inches, with a vent, 1/2 an inch in diameter. The shells being made,
and quite dry, are filled with odoriferous composition, which must be
rammed in tight. These balloons are fired at the vent, and put into a
bowl of water.

Water rockets may also be made of any of the following compositions,
with a little alteration to make them weaker or stronger.

1. Saltpetre, 2 oz.
Sulphur, --
Camphor, ½ --
Yellow Amber, ½ --
Charcoal dust, ¾ --
Flowers of benzoin, ¼ --

2. Saltpetre, 2 oz.
Sulphur, ½ --
Antimony, ½ --
Amber, ½ --
Cedar-raspings, ¼ --
Oil of roses, 10 drops.
Oil of bergamot, 40 drops.

3. Saltpetre, 12 oz.
Meal-powder, 3 --
Frankincense, 1 --
Myrrh, ½ --
Camphor, ½ --
Charcoal, 3 --
Oil of Spike, a small quantity.

4. Saltpetre, 4 oz.
Sulphur, 1 --
Sawdust of Juniper, ½ --
Sawdust of Cypress, 1 --
Camphor, ¼ --
Myrrh, ¼ --
Dried rosemary, ¼ --
Cortex elaterii, ½ --

_Sec. VII. Of Water Balloons._

Having made some thin paper shells, fill some with the composition
for water balloons, and some after this manner: Having made the vent
of the shells pretty large, fill them almost full with water-rockets,
marrons, squibs, &c. Then put in some blowing powder, sufficient to
burst the shells, and afterwards fix in the vent a water-rocket, long
enough to reach the bottom of the shell, and its neck to project
a little out of the vent. This rocket must be opened at the end,
to fire the powder in the shell, which will burst the shell, and
disperse the small rockets, &c. in the water. When the large rocket
is well secured in the vent of the shell, take a cork float with
a hole in its middle, which fits over the head of the rocket, and
fasten it to the shell. This float must be large enough to keep the
balloon above water.

_Composition for Water-Balloons._

1. Saltpetre, 4 lbs.
Sulphur, 2 --
Meal-powder, 2 --
Antimony, 4 oz.
Sawdust, 4 --
Glass-dust, 1¼ --

2. Saltpetre, 9 lbs.
Sulphur, 3 --
Meal-powder, 6 --
Rosin, 12 oz.
Antimony, 8 --

_The following composition is given for Water-Globes._

Grain, or Corn-powder, 1 lb.
Saltpetre, 32 --
Sulphur, 8 --
Scraped ivory, 1 oz.
Sawdust (previously soaked in saltpetre and dried) 8 lbs.

_Sec. VIII. Of Water Squibs._

These are generally made of one-ounce serpent cases, seven or eight
inches long filled two-thirds with charge, and the remainder bounced.
The common method of firing them is this: Take a water-wheel, with
a tin mortar in its centre, which load with squibs after the usual
method; but the powder in the mortar must be no more than will throw
the squibs out easily into the water. The cases may be placed on the
wheel, either obliquely or horizontally, and on the top of the wheel,
round the mortar, fix two cases of brilliant fire perpendicularly to
the wheel. These cases must be fired at the beginning of the last
case of the wheel, and the mortar at the conclusion of the same.

_Sec. IX. Of the Water Fire-Fountain._

A float made of wood, three feet in diameter is to be provided. In
the middle, a perpendicular post, four feet high and two inches
wide must be inserted. Three circular wheels, made of thin wood,
but without spokes, are fixed round this post. The largest of these
wheels must be placed within two or three inches of the float, and
must be nearly of the same diameter. The second must be 2 feet 2
inches in diameter, and fixed at the distance of two feet from the
first. The third wheel must be 1 foot 4 inches in diameter, and fixed
within six inches of the top of the post.

The wheels being arranged, take 18 four or eight-ounce cases of
brilliant fire, and place them round the first wheel, with their
mouths outwards, and inclining downwards. On the second wheel, place
thirteen cases of the same, and in the same manner as those on the
first. On the third, place eight more of these cases, in the same
manner as before, and on the top of the post, fix a gerbe. Then
clothe all the cases with leaders, so that they and the gerbe may
take fire at the same time. The float should be tried first in the
water, to see if the fountain stands upright.

_Sec. X. Of Swans and Ducks, to discharge Rockets in Water._

This experiment may be made, by forming swans, or ducks of
paper, leaving a cavity within. They are to be filled with small
water-rockets, with some blowing powder to throw them out. Having
made and painted some swans, fix them on floats. Then in the place
where their eyes should be, bore holes two inches deep, inclining
downwards, and wide enough to receive a small port-fire. The
port-fire case for this purpose must be made of brass, two inches
long, and filled with a slow bright charge. In the middle of one
of these cases, make a little hole. Then put the port-fire in the
eye-hole of the swan, leaving about half an inch to project out, and
in the other eye, put another port-fire, with a hole made in it.
Then, in the neck of the swan, within two inches of one of its eyes,
bore a hole slantwise, to meet that in the port-fire. In this hole,
put a leader, and carry it to a water-rocket, that must be fixed upon
its tail, with its mouth upwards. On the top of the head, place 2
one-ounce cases, four inches long each, driven with brilliant fire.
One of these cases must incline forwards, and the other backwards.
They must be lighted at the same time as the water-rocket; to do
which, bore a hole between them in the top of the swan's head, down
to the hole in the port fire, to which carry a leader. If the swan is
filled with rockets, they must be fired by a pipe from the end of the
water-rocket, under the tail. When the swan is put in the water, the
two eyes are to be lighted.

_Sec. XI. Of Discharging Rockets under Water._

Stands must be made as usual, only the rails must be placed flat
instead of edgewise, and have holes in them for the rocket sticks to
go through; for if they were hung upon hooks, the motion of the water
would throw them off. The stands being made, if the pond is deep
enough, sink them at the sides so deep, that, when the rockets are
in, their heads may just appear above the surface of the water. To
the mouth of each rocket fix a leader, which must be put through the
hole with the stick. Then a little above the water must be a board,
supported by the stand, and placed along one side of the rockets; and
the ends of the leaders are to be turned up through holes made in
this board, exactly opposite the rockets. By this means, they may be
fired singly, or at once. Rockets may be fired by this method in the
middle of a pond, by a Neptune, a swan, or a water-wheel.

A rocket, which is fired in the water, and, after burning there half
the time of its duration, mounts into the air with great velocity,
may be thus constructed. Take a sky-rocket, furnished with a rod,
and, by means of a little glue, attach it to a water-rocket, but
only at the middle, in such a manner, that the latter will have
its neck uppermost. Adjust to their extremity, a small tube, to
communicate fire from the one to the other, and cover both with a
coating of wax, pitch, &c. that they may not be damaged by the water.
Then attach to the sky-rocket, after it has been thus cemented to the
aquatic rocket, a rod, and, by means of a string, support a musket
bullet, made fast to the rod by means of a needle or piece of iron.
When these arrangements have been made, set fire to the match after
the rocket is in the water, and, when the composition is in part
consumed, the fire will be communicated through the small tube to the
other rocket. The latter will then rise and leave the other, which
will not be able to follow it, on account of the weight adhering to
it.

_Sec. XII. Of the Representation of Neptune in his Chariot._

This representation is performed by procuring a figure made of wood,
or wicker wood, of the proper size, and supporting it on a float, on
which must be two horses' heads and necks, so as to appear swimming.
For the wheels of the chariot, there must be two vertical wheels of
black fire, and, on Neptune's head, a horizontal wheel of brilliant
fire, with all its cases to play upwards. When this wheel is made,
cover it with paper, or pasteboard, cut and painted like Neptune's
coronet; then let the trident be made without prongs; but, instead
of them, fix three cases of a very weak gray charge, and on each
horse's head, put an eight ounce case of brilliant fire, and on the
mouth of each, fix a short case of the same diameter, filled with the
white flame composition, sufficient to last out all the cases on the
wheels. These short cases must be open at bottom, that they may light
the brilliant fires. For the horses' eyes, put small port-fires, and,
in each nostril, put a small case, filled half with gray charge, and
the rest with port-fire composition.

If Neptune is to give fire to any building on the water; at his first
setting out, the wheels of the chariot and that on his head, with the
white flames on the horses' heads, and the port-fires in their eyes
and nostrils, must be all lighted at once. Then, from the bottom of
the white flames, carry a leader to the trident. As the figure is to
advance by the help of a block and cord, it must be so managed as to
prevent its turning about, till the brilliant fires on the horses and
the trident begin. For it is by the fire from the horses (which plays
almost upright,) that the building, or work is lighted, which must
be thus prepared. From the mouth of the case, which is to be first
fired, hang some loose quick-match, to receive the fire from the
horses. When Neptune is only to be shown by himself, without setting
fire to any other of the works; let the white flames on the horses be
very short, and not to last longer than one case of each wheel; and
let two cases of each wheel burn at a time.

_Sec. XIII. Of the Representation of a Sea-Fight with Small Ships,
and the Preparation of a Fire-Ship._

Having procured a number of small ships of two or three feet in
length, prepare a number of small reports, which are to serve for
guns. Of these, range as many as you please on each side of the upper
decks. Then, at the head and stern of each ship, fix a two-ounce
case, eight inches long, filled with slow port-fire composition; but
take care to place it in such a manner, that the fire may fall in
the water, and not burn the rigging. In these cases, bore holes, at
unequal distances from one another; but make as many in each case
as half the number of reports; so that one case may fire the guns
on one side, and the other, those on the opposite. The method of
firing the guns is by carrying a leader from the holes in the cases
to the reports on the decks. These leaders must be made small, and
care must also be taken in calculating the burning of the slow-fire
in the regulating cases, that more than two guns be fired at a time.
To give a broadside, let the leader be carried to a cracker, placed
on the outside of the ship; which cracker must be tied loose, or the
reports will be too slow. In all the ships, put artificial guns at
the port-holes.

Having filled, and bored holes in, two port-fires for regulating the
guns in one ship, make all the rest exactly the same. Then, when the
engagement has commenced, light one ship first, and set it a sailing;
and so on with the rest, sending them out singly, which will make
them fire regularly, at different times, without confusion; for the
time between the firing of each gun will be equal to that of lighting
the slow-fires.

The fire-ship may be of any size. To prepare a ship for this purpose,
make a port-fire, equal in size to those in the other ships, and
place it at the stern. In any port, place a large port-fire, filled
with very strong composition, and painted in imitation of a gun, and
let them all be fired at once by a leader from the slow fire, within
two or three diameters of its bottom. All along both sides, on the
top of the upper deck, lay star-composition, about half an inch thick
and one broad, which must be wetted with thin size, then primed with
meal-powder, and secured from fire by pasting paper over it. In the
place, where this composition is laid, some little tacks, with flat
heads, are to be driven, to secure it fast to the deck. This must
be fired just after the _sham_ guns, and, when burning, will show a
flame all round the ship. At the head, take up the decks, and put in
a tin mortar, loaded with crackers, which mortar must be fired by a
pipe from the end of the slow fire. The firing of the mortar will
sink the ship, and make a pretty conclusion.

Having prepared all the ships for fighting, we shall next proceed
with the management of them when on the water.

At one end of the pond, under the surface of the water, fix two
running blocks, at the distance the ships are to fight apart, and at
the other end of the pond, opposite to each of these blocks, under
water, fix a double block. On the land, by each of the double blocks,
place two small windlasses. Round one of them, turn one end of a
small cord, the other end of which is to be put through one of the
blocks. Then carry it through the single one at the opposite end of
the pond, and bring it back through the double block again, and round
the other windlass. To this cord, near the double block, tie as many
small strings, as half the number of ships, at the distance required.
These strings, however, should not be more than two feet each. Make
fast the loose end of each to a ship, just under the bowsprit, but if
tied to the keel, or too near the water, it will overset the ship.
Half the ships being thus prepared, near the other double block,
fix two more windlasses, to which fasten a cord, and to it, tie the
other half of the ships as above. When the ships are fired, turn that
windlass which draws them out, and so on with the rest, till they
are all out in the middle of the pond. Then by turning the other
windlass, they will be drawn back again; by which method, they may
be made to change sides, and tack about backwards and forwards at
pleasure.

For the fire-ship, fix the blocks and windlass between the others; so
that, when she sails out, she will be between the other ships. She
must not advance, however, till the guns at her ports take fire.

In the exhibition of water fire-works, it is obvious, from the
observations we have made, and the different pieces prepared for that
purpose, that such exhibitions may be varied, and even new pieces got
up.

CHAPTER XII.

OF THE ARRANGEMENT OF FIRE-WORKS FOR EXHIBITION.

Jones (_Fire-works_, 8vo. 1776) observes, among other remarks, that
nothing adds more to the appearance of fire-works, than placing
them properly; though the management of them chiefly depends on the
judgment of the maker. When water-works are to be exhibited, divide
them into several sets, and fire one set after every fifth or sixth
change of land and air works. Observe this rule in firing a double
set of works; always to begin with sky-rockets; then two moveable
pieces; then two fixed pieces, and so on; ending with a large flight
of rockets, or a marron battery. If a single collection, fire a fixed
piece after every wheel or two, and occasionally some air and water
works.

The rules, adopted in the arrangement of fire-works for exhibition,
are the following: If they are a double set, place one wheel of a
sort on each side of the building; and, next to each of them, towards
the centre, place a fixed piece; then wheels and so on, leaving a
sufficient distance between them, for the fire to play from one,
without burning the other. Having fixed some of the works in front,
place the rest behind them, in the centre of the intervals. The
largest piece, which is generally a regulated or transparent piece,
must be placed in the centre of the building; and behind it a sun,
which must always stand above all the other works. A little before
the building, or stands, place the large gerbes; and, at the back of
the works, fix your marron batteries, pots des aigrettes, pots des
bins, pots des saucissons, air balloons, and flights of rockets. The
rocket-stands may be fixed behind, or any where else, so as not to be
in the way of the works.

Single collections are fired on stands, which stands are made in the
same manner as theodolite stands; only the top part must be long
or short, according to circumstances. These stands may be fixed up
without much trouble. The following is the order of firing works,
_viz_:

1. Two signal }
2. Sky }
3. Two honorary } Rockets.
4. Four caduceus }
5. } { Vertical }
6. } Two { Spiral } Wheels, illuminated.
7. } { Transparent stars.
8. A line of rockets of five changes.
9. Four tourbillons.
10. } { Horizontal wheels.
11. } { Air-balloons, illuminated.
12. } Two { Chinese fountains.
13. } { Regulating pieces, of four mutations each.
14. } { Pots des aigrettes.
15. Three large gerbes.
16. A flight of rockets.
17. } { Balloon wheels.
18. } Two { Cascades of brilliant fire.
19. Twelve sky-rockets.
20. } { Illuminated yew trees.
21. } Two { Air balloons of serpents, and two compound.
22. Four tourbillons.
23. } { Fruiloni wheels.
24. } Two { Illuminated globes with horizontal wheels.
25. One pot des saucissons.
26. Two plural wheels.
27. Marron battery.
28. Two chandeliers, illuminated.
29. Range of Pots des brins.
30. Twelve sky-rockets.
31. Two yew-trees of fire.
32. Nests of serpents.
33. Two double cones, illuminated.
34. Regulating piece of seven mutations, viz.
1. Vertical wheel, illuminated.
2. Golden glory.
3. Octagon vertical wheel.
4. Porcupine's quills.
5. Cross fires.
6. Star piece with brilliant rays.
7. Six vertical wheels.
35. Brilliant sun.
36. Large flight of rockets.

According to the arrangement, and execution of fire-works for
exhibition, as given by Morel (_Traité Practique des Feux
d'Artifice_, p. 131,) the following order is observed:

1. A salvo of artillery.
2. Six dozen rockets of honour, discharged two at a time
from each side of the decoration.
3. Twelve Bengal lights, distributed in such a manner, as
to light all parts of the decoration.
4. Two batteries of ordnance, (fire-pots.)
5. Four regulated cases, each consisting of two dozen rockets
of an inch caliber, forming the _mosaique_ at the elevation
of five hundred feet.
6. Eight turning suns, with the caliber of five-sixths of an
inch.
7. Four caprices (detonating.)
8. Two balloons of golden rain, and two in stars.
9. The pyric piece, complete.
10. Twelve tourbillons, or table rockets.
11. Four girandoles; two mosaic, and two of Roman candles.
12. A large sphere.
13. Six balloons; three in golden rain, and three in stars.
14. Twenty-four honorary rockets, fired four at a time.
15. A large illuminating cut-work, with a device, accompanied
with two Chinese parasols, and two wheels of coloured
fire.
16. Four falling caprices.
17. Twelve balloons of stars, preceded by six dozen honorary
rockets, fired twelve at a time.
18. The undulating fire, accompanied with eight _wings_,
four on each side.
19. A battery of two hundred mosaics, and as many Roman
candles, with marrons and fire-pots.
20. Illumination of the decoration, with four mosaic tourbillons,
followed by two cases, containing two hundred
rockets each; and a salvo of artillery, which announces
the departure of the _girande_, composed of a thousand
rockets, in golden rain.

PART IV.

MILITARY PYROTECHNY.

CHAPTER I.

OBSERVATIONS IN GENERAL.

Laboratory-works comprehend all the operations of the _workshop_,
connected with this branch of pyrotechny. The tools and instruments
required for the laboratory, as well as the substances employed in
the different preparations, we have already described.

Having noticed the origin of gunpowder, in the first part of our
work, the following remarks in relation to that subject, namely, the
history, of cannon, may be interesting.

For some time after the invention of artillery, gunpowder was of a
weaker composition than that at present used, or than that described
by Marcus Græcus. The first pieces of artillery were rough and very
inconvenient, being usually framed of several pieces of iron bars,
fitted together lengthwise, and hooped with rings. These guns were
first employed in throwing stone shot of a prodigious weight, in
imitation of the ancient machines, to which they succeeded, and were
of an enormous bore. When Constantinople was besieged by Mahomet II.
in the year 1453, the walls were battered with stone bullets, and
some of the pieces were of 1200 lbs. caliber; but they could not be
fired more than four times in twenty-four hours, and sometimes were
burst by the first charge.

As mathematical knowledge increased in Europe, that of mechanics
gradually advanced, and enabled artists, by making brass cannon of
a much smaller bore for iron bullets, and capable of bearing a much
greater charge of strong powder in proportion to their calibers, to
produce a very material and important change in the construction
and fabric of those original pieces. Guicciardin (_History_, &c.
_1st book_) informs us, that, about 114 years after the first use
made of those unwieldy pieces by the Venetians, in their war
against the Genoese in 1380, the French were able to procure, for
the invasion of Italy, a great number of brass cannon, mounted on
carriages, drawn by horses. He then enumerates the advantages which
these pieces possessed, and particularly that they could be pointed
with incredible quickness and expedition, in comparison with those
formerly made use of in Italy. But, as our limits will not permit
us to notice all the circumstances in connection with these pieces,
it is sufficient to remark, that this change in the formation of
artillery has as yet undergone no material alteration; if we except
the introduction of carronades, first suggested by general Melville,
and of Columbiads, by the late Mr. Barlow.

Glenie (_History of Gunnery_, 1776) appears to have been the first,
who gave the theory of projectiles in vacuo by plain geometry,
or by means of the square and rhombus, with a method of reducing
projections on inclined planes, whether elevated or depressed below
the horizontal plane, to those which are made on the horizon. The
experiments, and observations, of Mr. Robins, on the subject of
gunpowder, &c. may be seen in the article on gunpowder.

Besides the formation of cannon, by uniting iron bars together,
and strengthening them by hoops, (one or two of which were made in
Philadelphia in 1776, by a Mr. Wheeler, of a superior kind,) others
were made of thin sheets of iron, rolled up together and hooped; and
on emergencies, they were made of leather, with plates of iron or
copper. Stone balls were used, and a small quantity of powder. In the
13th century, cannon were used in a sea fight, between the king of
Tunis and the Moorish king of Seville. The Venetians used cannon at
the siege of Claudia Jessa, now called Chioggia, in 1366, which were
brought thither by two Germans, with some powder and leaden balls;
as likewise in their wars with the Genoese in 1379. At the battle
of Cressy, in 1346, Edward III made use of cannon. They were also
employed in the seige of Calais, in 1347. Pieces of ordnance were
made use of by the Turks, at the siege of Constantinople, then in
possession of the Christians, in 1394, or in that of 1452, that threw
a weight of 1006 lbs. Louis XII had one cast at Tours, of the same
size. One of those cannon was taken at the seige of Dieu, in 1546, by
Don John de Castra, and is in the castle of St. Juliao de Barra, 10
miles from Lisbon. Its length is 20 feet 7 inches, diameter at the
centre, 6 feet 3 inches, and it discharges a ball of 1000 lbs. It has
neither dolphins, rings, nor buttons, is of a curious kind of metal,
and has a large Indostan inscription upon it, by which it appears it
was cast in 1400. The mortars at the Dardanelles are represented to
throw shells, or ball of an immense size and weight.

Some do not consider cannon an European invention; because it is
asserted, that authentic documents exist of their use in China, many
centuries before they were thought of in Europe. If they say, the
testimony of the Chinese themselves is not sufficient on this point,
the fact of their great wall being furnished with embrasures, fitted
in such a manner for cannon, leaves no doubt of their having been in
use at the time of its erection. To this, an additional argument may
be added, from their very ancient game of chess, in which pieces have
been used from remote antiquity, designating engines of war, whose
power was derived from gunpowder. Mr. Irvin, (_Trans. Royal Irish
Academy_,) in his paper on the Chinese Game of Chess, proves, that
gunpowder was in common use in China, 371 years after Confucius, or
161 years before Christ; and Du Halde has long since given documents
to show, that the Chinese wall was in existence 200 years before the
commencement of the Christian era; and consequently, for the reason
before stated, the use of cannon must have been of at least equal
antiquity. The Asiatic Researches contain some remarks to the same
point. There is a strong probability then, that the invention of
guns was of a much more remote date. It is not impossible, however,
that the same thing may have been invented by different persons, in
various parts of the world.

We mentioned, that it is much more probable, that the use of
gunpowder in war was derived ultimately from the Chinese,
notwithstanding the generally received opinion, that the Greek fire
was the progenitor of its discovery; or that Bacon, or Schwartz, an
obscure monk, has claims to the invention. The mode in which the
use of gunpowder in war might have passed from China to Europe, is
the most probable and simple imaginable. Zingis Khan is known to
have conquered the five northern provinces of China, about the year
1234. He must have known the common use of gunpowder at that period,
as it had been known in China 1400 years before. In the _Chinese
annals_ of the Moguls, by Yuen, as translated by Pére Gaubil, it is
particularly stated, that the use of cannon and mortars was familiar
in the wars and sieges of Zingis against the Chinese, both by them
and him, in attack and defence. It is most probable, that he used
gunpowder in his wars against Mahomet, Sultan of Carisme, whose
dominions extended from the Persian Gulf, to the borders of India and
of Turkistan. It is known, that he had a body of Chinese engineers in
his army, who, of course, must have been acquainted with the use of
gunpowder.

The conquests of Zingis would thus have spread the knowledge of
gunpowder, &c. over the western part of Asia; and the Europeans,
in their crusades, may have had frequent opportunities of becoming
acquainted with it. It was just after this time, that it became
known, and was used in the European wars.

Sir Francis Bacon (_Moral and Political Essays_,) observes, that
"ordnance was known in the city of Oxydraces, in India, and was that
which the Macedonians called 'thunder, lightning, and magic;' and
it is well known, that the use of ordnance had been common in China
above two thousand years."

Beckman, (_History of Inventions_, iii, p. 434,) in his essay on the
origin of guns and gun-locks, has given, at some length, the history
of guns. All we can add here, is, that the first portable fire-arms
were discharged by means of a match, which, in the course of time,
was fastened to a cock, and afterwards a fire stone and steel plate
were used. This fire stone was not a flint, but a compact pyrites, or
marcasite, (sulphuret of iron), which was distinguished by that name.
On each new improvement, the piece received a new name; as, _büchse_,
_haken büchse_, _arquebuse_, &c. After explaining the origin of these
names, he adds, that the large pieces were conveyed on carriages,
called _karrenbüchse_, but soon after also _canna_, cannon. Pistols
are mentioned by Beilay, in 1544, in the time of Francis I; and
under Henry II, the German horsemen were called _pistoliers_. The
name is derived from Pistoia, in Tuscany; because they were there
first made. Muskets received their name from the Latin _muschetus_,
which signifies a male sparrow-hawk. They were first used at the
seige of Rhege, in the year 1521. They were known in France in the
time of Francis I. Brantome, however, asserts, that they were first
introduced by the Duke of Alva, in 1567, and used in the Netherlands.
He also says, that they were made general in France by M. de Strozzi,
under Charles XI. The lock was invented in Germany, in the city of
Nuremberg, in 1517; it is uncertain whether it is the present lock.
In the arsenal at Hanover, there are many ancient pieces. The oldest
had on the barrel, the figure of a hen with a musket in its mouth;
because it is said they were made at Henneberg.

There are three species of cannon, the _gun_, the _howitzer_, and the
_mortar_. The gun is the longest piece of artillery, employed at the
present day: the _culverins_, _dragons_, &c. as they were formerly
called, had calibers twice, and even three times as long as those now
used. Guns were originally called _bombards_, and were eight calibers
in length. The term _pieriers_, from _pierre_, a stone, were given
to some guns, because they were employed in throwing rough stones.
The carronades, derived from the river Carron, in Scotland, where
they were originally made, is a short gun, with a bore about eight
diameters of the shot in length. The howitzer is a species of mortar,
but longer, and used to throw a hollow projectile, called a howitz,
which acts at first as a _ricochet_ ball. The mortar is the shortest
species of cannon, and is used to throw bombs or shells. A stone
mortar is used in sieges, to throw stones upon an enemy. Besides
these descriptions of guns, there is another division, to which
General Lallemand (_Treatise on Artillery_, vol. 1, p. 20,) has given
the name of _demi-guns_, under which he ranks the _harquebus_ on a
swivel, the _rampart gun_, and the _repeating gun_, or _musket_, of
the Americans.

He observes, that the harquebus nearly resembles the _amusette_
of Marshal Saxe, has a barrel like that of a musket, and carries
a ball weighing half a pound or more; that the rampart gun, or
wall piece, is a large musket, that was anciently much used in the
defence of fortresses, having a barrel of 5-1/2 or 6 feet long, and
a ball from 10 to 14 to the pound; and that the repeating musket is
a gun, consisting of 7 barrels, all of which discharges 32 rounds
in succession, making 224 in all. With respect to this gun, the
effect of which we have witnessed, not only in the discharge of
thirty-two rounds from a single gun, but the combined effect of
seven or more barrels, the General observes, that the diameter of
the bore is three-fourths of an inch, and the weight seventy pounds.
It is placed, like the rampart guns, upon a wooden frame, and has a
handle at the breech to point by. As to its use, he adds:--it may be
advantageously employed in the defence of places at the moment of
assault; it may be useful in the field, to defend parts of a line of
battle, or entrenchments, with few troops, and yet astonish the enemy
by a warm fire, when he ventures to approach. Its discharge does not
last a minute. It may be of great service in the tops of ships of
war.

The inventor is a Mr. Chambers, of Pennsylvania. We witnessed its
effect, when the President of the United States visited the navy yard
in Philadelphia, where the inventor manufactured them; and also at
Bush-hill, in the neighbourhood of that city. Having examined their
construction, and also the shot it may be sufficient to remark, that
the lead is cylindrical, one end being flat, and the other conical,
and of such a size as to fit the caliber of the musket; that these
rounds are pierced with a hole in the centre, which is charged
with fuse composition; and, after a charge of powder, one of these
cylinders is put in; then a charge, then a cylinder, &c. up to 32.
The lock is placed opposite the last charge, so that when the first
load is discharged, the fire communicates successively _through the
cylinders_.

A repeating gun has been invented by a gentleman of New York. I have
seen no description of it. The Marquis of Worcester, in his Century
of Inventions, in the 58th to the 64th invention, hints at a similar
contrivance; as for instance, (Inven. 58th,) "How to make a pistol
to discharge a dozen times with one loading, and without so much as
one new priming requisite, or to change it out of one hand into the
other, or stop one's horse."

We may add, that, in 1764, M. Bouillet and Sons presented, to the
Academy of Sciences, at Paris, a musket of their invention, which
was lighter than the common kind, and had the property of firing
twenty-four times in succession, charging and priming itself by a
single circular movement of the musket upon an axis, fixed for that
purpose. In the file of the _French Gazette_, for 1786, article
Linberg, there is an account of an invention of the baron De
Walskohl. It is the same, it would appear from the description, as
the repeating musket. Being once charged, it will fire thirty-six
times in succession. The experiments made with it were satisfactory.

Many patents have been secured in this country, and in England and
France, for improvements on the musket and rifle; but, in order to
accommodate short-sighted persons, M. Regnier's invention appears to
be the first which consists in an _optic_ glass fixed in the butt,
enabling persons of that description to shoot with accuracy. This
invention is given in the _Journal de la Blancherie_ for 1779, p. 194.

In 1771, Moret, an armourer, announced a new constructed pistol,
which would charge itself, &c. and in 1793, M. Gass presented to
the military committee of France, a pistol of a new construction,
calculated to fire several _ball_ in succession. The _Journal des
Inventions et Découv._ i, p. 121, speaking of this invention, adds,
that the means employed depended entirely on the construction of the
ball, which, instead of round, was a cylinder, pierced in its length.
This small canal is filled with meal-powder, and serves as the match
of communication to the charges. This contrivance is much the same as
the one we have described.[29]

Mr. Misson (_Travels through Germany and Italy_,) says, that in the
arsenal at Venice, there is an engine which will light five hundred
matches at once, and some very curious arms of ancient make, among
which is a small trunk, with six little guns, which Carrara, the last
lord of Padua, who was famous for his inhumanity, sent as a present
to a lady; and was so contrived, that, upon opening of the trunk, the
guns all fired at once, and killed her!

With respect to the invention of the various incendiary machines,
we may observe generally, (as we purpose to notice them in their
respective places), that Greek fire was employed in different ways,
and was considered a destructive composition; that rain-fire, bombs,
lances, matches, fire-balls and carcasses, torches, powder sacks,
petards, &c. were all employed in more modern times for the same
purpose; and, lastly, that the _fougette_ of the Asiatics, called
Indian rockets, the Congreve rocket, the incendiary bomb of the
French, and the floating rocket carcass, are embraced under the same
head, and are all used for similar purposes in war. These, and other
subjects, belonging to military fire-works, we purpose to mention in
this, and the following chapters.

_Sec. I. Of Cartridges._

Cartridges are cases of paper, parchment, or flannel, fitted to the
caliber of the piece, and holding exactly its proper charge. Strong
paper is always used for musket and pistol cartridges, and the French
musket-ball-cartridges are capped with flannel or coarse cotton. For
heavy guns, they are made of thick, and as the English call it, of
_cured_ paper, with flannel bottoms. Those for field ordnance are all
made of flannel, and their size suited to the bore, or chamber of
pieces, for which they are intended. The ball cartridges, for wall
pieces, muskets, carbines, and pistols, are made of whitish-brown
paper, on formers of wood. A sheet of paper will make six for wall
pieces, twelve for muskets, sixteen for carbines, and twenty-four for
pistols. The quantity of powder they contain respectively is, for
wall pieces ten drachms, musket six, carbine four, and pistol three
drachms.

Blank cartridges, for pistols, carbines, and muskets, are made of
blue paper, to preserve a distinction between ball and blank, and to
prevent the possibility of accidents, from the ball cartridges being
mixed with the blank.

The charge for muskets is commonly half the weight of the ball.
The balls for musketry are eighteen to the pound; and one pound of
powder is sufficient for thirty-six cartridges.[30] Forty cartridges
may be used to the pound, but forty-five would be too weak. The
paper, necessary to form cartridges, should be well sized and not too
thick. It is made for the purpose, under the name of cartridge paper,
and should be of such a size as to cut to advantage. It is usually
fourteen inches in length, and sixteen in breadth. A sheet will form
twelve cartridges, but on account of wastage, it makes only ten.
Half a sheet is employed as a wrapper for every ten cartridges, and
one and a half sheets are used for ten and their wrapper. Six quires
will make 1000 cartridges, and 31 reams, 100,000. Five ounces of
packthread are necessary for binding 1000 cartridges, and 31 lbs. for
100,000.

Musket cartridges are made in the following manner. Long tables are
provided, and, at certain distances, excavations, or holes are made,
larger than the diameter of the ball, and one-third of its diameter
in depth. These holes are designed for rounding the folds upon the
ball. It is necessary first to be provided with formers to roll the
cartridges upon, and measures to fill them with. These formers are
made of hard and dry wood, seven inches, or seven and a half inches
in length, and six-tenths of an inch in diameter, one-twelfth of an
inch less than the diameter of the caliber. One end is rounded so
as not to hurt the hand; the other is hollow, to receive one-third
of the ball. The measures are in the form of the frustrum of a
cone, open above. They are made of sheet-tin, and should contain
one-fortieth part of a pound of powder, (one-forty-ninth according to
the Strasburgh directions), or, when heaped, one thirty-sixth part
of a pound. The height of these measures is one inch and a quarter;
their diameter at the large end one inch and one-twelfth, and at the
smaller end, three-quarters of an inch. In every squad of ten men,
six are employed to roll the cartridges, two to fill them, and two to
pack them. Each squad may make 10,000, but commonly 8,000, in a day.

To cut the paper for musket cartridges, we begin by folding the
sheet in three parts widthwise; then each third part into two, again
into three, and again into two, by a diagonal line which takes from
2.2 inches of a superior angle on the left, to 2.2 of the opposite
inferior angle at the right; so that every sheet of paper will cut,
without loss, into twelve parts, and every part will be 5.68 inches
in height, 4.53 in width at one end, and 2.2 at the other end.
According to Bigot, however, each trapezoid thus formed is 5-1/3
inches in length, 4-1/4 in width at one end, and 2-1/4 at the other
end. The paper is cut by a person detailed for the purpose.

The person who rolls the cartridges, having spread the cut paper upon
a table, takes the form with one hand, and the ball in the other,
which he puts into the hollow of the form; after which, he rolls the
paper round the ball and the form, so that there remains sufficient
beyond the ball, to fold over in small folds; then he rolls the
form surrounded with the paper, and having rounded the folds upon
the ball, in a small hole made for that purpose in the table, he
withdraws the form, and passes the cartridge to the man who is to
fill it. He puts in the charge with a small tin measure, folds the
paper over upon the powder as close as possible, and passes it on to
him who is to make the packages. The packer takes ten in his hand,
and arranges them on a sheet of paper folded in two, the balls half
on one side and half on the other; and having wrapped them in the
paper, he folds over the two ends, and ties the packets crosswise
over the middle, and lengthwise.

Musket cartridges cannot be too tightly rolled upon the form; and
to ascertain their accuracy, they must be calibered before they are
loaded; that is, they must be put into the end of a musket. He who
fills them, should make a charge complete in every cartridge, and not
load one more than another, but always pour a full measure into every
one. The packer should tie the cartridges, and round them as much as
possible, without tearing the paper. He should take care that all the
packets are of the same length; so that they may be placed in the
partitions of the ammunition chest, which are all of one determined
length, and will not therefore contain them, if made too long.

Cannon cartouches should be well arranged in the ammunition chests,
and well stowed with tow, that they may be carried without danger of
injury from the road. The tow is pressed down in small quantities, by
a little wooden spatula, and cannot be pressed too hard; for the more
the chests are stuffed with tow, the better the ammunition will be
preserved.

Musket cartridges are placed in the ammunition chests in different
arrangements, the height of which is proportioned to that of the
cartridge. There are three stories in height in each chest, for
musket cartridges; and between each a small separation, to prevent
them from injuring each other. The number of cartridges contained
in an ammunition wagon is proportioned to the kind of wagon in
use, and to the quantity necessary for the service. The common
load of ammunition wagons does not exceed thirteen hundred weight,
if it is meant to take the benefit of forced marches. In every
ammunition wagon for cannon cartouches, there are cartouches with
ball, grape-shot, quick-match, and port-fires, staffs for port-fires,
priming wires and match-rope--so that every wagon contains all kinds
of ammunition relative to its caliber. In an ammunition wagon filled
with musket cartridges, a certain number of flints are contained, to
be distributed to the troops from the same chest whence they receive
their ammunition.

We might here speak of the load of every ammunition wagon; but this
subject more particularly belongs to artillery and its suite, than to
fire-works.

Cartridges, used in sieges, &c. are made of paper bags, of the
calibers of the different pieces, and of a sufficient length to
contain the requisite quantity of powder. The paper should be large
and strong.

The handle of each of the formers should have such a length and size,
as to render them convenient to hold in the hand. Care must be taken
to pierce a small hole in the middle, through the whole length of the
form, by which the air might enter to the cartouches, and cause the
form to be more easily drawn out, after the cartridge is made.

Pasted cartridges are formed in the usual manner upon a former; and
when five-sixths of the paper are rolled, the remaining portion is
pasted with a paste made of flour and glue, mixed together. The
bottom is pasted over in the same manner. When the cartridge is drawn
off the former, it is placed to dry in the sun, or near a stove.

With regard to the cost of cartridges in France, it appears, that
a pound of packthread costs twelve sous, and workmen receive from
fifteen to twenty sous per thousand for their labour. The whole
expense of 100,000 would be, for paper, 105 livres; for packthread,
18 livres, 15 sous; for making 100 livres; total 223 livres, 15 sous.
Bigot has furnished us with the following estimate:

For 31 reams of paper, at 4 fr. 50 c. the ream, is 140 fr. 60 c.
For 31¼ lbs. of packthread at 80 centimes, 24
Labour, 1 fr. per thousand, 100
Five days work, for the cutter, 5
-------------
Total. 269 fr. 60 c.

One hundred thousand cartridges, for which the above is a
calculation, require also

Bullets of lead, 5556 lbs.
Powder, 2500 lbs.

_Sec. II. Of Cannon Cartridges._

The _gargousse_ of the French, in artillery, is a sack or bag of
paper, or parchment, destined to enclose the load of a cannon. When
it is made of serge, it is then called a pouch, (_sachet_); and, when
united with the ball, it receives the name of ball-cartridge.

Bigot remarks, that these cartridges have been substituted for the
dangerous and unsafe use of the spoon, or ladle, (_lanternes_,
Fr.[31]), by means of which the load was carried to the bottom of
the piece. They are paper bags or sacks, of the caliber of the gun.
The loading is much more expeditious, and less danger is to be
apprehended. It requires only, that the piece should be well sponged,
and the priming to communicate with the load.

For the construction of these cases, coarse gray paper, and
sufficiently strong, is used; and they should be well pasted.
The paper, which is used with advantage, and commonly employed,
is 23 inches in length, and 28 inches in breadth. It serves for
all calibers, and even proof charges, which are stronger than the
ordinary loads. The paper is cut of such a size as to leave from
1-1/4 inches, to 1-1/2 inches, on the roller, and a sufficiency to
cover the lower extremity. One of the sides, as well as the side
which is cut, is pasted. The paper is rolled upon the former, or
roller, and is straightened, so that the hand may be passed over the
pasted part, and the paper tightened. The bottom of the bag is placed
upon the roller, and, in folding it, the bag is tied above that part
of the paper, which is pasted. The bag is then dried, by placing it
on one end upon a table, and exposing it to the air.

The rollers should be bored in their axis, so that, in drawing them
out, they may come out easy, and without injuring the bag. This hole
admits the external air, and prevents the formation of a vacuum
in a degree, when the roller is suddenly withdrawn. The bottoms
(_culots_,) are cut of the same diameter as the roller. The paste is
made of flour and glue.

The table given by Bigot, p. 28, relative to the dimensions of sacks
or cartridges, for cannon, embraces the following particulars: The
diameter of the former, or roller for a 24 pr. is 5-1/6 inches: for
a 16, 4-1/2; for a 12, 4; for an 8, 3-1/2; for a 6, 3-1/6; and for a
four pounder 2-3/4 of an inch: the circumference of the cartridge for
a 24 pr. is 17-2/3 inches; for a 16, 15-3/12ths; for a 12, 13-1/3;
for an 8, 12-11/12; for a 6, 6-1/2; for a 4, 9-2/3ds inches. The
height of the roller for a 24 pr. is 18 inches; for a 16, 15; for a
12, 14; for an 8, 13; for a 6, 12-1/2, and for a 4, 12. The height
of the paper, including the circumference, for a 24 pr. is 17-2/3
inches; for a 16, 14; for a 12, 14; for an 8, 11; for a 6, 10-1/2;
for a 4, 10. The height, which covers the cartridge, is for a 24 pr.
1-5/10 inches; for a 16, 1-3/12; for a 12, 1-1/12; for an 8, 11/12;
for a 6, 10/12; and for a 4, 9/12. The bottom (_culot_,) for a 24 pr.
is 1-2/12th inches; for a 16, 1; for a 12, 10/12; for an 8, 2/3ds;
for a 6, 7/12; and for a 4, 1/2 inch. The height of the charge for a
24 pr. is 11-1/6 for a 16, 8-1/2; for a 12, 8-1/6; for an 8, 7-1/3;
for a 6, 6-9/11; and for a 4, 6-2/12ths inches. The height of the
paper, for the charges of exercise, is for a 24 pr. 10 inches; for
a 16, 9; for a 12, 8; for an 8, 7; for a 6, 6-1/2; and for a 4, 6
inches.

In the table of the proportions of the charge, for different
calibers, given by Ruggieri, (_Pyrotechnie Militaire_, p. 197,)
besides the weight of the ball, and the height of the sack, the
weight of the charge is given in pounds, and ounces, which is thus
stated by him: for a 4 pr. 1 lb. 8 oz; an 8 pr. 2 lbs. 8 oz; a 12 pr.
4 lbs. 8 oz; a 16 pr. 5 lbs; and a 24 pr. 8 lbs.

_Cannon Cartouches_ are composed of a bag of serge, and a shoe or
base, in which the ball was fixed by means of a tin cross, nailed to
the shoe or base. The bag should be as large as the shoe, and long
enough to contain the requisite quantity of powder. The shoe is a
little less in diameter than the ball, so that the tin and the bag
put upon it, do not increase its size beyond that of the ball. The
shoe is flat on one side, and hollow on the other. The hollow part
should be a spherical concavity, about one-third of the diameter of
the ball. At a small distance from the bottom of the shoe, a groove
is made sufficiently deep to contain the packthread, with which it is
fastened to the bag.

In the construction of cannon cartouches, the ball must first be
fixed to the base by means of two tin bands in the form of a cross,
and nailed with two small nails at the bottom and sides of the base.
These bands for sixteen and twelve pounders, are at least .44 decimal
parts of an inch in width, and 15 inches long. Those for eight and
four pounders, are .355 decimal parts of an inch in width, and 11.72
inches in length.

The ball being fixed on this base, it is put into a bag filled with
powder, and the bag tied above to the base. Then a bit of parchment
soaked in water, of from two to four inches in width, and of
sufficient length to go round the cartouch, is placed round the bag,
half on the shoe and half on the powder. Then tie it with a string
passing in the groove, at about .27 parts of an inch below the base;
so that the cartouch is tied in three different places--the two
first above in the groove of the shoe, serves to hold the bag and it
strongly together; the third below, is to prevent the powder from
rising and slipping between the bag and the shoe. The band is placed
on the part where the greatest friction is, to preserve the bag from
being torn.

The cartouch thus made, is to be calibered by trying it with the
piece for which it is intended, into which it must enter with ease.
This cannot be too strongly recommended. It is of all things the
most essential, and the only way of ascertaining the goodness of
ammunition.

A workshop of twelve workmen is divided into four classes. The first
class consists of two men who put the ball into the shoe; the second
of two others who fill the bag with powder; the third, two others who
press the powder into the bag; and the remaining six are employed in
tying the bags to the shoes, two to each.

These twelve workmen can, in one day of twelve hours, make two
hundred and forty cartouches, of sixteen or twelve pounders, or 320
of eight or four pounders.

_Table relative to the Cartouch, or Pouch._

------------------+---------+---------+---------+---------+------------
For | 12 | 8 | 6 | 4 |Light Troops
------------------+---------+---------+---------+---------+------------
Height, without | Inches. | Inches. | Inches. | Inches. | Inches.
the folds. | 11 | 10 | 9½ | 9 | 6
Circumference, | | | | |
without the folds.| 12-7/12 | 10-9/12 | 9¾ | 8½ | 5-3/12
Diameter of | | | | |
the base, without | | | | |
the folds. | 4 | 3-5/12 | 3-1/12 | 2-9/12 | 1-8/12
------------------+---------+---------+---------+---------+------------

To make _grape shot_, we must have a bag of ticking, in which the
small balls are arranged; also a shoe, to which not only the bag
which contains the ball is attached, but also the serge filled with
powder.

The shoe is made of the same wood with the ball cartridges, and of
the following dimensions, viz. The sixteen pounder should have 4.97
inches diameter; the twelve pounders, 4.35; the eight pounders, 3.82;
and the four pounders, 3.1 inches diameter. Those of the caliber of
sixteen and twelve, should be 1.6 inches in thickness, with a groove
in the middle of .44 parts of an inch in depth, and the same in
width; the eight and four pounders have but 1.07 inch in thickness,
with a groove in the middle of .36 parts of an inch in depth and
width. Every shoe or base, has a pin in its centre, the size of
which is in proportion to the vacancy left by the small balls of
iron arranged about it. The height is in proportion to the different
layers of ball.--In general thirty-six balls are put into one grape
shot, of whatever caliber it be; that is to say, six heights of six
each. The balls should be proportioned to the caliber, so that the
six balls on the base should exactly fill the circumference of it.
The pin in the middle of the base is exactly the size of the ball and
seven times its diameter in height. At the top of the pin a groove
is made to tie the threads, the width of which is one-third, and the
depth, one-fourth of its diameter.

The bag in which the small balls are arranged, layer upon layer,
should be of good strong ticking closely woven. It is of the size
of the shot, and 2.13 inches in length above the top of the pin. It
is strongly fastened at the bottom in the groove of the base with
strong pack-thread. There must be 3-1/2 fathom of strong pack-thread
trebled, to tie the grape of the caliber of sixteen and twelve
pounders, and three fathom only for one of eight and four.

Grape shot may be corded in the same manner as the carcase is corded;
with this difference, instead of eight turns, taking only six. The
best and strongest method of tying the thread in grape-shot, is in
the net-work form--one person holding, and another tying it.

In a work-shop where ten men are employed, eight are employed to wind
the thread round, and two to attach the bag to the base or shoe,
or to arrange the small balls on the shoe, round the pin. Such a
work-shop, in a day of ten hours, can complete 120 grape-shot of the
largest caliber, and as many as 140 of eight or four pounders might
be made.

The grape shot composed of 36 iron balls, weigh, without their charge
of powder, as follows:

lb. oz.
For a caliber of 16 21 10
For do. of 12 16 3⅕
For do. of 8 10 12⅘
For do. of 4 6 3⅓

The diameters of the small balls for grape shot, of which six exactly
fill the circumference, are as follows:

For 16 pounders, 1.66 inch. For 8 pounders, 1.31 inch.
For 12 do. 1.5 do. For 4 do. 0.16 do.

_M. Bigot has given the following Table relative to Cartouches, and
their Balls._

------------------+---------+---------+---------+---------+------------
Calibers. | 12 | 8 | 6 | 4 |Light Troops
------------------+---------+---------+---------+---------+------------
| lbs. oz.| lbs. oz.| lbs. oz.| lbs. oz.| lbs. oz.
Charge of powder.| 4 0 | 2 ½ | 2 0 | 1 ½ | 0 17
Weight of the | | | | |
cartouch and ball.| 16 11 | 11 2 | 8 ½ | 5 12 | 2 1
Height of the | Inches. | Inches. | Inches. | Inches. | Inches.
charge of powder. | 8-3/12 | 6-9/12 | 6-3/12 | 6-1/12 | 5-1/12
Total height | | | | |
of the cartouch. | 13½ | 11½ | 10-8/12 | 9-11/12 | 7-8/12
------------------+---------+---------+---------+---------+------------

CHAPTER II.

OF MATCHES.

Matches, in artillery, are a kind of rope made of flax, hemp, or
cotton slightly twisted, and prepared to retain fire for the use
of artillery, mines, fire-works, &c. Bigot, (_Traité d'Artifice de
Guerre_, p. 64,) has considered this subject under three heads;
namely, of match-rope, priming fuses or tubes, and quick-match. We
purpose, therefore, in the following sections, to treat the subject
in this order.

_Sec. I. Of Slow Match._

Slow-match may be prepared by different processes. When hemp or tow
is spun on the wheel like cord, but very slack, and made into three
twists and then covered with tow, so that the twists do not appear,
and then boiled in the lees of old wine, a slow-match will be formed
which burns very gradually; but slow-match is commonly made after
the following method: The rope for this match is made of flax, or of
soft well-beaten hemp, thoroughly cleansed from the harder fibres,
and the strands are loosely spun. Three strands are sufficient, which
should not, when formed into rope, exceed one inch and two-thirds
in thickness. It should not be shortened in twisting more than
one-fifth, or one-fourth at most, in order to be firm without being
hard.

The ley or lixivium in which the rope is soaked, is composed of wood
ashes and quick lime; and every hundred pounds of match require fifty
pounds of the former, and twenty-five pounds of the latter. They are
boiled for fifteen hours and are taken out of the tub, piled in heaps
and covered with tow, in which situation they are left to ferment.
Some recommend, in order to improve them, immersing them two or three
times in a nitrous solution, composed of four pounds of saltpetre in
a sufficient quantity of water, to every one hundred pounds of match.

The match is afterwards polished by rubbing it along a hair rope,
which removes all extraneous fibres that would spread fire too
rapidly. Twisting the rope strongly before it is polished, is said to
be a good plan.

Matches are finally dried in the sun, and rolled into pieces of
twenty yards each, (weighing about two and a half pounds); then made
up into barrels or boxes, each of which contains about twenty of
these pieces. Match of a good quality burns uniformly at the rate of
five inches per hour, and its coal terminates in a point that resists
pressure. Match rope may be formed by boiling the rope in water,
containing three pounds of wood ashes, one pound of quicklime, two
pounds of the liquor of horse-dung, and one pound of saltpetre.

In the small work, called _The Bombardier and Pocket Gunner_, there
are three formulæ given for slow-match: The first consists in soaking
light twisted rope in strong ley for three days. It burns three feet
in six hours. The second or No. 2, as made at Gibraltar, by immersing
blue paper in a solution of eight ounces of nitre in a gallon of
water. The No. 3, by soaking rope in a solution of three-fourths of
an ounce of sugar of lead in a pint of rain-water, using a larger
quantity in the same proportion, according to the rope.

The use of the acetate or sugar of lead for the formation of
match-rope, was recommended by a French officer in 1782; and since
that time has been used in France both with and without saltpetre.
The tinder-wood, if soaked alternately in solutions of saltpetre and
sugar of lead, will form a very good match.

M. Rothelet (_Archives des Découvertes_, v, p. 239) has given some
new observations on the use of acetate of lead for the preparation
of combustible match-rope. He mentions the use of liquid acetate
of lead, which may either be a solution of the oxide of lead in
distilled vinegar, or a solution of sugar of lead in water. Rope,
he adds, may be made very inflammable, by soaking it well in the
liquid acetate, and drying it thoroughly. See also the _Bulletin de
Pharmacie_, September, 1812.

Matches may be made very expeditiously by employing sugar of lead
in the following manner: Put a quantity of rain or river water in
a kettle over the fire, and when it boils, throw in sugar of lead
in the proportion of three-fourths of an ounce to a pound of water.
Remove the kettle when the sugar of lead is all dissolved, and
immerse the cord or rope in the solution for ten minutes, and then
take it out and dry it in the air. If cold water is used, the rope
must remain longer in the solution. Rope of every description, old
or new, or that made of the linden bark, and damaged match, may be
submitted to the same process, previously boiling them in common
water to remove their old coating. One pound of solution is required
for each pound of cord.[32]

Ruggeri (_Pyrotechnie Militaire_, p. 185,) has a similar process. The
_salt of saturn_ there recommended, is the same as sugar of lead.

When matches have been made by contract, we may determine their
quality by examining their interior, to see if they are not
mixed with old matches, or pieces of dirty hemp. They should be
sufficiently closed without being either too hard or too loose. The
lixivium should penetrate to their centre; the difference of colour
will indicate the contrary. They should be well dried and partake
neither of mould nor rottenness, which are easily ascertained by the
colour and smell. To be good, the match when lighted should preserve
the fire, and burn uniformly without interruption in moist weather,
so that a piece of five inches in length shall last at least one hour.

In 1808, there appeared in our papers an article on the subject of
_artillery rods_, of which the following is a copy. We re-published
it in the Aurora, of Philadelphia, in the same year, with comments.
Instead of the acetate, nitrate of lead is used.

M. Cadet, of Paris, has invented artillery rods to supersede the
matches in common use. They may be made of birch, elm, poplar, or of
the linden tree. They are saturated with nitrate of lead and undergo
two ebullitions in spirit of turpentine. They then burn very well and
are not extinguished by the air. A _metre_ of each will last an hour
and a half, while the common matches burn only seven minutes. General
Gassendi has made a calculation, which proves, that matches, which
now cost the French government twenty-thousand livres, will not cost
more than fifteen hundred, if made on M. C's new principle.

One pound of rope-match, such as is used in the military academy of
Segovia, lasts nearly thirty-five hours, and rather more provided it
be damp. In that state it is generally surcharged with from six to
seven per cent. of moisture. In short it would be better to dry the
rods in an oven, before they are saturated with the nitrate as well
as afterwards. The following table shows the difference of duration
between the matches made of rope and the new invented rods; and the
quantity of nitrate, each wood absorbs per quintal, is specified in
the last column.

_Woods._ _Durat. per 25 lbs._ _lbs. French_
Cord-match 850 4
Linden, 2400 10
Pine, 2400 42
Cedar, 2400 42
Elm, 2430 19
Oak, 2200 18
Green oak, 1400 18
Walnut, 1400 7
Poplar, 1400 37
Willow, 2400 30

Hence we find that the poplar, pine, cedar and willow, exclude
themselves when compared with the linden tree; since they absorb
three or four times more nitrate than the latter, without burning
longer.

The linden unites the advantages of economy and duration, since it
absorbs only a tenth of its weight. The common oak, elm, walnut
and green oak, occupy but the second rank. We may remark also,
that the hardest woods are not of the greatest duration; for a
rod made of green oak, which is much harder than the common oak,
supports combustion only eight hours, while the latter will burn for
twelve hours. Half a _kilogramme_ of nitrate of lead will saturate
forty-five _metres_ of elm, seventeen of birch; twenty-one of poplar,
and twelve of the linden tree. The woods were cut in parallelepipeds
and boiled in a fish-pan.

MM. Carnot, Guyton Morveau, and Deyeux, were appointed to examine
this invention, who reported favorably. An extract of their report
may be seen in the _Archives des Découvertes_, v, p. 240.

Born also recommends for the same purpose, nitrate of lead, and used
in the same manner. Proust, it appears, repeated the experiments of
Born, and came to the same conclusion;--that it was an expeditious,
and, on a large scale, an economical process for making matches.
Proust, however, used hazle wood. He observes that the solution must
be strong; that when cold it requires three days immersion in the
fluid, and when boiling, only one and a half hours. He also found
that nitrate of copper may be substituted for either the acetate or
nitrate of lead.

_Sec. II. Of Priming Tubes._

Priming tubes, (_fusées d'amorce_) serve to communicate fire to
the powder in a cannon. They were formerly made of tin, but in
consequence of the inconvenience of rusting they were laid aside.
James (_Military Dictionary_, p. 416) remarks, that, owing to this
defect in the tin, a colonel Harding had invented a pewter tube in
lieu of tin tubes. Tubes are used in quick firing. When made of tin
their diameter is two-tenths of an inch, being just sufficient to
enter into the vent of the piece. They are about six inches long.
Through this tube is drawn a quick-match, the cap being primed with
meal powder moistened with spirits of wine. To prevent the mealed
powder from falling out by carriage, a cap of paper or flannel,
steeped in spirits of wine, is tied over it.

They are composed of two distinct parts, the _cravat_ which contains
the priming, and the tube that enters into the touch hole. Small
pieces of well dried reeds or of quills, a little less than the size
of the vent of the piece, are preferred. They are made thus. The
reeds are cut into pieces three inches in length, square at one end
and diagonally at the other, and are passed through a caliber two
and one-third lines in diameter, (the diameter of the vent being two
and one-fourth lines;) they are then rubbed clean in the inside by
passing a small file several times through them, that removes the
inner skin. Having prepared the reeds, they are filled, and also
quills, or other cases, with the composition hereafter mentioned,
made sufficiently thin to enter them. This may be done with the most
facility by placing the cases side by side, with the square end up,
in a tin or wooden box five inches deep; the composition is put into
this, and made to descend into the cases, by knocking the box on
the table. When they are full, they are taken out of the box, wiped
clean, and laid to dry in the sun or in a warm room; before the
composition is entirely dry, a knitting needle is passed from one end
to the other, in order that the fire may reach the bore of the piece
more rapidly. The match of communication (_etoupille_) is then fixed.
This is done by cutting a notch on each side of the reed, near the
end that is cut square, to which two strands of a match, two and a
half inches long, are tied with a fibre of hemp.

The tubes are tied up in packets of ten each, to facilitate their
distribution in service.

The reeds, or other cases, may also be filled in the following way,
_viz_: Take twine made of the strands of cotton thread, and cut into
pieces ten inches long; fold each of these into two lengths, and pass
them through the reed from one end to the other by means of a loop
of very fine thread. The two inches are covered with some of the
composition made thick.

_Composition of Priming Tubes._

_Parts of_, _Meal-powder_, _Saltpetre_, _Sulphur_, _Charcoal_.
Usual composition, 12 8 2 3
Very quick, 4 1 0 0
Particular } 0 13 3½ 4½
composition, } 0 4 ½ ½

The composition is to be moistened with a solution of camphor, &c. in
brandy. To every pint add one ounce of gum arabic, and half an ounce
of camphor. Gum water retards the combustion of the match.

Fifteen pounds of this composition will make ten thousand tubes.

M. Cadet, (_Archives des Découvertes_, i, p. 412) has connected with
the match a preparation of chlorate of potassa, which is inflamed by
sulphuric acid.

We have already spoken of the use of chlorate, formerly called
hyper-oxymuriate, of potassa, in this way. See _chlorate of potassa_.

M. Cadet's invention is as follows: In a glass tube or tube of elder,
is enclosed a match covered with a mixture of chlorate of potassa and
sulphur; above which is fixed a small glass bulb containing sulphuric
acid. This bulb has a small stem of glass similar to that of the
candle cracker, to stick it by into the composition. This match is
placed above the vent or touch hole, and retained there by a socket
of lead. A spring, to which a small hammer is attached, is fixed
to the gun, and is extended and kept in that position by a hook or
bolt. When this is pushed, the spring is unhooked, and by recovering
itself gives a blow with the hammer which breaks the glass ball, and
the acid falls directly on the composition. This is then inflamed
and the fire is communicated to the match, and from the match to the
gunpowder.

A small portion of sugar mixed with the chlorate of potassa and
sulphur, will ensure the composition to inflame with more certainty;
although M. Cadet mentions only the hyper-oxymuriate and sulphur. If
some of this composition, after the priming fuse is charged, be put
in the cup of the fuse, a drop of sulphuric acid will inflame the
fuse.

_Sec. III. Of Quick Matches._

The _etoupille_ of the French is the same as quick match, which is
used to communicate fire in particular in military works, to priming
tubes and other fuses. We have noticed in a former article the
preparation of the matches of communication used in Fire-works, and
the mode of forming leaders for the purpose of conveying fire to the
different parts of a fixed or moveable piece. It will be sufficient,
therefore, to notice the preparation of what is usually called quick
match. These matches are made, according to Bigot, of five strands of
fine cotton thread, soaked twenty-four hours in strong vinegar, and
sometimes in brandy. They are then put, for twelve hours at least,
in a liquid paste, made of meal gunpowder, and spirits, in which
gum arabic and camphor are dissolved, in proportions to be given
hereafter. To make them imbibe this completely, they are pressed with
a pallet knife. They are then taken out and drawn gently between the
fingers to discharge the excess, spread upon a table, and when half
dry, dusted with meal-powder. The match is rolled by hand to make it
round, hung upon a frame, furnished with pins, to dry, and afterwards
cut into lengths of two and a half feet and tied up in bundles.

_Materials necessary to make ten thousand Priming Tubes._

Cotton thread, 5 lbs.
Meal-powder, 3 --
Vinegar, 5 quarts.
Brandy, or other spirits, 3 ----
Gum arabic, 3 ounces.
Camphor, 1½ ----

When matches are required to communicate fire slowly, sulphur and
beeswax, or rosin are added to meal-powder, in proportion to the
degree of slowness required. The cotton, in this case, must have been
soaked in water instead of spirits.

Cotton, 1 lb. 12 ounces.
Saltpetre, 1 -- 8 ----
Spirits of wine, 2 quarts.
Water, 2 ----
Isinglass, 3 gills.
Meal-powder, 10 lbs.

The cotton is then taken out and laid in a trough, where some
meal-powder, moistened with alcohol, is thoroughly wrought into it.
This done, the cotton, being in strands, is taken out separately, and
drawn through meal-powder and hung upon a line to dry.

If worsted in the place of cotton is employed, the proportions then
are,

Worsted, 10 ounces.
Meal-powder, 10 pounds.
Alcohol, (spirits of wine,) 3 pints.
Vinegar, (white wine,) 3 ----

In the preparation of quick match, the following method is sometimes
pursued; _viz._ soak the cotton well in a hot solution of saltpetre;
then remove it and lay it in a trough with some mealed powder,
moistened with spirits of wine, which is to be worked in by the hand.
It is afterwards drawn through meal-powder, and dried upon a line or
reel.

CHAPTER III.

OF PORT FIRES.

Port fires (_lances à feu_) are a species of fuse of a slow
composition, designed for different purposes, and particularly for
guns, when they are to fire rapidly. The paper, is first rolled in
cases. The rod or mandril should be of hard wood, 16 or 18 inches
long, and 5-1/2 lines in diameter. Two brass rods to load them, one
of 17 inches in length, the other of only 8, are required. A wooden
rammer, with a heavy head, may be used. A small funnel with a spout
5-1/2 lines in diameter, and a ladle to lift the composition, are
also required. The instructions of M. Bigot for the formation of
_Port-fire_ are that the paper must be cut in bands, 3-1/2 to four
inches wide, and 15 inches long, and six strips of this paper are
to be arranged on a level table, one above the other in such a way,
that each strip extends about half an inch beyond the next below it,
and pasting the projecting parts of it; that the wooden rod is then
placed upon the upper strip, near the side, and the paper is rolled
several times round it; pressing it at the same time, and shutting
the case, thus formed, at one end, by bending the paper up 3 or 4
lines on the rod, and striking it on the table to flatten it; that
the rod is then removed, and the case is dried, which is afterwards
filled by introducing the composition through the funnel, and ramming
it as fast as it falls down; which is done by alternately raising
and lowering the copper rod, without drawing it entirely out; that
in charging, care must be taken to beat it uniformly, with such a
force, that the paper may not be torn, and the composition equally
solid throughout; that when the composition is within an inch of the
end of the paper case, a tow match is put over it, of 1-1/2 inches in
circumference, the two ends of which project from the paper case, and
are covered with priming paste; and finally, that the port-fire is
finished, by pasting upon its end a small bit of paper, which is torn
off, when the match is to be used.

Port-fires are tied up in a sheet of paper, in parcels of ten.

_Composition of Port-fires._

---------------------------+--------+--------+--------+---------+------
| Meal | Salt- | | |
KINDS OF PORT-FIRE. | powder.| petre.|Sulphur.|Charcoal.|Rosin.
---------------------------+--------+--------+--------+---------+------
To last 12 min. moistened }| 10 | 12 | 6 | |
with linseed oil. }| | | | |
---- 10 do--do | | 19½ | 7¼ | ½ |
---- 7 do--commonly used. | | 19½ | 8 | ½ | ½
---------------------------+--------+--------+--------+---------+------

The articles are pulverized, and mixed by passing them through
fine sieves at least twice. After the addition of linseed oil, the
composition is again mixed with the hand. If too much oil be added,
the port-fire will not keep. Fourteen pounds of composition, and
2-1/2 reams of paper, are required for 100 port-fires.

Port-fires are usually 16-1/2 inches, and seldom more than 21 inches
in length. The paper cases must be rolled, wet with paste. The
distinction, made between what is called the wet, and dry port-fire,
is, that, in the former, linseed oil is used, and, in the latter, the
composition is mixed dry. Dry port-fire, according to the British
formula, is composed of saltpetre 4 parts, sulphur 1, meal-powder 2,
and antimony 1.

The following formulæ for port fire are given in the Pyrotechny of
the Encyclopedia Britannica.

1. Saltpetre 12 oz.
Sulphur 4 --
Meal-powder 2 --
2. Saltpetre 8 oz.
Sulphur 4 --
Meal-powder 2 --
3. Saltpetre 1 lb. 2 oz.
Meal-powder 1½ lbs.
Sulphur 10 oz.
4. Meal-powder 6 oz.
Saltpetre 2 lbs. 2 --
Sulphur 10 --
5. Saltpetre 1 lb. 4 oz.
Meal-powder 4 --
Sulphur 5 --
Sawdust 8 --
6. Saltpetre 8 oz.
Sulphur 2 --
Meal-powder 2 --

_Illuminating port-fires_, used in fire-works for exhibition, &c.
have been noticed heretofore.

The composition of the charge for fire-lances (port-fire,) is thus
given by Ruggeri;

_Substances._ _Proportions._
Saltpetre 16 parts.
Sulphur 8 ----
Powdered antimony or powdered pitcoal 4 ----

Mixed, and passed three times through a sieve.

CHAPTER IV.

OF FUSES FOR SHELLS, HOWITZES, AND GRENADES.

The fusée of the French, is applied to various purposes, and is
differently made by different artificers. Fuses are intended to
communicate fire to the powder with which shells, &c. are filled, so
as to make them burst in the places to which they are thrown. They
are composed, according to some, of one pound of gunpowder, and two
or three ounces of charcoal, well mixed together; or of four pounds
of gunpowder, two of saltpetre, and one of sulphur. It is to be
remarked that the time a bomb, or grenade, will take to burn, after
it has been thrown out of the mortar, or a howitz out of a howitzer,
depends entirely upon the length and quality of the fuse. Fuses are
made of wood turned in the form of a truncated cone, in order to
enter fairly into the _eye_ of the shell. They are perforated through
the middle, in the direction of the axis, so as to receive the
composition. This channel is called the _light_ of the fuse. The wood
that is employed, should be strong, dry, sound, and without knots.
The best kinds are the oak, the elm, and the linden. They are filled
with a slow combustible composition. The materials are increased or
diminished according to the nature of their application. Fuses are
sometimes made of copper.

The fuses for 10 and 12 inch shells are 8-1/2 inches long; for 8 inch
shells, 7-1/2, for howitzes, 5-1/2; and for hand grenades, 2-1/2.
The diameter of the light, in the first is 5 lines, in the second
and third, 4 lines, and 2 lines for grenades. At the larger end of
the fuse for shells, and howitzes, a cup is made from 10 to 14 lines
in diameter, and 3 deep. In turning them, a solid bit, 2-1/2 inches
thick, is left at the small end, to prevent them from splitting,
when the composition is pressed into the canal. When the fuse is to
be driven into the eye of the projectile, this piece is sawn off,
cutting the fuse diagonally. The turner marks its termination by a
circle upon the fuse. Fuses decrease nearly one inch in length, and
two lines in diameter, according to the caliber of the bomb. The
diameter of the lights, or apertures, only diminish half a line.

In what is called the Shrapnel shell, invented by colonel Shrapnel,
the seasonable use of the fuse constitutes one of its principal
advantages. With regard to the American elongated shell, invented
by a gentleman in the Ordnance, we have heard nothing. See _Shrapnel
shell_, &c.

_Sec. I. Of the Method of Charging the Fuses of Bombs or Shells._

Two rammers of copper are required for each of the several calibers
of 12, 10, and 8 inches; the first an inch longer than the fuse, the
second half as long. These rammers are of the same size with the
lights of their respective fuses, and have a head to receive the
blows of a mallet. Only one rod is wanted for the fuses of smaller
calibers.

The first operation is to examine the fuses, to see that they
have no knots or flaws, and are not wormeaten. The artificers
place themselves astride, and facing each other, upon benches of
strong plank, having, between them, a small vessel filled with the
composition, and each one, a small measure. Each artificer takes a
fuse, inserts the small end into a hole, made in the bench, for the
purpose of maintaining it erect, and preventing it from splitting
in the act of charging. He then passes a measure of the composition
into the light, and introduces the first rod, on which he strikes
15 strokes, of equal force, with the mallet. Between every three
strokes, he raises the rod, to make the composition fall. The
ramming of this measure is therefore executed in 5 _vollies_ or
blows. He then withdraws the rod, and introduces a new charge of the
composition, which he beats as before, and so on until the fuse is
half full; after which he makes use of the second rod, and goes on
loading, until the charge reaches within three lines of the cup. He
then takes two strands of quick match, which (after placing them in
the form of a cross, on the top of the fuse) he presses with his rod,
pours some of the composition upon them, and, beating it carefully so
as not to cut the match, he fills the fuse to the top of the cup.

The fuses of howitzes and grenades are charged in the same way; but
the blows are not so heavy as in larger ones, for fear of splitting
the wood.

The fuses being thus charged, the quick match is folded into the cup,
and the opening closed with a bit of cloth or parchment, or very
strong paper, which is tied an inch below the top. This operation is
called _capping_ the fuse. All the fuses for bombs or grenades are
at present furnished with matches. Care must be taken, therefore, to
leave a vacancy of about .27 parts of an inch, in order to fix in
the match. Fuses of grenades are charged with the same precision as
those for bombs, only the blows, as we remarked, should be weaker for
fear of splitting the fuse. Before the little end is driven into the
bomb or shell, care is to be taken to have the end cut slopingly,
without which the communication of the fire with the powder would be
uncertain.

When fuses have been well loaded, and the materials previously well
mixed, they will naturally burn with an equal steady fire, preserving
in general an even length of flame, without splitting, or irregularly
shaking. They may be proved by throwing them into water, tied to
a stone, or by driving them with heavy blows into the earth. They
should not go out in either of these cases. Fuses made with the
composition we shall describe, and for 10 and 12 inch shells, last
seventy seconds. According to the Strasbourg directions, it appears,
that fuses for shells of 12.78 inches should last until you can count
80 or 85, or 70 seconds. Those for bombs 8.52 inches, 65 counts, or
60 seconds, and those for grenades 25 or 30 counts.

Before the fuse is driven into the bomb, the thin or small end must
be cut off, in order that the fire may be easily communicated to the
mass of gunpowder, which is lodged in the bomb. To fire bombs at a
small distance, the fuse must be cut on a longer slant, so that the
bomb may take effect sooner, and may not remain a long time in the
place where it falls, without bursting.

The fuse must be of such a length, as to continue burning all the
time the shell is in its range, and to set fire to the powder as soon
as it touches the ground, which occasions the shell instantly to
burst into many pieces. When the distance from the object is known,
the time of the shell's flight may be computed to a second or two;
which being ascertained, the fuse may be cut accordingly. By burning
two or three, and making use of a watch, or of a string, by way of a
pendulum, to vibrate seconds, we may determine the length of time a
fuse, or any length of a fuse, will take to burn.

In order to preserve fuses for a length of time, and protect them
from moisture, the cap is coated with a composition, or cement, made
of 16 parts of bees' wax, and 4 of mutton tallow; melting the wax
first, and then adding the suet. Some make use of two-thirds wax, and
one-third rosin. The cap of the fuse is dipped in, when the mixture
is half cold, and immediately withdrawn.

-----------------------------------+---------------------------------
| PARTS OF
Composition for the Fuses of +--------+--------+--------+------
Shells, Howitzes and Grenades. | Meal | | Salt- | Char-
| powder.|Sulphur.| petre.| coal.
-----------------------------------+--------+--------+--------+-------
Composition usually employed, | 5 | 3 | 2 |
Quicker composition, | 7 | 4 | 2 |
Another (from Ruggeri) | 14 | 6 | 8 |
Do. Do. | 16 | 7 | 10 |
Do. (English) | 7 | 3 | 4 |
Do. (Strasbourg) for 8.52 bombs, | 4 | 2 | 3 |
Do. (from the Pocket Gunner) lbs.| 2¾ | 1 | 3¼ |
Do. particular (from Bigot) } | | 2⅝ | 6¾ | ⅝
} | | 3⅞ | 9¼ | ⅞
-----------------------------------+--------+--------+--------+-------

The following is the quantity of composition required for fuses, viz:

1000 fuses, for 10 and 12 inch shells, 92 lbs.
Do. do. for 8 inch shells, 53 --
Do. do. for 6 inch howitzes, 33½ --
Do. do. for hand grenades 16 --

_Sec. II. Of Loading Shells, Howitzes and Grenades._

The shells, before they are loaded, are cleansed from any foreign
substances that may be in them; and those which are split, or have
flaws in the eye are rejected; so are also those that are not
well bored, or are eccentric. They are then charged with powder,
introduced into them by means of a funnel. Five or six pounds of
gunpowder are usually put into twelve-inch shells; from three to
five, in ten-inch shells; from one to one and a quarter, into
eight-inch shells; from three-quarters to one pound, into howitzes;
and grenades of all sorts are half filled. The charge of shells is
increased, when they are to burst into a great number of pieces; for
instance, when they are to fall among troops. Incendiary fire-works
are added, when buildings are to be set on fire. Among these are
fire-stone, and incendiary matches.

The charge having been put into these hollow projectiles, a fuse is
introduced into the eye, after it has been cut diagonally at the
smaller end, and the smaller part taken off. It is forced in by
repeated blows of a mallet on the fuse driver, which is laid upon
the cap of the fuse. It ought not to project more than eight or ten
lines in shells, and six or seven in howitzes.

The fuses of loaded shells, howitzes, and grenades are preserved
from wet and fire in the field, by dipping that part of the fuse,
which projects from the surface of the sphere, for the same purpose
as before mentioned, into the following composition. The immersion
must be made, when the composition, after being melted, is half cold.
Either this, or the formula before given, may be used.

_Composition._

Pitch, 31 parts.
Turpentine, 16 ----
Mutton tallow, 1 ----
Linseed oil, 6 ----

Agreeably to the Strasbourg Memoir on Military Fire-works, it
appears, that, fuses being driven into the shell, four threads of
match must be neatly arranged in the cap. Then cap the fuse with
a piece of parchment dipped in brandy; after which, apply round
the fuse, at the eye of the shell, some capping wax when lukewarm.
Then dip all the extreme part of the fuse, down to the shell, in
melted pitch, which you will leave to cool in the shade, in such a
manner, that the shell may neither be exposed to moisture, nor to the
accident of fire.

_Composition of the Pitch._

Black pitch, 4 lbs.
Rosin, 4 --

This pitch serves not only to pitch the fuses of bombs and grenades,
but also to cover the outside of fire-balls and other fire-works,
intended to be preserved.

_Another Composition of pitch for the same Purposes._

Black pitch, 6 lbs.
Linseed oil, 12 oz.

See the preceding section.

_Sec. III. Of Fuses with Dead Light._

The _feu mort_, or dead fire fuse, is a peculiar species of fuse. The
difference, between these fuses and the ordinary kind, consists in
this, that the eye, instead of being pierced and hollow, is full, and
of a hemispherical shape. In both cases, however, the composition is
introduced through the small end.

_Composition for dead light._

Meal-gunpowder, 16 parts.
Ashes of wood, 9½ ----

The ashes must be dried, and run through a sieve. Potters' earth, or
clay, will produce the same effect as the ashes.

In proceeding to charge a bomb-fuse that is made of ordinary wood,
the eye, or aperture, is first closed with pipe clay, which is well
beaten and pressed against the fuse in a small platter; the thin
end of the fuse being held upwards. Three lines (3/12ths of an
inch) of this earth will be sufficient to stop the communication
of any fire. A tube, or trundle, filled with meal-powder, for the
purpose of setting fire to the composition called _feu mort_, is
thrust into the fuse, by which it is finally charged. If this
charge of meal-gunpowder were to be omitted, the fuse might not be
susceptible of ignition; but the quantity never ought to exceed three
lines, as the fuse would split by the explosion. When the grains of
gunpowder have been well pounded, a trundle or tube, filled with the
aforementioned composition, must be applied, and it is finally loaded
like the rest.

It must be recollected, that two inches of this composition will
last as long as one of the quality, with which common fuses are
charged. Before the fuse is driven into the bomb, it must be pierced
through with a gimblet of one line in diameter; taking care, that
the hole is made precisely through the charge of meal-powder. One
end of a priming match must be forced in, and three others be tied
to it, which three are to fall upon the bomb, when it lies in the
mortar. The particular object to be obtained by this kind of fuse,
is to prevent the least trace of fire or light being visible in its
projection; so that the enemy may remain ignorant of the range, or
direction of the bomb, and not be able, of course, to get out of the
way when it falls, or to avoid the effects of its explosion.

These fuses were made use of at the siege of Ham in 1761. The
experiments, which were made, in 1792, with this composition, by an
artificer belonging to the ordnance board, at Douay, have proved,
that it answers every purpose, for which it was invented.

The author of the _Manuel de l'Artilleur_ observes, however, that
the advantages to be derived from this invention, are not so great
as they first appear. He remarks, that, with respect to the real
utility of the fuse _à feu mort_, if it be considered as tending
materially to the defence of any beseiged place, the argument cannot
be very forcible, when we reflect, that to gain time constitutes one
of the principal means of defence, and that the only way to obtain
it, is by retarding the beseigers' operations. These ends are gained
by various expedients. Among others, the common lighted fuse conduces
not a little: since, during the whole direction of the bomb against
the works of the assailants, the attention of the workmen is diverted
from their immediate labour; and as long as it continues in its
range, much uneasiness is created, because its ultimate explosion and
concomitant destruction are unknown. Add to this, that, independent
of the confusion that is occasioned among the assailants by repeated
projectiles, the bombardier, by means of lighted fuses, is enabled to
correct his aim during the darkest night. This kind of fuse has been
known for many years, and, it is presumed from these objections to
its use, the common fuse has been hitherto adopted.

_Sec. IV. Of the Dimensions of Fuses, and the Dimensions and Charge
of Bombs, Howitzes and Grenades._

Shells, in gunnery, are hollow iron balls, to be thrown out of
mortars or howitzers, with a fuse hole of about an inch in diameter,
to load them with powder, and to receive the fuse. The bottom, or
part opposite the fuse, is made heavier than the rest, that the fuse
may fall uppermost. In small elevations, this is not always the case,
nor is it necessary.

Shells are called hollow projectiles, and, besides powder, various
incendiary matters are introduced; but in addition to shells,
properly so called, hollow projectiles comprehend howitzes and
grenades. As a principle, it is observed, that their sides ought to
be proportionably thick to the shock they receive in the piece, and
to the quantity of powder introduced for bursting them; and their
weight, according to the objects they are to destroy. We remarked,
that a shell should be thicker opposite the fuse. This thickness is
called by the French a _culot_, or reinforcement of metal; the object
of which is to prevent the breaking of the shell on rocks or stone,
as well as to prevent its falling on the fuse. Four times as much
powder may be put in the cavity as is sufficient to burst them. This
admits the introduction of incendiary matter. Howitzes are hollow
balls with a _culot_, or reinforcement of metal, upon the inside,
opposite the eye, and are calculated for ricochet, that is, for
passing, bounding, over the ground, and, by striking and penetrating
solid objects, and finally bursting, produce considerable havoc and
devastation. For ricochet, the howitz, in fact, should be of the same
thickness throughout.

Grenades are also a hollow ball, and are of two kinds; namely, the
rampart or ditch grenades, of the caliber of 36, 24, 18, and 12
pounders, designed for rolling along a trough from the top of the
rampart, and falling into the ditch, to annoy an enemy, in attempting
to cross it; and the hand-grenade, that are thrown by hand into
the interior of works, that are attacked, into covered ways and
trenches, &c. They are of six and three pounder calibers, and their
splinters will fly 35 yards. Grenades were invented about the time
that shells were, and first used in 1594. Grenades have sunk into
disuse; but they may be advantageously employed. During the seige
of Cassel, under the count de la Lippe, in the campaign of 1762, a
young engineer undertook to carry one of the outworks, with a small
detachment of men by using grenades, and in consequence succeeded.

Message shells are nothing more than howitzer shells, and are so
called, because they are used to carry letters or papers. During the
bombardment of Flushing, and while the communication with Cadsand
was cut off, means were found to convey a letter from the garrison
into the latter place. It was inclosed in a shell without inflammable
matter, and discharged from a mortar, planted on one of the sea
batteries.

Shrapnel shells were invented by colonel Shrapnel of the British
service. They were used, we are told, with peculiar effect against
the French, in 1808, and at the battle of Waterloo in 1815. The fuses
for these shells, after being turned so as to fit the fuse-holes,
are bored, and a deep thread grooved inside, to hold the composition
firm; and, instead of being turned with cups, they are hollowed
conical, and roughed with a tool that cuts under, the better to
receive the priming. After they are driven, with fuse composition,
one and a half inches, they are sawed across the top about one-fifth
of an inch down, so as not to touch the composition, and divided into
five equal parts, of two-tenths of an inch each; after which, a bit
of quickmatch is placed across, and drawn tight in the same grooves.
They are then primed with meal-powder and spirits of wine, capped,
and packed for service.

We here insert three tables, which we have extracted from the work of
M. Bigot.

The first table is relative to the dimensions of fuses for shells,
howitzes, and grenades; the second, respecting the dimensions of
bombs, howitzes, and grenades; and the third, of the charge of bombs
and howitzes.

These tables, taken together, will exhibit all the particulars on
this subject; and as this kind of data is necessary, in the practical
operations of the laboratory, their introduction in this place, we
consider important.

_Table relative to the Dimensions of Fuses for Shells, Howitzes, and
Grenades._

-----------------------------+-------+-------+---------+--------------
| | | | Grenades.
CALIBERS. |12 and |8-inch.|howitzes,+--------+-----
|10-inch| | 6-inch. |Rampart.|Hand.
-----------------------------+-------+-------+---------+--------+-----
| inch. | inch. | inch. | inch. | inch.
Length, | 9 | 8 | 5½ | 4 | 2½
Diameter. | | | | |
At the large end, | 1⅔ | 1⅓ | 1¼ | 11/12 | ⅔
At 3 inches from the large | 1⅓ | 1 | 11/12 | 0 | 0
end, | | | | |
At the small end, | 1⅙ | 11/12 | 10/12 | ¾ | ½
Of the light, | 5/12 | ⅓ | ⅓ | ¼ | ⅙
Of the interior of the cup,| 1⅙ | 11/12 | ⅚ | 7/12 | 5/12
Depth of the cup, | 3/12 | 3/12 | 3/12 | 3/12 | 3/12
Height of the massive, | 5/12 | 5/12 | ¼ | ¼ | 0
-----------------------------+-------+-------+---------+--------+-----

_Table of Dimensions of Bombs, Howitzes, and Grenades._

----------------------------+--------+--------+--------+--------+--------
| | | 8-inch,| |
CALIBER. |12-inch.|10-inch.|& howitz|howitzes| Hand
| | | 8-inch.| 6-inch.|grenades
----------------------------+--------+--------+--------+--------+--------
|inch. |inch. |inch. |inch. |inch.
| lines.| lines.| lines.| lines.| lines.
| pts.| pts.| pts.| pts.| pts.
Diam.{of bombs, | 11 10 6| 10 0 0| 8 1 6 | 6 0 0 | 3 6 0
{of the light{exterior,| 1 4 0| 1 4 0| 1 0 0 | 0 11 0 | 0 8 6
{interior,| 1 3 0| 1 3 0| 0 11 0 | 0 10 9 | 0 8 0
Thickness {of the sides, | 1 6 0| 1 6 0| 0 11 0 | 0 11 0 | 0 4 0
{of the culot, | 2 2 0| 1 4 0| 1 3 0 | 0 0 0 | 0 5 0
| Pounds.| Pounds.| Pounds.| Pounds.| Pounds.
Weight of the bombs, { | 145 to | 97 to | 43 to | 20 to | 3¼
{ | 150 | 100 | 45 | 25 | 0
----------------------------+--------+--------+--------+--------+--------

The rampart grenades are variable in their dimensions, and weigh from
eight to twelve pounds.

_Table of the Charge of Bombs and Howitzes._

-----------------+-------------------------------+-----------------------
| Bombs of | Howitzes.
+---------+---------+-----------+-----------+-----------
|12-inches|10-inches| 8-inches. | 8-inches. | 6-inches.
-----------------+---------+---------+-----------+-----------+-----------
Charge | | | | |
of full bombs, | 17 lbs. | 10 lbs. |4 lb. 1 oz.|4 lb. 1 oz.|1 lb. 6 oz.
sufficient to }| | | | |
burst them. }| 5 | 3 |1 |1 |0 12
-----------------+---------+---------+-----------+-----------+-----------

CHAPTER V.

OF INCENDIARY FIRE-WORKS.

Under this head are included all artificial preparations, designed,
as the name expresses, to communicate fire to buildings, shipping,
&c. and for other purposes, connected with the operations of war.

At different periods, even from the remotest antiquity, incendiary
works have been used. Of these preparations, we may enumerate the
following: shells, howitzes, and grenades; fire-stone to put into
shells and howitzes, intended to produce conflagration; incendiary
matches, used in the same manner; carcasses and fire balls, to be
thrown from a mortar, designed to light up the works in front of a
besieged fortress, and to burn buildings; incendiary, or fire-balls,
to be thrown from cannon or by hand, used in besieged fortresses
to light up the enemy's works; pitched tourteaux and fascines, to
illuminate the passage of rivers and defiles; powder bags, to throw
upon troops mounting to the assault; powder barrels, to roll from
the top of a breach, or from the head of a sap from the glacis;
thundering barrel, employed for the same purpose; burning or
illuminating barrel; petard, to break down the gates and barriers
of small towns, and even thin walls; torches or flambeaux, to give
light during night marches, and other purposes; rockets, fougettes,
and murdering and the Congreve war rocket, for various uses;
rocket carcass of Congreve, as an incendiary; rocket light ball,
to illuminate the horizon near the enemy; murdering marrons; Roman
incendiary candles, and incendiary stars; tarred and pitched ropes;
fire rain; marine fuses, &c. to which we may add the ancient Greek
fire, and red-hot balls.

In this chapter, under the different heads, we purpose to describe
these, and other fire-works, used in war. We may remark, also,
that animals are sometimes used as incendiary agents. _Rats_,
for instance, have been employed in certain enterprizes, as for
the purpose of setting fire to magazines of gunpowder. On these
occasions, a lighted match is tied to the tail of the animal. The
_courier pigeon_ of the French, or carrier pigeon, is not used in
this way; but only as a carrier of letters, to which it is trained
and used in Persia and Turkey.

_Sec. I. Of Fire Stone._

The fire stone (_Roche à feu_) is a compact, or solid composition. It
is calculated to burn slowly, and when put into shells and howitzes,
and thrown into cities, produces conflagration.

This stone is composed of sulphur, saltpetre, meal-powder, and
sometimes grain-powder, &c. The sulphur is melted in a kettle, or
glazed earthen vessel, over a clean charcoal fire; the saltpetre
being pulverized, is then thrown into it, and the spirits of
turpentine, if any is used. These articles are stirred with a
spatula, and the fire must be so regulated, as to prevent the
composition from boiling over, or taking fire. When these are well
melted and mixed, they are taken off the fire, and permitted to cool
a little; the gunpowder is then thrown in, and the composition poured
upon a cold surface, where it consolidates. It is then broken into
small lumps, to be made use of when required.

We may here remark, that, as the goodness of this composition depends
upon the accuracy with which the mixture is made, too much care
cannot be paid to this circumstance.

For the purpose of rendering this incendiary more inflammable, it is
recommended to roll the pieces in meal-powder, before they become
fully hard. If the same composition be mixed with suet and spirits
of turpentine, it is used for the same purpose, but not in the same
manner.

The invention of the fire stone is said to have originated from
the fire-rain of Casimir Siemienowicz, an ingenious Polander, and
Chevalier of Lithuania, &c.; and in fact, according to Ruggieri, the
composition was taken from his treatise.

Incendiaries to be put into bombs or shells, are sometimes in rolls
in the form of a _sausage_, which continue to burn after the shell
has burst. They infallibly set fire to whatever combustible substance
they touch. When thus made they are from .88 parts of an inch, to an
inch in diameter, and from 3 to 4 inches long. Carcass composition is
generally used. It is run into cylinders, which are pierced in the
middle, and the hole is filled with the composition of bomb fuse.
They are also furnished with cotton matches.

_Composition of Fire Stone._

-----------------------------------------------------------------------
| PARTS OF
+----------------------------------------
|Sulphur.|Salt- | Meal |Powder |Char-
| | petre. |Powder.| in | coal.
| | | |grain. |
------------------------------+--------+--------+-------+-------+------
Composition frequently made } | 16 | 4 | 4 | 3 | 0
use of, } | | | | |
Do do do | 28 | 5 | 4 | 4 | 0
Do for particular purposes, | 9¼ | 16⅞ | 0 | 0 | ⅞
Do do do | 11 | 29 | 0 | 0 | 1
Do do (spirits of } | | | | |
turpentine, 12 oz.) and } | 6 | 1 | 4 | |
------------------------------+--------+--------+-------+-------+------

Fire stone may be considered the _wild-fire_; but this term is
applicable to any composition, as the Greek fire, which, when
inflamed, burns with rapidity, and communicates its fire to
surrounding objects with quickness. In such cases, the combustion
is so rapid, that buildings, &c. are immediately wrapt in flames,
which seem almost to defy all human power to extinguish. Such was the
nature of the Greek fire, of which we shall speak hereafter.

_Sec. II. Of Incendiary Matches._

These are better for the purpose of putting into shells and howitzes,
than fire-stone alone, which does not burn as well. Their preparation
consists in boiling common slow match in a solution of 20 parts of
saltpetre, in six parts of water; then drying and cutting it into
pieces of two or three inches long, and immersing it into fire-stone,
in a state of fusion. Before the match has become solid, let it be
rolled in meal-powder, or in grain powder. Fifty pounds of fire-stone
will be sufficient for 1500 matches.

_Sec. III. Of Carcasses and Fire-Balls._

Carcasses and fire-balls are made of a composition of combustible
substances, and are used to produce light, as well as to fire
buildings. The difference between them is, that the carcass has bands
or hoops of iron, that form its shell. These hoops are made at right
angles with each other, in an oval form, and fastened together with
a base of iron. The fire-ball is made of a sack of strong tow cloth,
or of a bag of basket work, in an oval form, and covered with strong
cord, to give it a body. Both, however, are well wrapped with cord,
to make them more solid.

The Rev. J. P. Coste, in 1794, invented a carcass composition, which
he submitted to the French national convention. It appears that its
fire was very violent, which nothing could extinguish, and could be
thrown 800 paces from a caliber of 24 in. and to a greater distance,
if required. An account of this carcass is given in the _Moniteur_,
No. 342.

Oblong carcasses were formerly in use. The round carcass is more
applicable for mortars and howitzers. The 13-inch round carcass
weighs about 212 lbs., 10-inch 96 lbs., 8-inch 48 lbs., and
5-1/2-inch 16 lbs. Carcasses are seldom or ever fired from guns or
carronades, in the land or sea service. In bomb vessels, they are
only fired from mortars. After the first invention of bombs, that of
carcasses and grenades naturally followed. They are said to have been
first used in 1594, and afterwards by the bishop of Munster, at the
siege of Groll, in 1672, where the Duke of Luxemburg commanded.

The carcass for 12 and 10-inch mortars has six bands of iron; that
for an 8-inch mortar, no more than four. These bands are of an
oval shape, and fixed with nails, either clenched or rivetted to a
bottom, of the shape of a segment of a sphere; then to a hoop, placed
horizontally at one-third of their height; and at top, to another
that closes the opening.

The sacks, that contain carcasses and fire-balls, are of a
cylindrical form, and their diameter and height are equal, being the
same as that of the carcass at one-third its height. They are sewed
upon a circular bottom, like the woollen bags of gun-cartridges. When
the ball is wound with thread, the folds will disappear. The sacks of
fire balls are an inch less than the caliber of the mortar, and those
of carcasses four inches more.

_Table relative to the Dimensions of Carcasses, to fire from the
Mortar._

------------------------------------------+---------+---------+--------
CALIBERS OF | 12-inch.| 10-inch.| 8-inch.
------------------------------------------+---------+---------+--------
The spherical segment. | Inch. | Inch. | Inch.
{ radius, | 5-5/12 | 4⅔ | 1
{ height, | 2 | 1⅔ | 1
| | |
Diam. of the circle, { at ⅓ of the height | 10 | 8½ | 7
{ at the opening | 6 | 5 | 4⅙
| | |
{ Of the iron mounting | 12 | 10 | 8
{ Of the charged carcass, the } | 16 | 14 | 12
Height { ear not included } | | |
{ Of the enveloping sacks | 16 | 14 | 12
| | |
The weight of the iron, for the mounting }| Pounds. | Pounds. | Pounds.
of the carcass, about }| 20 | 18 | 7
------------------------------------------+---------+---------+--------

_Composition of Carcasses and Light Balls._

----------------------+--------------------------------------------
|Pitch.
| |White Pitch. (Turpentine.)
| | |Mutton Tallow.
| | | |Rosin.
| | | | |Sulphur.
| | | | | |Saltpetre.
| | | | | | |Grain-powder.
| | | | | | | |Meal-powder.
| | | | | | | | |Camphor.
| | | | | | | | | |Charcoal.
| | | | | | | | | | |Carabé.
----------------------+--+----+--+--+----+----+--+--+--+---+-------
Moist composition. |24| 12 | 4| 0| 0 | 0 |36| 0| ½| 0 |0
Idem. |18| 0 | 1| 0| 0 | 0 |30| 0| 0| 0 |0
Dry composition. | 0| 0 | 0|12| 1 | 2 | 0| 2| 0| 0 |0
Idem. | 0| 0 | 0|12| 2½| 11 | 0| 0| 0| 1½|0
| | | | | | | | | | |
Another. |12| 6 | 2| 0| 0 | 0 |30| 0| ½| 0 |0
Ditto. | 0| 0 | 1|12| 0 | 2 |20| 0| 2| 0 |1
Ditto. |12| 0 | 3| 0| 0 | 6 |30| 0| 0| 0 |0
Ditto. |15| 0 | 3| 0| 0 | 6 |30| 0| 0| 0 |0
Ditto. | 0| 2½| 0| 1| 1 | 1½| 0| 2| 0| 0 |0
Ditto, particular, } | | | | | | | | | | |
for setting fire } | 0| 0 | 0| 1| 4 | 2 | 0|10| 0| 0 |0
to magazines, } | | | | | | | | | | |
buildings, &c. } | | | | | | | | | | |
Ditto, same purpose. | 0| 0 | 0| 4| 16 | 32 | 0|48| 0| 1 |0*
Ditto. do. | 7| 0 | 1| 6| 6 | 0 | 0| 8| 0| 0 |0
| | | | | | | | | | |Antim.
Ditto. do. | 5| 0 | 0| 8| 25 | 50 | 0| 0| 0| 0 |5
----------------------+--+----+--+--+----+----+--+--+--+---+-------

* Also, iron or steel filings, 2; and fir-tree sawdust boiled
in a solution of saltpetre, 2.

We may remark, that the four first formulæ are given by Bigot, and
are used in the French service. Therefore, although the others have
been employed, we may consider the proportions in these, as best
adopted for the carcass and light-ball composition. About 49 lbs. of
composition and two lbs. of fine tow, are required for a carcass of
12 inches.

Luminous or light balls are sometimes made of the following
compositions.

_Composition for Luminous Balls._

1. Sulphur 6 oz.
Antimony 2 --
Saltpetre 4 --
Rosin 4 --
Charcoal 4 --

2. Saltpetre 2 oz.
Rosin 2 --
Charcoal 2 --
Antimony 1 --
Sulphur 1 --
Pitch 1 --

In the formation of luminous, or light balls, whatever may be the
composition, we may remark, that the only ingredients which appear
to be essentially necessary are nitrate of potassa and inflammable
substances. In some preparations, antimony is used, for the same
reason as in the Bengal lights. Rosin, pitch, and charcoal are all
inflammable; and sulphur, although it takes fire more instantaneously
than these, enters into the composition of such fires more on account
of its flame than any other.

As a general rule for the preparation of carcass composition, the
following particulars must be attended to. After melting the pitch,
turpentine, rosin, and sulphur, add the tallow and camphor, and then
the nitre and charcoal, in powder. They are then to be stirred,
and mixed intimately. Care must be taken to regulate the fire, and
prevent the composition taking fire. After the kettle is withdrawn
from the fire, the gunpowder is then gently added, and stirred with
a stick or spatula. The kettle is then again put over the fire, and
afterwards withdrawn. Tow is now added in small quantities at a time,
stirring the mixture well that it may be thoroughly incorporated.

The preparation of the carcass, or fire-ball, is as follows;
observing, that, if it is a carcass, the iron-frame must be first
placed in the sack. Four cords are taken, each four lines in
diameter, four feet long for the calibers of 10 and 12 inches, but
only 3 feet for the calibers of 8 inches.

The middle of these four cords are laid one upon the other in the
form of an eight-pointed star. Each end of the ropes is then fixed
to a nail, and a bottom is formed, similar to basket-work, by
interlacing a cord, two lines in diameter, three or four times round
the central point. The small cord is then tied with a knot, and
the bottom of the basket completed, by tying the four large cords
together with four half knots. The bottom of the sack, containing
the iron carcass, or of an empty sack, if a fire-ball is to be made,
is placed upon the middle of this, and the filling performed in the
following manner, namely: A sufficient quantity of the composition
is taken from the kettle to fill the empty carcass, or sack, three
or four inches high; a few loaded grenades, with the fuse down, or
a howitz placed in the same way, are laid upon this first layer.
The filling is continued to the top, putting the composition and
grenades, in alternate layers. When it is done, the sack is tied with
twine. In order to tie up the fire-ball in its cord net, the cords
are raised from their nails, over the sack, and tied in such a way as
to suspend it about the height of a man's head, and to permit it to
be easily turned round. An artificer fixes the end of a small cord
to one of the larger ones, at the distance of 1-1/2 inches from the
bottom; he makes a half knot upon this, and carries the small cord
round to the others, to which he ties it in the same way, forming a
spiral round the ball. The large cords are kept regularly stretched
in such a way, that each turn of the spiral may be 1-1/2 inches from
that beneath it. When the spiral has reached the top of the ball, he
unites the small cord, called the traverse, with the ends of the four
others, called uprights. He divides the latter into two parcels, and
forms a loop of them, through which a lever may be passed for the
convenience of carrying it. At two or three inches from the upper
end, and upon two sides, diametrically opposite to each other, two
pins of hard dry wood, well greased, are driven in. These pins are 6
inches in length, one in diameter at the head, and half an inch at
the point. They must be inclined in such a way, as to meet in the
axis of the fire ball, at about half its height.

The carcass or fire-ball, when finished, is dipped into the following
composition:

_Composition of Pitch for Fire-Balls._

Pitch, 32 parts.
Turpentine, 16 ----
Rosin, 8 ----
Linseed oil, 6 ----
Mutton Tallow, 1 ----

Grenades answer the purpose of dispersing the fire of the carcass
in different places; and the shell will not burst, till the carcass
has burnt for a sufficient length of time. Sometimes the ends of gun
barrels, or pistols, loaded with ball, are put in.

Carcasses and fire-balls are primed before they are used, by drawing
out the pins, and filling the holes with the composition for the
fuses of shells; taking care to use for ramming, only wooden or
copper rammers. Four cotton matches are placed in each hole, 6.4
inches long, in order to convey the fire.

Carcasses and fire-balls are discharged from mortars, in the same
manner as a bomb. When the carcass is intended to give light to
discover the enemy's works, then the small charges are to be put
into the chamber of the mortar, and but little elevation given, for
fear it should bury itself in the ground. If, on the contrary, the
intention is to set fire to houses or magazines, a greater elevation
is given to the mortars, in order that it may reach and destroy the
buildings, upon which it is intended to fall.

The composition used by the Austrians at the siege of Valenciennes,
which is called after it, has the same effect as carcass. It is
composed of saltpetre 50 parts, sulphur 28, antimony 18, and rosin 6.

An English writer observes, that the best way of making light balls,
is to take thick brown paper, and make a shell the size of the
mortar, and fill it with a composition of equal parts of sulphur,
pitch, rosin and meal-powder.

Before closing this article, we may add, that carcasses are sometimes
made to weigh two hundred and thirty pounds, and those for the naval
service differ from a shell only in the composition, and in the four
holes, from which it burns when fired.

_Sec. IV. Of Incendiary Balls, or Fire Balls, to be thrown from
Cannon or by Hand._

Balls of this kind are employed chiefly in beseiged fortresses to
light up the enemy's works. In order to burn ships, hollow balls
filled with incendiary matter and red-hot shot are preferable.

_Composition of Incendiary Balls._

-------------------------------+----------------------------------------
|_Meal-powder._
| |_Saltpetre._
| | |_Sulphur._
| | | |_Rosin._
| | | | |_Tallow._
| | | | | |_Alum._
| | | | | | |_Antimony._
| | | | | | | |_Charcoal._
-------------------------------+---+---+-----+---+---+---+---+----------
Ordinary composition, moistened| | | | | | | |
with spirits and linseed | | | | | | | |
oil, meal, | 4 | 4 | 3½ | ¾ | 0 | 0 | 0 | 0
Another, | 8 | 8 | 24 | 0 | 4 | 2 | 1 | 0
Do. | 0 | 7 | 4 | 3 | 0 | 0 | 0 | ½
-------------------------------+---+---+-----+---+---+---+---+----------

The first composition is reduced to a paste with good brandy or other
spirits, in which gum arabic and camphor have been dissolved; and
after leaving it a few hours to dry, moisten it with linseed oil, and
make it into balls a little less than the calibers of the guns, from
which they are to be fired or weighing about four pounds, if they
are to be thrown by hand. They are tied up in a cloth and steeped
in a bath of pitch in the same way as carcasses. They are usually
covered a second time with cloth and dipped in the same way. If they
are to be fired from guns, they are enveloped in a netting of wire,
to prevent them from being broke by the action of the charge. These
balls when fired are put down over a small charge without ramming.
Two holes are made in them in the same way as in carcasses and fire
balls and they are primed in the same manner.

In employing the second and other compositions, the materials must
first be melted, such as rosin, tallow, and sulphur, and the powder,
alum, and antimony, added; when the melted matter is removed from
the fire. After they are all mixed, the mixture is then poured into
wooden moulds of two pieces, that are greased on the inside; the ball
is taken from the mould when cool, and wrapped up in cloth or in tow.
It is dipped in melted pitch. When it is to be used, holes are made
in it with a gimblet, and it is primed like the others.

We may remark here, that the Congreve incendiary rocket is armed with
carcass composition, which produces all the effects of the usual
carcass. The rocket carcass will be considered under the head of
war-rocket.

_Sec. V. Of Smoke Balls._

Smoke balls are composed of the same substances as carcasses and
light balls, with this difference, that they contain five to one of
pitch, rosin, and sawdust. This composition is put into shells made
for the purpose, having four holes to let out the smoke. Smoke balls
are thrown out of mortars, and continue to smoke from twenty-five to
thirty minutes.

_Sec. VI. Of Stink Balls._

Stink Balls are prepared with a composition of mealed powder, rosin,
saltpetre, pitch, sulphur, rasped horses' and asses' hoofs, burnt in
the hoof, assafœtida, seraphim-gum, stinking herbs, &c. made up into
balls in the same manner as light-balls, according to the size of the
mortar, out of which they are to be thrown.

_Sec. VII. Of Poisoned Balls._

With respect to poisoned balls, we are informed, that, although they
have not been used by European nations, the Africans and the Indians
have always been very ingenious at poisoning several kinds of fire
compositions. At the commencement of the French revolution, poisoned
balls were exhibited to the people, pretended to have been fired by
the Austrians, particularly at the seige of Lisle. They contained
glass, small pieces of iron, &c. and were said to be mixed with a
greasy composition, which was impregnated with poisonous matter. In
1792, they were deposited in the archives of Paris.

Poisoned balls, according to authors, are composed of meal powder
four parts, pitch six, rosin three, sulphur five, assafœtida eight,
extract of toads' poison twelve, other poisonous substances twelve,
made into balls in the manner we have mentioned. See _Poisoned Arrow_.

_Sec. VIII. Of Red-hot Balls._

It will be sufficient to observe, that red-hot shot, as an
incendiary, are considered fully adequate to perform the effect which
they are designed to produce. The balls are ignited in a coal fire on
an iron grate, in a furnace constructed for the purpose; and, when
thus heated, are thrown from guns, the space between the powder and
ball being filled up with a piece of wood of the exact diameter of
the gun, or with wet hay or grass, to prevent the ball from setting
fire to the powder.

With respect to chain balls, composed of two balls linked together
by a chain from twelve inches to four feet in length, and designed
to destroy palisadoes, wooden bridges, and chevaux-de-frize of a
fortification; stang-balls, or bar-shot, called by some, balls of
two heads, made by uniting, by means of a bar, half shot; and anchor
balls, filled with the same composition as light-balls, with some
trifling variation in the ball itself, &c.--they are all used as
destructive weapons, which belong more particularly to the service of
artillery.

_Sec. IX. Of Pitched Tourteaux and Fascines._

Tourteaux are employed to illuminate the passages of rivers and
defiles. They are placed in portable _lanterns_ or in fire-grates.
They are used chiefly to light up the works of the beseiger, when
he approaches the covert way, and to burn the gabions and fascines,
with which he constructs his passage to the ditch. Tarred links are
nothing more than old junk or matches, dipped into a composition of
pitch, suet, linseed oil and turpentine; the junk being cut into
lengths of about five feet, which is called a link. The _Tourteaux
goudronnés_ of the French are the same, and formed of old rope, which
is untwisted, immersed in pitch or tar, and afterwards left to dry.
The French make the _Tourteaux goudronnés_ in the following manner:
Take twelve pounds of tar or pitch, six pounds of tallow, and three
pints of linseed oil; melt them together and dip twisted pieces of
rope of any length into the boiling mixture. If they are required
to burn slow, six pounds of rosin and two pounds of turpentine are
added. Sometimes to the composition of pitch, tallow, and linseed
oil, are added two parts of saltpetre, one part of sulphur, and
half a part of antimony. Tourteaux, according to Bigot, are made
in the following manner: Old cords or pieces of match are beaten
with mallets to take out the dirt, and prepare them to receive the
composition. They are untwisted a little for the same purpose.
They are then cut into pieces about five feet in length, and each
is intertwined to form a circle of five or six inches of external
diameter, making a hole at the same time in the middle for the
passage of the point of the lantern.

The rope, being thus prepared, is next boiled in the composition
given below, for the space of ten or fifteen minutes, and then laid
upon a wet plank. They are a second time dipped into the composition,
and thrown into cold water, to give them again, by hand, the circular
figure they may have lost. Flower of sulphur is now put over them,
and they are dried in the shade.

_Composition for Tourteaux._

Pitch, 24 parts.
Turpentine, 12 ----
Rosin, 6 ----
Mutton tallow, 4 ----
Linseed oil, 1 ----
Venice turpentine, 1 ----

_Another, for Tarred Links and Fascines, according to the Strasbourg
formula._

Pitch, 18 parts.
Turpentine, 9 ----
Suet, or tallow, 4 ----
Linseed oil, 1 ----
Spirits of turpentine, 1 ----

When a great quantity of links are to be made, either for
illumination or for lighting a city, the oil may be omitted. The
links will cost less, and they will answer the purpose equally well.

Fascines are made of strips of wood, or dry twigs, or wine shoots,
which are the best, of the length of fourteen or sixteen inches. They
are tied in bundles of four or five inches in diameter, with a cord
or iron wire, and then boiled in the composition for tourteaux, and
thrown into water to cool. They are principally used to give light to
the works of an enemy, and to set fire to the passage of the ditch.

Fascines are of different kinds. In fortification, they are a kind of
fagot, made of small branches of trees or brush wood, tied in three,
four, five, or six places, and are of various dimensions, according
to the purposes intended. Those that are to be pitched over for
burning lodgements, galleries, or any other work of the enemy, should
be one and a half or two feet long.

_Sec. X. Of Torches or Flambeaux._

We have already spoken of torches, but in connection with military
pyrotechny, we may add, that they are used to give light during
night marches, and for other purposes. They are made in the following
manner.

Boil, in a mixture of equal parts of water and saltpetre, old cords
or old match, well cleaned and untwisted. Take them out and dry them;
then cut them in pieces of four and a half feet in length, and tie
four of these pieces with twine to a cylindrical piece of wood, of
the same length, and an inch in diameter; so that the whole together
may be from two to two and a half inches thick. Dip this torch into
a liquid made of equal parts of meal-powder and sulphur, mixed
together with brandy, in which some gum has been dissolved. Fill the
intervals of the pieces of cordage, with a paste, composed of three
parts of sulphur, and one of quicklime. Dry the torch, and when dry,
turn it gently round, and finish it by pouring on it the following
composition.

_Composition for Flambeaux._

Turpentine, 32 parts.
Venice turpentine, 4 ----
Beeswax, 32 ----
Sulphur, 12 ----
Camphor, 6 ----

_Another._

Pitch, 6 parts.
Turpentine, 6 ----
Venice turpentine, 1 ----

Torches or flambeaux may also be made without the central piece of
wood.

Torches ought to have the quality of burning, let the weather be what
it may. The following method of making them is also recommended.

Take four large cotton matches, three or four feet long, boil them
in saltpetre, and arrange them round a pine stick; after which cover
them with priming powder and sulphur, made into a thin paste with
brandy. When dry, cover the matches with the following composition;
viz. 2 lbs. of yellow wax, as much white pitch, 12 oz. sulphur, 6 oz.
camphor, and 4 oz. of turpentine: melt the whole together.

_Sec. XI. Of Powder Bags._

Powder bags are little sacks, that contain four pounds of powder.

They are of great use in besieged places. They are cast by the hand,
set fire wherever they fall, and very much intimidate troops making
an assault. They are made with good coarse cloth. Their width and
size are not determined. It is sufficient that they can be easily
thrown. The sides only are sewed up. In charging them, we begin by
tying one end with strong packthread. Then turn it inside out, so
that the ligature may be within, and fill it with powder, ramming
it down with a cartridge form, proportioned to the bag, until it is
full. Then put in the fuse, the large end inwards, and tie the bag
tight. Afterwards the outside is covered with tar, or pitch.

_Sec. XII. Of the Powder Barrel._

A powder barrel is a common barrel, filled with powder, to roll from
the top of a breach, or upon the head of a sap from the glacis. The
barrel contains from 100 to 200 pounds of powder, and is covered with
a cloth. A hole is made at each end, in which a fuse may be fixed, of
such a size, that the fire may be communicated to the powder, at the
moment when the barrel, rolled from the top of the breach, is met by
the troops mounting to the assault.

English writers state the diameter of powder barrels at 16 inches,
and 30 or 32 inches in length, and capable of holding 100 pounds
of powder. The quantity of powder put into them is 90 lbs; into
a half-barrel, 45 lbs; and into a quarter-barrel, used for rifle
powder, only 22-1/2 lbs. This proportion leaves a space for the
powder to separate when rolled, or otherwise it would always be in
lumps, and liable thereby to damage.

_Sec. XIII. Of the Burning or Illuminating Barrel._

This barrel differs from the thundering barrel, which we shall
describe in the following section, only in having no grenades; and
when it is placed upon a glacis, it lights up or discovers the works
of the besieger. It has a fuse in only one of its ends.

When shavings are boiled in the composition for links and fascines,
or of tourteaux, and arranged layer by layer, scattering, over each
stratum, some priming-powder, the combustion must be rapid, when the
barrel is set on fire.

Fire barrels, we may observe, are of different kinds. Some are
mounted on wheels, filled with composition, and intermixed with
loaded grenades, and their outsides full of sharp spikes. Some are
placed under ground, and have the effect of small mines; and others,
as the kind we have mentioned, are used to roll down a breach to
prevent the entrance of the enemy. The following composition has been
used for the same purpose.

_Composition for Fire-Barrels._

Grained powder, 30 lbs.
Pitch, 12 ----
Saltpetre, 6 ----
Tallow, 3 ----

_Sec. XIV. Of the Thundering Barrel._

This is employed for the same purpose as the preceding, or to light
up the works of the besieger at the foot of the glacis. It has the
same dimensions with the other, but has no cover. It is filled
with chips, (dipped into the composition of the tourteaux), which
are arranged in layers, putting, between each layer, meal-powder,
and grenades, furnished with their fuses, or with pieces of musket
barrels. The first and last layers are made with tow, boiled in the
carcass composition. The barrel being filled, it is then closed and
primed in the same way as the powder barrel, with a bomb fuse at
each end. Holes are made along the barrel to assist the combustion.
Grenades are employed in particular to prevent the approach of
persons to extinguish the flame.

The invention of bombs is said to be owing to Scotland, and to the
siege of St. Andrews. In the _Art of War_ (says the _Anthologia
Hibernica_, vol. iii, p. 174) printed at Venice, we are shown the
representation of a hogshead, coated with conical headed nails, in
which there is enclosed a barrel of gunpowder, suspended in the
centre by an iron tube, which communicates at both ends with the open
air. This engine, we are told by the author, killed 558 persons by
its explosion in the fosse.

_Sec. XV. Of the Petard._

The petard is used to break down the gates and barriers of small
towns, and even their walls, by hanging it against them, and setting
fire to the fuse. Its invention is ascribed to the French Huguenots
in 1579, who, by means of petards, took Cahors, in the same year. It
was invented, as others inform us, by the celebrated Coehorn.

The petard is a hollow piece of iron, either cast or wrought, of the
figure of a truncated cone, and usually eight inches high, and nine
and a half inches diameter at the base, the metal being five-sixths
of an inch thick at top, and half an inch at bottom. It is open at
the large end; and the small end, which is rounded, is pierced with
a hole, in which is placed a brass fuse, filled with composition, in
lieu of which, however, an ordinary bomb-fuse, or a quick-match may
be used. It is furnished with four trunnions, (one and a half inches
by one), to receive the iron staples, that are attached to an oaken
plank, eighteen inches square, and two and a half inches thick, and
reinforced below by two iron bands, in the form of a cross, nailed
and dove-tailed in. It has two iron handles to carry it by, and to
hook it to a screw, fixed in the gate intended to be broken. It is
filled with gunpowder.

When the petard is to be loaded, it is filled with powder to within
three inches of the bottom. Some folds of cartridge paper are then
put in, and a bed of tow well rammed. It is finished with a hot
cement made of one part of rosin, and two parts of ground brick,
or Spanish brown. A plate of iron four or five lines thick is set
into this, that fits the inside of the petard at that part. It is
furnished with three iron points, to be driven into the plank. A
petard, ready for use, weighs eighty-five pounds, and contains nine
pounds of powder.

_Dimensions of the Petard._

_Inches._

Exterior diameter of the opening. 9½
Exterior height. 8
{ At the height, ⅚
Thickness of the metal, { In the middle, ¾
{ At the bottom, ½

Trunnions, { Length, 1½
{ Height, 1

Fuses, { Length, 4-5/12
{ Diam. under the screw, 11/12
{ Diam. of the screw, 1⅓

Plank, { Length and width, 18
{ Thickness, 2½

According to Ruggeri, a petard is filled, after warming it, with
three fingers of powder, which is moistened with brandy, and then
compressed without crushing it. On this powder, a quick match is
placed, which is also compressed; after which, it is filled with
composition previously melted. The composition is as follows:

_Composition for Petards._

Pitch 4 parts.
Sulphur, 3 ----
Saltpetre, 1 ----
Antimony, 1 ----

After introducing one-half of this mixture, when melted, we put in
the iron plate, which rests on the composition, and then add the rest
of it, which finishes the operation.

_Sec. XVI. Of the Stink-Fire Lance._

This lance (_Lance à feu puant_ of the French) is prepared in the
same manner as stink-pots, and is principally used by miners. When a
miner or sapper has so far penetrated towards the enemy, as to hear
the voices of persons in any place contiguous to his own excavation,
he first of all bores a hole with his _probe_, then fires off several
pistols through the aperture, and lastly forces in a _lance à feu
puant_. He takes care to close up the hole on his side, to prevent
the smoke from returning towards himself. The explosion and fetid gas
and vapour, which issue from the lance, and remain on the side of the
enemy, infect the air so much, that it is impossible to approach the
quarter for three or four days. Sometimes, indeed, they have had such
instantaneous effect, that, in order to save their lives, miners,
who would persevere, have been dragged out in an apparent state of
suffocation.

The composition of ordinary fire-lance has been given. They are
sometimes used to set fire to fuses.

The fire-pot is a vessel made of clay, with two handles, in which
a grenade with powder is confined, and which is thrown against an
enemy, after the match has been lighted; but a stink-pot is a vessel,
filled with combustible and other matter, used in boarding ships, &c.

The suffocating pot is another contrivance, as its name expresses, to
produce suffocation; and, as the materials consist only of sulphur
and nitre, the gas which principally produces this effect is the
sulphurous acid.

_Composition for Suffocating Pots._

Sulphur, 6 parts.
Nitre, 5 ----

Connected with this subject, we may mention another composition, to
produce _smoke_, which is used either in pots, or balls. Hence, the
_smoke-pot_, and _smoke-balls_. The following is the composition.

_Composition for Smoke-Balls._

Grained-powder, 10 lbs.
Nitre, 2 --
Pitch, 4 --
Sea-coal, 3 --
Tallow, 1 --

The coal and pitch produce the smoke, and the gunpowder and nitre
promote the combustion, and, with the tallow render the product of
combustion more offensive.

_Sec. XVII. Of the Combustible Substances used in, and the Manner of
preparing, a Fire-Ship._

A fire-ship is a vessel, filled with combustible substances, and
fitted with grappling irons, to hook, and set fire to the enemy's
ships in battle, &c.

With respect to the preparation required, some knowledge may be had
by considering the following particulars. From the bulk-head at the
fore-castle, to a bulk-head to be raised behind the main chains, on
each side, and across the ship at the bulk-heads, is fixed, close to
the ship's sides, a double row of troughs, two feet distance from
each other, with cross troughs quite round, at about two and a half
feet distance, which are mortised into the others. The cross troughs
lead to the sides of the ship, to the barrels, and to the port-holes,
to give fire both to the barrels and to the chambers, to blow open
the ports; and the side troughs serve to communicate the fire all
along the ship, and the cross troughs.

The timbers, of which the troughs are made, are about five inches
square; the depth of the trough, half their thickness; and they are
supported by cross-pieces at every two or three yards, nailed to the
timbers of the ship, and to the wood-work, which encloses the fore
and mainmasts. The decks and troughs are all well payed with melted
rosin. On each side of the ship, six small port-holes are cut, from
fifteen to eighteen inches large, (the ports opening downwards), and
are close caulked up.

Against each port is fixed an iron chamber, which, at the time of
firing the ship, blows open the ports and lets out the fire. At
the main and fore chains, on each side, a wooden funnel is fixed
over a fire-barrel, and comes through a scuttle in the deck, up to
the shrouds to set them on fire. Both funnels and scuttles must be
stopped with plugs, and have sail-cloth or canvass nailed close
over them to prevent any accident happening that way by fire to the
combustibles below.

The port-holes, funnels, and scuttles, not only serve to give the
fire a free passage to the outside and upper parts of the ship and
her rigging, but also to allow the inward air (otherwise confined)
to expand itself, and push through those holes at the time of the
combustibles being on fire, and prevent the blowing up of the decks,
which otherwise must happen from the sudden and violent rarefaction
of the air.

In the bulkhead behind on each side, is cut a small hole, large
enough to receive a trough of the same size as the others, from
which, to each side of the ship, lies a leading trough, one end
coming through a sally port, cut through the ship's side, and the
other fixing into a communicating trough, that lies along the bulk
head, from one side of the ship to the other; and being laid with
quick-match, at the time of firing either of the leading troughs, it
communicates the fire, in an instant, to the contrary side of the
ship, and both sides burn together.

Having thus described this preparatory arrangement, we shall
consider, in the next place, the combustibles made use of in fitting
up a fire-ship.

_Fire-barrel._ The fire-barrels for this purpose are cylindrical,
on account of that shape answering better both for filling them
with reeds, and for stowing them between the troughs. Their inside
diameters are about 21 inches, and their length 33. The bottom
parts are first filled with double-dipt reeds, set on end, and
the remainder with fire-barrel composition, made of the following
substances.

_Composition for fire-barrels, for fire-ships._

Grained Powder 30 lbs.
Pitch 12 --
Saltpetre 6 --
Tallow 3 --

There are 5 holes of three-quarters of an inch in diameter, and
3 inches deep, made with a drift of that size, in the top of the
composition, while it is warm; one in the centre, and the other four
at equal distances, round the sides of the barrel.

When the composition is cold and hard, the barrel is primed by well
driving these holes, full of fuse composition, to within an inch
of the top; then fixing in each hole a strand of quick-match twice
doubled, and in the centre hole, two strands the whole length; all
which must be well driven with meal-powder. Then lay the quick-match
all within the barrel, and cover the top of it with a dipped curtain,
fastened on with a hoop to slip over the head, and nailed on.

_Bavins._ Bavins are made of birch, heath, or other sort of brush
wood, that is both tough and quickly fired. Their length is 2-1/2 to
3 feet. The bush ends are all laid one way, and the other ends, tied
with two bands each. They are dipped, and sprinkled with sulphur,
the same as reeds; with this difference, that the bush ends only are
dipped, and should be a little closed together by the hand as soon as
done, to keep them more compact, in order to produce a stronger fire,
and to preserve the branches from breaking in shifting and handling
them.

_Composition for Bavins._

Rosin 120 lbs.
Sulphur, coarse, or roll 90 --
Pitch 60 --
Tallow 6 --
Meal-powder 12 --

_Iron Chambers._ These are ten inches long, and 3.5 in diameter;
breeched against a piece of wood, fixed across the holes. When
loaded, they are almost filled with grained powder, with a wooden
tompion well driven into their muzzles. They are primed with a small
piece of quick-match, thrust through their vents into the powder,
with a part of it hanging out; and, when the ship is fired, they blow
open the ports, which either fall downwards, or are carried away,
and accordingly give vent to the fire out of the sides of the ship.

_Curtains._ Curtains are made of barras, about three-quarters of
a yard wide, and one yard in length. When they are dipped, two
men, with each a fork, must run the prongs through the corner of
the curtain at the same end. Then dip them into a large kettle of
composition, (which is the same as the composition for bavins,)
well melted; and, when well dipped and the curtain extended to its
full breadth, whip it between two sticks of about 5.5 feet long,
and 1.5 inches square, held close by two other men, to take off the
superfluous composition hanging to it. Then immediately sprinkle
sawdust on both sides, to prevent it from sticking, and the curtain
is finished.

_Reeds._ They are made up in small bundles of about 12 inches in
circumference, cut even at both ends, and tied with two bands each.
The longest sort are 4 feet, and the shortest 2.5, the only lengths
which are used. One part of them is single dipped, only at one end;
the rest are double dipped, that is, at both ends. In dipping, they
must be put about 7 or 8 inches deep into a copper kettle of melted
composition, of the same kind as that for bavins; and, when they have
drained a little over it, to carry off the superfluous composition,
sprinkle them, over a tanned hide, with pulverized sulphur, at some
distance from the copper. With respect to the stores, required for a
fire ship of 150 tons, the following complement is given: _viz._

No.
Fire barrels 8
Iron chambers 12
Priming composition barrels 3½
Quick-match barrels 1
Curtains dipped 30
Long reeds, single dipped 150
Short reeds { double dipped 75
{ single dipped 75
Bavins, single dipped 209

The quantity of composition, for preparing the stores of a fire ship
is as follows:

For 8 barrels; grained powder 960 pounds, pitch 480 pounds, tallow 80
pounds.

For 3 barrels of priming composition, saltpetre 175 lbs. sulphur 140
lbs. grained powder 350 lbs. rosin 21 lbs. oil-pots 11.

For curtains, bavins, and reeds, and sulphur to _salt_ them, as
artificers call it; sulphur 240 lbs. pitch 350 lbs. rosin 175 lbs.
tallow 50 lbs. tar 25 lbs.

Total weight of the composition 3017 pounds, equal to 26 cwt. 3 qr.
21 lbs.

The composition, required for the rods and barrels, is one-fifth of
the whole of the last article, which is equal to 160 lbs. making in
the whole, 3177 lbs. or 28 cwt. 1 qr. 13 lbs.

Adye (_Bombardier and Pocket Gunner_) has given two general formulæ
for the composition, used in fire-ships, which we will here insert.

_Composition for dipping reeds, bavins, and curtains._

Rosin, 120 lbs
Coarse sulphur, 90 --
Pitch, 60 --
Tallow, 6 or 8
Mealed powder, 12 --

_Composition for priming._

Pulverized saltpetre, 22 lbs. 8 oz.
Rosin, 2 -- 11 --
Sulphur, 18 --
Meal-powder, 45 --
Linseed oil, 1 pint.

The composition put in cases, to set fire to fascine batteries, is
sometimes used in fire-ships, _viz._

_Composition for setting fire to Fascine Batteries._

Meal-powder, 1 lb. 4 oz.
Saltpetre, 6 --
Sulphur, 1 -- 8 oz.

There is also another composition, which might be used advantageously
for the same purpose, and which is employed for hoops, fire-arrows,
and lances, namely:

_Composition for Hoops, Fire-Arrows, &c._

Meal-powder, 1 lb.
Saltpetre, 3 --
Sulphur, 8 oz.
Linseed oil, 8 --

The composition of kitt, used for the last covering of carcasses,
may also be employed. It must be applied when very thin and hot.

_Composition of Kitt._

Rosin, 9 lbs.
Bees' wax, 6 --
Pitch, 6 --
Tallow, 1 --

_Sec. XVIII. On Infernal Machines._

The _Machines Infernales_ of the French, which have excited so much
attention in Europe, we deem of sufficient importance to describe.

This invention is by no means new, although it has been attributed
to the French. It appears that Fredric Jambelli, an Italian
engineer, was the first that used them, when Alexander, of Parma,
besieged Antwerp. The Prince of Orange likewise had recourse to the
destructive effects of an infernal machine, in order to bombard
Havre-de-Grace, and to set it on fire. The Dutch and English, in
conjunction, attempted to destroy St. Malo by the same means. The
first instance, however, upon record, in which the French made use
of this machine, was when Louis XIV ordered a vessel, carrying an
enormous shell, full of every kind of combustible matter, to be
despatched to Algiers, for the purpose of demolishing its harbour.
This, it is supposed, suggested the use of fire-ships, which have
frequently been used against maritime places.

The author of the _Œuvres Militaires_, tom. xxii, p. 222, speaking
of the infernal machine, observes, that, if he were to be in a
situation, which required the use of so dreadful an explosion,
especially to destroy a bridge, he would prefer having the machine
made simply with different strong pieces of wood, joined together, so
as to be in the shape of an egg, or of a cone reversed.

The whole must then be made compact with cords twisted round. This
method, in his opinion, is not only the best, but can be executed in
the most easy and expeditious manner. He further adds, that, in order
to burn or blow up wooden bridges, and even to destroy such as are
constructed upon arches, several sorts of barges or boats might be
used, which should be filled with fire-works, bombs, petards, &c. It
would, likewise, be easy to construct these machines upon floating
rafters, carrying several thousand pounds weight of gunpowder, which
might be confined within strong pieces of wood, put together in the
manner already described.

These machines should be piled one above another, and long iron
bars must be thrown across the floats, or be fixed like masts; so
that, when the whole of the combustible material is beneath the
centre of the bridge, the rafters may be stopped. Great care must be
taken to dispose the matches in such a manner, that no fire may be
communicated to the gunpowder before the machine reaches the exact
spot, which is to be destroyed.

In 1804, an infernal machine was used at Boulogne, which is described
as follows:

This machine appears to be as simple in its construction, as it is
calculated to be effectual in its operations. It is composed of 2
stout planks, 17 feet long, which form its sides, and are distant
from each other about 7 feet.

These planks are connected by transverse timbers, screwed to the
planks; so as to keep the whole firm and compact, and to prevent
the danger of their being separated at sea. Of these transverse
timbers, two are at the fore extremity, and three behind. This may
be called, the frame or hull of the machine; the remainder of the
work, being either for the stowage of the combustible matter, or
for the accommodation of the seamen, who row the machine. Along the
transverse timbers, at both extremities, are laid parallel to the
sides, five longitudinal bars of nearly the same strength as the
transverse timbers, which form a kind of grate, on which the coffers,
containing the combustible matter, are placed. The grate behind
is double the size of the one before, on the principle of giving
facility to the motion of the whole, by making the machine lighter at
the head. In the centre, between the planks forming the sides, from
the inner extremity of the grate behind, to the outer extremity of
the grate before, there is fixed a plank, somewhat broader than the
side planks, which is well secured to them by three stout transverse
timbers, which pass under the centre plank, to prevent its giving way
to pressure.

In this plank, two triangular apertures are cut for men who row,
to dispose of the lower extremities, whilst they ply the machine.
Their seats, however, are so contrived, that each man's pressure
is directly over that part of the plank, which is supported by the
transverse timbers. The seats lie nearer to the head than to the hind
part of the machine; perhaps to be some counterpoise for the greater
weight of the combustible matter behind. Near each seat are fastened
by rings to the sides, two oars, one on each side, and each man plies
a pair. When the machine is worked to its destination, the men set
the combustibles in a train for explosion, and abandon their posts.

The whole is so regulated, as to weight of materials, that the
machine floats, or, more probably, moves under the surface of the
water; so that little more than the heads of the men are seen. This
secures the men and the machine from the fire of the enemy; and as
the oars must be constantly plied under water, there is less danger
of their being discovered by their noise, as they approach.

Infernal machines have also been made, to be used on land. Such is
the machine we are told, which was intended for the destruction
of Bonaparte. They may be made to explode at a given time, by
clock-work, or by a match, calculated to burn a certain time!

_Sec. XIX. Of the Catamarin._

The catamarin, properly so called, is a floating raft, originally
used in China, and among the Portuguese as a fishing-boat. The Indian
catamarin consists of two logs of wood, upon which the natives float,
and go through the heaviest surf.

The military or naval catamarin is a different thing. It is properly
a case, filled with combustibles, and contrived to remain so low
in the water as to be almost imperceptible. This, being towed to
the building, or ship, against which the attack is to be directed,
is left to explode, by means of machinery within itself, when its
operation is sometimes very destructive.

English writers acknowledge, that the catamarin, submitted by the
late Mr. Pitt to the English government, and which cost in its
construction a considerable sum, was originally invented by our
countryman, the late Mr. Fulton, of whose invention we will speak
hereafter.

Some observations on a boat, named, by the French, _Chelingues_,
and the Indian catamarin, may be seen in the _Dictionnaire de
l'Industrie_, article _Bateau_.

Several diving machines have been invented in France and elsewhere.
M. Castera (_Archives des Découvertes_, iii, p. 185) describes a
_plunging boat_, which resembles in figure a cone. It is furnished
with a reservoir, calculated to hold water, and may be filled or
emptied by means of pumps. By means of glasses and copper handles,
the navigator is enabled to see and to take hold of objects. It is
also furnished with tubes for the transmission of the air necessary
for respiration, that communicate from the interior of the vessel
with the atmosphere; and a double bellows, designed as well for
receiving, as expelling air. Besides oars or paddles, necessary
to move it under water, there is a contrivance for detaching the
boat from the reservoir, either wholly or in part, according to
circumstances.

M. Castera, in a memoir on _sub-marine navigation_, has noticed
several applications of the plunging boat, which may be seen in the
_Bulletin de la Société d'Encouragement_, No. 71. In No. 61, of the
same work, is the first notice of Castera's invention, an extract
of which may be seen in the _Archives des Découvertes_, ii. p. 121.
A description of Lutgendorf's boat may be seen in the _Magazin der
Erfindungen_, No. 46.

_Sec. XX. Of the American Turtle._

It is well known that the diving-bell, and similar contrivances, have
been used for naval purposes, in connection with naval warfare.

Divers, or those who made it a business, by long habit and
experience, to remain under water, and go to a great depth, were
often employed in war to destroy the works and ships of the enemy.
When Alexander was besieging Tyre, divers swam off from the city,
under water, to a great distance, and, with long hooks, tore to
pieces the mole, with which the besiegers were endeavouring to block
up the harbour. The invention of the diving-bell, the _campana
urinatoria_ of some, is generally assigned to the sixteenth century;
but it is evident, from the writings of Aristotle and others, that,
in his time, divers used a kind of kettle to enable them to continue
longer under water.

At the pearl fisheries, in the Bay of Condalzchy, in Ceylon, divers
usually remain under water two minutes. There are some who can stay
five minutes; and a diver from Anjano, engaged in this fishery in
1797, was able to remain six minutes under water. But their efforts
are so great, that, when they come up, blood frequently issues
from their mouths, ears, and nostrils. Notwithstanding this, they
frequently dive from forty to fifty times a day, and bring up in a
bag-net a hundred oysters each time.

It may be proper to observe, that the subject of sub-marine
navigation was largely descanted upon by Mersennus, (_Tractatus de
Magnetis Proprietatibus_), and by Bishop Wilkins (_Mathematical
Magic_, 1648), who, by the way, is rather visionary. The conveniences
and advantages he enumerates, are: 1. 'Privacy, as a man may thus
go to any part of the world invisibly, without being discovered
or prevented. 2. Safety, from the uncertainty of tides and
tempests, &c. 3. It may be used to blow up, or undermine a navy:
4. Or to relieve a blockaded place, &c. But, with regard to the
use of sub-marine vessels in war, Mr. David Bushnel, of Saybrook,
Connecticut, appears to be entitled to the credit of the invention.
His account of it may be seen in the _Transactions of the American
Philosophical Society_. The intended object of this vessel was to
destroy shipping, by the explosion of a magazine of gunpowder.

In Silliman's _Journal of Science and Arts_, vol. II, p. 94, is a
communication by Mr. Griswold, on the subject of Bushnel's machine,
with an account of the first attempt with it, in August, 1776, by
Ezra Lee, a sergeant in the American army, to destroy some of the
British ships then lying at New York. Mr. Griswold remarks, that,
considering the invention of Mr. Bushnel as the first of its kind,
it will be pronounced to be remarkably complete throughout in its
construction, and that such an invention furnishes evidence of those
resources and creative powers, which must rank him as a mechanical
genius of the first order.

He has given a description of it; but the outline which we give is
taken from _Nicholson's Journal_, quarto, iv, p. 229.

It is a decked boat, to go underwater: and several persons have gone
under water many leagues. The difficulty is, to provide the persons
in the boat with fresh air for respiration; and this is contrived,
by having a reservoir of air, of suitable dimensions to the size of
the boat, and the number of persons in it. By means of a condensing
pump, the air, in this reservoir, is condensed about 400 times;
and by a spring, the air is let out at intervals, as circumstances
require, the carbonic acid produced by respiration being absorbed by
quicklime. Within this boat are flaps, like those of a rundle, to
move the boat, two rudders, one vertical, the other horizontal, and
a pump to empty the hold, or air reservoir. The person within, can,
at pleasure, come to the top of the water. The different experiments
made by Mr. Bushnel may be seen in the _Transactions_ referred to, or
in _Nicholson's Journal_, quarto, iv, 229.

During the late war, Mr. Fulton, Mr. Mix, and some others, made
various experiments with submarine machines; and during the
revolution, the incendiary kegs, well known by the name of the
"_battle of the kegs_," excited no small attention, and, had it
not been for some unforeseen circumstance, they would, in all
probability, have produced the effect for which they were intended.

Of Bushnel's vessel, we may observe, that, in the fore part of the
brim of the crown, as it is called, was a socket, and an iron tube
passing through the socket. The tube stood upright, and could slide
up and down in the socket, six inches. At the top of the tube was a
wood screw, fixed by means of a rod, which passed through the tube,
and screwed the wood screw fast upon the top of the tube. By pushing
the wood screw up against the bottom of a ship, and turning it at the
same time, it would enter the planks. When the wood screw was firmly
fixed, it could be cast off by unscrewing the rod, which fixed it
upon the top of the tube.

Behind the submarine vessel, was a place, above the rudder, for
carrying a large powder magazine. This was made of two pieces of oak
timber, sufficiently large, when hollowed out, to contain 150 lbs.
of powder, (130 lbs. according to Griswold,) with the apparatus used
in firing it, and was secured in its place by a screw, turned by the
operator. A strong piece of rope extended from the magazine to the
wood screw above mentioned, and was fastened to both. When the wood
screw was fixed, and to be cast off from its tube, the magazine was
to be cast off likewise by unscrewing it, leaving it hanging to the
wood screw; it was lighter than the water, that it might rise up
against the object, and apply itself when fastened.

Mr. Griswold remarks, that the most difficult point of all to be
gained, was to fasten this magazine to the bottom of a ship.

Within the magazine, was a machine, constructed to run any proposed
length of time under twelve hours. When it had run out its time,
it unpinioned a strong lock resembling a gun-lock, which gave fire
to the powder. This apparatus was so pinioned, that it could not
possibly move, till, by casting off the magazine from the vessel, it
was set in motion.

This skilful operator could swim so low on the surface of the
water, as to approach very near a ship in the night without fear
of discovery, and might, if he chose, approach the stem or stern
above water, with very little danger. He could sink very quickly,
keep at any depth he pleased, and row a great distance in any
direction he desired, without coming to the surface; and, when he
rose to the surface, he could soon obtain a fresh supply of air;
when, if necessary, he might descend again and pursue his course.
The projector found some time and attention to be requisite for the
gradual instruction of this operator, and, after various attempts,
he found one, on whom he thought he could depend. He sent this man
from New York to a 50 gun ship, lying not far from Governor's island.
He went under the ship, and attempted to fix the wood screw in her
bottom, but struck, as he supposed, a bar of iron, which passes from
the rudder's hinge, and is spiked under the ship's quarter. Had he
removed a few inches, which he might have done without rowing, the
projector has no doubt but he might have found wood, where he might
have fixed the screw; or if the ship were sheathed with copper, he
might easily have pierced it. But, not being well skilled in the
management of the vessel, in attempting to row to another place, he
lost the ship. After seeking her in vain some time, he rowed to some
distance, and rose to the surface of the water, but found day light
had advanced so far, that he durst not renew the attempt. He says,
he could easily have fastened the magazine under the stern of the
ship above the water, as he rowed up to the stern, and touched it
before he descended. Had he fixed it there, the explosion of 150 lbs
of gunpowder (the quantity contained in the magazine) must have been
fatal to the ship. In his return from the ship to New York, he passed
near Governor's island, and thought he was discovered by the enemy
on the island. Being in haste to avoid the danger he feared, he cast
off the magazine, as he imagined it retarded him in the swell, which
was very considerable. After the magazine had been cast off an hour,
the time the internal apparatus was set to run, it blew up with great
violence.

Mr. Griswold gives an account of an attempt to destroy a ship of
war; and having received his information from Mr. Lee, one of the
adventurers, we have thought proper to introduce it from that source.

"It was in the month of August, 1776, when Admiral Howe lay with a
formidable British fleet in New York bay, a little above the narrows,
and a numerous British force upon Staten Island, commanded by General
Howe, threatened annihilation to the troops under Washington, that
Mr. Bushnel requested General Parsons, of the American army, to
furnish him with two or three men to learn the navigation of his new
machine, with the view of destroying some of the enemy's shipping.

"General Parsons immediately sent for Lee, then a sergeant, and two
others, who had offered their services to go on board a fire ship;
and on Bushnel's request being made known to them, they enlisted
themselves under him for this novel piece of service. The party
went up into Long Island sound with the machine, and made various
experiments with it in the different harbours along shore; and
after having become pretty thoroughly acquainted with the mode of
navigating it, they returned through the sound; but, during their
absence, the enemy had got possession of Long Island and Governor's
Island. They, therefore, had the machine conveyed by land across from
New Rochelle to the Hudson river, and afterwards arrived with it at
New York.

"The British fleet now lay to the north of Staten Island, with a
large number of transports, and were the objects against which this
new mode of warfare was destined to act. The first serene night
was fixed upon for the execution of this perilous enterprize, and
sergeant Lee was to be the engineer. After a lapse of a few days, a
favourable night arrived, and, at 11 o'clock, a party embarked in
two or three whale boats, with Bushnel's machine in tow. They rowed
down as near the fleet as they dared, when sergeant Lee entered the
machine, was cast off, and the boats returned.

"Lee now found the ebb tide rather too strong, and before he was
aware, had drifted him down past the men of war. He, however,
immediately _got the machine about_, and by hard labour at the crank
for the space of five glasses by the ship's bells, two and a half
hours, he arrived under the stern of one of the ships at about slack
water. Day had now dawned, and by the light of the moon he could
see the people on board, and hear their conversation. This was the
moment for diving: he accordingly closed up over head, let in water,
and descended under the ship's bottom. He now applied the screw, and
did all in his power to make it enter; but owing probably in part to
the ship's copper, and the want of an adequate pressure, to enable
the screw to get a hold on the bottom, his attempts all failed.
At each essay, the machine rebounded from the ship's bottom, not
having sufficient power to resist the impulse thus given to it. He
next paddled along to a different part of her bottom, but, in this
manœuvre, he made a deviation, and instantly rose to the water's
surface on the east side of the ship, exposed to the increasing
light of the morning, and in imminent hazard of being discovered.
He immediately made another descent, with a view of making one more
trial; but the fast approach of day, which would expose him to the
enemy's boats, and render his escape difficult, if not impossible,
deterred him; and he concluded the best generalship would be, to
commence an immediate retreat. He now had before him a distance of
more than four miles to traverse, but the tide was favourable. At
Governor's island, great danger awaited him; for his compass having
got out of order, he was under the necessity of looking out from the
top of the machine very frequently, to ascertain its course, and at
first made a very irregular zigzag track. The soldiers at Governor's
island espied the machine, and curiosity drew several hundreds upon
the parapet to watch its motions. At last a party came down to the
beach, shoved off a barge, and rowed towards it. At that moment,
sergeant Lee thought he saw his certain destruction, and as the last
act of defence, let go the magazine, expecting they would seize that
likewise, and thus all would be blown to atoms together. Providence,
however, otherwise directed it: the enemy, after approaching within
50 or 60 yards of the machine, and seeing the magazine detached,
began to suspect a _yankee trick_, took alarm, and returned to the
island. Approaching the city, he soon made a signal; the boats came
to him, and brought him safe and sound to the shore. The magazine,
in the mean time, had drifted past Governor's island into the East
river, where it exploded with tremendous violence, throwing large
columns of water, and pieces of wood that composed it, high into the
air. General Putnam, with many other officers, stood on the shore,
spectators of this explosion.

"In a few days, the American army evacuated New York, and the machine
was taken up the North river. Another attempt was afterwards made by
Lee, upon a frigate that lay opposite Bloomingsdale. His object now
was to fasten the magazine to the stern of the ship, close at the
water's edge. But while attempting this, the watch discovered him,
raised an alarm, and compelled him to abandon his enterprize. He then
endeavoured to get under the frigate's bottom; but in this he failed,
having descended too deep. This terminated his experiments."

With regard to diving bells, several machines, for the purpose of
descending under water, &c. have been invented. Some experiments
have been made by the French with similar contrivances, without any
adequate result; and the difficulty of carrying them into execution,
in real practice, will prevent their introduction.

Dr. _Caustic_, (_Terrible Tractoration_, p. 65), in a note, in
reference to Bushnel's invention, observes, that if you consult the
Transactions of the American Philosophical Society, "you will see
what Mr. D. Bushnel, of Connecticut, has done, and had like to have
done, by virtue of submarine explosions. You will find, that several
English ships have been put in jeopardy, and one schooner actually
blown up and demolished by Mr. Bushnel's submarine explosions."[33]

_Sec. XXI. Of the Torpedo._

The late Mr. Fulton applied himself to the improvement of the
_Turtle_ during the late war, and brought it to such perfection,
that if it came in contact with a ship's bottom, it would inevitably
blow up the vessel. From the account we have given of the turtle, we
may readily imagine the construction of the torpedo. These were of
several kinds; some (or rather the magazine attached to them,) were
designed to be screwed under the bottom, and others to explode by
coming in contact with the vessel, or any resisting body. The time of
explosion was so determined, by clock-work machinery, in the manner
of Bushnel's contrivance that it would invariably explode at the
minute or second required.

Mr. Fulton wrote a number of essays on this torpedo, and other
contrivances for annoying the enemy, such as the harpoon, &c. The
torpedo, at which the British ships, stationed on our coast, were
so much alarmed, is in fact a powerful weapon of destruction. It
is to be observed, that the magazine, accompanying the _bell_,
in some instances, was detached; so that the latter was removed
out of danger, when the former was fixed to the ship's bottom. In
order to prevent the torpedo from floating against the sides of a
vessel, the precaution of having netting spread at some considerable
distance round the vessel, and of keeping up a constant guard of
boats, which were rowed round the ship both day and night, was used.
Not having the writings of Mr. Fulton before us, we can give no
precise description of his improvements. They are described to be an
apparatus, of which the principal piece is a copper box, and prepared
with an interior spring, which sets fire to the powder; at the same
time that the whole is enclosed in a covering of cork, or some other
light wood, to make the torpedo float under the surface of the water.

It will be sufficient to remark, that _they_ have produced the
_effect_ of causing a constant, and, in our opinion, painful anxiety
to the British. Of this we have abundant proof. We may add, however,
the result of some of the experiments, by which it will appear, that
they are eminently calculated, like the infernal machine, to produce
death and destruction.

In consequence of some essays, published by Mr. Fulton, on the
practicability of destroying ships by torpedoes, several persons
turned their attention to this subject; among whom was a Mr. Mix
of the navy. Mr. Mix's intention was to destroy the ship of war
Plantagenet, of 74 guns, lying in Lynnhaven bay. Having made a
torpedo, Mr. Mix, accompanied by two gentlemen, one of whom was a
midshipman, proceeded in a boat, on the night of the 24th of July,
1813, and, having reached within 100 yards of the ship, dropped the
torpedo. It was swept along by the side, but exploded a few seconds
before it would have come in contact with the vessel. It produced,
however, great consternation and confusion on board the vessel,
and induced several of the crew to take to their boats. The ship
was greatly agitated, and some damage done by the violent motion
of the water. The noise, occasioned by the explosion, was loud and
tremendous; and the appearance of the water, thrown up in a column
of thirty or forty feet high, awfully sublime. It has not been
ascertained, that any lives were lost.

The case of a Mr. Penny, of Easthampton, Long Island, is connected
with the subject of torpedoes. He was carried on board the Ramilies,
and put in irons; because his name had been entered on the books of
one of the frigates, as having been "_employed in a boat, contrived
for the purpose, under the command of Thomas Welling, prepared with a
torpedo, to destroy this_ (Capt. Hardy's) _ship_."

The affair of Stonington, also, shows, that the British were
determined to punish the inhabitants for having, as captain Hardy
expresses it, prepared torpedoes; and the captain stated, in his
reply to the deputation from the town, that the bombardment should
cease, in case the inhabitants would engage that no _torpedoes_
should be fitted out by them. No torpedoes, however, were fitted out
at Stonington.[34]

Mr. Fulton made a number of experiments with the torpedo, in the
harbour of New York; and one vessel was completely cut in two. These
experiments were very satisfactory to all who witnessed them.

The greatest difficulty he experienced was in giving them a proper
direction, so as to hit the vessel intended to be destroyed. This he
acknowledged to a friend, professor Eaton, of Troy, who informed us
of the fact. He entertained no doubt whatever of the effect of the
torpedo, when once brought in contact with a vessel.

At Havre, in France, Mr. Fulton constructed a sub-marine boat,
sufficient to contain several men, and air for eight hours, and
strong enough to bear submersion to the depth of one hundred feet, if
necessary. In this boat, he remained an hour under water, made half a
league of way in that time, with his boat horizontally situated, and
at various depths, where he found that the compass traversed exactly,
as on the surface. To the boat he attached a machine, by means of
which he blew up a lighter in Brest Harbour.

While in France, in the time of the Republic, Mr. F. directed his
attention to this subject. His _Bateau-poisson_, described in the
_Dictionnaire de l'Industrie_, vol. i, p. 265, is of the same
character. A number of experiments performed with it are given.

_Sec. XXII. Of the Marine Incendiary Kegs, &c._

We purpose to notice, under this head, two contrivances, which have
been used, the one in the revolution, and the other, during the late
war with Great Britain.

The piece of poetry, called the _Battle of the Kegs_, written by
the late Francis Hopkinson, Esq. of Philadelphia, narrating the
incendiary kegs, is founded on this contrivance.

For the purpose of destroying the shipping at Philadelphia, which
was then in possession of the British, some forty or more kegs were
fitted up at Burlington, N. J. or in its neighbourhood, containing
a quantity of gunpowder. These kegs were connected in such a manner,
that, while they formed one float, when one exploded, the whole
would go off. This arrangement was also made with another, if our
information is correct, which consisted in a trigger connected with
a gun-lock, (one or more kegs having the same); so that, when the
triggers went off, by the casks coming against any thing, in floating
down the tide, the whole would explode at the same time. There is one
of the original kegs in the magazine of Fort Mifflin. We apprehend,
however, that the contrivance was more like that of clock-work, set
to a given time, like the torpedo of Fulton; but of this we have
no certain account. These kegs were towed down the river, within a
mile or two of the city, and were seen about sunrise opposite to it.
They did no execution; but, if they had been taken to a given spot,
instead of being left to the direction of the running current, and
then properly adjusted, no doubt the effect would have been as the
contriver calculated. It excited, however, no small sensation at the
time.

Of the other contrivance, we have the following account: A Mr.
Scudder (_History of the late War, &c._ p. 187) formed a design of
destroying the British ship Ramilies, of 74 guns, off New London.
For this purpose, 10 kegs of powder were put into a strong cask,
with a quantity of sulphur mixed into it. At the head of the cask
were, fixed two gun-locks, with cords fastened to the triggers, and
to the under side of the barrels in the hatchway; so that it was
impossible to hoist the barrels, without springing the locks each
side of the powder. On the top were placed a quantity of turpentine
and spirits of turpentine, which in all probability were sufficient
to destroy any vessel that ever floated. These kegs were put on
board the smack Eagle, which sailed from New York on the 15th of
June, for New London; but which the crew abandoned, on being pursued
by the boats of the enemy. It was expected, that the vessel would
be brought alongside the Ramilies, and, by exploding, destroy that
ship. The wind dying away, and the tide being against them, she could
not, very fortunately for the enemy, be brought alongside. When the
Eagle exploded, there were four boats alongside, and a great many
men on board of her. After the explosion, there was not a vestige
of the boats to be seen. A body of fire rose to a vast height, and
then burst like a rocket. Every man, near or about her, was probably
lost, as the boats sent from the Ramilies were seen to return without
picking up anything.

In relation to similar enterprizes, what could have been a more
daring and hazardous enterprize, than that of lieutenants Wadsworth,
Summers, &c. who, by a previous agreement, determined, if they were
likely to be captured by the Turks, to blow themselves up in the
fire-ship, which they had prepared to destroy the enemy's shipping,
in the harbour of Tripoli? Their fate is too well known, lamentable
as it is!

The marquis of Worcester, in his _Century of Inventions_, inventions
nine and ten, speaks of certain contrivances for the destruction of
vessels, which seem to have been of the kind mentioned: _viz._ "An
engine, portable in one's pocket, which may be carried and fastened
on the inside of the greatest ship, _tanquam aliud agens_; and, at an
appointed minute, though a week after, either of a day or night, it
shall irrecoverably sink that ship;" and "a way from a mile off, to
drive and fasten a like engine to any ship, so as it may punctually
work the same effect, either for time or execution."

_Sec. XXIII. Of Sea Lights._

The _fanaux de mer_, or sea lights, are so called, from the
particular application of this fire.

It is sometimes required at sea to throw light upon the water, and
around the vessel, in order to perceive the approach of an enemy.
This is effected by the composition for sea lights.

A tube must be formed of not less than three inches in diameter, and
eleven inches in length. A shield is then adapted, of four times the
exterior diameter of the tube or case, which shield is to be made of
wood, and attached at about the distance of one-fourth of the length
of the tube, and near the end of the orifice.

The case or tube is then charged with the following composition:

_Composition for Sea Lights._

Saltpetre, 16 parts.
Sulphur, 8 ----
Meal-powder, 3 ----
Antimony, 3 ----

The tube, which may be made of iron, pasteboard, or wood, by boring
it out, after being charged, is primed in the usual manner, inserting
in the end, at the same time, a piece of quick-match. When dried, it
is wrapped in paper for better preservation.

_Sec. XXIV. Of Signal and War-Rockets._

Rockets, we have said, are cylindrical cases, formed generally
of pasteboard, and filled with a peculiar composition, made of
meal-powder, saltpetre, sulphur, and charcoal; or without powder,
and sometimes with the addition of pulverized cast iron. In some, as
the Congreve rocket, iron cases are substituted for those of paper.
The outer diameter is usually from one and a half to two inches,
the length of the charge five diameters, and the interior diameter
two-thirds as much as the exterior. The tools necessary are, a rod
or former of wood, to mould the case upon; an artificer's tool to
roll the paper close; a conical spit or piercer, by means of which
the rocket when loaded has a hollow through the middle, which piercer
should be four and two-thirds times as long as the outer diameter of
the rocket, one-third of this diameter at the base, and one-sixth at
the small end; three rods for loading, having a conical aperture to
receive the piercer, and one massive; and a ladle or measure, whose
diameter is equal to that of the inside of the rocket, and its length
three times as much. The construction of the cartouch case, or paper
cylinder, consists in using pasteboard of three or more thicknesses,
which is rolled on the former, until the case becomes sufficiently
thick. The choaking of the cylinder is performed by means of a cord,
of three lines in diameter, one end of which is firmly fixed into
a wall, and the other tied to a stick, against which the artificer
who bestrides the cord rests. The rocket is loaded or charged, by
introducing at a time, a ladle full of composition, first fixing the
case over the piercer, and using the appropriate rammer and mallet,
in the manner stated, &c.[35]

Signal rockets are sometimes _trimmed_ with serpents, stars, and
petards. The serpents are made of cases in the manner already
mentioned; _viz._ by rolling playing cards in the direction of their
length, upon a former, three lines in diameter, and covered with
three coats of paper, the last of which is pasted. The cases are
choaked at one end, and in the niche is placed a strand of tow, and
a priming of meal-powder, moistened with brandy. They are loaded,
by means of a rod, three-fourths full of the composition, and again
choaked at half their height. The remainder is filled up with powder,
to make a report. If a serpent with stars is to be made, only half
the case is filled with the serpent-composition, and the rest with
that for stars. Serpents are placed upright in the pot, the priming
down.

_Composition for Serpents, for trimming Signal Rockets._

Meal-powder, 16 parts.
Saltpetre, 3 ----
Sulphur, 2 ----
Charcoal, ½ ----

The star composition is the same as before given.[36] It is mixed and
made into balls or cubes, in the same manner. The petards or crackers
are small cubes of paper, filled with grained gunpowder. They are
wrapped with two layers of good thread, which is drawn tight in every
direction. They are dipped in tar to give them more consistence, and
pierced and primed with quick match. We have already given the theory
of the flight of rockets in the first part of this work; and also the
opinions of Mariotte and Dr. Desaguliers. On this head, therefore,
further observation seems unnecessary We have said, however, that it
is necessary, for giving the rocket a sufficient degree of motion,
that the powder within the rocket be bored with a tapering cavity
from the choke, and at the choke this cavity must be as wide as the
choke itself, and at the further end, not more than half that width.
The length of this bore must be but one inner diameter of the rocket,
short of the whole height to which the rocket is rammed. The use of
this bore, it is to be observed, is to increase the surface, that
takes fire at once; that a greater body of fire may issue out of the
mouth of the rocket. From the vehemence with which the fire issues
out, the rocket receives its motion. We have seen, that rockets are
used in all fire-works that have motion; for cases charged give
motion to wheels of various kinds, and act on the same principle.
Such works as are thrown into the air after the manner of bombs, are,
however, an exception.

The rocket-stick is a necessary appendage. When very heavy, to
prevent mischief by their fall, they now bore the sticks, and fill
them with powder, that they may shiver in the air before they fall.

That the stick keeps the rocket perpendicular is obvious. If the
rocket should begin to tumble, moving round a point in the choke,
as being the common centre of gravity of rocket and stick, there
would be so much friction against the air, by the stick between the
centre and the point, and the point would beat against the air with
so much velocity, that the reaction of the medium would restore it
to its perpendicularity. When the composition is burnt out, and the
impulse upwards has ceased, the common centre of gravity is brought
lower towards the middle of the stick. Hence the velocity of the
point of the stick is decreased, and that of the point of the rocket
increased; so that the whole will tumble down, with the rocket end
foremost. During the combustion of the rocket, the common centre of
gravity is shifting and getting downwards, and faster and lower as
the stick is lighter.

In the _Philosophical Transactions_, (vol. xlvi, p. 578) and Robins's
_Mathematical Tracts_, (vol. i, p. 317, &c.) are sundry experiments,
and observations concerning the flight of rockets; and as these
experiments appertain more to military purposes, the following
extracts may, on that account, be useful.

Mr. Robins, considering the great use that may be made of rockets,
in determining the position of distant places, and in giving signals
for naval and military purposes, procured some, with a view of
ascertaining the height to which they rise, and the distance at
which they may be seen. The greatest part of them did not rise to
above four hundred yards; one to about five hundred; and one to six
hundred yards nearly. The greatest distance at which these were
observed, was from thirty-five to thirty-eight miles. Others were
fired at a different time, one of which rose to six hundred and
ninety yards; and it was observed, that the largest, which were
about two and a half inches in diameter, rose the highest. In some
subsequent experiments, conducted by Mr. Da Costa, Mr. Banks, &c. it
was found, that, of two rockets, of about three and a half inches
in diameter, one rose to about eight hundred and thirty-three, and
the other to 915 yards. In another trial, a rocket of four inches
in diameter rose to one thousand one hundred and ninety yards. In
other experiments, a rocket of one and a half inches rose to seven
hundred and forty-three yards; one of two inches to six hundred
and fifty nine; one of two and a half inches to eight hundred and
eighty; another of the same size to one thousand and seventy-one;
one of three inches to one thousand two hundred and fifty-four; one
of three and a half inches to one thousand one hundred and nine; and
one of four inches rose to seven hundred yards, and, turning, fell
to the ground before it went out. Besides these, there was one of
the rockets of "twenty-four inches in diameter,"[37] which rose to
seven hundred and eighty four yards, and another of the same size, to
eight hundred and thirty-three yards. From these experiments, it is
inferred, that rockets from two and a half to three and a half inches
in diameter, are sufficient to answer all the purposes for which they
are intended; and they may be made to rise to a height, and to afford
a light capable of being seen to considerably greater distances than
those just mentioned.

Before we mention the war-rockets of Congreve, it may not be improper
to speak of the Indian rockets, which are used by the native troops
of India, and which were employed against the British, with great
effect, during the seige of Seringapatam in 1799. These rockets
are made of iron, and are lashed to a bamboo cane. The weight is
seldom more than two pounds, or less than one. The _fougette_, or
Indian rocket, resembles in shape a sky-rocket, _whose flight is
gradually brought to run along a horizontal direction_. By throwing
several fougettes into parks of artillery, and upon caissons, &c.
considerable damage might be occasioned from the fire, which would
inevitably be communicated to some part. A fougette forces itself
immediately forward, cuts as it penetrates, by the formation of its
sides, which are filled with small spikes, becomes combustible, and
on fire at all its points, and possesses within itself a thousand
different means, by which it can adhere to whatever object it is
destined to set on fire or destroy. A French writer even asserts,
that this weapon would be more effectual, because it might be more
variously applied, to defend the mouth of a harbour against an
enemy's shipping, than red-hot balls can ever prove; and we are also
told, that, by means of their natural velocity, they would do more
execution, in a less space of time, than the most active piece of
ordnance could effect; and they would also require fewer hands, as
the only necessary operation would be to light and dart them forward.

The fougette, called also in French the _Baguette à feu_, has
received improvements in France, which we will notice hereafter. In
favour of these improvements and their application, we are told,
that, to do execution at a distance, especially in sea-fights,
fougettes may be so made as that they may reach shipping at a great
distance, and with a given velocity.

The Congreve rocket is a new species of war-rocket, invented by Sir
William Congreve. This incendiary rocket drew the attention of the
European nations, after the attack of the British on Copenhagen;
where, we are informed, they did incredible execution. This rocket
may be considered to be a carrier of fire. Their effect, however,
in the Chesapeake, and elsewhere, during the late war, was very
trifling. They seemed, in fact, little calculated to injure and
more to intimidate.[38] They differ from the common rocket as well
in their magnitude and construction, as in the powerful nature of
their composition; which is such, that without the encumbrance of any
ordnance, (the rocket containing the propelling power wholly within
itself), balls, shells, case-shot and carcasses, may be projected to
the distance of one thousand to three thousand yards. The principle
of projectile force is so greatly increased, as not only to triple
the flight of small rockets so formed, but also to allow of the
construction of rockets of such dimensions, as, on the ordinary
principles of combination, would not even rise from the ground,
and of such powers of flight and burthen, as have hitherto been
considered altogether impracticable.

On the basis of this increase of power, Congreve has succeeded in
making this rocket. They are formed of various dimensions, as well in
length as in caliber, and are differently armed, according as they
are intended for the field, or for bombardment and conflagration;
carrying in the first instance either shells or case shot, and in
the second, for the purpose of destroying shipping, buildings,
stores, &c. a peculiar species of composition, which never fails
of destroying every combustible material with which it comes in
contact. The latter are called _carcass-rockets_, and were first
used at Boulogne in 1805, after many experiments, which were made
by Congreve, at Woolwich. The attack in 1806 was merely desultory,
in which not more than 200 rockets were fired. The town was set on
fire by the first discharge, and continued burning for near two days.
After the affair at Copenhagen, which established their reputation,
it appears that a committee of officers, who had witnessed their
effect in that bombardment, pronounced them to be "_a powerful
auxiliary to the present system of artillery._"

At the seige of Flushing, they appear to have been used with success,
and general Monnet, the French commandant, made a formal remonstrance
to lord Chatham respecting the use of them in that bombardment. The
rocket system was also tried with success, and the crown prince of
Sweden was the first general, who bore testimony to their effects
in this service. At the memorable battle of Leipzig, they proved,
we are informed, a powerful weapon, and also, when the British army
under Wellington, crossed the Adour. In 1814, a rocket-corps was
established in the British service.

General de Grave transmitted, to the Society of Encouragement of
Paris, a Congreve rocket, or an English incendiary rocket, which was
found on the French coast. M. Gay-Lussac examined it. The case was
made with gray paper, and painted. The inflammable matter was of a
yellowish-gray, and the sulphur was distinguishable with the naked
eye. It burnt with a quick flame, and exhaled sulphurous acid gas.

According to his analysis, (_Archives des Découvertes_, ii, 303), the
composition gave

Nitrate of potassa, 75.00
Charcoal, 1.6
Sulphur, 23.4
------
100
------

Gay-Lussac, after determining the proportions of the constituent
parts, made a composition of a similar kind, and charged a case,
which exhibited the same properties as the English rocket.

The great general point of excellence of the rocket system, if we
may judge from the account of English writers, is the facility with
which all the natures of this weapon may be conveyed and applied.
Its peculiar applicability to naval bombardment is said to rest on
this property, that there is no reaction, no recoil in the firing
of the largest rocket; so that by this means carcasses, equal to
those projected by the largest mortars, may be thrown from the
smallest boats. Its peculiar fitness for land service is, that it
is a description of extremely powerful ammunition without ordnance,
so that the burthen of mortars and guns is dispensed with, and all
that is to be carried is actual available missile matter, capable
of range, and of many of the most important effects of the heaviest
artillery. The rocket system, as a system of ammunition without
ordnance, is highly extolled by British writers.

We will now speak of their construction. All rockets designed
for service are cylindrical, having strong metallic cases, and
armed, as we before observed, either with carcass composition for
bombardment and conflagration, or with shells and case shot for
field service. They are, however, of various weights and dimensions,
from the eight-inch carcass or explosion rocket, weighing nearly
three hundred weight, to the six pound shell rocket, which is the
smallest size, used in the field. The sticks, which are employed for
regulating their flight, are also of different lengths, according to
the size and service of the rocket; and which, for the convenience
of carriage, are stowed apart from the rocket, and so contrived as
to consist of two or more parts, which are connected to it, and
to each other, when requisite, with the utmost expedition. The
32 pounder rocket carcass, which is the nature hitherto chiefly
used for bombardment, will range 3000 yards with the same quantity
of combustible matter as that contained in the 10 inch spherical
carcass, and 2500 yards with the same quantity as that of the 13
inch spherical carcass. The 12 pounder rocket case shot, which is
so portable that it may be used with the facility of musketry,
has a range nearly double that of field artillery, carrying as
many bullets as the 6 pounder spherical case. We may remark here,
that the projectile force of the rocket is well calculated for the
conveyance of case shot to great distances; because, as it proceeds,
its velocity is accelerated instead of being retarded, as happens
with any other projectile; while the average velocity of the shell
is greater than that of the rocket only in the ratio of 9 to 8.
Independent of this, the case shot conveyed by the rocket admits of
any desired increase of velocity in its range by the bursting of
powder, which cannot be obtained in any other description of case.

Rocket ammunition is divided into three classes, _heavy_, _medium_,
and _light_; the former including all those above 42 lbs., which are
denominated according to their caliber, as eight-inch, seven-inch,
&c. rockets; the medium including all those from 42 lbs. to 24 lbs.;
and the light embracing from 18 pounder to 6 pounder inclusive.

The carcass-rockets are armed with strong iron conical heads,
containing a composition as hard and solid as iron itself, and which,
when once inflamed, cannot be extinguished. A 32 pounder carcass
rocket will penetrate 9 feet in common ground. They have been known
to pierce through several floors, and through the sides of houses.
For field service, the 24, 18, 12, and 6 pounders are commonly used.
The ranges of the eight-inch, seven-inch, and six-inch rockets, are
from 2000 to 2500 yards, and the quantity of combustible matter,
or bursting powder, from 25 lbs. to 50 lbs. These sized rockets
are equally efficient for the destruction of bomb proofs, or the
demolition of strong buildings. The largest rocket that has yet been
constructed has not exceeded 300 weight. It is proposed, however, to
make them from half a ton to a ton in weight.

The 42 and 32 pounders, which are used in bombardment, will convey
from 7 lbs. to 10 lbs. of combustible matter each, and have a range
of upwards of 3000 yards. The 24 pounder is equal to the propelling
of the coehorn shell, or 12 pounder shot. It is, from the saving in
weight, generally preferred to the 32 pounder. The eighteen-pounder,
which is the first of the light nature of rockets, is armed with a
nine pound shot or shell; the twelve-pounder, with a six do.; the
nine-pounder, with a grenade; and the six-pounder, with a 3 lb. shot
or shell.

The following table presents a general view of the ranges,
elevations, and other particulars of several of the most useful
descriptions of Congreve rockets.

----------------------+---------------------------+-------+---------
| | |Elevation
| |Extreme| for
Nature of ammunition. | Armed with | range.| extreme
| | | range.
----------------------+---------------------------+-------+---------
| _Carcasses_, large, 18 } | |Elevation
42 Pounder carcass } |lbs. of combustible } | yards.|for
rockets. } |matter; small, 12 lbs. } | |extreme
|do. } | 3,500 |range,
| } | |not less
42 Pounder shell } | _Shells_, 5½, 12 pr. } | |than 60°
rockets. } |spherical. } | |
| | |
|_Carcasses_, large, 18 lbs.| yards.|
32 Pounder carcass } |of combustible matter; | 2,000 | 60°
rockets. } |medium 12 lbs. = 13 inch | |
|carcass; | 2,500 | { 60° to
| | | { 55°
|Small, 8 lbs. = 10 inch } | 3,000 | 55°
|carcass. } | |
| | |
32 Pounder shell } |shells, 9 pr. spherical. | 3,000 | 50°
rockets. } | | |
| | |
32 Pounder case } |Case { large 200 carbine | |
shot rockets. } |shot, { balls. | 2,500 | 55°
| { small 100 do. | 3,000 | 50°
| | |
|Strong iron containing } | |
32 Pounder explosion }|from 5 lbs. to 12 lbs. } | from }|
rockets. }|of powder, to burst } | 2500 }| 55°
|by fusées. } | 8000 }|
| | |
| { large 72 carbine | |
12 Pounder case } |Case { balls. | 2,000 | 45°
shot rockets. } |shot, { small, 48 carbine | |
| { balls. | 2,500 | 45°
----------------------+---------------------------+-------+---------

From the preceding table, it will be seen, that the 32 pounder
carcass rocket will range 3000 yards, with the same quantity of
combustible matter as that contained in a ten-inch spherical case,
and 2500 yards, with the same quantity as that of the thirteen-inch
spherical carcass. The twelve pounder case-shot rocket, which is so
portable that it may be used with the facility of musquetry, has
a range nearly double that of field artillery, carrying as many
bullets as the six pounder spherical case: add to which, that, from
the nature of the combination of the rocket, these bullets are
projected from it in any part of its track, with an increase of
velocity, by which its operation becomes frequently more destructive
at that point, where any different species of ammunition ceases to
be effective. Of this description of rocket-case-shot, one hundred
soldiers will carry into action, in any situation where musquetry can
act, 300 rounds, and 10 frames for discharging them; from each of
which, four rounds may be fired in a minute. Of the same description
of case-shot, four horses will carry 72 rounds, and four frames;
from which may be fired 16 rounds in a minute. The rockets used by
cavalry are twelve pounders, armed with a 6 pounder shell or case
shot; each horse carrying four of these rockets. To detail the
arrangement of the rocket corps, the weight of ammunition carried by
the troop horse, and other particulars, would require more space than
we can conveniently appropriate to these subjects.

We may remark, however, that the heavier species of rockets, as
the 32 pounder or 24 pounder, as also the 18 and 12 pounders, are
sometimes carried in cars of a peculiar description; which not only
convey the ammunition, but are contrived also to discharge each two
rockets in a volley, from a double iron-plate trough. This trough is
of the same length as the boxes for the sticks, and travels between
them; but being moveable, may, when the car is unlimbered, be shifted
into its fighting position, at any angle from the ground ranges, or
point blank, up to 45°, without being detached from the carriage.
The limbers are always in the rear. The rockets are fired with a
port-fire and long stick.

When used by infantry, one man in ten, carries a frame of a very
simple construction, standing on three legs like a theodolite, when
spread. It is mounted at top with an open cradle, from which the
rockets are discharged, either for ground ranges, or at any required
elevation.

When they are used for bombardment, they are discharged from frames
of a different, though simple, construction; and, in many cases, the
frames are dispensed with, as they are thrown from a battery, erected
for the purpose.

For the defence of a pass, or for covering the retreat of an army,
the rockets are laid in batteries of 100 or 500 in a row, according
to the extent of the ground to be protected. One man may fire the
whole.

With regard to their use in the naval service, some additional
remarks may be interesting.

We observed, that, in consequence of there being no reaction in
these projectiles on the point of discharge, rockets may be used in
the smallest boats of the navy. These rockets carry a quantity of
combustible matter, and, according to the ordinary system, would
require to be thrown from the largest mortars, and from ships of
very heavy tonnage. The 12 and 18 pounder have been fired from a
four-oared gig. They may be made to ricochet in the water at low
angles. In boarding, they have been recommended, to be thrown into
the port holes of the enemy. They have also been recommended for
fire-ships, in order to produce an extensive and devastating fire
among the ships of the enemy.

Besides the advantages, which rockets possess, and of which we have
spoken; namely, that it is a species of projectile, containing within
itself the propelling power, by which heavy ordnance is dispensed
with, and that an extensive fire may be kept up, by a few men,
against any important point; there is another advantage said to be
peculiar to them; _viz._ that they may be employed in a variety of
cases, in which the usual artillery, from the nature of the ground,
or other impediments, cannot be rendered effective; and that, in
several bombardments, in consequence of their trifling reaction,
they may be thrown from cutters and small boats, and, therefore,
from points, which could never be approached by the vessels, usually
employed in that service. With respect to the expense of the
formation of war-rockets, calculations have been made, by which it
appears, that their cost is less than the usual expense of carcasses.

We are informed on this head, that it is the cheapest of all
ammunition, depending on the projectile force of gunpowder. For a 32
pounder carcass rocket costs only 1_l._ 1_s._ 11_d._ complete for
service, and its equivalent, the 10 inch spherical carcass, with the
charge of powder necessary to convey it 3000 yards, which power is
contained in the rocket, costs 1_l._ 2_s._ 7_d._, independent of any
charge for the mortar, mortar bed, platform, difference of transport,
&c. A vessel of 300 tons will carry 5000 of them at least. But the
comparison, as to the expense, is still more in favour of the rocket,
when compared with the larger nature of carcasses. The 15 inch
spherical carcass costs 1_l._ 17_s._ 11-1/2_d._ to throw 2500 yards;
while its equivalent rocket costs but 1_l._ 5_s._ being a saving on
the first cost, of 12_s._ 11-1/2_d._

Notwithstanding all the encomiums, bestowed on the Congreve rockets
by the English, the French entertain a different opinion of them.
For the following remarks, we are indebted to Ruggeri, (_Pyrotechnie
Militaire_, p. 278), by which it appears, that Congreve was not the
original inventor. He acknowledges, however, that they experienced
the sad effects of them; and we do not offer this remark with
any sort of prejudice, but as an acknowledgment, that the French
experienced their "sad effects." Ruggeri says, that the Congreve
rocket is nothing more than he described in his _Elements of
Pyrotechny_ five years before they were known to the English. It is,
therefore, wrong, he adds, that we regard it as an English invention.
It was invented, says he, by a naval officer at Bordeaux, and ought
not, he further remarks, to be regarded as a useful weapon in war.
The reason he gives is, that its utility must depend upon places and
circumstances. If it is required, he adds, to attack a fleet, we must
employ two or three hundred before making any impression; because we
cannot direct a firing rocket, as a cannon or ball. This is certainly
a great inconvenience. He makes the cost also much greater than the
English calculation; namely, for a single one of them ten times
more than for a red-hot shot. Ruggeri, however, is candid enough to
say, that, notwithstanding he differs in opinion, he is far from
opposing any trials or experiments, made with the view of improving
or perfecting it; but is decidedly of opinion, that it can never be
employed at sea with the same advantage as bombs and cannon-ball.

Ruggeri published, in the _Journal of Paris_, in September, 1809,
a letter, in reply to a writer, who had published some reflections
on incendiary rockets, from which, as it throws some light on this
subject, we shall here introduce a few extracts:

"Although Monsieur, the _cannonier_ of Ostend, may not have given the
precise construction of the rocket, which we name the sky-rocket, and
of which the English have made so criminal a use, I will commence
at first by assuring you, that I coincide perfectly with him, in
the preference he gives to howitzes, bombs, and other projectiles,
which are used by civilized nations. He has very satisfactorily
demonstrated their advantages over the Congreve rocket. I will
only add, that bombs and howitzes have also the advantage of being
one-fifth cheaper, and projected with greater facility.

"The Congreve rocket cannot be of any particular advantage, because
it only carries fire to the place where it falls; and if we wish to
use them against any vessel whatever, it is impossible to assure
ourselves of a direction on a given point, as many difficulties occur
in projecting them.

"The merit of the invention of these rockets does not belong to the
English.

"This invention was made by a Frenchman, a captain of a privateer,
who made the first attempt to use them about seventeen years since,
(1795).

"The English have perfected, or rather have modified this rocket.

"It is sometime since I offered a kind of bomb, which may be used
with more facility than the common kind. This bomb has the advantage
over the Congreve rocket: 1st, Because it is less troublesome to
use; 2dly, It may be made of any diameter or size, and consequently
suited to all calibers; 3dly, The place and time of its fall is
readily determined; and fourth, and lastly, It bursts into pieces,
and attaches itself to all combustible bodies, with which it meets.

"It remains for me to say, that it is not the powder which moves the
rocket, but a composition almost as strong. The powder, which is used
in the Congreve rocket, is intended to destroy the machine after it
has produced its destructive effects." See _Pyrotechnie Militaire_,
p. 278.

The difference between incendiary rockets, and common signal rockets,
is in the interior. Instead of the furniture, or garnishing pot and
head, a conical head of sheet iron is substituted, in which several
holes are made to suffer the composition it contains to burn more
readily. The composition is the same as that for fire-rockets; but
is coarsely pulverized, and mixed with an equal quantity of the
composition of fire-lances. These rockets are employed with advantage
to burn a city, or vessels in a harbour. The cone, with which they
are capped, enables them to penetrate the roofs of houses, and set
them on fire.

_Sec. XXV. Sky-Rockets (Meurtrières.)_

The sanguinary or _murdering rocket_ is made in the same manner as
the preceding. They have neither head nor pot; but, in their place,
they are furnished with a cone of beaten or solid iron. This cone is
the appendage, or weapon, which produces such destructive effects.
These rockets, when they fall upon the troops of an enemy, wound
them very dangerously, without their being able to prevent it. The
advantage, more particularly derived, is, that they may be projected
from under cover, and to double the distance of ordinary musketry. To
make use of these rockets, a box is constructed, whose interior is
so arranged as to receive the rockets in regular order. They should
be placed in it with their sticks; and, therefore, the case must
be made sufficiently large to admit them. By this contrivance, the
rockets are sheltered from the fire and water. To discharge them, the
box is first inclined on the side next to the heads of the rockets,
and in the direction of the place, to which they are to be thrown. A
communication is made by leaders, in the manner already mentioned in
the preceding part of this work; so that, when the match is fired,
or a single rocket, they all are discharged at the same time. The
mode of firing rockets either singly or in numbers, the manner of
preparing the cases, the different compositions, and the operation
of filling, and of furnishing them, &c. are given in the preceding
part.

_Sec. XXVI. Of the Rocket Light-Ball._

Congreve also invented a species of light-ball, which, when thrown
into the air by means of one of his rockets, and having reached
the elevation of the rockets' ascent, is detached from it with an
explosion, and remains suspended in the air by a small parachute,
to which it is connected by a chain. Thus, in lieu of the transient
momentary gleam, obtained by the common light ball, a permanent
and brilliant light is obtained, and suspended in the air for five
minutes at least, so as to afford time and light sufficient to
observe the motions of an enemy, either on shore or at sea; where
it is particularly useful in chasing, and for giving distant and
more extensive night signals. It is to be observed, that nothing of
this kind can be obtained by the projectile force of either guns or
mortars; because the explosion infallibly destroys any construction,
that could be made to produce the suspension in the air.

We have seen no account of any experiments, which have been made with
it.

_Sec. XXVII. Of the Floating Rocket Carcass._

Congreve also applied his rocket, and the parachute, for the purpose
of conveying combustible matter to distances far beyond the range
of any known projectile force, at the same time that it is cheap,
simple, and portable. The floating carcass, like the light-ball, is
thrown into the air, attached to a rocket, from which being liberated
at its greatest altitude, and suspended to a small parachute, it
is driven forward by the wind, and will, in a moderate breeze,
afford ranges at least double those of the common carcass. It may,
therefore, for naval purposes, be thrown from a blockading squadron,
in great quantities, by a fair wind, against any fleet or arsenal,
without the smallest risk, or without approaching within range of
either guns or mortars. The rocket containing the carcass is no
larger than the 32 pounder carcass rocket; and the whole expense,
added to the rocket, does not exceed five shillings. Nor are the
approaches of the carcass itself necessarily visible by night; as it
may be so arranged, as not to inflame, till some time after it has
settled. It is evidently, therefore, capable of becoming a harassing
weapon, if the account of it be true; and, among large fleets and
flotillas, it may do as much injury as any other carcass, by lodging
unperceived in the rigging, or lighting on extensive arsenals, in
such situations, where other means of annoyance could not be used.

_Sec. XXVIII. Observations on Rockets._

The following remarks on the subject of rockets by M. Bigot, (_Traité
d'Artifice de Guerre_, p. 131,) may be interesting to the reader.

Authors, who have written on rockets, are of opinion, that the height
of the different kinds of rockets should not be increased on account
of their diameter; because, as the diameter increases, the rocket
also increases in weight and surface; and if augmented in height in
the same ratio, its power of ascension would be feeble. It is from
this reasoning, together with practice, that they have determined the
height of empty cases. Some have given the proportion of six times
their exterior diameter, and others again have made them a third
longer than the piercer. There has resulted from this difference
of opinion, such an irregularity in the formation of rockets, that
artificers or fire-workers were left in uncertainty as to the best
mode to be pursued. To avoid, however, this embarrassment, if we
consider the diameter of the base of the piercer of any kind of
rocket as one-third of the exterior diameter of the case, the small
end must be the one-sixth part of it; and the piercer and the cone
are of the same diameter, and the surface of the one is equal to
the surface of the other. We might conclude, accordingly, that the
increase of the height of the case, should be the same with all kinds
of rockets. It appears by different authors, that the ancient and
modern fire-workers have fixed the dimensions of rockets and their
piercers, by various experiments. If we take for granted all the
heights of the piercers, or the rockets themselves, we obtain a curve
of double or treble reflection, which is very evidently in opposition
to the above principles, and of the law which results from them.

Experiments prove, that to make a good rocket of half an inch in
diameter, the piercer must be five times and a third of the same
diameter; and for a rocket of three inches, the piercer, or broach,
as it is sometimes called, is only four times the diameter in height.
To determine, however, the height of the piercer in general, greater
than the preceding, it is found necessary to have some satisfactory
result, in order to employ, mathematically speaking, _less times_ of
the exterior diameter of the rocket. The half-inch and three-inch
rocket are the extremes of an increasing arithmetical progression;
and their equivalents, 5-1/3 and 4 diameters is the extreme of a
similar, but decreasing progress; but if we insert the same number
of arithmetical mean between the two extremes of each of these two
progressions, and then continue them indifferently, the terms of the
first will express the diameter of as many different cases; and those
of the second, the height of the corresponding piercers. They will
be, for instance, in the two following proportions:

÷ 6 7 8 9 10 11 12 13 14, &c. 36.

÷ 5-14/45 5-12/45 5-11/45 5-9/45 5-7/45 5-7/45 5-2/45 5-1/45 4-44/45 &c. 4.

The first of which has unity for its common difference. It has been
found, that, by inserting in each, a mean of 29, the height of the
piercers will correspond with the superior diameter, which is less,
or regulated by their respective diameters. Besides, as the diameters
go on augmenting, the rockets are proportionably increased in height,
but only in an inverse order, until the 58th term included, and
beyond which they decrease, until they become negative, which appears
to indicate that the term appertains to the diameter of the rocket,
and without any uncertainty.

It results from the intimate relation of these two progressions,
that, in stopping at the 58th term, if we bring back on an axis as it
were, the height of the piercers, we obtain a straight instead of a
curved line.

Bigot has given two tables relative to the construction of rockets,
and, as their use is seen by mere inspection, we here introduce them
without remark.

They comprehend the dimensions of rockets of different calibers,
compared with the exterior and respective diameter of each kind; and
relative to the dimensions of the tools of sky-rockets of different
calibers, and also compared with the exterior and respective diameter
of each.

It will be seen, on an examination of these tables, that all the data
are satisfactorily given; so that, in the construction of rockets,
the artificer will find them extremely useful, if not absolutely
necessary.

The principles on which these tables are founded, may be depended
on, inasmuch as M. Bigot has taken considerable pains on that
head; and, consequently, the calculations, which follow, and the
proportions, established for the construction of rockets in general,
are sufficiently conclusive.

(TABLE I: Part 1 of 3)
+-----------------+-----------++-----------------------------------------+
| |Diameter of|| Height of tools of wood. |
| |the rocket.|| |
| +-----+-----++-----------------------------------------+
| | | || Rammers, &c. |
+ | | ++------+----------------------------------+
| Name of the | | || | For charging the head not |
| Rocket. | | || | comprised. |
| | Ext | Int-|| +-------+---------+---------+------+
| |erior|erior||Roller| 1 | 2 | 3 |Solid4|
+-----------------+-----+-----++------+-------+---------+---------+------+
| |inch.|Diam.|| D. | D. | D. | D. | D. |
|Small Partement, | ½ | ⅔ || 24 |6⅓ |4-5/9 |2-7/9 |1⅓ |
|Partement, | ¾ |idem.|| 16 |6-2/9 |4-13/27 |2-6/27 |idem. |
|Marquise, | 1 |idem.|| 12 |6-1/12 |4-7/18 |2-25/36 |idem. |
|Double marquises | 1¼ |idem.|| idem.|5-14/15|4-13/45 |2-29/45 |idem. |
|Ditto, for 4 doz.| 1½ |idem.|| 10 |5-7/9 |4-5/27 |2-16/27 |idem. |
|Rocket of | 2 |idem.|| 9 |5⅜ |3-31/36 |2-25/72 |1⅙ |
|Ditto, | 2½ |idem.|| 8⅖ |5-1/15 |3-29/45 |2-2/9 |1-2/15|
|Ditto, | 3 |idem.|| 8 |4-7/9 |3-4/9 |2-1/9 |1-1/9 |
|Ditto, | 4 |idem.|| 6⅚ |4¼ |3-3/32 |1-15/16 |1⅛ |
|Ditto, | 5 |idem.|| 6 |3-43/60|2-133/180|1-137/180|1-7/60|
+-----------------+-----+-----++------+-------+---------+---------+------+

(TABLE I: Part 2 of 3)
+-----------------+-----------++-----------------------------------------+
| |Diameter of|| Height of | Diameter of the |
| |the rocket.||tools of wood| tools of wood. |
| +-----+-----++-------------+-----+------+------+-------+
| | | || | | Rammers. | | |
+ | | || | +-----+------| | |
| Name of the | | || | | | | | |
| Rocket. | | || | Con- | | | |Sockets|
| | Ext | Int-|| | ical | To | To | Of | of the|
| |erior|erior|| Pot. | head | run |charge| pots.| pot. |
+-----------------+-----+-----++------+------+-----+------+------+-------+
| |inch.|Diam.|| D. | D. | D. | D. | D. | D. |
|Small Partement, | ½ | ⅔ || 3 |1⅔ | ⅔ |7/12 |1⅔ | ⅔ |
|Partement, | ¾ |idem.|| 2⅔ |1-5/9 |idem.|11/18 |1-5/9 | 7/9 |
|Marquise, | 1 |idem.|| 2⅓ |1½ |idem.|idem. |1½ | ⅚ |
|Double marquises | 1¼ |idem.|| 2⅕ |1-8/15|idem.| ⅗ |1-8/15| 13/15 |
|Ditto, for 4 doz.| 1½ |idem.|| 2 |1½ |idem.|11/18 |1½ | ⅚ |
|Rocket of | 2 |idem.|| 1¾ |idem. |idem.| ⅝ |idem. | ⅞ |
|Ditto, | 2½ |idem.|| 1½ |idem. |idem.|19/30 |idem. | 9/10 |
|Ditto, | 3 |idem.|| 1⅓ |idem. |idem.|23/36 |idem. | 11/12 |
|Ditto, | 4 |idem.||1-1/16|idem. |idem.|31/48 |idem. | 15/16 |
|Ditto, | 5 |idem.|| 9/10|idem. |idem.|13/20 |idem. | 14/15 |
+-----------------+-----+-----++------+------+-----+------+------+-------+

(TABLE I: Part 3 of 3)
+-----------------+-----------++---------------+------------------+
| |Diameter of||Diameter of the| Dimension of |
| |the rocket.|| tools of wood.| mallets. |
| +-----+-----++-------+-------+---------+--------+
| Name of the | | || | | | |
| Rocket. | | ||Base of| | | |
| | Ext | Int-||conical| | | |
| |erior|erior|| head. | Ladle.|Diameter.| Length.|
+-----------------+-----+-----++-------+-------+---------+--------+
| |inch.|Diam.|| D. | D. | inches. | inches.|
|Small Partement, | ½ | ⅔ || 1⅔ | ⅔ | 2¾ | 3⅓ |
|Partement, | ¾ |idem.|| 1-5/9 | idem. | 2¾ | 3⅓ |
|Marquise, | 1 |idem.|| 1½ | idem. | 3½ | 4¼ |
|Double marquises | 1¼ |idem.|| 1-8/15| idem. | 3½ | 4¼ |
|Ditto, for 4 doz.| 1½ |idem.|| 1½ | idem. | 4 | 5 |
|Rocket of | 2 |idem.|| idem. | idem.}| | |
|Ditto, | 2½ |idem.|| idem. | idem.}| | |
|Ditto, | 3 |idem.|| idem. | idem.}| 5½ | 6⅔ |
|Ditto, | 4 |idem.|| idem. | idem.}| | |
|Ditto, | 5 |idem.|| idem. | idem.}| | |
+-----------------+-----+-----+--------+-------+---------+--------+

(TABLE II: Part 1 of 3)
+----------------+-----------++-----------------------------------+
| |Diameter of|| HEIGHT OF |
| | rockets. ||--------+--------+-------+---------+
| +-----+-----++ |Charged | | |
| Name of the | | || |rockets,| | |
| Rockets. | Ext-| Int-|| Empty |button, |Massive| |
| |erior|erior|| cases.|&c.incl.|Rockets|Piercers.|
+----------------+-----+-----++--------+--------+-------+---------+
| |inch.|Diam.|| D. | D. | D. | D. |
|Small partement,| ½ | ⅔ || 7⅓ | 6⅚ | ⅔ | 5⅓ |
|Partement, | ¾ |idem.|| idem. | 6-7/9 | idem. | 5-2/9 |
|Marquise, | 1 |idem.|| 7-7/12 | 6-7/12 | idem. | 5-1/12 |
|Double marquise | 1¼ |idem.|| 7 | 6-7/15 | idem. | 4-14/15 |
| of 3 doz. | | || | | | |
|Ditto, 4 doz. | 1½ |idem.|| 6-7/9 | 6-5/18 | idem. | 4-7/9 |
|Rocket of | 2 |idem.|| 6⅜ | 5⅞ | ½ | 4-13/24 |
|Ditto, | 2½ |idem.|| 6-1/15 | 5-17/30| 7/15 | 4-4/15 |
|Ditto, | 3 |idem.|| 5-7/9 | 5-5/18 | 4/9 | 4 |
|Ditto, | 4 |idem.|| 5¼ | 4-73/76| 11/24 | 3-15/32 |
|Ditto, | 5 |idem.|| 4-43/60| 4-13/60| 9/20 | 2-14/15 |
+----------------+-----+-----++-------+--------+--------+---------+

(TABLE II: Part 2 of 3)
+----------------+-----------++------------------------------------+
| |Diameter of|| HEIGHT OF |
| | rockets. ||--------+-------+-----------+-------+
| +-----+-----++ | |Total of | |
| Name of the | | || Button | |the piercer| |
| Rockets. | Ext-| Int-||& their | |and culot | |
| |erior|erior||cylinder|Culots.|comprised. | Screw.|
+----------------+-----+-----++--------+-------+-----------+-------+
| |inch.|Diam.|| D. | D. | D. | D. |
|Small partement,| ½ | ⅔ || ⅔ | 1⅔ | 7⅔ | ¼ |
|Partement, | ¾ |idem.|| idem. | idem. | 7-5/9 | 2⅔ |
|Marquise, | 1 |idem.|| idem. | idem. | 7-1/12 | 2½ |
|Double marquise | 1¼ |idem.|| idem. | 1⅕ | 6⅘ | 2 |
| of 3 doz. | | || | | | |
|Ditto, 4 doz. | 1½ |idem.|| idem. | 1-1/18| 6½ | 1⅚ |
|Rocket of | 2 |idem.|| idem. | ⅞ | 6-1/12 | 1½ |
|Ditto, | 2½ |idem.|| idem. | ⅘ | 5-11/15 | 1-3/10|
|Ditto, | 3 |idem.|| idem. | ⅔ | 5⅓ | 1⅙ |
|Ditto, | 4 |idem.|| idem. | ½ | 4-61/96 | 15/16 |
|Ditto, | 5 |idem.|| idem. | ⅖ | 4 | ⅘ |
+----------------+-----+-----++--------+-------+-----------+-------+

(TABLE II: Part 3 of 3)
+----------------+-----------++----------------------------------------+
| |Diameter of|| Diameter of the parts of the piercer. |
| | rockets. ||------+--------+---------+------+--- ---+
| +-----+-----++ | | | | |
| Name of the | | || |Exterior| Button | |Screw |
| Rockets. | Ext-| Int-|| |of small| and | |at the |
| |erior|erior|| Base.| end. |cylinder.|Culot.| base. |
+----------------+-----+-----++------+--------+---------+------+-------+
| |inch.|Diam.|| D. | D. | D. | D. | D. |
|Small partement,| ½ | ⅔ || ⅓ | ⅙ | ⅔ | 1 | 1 |
|Partement, | ¾ |idem.|| idem.| idem. | idem. | idem.| 7/9 |
|Marquise, | 1 |idem.|| idem.| idem. | idem. | idem.| ⅔ |
|Double marquise | 1¼ |idem.|| idem.| idem. | idem. | idem.| ⅗ |
| of 3 doz. | | || | | | | |
|Ditto, 4 doz. | 1½ |idem.|| idem.| idem. | idem. | idem.| 5/9 |
|Rocket of | 2 |idem.|| idem.| idem. | idem. | idem.| ½ |
|Ditto, | 2½ |idem.|| idem.| idem. | idem. | idem.| idem. |
|Ditto, | 3 |idem.|| idem.| idem. | idem. | idem.| idem. |
|Ditto, | 4 |idem.|| idem.| idem. | idem. | idem.| 5/12 |
|Ditto, | 5 |idem.|| idem.| idem. | idem. | idem.| ⅖ |
+----------------+-----+-----++------+--------+---------+------+-------+

_Note._ The rockets of two inches, and those between that and three
inches, require to be beaten with four rammers, independently of that
which is solid; and also those above three inches, require five. The
rolling board should be sufficiently large for the cases we wish to
form; _viz._ one of twenty-eight inches in length, and six inches
in breadth for small rockets; one of thirty inches in length, and
ten inches in breadth for middlesized rockets; and one of thirty-six
inches by eighteen for the largest rockets.

_Sec. XXIX. Of the Succouring Rocket._

The succouring, or marine rocket, is a name given to a rocket, which
is sufficiently large to convey a small cord or rope to some distance
from a vessel, and by its means to save the lives of persons in
danger of shipwreck. Rockets for this purpose should be at least two
inches in interior diameter. The rod should be of the same length and
thickness as a rocket of half this caliber. To this rod is tied the
cord, which must be light, and yet strong, and when the rocket is
fired, the string should be arranged loose, so that no impediment is
experienced in the flight of the rocket.

The applications of the succouring rocket are two in particular:
_viz._ In case a seaman should fall overboard, and in case of
shipwreck; in the former, to throw a cord to some distance, and in
the latter, to convey a cord from the ship to the shore, should a
vessel be stranded on a beach. Several methods have been proposed for
the same purpose, namely, that of conveying a line or rope to shore,
when the surf is too high for a small boat to live in it.

The invention of lieut. Bell, described in the _Annales des Arts
et Manufactures_, and in the _Archives des Découvertes_, ii, 120,
is designed for a similar purpose as the succouring rocket. Mr.
Bell's invention consists simply in throwing a rope from a vessel
by means of a mortar, attaching it to a shell, in order to make
a communication from a vessel in danger to the shore. For this
contrivance, he received one hundred guineas.

Several experiments were made with it, which were satisfactory.

In the essays, published by Mr. Fulton, a contrivance of this kind
is suggested, using, however, an instrument similar to a harpoon, to
which a rope is attached. This harpoon is thrown by a long gun. It is
calculated, also, as the harpoon for this purpose is furnished with
several barbs, to pierce and secure an enemy's vessel.

_Sec. XXX. Of the Greek Fire._

It is not known precisely what the composition of the Greek fire
was. It was invented by Callinicus of Hellipolis, a town in Syria,
who used it with so much skill and effect during a naval engagement,
that he destroyed a whole fleet belonging to the enemy, in which
were embarked thirty thousand men. It is defined to be a sort of
artificial fire, which insinuates itself beyond the surface of the
sea, and which burns with increased violence, when it mixes with
water. Its directions are contrary to the course of natural fire; for
the flames, we are told, will spread themselves downwards, to the
right or left, agreeably to the moment that is given.

It was used in the year 1679, and was known and used in 1291. It was
certainly liquid, and employed in many different ways; but, chiefly,
on board ships, being thrown from large engines on the ships of the
enemy. This fire was sometimes kindled in particular vessels, which
might be called fire-ships, and which were introduced among a hostile
fleet. Sometimes it was put into jars and other vessels, which were
thrown at the enemy by means of projectile machines; and sometimes
it was squirted by soldiers from hand-engines, or, as it appears,
blown through pipes. This fire was discharged from the fore part of
ships, by a machine constructed of copper and iron, the extremity of
which resembled the open mouth and jaws of a lion or other animal.
They were painted, and even gilded, and, it appears, were capable of
projecting the fire to a great distance.

Professor Beckman, who examined all the ancient authors respecting
the Greek fire, expressly says, that the machines which the ancients
employed to throw this fire were _spouting engines_. He also observes
(_History of Invent._ iv, p. 85) that "John Cameniata, speaking of
his native city, Thessalonica, which was taken by the Saracens in the
year 901, says, that the enemy threw fire into the wooden works of
the besieged, which was blown into them by means of tubes, and thrown
from other vessels. This passage, which I do not find quoted in any
of the works that treat on the Greek fire, proves, that the Greeks,
in the beginning of the tenth century, were no longer the only
people acquainted with the art of preparing this fire, the precurser
of our gunpowder. The Emperor Leo, who about the same period wrote
his art of war, recommends such engines, with a metal covering, to
be constructed in the fore part of ships; and he twice afterwards
mentions engines for throwing out Greek fire. In the east, one may
easily have conceived the idea of loading some kind of pump with the
Greek fire; as the use of a forcing pump for extinguishing fires was
long known there before the invention of Callinicus."

Writers differ considerably as to the composition of Greek fire,
properly so called, as there were many preparations, some hundred
years after the discovery, which went under the name of Greek fire.
Certain it is, that the Greeks had a knowledge of a very highly
combustible preparation, which water would not extinguish, and which,
from its nature, must have had the property of decomposing water
itself, or possessed so much oxygen, as to support the combustion of
the inflammable substances, even in contact with water.

Mr. Parke, (_Chem. Catechism_, p. 465), speaking of some of the uses
of nitre or saltpetre, says, that "for the same purposes it was
used by the ancients in that destructive composition of antiquity,
the Greek fire. Sulphur, rosin, camphor, and other combustibles,
were melted with it, and in this melted mass, woollen cords were
dipped, which were afterwards rolled up for use. These balls being
set on fire were thrown into the tents, &c. of the enemy, and as
the combustibles were furnished with a constant supply of _oxygen_
from the nitre, nothing could extinguish them." He also observes:
"For many centuries, the method of making this dreadful article
of destruction was lost; but it has just been discovered by the
librarian of the elector of Bavaria, who has found a very old latin
manuscript, which contains directions for preparing it."

It appears, however, that it could only be extinguished by urine,
sand, &c. James (_Mil. Dic._ p. 329) says, "it is composed, or made
up of naphtha, sulphur, bitumen, gum, and pitch, and it can only be
extinguished by vinegar, mixed with urine and sand, or with undressed
leather and green hides."

The author of a French work, _Œuvres Militaires_, says, that a
powerful composition, which is not extinguishable with water, may
be made of the following substances: _viz._ pitch, rosin, tallow,
camphor, turpentine, saltpetre, liquid varnish, oil of sulphur,
linseed, rock oil, flax, and charcoal finely pulverized. The whole is
melted together and boiled, and before it grows cold, quicklime in
powder is added. It is said to be susceptible of the most subtile and
destructive fire.

Bertrandon de la Brocquiere, who was in Palestine in 1432, as
counsellor to the Duke of Burgundy, observes, that the Moors were
then in possession of the Greek fire. He was present at Barrat,
during one of the Moorish celebrations. "It began," says he, "in the
evening at sun set. Numerous companies, scattered here and there,
were singing and uttering loud cries. While this was passing, the
cannon of the castle were fired, and the people of the town launched
into the air, '_bien hault et bien loing, une maniére de feu plus
gros fallot que je veisse oncques allume_.' They told me, they made
use of such at sea, to set fire to the sails of an enemy's vessel. It
seems to me, that as it is a thing easy to be made, and at a little
expense, it may be equally well employed to burn a camp or a thatched
village, or in an engagement with cavalry, to frighten their horses.

"Curious to know its composition, I sent the servant of my host to
the person who made this fire, and requested him to teach me this
method. He returned for answer, that he dared not, for that he should
run great danger, were it known; but as there is nothing a Moor will
not do for money, I offered him a ducat, which quieted his fears, and
he taught me all he knew, and even gave me the moulds in wood, with
the other ingredients, which I have brought to France."

Although La Brocquiere may have brought the secret to Europe, yet it
does not appear to have been used.

We may justly conclude, that the present gunpowder possesses
superior advantages to the Greek fire, and some authors, as Ruggeri,
are of opinion, that the account we have of it, that of its fire
_descending_, and the like, are exaggerated.

Porta, (_Magie Naturelle_), in treating of this subject, observes,
that the Greek fire was composed of the charcoal of willow, salt,
burnt brandy, sulphur, pitch, frankincense, flax, and camphor, and
that camphor alone has the effect of burning in water. He remarks
also, that, when Constantinople was attacked, the emperor Leon burnt
the vessels, or boats, to the number of 1800, by means of the Greek
fire. The _Journal des Savants_, 1676, p. 148, speaks of the origin
and use of the same fire.

In 1249, at the siege of Damietta, the French experienced the fatal
effects of it. The _Journal des Savants_ for 1666, mentions a machine,
which, when applied against a vessel, communicates fire to it
immediately, without injuring the person who uses it. In the _French
papers_ for 1797, M. Chevalier announced, that he had invented an
inextinguishable incendiary fuse, which is thrown by fire arms,
and calculated to set fire to the rigging of ships. In 1759, Dr.
Dupré published in the _French Journals_, that he had invented a
composition, which had the same properties and effects as the ancient
Greek fire, and that he possessed the means of extinguishing it. An
experiment was made at Versailles to the satisfaction of all, and
the secret was purchased by Louis XV. The Rev. J. P. Coste, in 1794,
laid before the French national convention, a new invention, for the
purpose of war, consisting of a carcass composition, which nothing
could extinguish, and which resembled in that respect the Greek fire.

Thevenot (_Travels in the Levant_), says, that in the 52d year of the
Hegira, (Anno Domini 672), Constantinople was besieged in the reign
of Constantine Prognates, by Yesid, the son of Moavia, the first
caliph of the family of the Ammiades; when the _Greek_ emperor found
himself so pressed, that he was almost reduced to despair. But the
famous engineer, Callinicus, invented a kind of _wild fire_, which
would burn under water, and by this means destroyed the whole fleet.

Gibbon (_History of the Decline and Fall of the Roman Empire_, vol.
vii, p. 282), speaks also of the Greek fire, and observes, that the
deliverance of Constantinople may be chiefly ascribed to it. It
appears, that Callinicus, the inventor, deserted from the service of
the Caliph to that of the Emperor; and Gibbon is of opinion, that
this discovery or improvement of the military art, was fortunately
reserved for the distressful period, when the degenerate Romans of
the east were incapable of contending with the warlike enthusiasm
and youthful vigour of the Saracens. He is of opinion, that little
or no credit can be given to the Byzantine accounts, as to the
composition of this fire; although, from their obscure and fallacious
hints, it should seem that the principal ingredient was naphtha,
a liquid bitumen which springs from the earth.[39] This was mixed
with sulphur, and with the pitch, extracted from the evergreen firs,
according to the testimony of Anna Commena, (_Alexid_, l. xiii, p.
383), and Leo, in the xixth chapter of his _Tactics_, speaks of the
new invention.

Gibbon describes its effects much as we have stated, viz. that the
fire was strong and obstinate, and was quickened by water; that
sand, urine, and vinegar were the only agents that could damp its
fury; that it was used for the annoyance of the enemy, both by sea
and land, in battles or in sieges, and was either poured from the
rampart in large boilers, or lanched into red-hot balls of stone and
iron, or darted in arrows and javelins, twisted round with flax and
tow, which had deeply imbibed the inflammable oil; that, at other
times, it was deposited in fire ships, or blown through long tubes of
copper, fixed on a prow of a galley; that its composition was kept
secret at Constantinople, pretending that the knowledge of it came
from an angel to the first and greatest of the Constantines, with a
sacred injunction not to divulge it under any pretext, &c. He also
observes, that, after it was kept secret above four hundred years,
and to the end of the 11th century, the method of preparing it was
stolen by the Mahometans, who employed it against the crusaders.
A knight, it appears, who despised the swords and lances of the
Saracens, relates, with heartfelt sincerity, his own fears, at the
sight and sound of the mischievous engine, that discharged a torrent
of the Greek fire, the _feu Gregeois_, as it is styled by the more
early of the French writers. "It came flying through the air," says
Gibbon, quoting Joinville, (_Histoire de St. Louis_) "like a winged
long tailed dragon, about the thickness of a hogshead, with a report
of thunder and the velocity of lightning; and the darkness of the
night was dispelled by this deadly illumination. The use of the
Greek, or as it might now be called, Saracen fire, was continued
to the middle of the 14th century, when the scientific or casual
compound of nitre, sulphur, and charcoal, effected a new revolution
in the art of war, and the history of mankind."

Ramsay, our learned historian, (_Universal History_, vol. ii, p.
150), gives the same account of the Greek fire. Morse, in his
_Universal Geography_, page 588, observes, that naphtha forms springs
in Persia, and, when scattered on the sea, it burns, and the flame is
often wafted to a great distance.

For remarks respecting the naphtha of Persia, and the universal fire
of the followers of Zoroaster, see the article on _Naphtha_. In
naphtha districts, the quantity of inflammable air is so great, that
it is used for fuel.

Since writing the above, we have examined Ruggeri, (_Pyrotechnie
Militaire_, p. 289), and find nothing new. He states the composition
of Greek fire, on the authority of others, to consist of naphtha,
sulphur, bitumen, camphor, and petroleum; that it was invented by
Callinicus, and employed against the Saracens as an incendiary; that
Pliny, in his time, mentioned a combustible substance, which was
thrown upon armed men, and burnt and destroyed them in the midst of
the battle; that it was employed successfully by the successors of
Constantine, and its composition was kept a state secret; that the
Turks used it, or a composition of a similar nature, at the siege of
Damieta, in 1249, forty-five years after the death of Roger Bacon;
and, finally, that, when the composition and effects of gunpowder
became known, the Greek fire, although it laid the foundation of the
invention of gunpowder, was no longer in use, and the secret of the
original preparation became lost. See _Gunpowder_.

_Sec. XXXI. Of Mines and Mining._

A mine is a subterraneous passage, dug under the wall or rampart of
a fortification, for the purpose of blowing it up by gunpowder; and
mining is the art of accomplishing this effect.

The art of mining, having become one of the most essential parts
of the attack and defence of places, should be well understood;
and requires a perfect knowledge of heights, depths, breadths, and
thicknesses; to judge perfectly of slopes and perpendiculars, whether
they be such as are parallel to the horizon, or such as are visual;
together with the true levels of all kinds of earth. To this may
be added, a knowledge of rocks, clays, soil, &c. and the effect of
gunpowder.

Mines were made long before the invention of gunpowder. The ancients
made galleries, or underground passages, much in the same manner
as the moderns, from without, under the walls of places, which
they cut off from the foundation, and supported with strong props.
The intervals were filled with all manner of combustibles, which,
being set on fire, burnt their props, and the wall, being no longer
supported, fell, by which a breach was made.

The besieged also made underground passages, from the town, under the
besiegers' machines, by which they battered the walls, to destroy
them, proving that necessity has been the inventress of mines.

The first mines we read of, since the invention of gunpowder, were
made in 1487, by the Genoese, at the attack of Serezanella, a town in
Florence. These, however, failed, and they were neglected, till Peter
Navarro, being then engineer to the Genoese, and afterwards to the
Spaniards, in 1503, against the French, at the siege of the castle
del Ovo, at Naples, made a mine under the wall, and blew it up; in
consequence of which the castle was taken by storm. Valliers says,
that the engineer was Francis George, an Italian.

The place where the powder is lodged, is called the chamber of the
mine, or _fourneau_, and the passage leading to the powder, is called
the gallery. The line of the least resistance, is the line drawn
from the centre of the chamber, perpendicular to the surface of the
ground; and the excavation, called the crater, is the pit or hole,
made by springing the mine.

Counter-mines are those made by the besieged, whereas mines are
generally made by the besiegers. Both mines and counter-mines, are
made in the same manner, and for like purposes, viz. to blow up their
enemies and their works.

Galleries, made within the fortification, before the place is
attacked, and from which several branches are carried to different
places, are generally 4 and 4-1/2 feet wide, and 5 or 5-1/2 feet
high. The earth is supported from falling in, by arches and walls, as
they are to remain for a considerable time. But when mines are made
to be used in a short time, then the galleries are but 3 or 3-1/2
feet wide, and 5 feet high, and the earth is supported by wooden
frames, or props.

The gallery being carried on to the place, where the powder is to be
lodged, the miners make the chambers. This is generally of a cubical
form, large enough to hold the wooden box, which contains the powder
necessary for the charge. The box is lined with straw and sand bags,
to prevent the powder from contracting dampness.

The chamber is sunk rather lower than the gallery, if the soil
permits; but where water is to be apprehended, it must be made higher
than the gallery; otherwise the besieged will let in the water, and
spoil the mine.

The fire is communicated to the mine by a pipe, or hose, made
of coarse cloth, whose diameter is about 1-1/2 inches, called a
_saucisson_, (for the filling of which, near half a pound of powder
is allowed to every foot), extending from the chamber to the entrance
of the gallery, to the end of which is fixed a match, that the miner
who sets fire to it, may have time to retire before it reaches the
chamber.

To prevent the powder from contracting any dampness, the saucisson
is laid in a small trough, called an _auget_, made of boards 3-1/2
inches broad, joined together lengthwise, with straw in it, and round
the saucisson, with a wooden cover nailed upon it.

The quantity of powder, required to charge mines, depends upon the
nature of the soil. That which is more tenacious, will require the
greatest force to separate its parts. The density may be learned,
comparatively speaking, by determining the specific gravity of each
kind of soil. The requisites in mining may be ascertained by four
simple problems, which relate to the nature of the soil, the diameter
of the excavation, the line of least resistance, and the charge.

_Table of the quantity of Gunpowder, to raise a cubic fathom of
different kinds of Soil._

The gallery and chamber being ready to be loaded, a strong box of
wood is made of the size and figure of the chamber, being about
one-third or one-fourth larger than is required for containing the
necessary quantity of powder. Against the sides and bottom of the
box is put some straw, and this straw is covered over with empty
sand bags, to prevent the powder from contracting any dampness. A
hole is made in the side, next the gallery, near the bottom, for
the saucisson to pass through, which is fixed to the middle of the
bottom, by means of a wooden peg, to prevent its loosening from the
powder, or to hinder the enemy (if he should reach the entrance) from
being able to tear it out. This done, the powder is brought in sand
bags, and thrown loosely in the box, and covered also with straw and
sand bags. Upon this is put the cover of the box, pressed down very
tight with strong props; and, to render them more secure, planks are
also put above them, against the earth, and wedged in as fast as
possible.

This done, the vacant spaces between the props are filled up with
stones and dung, and rammed in the strongest manner. The least
neglect in this work will considerably alter the effect of the mine.
Then the auget, or small trough, is laid from the chamber to the
entrance of the gallery, with some straw at the bottom; and the
saucisson laid in it, with straw over it. Lastly, it must be shut
with a wooden cover, nailed upon it. Great care must be taken in
stopping up the gallery, not to press too hard upon the auget, for
fear of spoiling the saucisson, which may hinder the powder from
taking fire, and prevent the mine from springing. The gallery is
stopped up with stones, earth and dung, well rammed, six or seven
feet further from the chamber than the length of the line of the
least resistance.[40]

Before closing this article, short as it is, compared with a full
view of the subject, which belongs exclusively to engineering, we
shall notice, from Belidor, the _globe of compression_ in mines. If
we imagine a large globe of earth, homogeneous in all its parts, and
a certain quantity of powder lodged in its centre, so as to produce
a proper effect without bursting the globe; by setting fire to the
powder, it is evident that the explosion will act all round, to
overcome the obstacles which oppose its motion; and as the particles
of the earth are porous, they will compress each other in proportion
as the flame increases, and the capacity of the chamber increases
likewise: but the particles of the earth next to the chamber will
communicate a part of their motion to those next to them, and those
to their neighbours; and this communication will thus continue in a
decreasing proportion, till the whole force of explosion is entirely
spent; and the particles of earth beyond this term will remain
in the same state as they were at first. The particles of earth,
that have been acted upon by the force of explosion, will compose
a globe, which Mr. Belidor calls the globe of _compression_. He
observed, that, when a mine exploded, and threw up the ground over
it, its action was, at the same time, felt in a circular direction,
throughout the surrounding ground, to a distance at least equal to
the oblique line drawn from the centre of inflammation to the edge of
the funnel.

Mines and counter-mines are now called offensive and defensive mines.
The hole made by the explosion is called the _entonnoir_, crater, or
funnel.

In the system of counter-mines, we have the _magistral gallery_, or
gallery of the counterscarp, which is that extended below the covered
way, from which branches are pushed to overthrow the works and
batteries of the beseiger, that crown it; the _enveloping gallery_
that communicates with the other passages, called the _galleries of
communication_, and is nearly parallel with the first at the distance
of from forty to sixty yards. Other galleries are pushed forward,
leaving the enveloping gallery, projecting at least thirty yards, and
having spaces between them of about fifty yards in width; so that
the enemy's miner, whose work may be heard under ground about thirty
yards, may not pass between any two of them without being discovered.
These are called _listening galleries_. It may be observed, that,
from these galleries, branches are carried forward to establish
chambers under the works of the enemy. Those who wish to acquire
information on this, and other subjects, connected with attack and
defence, and on some branches of engineering, would do well to
consult the French work of _Bousmard_.

There are likewise small mines called _Fougasses_, used in the
defence of field works. They are seldom more than ten feet beneath
the surface, and are placed at the expected points of attack, usually
nine feet from the salient angles, and without the counterscarp. The
chest of powder and the saucisson are placed as usual. Barrels or
casks and even grenades are used.

_Sec. XXXII. Of the Means of Increasing the Strength of Gunpowder for
Mining._

We mentioned, in the article on gunpowder, that quicklime had the
effect of increasing its strength. It has been suggested, to employ
quicklime, for this purpose, when gunpowder is used in mining.

Bottée and Riffault (_Traité de l'art de Fabriquer la Poudre à canon,
p. 301_) have given the result of some experiments on this subject,
which we purpose to notice. These experiments, however, are not
satisfactory on this head.

Dr. Baine, a physician of Foxano, in Tuscany, was the first who
announced the fact, that quicklime would increase the explosive
effect of gunpowder. The increase he states to be one-third.
The proportions are, twenty-three grammes of quicklime, and one
_kilogramme_ of powder.[41] The quicklime is powdered, and mixed with
the gunpowder.

Various experiments were made, with the eprouvette of Regnier, which
did not establish the truth of Dr. Baine's assertion. The Tuscan
hunters use gunpowder mixed with lime.

The experiments were made by M. L. Maitre and colonel Charbonel. They
employed pure dry powder, dry powder mixed with quicklime, moist
powder pure, and moist powder mixed with lime. The object of these
experiments was to ascertain, if the presence of quicklime added to
the force of powder; either as a fourth component part and acting
chemically, or by absorbing the moisture which the powder contains.

The charge of each was three ounces.

The result of the experiments is thus given:

Powder, dry and pure, 738 feet 2 inches.
Powder, dry, and mixed with quicklime, 690 -- 1 --
---- ----
Difference in favor of dry powder, 48 1

Powder, moist and pure, 714 feet 1 inch.
Powder, moist, and mixed with quicklime, 642 -- 2 --
---- ----
Difference in favor of moist powder, 71 11

It has been asserted, that the force of gunpowder is increased by
water, alcohol, and ether, in consequence of the great expansibility
of these fluids; but, according to the experiments of Bottée and
Riffault, the range of the ball was much less when the three fluids
were used successively, than when the dry and pure gunpowder alone
was employed. We are informed by a gentleman, who saw the experiment
made, that when gunpowder is mixed with an equal weight of fine saw
dust, and fired, it will give the same range to a ball as the same
weight of unmixed powder.

We find that col. Gibbs, (_American Journal of Science_, i. 87), in a
letter to professor Silliman, mentions the use of lime in increasing
the strength of gunpowder. He gives a certificate of the person,
whom he employed in blowing rocks, in which he used quicklime along
with powder, in the proportion of one part of the former to two of
the latter. In the certificate, it is stated, that a charge of this
mixture was found to be equally powerful, or to "answer equally well
with a like quantity of gunpowder," having made upwards of fifty
blasts in this manner, and, as he states, several hundred in the
usual way. He remarks, however, that, when the powdered lime was
mixed with the gunpowder the day before, the effect was diminished.
The colonel attributes the effect to the desiccation of the powder
by the lime; and, as gunpowder absorbs more or less water, the
lime, in its caustic state, takes it from the powder. If the lime
should remain too long, he is of opinion that it would probably
attack the water of crystallization of the saltpetre, and, according
to count Rumford's idea, destroy a great part of the powder. "The
examination of this subject," says Gibbs, "led me to consider the
increase of the power of gunpowder in various situations, and of its
use in the field. It is well known, that, after a few discharges,
a cannon becomes heated, and the range is much greater, as well
as the recoil. The charge of powder is, therefore, reduced about
one-quarter, to produce the original effect. As I have not heard or
seen any explanation of this fact, I shall take this opportunity of
mentioning, that it appears to arise from the same cause as the first
explained, _viz_: the desiccation of the powder, &c."

M. Humboldt, (_Bulletin de la Société Philomatique_, floreal, an. 3)
it appears, suggested an improvement in mining, not by increasing
the force of gunpowder, but in the charging of it; to leave a space
occupied only by air, a fact well known to those who are accustomed
to this work, although not always adopted. He states the effect of
powder on a shell; that, if it be filled, it breaks only into two or
three pieces; but if only half filled, it is shattered into a great
number, which he attributes to the presence of air in the shell.

_Sec. XXXIII. Of Incendiary Bombs._

These are used in sieges, and on water. Ruggeri gives the preparation
of these bombs as follows, observing to melt the substances in the
order they are mentioned.

1. Three parts of sulphur;
2. One part of pitch;
3. Two parts of nitrate of potassa;
4. One part of mutton suet.

After melting these substances, and mixing them intimately, the
mixture is removed from the fire, and two pounds of gunpowder are
added, and thoroughly blended. It is again submitted to heat, and a
sufficient quantity of quick match, to cover a good sized marron,
is immersed. The marron is furnished with a fuse. The composition
hardens on the match. The match is employed as before described.
Water does not extinguish the fire, produced by the combustion of
this composition. See _Carcasses_ and _Fire-Balls_.

_Sec. XXXIV. Of Murdering Marrons._

Marrons, which take this name, are those, whose effect is different
from the incendiary bomb. The latter is calculated to set fire to
houses, &c. while the former is designed to destroy the lives of
persons.

To make a murdering marron, we prepare, in the usual manner, a
cylindrical case, and fill it with gunpowder, and then wrap round
it, a quantity of pack-thread. In winding on the thread, care must
be taken to cross it in the manner mentioned in a former article. It
is then finished by coating it with a mixture of glue and wax, or,
in preference, pitch. This prevents the thread from unwrapping, and
renders the case firm and less liable to break. A hole is then made
in its side to the powder, in which we insert a piece of quick-match,
to communicate fire to the contents of the case. A small fuse,
similar to that of a bomb fuse, but shorter, and made of pasteboard,
is also used; and, after it is fixed to the marron, musket balls,
previously pierced with holes, are nailed round the marron, the nails
passing through the balls into the case. After thus fixing as many
balls as the surface of the case will admit, we cover them with a
composition made of three parts of glue and one part of wax. When
this coating is dry, a hemispherical case is adapted. This case is a
small _sack_ of paper, made round, and filled with gunpowder. It is
placed at the bottom of the marron, and secured there with paper and
glue. The match is conveyed to the orifice of the fuse of the marron;
and, in short, a communication is so made from the one to the other,
that, at a given time, the fire passes by means of the fuse to the
marron, which then explodes, and throws the balls, with which it is
furnished, in every direction.

Shells, made by uniting two hemispheres, containing powder, and
furnished with balls and a fuse, are also a destructive weapon of the
same character.

_Sec. XXXV. Of Incendiary Rope._

We have mentioned, under the head of _Tourteaux_, or tarred links and
fascines, the compositions made use of for these preparations. The
composition for incendiary rope is as follows:

Sulphur 12 parts
Saltpetre 6 ----
Rosin 2 ----
Camphor 2 ----
Meal-powder 4 ----
Grained powder 2 ----

The rosin, sulphur, camphor, and saltpetre are melted, and mixed
thoroughly together, and the kettle, which contains them, is removed
from the fire; the gunpowder is then added, and intimately blended.

The mixture is again heated, and the rope is then immersed in it,
and suffered to remain until it has imbibed sufficiently. It is then
taken out, and allowed to cool.

After this operation, we melt, in a separate kettle, the following
substances:

Rosin 4 parts.
Pitch (or tar) 4 ----
Mutton suet 2 ----

When they are melted, and mixed, the rope previously prepared as
above, is thrown into the mixture, and then removed and hung up.

After this second process, we make, in an earthen vessel, a priming
mixture, in which the rope is sometimes immersed, or such parts of
it, as are to take fire promptly. This priming paste is composed of,

Meal-powder 4 parts.
Saltpetre 4 ----
Sulphur 2 ----
Spirit of wine, (or brandy), a sufficient quantity.
Gum arabic ½ ----

Incendiary rope is used more generally in the form of a ball, which
is enclosed in a sack, and fired out of a common mortar. It was
invented by an officer at Toulon. See _Carcasses_.

_Sec. XXXVI. Of Balloons of Grenades, of Bombs, and of Flints or
Stone._

Balloons of this kind are cases, or sacks, made sufficiently large,
containing powder, and enclosing grenades, shells, and stones.

The balloon of grenades holds twelve charged grenades, containing
different quantities of powder. They are finished like powder sacks,
and _corded_ with small cord, twine, or thread. The balloon of
flints, river stones, or small pebbles, is made by enclosing these
substances along with powder in a sack, as before stated. These
balloons are employed for the defence of works, &c. See _Powder
Sacks_.

The _Ballon à Bombes_, of the French, is the same. It is a bag,
in which are placed _beds_ of smaller bombs, that are charged and
interlaid with gunpowder. The bag is put into another covering, that
is pitched, with the neck closely tied up with pack thread, in which
a fuse is fixed, as in ordinary bombs. The English say, that Colonel
Shrapnel's invention of the spherical case shot, is of a superior
kind. We purpose, therefore, to notice them in the following section.

_Sec. XXXVII. Of Spherical Case-Shot._

Ordinary case shot is a tin case or cannister, filled with iron
balls, so as to make up the weight of the shot. The balls are seldom
less than 1-1/4 oz, in weight. Little effect is to be expected from
firing case shot beyond 300 yards, from the very great divergency
of the balls. The following summary of the effects and advantages
of this species of shot, which, as invented by Col. Shrapnel, is
called the Shrapnel shell, will be sufficient for our purpose. It is
extracted from a book lately published.

1st. The whole charge takes effect on the enemy at any distance. By
the present mode of firing, the greatest part of the charge disperses
as soon as it leaves the muzzle of the gun, and cannot be directed.

2nd. Grape, or case shot, may be fired with effect equally close
and collected, to any distance within the range of the piece; and
the artillery need not advance within musket shot of the enemy, to
make use of this kind of fire with its full effect, and are not so
subject to have their guns charged either by cavalry or infantry.

3d. It requires less precision and exactness, to point a piece of
ordnance charged with spherical case shot than with round shot;
because case shot is a wide and dispersed fire, and the difficulty in
elevation consequently less.

4th. Its comparative destruction with that of round shot will be,
generally, as the number of the shot within the shells to one; that
is to say, a three pounder, twenty-two to one in its favour; a six
pounder, fifty to one, &c.; in which calculation is not enumerated
any effect from the splinters of the shell.

5th. Small balls cannot be projected to very considerable distances,
unless enclosed in heavy spherical cases, which, from their form and
weight, are not much influenced by the resistance of the air, or
diverted from their direction.

6th. The explosion of the shell makes no change in the direction of
the shot within; they consequently complete the shell's track, or
curve, which has sometimes been observed to be 400 yards.

7th. From the unevenness of the ground, such as hillocks, banks,
fallow fields, &c. all shot which graze, most commonly lodge:
whereas, by using this shell, the whole charge will be carried over
these irregularities, and reach the object with its full contents of
balls.

_Sec. XXXVIII. Of the Fire-Rain, according to Casimir Siemienowicz._

The composition, which produces fire-rain, which we purpose to
notice in this place, is taken from the "_Artis Magnæ Artilleriæ_"
of Casimir Siemienowicz. He seems, however, to have taken it from a
German author.

The fire rain is an incendiary fire-work, and calculated, like other
incendiaries, for firing the houses of a besieged place or city,
which are covered with shingles, laths, stubble, or reeds. Besides
several other compositions, designated by artificers, that of
fire-rain was so called from its supposed resemblance to a shower of
rain.

To prepare this composition, the following method is used: We take
24 parts of sulphur, and melt in a copper, or iron pot, over live
coals without flame, and then throw in 16 parts of saltpetre, and
mix it with an iron spatula, to incorporate the whole. The pot is
now removed from the fire, and when the composition is become rather
cold, stir into it 8 parts of grained powder. The composition is
then poured on a marble slab, or metallic plate, where it is allowed
to cool. It is then broken into pieces of the size of a walnut,
which, when used, is interspersed with quick match, covered with
gunpowder, and put into shells or bombs.

These bombs are made in the same manner, as those, which are formed
in fire-works for exhibition.

Wood, covered with this composition, will burn in the same manner
as the shells. The globe of fire is also similar to those for
exhibition. The mortar is elevated at an angle of 45°, in order that
the globe may go to the greatest height, and the greatest range; for
the fall of the inflamed matter, which is dispersed in all directions
by the powder, is more or less vertical, and, in that state, lights
upon houses, &c. This effect, that of setting fire to one or more
houses, depends greatly on the accuracy of their discharge from the
mortar.

The following compositions are also used for the same purpose,
observing to follow the same manner of mixing the ingredients:

1. Sulphur 3 parts.
Saltpetre 1 ----
Meal-powder 1 ----
Iron filings ½ ----
Green Vitriol ½ ----

2. Sulphur 1 part.
Saltpetre 1 ----
Grained powder 1 ----

3. Sulphur 1 part.
Galbanum 4 ----
Saltpetre 4 ----
Grained powder 1 ----

4. Sulphur 5 parts.
Saltpetre 2 ----
Rosin 1 ----
Meal-powder 1 ----

These compositions may be used in the manner already described. Two
wooden hemispheres, filled with the preparation and joined together,
is the usual mode of forming a fire bomb. The bomb or globe is then
covered with strong canvass, and finished by dipping it, or smearing
it with melted pitch. Over this, two or three covers of canvass are
sometimes sewed. When the bomb is dry, we put it in a case, in the
same manner as directed for the murdering, and incendiary bombs. The
case is charged with fine meal-powder, &c.

The modern improvements, which are many, supersede the rain-fire.
Fire stone, for instance, is a more powerful preparation. The
incendiaries made with this composition, and the ordinary carcass,
are more effectual for this purpose. That the Greek fire was an
active composition, and produced very destructive effects on towns
and shipping, there can be no doubt; notwithstanding the invention of
gunpowder has completely changed the art of war, and superseded, as
we have shown in our articles on _gunpowder_ and _Greek fire_, the
use of the incendiary composition of the Greeks.

_Sec. XXXIX. Of the Effect of Mirrors in inflaming Bodies at a
Distance._

As this subject may be of some interest to the reader, at least in
relation to an important fact, that of the _concentration_ of the
calorific rays of the sun, which has had the effect of burning bodies
at some distance, we deem the following facts not irrelevant.

The effects of burning glasses, both by refraction and reflection,
are noticed by Empedocles and Euclid, who composed a treatise on
the ancient optics and catoptrics. It has been thought, that the
Romans had a method of lighting their sacred fire by some such means.
Aristophanes, in one of his comedies, introduces a person as making
use of a globe, filled with water, to cancel a bond that was against
him, by thus melting the wax of the seal. Plutarch, in his life of
Numa, says, that the instruments used to kindle fires, were metallic
dishes, which were placed opposite to the sun, and the combustible
matter in the centre, by which, it is probable, he meant the focus,
conceiving that to be at the centre of the mirror's concavity.

Father Kircher was the first, who thought of substituting, for a
concave mirror, several plane mirrors, so disposed, that the sun's
rays reflected at their surface might converge towards the same
point. He employed five only of these mirrors, which he so arranged,
that the concurrence of the rays should take place at a distance
of more than one hundred feet, and he found the heat there to be
scarcely supportable. "Now," says Kircher, "if five mirrors produce
so considerable an effect, what would a hundred or a thousand do,
arranged in the same manner? They would excite so violent a heat,
that it would set fire to every thing, and reduce all to ashes."

Orpheus compares his _jaspis_ to rock crystal, and says that
it kindles fire, and that he knew how to use rock crystal as a
burning glass. Diodorus calls some kinds of jasper transparent, and
sky-coloured. The jaspis, described in the Revelation of St. John
(_chapter_ xxi, verse 11, 18, 19,) may have been the same stone.

It is not our intention, however, to notice the history of mirrors,
from the time of Moses, (_Exodus_, chap. xxxviii, verse 8,) or of
Job, (_Job_, chap. xxxvii, verse 18) through different periods of
time, to the present day; as the reader may find an interesting
account on this head in Beckman, (_History of Inventions_, vol.
iii, p. 154); but to state in particular the celebrated experiment
of Archimedes, which has indeed astonished men of science, who have
lived since that period. There can be no doubt of the fact, if we
reflect for a moment, that some modern experiments have justified
the conclusion which has been drawn; and, therefore, that the solar
rays may be concentrated to such a degree, as to inflame bodies at
some distance off: and as the heat produced is much greater than that
of our hottest furnaces, incredible as it may appear, there can be
no question as to the effect, which may be produced by a system of
mirrors.

By means of burning mirrors, Archimedes burnt the Roman ships, which
were beseiging Syracuse, and reduced them to ashes.

Descartes, among others, discredited the story as fallacious; but
Kircher made many experiments, with a view of establishing its
credibility. He tried the effect of a number of plane mirrors,
and with five mirrors of the same size, placed in a frame, he
contrived to throw the rays reflected from them to the same spot,
at the distance of more than one hundred feet; and, by this means,
he produced such a degree of heat, as led him to conclude, that,
by increasing their number, he could have set fire to inflammable
substances at a greater distance. He likewise made a voyage to
Syracuse, in company with his pupil, Schottus, in order to examine
the place of the supposed transaction; and they were both of opinion,
that the galleys of Marcellus could not have been more than thirty
paces from Archimedes.[42]

Proclus is also said to have destroyed the navy of Vitalian,
beseiging Byzantium, near Constantinople, by means of burning glasses.

Among the moderns, the most remarkable burning mirrors have been
those of Magine; of Septala of Milan, which was nearly three and a
half feet in diameter, and which burnt at the distance of fifteen or
sixteen paces; of Vilette, and Tschirinhausen; the new complex one
of M. Buffon; that of Trudaine, and that of Parker. Tschirinhausen's
burning glass was between three and four feet in diameter, and its
focus was rendered more powerful by a second one.

It may not be improper to notice the construction, as well as the
effect of some of these mirrors. La Brocquire, a traveller of the
15th century, says, that, at Damascus, they made mirrors of steel
that magnify objects, and one of them, when exposed to the sun,
reflected the heat so strongly, as to set fire to a plank fifteen or
sixteen feet distant.

M. Buffon constructed a machine consisting of a number of mirrors,
by which he seems to have revived the secret of Archimedes, and to
have vindicated the credit of history in this point. The experiment
was first tried with twenty-four mirrors, which readily set on fire
a combustible matter prepared of pitch and tow, laid on a deal board
at a distance of sixty-six French feet. He then pursued the attempt,
and put together a kind of polyhedron, consisting of one hundred and
sixty-eight pieces of plane looking glass, each six inches square;
and by means of this, some boards of beech wood were set on fire at a
distance of one hundred and fifty feet, and a silver plate was melted
at the distance of sixty feet. This machine, in the next stage of its
improvement, contained 360 plane mirrors, each 8 inches long, and 6
broad, mounted on a frame 8 feet high, and 7 feet broad. With 12 of
these mirrors, light combustible matters were kindled at a distance
of 20 feet; with 45 of them, at the same distance, a large tin vessel
was melted; and with 117, a thin piece of silver. When the whole
machine was employed, all the metals were melted at the distance of
twenty-five, and even of forty feet. Wood was kindled in a clear
sky, at the distance of 210 feet. Mr. Buffon afterwards constructed
a machine, which contained four hundred mirrors, each six inches
square, with which he could melt lead and tin at the distance of 140
feet.

Mr. Parker, an eminent glass manufacturer, in Fleet street, London,
constructed the most powerful burning mirror ever made. He erected an
out building at the bottom of his garden for the purpose of carrying
on his operations. He succeeded in forming a most powerful burning
lens. Its diameter was three feet. Platinum, iron, steel, flint, &c.
were melted in a few seconds, on being exposed to its immense focus.
A diamond weighing thirty grains was reduced to six grains, in the
space of thirty minutes. It opened and foliated like the leaves of a
flower, and emitted whitish fumes, (carbonic acid gas;) when close
again, it bore a polish, and retained its form. Garnets, clay, &c.
soon melted.

Seven hundred guineas were subscribed to indemnify the inventor, it
having cost him seven hundred pounds. It was purchased, however, and
presented by lord Macartney to the Chinese government, and remains
now at Pekin.

M. Payard, (_Archives des Découvertes_, &c.) has invented a burning
mirror, consisting of several plane mirrors so arranged as to
concentrate the solar heat into a focus with great precision. The
arrangement, it may be proper to state, is different from that
heretofore used, and the effect is said to be very powerful.

A polygonal mirror, from a suggestion of the celebrated Buffon, was
erected in the Botanic Garden at Paris, in 1747, and had also a
very powerful effect. This mirror was composed of one hundred and
sixty-eight plates of tinned or silvered glass, capable of moving
in every direction and of being fixed at different degrees of
inclination, so that there could be given to the whole, a form more
or less concave, and the focus be thrown to different distances. This
mirror set fire to wood at two hundred feet, and fused metals at
forty-five feet.

As caloric, like light, follows the same laws with respect to
its motion, and as the angle of incidence is equal to the angle
of reflection, the radiation of heat, conducted after the manner
of Pictet's experiment, has not only occasioned the combustion
of gunpowder, but of other inflammable substances. But, for this
purpose, the mirrors must be large and extremely bright. That heat
radiates in all directions, and is reflected, and that the calorific
rays may thereby be concentrated, are facts which are now universally
admitted. The application of this principle, by using concave mirrors
sufficiently large, has, we are informed, produced the explosion of
gunpowder. They were placed about twelve feet apart. In the focus of
one a live coal was put, which was constantly blown with a double
bellows, and in the focus of the other some gunpowder. In all our
experiments with the ordinary reflectors, we could never produce
any thing like the heat necessary to inflame gunpowder. That the
principle is substantiated by experiment is evident; for the rays
of a heated body, or a substance which produces heat, as a lamp or
candle, placed in the focus of a concave mirror, are reflected in
parallel lines, and if another concave mirror be placed opposite to
it at some distance, the calorific rays will be thus intercepted and
reflected back in a focus. This _focus_, therefore, like the focus
of a burning glass, is the concentration of all the parallel rays of
heat.

_Sec. XL. Of Incendiary and Poisoned Arrows._

The bow is a very ancient weapon of offence, made of steel, wood,
horn, or other elastic substance, which, after being bent by means of
a string fastened to its two ends, in returning to its natural state,
throws out an arrow with great force. That the bow was a weapon of
offence among the nations of antiquity, the inhabitants of Asia and
Africa, and the Aborigines of this country, and that it was used in
Europe, before the invention or use of fire-arms, are facts, of which
we have abundant proof. Bows are much the same in all countries. It
has generally two inflections or bendings, between which, in the
place where the arrow is drawn, is a right line. The Grecian bow
was adorned with gold or silver. The Scythian bow was distinguished
from those of the Grecians and other nations, by its incurvation,
which was so great, as to form a half moon, or semi-circle. The
Persian bows were made of reed. The Indians used the same material,
as well for their bows as their arrows. The Lycian bows were made of
the cornel tree; and those of the Ethiopians, which surpassed all
others in magnitude, were made of the palm tree. The Romans, although
they did not admit bows in the infancy of their republic; yet they
considered them as hostile weapons. They employed auxiliary archers
in all their wars. The Amazonians, as well as the primitive Grecians,
in drawing their bow, did not pull back their hand towards their
right ear, according to the fashion of the ancient Persians, and of
modern ages; but, placing their bow directly before them, returned
their hand upon their right breast.

While noticing this subject, we may also observe, that Louis XI first
abolished the use of bows in France, introducing, in their place, the
halberd, pike, and broadsword. The long bow was much in use by the
English archers, and many laws were passed encouraging its use. In
the time of Henry VIII, the parliament complained of the disuse of
long bows.

The bow is now laid aside altogether as a war weapon. The arrows,
made use of, were armed with barbed iron, and, among the aborigines
of this and other countries, with a stone, formed in a particular
manner, many of which are picked up in this country. We have found
them at West Point. The natives were in the habit of poisoning their
arrows, by using a particular composition, not known; the effect of
which, however, when the arrow penetrated into the flesh, is always
destructive.

Roggewein, (_Voyage for the Discovery of Southern Lands_) speaking
of Batavia, observes, that, at this place, there are some of the
Macassars, so famous for their little poisoned arrows, which they
blow through a trunk. This poison is the juice of a tree, that grows
in Macassar, and in the Bougie islands. They dip the points of their
arrows in this juice, and then let them dry. The wound they give is
mortal.

The natives of Ceylon are very dexterous with the bow and arrow; so
also are the Hottentots, according to Kolben, in his _Voyage to the
Cape of Good Hope_. A Hottentot arrow consists of a small tapering
stick or cane, of about a foot and a half in length, pointed with a
small thin piece of iron bearded, and joined to the stick or cane
by a barrel. Their bows are made of olive, or iron wood, and the
strings, of the sinews and entrails of beasts. When they attack a
lion, tiger, or leopard, which they do with wonderful resolution and
dexterity, they employ slings (_hassagayes_) and arrows, which for
that purpose are usually poisoned.

Ellis (_Voyage for the Discovery of a North-West Passage_) speaks of
the bows and arrows of the Eskimaux Indians, and the facility with
which they use them, but not of poisoned arrows. Moore, (_Travels
into the interior of Africa_) observes, that a native took him to
his house, and showed him a great number of arrows, daubed over with
a black mixture, said to be so venomous, that, if the arrow did
but draw blood, it would be mortal, unless the person who made the
mixture had a mind to cure it. For the man observed to him, that
there were no poisonous herbs, whose effects might not be prevented
by the application of other herbs.

Poisoned arrows, according to various historians, were used in the
remotest periods of antiquity. The mode of treating wounds in the
twelfth century, by using membrane like the present gold-beaters'
skin, may be mentioned in relation to this circumstance. The Emperor,
John Commenus, accidentally wounded himself in the hand with a
poisoned arrow, while hunting, and applied a piece of skin to the
wound. The emperor, however, died in consequence of the wound, after
it had become inflamed under the pellicle; which, in large wounds,
and when the skin is suffered to remain too long, is commonly the
case, though the poison alone we are informed, would have been a
sufficient cause of death. Other instances are also mentioned of
death being occasioned by the poisoned arrow.

On the subject of poisoned arrows, the following outline is given on
the authority of the author of the _Dictionnaire de l'Industrie_,
vol. 3, p. 50.

The juice of the _Mancenilier_, or the _Lianes des Marais_, called
in Guyanne _Curare_, is employed by some savages. The Arabs use the
juice of a milky shrub, which they name _chark_, and called by the
Persians _gulbut samour_. Indian arrows are said to be poisoned with
the venom of serpents. The islanders of Java rub their darts with the
blood and venom of the lizard _Gecko_, which they kill by whipping it
to death. The needles of the Macassars, they poison with the juice of
a tree, which is said to belong to the _ahouai_ of America. At Ceylon
they extract the venomous matter from the _Nerium_, or _laurel rose_.
The ancient Gauls are said by M. Paw to have poisoned their arms with
the juice of the _Caprisiguier_. In some cantons of the Pyrenees and
Alps, they express the juice of the roots of the Aconitum, (thora),
which they put on weapons.

M. Charles Coquebert, in a memoir read to the Philomatic Society, in
1798, observes, that the ancient European inhabitants employed three
plants to poison their arrows; namely, _Veratrum album_, _Helleborus
viridis_, and _Aconitum Lysocitonum_.

There have been obtained from the Society Islands some poisoned
arrows, and a pot of the composition, in which they are dipped. It
has the appearance of a black fluid extract, and seems to be an
infusion or decoction of some plants, probably mixed with other
substances.

With respect to the poisons obtained from the animal kingdom, they
are principally liquid juices. Fontana, in particular, has paid
attention to this subject. The poison of the viper, which is
contained in two small vesicles of the mouth, when the animal bites,
is forced, through the fangs, into the wound. If the vesicles be
extracted, or the liquor prevented from flowing into the wound, the
bite is harmless. Sharp instruments, as arrows, when they penetrate
the skin, being covered with the poison, will have the same effect.
Fontana made a set of experiments on the dry poison of the viper,
and a similar set on gum arabic, and obtained the same results!
Small birds and quadrupeds die immediately, when they are bitten by
a viper; but to a man, the bite is not always fatal. The experiments
and observations of Francini, (_Abridg. Phil. Trans._ ii, 8,) Mead,
(_On Poisons_, p. 35,) Tyson, (_Phil. Trans._ vol. xii,) Fontana,
Redi, Russel, the late Dr. Ramsay, of Charleston, (_Phil. Mag._ xvii,
125,) and Dr. B. S. Barton, (_Amer. Phil. Trans._ vol. ii, p. 100,)
furnish an abundance of facts on the venom of the viper, and some on
the antidotes to the bite. Dr. F. G. Gren, late professor at Halle,
in Saxony, (_Principles of Modern Chemistry_, ii, p. 47), observes,
in speaking of the experiments of Fontana, as the poison of the viper
exhibits all the characteristic properties of gum, whether the gum
be merely the vehicle of a peculiar venomous substance, which, upon
investigation, escapes the notice of the senses? or whether this
action upon living bodies, so different from its usual nature, be
imparted to the gum, merely by a change in the proportions of its
radicals, so slight as to be unobservable in its chemical analysis?

Mr. Misson (_Travels through Germany and Italy_) observes, that,
at the arsenal at Venice, he saw some pocket cross bows, and steel
arrows, with which the late lord of Padua used to kill such as passed
by, without their knowing from whence they received their wounds.

Arrows were sometimes employed by the Grecians, for conveying their
Greek fire. It seems, according to Gibbon, (_History of the Decline
and Fall of the Roman Empire_, vol. vii, 284), that, among the
different means of discharging it, that with the bow and arrow was
one. For this purpose, flax or tow was dipped in the composition,
and wrapped round the arrow, which was discharged the moment it was
inflamed.

The Indians, and Africans in particular, have been very ingenious in
poisoning several kinds of warlike instruments. The blades of swords,
the barbs of arrows, balls, &c. they have prepared in such a way, as
to be extremely poisonous.[43] See _Poisoned Ball_.

With respect to incendiary arrows, it will be sufficient to remark,
that the barb, for this purpose, was furnished with a composition,
which, when inflamed, was projected by the bow to the spot designed
to be set on fire. They were not much employed, and at the present
day, are entirely out of use. Tow, for instance, previously prepared
with pitch, meal-powder, and turpentine, or a composition equally
combustible, when wrapped round the head of an arrow, and thrown
at the moment of its inflammation, would, in many cases, set fire
to buildings. But, as the present system of employing incendiary
fire-works, presents advantages decidedly in its favour, it is hardly
probable, that the bow and arrow will ever be employed by civilized
nations for that purpose. The ancient _catapulta_ was particularly
calculated for throwing incendiary compositions.

The catapulta was an engine, contrived for throwing arrows, darts,
and stones, upon the enemy. Their power was so great, that they would
project a stone of a hundred weight with an almost incredible force.
Josephus, in noticing this machine, says, that the stones thrown
out of it, beat down the battlements, knocked off the angles of the
towers, and had a force sufficient to level a deep file of soldiers.

_Sec. XLI. Of Pyrotechnical Sponge._

This name is applied to the German _black match_, or tinder, used
chiefly to receive the file from flint and steel. We have, on a
former occasion, noticed the preparation of the substance called
spunk; namely, by immersing the fungus in a solution of saltpetre,
and then drying it.

There are various species of agaric. The mushroom is a genus
belonging to the order Fungi, and the _boletus igniarius_, spunk, or
touch-wood, called also female agaric, is employed, not only as a
match, but as a styptic. The fungous excrescences, which grow upon
old oaks, ash trees, firs, &c. are all used for the same purpose. The
Germans take the soft inner substance in preference to the hard, and
after beating with a hammer to render it still softer, they boil it
in ley, then dry it, and boil it again, in a solution of nitrate of
potassa, and finally dry it in an oven for use.

The _amadou_ of the French, is the same as our spunk, or
pyrotechnical sponge. It is always made, like the latter, from
various kinds of agaric, which constitute the spongy excrescence of
trees. The French prepare it for use in the manner before stated.
They prepare _amadou_, also, by soaking blue paper in a solution of
nitre. They sometimes employ it in the state of tinder, and, for this
purpose, burn it to a coal.

In the East Indies, there is a white spongy plant, which, when
reduced to a kind of charcoal, furnishes a very good tinder.

Spunk, or pyrotechnical sponge, is generally made in Germany.

In the preparation of ordinary _tinder_, the best mode of carbonizing
the old linen, instead of burning and then smothering the flame, is
to char the rags in close iron vessels. It may be made more quick by
soaking it in a solution of nitre, and then drying it.

Dry turf, or peat, is susceptible of inflammation by the spark,
and, if previously soaked in a solution of nitre, the effect,
we are told, is much the same as with spunk. Professor Beckman
(_History of Inventions_, i, p. 333), remarks, that a spark falling
accidentally on a turf moor, during a dry summer, often sets it on
fire; and the conflagration it occasions, often lasts so long, that
it cannot escape notice. Of the earth taking fire in this manner,
there are many instances to be found in the ancients. One of the
most remarkable, is that mentioned by Tacitus, (_Annal._, lib. xiii,
cap. 57), who relates, that not long after the building of the city
of Cologne, the neighbouring land took fire, and burned in such a
manner, that the corn, villages, and every production of the fields,
were destroyed by the flames, which advanced even to the walls of the
city. This was certainly a morass set on fire.

Gmelin (_Travels in Russia_, 1768-69, vol. i, p. 22) speaks of a
morass in Siberia, where a village was erected, which, on account of
its situation, the inhabitants deserted. This morass was set on fire,
and when he was there, had been burning for more than six months; and
being very inflammable, produced much devastation.

Turf, which consists of a congeries of vegetable roots or fibres,
partly in a dry and decomposed state, or partly carbonized, when
separated from earthy matter, and treated in the same manner as the
medullary excrescence of wood, may be advantageously employed in like
manner; but it is to be remarked, that for this purpose, the small
and more friable, and consequently the more decomposed part, should
be preferred. That turf, or peat, has been used for fuel, from time
immemorial, there can be no doubt; since it is furnished in some
countries very abundantly, and its inflammability has been long known.

_Sec. XLII. Of Extinguishing Flame with Fired Gunpowder._

The different methods for extinguishing fire in chimnies, by using
salt, sulphur, &c. to _smother_ the flame, as it is called, depend
on one principle, that of producing either a gas or vapour, which
supplies the place of atmospheric air, and as it is a non-supporter
of combustion, extinguishes the flame. Carbonic acid gas would
have the same effect as the sulphurous acid gas, produced by the
combustion of sulphur, or the vapour of salt.

So long, however, as the air is permitted to have a draught, the
fire will continue to burn; and hence, without making any remarks on
the bursting of chimnies, by closing all the avenues, by which the
air enters, as the fire must exert a lateral pressure, this plan is
generally adopted.

It has been suggested, and in fact the suggestion is by no means new,
that the _smoke_ of fired gunpowder would extinguish flame. Some
recommend firing a pistol up a chimney for this purpose, and others
again, throwing gunpowder into the fire.

In the _Dictionnaire de l'Industrie_, iii, p. 31, I find some remarks
on this subject. Besides the use of gunpowder, the vapour of water
is recommended; but having some objections, among which, that of
accelerating the current of air in particular, it is laid aside.
Intercepting the passage of air seems to be preferred.

It appears, that the person, who first suggested the use of gunpowder
for this purpose, was a Zachariah Greyl, of Augsburgh, in 1720.

The effect was attributed to the _vapour_ of the gunpowder destroying
the elasticity of the air; and the same effect is said to take place
when the vapour of sulphur, or of volatile acids, is employed. It
is hardly necessary to add, that this conclusion, of the diminution
of the elasticity of the air, on which depends its fitness for
combustion, (according to the theory then advanced), is altogether
hypothetical; and the cause of the extinction of the flame, must be
sought for in the substances themselves, producing an atmosphere,
which is decidedly a non-supporter of combustion.

The _Journal de Paris for_ 1785, and the _Affiches de Province_ of
the same year, recommend the use of brimstone. In the same work,
page 454, it is said, that marine salt is employed with success for
the extinguishing of fires; and that, when a certain quantity is
thrown upon the fire, it evaporates in an instant, and displaces,
by its _fumes_, the atmospheric air. In 1723, M. Hoffer invented
his machine; and in 1781, M. Cadet de Vaux made some experiments
before Leroy, Lavoisier, and Macquer, on the means of rendering
bodies incombustible by saline substances, and different modes of
extinguishing flame.

In 1722, the Germans announced, that, by means of a certain quantity
of gunpowder, flame at all times might be extinguished. The secret,
for such it was then considered, has been revived; for the same
plan has lately been recommended by a modern writer. M. de Reaumur
communicated to the French academy, an account of this contrivance,
by which it appears, that the machine was a large box, or cask, that
contained a large quantity of water; in the centre of which, was
placed a case of sheet tin, containing some pounds of cannon powder.
To this was attached a fuse. When it was inflamed, the gunpowder
would burst the vessel, and disperse the water in every direction.
See the _Journal des Savants_, 1725, p. 671.

In the _Dictionnaire de l'Industrie_, a prompt and certain method is
recommended for cleaning the tunnel of chimnies. This is rather a
novel plan. Of its efficacy we know nothing. It consists in taking a
powder, composed of three parts of saltpetre, two parts of salt of
tartar, and one part of flowers of sulphur, (or fulminating powder),
and exploding it on a shovel up the chimney. The explosion indeed
may detach the loose pieces of soot; but it cannot remove the harder
crust, and besides, it would endanger the chimney taking fire.

We know that various contrivances have been used for the same
purpose; and of the chimney cleansing machines, calculated to
diminish the number of infant victims of a filthy and disgusting
operation, that of Mr. Smart appears to possess every advantage,
which (or a plan similar to it) is now in use in our cities. A
description of this machine, and another by Hornblower, are given
in Gregory's _Mechanics_, vol. ii, p. 138. The invention of Mr.
Hornblower consists of a vessel, into which air is condensed, that
communicates with a tube, charged with small gravel, which being
blown up the chimney, brings down the soot.

_Sec. XLIII. Of the Inflammable Dart._

This dart is made in the following manner. We take a common rocket
case, of one inch exterior diameter, and charge it solid with the
ordinary rocket composition. Some use one spoonful of earth, and
three spoonfuls of the composition for fire lances, piercing the
case, and attaching a quick match. This, however, appears altogether
unnecessary, as the rocket composition is sufficient for the purpose.
The match, in either case, is fixed in the end to set it off. To the
end of the case is attached a dart, made of iron, and very sharp.
This dart is secured in the head, in such a manner as to be kept
firm. A stick is then lashed to the case in the usual way. It may be
sent in the direction required. It appears, however, that, although
it is calculated to be thrown on an enemy, it has not been much used;
nor can it be considered an active weapon, compared with others,
employed for similar purposes. One use for which it is recommended,
is for the defence of buildings.

_Sec. XLIV. Of the Firebrand._

The _boute-feu_ of the French, which we have translated into
firebrand, as the most appropriate term in the present instance,
is used as an incendiary, and is nothing more than a long stick,
furnished at one of its ends with two iron prongs, with sometimes the
figure of a dragon's head, on which is rolled thick rope, previously
prepared in the same manner as tourteaux. One end of this rope passes
between the iron prongs. The boute-feu is calculated to set fire to
buildings, &c. after the retreat of an enemy. It is only a convenient
and expeditious mode of communicating fire. One end of the stick is
pointed, and usually covered with iron, so as to stick in the ground.

_Sec. XLV. Of the Fire Flask._

The fire flask, or fire bottle, is a bottle, either square or round,
and charged with grain-powder, mixed with fire-stone, which is
introduced and compressed with a stick. The bottle is then covered
with a cloth, sewed on it, which is coated with pitch. The mouth is
secured with parchment. When used, a match is inserted, and inflamed.
It is then thrown by the hand.

_Sec. XLVI. Of the Trompe-Route._

The _trompe-route_ of the French is a light made use of at sea, to
deceive the enemy. It is nothing more than a common fire lance, one
inch in diameter, and twelve inches long, fixed in the centre of a
round plank, which, when lighted, is let down upon the water. As it
floats from the ship, the lights of the latter being darkened, the
enemy, in pursuit, will follow the light, and by this means the ship
escapes.

_Sec. XLVII. Of Fire-Pots for Ramparts._

Rampart fire-pots are used, when an enemy approaches a work. They are
furnished with grain-powder, and charged grenades without fuses, and
sometimes also with fire stone. The pots are ordinary potters' ware,
and, when they contain the ingredients, are covered with parchment.
A match passes through the opening of the pot, and when used, is
inflamed with a port-fire. The following composition is also used for
rampart pots.

_Composition for Rampart Fire-Pots._

Saltpetre, 12 parts.
Meal-powder, 12 ----
Sulphur, 4 ----
Antimony, 4 ----

These ingredients are mixed in a mortar with the oil of petroleum,
or, if this cannot be had, good spermaceti oil, and made into a thick
paste, about the consistence of dough, and then rolled into balls.
The pots generally hold two rows of these balls, distributing through
them grained powder. They are then finished by using fire stone
composition, beaten into pieces, and mixed with an equal quantity
of grained powder, and covered with meal-powder to facilitate the
inflammation.

The pots are covered over with parchment, as in the former case.
It is doubtful, whether fire pots, prepared in this way, have any
advantages over those, made in the manner first described.

As to the shape of fire-pots, some are cylindrical, and others of
the common figure. Sometimes they are furnished with an iron hoop,
with a hook of iron, by which they are suspended. They are used, when
equipped in that way, more for sea service, as a defence against
small boats. They are hung over the side of the vessel, so as to come
in contact with the boats. When designed in particular for that use,
they are charged with the following composition:

_Composition for Fire-Pots, for sea service._

Grained powder, 6 lbs.
Meal-powder, 2 --
Saltpetre, 1 --
Sulphur, ½ --
Charcoal, 10 oz.

With this composition, grenades are used, which are put into the pot
with powder, fire-stone, &c. and a match is fixed as before mentioned.

We are told, that fire-pots, prepared in this manner, are a
defensive, as well as a dangerous weapon, and that a vessel in the
Indian seas was actually saved by them, when attacked by pirates.
It appears, that she endeavoured to escape from her pursuers, and
finding it in vain, the crew thought of making, and employing
fire-pots, for their defence; as the number of the pirates was
greater than their own crew. The effect was, that, not expecting that
kind of reception, they were obliged to abandon their enterprize.

There is an incendiary fire-pot, which differs from that used in
fire-works for exhibition, by being made of copper and very stout. It
is charged with pieces of fire-stone, previously rolled in a paste
of meal-powder and brandy. A charge of powder is put in the pot, and
quick-match is fixed, which must be sufficiently long to hang over
the pot, and then the fire-stone is thrown in. When the match is
inflamed, the powder takes fire, and disperses the fire-stone. The
better plan is to have a communication to the powder below, as in
the pots of ordnance, or mortars for throwing fire-balloons. We see
no particular advantage to be derived from the use of this pot; as a
carcass or fire-ball, thrown out of a mortar, will do more execution,
and at a greater distance than any of these contrivances. The carcass
rocket, however, may be an exception, if we believe the account we
have of it. As an incendiary, the fire-stone, put in a shell with
powder, is more effectual than the fire-pot, we have just described.

_Sec. XLVIII. Of Inflammable Balls._

Count Rumford (_Bibliothèque Physico-Economique_, 1812) has invented
a composition, which is very inflammable, and, as it is used in
balls, is for that reason so called. Equal parts of clay, pitcoal,
and charcoal of wood, are mixed together, (having previously reduced
them to powder), and made into a consistence with water fit to roll
into balls. These balls are then dried for use.

They may be rendered more inflammable, by soaking them in a strong
solution of saltpetre.

Count Rumford, when he recommended the use of clay with coal, was
aware, that, in the combustion of coal, a considerable part of the
heat was lost; whereas, although clay is incombustible, a greater
part of this heat is retained by the clay, and given out gradually.

The inflammable ball may be considered more in the character of an
economical fuel than in any other.

The only inconvenience attending these balls is, that, when prepared
without nitre, which must add to the expense, they do not readily
inflame; and, therefore, a fire must first be kindled, before they
are used.

While noticing the use of clay in this manner, we may remark, that
the _economical brick_, as it is called, is made nearly in the same
way.

Two parts of clay, separated from stones, are mixed with one part
of pitcoal. After the fire is kindled, the coal burns in the same
manner, and the clay bakes.

Another composition is given in the _Bibliothèque
Physico-Economique_, for March, 1812. It is composed of potters'
clay, cow dung, street dirt, saw-dust of wood, turf, horse dung,
straw, and tan. Besides these, pitch, tar, oils, and other
combustible substances, are occasionally used, either with the above,
or mixed with pitcoal in powder.

Observations on this preparation may be seen in the work quoted, or
in the _Archives des Découvertes_, v, p. 137.

_Sec. XLIX. Of Pauly's Inflammable Powder._

We mentioned, in a note to the article on guns, that M. Pauly had
invented a musket, or fowling piece, which was discharged by
percussion, instead of flint and steel, by using a priming powder
made of chlorate of potassa.

It may be proper, however, to state, that the Rev. Dr. Forsyth made
use of a similar powder, and for the same purpose, many years ago, of
which we have already spoken. M. Thenard also has given a formula for
a preparation of a similar powder.

A description of M. Pauly's improvement may be seen in the _Archives
des Découvertes_, for 1812, p. 158, and in that of 1814, p. 174,
where the composition of the powder is noticed; and also in the
_Bulletin de la Société d'Encouragement_, for 1814.

This powder is composed as follows:

Chlorate, or hyperoxymuriate of potassa 8 oz.
Flowers of sulphur 3 --
Charcoal of light wood 2 --

They are mixed together with Cologne water, or in its place with
brandy, to which a small quantity of the solution of gum arabic is
added.

The ingredients must be made as fine as possible, and intimately
blended together.

This powder may be inflamed by a hammer, or by the condensation of
air in a piston, a mode recommended by Pauly.

We have seen a fowling-piece, constructed according to M. Pauly's
plan, and also the priming powder used.

_Sec. L. Of Extemporaneous Fire._

There are several preparations, which have the effect of producing
fire either by friction, or chemical action. Some of these
preparations, we have noticed. The causes of spontaneous combustion
may be referred to chemical decomposition, and the change of
quiescent into distributable heat. We remarked, that a mixture of
chlorate of potassa and sugar is inflamed, when brought in contact
with sulphuric acid; that, in the slaking of quicklime, the heat
is sufficient to inflame oils; that pyrites by decomposition very
frequently sets fire to combustible bodies; that oil of turpentine is
inflamed by nitric acid; that pyrophorus, when exposed to the air,
takes fire, and also phosphorus by slight friction; and that, in all
cases of combustion, either friction, an increase of temperature, or
the action of some body, which is brought in contact, are necessary
to produce the effect.

Water, when added to some substances and preparations, will produce
fire. Thus potassium readily decomposes it, and the potassuretted
hydrogen gas, which is produced in flames. The same may be said of
phosphuret of lime and water; for the phosphuretted hydrogen gas
inflames, when it comes to the air.

On some occasions, these substances may be employed as incendiaries.

Hanzelet remarks, that the following composition will produce
inflammation with water.

_Extemporaneous Fire._

Linseed Oil 3 lbs.
Spirit of Turpentine 1 --
White of egg ¼ --
Quicklime 8 --

It is doubtful, however, whether this composition will have that
effect; although the heat produced by the slaking of quicklime is
very considerable, and, as we remarked, spontaneous combustion, in
several instances, has been referred to its agency. Lime, in the act
of slaking, absorbs, and chemically unites with, water, which becomes
solidified, converting it into a hydrate, whilst its latent caloric
is set at liberty. This is a process, which puts quiescent heat in
motion, to become distributable heat. See _Introduction_.

If the quantity of free caloric, thus generated, be sufficient, the
turpentine and oil will necessarily inflame.

We may add, therefore, that a rapid transition of caloric, from a
latent to a free state, as in combustion, is all that is required to
produce effects of this kind; and, in short, all cases of spontaneous
combustion may be accounted for on this principle; by considering
the cause, which acts in those instances so powerfully, and in some
instances instantaneously, and which changes caloric from a quiescent
to a distributable state.

Dr. Irvine refers all cases of combustion to a change in the capacity
of bodies for caloric; which depends on the nature of the products:
if they have a greater capacity, no flame ensues, and the caloric
remains more or less quiescent; if they possess a less capacity,
flame is the consequence. There are exceptions to this doctrine.

In the emission of caloric, Dr. Black supposes, that it is given out,
in consequence of the resulting attraction of the new compound for
caloric being less than that of its ingredients, when separate. M.
Curadou (_Journal de Physique_, 1809) observes, that, in preparing
the _artificial stone_, one-half of which is composed of water,
by mixing one part of sulphuric acid with two parts of clay, and
a sufficient quantity of water, a higher temperature is produced
than that of boiling water. In this instance, we find that, in the
formation of sulphate of alumina, which envelopes the silica, the
water is solidified, as in many other cases, and, while it forms a
solid substance, the caloric of fluidity is liberated. The heat,
he remarks, is sometimes so great as to set fire to inflammable
substances.

_Sec. LI. Of the Indian White Fire._

This preparation (_feu blanc Indien_ of the French) is described in
the _Archives des Découvertes_, &c. vol. ii, p. 300. It appears, that
it was kept secret in France, and was used by the French astronomers
for signals.

In 1807, M. de Zach published some account of it, in his
_Astronomical and Geographical correspondence_.

The case, in which the composition is put, is ten inches in diameter
and four in height; but may be of any size, according to the quantity
of the composition to be burnt, and the degree of light required. It
was seen 40 miles at sea. General Ray lighted, on the English coast,
a case of this fire, which was seen very distinctly on the French
coast.

_Composition of White Fire._

Saltpetre 24 parts.
Sulphur 7 ----
Red arsenic 2 ----

This powder lights without explosion, and illuminates with great
brilliancy. Care must be taken not to breathe the Arsenical vapours,
which are produced by the combustion.

A case of six inches in diameter, and six inches high, burns three
minutes. The light is said to injure the eyes.

The price of this powder is equal to that of ordinary gunpowder.

The match, which accompanies this preparation when it is sold, is
made in the following manner: Pulverize four parts of saltpetre, two
parts of gunpowder, two parts of charcoal, and one part of sulphur,
and pass them through a sieve. Provide then a number of paper cases,
made in the usual manner, or a roller, about the diameter of a quill,
and two feet in length, and charge with the composition.

This match, when used, is attached to a stick. It will resist the
action both of wind and rain.

An artificer of Marseilles proposes the following composition for
matches.

Sulphur 8 parts.
Saltpetre 4 ----
Gunpowder 2 ----

_Sec. LII. Of the Pyrophore of Defence._

An apparatus for defence, called the _Pyrophore_, was announced in
a French publication in 1815. It may be applied, according to the
author, in 24 hours for the defence of towns, roads, passages, and
defiles.

The pyrophore itself is a square box furnished with a lid, and
sufficiently large to contain fifty pounds of gunpowder. When it is
filled, and to be used, it is fixed with cords, or chains, in such a
manner as to be conveyed to a given point. The lid is furnished with
cross pieces, which open it when necessary.

At the sides of the box are rings, made very strong and fixed in
bolts, which go through the sides, and clenched. To each of these
rings, a cord or chain is attached, furnished at each end with a
_crotchet_.

This cord or chain runs upon two fixed pulleys, placed for instance,
at the two extremities of a battery, and is managed by artillerists.
The pyrophore is under cover. When it is conveyed to a certain place,
where a bar or grate is fixed, it is stopped, by the contrivance
before mentioned, the lid is raised, and the powder falls into a kind
of funnel or gutter, at the end of which the explosion is made, to
take effect.

It appears that the inventor had in view the conveyance of a given
quantity of powder to a particular place, and by carrying a light to
it by means of a cord, similarly fixed, to inflame it, when it had
arrived at its destination.

It is impossible to make a machine of this kind effective; for the
difficulty in arranging, and finally managing it, the enemy taking
means to guard against it, are certainly obstacles, and strong
objections to its use. Other means of defence, which we have pointed
out, are preferable; although we admit, that, in _some_ situations,
a contrivance of this sort might be advantageously used, where,
for instance, we wish to deposite a quantity of powder, to be in
readiness for the approach of an enemy, without exposing men to an
attack. What is more destructive than the thundering barrel, which
is furnished with grenades, &c. &c. if set off among the assailants?
See, for a minute account of this contrivance, the "_Pyrophore, ou
Moyen de defense générale_, par un garde national: 20 pages grand
in 8vo. avec un planche. _Paris Dondey Dupré_, 1815," and also the
_Archives des Découvertes_, tome 8. p. 281.

VOCABULARY

OF FRENCH TERMS, WHICH OCCUR IN THE WORK.

_Aigremore._ Pulverized charcoal, proper for fire-works.

_Aigrette._ An imitation in fire of the aigrette; like the aigrette
of glass.

_Ailerons._ They are used in making rockets.

_Amadou._ A kind of tinder made with agaric.

_Ame._ This is more particularly used to express the kind of work,
put in the head of a rocket. The term, however, is arbitrary.

_Amorce._ Priming: a paste of powder and spirit of wine.

_Arquer._ A name given to a particular shaped case.

_Artifice, feu d'._ Fire-works; artificial fire.

_Auget._ The wooden trough to contain the saucisson, which
communicates fire to a mine.

_Baguette._ A rammer, roller, former, &c.

_Baguette à charger._ Rammers or chargers, pierced with holes
in their length, more or less, to receive the piercer. They are
applicable to the charging of rockets, if they are to be driven
hollow; if not, solid rammers are employed.

_Baguette à feu._ Fougette; East Indian rocket. See page 529.

_Baguette à rouler._ A former, on which the pasteboard or paper is
rolled, in forming cases for rockets, port-fires, &c. &c.

_Baguette de fusée volante._ Rocket stick. A stick, attached to the
rocket, before it is set off.

_Baguette en massive._ Rods or rammers, which are not bored.

_Bague suspendue aux cendres d'un fil._ A ring suspended to the
ashes of a thread.

_Ballon._ Balloon; a bomb or shell, made of pasteboard, which is
thrown in the air by means of a mortar.

_Ballon à bombes._ A large globe, filled with bombs, grenades, &c.
fired by means of a fuse, and thrown into the works of the enemy.

_Ballon d'Artifice._ A bomb, or spherical case, containing sundry
compositions.

_Ballons d'air._ Air-Balloons.

_Ballons d'eau._ Water-Balloons.

_Battage._ The process of pounding, grinding, and mixing, with
water, the three substances, composing gunpowder, to reduce them
to a proper consistency. It is performed in wooden mortars, with
wooden pestles, furnished with a brass box to agitate the water.
The time, employed in the battage in France, is from 14 to 22 hours.

_Bateau-poisson._ A diving boat.

_Billot à charger._ A billot for charging; used occasionally in the
place of a mallet.

_Boîte._ A species of small mortar. It is used, also, to express
a piece of wood or pasteboard, used in the arrangement of some
fire-works.

_Bonnetage._ The covering of priming over a case, or fuse.

_Bouffées._ Literally puffs, or blasts: in Pyrotechny, a kind of
fire-works, used in theatres, to represent the flames, issuing from
gulfs, or the caves of Cyclops. They are also called Cornets, from
their resembling horns in their shape.

_Boute feu._ Lintstock.

_Bouton._ The extremity of the culot is sometimes so called.

_Brin._ Frame. The frame on which are placed or fixed, fire-pots,
saucissons, &c. Hence _pots de Brin_, &c.

_Carabé or Karabé._ Yellow amber.

_Carte de Moulage._ Means in general, the paper for cases.

_Chapiteau d'artifice._ Conical head of a rocket.

_Chasse._ Charge of grained powder for mortars, &c.

_Chevelure de feu._ A species of furniture for rockets, in the form
of serpents.

_Chelingues._ A marine term. A kind of flat bottomed boat, used on
the coast of Coromandel.

_Corde à feu._ Match rope. Slow match. A match to preserve a small
quantity of fire.

_Courantin._ A messenger, runner, or flying dragon; a rocket, that
flies along a rope or string. See page 345.

_Courantin simple._ A line-rocket. A rocket fixed on a cord,
stretched horizontally on which a rocket moves.

_Courantin double._ Two line-rockets.

_Courier pigeon._ Carrier pigeon. See page 490.

_Culot._ Bottom; the thickest part of a shell, opposite to the
eye; also called reinforcement. The round iron plate, fixed upon
the sabot, or shoe, for cannister shot, or at the bottom of the
cannister, to project the shot with more force:--The bottom, or
block, which supports the piercer and mould for charging rockets,
(see plate, fig. 1):--That part of a cannon cartridge, which
remains in the piece after firing.

_Camouflet._ A small fougasse, to act against the enemy's miners,
who are heard at work, to suffocate them and poison their branch.

_Dauphin._ A fire-work in water.

_Debonneter une fusée._ The paper cover, put over the priming of a
fuse.

_Eaux de cuite._ Literally, water of boiling. The strongest
lixivium obtained in extracting nitre from plaster rubbish. It must
mark more than five degrees of Baumé's areometer, and is called
water of boiling, on account of its being sufficiently strong, to
be immediately subjected to boiling, for further concentration.

_Eaux forte._ Lixivia from plaster rubbish, which mark between
three and five degrees of the areometer.

_Eaux faibles._ Lixivia from plaster rubbish, whose strength is
under three degrees of the areometer.

_Eclair, ou jet de flame._ Several fire-works are so called from
their effect.

_Eclatante._ A case charged with brilliant fire.

_Epoussetage._ The process of separating the dust from gunpowder;
also of separating mealed powder, from that which is not reduced.

_Eprouvette._ Gunpowder triers: an instrument for proving gunpowder.

_Etoile._ Star.

_Etoiles à pet._ Stars which explode.

_Entonnoir._ The crater or tunnel of a mine, as formed by its
explosion.

_Etoupille._ Quick match, leader, match of communication; cotton or
thread mixed in a paste, composed of meal-powder, spirits, and a
small portion of gum.

_Etrangler._ Strangling; choaking. The closing of a case, and tying
it.

_Fanaux de Mer._ Ship lights;--Beacons for vessels in the
night;--watch-lights.

_Feu blanc Indien._ Chinese fire.

_Feu brilliant._ A bright vivid fire. Thus the fire, produced by
steel and iron, in fire-works, is denominated a brilliant fire.

_Feu commun._ Common fire. A fire produced by the mixture of powder
and charcoal.

_Feu mort._ Dead light; dead fire. See page 485.

_Feux de Gouvernement._ State or public fire-works.

_Filagere._ The thread used for strangling.

_Flamboyante._ A species of rocket, which, from its effects in the
atmosphere, is called the comet.

_Foudres._ Thunderbolts, lightnings; in pyrotechny, the
preparations, used to imitate thunderbolts; thunder powder.

_Foudroyante._ A case or rocket, which imitates thunder: Fougette.
(See Baguette à feu.)

_Fougasse._ A small mine.

_Fougues._ Small rockets, without sticks.

_Fourneau._ Furnace. A mine. The chamber of a mine.

_Fusée._ Any sort of composition, put in a cylindrical case.
In English, however, the term fuse is confined to particular
compositions; as fuse for bombs, howitzes and grenades.

_Fusées chevelues._ Bearded rockets. See page 424.

_Fusées d'amorce._ Priming fuses.

_Fusées volantes._ Flying or sky-rockets.

_Garniture._ Garniture, furniture, embellishment, ornament: in
pyrotechny the small fire-works, such as stars, serpents, marrons,
&c. which are put into the pots of sky-rockets, into fire-pots, &c.
The petards with which the pots of incendiary rockets are charged.

_Gargousse._ Cartouch, cartridge. It more properly means the sack,
or bag for containing the charge of powder for a cannon, _when the
bag is made of paper or parchment_; but when it is made of serge,
it is called sachet. (See sachet.)

_Girandole._ Chandelier: in pyrotechny, two or more horizontal
wheels, placed above one another and turning upon the same vertical
axis. When of different sizes, these wheels resemble a chandelier;
hence the name.

_Girande._ A cluster, or assemblage, of several hundreds or
thousands of rockets, thrown up at the same time. Several clusters
may be arranged in different boxes, and fired separately with
regular intervals, or all at the same time. In either case, the
assemblage is called a Girande. It is also called _gerbe_. See
gerbe, and page 455.

_Gerbe._ Sheaf; a fire-jet case, charged with the composition for
brilliant or Chinese fire, which is thrown out in such a manner
as to represent a luminous sheaf. A group of fuses, or fire-jets,
fired at the same time, also bears this name: A Chinese tree.

_Grenage._ The graining of gunpowder.

_Glace Inflammable._ Inflammable ice.

_Lissage._ The glazing of gunpowder.

_Lardon._ This term generally signifies all those small fire-works,
which are sold in shops; such as serpents, squibs, crackers, &c.;
but, more strictly, it signifies the largest, and strongest kind of
serpents.

_Lance à feu._ Squib, fire-lance, or simply lance.

_Lance de feu._ A species of lance used by garrisons against
scaling parties.

_Lance à feu puant._ Stink-fire lances, used by miners.

_Lanterne._ Literally lantern; a copper spoon, or ladle, used
instead of cartridges for conveying the charge to the bottom of a
cannon. They were formerly used in all pieces, but at present only
in siege and garrison pieces.

_Larmes à feu._ Fire-tears, or drops; tears.

_Lianes des Marais._ A species of convolvulus; bind weed.

_Marquise._ Marchioness; a rocket having an interior diameter of
two-thirds of an inch. When it has the diameter of five-sixths of
an inch, it is called a double marquise.

_Machine Infernale._ Infernal machine.

_Mosaique._ Mosaic; the imitation of mosaic in fire-works.

_Meurtrières._ Literally Murderers: applied to those modifications
of any species of fire-work, which fit them for the destruction of
an enemy.

_Partement._ See fusée de partement.

_Partement, fusées de._ Sky-rockets, having an interior diameter of
half of an inch. When the diameter of the rocket is only one-third
of an inch, it is called _Petit Partement_.

_Paratonnerre._ Lightning rod.

_Patte d'oie._ A goose's foot: a kind of fire-works, so called from
their resemblance to a goose's foot:--A term in mining to signify
three small branches, which run out at the extremity of a gallery.

_Pots à feu._ Fire pots: they are thrown upon the enemy in the
attack or defence of places; but are not so much used as fire-balls
and carcasses: pot granado.

_Pots des Brins._ See page 364.

_Pots de Chasse._ See page 360.

_Pots des Saucissons._ The pots of saucissons.

_Pluie d'or._ Golden rain.

_Poudre d'or._ Gold powder.

_Porte feu._ Port-fire; also a leader.

_Pièce pyrique._ This name is generally given to all kinds of
fire-works; composed of fixed and turning pieces, which would
require a great number of words to describe separately; but it is
more particularly given to a kind of mechanical contrivance of
fixed and turning wheels, one of which communicates fire to the
other, and vice versa. See page 412.

_Ricochet._ A bound, leap, or skip, such as a flat piece of stone
makes, when thrown obliquely along the surface of a pond: The
bounds, which are made by balls, fired with small charges, and
under angles of little elevation, either upon land, or water:
Fire-works, which leap or roll on the ground.

_Roche à feu._ Fire-stone.

_Séchage._ The process of drying either gunpowder or fire-works.

_Saucisson._ Sausage: in pyrotechny, a sort of fuse or petard,
still larger than the lardon:--A cylindrical bag of powder to
convey fire to a mine:--A bundle of sticks, used in fortification.

_Soleil montant._ Rising sun.

_Sachet._ Satchel: the bag or sack of a cannon cartridge, when made
of serge.

_Tourteaux._ Links: see page 500.

_Tourteaux goudronnés._ Tarred links.

_Tourbillon._ Whirlwind, vortex: a table wheel.

_Tourbillon de feu._ A whirlwind of fire; fire-wheels, which rise
or fall in the air; also called rising or falling suns.

FOOTNOTES:

[1] We deem an outline of the nature and effects of caloric as, in
some respects, indispensably necessary; for caloric, it is to be
observed, is an agent, whose effects are recognised in every species
of fire-work.

[2] That the terms _hot and cold_ are relative, as to our feelings,
fact and observations abundantly prove. Dr. Fordyce (_Phil. Trans._
vol. 64 & 65) heated a room by stoves to two hundred and sixty
degrees of Fahrenheit's scale, and remained in it for some time
without great inconvenience. But different metallic substances, as
the lock of the door, his watch and keys lying on the table, could
not be touched without burning him: and although an egg became
hard, and his pulse beat one hundred and thirty-nine per minute,
yet a thermometer placed in his mouth was only two or three degrees
hotter than common. He perspired profusely. Jenning's steam bath
will heat the air in contact with the naked body from one hundred
to one hundred and twenty degrees, a _heat_ sufficient, as it is
in the aqueous vapour, resulting from the combustion of alcohol or
strong spirit, to induce a copious diaphoresis in less than half
an hour. Having tried this experiment in several cases, I can only
say, that I effected in the course of an hour, what, under ordinary
circumstances, would require twelve or twenty-four, viz. a _copious
perspiration_, and that too without the exhibition of sudorifics.
The practice is an old one not only among civilized nations, but
aborigines. It is nevertheless worthy of adoption.

Frozen mercury cannot be touched without experiencing a sensation
similar to that of an ignited body, although directly opposite to
heat.

[3] A writer of the last century remarks, that "he cannot possibly
admit the sun to possess the least manner of heat, but rather to
contain the capabilities of fire, like a stick, or a flint, though
with a faculty of expressing it, by its own action, which the others
have not. I imagine its beams not to be hot, in their rectilineal
direction, but productive of this effect, from reflection,
only. If the rays of the sun were fire, in the first instance,
those consequences would naturally follow, that our friend and
correspondent _Tria_ so well describes in his _Day of Judgment_, 'The
rivers were dried up, and liquid ore supplied their burning channels.
The clouds were turned to fire, and shot through the astonished sky.
The air was flame, and breathing was no more. The firmament was
melted down, and rained its sulphur o'er the prostrate globe, &c.'
The sun emanates light only, in the direct line, but owes its heat
to reflection. We feel it, therefore, more intensely, in a valley,
than on a hill. Why are the Alps and Pyrennees crowned with eternal
frosts, while the shepherds, with their flocks, are sheltering their
scorching heads from the heat of the sun, at the foot of them? Why do
the upper regions of the air shower down their hail and snow, to be
thawed and melted here below? Why shall a _lens_ of ice receive the
rays above, so coldly, and transmit them so intensely hot, beneath?
Why is it warmer, in summer, though the sun is farther off, than in
winter, when 'tis so much nearer to us? Because of our situation,
in regard to it, only. In the first case the rays are vertical, in
others lateral; and perpendicular reflections are stronger, than
oblique ones. We judge of fire above, from what we feel below, &c."

The summit of Ætna, notwithstanding the fire of the volcano, is
covered almost all the year with snow. Fazello, speaking of this
says, that "this region extends nearly twelve miles; and, even in
summer, is almost perpetually covered with snow, and extremely cold:
which is the more wonderful as the summit continually produces,
nourishes, and pours forth flames amid the ice and snow with which it
is enveloped." Solinus says, "Ætna, in a wonderful manner, exhibits
snows mixed with fires; and retains every appearance of the severest
winter, amid her vast conflagrations."

Silius Italicus, and Claudian, and Pindar, who lived 500 years before
the Christian era, bear testimony to the antiquity of this fact.

'Where burning Ætna, towering, threats the skies,
Mid flames and ice the lofty rocks arise,
The fire amid eternal winter glows,
And the warm ashes hide the hoary snows.'

_Silius Italicus_, from the Latin.

'Amid the fires accumulates the snow,
And frost remains where burning ashes glow;
O'er ice eternal sweep th' inactive flames,
And winter, spite of fire, the region claims.'

_Claudian_, from the Latin.

----'Snowy Ætna, nurse of endless frost,
The mighty prop of heaven.'

_Pindar_, from the Greek.

The height of Ætna is generally estimated at 11,000 feet above the
sea. In 1755, it issued out a torrent, not of mud, as was supposed,
but of snow and ice melted by the lava. The same thing happened at
the volcano of Cargarossa in South America.

The celebrated Herschel, (Phil. Trans. 1801, and Nich. Jour. 1.
13), in considering the construction of the sun, infers it to
be a habitable globe more magnificent than our earth, or other
planets, and that its lucid substance is not a liquid nor an
elastic fluid; but that it exists in the manner of luminous clouds,
swimming in the transparent atmosphere of the sun, or rather of
lucid decompositions taking place within that atmosphere. The
_Philosophical Transactions_, 1795, p. 72, also contains remarks on
this lucid matter. Having rejected the old terms of spots, nuclei,
penumbræ, and luculi, he has substituted those of openings, shallows,
ridges, nodules, corrugations, indentations, and pores. The openings
are places where the luminous solar clouds are removed, which he
thinks are produced by a wind or gas from the sun's body. Shallows
are depressions below the luminous clouds, and are caused by the
propelling gas, which produces the openings. They are tufted like
masses of clouds. Ridges are elevations of the luminous clouds. The
length of one of the longest was found to be 75,000 miles. They
generally surround the openings. Herschel thinks it probable, from
appearances, that the luminous matter is disturbed at top by the
transparent elastic fluid, which issues from the openings. Nodules
are small elevations of the luminous matter. Corrugations are smaller
elevations and depressions of the same matter. Indentations are the
dark places of corrugations. That they are not much depressed, is
deduced from their visibility near the margin of the sun. They are
of the same nature as shallows, and of different sizes. Pores are
the low places of indentations. The doctor is of opinion, that the
phenomena before described could not appear, if the shining matter
were a liquid; because, by the laws of hydrostatics, the openings,
shallows, indentations, and pores would be filled up. Still less
could these phenomena exist with the supposition of elastic fluidity.
The shining matter, he concludes, must exist in the manner of
empyreal luminous or phosphoric clouds. The planetary atmosphere of
the sun, its great height, its density, as inferred from the power of
gravitation, which is known to be twenty-seven times stronger at the
sun's surface than with us, and other subjects are also discussed. He
supposes the gas to pass from the sun itself upwards to the region of
the clouds, so as to generate pores, corrugations, &c. He concludes
finally, that if this view of the solar appearances be well founded,
there will be no difficulty in ascertaining the actual state of the
sun with regard to its energy in giving heat and light.

In a paper on the "_Construction of the Heavens_," the doctor thinks
it probable, that the great stratum called the milky way is that in
which the sun is placed, though perhaps not in the centre of its
thickness. The celebrated astronomer Lalande supposes the _spots_
before mentioned to be parts of the solid body of the sun, but admits
not a luminous atmosphere, but a luminous ocean. For the observations
of Dr. Young, see his _Natural Philosophy_, and of sir _Isaac
Newton_, his _Principia_, &c. Consult also Biot.

Sir Isaac Newton has asserted, according to Nicholson, (_British
Encyclopedia_) "that the density of the sun's heat, which is
proportioned to his light, is seven times as great in Mercury as
with us, and that water there would be all carried off in the shape
of steam, for, he found, by experiments with the thermometer, that a
heat seven times greater than that of the sun's beams in summer will
serve to make water boil." That fixed stars are of the same nature as
the sun, since they agree with it in several particulars, as in the
property of emitting light continually, and in retaining constantly
their relative situation with but little variation, is generally
admitted. They are supposed also to emit heat as well as light. The
sun is, therefore, considered a fixed star comparatively near us, and
the fixed stars, which seem as centres to other systems of worlds,
as suns at immense distances from us. Taking the distance of the
sun from us to be, as is found by calculation, 95,000,000 miles, we
may infer, that every thing must be scorched up at its surface; but
this question is put at rest, if we consider that the sun's rays
act on a calorific medium, as the cause of changing quiescent into
distributable heat. May not light itself, by some process unknown to
us, produce calorific rays? That heat and light are both material,
and possess some properties in common, that for instance, of
reflection and refraction, are facts well known; but to account for
the peculiar agency of light, if it be admitted, is a problem, which,
perhaps, will never be settled?

[4] _Fire_ must have been a very potent instrument in the hands
of Hannibal, if we believe what Livy and Pliny assert respecting
the means he employed in crossing the Alps, which took him fifteen
days, after meeting with almost every obstacle. Livy tells us, that
Hannibal softened the rock by pouring vinegar upon it, after it had
first been made hot under flaming piles of huge trees! M. Rollin
quotes Pliny to prove that vinegar has the _force_ to break stones
and rocks! This story is altogether fabulous; for in the first
place, had he vinegar sufficient; and, secondly, who ever knew that
vinegar had force, or even the power of dissolving primitive rocks,
such as granite or gneiss; and, thirdly, if it possessed the power
stated by Pliny, and had he a sufficient quantity, where was his
wood? For Polybius assures us, that Hannibal had no wood to make a
fire with, and that there was not a tree in the place, where he then
was, nor near it. That Hannibal passed over the Alps into Italy, and
at an inclement season of the year, is certain, and that it was one
of the greatest achievements that an enterprising commander ever
accomplished, is generally admitted.

[5] Respiration is a mechanical and chemical process, and consists
in alternate inhalation and exhalation, which, in consequence of
the oxygen gas in the air, effects a change in the venous blood
that enters the lungs from the pulmonary artery. Now as this blood
is charged with carbon, to which its dark purple colour is owing,
it is carried off in union with oxygen in the form of carbonic
acid. Hence carbonic acid is produced in respiration and the venous
blood is changed into the bright red arterial blood. A common sized
man will consume about 46 thousand cubic inches of oxygen _per
diem_; equivalent to 125 cubic feet of air, and makes about twenty
respirations in a minute, or for every seven pulsations breathes
twice.

[6] Of this fact the reader may form some idea, when he is informed,
that Newton's Principia, Biot's _Physique_, _Hatchette_, _Gregory_,
&c. &c. form the class books of instruction, works which require deep
study, and profound thought.

[7] Various applications of chemistry, among which that to gunpowder,
drew my attention at an early period of life. In the Aurora of
Philad. I published a series of essays on this and other subjects,
which, from the letters received at that time, I flatter myself
tended in some degree to advance the manufacturing interest in the
United States; an interest, which is connected with our individual
and national prosperity, and the _permanent_ and _practical_
independence of the republic. These essays were entitled "Application
of chemistry to the arts and manufactures," and published in 1808.
I have since enlarged that plan in the Artist's Manual, &c. 2 vols.
8vo. While noticing this subject we may add, that, having the honour
of being one of the few of the original society of Philadelphia
for the promotion of National Industry, whose essays excited, as
they claimed, the attention of the citizens of the United States,
much is due to the indefatigable labours of some of the members of
that association. We are greatly indebted to the able and masterly
pen of SAMUEL JACKSON M. D. Professor of Pharmacy in the college
of Apothecaries, of Philadelphia, for many of the best essays it
produced, whose disinterested motives, liberal and exalted mind, and
pure patriotic feeling prompted him to the laudable undertaking;
and whose essays were full, clear, and comprehensive. Viewing his
talents, his worth, his merit, we may truly add, that he is not
only an honour to the country which gave him birth, but an ornament
to the age in which he lives. The able address of the Philadelphia
Linnæan society, penned and signed by him, the late Samuel Benezet
M. D., and the author, as a committee, although written many years
ago, contains the principles, which are now advocated for the support
and encouragement of national industry. This address was calculated,
however, to promote, at the same time, the interests of Natural
History.

[8] Incombustible cloth made of this substance was formerly in use,
not only for domestic purposes, but, also to retain the ashes of the
dead from those of the funeral pile. Cloth made of amianthus, when
greased, or soiled, may be cleansed by throwing it into a bright
fire. It is then restored to a dazzling white colour. Pliny, the
naturalist, saw table cloths, towels, and napkins of amianthus taken
from the table of a great feast, thrown into the fire, and burnt
before the whole company; and by this operation, he says, they became
better cleansed than if they had been washed.

Pontoppidan (_Natural History of Norway_) remarks, that he has a
piece of paper made of the Norway asbestus, which, when thrown into
a fierce fire, is not in the least wasted, but what is written on it
totally disappears. In Norway, the stone flax is prepared by beating
it in water, till the fibres separate, which are repeatedly washed,
and then dried in a sieve. It is afterwards spun, observing to
moisten the fingers with oil.

[9] In the year 1601, a horse, which had been taught to perform a
number of tricks, was tried, as possessed by the devil, and condemned
to be burnt. Joblonski affirms in his _Lexicon, &c._ that he was
condemned to the flames in Lisbon. Nothing was a greater imposition
on mankind than the Oracles. The imposition of causing statues to
speak, as the head of Orpheus in the island of Lesbos, the Æsculapius
of Alexander, &c. may be readily perceived, when Lucius relates,
that, in the case of Alexander's oracle, he took instead of a pipe,
the gullet of a crane, and transmitted the voice through it to the
mouth of the statue! Bishop Theophilus, in the fourth century, broke
to pieces the statues at Alexandria. He found some which were hollow,
and placed in such a manner against a wall, that a priest could
slip unperceived behind them, and speak to the ignorant populace
through their mouths. Professor Beckman observes, "that the Pagan
priests, like our jugglers, were afraid that their deceptions, if
long practised, might be discovered. They considered it, therefore,
as more secure to deliver the answers themselves, or cause them to
be delivered by women instructed for that purpose, or by writings,
or by any other means. We read, nevertheless, that idols, and the
images of saints once spoke; for at present the latter will not
venture to open their mouths. If their votaries ever really heard
a voice proceed from the statue, it may have been produced in the
before-mentioned manner." We think, that a contrivance, similar to
the bull of Phalaris, in the place of hollow statues, would furnish a
good reality.

The oracle of Apollo at Delphos, says Percy, having been consulted
about the manner of stopping a plague then raging at Athens, returned
for answer, that the plague should cease, when Apollo's altar,
which was cubical, should be doubled. The philosophers of Athens
immediately applied themselves to discover the duplicature of the
cube, which henceforward was called the Delian Problem, and continued
for a long time to be an object of the keenest pursuit to the
curious. The first who discovered the solution was Hippocrates Chias.

[10] Signs in the heavens were believed by the ancients; and even
with regard to natural occurrences, they produced melancholy and
awful reflections. Augustus Cæsar was so afraid of thunder and
lightning, that, though he carried about him a skin of a sea-calf,
which was in those days accounted an excellent _paratonnerre_, yet,
whenever he saw a tempest coming, he used to fly for refuge to some
vaulted place underground. Caius Caligula rivalled Augustus in this
respect; for Suetonius observes, that when it thundered, he would
wrap his head in some covering; or, if in bed, leap out of bed and
hide himself under it.

[11] By means of a solar microscope, I have seen the animalcula in
vinegar several inches in length, some of which had the appearance of
eels, and in motion.

[12] There is a sort of mountebanks not only in Ceylon, but in
many other parts of the East Indies, who make a trade of taming
serpents, which they pretend to do by _incantation_, and carry them
about by way of show. I once witnessed the _taming_ of a serpent, a
black snake about four feet in length, by an English gentleman at
Harrowgate, in the neighbourhood of Philadelphia. He was remarkably
fond of snakes for _pets_, and had them not only to follow him, but
also to be about in the house among his children, who became familiar
with them; and, although young myself, I observed that they were
passive and obedient, and knew by instinct their _dependence_ on his
favours.

The _incantation_, that Mr. C--d used, was simply this: The snake
was put into a room, and Mr. C. took in with him a bowl of milk, and
the door was closed. Having taken off his coat, and put on a glove,
he proceeded towards his antagonist, who, being prepared for the
attack, made at him, but was repulsed; a second and third attempt was
made, but he was thrown back as before. The snake finding himself
_mastered_, did not think proper to renew the combat, and crawled
into the corner panting for breath. Mr. C. now took some of the milk
and placed it before him, without the least fear, and after he had
finished it, he gave him more. This he continued until the snake was
satisfied. After which, to the astonishment of all who witnessed the
experiment, he took it up, and having wound itself round his arm, he
carried it home. Whether he examined his mouth, destroyed the fang,
or the vesicular sac, (if it had one), I do not recollect; but this
same snake was afterwards a _great favorite_, and would follow his
master like a dog, and even play about with the children. I mention
this incident to show, that serpents possess considerable instinct,
and are, like domestic animals, conscious of their friends and
benefactors, and may be trained in the same manner.

In the island of Ceylon, there is a small animal called the
Indian Ichneumon, which destroys snakes in abundance; but, what
is remarkable, he only attacks them in an open place, where he
has an opportunity of running to a certain herb, which he knows
instinctively to be an antidote against the poison of the bite, if
he should happen to receive one. The monkeys of India, knowing the
malignity of snakes, make a business of hunting and destroying them
at night; after seizing them, they carry them to a stone, and beat
their heads until the fangs are destroyed, and then exultingly throw
them in the air. The poison is lodged in two small vesicles, and when
the animal bites they are squeezed, and the poison is forced through
the fangs into the wound. If the vesicles be extracted, or the liquid
prevented from flowing into the wound, the bite is harmless.

[13] The great cave on Crooked Creek, was discovered about the year
1800, by Mr. Baker. He proceeded only a small distance into it. On
the succeeding day, he brought his wife, and two or three children to
explore it. He carried a torch, which he accidentally dropped. During
two days and two nights, this family wandered in total darkness,
though sometimes within the hearing of a cataract, when, fortunately,
Mrs. Baker, in attempting to support herself on a rock, perceived
that it was wet. She conjectured that it was caused by the mud, which
they had brought in upon their feet. Baker immediately ascended the
rock, and saw the light of day.

[14] There can be no doubt, as we observed, that miasma is variously
compounded; but there is no certainty, as to what it is composed of,
or what modifications it may assume. That it is, however, a chemical
combination, and may be decomposed, and destroyed by chemical agents,
appears equally true. The disinfecting apparatus of Morveau, sundry
fumigations, &c. are used for this purpose. The proper destroyers of
these gaseous poisons, are nitric acid vapour, muriatic acid, and
chlorine. The two last are the most effectual. How would chlorine
gas act on prussine gas, or cyanogen? Would it not deprive it of its
carbon, forming the chlorocarbonic acid, and thus set the azote at
liberty, or might it not unite with the nitrogen, and form a chloride
of nitrogen? Suppose the cyanogen to be combined with hydrogen, the
decomposition of the hydrocyanic acid would be effected first by the
chlorine combining with the hydrogen, forming muriatic acid, and
secondly with the carbon, forming chlorocarbonic acid. If hydrogen,
in any other combination, should exist, would not the chlorine
in every case decompose such compound, and thereby destroy its
deletereous properties by taking away its hydrogen? I think it will
be proved, some time or other, that the miasma, which produces yellow
fever, is a compound of carbon and azote, with hydrogen, acting under
particular circumstances and conditions.

Various other means, besides those we have stated, have been
recommended to prevent the effect of contagious matter, such as
odoriferous substances, preparations of camphor, aromatic vinegar,
called the vinegar of four thieves, &c. but all come short of the
effect, and may be regarded as nostrums. The vapour of burning
sulphur, or sulphurous acid, is used in the East against the plague;
but this is inferior to either of the other acids, of which chlorine,
formerly called oxymuriatic acid, is to be preferred. A mixture of
four parts of common salt, one of black oxide of manganese, and two
of sulphuric acid, or muriatic acid poured on manganese or red lead,
will generate chlorine gas. Morveau's disinfecting apparatus contains
the above mixture. The free use of this gas in apartments, &c. &c.
cannot be too strongly recommended.

[15] On this subject, see a paper by Mr. Howard in the English
Philosophical Transactions, for 1802, and by Vauquelin in the
_Journal des Mines_, No. 76.

[16] For the history of saltpetre, the reader may consult, with
advantage, Beckman's _History of Inventions_.

[17] "The affinity of charcoal for oxygen is so considerable, that
instances have been known of its undergoing spontaneous combustion by
simple contact with the air. An occurrence of this kind took place
at the powder mills of Essonne, in France. (An. de Chim. 36, p, 93.)
A large quantity of recently burnt charcoal had been ground in the
usual manner, and was deposited in a large receptacle for future use;
some days after, the door of the magazine being opened, in order to
remove a part of the charcoal, an extraordinary heat was perceived,
and immediately a train of fire was observed, spreading over the
surface of the charcoal, and which was not extinguished without much
difficulty." Aikin's _Chemical Dictionary_, vol. i, p. 238.

[18] This apparatus will heat the air in a room to 84° in the coldest
weather, and is particularly calculated for cotton mills, and other
purposes. His invention is considered to be a judicious application
of a well known principle. Count Rumford heated rooms in a similar
manner by steam, which may be seen in the Repository of Arts vol.
xv, p. 186. A Mr. Green of Wandsworth, England, obtained a patent
in 1793, for warming rooms, by heated air, heated with steam. Steam
pipes, however, are now in use in the United States. In consequence
of the great quantity of latent caloric in steam (about 1000 degrees)
which is given out as free heat in its condensation, this principle
has been judiciously applied not only to the warming of apartments,
but to the boiling of dye kettles, and other purposes. See an account
of Woolf's steam apparatus, subsequent pages.

[19] The principal workmen they describe, are a master powderer, a
master carpenter, a master cooper, a head boy, (_Garçon_) employed
in the pulverization of the substances, another for the fabrication
of charcoal, one for every mill, besides workmen for aiding in the
charring, for the mill, &c.

[20] _Traité sur l'art de fabriquer la poudre à canon_, par MM.
Bottée et Riffault may be consulted.

[21] This is a mixed gas, composed of carburetted hydrogen, and
carbonic oxide.

[22] His son wrote a work, having the following title: "Thoughts
concerning that last and most perfect work of nature, and chief
of metals, gold, its wonderful properties, generation, affection,
effects, and fitness for the operations of art; illustrated by
experiments," from the Latin. Hamburgh, 1685, 8vo.

[23] In the year 1777, Lord Mahon, afterwards Earl Stanhope,
exhibited some experiments, to prove the certain, cheap, and simple
method of securing houses against fire, without making use of either
brick, stones, tiles, iron, or any such incombustible material. A
building, entirely constructed of wood, and of lath and plaster, with
a very small quantity of sand laid under the floors, which were of
deal, was attempted to be set on fire by means of a large quantity of
dry burning fuel, faggots, straw, pitch and other combustibles, with
which the lower room of this building was filled, from the floor to
the ceiling almost in every part. The whole mass of fire burnt out
without doing the least damage. Those who were in the next story,
directly over the conflagration, did not perceive the least degree of
heat. A wooden stair case, made in the same manner, also resisted the
flames.

[24] The imitation of thunder, rain, hail, &c. for theatrical
purposes, is variously performed. Mr. Nicholson, in describing an
exhibition he saw in London, (See Phantasmagoria,) remarks, that
thunder was imitated very accurately, by means of sheet iron plates.
The noise of rain and hail may be imitated by procuring a thin hollow
cylinder of wood, about ten inches wide, and two or three feet
long; dividing its inside into five equal parts, by boards, placed
obliquely, of five or six inches, observing to let there be between
them and the wooden circle, a space of about one-sixth of an inch,
and then introducing about four or five pounds of shot, and turning
it upside down. The shot will pass through the various partitions,
and resemble the fall of rain. If large shot be used, the noise will
be increased, and resemble hail.

According to the _Dictionnaire de l'Industrie_, (article _Tonnerre
artificiel_), thunder is imitated, by making a hexangular case of
sheet iron, and putting stones or small balls into it, and rolling
it more or less swiftly. Another mode is to roll cannon balls on a
floor, on which is loosely nailed, at certain distances apart, strips
of wood or lath. A clap of thunder is imitated by letting fall on
each other, very suddenly, a number of sheet iron plates, having them
previously suspended, or strung on a cord, which must be vertical. In
1784, M. Michael, (_Journal de Paris_) made a machine, which imitated
thunder, so completely, as either to produce the most violent
clap, or the most distant rumbling, with intermediate variations.
Parchment, stretched over a frame, has likewise, been used for the
same purpose. The distant thunder may be represented in this manner;
but, to produce a sharp noise, or clap, something more is required.

[25] Whoever walked the streets of Rome, at night, without a lantern,
was under the necessity of creeping home in perfect darkness, and
in great danger, like Alexis, in Athenæus. Antioch, Rome, and a
few other cities had public lanterns in streets which were most
frequented. Libanus, who lived in the beginning of the fourth
century, in praising his native city, Antioch, says, that "the light
of the sun is succeeded by other lights, which are far superior to
the lamps lighted by the Egyptians on the festival of Minerva of
Sais. The night differs from the day only in the appearance of the
light. With regard to labour and employment, every thing goes on
well. Some work continually; but others laugh and amuse themselves
with singing." In another passage, in the oration to Ellibichus,
the same author tells us, that the ropes from which the lamps that
ornamented the city were suspended, had been cut by some riotous
soldiers, not far from a bath. "Proceeding," says he "to a bath, not
far off, they cut, with their swords, the ropes, from which were
suspended the lamps that afforded light in the night-time, to show
that the ornaments of the city ought to give way to them." Jerome
also makes it appear, that Antioch was lighted with lamps; for, he
remarks, that, in an altercation between a Luciferan and an Orthodox,
an adherent to the schismatic Lucifer disputed in the street with
a true believer, till the streets were lighted, when the listening
crowd departed, and that they spat in each other's face, and retired.
Edessa, in Syria, was lighted in the fifth century, and the governor
of that city ordered, that a part of the oil, which was before given
to the churches and monasteries, should be burnt in the streets.
While illuminations were considered emblematical of public rejoicing,
the reverse was considered a token of public sorrow; to denote which,
on occasions of great misfortune, it was customary not to light the
streets. Valerius quotes a passage of Libanius in proof of this
assertion, where it is said, that the people of Antioch, in order to
mitigate the anger of the emperor, bethought themselves of lighting
either no lamps, or a very small number. In 1588, Paris was lighted
up with _falots_, or vases filled with pitch, rosin, and other
combustibles. The Abbé Laudati let out torches and lanterns in Paris,
in 1662.

[26] In the _Archives des Découvertes_, &c. several new lamps are
described, as follows: A lamp, invented by count Rumford noticed by
him in a memoir on the light of lamps, and the means of increasing
it; a new lamp with a double current of air, by Lenormand; star lamp
by Bordier; reverberatory lamp for towns, &c. by de Thirville and
Bordier; a modified thermo-lamp by Winsor; a new lamp by Baswell; the
economical lamp of inflammable gas, by Murdoc, and economical lamp
by Lambertin; the cupola lamp by Vivien; new lamp with a porcelain
reflector by L'Ange; the hydrodynamic and chemical lamp, by L'Ange;
the portable lamp by count Rumford; horizontal reflectors, with
parabolic surfaces in revolving, and parabolic reflectors, simple
and double, by Argand and Bordier Marcet; improved lamp, by Marcet;
thermo-lamp by Sobolewsky and Horrer; watch lamp by Dumouceau;
various lamps, with carburetted hydrogen; the polyflame lamp, of
Rumford; the curved lamp by Connain; the enamellers' lamp, and
hydropneumatic lamp by Tilley, &c. Davy's safety lamp is described
in Brande's _Chemistry_, and in Ure's _Chemical Dictionary_. See
_Aphlogistic lamp_.

[27] A solution of muriate of copper gives a green, of sulphate of
copper and muriate of soda, a light green; of sulphate of copper,
and ammonia in excess, a deep blue; a decoction of cochineal, or of
brazil wood, and a solution of tin, a deep red or scarlet, &c. These
solutions may be used for that purpose.

[28] Having mentioned in this article, the use of candles for
illumination, it may not be improper to observe, that they were also
employed for cooking, as will appear from the following incident.
In 1172, Henry II, of France, collected together the _feigners_ of
Languedoc, in order to mediate a peace between the count of Toulouse,
and the king of Arragon, at which Guillaume Gros de Martel gave a
sumptuous dinner, the viands being all cooked by the flame of _wax
tapers_!

[29] In the Archives des Découvertes et des Inventiones Nouvelles,
are several new inventions and improvements, relative to fire arms,
among which are the following: New fire arms, invented by Pauly,
which are said to carry a ball double the distance of ordinary
muskets, and to possess other advantages; for a particular account
of which, the reader is referred to the Bulletin de la Société
d'Encouragement, No. 99; another kind, by MM. Pauly and Prelat, which
primes itself, &c. and goes off by percussion; an improvement in guns
by using platina bushing, &c. by Lepage, with the use of priming,
composed of powder made of chlorate of potassa in lieu of saltpetre;
the improvement of Regnier in guns; improvement in the use of platina
for guns, to be used with the oxymuriated powder, by Debourbet; a gun
which fires fourteen times in succession without new loading, by M.
Henri; an improved carabine, which is discharged by percussion, by M.
Gosset, &c.

[30] Since 1792, musket-balls are seven-twelfths of an inch in
diameter, and twenty go to the pound instead of eighteen. In the
British service, eleven bullets to the pound are used for the proof
of muskets, and fourteen in the pound, or twenty-nine in two pounds,
for service; seventeen for the proof of carbines, and twenty for
service; and twenty-eight in the pound, for the proof of pistols, and
thirty four for service. The diameter of musket-bullets differs but
one-fiftieth part from that of the musket bore; for if the shot but
just rolls into the barrel, it is sufficient.

The diameter of any bullet is found, by dividing 1.6706 by the cube
root of the number, which shows how many of them make a pound, or it
may be done in a shorter way. From the logarithm .2228756 of 1.6706,
subtract continually the third part of the logarithm of the number
of bullets in the pound, and the difference will be the logarithm of
the diameter required. Thus the diameter of a bullet, whereof twelve
weigh a pound, is found by subtracting .3597270, a third part of the
logarithm of 12, from the given logarithm .2228756; or, when the
logarithm is less than the former, a unit must be added, so as to
have 1.2228756, and the difference .8631486 will be the logarithm of
the diameter sought, which is .7297 inches; observing that the number
found will always be a decimal, when the logarithm, which is to be
subtracted is greater than that of the pound; because the divisor is
greater than the dividend in this case.

Hence, from the specific gravity of lead, the diameter of any bullet
may be found from its given weight: for, since a cube foot weighs
11325 ounces, and 678 is to 355, as the cube 1728 of a foot, or 12
inches, is the content of the sphere; which therefore is, 5929.7 is
to 16 ounces, or a pound, as the cube 1728 is to the cube of the
diameter of a sphere which weighs a pound; which cube therefore is
4.66263, and its root 1.6706 inches, the diameter sought.

[31] A term used in the French Navy, to signify a wooden case or box,
in which cartridges are brought out of the powder-magazine for the
purpose of serving the guns; also a spoon or ladle, made of copper,
and fixed to a long pole, which serves to convey gunpowder into a
piece of ordnance.

[32] If sugar of lead cannot be had, and a substitute is required
which in fact is the same, we may dissolve white lead in vinegar,
until the latter is saturated. This may be used with water in the
same manner, using, however, more of it as it is in solution.

[33] Lee's adventure, just related, brings to mind another, by a man
of same name, not, however, with a submarine torpedo, or any thing of
that kind; but with a _sublunar_ aerostatic vessel, made about two or
three years ago, at Camden, opposite Philadelphia. This was a balloon
of an oblong shape, intended to float in the air like a ship on
water, and furnished with oars or wings. It was filled with hydrogen
gas. The object was to direct it, (a desideratum in aerostation),
like a vessel on water; but the aeronaut, having arose in his car
to the height of a lombardy poplar, which came in contact with it,
and judging a retreat was preferable, leaped on a limb, where he
had the misfortune to be caught by the seat of his pantaloons, and
appeared, as it were, suspended between heaven and earth, to the no
small diversion of thousands of spectators. The balloon ascended to
some height, and then turned, throwing out his sand bags, &c. which,
in the city, were taken for the unfortunate aeronaut, and produced,
of course, a contrary feeling. Lee called on me the next day, and,
in explanation of the cause, observed, that, when he ascended to the
height mentioned, he found the centre of gravity was shifting, and
thought it prudent not to venture. I observed, that it was well he
changed his gravity, but was sorry to find, that he had transferred
his centre a posteriori.

[34] A friend, who was a prisoner on board of Hardy's ship, very
facetiously observed, such was the dread of torpedoes by the British,
that they were literally afraid of _eating a potato, lest it should
contain a torpedo_!

[35] We are informed, that some rockets, which were made at the U. S.
Arsenal at Troy, were charged with the usual rocket composition, and
a small portion of quicklime, in consequence of which their power was
greatly augmented; a useful hint for their improvement.

[36] Star composition:--meal-powder 5 parts, saltpetre 16 parts,
sulphur 8 parts, antimony 2 parts.

[37] Four inches more likely.

[38] General Lallemand (Treatise on Artillery, vol. i, p. 26,)
observes, that the Congreve rocket is thirty inches in length, and
three and a half inches in diameter; that a part of its charge
consists of fire stone and small grenades; that their range is equal
to a long gun, but their direction is very uncertain; so much so
as to render them of little service, except to set fire to objects
with extensive surfaces; and that they will not pierce through solid
buildings, and in battle are at best only fit to frighten horses.

[39] In a note to Gibbon, page 283, we read, "The naphtha, the oleum
incendiarum of the history of Jerusalem (Gest. Dei per Francos, p.
1167,) the oriental fountain of James de Vitry (l. iii, c. 84,) is
introduced on slight evidence and strong probability." The name by
which Cinnamus call the Greek fire, corresponds with the locality
where naphtha was found, between the Tigris and the Caspian sea.
Pliny (Hist. Natur. ii, 109,) says, it was subservient to the revenge
of Medea, and according to the etymology, naphtha was signified.

[40] The _Fougasses_ and _Camouflets_, used in mining, are employed
for different purposes. The fougasses are small mines, whose line of
resistance is only six to six and two-thirds feet. They are used to
defend large posts. Bomb fougasses are nothing more than fougasses,
charged with bombs containing powder. To estimate the effects of
bomb fougasses, artillerists have ascertained the exact quantity of
powder contained in each kind of bomb. A bomb of eight and a half
inches weighs forty-six and a half pounds; it requires four and a
half pounds of powder to fill it; but one pound will burst it. The
eighteen inch bomb, or _cominage_, weighs nearly five hundred and
seventy-one pounds, and contains forty pounds of powder Thirteen
pounds of powder will burst it. The _camouflet_ is a small fougasse,
made to act against the enemy's mines, to suffocate and poison their
branch. The _camouflet_ is also used to act against the sides of
the crater of a mine that has been sprung. See _Science of War and
Fortification_, vol. 2d, p. 286.

[41] The _gramme_ is the French unit of weight, and is equal to the
weight of a cubic centimetre of pure water; it weighs 18.84 grains,
French. The kilogramme is equal to 1000 grammes. (2 lbs., 5 drachma,
49 grains, French.)

[42] Among other inventions, by this philosopher, such as the
detection of the adulteration of the crown of Hiero, mentioned by
Vitruvius, the cachleon or Archimedes' screw, the Helix for launching
large ships, the Trispaston for drawing immense weights, Pneumatic
and Hydrostatic engines, sphere, which exhibited the celestial
motions;--there are two in particular, which relate to the defence
of Syracuse, as well as the destruction of the enemy. Besides his
burning mirrors, Polybius, Livy, and Plutarch assert, that his
inventions for defence consisted of Tormenta, Balistæ, Catapults,
Sagittarii, Scorpions, Cranes, &c. Archimedes died in the 143d
Olympiad, 210 years before the birth of Christ.

[43] Certain plants, we have said, are made use of for this purpose.
Botanists have certain rules for distinguishing poisonous plants,
from those which are innocent. Professor Eaton (Manual of Botany,
&c. p. 17) observes, that plants with five stamens and one pistil,
with a dull coloured lurid corol, and of a nauseating sickly smell,
are always poisonous; as tobacco, thorn-apple, henbane, night-shade.
The degree of poisonous property diminished, when the flower is
brighter coloured, and the smell, less nauseous. He also observes,
that umbelliferous plants of the aquatic kind, and of a nauseating
scent, are always poisonous; as water-hemlock and cow-parsley. But
if they grow in dry land, and their smell is pleasant, they are not
poisonous; as fennel, dill, &c. Snap dragon, foxglove, and plants,
generally, with labiate corols, and seeds in capsules, are poisonous,
and also those plants which exude a milky juice when broken, unless
they bear compound flowers; as milk-weed and dog-bane. It is
understood, also, that plants having any appendage to the calyx or
corol, and eight or more stamens, are generally poisonous.

INDEX.

Accension of _glace inflammable_, 40

Accension of spirit of turpentine, 51

Accension of phosphuretted hydrogen gas, 85

Accension, spontaneous, remarks on, 288

Acid of borax, use of, in fire-works, 227

Aigrette, pots of, 363
why so named, _ibid_

Air works, 347

Alcohol, 168
the flame of, how coloured, 20, 269
its compound with water, &c. 169
its use in fire-works, 168
its proof, or strength, how ascertained, 170
used in the preparation of fulminating mercury, _ibid_
burns without smoke, _ibid_

Alexander the Great, surprised with the effects of naphtha, 32, 153

Albertus Magnus, published an account of the ordeal by fire, 38
on the Greek fire, 98

_Amadou_; see Pyrotechnical sponge.

Amber, 156
used in odoriferous fire, 157
found in the United States, _ibid_
black; see Jet.

Ambergris, _ibid_

American Turtle, what, 515

Ammonia, muriate of, 184

Analysis of gunpowder, in what it consists, 140

Ancients, fire-works of the, 261
as exhibited in theatres, _ibid_
made chiefly in wooden tubes, 262
illuminated on birth days, 428

Anelzin, Constantine, supposed to have invented gunpowder, 99

Animal poisons, for what used, 568

Animalcula, 34

Anglesea, Island of, furnishes sulphur from copper pyrites, 80

Antimony, 188

Antioch, had some public lamps, _note_. 428

Anna Commena, her formula for Greek fire, 98

Aphlogistic lamp, 170
with camphor, 171

Aquatic fire-works, 21, 442

Aquafortis, 49

Archbishop of Magdeburg had nitre districts, 52

Arrow, poisoned, 567

Archbishop of Triers, granted privileges for searching for nitre, 53

Artifice of destruction, 267

Artificial nitre beds, 69

Artificial flower pot, 10

Artillery, how fired by sulphuric acid, 75
match, 471
rod, 474

Arsenic, sulphurets of, 187

Arrows, used to attract lightning, 31

Asbestus, or Amianthus, wicks of, 26

Ashes, wood, 192

Asphaltum, 155
used as a cement, _ibid_

Aurum Musivum, 200

Auger rammer, what, 238
size of, for boring rockets, _ibid_

Auget in mining, what, 551

Automatons of fire, 419

Aurora, composition for, 272

Azote, iodide of, a fulminating compound, 177
in nitre beds, furnished by animal matter, 70
quantity of, in nitric acid, 122
disengaged from gunpowder, _ibid_
quantity of, disengaged from powder, 123
exists in miasmata, 60
carburet of, in miasmata, 61
different combinations of, _ib._

Bacon, Roger, 98
received his knowledge of gunpowder, _ib._
his work, containing the composition of powder, _ib._
his opinion of the manner the Midianites were defeated, _ib._
knew gunpowder before Schwartz, 99

Balls, incendiary, 92
smoke, 449
stink, _ibid_
poisoned, _ibid_
inflammable, 577
red-hot, 449

Balloon wheels, 394

Balloons of grenades, bombs and stone, 559
Coehorn, 351
Republican, 352
of serpents, 353
of crackers and marrons, 352
compound, _ibid_
eight-inch, &c. 353
ten-inch, &c. 354
observations on, 355
Table respecting, 356
Mortars for the charge of, _ibid_
fuses of, 354
composition for the, 358
cases for, 245

Barbadoes tar, 155

Barras, 148

Bar-Cochebra, the rabbi, his deceptions on the Jews, 31

Barrow's account of Asiatic fire-works, 255
the nitre caves of Africa, 58

Battle of the kegs, 523

Batteries of Roman candles, 406
Mosaic candles, _ibid_

Bavins, for fire-ships, 509
composition for, _ibid_

Beckman, his remarks concerning jugglers, 27

Bengal lights, 377

Benzoin, 161

Benzoic acid, _ibid_

Benzoin, why used in fire-works, 162
flowers of, _ibid_

Berard, his improvement in refining nitre, 67

Berthollet, proposed chlorate of potassa for gunpowder, 76
his fulminating silver, 174

Bergamot, the essence of, used in odoriferous flambeaux, 288

Bigot, his observations on rockets, 540

Bistre, how prepared from wood-soot, 146

Bitumen, elastic, 155
solid, _ibid_

Black, ivory, 90

Black lead, 209

Black amber, 157

Blue vitriol, 222

Blue stars, 18

Boat, plunging, 514

Bodington, invented a machine to prove powder, 139

Bologna phial, 214

Bones, charring of, 94

Bone and ivory, 220

Borello, his process for regeneration, 34

Bottle, phosphoric fire, 85

Bombs, howitzes and grenades, 487
tables respecting, 489
incendiary, of Ruggeri, 537
composition of, 556
where said to have been invented, 504
succouring, an account of Bell's, 544

Brass, 197

Brand, fire, 574

Brick, economical, 577

Brilliant stars, 18
fire, 271

Brins, pots de, 364

Brimstone, 78
roll, 80
how obtained, _ib._
how to determine its purity, 83
flowers of, 82

Browning of gun barrels, 204

Browne, Dr. on nitre caves, 54, 55, 58

Bronze, 198

Brongniart's directions for refining saltpetre, 62

Brugnatelli's fulminating silver, 174

Bullock's blood, paste made with, 253

Burgundy pitch, 147

Burning barrel, 503
composition for the, 504

Byzantium, illumination of, 24

_Cabinet de composition_, 235

Cadet, his mode of discharging guns, 477

Caduceus rocket, 341

Cagliostro, the imposter, 33
his pretensions to the miraculous, _ib._
his phial, _ib._
Cardan's account of his phial, _ib._

Cæsalpinus, his comment on Aristotle, 34

Callinicus, the inventor of the Greek fire, 544, 548

Calamine stone, 195

Calcareous caverns mostly contain nitre, 54

Caligula, caused Rome to be illuminated, 24, 428

Camphor, 157
used in candle-making, 159
obtained from the _Laurus Camphora_, 158
crude, how refined, _ibid_
properties of, 158
use of, in fire-works, 160
the flame produced by, _ibid_

Candles, Roman, 380
cases for, and effect of, _ibid_
manner of charging the, _ibid_
manner of firing, _ibid_
Mosaic, 381
duration of, 439
light of, _ibid_
Ure's experiments on, _ibid_

Cannon, history of, 456
how originally made, 457
different kinds of, 459
opinions respecting, 458

Carbon, gaseous oxide of, 89
different combinations of, _ib._
quantity in different coals, how ascertained, 151

Carbonic acid, 88

Carbonic oxide gas, 89

Carburetted hydrogen gas, _ib._

Cartwright's fire-works, 20

Caromel, 165

Carbonate of Ammonia, 185
zinc, impure, 195
potassa, 189

Castera's Plunging boat, some account of, 514

Caprices, 400
cracking, 407

Cascades of fire, 404

Carney, M. his process for gunpowder, 110

Carcass rocket, 530

Carcasses, 492
how made, 493
table of the dimensions of, 494
uses of, 492
composition of, 494
a general rule for their preparation, 495
composition for covering, 496
how discharged from mortars, 497
inextinguishable, 493

Cartridges, 462
musket, 464
cannon, 467
used in seiges, what kind of, 466
cost of, in France, _ibid_
ball for, calculations respecting, 463
dimensions of the sacks for, 468
cannon, of what composed, _ibid_
table relative to, 469
Bigot's table on the charge of powder for, 471

Cases, when drove solid, observations on, 237
how distinguished by their diameters, _ibid_
charging of, without moulds, _ibid_
nipples for, _ibid_
when charged solid, how bored, 238
rolled wet, for wheels and fixed pieces, 244
for turning pieces, of what length, 245
for Roman candles, _ibid_
for serpents, _ibid_
for fixed stars, _ibid_
tourbillon, _ibid_
balloon, how made, _ibid_
for illumination port-fires, 246
lances, 247
for common port-fires, _ibid_
paper for, 250
paper, preferred to wooden tubes, 262
used by the Chinese, _ibid_
for reports, 301
for crackers, 300
for fire-pumps, 322
for scrolls, 344
priming of, 370
whitening of, _ibid_
standing and fixed, compositions for, 388

Catamarin, 514
invented by Fulton, _ibid_

Caves, nitre, of the United States, 54

Celsius, his writings against the Magi, 27

Cement, Japanese, 252

Cerasin, 219

Chained rockets, 342

Chaptal, his approval of Carney's process, 110
his observations on saltpetre, 67

Christians in the first century, illuminated, 24, 428

Charcoal, 87
accension of, by nitric acid, 51
from damaged gunpowder, 72
quantity of, for decomposing 100 parts of nitre, 96
used in fire-works, 87
decomposes nitric acid, _ib._
nitrate of potassa, 96
properties of, 87
destroys the empyreumatic flavour of liquor, _ib._
burns in oxygen gas, &c. 88
one of the constituents of gunpowder, 89
how made, 90
how made intensely black, 96
for gunpowder, how prepared, 94
wood used for making, 94

Charred pitcoal, 90

Chargers, 231

Characters, used in pyrotechny, 230

Champy, M. his process for gunpowder, 109

Changes, in sun pieces, how effected, 396

Chemical effects in fire-works, 2
changes, _ib._

Chimnies, different modes of cleansing, 573
Smart's machine for, 574

Chinese fire, 19, 371
works, 255
preparation of the iron for, 201
composition of, as used in theatres, 265
for table works, 272
peculiar art of the, in making fire-works, 255
flyers, 303
cases for, _ibid_
how filled, _ibid_
use of, _ibid_
fountains, 405
paste, how made, 252
iron sand, different numbers of the, how made, 202
Incarville's account of the, 202

Chlorate of potassa, in fire-works, 7
accension by, 22
experiments with, _ib._
how made, 74
composition of, 75
decomposed by combustibles, 75
and sugar, give fire with sulphuric acid, _ib._
effects of, with charcoal and sulphur, 76
in lieu of nitre for gunpowder, _ib._
serious accidents from, _ib._
proportions of, for powder, _ib._
powder made with, stronger than the common, _ib._
powder of, experiments with the, _ib._
for rockets, 77
how used to discharge cannon, 75

Choaker, 233

Choaking, how performed, 243
contrivance for, 244

Cicero, lamps lighted in honor of, 24, 428

Clay, uses of, in pyrotechny, 193
how prepared for use, 194

Cleaveland, professor, his notices of saltpetre caves, 54

Coal, 149
common, _ibid_
pit, _ibid_
component parts of, _ibid_
character of, _ibid_
what kind of, best for fire-works, _ibid_
surcharged with bitumen, how it burns, 150
American, _ibid_
use of, in the arts, _ibid_
kinds of, _ibid_
quantity of carbon in, how ascertained, 151
why used in fire-works, _ibid_
analysis of, _ibid_
origin of, 152

Coke, 90
ovens, 150

Coehorn balloon, 351
illuminated, _ibid_
of serpents, _ibid_
of crackers, _ibid_
compound, 352

Colophony, 147

Colours, how communicated, 19

Combustion, spontaneous, how occasioned, 323
accelerated or retarded, 1
produces new compounds, 2
products of, _ib._
of metals, 4
of sulphur with nitre, 49

Common stars, 18

Compositions, remarks respecting particular, 9
how preserved, 235
sundry, for fire-works, tabular view of, 317
effects of particular, 367
for variations, for sun pieces, 396
to preserve the fuses of shells, &c. 485
for dipping curtains, bavins, &c. 511
for priming for fire-ships, _ibid_
for setting fire to fascines, _ibid_
for hoops, fire arrows, &c. _ibid_
for kitt, 512

Condensing syringe, 276

Courantines, or line rockets, 345

Constantius, alarmed at some feats by fire, 31

Constantinople, illumination of, 24
by order of Constantine, 428

Copal, 164

Cornelius, the Rev. Mr. his description of a nitre cave, 58

Corrosive sublimate, 186
use of, in fire-works, _ibid_

Cotton, 219

Counter-mines, 551

Crackers of fulminating silver, 173
how made for fire-works, 300
report of, how caused, _ibid_
Waterloo, 273

Crawfish, process for regenerating, 34

Cramer's experiments on the formation of nitre, 70

Cross-fire, what, 406

Crowns and globes, compositions for, 390

Cruikshank, his process for making fulminating silver, 174

Curtains, for fire-ships, 510

Cyanogen, 89

Cylinders, or rollers, 230

Cyphers in fire, how made, 324

Dana, his remarks respecting vapour in combustion, 434

Dart, the inflammable, 574

Dead fire, for wheels, 389
light fuse, 485

Deceptions by fire, various, 30

Decorations for fire-works, 298, 425

Deflagration of nitre with crude antimony, 50

Delian problem, (_note_), 28

Deliquescent salts in nitre, 38

Desaguliers, his remarks concerning rockets. See Rockets.

Destruction, artifice of, 267

Detonation with nitre and phosphorus, 49

Detonations, sundry with chlorate of potassa, 75
sundry experiments to produce, 273

Detonating mixtures with phosphorus, 85
girdle, 274
powder from indigo, 177
tape, 274
oil, 179
works, 273
balls, 274
cards, 275

Devices, variously formed, 324

Diamond, pure carbon, 87

Dodecaedron, representation of, 403

Don Pedro, 99

D'Orval, his account of aquatic fire-works, 272

Dragons, in fire-works, exhibitions of, 266

Driver for charging large rockets, 233

Drying of powder, 112

Duponts, the Messrs. the character of their powder, 73

Dusting of gunpowder, 112

Dung of camels, used as fuel, 218

_Eau de cuite_, 64

_Eau forte_, _ib._

_Eau faible_, _ib._

Europeans, ancient, their poisoned arrows, 568

Elastic bitumen, 155
aeriform fluids, 6

Electron, 156

Electricity, effects of, on inflammable bodies, 276

Ellibichus, (_note_.), 428

Empedocles knew the effect of burning glasses, 562

Endless screw, 418

Eprouvette, 138
of Hutton, _ibid_
improved, _ibid_
of Darcy, 76
of Regnier, 77
of Ramsden, 139
Dr. Hutton's opinion of the, 138

Eruption, volcanic, 263
substances which produce, _ibid_

Essence of spruce, 147

Ether, phosphorized, 85

Essential oils, 163

_Etoupille_ of the French, 295
how prepared, 297

Ewel, his patent for making gunpowder, 118

Examination, chemical, of nitre, 72

Exhibition of fire-works, 453

Experiments, sundry, with detonating substances, 273

Extemporaneous fire, 578
various kinds of, _ibid_
by chemical action, _ibid_
Hanzelet's composition for, 579
remarks on, _ibid_

Fascines, 501
how made, _ibid_
to what use applied, _ibid_
various kinds of, 501

Feast of the lanterns in China, 25

Feast of the lamps, 427

Feast of the dedication of the Temple, _ibid_

_Festum encæniorum_ of the Jews, 24

Fevers, malignant, supposed causes of, 60

Fight, with small ships, how represented, 451

Fire, feats performed with, 26
works of, general basis of, 19
works, to show in sparks, &c. 20
for rooms, of what made, 21
substances used in, 48
rain, incendiary, 560
composition of, 560, 561
observations on, _ibid_
gave rise to the fire-stone, 562
Greek, 544
of what composed, 545
flasks, 575
stone, what, 205
produced by percussion, 273
works in general, 255
invention of Europe, _ibid_
at Pekin, _ibid_
known in China from time immemorial, _ibid_
Chinese not surpassed by any nation, _ibid_
Barrow's account of the, _ibid_
arrangement of, 256
a system of, what, _ibid_
of inflammable air, 383
Frazier's opinion respecting, 257
ordeal by, 37
works at Versailles and Paris, 257
of the ancients, 261
theatrical, 262
rain for theatres, 264
composition of, 264, 309, 310, 311
in Chinese fire, 265
spur, 267
composition of, 268
works, portable, 271
scented, 283
tables, 271
pots, 365
for ramparts, 575
charge for, 366
brand, 574
pumps, 322
composition for, _ibid_
cases for, how made, _ibid_
how charged, _ibid_
jets, 367
extemporaneous, how made, 578
spouts, 367
compositions for, _ibid_
blue, for parasols and cascades, 369
radiant, _ibid_
green, _ibid_
Aurora, _ibid_
Italian rose, _ibid_
everlasting, what, 154
jets, different appearances of, 370
how used, _ibid_
Chinese, 371
red, 372
cast iron, used in the, 371
iron sand in the, _ibid_
applications of the, 375
has little force, _ibid_
on wheels, its effect, _ibid_
for calibers under 10/12ths of an inch, 376
for other calibers, _ibid_
for Palm trees and cascades, _ibid_
white, _ibid_
for gerbes, _ibid_
works for exhibition, the arrangement of, 387
how arranged, 453
incendiary, 490
general account of the, _ibid_
number of the, _ibid_
slow, for wheels, 389
dead, for wheels, _ibid_
wands, 400
cascades of, 404
galleries of, 406
globes, 420
crayons, 286
globe, aquatic, 445
representation of figures in, 423
ship, in miniature, 451
for service, 507
preparation of a, _ibid_
uses of a, _ibid_
stores required for a, 510
fire-barrels for a, _ibid_
composition for, _ibid_
stone, 491
its use, _ibid_
of what composed, _ibid_
cautions to be used in making, _ibid_
on what its goodness depends, _ibid_
how made more inflammable, _ibid_
composition of, 492
origin of, 491
composition, used for carcasses; see carcasses.
balls, 492

Fire balls, composition of, 494
table on the dimensions of, _ibid_
how they differ from carcasses, 492
composition for covering of, 496
how discharged, 497
a new mode for making, _ibid_
to be thrown by hand, kind for, _ibid_
composition for hand, 498
works, with hydrogen gas, 383
Dillon's exhibition of inflammable air, _ibid_
Cartwright's do. do., _ibid_
flame of hydrogen gas in, how charged, _ibid_
of inflammable air, how executed, _ibid_
their character, _ibid_
imitative, 440
how made, _ibid_
Red, for theatres, 270

Fixed air, 87
suns, 397, 398
cases, 19

Flame, the rapidity of the communication of, 431
of felt, colours of, 435
Reaumur and Schatt's remarks on, _ibid_
of felt, experiment to produce the, _ibid_
coloured, theory of, 436
very remarkable effects of, on living persons, _ibid_
how prepared to produce singular appearances, _ibid_

Flame, changed of different colours, 2, 432
deception by breathing, 30
the, in fire-works, how shown, 264
how extinguished, and made to reappear at the same time, 275

Flambeaux, odoriferous, 288
its use in war, 501
how made, 502
composition for, _ibid_

Flower pot, artificial, of fire, 10

Flowers of sulphur, 82

Flower pots, pyramid of, 402

Flux, black, 50
white, _ib._

Flyers, Chinese, 303

Fetid carbonate of lime, 155
fire, remarks on, 290

Forsyth, the Rev. Mr. his composition for gunpowder, 23, 75
his invention of a gun-lock, 22

_Foudres_, what, 265

Fougasses, 554

Fougette, 529
improvement on the, 530

Fountains, Chinese, 405

Frankincense, 148
used in odoriferous fire, _ibid_

Frazier, his opinion on fire-works, 257

Fruiloni wheel, 394

Fuel, economical, 577

Fulminating powder, 50
of Higgins, _ib._
mercury, 171
of Bayen, 173
silver, 173, 274
balls, _ibid_, _ibid_
bombs, 173, 275
silver, of Berthollet, 174
of Chenevix, _ibid_
of Silliman, 175
gold, _ibid_
platinum, 176
powder, from indigo, 177
compound, called iodide of azote, _ibid_
oil, 179
silver, entertaining experiments with, 273

Fusion, powder of, 50

Fuses, 481
for shells, howitzes, and grenades, _ibid_
how made, _ibid_
how charged, 482
sundry compositions for, 484
with dead light, 485
composition for the, 486
dimensions of, 487

Gallipot, 147

Galbanum, 221

Galleries of fire, 406

Galvanism, detonations produced by, 276

Games at Rome, illuminated at night, 24

_Garniture_, in fire-works, what, 298

Gases produced in fire-works, 6
character of the, _ib._

Gas lights, 89

Gases, what, produced by gunpowder, 121
number of, evolved from gunpowder, 122
carbonic acid, &c. quantity from gunpowder, 123

General theory of Pyrotechny, 1

Gerbes, 19
account of, 348
composition for, 349

Gibbs, colonel, his experiments on gunpowder with lime, 556

Girandoles, 407
modification of, _ibid_
chests of, for rockets, 338

Girdle, detonating, 274

Glazing of powder, what, 111
plumbago used for the, _ibid_

Glass, 210
different kinds of, _ibid_
acted upon by fluoric acid, 214
annealing of, _ibid_
uses of, in fire-works, 210

Globes, with their decorations, 419
leaping, 420
composition for, 421
bursting, 420

Globe of compression, 553

Glue, 214
its use in pyrotechny, _ibid_

Gold rain, 310
fulminating, 175

Gracchus, Marcus, 98

Græcus, Marcus, _ib._
said to have invented gunpowder, _ib._

Grape shot, how made, 470

Granulation of powder, 111

Grecian illumination, 24

Green match, 324
fire of the Palm tree, 77

Gregory, his summary of Robins's experiments, 125

Greek-fire, 544
invented by Callinicus, _ibid_
used by Callinicus with success, _ibid_
how defined, _ibid_
used at different periods, 545
how made use of, _ibid_
thrown by spouting engines, _ibid_
Beckman's remarks on the, _ibid_
peculiar properties of the, 546
modern imitations of the, _ibid_
La Brocquiere on the, _ibid_
Ruggeri's remarks on the, 547
said to have given rise to gunpowder, 98
recipes for the making of, known to Bacon, _ib._
a manuscript containing the, and gunpowder, _ib._
various kinds of, 546
the original, not known, _ibid_
the author of _Œuvre Militaire_ on, _ibid_
recommends a substitute for the, _ibid_
superseded by gunpowder, 547

Grenades, fuses for, 481
how charged, 484

Gums, used in fire-works, 21
contain carbon, 89

Gum arabic, 219
Tragacanth, _ibid_

Gun, repeating, 460

Guns discharged by percussion, 75

Guns, see cannon.

Gunpowder, history of, 97
invented in India, 97, 458
invention, how brought to Europe, 97
the Arabians obtained a knowledge of, from the Indians, _ib._
the use of, forbidden in the sacred books of the Indians, _ib._
employed in 690 at the battle of Mecca, _ib._
the Greek fire said to have given rise to, 98
recipe for, in an old manuscript, _ib._
quality of, 97
the formulæ for of Marcus Græcus, 98
said to have been invented by a German monk, 99
invention of, ascribed to Anelzin, _ib._
to Schwartz, _ib._
no mention made of, in the French registers, _ib._
damaged, nitre extracted from, 72
how examined by reagents, 73
analysis of, in what it consists, 73, 140
made with chlorate of potassa, 76
with chlorate of potassa, effects of, _ib._
what required to make good, 100
varies in its constituent parts, _ibid_
French formula, for the best, _ibid_
English, proportions used for, _ibid_
government, (British), what, _ibid_
experiments with, at Grenille, _ibid_
proportions for, by different nations, _ibid_
for war, French formula, 102
for hunting, do. do., _ibid_
for mining, do. do., _ibid_
manufacture of, 102
in France, summary of the, 110
improvement in the drying of, 103
glazing of, 104
for making, according to Champy, 109
mills, 104
accidents to, _ibid_
at Frankford, an experiment at, 105
machinery of, _ibid_
charcoal for, according to Proust, 110
Carney's process for making, _ibid_
its power, on what it depends, 120
gases produced by the combustion of, 121
quantity of, 122
Thenard's remarks on the gases from, 121
Proust's opinion of the products of fired, _ibid_
remarks on the combustion of, _ibid_
Granulation of, said to be injurious, 124
fired in a vacuum, the products of, 125
carbonic acid gas from, 121
Robins's experiments with, 125
Dr. Hutton's remarks on, 127
charges of, 129
the velocity of balls caused by, _ibid_
table of the charges, &c. of, 130
Hutton's experiments at Woolwich, with, _ibid_
azotic gas from, 121
proof of, 136
various, _ibid_
comparative, _ibid_
by the eprouvette, 138
strength of, how increased, 140
preservation of, _ibid_
examination of, _ibid_
chemical, _ibid_
marks, what, 136
quantity required to raise a cubic fathom of earth, 552
torpedo; see Torpedo.
several modes proposed to increase the force of, 554
experiments of M. L. Maitre, &c. with, 555
basis of fire-works. See Theory of Fire-Works.
extinguishing flame with fired, 572
charging of, with a ball, a new mode, 39
how used with ball, without injuring, _ib._
Tricks with, by jugglers, 40
action and reaction of, against a ball, _ib._
how put in the repeating-gun. See Cannon.
how it acts in extinguishing flame, 572
recommended to scatter water on buildings on fire, 573
inflammation of, by the radiation of heat, 566
cautions in loading guns with, 125
its force increased by confined air, _ibid_
how employed for the splitting of trees, &c. _ibid_
damaged, how the nitre is recovered from, 72
purification of sulphur, for making, 81
mills, spontaneous combustion in, 106
how prevented, 107
Bartholdi's opinion of the, 106
David's plan to prevent the, _ibid_

Gunbarrels, how browned, 204
utility of browning, _ibid_

Hanzelet, his extemporaneous fire, 579

Half-moulds, 238
dimensions of, _ibid_

Hare, professor, his remarks concerning flame, 433

Heat, latent, 136
idea of, how formed, _ibid_
in nitric acid, _ibid_

Herodotus, his account of the Egyptian illuminations, 24
of the Egyptian festivals, 427

Higgins, his fulminating powder, 50
improvement on the old, _ib._

Hirpi, the, jumped through fire, &c. 37

Hippocrates Chias, the discoverer of the Delian problem, (_note_.) 29

Holy Fire, office of the, 41
ceremonies of the, _ib._

Honorary rockets, 342

Horse, a, burnt, through a superstitious notion, (_note_.) 28

Humboldt, his observation on gunpowder for mining, 556

Howard's fulminating mercury, 172
of what composed, _ibid_
how prepared, _ibid_
effects of, 173

Howitzes, fuses for, 481
how charged, 484

Hughes' nitre cave, 54

Hydrogen gas, for fire-works, 20, 383
Cartwright's fire-works with, 20
Dillon's fire-works with, 383
detonation of, in a pistol, 384

Hyperboreans, how they caught the electric fluid, 31

Hyperoxymuriate of potassa, 7, 74
sundry properties of, 75
used for gunpowder, 76
the same as chlorate of potassa, 74
contains a large quantity of oxygen, 75
how prepared, 74
basis of the pocket lights, 75

Illumination port-fires, cases for, 246
lances of, 314
composition for the, _ibid_
of various colours, _ibid_

Illuminations, 23, 425
for what designed, 23
antiquity of, _ib._
Egyptian, 24
Parisian, _ib._
by the Ancients, on great occasions, _ib._
port-fire, composition for, 314
chemical, 439, 523

Illuminating barrel, 503

Illuminated table star, 273

Illuminated spiral wheel, 393
yew tree, 402
figures, sundry, 413
fountain, 439
how produced, _ibid_

Imitative fire-works, 440

Incendiary machines, in war, 462
fire-works, 490
matches, 492
kegs, 523
rocket, 530
rope, 558
composition for, _ibid_
arrows, 566

Incombustible, wheels, &c. how made, 240

Indigo, a fulminating powder from, 177

Indian white fire, 580
composition of the, _ibid_
matches for the, _ibid_

Ingenhouz, Dr. his remarks concerning gunpowder, 120

Inflammable powder of M. Gengembrie and Bottée, 50

Infernal machine, 512

Inflammable ball, 577
air, 20
works, 383
pistol, 384
lamp, _ibid_
dart, 574

Iodide of azote, a fulminating substance, 177

Iron cylinders and cases, why preferred for charring wood, 91
use of, in fire-works, 201
cast, or crude, an ingredient of Chinese fire, _ibid_
pig, or crude iron, 206
properties of, 201
the effect of, in brilliant and Chinese fire, _ibid_
sand of the Chinese, powdered cast iron, _ibid_
chambers of, for fire-ships, 509
their use, _ibid_
some preparations of, 201
theory of the effect of, in fire-works, 202
filings, how preserved, 239
in brilliant fire, 4

Irrorateur, 288

Isinglass, used in composition, 19
its properties, 214

Italian roses, 313
composition for, _ibid_

Japanese cement, 252

Jerome, his remarks on the lights of Antioch, (_note_.) 428

Jessamine fire, composition of, 271

Jet, 156
fire, 367

Jews, festival of, had illuminations at the, 24

Joblonski, his account of the horse condemned at Lisbon, (_note_.) 28

Julius Camillus, his homunculi, 34

Karabé, 156

Kircher, his mirror, 562

Kurtz, his patent for preparing charcoal, 93

Laboratory, in Pyrotechny, 228

Laboratory tools, _ibid_

Lampblack, in spur fire, 10
action of, in spur fire, _ib._
accension of, by nitric acid, 51
how made, 89, 144
origin of the name of, 144
houses, _ibid_
properties of, 145
purity of, how discovered, _ibid_
artificial tannin from, _ibid_
quality of, how improved, _ibid_
durable ink, prepared with, _ibid_
used in printers' ink, _ibid_
a constituent part of Close's ink, _ibid_

Lampadaria, what, 428

Lamptericæ, _ibid_

Lamp, inflammable air, 430

Lamps, kinds of, 429
various patent, (_note_.) 430
custom of the Turks with, 24
Pococke's account of, in a synagogue, _ib._
Persian ceremony with, 25

Lances of illumination, 314
sundry compositions for, _ibid_

_Lance à feu_, composition of, _ibid_
stink fire, _ibid_
slow white flame, 315
composition of, _ibid_
for petards, 318
how made, _ibid_
of service, _ibid_
composition for the, _ibid_

Lanterns, feast of the, in China, 25

Lapis Calaminaris, 195

Lardons, same nature as serpents, 298

Lead, recommended for the preservation of powder, 140
experiments with, for this purpose, _ibid_
cartridges formed of sheet, _ibid_
black, 209
used for the glazing of powder, 111

Leaders, 294, 295
threading and joining of, 294
for small cases, how used, _ibid_

Lee, Sergeant, his account of Bushnel's turtle, 518
his adventure with a submarine vessel, _ibid_
his adventure with a balloon-ship, (_note_.) 521

Libanus speaks of his native city, on account of the lamps,
(_note_.) 428

Lights, pocket, how made, 22, 75
various kinds of, 315
composition for, _ibid_
common, composition for, _ibid_
red, composition for, 316
sundry compositions of, for different calibers, _ibid_
brilliant, &c. composition for, _ibid_
for all calibers, _ibid_
another, _ibid_
large Jessamine, 317
small Jessamine, _ibid_
tabular view of compositions for, _ibid_
Bengal, 377
composition of the, 378
observations on the, _ibid_

Lightning, the Ancients knew how to attract the, 31
how represented, 267

Lime, promotes the formation of nitre, 53
the carbonate of, the same effect, _ib._

Lime, 194
its use in fire-works, 195

Line rockets, 345

Linseed oil, 218

Lixivium for slow match, how made, 293

Longchamp, his improvement in refining saltpetre, 67

Lycopodium used in priming powder, 76
imitating lightning, 267

Machines, infernal, 512

Magazine, 235
principles of forming a bomb proof, _ibid_
lightning rod for a, 236
access of moisture in a, how prevented, _ibid_

Magic lantern, 44
phantasmagoria with the, _ib._

Magi, character of the Ancient Egyptian, 27

Mallets, 231

Maltha, 155

Mandrils, 230

Marble, bituminous, 155

Marks, gunpowder, 143

Mariotte, his theory of the flight of rockets, 14

Marrons, 318
made to imitate the explosion of mines, 264
how made, 318
how fired, 319
batteries of, how formed, _ibid_
for service, _ibid_
cubical, _ibid_
figure of the paper, before forming, 320
shining, 320
for what designed, _ibid_
Murdering, 557

Mastich, 163
from the _Pistacia lentiscus_, _ibid_
used in the scented paste, 164

Matches, in artillery, 471

Match, 292
quick, _ibid_
slow, 293
lixivium for slow, _ibid_
principles with respect to the combustion of, 296
proportion of substances for forming, 297
slow (military), 471
how prepared, _ibid_
rope for, 472
lixivium for, _ibid_
nitre, why used, _ibid_
how polished, _ibid_
another process for preparing, _ibid_
how made at Gibraltar, _ibid_
made of sugar of lead, _ibid_
quick, process of M. Bigot for, 477
different compositions for, 478
of worsted, _ibid_
how made with expedition, _ibid_
rod, artillery, of M. Cadet, 474
experiments with, _ibid_
incendiary, 492
how prepared, _ibid_
phosphoric, 85
wood, 571
paper, 294
for cyphers, blue and green, 324
purple, or violet, 325

Meal-powder, 234

Mealing table, how made, 83

Mealing of brimstone, _ib._

Medici, house of, bribed to abolish the Academy del Cimento, 28

Mercury, fulminating, 171

Mercury, corrosive muriate of, 186

Metals, used in fire-works, 4

Metallic preparations, some detonate, 23

Metallic copper, how obtained by precipitation, 222
used in fire-works, 223

Meteors, imitation of natural, 325

Meteorolites, 62

Meteoric phenomenon, _ib._

Mexia, Peter, his remarks on gunpowder, 98

Miasmata, of what composed, 60
produce fevers, _ib._
produce yellow fever, 60
how destroyed, (_note_.) 61
kind of, supposed to produce yellow fever, _ib._

Military Pyrotechny, what, 456

Milk of sulphur, 83

Mine pots, 299
composition of, _ibid_

Mines, and mining, 550

Minerva of Sais, festival of, (_note_.) 428

Mineral tar, 154

Miracles, 29

Mirrors, powerful effects of, 562
Archimedes employed, with success, 563

Mix, lieut. his unsuccessful attempt with a torpedo, 522

Mixtures, how made for fire-works, 253

Morey, his experiment with nitre and oil, 51
with tar, 433
with rosin and boiling water, 432

Mortars and pestles, 233
paper, 350
to throw aigrettes, 350, 363

Moore, his remarks on rockets, 15

Moon and stars, 421

Mosaic candles, 381
theory and effect of, 17
gold, 200
tourbillons, 358
composition of, 360
simples, 381
how used, _ibid_
moulded stars, 382
composition of, _ibid_

Moses, how he differed from the Magi, 30
rod of, miracles wrought with the, 29

Mother water of nitre, 57

Moulds, for common port-fires, 247

Muriated gunpowder, what, 76

Muriate of Ammonia, 184

Mushet, his remarks on iron, 210

Mutations, a regulated piece of nine, 408

Myrrh, 164
used in odoriferous fire, 165

Naphtha, 153
the substance, which burnt Creusa, _ibid_
Alexander the great, surprised at the effects of, _ibid_
used by the Ancients in exhibitions, 154
Hanway's account of, _ibid_
Pinkerton's observations on, _ibid_
grounds, singular properties of, _ibid_
used in the Greek fire, 154

Neptune, how represented in fire, 450

Nitre, 48
fixed by charcoal, 49
used in the formation of gunpowder, 50
its quality, how judged of, by fire-workers, 51
how procured in the East, 52
districts, what, _ib._
how procured at Lima, _ib._
regale, in Germany, what, _ib._
how obtained in Germany, _ib._
from old walls, buildings, &c. 53
formed with animal and vegetable matter, _ib._
collected in the East Indies, _ib._
quantity used in China for fire-works, _ib._
bed of, at Apulia, near Naples, _ib._
how obtained in Switzerland, _ib._
springs, in Hungary, _ib._
convocation at Paris, of young men, to receive instruction for
forming, _ib._
Caves of the United States, 54
obtained from the soil of tobacco-houses, _ib._
beds, artificial, _ib._
how extracted from the nitrous earth of nitre caves, 54, 55
crude, what, 54
earth, what, _ib._
found in caves in a state of purity, _ib._
caves of Tennessee, Virginia, and Maryland, _ib._
cave, a, how discovered, 55
in the grease, what, 56
theory of the process of extracting, 57
crystallization of, _ib._
rough, _ib._
rock ore of, how treated, _ib._
caves, observations on, 59
Brongniart's direction for refining, 62
process for extracting, in France, 63
old process for refining, 66
Chaptal's observations, &c. on, 67
conditions necessary to form, 70
how extracted from damaged gunpowder, 72
how to ascertain its purity, _ib._
how reduced expeditiously to powder, 73
cubic, 74
caves of Africa, a bituminous substance found there, 58
native, in the nitre caves of the United States, 56
native, of Africa, 58
in the sandstone strata of Africa, _ib._
caves of Africa, contain animal excrement, _ib._
in the cave at Nicajack in Georgia, _ib._
quantity obtained at Nicajack, 59
supposed origin of, at Nicajack, _ib._
in the cave at Corydon, Indiana, _ib._
caves of East Tennessee, Kain's remarks on, _ib._
of the Cumberland mountains, _ib._
causes which are supposed to form, _ib._
used in the manufacture of candles, 186

Nitrification, what, 70

Nitrous efflorescence, the ancient _scrophula contra lapides_, 53

Nitrate of potassa, nitre, or saltpetre, 48
of soda, used in fire-works, 8
of strontia, _ib._
produces flame, _ib._
of soda, 73
experiments with, by Bottée & Riffault, 74
of copper, 223
uses of, in fire-works, _ibid_
use of, for matches, _ibid_
preparation of, _ibid_

Nitrates of different bases, may be used in fire-works, 8
all contain oxygen, _ib._

Nitric acid, 51
how prepared, _ib._

Odoriferous fire-works, general principle of, 21
water balloons, 286, 446
flambeaux, 289
and fetid fire, 290
fire, by spontaneous accension, 288
pastilles, or crayons, 286
vases of the ancients, _ibid_

Odour, classification of, _ibid_
extreme divisibility of, 285

Oils, essential, 163
inflammation of, 51
used in odoriferous fire, 285

Oil of vitriol, 82

Oil, phosphorized, 85
detonating, 179
linseed, 218
why required in boring of rockets, 238
used for the preservation of iron or steel filings, 239
of spike, 156
how prepared, _ibid_

Olefiant gas. See fire-works with hydrogen gas, 89

Ores, many, furnish sulphur by sublimation, 80
how treated to yield sulphur, _ib._

Orenburg gum, 147

Ordeal by fire, what, 37

Orpiment, 187

Oxygen gas, how obtained from nitre, 49
in nitrates and chlorates, 8
an important agent in fire-works, 2

Oxides, formed by combustion, what kind of, 4

Oxide of copper, in fire-works, 222
how obtained, _ibid_

Pagan Priests, conscious of their deceptions, 30

Palm trees, representation of, 401

Paper press, 234
different kinds of, used for cases, 250
how made incombustible, _ibid_
how coloured and glazed, 251
preferred for cases to wood, 262
cases used by the Chinese, _ibid_
touch, or match, 294
mortars, 349
Swedish stone, 250
incombustible, of amianthus, 251
Chinese, _ibid_
observations on, _ibid_

Parasols, Chinese, 405

Paris, fire-works at, in 1739, 257

Paste, 252
patent, _ibid_
Japanese, _ibid_
odoriferous, 287
board, how made, 249
uses of, _ibid_
for fire-works, Chinese mode of making the, 252

Pastilles, or pastes, 286
composition of, 287

Peach-wood, raspings of, 76

Pearl ash, 190

Perchloride of Mercury, 186

Persia, the sacred fire in, 386
grounds of, contain inflammable air, _ibid_
the followers of Zoroaster in, _ibid_

Petard, 298
for war, 505
table of the dimensions of the, _ibid_

Petards, composition for, 506

Petroleum, 154

Payard, M. his burning mirror, 565

Peyre, his remarks confined to gunpowder, 16

Phantasmascope, 47

Phantasmagoria, 44
thunder and lightning with the, 47

Phalaris, bull of; (_note_.) 28

Philosophical phial, 214

Phlogiston, supposed to have existed in acids, 70

Phosphorus, 84
general properties of, 85
how prepared, 86

Phosphoric matches, and fire bottles, 85
stone, 86
tapers, 85
pencil, 86
ether, 85
oil, _ib._

Phosphuret of lime, its effect in water, _ib._
of Wurzer, 86

Phosphuretted hydrogen gas, 85

Piece, regulated, of nine mutations, 408

Pinks, fire, from flower pots, 10

Pin wheels, 395
composition for, _ibid_

Pipes of communication, 443
for fire-works, 295
how joined together, _ibid_
how made, _ibid_
why necessary, _ibid_

Pitch, Jews', 155
how made, 147
use of, in fire-works, _ibid_
a composition of, almost inextinguishable, _ibid_
used in the Greek fire, _ibid_
used in incendiary fire-works, see military fire-works.
Burgundy, furnished by the Pinus Abies, _ibid_
white, _ibid_

Plane board, 233

Platinum, fulminating, 176

Pliny, his account of Porsena, 31
of Numa Pompilius, _ib._
of Tullius Hostilius, _ib._

Plumbago, 209

Plutarch, his account of Naphtha, 32

Pocket lights, how made, 22, 75

Poisoned arrows, 566
of savages, of what composed, 567
sundry plants for, specified, 568
the Arabs, how they make, _ibid_
of the island of Java, _ibid_
Asiatic, with what poisoned, _ibid_
of the Alps, _ibid_
ancient Europeans, how they made, _ibid_

Polydore Virgil, to whom he ascribes the invention of powder, 99

Polygonal mirror, its effect, 565

Pontiffs, the, considered learning opposed to their views, 28
their arbitrary edicts, _ib._
bribed the house of Medici, _ib._
abolished the academy Del Cimento, _ib._

Port-fire, cases for, 247
length of, _ibid_
origin of the term, _ibid_
how made, by the Strasburg formula, _ibid_
Strasburg, composition of, 248
how generally made, 479
instructions of M. Bigot respecting, _ibid_
composition of, various, _ibid_
usual length of, 480
wet and dry, _ibid_
dry, according to the English method, _ibid_
other compositions for, _ibid_
composition for, according to Ruggeri, _ibid_

Potash, 191

Potassium, _ibid_

Pots des Brins, 364
serpents for, 299
how made, 364
de chasse, 360
fire, remarks on, 365
for ramparts, 575
composition for, 366
of ordnance, 422
how made, _ibid_
how fixed, _ibid_
how discharged, 423
flower, pyramid of, 402

Powder-triers, 138
proof, 136
bags, 503
how made, _ibid_
barrel, _ibid_
of fusion, what, 50
fulminating, _ib._
inflammable, of Pauly, 577
of what composed, 578

Priests of antiquity, acting as jugglers, 32

Prince Rupert's drops, 214

Priming powder, of chlorate of potassa, 75
tubes, or fuses, 475
formerly made of tin, _ibid_
composed of two parts, _ibid_
reeds, or quills used for, _ibid_
how filled, 476
compositions, sundry for, _ibid_
pewter used for, 475

Prognosticator, a preparation of camphor for a, 159

Proust, his remarks on the charcoal for powder, 110

Prussic acid, 89

Puddling, what, 207

Puffs, 262
composition for, 263

Pulverization of substances, 253

Purple match, 325

Putrefaction of animal and vegetable substances, 70
forms saltpetre, 71

Pyrotechny, 1
general theory of, _ib._
of the Chinese, 53

Pyrotechnical sponge, 570
mixtures, 1

Pyroacetic acid, 91
how purified for use, 93, 95

Pyric piece, 412

Pyrophorus, 180
of Wurzer, 86
how prepared, _ib._

Pyrophore of defence, 581

Quick match, 20
how generally made, _ib._
military, 477
different kinds of, see match.

Quicklime, 194
its use in making slow match, 472

Radiation of heat, its effects, 565

Rammers, 231

Rampart fire-pots, 575

Realgar, 187

Reagents, chemical, to discover foreign salts in nitre, 72

Recoil of a gun, similar to the recoil of a rocket, 11

Reeds, for fire-ships, 510

Red-fire for theatres, 270

Resins, 148
Thenard's opinion of, _ibid_

Repeating gun, 460

Reports, single, 301
cases for, _ibid_

Rain, silver, composition for, 272
fire, 18
filamentous, 309
how formed, _ibid_
cases for, with what charged, _ibid_
in sparks, what, _ibid_
composition for, 310
gold, composition for, _ibid_
remarks on the, 319
fire, in general, sundry compositions for, 311
falls, and stars, double and single, _ibid_
observations on the cases for, _ibid_
and hail, how imitated, (_note_.) 266

Rays, composition for, 272

Rice glue, 252

Richardson, his tricks with fire, 36

Ring, a, how suspended by a thread reduced to ashes, 41

Robins, his conclusions applicable to rockets, 16
his experiments on gunpowder, 125

Rochos, on the ashes of toads, 34

Rock saltpetre ore, what, 55

Rockets, gunpowder, &c. causes the ascension of, 11
motion of, how balanced, 12
gases produced by the combustion of the composition for the, _ib._
principle of the, gives motion to fire-wheels, 11
a missile weapon, _ib._
used at the seige of Seringapatam, _ib._
principle, what, 12
employed for explosion and conflagration, 11
theory of the ascension of the, 12
stick, its use, _ib._
stars, 18
water, _ib._
charcoal of hard wood for, when used, 94
remarks on charging of the, 231
charging of the, rammers required for, _ibid_
signal, tools required for forming the, 232
table, 272
driving of a, 236
driven solid, or hollow, 236
ladle for charging, 237
blows required for charging of the, _ibid_
for each ladleful of composition, _ibid_
how bored, and machine for boring, 238
taps for, what, _ibid_
bored with a brace and screw bit, 239
cases, how made, 243
cases, Morel's rule for making, 244
length of the, how regulated, 245
and their appendages, 326
flying, _ibid_
uses of, _ibid_
caliber and preparation of, _ibid_
tables, concerning the, 327, 328
different opinions respecting, 327
moulds for, remarks on the, 328
composition for, remarks on the, _ibid_
charcoal used in the composition for, of what kind, 329
compositions for, opinions respecting the, _ibid_
compositions for, _ibid_
according to Morel, 330
to Bigot, _ibid_
tabular view of the, 331
of honour, Chinese composition for, 330
observations on charging of, 331
furniture of, its weight, 332
heads for, how made, _ibid_
sticks for, _ibid_
how measured, _ibid_
piercer, what, 333
rammers, for charging of, _ibid_
formers for the cases of, _ibid_
moulds for, table exhibiting the dimensions of, _ibid_
on the heading of, 334
heads of, why used, _ibid_
experiments respecting, 335
manner of decorating them, _ibid_
decorations used for, _ibid_
sticks, their dimensions and poise, 336
their use, _ibid_
table respecting, _ibid_
how discharged, 337
different modes of discharging, _ibid_
fired without sticks, in what manner, 338
Girandole chest for discharging, _ibid_
how made, 339
fountain of, what, _ibid_
how discharged at the same time, _ibid_
Morel's contrivance for discharging, _ibid_
angle of inclination given to, if required, 340
combinations of, with appendages, _ibid_
fixed on the top of each other, _ibid_
towering, 16, 340
Caduceus, 16, 341
Honorary, 342
Chained, _ibid_
tails of, how made to form an arch, 343
small, or swarmers, _ibid_
composition for, _ibid_
scrolls for, 344
cases for, _ibid_
line, with decorations, 345
signal, 347
water, 443
discharging of, in water, 448
under water, 449
war, 11, 526
Congreve, has iron cases _ibid_
Signal, _trimming_ of, _ibid_
composition for the trimming of, 527
quicklime used in the composition of, (_note_.) 526
the hollow in, increases the surface that takes fire, 527
sticks of, when large, are bored and filled with powder, 528
Robins's experiments with, _ibid_
height of ascension of, _ibid_
Indian, 529
Congreve, how it differs from the common, 530
contains the propelling power, _ibid_
carries ball, shells, case shot, &c. _ibid_
distance of its flight, _ibid_
carcass, _ibid_
how armed, 533
used at Boulogne and Copenhagen, 531
advantages it is said to possess, _ibid_
range of the largest kind of, 532
kinds used for different services, 533
table concerning the range, &c. of the, _ibid_
how discharged, 535
estimate of the cost of the, 536
French account of the, _ibid_
described by Ruggeri, _ibid_
Congreve said not to be the inventor of the, _ibid_
invented by a naval officer, _ibid_
Ruggeri's publication concerning the, _ib._
analysis of the, by Gay-Lussac, 531
objections to the, 537
difference between the incendiary and common, 538
murdering, how formed, _ibid_
how discharged, _ibid_
light ball, 539
carcass, the floating, _ibid_
observations on the, 540
Bigot's remarks concerning the, _ibid_
Bigot's tables of the different kinds of, 542, 543
the succoring, 544

Rolling board, 233

Rolled stars, 304

Rome, the forum at, lighted, 428
without public lights, _ibid_

Roman candles, 380

Roses, Italian, 313
composition for, _ibid_

Rose-piece and sun, 399

Rosin, 146
how prepared, 147

Ruggeri, his opinion of chlorate of potassa for rockets, 77

Rumford, count, his improvement in fuel, 577

Sacks, for mealing gunpowder, 234
of powder, for pots des brins, 366

Sage, on the spontaneous combustion of charcoal, 107
his remarks concerning gunpowder, 108

Sal Alembroth, 187
ammoniac, use of, in fire-works, 184
in candle making, 191
ammoniac, 184

Sal Prunelle, 49, 167

Saltpetre, the basis of fire-works. See Nitre, 3
affords oxygen, _ib._
decomposed by charcoal, _ib._
remarks concerning, 49
converted into sal prunelle, 167
refining of, 65
old process for refining of, 66
reagents used to determine the purity of, 72
Dupont's refined, character of, 73
how obtained in fine powder, _ib._
preparation of, for fire-works, _ib._
the oldest certain account of, 98
Caves. See Nitre.
proportion of acid in, 122
used in candle-making, 186

Saracen fire, 549

Saucissons, 321
how made, _ibid_
flying, _ibid_
how used, 322
in mining, what, 551

Scudder, his plan for blowing up the Ramilies, 524

Scrolls for rockets, 344

Scented vase, 288

Scented fire-works, 21, 283
vase of the Athenians, 21
fire of the Moldiva Islands, 285

Schwartz, said to be the inventor of gunpowder, 99

Schistus, bituminous, 155

Schœpfer revived magic, 33
and Cagliostro, tricks of, _ib._

Sea lights, 525
composition for, _ibid_

Sea fights, how represented, 451

Sieves, 234

Seneca oil, 155

Serpents, nest of, 364
how formed, 298
how driven, _ibid_
composition of, 299
for pots de brins, _ibid_
for pots of aigrettes, &c. _ibid_
why so called, _ibid_
stars, 301
their intention, _ibid_
cases for, _ibid_
compositions for, _ibid_
of two kinds, _ibid_
how moulded, 302
how primed, _ibid_
theory of their effect, _ibid_
whirling, _ibid_
principle of the, _ibid_
how charged, _ibid_

Ship, fire, 507
preparation of a, 507

Shells, paper, how made, 245
fuses for, 481
loading of, 484

Shining marrons, 320

Shrapnel shell, 559

Siemienowicz, Casimir, his fire-rain, 560

Signal rockets, 347

Silliman, professor, his fulminating silver, 175

Silver rain, composition of, 272
what, 18
fulminating, 173

Size, 215

Skin, the, how made callous, 36

Sky-rocket, see Rocket.

Smoke ball, composition of the, 507

Snakes, how tamed, (_note_.) 35
destroyed in India, (_note_.) _ib._
fangs of, what, (_note_.) _ib._

Solar phosphori, 437
the miraculous luminaries, no other than, different kinds of, _ibid_
phosphorus, Bolognian, _ibid_
Canton's, _ibid_
Hanzelet's, _ibid_
Baldwin's, _ibid_

Soot, why used in some pyrotechnical mixtures, 145
of what composed, 146
of animal excrement furnishes sal ammoniac, _ibid_
of camels' dung, its use in Egypt, _ibid_
of oil, and turpentine. See Lampblack.

Sparks, in rain-fire, 309
substances, which show in, 312

Spelter, 196

Spherical case shot, 559

Spiral screw, 418

Spontaneous combustion, 51

Spouts, fire, 367

Spirit of sal ammoniac, 185

Spirits of turpentine, 147

Spirit of wine, 168

Spirit lamps, 170

Spur fire, 9, 267
composition of, 268

Spunk, 570

Standing or fixed cases, compositions for, 389

Stands, for sky-rockets, 338

Stahl, his opinion of the composition of nitric acid, 70

Stars, from artificial flower pots, 10
simple, 303
use of, _ibid_
how prepared, _ibid_
composition for, 304
rolled, 304
how made, _ibid_
composition used for, _ibid_
cracking, _ibid_
are small marrons, _ibid_
rocket, white, composition of, _ibid_
blue, composition of, 305
variegated, composition of, _ibid_
brilliant, composition of, _ibid_
common, composition of, _ibid_
tailed, composition of, _ibid_
drove, composition of, _ibid_
fixed pointed, composition of, _ibid_
of a fine colour, composition for, _ibid_
of different colours, composition of, _ibid_
directions for preparing, 306
another composition for, _ibid_
which carry tails of sparks, _ibid_
composition of, _ibid_
which yield some sparks, 307
yellow, composition for, _ibid_
another composition for, _ibid_
caution in rolling, _ibid_
different ways of forming, 308
flaming, with brilliant wheels, _ibid_
general theory of, _ibid_
fixed, 313
scrolls for, 344
strung, _ibid_
moulded Mosaic, 382
flat, 424

Steam, how used for drying gunpowder, 112, 116, 119
pipes, what, 112
latent heat in, (_note_.) _ibid_
for boiling dye kettles, (_note_.) _ibid_
Count Rumford's experiment with, (_note_.) _ibid_

Steel, its use in fire-works, 201
combustion of, in oxygen gas, 202
hardening of, 204
tempering of, _ibid_
natural, 207
kind called ferrum candidum, 208
of cementation, 207
singular mode of making, in Spain, 208
blistered, 207
antiquity of hardening, 208
shear, 207
cast, _ibid_
or iron filings, how preserved for fire-works, 239
filings, in spur-fire, 10
produce scintillations, _ib._
of what composed, 89

Stink fire lance, 507

Stink stone, 155

Strangling of cases, how performed, 243
contrivance for, 244

Strangler, 233

Streets, lighting of the, a modern invention, 26

Storax, 162

Substances, what, required for military fire-works, 228
pulverization of, 253
properties of various, known to jugglers, 26

Submarine navigation, 515

Succinum, 156

Succinic acid, 157
its effect in fire-works, 290

Suffocating pot, 507
composition for the, _ibid_

Sugar, 165
used in fire-works, _ibid_
decomposed by chlorate of potassa, _ibid_
from various substances, 166
caromel from, by the burning of, 165
sulphuric acid converts several substances into, 166

Sulphur, 78
native, _ib._
in the island of Java, _ib._
associated with gypsum, _ib._
volcanic, 79
how obtained from ores, 78
how purified for gunpowder, 80
mineralizes metals, _ib._
from pyrites, _ib._
vivum, what, _ib._
how recovered, from damaged gunpowder, 72
from galena, 79
various means of obtaining, 80
quantity obtained, from pyrites, 80
quantity of in metallic sulphurets, 79
roll, 80
flowers of, _ib._
properties of, 82
various compounds of, _ib._
a constituent part of gunpowder, 83
mealing of, _ib._
how to determine the purity of, _ib._
to discover the adulteration of, by oil of turpentine, 84
milk of, 83
use of, in preserving iron and steel, 239

Sulphuret of arsenic, 187
antimony, 188

Sulphurets, 82

Sulphuric acid, _ib._
native, in the island of Java, 78

Sulphurous acid, 82

Sun cases, 19

Suns, &c. exhibition of, by the Chinese, 256

Suns, fixed, 397
with transparent faces, 398
with variations, 396
compositions for the charges, _ibid_
with rose piece, 399

Swarmers, 343
composition for, _ibid_

Swedish melting house, feats performed at the, 36

Sword blades, how ornamented, 205

Table, mealing, 234
fire, 271
works exhibited on, _ibid_

Table rocket, 272

Table-star, the illuminated, 273

Tape, detonating, 274

Tar, how obtained, 147
Barbadoes, 155
Morey's experiments with, 148

Tarred links, 500
how made, _ibid_

Tests, their use in discovering the presence of substances, 72

Thenard's formula for priming powder, 76

Thenard, respecting nitrous lixivium, 63

Theophilus, bishop, respecting the statues at Alexandria, (_note_.) 28

Thick stuff, of nitre boilers, 57

Thouvenal's opinion respecting nitre beds, 70

Thundering barrel, 504

Thunder bolts, in fire-works, 265
composition for, 266
various ways of imitating, (_note_.) _ibid_
accompanying the phantasmagoria, how imitated, (_note_.) _ib._

Thus, 148
used in odoriferous fire, _ibid_
copallinum, 164

Tin, sheet, 206
plate, _ibid_

Tinder, 570

Tools and utensils, 228

Tophania, the female poisoner, 48

Torpedo, Fulton's, 521
principle of, _ibid_
precautions against, 522
fulminating silver used in the small, 173
used against the Plantagenet, 522

Touch paper, 21, 292, 294, 370

Tourbillons, theory of, 16
cases for, 245
how charged, _ibid_
common, 358
mosaic, _ibid_
character of, 359
mosaic, composition of, 360
table, 361
appendages to, _ibid_
directions for firing, _ibid_
common, another mode of making, _ibid_
composition of, for different calibers, 362
for half inch caliber, _ibid_
of various sizes, _ibid_
general rule respecting, 363

Torches, odoriferous, 289
compositions for, _ibid_
used in war, 501
how made, 502

Tourteaux, 500
for what used, _ibid_
goudronné of the French, _ibid_
how made, _ibid_
composition for, according to Bigot, _ibid_
according to the Strasburg formula, 501

Tow and hemp, 222

Towering rocket, 340
theory of the, 16

Transparencies, 425

Tubes, cannon, how inflamed by sulphuric acid, 22

Tunestrick, his wonderful performance, 34
his miraculous liquor, 35

Turpentine, 146
for what purpose used in fire-works, _ibid_
spirit of, how inflamed by nitric acid, 51
decomposes the nitrates, 146
a component part of the ancient Greek fire, _ibid_
obtained from different species of the Pinus, _ibid_
common, from the Pinus Sylvestris, _ibid_
composed of resin and volatile oil, 147
Spirit of, how obtained, _ibid_
Essential oil of, _ibid_
Venice, from the Pinus laryx, 147
made artificially, _ibid_
from the Pinus Maritima, _ib._
spirits of, Morey's experiments with, 148

Turtle, the American, 515
invented by Bushnel, 516
intended to destroy shipping, _ibid_
outline of its construction, _ibid_
experiments with, 517
sergeant Lee's adventure with the, _ibid_

Turf, used in the place of spunk, 572
inflammability of, 152, 571
of morasses, some account of, _ibid_
Tacitus' account of, taking fire, _ibid_
Gmelin's observations on, _ibid_

Vapour of water accelerates combustion, 432
preparation of, to form blue flame, _ibid_

Varnish, 164

Variegated stars, 18

Vase, the scented, 288
composition for the, _ibid_

Vegetable poisons, their use in poisoning of arrows, 568

Venice turpentine, 147

Versailles, fire-works at, in 1739, 257

Vinegar from wood, character of the, 93
quantity of the, _ib._
apparatus for obtaining the, 95

Violet match, 325

Vitriol, blue, its use in fire-works, 222

Volcano of Lemery, 323
how made, _ibid_
theory of, _ibid_
exhibition of a, in China, 256

Volute, grand, 417

Wand, Mercury's, 401
fire, 400

War-rockets, 526
of the Asiatics, 262, 529

Water-squibs, 448
fire-fountain, _ibid_
balloons, odoriferous, 446
compositions for, _ibid_
mines, 444
fire-works, 442
rockets, 18, 443
of ammonia, 185
casks, the use of charring, 87
how preserved at sea, _ib._

Water, its presence in fire-works injurious, 8
weak, what, 64
strong, in nitre making, _ib._

Waterloo crackers, how made, 273

Watson, the Bishop of Llandaff, his mode of examining gunpowder, 141

Waved fire, 418

Wax, artificial, for candles, 51

Wheels, 19

Wheel cases, manner of loading, 237

Wheels, how made incombustible, 240

Wheel cases, standing and fixed, composition for, 388

Wheels, slow fire for, 389
dead fire for, _ibid_
single, vertical, &c. 391
plural, 393
illuminated spiral, _ibid_
balloon, 394
fruiloni, _ibid_
pin, 395
composition for, _ibid_
horizontal, how changed to vertical, with a sun in front, 399
cone, double illuminated, 416
vertical, on a horizontal table, _ib._
decoration of, 418
single, double, and triple table, 425
for water, horizontal, 444

White fire, composition for, 272, 580
flame lances, 315
composition of the, _ib._
iron of the French, what, 206
pitch, 147
Stars, 18

Whitening of cases, 370

Whirling serpents, 338

Wicks, lamp, of amianthus, 26
Kircher's, _ib._

Wild fire, 492

Will-with-the-Wisp, 85

Wings, 406

Women, Roman, their custom with fire, 37

Wood, charred, 90
carbonization of, how performed, _ib._
improved process for the, 91
kinds of, for making charcoal for gunpowder, 94
light, for gunpowder, _ib._
heavy, or hard, when used, _ib._
raspings of, used in fire-works, 163, 216
distillation of, 217
bronzing of, 242
ashes of, used in fire-works, 192
tubes of, used by the ancients in fire-works, 262
how preserved from the weather, 265
how made incombustible, 241
colouring of, how performed, _ibid_

Woolf, Arthur, his steam apparatus, 119

Wootz, 209

Worcester, the Marquis of, his destructive machines, 525

Works, detonating, 273

Workshop for artificers, 235

Wrought iron, 206

Xenophon, his account of ancient jugglers, 23

Yew tree, illuminated, 402

Yellow fever, supposed cause of, 61

Zoroaster, the followers of, in Persia, 386
sacred fire of the, _ibid_

Zinc, 196

THE END.

[Illustration]

DESCRIPTION OF THE PLATE.

FIG. 1.--A. is the entering rammer or driver. It is bored in such a
manner, that the whole of the broach, or piercer above the nipple,
n, may be admitted. The cavity of the bore is cylindrical, and
equal in diameter to that of the foot of the broach. This driver
serves to fix the rocket case, over the broach, in the mould G, and
to form the cup, o, fig. 10, for receiving the priming.

B. is the driver of the first charge. It is bored in such a manner,
as to admit the broach to within two-fifths of the interior
diameter of the case, from its base. Its bore is cylindrical, and
has the diameter of the broach, at the height of two-fifths the
interior diameter of the case.

C. is the driver of the second charge, and admits the broach
two-thirds of its length; the diameter of its bore being the same
as that of the broach, at one-third of its height.

D. is the driver of the third charge, and admits one-third of the
broach; the diameter of the bore being that of the broach, at
two-thirds of its height.

E. is the last driver, and is solid; the charge being above the
summit of the broach. See page 231.

FIG. 1. and FIG. 6.

FIG. 1. (cont.) and FIG. 6.--The broach or piercer I, fig. 1, (a
section of which is represented in fig. 6), is a truncated cone,
having a hemispherical summit. The cone is the part from a to b,
fig. 6. The diameter of the base of the cone at b, ought to be
two-fifths of the interior diameter of the case, and the diameter
at the summit, one-fifth, which is also the diameter of the small
hemisphere at the top. The height from b to a, ought to be seven
times the interior diameter of the case, or 17.5 times the diameter
of the base b. The part n, fig. 1, and from b to c, fig. 6, is
rounded. Its diameter ought to be that of the interior of the case,
and its height, seven-tenths of that diameter. This is called the
nipple, and is the part, which gives shape to the cup o, fig. 10.
The part m, fig. 1, and from c to d, fig. 6, is cylindrical, and
may be made of any height or diameter, provided the latter is not
less than that of the cone. It is generally one-twentieth more
than the exterior diameter. This part ought to penetrate into the
bottom of the charging mould, G, fig. 1, and fit closely, so as to
be firm. The part from d to e, fig. 6, is the blade or tongue of
the broach. It is rectangular, and enters into the block H, fig.
1, where it is firmly fixed. The size of this part is arbitrary, as
well as that of the block H, fig. 1.

FIG. 2.--The Rocket finished.

FIG. 3.--Conical Mandril or Former, for the head of the Rocket.

FIGS. 4 & 5.--Head of the Rocket and _Pot de fusée_.

FIGS. 7 & 8.--Mealing table and Mullar.

FIG. 9.--The Rocket case choaked, and prepared for charging.

FIG. 10.--Section of the Rocket, after charging.

FIG. 11.--The Rocket with its stick. For want of room, the stick is
represented in two pieces.