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Title: Quarterly Journal of Science, Literature and the Arts, July-December, 1827
Author: Various
Language: English
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THE
QUARTERLY JOURNAL
OF
SCIENCE,
LITERATURE, AND ART.
[Illustration: Royal Institution of Great Britain Emblem.]
JULY TO DECEMBER, 1827.
LONDON:
HENRY COLBURN, NEW BURLINGTON-STREET.
MDCCCXXVII.
CONTENTS.
_July—Oct._ 1827.
On the Beauties contained in the Ovals and in the elliptic
Curves, both simple and combined, generated from the same
Figure or Disk. By R. R. REINAGLE, Esq., R.A. 1
On the Art of forming Diamonds into Single Lenses for
Microscopes. By Mr. A. PRITCHARD. 15
Analysis of a newly-discovered Spring, at Stanley, near
Wakefield. By Mr. WILLIAM WEST. 21
Observations on the State of Naval Construction in this
Country. 25
On Malaria. No. II. By Dr. MAC CULLOCH, M.D., F.R.S., &c. 39
Dr. TURNER’s _Elements of Chemistry_, reviewed 60
Experiments on Audition. Communicated by Mr. C. WHEATSTONE. 67
On the Petromyzon Marinus 72
Observations upon the Motion of the Leaves of the Sensitive
Plant 76
Experiments on the Nature of LABARRAQUES’ Disinfecting Soda
Liquid. By M. FARADAY, F.R.S., Cor. Mem. Roy. Acad. Sci.
Paris, &c. 84
Hieroglyphical Fragments, with some Remarks on English
Grammar. In a Letter to Baron William Von HUMBOLDT. By a
Correspondent 92
Dr. MAC CULLOCH’s ‘_Malaria; an Essay on the Production and
Propagation of this Poison_,’ reviewed 100
Account of a New Genus of Plants, called _Reevesia_. By J.
LINDLEY, Esq., F.L.S., &c. &c. 109
ASTRONOMICAL AND NAUTICAL COLLECTIONS.
i. FRESNEL on the Undulatory Theory of Light 113
ii. Rule for the Correction of a Lunar Observation. By Mr.
W. WISEMAN, of Hull 135
‘_De l’Influence des Agens Physiques sur la Vie_. Par W. F.
EDWARDS, D.M.’ &c., reviewed 137
Account of Professor CARLINI’s Pendulum Experiments on Mont
Cenis 153
Analysis of ‘_Transactions of the Horticultural Society_.
Vol. vii. Part I.’ 159
_On the Recent Elucidations of Early Egyptian History_ 176
_Proceedings of the Horticultural Society_. 190
MISCELLANEOUS INTELLIGENCE.
I. MECHANICAL SCIENCE.
1 On the Combined Action of a Current of Air, and the
Pressure of the Atmosphere 193
2 Considerations relative to Capillary Action 194
3 Novel Use of the Plough 197
4 Discovery of Rocks under the Surface of the Sea 198
5 Paper to resist Humidity _ib._
6 Professor Amici’s Microscopes _ib._
II. CHEMICAL SCIENCE.
1 On the Specific Heat of Gases 200
2 On the Incandescence & Light of Lime 201
3 Evolution of Heat during the Compression of Water _ib._
4 On Electrical Excitation _ib._
5 Magnetic Repulsion 202
6 Diminished Solubility of Substances by Heat _ib._
7 Composition of Cyanic Acid 203
8 Iodous Acid 204
9 Manganesic Acid _ib._
10 Heavy Muriatic Ether, and Chloric Ether _ib._
11 Test for the Presence of Nitric Acid 205
12 Peculiar Formation of Nitre _ib._
13 Experiments on Fluoric Acid and Fluates _ib._
14 Crystallization of Phosphorus 206
15 Solution of Phosphorus in Oils _ib._
16 On the Inflammation of Powder, when struck by Brass 207
17 Cementation of Iron by Cast Iron _ib._
18 On the Preparation of Ferro-prussiate of Potash _ib._
19 Sulphocyanide of Potassium in Saliva 208
20 Decomposition of Sulphate of Copper, by Tartaric Acid
_ib._
21 Separation of Arsenic from Nickel, or Cobalt 209
22 Chemical Researches into Certain Ancient Substances 209
23 Compounds of Gold 210
24 On the Bitter Substance produced by the Actions of Nitric
Acid on Indigo, Silk, and Aloes _ib._
25 On the Existence of Crystals of Oxalate of Lime in Plants
214
26 Fallacy of Infusion of Litmus as a Test _ib._
27 Tests for the Natural Colouring Matter of Wine 215
28 Test of the Presence of Opium _ib._
29 Denarcotized Laudanum _ib._
30 Extraction of Morphia from Dry Poppy Heads 216
31 Preparation of Morphia _ib._
32 Easy Method of Obtaining Meconic Acid 217
33 On a New Vegetable Acid _ib._
34 Altheine, a New Vegetable Principle _ib._
35 Rheine, a New Substance from Rhubarb 218
36 On Dragon’s Blood, and a New Substance which it contains
_ib._
37 Purification of Madder 219
38 On Indigo, and Indigogene 220
39 On the Mutual Action of Ethers, and other Substances 221
40 Faraday’s _Chemical Manipulation_ _ib._
III. NATURAL HISTORY.
1 On the Supposed Influence of the Moon 222
2 Luminous Appearances in the Atmosphere _ib._
3 On the Determination of the Mean Temperature of the Air 223
4 Indelible Writing _ib._
5 Peculiar Crystals of Quartz _ib._
6 Native Iron not Meteoric 224
7 Native Argentiferous Gold 225
8 Prothéeïte, a New Mineral 226
9 Volcanic Bisulphuret of Copper _ib._
10 Fall of the Lake Souwando, in Russia 227
11 Vegetable Torpor in the Root of the Black Mulberry Tree
228
12 Method of increasing the Odour of Roses _ib._
13 Pine Apples _ib._
14 Mode of Condensing Vegetable Substances for Ship’s
Provisions 229
15 Rewards for the Discovery of Quinia, and for Lithotrity
_ib._
16 Upon the Gaseous Exhalations of the Skin 230
17 Effects of Galvanism in Cases of Asphyxia by submersion
_ib._
18 Recovery from Drowning 231
19 Preservation of Cantharides _ib._
20 Chloride of Lime in cases of Burns _ib._
21 Cure of Nasal Polypi 232
22 Bite of the Viper _ib._
23 Experiments on the Poison of the Viper _ib._
24 Destruction of Moles _ib._
25 On growing Salad Herbs at Sea 233
26 Chinese Method of Fattening Fish 234
Meteorological Diary for the Months of June, July,
and August, 1827 236
CONTENTS.
_Oct.–Dec._ 1827.
On the Means generally used with the Intention of curing a
Stoop. By the late Mr. SHAW 237
A Critique on the Aplanatic Object-glasses, for diverging
Rays, of Vincent Chevalier, ainé et fils. By C. R.
GORING, M.D. 248
On the Existence of Chlorine in the Native Black Oxide of
Manganese. By JOHN M’MULLEN, Esq. 258
Modern Improvements of Horticulture 261
FARADAY’s _Chemical Manipulation_, reviewed 275
Statistical Notices suggested by the actual State of the
British Empire, as exhibited in the last Population Census.
Communicated by Mr. MERRITT 283
On the Modern Ornaments of Architecture, &c. 292
_De l’Influence des Agens Physiques sur la Vie_. Par W. F.
EDWARDS, D.M. &c., reviewed 296
Experiments on Thought 308
Hieroglyphical Fragments, illustrative of Inscriptions
preserved in the British Museum, with some remarks on Mr.
Champollion’s opinions. In a letter to the Cav. San Quintino
310
On the Naturalization of Fish. By J. MAC CULLOCH,
M.D., F.R.S., &c. 320
WADD’s _Nugæ Chirurgicæ or, a Biographical
Miscellany_, reviewed 329
_Nugæ Canore, by_ UNUS QUORUM, reviewed _ib._
WADD’s _Mems., Maxims, and Memoirs_, reviewed _ib._
On Tic Douloureux 346
Remarks on some Quadrupeds supposed by Naturalists to be
extinct. By JOHN RANKING, Esq. 350
Description of a cheap and portable Instrument for enabling
Young People to acquire a knowledge of the Stars, or determine
their situation in the Heavens. By S. LEE, Esq. 371
CARUS’s _Introduction to the Comparative Anatomy of
Animals_, reviewed 377
_Comparative Value of the principal Varieties of Fuel, &c.,
by_ MARCUS BULL, reviewed _ib._
DANIELL’s _Meteorological Essays and Observations_,
reviewed _ib._
_Philosophical Transactions of the Royal Society for 1827_,
reviewed _ib._
_Practical Treatise on the use of the Blowpipe, by_ J.
GRIFFIN, reviewed _ib._
_Circle of the Seasons, and Practical Key to the Calendar and
Almanack_, reviewed _ib._
_Conversations on the Animal Economy_—reviewed _ib._
Notice of a New Genus of Plants discovered in the Rocky
Mountains of North America by Mr. DAVID DOUGLAS. By
JOHN LINDLEY, Esq. 383
A Description of the Aurora Borealis seen in London on the
Evening and Night of the 25th of September, 1827, with
Critical Remarks, &c. By E. A. KENDALL, Esq., F.S.A.
385
Proceedings of the Royal Society 424
Proceedings of the Horticultural Society 425
ASTRONOMICAL AND NAUTICAL COLLECTIONS
i. Ephemeris of the periodical Comet for its Return in 1828,
computed with the consideration of a resisting Medium. By
Professor ENCKE 428
ii. Elementary View of the undulatory Theory of Light. By
Mr. FRESNELL 431
iii. Remarks on the action of Corpuscular Forces. In a
letter to Mr. POISSON 448
iv. Calculations of Lunar Phenomena. By THOMAS
HENDERSON, Esq. 450
MISCELLANEOUS INTELLIGENCE.
I. MECHANICAL SCIENCE.
1 On the Adhesion of Screws 453
2 Improvement in Steam-engines _ib._
3 Improved Clock 454
4 Method of dividing Glass by Friction _ib._
5 Use of Soapstone in diminishing Friction 455
6 On peculiar Physical Repulsions _ib._
7 On the Magnetic Effects of Metals in Motion 456
8 Duration of the Effects of Light upon the Eye 457
9 On the Measurement of the Intensity of Light _ib._
10 On the apparent Decomposition of White Light by a
Reflecting Body when in Motion 458
11 On the Barometer _ib._
12 Easy method of reducing Barometrical Observations to a
Standard Temperature _ib._
13 Diamond Lenses 459
14 Sapphire Lenses for Single Microscopes _ib._
15 On a Method of securing and Preserving the Rowing Pins in
Boats 460
16 Cold Injection for Anatomical Preparation 461
II. CHEMICAL SCIENCE.
1 Extraordinary Experiments on Heat and Steam 461
2 On the Use of feeble Electric Currents, for effecting the
Combination of numerous Bodies 462
3 Crystallization of Metallic Oxides 465
4 On Bromine _ib._
5 Elementary Nature of Bromine _ib._
6 Quantity of Bromine in Sea-Water 466
7 Sale of Bromine _ib._
8 Preparation of Iodous Acid _ib._
9 On a peculiar Nitric Acid, and Sulphate of Potash 467
10 On certain Properties of Sulphur 468
11 On the Fluidity of Sulphur and Phosphorus at common
temperatures 469
12 Separation of Selenium from Sulphur 470
13 On a new Compound of Selenium and Oxygen—Selenic Acid 471
14 Preparation of Hyposulphuric Acid 473
15 Singular Habitude of Phosphoric Acid with Albumen 473
16 Economical Preparation of Deutoxide of Barium 474
17 Preparation of Aluminum—Chloride of Aluminum _ib._
18 Mutual Action of Lime and Litharge 475
19 New Chloride of Manganese discovered _ib._
20 Preparation of pure Oxide of Zinc 476
21 Deuto-Sulphuret of Cobalt _ib._
22 Separation of Bismuth from Mercury by Potassium _ib._
23 Sulphuret of Arsenic proportionate in Composition to
Arsenic Acid _ib._
24 New Double Chromates 477
25 Dobereiner’s finely divided Platina 477
26 New Metals 478
27 Analysis of Porcelain Pottery, &c. _ib._
28 On the Composition of simple Alimentary Substances 480
29 Preparation of Sulphate of Quinia and Kinic Acid, without
the use of Alcohol 482
30 Pure Narcotine prepared 483
31 Uncertain Nature of Jalapia _ib._
32 Preparation of pure Mellitic Acid
33 On a New Acid existing in Iceland Moss 484
34 Remarks on the Preparation of M. Gautier’s
Ferro-prussiate of Potash, as described in this Journal for
July, 1827 _ib._
III. NATURAL HISTORY.
1 Squalls of Wind on the African Shores 486
2 Destruction of an Oak by Lightning 487
3 Description of a Meteoric Fire-Ball seen at New Haven _ib._
4 Remarkable Meteoric Phenomenon 488
5 Aurora Borealis seen in the Day-time at Cannonmills 489
6 Aurora Borealis in Siberia _ib._
7 On the Presence of Ammonia in Argillaceous Minerals _ib._
8 Composition of Apatite 490
9 Burmese Petroleum Wells _ib._
10 Direction of the Branches of Trees _ib._
11 Effects of Light on Vegetation _ib._
12 Organization and Reproduction of the Trufle 491
13 Alteration of Corn in a subterraneous Repository 492
14 Quick Method of putting Insects to Death 493
15 Destruction of Snails by common Salt _ib._
16 Remarkable Hairy Man _ib._
17 Application of Remedies by Absorption from the Surface
_ib._
18 On the Strix Cunicularia, or Coquimbo Owl 494
19 Naturalization of Fish 496
20 Mode of keeping Apples _ib._
21 On the Cultivation and Forcing of Sea Kale 497
Meteorological Table 500
TO OUR READERS AND CORRESPONDENTS.
The drawings, illustrating the construction of a Blow-pipe, are not
sufficiently accurate to enable us to publish them. Our Correspondent
will observe that we have noticed another part of his letter.
We regret that we are unable to offer our Correspondent, upon the
subject of _Gas Works_, any precise information. There can be no
doubt that an atmosphere tainted by coal gas is injurious to animal
and vegetable life, but much will depend upon the extent of the
contamination, and other causes, of which our limits prevent mention.
To say nothing of danger from fire and from explosion, it has always
been matter of surprise to us that gas-works are tolerated by the
government in close and confined situations—that the Thames is
suffered still to be polluted with their offal, and that they are
sometimes placed close by the road side, (as at Brentford,) to the
nuisance of every one who passes. These matters want looking into.
Q. will find an answer to his question, in the “Gazette of Health”
for last July.
F. R. S. must remain unanswered till after St. Andrew’s Day.
Dr. Heinecken’s paper is disposed of as he desired.
Mr. BRANDE and Mr. FARADAY will commence their Lectures and
Demonstrations in Theoretical and Practical Chemistry, in the
Laboratory of the Royal Institution, _on Tuesday, the 9th of
October_, at Nine in the Morning precisely. Further particulars,
and a Prospectus, may be obtained at the Royal Institution, 21,
Albemarle-street, or by application to the Lecturers.
_In the Press_—A COLLECTION OF CHEMICAL TABLES, for the use of
Students, in Illustration of the Theory of Definite Proportionals, in
which are shewn the Equivalent Numbers of the Elementary Substances,
with the Weights and Volumes in which they combine, together with the
Composition of their most important Compounds, and the Authorities
for their Analysis. By WILLIAM THOMAS BRANDE.
THE
QUARTERLY JOURNAL
OF
SCIENCE, LITERATURE, AND ART.
JULY—OCT. 1827.
_On the Beauties contained in the Oval, and in the Elliptic Curves,
both simple and combined, generated from the same Figure or Disk_.
By R. R. Reinagle, Esq., R.A.
Being the subject of a Discourse delivered at the Royal Institution
of Great Britain.
After an apposite discourse to introduce the subject, the first
course taken, was to demonstrate the advantages of understanding the
right use of geometrical terms in our descriptions of the varieties
of shape, both in nature and art.
Every thing deserving the title of beautiful, and every grand object,
assume an outline of definite character: these are to be found in the
different classes of geometrical figures; the former in undulating
lines of elliptic curves, and grandeur in angular dispositions of
figure. All motion assumes a curved direction[1]. The primary and
leading object of the discourse was to prove the fact of original
beauty: and that a curved line was beautiful in an abstract point
of view, free from all associations. For this purpose there were
designed many diagrams on large black painted boards. [p002]
The explanation commenced with six or more parallel lines at equal
distances, and equal length, in an horizontal position to the eye of
the audience, _Fig._ 1; and another set of the same number of lines
drawn perpendicular, _Fig._ 2: these were demonstrated to possess not
the slightest character or principle of beauty in them, either as
separate lines, or collectively, however many.
[Illustration: _Fig._ 1.]
[Illustration: _Fig._ 2.]
[Illustration: _Fig._ 3.]
[Illustration: _Fig._ 4.]
The next diagram consisted of six or more radiating lines from
a centre, _Fig._ 3, and a corresponding number in an horizontal
direction, but of unequal quantities; they diminished like a flight
of steps, _Fig._ 4. It was then shown that the first means of
combining the six or more lines, which had been first drawn, so as
to please the eye, without creating any geometrical figure, was the
radiating principle. Our eye not only can tolerate that union of
lines, but receive the impression as pleasing in character; while all
lines parallel to each other, being right [p003] lines, and viewed
as a flight of steps, or pile of planks, opposite the observer, are
disagreeable. Upon the former principle it is, that the rays of the
sun, and rays of light generally, are so attractive and beautiful.
It is from this circumstance that right lines drawn in an inclined
position to the plane of the picture, derive an interest from the
angles engendered through the imagination.
[Illustration: _Fig._ 5.]
[Illustration: _Fig._ 6.]
[Illustration: _Fig._ 7.]
[Illustration: _Fig._ 8.]
To follow up the principle by regular steps, and to open a clear
view of the laws of beauty in lines, there were traced some inclined
right lines (_Fig._ 5), with a regular set of right angles upon it,
like the stems of leaves on each side. This exhibited no sort of
beauty, nor any other advantage than mere combinations of formal
angles. The next diagram (_Fig._ 6) was an inclined line as before,
with similar angular projecting stems, to which were added elliptic
curves on the upper side of each branch, that produced the form of a
leaf. _Fig._ 7 was another inclined line, having oval curves upon it.
Both these were shown to possess principles approaching to beauty, by
progressive advances in combination and original structure. _Fig._ 8
was an inclined line with the oval curves upon it; to which a similar
addition of elliptic curves were adjoined to the stems, [p004] as in
_Fig._ 6. This addition made a new advance towards beauty. _Fig._
9 commenced a more perfect principle of beauty, having an elliptic
stem with oval branches rising from it, as in the others. If to this,
the principle of gradation had been given, the eye would prefer it;
I mean, by a scale of increase from the top to the bottom of the
projecting stems: and if there had been superadded the external
contour of a lengthened egg, like the form of a sage leaf, we should,
step by step, advance into the region of beautiful character of
exterior shape. _Fig._ 10 is a retrograde, showing how uncongenial
angular forms are to curved lines, when producing ornament; at
least how little our eye can bear the angular projections from the
elliptic or oval turned stem. _Fig._ 11 was a curve of exactly the
same disk, with the same oval stems, to which a small serpentine
addition was made, expressing a leaf. Of all the last seven diagrams,
this abounded with the greatest portion of beautiful lines, and is
indisputably the most agreeable and beautiful. Combinations are like
numericals; many of these forms, placed together with judgment and
discretion, will attract us from the larger proportion of beauty
that meets the eye at once, like a head of beautiful hair: one hair,
however gracefully bent, cannot impress us like an entire lock of
the hair; nor will this [p005] curl charm us as the whole will on
the human head. We owe to construction and combination all our
pleasurable feelings of beauty: no person is allured by a single
feature of any species of objects: but a thousand, or a million,
arouses our anxious notice. Thus, the last diagram of the elliptic
stem and the foliage upon it, exhibited, by the continuity of curved
lines, the greatest approach to beauty, of all the figures presented
to the notice of the audience.
[Illustration: _Fig._ 9.]
[Illustration: _Fig._ 10.]
[Illustration: _Fig._ 11.]
[Illustration: _Fig._ 12.]
These preliminary designs opened the way for richer combinations; but
the subject affording such an immense field of variety, I confined
myself to the narrowest limits, and to one oval disk of seven inches
transverse diameter, from which seven different designs were shown on
paper. The first had a variety of serpentine lines placed at random,
all produced by the disk of the oval just named, and the confluent
lines of two such, placed side by side, or end to end, _Fig._ 12;
which oval disk was put upon the lines to prove the construction.
These lines, without expressing or forming any sort of figure,
exhibit a set of elegant curves, of varied quantities of convex and
concave, with which our eye will be more pleased than any set of
right lines similarly distributed, as in _Fig._ 13, which follows.
[p006]
[Illustration: _Fig._ 13.]
[Illustration: _Fig._ 14.]
Two other diagrams were placed before the company, each a circle of
12 ovals, from the same disk, revolved upon an axis, resting upon one
end of the transverse diameter, (the length-ways of the oval,) which
figure in the skeleton was a duodecagon. _Fig._ 14 is one of the
diagrams; the ovals folding regularly over each other. By suppressing
the continuity of the oval disk, where the lines would traverse, a
very pleasing figure [p007] is created. It may be easily converted
into foliage, and can be amazingly varied in principle, by having
fewer ovals, and making them revolve upon an arm or continuation of
a line from the transverse diameter. _Fig._ 15 is the same diagram,
with all the oval lines described, which forms a figure of elegant
intricacy; each member, or curvilinear subdivision, assumes a most
agreeable shape: the whole, at the first sight, does not carry the
evidence of being generated from the same disk. These agreeable
figures may be varied to an extraordinary extent: the two that were
presented were mere examples of some of the numerous changes that any
given oval disk may create.
[Illustration: _Fig._ 15.]
[Illustration: _Fig._ 16.]
[Illustration: _Fig._ 17.]
The objects next presented, were three vases of very dissimilar
appearance, all produced from the same diagram of the oval; each in
a separate drawing. The first was like a Greek vase with handles;
its character established by employing certain proportions of
quantities, in seven parts. The body has four parts, the foot or
pedestal one; the neck two. The handles were regulated in the
position and projection by lines drawn from the bottom of the vase,
through the ovals which compose the outline of the two sides; and
passing through the transverse diameter. These handles were made
from an oval that was the length of half the line of the transverse
diameter, _Fig._ 16. The skeleton of angles that [p008] govern the
shape of this vase, is a very pretty figure of itself. The form does
not proceed from any caprice of irregularity, but is consistent
with rational organization, and symmetrical proportions. The figure
of the plate sufficiently describes the mode of making the diagram
without entering into the detail. _Fig._ 17 represents a tazza with
handles: the same disk is apparent, by the dotted lines that made the
first vase. The ovals [p009] are placed right and left of a central
perpendicular line, dividing the cup in two parts; the transverse
diameters meet in one line parallel to the base of the tazza; a
dotted outline expresses the angular position of the handles: the
concave lip of the tazza is made by the same oval disk, whose
transverse diameter leads to the under line of the folding edge of
the cup. The leg of the tazza is produced by the same small disk
that served for the handles of the first vase. The body of the vase
and the leg form two equal parts; the whole upper extent ought to be
seven parts, so that it is seven and two[2]; the width of the base
of the leg measures two parts, and the altitude three, of the seven
parts. These proportions cannot produce any other than agreeable
appearances, apply them as we may.
[Illustration: _Fig._ 18.]
The third vase, exhibited an Hebe cup, with a handle, which presented
a totally different appearance in form to the two previous ones. It
was proportioned by similar principles: the larger disk made the
body, inclined right and left upon the end of the oval. The neck and
the leg were both made from the smaller oval disk; the dotted lines
to the ovals of the leg sufficiently show the fact. The handle and
concave lip of the cup were made by an application of the same disk.
The altitude contained four parts. The body two parts, the leg one
part, and the neck one other part; the handle rises one-eighth above:
every portion of this figure is created by the two disks previously
named. The foliage rises from below and descends from above,
one-fourth of the whole height of the body [p010] to the commencement
of the concavity of the neck, where the beading runs round.
I remarked, that by adhering to regular proportional quantities of 1
and 2, 3 and 5, 2 and 5, 7 and 5, 7 and 2, &c., and using elliptic
disks or curves, very great beauties are derived.
[Illustration: _Fig._ 19.]
[Illustration: _Fig._ 20.]
A skeleton of the tazza in angles was drawn on a black painted board,
together with oval disks placed upon those lines, which clearly
demonstrated the whole system of the construction. The explanation
of these various diagrams necessarily involved a circumstantial
description of each created figure, which were thoroughly analysed.
Quantity and variety were particularly dwelt upon, as absolutely
necessary to the production of perfect beauty; equalities being
unfriendly to that symmetry which accords with nature. Some other
diagrams were drawn, to show the inelegant appearance of radiating
lines from the concave or convex half of an oval or an ellipse,
_Fig._ 19: but by drawing another convex half of an oval, and placing
those lines as tangents, greater beauty was formed by the alternate
changes and varieties of inclination of each tangent, _Fig._ 20. This
was capable of an immediate adaptation to elegant vegetation; [p011]
a few convex and concave elliptic curves added to each tangent,
produced an ear of barley, or an ear of rye, the elegant construction
of which, is rarely noticed in our remarks on nature, _Fig._ 21.
[Illustration: _Fig._ 21.]
The discussion on these various designs being concluded, some
important compositions of three great and renowned painters were
produced, to corroborate what had been advanced in support of the
native beauty of the oval and ellipse. Raphael’s grand composition of
the dispute on the Sacrament is in three grand oval curves.
The Doctors of the Church on the ground plan are ranged in an oval
convex line; and the heavenly Choirs engage two concave oval shapes
of the same proportion, but of unequal quantities. This is also a
proof of a composition of parts, bearing two to one.
The facility of expressing such a composition, by being geometrical,
is extremely easy.
The second illustration was the Aurora, by Guido, of the Aldobrandini
palace. This was pointed out to depend upon an oval curve, and
continued curvilinear details: the striking beauty of this fine
composition is owing to its great and simple elliptic curve, which
includes the whole group; the attendant hours have the principle of
radiating to a centre of the oval: thus harmonizing and uniting forms
congenial both to principle and nature.
The third grand composition was by Rubens, the Coronation ceremony of
Mary de Medicis, one of the grand Luxemburg pictures.
This very fine composition is contained in an oval concave [p012]
curve, and the figures in several points radiate to a centre. Some
of the group pass the great leading line, but only to the degree
and with the licence that a genius can effect, which destroys the
too great, and the too palpable construction of the composition.
The allegorical figures of Fame and Genius hovering over the royal
personage, establish a centre to the oval, which prevents a void that
would have been weak in the composition.
Three designs were next produced from Etruscan vases, to carry
the evidence further, and to show the original source of the
demonstrations of beauty in Grecian art. One was a charioteer driving
a pair of magnificent horses of the highest spirit, _Fig._ 22. The
composition is elliptic, and serpentine within.
[Illustration: _Fig._ 22.]
The youthful conductor of the steeds is in a crescent or boat-shaped
car, and his form is elegantly bent to meet the action and motion;
his mantle flows behind in curved and serpentine folds, expressing
the wind occasioned by the velocity of action. A more graceful or
beautiful group and composition cannot be imagined.
The next design was a female in an elegant and very gentle serpentine
action of the figure. Every portion of the outlines was elegant,
from the varied succession of convexity and concavity; not a single
angle could be traced throughout the whole [p013] of this beautiful
creature. She held in her left arm a very handsome oval vase; and in
the other a sort of scarf with ribands, all serpentine in form. By
her side is placed a young man selected from another Etruscan design.
[Illustration: _Fig._ 23.]
The line of this figure was the outline of an ellipse; it is
perfection in every respect; and the grace was shown to depend upon
gentle curved lines of convex and concave, alternately blended, and
confluent. The motion of ships at sea is described in gentle elliptic
curves; the wings and plumage of birds assume the oval and elliptic
curves; all the fibres of their feathers have that form; some
flattened, others more rounded: the pine-apple and numberless fruits
have all an oval character of outline.
Many take the character of eggs, pointed at one end, and large and
blunt at the other extremity. The leaves of trees [p014] have the
oval shape more than any other; the bend of the branches, and the
whole external form of many trees is oval.
There is no form of created things which may not be found to
correspond in all its dependent shapes to ovals and ellipses of
various disks, even objects which at first sight seem to contradict
the possibility of meeting this system.
The lecture was closed by some extracts and quotations from Lomazzo,
Dryden, Hogarth, Du Fresnoy, and the Abbé du Bos; the tendency
of which was to show that lines had been mentioned, and had been
written upon without any explanation given that could lead to certain
conclusions. That all these authors attributed to supreme genius
alone, and something of the divinely inspired character in artists,
the power to produce those indescribable lines that affect the human
eye so strongly. These lines I described as belonging to the oval and
the ellipsis, and the confluent lines by conjunction and combination;
that these indescribable lines, which from Plato to Dryden had never
been detected or obtained a name; that puzzled all equally alike, are
those alone I attempted, and I believe proved in this lecture, to be
the elliptic combinations.
I stated that the great Greek artists confined themselves to certain
rules and principles of unerring consequences in the production
of beauty, grace, or grandeur in their figures; that all their
compositions depended upon the same species of rule and order. I
pointed out, that fashion is in all countries the destroyer of
taste, that it unfits the mind for fixed principles; that where it
dominates, _there_ taste will be always fluttering and never settle,
nor have a sure dominion. The Greeks, having no such vile tormentor
to divert them from a pure course in their progress, arrived at the
summit of perfection in every scientific pursuit, by following sure
principles as their guides, and by never abandoning a path traced by
nature, and matured by the most sublime philosophy.
FOOTNOTES:
[1] A great number of geometrical diagrams were exhibited, from a
single line, to angles, squares, oblongs, circles, ovals, cones,
cylinders, spiral lines, and various serpentine lines, &c.
[2] The whole extent of the tazza, including the projection of the
handles, should be seven parts; and the height of the vase two of
such seven parts.
[p015]
_On the Art of forming Diamonds into single Lenses for
Microscopes_.—By Mr. A. Pritchard.
[Communicated by Dr. GORING.]
Of the various improvements in Microscopes originated by Dr. Goring,
that which he conceives to be the most important is the construction
of single magnifiers from adamant. The details relative to this novel
class of instruments, I have been induced to lay before the public.
Single microscopes naturally aplanatic, or at least sufficiently so
for practical purposes, possess an incontestable superiority over
all others, and must be recognised by the scientific as verging
towards the ultimatum of improvement in magnifying glasses. The
advantages obtained by the most improved compound engiscopes over
single microscopes resolve themselves into _the attainment of vision
without aberration with considerable angles of aperture_; but against
this must be set the never-to-be-forgotten fact, that they only show
us a _picture of an object instead of nature itself_; now a Diamond
Lens shows us our real object without any sensible aberration like
that produced by glass lenses; and we are entitled, I think, to
expect new discoveries in miscrosopic science, even at this late
period, _from very deep single lenses of adamant_[3]. I shall not
fatigue my [p016] readers by describing the difficulties which were
encountered in the prosecution of the design of making diamond
lenses. Nature does not seem to permit us to produce any thing of
surpassing excellence without proportional effort, and I shall simply
say, that in its infancy the project of grinding and polishing the
refractory substance of Adamant was far more hopeless than that of
making achromatic glass lenses of 0.2 of an inch focus. I conceive it
just to state that Messrs. Rundell and Bridge, of Ludgate-hill, had,
at the time of the commencement of my labours, many Dutch diamond
cutters at work, and that the foreman, Mr. Levi, with all his men,
assured me, that it was impossible to work diamonds into spherical
curves; the same opinion was also expressed by several others who
were considered of standard authority in such matters.
Notwithstanding this discouragement, in the summer of the year 1824,
I was instigated by Dr. Goring (at his expense) to undertake the
task of working a diamond lens: (being then under the tuition of Mr.
C. Varley, who was however at that time absent.) For this purpose,
Dr. G. forwarded to me a brilliant diamond, which, contrary to the
expectation of many, was at length ground into a spherical [p017]
figure, and examined by Mr. Levi, who expressed great astonishment
at it, and added that he was not acquainted with any means by which
that figure could have been effected: unfortunately this stone was
irrecoverably lost. Mr. Varley having returned from the country,
becoming now thoroughly heated with the project, permitted me to
complete another diamond, which had been presented to me by Dr. G.:
this is a plano-convex of about the 1/20th of an inch focus: it was
not thought advisable to polish it more than sufficed to enable us
to see objects through it, because several flaws, before invisible,
made their appearance in the process of polishing. In spite of all
its imperfections, it plainly convinced us of the superiority which
a _perfect diamond lens_ would possess by its style of performance,
both as a single magnifier and as the object lens of a compound
microscope. After the completion of my articles with Mr. V., being
entirely under my own command, I devoted some time to the formation
of a perfect diamond lens, and have at length succeeded in completing
a double convex of equal radii of about 1/25th of an inch focus,
bearing an aperture of 1/30th of an inch with distinctness on opaque
objects, and its entire diameter on transparent ones; it was finished
at the conclusion of last year. The date of its final completion
has by many been considered a remarkable epoch in the history of
the microscope, being the first perfect one ever _made_ or thought
of in any part of the world[4]. I think it sufficient to say of
this adamantine lens that it gives vision with a trifling chromatic
aberration, but in other respects exceedingly like that of Dr. G.’s
Amician reflector, but without its darkness: for it is quite evident
that its light must be superior to that of any compound microscope
whatever, acting with the same power and the same angle of aperture.
The advantage of seeing an object _without aberration_ by [p018]
the interposition of but a single magnifier, instead of looking at
a picture of it (however perfect) with an eye-glass, must surely be
duly appreciated by every person endowed with ordinary reason. It
requires little knowledge of optics to be convinced that the simple
unadulterated view of an object must enable us to look farther into
its real texture, than we can see by any artificial arrangement
whatever; it is like seeing an action performed instead of a scenic
representation of it, or being informed of its occurrence by the most
indisputable and accurate testimony.
Previous to grinding a diamond into a spherical figure, it is
absolutely necessary that it should be ground flat, and parallel
on both sides (if not a Laske or plate diamond), so that we may be
enabled to see through it, and try it as opticians try a piece of
flint glass: without this preparatory step, it will be extremely
dangerous to commence the process of grinding, for many diamonds
give a double, or even a species of triple refraction, forming
two or three images of an object; this polarization of the light,
arising from the primitive form of the crystal, of course totally
unfits them for making lenses[5]. I need not observe, that it must
be chosen of the finest water, and free from all visible flaws when
examined by a deep magnifier. It was extremely fortunate for diamond
lenses that the first made was free from the defect of double vision,
otherwise diamonds _en masse_ might at once have been abandoned as
unfit for optical purposes. The cause why some stones give single
vision, and others several peculiar refractions, may also arise
from different degrees of density or hardness occurring in the same
stone. Diamond-cutters are in the habit of designating stones male
and female, sometimes a _he_ and _she_ (as they have it) are united
in the same gem,—their _he_ means merely a hard stone, and their
_she_ a soft one. When a diamond which will give several refractions
is ground into a spherical figure and partially polished, it is seen
by the microscope to exhibit a [p019] peculiar appearance of an
aggregation of minute shivery cristallized flaws, sometimes radiated
and sometimes in one direction, which can never be polished out:
I believe I could disstinguish with certainty a bad lens from a
good one by this phenomenon without looking through it[6]. Precious
stones, from their crystalized texture, are liable to the same
defects for optical purposes as diamonds.
Having ascertained the goodness of a stone it must next be prepared
for grinding; it will in many cases be advisable to make diamond
lenses plano-convex, both because this figure gives a very low
aberration, and because it saves the trouble of grinding one side
of the stone. It must never be forgotten, that it may be possible
to neutralize the naturally low spherical aberration of a diamond
lens by giving it an improper figure, or by the injudicious position
of its sides in relation to the radiant. When the lens is to be
plano-convex, cause the flat side to be polished as truly plane as
possible, without ribs or scratches; for this purpose the diamond
should be so set as to possess the capability of being turned round,
that the proper direction with respect to the laminæ may be obtained:
when the flat side is completed, let the other side be worked against
another diamond, so as to be brought into a spherical figure by the
abrasion of its surface. When this is accomplished, a concave tool of
cast iron must be formed of the required curve in a lathe, having a
small mandril of about 2/10ths of an inch in diameter, and a velocity
of about 60 revolutions per second! The diamond must now be fixed
by a strong hard cement (made of equal parts of the best shell lac
and pumice-stone powder, carefully melted together without burning)
to a short handle, and held by the fingers against the concave tool
while revolving. This tool must be paved by diamond powder, hammered
into it by an hardened steel convex punch: when the lens is uniformly
ground all over, very fine sifted diamond-dust carefully washed in
oil must be applied to another iron concave tool (I may here remark,
that of all the metals which I have used for this purpose soft cast
iron is decidedly to be preferred): this tool must [p020] be supplied
with the finest washed powder till the lens is completely polished.
During the process of grinding, the stone should be examined by a
magnifying lens, to ascertain whether the figure is truly spherical;
for it sometimes will occur that the edges are ground quicker than
the centre, and hence it will assume the form of a colloid, and thus
be rendered unfit for microscopic purposes.
The spherical aberration of a diamond lens is extremely small, and
when compared with that of a glass lens the difference is rendered
strikingly apparent. This diminution of error in the diamond arises
from the enormous refractive power possessed by this brilliant
substance, and the consequent increase of amplification, with _very
shallow curves_. The longitudinal aberration of a plano-convex
diamond lens is only 0.955; while that of a glass one of the same
figure is 1.166; both numbers being enumerated in terms of their
thickness, and their convex surfaces exposed to parallel rays. But
the indistinctness produced by lenses, arises chiefly from every
mathematical point on the surface of an object being spread out into
a small circle; these circles, intermixing with each other, occasion
a confused view of the object. Now this error must necessarily
be in the ratio of the areas of these small circles, which being
respectively as the squares of their diameters, the lateral error
produced by a diamond lens will be 0.912; while that of a glass lens
of like curvature is 2.775; but the magnifying power of the diamond
lens will be to that of the glass as 8 to 3, their curves being
similar; (or, in other words, the superficial amplification of an
object; with the perfect diamond lens before mentioned, is 22500
times, while a similar magnifier, made of glass, amplifies only 3136
times, reckoning 6 inches as the standard of distinct vision:) thus
the diamond will enable us to gain more power than it is possible to
procure by lenses of glass, for the focal distance of the smallest
glass lens which can be well made is about the 1/80th of an inch,
while that of a diamond, worked in the same tools, would be only the
1/200th of an inch.
If we wish to compare the aberrations of the two lenses when of equal
power, the curvature of the glass must be increased; and as it is
well known the lateral aberration increases inversely as the square
of the radius, (the aperture and position remaining [p021] the same,)
the aberration of the diamond lens will only be about 1/20th of that
produced by the glass one, even when their thickness is the same; but
as the curvature of the diamond is less, the thickness may be greatly
diminished.
The chromatic dispersion of the adamant being nearly as low as that
of water, its effects in small lenses can barely be appreciated by
the eye, even in the examination of that valuable class of test
objects, which require enormous angles of aperture to be rendered
visible, which it is evident must be of easier attainment by diamond
magnifiers than by any other sort of microscope.
A mathematical investigation of the spherical aberration of the
diamond when formed into lenses, I hope to lay before the public at
a future opportunity. The comparative numbers here taken from the
longitudinal aberration are, I believe, sufficiently accurate for
practical purposes.
_18, Picket-Street, Strand_.
FOOTNOTES:
[3] It seems generally admitted that, within a certain range of
power not exceeding that of a lens of 1/20th of an inch focus,
the beauty and truth of the vision given by the new compound
microscopes cannot be equalled by that of any single instrument,
at least of glass. It is no less true, however, that the _picture_
of the compounds, however perfect, is not like a real object, will
not admit of amplification beyond a certain point with advantage.
Under the action of very deep eye-glasses, the image of opaque
objects especially, first loses its strong, well-determined
outline—then grows soft and nebulous, and finally melts away in
shadowy confusion. Let the experiment be made of raising the power
of a compound up to that of a 1/60th inch lens—then try it against
the single microscope of that power (having, of course, the utmost
opening the nature of the object viewed will permit). The observer,
if open to conviction, will soon be taught the superior efficacy
of the latter—for it will show the lines on the dust of Menelaus
with such force and vivacity, that they will always be apparent
_without any particular management of the light—nor can their image
be extinguished by causing the illumination to be directed truly
through the axis of the lens (as it always may in the compounds)_.
A due consideration of the teeth and inequalities on the surface
of a human hair, together with the _transverse connecting fibres
between the lines on the scales of the curculio imperialis_, viewed
as opaque objects, will suffice to complete the illustration of
the subject; though the last object is not to be well seen by that
kind of light which is given by silver cups—and a single lens of
1/60th inch focus can of course have no other. The effectiveness and
penetrating faculties of simple magnifiers are invariably increased
by an accession of power however great—that of compounds seems to
be deteriorated beyond certain limits. An opinion may be hazarded
that the achromatics and reflectors yet made _do not really surpass
the efficacy of equivalent single lenses, even of glass, when
their power exceeds that of a_ 1/20th lens, from 1/20th to 1/40th
the vision may be about equal—but from 1/40th upwards infinitely
inferior.
The superior light of the single refraction can need no comment—and
it is evident that there must be a degree of power at which that
of the compounds will become too dim and feeble for vision,—while
that of the single instrument will still retain a due intensity.
For these reasons it is conceived that the close and penetrating
scrutiny of lenses of diamond of perhaps only the 1/200th inch
focus, and an equal aperture (which their very low aberration would
easily admit of,) must enable us to see further into the arcana of
nature than we have yet been empowered to do. Glass globules of
1/200th inch focus and indeed much deeper have been executed; but
the testimony of _lenses_ of diamond would certainly be far more
respectable, and is at least worthy of trial and examination.—C.R.G.
[4] In Dr. Brewster’s treatise on new Philosophical instruments,
Book 5, chap. 2, Page 403—Account of a new compound Microscope for
objects of Natural History—is the following passage: “We cannot
therefore expect any essential improvement in the single microscope,
unless from the discovery of some transparent substance, which like
the diamond combines a high refractive with a low dispersive power.”
From which it seems certain that the Doctor never contemplated the
possibility of working upon the substance of the diamond, though he
must have been aware of its valuable properties.
[5] There are fourteen different crystalline forms of the diamond,
and of this number, from the laws which govern the polarization of
light, the octohedron and truncated cube are probably the only ones
that will give single vision. It is unfortunately very difficult
to procure rough diamonds in this country, so we are compelled to
use stones already cut, and to subject them to trial in the way
mentioned in the text.
[6] As many amateurs of science might take an interest in the
inspection of the peculiar effect these lenses have on transmitted
_light_, I shall be happy to exhibit them, as also the perfect lens.
_Analysis of a newly-discovered Spring, at Stanley, near
Wakefield_.—By Mr. William West.
Mineral springs, dependent for their characteristic properties on
carbonate of soda, appear to have been little noticed by chemists,
and to have been still less attended to as curative means; at least
in proportion to the multitude of cases in which that substance is
administered in various other forms. Indeed the inference to be
drawn from the silence respecting the modes of analysis adapted to
such waters in our best elementary treatises, is that they have
hitherto been very seldom met with. In one district, however, of
Yorkshire, carbonate of soda is of frequent occurrence; it is found
in the ordinary springs; often, at the same time with substances
with which, in artificial solutions, or when concentrated, it, would
be considered wholly incompatible; while at other times it is the
predominant, or the only remarkable saline constituent. An analysis
of a water of this kind, known by the name of the Holbeck Spa, has
lately been published in the Annals of Philosophy, by my friend E.
S. George; similar springs are found, I understand, as far [p022]
westward as Bradford; they are numerous from the borings in and near
Holbeck; while eight miles south, a water similar in its character,
but differing in containing about twice as much alkali in the same
measure, has been discovered at Stanley.
About two miles from Wakefield, near the Aberford or York road, is
an ancient mansion called Hatfield Hall; near the park or inclosure
of which, in boring for coal, the spring in question suddenly gushed
up, when the workmen had got to the depth of eighty yards, and has
continued to run spontaneously, in all seasons, at the rate of six
gallons per minute.
The water at the spring is limpid and very sparkling; the portion
which is allowed to escape, deposits upon the trough and in the
channel through which it runs a quantity of sulphur; the smell is
that of sulphuretted hydrogen; the taste, from the stimulus of the
bubbles of gas modifying the softness of the alkali, rather pleasant
than otherwise.
The appearances presented by re-agents are,—
With tincture of soap, a slight opalescence.
Nitrate of silver, an abundant precipitate, partially re-dissolved by
pure nitric acid.
Sulphate of silver, a precipitate only partially soluble in nitric or
acetic acid.
Muriate of barytes, a slight precipitate.
Lime-water, a precipitate soluble with effervescence in acetic acid.
Oxalate of ammonia, no precipitate.
On boiling, a slight pellicle appeared, soluble in nitric acid.
Carbonate of ammonia, no precipitate, nor any on the subsequent
addition of phosphate of soda.
The water restored the colour of litmus paper slightly reddened.
With tincture of galls and ferrocyanate of potash, no change.
With muriate of lime, the water remained unchanged until heated; but
when boiled, a copious precipitate took place.
When concentrated by boiling, the water reddened turmeric paper, and
effervesced strongly on the addition of an acid.
Nitromuriate of platina produced no precipitate, however concentrated
the water might be. [p023]
The results of the previous experiments indicate the presence of
Soda, Lime in small proportion,
Muriatic acid, No magnesia,
Sulphuric acid, No iron,
Carbonic acid, No potash.
A. To ascertain the proportion of sulphuric acid, sixteen ounces
by measure, previously saturated by acetic acid, were treated with
muriate of barytes; the precipitate, washed and dried, weighed
one grain; this indicates, in the imperial gallon, 3.2 grains of
sulphuric acid, equivalent to 5.8 sulphate of soda, dry, or 13 grains
crystallized.
B. For the muriatic acid; nitrate of silver, added to sixteen ounces
of the water boiled, and the alkali previously saturated, gave a
precipitate weighing 2.8 grains; reduced to the proportion in the
imperial gallon, this amounts to 26.9 grains chloride of silver,
equivalent to 11 grains chloride of sodium (muriate of soda.)
C. The crystalline pellicle separated from a pint of sixteen ounces,
on boiling, weighed 0.2 grains.
This was carbonate of lime; but in the water the lime would be
combined with muriatic acid, forming 0.22; or, in the imperial
gallon, 2.1 dry chloride, or 3.75 crystallized muriate of lime.
D. The precipitate formed on boiling with muriate of lime, weighed
from the pint, 3.6 grains; from the imperial gallon, 34.6 grains;
showing the water to contain in that quantity a carbonated alkali
equivalent to 53 grains of dry, or 59.5 crystallized bi-carbonate of
soda.
E. Muriate of barytes, added to the water left on evaporating sixteen
ounces to two, gave a precipitate weighing 8.2 grains; deducting one
grain for sulphate of barytes, as found in experiment A, we have 7.2
carbonate of barytes; this indicates in the gallon 53 grains of dry,
and 59.5 of crystallized carbonate of soda, as in the last experiment.
Lastly, a pint of sixteen ounces of the water, evaporated to dryness,
furnished in three trials of saline residuum, weighed after short
exposure to a dull red heat, six grains, or 57.6 from [p024] the
imperial gallon. Now we have seen that this would consist of
5.8 Dry sulphate of soda (exp. A).
11. Chloride of sodium ( — B).
1.9 Carbonate of lime ( — C).
----
18.7
38.9
----
57.6
The remainder, 38.9, having been converted by the heat into
proto-carbonate of soda, is equivalent to 54.5 dry, 61 grains
crystallized bi-carbonate, agreeing nearly with the quantities found
from experiments D and E.
Following, as I do, that doctrine which supposes the bases to be
distributed among the acids in a mineral water in the combinations
which possess the greatest solubility, we must suppose the lime to be
in the state of muriate; we shall then have to diminish the muriate,
and increase the carbonate of soda: so that on this view, the saline
constituents of an imperial gallon, in the state in which they exist
in the water, are,—
Soda in combination with carbonic acid, equivalent to
Bi-carbonate or super-carbonate 56 gr. dry. 62.5 crystallized
of soda
Sulphate of soda 5.8 ditto 13 ditto
Muriate of soda (chloride 8.75 ditto 8.75 ditto
of sodium)
Muriate of lime 2.1 ditto 3.75 ditto
The gaseous contents of the water consist of variable proportions
of carbonic acid, sulphuretted hydrogen, and carburetted hydrogen;
the latter gas is continually emitted from the spring, in greater
quantity than the water can absorb; and a portion of the other two
also escapes from its surface. I have made many experiments on
the gas, separated by boiling; but find the results, as I might
anticipate, altogether inconclusive and uncertain. In waters
containing, as at Harrogate, these gases with muriates or sulphates,
boiling may be expected almost wholly to disengage them; but in this
case the affinity of the soda in dilute solution, is likely to retain
the carbonic [p025] acid, and even to cause a decomposition of the
sulphuretted hydrogen, so as to prevent our obtaining, in a gaseous
form, the quantity really existing in the water, and imparting to it
sensible or medicinal properties.
On the subject of medicinal qualities I am at all times cautious of
giving an opinion: but I may observe, first, that as this spring is
dissimilar to any of those which have already attained celebrity, so
none of them can form a substitute for this; it is not Harrogate,
or Cheltenham, or Buxton, or Tunbridge water: the alkaline springs
of the West Riding, of which this is by far the strongest, stand
as medicinal waters hitherto alone; the active ingredient, the
bi-carbonate of soda, being spoken of in chemical works, as “rarely
found in mineral waters.”
Secondly, from the known properties of this substance, carbonate
of soda, and the frequency of its administration in a long train
of arthritic, calculous and dyspeptic complaints, the water must
be highly useful as an anti-acid and as a diuretic; and as the
advantages which native mineral waters possess over artificial
solutions of the substances, in the great degree of dilution, and
the impregnation with gases, and still more in the adjuncts of
leisure, exercise, pure air, regulated diet and early rising, are of
especial consequence in the latter very numerous class of diseases,
those called stomach and nervous complaints; we may fairly suppose
that such a spring will be found to be a valuable addition to those
previously known, applying, as it does, to cases of such frequent
occurrence.
_Observations on the State of Naval Construction in this Country_.
It appears that there is at present a tendency to improvement in
every branch of science; monopoly in intellect may now be said
to be vanishing; and empiricism is obliged to seek dark corners,
to escape the light which is penetrating into regions from which
it had but very lately been excluded. The administration, too,
encourages advance of knowledge; yet notwithstanding these favourable
circumstances, there still exists, in [p026] some minds, an
inaptitude of scientific perception, which induces unwillingness to
acknowledge the advantage that results from the application of the
exact sciences to the useful arts.
This neglect of scientific principles is nowhere more manifest than
in the affairs of naval architecture, and it is not confined to the
Royal Navy, but extends also to our mercantile shipping; and hence
it is that our commercial marine is in some respects behind foreign
nations, especially the Americans, in the formation of its ships:
our merchantmen are, almost without exception, the most unsafe[7]
and slowest ships in the world. The ship-owners, therefore, would do
well to consider this circumstance, and endeavour to devise means of
introducing science into the merchant yards. The establishment of the
new university in the metropolis affords an opportunity of doing it
at a comparatively small expense, by the foundation of Lectures on
the theory of Naval Architecture; and the support even of a separate
institution in the vicinity of the merchant yards of this great port,
for the education of ship surveyors, would soon be repaid by the
improved character of our merchant shipping.
If the science of Naval Architecture depend on certain
physico-mathematical laws, as no doubt it does, it is monstrous to
imagine for a moment that such laws can be developed by a flight of
fancy, or that a man is born with an _intuitive optical_ perception
of the lines of least resistance, &c., or, in the jargon of the
craniologists, that he has a naval-architectural bump on his skull;
yet one would think that such was the case, when we see men, we
cannot say philosophers, start up and loudly assert that they are
in possession of the secret of construction; and they are believed
because their hypotheses are never submitted to the examination of
those who are capable of detecting their fallacy.
The Experimental Squadrons have, with a multitude of perplexing
results, elicited, it must be confessed, at least an interesting
fact, viz. that there has been an establishment seventeen years in
this country, in Portsmouth dockyard, for the scientific education
of naval architects, for the Royal [p027] Navy.[8] From the plan of
education, as laid down by the Commissioners of Naval Revision in
1810, it appears that, to a requisite knowledge of the _practice_
of their profession, the gentlemen composing this body of naval
constructors unite a sound and competent one of its _theory_[9].
It can only be from such a source that we can look for the
improvement of our men of war, and it is to be regretted that every
means should not be taken to avail ourselves of it: but unhappily
such is the force of prejudice that, unless some alteration should be
adopted in this institution, it will be in vain to expect advantage
from it.
The objection urged against this establishment, namely, that the
scientific education it gives to its members precludes them from the
attainment of a due knowledge of the practical construction of our
ships, is so absurd, that none but weak or jealous minds could ever
have brought it forward. Shall it be laid down, in the present age,
as an axiom, that a profound ignorance of the principles of his art
is the one thing essential to the formation of what is generally
meant by the term “practical man?” We contend that, having made,
_in vain_,[10] a long and most indulgent trial of a system without
science, if we may use such an expression, we must extend to one
in alliance with it, a like patronage, before we can be allowed to
pronounce a fair and legitimate judgment upon its efficiency.
But even in the peculiar path in which the naval architects educated
at Portsmouth might be supposed to excel, we do not find that any
opportunity is allowed them to come forward, nor shall we see this
until some effort is made by the heads of our naval departments, to
allow a broad and open competition to take place. It may be urged,
that the learned Professor at Portsmouth (Dr. Inman) in himself
includes all that can have [p028] possibly been taught or understood
in the establishment over which he presides, and that therefore he
is the representative of it in the late and present trials for the
palm of excellence; but we cannot by any means assent to this: many
of the students must have left his tuition seven, eight, and nine
years, and must be between thirty and forty years of age; and it
would be strange indeed, if during such a period, and in the prime
of life and intellect, some of these, if not all, had not cultivated
the science after their own bent of mind, and formed original ideas
on the subject: we say, therefore, that Dr. Inman’s constructions
cannot be called the production of the establishment—they are merely
the effort of one man, whose attention it appears is distracted by a
multiplicity of occupations, and can only, along with the vessels of
Capts. Symonds, Hayes, and Sir R. Seppings, be deemed criterions of
the particular views of an individual.
Mysticism and ignorance always accompany each other; and we may
reckon that in proportion as the latter disappears from amongst our
ship-builders, so will the absurd vagaries of the former recede, and
the subject be placed at last on the true principles of philosophical
induction, instead of the caprices of imagination. We look forward,
therefore, to this new body of naval architects for the expulsion of
all quackery from their profession, and for the exposition not only
of what we really do know, but also of what we do not know about it:
this is the only way to arrive at truth, which should be the sole
object of all investigation; but which we are afraid has hitherto
been sadly garbled and perverted wherever it has had to do with naval
architecture in this country.
But we repeat that we do not see that the nation is at all likely to
benefit from the science or exertions of those gentlemen so long as
they are placed in situations where a superior education can have no
other effect than producing disgust and chagrin in the mind of the
possessor; and if the institution at Portsmouth be designed for no
better purpose than that of supplying house-carpenters, joiners, and
still more inferior trades, with foremen, it had better be abolished.
Some would regard it, as at present used, as a gross mockery on the
public [p029] at whose expense it is supported; it is certainly a
cruel one of those who have been induced, by the fair and brilliant
prospects held out to them of support and encouragement, to devote
their lives to this branch of the public service.
But to return to the Experimental Squadron: it is with regret that
we must conclude, upon a careful consideration, that, although the
experiments are carried on with so much vigour and interest, they are
evidently founded on imaginative views, and that there cannot exist
any thing like legitimate data where so many failures and anomalous
results obtain. Who can read the account of the first Experimental
Squadron[11], without immediately perceiving that the constructors
of the contending vessels, however sanguine each might have been of
the success of his particular fancy, met with nothing but the most
perplexing results? We see sometimes one and sometimes the other
vessel claim the palm of excellence, and finally leaving the subject
as much in the dark as ever. This is the natural consequence of the
non-application of inductive philosophy to the question before us,
and the most important conclusion that can be gathered from the
experiment is, that we have begun at the wrong end, and that it is
high time to employ analysis instead of synthesis to effect the
desired objects: for in the present state of the theory of naval
construction in this country, there are yet no data existing to
effect with precision and confidence the synthetical composition of a
ship.
We cannot refrain here from noticing the paucity of information
contained in the reports hitherto made on the first Experimental
Squadron. The best one[11] is but little removed from a ship’s
log book, and in some respects is inferior to it: it is of such
a scanty nature, that we can scarcely inform ourselves on any
point, and that only in a _relative_ degree, of the qualities of
the vessels composing it: we cannot find out any mention of their
_absolute_ velocities on the different points of sailing, which is
a most important omission. We are neither informed in what way the
observations were conducted, whether they were made simultaneously
or not: unless the former, any attempt at comparison must be very
doubtful, if not entirely fallacious. Circumstances of wind and
the weather may very widely alter in the [p030] course of a short
time, and every endeavour at legitimate analogy be destroyed by such
variation. We strongly suspect that this is one cause of perplexity;
and another prolific one is the vague idea given of the strength of
winds by nautical language. Nothing but the determinations of the
anemometer should ever be allowed to appear in an account of such
experiments. Every circumstance attendant on the quantity and trim of
sail, the heeling, the rolling and pitching of the ship, position of
the rudder, &c. should be accurately ascertained and _tabulated_; for
it is next to an impossibility and a wilful waste of time to attempt
to institute comparisons without pursuing a system of tabulated
results, which should be kept in the same form on board each ship.
We must also express our regret that the scientific professor at
Portsmouth does not appear to have ascertained the position of the
centre of gravity of any of his ships, with regard to height, by the
simple and easy experiment long known in principle, and described
lately with geometrical rigidity in two or three publications by
some of his pupils[12]. The knowledge of the position of this point
would have placed him so far above his competitors, in so many
important particulars, that we are surprised he should have thrown
away his advantage, and descended to a level with his less scientific
opponents. We are afraid that, here again, imaginative views have
stepped in, and taken the sober mathematician from the only path by
which excellence can be attained. We are at a loss to conceive how
the stabilities of his ships can be said to be ascertained without
the knowledge of the position of this point.
Some of the obscurity which pervades this difficult subject may be
overcome, as to broad and general principles, by attentively and
_coolly_ observing the progress of marine architecture, since the
introduction of cannon into naval warfare, and more particularly
during the last century and a half. We shall then clearly perceive
that the French, who, as early as the beginning of the reign of Louis
XIV., employed men of first-rate talent in their naval arsenals,
and neglected no opportunity for the [p031] advancement of science
in them, increased and kept increasing the dimensions of their
ships, more especially the length, the ratio of which to the breadth
has been augmented by them from about 3-1/4.1, to 4.1 within the
last century. While this principle was acted on, the improvement
of their ships was gradual; and by referring to our own progress
in the art, in tardy imitation of the practice of the French, we
shall likewise conclude that our navy has derived precisely similar
advantages from the same causes. Here we have at once two grand but
_concurring_ results derived from an experiment, not made on one or
half a dozen different vessels, but on the whole navies of the two
most powerful maritime states in the world: and if to these we choose
to add the result of the practice of the same means on the Spanish
and other navies, we might surely be warranted in saying, from this
broad but _certain analysis_ of _facts_, that, in relation to the
hull, the _general increase of dimensions, with a greater relative
length_, is one cause of the improvements that have been made in the
sea-going qualities of the ships composing the fleets of the present
maritime powers: the question therefore that remains to be decided
on in relation to this principle is, whether we have arrived at its
utmost practicable limits, or rather, whether we have arrived at the
_maximum_ of improvement it is capable of producing.
This brings us again to the experimental squadrons, as far as they
are connected with, and illustrative of, our observations; and the
first question naturally put forward about them is, whether there be
any thing very peculiar in the formation or dimensions of the rival
vessels? We suspect that the answer cannot otherwise than disclose,
that neither in principle, dimensions, nor in the formation, can they
be said to differ very materially from each other, or from ships of
the common construction: indeed we perceive in some a retrogression
of ideas and a violation of the principle, that the increase of the
ratio of the length to the breadth, in conjunction with a general
increase of dimensions, has been a predominant cause of improvement.
The fact also of so immaterial a difference necessarily includes a
system of masting and sails equally confined, and totally inadequate
to produce any great superiority of sailing over ships to which they
are so nearly equal in principal dimensions. [p032]
After so many years of trial with the present nearly invariable set
of principal dimensions, during which period it may be said, that
every possible contour of hull has been experimented on with them,
we are inclined to think that almost all has been done that could
be done under such restrictions, and that some great step must be
made in one or other of the principal dimensions themselves, with
correspondent alterations in the masting, before we can expect to
see a decided and great improvement in the sailing of our ships.
The depth is an element which has arrived at its limit from very
apparent external causes; but the length and breadth remain to the
skilful constructor without any such clogs to his endeavours; and
he has only to accommodate their relation to each other in the
manner most conducive to velocity, which in our opinion is the very
capital object of naval construction, both in ships of war and of
commerce. That it is so in the former, no one will, we apprehend, on
due reflection deny; but there will be many who will assert that it
cannot be obtained, in the latter, without a sacrifice of capacity;
which will defeat the object of carrying large cargoes: to this
we may reply, that if a vessel with an expense of one quarter the
capacity can make _three_ voyages instead of _two_, will not the
merchant be still a considerable gainer in capacity, and still more
so by a ready return of his capital[13]?
All observations on well-conducted experiments concur in proving that
velocity is gained by increasing the length, to a much greater degree
in relation to the breadth, than has ever yet been done in ships; and
that the increase of the same element contributes to their weathering
powers is too obvious to need insisting upon: it is also generally
advantageous, when not carried to an extent which would seriously
retard the manœuvring of the ship. This limit has not yet by any
means been determined; for it must be recollected, that although
the additional length increases the resistance to rotation about a
vertical axis, yet the power of the sails to give rotation about the
same is also increased, although not in so high a ratio. The power of
the rudder to produce rotation is also greater in a long ship than
in [p033] a short one, not only on account of the greater distance
it is from the axis of rotation, but also on account of the greater
velocity, and the more direct impulse of the water on it.
The increase of the ratio of the length to the breadth to produce
velocity should not interfere with the increase of breadth necessary
to produce stability or capacity; for both these qualities, varying
as higher powers of the breadth, a very small increase of breadth may
be attended with a considerable increase of length. If we compare
the Caledonia’s (120 guns) dimensions with those of the Royal George
and Queen Charlotte[14], of 1788 and 1789, we shall find, that 13
or 14 times as much length as breadth has been added to the first
rates of our navy. If we refer to the dimensions of the Commerce
de Marseilles, and those of the next preceding three-decker of the
French navy (for instance, the Ville de Paris[15], taken in Lord
Rodney’s action), we shall find that the French naval architects gave
in her 21 times as much increase to the length as to the breadth. If
this could be done with safety in a three-decked ship, with such a
vast top weight, much more could it be carried advantageously into
effect in ships of two decks, and frigates; but we do not find, in
the latter classes of the ships of the French navy, the increase of
length to go beyond six times that of the breadth. If we refer to the
Old Bellerophon, built in 1772, and the New Bellerophon, built in
1819, we shall find an increase of 24 feet in length, to 1.58 feet
increase of breadth; or the former more than 15 times the latter[16].
To those who oppose the objection that a greater length than at
present used would make the manœuvring of a ship too slow, we answer,
that as the Caledonia and the present first rates of our navy,
although from 10 to 15 feet longer than our two-deckers, are found to
be capital ships in this respect, there is a sure ground to believe,
that the addition of 20 feet in length to the present two-deckers
would not render their celerity [p034] of evolution less than that of
the three-decker; and since, from the reduction of weight aloft, the
centre of gravity would be lowered, and the displacement required to
be less, a somewhat smaller breadth might be allowed to a two-decked
ship of 206 feet long, than to one of 196 feet (especially since
the quantity of sail, remaining the same, is lowered by one whole
depth between deck), a smaller midship section would be, _cæteris
paribus_, required; the velocity of this ship might be considerably
increased. Nothing however can be precisely determined on, with such
a complication of circumstances, beyond a general idea. Calculation
and a strict analysis of ships must be resorted to, in order to fill
up the outline of our reasoning.
But for the same reason that we imagine that an addition of 20 or
perhaps 40 feet would not sensibly injure the celerity of manœuvring
of our two-deckers, we should think that the same increase of this
dimension might be tried without much risk to our first rates, with
an increase of breadth not exceeding 1/20th part that is given to the
length.
We repeat that the very capital object of the science of Naval
Construction is _velocity_, and we are decidedly of opinion that
it is attainable in a much higher degree than at present, without
compromising other necessary qualities, for which we have the
concurrence of facts as far as they go.
The Anglo-Americans, in the last war, took every possible advantage
suggested by views similar to those we have been adverting to, in
the construction of their large frigates. They had, it may be said,
to create a martial navy, and they had to oppose it against fearful
odds; but, free from the prejudices and errors so blindly cherished
by their opponents, and which constantly oppose reform by always
declaring the present practice to be the best, they did not retread
the old path, but began at its last step, and boldly advanced on
this principle into all the branches of the art. They built vessels
upon the most enlarged dimensions, and of a superior weight of
metal, and gave an increased ratio of length to the breadth. The
result of such a procedure, justified the confidence of the American
naval architects in only _one_ maxim, founded upon the _scientific_
observation of facts, and may give us a faint idea of what might
be effected by a still more enlarged and mathematical analysis.
[p035] Our frigates were so inferior to theirs in every way, that
they brought nothing but disasters upon us, excepting in the action
between the Shannon and Chesapeake, and one or two others, where,
assured by their previous successes, our gallant opponents threw away
the advantages possessed by their ships, by coming to close quarters
at once, and deciding the contest hand to hand.—Our ships of the line
could never bring these frigates to action, and owing alone to their
extraordinary sailing, did they evade and mock a large British fleet.
We were finally obliged to build 60-gun frigates after their method,
but when it was _too late_ for the exigency of the period; and thus
it has ever been our fate, for want of science in the constructors of
our navy, to follow the steps of our enemies at a humble distance,
and to be only then driven out of the old track by a terrible
experience of its inefficiency.
Nor have the Americans stopped here;—Mr. Huskisson plainly tells us
that “America is, year after year, augmenting its military marine, by
building ships of war of the largest class[17].” According to Capt.
Brenton, they have built a first-rate[18] of 245 feet length on the
gun deck, and 56 feet broad[19], to carry 42-pounders on the lower
deck, and 32-pounders on the other decks.
Our small class of 74-gun ships lately converted into frigates
carrying _fifty_ 32-pounder guns, we are fearful can only produce
disappointment if ever brought against the American frigates (not by
conversion, but by _construction_), which carry _sixty-two_ guns of
the same calibre, and are 180 feet long on the gun deck.
We must not forget also that our active neighbours the French have
now adopted a most formidable description of [p036] frigates, with
curvilinear sterns[20], and many other important improvements. They
mount 60 guns and carronades—viz. 24-pounders on the gun deck, and
36-pounder carronades on the flush deck.—The former calibre is
equivalent very nearly to 26, and the latter to 39 lbs. avoirdupois.
When we reflect on these circumstances, we cannot but feel surprised
that so many frigates of inferior force and dimensions should be
building in our dockyards. In time of emergency they will only bring
on us a repetition of former disasters and deficiency. We contend
that, instead of building ships of only _equal_ force to those of our
rivals, and thus _waiting_ for the developement of _their_ designs
before we can venture on a single step, we should build beyond them
in every respect. It must and ought to be recollected, that peace in
these matters produces a contest of intellect, and those will have
the advantage in it who attack instead of standing on the defensive.
We ought to lead the way, and to be at the head of the maritime
world, not in _number_ alone, but also in the _individual force and
qualities_ of our ships.
Having expatiated on the advantages of an increased ratio of length
to breadth in relation to the hull of a ship, we will just glance
at some of the principal effects it would have upon the masting
and sails; and here again we conceive that Professor Inman has, in
common with many others, relinquished the many good effects resulting
from it, for the inadequate one, of being able to carry a somewhat
greater quantity of sail, which must necessarily be lofty, and which,
(setting aside this detracting circumstance,) as the velocity of a
ship varies only as a _fractional_ power of the surface of canvas
spread, cannot produce the degree of fast sailing to be wished for,
but at an immense and impracticable quantity of sail[21].
A greater proof of the inadequacy of the present system of [p037]
lofty sail cannot be cited than the fact of its not procuring, under
the most favourable circumstances, a rate of sailing rarely exceeding
one-fourth the velocity of the wind.
As the number of masts should be so regulated as to create facility
in managing the canvas, which is well known to be at present hardly
manageable in a gale of wind, on board large ships, from the enormous
size of each individual course and topsail, we should not hesitate,
therefore, to have _four_ vertical masts, as recommended by Bouguer,
instead of three, in ships built in accordance with the principles
we have been discussing. This would, _cæteris paribus_, require
shorter masting and smaller yards, and the sails being much less,
individually, would be more easily managed and not so liable to
accidents.
From what has been said, and the actual experiments now pending, it
is apparent that the theoretic construction of ships is at a very
low ebb in this country; yet a fine opportunity now presents itself,
if we choose to avail ourselves of it, for rescuing the nation from
this generally acknowledged odium. Let a proper use be made of the
corps of Naval Architects we have, somehow or other, at last got, and
let their exertions, under a degree of encouragement equal to that
bestowed on the old ship-builders _in vain_ for so long a period, be
directed towards the improvement of their art. If they fail, they
cannot claim the excuse of having their endeavours repressed; if they
succeed, as no doubt they will, in advancing their profession to
something beyond mere carpentry, we shall be enabled to bid adieu to
the old and _ruinous_ method of blundering, under the reign of which
nothing but disappointment can ever be reasonably expected.
We have seen and do still see the immense advantages derived by our
country from the encouragement of those branches of science connected
with its manufactures and agriculture; and if we wish to keep our
present superiority, we must follow up vigorously this principle in
all its universality. To the cavils of ignorance and bigotry against
such a mode of proceeding we would answer, in the words of one of
the most enlightened members of the present administration, “This
country cannot stand still, whilst others are advancing in science,
in [p038] industry, in every thing which contributes to increase the
power of empires, and to multiply the means of comfort and enjoyment
to civilized man.”[22]
It is to be hoped, therefore, that His Royal Highness the Lord High
Admiral will extend to this most important national institution, the
School of Naval Architecture, the same vigilant and scrutinizing
eye that every other branch of our naval system is at this moment
experiencing from him, and that he will extend to it that fair play
and encouragement which has hitherto been denied to it. As a seaman,
he can fully appreciate and understand how much the bad qualities of
a ship may neutralize the best exertions of the most experienced and
skilful sailor; and, on the contrary, what a degree of confidence
may be insured in naval operations with excellent ships. We feel
persuaded, therefore, that he will not allow others to think for him
in a matter of so much national importance, and thus allow private
ends to interpose to the disadvantage of public views; but that he
will investigate and judge for himself. We would humbly suggest to
His Royal Highness to inquire into the individual acquirements and
productions, both of a _theoretical_ and _practical_ nature, of those
who have been educated in this establishment, and he would soon be
able to decide whether they be fitting or not for the important task
of constructing our ships, and for the confidence and protection
which we think we have shown has hitherto been ill-advisedly withheld
from them. Such a line of conduct would very soon carry our naval
architecture to a pitch of excellence _worthy_ of imitation, and
instead of being indebted to foreigners for models, we should be
able, with just pride, to point to the productions of British science
and intellect in this noble art.
FOOTNOTES:
[7] By referring to Lloyd’s List, it will appear, upon a moderate
average, that _three_ English merchant vessels are lost every _two_
days!
[8] See No. II. of the Naval and Military Magazine, published in
June last.
[9] This will be readily acknowledged by those who will choose
to read the “Papers on Naval Architecture,” and the “Essays and
Gleanings on Naval Architecture,” two periodical works proceeding
from the members of this institution.
[10] See the Third Report of the Commissioners of Naval Revision,
and the Resolutions of the Society for the Improvement of Naval
Architecture, in which the old system of providing ship-builders for
the Royal Navy is condemned in the most unqualified terms.
[11] Vide No. 1 of the Papers on Naval Architecture.
[12] Vide Annals of Philosophy, for November, 1826; No. 1 of the
Papers on Naval Architecture, and No. 11 of the Essays and Gleanings
on Naval Architecture.
[13] Foreign nations, and more particularly the Americans, find
their advantage in having swift merchant ships, and therefore our
assertion is warranted by facts.
[14] Caledonia, length 205 feet, breadth 53.5; Royal George, length
187 feet, breadth 52.33 feet; Queen Charlotte, length 190 feet,
breadth 52.33 feet.
[15] Ville de Paris, length 185.62 feet; breadth 52.7 feet; Commerce
de Marseilles, length 208.33 feet, breadth 54.79 feet.
[16] Old Bellerophon, length 168 feet, breadth 47.33 feet; New
Bellerophon, length 192 feet, breadth 49 feet.
[17] Vide this gentleman’s speech on the Shipping Interests in the
House of Commons, May 1827.
[18] Called by Capt. Brenton the Ohio; but it appears from Lieut.
De Roos’ personal narrative, just published, that the Ohio is a
two-decker of 102 guns. It is to be supposed, therefore, that the
three-decker of 135 guns, called the Pennsylvania by the latter, is
the ship alluded to by the former. It is a matter of great regret
that Lieut. de Roos has not presented us with the precise dimensions
of these ships.
[19] These dimensions carry the ratio of the length to breadth above
4-1/3 to 1.
[20] The French Admiral Willaumez, in his “Dictionnaire de Marine,”
published in 1820, says under the article _Frégate_, that as far
back as 1804, he had proposed a plan for a frigate of the largest
size, with a round stern, wherein the quarter galleries were
suppressed: the first frigate upon his plan was built at Brest about
1821.
[21] As the square root, so that to get _twice_ the velocity, _four_
times as much canvas must be spread; and this is the most favourable
estimate that can be made.
[22] Vide Mr. Huskisson’s speech on the Shipping Interests.
[p039]
_On Malaria_. No. II.
[Communicated by J. Mac Culloch, M. D., F. R. S., &c. &c.]
Having pointed out, in the former paper on this subject, the nature
of the soils or places, of whatever description, by which malaria is
generated, it remains to notice a few other circumstances connected
with its natural history, a knowledge of which is essential for
the purposes of prevention; and finally to describe such modes of
prevention, applicable to these several circumstances, as have
been found useful in guarding against the attack of diseases from
this cause. Under the first head, there remain to be considered,
the effects of climate and season; the changes which occur in the
production and propagation of malaria, from various natural and
artificial causes; and also, the various modes in which it is
propagated.
It has already been remarked, that a certain elevation of temperature
was necessary to the production of this poison, though what the
precise degree is, has not been ascertained; and as this is, chiefly,
what distinguishes the regions or periods of the year which generate
malaria, I need not make two divisions of season and climate. If,
however, this temperature is not fixed, it will perhaps suffice
for our present purposes to say that the greater part of Scotland,
whether as to climate or season, seems incapable of generating the
disease from this cause; though there are exceptions of a permanent
nature, or exceptions of climate, as was perennially true of the
Carse of Gowrie before its drainage; while there are others which
happen when, as in the last year, there has been a peculiarly hot
summer, and which are exceptions of season.
And thus it is as to more northern regions; where a hot summer
becomes more than an equivalent for an average low temperature;
as an example of which, there is no place where intermittents are
more severe and abundant than at Stockholm. But the extreme of evil
from this cause occurs, as is well known, in the tropical climates;
appearing almost proportioned to the heat of the climate, and what is
important to observe to the moisture also. The destructive effects of
certain parts of Africa, India, America, and so forth, are familiarly
known; and [p040] it is in these countries especially, that the
diseases from this source constitute nearly the entire mortality of
the human race. And thus, for Europe, it is in Spain, Italy, and
Greece, and chiefly on their Mediterranean shores, that the activity
of malaria scarcely yields to that of the intertropical climates;
while in France, Holland, Germany, Hungary, and with us, in a far
less degree, the production will be found regulated by the heat of
the summers, all other circumstances being the same.
And if we thus account for the variations in the quantity and
virulence of diseases in any given country, for noted seasons of
epidemic in the countries which I have just named, and for the great
prevalence of fevers among ourselves during the last few years, and
particularly in the last summer, there is another point of scarcely
inferior importance to be taken into the consideration, independently
of that which relates to peculiar winds as connected with the
propagation of this poison;—and this is, moisture.
I need not repeat that water in some form is necessary to the
production of that peculiar vegetable decomposition which is the
source of this poison; and so true is this, that even in the
tropical regions, the diseases from this cause are nearly unknown in
districts of peculiar dryness, as they are in the drier seasons of
those countries. Thus, for example, Egypt is free from such fevers,
except at the period of the subsidence of the Nile, unless where,
as at Damietta, the cultivation of rice is pursued; and the same is
true of Mesopotamia very remarkably: and if I dare not extend these
illustrations, I must remark that in all these cases, the action of
moisture is twofold, inasmuch as it not only accelerates vegetable
decomposition, but renders the atmosphere a fitter conductor of this
poison.
Taking these two causes of the increase in the quantity and in the
action of malaria, we can explain many particulars which relate
to its power in producing diseases: and as the knowledge of these
is important as far as relates to the main object of this paper,
prevention, it becomes necessary to explain them at a little more
length.
As to season, the simplest case is that of the intertropical
climates; and Africa offers the plainest instance among the [p041]
whole. There, the malaria and the fever commence at the moment the
rain falls; diminishing as the ground becomes thoroughly wetted,
and recommencing as it dries. The explanation of all this ought to
be obvious; and the same analogy governs all the hotter climates,
as, though less conspicuously, it does our own. Hence we explain,
both as to our spring and our autumn, the effects of heat following
rain, or the reverse, and the diseases which are consequent on those
changes: and thus it is, though more remarkably, in Italy, that a
rainy autumn increases the number and severity of fevers; or, if the
summer has been unusually dry, that they often do not appear till the
commencement of the autumnal, or even the winter rains. And hence,
also, even with us, the occurrence of a single rainy day or week, in
the midst of the heats, will produce fevers; while the effect of this
influence is such, that should there even be an entire rainy summer,
and the subsequent one be hot and dry, this will be attended by an
unusual production of malaria and disease.
And if I cannot detail all the various modes in which these
circumstances may be modified, and how their effects may vary, it
will be useful to make one remark on an error as relating to it which
is universal among us, and into which even Lind has fallen. The error
is, to think that the rain, the moisture, or the cold is itself the
cause of the diseases which follow this state of things; while it is
obviously a case analogous to that of Africa, if less severe, and the
malaria is produced by these circumstances on soils which I formerly
pointed out, and which Lind, like every one else, had neglected. But
if I must pass over many interesting and useful conclusions to be
drawn from these general principles, there is one fact which I must
notice, and it is this:—
In spring, the combination of heat and moisture, easily explained,
generates, most commonly, intermittents; or the effect of the malaria
at this season differs from what it does in autumn: while as the
heat advances and the ground dries, this kind of fever ceases to be
produced, a new species, or the summer remittent, taking its place
when the heat and the moisture of autumn begin to act. But under
peculiar seasons of heat and moisture with us, it sometimes occurs,
as it has done [p042] within the last years, that the intermittent
season runs into the remittent one, or there is no midsummer interval
of freedom from disease; while it has also happened, and in some
parts of England in this last year, that what would have been
intermittent fever in other years has been remittent; or the common
fever has occupied the whole summer, continuously, even from March to
November, as is the case in the worst regions of southern Europe.
Now, under these exceptions, which I was bound to explain, the
commencement of intermittent, or of vernal ague, may be fixed about
the middle or end of March, and its termination similarly in May;
while that of remittent may be placed in the beginning of August,
and its termination with the middle or end of October. How these
periods may otherwise be affected by the more or less insalubrious
nature of the district or place, will easily be judged of by those
who will reflect for themselves on what I dare not explain, lest I
should infringe too far on my limits. All else that I can venture
on, as to this part of the question in hand, relates to the effects
of the different times of the day on the production, propagation, or
influence of malaria, and it is one which is of no small importance
in a practical view.
Whether the changes as to temperature and moisture which occur within
the space of twenty-four hours, affect the production or propagation
of malaria, I will not here inquire minutely, from the fear of
prolonging this very limited paper; but the general facts, as to its
effects, are these: If we commence with the sun on the meridian,
there appears, even in the worst climates, very little hazard of
fever; while in Italy, it is believed that there is, generally,
little or no hazard, except in some peculiarly pestilential places,
and under particular kinds of inattention or neglect. Either the
malaria is decomposed or destroyed by the heat, or else the air from
its dryness ceases to be a conductor; but as evening approaches,
its influence becomes powerful and dangerous, being supposed most
generally to extend all through the night; while in some parts
of that country it is a popular belief that it terminates before
midnight, or with the precipitation of the atmospheric moisture.
Whether this last opinion is true or not, the general fact explains
the popular [p043] belief, and truth, respecting the poisonous
effects of dew in the hot climates; the supposed pernicious quality
of this depending evidently on the malaria by which its formation is
accompanied. And in this case it is probable that the evil arises,
not from a fresh or peculiar generation of malaria, but from the mere
fact that the moist atmosphere is a better conductor than a dry one.
Not to be unnecessarily minute, we thus also explain the danger of
exposure to the morning air in similar situations; the facts, as
they relate to the conducting of malaria, being the same, though the
meteorological circumstances are somewhat different. Hence, also, we
see why the grey mists which hang over wet grounds in the evening
in our own climate, are esteemed pernicious; the truth, however,
being, that they are perfectly innocent at certain seasons and in
certain places—as in the greater part of Scotland, for example, or in
those places and at those periods where malaria is not produced. The
distinction is valuable, because of the inconvenience of restrictions
on this subject, and because to know where the hazard really lies
is to reduce those, and also to prevent the infraction of rules by
not extending them beyond what is necessary; and thus also by seeing
what are the real dangers of what is called night air, we more easily
avoid them. Night air is avoided now, under a false philosophy,
because it is cold or damp, or for some other vague reason; while
the dangers from mere dampness or cold are as nothing compared to
those here pointed out; which also occur precisely where they are
least feared, namely, in warm summer evenings, after refreshing
showers, and so forth. Hence it is that fevers are produced in
summer, in rural situations, and especially perhaps amid the most
engaging scenery, by evening walks and exposure to what is naturally
considered, as it is felt to be, a balmy and refreshing sequel to
a hot day. Let this be enjoyed where it can with safety, and as it
often may; but such evening walks will not be safe in any of those
situations which I need not repeat here; after having detailed them
as I have done in the former paper. And lest I should be accused of
wishing to excite unnecessary alarm, I consider, on the contrary,
that it ought to be diminished by these remarks; because, if we
take the whole of [p044] England, there is perhaps not one acre in
a hundred thousand where there is danger from night air, or from
malaria in any mode; so that to distinguish where that lies, is to
have relieved from useless fears all those who may learn to make the
distinctions under review.
To pass from what relates to climate and season, and to proceed to
the propagation, simply, of malaria, it is almost superfluous to
say, that its influence, as to the production of disease, is much
regulated by proximity, which implies a state of concentration or
accumulation. Hence the danger arising from vicinity; while, as I
formerly remarked, where the generating source is small, this becomes
necessary to its effect, since dilution may be expected to destroy
the power of the poison.
For analogous reasons, its effect in the production of disease is
increased by concentration or condensation; and such a state of
things takes place in narrow and confined valleys, or in places
surrounded by woods, or in woods themselves; in any situation, in
short, where the poison is produced, and is so sheltered from winds
that ventilation becomes difficult. And if it is probable that this
is one chief reason of the peculiarly insalubrious nature of woods
and jungles in hot climates, so is it an universal remark in Italy,
that the short valleys in which the air cannot circulate are among
the most pestilential spots. And if this explains, also, in some
measure, the bad effects of calm weather, so does it account for the
unusually pestiferous nature of rivers and lakes confined within
wood, as are those of the tropical climates, and as there are many
also in different parts of Europe. That we ourselves are not exempt
from these additional causes of the influence of malaria, would be
easily shown by many references, were it not for the reason which has
caused me to exclude them.
It is another important question for practice, how far and in what
manner malaria can be conveyed by the winds to places where it is not
produced, so as to act in exciting disease. That it is conveyed to
certain distances by winds is amply proved by an abundant experience,
and I may first detail a few of the most useful particulars as to
this fact. In Italy and Greece, it is observed, that where long
valleys terminate on sea shores, on which the exits of the rivers are
swampy, it is an [p045] effect of the sea breeze, by crossing such
marshy ground, to convey the malaria up into the interior country,
to considerable distances, and to places which are in themselves
not insalubrious. Thus, also, does such a breeze, especially when
it is a warm wind, convey the poison up the acclivities of hills,
even to a considerable range of distance or elevation; a process
facilitated by the natural tendency of such winds to ascend. And as
a striking proof of this migration of malaria, it appears from Capt.
Smyth’s statistical account of the insalubrious villages in Sicily,
that out of more than seventy, about one-half are not seated near or
on lands producing this substance, but on acclivities, at varying
distances—thus receiving it through migration. The same is remarked
by Montfalcon of many towns in France; while in some, the place at
a distance is even more unhealthy than that which is immediately
situated in the marsh itself: and in our own country, this is equally
said to be true of the backwater at Weymouth, and of the marshes of
St. Blasey in Cornwall, acting more powerfully at some distance than
in the immediate spot.
With respect to the absolute distance to which the malaria can be
conveyed, it is yet an obscure circumstance, or at least the maximum
has not been fixed; but it is at least ascertained that the convent
of Camaldoli receives it from the Lake Agnano, at a distance of three
miles; while from certain naval reports, a distance of five miles has
been proved to permit its transmission,—and from an evidence that
cannot be doubted, inasmuch as it was the sudden breaking out of
fever in a healthy ship, anchored at that distance from the shore,
on the coming off of the land wind, attended by its peculiar and
well-known smell.
These facts are satisfactory thus far, and it would be abundantly
easy to add to them; but there is reason to suspect that it can
be conveyed to far greater distances, in certain favourable
circumstances: those reasons, in the first place, being derived from
certain meteorological analogies and considerations, and in the next
confirmed by experience. It is notorious that the ague appears on
our eastern coasts with the first east winds of spring; and while
this circumstance is most common on those of England, as for example,
in Kent, Essex, Norfolk, [p046] Suffolk, and Lincolnshire, it is
not thus limited, since it is known to happen further north, and
even in Scotland, where malaria is not indigenous to the soil. It
is very true that if we take any inland position in the places thus
noted, the natural solution is, that the malaria is generated in the
very soil itself of England, and merely propagated, perhaps even to
very moderate distances, through those winds. But the occurrence of
disease cannot be explained thus, when the place in question is so
situated that there is no land to the eastward, or when the breeze
is, most literally and rigidly, a sea breeze; while, when ague thus
occurs on the east coast of Scotland, where it is not produced by the
soil, it must be imported by the east wind.
These are the facts; while as malaria is not produced by the sea
itself in any known circumstance, though a vegetating sea beach
may give rise to it, we must seek the cause in lands far distant,
and consider this as a case of propagation of the poison from the
shores of Holland; and those shores are unquestionably competent to
that effect: so that the only question that remains, the fact being
admitted, is, whether, _à priori_, or theoretically, such a view is
probable, or whether it is consistent with those physical principles
that are concerned in the propagation of malaria.
I am aware that such a view will excite the incredulity of those
who have not attended to this subject; though it appears to me that
it comprises nothing averse to our knowledge of the philosophical
circumstances concerned. In the first place, let us remark that the
east wind, and particularly the east winds of spring, are notorious
for their moisture, and that a moist air is the best conductor of
malaria, as moisture in the air, under the form of evening mists, or
in other modes, appears even to be its proper vehicle, or residence,
if I may use such a term; and though I have not as yet separated
the case of a fog, I may now remark, that the effect in question,
or the production of agues by fogs arriving from the sea, is even
more notorious than their generation by an ordinary clear wind. So
notorious and popular, indeed, is this fact, that the fog itself is
deemed the source of the disease, as the east wind under any form is,
in other circumstances; while I hope it will even now appear, [p047]
that the real cause lies in the malaria transported or conveyed
by those winds or fogs, and of which they are the true and best
repository and vehicle.
And these are the reasons for thinking that the malaria, with the
wind, may be transported to a distance as great as that which the
present view requires; most easily perhaps in a fog, but without
difficulty even in a clear wind. It is remarkable that the east wind,
as it is the most persevering, is that one also which preserves the
most steady horizontal and linear course. I have also shown, in a
former work, that it is a property of winds to travel in distinct
lines through a tranquil atmosphere, and often in streams of a very
limited breadth; that opposing streams will also move, in absolute
contact; and that even rapid streams of wind will cross each other’s
courses without difficulty. This proves that, in any such stream,
there is a principle of self-preservation or integrity, and renders
it probable that the several portions retain the same relative places
to each other, at any distance, during the career of the whole; and
there is a proof of this afforded in the fact of those columns or
streams of insects which are brought over by such winds, and very
frequently from those very countries, or from Holland and Flanders,
in the most regular order, or without disturbance or dispersion.
Hence it may be argued, that if a malaria, generated any where
and conveyed by the winds, can be transported to a distance of
three miles, as has been proved, there is no reason why it should
not travel much farther, or to any distance that can be assumed:
and if this be true of a clear wind, the case of a fog is even a
much stronger one; since there is little reason to doubt that the
individual parts of such fog, in any assumed mass, will retain their
relative places to each other, as perfectly after a journey of any
given number of miles, as they did at the point of production; and
if a portion of malaria has been united to a portion of fog, in the
marsh which produced both, or whence both have come, there is every
apparent reason why it should be found in that same portion at any
farther or assumed distance, because there is no cause for either its
dispersion or its decomposition.
A fog is a cloud, simply; and it is notorious that a single [p048]
cloud, and often of very small dimensions, will remain at rest
in the atmosphere, or travel very many miles without the loss of
its integrity; however we may imagine it assailed by the various
meteorological causes of destruction, as well as by mechanical
violence. This in itself proves the consistency with which a current
of wind preserves the relative positions of its integral parts;
because it is plain that a disturbance among these must disturb or
destroy the cloud which, in reality, forms a portion of that current,
as a gaseous body: and since that cloud is a mist, since it might
have been the very evening mist embodying a malaria, and since it
is its real vehicle and repository, it is plain that had it, or
any individual cloud, contained such a portion of malaria, it must
have had the power of transmitting that, and would actually have
transported it to any distance to which itself might travel. Thus, it
is evident, may a fog, generated in Holland, carry without difficulty
to the limits of its range, or to the coast of England, that malaria
which became entangled with it at its birth-place or in its passage;
and thus, I have little doubt, is the fact of those agues explained,
and this transportation to such distances established.
I cannot, at least, conceive any demonstration as to facts of this
nature more convincing, nor anything wanting to the proof; while
I may proceed to make some remarks on the east wind, and on fogs,
simply, because they concern this question.
The proof that it is a malaria in the fog, and not the fog itself,
which is the cause of disease, is evinced by the following fact;
while it ought surely to be unnecessary to say, that if fog alone
could produce such fever, water itself must be the poison: since a
fog is a cloud, and its constituents, when pure, are only atmospheric
air and water. No intermittents are ever produced on the western or
northern shores by the sea fogs, and for the plain reason, that there
is no land whence they arrive. The clouds of mountainous regions
do not produce fevers, though these also are fogs; and what forms
a most absolute proof of this is, that in Flanders, it is the fogs
which come with a southwest wind, or the southerly winds themselves,
which transport and propagate malaria and disease; while; as soon as
the winds shift, and blow from the sea, the fevers [p049] disappear,
though those particular winds are so charged with fog, as to darken
the whole country for days: and it will be found an invariable rule
all over the world, that when a fog is the apparent cause of disease,
or when an east wind is such, it is because these have been generated
in a land of marshes, or have traversed one; and that, under other
circumstances, or where no pernicious land lies in the way, they are
as innocent as any other fogs and winds, and that the hazard and the
suffering will arise from those, be they whatever they may, which
traverse pestilential lands.
But I must defer this particular and interesting subject to another
occasion, lest I make this article too long; and proceed to examine
some other circumstances connected with the transportation of malaria.
First, however, I must notice one fact as to this transportation from
Holland, partly because it is a necessary fact in the history of
malaria, and partly because it might be used as an argument against
the view which I have just given. The east winds of autumn are not
supposed to bring remittents, as those of spring bring agues, though
I cannot assert that this is absolutely true. Being assumed, the
solution is easy. If the winds of this nature in spring, are notedly
moist, and thus vehicles of malaria, the case is exactly the reverse
with the east winds of summer and autumn; or as the east wind may
be the most moist of winds, so may it be the most dry; while it is
a consequence of its extreme dryness, in fact, that it is always
the very cause of our burning summers. This is the history of our
last summers, and it is invariable, whether as it relates to seasons
or single days; and it is plainly owing to its permitting the more
ready transmission of the sun’s rays. That it is the very harmattan
of Africa, it is almost unnecessary to say; and as dry wind is not
a conductor of malaria, as that poison is in fact decomposed or
destroyed in these circumstances, daily and invariably, it is easy to
see why the remittents of Holland should not be transported, like its
intermittents, though even this may possibly happen under particular
circumstances.
To proceed; and to the next remarkable facts connected with the
propagation of malaria.—The most singular of these is its limitation,
or that yet unexplained property by which it is [p050] determined in
a particular direction, or confined to a particular spot, while it is
a piece of knowledge of some practical value. There is an appearance
of incredibility about many of these facts, and, accordingly, they
have not only been disbelieved but ridiculed, although nothing in the
whole history of this substance is better established.
With respect to direction, in the first place, it is remarked in
Italy, currently, that this poison will enter the lower stories of
houses, particularly with open windows, when the next above escape;
and hence, in many places, no one ventures to sleep on ground floors:
and the truth of this was confirmed in the barracks at Jamaica by Dr.
Hunter; as the cases of fever occurring among the men in the lower
rooms much exceeded those which happened in the upper ones. But I
am also informed, that in some places in Norfolk this peculiarity
is reversed; or that there are houses where it is remarked that the
ground-floors are safe, while no one can sleep in the upper stories
without hazard.
That malaria may in some manner be attached to the soil is also well
known by its effects, and especially in Italy. There it is remarked
that it is extremely hazardous to cut down certain bushy plants which
appear to entangle it, and that fevers are a frequent consequence of
such carelessness. Thus, also, does fever seize on the labourers who
may incautiously sit down on the ground, while they would escape in
the erect posture; being thus, indeed, sometimes suddenly struck with
apoplexy, which is one of the effects of this poison, or even with
death.
It has similarly been observed that it is often retained in the
shelter of drains, or in the ditches of fortifications; whence
frequent fevers among the sentries on particular guards, when the
other soldiers escape. And thus was it even proved at Malta, that it
was transported from the sea-shore, and thus lodged in a dry ditch of
the works at Valetta; all these facts being possibly to be explained,
by supposing it possessed of a greater specific gravity than the
atmosphere, or else attached to vapour thus weighty, exhibiting
effects analogous to those which carbonic acid displays in the
Solfatara.
But the circumstance most difficult of explanation is, that in
Rome, and numerous places in Italy, and even where it is [p051]
transported from a distance by the winds, not generated on the spot,
it is found, perennially, and through the whole course of successive
years, to occupy certain places, and to avoid, as constantly, others
quite near, and, as far as the eye can judge, equally exposed, and
in all respects similar. Thus, one side of a small garden, one side
of a street, or one house, will be for ever exposed to disease, or
uninhabitable, when, at a few feet or yards distant, the very same
places are as constantly free of danger: and thus it was found at the
village of Faro, in Sicily, that all the troops of our army quartered
on one side of the single street which formed it, were affected
by fevers, and suffered great mortality, while those on the other
remained in health.
But the most remarkable case of this nature known to me, is a
domestic one, and which rests on the testimony of thousands of
persons, or of the whole country, however incredible it may appear.
It is, that between Chatham and Brighton, including every town and
single house, and Sittingbourne among the rest, the ague affects the
left hand side of the turnpike road, or the northern side, and does
not touch the right side, though the road itself forms the only line
of separation.
We cannot as yet conjecture the cause of this very singular
circumstance or property, at least in cases of this nature;
though, under certain events of this kind, there are some facts
in meteorology that may offer a solution. These are the notorious
ones, that a hoar frost, or a dew, will sometimes be found most
accurately limited, both vertically and horizontally, by a definite
line; stopping, for example, at a particular hedge, and reaching to a
certain altitude on a tree: but for the other cases, we must yet wait
for a period of more accurate knowledge as to this singular substance.
There is now one circumstance of importance, relating to the
destruction or decomposition of malaria, which must not be passed
over, from the interest of the facts depending on it: this is,
that its propagation is checked by the streets of a crowded town,
and apparently owing to this very cause, decomposition. Thus it is
observed, that the fever never appears in the Judaicum of Rome, and,
similarly, that the crowded streets and the poor people escape, when
the opulent houses and open [p052] streets are attacked; and hence
the Villa Borghese, among many other palaces and opulent houses
in Rome, has been abandoned, while such desertion, being limited
exclusively to houses where the air is most open and free, naturally
excites wonder: the cause, however, is now plain; and thus it now
appears why it was that the Penitentiary in Westminster suffered
formerly from dysentery, originating in this cause, when no such
disease appeared among the neighbouring inhabitants.
And if this fact is of value as it may relate to the erection of open
streets in any place of this nature, it is most important to point
out what has been the continuous effect at Rome, as the ultimate
consequences threaten to be extremely serious.
It appears that from cutting down some forests which many years ago
occupied the declivities of the hills to the southward of Rome, the
malaria was let in upon that city from the Pontine marshes; and,
further, that the extirpation of a similar wood to the eastward had
let in the same poison upon another quarter. Thus it has been found
to enter the city through the Porta del Popolo, while, for many
years past, it has been gradually extending its influence through
the streets; leading annually and successively to the abandonment of
many houses and palaces, and still annually increasing and extending
its ravages; so as, at length, as I understand, to have even
become sensible at the Vatican. And the lines which it follows are
distinctly traced out by the inhabitants; while, as I have already
said, it is only the houses of the opulent which suffer, further than
as the abandonment of these may also influence the inferior ones in
their neighbourhood.
Whatever the original cause may be, and however the direction,
abstractedly, may be regulated by the winds and the forms of the
streets, or by local and fixed circumstances, it is plain that the
annual extension is the consequence of desertion, and that as the
inhabitants retire from before it, it acquires the means of making
a new step and a further progress; because thus they withdraw
those fires and smoke, or whatever else it be, dependent on human
crowds, which decomposes and destroys this substance. And hence it
must follow, that as Rome shall become still further abandoned and
depopulated, from want of industry, or from political feebleness
[p053] added to this cause, the effects must be expected to increase
in a sort of geometrical ratio; almost leading to the fear that
the whole city itself may, in time, fall a victim to it, or become
abandoned to the wolves and mosquitoes.
If I dare not inquire more minutely into the remaining circumstances
connected with the propagation of malaria, lest I should extend this
article to an inconvenient length, it is necessary now to offer
some remarks on prevention, and especially as it relates to this
circumstance—the propagation of the poison; since the rules for
prevention, as far as this relates to production, may be deduced from
what was said in a former paper on this subject, and relate chiefly
to the drainage of lands, and to other practices, more or less
obvious, which a little reflection will, without much difficulty,
deduce from what was there said.
It is plain, in the first place, that as far as the winds are
concerned, it is by opposing obstacles to their course that we must
attempt to counteract or divert their influence; and that, in this
case, it is through the use of trees alone that we possess any power.
Thus reversely, as in the case just stated, the cutting down of trees
and forests has often been a serious cause of diseases in certain
countries, by admitting a malaria to particular spots; though it is
easy to see that where any given spot suffers from malaria, through
condensation or confinement, the clearing away of these would be the
remedy, by attaining a free ventilation. To detail the particular
modes in which remedies may be applied through this species of aid,
is obviously unnecessary, and not easy, as it must depend on local
circumstances, differing for each place; but I may remark, as an
example in illustration of my meaning, that where, as in many of the
narrow and prolonged valleys of Greece, the sea shore is a marsh,
the remedy would be to plant a screen of trees beyond it, and thus
to prevent the sea winds from passing into the interior. And thus
did the ancient Romans compel the planting of trees on the shores
of Latium, to check the current from the Pontine marshes; rendering
groves sacred, under heavy penalties, and enacting other laws with
the same intentions.
With respect to such temporary precautions in these cases [p054] as
may concern armies in the field, or in camps, it is plain that they
will depend on attention to the courses and seasons of the winds;
while it would be abundantly easy to accumulate, from the histories
of campaigns, the most fearful examples of mortality produced by
neglect of these and similar precautions, and even down to almost
the very date at which I am writing: and there can be no hesitation
in saying, that an intimate and accurate knowledge of every thing
which concerns the production and propagation of malaria, forms a
most important branch in that information necessary to a soldier,
and above all to the quarter-master-general’s department and the
medical staff: while, did I dare to record but a very small portion
of the mortality experienced, not only in our own armies, but in
those of Europe at large, during even the last war, from ignorance
or neglect on this subject, it would, I believe, be found that it
almost equalled the mortality produced by the actual collision of
war itself. Walcheren will not soon be forgotten; if we have ceased
to think of our mortal Havannah expedition; and if a French army at
Naples was diminished by twenty thousand men, out of twenty-four, in
four days, from this cause; if Orloff lost nearly his entire army in
Paros; if Hungary has more than once destroyed ten times the number
of men by fever that it did by the sword,—these are but trifles in
the mass of reasons for saying, that no subject can well be more
important, and no knowledge much more necessary to the commander of
an army.
Some other points relating to prevention may deserve a few words
of notice, before I pass from this subject; if here, also, I must
be brief. Not to repeat the cautions founded on what relates to
the power of evening and morning, it has been asserted that the
use of a gauze veil will prevent the effect of malaria; and it is
not improbable that the air accumulated within that, may have the
power of decomposing the poison: it is an opinion, at least, which
is universal among the people in Malta, and very general in Spain
and Portugal. It is also found that fires and smoke are useful, and
especially on military service; the experiment having been tried on
a very large scale by Napoleon before Mantua, and on a smaller one
in Africa, with the most perfect success. With respect to [p055]
personal precautions, it is universally recommended to use wine and
a good diet, and especially never to leave the house in the evening
in situations peculiarly insalubrious, without the previous use of
wine or spirits; whence the universal practice of Holland in this
respect. Thus, also, narcotics prevent its influence; whence the wide
use of tobacco, of which the salutary effects appear to be most amply
established.
As to the tropical countries, there is here also one important
remark, which, from the great neglect of the fact, and its ruinous
consequences, appear particularly to demand a statement in this
place. It is the universal experience of the inhabitants, that the
attack of malaria, or the production of fevers, is aided by the use
of a full or animal diet; by the use of some particular articles of
food, such as butter; by excess in eating, generally; and, above all,
by eating in the heat of the day. This is not merely well known to
the negroes, but the fact is distinctly stated to travellers, and the
caution urged, however often it has been neglected, and especially
by our own countrymen. Of this, in particular, Major Denham is a
strong testimony; while he attributes his own exclusive preservation
to his having rigidly followed the recommendations of the natives,
which were always urged with the greatest earnestness. And if we
examine the causes of death, in most cases, of our African travellers
especially, I think there will be strong reasons for believing that
their lives have often been sacrificed to this very negligence
or obstinacy; while it is most evident that Niebuhr’s party, in
particular, owed the loss of their lives to what may be safely called
gluttony: and it is to be suspected that this will also explain the
loss of Captain Tuckey’s party; while, with respect to nations, it
has long been known that the English, the Dutch, and the northern
voracious people in general, who habitually indulge themselves in the
customs of their original country as tropical colonists, have always
been greater sufferers from the effects of those climates than the
French and the Spaniards, and apparently from this very difference.
And there seems little doubt, generally, that the vegetable diet of
Africa and Hindostan is the best security against the evil influence
of those climates, and that the chief sufferings of our [p056] own
colonists arise from transferring to those situations their ancient
habits of full and free living.
As I must not prolong this subject much further, I shall now pass to
a few remarks, but very brief ones, on the geography of malaria as
it relates to those parts of the continent of Europe most frequented
by English travellers; not daring to take room for actual and
useful information on that head, but wishing to point out merely
the importance of such geographical knowledge to those persons, on
account of the hazards which they so universally incur from that
ignorance or neglect, and of the great mass of suffering, and also
of mortality, which has been the lot of persons who had resorted to
those climates as travellers, or migrating residents, from various
motives, and not unfrequently with views to health. How often health
has been lost where it was sought, will be but too apparent to any
one who has chanced to possess an extensive acquaintance of this
nature.
Of Italy I can but afford to say generally, that except at a very
few points where the Alps or Apennines reach the sea, the whole of
its shores are pestilential, and often to such a degree as to lead
to their entire desertion, more frequently to their abandonment
in summer. And to avoid wet lands, or low lands, is not always a
sufficient precaution; since the most pestilential parts of the
maremma of Tuscany are dry, and since the annual mortality of Sienna
from fevers, even without epidemics, is one in ten. In the north of
Italy, the great plain is similarly insalubrious; though the more
unhealthy district does not commence until we arrive at Mantua,
extending thence to the sea. Of the Mediterranean islands, I can
only afford room to say, that the same rule holds good as to the
sea coasts, while the entire of Greece in the same circumstances
is similarly unhealthy, and subject to autumnal fevers in as great
a degree as the worst parts of Italy. The same is true of Spain
and Portugal, and the same rule also will be a guide; namely, that
malaria is to be expected in all the flat grounds, even when under
cultivation, and at all the exits of rivers on the sea, even though
no marshes should be present: and if I were desirous to name any
tract of land in Spain peculiarly [p057] insalubrious, it would be
the province of Valencia; while Carthagena is almost invariably fatal
even to those who, as labourers, are compelled to resort to it for
the needful work of its port, even during a few days.
Of France, little as it has hitherto been suspected by those who,
associating the term malaria with Italy, have been accustomed to
consider it as peculiar to that country, it would scarcely be untrue
to say that it contains as large a portion of insalubrious territory
as Italy itself, and produces fever and disease of as great severity
and extent, not merely on its sea coasts, but over very extensive
tracts in its interior. And this insalubrity may be conjectured,
when there are entire districts in which the average of life does
not exceed twenty, and in which the entire people are diseased from
their births to their graves. Such tracts are found chiefly on the
course of the Loire, and some other of the great rivers; and among
them, Bresse in the Lyonnais, the plain of Forez, and Sologne in the
Orleannais, are of the most notorious; while the coasts of Normandy,
and the whole of low Britanny, are similarly subject to eternal
intermittents, or to epidemic seasons of autumnal fevers, amounting
to absolute pestilences. And how English families have suffered in
this country from the incautious choice of residences in such places,
will be easily ascertained by whoever shall be at the trouble of
making the necessary inquiries.
But as I dare not pursue this extensive subject, I can only suggest
to our countrymen the utility of making themselves acquainted with
this matter, and with this dangerous geography, before encountering
the hazards which await them; while to physicians I need still less
name the necessity of that knowledge, since it is so often their
duty to choose and recommend for their patients, and since no man
can feel much at his ease who finds that he has sent into a land of
malaria the patient who has already been suffering from its diseases,
or that where he speculates on the cure of a consumption, that
cure is attained through the death of the patient, at Avignon, or
at Poitiers, or Nantes, or in some or other of the numerous places
subject to this most fearful poison.
It remains only to give a brief enumeration of the diseases [p058]
which are the produce of malaria, and of the general condition of
the inhabitants in the countries subject to it. With respect to this
latter, the most remarkable general fact is the contracted duration
of life. In England, the average may, if not very accurately, and
indeed considerably under the mark, be taken at 50; and when in
Holland it is but 25, it follows that the half of human life is
at once cut off by this destructive agent. In the parts of France
to which I have alluded, it becomes as low as 22 and 20, and
Condorcet, indeed, has calculated it as low as 18. With this, very
few attain the age of 50; and in appearance and strength, this
term is equivalent to 80 in ordinary climates; while 40 forms the
general limit of extreme and rare old age. The period of age, indeed,
commences after 20; and it is remarked, in particular, that the
females become old in appearance immediately after 17, and have, even
at 20, the aspect of old women. In many places, even the children are
diseased from their birth; while the life which is dragged on by the
whole population, is a life of perpetual disease, and most frequently
of inveterate and incurable intermittents, or of a constant febrile
state, with debility, affections of the stomach, dropsy, and far more
than I need here enumerate.
While the countenances of the people in those countries are sallow
or yellow, and often livid, they are frequently so emaciated as
to appear like walking spectres, though the abdomen is generally
enlarged, in consequence either of visceral affections or dropsy.
With these, rickets, varices, hernia, and, in females, chlorosis,
together with scorbutic diseases, ulcers, and so forth, are common;
and it is even to be suspected that the cretinage may depend on this
cause, since goitre is also one of the results of malaria, and since,
in the Maremma of Tuscany, idiotism is a noted consequence of this
pestilential influence.
The general mental condition is no less remarkable; since it consists
in an universal apathy, recklessness, indolence, and melancholy,
added to a fatalism which prevents them from even desiring to better
their condition, or to avoid such portion of the evils around them
as care and attention might diminish: and while it is asserted that
even the moral character becomes [p059] similarly depraved, I prefer
a reference to Montfalcon for a picture which it would not be very
agreeable to transcribe.
As to the absolute or positive diseases, besides those which I have
already named, I need scarcely say that remittent and intermittent
fevers, under endless varieties and types, form the great mass; and
next in order to them, may be placed dysentery and cholera, together
with diarrhœa. To these I must also add, those painful diseases of
the nerves, of which sciatica stands foremost, and the remainder of
which may be ranked under the general term of neuralgia; and further,
a considerable number of inflammatory diseases of a more or less
remittent type, among which rheumatism under various forms is the
most general, and the intermittent ophthalmia the most remarkable.
Lastly, I must include the various paralytic affections; since
apoplexy is one of the primary and direct consequences of malaria, as
various paralytic affections are the produce of intermittent, or the
consequences of the diseases of the nerves which are associated with
it.
It is still a curious and interesting fact, that this poison affects,
in an analogous manner, many different animals, and appears, in
reality, to be the cause of all the noted endemics and remarkable
epidemics which occur in the agricultural animals in particular.
This has been noticed even by Livy: and in France and Italy it is
equally familiar that the severe seasons of fever among the people
are similarly seasons of epidemics to black-cattle and sheep,
while the symptoms are as nearly the same as they could be in the
circumstances, and the appearances on dissection also correspond.
Thus also does it appear probable, that the rot in sheep is actually
the produce of malaria, as is indeed the received opinion among
French veterinarians; while Mr. Royston has observed that the animals
of this class are subject to distinct intermittents.
And while it is not less familiar in the West Indies, and in Dominica
particularly, that dogs suffer from a mortal fever in the same
seasons and periods as the people, the epidemic always breaking out
in them first, I have the most unexceptionable medical evidence of
the occurrence of a regular and well-marked tertian in a dog; that
evidence consisting in the concurring decision of many surgeons, by
whom the case was [p060] frequently examined, during a very long
period. But it is time to terminate a paper, which, if it is but a
sketch of an important subject, will at least convey to those to
whom malaria has not hitherto been an object of attention, a general
notion of the leading particulars which appertain to its natural
history.
J. M.
_Elements of Chemistry, including the recent Discoveries and
Doctrines of the Science. By_ Edward Turner, M.D., F.R.S.E., &c.,
&c. _Edinburgh_, 1827.
This is a closely-printed octavo of 700 pages, and presents us with
something more original, clear, and accurate than we have lately met
with in modern chemistry. It comprehends a perspicuous view of the
present state of chemical science; and, as far as its limits admit,
the theoretical parts are, with some exceptions, well and distinctly
worked out; nor are the practical details of manipulation neglected,
though they evidently occupy a secondary place in our author’s
estimation. To the arrangement we must at once decidedly object—it is
indeed evident that Dr. Turner has pitched upon Dr. Thomas Thomson
as his _magnus Apollo_, and here and elsewhere the book is tainted
accordingly.
This work is divided into four principal parts;—the first relates
to what Dr. Turner, following his prototype, Dr. Thomson, calls
_imponderables_, and a definition of them follows, which leads
us to suggest the term _inexpressibles_, as equally appropriate.
But, waiving this objection, the details relating to them are well
and clearly given. Thus, after some prefatory remarks upon the
subject of caloric or heat, (we prefer the latter term, and cannot
allow its ambiguity,) its modes of communication are considered,
first, as being _conducted_ through bodies, and then as _radiating_
through free space. In regard to the theories affecting the
latter, our author wisely, as we think, prefers that of Prevost
to that of Pictet. The _effects_ of heat are next discussed, such
as _expansion_, including an account of the thermometer, and
of the relative capacities of bodies for heat; _liquefaction_,
_vaporisation_, _ebullition_, _evaporation_, and the _constitution of
gases_ and lastly, the sources of heat are mentioned, but the details
are referred to other parts of the work. [p061]
_Light_ is next treated of, but we think too hastily, and too much in
the abstract.
Now the subjects of heat and light are obviously of the utmost
importance to the chemical philosopher, and they are very extensive,
and intricate and difficult to treat of, inasmuch as the writer is
necessarily upon the confines of chemical and mechanical philosophy,
and should be expert in both. When, therefore, elementary works on
chemistry are so written and arranged as to serve as text-books for
lectures, and indexes of reference to more accurate information, we
can make due allowance for brevity; but when the subject is intended
to be formally and completely developed to the student, independent
of other ocular and oral aids, much more extensive description and
detailed explanation is required, than is to be found either in
our author’s “Elements,” or in any other analogous condensation of
chemistry. Dr. Henry understands the requisite mode of conveying
information in these cases better than most writers; and when he
takes pains, and speaks for himself, has the talent of being brief,
and at the same time minute, deep, and clear. Dr. Ure, as his
dictionary shows, is an eminent example of such a writer—_he_ of
course is neglected, where, as with our author, Dr. Thomson is in the
ascendant; but the article caloric, in his dictionary, will at once
explain and illustrate our meaning, and would furnish an admirable
foundation for a detailed essay or treatise upon the subject. So
extensive, indeed, are the precincts of chemistry now becoming, that
either our _systems_ must become very voluminous, or we must adopt
the plan, which to us appears preferable, of distinct treatises upon
different branches of the science. Thus, a separate work on heat and
light; another on electricity and magnetism; another on attraction
and the theory of combination; a fourth on the constitution and
properties of the unmetallic elementary bodies; a fifth on the metals
and their compounds; a sixth on vegetable, and a seventh on animal
chemistry and physiology; an eighth on the chemistry of the arts;
and lastly, a treatise on chemical manipulation in general, would
include all that appears essentially requisite; and as no one is
supposed to be equally well versed in all branches of the science, or
in all details of the art, an opportunity of selection would thus be
afforded, so that each writer might choose that particular department
which he is most accurately acquainted with, or which has formed
his favourite study. Mr. Faraday has already, as may be said, led
the way in such a plan, by the publication of his _Chemical [p062]
Manipulation_, a work hitherto exceedingly wanted in the laboratory,
equally useful to the proficient and to the student, and eminently
creditable to the industry and skill of the author, and to the school
whence it emanates. We shall of course take an early opportunity of
introducing this book in a more formal way to the attention of our
chemical readers.
In looking over Dr. Turner’s first and second sections on caloric and
light, in the _Elements_ now before us, we find little but brevity
to complain of;—there are, however, one or two trifling historical
inaccuracies: thus, at page 14, the discovery of _invisible_ heating
rays is ascribed to Saussure and Pictet; but it is, in fact, of much
more remote origin—it was well known to the Florentine academicians,
and we may even trace the idea in Lucretius, (_De Rerum Naturâ_, lib,
v. 1, 609.)
Forsitan et rosea Sol alte lampade lucens
Possideat multum _cæcis fervoribus ignem_
Circum se, _nullo qui sit fulgore notatus, &c._
At page 31 we have an account of Wedgwood’s pyrometer, which is said
to be “little employed at present, because its indications cannot be
relied on;”—the fact is, that it is never used, and that we owe to
Sir James Hall ample reasons for placing no confidence in it.
The subject of _specific heat_ is clearly explained, and so are
the phenomena of liquefaction and evaporation. In regard to the
constitution of gases, the author remarks, that the experiments
of Sir H. Davy and Mr. Faraday on the liquefaction of gaseous
substances, appear to justify the opinion that gases are merely the
vapours of extremely volatile liquids. Mr. Faraday has proved this
in regard to several of the gases, and analogy leads us to apply it
to the rest;—but what share Sir H. Davy had in the discovery, we
know not; for Mr. Faraday actually condensed chlorine into a liquid
before Sir H. had heard or thought about the matter. _Light_, and
its phenomena as connected with chemistry, is superficially passed
over in the second section, and the third brings us to the important
article “Electricity.”
We are willing to admit that the subject of electricity is a very
difficult one for the chemist to deal with—he must necessarily say
much upon it, and is equally obliged to omit abstract details which
are often necessary to its explanation, and yet too prolix and bulky
for an elementary chemical work. So that it requires considerable
acquaintance with the subject to give a perspicuous and yet concise
abstract, [p063] such as may be useful to the student. Dr. Turner
has not been very successful in effecting this _desideratum_, and
has unnecessarily introduced two sections, the one on electricity,
the other on galvanism. He also talks of the “science of galvanism,”
which is in bad taste, and erroneously asserts that the energy of the
pile is proportional to the degree of chemical action which takes
place; a statement by no means correct, inasmuch as the energy of De
Luc’s column is directly proportional to the number of alternations,
and appears entirely independent of chemical action; and again, a
series of 2000 plates, arranged in the usual Voltaic apparatus, when
perfectly bright and clean, and the cells filled with distilled water
only, give a much more powerful shock, and cause a greater divergence
of the leaves of the electrometer than when the apparatus is charged
with diluted acids. Here, those very singular phenomena, which
electricians distinguish by the terms _quantity_ and _intensity_,
appear perfectly distinct; and between these our author does not
sufficiently discriminate, but jumbles the whole under the term
_activity_. In describing the chemical energies, too, of the pile, or
its decomposing powers, the Doctor entirely overlooks the important
and curious influence of water. He says that acids and salts are all
decomposed, without exception, one of their elements appearing at one
side of the battery, and the other at its opposite extremity; (_i.
e._ we presume, at its positive and negative poles.) But the fact is,
that, excepting where it merely acts as a source of heat, nothing
is decomposable by electricity without the intervention of water;
the hydrogen and oxygen of which respectively accompany the elements
of the other compounds. Not an atom of potassium can be obtained
unless the potassa be moistened; nor can any salt be decomposed
except water be present. Sir Humphry says, it is required, to render
the substance a conductor; but its operation is more recondite, and
there is something mysterious and still unexplained in the uniform
appearance of hydrogen and oxygen at the opposite poles, when far
apart in water, and in all other cases of true polar electro-chemical
decomposition. At page 86, the unfortunate protectors of ships’
bottoms are introduced—a subject about which the less is said the
better;—and, as to electro-magnetism, it is merely mentioned as to
its leading phenomena, in the space of three or four pages; nor
is anything new suggested upon the “Theory of the Pile,” as it is
called, which concludes the subject, and which is dismissed in the
brief limit of a page and a half. [p064]
The second part of Dr. Turner’s work is said to comprise “Inorganic
Chemistry,” and therefore embraces a very extensive field of inquiry.
To the _arrangement_ we have already objected; and many of the
typographical and verbal errors that occur, have been noticed in a
contemporary Journal, so that we shall chiefly attend to the details
of the sections.
Under the head, “Affinity,” some of the leading facts and doctrines
of chemical attraction are perspicuously set forth; but we could have
wished that a variety of exploded opinions and erroneous notions had
been altogether passed over, as they occupy space which might have
been better employed, and can never prove of any other use to the
student than to show him the errors and fallacies to which acute
philosophers are sometimes liable. Of this kind, especially, are
Berthollet’s notions upon the subject of affinity. The doctrine of
definite proportion is, on the whole, well and clearly explained; but
it would have been much better and clearer, had Dr. Turner confined
himself to facts, and meddled less with opinions concerning their
cause; he is moreover, in many respects, historically inaccurate. He
ascribes much to Dalton that honestly belongs to Higgins;—is much
too merciful to Berzelius and his CANONS; and lenient beyond all
endurance to the plagiarisms of “Dr. Thomson’s admirable Treatise on
the first Principles of Chemistry.”
In the third and following sections, the simple non-metallic
substances are described in an order of arrangement which must be
very perplexing to the student; otherwise the details are well
given, except that here and there the line between theory and fact
is not sufficiently marked. Thus we are told that “hydrogen is
exactly 16 times lighter than oxygen, and _therefore_ that 100 cubic
inches _must_ weigh 33.888/16, or 2.118. Its specific gravity is
consequently 0.0694, as stated some years ago by Dr. Prout.” Now this
is a theoretical deduction, founded upon the specific gravity and
constitution of ammonia, (and not upon the composition of water,) and
probably correct as applied to _pure_ hydrogen;—but if we weigh the
gas, as usually obtained, even with the utmost caution, and of the
utmost purity, we shall never procure it so light as here stated,
notwithstanding all the learning and argument that our worthy friend,
Dr. Thomas Thomson, has issued upon the subject in his various
essays in the Annals, and in his _magnum opus_. We also object to
the stress which is often laid upon the whims of individuals, and
upon [p065] exploded opinions; instances of which will occur to the
reader under the subject of the composition of nitrogen, and the
constitution of the atmosphere. We further caution our author against
admitting hints, allusions, and inuendos as to the possibility of
future inventions and discoveries, as claims upon the merits of such
discoveries, when they are actually made. Berzelius has talked a vast
deal of nonsense about the composition of nitrogen; and should that
discovery ever be made, he will doubtlessly assume the credit of
having suggested the steps which led to it. Some foolish persons are
apt to think that the Marquis of Worcester was the inventor of Watt’s
steam-engine, because he said he had means of raising water by steam,
in his _Century of Inventions_; and we have heard that an eminent
chemist of the present day considers himself entitled to all the
merit that may belong to Mr. Brunel’s carbonic acid engine, because
he had previously stated the possibility of such an application of
Mr. Faraday’s important discoveries. The fact is, that these are
woeful days for science; all the good feeling and free communication
that used to exist among its active cultivators in this country, has
given way to petty jealousies and quibbling scandal; one person is
exalted for the purpose of depreciating another; and those causes of
disgust, which some years ago induced one of our most amiable and
able men of science to quit the field, and even leave the country,
are becoming daily more prevalent. Were it not an invidious task, we
could easily explain and unfold the sources of all this mischief, and
shall indeed feel it our duty so to do, should not matters in due
time take a more favourable turn; but the task is at once serious
and disagreeable, and we therefore postpone it, in the hope of more
favourable events. We really believe that, had it not been for the
scientific conversationes held during the last season at the houses
of a few private gentlemen connected with the learned societies,
and more especially the weekly meetings at the Royal Institution,
which kept up a friendly intercourse among those who were willing
to profit by it, that the whole scientific world would have been at
loggerheads, and in that state of anarchy of which the evils may be
learned by a short residence at a “northern seat of learning.”
The main object of this digression is to deprecate _party_ in
science; and we were led to it by observing, or thinking that we
observe, something of such a tendency in the writer whose book is
before us—we hope we are mistaken.
The next section comprises “the compounds of the simple [p066]
non-metallic acidifiable combustibles with each other.” It includes
the important subject of ammonia, of the varieties of carburetted
hydrogen, sulphuretted and phosphuretted hydrogen, and cyanogen
and its compounds. The metals are then treated of, and to these
succeed their salts; and though the execution of this part of the
work betrays some haste, it shows also considerable reading, and
some originality: the general views are well and clearly sketched,
but there are many points upon which we are entirely at variance
with our author; and we more especially object to his account of the
action of chlorides upon water, and to his notions concerning the
“muriates of oxides,” a class of compounds of which, with one or two
exceptions, we are disinclined to admit the existence. If common
salt be a _chloride_ of _sodium_, and experiment obliges us so to
regard it, what is there in its aqueous solution that should lead us
to consider it as containing a _muriate_ of _soda_; what evidence of
any new arrangement of elements? Dr. T. is certainly in mistake, when
he says, “for all practical purposes, therefore, the solution of a
metallic chloride in water may be viewed as the muriate of an oxide,
and on this account I shall always regard it as such in the present
treatise.” This inconsiderate dogma taints much of the reasoning
upon the chlorides, &c., and is manifestly culled in the Thomsonian
school, though we have indeed heard that a Professor at Edinburgh
thus addresses his pupils upon the above subject: “The elaborate
researches of the illustrious Davy have taught us that common salt
is a binary compound of chlorine and sodium, a chloride, therefore,
or a chloruret of sodium. But it is only chloride of sodium whilst
quiescent in the salt-cellar; for no sooner does it come into
contact with the salivary humidity of the fauces, than, by the play
of affinities, which I have elsewhere explained, the sodium becomes
soda, and the chlorine generates muriatic acid;—that, therefore,
which upon the table is chloride of sodium, is muriate of soda in
the mouth; and this again, when desiccated or deprived of humidity,
retrogrades into its former state.”
Dr. Turner again falls into error, as we humbly conceive, in calling
certain salts, such, for instance, as those of the peroxide of iron,
_sesquisalts_, a term properly applied in those cases only where one
proportional of a protoxide unites with one and a half of an acid,
such for instance as the _sesquicarbonate of soda_, &c., but in the
sesquisulphate of iron, one proportional of the peroxide contains
1.5 of oxygen, and [p067] necessarily, therefore, (according to
Berzelius’ canon, if the Doctor pleases,) requires 1.5 of acid to
convert it into a salt; just as the commonly constituted peroxides
(containing two proportionals of oxygen) require two of acid. Dr.
Thomson, with all his nomenclatural pretensions, has fallen into the
same error.
The part of our author’s work which treats of the chemistry of
organic bodies is, upon the whole, an unexceptionable and accurate
epitome of that complicated branch of the science. It has its
inaccuracies, but they apparently arise out of the difficulty of
condensing into the space of a few pages, matter which, as we have
elsewhere remarked, would require an ample volume for its extended
and perspicuous details.
In our hasty account of this work, we have rather dwelt upon its
defects than its merits, in the hope of seeing another and more
extended edition, free from what we consider as serious obstacles
to the success and usefulness of the present production. We hope
that Dr. Turner will not feel offended at the freedom with which
our remarks are offered. We are anxious that a writer of such good
information should be induced to think for himself; at least, that
he should accurately weigh the pretensions, and inquire into the
originality of those views and researches upon which he bestows such
unqualified and, in our opinion, undeserved praise, and to which he
assents with a facility unbecoming one who evidently possesses the
means of testing their merits.
_Experiments on Audition_.
[Communicated by Mr. C. Wheatstone.]
The recent valuable experiments of Savart[23] and of Dr. Wollaston
have added to our stock of information several important and
hitherto unnoticed phenomena relating audition; but, notwithstanding
the investigations of these distinguished experimentalists, and
though the physiology of the ear has been an object of unceasing
attention for many centuries, yet we are far from possessing a
perfect knowledge of the functions of the various parts of this
organ. The description of new facts illustrative of this subject
cannot, therefore, be devoid of interest; [p068] and though I do not
anticipate that the observations contained in this communication will
lead to any important results, their novelty may claim for them some
attention from the readers of your Journal.
§ 1.
If the hand be placed so as to cover the ear, or if the entrance
of the meatus auditorius be closed by the finger without pressure,
the perception of external sounds will be considerably diminished,
but the sounds of the voice produced internally will be greatly
augmented: the pronunciation of those vowels in which the cavity of
the mouth is the most closed, as _e_ _ou_, &c., produce the strongest
effect; on articulating smartly the syllables _te_ and _kew_, the
sound will be painfully loud.
Placing the conducting stem of a sounding tuning-fork[24] on any part
of the head, when the ears are closed as above described, a similar
augmentation of sound will be observed. When one ear remains open,
the sound will always be referred to the closed ear, but when both
ears are closed, the sound will appear louder in that ear the nearer
to which it is produced. If, therefore, the tuning-fork be applied
above the temporal bone near either ear, it will be apparently heard
by that ear to which it is adjacent; but on removing the hand from
this ear (although the fork remains in the same situation) the sound
will appear to be referred immediately to the opposite ear.
In the case of the vocal articulations, the augmentation is
accompanied by a reedy sound, occasioned by the strong agitations
of the tympanum. When the air in the meatus is compressed against
this membrane by pressing the hand _close_ to the ear, or when
the eustachian tube is exhausted by the means indicated by Dr.
Wollaston, the reedy sound is no longer heard, and the augmentation
is considerably diminished. The ringing [p069] noise which
simultaneously accompanies a very intense sound, proceeds from the
same cause, and may be prevented by the same means. This ringing may
be produced by applying the stem of a sounding tuning-fork to the
hand when covering the ear, or by whistling when a hearing trumpet
is placed to the ear. As a proof that the resulting augmentation,
which, when great, excites the vibrations of the tympanum, is owing
to the reciprocation of the vibrations by the air contained within
the closed cavity, it may be mentioned, that when the entrance of the
meatus is closed by a fibrous substance, as wool, &c., no increase is
obtained.
If the meatus and the concha of one ear be filled with water, the
sounds above-mentioned will be referred to the cavity containing the
water in the same way as when it contained air, and was closed by
the hand; it will be indifferent whether any partition be interposed
between the cavity and the external air; as the water is equally well
insulated by a surface of air as by a solid body.
§ 2.
The preceding experiments have shown, that sounds immediately
communicated to the closed meatus externus are very greatly
augmented; and it is an obvious inference, that if _external_ sounds
can be communicated, so as to act on the cavity in a similar manner,
they must receive a corresponding augmentation. The great intensity
with which sound is transmitted by solid rods, at the same time that
its diffusion is prevented, affords a ready means of effecting this
purpose, and of constructing an instrument, which, from its rendering
audible the weakest sounds, may with propriety be named a Microphone.
Procure two flat pieces of plated metal, each sufficiently large
to cover the external ear, to the form also of which they may be
adapted; on the outside of each plate directly opposite the meatus,
rivet a rod of iron or brass wire about 16 inches in length, and
one-eighth of an inch in diameter, and fasten the two rods together
at their unfixed extremities, so as to meet in a single point. The
rods must be so curved, that when the plates are applied to the
ears, each rod may at one end be perpendicularly inserted into its
corresponding plate, and at the other end may meet before the head in
the plane of the mesial [p070] line. The spring of the rods will be
sufficient to fix the plates to the ears, but for greater security
ribands may be attached to each rod near its insertion in the plate,
and be tied behind the head.
[Illustration: untitled, Microphone]
A more simple instrument may be constructed to be applied to one ear
only, by inserting a straight rod perpendicularly into a similar
plate to those described above.
The Microphone is calculated only for hearing sounds when it is in
immediate contact with sonorous bodies; when they are diffused by
their transmission through the air, this instrument will not afford
the slightest assistance.
It is not my intention in this place to detail all the various
experiments which may be made with this instrument, a few will
suffice to enable the experimenter to vary them at his pleasure.
1. If a bell be rung in a vessel of water, and the point of the
microphone be placed in the water at different distances from the
bell, the differences of intensity will be very sensible. 2. If
the point of the microphone be applied to the sides of a vessel
containing a boiling liquid, or if it be placed in the liquid itself,
the various sounds which are rendered may be heard very distinctly.
3. The instrument affords a means of ascertaining, with considerable
accuracy, the points of a sonorous body at which the intensity of
vibration is the greatest or least; thus, placing its point on
different parts of the sounding board of a violin or guitar, whilst
one of its strings is in vibration, the points of greatest and least
vibration are easily distinguished. 4. If the stem of a sounding
tuning-fork be brought in contact with any part of the microphone,
and at the same time a musical sound be produced by the voice, the
most uninitiated ear [p071] will be able to perceive the consonance
or dissonance of the two sounds; the roughness of discords, and the
beatings of imperfect consonances, are thereby rendered so extremely
disagreeable, and form so evident a contrast to the agreeable
harmony and smoothness of two perfectly consonant sounds, that it is
impossible that they can be confounded.
§ 3.
Apply the broad sides of two sounding tuning-forks, both being
unisons, to the same ear; on removing one fork to the opposite ear,
allowing the other to remain, the sensation will be considerably
augmented.
It is well known, that when two consonant sounds are heard together,
a third sound results from the coincidences of their vibrations;
and that this third sound, which is called the grave harmonic, is
always equal to unity, when the two primitive sounds are represented
by the lowest integral numbers. This being premised, select two
tuning-forks, the sounds of which differ by any consonant interval
excepting the octave; place the broad sides of their branches, while
in vibration, close to one ear, in such a manner that they shall
nearly touch at the acoustic axis, the resulting grave harmonic will
then be strongly audible, combined with the two other sounds; place
afterwards one fork to each ear, and the consonance will be heard
much richer in volume, but no audible indications whatever of the
third sound will be perceived.
§ 4.
Very acute sounds, such as the chirping of the gryllus campestris,
&c., are rendered inaudible by exhausting the air from the Eustachian
tube, and thereby producing a tension of the membrane of the
tympanum; the different thicknesses or tensions of this membrane
may therefore occasion that diversity of the limits of audibility,
with regard to the acute sounds which Dr. Wollaston has pointed out
as existing in different individuals; if so, it would be desirable
to ascertain this limit in individuals in whom the tympanum is
perforated, or destroyed.
§ 5.
When the auricula is brought forward, all _acute_ sounds are rendered
much more intense, but no sensible difference is [p072] perceived
with regard to the grave sounds. The _higher_ tones of glass
staccados, or of an octave flute, the ticking of a watch, all kinds
of sibilant sounds, &c. are thus greatly augmented: the experiment
is easily tried, by whistling very shrill notes. A still greater
augmentation of the acute sounds is obtained, by placing the hands
formed into a concave behind the ears, and by bending downwards the
upper part of the auricula, so as to obtain a more complete cavity.
§ 6.
I will conclude with the following observation: I had, in consequence
of a cold, a very slight pain in my left ear; on sounding the regular
notes of the piano-forte, C^3 and C^4 were much louder than the
others, and the loudness was much increased, by placing the hand
in the manner above described to the left ear. When it was pressed
close, or when the Eustachian tube was closed, the intensities of
all the notes were equalized. I attribute this affection to the
diminished tension of the membrana tympani, which was again increased
by the operation described.
FOOTNOTES:
[23] Recherches sur les usages de la membrane du tympan et de
l’oreille externe; par M. Felix Savart. _Annales de Chimie_, tom.
xxvi. p. 1.
[24] The tuning-fork consists of a four-sided metallic rod, bent so
as to form two equal and parallel branches, having a stem connected
with the lower curved part of the rod, and contained within the
plane of the two branches. The branches are caused to vibrate by
striking one end against a hard body, whilst the stem is held in the
hand. The sound produced by this instrument when insulated is very
weak, and can only be distinctly heard when its branches are brought
close to the ear; but instantly its stem is connected with any
surface capable of vibrating, a great augmentation of sound ensues
from the communicated vibrations. The facility of its insulation and
communication renders it a very convenient instrument for a variety
of acoustical experiments.
_On the Petromyzon Marinus_.
On entering the harbour of Dublin a few weeks ago, we were becalmed
off the Hill of Howth, and to pass the tedious time until a breeze
sprung up, we found some lines on board, and began to fish from the
quarter-deck. We caught a number of grey gurnet; but our attention
was particularly attracted by a pull of uncommon force on one of
the lines. Having rendered assistance to the person who held it, we
were all astonished to see rise out of the water a large fish, with
apparently a double body, which, after floundering on the surface
of the water, we pulled on deck. On examining this phenomenon for
a short time, we were again surprized to see it separate into two
parts; and then found that there were _two_ large fish taken up on
the same hook, the head of one having been buried under the throat
of the other, to which it had firmly attached itself. When separated
by force, it wiggled about on the deck with extraordinary strength
and agility, and again darted on its prey, to which [p073] it adhered
so firmly, that it required very considerable exertion to detach
it; for it suffered itself to be raised up by the tail, and shaken,
still holding the other fish suspended from its jaws. When finally
separated, it showed great ferocity, darting at every thing near it,
and at last seizing the deck, which it held very fast, writhing with
its tail and body as if in the act of tearing it to pieces. When
detached, its teeth left a deep circular impression on the wood, the
fibres of which were drawn into the cavity of its jaws, so as to be
raised up in the form of a cone. I now directed, that it should be
put into a bucket of sea water, in the hope of preserving it alive
until we arrived in Dublin, but it died in a shorter time than could
be expected, from the energy and activity it had displayed, long
after the other fish was dead. We had handled it very roughly, and so
perhaps had mortally hurt an animal otherwise very tenacious of life.
[Illustration: untitled, Fish]
On examining the fishes, I found that which had taken the hook,
was the _gadus Polachius_, or whiting Pollack. It was about two
feet long, and it is probable its active enemy had fastened [p074]
on it after it had been hooked; if _before_, it would indicate an
extraordinary insensibility to pain in an animal that could attend to
the calls of appetite, whilst another was preying on its vitals. The
fish which had fastened on the pollack, was the _petromyzon marinus_,
or sea lamprey. It was nearly three feet long, and resembled a large
eel in shape. Its general colour was a dull brownish olive variegated
with bluish blotches; the back darker, and the belly paler, inclining
to yellow. The eyes were small, and the mouth large and oval; but
when distended, circular. The inside of the jaws was deeply concave,
and studded with circular rows of sharp triangular teeth, that issued
from corresponding orange-coloured papular protuberances, which
formed the gums; the tongue was short and crescent-shaped, furnished
with a row of very small teeth round the edge. On the top of the
head was a small orifice, or spout-hole, from whence it discharged
the superfluous water taken at the mouth. But the circumstance that
more particularly distinguished it, was that which gave rise to the
vulgar error that it had sixteen eyes. On either side of the neck,
commencing just below the real eyes, was a row of seven equidistant
spiracles exactly resembling eyes; they are, however, holes lined
with a red membrane, and all opening into the mouth, an apparatus to
supply the place of gills, whose functions are to extract oxygen from
the water, and so perform the office of lungs in aquatic animals. It
had two dorsal fins, one on the lower part of the back, narrow, with
a roundish outline; the other commencing where the first terminated.
The spine was cartilaginous, without processes. The pericardium,
containing a small heart, was a remarkably strong membrane, and the
liver was as green as grass.
This fish is not uncommon in the North Seas, though it most abounds
in the Mediterranean, where, from earliest times, it was esteemed a
luxurious dish. Fish-ponds were purposely constructed to preserve
it. On our coast, Pennant observes, that it is found most frequently
at the mouth of the Severn, which river it sometimes ascends, where
it is occasionally taken, firmly attached to a stone by its mouth,
while its tail and body are waving freely to the current. Its
adhesion at such times is so strong, that it may be lifted with a
stone of twelve pounds weight appended to its mouth. This faculty
is owing to its [p075] power of suction; while the circumstance of
its circular jaws coming in close contact with the surface of the
body excludes the external air within the cavity of the mouth, and
so adheres like the hand placed on the cup of an air-pump. It is
from this remarkable property, that its scientific name has been
imposed[25]. Its vulgar name, lamprey, from lampetra, has a similar
derivation. By the Romans it was named muræna. As this fish was well
known and highly prized by the ancients, there is none that has been
so frequently described and alluded to. Aristotle, Pliny, Tacitus,
Columella, Ælian, Seneca, and Oppian, have mentioned its properties
and habits, which correspond exactly with those I have described
above. Pliny says, in the northern parts of France, and consequently
contiguous to the British Isles, the lampreys have seven spots in
the jaws, resembling the constellation of the plough, evidently the
same as the eyes, which vulgar opinion assigns to the fish[26]. Their
extreme voracity was such, that criminals were thrown among them to
be devoured. Seneca relates, that Vedius Pollio, a Roman knight,
ordered his servant, who had broken a crystal vase, to be thrown into
a large pond of lampreys[27]; and Columella writes, that they were
sometimes seized with a rabid fury, that resembled canine madness;
in the access of which, they seized upon other fish, so that it was
impossible to keep them in the same pond[28]; and to account for this
extraordinary ferocity, Oppian and others assert, that the lamprey
is impregnated by a serpent; the one issuing from the sea, and the
other rushing down to the rocks, inflamed with madness, to consummate
the impregnation; and adds, that the extraordinary intercourse was
effected by the lamprey seizing the serpent’s head in its [p076]
mouth[29]. This singular copulation was the reason why the Romans,
who were immoderately fond of lampreys, did not wish to eat them,
when impregnated by the supposed serpent. Horace, therefore, makes
Nasidienus, among the blunders of his supper, serve it in that
state[30].
Lampreys were a favourite dish with our own early monarchs. Henry
II. died by eating them to excess. The celebrated Pope also owed his
death to a surfeit of them. Doctor Johnson remarks in his life of the
poet, that he was in the habit of cooking them himself in a silver
saucepan. The Corporation of Oxford still make up a periodical pye
of this fish for the king, in compliance with ancient usage. But
lampreys have lost their rank at corporation feasts, in consequence
of the more delicious and wholesome turtle being introduced into
modern cookery.
I have never noticed lampreys in the Dublin fish-market; and though
they are frequently used in the South of Ireland, I do not know if
they have ever been made an article of food in Dublin, or the north,
where they are rarely met with.
C.
FOOTNOTES:
[25] Petromyzon, _a_ πετρον, saxum, and μυζαω, sugere.
[26] In Gallia septentrionale murænis omnibus dextra in maxilla
septenæ maculæ ad formam septentrionis aureo colore fulgent. PLIN.
_Hist. Nat._ lib. ix. cap. 39.
[27] Fregerat unus ex servis crystallinum ejus; rapi eum Vedius
jussit, nec vulgari quadam morte periturum, murænis objici jubebatur
quas ingens piscina continebat.—SENECA _de Irâ_, lib. ii. cap. 40.
[28] Commisceri eas cum alterius notæ piscibus non placet, quasi
rabie vexantur quod huic generi velut canino solet accidere. Sævitia
persequuntur squamosos plurimosque mandendo consumunt. COLUMELLA _de
Re Rusticâ_, lib. ix. cap. 17.
[29] Αμφι δε μυραινης φατις ερχεται ουκ αιδηλον
Ὥς μεν γαμει τε και εξ ἅλος ερχεται αυτη
Προφρων ἱμειουσα παρ’ ιμειροντι γαμοιο
Ητοι ὁ μέν φλογεῃ τεθοωμενος ενδοθι λυσσῃ
Μαινεται ἔις φιλοτητα και ἔγγυθι συρεται ἅκτης
Πικρος ὄφις. κ.τ.λ.—OPPIAN, _Halieut._ lib. i. V. 554.
[30] Adfertur squillas inter muræna natantes, In patinâ porrecta:
“hæc gravida,” inquit, “Capta est.”—HOR. lib. ii. Sat. 8. lin. 46.
_Observations upon the Motion of the Leaves of the Mimosa Pudica_.
[To the Editor of the Quarterly Journal of Science.]
Dear Sir,
Towards the latter part of this summer, Mr. Gilbert Burnett and
myself made several experiments with a view to ascertain the nature
of the movements exhibited by the sensitive plant. We afterwards
found that the greater part of the facts which we had observed, had
been previously described by Mr. Lindsay [p077] and Dr. Dutrochet.
Mr. Lindsay’s observations are to be met with in a MS. preserved in
the library of the Royal Society, which is dated July 1790: this
essay is alluded to by Dr. Smith in his “Introduction to Botany.”
Dr. Dutrochet’s experiments were published in his “Recherches
anatomiques et physiologiques sur la Structure intime des Animaux
et des Végétaux,” which appeared in 1824. With the latter author
the reputation of originality is likely to rest: not undeservedly,
indeed, as there is no reason to suppose that _his_ experiments
were suggested by a knowledge of those performed by Lindsay. It
is, however, an act of literary justice to secure to Mr. Lindsay
the credit of undoubted priority in describing the phenomena which
he noticed in common with Dutrochet. I have drawn up the following
remarks partly for this purpose—partly to have an opportunity of
mentioning some circumstances which escaped the observation of both
experimentalists.
The leaves of the Mimosa Pudica consist either of one or two or
three pairs of leaflets, and occasionally terminate by an odd
one. Each leaflet bears from twenty to sixty subleaflets, which
are disposed in pairs. The petiole or stalk of each leaf, at the
extremity which is attached to the branch or stem of the peant,
swells into an intumescence varying from three to five in length. A
similar intumescence, of proportionate dimensions, is seen upon each
subpetiole, where it is articulated with the petiole, and upon the
base of the stalk of each subleaflet: the intumescence is the part in
which motion takes place.
During the day-time the petioles are observed to have a direction
upwards, or rather to form an acute angle with the upper part of
the stem or branch, to which they are attached: the subpetioles are
divergent: the subleaflets are spread out, so as to lie nearly in one
plane. (_Fig._ 1.)
During the night the petioles are found to be depressed; the
subpetioles to be drawn together, the subleaflets folded, the upper
or solar surfaces of each pair being brought into contact. (_Fig._ 2.)
The leaves rise, the leaflets diverge, and open by throwing down
their subleaflets, at daybreak: the opposite changes occur about
sunset. The experiments that are to be described, are supposed to be
performed in the day-time. [p078]
[Illustration: _Fig._ 1.]
If a terminal subleaflet be pinched with forceps, or cut with
scissors, it rises, together with its fellow; then the next pair
rise; then the next; and so on in succession, till all the pairs of
subleaflets upon the same subpetiole are folded. In a little time
afterwards, the petiole is bent downwards at its intumescence; and in
a few seconds more the remaining leaflets upon the same petiole fold
their subleaflets in pairs, from the base towards the point of the
leaflet.
[Illustration: _Fig._ 2.]
If a subleaflet be burnt, instead of being cut or pinched, the
phenomena above described occur more rapidly: and after they have
taken place, the adjoining leaves upon the same branch are bent down
in succession, their leaflets brought together, and their subleaflets
folded. If the plant be very vigorous and lively, an impression
[p079] made upon one leaf affects the rest in succession. It is well
known that the stem, branches, flowers, and roots of the sensitive
plant have no motion. But M. Desfontaines observed that, on touching
the roots with sulphuric acid, the leaves become folded; and M.
Dutrochet obtained a similar result on burning either the flower or
the stem.
[Illustration: _Fig._ 3.]
[Illustration: _Fig._ 4.]
[Illustration: _Fig._ 5.]
If the plant be shaken, all the leaves are simultaneously thrown
down, and their leaflets folded. Mr. Lindsay attempted to elucidate
the action of the intumescence in raising and depressing the petiole,
in the following manner. He cut out a portion from the upper or solar
surface of the intumescence; after which he found that the petiole,
upon recovering, rose higher than before, (_Fig._ 3.) From another
leaf he removed the inferior portion of the intumescence: he found,
upon _this_ injury, that the leaf declined more than before, and
did not again rise, (_Fig._ 4.) He noticed that a thin slice, pared
from either surface of the intumescence, has a like effect, but in
a less degree than a deep excision: and he found that when similar
experiments are made upon the intumescence of the subpetiole, there
is no essential difference in the result.
Thus Mr. Lindsay discovered, that the force which raises the petiole
exists in the lower part of the intumescence, and that which
depresses it, in the upper. He seems to have considered that the
temporary excess of force in either part is produced by an impulsion
of the sap from the vessels of the yielding portion into those of the
opposite portion. [p080]
Dr. Dutrochet viewed these phenomena in some respects more justly. He
remarked, in addition to what Lindsay had observed, that if, instead
of the upper and under surface, the lateral part of the intumescence
be removed, the petiole becomes not raised or deflected, but inclined
towards the side on which it is injured (_Fig._ 5); and that if
longitudinal slices of the upper, or under, or lateral portions
of the intumescence are immersed in water, these separate slices
immediately become incurvated, that edge being concave which looks
towards the axis of the intumescence. From these facts Dutrochet
inferred that the texture of the intumescence possesses some
modification of irritability; that, when excited, each length of the
intumescence (to use a very imperfect expression) forcibly assumes
an incurvated figure, like a curved spring returning from a state of
temporary extension; that the petiole is raised, when the action of
the lower part of the intumescence predominates; is depressed, when
the upper portion acts with increased energy.
Mr. Burnett and myself had arrived at very similar conclusions
respecting the agency of the intumescence, before we became
acquainted with the inquiries of Lindsay and Dutrochet.
In Dutrochet’s able researches, a more exact analysis, however,
was obtained of the functions of this part. He discovered that the
cortex of the intumescence is the seat of its irritability: for upon
wholly removing the bark, so as to expose the ligneous substance, the
petiole was found to have been rendered motionless. Nevertheless,
the intumescence, thus mutilated, remains capable of transmitting an
impression made upon its leaflets to the leaves adjoining, Dutrochet
further ascertained, that the ligneous substance alone is fitted to
convey the peculiar stimulus, which spreads, from a point of the
plant that has been irritated, to the adjoining leaves.
The experiments already mentioned appear to explain the mode in which
the elevation and depression of the petiole, and the divergence
and approximation of the subpetioles are produced. It is probable
that the contrivance for folding and expanding the subleaflets is
of a similar nature. Mr. Burnett and myself conjectured that each
subleaflet is raised by the under part of the intumescence that
exists at its base, and [p081] depressed by some action of the upper
portion of the same intumescence. In trying the soundness of this
hypothesis, we met with the following evidence in its favour:—
Mr. Lindsay had observed, that at the moment when the petiole is
depressed, the under part of its intumescence assumes a deeper
colour. But the under part of the intumescence of the petiole is
the portion which is shortened during its depression, and which is
overcome on this occasion by the superior force of the upper portion.
Now it is to be remarked that in the subleaflets the upper part
of the little intumescence belonging to each corresponds, in one
respect alluded to, with the lower portion of the intumescence of
the petiole; _it is the portion shortened when the leaf is folded_.
And we found, upon examination, that it likewise distinctly changes
colour at the moment when the subleaflet rises, while the under
surface of the intumescence of the subleaflet does not change its hue.
In pursuing this inquiry, another point of correspondence between
the mechanism which depresses the petiole, and that which raises the
subleaflets, was stated, which has yet additional interest.
[Illustration: _Fig._ 6.]
[Illustration: _Fig._ 7.]
[Illustration: _Fig._ 8.]
When the plant is not in its most lively state, the under surface of
the intumescence of the subleaflet (_b_, _Fig._ 2,) and the upper
surface of the intumescence of the petiole (_a_, _Fig._ 6,) may be
pricked with a needle, without producing action. But if the opposite
surfaces, those namely, which change colour and are shortened when
the petiole is depressed and the subleaflets folded, are touched
with the point of the needle these actions are instantaneously
produced. Here the [p082] subleaflet is most delicately sensible;
_a slight touch_ with the point of a needle upon the upper surface
of the intumescence of the subleaflet (_c_, _Fig._ 1,) causes the
single subleaflet so stimulated to rise; and in this manner all the
subleaflets upon one side of a leaflet may be raised, their fellows
remaining expanded: if the touch be something sharper, the fellow
subleaflet rises at the same time; if ruder still, the next pair of
leaflets fold directly afterwards, and the irritation then proceeds
entirely through the leaflet. But the most satisfactory and curious
results are obtained on stimulating the extension surface of the
intumescence of the petiole. The needle may be applied to every point
upon the upper or solar half of the intumescence of the petiole
(_a_, _Fig._ 6,) without producing any visible effect; but if the
irritation be applied upon the under half, (_d_, _Fig._ 6,) either
quite below or laterally, the petiole is immediately depressed. The
transition is abrupt from the surface against which the needle may be
made to prick, without exciting action, to one which, when the needle
reaches it, causes the petiole to be instantaneously thrown down.
It appears, therefore, that each intumescence has a surface
especially adapted to receive mechanical impressions; which surface
is placed on the side of the intumescence opposite to that, by which
the consequent motion is produced. A curious but vague analogy may be
traced between these surfaces of the sensitive plant and the organs
of sense in animals.
We painted with a thick layer of lamp-black in oil the intumescence
of different petioles in different ways; the upper surface of one,
the under surface of another, the side of a third. The experiment was
followed by no sensible effect. After a few minutes the petioles,
which had been thrown down by the operation, rose again in each case,
and fell again as readily as before upon being stimulated afresh.
We tried what result would ensue upon slitting the intumescence of
the petiole horizontally. The petiole, after this injury, did not
recover its usual direction; the intumescence appeared to have wholly
lost its properties; the leaf seemed to depress the petiole by its
weight alone, yet the leaflets expanded, and exhibited their usual
irritability, upon the depending stalk. The same effect, however, was
observed, when the [p083] intumescence was divided by a longitudinal
incision, made vertically instead of horizontally.
I have already mentioned that Dutrochet discovered that the ligneous
fibre is the channel, along which an impression is conveyed from
one part to another. Mr. Burnett and myself had made one or two
experiments upon the course which the irritation follows when
spreading from leaflet to leaflet, where several are placed upon the
same petiole.
If the upper third of a petiole bearing four leaflets be divided
longitudinally, the irritability of the leaflets remains for many
days unimpaired; upon cutting with scissors one subleaflet after the
plant has recovered itself, the irritation is observed to descend
the wounded leaflet, and then to pass to that adjoining upon the
same side of the petiole: afterwards the petiole falls, but there
the effect stops; it does not extend to the two other leaflets;
the direct route is cut through, and the irritation seems to find
no circuitous way, as might have been expected, perhaps through
the intumescence of the petiole back again to the leaflets, on its
summit. If on a petiole, bearing four leaflets, a lateral incision be
made, cutting the petiole half through it at a point between the two
leaflets which are situated on one side, upon irritating either of
the leaflets, between which the incision has been made, it folds its
subleaflets; then the two opposite leaflets fold _their_ subleaflets;
and _last of all_, the leaflet next adjoining that first irritated,
but isolated from it by the incision, becomes folded.
In the few remarks which I have thus put together, I have quoted
Lindsay and Dutrochet only as far as their researches anticipated
my own: I leave unnoticed many experiments, in several of which
these authors are again found to have accidentally coincided. The
experiments to which I allude do not, however, serve to illustrate
the nature of the motion exhibited by the sensitive plant, to the
examination of which subject alone my attention was, in the present
instance, directed, in the expectation that it might throw light upon
the obscure and interesting subject of muscular action.
I remain, my dear Sir, Your’s truly,
HERBERT MAYO.
19, _George Street, Hanover Square_,
_August 29, 1827_.
[p084]
_Experiments on the Nature of Labarraque’s disinfecting Soda
Liquid_. By M. Faraday, F.R.S., Corr. Mem. R. Acad. Sciences, Paris,
&c. &c.
1. The following experimental investigations relate to the nature of
that medicinal preparation which M. Labarraque has lately introduced
to the world, and named _Chloride of oxide of Sodium_. They were
occasioned by the accounts which were given of this and other
substances of similar power, to the members of the Royal Institution,
at two of their Friday evening meetings[31]; the value of the
preparation, the uncertainty of its nature, and the inaccuracy of its
name, all urging the inquiry.
2. In the first instance the inquiry was directed to the nature of
the action exerted by chlorine gas upon a solution of carbonate
of soda, questions having arisen in the minds of many, whether it
was or was not identical with the action exerted by the same gas
on a solution of the caustic alkali, and whether carbonic acid was
evolved during the operation or not. Chlorine gas was therefore
carefully prepared, and after being washed was sent into a solution
of carbonate of soda, in the proportions directed by M. Labarraque;
_i. e._ 2800 grains of crystallized carbonate of soda were dissolved
in 1.28 pints of water; and being put into a Woulfe’s apparatus,
two-thirds of the chlorine evolved from a mixture of 967 grains
of salt with 750 grains of oxide of manganese, when acted upon by
967 grains of oil of vitriol, previously diluted with 750 grains
of water, were passed into it; the remaining third being partly
dissolved in the washing water, and partly retained in the open space
of the retort and washing vessel. The operation was conducted slowly,
that as little muriatic acid as possible might be carried over into
the alkali. The common air ejected from the bottle containing the
solution was collected and examined; but from the beginning to the
end of the operation not a particle of carbonic acid was disengaged
from the solution, although the chlorine was readily absorbed.
Ultimately a liquid of a very pale [p085] yellow colour was obtained,
being the same as M. Labarraque’s soda liquor, and with which the
investigations were made that will hereafter be described.
3. An experiment was then instituted, in which the effect of excess
of chlorine, upon a solution of carbonate of soda of the same
strength as the former, was rendered evident. The solution was put
into two Woulfe’s bottles, the chlorine well washed and passed
through, until ultimately it bubbled through both portions without
absorption of any appreciable quantity. As soon as the common air
was expelled, the absorption of the chlorine was so complete in the
first bottle, that no air or gas of any kind passed into the second,
a proof that carbonic acid was not liberated in that stage of the
experiment. Continuing the introduction of the chlorine, the solution
in the first bottle gradually became yellow, the gas not being yet
visible by its colour in the atmosphere above the solution, although
chlorine could be detected there by litmus paper. Up to this time no
carbonic acid gas had been evolved; but the first alkaline solution
soon acquired a brighter colour, and now carbonic acid gas began
to separate from all parts of it, and passing over into the second
bottle, carried a little chlorine with it. The soda solution in the
first bottle still continued to absorb chlorine, whilst the evolution
of carbonic acid increased, and the colour became heightened.
After some time the evolution of carbonic acid diminished, smaller
quantities of the chlorine were absorbed by the solution, and the
rest passing into the atmosphere in the bottle, went from thence
into the second vessel, and there caused the same series of changes
and actions that had occurred in the first. The solution in the
first bottle was now of a bright chlorine yellow colour, and the gas
bubbled up through it as it would through saturated water.
4. When the chlorine had saturated the soda solution in the second
bottle, and an excess of gas sufficient to fill several large
jars had been passed through the whole apparatus, the latter was
dismounted, the solutions put into bottles and distinguished as
the saturated solutions of carbonated soda; they were of a bright
greenish-yellow colour, and had an insupportable odour of chlorine.
5. The saturated solution (4) was then examined as to the [p086]
change which had been occasioned by the action of the chlorine. It
bleached powerfully, and apparently contained no carbonated alkali:
but when a glass rod was dipped into it and dried in a warm current
of air, the saline matter left, when applied to moistened turmeric
paper, reddened it considerably at first, and then bleached it; and
this piece of paper being dried and afterwards moistened upon the
bleached part, gave indications of alkali to fresh turmeric paper.
6. A portion of the saturated solution (4) being warmed, instantly
evolved chlorine gas, then assumed a dingy appearance, and ultimately
became nearly colourless; after which it had an astringent and saline
taste. Being evaporated to dryness at a very moderate temperature, it
left a saline mass, consisting of much common salt, a considerable
quantity of chlorate of soda, and a trace of carbonate of soda. This
mixture had no bleaching powers. The dingy appearance, assumed in
the first instance, was found to be occasioned by a little manganese
which had passed over into the solutions, notwithstanding the care
taken in evolving and washing the gas.
7. From these experiments it was evident that when chlorine was
passed _in excess_ into a solution of carbonate of soda (3), the
carbonic acid was expelled, and the soda acted upon as if it were
caustic, a mixture of chloride of sodium and chlorate of soda being
produced; with the exception of the small portion of carbonate of
soda which, it appears, may remain for some time in the solution in
contact with the excess of chlorine at common temperatures, without
undergoing this change. The quantities of chloride of sodium and
chlorate of soda were not ascertained, no doubt being entertained
that they were in the well-known proportions which occur when caustic
soda is used.
8. The Labarraque’s soda liquor which had been prepared as described
(2), was now examined relative to the part the chlorine played in
it, or the change the alkali had undergone, and was soon found to
be very different to that which has been described, as indeed the
experiments I had seen made by Mr. Phillips[32] led me to expect. The
solution had but little odour of chlorine, its taste was at first
sharp, saline, scarcely at [p087] all alkaline, but with a persisting
astringent biting effect upon the tongue. When applied to turmeric
paper, it first reddened and then bleached it.
9. A portion of the solution (2) being boiled, gave out no chlorine;
it seemed but little changed by the operation, having the same
peculiar taste, and nearly the same bleaching power as before. This
is a sufficient proof that the chlorine, though in a state ready to
bleach or disinfect, must not be considered as in the ordinary state
of solution, either in water or a saline fluid; for ebullition will
freely carry off the chlorine under the latter circumstances.
10. A portion evaporated on the sandbath rather hastily, gave a dry
saline mass, quite unlike that left by the _saturated solution_
already described (6); and which, when dissolved, had the same
astringent taste as before, and bleached solution of indigo very
powerfully: when compared with an equal portion of the unevaporated
solution, which had been placed in the mean time in the dark, its
bleaching power upon diluted sulphate of indigo was 30, that of the
former being 76. Another portion, evaporated in a still more careful
manner, gave a mass of damp crystals, which, when dissolved, had the
taste, smell, and bleaching power of the original solution, with
almost equal strength.
11. These experiments shewed sufficiently that the whole of the
chlorine had not acted upon the carbonate of soda to produce chloride
of sodium, and chlorate of soda; that much was in a peculiar state of
solution or union which enabled it to withstand ebullition, and yet
to act freely as a bleaching or disinfecting agent; and that probably
little or none had combined with the sodium, or been converted into
chloric acid. To put these ideas to the test, two equal portions of
the Labarraque solution were taken; one was put into a large tube,
closed at one extremity, diluted sulphuric acid was added till in
excess, and then air blown through the mixture by a long small open
tube, proceeding from the mouth, for the purpose of carrying off
the chlorine; the contents of the tube were then heated nearly to
the boiling point, air being continually passed through. In this
way all the chlorine which had combined with the carbonated alkali
without decomposing it, was set free by the sulphuric acid, and
carried off by the current of air and vapour, whilst any which had
acted chemically upon the alkali would, [p088] after the action of
the sulphuric acid, be contained in solution as muriatic and chloric
acids, and from the diluted state of the whole, would not be removed
by the after-process, but remain to be rendered evident by tests. The
other portion being diluted, had sulphuric acid added also in excess,
but no attempt was made to remove the chlorine. Equal quantities of
these two portions in the same state of dilution were then examined
by nitrate of silver for the quantities of chlorine sensible in them,
and it was found that the latter portion, or that which retained the
whole of the chlorine thrown into it, contained above sixty times as
much as the former.
12. Now although it may be supposed that in the former portion that
part of the chlorine, which, in acting energetically, had produced
chloric acid, could not be detected by the nitrate of silver, yet
more than a sixth of the small portion which remains cannot be thus
hidden; and even that quantity is diminished by the sulphuric acid
present in excess, which tends to make the chlorine in the chlorate
sensible to nitrate of silver: so that the experiment shews that
nearly 59 parts out of 60 of the chlorine in M. Labarraque’s liquid
are in a state of weak combination with the carbonated alkali, and
may be separated by acids in its original condition; that this
quantity is probably wholly available in the liquid when used as a
bleaching or disinfecting agent; that little, if any, of the chlorine
forms chloride of sodium and chlorate of soda with the alkali of
the solution; and that the portion of chlorine used in preparing
the substance which is brought into an inactive state, is almost
insensible in quantity.
13. The peculiar nature of this compound or solution, with the
results Mr. Phillips had shewn me (8), obtained by evaporation of a
similar preparation to dryness, induced me to try the effects of slow
evaporation, crystallization, heat, and air upon it. In the first
place five equal portions of the solution prepared by myself were
measured out: two were put into stoppered bottles, two were put into
basins and covered over with bibulous paper, and one was put into a
basin which was left open; all were set aside in an obscure place,
and remained from July 16th to August 28th. Being then examined, the
portions in the basins were found crystallized and dry; the crystals
were large and flat, striated and imperfect, resembling those formed
[p089] in a similar way from carbonate of soda. They were not
small and acicular, were nearly alike in the three basins, and had
effloresced only on a few minute points. A part of one portion, when
dissolved, gave a solution, having an alkaline taste, without any
of the pungency of Labarraque’s liquid; and which, when tested by
turmeric paper, reddened, but did not bleach it.
14. One of these portions that had effloresced least was selected,
and being dissolved, was compared in bleaching power upon diluted
sulphate of indigo, with one of the portions of solution that had
been preserved in bottles. The former had scarcely any visible
effect, though sulphuric acid was added to assist the action; a
single measure of the indigo liquor coloured the solution permanently
blue, whereas seventy-seven such measures were bleached by the
portion from the bottle. Hence the process of slow crystallization
had either almost entirely expelled the chlorine, or else had caused
it to react upon the alkali, and by entering into strong chemical
combination as chloride and chlorate, had rendered it inert as a
bleaching or disinfecting agent.
15. From the appearance of the crystals there was no reason to expect
the latter effect; but to put the question to the proof, one of the
evaporated portions, and one of the fluid portions contained in the
bottles, were acted upon by sulphuric acid, heat, and a current of
air, in the manner already described (11), to separate the chlorine
that had not combined as chloride or chlorate. They were then
compared with an equal portion of the solution, which retained all
its chlorine, nitrate of silver being used as before: the quantity of
chloride indicated for the latter portion was 60 parts; whilst that
of the fluid portion deprived of as much free chlorine as could be,
by sulphuric acid and blowing, was 6 parts; and for the evaporated
and crystallized portion, similarly cleared of free chlorine, only
1.5 parts.
16. This result, as compared with the former experiment of a similar
kind (11), shewed, that though reaction of the chlorine on the
carbonate had taken place in the evaporated portion, it was only to a
very slight extent, since the chlorine was almost as much separated
from it by the process altogether, as it had been from the recent
preparation by sulphuric acid, blowing, and heat. The experiment
shewed also that there [p090] was a gradual reaction of the chlorine
and alkali in the fluid preparation, proceeding to a greater extent
than in the evaporated portion; for chlorine, equal to five parts,
was found by the nitrate of silver to remain. Hence this preparation
is one which deteriorates even in the small space of forty-three
days. Whether the effect will proceed to any great extent, prolonged
experiments only can shew.
17. From an experiment made upon larger quantities of the Labarraque
liquor, it would appear that the force of crystallization alone
is sufficient to exclude the chlorine. A quantity was put into an
evaporating basin, and left covered over with paper from July 16th
to August 28th. Being then examined, a few large crystals were found
covered over with a dense solution; the whole had the innocuous
odour of Labarraque’s fluid, and the fluid the usual acrid, biting
taste. The crystals being separated, one of the largest and most
perfect was chosen, and being well wiped on the exterior, and pressed
between folds of bibulous paper, was rubbed down in water, so as to
make a saturated solution. This had no astringent taste like that of
Labarraque’s fluid, or the mother-liquor, but one purely alkaline;
and when applied to turmeric paper, reddened, but did not bleach it.
Equal portions of this saturated solution and of the mother-liquor
were then compared in bleaching power, acid being added to the former
to assist the effect: it was found, notwithstanding that portions of
mother-liquor must have adhered to the crystal, that its solution had
not 1/21th part the power of the mother-liquor. This, in conjunction
with the other experiments, is a striking instance of the manner
in which the carbonate of soda acts, as a simple substance, with
the chlorine in the solution. The crystal itself had never been in
contact with the air: but whether it should be considered as the
excess of carbonate of soda only which crystallized; or whether it
is essential to the formation of these crystals that chlorine should
simultaneously be given off into the air; or what would take place,
if the water were abstracted without the evolution of chlorine, I
have not determined.
18. Notwithstanding the perfect manner in which the chlorine may be
thus separated by crystallization and slow evaporation to dryness,
yet it is certain that by quick evaporation a [p091] substance
apparently quite dry may be obtained, which yet possesses strong
bleaching power. In one experiment, where, of two equal portions, one
had been evaporated in the course of twenty-four hours to dryness
upon the warm part of a sandbath, when compared with the former, it
had not lost more than one-third of its bleaching power.
19. With the desire of knowing what effect carbonic acid would have
on Labarraque’s fluid, and whether it possessed in a greater or
smaller degree the power of ordinary acids to expel the chlorine,
portions of the solution were put into two Woulfe’s bottles, and
a current of carbonic acid gas passed through them. The gas was
obtained from sulphuric acid and whitening in a soda-water apparatus,
and was well washed in water. The stream of gas brought away small
portions of chlorine with it, but they were not sensible to the
smell, and could only be detected by putting litmus paper into the
current. An immense quantity of gas, equal to nearly 1300 times the
volume of the fluid, was sent through; but yet very little chlorine
was removed, and the bleaching powers of the fluid were but little
diminished, though it no longer appeared alkaline to turmeric paper.
Air was then passed through the solution in large quantity; it also
removed chlorine, but apparently not quite so much as carbonic acid.
20. One other experiment was made upon the degree in which the
carbonate of soda in Labarraque’s liquor resisted decomposition by
the chlorine, even at high temperature. Two equal portions of the
fluid were taken, and one of them boiled rapidly for fifteen minutes;
both were then acted upon by sulphuric acid, blowing, and heat, as
described (11), and the two were then tested by nitrate of silver,
to ascertain the quantity of chlorine remaining: it was nearly
three times as much in the boiled as in the unboiled portion; and
by comparing this with the results before obtained (11), it will be
seen that, after boiling for a quarter of an hour, not more than a
twentieth part of the chlorine had acted upon the alkali, to form
chloride and chlorate.
21. It would seem as if I were unacquainted with Dr. Granville’s
paper upon this subject, published in the last volume of this
Journal, p. 371, were I to close my remarks without taking [p092]
any notice of it. Unfortunately, Dr. Granville has mistaken M.
Labarraque’s direction, and by passing chlorine, to “complete
saturation,” through the carbonate, instead of using the quantities
directed, has failed in obtaining Labarraque’s really curious and
very important liquid; to which, in consequence, not one of his
observations or experiments applies, although the latter are quite
correct in themselves.
_Royal Institution, Sept. 3, 1827_.
FOOTNOTES:
[31] See the last volume of this Journal, pp. 211, 460.
[32] See Vol. I. of this Journal, p. 461; and _Phil. Mag._ N. S., I.
376.
HIEROGLYPHICAL FRAGMENTS; _with some Remarks on_ ENGLISH GRAMMAR.
_In a Letter to the Baron William Von_ HUMBOLDT. By a Correspondent.
My dear Sir,
I am happy to tell you that our prospects of new documents from Egypt
are very rapidly increasing: Mr. Burton has had the good fortune to
discover at length, in a mosque, the triple inscription for which he
has been some years in search; and he has been negotiating with the
Pacha for its removal. From its magnitude and state of preservation,
there is every reason to believe that it will rival the pillar of
Rosetta in its importance, and I sincerely hope that it will tend
to check the wildness of conjecture, which has been rioting without
bounds in the regions of Egyptian literature. Mr. Tattam is printing
a Coptic grammar, and I am preparing an Appendix, which is to contain
the rudiments of an Enchorial Lexicon: I ardently wish that Mr.
Burton’s inscriptions may come to my assistance before I complete
it. I have received nothing from France or from Germany for these
four years past: even what is published seems by some fatality to
have been withheld from me; and the booksellers send no answers to my
commissions. I trust your brother will not forget his kind promise to
think of me at Berlin.
I have to thank him and you for your obliging present of your _Letter
to Abel Remusat on the Genius of the Chinese Language_, which has
greatly interested me: the best return that I can make will be to
give you some remarks which have occurred to me on the language of
hieroglyphics in general, [p093] and on the character of the English
language, which seems to approach, in its simplicity, as you have
yourself observed, to the natural structure of the oldest languages,
immediately related to the hieroglyphical form of representation. I
fear, however, that I must apologize to you for the want of method
with which I shall be obliged at present to throw my fragments
together: but it may be allowable to make some difference between a
letter and a finished essay.
Hieroglyphics, in their primitive form, are scarcely to be considered
in any case as simply a mode of expressing an oral language: they
may be a direct and independent representation of our thoughts, that
is, of recollections, or sentiments, or intentions, collateral to
the representation of the same thoughts by the language of sounds.
We find, in many of the Egyptian monuments, a double expression
of the same sense: first, a simple picture, for instance, of a
votary presenting a vase to a sitting deity; each characterized by
some peculiarity of form, and each distinguished also by a name
written over him; and this may be called a pure hieroglyphical
representation, though it scarcely amounts to a language, any more
than the look of love is a language of a lover. But we universally
find that the tablet is accompanied by a greater variety of
characters which certainly do constitute a language, although we know
little or nothing of the sounds of that language; but its import is,
that “such a king offers a vase to the deity;” and on the other side,
that “the deity grants to the king health and strength, and beauty
and riches, and dominion and power.” It is common to see, in these
inscriptions, a number of characters introduced, which are evidently
identical with some of those in the tablets: and however some of
them may occasionally have been employed phonetically, there can
be no question of the nature of the changes which their employment
must have gone through before they assumed the character of sounds:
but this is altogether a separate consideration, and foreign to the
present purpose.
Now it is obvious that objects, delineated with the intention of
representing the originals to the eye by their form, must necessarily
be nouns substantive; and that the picture, containing no verb
whatever, can scarcely be said to constitute [p094] either a positive
or a negative assertion. At the same time, it must be allowed that
a picture of King George the Fourth’s coronation, with the date 19
July 1821, could scarcely be considered otherwise than as asserting
a historical truth; and if any emblem of Truth were attached to it,
or if it were deposited among the records of other historical facts,
it would be equivalent to the expression, “George IV. crowned in July
1821,” which _scarcely_ wants the verb _was_ to convert it into a
positive assertion of a fact.
Strictly speaking, however, there seems to be no direct mode of
supplying the want of the verb _is_ or _was_ in pure hieroglyphical
writing; and if any such sign was employed in the Egyptian or the
old Chinese hieroglyphics, its introduction must have been arbitrary
or conventional; like the employment of a postulate in mathematics.
Every other part of a language appears capable of being reduced,
with more or less circumlocution, to the form of a noun substantive;
and the English language appears to approach to the Chinese in the
facility with which all the forms of grammar may be shaken off.
There is, however, often occasion, in such cases, for a certain
degree of metaphor approaching to poetical latitude; and hence it
may happen that the least literary nations are sometimes the most
poetical. It is, in fact, impossible to exclude metaphor altogether
from the most prosaic language; and it is frequently difficult to say
where metaphor ends and strict logical prose begins; but by degrees
the metaphor drops, and the simple figurative sense is retained. Thus
we may say _liquid ruby_ with the same exact meaning as _crimson
wine_; and yet _ruby_ would never be called an adjective, though
employed merely to express the colour: in _coral lips_, however, the
_coral_, first used metaphorically, is converted by habit into an
adjective, and the expression is considered as synonymous with _labri
corallini_.
The general custom in English is to place the figurative substantive,
used as an adjective by comparison, or by abstraction, before the
name which retains its proper sense: thus a chestnut horse is a
chestnut like or chestnut coloured horse; a horse chestnut is a
coarse kind of chestnut: and in this manner we are enabled to
use almost every English noun substantive as an adjective, by an
ellipsis of the word _like_, which, [p095] if inserted entire or
abridged, would make a real adjective of the word, as war_like_,
friend_ly_. But this omission of the termination, like other figures
of speech, is easily forgotten in the ordinary forms of language;
and the Germans, as well as the English, make use of almost all
their substantives in the place of adjectives, though they are
more in the habit of continuing them into single long words. When,
however, the substantives are so used, they generally become by
abstraction real adjectives: for we seldom think of a _chestnut_,
in speaking of the colour of a horse; but the idea of a light brown
coat, with an ugly pale-red mane and tail, and a fidgety temper, is
very likely to occur to us: and in a horse chestnut the idea of a
horse is out of the question; we only think of a coarse fruit which
a man cannot eat: so that the true sense, in both these instances,
is that of a quality; but _coral lips_ and _ivory hands_ are rather
elliptical expressions, composed of two substantives, which might
fairly be represented hieroglyphically by the assistance of a branch
of coral and an elephant’s tusk. But to describe an abstract quality
by any hieroglyphic character, representative of form only, would
be generally impossible: colours might be imitated, if we supposed
coloured figures to be employed; but other simple ideas, such as
those of sound or touch, could never be immediately presented to the
eye; and some circuitous invention would always be required for their
representation.
Horne Tooke has shewn, with considerable felicity of illustration,
that all the parts of speech may be resolved into the noun and the
verb; but he has not pointed out so clearly that every verb may
be resolved into a noun and the single primitive verb is or was,
which, in this sense, may be said to be the only essential verb in
any language; as we find, indeed, in the Coptic, that almost every
noun becomes a verb, either by the addition of PE, or sometimes even
without it. Thus, _the morning_ BLUSHES is synonymous with _the
morning_ IS _red_; _he loves justice_, with _he_ IS _a lover of
justice_; and _I_ AM _an Englishman_, with _the person now speaking_
IS _an Englishman_. But this must be understood of is, was, or will
be, in all its tenses; the idea of time, if expressed, being an
essential part of the verbal sense.
I confess that some of these reflections have occurred to me in
looking over a very singular work, which I had the curiosity [p096]
to take up, in order to see what kind of information could be
possessed by a person notoriously and professedly ignorant of the
origin and relations of the language which he attempts to teach;
and, in short, what kind of light could be diffused by an apostle
of darkness. Blunders, and some of them ridiculous enough, must, of
course, be found in the works of such a person, but most of them are
such as every schoolboy might correct; and there really is so much of
sagacity in some of Mr. Cobbett’s remarks on the errors of others,
that they well deserve the attention of such as are ambitious to
write or speak with perfect accuracy.
I shall not attempt to enter into a regular criticism of this
_Grammar_; I shall merely make a few miscellaneous observations, as
they have occurred to me in reading it, several of which would be
equally applicable to the best of the existing works of a similar
nature.
In Letter III we are told that _long_ and _short_, though adjectives,
do not express _qualities_, but merely dimension or duration; from a
singular misconception of the proper sense of the word _quality_. We
find, in Letter IV, the rule given by most grammarians, though not by
all, that the article A becomes AN, when it is followed by any word
beginning with a vowel; but it is surely more natural to follow the
sound than the spelling, and, as we should never think of saying an
_youthful_ bride, it seems equally incorrect to say an _useful_ piece
of furniture; for the initial sound is precisely the same. In the
same manner A _unit_ and A _European_, seems to sound more agreeable
than AN; and the best speakers appear to adopt this custom.
Letter VIII gives us a rule for doubling the last letter of a verb in
the participle if an accent is on the last syllable: but it should
be observed that the L is doubled, whether accented or not, as in
_caballing_, _travelled_, _levelled_, _cavilled_, _controlled_. The
same letter contains a “List of verbs, which, by some persons, are
erroneously deemed irregular,” and which have been so deemed from the
time of our German and Saxon ancestors, though Mr. Cobbett thinks
it would be more philosophical to conjugate them regularly. Thus
we may see at once that _freeze_ may as well give us _frozen_, as
_frieren_ gives the Germans _gefroren_; that _hang_ may make _hung_
or _hanged_, according [p097] to its sense, as in German we have
_hienge_ from _hangen_, and _hängte_ from _hängen_, to execute. For
_sling_ and _slung_, we have authority in _schlingen_, _geschlungen_,
for _spring_ and _sprung_ in _springen_ and _gesprungen_; for
_swollen_, _swam_ or _swum_, and _swung_, in _geschwollen_,
_geschwommen_, and _geschwungen_. And it is quite clear from these
examples that “the bad practice of abbreviating, or shortening,” has
nothing to do with the matter.
In Letter XIV we have a very distinct examination of a rule in
punctuation which has been commonly adopted by good printers, without
so distinct a description of its foundation. “Commas are made use of
when phrases, that is to say ‘portions’ of words, are ‘throw_ed_’
into a sentence, and which are not absolutely necessary to assist in
its grammatical construction.” In a word, two commas are very nearly
equivalent to the old fashioned parenthesis. Again, “the apostrophe
ought to be called the mark not of elision, but of _laziness_ and
_vulgarity_;” a remark made in truly classical taste, which might
have been extended with perfect propriety to the subject of the
next paragraph, the _Hyphen_, the insertion of which is, to make it
uncertain whether the words united by it are one word or two. He
goes on admirably in the next page. “_Notes_, like parentheses, are
_interrupters_, and much more troublesome interrupters, because they
generally tell a much longer story. The employing of them arises,
in almost all cases, from confusion in the mind of the writer. He
finds the matter _too much for him_. He has not the talent to work
it all up into one lucid whole; and, therefore, he puts part of it
into _Notes_” . . . . . “Instead of the word _and_, you often see
people put _&_. For what reason I should like to know. But to this
_&_ is sometimes added a _c_; thus, _&c._ _And_ is, in Latin, _et_,
and _c_ is the first letter of the Latin word _caetera_, which means
the like, or _so on_. This abbreviation of a foreign word is a most
convenient thing for such writers as have too much indolence or
too little sense to say fully and clearly what they ought to say.
If you _mean_ to say _and the like_, or, _and so on_, why not say
it? . . . The abbreviation is very frequently made use of _without
the writer having_ any idea of its import.” But it is surely a
mischievous maxim, never to “think of _mending_ what you write. Let
it _go_. No [p098] patching; no _after painting_.” On the other
hand he is right in protesting “against the use of what, by some,
is called the _dash_. Who is to know what is intended by the use of
these _dashes_? . . . . It is a cover for ignorance as to the use of
points; and it can answer no other purpose.”
In Letter XV, there is a singular conceit with regard to the keeping
up a distinction between _a_ and _an_, where it is insisted that we
must not say “_a_ dog, cat, owl, and sparrow,” because owl requires
_an_; “and that it should be, a dog, a cat, an owl, and a sparrow;”
which is certainly better, and would be so, even if there were no owl
in the question.
Letter XVII. The criticism on Milton’s “than _whom_ none higher sat,”
is perfectly correct. _Than_ is never a preposition, and is simply a
variation from the older _then_, both in English and in German. _John
is better than James_ means simply John is good first, then James:
_er_ is _eher_ or _e’er_. _Who_ would sound awkwardly, but would be
more grammatical.
Letter XIX gives a definition of the ellipsis, which would be a
lesson to Apollonius himself: the compasses, it seems, “do not take
their sweep all round, but leave out parts of the area or surface.”
The objection to Blackstone’s language is very questionable. “The
very _scheme and model_ WAS settled,” may, perhaps, be defended,
because scheme and model are considered as one thing, the words being
intended to illustrate each other, but not to point out different
attributes of the administration of justice; and both words may
be admitted, as a collective term, to govern a singular rather
than a plural verb. It seems also to be an error to make _with_ a
conjunction rather than a preposition, and to say “The bag, with the
guineas and dollars in it _were_ stolen,” or “zeal, with discretion,
_do_ much.” “I expected to have seen,” is justly noticed as a common
error for “I expected to see.” The meaning of an _active_ verb is
erroneously confounded with that of a _transitive_ verb, in the
remarks on the word _elope_, which means to go off, or to run off,
and we should naturally say _was_ gone off, but _had_ run off.
The nature of the subjunctive mood is dismissed in the same Letter
without better success than has been obtained by former grammarians.
An essay was published about thirty years ago in a periodical work,
which brings the subject into a small compass; [p099] suggesting that
the subjunctive mood ought always to be considered as a _conditional
future_. The examples given are, “If the Elbe _is now_ open, we shall
soon have the mails, and _then_, if there _be_ any news from the
army, I will send it you immediately.” “If Catiline _was_ generous,
it was in order to serve his ambition.” The subjunctive past, if I
_were_, becomes present, by being the future of the past; going back
to the time when the present was future, and therefore contingent;
and this conditional sense involves no difficulty, except when a
mistaken adherence to the fancied rules of grammar forces it in where
it has no business: thus the rules of some grammarians would lead
us to say, if Catiline _were_ ambitious; which is totally contrary
to the true sense of the subjunctive. Mr. Cobbett seems to have
some such distinctions in view when he says that “_if_ has nothing
at all to do with the government of the verb. It is the sense which
governs.” By this he means that _if_ does not require a subjunctive
unless is relates to a _future contingency_. He is right in saying
“Though her chastity _is_ becoming, it gives her no claim to praise”:
but most decidedly wrong in adding “she would be criminal if she
_was_ not chaste”; for _was_ is here used as relating to the present
circumstances, which are the future of the past, and therefore
require the subjunctive _were_ to denote the condition intended. He
has, however, done signal justice to the cause of this injured verb,
by introducing it for _was_, in his sixth lesson, where he says it
should have been “Your Lordship _were_ apprized of every important
circumstance.”
Such errors as this, however, are easily corrected, and many of
the acute remarks which have been here copied are well worthy the
attention of practical grammarians; at the same time enough has been
said, without any disparagement of Cobbett’s talents, to show that
a man cannot be well qualified to teach that which he has not had
the means of properly learning. For although the English language
appears at first sight to be extremely simple and philosophical
in its structure, it has, in fact, been derived from a variety of
heterogeneous sources; it has undergone a variety of vicissitudes,
and has served for the expression of a multiplicity of discussions
on the most refined subjects in literature and history and science,
for [p100] the feelings of oratory, and the passions of poetry, and
it has been worn away by degrees, as the crystal in the stream is
worn to a pebble, till it has returned to a simplicity which wears
the aspect of the immediate offspring of the Chinese or Egyptian or
Mexican Hieroglyphics. But with all this, it has still some spots,
some idioms, which invariable custom obliges us to retain; and
which can only be distinguished from corruptions and vulgarisms by
tracing their history through the different stages of its progress,
including, of necessity, the corresponding idioms in the parent
languages out of which it has arisen.
Believe me always, my dear Sir, Your’s very sincerely, * * * *
_Malaria: an Essay on the Production and Propagation of this Poison,
and of the Nature and Localities of the Places by which it is
produced, with an Enumeration of the Diseases caused by it, and of
the Means of diminishing and preventing them, both at Home and in
the Naval and Military Service_. By J. Mac Culloch, M.D., F.R.S.,
&c. &c. Longman and Co. 1827.
Though we have given a place in our Journal to two articles on
Malaria from Dr. Mac Culloch, we have thought it expedient to take
some notice of his book under the form of a review; particularly
as some matters have come under our cognizance, which may add some
illustrations to this subject where the author appears to have been
in a state of deficient information, or to have shunned the question
for reasons which appear to us somewhat over refined.
We allude principally here to the localities and the facts, as they
are now before us; circumstances and events which seem to us of the
greatest importance, as enforcing the value of the details which he
has collected, and as holding out warnings to the people respecting
the preservation of their healths, in addition to those which the
work before us has given in describing the soils or characters of
ground in England from which this destructive poison is generated.
And before we proceed to the analysis of his book, we shall state
what those are, or at least a few of them, while wondering that he
should have overlooked them, or regretting that any fancies should
have prevented him from stating what would have been of so much
utility. [p101]
It is notorious that, in the last autumn, the remittent fevers in
various parts of the country amounted to a species of pestilence,
such as has scarcely been known in England from this cause, or we
might almost indeed say, from any other disease since the days of
Sydenham. Wherever ague had ever existed, or even been supposed
possible, in those places was this fever found: so that in all the
well-known tracts in Lincolnshire, Norfolk, Suffolk, Kent, Essex,
Sussex, Hampshire, and so forth, there was scarcely a house without
one or more inhabitants under fever, while the event, as might be
suspected, was a considerable mortality. In the parish of Marston,
in Lincolnshire, for example, it amounted to 25 in 300 inhabitants;
in some other places, it reached one in sixteen, one in thirteen,
one in nine. And so extensive was its range, that even Hastings did
not escape; while it should be almost superfluous to say that every
other town on the sea-coast was so much infested by it, that they
who resorted to them for bathing, as usual, found themselves most
awkwardly situated, and also suffered in considerable numbers.
To come nearer home, and to what must interest us of the metropolis
more, the same fevers were extremely abundant in various parts of
the outskirts of London, as also in the villages or towns which are
connected with it, within a range of from six to ten miles. Not
to enumerate all these, this was the case throughout the range of
streets or houses which extends from Buckingham Gate to Chelsea; in
which long line, it is said, that almost every house had a patient
or more under this fever; though, as the author has truly observed,
these were mistaken for typhus, or at least thus misnamed. Thus it
was also about Vauxhall and Lambeth; and to a great extent among
all that scattered mixture of town and country which follows from
Whitechapel, from Bishopsgate, and so forth, and very particularly
along Ratcliffe Highway, and so on, to an indefinite range along
the river, not only on this side but on the opposite one, so as
to include Rotherhithe, and then proceeding onward to Deptford,
Greenwich, Woolwich, Plumstead, so as to carry us beyond the boundary
which we proposed to notice.
And in addition to the towns or villages which we have just named,
we may enumerate Lewisham, in which we knew one house in which there
were nine patients under this fever, which proved mortal to one.
Dulwich, especially subject to this disorder, Fulham, Ealing, and the
several other villages along the Thames, as far as Chertsey; and even
Richmond, [p102] where, as at Lewisham, there was one house known to
us, inasmuch as being intimate friends, where ten individuals at one
time were suffering under this disease.
We must not prolong this enumeration, since we might easily occupy
a dozen of our pages with similar details, ranging, in fact, all
over England; but we must still observe, that whatever was the
pestilence last year, it promises to be much greater in the present
one. This is easily judged from the manner in which the season has
set in; but still more decidedly from the extraordinary prevalence
of ague in the spring; since that which is intermittent fever then,
will be remittent in the autumn, or rather, as the author has
justly remarked, there will scarcely be a definite season of vernal
intermittent, but the remittent will commence immediately, increasing
in extent and severity as the summer advances, and promising to
become, in the autumn, the greatest season of disease that England
has known for this century.
As an example of this, it must suffice to enumerate two or three
facts, while these are as satisfactory for our purpose as a thousand
would be. The most general of these is, that ague is at this moment
extremely abundant where it was formerly so little known as not to
be noticed, and that where single cases used to occur, there are now
hundreds. Thus has it prevailed at Fulham and Ealing, and in the
outskirts of London, and even in the town itself; and thus does it so
prevail at Greenwich, Deptford, and in the associated vicinity, that
a medical friend informs us, that it comprises more than two-thirds
of his entire practice, which is very extensive; whereas a few years
ago he had rarely a patient in a year. Thus also in the Military
Hospital at Woolwich, there were in the spring three hundred patients
with this disease; while in former times, we are assured, that an
ague was scarcely known once in five or six years.
These are a few of the facts within our knowledge, but not one in
a thousand, which evince the necessity of the publication before
us; a book which seems to have been singularly well-timed, in as
far as its purpose is, by a dissection of the sources of malaria,
to diminish the ravages of both these kinds of fevers. And in this
view we consider it a work of very considerable utility, inasmuch as
it points out all the needful circumstances, as to prevention, in
great detail; while these seemed particularly called for in England,
from the entire and not less singular neglect which this subject has
experienced, not only from the people at large, but from the medical
profession. Beyond this, all that we need say of [p103] the character
of the work is, that it contains the only regular and complete
attempt at the natural history of Malaria that has been executed;
since the several foreign writings on this subject are partial, or
imperfect, or local in their investigations; and having said thus
much, we shall proceed to give a brief analysis of its form and
matter. And this analysis may be truly brief, without inconvenience;
since the two Essays from the pen of the author, to which we have
given a place in our Journal, will supersede the necessity of making
that useful and practical abstract which we should otherwise have
felt ourselves bound to give.
To pass over an introductory chapter of the usual necessity, the
author commences by pointing out the several disorders, in a general
way, which are produced by malaria, for the purpose of proving the
sources of this poison; and as we are of those who take the facts as
already proved, we need not notice it further.
The third chapter details the characters of those soils or situations
which are most commonly or generally admitted to produce this poison:
and though it contains some facts not very universally known, we
shall also pass it over as of less moment than that which follows.
This is the fourth chapter, containing the details of the
circumstances producing malaria, which have been either denied or
overlooked; and it is one of the most important practical chapters in
the book, inasmuch as it is to the popular ignorance of these that
we must attribute a large proportion of the cases of fever occurring
in common life. These, therefore, we shall mark briefly; and even
the briefest notice will be of use in the way of precaution, while
we must refer to the book itself for those proofs of the truth of
the several views, which we could not take room to give. Generally,
however, we may state this leading argument of the author, because it
is brief, and, to us, appears satisfactory. It is this: that as the
quantity of the poison which any person can inspire is necessarily
small, and as this small quantity can be produced by a small marshy
spot as well as a large one, it is the same as to the production
of disease, whether the marsh is a foot square or a mile, provided
the exposure be complete: while also, any piece of ground where
vegetables decompose under the action of water, is virtually a marsh,
or must produce malaria.
This enumeration, therefore, under that view, comprises, in addition
to marshes, whether fresh or salt, all the cases where water is
present in such a manner as to act upon vegetables; and the chief are
the following. [p104]
It is shown, and by facts, that the rushy swamps of high moorlands,
however small the extent, do produce this disease; and we must not
here forget to name what, however, belongs to the preceding chapter,
woods and coppices, little suspected in England, yet shown to be
the cause of fevers in Wales, and also in Sussex; very probably,
every where else. It is also shown that meadows and moist pastures,
whether in flat lands or on elevations, generate fevers; and very
particularly, should they have been affected by inundation or unusual
moisture, and if that should be followed by heat. And while it is
also specifically shown how, in all cases, it is the produce of
the drains or ditches required in meadow lands, it is distinctly
proved that, even without these, malaria is produced, or that it is
generated by the meadow or moist pasture itself.
It is also shown that this poison is produced by rivers, by all
flat rivers at least, or those of which the progress is slow and
through meadow lands; while this is pointed out as one of the causes,
especially, which is not suspected or not believed in England. And
here we can add a fact to our author’s statement, which is decisive:
this is the case of the barracks at Morne Bruce, in Dominica,
situated on a steep and rocky hill, perfectly dry, and free from
all other causes of suspicion, while eternally subject to the most
severe fevers. And the cause is, a mountain stream, about 300 yards
below this building, in the valley, always covered by a mist in the
evenings, and ascertained, by direct experience, to be the very cause
of the diseases in question.
Our author also notices canals, mill-ponds, ornamental waters, and
all other pools and ponds, even to so small a dimension as those
formed in gravel-pits; pointing out those, in particular, as common
causes of fever about London, and apparently much inclined to pass
a very severe judgment on the canal in St. James’s Park, and also
on the pond in St. James’s Square, while apparently restrained by
his prudential reasons, which appear to us sufficiently misplaced,
or, as we should fairly call them, somewhat absurd. But as we must
not affront a writer whose papers we have admitted, we shall say no
more on this matter. In noticing drains, he also speaks of moats and
modern fortifications; attempting to show that the fevers so common
in the sieges of ancient castles were produced by their moats, and
noticing the familiar fact of the frequency of fevers in fortified
towns. Lakes also are pointed out as situations generating this
poison: and it is here especially noticed that if, in those and other
cases, malaria is produced by the vegetable growth and decomposition,
[p105] so is it the consequence of the exposure of the mud of such
receptacles of water; a cause which is again treated of at greater
length in the subsequent chapter.
This chapter relates to what the author calls obscure and disputed
cases. We shall pass over these, which, as not implying precautionary
measures, are of the least interest, and commence by noticing the
case of vegetable putrefaction. It is attempted to show, that the
vegetable need not be living to produce malaria, but that, even if
utterly decomposed, its elements, acting on water, can generate this
poison. Among the cases under this head, are flax and hemp ponds,
common sewers and drains, dunghills, and tide harbours; and the
evidences under each are sufficient to make good the assertion. But
the most important of all, in our view at least, is bilge-water:
since our author has pretty clearly shown that all the fevers of
ships (excepting, of course, a few casual instances of contagion)
arise from this cause, and that if ships were kept clean, fever or
sickness would be nearly unknown at sea. This we do indeed conceive
one of the most important points in the work before us; and if the
author has referred to Sir Henry Baynton, as a stranger, we can quote
him, as a friend, that warrants for all that is here asserted, and
for far more; since his collection of facts on this subject is most
important, and we think him almost culpable in not having long ago
given them to the public. If the Leviathan was always the healthiest
ship in the navy; if she even left the West Indies, after a long
anchorage and service, with a crew of 500 men, and not one sick, it
is a case in the navy which never occurred before, nor since, and
which arose entirely from the knowledge of this able and careful
officer respecting the subject that we are discussing.
A sixth chapter explains, under the head of revolutions in the
production of malaria, a variety of circumstances not easily
admitting of abridgment. The chief of these are, the effects produced
by drainages, and reversely, those which arise from inundations or
other incidental causes affecting the state of the soil. But the most
important view which it contains is that which relates to the effect
of embankment in rivers, and to the geological changes produced by
the distribution of alluvia. As, however, we cannot well state this
in a small space, we shall pass to the chapter on the Propagation of
Malaria.
This is the largest, and, as it strikes us, the most interesting
of the whole; while the author has made it the depository of a
variety of remarks and recommendations on this [p106] subject, very
particularly as it relates to the army. If he is correct,—and we
see no reason to doubt it, from the nature of the statements,—the
ignorance of this subject, even among the medical department of the
army, has been most extraordinary and most unaccountable; while if
Walcheren is proof enough of this, the writer before us has pointed
out facts enough to show that it was not a solitary case, while
evidently restrained by fear of some sort—we are almost inclined to
call it cowardice—from telling all that he might have told. And we do
think it wrong to retain or suppress that which is important to the
public safety, under a fear that the feelings of individuals may be
hurt; since the business of a writer is with justice and utility, and
the security or welfare of thousands is of infinitely greater moment
than the comforts of a few, and those also culpable.
Under this head, propagation, the author describes how this poison
is conveyed by the winds, while the facts add much to the number
and variety of the precautionary measures. And here also we find
a speculation of no small curiosity, respecting the East wind,
attempting to prove that wherever this is insalubrious or pernicious,
it arises from its being the vehicle of malaria; while attempting
also to prove that this substance can be conveyed from Holland to
the coasts of England in that wind. We shall not pretend to give an
opinion on this subject; and since the author himself has noticed
it in the paper printed in our present number, we shall suffer our
readers to form their own judgments respecting it.
One also of the most curious facts mentioned in this chapter, is the
singular limitation of malaria; and we must admit that the instance
quoted as to the Chatham road is so remarkable as to be almost
incredible; though, as we find that all the people agree in it, we
cannot pretend to say it is not a fact. Indeed the facts of this
nature, so familiar at Rome, are fully as inexplicable; so that all
we can conclude is, that we are ignorant of the philosophy of this
subject: no very great cause of surprise, unless it were proved that
we could explain every thing else which belongs to meteorology.
In the eighth chapter we have an explanation of the effects of
climate and seasons in the production of malaria; and while we
need not analyse the facts which it contains, we may introduce in
lieu of this, the explanations which its statements afford as to
that recent increase of the diseases of malaria which we noticed
at the commencement of this article. The last few years have been
distinguished for an [p107] uncommon prevalence of East winds, and
to such a degree indeed, that we can find no meteorological records
at all to be compared with the history of these years. And while the
history of the intermittent and remittent, in London at least, from
the time of Morton and Sydenham downwards, shows that all its periods
of such diseases have been periods of East winds, it is not difficult
to see how it acts as to both classes of marsh fever. To London,
in particular, it is the best conductor, propagating the malaria
from all the moist lands to the eastward. To the East coast, if our
author’s theory is valid, it brings the malaria from Holland; and,
moreover, as it forms our hottest summers, it causes our own climate
to approximate more to the southern ones, and thus enables our lands
to produce a greater quantity of malaria than in ordinary summers.
To pass from the eighth chapter, the ninth is a partial sketch of
the geography of malaria; a chapter for which the author apologises,
but which is nevertheless a very interesting collection of facts
on a subject where a volume is, doubtless, a desideratum. And it
would require a volume; while, in spite of our author’s fears, we
can really see no reason why such a statistical account of health
should not be drawn up for England, when the utility of it is
unquestionable. It is true that people cannot abandon their homes
or change their residences, because their lots happen to be cast in
an insalubrious country. But it is not less important to know what
and where these dangers are; because, though the inhabitants may be
compelled to abide, they can still correct much of the evil by the
various modes pointed out, or avoid much of the hazard by resorting
to the obvious precautions. To be ignorant, is to be exposed to the
full evil: to know where it lies, is to know how and where to avoid
it in numerous ways; since it will be found that by far the greater
number of diseases occurring, were not necessary or unavoidable, but
have been the result of ignorance as to the precise fact or spot
which did produce the effect in question. And this we conceive to
be the great use of the book before us; and that if ever it, or a
code of rules founded on it, shall become popular, or form a _vade
mecum_, particularly in the country, the effect will be to reduce
most materially the quantity of disease, and very particularly that
which is by far the most serious, the summer and autumnal fevers.
On this around, we should be glad to see a geography of malaria for
England; and we do hope that it will be undertaken by some person
of sufficient industry, and of more [p108] courage than our author;
while we cannot doubt that whoever attempts it would at least find it
a profitable speculation. With these remarks we must pass over this
chapter, as we could take no statement from it which would serve any
useful purpose; though, as far as it goes, it will form a very useful
guide to travellers on the continent of Europe, or to those who, as
emigrants, are in search of a residence abroad.
The tenth chapter examines the inquiries which have been instituted
into the chemical nature of malaria, leaving the question just where
it was. In fact we, as chemists, do not believe that this science is
yet in possession of the means required for analyses of this delicate
nature; but we see no reason whatever why it should be despaired of,
when chemistry has already, within a very few years, effected things
which seemed far more impracticable and hopeless.
The eleventh and last chapter contains an enumeration of the
diseases produced by malaria, presenting a most formidable list, and
absolutely making us shudder in some of the details which relate to
the worst parts of France and Italy. The representation here given
of the average of life in these districts is particularly striking;
while of the truth of all the facts, we can speak from personal
knowledge. Our author has also noticed the effect of this poison
on animals; showing that it is the cause of the noted epidemics in
cattle, and also of the rot in sheep. If he will look into Livy, he
will find a confirmation, which he appears to have passed by when
quoting that author for epidemic seasons: this being, that in the
same years in which epidemic “pestilences” appeared among the people,
there was also a great mortality among the cattle.
We do not know what his own profession will say of his attempt,
or rather proposal, to prove that the celebrated disease of the
nerves called Tic Douleureux is the produce of malaria and a mode of
intermittent fever; nor how they will receive his proposal to arrange
Sciatica and Rheumatic pains, with many other local diseases, under
this head. But this is not our affair: and as he has promised us two
other volumes, on all the diseases which are produced by malaria,
including these, we must wait with patience; knowing at least that he
is a dealer in facts and not in hypotheses, and expecting, that even
if he should fail to establish his point, he will try to do it, as
he has been used to do in the other sciences which he has attempted,
through the road of facts and evidence. [p109]
_An Account of a new Genus of Plants called_ REEVESIA. By John
Lindley, Esq., F.L.S., &c. &c.
In a collection of dried specimens of plants sent to the
Horticultural Society from China, by Mr. Reeves, are a few branches,
with flowers, of a remarkable genus which is at present undescribed,
but which is of so curious a nature, and of such importance with
reference to the determination of some natural affinities, that I
have thought it deserving immediate record; especially as drawings
of the fruit, which have been subsequently obtained from the same
indefatigable correspondent of the Society, render its history
tolerably complete.
The _branches_ appear to be fragments of an evergreen tree; they are
slender, rounded, and smooth. The _nascent gemmæ_ are covered with
a dense rufous pubescence. The _leaves_ are alternate, becoming,
towards the extremities of the branches, opposite by approximation;
their form is ovate-lanceolate acuminate, and in size they vary
from three inches to nearly six in length; the surface, even of
the youngest, is perfectly smooth on each side; their veins are
inconspicuous, the lowest pair of venæ primariæ being divergent at
an angle of about 40°, while the others spread outwards at an angle
of 55° or 60°; the venæ arcuatæ and externæ are obscurely seen,
but form together a number of rhomboidal spaces, equal in diameter
to nearly one third of each side of the leaf; the proportion borne
by the petiole to the lamina is variable, sometimes equalling
one-fourth of the length of the latter, and not unfrequently being
less than one-sixth of its length: this proportion not depending
upon the station of the leaves; the petiole is smooth, half-round,
and thickened at the extremity, where it unites with the lamina.
_Stipulæ_ are none. The _flowers_ are greenish-white, in terminal
thyrsoid compound racemes; the upper part of the _rachis_, and of
its branches, is slightly protected by stellate pubescence; the
_pedicles_ are closely covered with pubescence of the same nature,
and have one subulate downy deciduous bracteola at the base, and
another towards the apex. The _calyx_ is inferior, campanulate,
tapering a little towards the base, densely clothed with stellate
pubescence, bursting irregularly at the apex into [p110] four or
five ovate teeth, which are somewhat imbricated during æstivation,
but which are separated by the growth of the petals long before
the expansion of the flower; the veins of the calyx are remarkably
reticulated, and when cut, a considerable quantity of mucilaginous
viscid fluid is exuded. The _petals_ are whitish-green, hypogynous,
with a convolute æstivation; their _ungues_ are spatulate, and as
long as the calyx; their _laminæ_ oblong, spreading flat, and then
overlapping each other at the base; at the point of separation of
the unguis and lamina is a small callus, and on each side a notch
upon the margin. The _stamens_ are seated upon a long, filiform,
subclavate, smooth torus; the _filaments_ are consolidated into a
capitate five-toothed cup, nearly closed at the orifice, and on
the outside of this cup are placed the _antheræ_, three to each
tooth; the latter are two-celled, with divaricating cells, which
open longitudinally, and are so entangled with each other that the
whole surface of the cup appears, when the antheræ have burst, to
consist of a single many-celled anthera. The _pollen_ is spherical
and smooth. he _ovarium_ is seated within the cup of stamens, and is
so entirely concealed that it cannot be discovered till some part of
the cup is removed by violence; it is ovate, smooth, and formed of
five inseparable cells, each of which has two ovula placed one above
the other, and attached to their placenta by their inner margin; the
_stigma_ is sessile, with five radiating lobes. From the Chinese
drawing, the half-ripe fruit appears to be fleshy, with five deep
angles, and five cells, without any remains of calyx, and with a
slight appearance of separation between the lobes. The ripe fruit
is an obovate, five-angled, five-celled, five-valved, retuse, woody
capsule, with a loculicidal dehiscence, and no separable axis. The
seeds are attached one to each side of the valves, and are expanded
at their lower end into a wing.
From this description it is obvious that, with the single exception
of the contents of the seed, we are in possession of all that it is
essential to know of the structure of this plant. The next subject of
consideration is its affinity.
The stellate pubescence, the thickening of the petiole at the point
where it expands into the lamina, the station of the stamens upon a
long, filiform torus, the external position of the [p111] antheræ,
and the union of the filaments by threes into a cup surrounding
the ovarium, are all characters that forcibly call to recollection
the genus Sterculia. The calyx, indeed, in that genus is generally
divided much more deeply than in the plant now under consideration,
and the antheræ are usually seated at the base of the ovarium;
but, on the other hand, in Sterculia colorata of Roxburgh, which,
if a distinct genus, (ERYTHROPSIS) as I am inclined to believe; is
nevertheless next of kin to Sterculia, the calyx is of the same
figure and divided in the same degree, and the antheræ are also
combined in a capitate cup inclosing the ovarium. If, however, we
pursue this comparison further we find that, with the characters now
adverted to, the similarity ceases; in Sterculia there are no petals,
the calyx has a valvular not imbricate æstivation, the cells of the
fruit separate into distinct folliculi, and do not combine into a
solid woody capsule, and the seeds are destitute of wings.
The fruit suggests so obviously some affinity with Pterospermum,
that it is next necessary to institute a comparison with that
genus. Stellate pubescence, a calyx divided into five portions,
five hypogynous unguiculate petals, and fifteen fertile stamens
united into a cup, seated on a stipitiform torus, and surrounding
the ovarium, a five-celled ovarium, a woody five-celled capsule,
with a loculicidal dehiscence, no axis, and winged seeds; all these
characters are common to Pterospermum and our plant; but on the
other hand the points in which they differ are of much importance.
The æstivation of Pterospermum is valvate recurved not imbricate;
its calyx is five-parted, not four—five-toothed; its anthers have
parallel not divaricating cells, and are seated upon long distinct
filaments, not sessile, upon the outside of a capituliform cup; and
finally the petioles of the leaves are not connected with the lamina
by a thickened space. The seeds are also winged at the apex, not at
the base, but upon this point it is not my wish to insist.
If the comparison thus instituted with Pterospermum and Sterculia be
attentively considered, we cannot fail to remark that the subject of
these observations is nearly equally related to both; to Pterospermum
in its petals and fruit, to Sterculia in its calyx and stamens.
It must, therefore, be stationed between those two genera, thus
confirming the propriety of M. [p112] Kunth’s combination of the
Sterculiaceæ of Ventenat with the Byttneriaceæ of Mr. Brown; and, in
fact, breaking down every barrier between them.
There are many other points that will suggest themselves to the
Botanist, in which this plant is highly worthy of consideration, but
for the present it will be enough to give the botanical characters
with which it may stand recorded. It is named in honour of John
Reeves, Esq., now resident at Canton, to whom we are indebted for
our knowledge of it, from whose unwearied exertions in the cause of
science the botany of China has received material assistance, and to
whom our gardens are indebted for many of the fairest ornaments they
contain.
REEVESIA.
_Ord. Nat._ BYTTNERIACEÆ; _Sterculiam_ (_Erythropsin_) _inter et
terospermum_.
Calyx campanulatus, 5-dentatus, æstivatione imbricatâ, pube
stellatâ tomentosus, bracteolatus. Petala 5, hypogyna, unguiculata,
æstivatione convoluta, callo inter unguem et laminam. Stamina
in toro longo filiformi insidentia. Antheræ 15, sessiles, in
cyatho capituliformi, apice tantum pervio, obsoletè 5-dentato
connatæ, extrorsæ, biloculares, loculis divaricatis intricatis,
longitudinaliter dehiscentibus. Pollen sphæricum glabrum. Ovarium
sessile, intrà cyathum antheriferum, ovatum, glabrum, 5-angulare,
5-loculare, loculis dispermis. Ovula margini loculorum unum super
alterum affixa, superiore basi concavo in inferiorem incumbente.
Stigma 5-lobum, simplicissimum, sessile. Capsula stipitata, lignosa,
obovata, 5-angularis, 5-locularis, loculicidò 5-valvis, axi nullo.
Semina cuique loculo duo basi alata.——Arbor (Chinæ) foliis alternis
exstipulatis, racemis terminalibus compositis, floribus albis.
1. Reevesia thyrsoidea.
_Habitat_ in China (v. s. sp. in Herb. et iconem in Bibliotheca Soc.
Hort.)
[p113]
ASTRONOMICAL AND NAUTICAL COLLECTIONS.
i. _Elementary View of the_ UNDULATORY _Theory of_ LIGHT. _By_ Mr.
FRESNEL.
[Continued from the last Number.]
I shall not undertake to explain here in detail the reasons and the
calculations which lead to the general formulas that I have employed
to determine the position of the fringes and the intensity of the
inflected rays: but I think it right to give at least a distinct idea
of the principles on which this theory rests, and particularly of the
principle of _interference_, which explains the mutual action of the
rays of light on each other. The name of interference was given by
Dr. YOUNG to the law which he discovered, and of which he has made so
many ingenious applications.
This singular phenomenon, so difficult to be satisfactorily
explained in the system of emanation, is on the contrary so natural
a consequence of the theory of undulation, that it might have been
predicted from a general consideration of the principles of that
theory. Every body must have observed, in throwing stones into a
pond, that, when two groups of waves cross each other on its surface,
there are points at which the water remains immoveable, when the
two systems are nearly of the same magnitude, while there are
other places in which the force of the waves is augmented by their
concurrence. The reason of this is easily understood. The undulatory
motion of the surface of the water consists of vertical motions,
which alternately raise and depress the particles of the fluid. Now,
in consequence of the intersection of the waves, it happens, that
at certain points of their meeting, one of the two waves has an
ascending motion belonging to it, while the other tends at the same
instant to depress the surface of the liquid: consequently, when
the two opposite impulses are equal, it can neither be actuated by
one nor the other, but must remain at rest. On the contrary, at the
points in which the motions agree in their direction, and conspire
with each other, the liquid, urged in the same direction [p114] by
each of the forces, is raised or depressed with a velocity equal
to the sum of the effects of the two separate impulses, or to the
double of either of them taken singly, since they are now supposed
to be equal. Between these points of perfect agreement and complete
opposition, which exhibit, one the total absence of motion, the other
the maximum of oscillation, there are an infinity of intermediate
points, at which the alternate motion takes place with more or less
of energy, accordingly as they approach more or less to the places of
perfect agreement, or of complete opposition of the two systems of
motion which are thus combined, or superinduced on each other.
The waves which are propagated in the interior of an elastic fluid,
though very different in their nature from those of a liquid like
water, produce mechanical effects by their interference, which are
exactly of the same kind, since they consist in alternate oscillatory
motions of the particles of the fluid. In fact, it is sufficient that
these motions should be oscillatory, that is, that the particles
should be carried by them alternately in opposite directions, in
order that the effects of one series of waves may be destroyed by
those of another series of equal intensity; for, provided that the
difference of the route of the two groups of waves [derived from the
same origin] be such, that for each point of the fluid the motions
in one direction, belonging to the first series, correspond to the
motions, belonging to the second, in the opposite direction, they
must perfectly neutralise each other, if their intensity is equal:
and the particles of the fluid must remain in repose. This result
will always hold good, whatever may happen to be the direction of the
oscillatory motion, with regard to that in which the undulations are
propagated; provided that the direction of the oscillatory motion be
the same in the two series to be combined. In the waves which are
formed on the surface of a liquid, for example, the direction of the
oscillation is [principally] vertical, while the waves are propagated
horizontally, and consequently in a direction perpendicular to the
former; in the undulations of sound, on the contrary, the oscillatory
motion is parallel to the direction of the propagation of the sound,
[or rather is [p115] identical with it]; and these undulations, as
well as the waves of water, are subject to the laws of interference.
The undulations formed in the interior of a fluid have here been
mentioned in a general manner: in order to form a distinct idea of
this mode of propagation, it must be remarked, that when the fluid
has the same density and the same elasticity in every direction,
the agitation produced in any point must be propagated on all sides
with the same velocity: for this velocity of propagation, which
must not be confounded with the absolute velocity of the particles,
depends only on the density and elasticity of the fluid. It follows
thence that all the points, agitated at the same instant in a
similar manner, must be found in a spherical surface, having for its
centre the point which is the origin of the agitation: so that these
undulations are spherical, while the waves, which are seen on the
surface of a liquid, are simply circular.
We give the name of _rays_ to the right lines drawn from the centre
of agitation to the different points of this spherical surface; and
these rays are the directions in which the motion is propagated.
This is the meaning of the term _sonorous rays_ in acustics, and of
_luminous rays_ or _rays of light_ in the system which attributes the
phenomena of light to the vibrations of a universal fluid, to which
the name of ether has been given.
The nature of the different elementary motions, of which each
wave is composed, depends on the nature of the different motions
which constitute the primitive agitation. The simplest hypothesis
that can be entertained concerning the formation of the luminous
undulations, is, that the small oscillations of the particles of the
bodies, which produce them, are analogous to those of a pendulum
removed but little from its point of rest; for we must conceive the
particles of bodies, not as immoveably fixed in the positions which
they occupy, but as suspended by forces which form an equilibrium
in all directions. Now, whatever the nature of such forces may
be, as long as the displacement of the particles is but small in
proportion to the extent of their sphere of action, the accelerating
force which tends to restore them to their natural position, and
which thus causes them to oscillate on each side of it, may always,
without sensible error, be considered as proportional [p116] to the
magnitude of that displacement: so that the law of their motion must
be the same as that of the motion of the pendulum, and of all small
oscillations in general. This hypothesis, which is suggested by the
analogy with other natural phenomena, and which is the simplest that
can be formed respecting the vibrations of the luminous particles,
may be considered as experimentally confirmed by the observation,
that the optical properties of light are all independent of any
circumstances which cause the greatest difference in the intensity of
the vibrations: so that the law of their motion must be presumed to
be the same for the greatest as for the smallest.
It follows from this hypothesis respecting the small oscillations,
that the velocity of the vibrating particle at each instant is
proportional to the sine of an arc, representing the time elapsed
from the beginning of the motion, taking the circumference for the
whole time required for the return of the particle to the same point,
that is, the time occupied by two oscillations, the one forwards
and the other backwards. Such is the law according to which I have
calculated the formulas which serve to determine the effect of any
number of systems of waves of which the intensities and the relative
positions are given. These formulas will be found in the Annals of
Chemistry, vol. xi., page 254: [they may be applied with security to
the phenomena there considered, though the perfect accuracy of the
hypothesis in all possible cases may be questioned, upon the grounds
of the microscopical observations on the motions of vibrating chords,
published by Dr. Young in the Philosophical Transactions for 1800.
TR.] Without entering into the details of the calculations, I think
it necessary to show in what manner the nature of the undulation
depends on the kind of motion of the vibrating particles.
Let us suppose, in the fluid, a little solid plane which is removed
from its primitive position, towards which it is urged by a force
proportional to the distance. At the beginning of its motion, the
accelerative force produces in it an infinitely small velocity only;
but its action continuing, the effects become accumulated, and the
velocity of the solid plane goes on continually to increase, until
the moment of its arrival at [p117] the position of equilibrium, in
which it would remain, but for the velocity which it has acquired;
and it is by this velocity only, that it is carried beyond the point
of equilibrium. The same force which tends towards this point,
and which now begins to act in a contrary direction, continually
diminishes the velocity, until it is completely annihilated; and then
the force continuing its action produces a velocity in the contrary
direction, which brings the plane back to its place of equilibrium.
This velocity again is very small at the commencement of the return
of the particle, or plane, and increases by the same degrees as
it had before diminished, until the instant of the arrival of the
particle at the neutral point, which it passes with the velocity
previously acquired: but when it has passed this point, the motion is
diminished more and more by the effect of the force tending towards
it, and its velocity is reduced to nothing when it arrives at the
place of the commencement of the motion. It then recommences, at
similar periods, the series of motions which have been described,
and would continue to oscillate for ever, but for the effect of
the resistance of the surrounding fluid, the inertia of which
continually diminishes the amplitude of its oscillations, and finally
extinguishes them at the end of a longer or shorter time, according
to circumstances. [It must not be inferred from this explanation,
that the particles of a fluid transmitting an undulation have any
tendency to vibrate for ever: on the contrary it has been admitted by
the best writers on the theory of sound, that all the motions which
constitute it, as considered in a fluid, are completely transitory
in their nature, and have no disposition to be repeated after having
been once transmitted to a remoter part of the fluid. TR.]
Let us now consider in what manner the fluid is agitated by these
oscillations of the solid plane. The stratum immediately in contact
with it, being urged by the plane, receives from it at each instant
the velocity of its motion, and communicates it to the neighbouring
stratum, which it forces forwards in its turn, and from which the
motion is communicated successively to the other strata of the
fluid; but this transmission of the motion is not instantaneous,
and it is only at the end of a certain time that it arrives at a
determinate [p118] distance from the centre of agitation. This
time is the shorter, as the fluid is less dense, and more elastic;
that is, composed of particles which possess a greater repulsive
force. This being granted, let us assume, in order to facilitate the
explanation, the moment when the moveable plane is returned to the
initial situation, after having performed two complete oscillations
in opposite directions: at this moment, the nascent velocity, which
it had at first, is transmitted to a stratum of the fluid removed
from the centre of agitation by a distance which we may represent
by _d_. Immediately afterwards, the velocity of the moveable plane,
which has a little augmented, has been communicated to the stratum in
contact with it: “hence _it_ has passed successively through all the
following strata;” and at the moment when the first agitation arrives
at the stratum of which the distance is _d_, the second has arrived
at the stratum immediately before it. Continuing thus to divide, in
our imagination, the duration of the two oscillations of the moveable
plane into an infinity of small intervals of time, and the fluid
comprehended in the length _d_, into an equal number of infinitely
thin strata, it is easy to perceive, by the same reasoning, that
the different velocities of the moveable plane, at each of these
instants, are now distributed among the corresponding strata; and
that thus, for example, the velocity which the plane possessed at the
middle of the first oscillations in the direction of the motion, must
have arrived, at the instant in question, at the distance 3/4 _d_: so
that it is the stratum at this distance which possesses at the moment
the greatest direct velocity; and in the same manner when the plane
arrived at the limit of its first direct oscillation, its velocity
was extinguished, and the same absence of motion will be found at the
distance 1/2 _d_.
It is always supposed, that the oscillations of the plane are so
minute in comparison with the length _d_, that their extent may
be neglected in this calculation: and this hypothesis is actually
consistent with the fact, since there is every reason to suppose
that the excursions of the incandescent particles are very small
in comparison with the extent of an undulation, which, though an
extremely minute space, is still an appreciable quantity, and may be
actually measured. Besides, [p119] even if the amplitude of these
oscillations were not in the first instance so wholly inconsiderable,
it would be sufficient to consider an undulation at a greater
distance from the centre of agitation, in order that their extent
might be diminished in any required proportion.
In the second, or retrograde oscillation, the plane, returning
through the same space, must communicate to the stratum of fluid
in contact with it, and to the rest in succession, a motion in
a direction contrary to that of the first oscillation; for when
the plane recedes, the stratum in contact with it, urged against
the plane by the elasticity or the expansive force of the fluid,
necessarily follows it, and fills up the vacuum which its retrograde
motion tends to produce. For the same reason, the second stratum is
urged against the first, the third against the second, and so forth.
It is thus that the retrograde motion is communicated, step by step,
to the most distant strata: its propagation is effected according to
the same law that governs the direct motion; the only difference is
in the direction of the motions, or, in the language of mathematics,
in the sign of the velocities which are imparted to the molecules
of the fluid. We see then that the different velocities which have
existed in the solid plane, during its second oscillation, must exist
at the moment which we are considering, in the different strata
comprehended in the other half of _d_, but with contrary signs. Thus
the velocity, for example, which the plane had in the middle of the
second oscillation, which is its maximum of retrograde velocity, must
now be found in the fluid stratum situated at the distance 1/4 _d_
from the centre of agitation, while the maximum of direct velocity is
found, at the same instant, in the stratum which is at the distance
3/4 _d_ from the centre of agitation.
The extent of the fluid, agitated by the two opposite
oscillations of the solid plane, is what we call the breadth of
an _entire undulation_, and we may consequently give the name of
_semiundulation_ to each of the parts actuated by the opposite
undulations; the whole constituting a _complete oscillation_, since
it comprehends the return of the vibrating plane to the initial
situation. It is obvious, that the two semiundulations, which compose
the complete undulation, exhibit, in [p120] the fluid strata which
they contain, velocities absolutely equal in magnitude, but with
contrary signs, that is to say, carrying the particles of the fluid
in opposite directions. These velocities are the greatest in the
middle of each of the semiundulations, and decrease gradually towards
their extremities, where they entirely vanish: so that the points
of rest, and of the greatest velocities positive and negative, are
separated from each other by intervals of one fourth of an undulation.
The length of an undulation, _d_, depends on two things: first, on
the promptitude with which the motion is propagated in the fluid;
and secondly, the duration of the complete oscillation of the
vibrating plane; for the longer this duration, and the more rapid the
propagation of the motion, the greater will be the distance to which
the first agitation has been extended at the instant of the return of
the solid plane to its initial situation. If the oscillations are all
performed in the same medium, the velocity of propagation remaining
the same, the length of the undulations will be simply proportional
to the duration of the oscillations of the vibrating particles from
which they originate. As long as the vibrating particles continue
to be subjected to the same forces, it follows from the principles
of mechanics that each of their minute oscillations will occupy the
same time, whatever their extent may be; so that the corresponding
undulations of the fluid will continue to be of the same length; they
will only differ from each other in the greater or less extent of the
elementary vibrations of the particles, which will be proportional
to the extent of the luminous particles; for it appears from what
has already been stated, that each stratum of the fluid repeats
exactly all the motions of the vibrating particle. The greater
or less amplitude of the oscillations of the strata of the fluid
determines the degree of absolute velocity with which they move, and
consequently the energy, but not the nature of the sensation which
they excite, which must depend, according to every analogy, upon
the duration of the oscillations. It is thus that the nature of the
sounds, transmitted by the air to our ears, depends entirely on the
duration of each of the oscillations executed by the air, or by the
sonorous [p121] body which puts it in motion; and that the greater
or less amplitude or energy of the oscillations only augments or
diminishes the intensity of the sound, without changing its nature,
that is, its tone, or pitch.
The intensity of the light must depend then on the intensity of
the vibrations of the ether; and its nature, that is to say, the
sensation of colour that it produces, will depend on the duration
of each oscillation, or on the length of the undulation, the one of
these being proportional to the other. [We find, however, nothing in
light of the same colour that is at all analogous to the different
register, quality, or _timbre_ of a sound; by which, for instance,
the sound of a violin differs from that of a flute in unison with it:
the subordinate, or harmonic tones of the sound having nothing in
light to correspond with them. TR.]
The duration of the elementary oscillation remaining the same, the
absolute velocity of the ethereal particles, at the corresponding
periods of the oscillatory motions, is, as we have seen, proportional
to its extent. It is the square of this velocity, multiplied by the
density of the fluid, that represents what is called the living force
in mechanics, or otherwise the energy or impetus of the particles,
which is to be taken as the measure of the sensation produced, or of
the intensity of the light: thus, for example, if in the same medium,
the amplitude of the oscillation is doubled, the absolute velocities
will also be doubled, and the living force, or the intensity of the
light, will be quadrupled.
We must, however, take care not to confound this absolute velocity
of the particles of the fluid with the velocity of the propagation
of the agitation. The first varies according to the amplitude of
the oscillations; the second, which is nothing but the promptitude
with which the motion is communicated from one stratum to the other,
is independent of the intensity of the vibrations. It is for this
reason, that a weak sound is transmitted by the air with the same
velocity as a stronger one; and that the least intense light is
propagated with the same rapidity as the brightest. When we speak
of the velocity of light, we always speak of the velocity of its
propagation. Thus, when we say that light passes through 200 thousand
[p122] miles in a second, we do not mean, according to the undulatory
system, that such is the absolute velocity of the ethereal particles;
but that the motion communicated to the ether employs only a second
to pass to a stratum at the distance of 200 thousand miles from its
origin.
In proportion as the undulation becomes more distant from the centre
of agitation, the motion, spreading over a greater distance, must be
weakened in every part of the wave. It is shown by calculation, that
the amplitude of the oscillatory motion, or the absolute velocity
of the particles concerned in it, is inversely proportional to the
distance from the centre of agitation. Consequently, the square
of this velocity is inversely proportional to the square of the
distance, and the intensity of the light must be inversely as the
square of the distance from the luminous point. It must be remarked,
that, for the same reasons, the sum of the living forces of the
whole undulation remains unaltered; for, on one side the length
of the undulation _d_, which may also be called its thickness, is
invariable, and its extent of surface augmenting in proportion to
the square of the distance from the centre, the quantity, or mass of
the fluid agitated, is proportional to the same square: and since
the squares of the absolute velocities are diminished in the same
proportion as the masses have augmented, it follows that the sum of
the products of the masses by the squares of the velocities, that
is to say, the sum of the living forces, remains unaltered. It is a
general principle of the motion of elastic fluids, that however the
motion may be extended or subdivided, the total sum of the living
forces remains constant; and this is the principal reason why the
living force must be considered as the measure of light, of which the
total quantity always remains very nearly the same, at least as long
as it continues to pass through perfectly transparent mediums.
It may be remarked, that black substances, and even the most
brilliant metallic surfaces, by no means reflect the whole of the
light which falls on them; bodies which are imperfectly transparent,
and even the most transparent, when of great thickness, absorb also,
to use a common expression, a considerable portion of the light that
is passing through [p123] them: but it must not be inferred that
the principle of living forces is inapplicable to these phenomena;
it follows, on the contrary, from the most probable idea that can
be formed of the mechanical constitution of bodies, that the sum
of the living force must remain always the same, as long as the
accelerating forces tending to bring the particles to their natural
positions remain unchanged, and that the quantity of living force
which disappears in the state of light, instead of being annihilated,
is reproduced in the form of heat.
In order to obtain a correct idea of the manner in which the
oscillation of a small solid body occasions undulations in an elastic
fluid, it has been only necessary to consider a complete oscillation
of the solid plane, which produces an entire undulation. If we
suppose the oscillations of the plane to be continually repeated,
we shall have a series of undulations instead of a single one: and
they will follow each other without intermission, provided that the
vibrations of the particle first agitated have been regular. Such a
series of regular and uninterrupted luminous motions I call a _system
of undulations_.
It is natural to suppose, on account of the prodigious rapidity
of the vibrations of light, that the luminous particles may
perform a great number of regular oscillations in each of the
different mechanical situations in which they are placed during
the combustion or the incandescence of the luminous body, although
these circumstances may still succeed each other in extremely short
periods; for the millionth part of a second is sufficient to exhibit,
for example, 545 millions of undulations of yellow light; so that
the mechanical disturbances, which derange the regular succession
of the vibrations of the luminous particles, or which even change
their nature, might be repeated a million times in a second without
preventing the regular succession of more than 500 millions of
consecutive undulations in each state of the particle. We shall soon
have occasion to apply this observation to the determination of the
circumstances in which the interference of luminous waves is capable
of producing sensible effects.
We have seen that each undulation produced by an oscillatory motion
was composed of two semiundulations, which [p124] occasioned in the
particles of the fluids velocities exactly equal in their intensity,
though opposite in the direction of the motions. Let us at first
suppose that two whole undulations, moving in the same line and in
the same direction, differ half an undulation in their progress:
they will then be superinduced on each other through one half of
their length, or of their breadth, as we should say in speaking
of the waves of a liquid: but I here use in preference the term
length as applied to the interval between the two points which are
similarly affected by the motions of two consecutive undulations.
In the supposed case of the coincidence of one half of each of the
undulations, the interference will only take place with respect to
the parts so coinciding: that is, to the latter half of the first
undulation, and the preceding half of the second: and if these two
semiundulations are of equal intensity, since they tend to give, to
the same points of the ether, impulses directly opposite, they will
wholly neutralise each other, and the motion will be destroyed in
this part of the fluid, while it will subsist without alteration in
the two other halves of the undulations. In such a case, therefore,
half of the motion only would be destroyed.
If now we suppose that each of these undulations, differing in their
progress by half the whole length of each, is preceded and followed
by a great number of other similar undulations; then, instead of
the interference of two detached undulations, we must consider the
interference of two systems of waves, which may be supposed equal
in their number and their intensity. Since, by the hypothesis, they
differ half an undulation in their progress, the semiundulations of
the one, which tend to cause in the particles of ether a motion in
one direction, coincide with the semiundulations of the other, which
urge them in the opposite direction, and these two forces hold each
other in equilibrium, so that the motion is wholly destroyed in the
whole extent of these two systems of waves, except the two extreme
semiundulations, which escape from the interference. But these
semiundulations will always constitute a very small part of the whole
series to be considered.
This reasoning is obviously applicable to such systems only [p125]
as are composed of undulations of the same length; for if the waves
were longer one than the other, however small their difference might
be, it would happen at last that their relative position would not
be the same throughout the extent of the groups; and while the
first destroyed each other almost completely, the following ones
would be less in opposition, and would ultimately agree completely
with each other: hence there would arise a succession of weak and
strong vibrations analogous to the beatings which are produced by
the coincidence of two sounds differing but little from each other
in their tone; but these alternations of weaker and stronger light,
succeeding each other with prodigious rapidity, would produce in the
eye a continuous sensation only.
It is very probable that the impulse of a single luminous
semiundulation, or even of an entire undulation, would be too weak
to agitate the particles of the optic nerve, as we find that a
single undulation of sound is incapable of causing motion in a body
susceptible of a sympathetic vibration. It is the succession of the
impulse, which, by the accumulation of the single effects, at last
causes the sonorous body to oscillate in a sensible manner; in the
same manner as the regular succession of the single efforts of a
ringer is at last capable of raising the heaviest church bell into
full swing. Applying this mechanical idea to vision, supported as it
is by so many analogies, we may easily conceive that it is impossible
for the two remaining semiundulations, which have been mentioned, to
produce any sensible effect on the retina; and that the result of
such a combination of the two systems must be the production of total
darkness.
If again we suppose the second system of undulations to be again
retarded half an undulation more, so as to make the difference of the
progress an entire undulation, the coincidence in the motions of the
two groups will be again restored, and the velocities of oscillation
will conspire and be augmented in the points of superposition; the
intensity of the light being then at its maximum.
Adding another semiundulation to the difference in the progress of
the two systems, so as to make it an interval and [p126] a half, it
is obvious that the semiundulations, superinduced on each other,
will now possess opposite qualities, as in the case of the half
interval first supposed: and that all the undulations must in this
manner be neutralised, except the extreme three semiundulations on
each side, which will be free from interference. Thus almost the
whole of the motion will again be destroyed, and the combination of
the two pencils of light must produce darkness, as in the case first
considered.
Continuing to increase the supposed difference by the length of a
semiundulation at each step, we shall have alternately complete
darkness and a maximum of light, accordingly as the difference
amounts to an odd or an even number of semiundulations: that is,
supposing always that the systems of undulations are of equal
intensity: for if the one series were less vivid than the other, they
would be incapable of destroying them altogether: the velocities of
the one series would be subtracted from those of the other, since
they would tend to move the particles of the ether in contrary
directions, but the remainders would still constitute light, though
feebler than that of the strongest single pencil. Thus the second
pencil would still occasion a diminution of the light: but the
diminution would be the less sensible as the pencil is supposed to be
weaker.
Such are the consequences of the principle of the interference
of undulations, which agree perfectly, as we have seen, with the
law of the mutual influence of the luminous rays which is deduced
from experiment: for the results are expressed precisely in the
same words, if we give the name of _length of undulation_ to the
difference of routes which had been represented by the symbol _d_.
Admitting, therefore, as there is every reason to believe, that light
consists in the undulations of a subtile fluid, the period _d_, after
which the same effects of interference are repeated, must be the
length of an undulation.
It appears from the table already given for the seven principal
kinds of coloured rays, that this period _d_, or the length of the
undulation, varies greatly, according to the [p127] colour of the
light, and that for the extreme red rays, for example, it is [more
than] half as great again as for the violet rays situated at the
other extremity of the spectrum.
It may easily be imagined that the number of different undulations is
not limited to the seven principal ones which are indicated in the
table, and that there must be a multitude of intermediate magnitudes,
and others beyond the red and the violet rays: for the ponderable
particles, of which the oscillations give rise to them, must be
subjected to forces that are infinitely varied, in the combustion
or the incandescence of the bodies which excite the motions of the
ether: and it is on the energy of these forces that the duration
of each oscillation depends, and consequently the length of the
undulation produced by it. It is found that all the undulations
comprehended [in the air] between the lengths .0000167 E.I. and
.0000244, are visible; that is, are capable of exciting vibrations in
the optic nerve: the rest are only sensible by their heat, or by the
chemical effects which they produce.
It has been remarked, that when two systems of waves differ half
an undulation in their progress, two of the semiundulations must
escape from interference; that six must be exempt when the difference
amounts to three semiundulations; and that, in general, the number
of undulations exempt from interference is equal to the number of
lengths of a semiundulation separating the corresponding points of
the two systems. While this number is very small in proportion to
that of the waves contained in each system, the motion must be nearly
destroyed, as in the case of the exemption of a single undulation.
But it may be imagined that, as we increase the difference of
the progress of the two pencils, the undulations exempted from
interference may become a material portion of each group, and that
it may finally become so great as to separate the groups entirely
from each other; and in this case the phenomena of interference would
no longer be observable. If, for example, the groups of undulations
consisted but of a thousand each, a difference of one-twentieth of an
inch in their routes would be much more than sufficient to prevent
the interference of the rays of all kinds. [p128]
But there is another much more powerful reason which prevents our
perceiving the effects of the mutual influence of the systems of
waves when the difference of their routes is considerable; which is
the impossibility of rendering the light sufficiently homogeneous:
for the most simple light that we can obtain consists still of an
infinity of heterogeneous rays, which have not exactly the same
length of undulation; and however slight the difference may be, when
it is repeated a great number of times, it produces of necessity, as
we have already seen, an opposition between the modes of interference
of the various rays, which then compensates for the weakening of some
by the strengthening of others; [while the shades of colour are not
sufficiently distinct to allow the eye to remark the difference.]
This is without doubt the principal reason why the effects of the
mutual interference of the rays of light become insensible when the
difference of the routes is very considerable, so as to amount to 50
or 60 times the length of an undulation.
It has already been laid down as one of the conditions necessary for
the appearance of the phenomena of interference, that the rays which
are combined should have issued at first from a common source: and it
is easy to account for the necessity of this condition by the theory
which has now been explained.
Every system of waves, which meets another, always exercises on
it the same influence when their relative positions are the same,
whether it originates from the same source or from different sources;
for it is clear that the reasons, by which their mutual influence
has been explained, would be equally applicable to either case. But
it is not sufficient that this influence should exist, in order that
it may become sensible to our eyes: and for this purpose the effect
must have a certain degree of permanence. Now this cannot happen when
the two systems of waves which interfere are derived from separate
sources. For it is obvious that the particles of luminous bodies,
of which the vibrations agitate the ether, and produce light, must
be liable to very frequent disturbances in their oscillations, in
consequence of the rapid changes which are taking place around them,
which may [p129] nevertheless be perfectly reconciled, as we have
seen, with the regular continuance of a great number of oscillations
in each of the series separated by these perturbations. This being
admitted, it is impossible to suppose that these perturbations should
take place simultaneously and in the same manner in the vibrations
of separate and independent particles; so that it will happen, for
example, that the motions of the one will be retarded by an entire
semioscillation, while those of the other will be continued without
interruption, or will be retarded by a complete oscillation, a change
which will completely invert the whole effects of the interference of
the two systems of undulations which originate from them; since if
they had agreed on the first supposition, they would totally disagree
on the second. Now these opposite effects, succeeding each other with
extreme rapidity, will produce in the eye a continuous sensation
only, which will be a mean between the more or less lively sensations
that they excite, and will remain constant, whatever may be the
difference of the routes described.
But the case is different when the two luminous pencils originate
from a common source: for then the two systems of waves, having
originated from the same centre of vibration, undergoing these
perturbations in the same manner and at the same instant, undergo no
changes in their relative positions: so that if they disagreed in the
first instance at any given point, they would continue to disagree at
all other times; and if their motions cooperated at first, they would
continue to agree as long as the centre of vibration continued to be
luminous: so that in this case, the effects must remain constant,
and must therefore be sensible to the eye. This is therefore a
general principle, applicable to all the effects produced by luminous
undulations; that in order to become sensible, they must be permanent.
We have hitherto supposed that the two systems of waves were moving
exactly in the same direction, and that consequently their elementary
motions, to be combined with each other, were precisely limited to
one single line: this is the simplest case of interference, and the
only one in which the one motion can be completely destroyed by the
other: [p130] for in order that this effect may be produced, not only
the two forces must be equal and in contrary directions, but they
must also act in the same right line, or be directly opposed to each
other.
The phenomenon of coloured rings, and that of the colours developed
by polarised light in crystallised plates, present a particular case
of interference, in which the undulations are exactly parallel. But
in the phenomena of diffraction, or in the experiment with the two
mirrors, which has been already described, the rays which interfere
always form sensible though very small angles with each other. In
these cases the impulses to be combined with each other at the same
points, as belonging to the two systems of undulations, will also act
in directions forming sensible angles with each other: but on account
of the smallness of these angles, the result of the two impulses
is almost exactly equal to their sum, when the impulses act in the
same direction, and to their difference, when they are in contrary
directions. Thus, in the points of agreement or disagreement, the
intensity of the light will be the same as if the directions agreed
more perfectly; at least the nicest eye will not be able to discover
any difference in them. But although, with respect to the intensity
of the light, this case of interference resembles that which has
already been considered, there are other differences which modify the
phenomenon very greatly, both with respect to its general form, and
to the circumstances necessary for producing it.
We may take, as a convenient example, the case of diverging rays
originating from the same luminous point, and reflected by two
mirrors slightly inclined to each other, so as to produce two pencils
meeting each other in a sensible angle: the two systems of waves
will then meet each other with a slight inclination; and it follows
from this obliquity, that if a semiundulation of the first system
coincides perfectly in one point with a semiundulation of the second,
urging the fluid in the same direction, it must separate from it to
the right and left of the point of intersection, and must coincide,
a little further off, on one side with the preceding semiundulation
which is in a contrary direction, [p131] and on the other side with
the following semiundulation, and then be separated from this again,
and at a distance twice as great as the first, must coincide with
the second semiundulation before and behind it, of which the actions
will coincide with its own: whence there will arise, on the surface
of this undulation, a series of lines, at equal distances from each
other, in which the motion is destroyed and doubled alternately by
the action of the second series. Thus if we receive this luminous
undulation on a white card, we shall observe on it a series of
dark and bright stripes, if the light employed is homogeneous; or
coloured fringes of different tints, if we employ white light for the
experiment.
[Illustration: untitled, diagram of two mirrors and reflected
undulations]
This will be more easily understood by the inspection of a figure,
which represents a section of the two mirrors and of the reflected
undulations, formed by a plane drawn from the luminous point
perpendicularly to the mirrors represented by DE and DF. The luminous
point is supposed to be S, and A and B are the geometrical positions
of its two images, which are determined by the perpendiculars SA
and SB falling from S on the mirrors, taking in them PA = SP [p132]
and QB = SQ. The points A and B, thus found, are the centres of
divergence of the rays reflected from the respective mirrors,
according to the well known law of reflection. Thus, in order to
have the direction of the ray reflected at any point G of the mirror
DF, for example, it is sufficient to draw a right line through B and
G, which will be the direction of the reflected ray. Now it must be
remarked, that, according to the construction by which the position
of B is found, the distances BG and SG will be equal, and thus the
whole route of the ray coming from S and arriving at _b_, is the
same as if it had come from B. This geometrical truth being equally
applicable to all the rays reflected by the same mirror, it is
obvious that they will arrive at the same instant at all the points
of the circumference _n′bm_, described on the point B as a centre,
with a radius equal to B_b_; consequently this surface will represent
the surface of the reflected undulation when it arrives at _b_, or,
more correctly speaking, its intersection with the plane of the
figure: the surface of the undulation being understood as relating
to the points which are similarly agitated at the same instant: the
points being all, at the commencement of the whole oscillation, for
example, or at the middle or the end, completely at rest; and in the
middle of each semioscillation, possessed of the maximum of velocity.
In order to represent the two systems of reflected undulations, there
are drawn, with the points A and B for their centres, two different
series of equidistant arcs, separated from each other by an interval
which is supposed equal to the length of a semiundulation. In order
to distinguish the motions in opposite directions, the arcs on which
the motions of the ethereal particles are supposed to be direct, are
represented by full lines, and the maximum of the retrograde motions
are indicated by dotted lines. It follows that the intersections
of the dotted lines with the full lines are points of complete
discordance, and of course show the middle of the dark stripes; and,
on the contrary, the intersections of similar arcs show the points
of perfect agreement, or the middle of the bright stripes. The
intersections of the arcs of the same kind are joined by the dotted
lines _b′p′_, _br_, _b′p′_, and those of arcs of [p133] different
kinds by the full lines _n′o′_, _no_, _no_, _n′o′_: these latter
representing the successive positions or the trajectories of the
middle points of the dark stripes, and the former the trajectories of
the bright bands.
It has been necessary to magnify very greatly in this figure the real
length of the luminous undulations, and to exaggerate the mutual
inclination of the two mirrors, so that we must not expect an exact
representation of the phenomenon, but merely a mode of illustrating
the distribution of the interferences, in undulations which cross
each other with a slight inclination.
It is easy to deduce from geometrical considerations, that the length
of these fringes is in the inverse ratio of the magnitude of the
angle made by the two pencils which interfere, and that the interval,
comprehended between the middle points of two consecutive dark or
bright bands, is as much greater than the length of the undulation,
as the radius is greater than the sine of the angle of intersection.
In fact the triangle _bni_, formed by the right line _bi_, and the
two circular arcs _ni_ and _nb_, may be considered as rectilinear
and isosceles, on account of the smallness of the arcs; and the
sine of the angle _bni_, considered as very small, may be called
_ib_/_bn_: so that _bn_ being the radius, _ib_ will represent the
sine of the angle _bni_, which has its legs perpendicular to those
of the angle A_b_B: consequently, these angles being equal, one of
them may be substituted for the other; and representing by _i_ the
angle A_b_B, formed by the reflected rays, we have _bn_ = _ib_/sin
_i_; consequently _nn_, which is twice _bn_, will be equal to
2_ib_/sin _i_. But _nn_ is the distance between the middle points
of two consecutive dark stripes, and is the distance which has
been called the breadth of a fringe; and _ib_ being the breadth
of a semiundulation, according to the construction of the figure,
2_ib_ will be that of a whole undulation; consequently the breadth
of a fringe may be said to be equal to the length of an undulation
divided by the [numerical] sine of the angle made by the reflected
rays [p134] with each other, which is also the angle under which the
interval AB would appear to an eye placed at _b_. We find another
equivalent formula, by remarking that the two triangles, _bni_ and
A_b_B, are similar, whence we have the proportion _bn_: _bi_ = A_b_
: AB, and _bn_ = (_bi_ × A_b_)/AB, or 2_bn_ = (2_bi_ × A_b_)/AB:
which implies that we may find the numerical breadth of a fringe
by multiplying the length of an undulation by the distance of the
images A and B from the plane on which the fringes are measured, and
dividing the product by the distance of the two images.
It is sufficient to inspect the figure, in order to be convinced of
the necessity of having the two mirrors nearly in the same plane, if
we wish to obtain fringes of tolerably large dimensions; for in the
little triangle _bni_, the side _bi_, which represents the length of
a semiundulation, being little more than the hundred thousandth of an
inch for the yellow rays, for example, the side _bn_, which measures
the half breadth of a fringe, can only become sensible when _bn_
is very little inclined to _in_, so that their intersection may be
remote from _ib_; and the inclination of _bn_ to _in_ depends on the
distance AB, which is the measure of the inclination of the mirrors.
If A and B, instead of being the images of the luminous point, were
the projections of two very fine slits cut in a screen RN, through
which the rays of light were admitted from a luminous point placed
behind the screen in the continuation of the line _b_DC, the two
paths described between the point and the slits A and B being equal,
it would be sufficient to compute the paths described by the rays,
beginning from A and B, in order to have the differences of their
lengths; and it is obvious in this case, that the calculations which
we have been making of the breadth of the fringes, produced by the
two mirrors, would remain equally applicable, at least as long as
each slit remained narrow enough to be considered as a single centre
of undulation, relatively to the inflected rays which it transmits.
It may therefore be said that the breadth of the fringes, produced
by two very fine slits, is equal to the length of an undulation
supposed [p135] to be multiplied by the interval between the two
slits, and divided by the distance of the screen from the wires of
the micrometer employed for measuring the fringes.
This formula is also applicable to the dark and bright stripes which
are observed in the shadow of a narrow substance, substituting the
breadth of this substance for the interval which separates the two
slits, as long as the stripes are far enough from the edges of the
shadow: for when they approach very near to the edges, it is shown,
both by theory and by experiment, that this calculation does not
represent the facts with sufficient accuracy; and it is not perfectly
correct in all cases, either for the fringes within the shadow, or
for those of the two slits, but only for the fringes produced by the
mirrors, which exhibit the simplest case of the interference of rays
slightly inclined to each other. In order to obtain from the theory,
a rigorous determination of the situation of the dark and light
stripes in the two former cases, it is not sufficient to calculate
the effect of two systems of undulations, but those of an infinite
number of similar groups must be combined, according to a principle
which will shortly be explained, in treating of the general theory of
diffraction.
ii. _Rule for the Correction of a_ LUNAR OBSERVATION. _By_ Mr.
WILLIAM WISEMAN, _of Hull_.
RULE.
Add together the reserved logarithm (found as directed, page 111 and
112 of the Appendix to the third edition of the Requisite Tables) the
log. sines of half the sum, and half the difference of the apparent
distance, and difference of apparent altitudes, and 0.3010300, the
log. of 2. Then, to the natural number corresponding to the sum of
these four logarithms, add the natural verse sine of the difference
of true altitudes, and the sum will be the natural verse sine of the
true distance.
Or, having obtained the natural number, as directed above, subtract
it from the natural cosine of the difference of the true altitudes,
and the remainder will be the natural cosine of the true distance.
[p136]
EXAMPLE.
(_From page 112, Appendix to Requisite Tables_.)
Reserved log. from Tables (Req.) 9th and 11th 9.9938860
Log. sin. 43° 23′ 5″ = 1/2 sum of app. dist. and diff.
app. altitudes 9.8368895
Log. sin. 6° 45′ 36″ = 1/2 diff. ditto ditto 9.0708157
Log. of 2 0.3010300
---------
Nat. num. to sum of 4 logarithms .1594488 9.2026212
Nat. vers. 37° 13′ 12″ = diff. true altitudes .2036812
-------
Nat. vers. 50° 26′ 28″ = true distance .3631300
Or, Nat. cos. 37° 13′ 12″ = diff. true altitudes .7963188
Nat. number found above .1594488
-------
Nat. cosin. 50° 26′ 28″ = true distance .6368700
DEMONSTRATION OF THE RULE.
Let M′, S′, D′, d′ and M, S, D, d, respectively denote the true and
apparent altitudes, distances, and differences of true and apparent
altitudes of the moon and sun (or a star); then will the theorem
answering to the above rule be expressed by
vers. D′ = ((2 cos M′ cos S′)/(cos M cos S)) sin 1/2(D + d) ×
sin 1/2(D−d) + vers. d′.
By Bonnycastle’s Trig. p. 175, the cosine of the angle contained
by the co-altitudes is
(cos D − sin M sin S)/(cos M cos S) =
(cos D′ − sin M′ sin S′)/(cos M′ cos S′);
consequently the verse sine of the same angle
= 1−(cos D − sin M sin S)/(cos M cos S) =
1−(cos D′ − sin M′ sin S)/(cos M′ cos S′); that is,
(cos M cos S + sin M sin S − cos D)/(cos M cos S) =
(cos M′ cos S′ + sin M′ sin S′ − cos D′)/(cos M′ cos S′).
Substituting cos d and cos d′ for cos M cos S + sin M sin S and
cos M′ cos S′ + sin M′ sin S′. (Bon. Trig. p. 282), we have
(cos d−cos D)/(cos M cos S) =
(cos d′−cos D′)/(cos M′ cos S′); whence
cos D′ = cos d′−((cos M′ cos S′)/(cos M cos S)) (cos d−cos D);
or, which is the same,
cos D′ = cos d′−((cos M′ cos S′)/(cos M cos S)) (vers D−vers d);
or, (Bon. Trig. p. 286.) [p137]
cos D′ = cos d′−((cos M′ cos S′)/(cos M cos S))·
(2 sin^2 ((1/2)D) − 2 sin^2 ((1/2)d)); that is,
cos D′ = cos d′−((2 cos M′ cos S′)/(cos M cos S)) sin ((1/2)(D + d))·
sin 1/2(D−d); whence
also vers D′ = vers d′ + ((2 cos M′ cos S′)/(cos M cos S)) ·
sin ((1/2)(D + d)) sin ((1/2)(D−d)).
It may be observed, that Requisite Tables 9–11, answer
logarithmically to (cos M′ cos S′)/(cos M cos S); and the verse
sines, and the cosines can be very readily taken out of the tables in
the Appendix. Also no ambiguity can arise from the application of the
rule before given: for all the arcs concerned in the operation will
always be (each of them) less than a quadrant, except the resulting
true distance, which cannot cause any ambiguity; and the verse sines
are given in the Appendix, to 126°.
EXAMPLE.
(_Example 2nd, p. 39, Requisite Tables_.)
Reserved log. from Tables 9 and 10 9.995307
Log. sin 62° 45′ 56″ = 1/2 sum app. dis. and diff. app. alts. 9.948971
Log. sin 40 43 31 = 1/2 diff. ditto ditto 9.814536
Log. 2 0.301030
--------
Nat. num. corres. 1.147741 0.059844
Nat. vers. 22° 48′ 16″ = diff. true alts. 0.078167 --------
--------
Nat. vers. 103 3 23 = true distance 1.225908
--------
_De l’Influence des Agens Physiques sur la Vie_. Par W. F. Edwards,
D.M., Membre associé de l’Académie royale de Médicine de Paris,
Membre de la Société Philomatique, de la Société de Médicine de
Dublin, &c.
The researches of science among the phenomena of the physical world
have long obtained a high degree of estimation and interest in
general society; but it is of late years only that their application
to living functions has attracted much of the attention of the
literary world.
The laws which govern the action of animal organs (the proper
department of Physiology) have usually been investigated by the
medical profession, to which they especially [p138] refer. Now
we find the public take some pains, and with reason, to inform
themselves upon subjects connected with physiological knowledge. A
well-educated person, disposed to philosophical inquiries, is not
merely contented with the consciousness of living, and the common
information he derives of its means by experience, but he seeks also
to comprehend the relations subsisting between his own organisation
and the matters with which he is surrounded, and which at once
furnish him with nutrition, life, and support, and assail him with
disease and annihilation. His own instincts and observation, joined
to the more learned experience of his medical advisers, help him
through the precarious stages of life, and these may perhaps be
sufficient for all its purposes; and under this impression many will
seek to know no more of the secrets of nature.
But we live in an inquiring and scrutinising age, when the demand
for scientific principles is very generally urgent. All, therefore,
relating to organisation seems of equal interest with that
appertaining to what is termed the physical creation or inert matter.
Under this impression we have perused the book before us with great
satisfaction, and propose to present our readers with an analysis of
the valuable materials which it contains. We have some knowledge of
Dr. Edwards, a countryman domiciliated in France, and long resident
in Paris. We have confidence in his reports, and highly estimate
his philosophical skill, extensive acquirements, and accuracy of
observation, ranking him among the first physiologists of the age.
The work, now under consideration, contains an elaborate account
of a long series of experiments, instituted for the purpose of
ascertaining the influence of the physical agents upon animal life.
These agents comprehend the atmospheric air, water, and temperature;
the two first constituting the media in which all animals exist, and
the last influencing in common the inhabitants of both media. It
is true, this is a subject by no means new, for it has engaged the
attention of experimenters from the earliest days of science. But
Dr. Edwards has diligently and patiently sought to investigate the
subject himself, to correct previous errors, and to embody the facts
which he has accumulated into a more complete and regular system than
heretofore adopted. In this attempt he has been eminently successful,
and has effected more perhaps than all who preceded him, availing
himself, nevertheless, of the experience of former inquiries.
The extent of his book, and the number of the experiments [p139]
are indeed somewhat appalling, but his clear and distinct method of
arrangement greatly facilitates the reader’s endeavours to master the
extensive subjects of his pages. As a book of reference it should
find a place in the library of every scientific society, and no
individual devoted to philosophy should omit the possession of it.
The agency of the air around us, water, and heat and cold, have
often been the objects of _chemical_ inquiry, from their known
great influence upon the animal economy. The changes effected by
the phenomena of animal life upon these agents have been accurately
examined, and partly reduced to a mathematical precision of
calculation.
Spallanzani and others have viewed the subject as it regards
physiology, but with such results as left the field open to
subsequent investigation. Dr. Edwards seems to have seized upon the
deficiencies of his predecessors, and, by going over their ground,
and extending his own inquiries, he has arrived at most interesting
and important results. These he has divided into four parts, as they
relate to the different orders of the animal creation. The first
part includes some of the lower animals, particularly tenacious of
life, and of cold blood, such as frogs, toads, and salamanders. The
second part is devoted to other animals of cold blood, and of the
vertebrated order, as fish, and those reptiles which include lizards,
snakes, and turtles. The third part refers to warm-blooded animals;
and the fourth part of the work is dedicated to the influence of the
physical agents upon the human race and vertebrated animals. To these
the author has added the discoveries of modern times, relative to
electricity on the animal economy, in an Appendix. A collection of
tables is appended to the work, exhibiting the principal series of
his experiments, as they regard the relative influence of physical
agents on the duration of life, and the phenomena resulting from
their mutual action.
The great importance of the four grand divisions of the work forbids
our hastily reviewing them, and we will endeavour to condense so much
of the information they contain as may forward the objects of our
analysis. Dr. Edwards thus announces the arrangement of his work:—
“Ces recherches auront donc rapport à l’air dans les conditions de
quantité, de mouvement et de repos, de densité et de raréfaction;
à l’eau liquide et à la vapeur aqueuse; à la température, dans ses
modifications de degré et de durée; à la lumière et à l’électricité.
Ces causes agissent à la fois sur l’économie animale, ordinairement
d’une manière sourde et imperceptible; et toujours [p140]
l’impression qu’on reçoit est le résultat de toutes ces actions
combinées.”
“Lors même que, par l’intensité de l’une d’elles, il nous arrive de
distinguer la cause qui nous affecte, l’observation de l’effet se
borne le plus souvent à la sensation, et les autres changemens qui
l’accompagnent nous échappent. On conçoit par la que l’observation
la plus attentive des phénomènes tels que la nature nous les
présente, ne saurait démêler dans cette combinaison d’actions
l’effet propre à chaque cause, ni reconnaître des effets qui ne
seraient pas révélés par la sensation.
“Il est une méthode qui règle les conditions extérieures, qui fait
varier celle dont on veut apprécier l’action, et qui fait juger,
par la correspondance entre ce changement et celui qui survient
dans l’économie, du rapport de cause et d’effet: c’est la méthode
expérimentale; c’est celle que j’ai suivie. Pour en tirer parti il
fallait, d’une part, déterminer l’intensité de la cause, d’autre
part celle de l’effet. La physique nous fournit ordinairement les
moyens de remplir la première indication.”
In the true spirit of philosophical investigation, Dr. Edwards, in
the first place, proceeds to examine the action of physical agents
upon the simplest forms, and least elaborately developed organised
beings, extending his inquiries upwards, in the scale of the animal
world, to man, the most perfect creature, and the ultimate object of
all physiological researches.
The peculiarity of constitution belonging to cold-blooded reptiles,
among which there is so little mutual dependance of organs, renders
these the best tests of the relative and proportionate influence
of the different agents, the intense action of which is liable to
destroy the more perfect animals; and the great development of the
nervous system in the higher orders gives them a wider and more
acute range of sensibility. It is difficult, at all times, and often
impossible, to insulate corporeal functions among the warm-blooded
classes, so as to ascertain the amount and limits of physical agency.
The four classes of vertebrated animals, or such as are furnished
with true spines, afford ample means of comparative illustrations;
and these departments have engaged the author’s attention, in order
to display the result of the action of the same agent exercising a
uniform influence upon constitutions very differently constructed.
The _air_, for example, exercises its influence uniformly upon he
four mentioned classes of vertebratæ, and their different families
are similarly exposed to the action of the atmosphere by respiration.
Curious and interesting as is this subject, it is singular [p141]
that, while it was among the first to be noticed, it has been
the latest in producing satisfactory results. Among the opposing
causes of the advancement of knowledge in this department, the
ignorance of our ancestors in _chemical_ science seems to be the
principal. Without chemical aid it is perfectly useless to attempt
the investigation. The composition of the air respired must be well
understood; the different gases must be carefully examined, or the
physiological inquiry will be darkened and obscured.
Dr. Priestley laid the foundation of our chemical knowledge of
gases in their relation to respiration; but some time elapsed
before it was understood in what manner the air was connected with
animal organisation. Oxygen gas, one of the known constituents of
atmospheric air, was Priestley’s discovery, in its effect upon the
blood, of converting this fluid from a dark purple to a bright
crimson. Lavoisier founded a chemical theory upon this discovery
of the agency of air, which was subsequently applied by Goodwin to
physiology. The latter author demonstrated, by a series of excellent
and correct experiments, that the exclusion of atmospheric air
produces death in animals, in consequence of the dark-coloured blood
usually circulating in the veins being prevented from becoming
crimsoned. The state in which any animal may be thus placed, is known
by the term ASPHYXY, and by which is to be understood a deficient
or suspended aërification of the blood, from whatever cause it may
proceed that the atmospheric air is prevented from access to the
blood as it circulates through the lungs.
The great French anatomist, Bichat, pursued this subject still
farther, and published a treatise on Asphyxy. He sought, by numerous
experiments, to determine the threefold relation of the air to the
nervous system, respiration, and the circulation; and he arrived at
this great and important conclusion, that the VENOUS OR DARK BLOOD
CIRCULATING THROUGH THE BRAIN, CREATES A CESSATION OF THE FUNCTIONS
OF THAT ORGAN, AND THAT IN CONSEQUENCE THE HEART LOSES ITS ACTION.
This discovery shows us at once the direct cause of asphyxy in all
its different degrees, according, in effect, to the vitiated state of
the blood from its deficient or suspended aërification.
Le Gallois also investigated the subject of asphyxy; and he found
that, when _dark blood circulated through the spinal marrow, the
motions of the heart ceased_; and thus he not only determined the
relations of the nervous system to atmospheric air, but also those of
the respiration and the circulation, [p142] explaining the action of
the air upon animals physiologically.
In this inquiry warm-blooded animals were almost exclusively referred
to.
Spallanzani certainly investigated the action of the air on animals
of cold blood, but less in relation to the three grand objects of
Bichat and Le Gallois; and Spallanzani had the misfortune to live in
an age when neither chemistry nor physiology had made such advances
as the present age has produced.
Messrs. Humboldt and Provençal have, indeed, supplied much of this
deficiency, by their researches into the respiratory functions of
fishes. Nevertheless, the ground was still open, and our author has
justly appreciated the extent of former inquiries, and observed that
the phenomena of cold-blooded animals were too extraordinary to be
noticed lightly, and required much more extensive observation than
was previously bestowed upon them. With this impression, he proceeded
to form an estimate of the comparative influence of the air and water
upon the nervous and muscular systems of cold-blooded animals, which
the singular modifications of life among reptiles in particular
afford ample means of ascertaining.
We know that these animals possess the extraordinary property
of existing a considerable time after the removal of the heart,
with the free exercise of their senses and of voluntary motion,
notwithstanding the suppression of the circulation. Dr. Edwards
accordingly selected _salamanders_ for his first investigations,
and removed the heart, with the bulb of the aorta. Two of these
were exposed to the free action of the air, and the other two were
submersed in water previously deprived of air by boiling; a similar
temperature being maintained in each medium. In four or five hours,
those submersed in the non-arëated water ceased to be active, unless
irritated, when they still appeared to retain voluntary power. One
died in eight, and the other in nine hours. The salamanders in air
lived from twenty to twenty-six hours and upwards. These comparisons
were frequently repeated, and upon frogs and toads, with the same
results, showing the experiments in air to be far more favourable
to their existence than with the animals submersed in the water.
Eight hours were about the maximum of the duration of life among
the animals submersed in the water, and twenty-nine among those
exposed to the air; so that, independently of respiration, the air
is thus proved to be the most proper [p143] medium for the action of
their nervous and muscular systems, in their insulated state, the
respiration and the circulation of the blood being both suspended. As
a further corroboration of the superior vivifying property of the air
over simple water, when the same animals were plunged into unaërated
water during a certain time, as soon as they were, removed into the
atmosphere, they instantly revived; and their nervous and muscular
systems were acted on according as they were placed in either medium.
Dr. Edwards also confirmed the observation of Goodwin relative to
the effect produced on the colour of the blood. Properly speaking,
the asphyxy comes on the instant the air is excluded, the shades of
difference in the colour of the blood being referrible to the air
left in the lungs after cessation of respiration.
The next point to determine was the influence of the air upon the
same animals exercising the respiratory function, and retaining their
circulation, compared with those deprived of these functions.
The difference of time in the two cases developes the influence which
the general circulation of the blood, free from aërial contact,
exercises upon the nervous system.
To ascertain this point, an equal number of frogs, deprived of the
power to exercise their respiratory and circulating functions,
together with others left entire, were respectively plunged into
disaërated water. At times the difference in favour of the untouched
animals was twenty-four hours in favour of the duration of life.
Similar trials with toads and salamanders produced the same results.
In each case _asphyxy_ came on; but the existence of the animals
which lived without the respiration and circulation was much
shortened. Thus the relative powers of life between the sole and
insulated action of the nervous system, and its action combined with
the circulation of dark blood, were estimated. The inference to be
deduced, therefore, is, that although disaërated blood furnishes
but an ephemeral sort of existence, it nevertheless exercises a
comparatively favourable influence upon the nervous and muscular
systems, since it tends to the prolongation of the action of these
animal functions.
Dr. Edwards next proceeds to investigate the phenomena of _asphyxy_
produced by _strangulation_, or the mechanical obstruction to the
access of air to the lungs, and consequently to the blood. The same
animals were employed. When the windpipe was rendered impervious by
ligature, the muscles of the animals seemed to be paralysed directly;
and although their motions became subsequently revived at times,
[p144] they never altogether recovered their perfect freedom. As a
comparative illustration, an equal number of frogs were submersed
in water, all of which died in about ten or eleven hours, while
those which were strangled lived from one to five days. Salamanders
continued active longest, and one did not cease to exist till the
eleventh day, although during this time he was in a complete state of
_asphyxy_ from perfect strangulation.
Dumeril once found that a salamander lived a long time after
decapitation, even when the cicatrix of the wound was healed so as to
stop all access of air to the lungs.
In comparing the effects of strangulation with those of submersion
or drowning, it is to be supposed either that these animals exist a
limited period without the necessity of the nervous system being in
contact with atmospheric air, or that the air influences their blood
through the integuments of the body. Accordingly Dr. Edwards put this
to the test by making experiments upon _cutaneous respiration_.
Spallanzani found that the exposure of cold-blooded animals to the
air was attended with exudation of _carbon_, a phenomenon similar
to that of respiration. There appears, however, to be some source
of error in these experiments, for Spallanzani removed the lungs,
and this operation rendered the animal liable to the absorption of
air and loss of blood. Dr. Edwards sought to effect the same purpose
by a different and more successful measure. He also confined frogs
in vessels of atmospheric air, and fastened bladders round the head
and neck, tight enough to stop the entrance of air to the lungs. At
the expiration of two hours the air was examined in the bladder,
and it was found to contain an excess of _carbonic acid_. The same
result was obtained from salamanders. It appears, therefore, that
while air is in contact with the skin, _carbon_ is given out; but
whether this be the effect of exhalation merely, or that _oxygen_ is
actually absorbed, and _carbon_ transpired, is a question which led
to further inquiries. Dr. Edwards, therefore, inclosed cold-blooded
animals in _solid substances_, in order to determine the influence of
dark-coloured blood, free of all external agency, in the production
of chemical changes, and to observe its sensible effect upon the
nervous system.
In the year 1779 three toads were confined in a box hermetically
sealed, and so deposited in the Academy of Sciences. Eighteen months
after, the box was opened, and one toad was found dead. These animals
have been found alive in blocks of coal after an imprisonment of some
years, and have [p145] also been sealed up during similar periods
without perishing. Possibly some hole or crevice might have admitted
a little air. But, in Hevissant’s experiment of 79, care seems to
have been taken to obviate this suspicion.
Dr. Edwards, however, determined to put the question to the test.
He enclosed ten out of fifteen frogs in thick wooden boxes, and
filled the interstices with plaster, covering them over with the
same substance, the toads lying each in a central hole or bed. The
other five toads were at the same time submersed in water, and at
the expiration of eight hours they were found to be dead. In sixteen
hours more, one toad was taken from a box and found to be lively, and
was reconsigned to its prison. On the sixteenth day the toads in the
boxes were discovered alive, and thus the fact was established that
these animals can live far longer in a state of asphyxy confined in
solid substances, than when submersed in water. This was confirmed by
repeated trials on salamanders, frogs, and toads. The frogs perished
quickest.
Thus an extraordinary fact is established, as regarding reptiles,
since it affords an exception to the general rule that _all animals
require a_ CONSTANT _supply of fresh air for the maintenance of their
existence_.
Similar trials were repeated in sand, and with the same results.
Dr. Edwards found that although a certain quantity of air enters the
boxes and sand, yet that it is far too little to maintain life. His
conclusion, therefore, stands, that animals of the kind employed can
live longer in _solid substances_ than in a limited quantity of _dry
air_.
It remains, however, to be considered in what manner these animals
have their lives extended beyond those exposed to the action of a
body of air. Dr. Edwards supposes the _moisture_ of the sand to be
one cause, since in the dry air the animals become _desiccated_, the
cutaneous transpiration being lost in one case, and retained in the
other, by the exclusion of air. A rapid and abundant transpiration
from the body, united with deficiency of air, seems to be a greater
cause of dissolution than confinement in solid substances wherein
there is no waste by transpiration.
The author’s inquiries are next directed to the influence of
_temperature_ upon animals of cold blood, and two and forty
experiments are practised upon this subject, from the month of July
to September following, during which period frogs were submersed
in aërated water, with a view of settling the duration of life,
acted on by varieties of temperature. The [p146] continuance of
life, generally, in these experiments, varied from one to two hours
and twenty-seven minutes. The mean term of life was one hour and
thirty-seven minutes, as averaged in July, and in September one hour
and forty-five minutes, the two extremes of the seasons approximating
the effects. The duration of the frog’s existence was greatest in the
greatest depression of temperature. Thus at ten degrees the duration
of life was more than double what occurred at sixteen or seventeen
degrees, and at zero it was about triple. As the heat was increased,
the duration of life was diminished; at forty-two the frogs died, and
in the lowest temperature they lived longest.
It appeared that at zero the frogs did not become stiffened, but
retained their motion, and their resistance to the frozen state is
the cause of the continuance of their existence at a low temperature.
The cause of this resistance is to be found in their peculiarity of
constitution. Toads produced similar results.
It may be alleged that frogs naturally live in climates at from forty
to forty-two; but, it is to be observed, that they are then placed in
a situation of liberty to come to the surface of the water to respire
when they please; whereas in these experiments their respiration is
limited, from their inability to reach the surface.
Taking a wider range of temperature, Dr. Edwards sought to ascertain
the influence of the _seasons_. In July and September frogs were
found to live from one to two hours and twenty-seven minutes in
aërated water at fifteen and seventeen degrees. In November they
died at the end of more than double this period, under the same
temperature, and all other circumstances being similar excepting the
season. As the autumn advanced life was prolonged.
To what are we to ascribe the modifications of the seasons? Probably
to circumstances appertaining to the intensity of light, to
electricity, to temperature, to the pressure of the atmosphere, to
dryness and moisture, &c.? Such existing causes naturally suggest
themselves. But it appears that little or no account can be rendered
as to pressure, since its variations were too trifling during the
two seasons. Moisture could not effect an influence, because the
experiments were performed in water. The motion of the air was also
obviated. Of all the suggested modifications _temperature_ alone
acted, and this, as it related to the surrounding air, was rendered
ineffectual by artificial temperature. The animals, therefore,
could only be affected as to the temperature of the [p147] seasons
_by that which preceded the experiments_. The modifications of the
seasons, therefore, appeared to influence the cold-blooded animals
used in the experiments in this point of view only. Accordingly we
have this remarkable result, that the animals lived twice as long in
autumn as in the summer preceding, when plunged in water of equal
temperature. The _seasons_ evidently influence their constitutions,
so as to extend the duration of life independently of other causes,
that is, from summer to autumn. Dr. Edwards endeavoured to ascertain
if it proceeds from atmospheric temperature, and he found that frogs
lived in aërated water at ten degrees, during November, from five
or ten to eleven, and even to forty hours, in some instances, the
last term being about double the duration of life in water of the
same degree in summer. This proves the remarkable dependence of the
frog’s life under water, and the temperature of the month preceding.
Two curious facts are thus developed by experiments instituted at
different seasons. First, the influence of the temperature of the
water in which the animals were placed; and secondly, the influence
of the temperature of the air during certain periods preceding the
experiments, for in autumn the duration of life was about double
that of summer, and in winter he found the term to equal autumn,
the temperature of the air being in each comparative experiment
artificially raised to the same degree.
It appears from the foregoing experiments that frogs, toads,
and salamanders, exist in water according to its _lowness of
temperature_, and that their lives are prolonged _by the temperature
which precedes the experiment being lowered_. It then becomes a
question, what are the limits of this influence? This is to be
ascertained by observing the greatest duration of life among animals
deprived of external air by submersion in water; and noticing at
the same time all the favourable circumstances dependent on the
concurrent temperature in prolonging life among the cold-blooded
animals.
A point relative to the natural history of frogs first presents
itself to our notice. Spallanzani is of opinion that frogs do not
pass the winter under water, but retire in October from their native
rivers into moist sands, in which they make openings to breathe the
air through, called by the Italian fishermen _il respiro della ranà_.
M. Bose, and other French naturalists, found that frogs retire from
October to spring _into water_, but they give us no direct proof that
they constantly remain submersed. The presence of the observer may
alarm the frogs, and thus prevent [p148] their putting their heads
above the water, so that the assertion is but a negative kind of
proof that they remain so long under the water without coming up to
respire, as some affirm. M. Bose declares he watched frogs approach
the surface at regular periods every day during the winter season.
Under the most favourable circumstances Dr. Edwards found that frogs
could not remain submersed, in winter, more than two days and a half.
Frogs are less active during winter than at the other seasons, but
they never lose their motion. Were it true, as Spallanzani thinks
it is, that they remained so long under water, it is probable that
they would become frozen in winter and die. Spallanzani derives
his opinion from what occurs with fish, forgetting that frogs are
amphibious, and live as well on land as in water; whereas fish are
limited to a watery medium, and can, therefore, furnish no example.
Dr. Edwards found that frogs, placed in certain quantities of aërated
and non-aërated water of an equal temperature, lived longest in the
_former_; but that the difference was not constant in its results,
being often twice as long in one case as in the other, as to the
duration of life.
The next inquiry regarded _stagnant water renewed at intervals_, and
in this the duration of life was prolonged beyond the term of the
last experiments, and even to eight days. During winter when the
temperature was lowest the frogs remained active, though less so than
in spring.
The conclusions to be drawn from these experiments are, that frogs
pass the winter _in an animated state in water_, not becoming
stiffened as in ice, and that they need not to approach the surface
of the water in order to respire, provided the water they inhabit
be _renewed at intervals_; but if the water be not renewed, or if
disaërated water be employed, the frogs perish.
Considering that these animals are truly amphibious, these results
are very curious; and it is interesting in a physiological point of
view, to know that frogs are able to respire the air contained in the
dense medium of water for an indefinite period, and just as easily as
they breathe the finer medium on land.
Respecting the action of aërated water on the skin, the conclusion
drawn seems to be correct, that it must be from _cutaneous_
absorption that the air contained in the water promoted the
continuance of life in Dr. Edward’s experiments upon this point,
since the animals were in a state of _asphyxy_ regarding respiration
by the lungs; and that no [p149] air entered in combination with
water was shewn from Dr. Edwards _never having seen water in the
lungs_. Therefore, unless the air acted on the blood through some
other organ, the lives of these animals would be definite and
shortened, even though the water be renewed from time to time, and
their _asphyxy_ would be complete and continued. And since the skin
is the only organ in contact with the air, it is fair to conclude
that it is the medium of aërial absorption.
When the _webs_ were examined under water, these membranes indicated
the action of air upon their blood-vessels, by the bright tint of the
blood.
Spallanzani imagined that frogs perish sooner in _running_ than
in _stagnant_ water; but Dr. Edwards having secured some of these
animals in ten feet of the Seine, whilst others were simultaneously
placed in _unrenewed stagnant water_, he found the latter did not
survive many hours, and the former lived a long time.
In order to fix the limits of this kind of existence, frogs were
placed in _renewed aërated water_, and with a temperature never
forced beyond ten degrees they were found to live _in all seasons
of the year_; but when the temperature was elevated from twelve to
fourteen, they died in a few hours. In running streams they lived
longest, and at twelve degrees they were thus more favourably placed
than in stagnant water, _at a lower temperature even_, and taking
the precaution to renew the water daily; and at seventeen degrees
in running water they died prematurely. Toads exhibited the same
comparative results, but they lived the longest.
It appears, therefore, that water contained in vessels is less
favourable to the lives of these animals than running streams,
although the water and the temperature were identical. Probably the
great advantage of running water is its _constant and unceasing
renewal_. The separate and comparative influence of air, water,
and temperature, being thus investigated, the combined action
of the three physical agents was next inquired into, and it is
demonstrated that frogs submersed in water are influenced by three
circumstances,—1. the presence of _air_ in water; 2. the quantity of
its renewal; 3. the _temperature_ of the medium. If the manners of
frogs be closely examined, they appear to live in water under very
considerable influence from the atmosphere.
From circumstances developed in the foregoing experiments, _cutaneous
respiration_ seems to be pretty evidently indicated. A chapter is,
therefore, devoted to this subject, one that is not well known,
although pulmonary respiration is [p150] generally understood. In
frogs, the function of pulmonary respiration is united with that
of deglutition, and the air enters only by the nostrils, the mouth
being closed during respiration. While the mouth remains open, the
action of deglutition is stopped, and, therefore, the animal does
not then breathe. Dr. Edwards availed himself of this circumstance
by gagging the mouth so as to keep it open, and thus prevent the
air from entering the lungs. The frogs were sufficiently exposed to
moisture and renewal of air to their bodies: the results were, that,
at twenty-four degrees, five frogs so placed died next day, and one
lived a week.
Dr. Edwards immersed some frogs in wet sand, and adopted an improved
method of excluding air from the lungs, and some of them lived
twenty days. Hence it evidently appears that air influences the
skin materially, and counterbalances the asphyxious state induced
by obstructing the air’s passage to the lungs. By adopting other
methods, the existence of frogs was prolonged to thirty or forty
days. It is, therefore, sufficiently proved that the blood undergoes
its necessary changes from atmospheric influence through the medium
of the skin, although in a minor degree compared with those which it
passes through from pulmonary respiration. Frogs are thus shewn to
possess a double source of respiration.
By substituting _oil_ for water, frogs immersed in this fluid died
in a few hours, being at liberty to breath the air on its surface.
And, when plunged into oil, with the means of breathing by the lungs
arrested, they lived an equal time with frogs simultaneously placed
in water without power to respire. A comparison was instituted with
frogs in oil and in water, being allowed to breathe air, when the
difference was found to be very considerable in favour of the aquatic
bath. These circumstances shew, that, even with the feeble succour of
the air through the skin, absorbed from the water, the respiratory
function was far more prolonged, than in the case of the obstruction
afforded by the oil. Thus we have abundant evidence of the double
function by which frogs are maintained, from the action of the air on
the skin and the lungs; and this appears to be the means of existence
among _amphibious animals generally_.
It may be asked why these animals die in deep water when prevented
from approaching the surface? It appears that, having expelled the
respired air from their lungs, which is imperfectly renewed from the
water, they become specifically heavier than the water, and unable to
rise from the bottom; and thus placed, the duration of their lives
depends upon [p151] the resistance offered by their constitutions
to the depressing effects of a state of asphyxy while remaining
submersed.
Dr. Edwards next proceeds to inquire into the effects of
TRANSPIRATION. A liquid transfusion from the skin of animals is
constantly going on, either in the form of vapour or of fluid in a
denser state.
The latter constitutes sweat. This phenomenon exhibits great
variations, and it is important to know what diminution of weight the
body suffers in different circumstances. In the course of an hour
remarkable fluctuations occur.
Dr. Edwards suspended frogs, toads, and salamanders, in a _calm air_,
weighed them, and noted the results, which, though very changeable
in an hour, were generally uniform in three, and in nine hours they
averaged an equal result. The successive diminution in the mass of
fluids was evident.
The results were modified by the alternate position of the animals in
a body of air in repose, or agitated by a draft. And these results do
not appear to depend upon any principle of vitality, for they take
place equally in death and in life, and indeed among unorganized
bodies, as, for example, lumps of charcoal soaked in water. Therefore
the cause of the phenomenon of transpiration seems to be referrible
entirely to physical agents. The _motion of the air_ seems to be its
exciting cause; for even when, to all appearance, it is calm, it is
in reality agitated more or less, and produces a sensible evaporation
from the skin. But the difference between the effect of calm and
agitated air is remarkable; for in a draft, the animals exposed to
it sweated away double the quantity of liquid compared with those
confined in a room shut up. The amount lost was proportioned to the
_intensity of the wind_, and reached a triple amount over those
animals in stagnant air; and this fact explains the variations
noticed from hour to hour among animals exposed to currents of air.
The transpiration which occurs in very moist air, always amounts to a
diminution of weight; but in dry air it is five or ten times greater;
and when the influence of a moist state of the atmosphere is compared
with that of a dry state, the amount of evaporation is equal to that
of a dry and calm air.
Transpiration may, therefore, be referred to _the agitation of the
atmosphere_ for its exciting cause, beyond any modifications of its
_density_. And, although an elevated temperature be favourable to
transpiration, its modifying influence is less than that of other
causes.
In comparing the effects of _absorption_ and _transpiration_, [p152]
in water and in air, frogs were found to gain an addition to their
weight according to the term of their continuance in the former
medium. An absorption of water was rendered evident by the loss of
bulk it had sustained, when measured after the experiment.
Thus, when the comparative influence of water and air is estimated,
the former appears to be absorbed, and adds to the weight of the
body; and the latter tends to diminish the weight, by different and
fluctuating degrees of evaporation taking place, and dependent much
more on the degree of motion in the air, than on its dryness or
humidity: these last conditions modify evaporation in a minor degree,
when compared with the influence of a current of air.
The celerity of _absorption_ exceeds that of _transpiration_ six
times, in the most rapid cases. It therefore results, that the losses
by _transpiration_ in air should be repaid by absorption of water
in a much less time than the expenditure occurs. But the decrease
of weight is not prolonged; it is sudden, and not continuous,
alternating with augmentation of weight, by absorption of liquid
going on in a ratio superior to the loss; and thus nature’s provision
is manifested for the nutriment of the body.
With this last inquiry Dr. Edwards concludes the first part of
his work; and it is observed, that, with regard to transpiration,
the losses of weight have been considered without reference to
the existence of any other influence than water. The losses by
transpiration have been examined generally without regard to the
matters lost. What relates to water differs essentially in one
respect from that which regards the air. The losses sustained by the
body ought to be more particularly examined. Temperature and loss of
time require estimation. An excretion of _solid_ matter evidently
takes place; for the water, in which animals are submersed, becomes
turbid, especially in hot weather, and it sensibly contains animal
matters, affecting the weight of the body in water.
When animals are submersed in water, their skins exercise two
functions, acting inversely in determining their weight. And it
results, from comparative experiments, that the _absorption at
zero_ exceeds the _loss in water_; while at thirty degrees the
_loss_ exceeds the increase by weight from absorption; and the
higher the temperature, the greater is the excess in the discharge
of animal matters. We may therefore presume, that the agency of
_temperature_ produces analogous effects, upon aërial transpiration,
to those before observed [p153] in other inquiries; and the effects
of _dryness_ and _moisture_ in the air produce a minor degree of
influence also, when compared with _temperature_, on the losses of
animal substances.
We have been thus minute in our analysis, because the subject of
it is new to science in its present shape, and of a high degree of
interest. Dr. Edwards’s researches among the different classes of
animals have tended more to the illustration of the influence of
physical agents upon life than any previous authorities; and the
persevering industry, accuracy of observation, and patient inquiry
which he has evinced in his investigations among cold-blooded
animals, have placed this department of the creation in a point of
view at once curious, interesting, and valuable to science. We attach
the greater importance to this part of the author’s work, as it is
a ground on which he may be consulted, and quoted as indisputable
authority, until equal inquiries have shewn him to be fallacious.
Our limits will not at present permit us to proceed farther in our
analysis, and we must refer the remainder of the book to a future
opportunity. The subjects of the three other parts, though greatly
extended, will not probably require such minute analysis as those
novel experiments which form the subject of the first part; but we
imagine that the application of the principles laid down, in the
previous inquiries, to human physiology, will be found not less
interesting than those which relate to the natural history of the
lower orders of the animal creation.
_An Account of Professor Carlini’s Pendulum Experiments on Mont
Cenis_.
We believe that no account of Professor Carlini’s pendulum
experiments on Mont Cenis has hitherto appeared in the periodical
scientific publications of this country: the experiments are,
however, well deserving of such notice, having been conducted with
great care, and having had a specific object in view, which object
seems to have been satisfactorily accomplished. The following
brief account of them, taken from the original memoir published in
the Appendix to the “Ephéméride di Milano” for 1824, may not be
unacceptable to those of our readers who interest themselves in
subjects of this class.
The length of the simple pendulum vibrating seconds is a [p154]
measure of the intensity of gravitation; _i. e._ of the excess of the
force of gravity over the centrifugal force. In consequence of the
ellipticity of the earth, and of the difference in the direction of
the two forces, the intensity of gravitation varies according to the
different latitudes. It also varies, in the same latitude, according
to the greater or less elevation of the pendulum above the level of
the sea; _i. e._ according to its greater or less distance from the
centre of the attracting force.
Had the earth a perfectly level surface, such, for instance, as
it would have if it were everywhere covered by a fluid, the force
of gravity, in receding from the surface, would diminish in the
duplicate proportion of the distance from the earth’s centre. In the
actual state of the globe, however, its continents and its islands
are raised above the general level of the sea by which it is only
partially covered; and if a pendulum be raised, on the surface of
the land, to a known elevation above the sea, the diminution of
gravity will not be, as in the more simple case, proportioned to the
squares of the respective distances from the earth’s centre, but that
proportion will require to be modified, by taking into account the
attraction of the elevated materials, interposed between the general
surface and the place of observation.
When pendulums are employed in different latitudes, to obtain the
ratio of gravitation between the equator and the pole, for the
purpose of deducing the ellipticity of the earth, all the places
of observation, being on land, are more or less elevated above the
sea; inland stations, in particular, are sometimes at considerable
elevations: to render these results comparable one with another,
it is necessary to reduce each result to what it would have been,
had it been made at some level common to all the experiments; and
the surface of the sea has hitherto been taken as that common
level. Previous to the publication of a paper of Dr. Young’s in the
Philosophical Transactions for 1819, the consideration which we have
mentioned, that of the attraction of the matter interposed between
the place of observation and the level of the sea, was generally
unheeded in estimating the allowance to be made for the reduction
of different heights to the common level: in that paper, however,
Dr. Young took occasion to point out the probable effect of [p155]
the interposed matter in modifying considerably the usual allowance;
that, supposing its density to be about half the mean density of
the earth, the effect of an hemispherical hill of such matter, on
the summit of which the pendulum should be placed, would be to
diminish the correction, deduced from the duplicate proportion from
the earth’s centre, about 1/5th; that, in like manner, a tract of
table-land, considered as an extensive flat surface, of the same
relative density, would diminish the correction about 3/8ths; and
that, accordingly, in almost any country that could be chosen for
the experiment, the proper correction for the height would vary,
according to the form and density of the interposed materials, from
rather more than a half to rather less than three-quarters of the
usual allowance. This view has been subsequently acted upon by the
English pendulum experimentors, in reducing their observations;
but it has not been yet adopted by the French. The experiments of
Professor Carlini were calculated to afford a practical illustration
of the correctness of Dr. Young’s reasoning.
Professor Carlini was engaged, in the summer of 1821, in concert
with Professor Plana, in determining the amplitude of the celestial
arc between the Hospice on Mont Cenis and the Observatory at Milan,
by means of fire-signals made on the Roche Melon, and observed
simultaneously at Milan and at a temporary observatory established
at the Hospice. Whilst thus engaged, Professor Carlini, being
stationary for several days on Mont Cenis, and obliged to have time
very accurately determined, for the purpose of comparing with the
observatory at Milan, availed himself of the opportunity to employ
a pendulum apparatus of the same general nature as that used by M.
Biot at Paris, which had been prepared at Milan some years before,
under the direction of a commission of weights and measures, with the
view of determining the value of the divisions of the national linear
scale. As this apparatus differed in some few particulars from the
original employed in France, we shall briefly notice the differences,
presuming our readers to be acquainted with the apparatus of MM.
Borda and Biot.
1. In the Milan apparatus, by means of two microscopes furnished with
wire micrometers, the length of the pendulum [p156] may be measured
without touching it; without approaching it; without even opening the
case which contains it. The measure is obtained by bringing the wires
in contact with the images of the knife-edge suspension, and of the
upper and lower borders alternately of the platinum disk suspended to
the thread: thus preventing the risk of deranging the equilibrium,
and avoiding the effect which the heat of the body might have on the
dilatable metallic thread.
2. The half sum of the distances taken between the suspension, and
the upper and lower edges of the disk, gives the distance of the
centre of the disk itself; without measuring its diameter with a
compass, an operation exceedingly difficult to execute with the
necessary precision. By this apparatus of microscopes the length may
be measured at pleasure, even during the time of oscillation; and
being attached to the wall, instead of supported by the floor, the
risk of derangement by the tread of the observer is avoided.
3. The pendulum, and the clock by which its oscillations are
measured, were not, as usually, near together and resting on the
same base, but were perfectly separated. The coincidences of the
oscillations were observed, by bringing the image of the pendulum of
the clock, reflected by means of an oblique mirror, in contact with
the image of the simple pendulum seen direct through a telescope. By
this modification the risk of the mutual influence of the pendulum
and the clock is avoided.
4. The disk was attached to the thread by means of knots in the
thread itself; avoiding the correction for the small cup usually
employed for that purpose.
5. An alteration was made in the weight and shape of the knife-edge
suspension; reducing its weight to about 10 grains, and giving it the
shape of a rotella, instead of that of a triangular prism.
The simple pendulum and microscopes were attached to a strong
wall, in a room on the ground floor, contiguous to the temporary
observatory, and well sheltered from the sun and weather. The clock
with which the pendulum was compared, was supported by a pyramid of
masonry resting on the ground, and occupying the middle of the room.
The experimental length between the microscopes was referred to three
standard metres, [p157] in perfect agreement with each other: one
received from Paris by the Commission of Weights and Measures at
Milan; a second brought more recently from Paris by Conte Moscati;
and a third in the possession of the Royal Academy of Turin.
The experiments were commenced on the 3rd of September, and
terminated on the 27th, being interrupted by M. Carlini’s absence
at Chambery from the 7th to the 12th. The distance between the
microscopes, and the oscillations and length of the pendulum,
were measured alternately. Thirteen independent results were thus
obtained, of which the greatest discordance from the mean was not
more than 13/10000ths of a British inch. The mean result was 39.0992
British inches, the length of the pendulum vibrating seconds in a
vacuum, at the place of observation on Mont Cenis, 1943 metres, or
6374 feet above the sea, in the latitude of 45° 14′ 10″. To compare
with this determination, we may obtain a tolerably fair approximation
to the pendulum at the level of the sea in the latitude of 45° 14′
10″, such as its length might have been found, if the mountain could
have been removed and the pendulum placed on its site, by deduction
from the lengths actually measured with a similar apparatus, on the
arc between Formentera and Dunkirk, at stations not far removed from
the level of the sea, in the adjacent parallels to Mont Cenis, and in
the countries adjoining. Of these there are five, not including the
station at Clermont, in consequence of its great elevation: they are
as follows:—
° ′ ″
Dunkirk 51 02 10; its pendulum at the level of the sea = 39.13771
Paris 48 50 14; " " " " 39.12894
Bordeau 44 50 26; " " " " 39.11295
Figeac 44 36 45; " " " " 39.11212
Formentera 38 39 56; " " " " 39.09176
The mean length of the seconds pendulum at the level of the sea, in
the latitude of 45° 14′ 10″, deduced from these determinations, is
39.1154; and it is so equally, whether an ellipticity of 1/288th,
or of 1/304th, or any intermediate ellipticity, be assumed in the
reduction.
We have, then, 39.1154−39.0992 = ·0162 inch., as the [p158] measure
of the difference in the intensity of gravitation at the place of
observation elevated 1943 metres; and at the level of the sea. The
radius of the earth, being 6,376,478 metres, this measure, according
to the duplicate proportion of the distances from the earth’s centre,
should be ·0238 inch. The attraction of the mountain is, then,
equal to ·0238−·0162 = ·0076 inch. Whence it appears that, in this
particular instance, the correction for the elevation is reduced,
by the attraction of the interposed matter, 68/100ths, or to about
7/10ths of the amount immediately deducible from the squares of the
distances.
It is obvious that, if we possessed a correct knowledge of the
density and arrangement of the materials of which Mont Cenis is
composed, so as to enable a computation of the sum of all the
attractions which they exercise on the place of observation, this
result might furnish, as well as Dr. Maskelyne’s experiments on the
deviation of the plumb-line produced by the attraction of Mount
Schehallien, a certain determination of the mean density of the
earth. Professor Carlini considers that the form of the eminence may
be sufficiently represented by a segment of a sphere, a geographical
mile in height, having as its base a circle of 11 miles diameter,
the distance from Susa to Lansleburgo; the attractive force, on
a point placed on the summit, would, in such case, be equal to
2 π δ (1 − (2/3) √(1/11)) or in numbers to 5·020 δ, δ being the
density of the mountain, and 2 π the ratio of the circumference to
radius. The attractive force of the earth, on a point at its surface,
is (4/3) π r Δ, = 14394 Δ, _r_ being the radius of the earth = 3437
geographical miles, and Δ its mean density. Now these two quantities,
14394 Δ and 5·020 δ, should be, to each other, in the proportion
of 39.1154,—the pendulum at the level of the sea, representing
gravitation at the surface of the earth,—to ·0076, the portion of
gravitation at the summit of the mountain due to the attraction
of the mountain. By the observations of M. de Saussure and other
geologists, Mont Cenis is chiefly composed of schistus, marble, and
gypsum; the specific gravities of which substances were ascertained,
from numerous specimens in the possession of M. Carlini, to be
respectively as follows:— [p159]
The schistous 2·81.
The marble 2·86.
The gypsum 2.32.
In the absence of a precise knowledge of the quantity and position
or each of these three component parts, we may take the mean, 2.66,
of their several densities as approximatively the density of the
mountain, = δ. We have then
5.02 δ × 39.1154
Δ = -------------- = 4.77,
14394 × ·0076
a result differing little from that of Cavendish as recently
corrected by Dr. Hutton, and still less from that of the Schehallien
experiments.
The most hypothetical element of this calculation is the width
assigned to the base of the mountain; but by the very nature of the
question, it has but little influence on the final result; since,
by even doubling the assigned diameter, the total attraction would
not be altered a twentieth. In regard to the mean density of the
mountain, if it were taken at 2.75, instead of 2.66, that of the
earth would result 4.94, instead of 4.77, as given above.
E. S.
_Transactions of the Horticultural Society_. Vol. vii. Part 1. 4to.
London, 1827. pp. 208.
I. _Observations upon the Growth of Early and Late Grapes under
Glass_. By Mr. James Acon.
Few gardens are to be found in which bunches of fresh ripe grapes can
be gathered every day in the year: notwithstanding the importance
of the fruit to the luxurious, and the facility with which the vine
submits to the artificial climate of the forcing-house. Nothing is
easier than to secure crops of grapes in a vinery during the spring
and summer months; but it is far more difficult to obtain them in
the last and earliest seasons of the year, when the plants would
[p160] naturally be in state of torpidity. It is well known that
this desirable purpose is attained in great perfection in the garden
of the Earl of Surrey, at Worksop Manor; and the management there
practised is the subject of this paper.
The common methods of forcing early grapes are to train the vines
under the roof near the glass, or on small frames against flued
walls; but to both these practices Mr. Acon finds great objections:
to the former because it renders the house too dark, and exposes the
young and tender branches to the pernicious effect of blasts of cold
air rushing through the interstices of the panes; and to the latter,
because the heat of the flues is apt to scorch the branches, and
in consequence to destroy the crop,—excessive heat in the one case
producing the same injurious effects as excessive cold in the other.
The following are the two modes by which Mr. Acon obtains his _very
early_ and his _very late_ grapes. For the early crops a house is
used, of which the back wall is 9.6 feet in height, and the front
wall 3 feet, the roof forming an angle of about 30 degrees. It is
heated, from the absolute necessity of employing an atmosphere of
unusually high temperature, with two flues that pass along the middle
of the house, and return in the back wall; a fire-place being built
at each end of the house. Forcing begins on the first of September,
and the fruit begins to ripen the first week in March. The vines
are trained upon a trellis, fixed over the flues, in the centre of
the house, and also upon the back wall; but none are allowed to
obstruct the light by occupying the roof, until about six weeks after
the forcing has commenced, when some new shoots are introduced and
trained to the rafters. The form of this house gives it a peculiar
advantage, in presenting a greater surface for the growth of vines
than can be derived from any other plan; the trellis which is placed
over the flues is nearly equal to the whole roof, without being in
any degree injurious to the plants trained upon the back wall. The
vines are planted in the inside of the house, but in such a manner
that the mould in which they grow is not heated by the fire-places
of either flue. The usual mode of exposing the main stem of a forced
vine to an extremely low temperature in the external air, while the
branches are stimulated by a very high temperature in an entirely
different atmosphere, is very properly objected to. Nothing, in
fact, can be more injudicious than such a practice, in cases where
very early forcing is required; for it should be borne in mind,
that although the absorption of the elements by which the proper
juices of a [p161] plant are elaborated, and brought into the state
under which they appear in the fruit, and in the secretions of the
plant, is carried on by the leaves alone, yet that all these juices
have, in the first instance, to pass along the vessels of the stem
before they reach the leaves; and that the whole of the bark of a
tree is, rightly considered, a leaf of a particular description,
formed of the same kind of tissue, and exercising the same functions,
and undoubtedly producing a powerful effect upon the motion of the
fluids of the branches, with the vessels of which it is elaborately
and intimately entangled, from the core to the circumference. No
argument can be necessary to show that an equal action of the vessels
of a plant is indispensable to the due maintenance of the vegetable
functions in a healthy state, and that this is not to be maintained
by exposing the main stem and the extremities to an atmosphere and
temperature entirely different. Such irregularities do not exist in
free Nature, and she will not submit to them when in fetters.
In pruning vines for early forcing, as little wood should be employed
as possible. Mr. Acon stops the shoots one joint above each cluster,
and has no joint without a bunch. When the crop is over, and the wood
perfectly matured, the branches should be laid near the ground, and
shaded till the recommencement of forcing. In short, they should be
placed in a condition as nearly as possible resembling the gloom and
cold of winter. If this process be well managed, the vines will alter
their natural habits, and instead of budding with the spring, their
vegetation will naturally commence at the period at which they have
been accustomed to be stimulated.
For late grapes, a house of a different construction is employed.
The back wall is 12 feet high, the front wall 1-1/2 foot, and the
roof lies at an angle of 45 degrees. The heat is supplied by a single
flue passing along the middle of the house. The sorts best adapted
for late forcing are the Muscat of Alexandria, the St. Peter’s, and
the Black Damascus; all other kinds wither prematurely. This house
is generally shut about the middle or end of May, as soon as the
bunches become visible. The vines are trained on a trellis near the
glass. Till they are out of blossom the air is kept very warm, a
point to which much importance attaches, because it is during this
period that all the branches that are to bear fruit in the succeeding
season are produced. In a high temperature, the branches will grow
more compactly, and [p162] will be more regularly matured than in
a low temperature, in which the wood is apt to become excessively
luxuriant, and not to ripen well. Great attention must be paid to
this point. As much air as possible is introduced into the vinery
during the summer; but as the autumn advances, more caution in this
respect is observed. The fruit should be perfectly coloured at the
approach of the dark season; for if the colouring be deferred too
long, the berries will never acquire their proper flavour. Great
care must be observed to remove daily such berries as are inclining
to damp, or the whole crop will soon be spoiled. This should be
particularly attended to; for the contagion of what gardeners call
_damp_, arises from the growth of minute fungi which vegetate upon
the epidermis, and spread during the autumn with alarming rapidity
from bunch to bunch.
The pruning of vines for late forcing is the same as has been already
explained. When the crop is gathered, the house is unroofed for a
short time, in order to expose the branches to a low temperature,
and to the degree of humidity necessary to replenish their vessels,
which have been drained by the dryness of the climate in which, when
forced, they were necessarily kept.
By the means above described, a regular supply of grapes is secured
through the year. The late-house crop lasts from the middle of
January to the end of March; it is succeeded by the first crop in
the early-house, which carries on the supply into May, and it is
continued by the grapes on the rafters in the same house until the
vines in the pine stoves, which are forced early in January and
February, produce their crops. These continue bearing through the
summer, when a vinery, of which the forcing commences about the end
of March, furnishes the supply till the late-house fruit is ready in
January.
Upon the whole this may be considered a most instructive and valuable
communication.
II. _On the Varieties of Cardoon, and the Methods of cultivating
them_. By Mr. A. Mathews.
Who does not wish to read of the cardoon; of that prince of
vegetables, whose praises have been sung or said by all cooks and
gourmands, from the fastidious Périgords and Cardellis of the
French _cuisine_, down to the more homely Rundells and Glasses
of our English kitchens; whose virtues are so marvellous as to
be credible upon no less authority [p163] than that of the sage
gastrophilists aforesaid. To restore unwonted vigour to old age,
and new elasticity to youth, are the most modest of its attributes;
the magical broth with which the veins of Æson were replenished by
the cunning Medea, was doubtless prepared from the cardoon; and the
story itself is probably a sort of figurative record of the skill
of the fair enchantress in cooking this delicious vegetable, which
was well known to the Grecian gastronomes under the name of κακτος;
but this we throw out merely as a suggestion. Upon preparing herbs
thus potent for the table, cookery has exhausted all its skill; to
dress a cardoon is declared, by the highest authority in the art, to
be the surest test of a skilful cook; and one of those invaluable
acquirements which, to borrow the words of a writer not less
celebrated for his powers of composition than of cooking, “raises
cookery to the rank of the _sciences_, and its _professors_ to the
title of artists.” Our good forefathers, indeed, “could not find the
true manner of dressing cardoons,” and were content to eat them raw
“with vinegar and oyl, pepper and salt, all of them, or some, as
every one liketh for their delight;” which, considering that this
vegetable is both bitter and astringent in a high degree, does not
argue much for the delicacy of palate of our ancestors; little did
they dream of the savoury preparations that modern art has devised by
the aid of Espagnole, consommé, blancs, tammies, marking, masking,
and all the mysteries of the stew-pan.
Four varieties are here described, of which the Spanish cardoon is
the most common, and the cardon de Tours the best.
They are cultivated, like celery, in deep broad trenches, well
manured and watered. When the plants are nearly full-grown, which
will be about the end of October, a dry day is to be chosen for
performing the operation of blanching them, which is thus effected:—
“The leaves of each plant are carefully and lightly tied together
with strong matting, keeping the whole upright, and the ribs of
the leaves together. The plant is then bound closely round with
twisted haybands, about an inch and a half in diameter, beginning
at the root, and continuing to about two-thirds of its height. If
the plants are intended for winter store, they must be earthed up
like celery; but if to be consumed before the frosts set in, the
operation of earthing up may be omitted.” [p164]
III. _Accounts and Descriptions of the several Plants belonging
to the genus Hoya, which are cultivated in the garden of the
Horticultural Society at Chiswick_. By Mr. James Traill.
The beauty of one species of Hoya, viz., H. _carnosa_, has long
caused it to be a favourite with collectors. The object of the writer
of this paper is to call attention to such others as are known to
exist in gardens, or as are preserved in the records of the botanist.
The following species form the subject of the paper, viz.:
1 Hoya carnosa, _R. Brown_. 2 Hoya crassifolia, _Haworth_. 3 Hoya
pallida, _Lindley_. 4 Hoya Pottsii, (Tab. I.) 5 Hoya trinervis.
These five are all the species at present cultivated in gardens;
others are known to exist in the warmer regions of Asia, where they
should be assiduously sought for by travellers, as they are not only
very ornamental, but easily to be transported to Europe.
From such materials as he has been able to procure, the writer
enumerates the following as completing the genus Hoya, as far as at
present ascertained:
6 Hoya chinensis. 7 Hoya viridiflora, _R. Brown_. 8 Hoya lanceolata,
_D. Don_. 9 Hoya linearis, _D. Don_. 10 Hoya australis, _R. Brown_,
_MSS_. 11 Hoya nicobarica, _R. Brown, MSS_. 12 Hoya augustifolia.
The paper concludes with a detailed explanation of the best manner of
cultivating Hoyas.
IV. _On acclimatizing Plants at Biel, in East Lothian_. By Mr. John
Street, gardener to the Honourable Mrs. Hamilton Nesbitt.
Perhaps there is no point whatever, connected with Horticulture, of
greater interest than that which forms the subject of this paper;
it is the distant goal towards which we all are striving, but of
which, alas! we have not as yet even caught a glimpse. The gardener
is in possession of the powers by which he can bend the seasons to
his will; he can dispel the frozen gloom of winter with the rich
warm glow of the vintage; at his call the flowers of spring and
summer start up beneath his feet, and his hothouses are filled with
the luscious fruits of the torrid zone. All this he knows how to
effect with an artificial climate; but he has no influence over the
natural climate of his country, nor can he impart to the vegetation
of warmer latitudes the least additional power of resisting cold, for
which they have not been prepared by nature. Acclimatizing is still
a secret to be discovered. To [p165] this day not a single instance
can be adduced of any exotic plant whatever possessing greater powers
of withstanding cold, than it had when first introduced. It has been
hoped that if the seeds of given plant could be procured, for many
generations, in a climate severer than its own, the offspring so
obtained would gradually accommodate themselves to their new country;
but no such result has followed from the experiments that have been
tried. Let us take a few familiar examples:—the common nasturtium,
(Tropælum majus,) a native of Peru, is said to have been introduced
about the year 1686. At the time at which we are writing, it must
have descended through about 140 generations; and yet it has not
become in the smallest degree capable of resisting cold. Of the
mignonette (Reseda odorata), the date of introduction is not well
ascertained; it has probably been a favourite border annual for sixty
or seventy years, and yet it has in no degree shaken off its annual
character, which is unnatural to it, and resumed the suffrutescent
habit which it possesses in its own milder climate. The potato,
too, which has for two centuries and a half been increased in every
conceivable manner, by seeds as well as by offsets, bears cold in
no degree more readily than it did in the sixteenth century. Nor
does it appear to us probable, that acclimatizing, if practicable,
is to be brought about by sowing seeds in northern latitudes
through successive generations. We do not believe that plants will
bear their seeds at all in a temperature much lower than that in
which they have been located by the hand of Nature. The heat of a
northern summer sufficiently approximates to that of the tropics,
to be considered, with reference to vegetation, as the same, and
it is during that season that the seeds of all plants are ripened;
the conditions, therefore, under which the seeds of Tropæolum, for
example, are produced in England, do not materially differ from those
under which the same seeds are produced in Peru; if the season proves
unpropitious in any considerable degree, they are not produced at
all. How then can it be expected that seeds ripened under similar
circumstances, but in different latitudes, should give birth to a
progeny differing in any remarkable particular from their parents?
In fact, in power of resisting cold, they do not differ at all. If
such a capability were to obtained, it would be by inducing plants to
ripen their seeds in winter.
But if it is certain that nothing is to be gained in acclimatizing,
by raising plants from seed through successive generations, [p166]
it is no less true that many trees, which have been supposed to be
incapable of surviving a northern winter, are now ascertained to be
perfectly hardy, and that the power of enduring cold may be increased
in others, by a judicious management of soil and situation.
The phenomenon of vegetable life being destroyed by cold, probably
arises from the vessels, through which the circulation and secretion
of the fluids of plants take place, being ruptured by the expansion,
from cold, of the fluid they contain. In proportion, therefore,
to the tenuity of the vessels, and the abundance of their fluid,
will be the danger to which they are exposed from frost; and to the
strength of the vessels, and the paucity of their fluid, the power
of resisting cold. Thus vigorous shoots of the oak, walnut, and many
other trees, which are formed with rapidity, imperfectly matured,
and highly charged with fluid, are extremely impatient of cold, and
are even destroyed by a few degrees of frost; while the twigs and
branches of the same trees, which are formed slowly, fully matured,
and incompletely filled with fluid, bear unharmed the utmost rigour
of our winters. In acclimatizing, therefore, this law should be
carefully remembered, and the situations in which tender plants are
stationed, should be those in which their growth is restrained, and
an excessive absorption of fluid prevented.
This appears to have been the true secret of the success that has
attended the attempts at acclimatizing, which form the subject of
Mr. Street’s communication. By planting in situations well drained
from superfluous moisture, under circumstances where rapid growth
was rendered impracticable, and, as we understand, in a garden
admirably adapted to the object, from its position, he has succeeded
in naturalizing, in latitude 56° N., plants which have not yet been
known to endure the winters even of the parallel of London.
V. _Upon the Culture of Celery_. By Thomas Andrew Knight, Esq.,
F.R.S., President.
“That which can be very easily done, without the exertion of much
skill or ingenuity, is,” Mr. Knight observes, “very rarely found
to be well done, the excitement to excellence being in such cases
necessarily very feeble.” This remark is in the present case applied
to the cultivation of celery, which, being a native of the sides
of wet ditches, might naturally be expected to demand an abundant
supply of water when cultivated. Accordingly, Mr. Knight found that
by keeping the ground, in which celery was planted, [p167] constantly
wet, it grew by the middle of September to the height of five feet,
and its quality was in proportion to its size. Mr. Knight also
recommends planting at greater distances than is usually the case,
and covering the beds, into which the young seedlings are first
removed, with half-rotten dung, overspread to the depth of about two
inches with mould; under which circumstances, whenever the plants are
removed, the dung will adhere tenaciously to their roots, and it will
not be necessary to deprive the plants of any part of their leaves.
VI. _Report upon the New or Rare Plants which flowered in the Garden
of the Horticultural Society at Chiswick, between March, 1825, and
March, 1826_. Part 1. _Tender Plants_. By John Lindley, Esq.
The subject of this paper consisting of botanical details which do
not bear curtailing, we shall only extract the names of the new
species described in it, as a guide to our botanical readers. In the
whole, thirty-three species are noticed; of which the following are
published for the first time:—
2 Passiflora obscura. 7 Solanum dealbatum. 10 Tabernæmontana
gratissima. 13 Tephrosia? Chinensis. 15 Hellenia abnormis. 16
Gesneria Douglassii. 21 Gynandropsis pulchella. 23 Rodriguezia
planifolia. 26 Brassavola nodosa. 33 Phycella corusca.
VII. _Account of a Protecting Frame for Fruit-Trees on Walls_. By
Mr. John Dick.
In order to protect the fruit upon walls from the ravages of bees,
wasps, flies, and other winged enemies, a frame is contrived fitting
close to the face of the wall, and having a moveable sliding canvass
front, which can be readily removed when the fruit is to be gathered,
and replaced again afterwards. A plan of the frame accompanies the
paper. From what we have seen of this contrivance, we know that it is
well adapted to its purpose, and that no garden in which fine fruit
is required, should be without one or more of such frames. For the
mode of making them, we must refer to the paper itself.
VIII. _On the Esculent Egg-Plants_. By Mr. Andrew Mathews.
In this country, the egg-plant, brinjal, or aubergine, is chiefly
cultivated as a curiosity; but in warmer climates, where its growth
is attended with less trouble, it is a favourite article of the
kitchen-garden. In the form of fritters, or farces, or in soups, it
is frequently brought to table in all the southern parts of Europe;
and forms a pleasant [p168] variety of esculent. This paper describes
the only two kinds that are worth cultivation in England.
IX. _Notices of Communications to the Horticultural Society, between
January 1, 1824, and January 1, 1825. Extracted from the Minute
Books and Papers of the Society_.
A novel kind of pine pit is described, which is said to answer every
purpose that can be desired. It is heated by flues passing through a
chamber, formed by beams extending from the back to the front wall,
and so becoming a sort of floor, upon which is first placed a layer
of turf; and then the tan in which the pine-plants are plunged. The
warmer air is conveyed into the upper part of the pit by means of
small apertures contrived in the walls, at four inches and a half
apart, both in the back and front of the pit, and also through
iron pipes resting on the beams and passing through the tan. The
ventilation is effected by air-holes in the front wall, and sliding
shutters in the back walls. An explanatory figure accompanies the
statement.
The famous rhubarb, which has of late acquired so much celebrity
under the name of Buck’s rhubarb, is mentioned as excellent when
forced. It is not generally known, that this sort is the genuine
Rheum undulatum of botanists uncontaminated by mixture with the
common garden kinds. The plant generally called Rheum undulatum, is
a half-bred, possessing none of the good qualities of the native
species.
George Tollet, Esq., of Betley Hall, in Staffordshire, recommends
the preservation of apples for winter store, packed in banks or
hods of earth like potatoes. The method is said to be effectual and
economical.
Thomas Bond, Esq., of East Looe, in Cornwall, describes his mode of
cultivating strawberries. He does not adopt the common practice of
cutting off the runners, but they are confined to the bed by being
turned back among the plants from which they spring. In the autumn,
the beds are covered to the depth of two inches with fresh earth,
through which the strawberry plants shoot in the spring with great
vigour.
A kind of wicker basket is described, which is cheap and well adapted
for screening half hardy plants during the winter. It is fixed in the
earth by means of the points of the ribs of the wicker work, which
are allowed to project a few inches for the purpose.
It is stated by John Wedgewood, Esq., that good celery may be readily
obtained by transplanting seedling plants that have remained in the
seed bed, till they had acquired a [p169] considerable size. They
grow more vigorously than the younger plants that are transplanted in
the usual way.
William Cotton, Esq., of Wellwood-house, describes the good effects
of painting an old garden wall with seal oil and anticorrosion paint.
The wall in question was covered with trees, which were every year
attacked by blight. Since the operation the trees have borne good
fruit, made healthy wood, and been free from the bad consequences of
blight.
Mr. John Mearns states, that the red and white Antwerp raspberries
may be brought to bear abundantly in August, long after the usual
crop of raspberries is past, by the following management. In May he
removes the young fruit, bearing shoots, from the canes, leaving in
some cases one or two eyes, in others, cutting them clean off. Under
either plan, they soon produce an abundance of vigorous new shoots,
which blossom freely in July.
Mr. Elias Hildyard, gardener to Sir Thomas Frankland, kills the grub
which infests his onion beds by trenching the beds in winter, digging
in manure at the same time, and leaving them exposed to the frost in
a rough state till the time of sowing.
A mode of inducing fertility in a barren Swan’s-egg pear-tree trained
upon a wall, is described by the Rev. John Fisher, of Wavenden, in
Buckinghamshire. It consists in twisting and breaking down the side
shoots of the main branches in such a way, as to make them pendulous
without separating them wholly from the parent limb. In a short time
a grumous formation takes place where the fracture has occurred, the
wound heals, the flow of the sap is moderated, and fruit buds are
formed instead of sterile shoots.
Mr. William Mowbray, gardener to the Earl of Mountnorris, states,
that the different species of eatable Passifloras which do not
generally produce fruit, may be induced to do so abundantly, if the
pollen of other species is applied to their stigmas.
Currants are preserved in perfection in the garden of James Webster,
Esq., of Westham, by being covered with bunting when the fruit is
fully ripe, care being had to unloose the bunting occasionally from
the bottom of the bushes, in order to remove the decaying fallen
leaves.
X. _Report on the Instruments employed in, and on the Plan of a
Journal of Meteorological Observations, kept in the garden of the
Horticultural Society at Chiswick_.
This and the following paper we propose to notice in detail on a
future occasion. [p170]
XI. _Journal of Meteorological Observations made in the garden of
the Horticultural Society at Chiswick, during the year 1826_. By Mr.
William Beattie Booth.
XII. _On Orache, its Varieties and Cultivation_. By Mr. William
Townshend.
The herb orache was formerly cultivated as a kind of summer spinach;
but in this country it has long been expelled from the kitchen garden
by other kinds. It is, however, still seen in the gardens of France,
where it is commonly called Arroche des jardins, being used in that
country, both by itself as a spinach, and mixed with sorrel, the
acidity of which it corrects. Seven varieties are described, which do
not differ in their qualities, but are distinguished by the colour of
their foliage.
XIII. _On planting the moist Alluvial Banks of Rivers with
Fruit-Trees_. By Mr. John Robertson.
The object of this writer is to show that the low grounds that form
the banks of rivers are, of all others, the best adapted for the
growth of fruit trees; the alluvial soil of which they are composed,
being an intermixture of the richest and most soluble parts of the
neighbouring lands, with a portion of animal and vegetable matter,
affording an inexhaustible fund of nourishment. In such situations,
however, the trees are liable to injury from floods in the winter,
unless some means are used of draining off the stagnant water. This
is to be effected by digging deep trenches between the rows of trees,
casting up the earth from the trenches around the trees on either
side, so as to form elevated banks. Such is the practice in Holland,
where the western slopes of the dykes are generally covered with
fruit-trees, chiefly apples and pears. Mr. Robertson is of opinion,
that the banks should be raised, if possible, at least three or four
feet above the highest water-mark, and be made eighteen feet broad
at the base, and twelve at top; the trenches should be fifteen or
sixteen feet wide, admitting the soil to be three or four feet deep.
Upon this plan, it is probable that abundant crops would be obtained;
but with regard to the quality of the produce, we suspect it will be
quite as indifferent as the apples and pears of the Dutch, which are
notorious for their want of flavour.
XIV. _On Dahlias_. By Mr. William Smith.
This is an attempt to distinguish by words the best varieties of
the Dahlia, and to fix the names of those which are the most worthy
of cultivation. Sixty kinds are well described, [p171] arranged in
divisions depending upon the size of the plants and the colour of
their flowers. We do not propose to analyze this paper, which is far
too extensive for our limits; but instead, to throw together a few
remarks which are suggested by the subject.
The first fact to which we would call attention has reference to
acclimatization. The Dahlia has now been cultivated in Europe with
the utmost assiduity for nearly thirty years. During that period
millions of plants have been raised from seeds, and under almost
every possible variation of climate; and anomalies the most singular,
not only in colour, but in general constitution and physiological
structure, have been obtained. The colour of the flower has been
altered from pale yellow, or lilac, to every hue of red, purple,
or yellow, to pure scarlet and to deepest morone, or has even been
wholly discharged from the radial florets in the white varieties; the
period of flowering has been accelerated nearly two months; the tall
rank weed, exceeding the human standard in height, has been reduced
to a trim bush, emulating the pæony in dwarfishness; the yellow
inconspicuous florets of the disk have been expelled to make room for
the showy deep-coloured florets of the ray; what is more remarkable
still, the same yellow inconspicuous florets of the disk have been
enlarged, and stained with rich morone, so as to rival the colours of
the ray without losing their own peculiarity of form; and finally,
the whole foliage and bearing of the plant has been altered by the
substitution of simple leaves for compound ones. But notwithstanding
all this proneness to change, notwithstanding the multitude of
varieties which have been thus procured by seed, _not one individual
has yet been discovered, in any degree whatever, more hardy than its
ancestors_. The earliest frosts destroyed the Dahlias as certainly in
1826, as they could have done in 1789.
But, however strong may be the disposition of the Dahlia to vary
from its original structure, it is curious to observe how strictly
it conforms to the laws by which such variations are controlled
by nature. In altered structure all the changes take place from
circumference to centre. The florets of the ray displace those of the
disk, but the latter never attempt to occupy the ray; when a change
occurs among the florets of the disk, they merely dilate and assume
the colour of the ray, without changing their position or their
peculiar form. So with the leaves; by a reduction of the lateral
leaflet, till the terminal one only remains, simple foliage is
substituted for that which was compound: but no case has been found
in [p172] which the suppression of the terminal leaflet has taken
place and the lateral ones have been preserved. In change of colour,
too, there is a circumstance which demands consideration, and of
which no explanation has yet been offered. It is not generally known,
although long ago noticed by M. De Candolle, that among flowers,
yellows will not produce blues, nor blues yellows, although both
these primitive colours will sport into almost every other hue. Thus
the hyacinth, the natural colour of which is blue, will not produce
a yellow, for the dull, half-green flowers called yellow hyacinths,
are, in our judgment, whites approaching green; the blue crocus will
not vary into yellow, nor the yellow into blue; and the ranunculus
and the dahlia, the natural colour of both which, notwithstanding
the popular belief to the contrary, with respect to the dahlia, is,
we believe, yellow, although they are the most sportive of all the
flowers of the gardens, varying from pink to scarlet, and deepest
shades of purple, have never yet been seen to exhibit any disposition
to become blue. This subject offers a most amusing field for
investigation, and would well repay the attentive consideration of
the philosopher.
XV. _On the Cultivation of Camellias in an open Border_. By Mr.
Joseph Harrison.
Mr. H. finds that the double red camellia, the double white, and
the double striped, will bear an English winter if planted out when
about two feet high, having been previously stunted in their growth
by repeatedly stopping their leading shoots. For two winters the
young plants are to be protected by a wooden screen fixed round
them, and covered by a hand-glass, the whole being enveloped in
mats; afterwards they require no other protection than to be guarded
from heavy snowstorms, and to be assisted by a thick covering of old
tan upon the ground in which they grow, to the distance of two or
three feet from their stems. If this success has been met with in
Yorkshire, what may not be expected in our more southern counties!
On the 12th of March of the present year these camellias were not
injured by a frost which did considerable damage to the common laurel.
XVI. _A Method of growing Crops of Melons on open Borders_. By Mr.
William Greenshields.
The sorts fitted for this purpose are the black rock, scarlet rock,
green-fleshed, netted and early Cantaloup melons. The method consists
of forming a bed, by half filling a shallow [p173] trench with
decayed vegetables, and covering them with the exhausted linings
of cucumber beds. The young plants are reared for some time under
handlights. For full particulars of this practice, we must refer to
the paper itself, which is clearly written, and, coming as it does
from one of our most skilful gardeners, well worthy of attention.
XVII. _Notice of Five Varieties of Pears received from Jersey in the
year 1826_. By John Lindley, Esq.
The fruits here described are of the highest excellence. They are,
1. the Marie Louise; 2. the Duchesse d’Angoulême; 3. the Doyenné
gris; 4. the Doyenné panaché; 5. the Beurré d’Aremberg; and 6. the
Gloux morceaux. The second, the fifth, and the sixth kinds are
represented in two very beautiful coloured plates; and are, perhaps,
the most exquisitely flavoured of all the varieties of the pear. The
Beurré d’Aremberg and Gloux morceaux are long keepers; the others
are autumnal kinds. Of the former it is said, “the flesh is whitish,
firm, very juicy, dissolves in the mouth, and is wholly destitute of
grittiness; it is sweet, rich, and so peculiarly high flavoured, that
I know no pear that can be compared with it in that respect.”
XVIII. _Upon the Culture of the Prunus Pseudo-cerasus, or Chinese
Cherry_. By Thomas Andrew Knight, Esq.
This species of cherry is expected to become an acquisition of
considerable value, for the purpose of forcing; and also as an early
fruit, when trained upon an open wall. Mr. Knight recommends its
propagation by cuttings, which root freely, and that it be abundantly
supplied with liquid manure. From its highly excitable habits, he
suspects it to be a native of a cold climate, probably of Tartary.
XIX. _On the Culture of the Pine-Apple_. By Mr. James Dall.
XX. _On forcing Asparagus_. By the same.
These two papers were communicated by the Cambridge Horticultural
Society, having gained one of the annual silver medals presented
by the London to Provincial Societies. They contain good practical
directions for the cultivation upon which they treat.
XXI. _Observations upon forcing Garden Rhubarb_. By Mr. William
Stothard.
This plan is perhaps the best that can be followed, as it is at once
the most certain and the most simple. You sow rhubarb seed on a rich
moist border in the beginning of April, [p174] The young plants are
well thinned during the summer; in the end of October they are very
carefully transplanted into forcing-pots, five or six in each pot.
They are placed in a north aspect, to recover the effect of their
removal from the seed-bed, and in a month they are fit for forcing.
We can safely recommend this method.
XXII. _Account of some remarkable Holly Hedges and Trees in
Scotland_. By Joseph Sabine, Esq.
This is in elaborate account of extraordinary specimens of hollies,
and appears to have been written with a view to induce the more
general cultivation in this country of that very valuable tree. At
Tynningham, the residence of the Earl of Harrington, are hedges
extending to no less a distance than 2952 yards, in some cases
thirteen feet broad, and twenty-five feet high. The age of these
hedges is something more than a century. At the same place are
individual trees of a size quite unknown in these southern districts.
One tree measured five feet three inches in circumference at three
feet from the ground; the stem is clear of branches to the height
of fourteen feet, and the total height of the tree is fifty-four
feet. The other places at which the hollies are of unusual size,
are Colinton-house the seat of Sir William Forbes; Moredun, the
seat of David Anderson, Esq.; Hopetoun-house, the seat of the Earl
of Hopetoun, and Gordon-castle, where are several large groups of
hollies, apparently planted by the hand of Nature.
XXIII. _An Account of a Plan of Heating Stoves by means of Hot
Water, employed in the Garden of_ Anthony Bacon, Esq.
We conceive that a new æra in horticulture will commence with the
publication of this paper. We already possessed contrivances of a
sufficiently good kind for all purposes connected with artificial
climate, except the power of commanding heat; for which the two
methods hitherto employed have been either too clumsy or too costly,
and in either case liable to numerous objections. The old mode of
introducing heat into a stove, by means of brick flues, has long been
considered so bad, that every scheme that promised to supersede such
flues has been hailed with joy; the uncertainty of the quantity of
heat given out by a brick flue, its continual liability to explosion,
the impossibility of preventing the escape of smoke from between the
joints of the bricks, are all evils that require a remedy. For this
purpose steam was introduced, and with great advantage in extensive
ranges of hothouses. But the enormous expense of erecting a steam
[p175] apparatus, the danger attending its use in the charge of an
unskilful or careless gardener, and also the rapid loss of heat
from the pipes upon any neglect of the boiler, have all contributed
to prevent the use of steam becoming very general. The plan now
described has the great merit of possessing all the good qualities
of steam, without any of its objectionable accompaniments; its cost
cannot in any considerable degree exceed that of flues, and its
effects are so certain and durable, that a house so heated may be
almost said to be beyond the power of neglect on the part of the
gardener.
Without entering into the details of this plan, for which we must
refer to the paper itself, we shall content ourselves with explaining
its principle. Suppose two iron reservoirs, A and B, of equal
capacity, placed twenty feet apart, and connected at the top and the
bottom by iron pipes, the level of both reservoirs being the same;
it is obvious that water poured into one of these reservoirs will
flow into the other through the connecting pipes, and that it will
consequently stand at the same height in both. Let the reservoirs
be thus filled above the level of the uppermost pipe, and heat be
applied to the bottom of one reservoir, A; the water in this will
presently be forced through the upper pipe into the reservoir, B, of
water not heated; in proportion as the heated water flows out of A,
through the upper pipe, the cold water will flow out of B through
the lower pipe; and by this means a circulation of water heated and
water to be heated will be formed, which will continue as long as the
application of fire to the bottom of one reservoir is continued. When
it is discontinued, the temperature of the two reservoirs and of the
intermediate pipes will be the same within three or four degrees.
As it is the property of heated water to part with its heat very
slowly, it follows that heat will continue to be disengaged from the
reservoirs and pipes long after the application of fire has ceased.
In fact, when the two reservoirs are once heated, the gardener may
make up his fires and retire to rest, certain that his house is
sufficiently provided with heat for the night.
The paper is accompanied with a plan of a vinery warmed upon this
principle. [p176]
_On the Recent Elucidations of early Egyptian History_.
Since the commencement of the present century, the researches of
philologists have ascertained that the language of ancient Egypt,—the
language of the hieroglyphical inscriptions engraven on its ancient
temples and monuments, and of the still existing manuscripts of the
same period,—differs from the modern Egyptian or Coptic, only in the
mixture in the latter of many Greek and Arabian and a smaller portion
of Latin words, introduced during the successive dominion of the
Greeks, the Romans, and the Arabs, and occasionally substituted for
the corresponding native words. The grammatical construction of the
language has remained the same at all periods of its employment: and
it finally ceased to be a spoken language towards the middle of the
seventeenth century, when it was replaced by the Arabian.
In writing their language, the ancient Egyptians employed
three different kinds of characters. First, _figurative_; or
representations of the objects themselves. Second, _symbolic_; or
representations of certain physical or material objects, expressing
metaphorically, or conventionally, certain ideas; such as, a
people obedient to their king, figured, metaphorically, by a bee;
the universe, conventionally, by a beetle. Third, _phonetic_, or
representative of sounds; that is to say, strictly alphabetical
characters. The phonetic signs were also portraits of physical and
material objects; and each stood for the initial sound of the word in
the Egyptian language which expressed the object pourtrayed: thus a
lion was the sound L, because a lion was called Labo; and a hand a T,
because a hand was called Tot. The form in which these objects were
presented, when employed as phonetic characters, was conventional,
and _definite_ to distinguish them from the same objects used either
figuratively or symbolically; thus, the conventional form of the
phonetic T was the hand open and outstretched; in any other form
the hand would either be a figurative, or a symbolic sign. The
number of distinct characters employed as phonetic signs appears to
have been about 120; consequently many were homophones, or having
the same signification. The three kinds of characters were used
indiscriminately in the same writing, [p177] and occasionally in the
composition of the same word. The formal Egyptian writing, therefore,
such as we see it still existing on the monuments of the country, was
a series of portraits of physical and material objects, of which a
small proportion had a symbolic meaning, a still smaller proportion a
figurative meaning, but the great body were phonetic or alphabetical
signs: and to these portraits, sculptured or painted with sufficient
fidelity to leave no doubt of the object represented, the name of
hieroglyphics, or sacred characters, has been attached from their
earliest historic notice.
The manuscripts of the same ancient period make us acquainted with
two other forms of writing practised by the ancient Egyptians, both
apparently distinct from the hieroglyphic, but which, on careful
examination, are found to be its immediate derivatives; every
hieroglyphic having its corresponding sign in the _hieratic_, or
writing of the priests, in which the funeral rituals, forming a
large portion of the manuscripts, are principally composed; and in
the _demotic_, called also the _enchorial_, which was employed for
all more ordinary and popular usages. The characters of the hieratic
are for the most part obvious running imitations, or abridgments
of the corresponding hieroglyphics; but in the demotic, which is
still further removed from the original type, the derivation is less
frequently and less obviously traceable. In the hieratic, fewer
figurative or symbolic signs are employed than in the hieroglyphic;
their absence being supplied by means of the phonetic or alphabetical
characters, the words being spelt instead of figured; and this is
still more the case in the demotic, which is, in consequence, almost
entirely alphabetical.
After the conversion of the Egyptians to Christianity, the ancient
mode of writing their language fell into disuse; and an alphabet was
adopted in substitution, consisting of the twenty-five Greek letters,
with six additional signs expressing articulations and aspirations
unknown to the Greeks, the characters for which were retained from
the demotic. This is the Coptic alphabet, in which the Egyptian
appears as a written language in the Coptic books and manuscripts
preserved in our libraries; and in which, consequently, the language
of the inscriptions on the monuments may be studied. [p178]
The original mode in which the language was written having thus
fallen into disuse, it happened, at length, that the signification
of the characters, and even the nature of the system of writing
which they formed, became entirely lost; such notices on the subject
as existed in the early historians being either too imperfect,
or appearing too vague, to furnish a clue, although frequently
and carefully studied for the purpose. The repossession of this
knowledge will form, in literary history, one of the most remarkable
distinctions, if not the principal, of the age in which we live.
It is due primarily to the discovery by the French, during their
possession of Egypt, of the since well-known monument called the
Rosetta Stone, which, on their defeat and expulsion by the British
troops, remained in the hands of the victors, was conveyed to
England, and deposited in the British Museum. On this monument
the same inscription is repeated in the Greek and in the Egyptian
language, being written in the latter both in hieroglyphics and
in the demotic or enchorial character. The words Ptolemy and
Cleopatra, written in hieroglyphics, and recognized by means of
the corresponding Greek of the Rosetta inscription, and by a Greek
inscription on the base of an obelisk at Philæ, gave the phonetic
characters of the letters which form those words: by their means the
names were discovered, in hieroglyphic writing, on other monuments of
all the Grecian kings and Grecian queens of Egypt, and of fourteen
of the Roman emperors ending with Commodus; and by the comparison
of these names one with another, the value of all the phonetic
characters was finally ascertained.
The hieroglyphic alphabet thus made out has been subsequently
applied to the elucidation of the earlier periods of Egyptian
history, particularly in tracing the reigns and the succession of
the Pharaohs, those native princes who governed Egypt at the period
of its splendour; when its monarchy was the most powerful among the
nations of the earth; its people the most advanced in learning, and
in the cultivation of the arts and sciences; and which has left, as
its memorials, constructions more nearly approaching to imperishable,
than any other of the works of man, which have been the wonder of
every succeeding people, and which are now serving to re-establish,
at the expiration of above 3000 years, the details of [p179] its
long-forgotten history. To trace these stupendous monuments of art
to their respective founders, and thus to fix, approximatively, at
least, the epoch of their first existence, is a consequence of the
restoration of the knowledge of the alphabet and the language of the
inscriptions engraven on them. We propose to review, briefly as our
limits require, the principal and most important facts that have thus
recently been made known in regard to those early times; and shall
deem ourselves most fortunate if we can impart to our readers but
a small portion of the interest which we have ourselves derived in
watching their progressive discovery.
The following are the authors to whom we are chiefly indebted for
the few particulars we know of early Egyptian history. Herodotus
and Diodorus Siculus, Grecians, and foreigners in Egypt. Manetho, a
native; and Eratosthenes, by birth a Cyrenean, a province bordering
on Egypt, both residents. Josephus, a Jew, and Africanus, Eusebius,
and Syncellus, Christians, Greek authors. Herodotus visited Egypt
four centuries and a half before Christ, and within a century after
its conquest by the Persians. In his relation of the affairs of
the Greeks and Persians, he has introduced incidentally a sketch
of the early history of Egypt, such as he learnt it from popular
tradition, and from information obtained from the priests. It is,
however, merely a sketch, particularly of the earlier times; and
is further recorded by Josephus to have been censured by Manetho
for its incorrectness. Diodorus is also understood to have visited
Egypt about half a century before Christ; and from him we have a
similar sketch to that of Herodotus; a record of the names of the
most distinguished kings, and for what they were distinguished;
but with intervals, of many generations and of uncertain duration,
passed without notice. Manetho was a priest of Heliopolis in Lower
Egypt, a city of the first rank amongst the sacred cities of ancient
Egypt, and long the resort of foreigners as the seat of learning
and knowledge. He lived in the reign of Ptolemy Philadelphus, two
centuries and a half before Christ, and wrote, by order of that
prince, the history of his own country in the Greek language,
translating it, as he states himself, out of the sacred records.
His work is, most unfortunately, lost; but the fragments which have
been preserved to us, by the writings [p180] of Josephus in the
first century of the Christian æra, and by the Greek authors above
named of the third and fourth centuries, contain matter, which, if
entitled to confidence, is of the highest historical value, _viz._,
a chronological list of the successive rulers of Egypt, from the
first foundation of monarchy, to Alexander of Macedon, who succeeded
the Persians. This list is divided into thirty dynasties, not all of
separate families; a memorable reign appearing in some instances to
commence a new dynasty, although happening in the regular succession.
It originally contained the length of reign as well as the name
of every king; but in consequence of successive transcriptions,
variations have crept in, and some few omissions also occur in
the record, as it has reached us through the medium of different
authors. The chronology of Manetho, adopted with confidence by some,
and rejected with equal confidence by others,—his name and his
information not being even noticed by some of the modern systematic
writers on Egyptian history,—has received the most unquestionable
and decisive testimony of its general fidelity by the interpretation
of the hieroglyphic inscriptions on the existing monuments: so much
so, that by the accordance of the facts attested by these monuments
with the record of the historian, we have reason to expect the entire
restoration of the annals of the Egyptian monarchy antecedent to the
Persian conquest, and which, indeed, is already accomplished in part.
Before we pursue this part of our subject, we must conclude our
brief review of the original authorities in early Egyptian history,
by a notice of Eratosthenes. He was keeper of the Alexandrian
library in the reign of Ptolemy Evergetes, the successor to Ptolemy
Philadelphus, under whose reign Manetho wrote. Amongst the few
fragments of his works, which have reached us transmitted through
the Greek historians, is a catalogue of thirty-eight kings of
Thebes, commencing with Menes, (who is mentioned by the other
authorities also as the first monarch of Egypt,) and occupying by
their successive reigns 1055 years. These names are stated to have
been compiled from original records existing at Thebes, which city
Eratosthenes visited expressly to consult them. The names of the two
first kings in his catalogue are the same with the names of the two
first kings of the first dynasty of Manetho; but the [p181] remainder
of the catalogue presents no further accordance, either in the names
or in the duration of the reigns.
To return to Manetho:—amongst the monarchs of the original Egyptian
race there was one named by him Amenophis, (the eighth king of the
eighteenth dynasty,) of whom it is stated, in a note of Manetho’s
preserved by Syncellus, that he was the Egyptian king whom the Greeks
called Memnon. The statue of Memnon at Thebes, celebrated through
all antiquity for the melodious sounds which it was said to render
at sunrise, is identified in the present day by a multitude of Greek
inscriptions; one of which, in particular, records the attestation of
Publius Balbinus, who visited the ruins of Thebes in the suite of the
empress the wife of Adrian, to his having himself heard the “divine
sounds of Memnon or Phamenoph;” which latter name is Amenophis, with
the Egyptian masculine article φ prefixed, and omitting the Greek
termination. The hieroglyphics carved on the statue, and coeval
with its date, had been very carefully copied by the French whilst
in possession of Egypt, and were engraved in the splendid work, the
_Description de l’Egypte_, to which their researches had given rise.
These hieroglyphics contain the alphabetic characters Amnf (being the
initial vowel and all the consonants of the name Amenof) inclosed
within a ring; a distinction which had been previously observed to
take place with the names of the Roman emperors, and of the Grecian
kings and queens; and as the rings have hitherto been found to occur
in no other instance whatsoever than when containing the names and
titles of sovereigns, they are regarded as characteristic signs.
It should be remarked, that in the hieroglyphic writing, as in the
languages of other eastern nations most nearly connected with Egypt,
the vowels are often omitted, and when expressed, have not always a
fixed sound. The coincidence of the reading of the hieroglyphic name
with that recorded by Manetho, and with the Greek inscription on
the statue itself, was so far confirmatory of Manetho’s authority;
it was also highly interesting in the evidence it afforded of the
employment of the same hieroglyphic alphabet, that was in after
use in the times of the Ptolemies and the Cæsars, even in the very
early periods of the Egyptian monarchy; for the reign of Amenophis
was in the dynasty preceding that of Sesostris: it also indicated
the further [p182] advantage to be gained by the application of
the alphabet in decyphering other proper names, distinguished by
being inclosed in rings, existing on other statues, and in the more
ancient temples generally. Considerable progress had been made
in reading these, which in several instances had been found to
correspond with the names of the kings of the same and of subsequent
dynasties to Amenophis, as given by Manetho, when a most important
discovery was made of the existence of a genealogical record, in
hieroglyphics, of the titles of thirty-nine kings anterior to
Sesostris, chronologically arranged. We have already noticed that the
names and _titles_ of kings were distinguished by being inclosed in
rings; the ring containing the proper name being accompanied usually
by a second, inclosing certain other hieroglyphics, expressing the
title by which that particular king was designated; and it appears
probable that the kings of Egypt were distinguished by their titles
rather than by their names, since the same name recurs frequently
in different individuals, but the titles are all dissimilar; with
a single exception amongst the very many that have come under
observation, and in which the same title is common to two brothers.
The signification of the titles is yet obscure, except that they are
of the same general nature as is frequent in the East, such as “Sun
of the Universe,” &c.; but for the purpose of individualizing, the
sign is to us of the same value as the thing signified; and as other
monuments furnish the _names_ in connexion with the _titles_, we are
enabled to compare the succession evidenced by the titles with the
record of the historian, and thus to test the fidelity of the record.
The discovery of this hieroglyphic table was made by Mr. William
Banks in 1818, in excavating for the purpose of obtaining an accurate
ground-plan of the ruins of Abydus, near Thebes. On a side wall
of one of the innermost apartments, hieroglyphics were sculptured
inclosed in rings, ranged symmetrically in three horizontal rows,
each row having originally contained twenty rings, of which twelve
of the upper row, eighteen of the middle, and fourteen of the lower
row were still remaining, the others having been destroyed by the
breaking down of the wall. The hieroglyphics having been copied
and lithographed, it was speedily recognised that the rings in the
two upper rows consisted of titles only; with the exception of one
[p183] proper name, the last of the second row, since known to be
the name of the king whose title is the last in the succession, and
who was the fourth in reign and generation before Sesostris. The
third row was recognised to consist of one proper name and one title,
each repeated ten times, and alternating with each other: these are
since known to be the name and title of Sesostris, to whose reign
the construction of the table is with much probability ascribed. The
titles in the same row with that of the ancestor of Sesostris and
preceding it, have been identified on other monuments, coupled with
names which are those of the predecessors of the same king in the
list of Manetho.
It would exceed our limits, and it is not our purpose, to trace
in detail the successive steps by which the existence of each of
the kings of Manetho’s list, from the expulsion of the Phœnician
shepherds from Lower Egypt, and the consequent union of Upper and
Lower Egypt in a single monarchy, to the reign of Sesostris, has been
attested by the monuments. Suffice it to say, that the same number of
individuals as stated by Manetho, namely, eighteen, filling a space
of four centuries, are shown, by the monuments, to have reigned in
that interval, and to have borne the same relationship, as well as
succession, to each other, as is expressed by the historian: that,
of the eighteen names, eight in different parts of the list are read
on the monuments identically as in the historical record; and that
in regard to the names that are not identical, we have the testimony
of Manetho that some amongst the kings, Sesostris, for example, were
known by two and even by more names. The table of Abydus appears to
have been strictly a genealogical record; a record of generations, in
which view it is strictly accordant with the historian.
The period of the Egyptian annals on which this light has been
thrown, is precisely that which might have been selected in the
whole history of Egypt as the most desirable for such purpose.
Independently of its very high antiquity, it was the period of the
greatest splendour and power of the native Egyptian monarchy, and
of the highest (Egyptian) cultivation of the arts. The greater part
of the more ancient, and by far the most admirable in execution,
of the temples, palaces, and statues, which still attest by their
ruins their former magnificence, are the work of that age; and
the hieroglyphic inscriptions still [p184] extant on them, and
which, when not defaced by wanton injury, are almost as perfect
as when first executed, make known the reigns in which they were
respectively constructed, and frequently the purposes for which
they were designed. This is in itself no small achievement, when we
reflect that these extraordinary remains of ancient art were equally
the objects of vague wonderment in the times of the Roman emperors,
as they were in those of the generation preceding ourselves; but
that they are become to us objects of a more enlightened curiosity,
which they promise amply to repay, when the study that has already
made known their founders, shall reveal the signification of the
hieroglyphic histories, with which the walls of the palaces and
temples are covered. Already have we gained some very important
facts in regard to the condition, political and otherwise, of the
countries adjoining to Egypt at that early period. The monuments
of Nubia are covered with hieroglyphics, perfectly similar both in
form and disposition to those on the edifices at Thebes; the same
elements, the same formulæ, the same language; and the names of the
kings who elevated the most ancient amongst them, are those of the
princes who constructed the most ancient parts of the palace of
Karnac at Thebes. As far as Soleb on the Nile, 100 leagues to the
south of Philæ the extreme frontier of Egypt, are found constructions
bearing the inscriptions of an Egyptian king; evidencing that, during
the period of which we have been treating, Nubia was inhabited by
a people having the same language, the same belief, and the same
kings as Egypt. To the south of Soleb, and for more than 100 leagues
in ascending the Nile, in ancient Ethiopia, very recent travellers
have discovered the remains of temples, of the same general style
of architecture as those of Nubia and Egypt, decorated in the
same manner with hieroglyphics representing the same mythology,
and analogous to those of Egypt in the titles, and in the mode
of representing the names and titles, of the sovereigns. But the
proper names of the kings inscribed on the edifices of Ethiopia in
phonetic characters, have nothing in common with the proper names of
the Egyptian kings in the dynasties of Manetho; nor is one of the
Ethiopian names found either on the monuments of Nubia or of Egypt.
Thus there was a time when the civilized part of Ethiopia,—Meroe,
and the banks [p185] of the Nile between Dongola and Meroe,—were
inhabited by a people having language, writing, religion, and arts
similar to Egypt; but, in political dominion, independent of that
country, and ruled by kings of whom it does not appear that any
historical record whatsoever has come down to us.
The dates of the expulsion of the Phœnican shepherds from Egypt, and
of the reign of Sesostris, in years of the æra of our computation,
have been favourite subjects of discussion with chronologists:
Archbishop Usher fixed the former of these events in the year B. C.
1825; which would make the commencement of the reign of Sesostris
about B. C. 1483. The reign of Sesostris is connected with the
early Grecian chronology by the migration of Danaus, brother of
Sesostris, who, according to the Parian marbles, arrived in Greece
in 1485, which is a very few years earlier than the dates of Usher
would assign to that event. M. Champollion Figeac, brother of the M.
Champollion to whom the greater part of the discoveries made by the
interpretation of hieroglyphics are owing, himself a distinguished
chronologist, has assigned the year B.C. 1822 to the expulsion
of the Phœnicians, which Usher had placed in 1825: the date of
M. Champollion being derived from Manetho’s statement, that the
Phœnician invasion took place in the 700th year of the Sothiacal
period, _viz._, B.C. 2082, and that their dominion in Egypt continued
260 years. Historical accuracy may make it desirable, that the exact
year of the most ancient as well as of more modern events should be
determined, if it be possible: but for purposes of general interest,
and especially for comparison with the chronology of cotemporary
nations, which at that early period is in every case more unsettled
than the Egyptian, the period seems sufficiently determined. The
date before Christ 1822, pursued downwards through the dynasties
of Manetho, conducts with very close approximation to the known
period B.C. 525 of the conquest of Egypt by the Persians; and
intermediately, accords very satisfactorily with the dates, according
to the Bible chronology, of the conquest of Jerusalem in the reign of
Jeroboam by Shishak, king of Egypt, and of Tirhakah, king of Ethiopia
and Egypt, who made war against Sennacherib; these are the Sesonchis
of Manetho, and Sh.sh.n.k of hieroglyphic inscriptions on a temple at
Bubaste, and on one of the courts of the [p186] palace at Karnac,—and
the Taracus of Manetho, and T.h.r.k of hieroglyphic inscriptions
existing in Ethiopia and in Egypt[33].
In respect to the connexion of the events of the Jewish and Egyptian
histories, the period between the expulsion of the Phœnicians and the
reign of Sesostris possesses a peculiar interest, as being that of
the residence of the Israelites in Egypt, and of the Exodus. In the
history of Josephus, we have an extract from Manetho, in which this
latter event is expressly stated to have taken place under the father
of Sesostris, a king whose name, in Manetho’s list, is Amenophis,
(the third of that name,) and on the monuments Ramses. The date which
chronologists are generally agreed in assigning to the Exodus is
1491; that of the termination of the reign of Amenophis, according
to Champollion, is 1473, or, if the correction of his chronology
which we have suggested in a note be just, 1478: it is singular that
the difference of thirteen years (between 1491 and 1478) should be
precisely the duration of a very suspicious interval which Manetho
states to have taken place, after Amenophis had gone with his army
in pursuit of the Israelites; and during which interval neither the
king nor his army returned to [p187] Egypt, but are stated to have
been absent in Ethiopia. If the Exodus occurred during the reign of
any of the kings of the eighteenth dynasty, it could only have been
in the reign of the immediate predecessor of Sesostris; since his
conquests in Phœnicia, and his expeditions against the Assyrians and
Medes, must have brought him in contact with the Israelites, had they
been then residing in the Holy Land, so as at least to have caused
some mention to have been made in their history of the passages of so
great a conqueror. But presuming Amenophis, father and predecessor
of Sesostris, to have been the Pharaoh of the Exodus, the wandering
of the Israelites in the desert for forty of the fifty-five years
ascribed to the reign of Sesostris, is a sufficient explanation
of his being unnoticed in the Jewish history; whilst the fact of
that nation having been subject to the Egyptians during the reign
of Ousirei, commencing 124 years before the death of Amenophis, is
attested by the paintings on the wall of one of the chambers of the
tomb of that king, discovered by Belzoni, and with which we are so
well acquainted by means of the model exhibited in England.
Whilst recalling to recollection the peculiar physiognomy of the Jews
pourtrayed in that tomb,—and which is as characteristic of their
present physiognomy as if it had been painted in the present age,
instead of above 3000 years ago,—the equally well characterized, but
very different physiognomy of the Phœnician shepherds, represented
on the monuments of the same period, is decisive of the error of
Josephus, who imagined the Jews and the Shepherds to be the same
people. The Phœnician shepherds, long the inveterate enemy of the
Egyptians, form a leading feature as captives, in the representations
of the exploits of the monarchs who conducted the warfare against
them. These people are always painted with blue eyes and light
hair; and it is not a little curious to see assembled on the wall
of the same apartment, different races, so distinctly characterised
as the Jew, the Phœnician, the Egyptian, and the Negro; the latter
in colour, and in the outline of the features, in painting and in
sculpture, precisely as at present; all, moreover, inhabitants of
countries not very distant from each other, and at a period when not
more than twelve or thirteen centuries had passed since all these
races had descended from a single parent. In the writings which
attempt to explain from natural causes [p188] the diversity of race
amongst mankind, much power has been ascribed to the effects of time
and climate: but the facts with which we are now becoming better
acquainted than before, do not appear to admit of explanation from
those circumstances. It is worthy of notice that the negro, and the
light-haired and blue-eyed people, the two races who might be deemed
at the greatest distance apart amongst the varieties of man, are,
equally with the intermediate Egyptians, the descendants of Ham.
Of the succession of kings in Manetho’s chronology, from Sesostris to
the Persian conquest, a space of nine centuries and a half, about one
half the names have been already identified on different monuments:
four of the Persian monarchs, subsequent to the conquest, have also
been traced in inscriptions in phonetic characters; their names
are written, as nearly as can be spelt with our letters, Kamboth,
(Cambyses); Ntariousch, (Darius); Khschearscha, (Xerxes); and
Artakschessch, (Artaxerxes.)
The ascent by monumental evidence to yet more remote antiquity
than the expulsion of the Phœnician shepherds, (B.C. 1822), is not
altogether without hope, notwithstanding the general demolition of
the temples of the gods, which took place according to Manetho,
during the long dominion of the Phœnicians in Egypt. We learn from
the _Description de l’Egypte_ that even the most ancient structures
at Thebes are themselves composed of the debris of still more ancient
buildings, used as simple materials, on which previously sculptured
and painted hieroglyphics are still existing; these are doubtless the
remains of the demolished temples, but the inscriptions will require
to be studied on the spot. There is also reason to believe, that
there exists amongst the ruins of the palace of Karnac, a portion of
still more ancient construction than the palace itself; which, having
escaped demolition, was incorporated with the more recent building.
The inscriptions on this apparently very ancient ruin present the
name and title of a king, which form a very interesting subject for
future elucidation. The title does not accord with any one now extant
on the table of Abydus, but possibly may have been one of those which
were destroyed with a portion of the wall, and which are of kings
of earlier date than the expulsion of the shepherds. The name is
Mandouei, which name occurs in the dynasty anterior to Sesostris, but
coupled [p189] with a different title, an effectual distinction; nor
does the name recur in any subsequent dynasty. M. Champollion Figeac
has, with much ingenuity, shown the probability of the identity of
the Mandouei of the ancient ruin with the Osymandyas, Ousi-Mandouei,
mentioned by Diodorus Siculus as an Egyptian king greatly
distinguished by his conquests, whose reign M. Champollion infers,
from the historical passages relating to him, to have commenced 190
years before the Phœnician invasion, or B.C. 2272 years; a prodigious
antiquity, and of the very highest interest should it be established,
since there exist of this individual no less than three statues in
European collections, distinguished by the same name and title: two
of these are colossal, one at Turin, and a second at Rome: a third
is in the British Museum; and as all particulars must interest which
relate to a statue, of which there is at least probability that is
the most ancient existing in the world,—the date attributed to it
being earlier than the birth of Abraham,—we copy from Burckhardt the
following short description of its discovery: “Within the inclosure
of the interior part of the temple at Karnac, Belzoni found a statue
of a hard, large-grained sandstone: a whole length naked figure
sitting upon a chair with a ram’s head upon the knees: the face and
body entire; with plaited hair falling down to the shoulders. This
is one of the first, I should say, the first Egyptian statue I have
seen: the expression of the face is exquisite, and I believe it to be
a portrait.”—(J. L. BURCKHARDT, _Travels in Nubia_, lxxvii. _Letter
to Mr. W. Hamilton, 20th February, 1817_.)—This statue is in the
farthest corner on the right hand side after entering the gallery
of the Egyptian antiquities in the British Museum; and compared
with other statues in the same gallery, which are of kings of the
eighteenth dynasty, the dissimilarity of the features from the very
characteristic ones of the latter family is too striking to be
questioned. The problem of the age of this king Mandouei is, at all
events, a highly curious one; and will probably receive its solution
amongst the many other valuable discoveries which cannot fail to
result from M. Champollion’s projected visit to Egypt, in which
he will be accompanied by the sincere good wishes of every one in
every country, who feels an interest in the restoration of authentic
history.
E. S.
FOOTNOTE:
[33] It appears to us that a slight inaccuracy has crept into the
deduction of all the dates in M. Champollion’s Chronology subsequent
to the expulsion of the shepherds. The date of that event is the
foundation of the subsequent dates, and is supposed to have taken
place B.C. 1822; after which, according to the extract of Manetho in
Josephus cited by M. Champollion, Thoutmosis, the king by whom they
had been expelled, reigned 25 years and 4 months, followed by the
other kings of the eighteenth dynasty, making altogether 342 years
and 9 months: (including the 2 years and 2 months additional of
Horus, in compliance with the version of the passage in the Armenian
text of the Chronicle of Eusebius.) This number, 342 years and 9
months, falling short of the 348 years attributed to the eighteenth
dynasty in Eusebius and Syncellus, M. Champollion has suggested that
Thoutmosis may have reigned the five years which constitute the
difference, before the expulsion of the shepherds, since, according
to the record, he did reign, some years before that event, over
all the parts of Egypt not possessed by the shepherds. So far, so
well: but in such case, the year B.C. 1822, being the epoch of the
expulsion of the shepherds, and not of the commencement of the
eighteenth dynasty, must surely correspond to the fifth year of the
reign of Thoutmosis, and not to the first, as M. Champollion makes
it. We have hesitated to venture this remark on a matter to which M.
Champollion must have given much attention, believing that mistake
in us is much more probable than an accidental inadvertence in
him; but we have returned frequently to the consideration, without
having been able to satisfy ourselves; and the rectification of our
mistake, if it is one, may prevent others falling into the same.
[p190]
_Proceedings of the Horticultural Society_.
_June 19th_.
At this meeting a paper was read from the President, T. A. Knight,
Esq., upon the culture of the mango and cherimoyer. Its object was to
suggest some improvements in the management of these and other trees
cultivated in stoves, deduced from an application of Dutrochet’s
electrical theory of vegetation to practice. It has now become
generally known that this observer is of opinion that the motion
of the fluids in plants depends upon two currents of electricity,
setting with very unequal force between the denser fluid of the tree
and the lighter fluid of the soil in which the tree is planted; the
more powerful current setting from the latter to the former, and
so producing absorption, by conveying aqueous particles into the
roots, through the vegetable membrane of the epidermis. In applying
this theory to practical purposes, Mr. Knight recommends that the
pot in which the cherimoyer or mango is planted, should itself be
surrounded by a medium through which an equable and regular supply
of fluid may be conveyed to the roots, and that the naked surface
of the pot should by no means be exposed to the free action of the
atmosphere. Without entering upon any question of the accuracy of
the French philosopher’s observations, it is quite certain that such
a mode of cultivation is that which is most congenial to plants,
and which is indispensable to those of a habit at all delicate. The
common practice of plunging pots into a tan-bed, or among sand, if
in glass-houses, or in the earth if in open borders, is a proof of
the necessity that gardeners have found, of securing as regular a
temperature and degree of humidity as is possible for the outside of
their flower-pots; through the pores in which, moisture is chiefly
conveyed to the roots, which always cling to the inside surface of
the pot.
Specimens of roses produced by branches budded upon the Rosa indica,
were exhibited by Alexander Evelyn, Esq. We notice these not only
on account of their extraordinary beauty, but also for the sake
of recommending most strongly the adoption of the practice where
delicate roses are found difficult of cultivation _per se_. If we
consider what happens when the operation of budding, or grafting
has succeeded, the reason of the advantage derived from such an
operation will be apparent. When a bud of one variety is inserted
under the bark of another variety, a union takes place between the
cellular substance of the two; the bud is then placed in the same
[p191] situation with regard to the stock, as the seed when sown
is with regard to the earth. It immediately derives its nutriment
from the ascending sap of the new tree, and begins to form its wood
and branches, and to secrete its proper juices in proportion to the
supply of food it now receives. If a plant from any cause produces
roots with difficulty, its whole habit will be delicate, and its
flowers if formed, will, as in the case of that most lovely of
flowers, the double yellow rose, probably fall off without expanding,
from the want of an adequate supply of nutriment from its roots;
but, as in all trees, every bud is, when fully formed, in itself a
perfect and distinct individual, if such an individual be removed
from its own root, and placed where it will be supported by the
healthy vigorous roots of another species of variety, which happens
in budding, it will no longer have to depend upon a source, the
supplies from which are imperfect, but on the contrary, like a seed
removed from barren fertile ground, it will flourish in a degree
before unknown. The contrary effect takes place when a vigorous plant
is transferred to one less vigorous. And hence, the whole effect of
stocks upon the scions, or buds inserted upon them.
There was also a great variety of fruit and flowers upon the table,
and seeds of several useful vegetables were distributed.
_July 3rd_.
Seven medals were awarded to different individuals for fruit sent
by them to the Society’s fête on the 23rd of June; and one to Capt.
Drummond, for his “successful exertions in bringing living plants of
the mangosteen from the East Indies.” A paper by the president was
read upon an improvement in the mode of constructing hotbeds, but we
despair of explaining it successfully without reference to figures.
Among the display of fruits and flowers, which were exceedingly
numerous, we were particularly struck by a collection of twenty-two
varieties of strawberries from the Society’s garden.
Upon this occasion, thirty-nine new members were either ballotted
for, or proposed, a striking proof of the estimation in which the
Society is held by the public.
_July 17th_.
Upon this occasion, an enormous pine-cone from the River Columbia
was exhibited. It measured 16-1/2 inches in length, and was stated
to have been procured by the Society’s collector, Mr. David Douglas.
Its seeds were represented to be as large as those of the stone-pine,
and eatable. The tree is of the family of Pinus strobus, [p192] and
will be an invaluable acquisition to our forests, if it should prove
to succeed as well in this climate as in its own. We have already
given some account of this plant in the last number of the old series
of this Journal. The usual display was made of the finest fruit and
flowers of the season.
_August 7th_.
A complete coloured set of the costly Flora danica was placed upon
the table, having been presented by His Majesty the King of Denmark.
An improved apparatus for fumigating hothouses was exhibited by its
inventor, Mr. John Read: it consists of a brass cylinder, attached to
the orifice of a pair of bellows, and fitted up with a chimney and
draft-hole closed by a valve. The tobacco is put into the cylinder
and ignited, and the blast from the bellows expels the smoke.
The contrivance is ingenious enough, but while a hot-house fifty
feet long, may be filled with smoke in ten minutes by means of a
flower-pot, with a hole in its bottom, and a common pair of bellows,
we cannot recommend any more expensive, and certainly less efficient
apparatus.
The table was covered with a profusion of fruits and flowers.
_August 21st_.
The meeting-room this day exhibited a gratifying proof of the
excellence of the productions of our English gardens. Of _flowers_,
there were dahlias of the richest colours, and the most varied hues;
some produced by plants that retain all their ancient stature, and
others by dwarfs which seem to have lost nearly every character of
the dahlia but its beauty. Of _fruits_, there were endless varieties
of apricots, apples, pears, peaches, nectarines, grapes, pine-apples,
and melons; one of the latter, from the garden of John Fuller, Esq.,
weighed thirteen pounds. The best apricot was the Moorpark; the best
apple, the Duchess of Oldenburg, than which no princess has a fairer
bloom, the best pear the Jargonelle, the best peach the Bourdine
(forced), the best pine apple the Black Jamaica. We mention these as
a guide to our readers, in their purchases of fruit-trees; for it is
certain, that no greater service can be rendered to the public, than
to point out the means by which they may avoid encumbering themselves
with the polyonymous trash with which every nursery abounds. [p193]
MISCELLANEOUS INTELLIGENCE.
I. MECHANICAL SCIENCE.
1. _On the combined Action of a Current of Air and the Pressure of
the Atmosphere_.—The phenomena observed by M. Clement Désormes[34],
when a flat plate is opposed to air or vapour passing into the
atmosphere from an aperture in a plane surface, have been rendered
so easy of production by M. Hachette, as to be at the command of
any person in any situation. M. Hachette has also accompanied the
description of his instruments with elucidations, experiments, and
philosophical reasonings.
The first simplification by M. Hachette was to make the nozzle of
a pair of double chamber-bellows terminate in the middle of a flat
plate; he found that when the bellows were worked, effects were
produced opposite the jet of air of the kind described by M. Clement,
disks of card and other substances being drawn towards the aperture
against the direction of the current. At the same time that he
described this experiment, he also announced his having produced the
same effects by using a stream of water instead of a stream of air.
[Illustration: _Fig._ 1.]
[Illustration: _Fig._ 2.]
The apparatus was still further simplified, so as to make the stream
of air from the mouth sufficient to produce the effect. A tin tube,
A, _Fig._ 1, was soldered to the middle of a round tin plate, in
the centre of which was a small orifice, E; three or four small
projections of the tin, _f f_, were left at the edges of the plate,
to prevent the disks of paper, card, or metal, from slipping off
sideways. The figure is on a scale of one-half. Instead of the tin
plate, a piece [p194] of smooth cork may be used, and for the tin
tube, a glass tube, or one made by rolling up a piece of paper.
If the tube be held horizontally, or inclining a little upward, and a
disk of card or paper be placed loosely against the aperture in the
plate, it will be found that, on applying the mouth to the end of
the tube, and blowing air through, that the disk will not be driven
away, but actually made to apply closely to the surface of the plate;
and if turned towards the ground it will be found to remain opposite
the hole, and not to fall until the current of air is stopped. Even
a plate of tin may in this way be suspended by a current of air;
which at first would be supposed to conjoin with gravity in forcing
it to the ground. When the disk is flexible and slightly elastic, a
heavy sound, and sometimes even a shrill tone, is produced by the
vibrations of the plate.
In explanation of this experiment, M. Hachette says, “The air is
pushed from the mouth A of the tube, towards the orifice E of the
plate; it strikes the part of the disk opposed to this orifice,
and the mean pressure on that part is greater than the pressure of
the atmosphere. The blown air then takes place of that between the
plate and the disk opposed to it; it moves in this interval with a
velocity decreasing from the edges of the aperture: the elastic force
of this air decreases at the same time, so that its mean pressure
between the plate and the inner face of the disk becomes less than
the atmospheric pressure; and as this last pressure is exerted on the
whole external face of the disk H, I, this disk, subject at the same
time to the two contrary pressures on its opposing faces, obeys the
greater, and is pushed towards the plate C D.”
“It is not necessary that the disk, C D, should be near the orifice
E, of the tube A E. Let _Fig._ 2 be an instrument composed of a
hollow cylinder, C D F G, and a flat border of the dimensions C″ F,
or G D″. Let a tube, A E, be fixed to the bottom of the cylinder,
the orifice E having a diameter of about three millimeters (0.12
of inch). If air be blown in at A, against the disk, H I, in the
neighbourhood of the flat border, the disk will be urged towards
the orifice E. This instrument is also delineated on a scale of one
half. The disk, with the attached weight, weighs about 12 grammes
(184.87 grains), being 54 millimeters in diameter; the pressure of
the atmosphere upon it equals 23 kilogrammes: from which it follows
that, in this experiment, the pressure of the air blown upon the
inner surface of the disk, and the atmospheric pressure exerted on
the exterior of the same disk, only differs from each other by about
one two-thousandth part of the latter.”—_Annales de Chimie_, xxxv. 34.
FOOTNOTE:
[34] See the last volume of this Journal, p. 473.
2. _Considerations relative to Capillary Action, by_ M. Poisson.—M.
Dutrochet, whilst explaining his views relative to the cause of
vital movement in plants and animals, stated that if an animal or
vegetable membrane were formed into a bag, having a tube of [p195]
glass attached to its aperture, and were then filled with a liquid
substance, having a strong affinity for another liquid, into which
the bag was to be immersed, it would not only have the power of
absorbing the latter liquid into its pores, but also, in certain
cases, of forcing it up to the top, and even out of the glass tube
held in a vertical position. On this point, a difference of opinion
with regard to the force of capillarity took place: M. Ampère
maintaining that capillary action would raise the fluid to the top of
the tube, but not cause its expulsion; while M. Poisson maintained
that, in certain cases, the latter effect could be produced. The
latter has since then published a note, which we transcribe in part,
from the _Annales de Chimie_, xxxv. 98.
[Illustration: untitled, two vessels separated by a narrow canal]
Suppose that two different fluids, A, B, are contained in a vessel,
and separated the one from the other by a vertical division; the
heights being in an inverse ratio to the densities, so that the
points, _a_ and _b_, in the two faces of the division, and situated
in the same horizontal plane, shall support equal and opposite
pressures: suppose also that the division is pierced with one or more
holes of small diameter, or, in other words, that it is traversed by
several very narrow canals, as _a_, _b_, perpendicular to the two
faces, and which may be regarded at first as filled with air, or any
other fluid.
If the substance of the division exerts upon each of the two liquids
an action superior to the half of that which the liquid has upon
itself, each liquid will enter into the canal _a_, _b_, just as it
would rise above its ordinary level in a capillary tube of the same
size and substance. It would also be urged, by the excess of pressure
which it would exert at the extremity of the canal, against the
elasticity of the included air. When the two fluids have penetrated
the interior of _a_, _b_, the air will be pushed on both sides
in different directions by forces each of which is equal to the
primitive pressure augmented by the corresponding capillary force,
_i. e._ augmented by forces proportional, according to the known
theory of M. Laplace, to double the action of the tube on the liquid,
less the proper action of the liquid itself. It will only be in the
case when the capillary force shall be the same on both sides, that
the air, after being compressed to a certain degree, will remain at
rest: for whenever this force preponderates at one end of the canal,
the air will be driven out at the opposite end, and the liquid with
the strongest capillary attraction will entirely fill the canal.
Suppose this liquid to be A, then let us consider the forces which
will act on the portion _a_, _b_, of this liquid. At the extremity
_a_, it will be submitted to the attraction of the exterior fluid
A: at the extremity _b_, it will be attracted in the opposite
direction by the liquid B. Now the two liquids being different, their
attractions will be unequal, and we will suppose that that of B, on
the matter [p196] of A, is greater than that of A for itself. As to
the action of the canal on the portion _a_, _b_, that will be equal,
and exerted in contrary directions at its two extremities; it will
not, therefore, be either adverse or favourable to the movement of
the fluid in the canal: and the same will be the case with respect
to the pressures exerted at _a_ and _b_, by the external liquids, as
long as they are equal: nevertheless, the action of the canal, and
the external pressures, will prevent the thread of fluid from being
broken, so that it will move without interruption in the direction
in which it is drawn by the greatest attraction, or from _a_ to _b_.
Hence will result an elevation of the level of B, and, consequently,
an increase of pressure at the extremity _b_, of the passage, and
this elevation will proceed until the difference of pressure in _a_
and _b_ shall be equal to that of the attractions exerted by the two
fluids A and B, on the thread _a b_; this effect will be produced
the more rapidly as the division is pierced with a greater number of
passages similar to that which has been considered.
Now let us examine what would occur if the division were formed
of two others different in their nature, and exactly superposed;
exerting no action on one of the liquids, B for example, and one
only acting on the other liquid. The liquid B will then retain its
original position undisturbed; in consequence of the action it exerts
upon itself it cannot penetrate the canal _a b_, just as mercury
cannot escape by a capillary aperture made in a barometer-tube.
It will be the same with A, when that face of the division which
exerts no action upon the liquid is turned towards it; so that how
numerous soever the apertures, the two liquids would, under such
circumstances, remain separate and preserve their original level. But
if the division be turned so that the face which acts upon A shall
be in contact with that liquid, it will penetrate the canal _a b_
by means of capillary attraction; and the velocity which the liquid
urged by this force may acquire, may make it pass that point in the
canal where the division changes its nature, and even make it reach
the extremity in the liquid B, so that it is possible that the liquid
A should entirely fill the canal _a b_, as in the case which has
already been examined. Then if we always suppose the attraction of B
for A to be superior to that which A has for itself, the thread _a
b_ will flow into B until the level of the latter is so far altered
that the excess of pressure at _b_ can balance the difference of
attractions exerted by the two liquids at _a_ and _b_.
M. Poisson then observes that, without pretending to assign a cause,
exclusive of all others, for the phenomena of absorption by vegetable
and animal membranes observed by M. Dutrochet, his object is to
show that effects which have at least a great resemblance to these
important phenomena, may be produced by capillary action conjoined
with the difference of affinity existing between heterogeneous
substances without the assistance of electricity, either moving or
quiescent. It appears that M. Dutrochet afterwards [p197] found
mineral substances, as a piece of slate, might be substituted for the
organized tissues; this being the case, the opinion which refers such
effects to a general cause, as capillary attraction, acquires more
probability.
3. _Novel Use of the Plough_.—Mr. Bruckmann states that he has
long thought the plough might be used in levelling roads and
clearing the foundations for fortifications. In 1824 he had an
opportunity of applying it in the construction of a canal required
to furnish a motive force for the service of the rock-salt works of
Friedrichshall. The bed was to have a section of 700 square feet, and
it had been calculated that the excavations would require 200 men for
two years, whereas the king of Wurtemburg wished it to be done in one
year from the spring of 1824.
Three ploughs were employed; the first had two handles, a coulter,
and a share, the latter being in the form of a wedge. This plough
was preferred in the beds and gravelly grounds; and it was found
advantageous to give it an oscillatory movement by the handles during
its progress. Drawn by eight horses, it could turn up 25,000 cubic
feet of an argillaceous soil, in three hours; with ten horses it
turned up 19,800 cubic feet of a gravelly soil, in the same time.
This plough was tried in 1815, against fifteen others of the ordinary
kind, in the construction of a watercourse for a mill; all the
fifteen were quickly broken by the work.
The second plough had two handles and a coulter, but the share had
only one cutting edge, which was rounded and with an ear. It was
made five times as strong as an ordinary plough, and succeeded well
in compact and argillaceous soils, where, with eight horses and four
men, it moved 48,000 cubic feet of earth in three hours. In case of
fracture ten minutes sufficed to change the coulter and share, and,
during the work, 2,300,000 cubic feet of earth were loosened by it.
The third plough was smaller and lighter, it had two handles, a
coulter, an ear, and a share, the latter lance-shaped. It was used
for excavating the sides of the canal, on which the horses attached
to the first plough found it difficult to walk because of the
inclination. It was worked by ten or twelve men.
To establish an accurate comparison between the work of these ploughs
and that done by the pickaxe and spade, a piece of ground was wrought
solely in the latter manner by six strong working men. The result of
a long trial was the breaking of 150 cubic feet of ground by each man
in nine hours. Comparing this result with the work of the ploughs,
the following are the results:—The first plough did the work of 477
men, the second of 960 men, and the third that of 50 or 60 men. The
canal was finished on April 30th, 1825, the ploughs having saved
32,000 days, according to the work-day of a labourer.—_Bull. Univ._
D. vii. 343. [p198]
4. _Discovery of Rocks under the Surface of the Sea_.—The fishers
of the Mediterranean use an apparatus for the discovery of rocks
beneath the surface in those places where they wish to cast their
nets, which supplies, in a great measure, the insufficiencies of the
ordinary means of taking soundings. The method consists in carrying
a long and thin cord over the bottom to be examined, and which, when
it meets with an obstacle, is stopped by it and becomes folded in
the place where it occurs. It will easily be understood, that when a
cord has been carried over a certain space without meeting with any
resistance, that proof is obtained of the non-existence of rocks or
other obstacles, at a depth less than that to which the cord has been
sunk; and as the examination can easily be carried on to 100 feet
below the surface, it may be said that, wherever such an apparatus
has passed unimpeded, the navigation is free. If, on the contrary,
some isolated rocks are found during the examination, the place where
the cord becomes doubled points out the locality, which may then
be determined more accurately by other trials, and the summit and
neighbourhood of the submersed rocks be accurately examined by means
of soundings.—_Annales Marit._; _Bull. Univ._ F. viii. 44.
5. _Paper to resist Humidity_.—This process, which is due to M.
Engle, consists in plunging unsized paper once or twice into
clear solution of mastic in oil of turpentine, and drying it by a
gentle heat. The paper, without becoming transparent, has all the
properties of writing-paper, and may be used for the same purposes.
It is especially recommended for passports, workmen’s books, legal
papers, &c. When preserved for years it is free from injury, either
by humidity, mice, or insects. It is further added, that a solution
of caoutchouc will produce even a still better effect.—_Kunst und
Gewerbe-blatte_.
6. _Professor Amici’s Microscopes_.—This distinguished personage has
lately exhibited to the _savans_ of this country two microscopes of
his own workmanship,—an achromatic refractor, and a reflector of his
own particular invention. The object-glass of his refractor is of a
very complicated construction, and is composed of three double-object
glasses combined together in the space of about an inch. The
flint-glass from which his concaves are formed is of the manufacture
of Frauenhofer; his convexes are of Dutch plate, crown-glass, and
French plate, separately. Each object-glass detached has but a small
aperture, and is of long focus; but when the three are combined
together, the angle of aperture is very considerable, and the focus
short. By this ingenious arrangement the trouble and difficulty
of manipulating deep single-object-glasses of large aperture is
avoided; but advantages gained one way, in practical optics, are
generally lost in another, and the twelve surfaces of the objective
produce a kind of softness and muddiness in [p199] the image strongly
contrasted by the effect of a good single triple-glass of equivalent
power. When, however, only two of the object-glasses are combined,
the effect is very fine. Between the object-glass and eye-glasses is
placed one of those prisms originally invented by Sir I. Newton to
act as an eye-piece of his telescope, and of which a description may
be seen in his correspondence at the end of Dr. Gregory’s Optics. The
utility of the introduction of this device appears very questionable
in an instrument already so complicated. The diversion of the rays
into a course at a right angle to their original progress (merely to
give an horizontal instead of a vertical position to the body) is
surely no warrant for the employment of two extra refracting surfaces
and one reflexion, which cannot fail to have a pernicious influence
on the formation of the image. An horizontal position of the body
is attained with the utmost facility by a proper construction of
the mounting, &c. Setting aside the dulness of the image produced
by the numerous refractions, the performance of the instrument on
test-objects was highly respectable and satisfactory.
The reflector is a modification of the original construction
recommended by the Professor, who seems to have profited by the
schooling he received from Dr. Goring, and now sails much closer
to the wind than he did. His objective metal is now two inches
focus, with an aperture of 1-1/2 inch; but half an inch is cut
off for the purpose of preventing the bad effect of the marginal
rays, so that only 1 inch of the central portion of the metal is
employed;—the diameter of the diagonal mirror is also reduced to its
proper standard, by which means the blot in the centre of the visual
pencil is rendered as small as possible. It may be asserted of this
instrument, that it does as much as can possibly be expected from an
objective part of 2 inches focus, showing many test-objects faintly,
and with much effort; but it is totally unable to compete with deeper
ones equally perfect and of the same angular opening. The Professor
has, in some of his instruments, reduced the focus of the elliptic
metal to 1-1/2 inch, and will, no doubt, gradually slide into the
adoption of that radical reform in his instrument, so happily carried
into effect in this country by Dr. Goring, in conjunction with Mr.
Cuthbert,—at least if the figuration of elliptic metals of 3/10
inch focus with 2/10 inch of aperture shall not surpass his powers
of execution. During the Professor’s stay in this country there
was a grand field-day at his hotel, at which _both his microscopes
were tried against the Goringian modification of the reflector, the
superior weight of metal of which completely beat every thing opposed
to it_. For the honour of the Professor it must be stated, that he
admitted this defeat with great candour and good sense, and even had
some difficulty in believing in the identity of some of the objects
used, so differently was the ordinary apparent structure developed
by the English improvements on his instrument. It may with safety
be averred that no refractor, at least, will ever be [p200] made
to surpass _Dr. Goring’s improved Amician Engiscope_; and it seems
equally certain that no other reflector will ever be invented capable
of the same facilities of application to the examination of both
opaque and transparent objects. If Professor Amici has been beaten,
it has been done with his own weapons,—the copy has surpassed the
original,—the child, by virtue of foreign nursing and tuition, has
exceeded the stature and strength of the father.
II. CHEMICAL SCIENCE.
1. _On the Specific Heat of Gases, by_ MM. de la Rive _and_
Marcet.—The principle on which these philosophers proceeded in
their researches, was, to expose equal volumes of different gases
to an equal source of heat during equal times, and to judge, by the
augmentation of elastic force in each gas, the temperature which it
had acquired. The apparatus was a kind of manometer, and consisted
of a glass balloon to retain the gas, and a bent tube attached to
it, which, descending into a vessel of mercury, served to show, by
the column of metal within it, what was the elasticity of the gas.
This method was adopted, because, i. The gas was not altered in
volume by the change of temperature, its elasticity only changing:
ii. The temperature was indicated by the gas itself, and not by a
thermometer: iii. Water was easily separated previously from the
gases, and excluded from the apparatus: iv. All the gases were placed
in exactly the same circumstances, so as to render it unnecessary to
refer to any calculation for the purpose of comparison.
Two methods of applying heat were resorted to: in one the balloon,
containing the gas at a certain temperature, was placed in water at
a higher but constant degree, for a certain time (generally 4′),
and the elevation of temperature noticed: in the other, the balloon
with the gas was inclosed in a larger copper balloon, blackened
inside, and the space between the two exhausted as much as possible
of air; the apparatus being then immersed in warm water, the heat
gained access slowly to the gas, and the time of each experiment
was increased, at the same time that certain sources of error were
avoided.
The gases experimented with were, atmospheric air, oxygen, azote,
hydrogen, carbonic acid, olefiant gas, oxide of carbon, nitrous
oxide, nitrous gas, sulphuretted hydrogen, ammonia, sulphurous
acid, muriatic acid, and cyanogen. Great care was taken in their
preparation. The result of the experiment was very unexpected; for,
during the five minutes allotted for each, all had acquired the same
temperature,—a circumstance which proves that they all have the
_same specific heat_. The equal volumes of gas at the pressure of
65 centimeters (15.59 inches) and the temperature of 20°C., being
exposed to a source of heat at 30° C., acquired a mean temperature
of 6.32 degrees in five minutes, the extreme difference, in any of
the experiments, not being more than 0.04 of a [p201] degree. One gas
only forms an exception to the above statement, namely, hydrogen,
which was always heated more than the others, namely, to 6.6 degrees
in the five minutes. This effect is considered as due not to any
difference in specific heat, but to a difference in conducting power.
Experiments were then made with dilated gases, to ascertain whether
dilatation caused any change in capacity, and it was found to
diminish slowly but regularly with the diminution of pressure. These
results, with a third which is also interesting, have been thus
generally expressed by the authors at the end of their memoir.
i. All gases in equal volumes, and at the same pressure, have the
same specific heat.
ii. Other circumstances being the same, the specific heat of gases
diminishes with diminution of pressure, and equally for all the
gases: the progression converges slightly and in a ratio much less
than that of the pressures.
iii. Each gas has a different conducting power, _i.e._, all the gases
have not the some power of communicating or receiving heat.—_Ann. de
Chimie_, xxxv. 5.
2. _On the Incandescence and Light of Lime_.—The experiments made
by Lieutenant Drummond upon the light of lime and other earths when
highly ignited, with the highly interesting application which he has
made of that emitted from lime, to the purpose of geodesical surveys,
has induced M. Pleischel to repeat and vary the results. He states
that the utmost light is given by lime; the earth being pulverised
and exposed on burning charcoal to the heat excited by a jet of
oxygen falling upon it. He endeavours to account for the effect, by
supposing a kind of pulverulent atmosphere disengaged from the lime
at the high temperature used, and considers that the substances which
are competent to emit molecules only in the gaseous state, cannot
produce this intense light.—_Zeitschrift für Physik_, &c.
3. _Evolution of Heat during the Compression of Water_. May 14,
1827.—M. Arago announced to the Academy of Sciences, that M. Despretz
had ascertained experimentally, that the compression of water by
a force equal to 20 atmospheres, caused the disengagement of one
sixty-sixth part of a degree of heat.
4. _On Electrical Excitation_.—M. Walcker affirms positively from
experiments made with great care, that three bodies of different
exciting power are necessary, in every case of excitation of
electricity by contact, and that all the phenomena of this kind are
subject to this condition. If, for instance, two portions of the same
metal being put in contact, electricity is produced, it is because
there are three different states of temperature brought into play,
one being the result of the other two, and a mean between them. One
fact which more than any other sanctioned this idea, was, that the
electric [p202] currents were the more apparent as this third state
of temperature was made more sensible.—_Bull. Univ._, A. vii. 374.
5. _Magnetic Repulsion_.—A very remarkable result has been obtained
by M. Becquerel, from the use of an extremely delicate magnetic
arrangement, which he has for the present called a _sideroscope_. Its
use is exactly the same in principle as that of the magnetic needle,
indicating iron, for instance, by the attraction manifested; but
it is so delicate that it will show it in the most minute quantity
possible, as, for instance, in gold, silver, or copper money,
innumerable minerals, &c. This instrument shows no magnetic power or
attraction in gold, silver, copper, palladium, tin, lead, zinc, or
brass, when chemically pure, and a great many vegetable and mineral
substances have no action on it: but the most curious result is, that
very pure bismuth and even that of commerce has a _repulsive_ power,
which, if it be found ultimately to be independent of any magnetic
_polarity_, is the first fact of the kind that has been made known.
Antimony also presents the same phenomenon.
6. _Diminished Solubility of Substances by Heat_.—Mr. Graham
has added one to the few facts of this kind with which we were
acquainted, and has accompanied its description with some very
interesting considerations, which may be found at length in the
Philosophical Magazine, N. S., ii. 20. The salt experimented with by
Mr. Graham is the phosphate of magnesia; which may be prepared by
mixing a solution of 21 parts of phosphate of soda with one of 15.375
parts of sulphate of magnesia: within 24 hours the phosphate of
magnesia precipitates in acicular crystals; they should be agitated
with repeated portions of water, then thrown upon a filter with more
water, and left to dry.
Solutions were obtained by occasionally agitating this salt with
water in the proportion of 2 ounces to a pint of the fluid, for
four days; being then decanted and filtered, they had a sweetish
taste. A quantity of this fluid being heated in a water-bath, became
turbid before the temperature had attained 120° F.; at 212° a cloudy
precipitate slowly subsided, and the supernatant fluid became nearly
transparent. The precipitate was found to be anhydrous phosphate of
magnesia; and, by further experiment, the difference in solubility
was found to be such, that water at 45°, dissolving 1/744th part its
weight of the anhydrous salt, water at 212° only dissolved 1/1151th
part. When in the state of crystals, or as hydrate, the proportions
of salt were 1/322 and 1/498 to 1 of water.
Mere continuance of the heat had no effect in increasing the
precipitate either of this salt, or from aqueous solution of lime,
provided no part of the solution was at any time converted into
vapour; but if the solution only occupied a small part of the vessel,
and ebullition came on, then, although all the water might be
returned to the solution, yet the precipitation went on, and might
be [p203] increased _ad libitum_, particularly in the case of lime
water. The cause of the precipitate appears to be the same in all
these cases. The moment a drop of the solution is converted into
vapour, it deposits the quantity of lime or salt which it held in
solution; and in the case of bodies which dissolve so sparingly and
with so much difficulty, although the water be returned again to the
solution, it is incapable of re-dissolving what it has deposited. We
know that it would be a hopeless task to form a saturated solution of
lime by agitating with the water no more than the few grains which
it is capable of dissolving; and in the case of ebullition, when the
lime is once deposited, there should be the same difficulty in taking
it up.
Mr. Graham states that he has observed this effect not only in
lime-water and in solution of phosphate of magnesia, but to a certain
extent in all bodies of difficult solubility, in the sulphate of
lime, for instance, even when greatly diluted; and he believes that
the deposite from slight boiling observed in many mineral waters,
and generally attributed to the dissipation of carbonic acid gas,
depends, in some instances, upon this cause. However weak the
solution may be, it is evident that a portion of the salt may be
deposited in this way.
7. _On the Composition of Cyanic Acid_.—M. Wohler some time since
announced the production of cyanic acid, and cyanates, corresponding
in composition to the substance presumed to exist in the fulminating
compounds of silver, mercury, &c., the nature of which was made out
by MM. Liebig and Gay Lussac. M. Liebig, upon repeating M. Wohler’s
experiments upon his cyanate of silver, obtained only 71.012 per
cent. of oxide of silver, instead of 77.23, which was the quantity
present according to M. Wohler’s analysis, and concluded that the
acid was the cyanous, and not the cyanic. The latter philosopher was
consequently induced to repeat his experiments: one of his methods
of decomposing the cyanate of silver was by muriatic acid gas: at
first liquid cyanic acid forms, which is very soon transformed into
a white crystalline mass; but, on continuing the operation, and
applying a higher heat, a large quantity of muriate of ammonia and
cyanic acid is evolved. This process indicated 77.5 per cent. of
oxide of silver in the salt. Another process consisted in dissolving
the cyanate in nitric acid, and precipitating the silver by muriatic
acid, the result was 77.05 of oxide per cent. A third analysis, made
by reducing the silver of the salt, gave a result of 77.35 per cent.
oxide. The mean of these is 77.3, and the theoretical number obtained
by calculation is 77.23, so that the acid appears to be truly the
cyanic; and the curious fact of its being the same in composition
with that in the fulminating compounds of silver and mercury, but
very unlike in properties, still remains undisturbed.—_Bull. Univ._,
A. viii. 53.
8. _Iodous Acid_.—According to M. Wohler, the iodous acid of [p204]
M. Sementini[35] is nothing more than a mixture of chloride of iodine
and iodine. When saturated with carbonate of soda, the iodine in
solution is precipitated, and on evaporating the solution to dryness,
and heating it strongly, the residue fuses, and by proper tests is
found to be a mixture of chloride and iodide of sodium.
These statements apply only to the iodous acid: as to the oxide of
iodine, no source of chlorine exists in the process last described by
M. Sementini.
FOOTNOTE:
[35] See the last volume of this Journal, p. 477.
9. _On Manganesic Acid, by_ M. Unverdorben.—When manganesate
of potash is distilled with a little anhydrous sulphuric acid,
manganesic acid is evolved in the form of a red transparent gas,
which dissolves in water, forming a red solution. The gas frequently
decomposes spontaneously in the retort, with explosion, producing
oxide of manganese and oxygen.
Manganesate of potash was analysed by distilling it with excess of
sulphuric acid, collecting the oxygen disengaged, and estimating the
proportion of protoxide of manganese and salts of potash remaining in
the retort. According to these experiments the acid consists of
Manganese 58.74
Oxygen 41.26
------
100.00
And the manganesate of potash of Or being calcined
Potash 25.63 32.75
Manganese acid 52.44 67.25
Water 21.93 ------
------ 100.00
100.00
_Ann. des Mines_, 1827, p. 145.
10. _Heavy Muriatic Ether, and Hydrocarburet of Chlorine or Chloric
Ether_.—Some comparative experiments have been made on these two
substances by M. Vogel. He prepared the former of them by passing
chlorine gas into alcohol. The muriatic acid was then separated by
distilling the fluid from off chalk, in which operation the muriatic
ether and alcohol passed over together, and these were divided by the
addition of water, which dissolved the latter, and left the former.
The chloric ether was made as usual from chlorine and olefiant
gases. The results that were obtained by acting on these substances
by a high temperature, potash, phosphorus, &c., induced M. Vogel
to consider them as identical in composition, notwithstanding some
differences in their physical properties; the specific gravity of the
muriatic ether was 1.134, that of the chloric ether 1.214, and the
odour of the latter is more aromatic, and the taste more sweet than
of the former.
Whilst passing the chlorine into the alcohol, M. Vogel observed
[p205] that if the sun shone upon the substances when the action was
nearly complete, each bubble of chlorine as it entered the alcohol
produced a bright purple flame, a dense white vapour, and caused
violent concussions in the liquid; another curious instance, in
addition to the many that are known, of the power of solar light over
chemical action.—_Journ. de Pharm._ 1826, p. 627.
11. _Test for the Presence of Nitric Acid_.—The following method is
one devised by Dr. Liebig, for the detection of this substance, which
it will effect, he says, when there is not more than a four-hundredth
part of the acid present. The liquid to be examined must be mixed
with sufficient sulphuric solution of indigo to acquire a distinct
blue colour, a few drops of sulphuric acid added, and the whole
boiled. If the liquid contains a nitrate, it will be bleached, or,
if the quantity is very small, rendered yellow. By adding a little
muriate of soda to the liquid before applying heat, a five-hundredth
of nitric acid may easily be discovered.—_Ann. de Chimie_, xxxv. 80.
12. _Peculiar Formation of Nitre_.—The leaves and stems of beet root
contain oxalate and malate of potash. Some leaves were tied together
and hung up in a warm and slightly-humid place, where there was but
little light, to dry. Being examined at the end of several months,
they were found penetrated with, and covered by, an immense number
of minute crystals of nitre. The oxalic and malic acids had been
replaced by nitric acid; but whether from animalized matter naturally
in the leaves of the plant, or from the action of the air, or in what
manner, is not known.—M. HENRI BRACONNOT, _Ann. de Chimie_, xxxv. 260.
13. _Experiments on Fluoric Acid and Fluates, by_ M. Kuhlman.—These
experiments were made with dry sulphuric acid and fluor spar, with
the intention of proving that fluor spar is truly a compound of
fluorine and calcium, and not of fluoric acid and oxide of calcium.
A quantity of anhydrous sulphuric acid was prepared with great care,
and collected in a glass tube; the latter was then connected with
a platina tube charged with fluor spar, which had previously been
calcined in a platina crucible, and a glass tube was connected with
the other end of the platina tube for the purpose of conducting and
facilitating the collection of the gas evolved over mercury. The
fluor spar was heated to redness, and then the temperature of the
sulphuric acid raised so as to cause a stream of it in vapour to
pass over the fluor spar; but there was not the slightest reaction,
the sulphuric acid recondensed in part in the farthest tube, and no
trace of fluoric acid was produced. Dry sulphuric acid was then put,
in the liquid state, in contact with dry fluor spar, but there was
no decomposition, and no portion of the spar was converted [p206]
into sulphate of lime. The first experiment was then repeated, with
the difference of using hydrated sulphuric acid of specific gravity
1.842, and there was instantly much fluoric acid produced, which
acted upon the glass.
As Berzelius found 100 parts of fluor spar, when acted upon by
sulphuric acid, to yield 175 parts of sulphate of lime, equal to
73.553 parts of lime, or 52.819 of calcium, it follows that 100
parts of fluoride of calcium should contain 47.181 of fluorine and
52.819 of calcium. By the assistance of this result, and further
experiments, M. Kuhlman proceeded to ascertain the composition of
hydro-fluoric acid. Dry muriatic acid gas was passed over calcined
fluor spar heated to redness in a tube of platina; the fluoride of
calcium was decomposed, free hydro-fluoric acid was evolved, and
chloride of lime remained in the tube. The hydro-fluoric acid acted
upon the glass tubes, but being received in water was entirely
dissolved, with the exception of the silica it had separated from
the glass: no trace of hydrogen appeared. One hundred parts of
fluoride of calcium thus treated became 143.417 parts of chloride of
calcium, the 52.819 parts of calcium having united to 90.598 parts of
chlorine. But this latter quantity must have liberated 2.511 parts of
hydrogen, which must, therefore, have combined with the 47.181 parts
of fluorine in the spar, to form 49.692 parts of hydro-fluoric acid.
This latter body, therefore, consists of 94.941 fluorine, and 5.059
of hydrogen per cent. A small quantity of chlorine was set at liberty
during the experiment, the author thinks, from a little manganese in
the fluor spar.
M. Kuhlman found that all the chlorides, when subjected to the action
of anhydrous sulphuric acid in vapour, resisted decomposition, except
the chloride of sodium, which gave a small quantity of sulphate of
soda, and a double salt of soda and platina, crystallizing in fine
needles of a yellow colour. No doubt is entertained that, in the
latter case, the common salt and sulphuric acid were not perfectly
dry.—_Bull. Univ._
14. _Crystallization of Phosphorous_.—By the fusion and careful
refrigeration of a large quantity of phosphorus, M. Frantween has
obtained very fine crystals of an octoedral form, and as large in
size as a cherry-stone.
15. _Solutions of Phosphorus in Oils_.—The solutions of phosphorus
in fixed oils are so luminous as often to be resorted to for the
exhibition of this peculiar property of phosphorus; but M. Walcker
has remarked, that the power which they ordinarily possess is
instantaneously destroyed by the addition of small quantities only of
certain other substances, as the essential oils. The rectified oils
of turpentine and amber, the oils of rosemary, bergamotte, lemon,
camomile, angelica root, juniper berries, and parsley seed, [p207]
the oil obtained by the distillation of the nutmeg, all produce this
effect when their quantity is not more than one-fiftieth part of the
luminous oily solution of phosphorus. The same effect is produced by
adding about a fifth of the oils of anniseed, cajeput, lavender, rue,
sassafras, fern, cascarilla, mint, orange flowers, fennel, valerian,
cherry laurel, or bitter almonds, or balsam of copaiba; but the oil
of cinnamon, rectified petroleum, balsam of Peru, and camphor, have
no such effect.—_Annal. der Phys._ 1826, p. 125.
16. _On the Inflammation of Powder when struck by Brass, &c._—Iron
has been excluded from powder-works as subject to cause sparks by a
blow, and brass and copper have been recommended in its place. M. le
Col. Aubert has remarked, that brass on brass can inflame powder, and
has made experiments on the subject before a committee, the result of
which is as follows:—Inflammation of the powder takes place when the
blow is given by iron against iron; iron against brass; brass against
brass; iron against marble; lead against lead, or against wood,
when the blow is produced by a leaden ball shot from a fire-arm. As
yet the powder has not been inflamed by the blow of an iron hammer
against lead or wood.—_Bull. de la Soc. d’Encouragement;_ _Bull.
Univ._
17. _Cementation of Iron by Cast Iron_.—Pure iron, when surrounded
by, and in contact with, cast iron turnings, and heated, is
carbonised very rapidly, so as to harden, to temper, and, in fact,
to exhibit all the properties of steel. M. Gautier finds this a very
advantageous process in numerous cases, especially where the articles
to be case-hardened, or converted into steel, are small, as iron
wire, or wire gauze. The temperature required is not so high as that
necessary in the ordinary process of cementation, and the pieces to
be carbonised are not injured in form. The kind of cast iron used
should be the gray metal, and the more minutely it is divided the
more rapid and complete is the operation. By covering the mass of
cast metal, in which the iron to be carbonised is enveloped, with
sand, oxidation, from contact of the air, is prevented, and the cast
metal may be used many times. Plumbago experimented with in the same
manner does not produce the effect.—_Jour. de Pharmacie_, 1827, p. 18.
18. _On the Preparation of Ferro-prussiate of Potash, by_ M.
Gautier.—Numerous investigations induced M. Gautier to conclude,
that, i. When animal matter is calcined alone it yields but little
cyanogen. ii. That when mixed with potash it gives more, but the
cyanuret is not ferruretted. iii. That ammonia is then produced in
large quantity. iv. That the substitution of nitre for potash, and
the addition of iron or scales of iron, augmented the production of
cyanogen, and gave a ferro-prussiate. The following is the process
of manufacture to which M. Gautier has ultimately arrived, [p208]
and which he has practised for some years. The proportions of the
materials are—
Blood, considered as in the dry state, 3 parts
Nitre 1 part
Iron scales 1/50 of the blood employed.
The blood is first to be coagulated in a large copper cauldron, and
the serum being separated by means of a press, the coagulum is to be
returned to the cauldron with the nitre and iron. The quantity of
water contained in the blood is sufficient to liquify the salt, so as
to allow of an uniform mixture being effected. The mixture is then
removed, and exposed in an airy situation to dry, the putrefaction
of the blood being prevented by the nitre. When the desiccation is
complete, the mixture is charged into cast iron cylinders, which are
fixed in a reverberatory furnace, and in all things resemble those
used in the preparation of animal charcoal. These are to be raised to
a brown red heat, until no more vapour is disengaged, and then left
until nearly cold, after which the contents are to be withdrawn and
put into a wooden vat, with twelve or fifteen times their weight of
water, for an hour. The fluid is then to be filtered through a cloth,
and evaporated until of 32° of Beaué (specific gravity 1.284.) Being
then left to cool, a large quantity of well-crystallized bi-carbonate
of potash is obtained. M. Gautier says he has not, as yet, been
able to explain how it is that this bi-carbonate has been formed
at so high a temperature; a portion also appears to be decomposed
during the evaporation of the solution, which, at first but slightly
alkaline, becomes sensibly so by a prolonged evaporation.
As the same product is not obtained when potash is used in place of
nitre, it is probable that the elements of the nitric acid perform a
particular part in the operation.
The solution which has given the crystals of carbonate of potash
contains a little carbonate of potash, and much ferro-prussiate of
potash. It is to be concentrated to 34° (specific gravity 1.306), and
placed in wooden vessels lined with lead. In the course of some days
a greenish crystalline mass is obtained, which being redissolved in a
fresh quantity of pure water, and evaporated to 32° or 33° (specific
gravity 1.295), is to be recrystallized.
Sometimes, when using potash, M. Gautier has mixed nitre with it, and
has always obtained a richer product than when potash alone had been
employed.—_Jour. de Phar._ 1827, p. 11.
19. _Sulphocyanide of Potassium in Saliva_.—MM. Tiedemann and Gmelin
have observed the existence of this peculiar compound in saliva, in
two cases; the one when the fluid was secreted during smoking, and
the other when no such stimulus was applied.—_Ann. de Chimie_, xxxv.
266.
20. _Decomposition of Sulphate of Copper by Tartaric Acid_.—M. [p209]
Planche has observed, that when sulphate of copper is dissolved in
wine vinegar, for the purpose of preparing a corrosive liquid to be
applied to corns on the feet, that the tartaric acid present in the
vinegar displaces the sulphuric acid from a part of the salt, and an
insoluble acid tartrate of copper is produced.
21. _Separation of Arsenic from Nickel or Cobalt_.—The following
process by M. Woehler seems among the best of those intended for
freeing nickel or cobalt from arsenic in the dry way. It is founded
upon the circumstances that many alloys, when heated with sulphuret
of potash, become changed into a mixture of sulphurets, and that
sulphuret of arsenic is very soluble in sulphuret of potash. One
part of kupfernickle, fused and reduced to fine powder, is to be
mixed with 3 parts of carbonate of potash, and 3 parts of sulphur,
in a covered Hessian crucible. The heat is to be gradually raised to
redness, and until the mass is just entering into fusion, and by no
means so highly as to fuse the sulphuret of nickel which is formed.
When cold, water is to be added, which will dissolve the sulphuret
of potash, and leave a yellow crystalline powder, which is sulphuret
of nickel, retaining, perhaps, a little copper or cobalt, but no
arsenic, if the operation has been well performed. When, however, the
object is to have the nickel perfectly pure, it should be fused a
second time with sulphur and potash.
The method of freeing cobalt from arsenic, is the same as for
nickel; but it is then necessary to perform the operation a second
time. The cobalt (that of Tunaberg) has never been perfectly freed
from arsenic by one operation, but has never retained any after the
second.—_Archiv für Bergbau_, 1826, p. 186.
22. _Compounds of Gold_.—According to late experiments of Dr.
Thomson, peroxide of gold consists of
1 atom gold 25
3 " oxygen 3
---
28
and is consequently a teroxide. Muriate of gold consists of
2 atoms muriatic acid 9.25
1 " per oxide of gold 28.
5 " water 5.625
------
42.875
_Edin. Journal_, p. 182.
23. _Chemical Researches relative to certain Ancient Substances_.—M.
Vauquelin has analyzed, i. A poignard blade formed of copper only;
ii. A mirror, which was found to consist of 85 parts of copper, 14
of tin, and 1 of iron per cent.; iii. A blue colour found in a tomb:
[p210] it was composed of silica 70 parts; lime 9; oxide of copper
15; oxide of iron 1; soda mixed with potash 4. A blue identical with
this, both in colour and composition, was found in the bottom of a
furnace in which copper had been fused at Romilly.
M. D’Arcet has examined a bone from the fore part of an ox, which had
been placed as an offering to the divinity in an Egyptian tomb, and
found that it contained as much gelatine as recent bone, although
rather less is obtained by muriatic acid, (20 per cent. instead of
27) because of a deterioration of the bone. When burnt, it gave an
animal black as deep in colour as that from recent bone.
M. Le Baillif has examined some grains of corn, which were so well
preserved, that when put into boiling water iodine produced the
blue colour dependent upon starch. He also made some experiments on
a gummy substance, and on two cords from a musical instrument; the
latter were of animal substance.
M. Raspail examined some grain which was supposed to be wheat, but
found it to be torrified barley; it was covered with a substance
communicated probably by the oil and incense with which the grains
were bathed when consecrated. Similar grains were obtained by
roasting common barley.
The account of most of these researches is given in the Catalogue
raisonné et historique des Antiquités découvertes en Egypte, by M.
Passalacqua.—_Bull. Univ._ A. vii. 264.
24. _On the Bitter Substance produced by the action of Nitric Acid on
Indigo, Silk, and Aloes_, _by_ M. Just Liebeg.—The process by which
M. Liebeg obtains a pure and uniform substance from the action of
nitric acid on indigo, is as follows:—A portion of the best indigo
is to be broken into small fragments, and moderately heated with
eight or ten times its weight of nitric acid of moderate strength.
It will dissolve, evolving an abundance of nitrous vapours and
swelling up in the vessel. After the scum has fallen, the liquid is
to be boiled, and nitric acid added, whilst any disengagement of red
vapours is occasioned by it. When the liquid has become cold, a large
quantity of semi-transparent yellow crystals will be formed, and if
the operation has been well conducted, no artificial tannin or resin
will be obtained. The crystals are to be washed with cold water, and
then boiled in water sufficient to dissolve them. If any oily drops
of tannin form on the surface of the solution, they must be carefully
removed by touching them with filtering paper. Then filtering the
fluid, and allowing it to cool, yellow brilliant crystalline plates
will be obtained, which will not lose their lustre by washing.
To obtain the substance perfectly pure, the crystals must be
re-dissolved in boiling water, and neutralized by carbonate of
potash. Upon cooling, a salt of potash will crystallize, which should
be purified by repeated crystallizations.
On mixing the first mother liquor with water, a considerable brown
precipitate will be obtained, which being dissolved in boiling
[p211] water, and neutralized by carbonate of potash, will furnish
a large quantity of the potash salt. All the potash salt obtained
in these operations is to be re-dissolved in boiling water, and
nitric, muriatic, or sulphuric acid added; as the solution cools, the
peculiar substance will be observed to form very brilliant plates of
a clear yellow colour, generally in equilateral triangular forms.
Sometimes crystals are not formed after the action of the nitric acid
on the indigo, in which case the liquor must be evaporated, and water
added, when the substance will precipitate, and must be purified
as already described. Four parts of indigo yield one of the pure
substance.
When the substance is heated, it fuses, and is volatilized without
decomposition; when subjected to a sudden strong heat, it inflames
without explosion, its vapours burning with a yellow flame, and a
carbonaceous residue remaining. It is but little soluble in cold
water, but much more in boiling water; the solution has a bright
yellow colour, reddens litmus, has an extremely bitter taste, and
acts like a strong acid on metallic oxides, dissolving them, and
forming peculiar crystallizable salts.—Ether and alcohol dissolve the
substance readily.
When fused in chlorine or with iodine, it is not decomposed, nor does
solution of chlorine affect it. Cold sulphuric acid has no action
on it; when hot, it dissolves it, but water separates the substance
without alteration. Boiling muriatic acid does not affect it, and
nitro-muriatic acid only with great difficulty.
These results show that no nitric acid is present in the substance,
and other experiments prove that no oxide of nitrogen exists in it;
it contains no oxalic or other organic acid, for when its salt is
boiled with chloride of gold, the latter is not reduced.
When heated to redness with oxide of copper, it gave a mixture of
nitrogen and carbonic acid, in the exact proportion of 1 volume of
the former, to 5 of the latter. This was a constant result, and in no
case was any sulphuric or muriatic acid left in the copper. 0.0625
grammes of the substance thus decomposed, gave 45 cubic centimeters
of the mixed gases, estimated at 0° C. (32° F.) and the pressure of
28 inches of mercury, according to which the acid would be composed
of carbon 32.392; nitrogen 15.2144; oxygen 52.3936 per cent. From the
mean of several experiments, it appeared that the following might
represent the composition correctly.—
12-1/2 atoms of carbon 93.75 or 31.5128
2-1/2 " azote 43.75 " 14.7060
16 " oxygen 160.00 " 53.7812
------- --------
297.5 100.
100 parts of the acid neutralize a quantity of base equivalent to
3.26 of oxygen, which is to the oxygen of the acid, as 1:16; the
equivalent number of the acid derived from the analysis of the [p212]
barytic salt was 306.3; by adding only 1/4 per cent. to the quantity
of baryta obtained in the experiment, 297.5, or the number expressed
by the above formula, would be obtained.
When a salt of potash or baryta was decomposed by oxide of copper and
heat, the quantity of carbonic acid produced was a little short of
five times the quantity of nitrogen; but, upon adding that retained
by the alkali or earth, the proportion became exactly the same as in
the former cases.
_Welter’s bitter principle_ was prepared by acting on silk with ten
or twelve times its weight of nitric acid. The liquid, slightly
coloured at first, acquired a deep yellow upon adding water. It was
neutralized by carbonate of potash whilst hot, and left to cool, and
the salt of potash thus obtained, decomposed by muriatic, nitric, or
sulphuric acid. This acid, crystallized like that from indigo, formed
the same salts, and was composed in the same manner. Silk furnishes
much less of the substance than indigo. Dr. Liebeg has called this
substance _carbazotic acid_. The most important salts formed by it
have the following properties:—
_Carbazotate of Potash_—crystallizes in long yellow quadrilateral
needles, semi-transparent and very brilliant; it dissolves in
260 parts of water at 59° F., and in much less, boiling water: a
saturated boiling solution becomes a yellow mass of needles, from
which scarcely any fluid will run. Strong acids decompose it;
yet when an alcoholic solution of carbazotic acid is added to a
solution of nitre, crystallized carbazotate of potash, after some
time, precipitates.—Alcohol does not dissolve it. When a little
is gradually heated in a glass tube, it first fuses, and then
suddenly explodes, breaking the tube to atoms; traces of charcoal
are observed on the fragments. This salt precipitates a solution
of the protonitrate of mercury, but not salts, containing the
peroxide, or those of copper, lead, cobalt, iron, lime, baryta,
strontia, or magnesia. The slight solubility of this salt supplies
an easy method of testing and separating potash in a fluid. Even
the potash in tincture of litmus may be discovered by it; for, on
adding a few drops of carbazotic acid, dissolved in alcohol, to
infusion of litmus, crystals of the salt gradually separated. The
saturated solution of the salt at 50° F., is not troubled by muriate
of platina. The salt contains no water of crystallization. It was
analyzed by converting a portion of it into chloride of potassium by
muriatic acid: its composition is,—
Carbazotic acid 83.79
Potash 16.21
------
100.00
_Carbazotate of Soda_—crystallizes in fine silky yellow needles,
having the general properties of the salt of potash, but soluble in
from 20 to 24 parts of water, at 59° F.
_Carbazotate of Ammonia_ forms very long, flattened, brilliant,
[p213] yellow crystals, very soluble in water. Heated carefully in
a glass tube, it fuses, and is volatilized without decomposition;
heated suddenly, it inflames without explosion, and leaves much
carbonaceous residue.
_Carbazotate of Baryta_, obtained by heating carbonate of baryta, and
carbazotic acid with water. It crystallizes in quadrangular prisms of
a deep colour, and dissolves easily in water. When heated, it fuses,
and is decomposed with very powerful explosion, producing a vivid
yellow flame. The explosion is as powerful as that of fulminating
silver; a solution of chloride of potassium to which carbazotate of
baryta has been added, produces a precipitate of the potash salt,
and not more than 1-1/2 per cent. of potash remains in solution. 100
parts of the crystallized salt contain,—
Carbazotic acid 69.16 oxygen of the acid 16
Baryta 21.60 " earth 1
Water 9.24 " water 8
-------
100.00
_Carbazotate of Lime_, obtained like the salt of baryta, forms
flattened quadrangular prisms, very soluble in water, and detonating
like the salt of potash.
_Carbazotate of Magnesia_ forms very long indistinct needles, of a
clear yellow colour; is very soluble, and detonates violently.
_Carbazotate of Copper_, prepared by decomposing sulphate of
copper by carbazotate of baryta: it crystallizes with difficulty,
the crystals being of a fine green colour; it is deliquescent;
when heated, it is decomposed without explosion, and even without
inflammation.
_Carbazotate of Silver_.—Carbazotic acid readily dissolves oxide of
silver, when heated with it and water; and the solution, gradually
evaporated, yields starry groups of fine acicular crystals of the
colour and lustre of gold; the salt dissolves readily in water; when
heated to a certain degree, it does not detonate, but fuses like
gunpowder.
_Proto-Carbazotate of Mercury_, obtained in small yellow triangular
crystals, by mixing boiling solutions of the carbazotate of potash or
soda, and proto-nitrate of mercury. It requires more than 1200 parts
of water for its solution: for its perfect purification, it should
be heated with a solution of chloride of potassium, the insoluble
portion separated whilst the liquid is lost, and the peculiar salt
allowed to deposit as the temperature falls. When heated, it behaves
like the salt of silver.
All these salts detonate much more powerfully when heated in close
vessels, than when heated in the air; and it was a curious thing to
observe, that those with bases yielding oxygen most readily, were
those which exploded with least force. By heating some of the salts
previously mixed with chloride of potassium, &c., to retard the
action, it appeared that no carbonic oxide, but only carbonic [p214]
acid and azote were evolved during their decomposition by heat.
_On the Bitter Principle from Aloes_.—Upon distilling 8 parts
of nitric acid from 1 part of the extract of aloes, and adding
water to the remaining fluid, a resinous reddish yellow substance
precipitated, which, by washing, became pulverulent—it was
discovered by M. Braconnot. Upon evaporating the liquid separated
from the precipitate, it gave large yellow rhomboidal crystals,
not transparent, and but slightly soluble. These crystals, at
first mistaken for a particular substance, were soon found to be
a combination of oxalic acid with the bitter of aloes. The bitter
substances of aloes dissolved in 800 parts of water, at 59° F., but
in a smaller quantity of boiling water. This solution has a superb
purple colour. Silk boiled in it acquired a very fine purple colour,
on which neither soap nor acids effected any change, except nitric
acid; this changed the colour to yellow, but it was restored simply
by washing in water. All shades may be given to this colour by proper
mordants. Wool is dyed black in a peculiarly beautiful manner, by
the same process, and light has no influence on the colour. Leather
acquires a purple colour; cotton, a rose colour; but the latter will
not resist soap. Dr. Liebeg thinks that this is the only substance
from which a permanent rose dye for silk may be expected.—_Ann. de
Chimie_, xxxv. 72.
25. _On the Existence of Crystals of Oxalate of Lime in Plants_.—M.
Raspail has read a memoir to the Academy of Sciences, to prove the
analogy which exists in arrangement between the crystals of silica,
which are found in sponges, and those of oxalate of lime occurring in
the tissue of phanerogamous plants.
The latter crystals were observed, for the first time, by Rafn and
Jurine, who regarded them as organs of which they knew not the
use. They were then observed by M. de Candolle, who called them
_raphides_, and gave a figure of them, which, however, is inaccurate.
These crystals are really very regular tetraedrons. In many plants,
as _orchis_, _pandanus_, _ornithogalum_, _jacinthus_, _phytolaca_
_decandria_, _mesembryanthemum deltoides_, &c. they are very small,
not being more than 1/200 of a millimetre (.0002 of an inch) in
width, and 1/10 (.004 of an inch) in length. But, in the tubercles
of the Florence iris, they are as much as 1/50 (.0008 of an inch)
in width, and 1/3 (.01312 of an inch) in length, so as to be easily
capable of examination.—_Bull. Univ._ B. xi. 376.
26. _Fallacy of Infusion of Litmus as a Test_, _by_ M. Magnus.—When
pure water is heated for a sufficient time with infusion of litmus,
reddened by an acid, it restores the blue colour. It is supposed
that the heat gradually causes the free sulphuric acid, which had
occasioned the reddening, to combine with the excess of alkali
contained in the infusion, and thus to cause the restoration of the
blue colour. Hence this preparation cannot be used to test the [p215]
presence of ammonia in a solution, as water alone produces the effect
anticipated from the alkali. The earthy salts contained in ordinary
water also produce this effect.—_Jour. de Pharmacie_.
27. _Tests for the Natural Colouring Matter of Wine_.—M. A. Chevalier
states,—i. That potash may be employed as a re-agent, to ascertain
the natural colour of wines, which it changes from red to a bottle
green, or brownish green—ii. That the change of colour produced by
this substance upon wine is different for wine of different ages—iii.
That no precipitation of the colouring matter takes place, the latter
remaining dissolved by the potash—iv. That the acetate of lead should
not be employed as a test of the colour of wines, because it is
capable of producing various colours with wines of a natural colour
only—v. That the same is the case with lime-water, with muriate of
tin mixed with ammonia, and with subacetate of lead—vi. That ammonia
may be employed for this purpose, the changes of colour which it
produces not perceptibly varying—vii. That the same is the case with
a solution of alum to which a certain quantity of potash has been
added, and which may, therefore, be used for the purpose.—_Annales de
l’Industrie_.
28. _Test of the Presence of Opium_.—Dr. Hare says he can detect
opium in solution, when the quantity is not more than that given, by
adding ten drops of laudanum to half a gallon of water. The following
is the process:—a few drops of solution of acetate of lead is to
be added to the solution containing the drug; after some time an
observable quantity of meconiate of lead will fall down: from six to
twelve hours may sometimes be required, and the precipitation is best
effected in a conical glass vessel, for then, by gentle stirring now
and then to liberate that which adheres to the side, the insoluble
salt may be collected together at the bottom. About thirty drops of
sulphuric acid are then to be poured on to the meconiate by means
of a glass tube, after which as much of a solution of red sulphate
of iron is to be added in the same manner. The sulphuric acid will
liberate the meconic acid, and thus enable it to produce with the
iron the appropriate colour, which demonstrates the presence of that
acid, and consequently of opium.—_Silliman’s Journal_, xii. 290.
29. _Denarcotized Laudanum_.—Thinking it important to ascertain
whether, by the removal of narcotine from opium, the unpleasant
effects which, according to the opinions at present entertained
upon that subject, are produced by that drug would be removed, Dr.
Hare prepared some opium with ether, guided by Robiquet’s statement
that narcotine was soluble in that fluid: the opium was shaved by
rubbing it on the face of a jack-plane, and subjected four times
successively to as much ether of the specific gravity 0.735 as would
cover it, the operation being performed in a small Papin’s digester,
at a temperature near the boiling point of ether, and each [p216]
portion of the fluid being allowed twenty-four hours for its action.
A crystalline deposition was soon observed in the ether which had
been removed from the opium, and, allowing the stopper of the vessel
to remain out, nearly the whole of the liquid evaporated in a few
days, and left much coloured crystalline matter. This, Dr. Hare has
no doubt, was narcotine in an impure state. The opium was afterwards
subjected to as much alcohol as would have been required to convert
it into laudanum, had it been in the ordinary state; and this being
administered medicinally, was found to occasion none of those uneasy
and unpleasant sensations which often follow the use of ordinary
opium.—_Silliman’s Journal_, xii. 291.
30. _Extraction of Morphia from Dry Poppy Heads_, by M. Tilloy.—Make
an aqueous extract of the heads, add alcohol to the extract,
separate the alcoholic solution, and distil it; by this means the
gummy matter is separated. An extract like syrup will be obtained
by the distillation, which, being heated to make it thinner, and of
the consistency of treacle, is to be again treated with alcohol;
a separation of more gum, with much nitrate of potash, will be
effected. The solution being withdrawn, is to be distilled, and
the extract which will remain is to be acted upon by a sufficient
quantity of water, and filtered, to separate the resinous matter
present. The morphia may then be separated from this liquid,
either by ammonia, carbonate of soda, or magnesia. Ammonia does
not precipitate all the morphia; carbonate of soda precipitates a
large quantity, but, it separates resinous matter also, which is
found mingled with the morphia. Magnesia is preferable; but as the
liquid contains much free acetic acid, it is expensive to employ
the necessary quantity of pure magnesia: the liquid may, therefore,
be partly saturated, whilst hot, by carbonate of magnesia, or even
by carbonate of lime. A judgment, when no more must be added, must
be formed from the effervescence; then pure magnesia is to be
added, which will cause the liberation of ammonia; the whole is to
be left for twenty-four hours to cool: being then filtered, the
precipitate is to be washed, and, when dry, acted upon by alcohol.
Operating in this manner, morphia may be obtained from all kinds of
poppies.—_Bull. Univ._ E. viii. 10.
31. _Preparation of Morphia_.—Some curious experiments have been
described to the Académie de Médecine, by M. Robinet, relative to
the preparation of morphia. Having operated on the residue of opium
by muriatic acid, and precipitated the morphia from the muriatic
solution by lime, he wished to ascertain whether the mother liquor
contained any morphia that had escaped precipitation. He, therefore,
passed a current of carbonic acid gas through the solution, to
precipitate the lime in excess: this precipitate being washed,
dried, and acted upon by alcohol, was found mixed with a very large
proportion of morphia, which could [p217] be thus separated. The
washings of the precipitate being examined, were found free from
morphia.
M. Henry observed, at the same time, that, from experiments made
at La Pharmacie Centrale, it appeared that much more morphia
was obtained in those processes in which lime had been used to
precipitate the morphia, than in those in which magnesia had been
used.—_Bull. Univ._ C. xi. 225.
32. _Easy Method of obtaining Meconic Acid_, by Dr. Hare.—If to
an aqueous infusion of opium we add subacetate of lead, a copious
precipitation of meconiate of lead ensues: this being collected by
a filter, and exposed to sulphuretted hydrogen, meconic acid is
liberated: the solution is of a reddish amber colour, and furnishes,
by evaporation, crystals of the same hue. A very small quantity
produces a very striking effect in reddening solution of peroxide of
iron. Instead of sulphuretted hydrogen, sulphuric acid may be used
to liberate the meconic acid: the presence of the former in excess
does not seem to interfere with the power of reddening ferruginous
solutions, but any excess of sulphuric acid may be removed by
whitening, which is not acted upon sensibly by meconic acid; Yet, the
acid procured in this way did not crystallize so handsomely, or with
so much facility, as that obtained by sulphuretted hydrogen.
33. _On a New Vegetable Acid_.—This acid is crystallizable, but the
forms have not as yet been determined: it is less soluble in cold
water than tartaric acid; its aqueous solution precipitates lime
water in white floculi, just like tartaric acid, but the precipitate,
if dissolved in muriatic acid, re-appears on adding ammonia, whilst
that produced by tartaric acid does not produce this effect. The
new acid has a greater affinity for lime than muriatic or nitric
acids, for it precipitates the muriate and nitrate of this earth in
the manner of oxalic acid, but it differs from the latter in not
precipitating a solution of sulphate of lime. With potash it forms an
acid salt, slightly soluble in cold water: it precipitates acetate
of lead, and the precipitate holds much water in combination: the
tartrate of lead, on the contrary, is anhydrous. Notwithstanding
these circumstances, the equivalent number of this acid is within
a few thousandths of that of tartaric acid: when distilled, it is
decomposed, and produces an acid yellow liquid like tartaric acid,
leaving a light charcoal burning without residuum. M. Gay Lussac is
engaged in developing the chemical history of this substance.—_Bull.
Univ._ A. vii. 327.
34. _Altheine, a new Vegetable Principle_.—M. Bacon gives the
following directions for the preparation of this substance, which
he has discovered in the _Althea officinalis_. An extract of the
roots of the plant is to be made by means of cold water, and, when
concentrated, [p218] acted upon by boiling alcohol: the latter
will dissolve the acid malate of altheine, oil, &c.: the different
alcoholic decoctions are to be put together and will throw down a
crystalline deposite as they cool; the latter is to be separated
and dissolved in water, and the solution, when filtered, is to be
evaporated by a moderate heat, until like a syrup, and then set aside
to crystallize. The crystals procured are to be washed with a small
quantity of pure water, to separate the yellow matter from them, and
then dried upon paper. These crystals appear, to the naked eye, like
grains, needles, and feathers, but under the microscope present a
hexaedral form. They are of a fine emerald green colour, transparent,
brilliant, inodorous; unaltered in the air; they redden litmus
paper, are soluble in water, and insoluble in alcohol. The aqueous
solution of these crystals, acted upon by cold magnesia and filtered,
then restores the colour of reddened litmus paper; renders syrup of
violets green; and when evaporated furnishes the altheine free from
malic acid. When thus pure, the substance crystallizes in regular
hexaedral forms or in rhomboidal octoedrons; it affects litmus and
violets as just described: it is transparent, of an emerald green
colour, brilliant, inodorous, slightly sapid, unaltered by air, very
soluble in water, not soluble in alcohol, soluble in acetic acid,
with which it forms a crystalline salt.—_Ann. de Chimie_, xxxiv. 201.
35. _Rheine, a new Substance from Rhubarb_.—By acting upon one part
of Chinese rhubarb with 8 parts of nitric acid, s. g. 1.32, at a
moderate temperature, reducing the whole to the consistence of syrup,
and then diffusing it through water, M. Vaudin obtained a precipitate
which possessed peculiar characters, and to which he gave the name
of _Rheine_. When dry, it is of an orange yellow colour, without any
particular odour, and slightly bitter. It dissolves in water as well
as in alcohol and ether: the solutions become yellow by acids, and
rose red by alkalis. It burns nearly in the manner of amadou. Rhubarb
acted upon by ether only gave a similar substance, a circumstance
which proves that Rheine exists ready formed in rhubarb, and that it
is not acted upon by nitric acid.—_Ann. de Chimie_, xxxiv. 192.
36. _On Dragon’s Blood, and a new Substance which it contains_,
_by_ M. Melandri.—Pure dragon’s blood is, according to M. Melandri,
a scarce substance; the drops in which it occurs are rarely
transparent, generally opaque, and with a rough fracture: its colour
is blood red. Besides being soluble in alcohol it is entirely soluble
in oil and also in hot water, though a large quantity of the latter
fluid is required for the purpose. The aqueous solution is bitter,
astringent, and of a fine purple colour; by cooling, it becomes milky
and red. Gelatine does not alter its appearance; a proof that the
substance contains no tannin. Sulphate of iron forms a pale reddish
precipitate, so that no evidence of gallic acid is afforded. [p219]
Supposing that this substance might contain a principle analogous to
that latterly observed by M. Pelletier in logwood, &c. a portion of
it was dissolved in strong alcohol, the solution evaporated until
very concentrated, and then poured into cold water, an agglomerated
spongy substance was precipitated, which, after being washed with
cold water and filtered, was triturated with water containing
1/100th of sulphuric acid, and exhibited traces of chemical action
at a temperature of 22° (61°.6 F.) It then deposited a substance
upon the sides of the vessel, and the liquid became yellow and very
acid. The sediment, being carefully washed with water, was of a fine
red colour, varying according to the state of aggregation; it had
no taste or smell; was flexible between the fingers, and was quite
fluid at 55° (131° F.). This substance, which the author has called
_Dracine_, has some analogy with the vegeto-alkalis, although its
affinity for acids is but slight. The sulphate may be obtained, he
says, by adding sulphuric acid diluted with alcohol to an alcoholic
solution of _dracine_, precipitating the mixture by cold water, and
then applying a little heat; the sulphate of dracine collects at the
bottom, is to be washed with cold water until the latter no longer
reddens litmus paper, and then dissolved in hot water. This solution
becomes red by the smallest quantity of alkalis, and may be used as
a very sensible test of their presence. Dracine is also a good test
for acids, assuming a yellow colour with them. The small quantity of
carbonate of lime in filtering paper may be detected by sulphate of
dracine, the yellow solution instantly becoming red from its action,
and thus showing its presence.—_Bull. Univ._ C. xi. p. 157.
37. _Purification of Madder, by the Separation of its Yellow
Colouring Matter_.—The experiments of MM. Kuhlman, Colin, and
Robiquet[36], have induced M. G. H. de Kurrer to publish the means
which he has resorted to for the purification of madder, by the
separation of the yellow colouring matter from it; and thus rendering
it more fit to supply the various red, lilac, violet, and brown
colours which are required upon wool, silk, cotton and linen. Three
tubs or vessels are placed by the side of each other: in summer they
may be in the open air under shelter, but in the winter should be
placed in an airy cellar where the temperature may be retained at 18°
or 20° R. (73° to 77° F.). The first is that in which the soaking and
fermentation is to be effected: it should be 2 feet 8 inches deep,
and 2 feet 6 inches in diameter, for from fifty to fifty-five pounds
of madder. The second, or washing vessel, should be 5-1/2 feet deep,
and 3 feet in diameter; it should have three wooden cocks fixed into
it, the first 2 feet, the second 3 feet, and the third 4 feet from
the bottom. The third tub is for deposition; its height should be
4-1/2 feet, and it should have a cock at 1-1/2 foot from the bottom.
[p220]
On commencing the operation, 50 or 55 lb. of pulverised madder are
to be put into the first vessel, water is to be added, and stirred
into the mass until it stands 1-1/2 inch above the madder. The whole
is then to be left until fermentation comes on and has formed a coat
of madder at the surface; this usually takes place in 36 hours,
and at latest in 48 hours, according to the temperature. The mass
should now be transferred into the second vessel, which is then to
be filled with water, and being left for two hours, the madder will
fall to the bottom. The upper cock is then to be opened, after that
the second, and then the third; and the water which runs from the
two latter is to be put into the third vessel, that the rest of the
madder may separate from it. The madder in the second vessel is then
to be washed a second, third, or fourth time until the washing water
is colourless. Thus purified, the madder may be used in the processes
of dyeing, according to the known methods; but it is important in
summer that it should be used immediately, that a new (the vinous)
fermentation may be avoided. The madder deposited in the third
vessel, when washed and deposited, may be used like the rest. The
liquid first separated after the fermentation may be used in the
preparation of hot indigo baths, &c. instead of madder.—_Bull. Univ._
P. vii. 352.
FOOTNOTE:
[36] See page 239 of the last volume.
38. _On Indigo and Indigogene, by M. Liebeg_.—1-1/2 part of pure
indigo, 2 parts of proto-sulphate of iron, 2-1/2 parts of hydrate
of lime, and from 50 to 60 parts of water, were digested together
for 24 hours in a close vessel, which had previously been filled
with hydrogen. The clear liquor over the sulphate of lime and
oxide of iron, had a yellowish red colour, and was separated by
a syphon filled with hydrogen, and mixed with diluted muriatic
acid, containing some sulphite of ammonia dissolved; a dense white
precipitate was formed, becoming blue in the air. This was gathered
in a filter without contact of air, and washed with boiled water
containing sulphite of ammonia in solution, and dried at 212°, in
close vessels, through which a current of hydrogen was continually
passed. The upper surface of the mass became of a blue colour, but
the lower remained of a dull white.
This white substance was called Indigogene. It did not change colour
in dry air, but under water became of a deep blue, which by drying,
assumed a coppery appearance. The blue substance volatilized by heat
without leaving any residue, forming purple vapours, which condensed,
when cold, into crystals differing in nothing from sublimed indigo.
_Indigogene_ dissolves in alkalis without neutralizing them: it is
also soluble in alcohol, but insoluble in water or acids.
A given quantity of this indigogene was acted upon by ammonia, and
the weight of the undissolved blue portion ascertained, it appeared
that the weight of the pure portion dissolved was 0.404 grammes
(6.224 grains.) The solution was put into an inverted [p221] jar,
over mercury, and oxygen gas gradually passed in until absorption
ceased, and then the liquid containing the precipitated indigo was
evaporated to dryness at 212°. The weight of the substance was
increased to 0.047, _i. e._ 11.5 per cent.
Not having obtained indigogene _perfectly_ pure, M. Liebeg did not
attempt to analyze it for the ultimate composition. He remarks,
that indigo is, perhaps, the only organic body from which one of
its constituent parts may be taken without total decomposition; and
which, by oxidation, passes to the state of an indifferent body,
having much analogy with peroxides.—_Ann. de Chimie_, xxxv. 269.
39. _On the mutual Action of Ethers, and other Substances_.—From
experiments made by M. Henry, he concludes that when metals easily
oxidizable, or oxides which unite with acetic acid, are put into
sulphuric ether, they produce larger or smaller quantities of
acetates, probably, not by decomposing the sulphuric ether, but
the acetic ether which is always mixed with it; and that it is in
consequence of the saturation of the acetic acid set free from the
ether by this decomposition, that sulphuric ether does not redden
litmus paper when evaporated, whereas it acts differently when being
slightly heated, the quantity of acetic ether contained in it is
allowed to decompose by the action of the air.
Nitric and acetic ethers are described as being easily decomposed by
the action of many bodies without the assistance of heat, if aided by
time. Amongst the products of the action are the acids of the ethers,
acetates, and alcohol which dissolves the salts formed.—_Jour. de
Chimie Méd_.
40. _Faraday’s Chemical Manipulation_.—The kindness of a friend at
Bristol has pointed out to me an error in the directions relative to
alkalimetry, which I have given in the above work: this I am desirous
of correcting, and, by permission of Mr. Brande, have the opportunity
of doing so in the _Quarterly Journal of Science_.
The mistake, which arose from using the wrong specific gravity of two
that were required in calculation, occurs in the paragraphs (599,
600,) but fortunately is prevented from occasioning any experimental
error by the directions given in (602). The acid of specific gravity,
1.141, directed to be used, is too strong for the quantities marked
upon the tube. The substitution of one of specific gravity 1.127,
will correct the error, and may be obtained very nearly by mixing 19
parts, by weight, of strong oil of vitriol, with 81 parts of water.
The alterations required may be made in the volume with a pen, as
for errors of the press, by reading “1.127” for “1.141” in lines 25
and 30 of page 276, and lines 2 and 13 of page 277; and “nineteen”
for “one” in line 27, and “eighty-one” for “four” in line 28 of page
276.—M. F. [p222]
III. NATURAL HISTORY.
1. _On the Supposed Influence of the Moon_, by M. Arago.—There
is an impression very general with gardeners, that the moon has
a particular effect on plants, especially in certain months. The
gardeners near Paris gave the name of the _lune rousse_ to the moon,
which, beginning in April, becomes full either at the end of the
month, or more generally in May. According to them the light of the
moon, in the months of April and May, injures the shoots of plants,
and that, when the sky is clear, the leaves and buds exposed to this
light become red or brown, and are killed, though the thermometer
in the atmosphere is several degrees above the freezing point: they
confirm this observation, by remarking that, when the rays of the
moon are stopped in consequence of the existence of clouds in the
air, that then the plants are not injured, although the temperature
and other circumstances are the same.
M. Arago explains this observation of practical men, by a reference
to the facts and principles established by Dr. Wells. He has shown
that, in a clear night, exposed bodies may frequently have their
temperatures reduced below that of the surrounding atmosphere,
solely by the effect of radiation, the difference being as much as
6, 7, 10, or more degrees, but that it does not take place when the
heavens are obscured. M. Arago then observes, that the temperature
is often not more than 4, 5, or 6 degrees above the freezing point
during the nights of April and May, and that when the night is clear,
consequently when the moon is bright, the temperature of the leaves
and buds may often be brought by radiation below the freezing point,
whilst the air remains above it, and consequently an effect be
produced, which, though not dependent upon, accompanies the brilliant
unobscured state of the moon—the absence of these injurious effects,
when the moon is obscured, being also as perfectly accounted for
by these principles, from the knowledge that the same clouds which
obscure the moon will prevent the radiation of heat from the plants.
Hence, as M. Arago observes, the observation of the gardener is
correct as far as it goes, though the interpretation of the effect
which he generally gives is incorrect.—_Annuaire du Bureau des Long._
1827, p. 162.
2. _Luminous Appearances in the Atmosphere_.—An account is given at
page 242 of our last volume, from Silliman’s Journal, of certain
spots in the air near the horizon, which have been seen highly
luminous in Ohio, United States, by Mr. Atwater, and which often
induce the supposition that fires exist in their direction. Mr.
Webster says—“I have observed similar phenomena in New England: I
recollect one instance, when I resided at Amherst, in Hampshire
County, Mass., a bright light in the north-east, near [p223] the
horizon, appeared as the light of a building on fire appears at
night, at the distance of several miles. I expected, in that
instance, every hour to hear that some building in Shutesbury, or
New Salem, had been burnt, and, so strong was my belief of it, that
I repeatedly asked my neighbours whether they had heard of any such
event. At last, I met a gentleman who had just come from one of those
towns, who told me he had heard of no fire from that quarter, which
convinced me the phenomenon was merely atmospheric.”—_Silliman’s
Journal_, xii. 380.
3. _On the Determination of the Mean Temperature of the Air_.—This
subject has been investigated by M. G. G. Hallstrœm, who gives the
following algebraic formula, which correctly represents the mean
temperature for all Europe.
_v_ = 1/2 (_x_ _f_ + _x__e_)−0.33 + 0.41 sin. [(_n_−1) 30° + 124° 8′]
_v_ = mean temperature.
_n_ = the ordinal number of the month for which the temperature is to
be calculated (thus, for March, _n_ = 3).
1/2 (_x_ _f_ + _x_ _e_) = the mean temperature taken as the mean of
observations taken at ten o’clock in the morning and evening.
In winter 1/2 (_x_ _f_ + _x_ _e_) = _v_ very nearly; whilst, in
summer, this quantity is 3/4 of a degree greater than _v_ at Paris,
Halle, and Abo.—_Annal. der Phys. und Chem._ 1825, p. 373.
4. _Indelible Writing_.—As the art of man can unmake whatever the
art of man can make, we have no right to expect an _indelible ink_:
however, a sort of approximation to it may be made as follows:—Let
a saturated solution of indigo and madder in boiling water be made,
in such proportions as give a purple tint; add to it from one sixth
to one eighth of its weight of sulphuric acid, according to the
thickness and strength of the paper to be used: this makes an ink
which flows pretty freely from the pen, and when writing, which has
been executed with it, is exposed to a considerable, but gradual,
heat from the fire, it becomes completely black, the letters being
burnt in and charred by the action of the sulphuric acid. _If the
acid has not been used in sufficient quantity to destroy the texture
of the paper, and reduce it to the state of tinder, the colour may be
discharged by the oxymuriatic and oxalic acids, and their compounds,
though not without great difficulty_. When the full proportion of
acid has been employed, a little crumpling and rubbing of the paper
reduces the carbonaceous matter of the letters to powder; but by
putting a black ground behind them, they may be preserved, and thus a
species of _indelible writing_ is procured, (for the letters are, in
a manner, stamped out of the paper,) which might be useful for some
purposes, perhaps for the signature of bank-notes.
5. _Peculiar Crystals of Quartz_.—Mr. W. Phillips has met with some
remarkable crystals of quartz, which occurred imbedded in the [p224]
limestone of the Black-rock, near Cork. They are from the fourth
to the half of an inch in length, and about half their length in
width: they are smooth, externally, for the most part, and sometimes
considerably bright; they are of the colour termed smoky, or brown
quartz, externally, and may easily be separated from the limestone,
leaving a cavity of their exact form. On trying to cleave them, they
yielded parallel to one or other of the planes of the pyramid, like
common quartz, but at such fractures appeared to consist of alternate
and concentric prisms of smoky transparent quartz, and of gray
opaque, and somewhat granular limestone. On applying muriatic acid to
the surface, effervescence occurred along the gray parts, proving the
presence of limestone, but soon ceased: after an action continued for
some weeks, the gray parts became cellular, and so soft, as to admit
of being scraped by a knife. Mr. Phillips says, it seems reasonable
to conclude that such part of the gray substance as does not yield to
the action of the acid is siliceous or quartzose; and that the prime
difference between it and the smoky quartz surrounding it consists in
the different circumstances of crystalline aggregation under which
they are deposited. The crystals, with the somewhat analogous case of
the Fontainebleau sandstone, may serve to assist in the illustration
of some points relative to the laws of affinity, as operating in the
formation of crystals.—_Phil. Mag._ N. S., ii. 123.
6. _Native Iron not Meteoric_.—The following notice is by Mr. C. A.
Lee. Native iron, on Canaan mountain, a mile and a half from the
South Meetinghouse (Conn. U. S.). This is particularly interesting,
as it is the first instance in which native iron, not meteoric,
has been found in America. It was discovered by Major Barrall, of
Canaan, while employed in surveying, many years ago. It formed a thin
stratum, or plate, in a mass of mica slate, which seemed to have been
broken from an adjoining ledge. It presents the usual characters of
native iron, and is easily malleable. For some distance around the
place where it was found the needle will not traverse, and a great
proportion of the tallest trees have been struck with lightning.
Whether these phenomena are connected with the existence of a large
mass of native iron, I leave for others to determine: the facts,
however, may be relied on.
The specimen has been examined chemically, by Mr. Shepherd, at
Yale College. It is invested with highly crystalline plumbago, and
splits by the intervention of plates of plumbago into pyramidal and
tetrahedral masses. It is not equal to meteoric iron in malleability,
toughness, and flexibility, and has not the silvery white appearance
of that iron. Its specific gravity is from 5.95 to 6.72. It has
native steel intermingled in it, but contains no nickel, or any other
alloy.
Major Barrall has only been to the place where this iron occurred
_once_, and no other person has ever been to the place, or knows
where it is.—_Silliman’s Journal_, xii. 154. [p225]
7. _Native Argentiferous Gold_.—M. Boussingault, who has had the
opportunity of examining numerous specimens of argentiferous native
gold from the Columbian mines, thinks that they are atomic; he has
found 1 atom of silver united to 2, 3, 5, 6, and 8 atoms of gold,
and considers it probable that the other combinations to complete
the series may occur. He has assumed 24.86 as the number for gold,
and 27.03 as the number for silver. The following are some of the
experimental results:—
_Native Gold of Marmato_.—Pale yellow octoedral crystals:
Gold 73.45 3 atoms 73.40
Silver 26.48 1 " 26.60
Loss 00.07
_Native Gold of Titiribi:_
Gold 74.00 3 atoms 73.40
Silver 26.00 1 " 26.60
_Native Gold of Malpaso_.—Yellow irregular flattened grains:
Gold 88.24 8 atoms 88.04
Silver 11.76 1 " 11.96
_Native Gold of Rio-Sucio_.—Deep-coloured large irregular grains:
Gold 87.94 8 atoms 88.04
Silver 12.06 1 " 11.96
_Native Gold of the Otra Mina_.—Pale yellow octoedral crystals:
Gold 73.4 3 atoms 73.40
Silver 26.6 1 " 26.60
_Native Gold of Guamo_.—Brass-yellow indeterminate crystals:
Gold 73.68 3 atoms 73.40
Silver 26.32 1 " 26.60
_Native Gold of Llano_.—Small flattened grains—reddish:
Gold 88.58 8 atoms 88.04
Silver 11.42 1 " 11.96
_Native Gold of Baja_.—Porous:
Gold 88.15 8 atoms 88.04
Silver 11.85 1 " 11.96
_Native Gold of Ojas-Anchas_.—Yellowish red plates:
Gold 84.5 6 atoms 84.71
Silver 15.5 1 " 15.29
_Native Gold of Trinidad, near Santa Rosa de Osos_.—A solid piece
of 50 grains:
Gold 82.4 4 atoms 82.14
Silver 17.6 1 " 17.86
_Native Gold of Transylvania (Europe)_.—Pale yellow cubic crystals:
Gold 64.52 2 atoms 64.77
Silver 35.48 1 " 35.23
_Native Gold of Santa Rosa de Osos_.—A mass weighing 710 grains:
Gold 64.93 2 atoms 64.77
Silver 35.07 1 " 35.23
M. Boussingault has remarked a singlar deficiency in the [p226]
specific gravity of the native alloys of gold and silver when
compared with calculation, or with the results obtained from an alloy
similar in composition prepared by fusion; thus the native gold of
Marmato has a specific gravity of 12.666, whereas, by calculation, it
ought to be 16.931. The gold of Malpaso, by experiment, is 14.706, by
calculation, 18.223, and by fusion, 18.1. The gold of Santa Rosa, by
experiment, is 14.149, and by calculation, 16.175. This difference,
M. Boussingault says, is not due to porosity in the native gold, as
he has observed it in the granular and fine varieties, but a peculiar
character of the metal in this state. Such an enormous difference,
however, is one that can be admitted only upon repeated experimental
proofs, made in the most unexceptionable manner; and, considering
that it is only in some of the metals that any permanent difference
in specific gravity can be established, and even with them to but a
small extent, would be a fact so important as to be worth extreme
trouble in the verification.—_Annales de Chimie_, xxxiv. 408.
8. _Prothéeïte—a new Mineral_.—This mineral was discovered in 1826,
at Rothenkoph, in the valley of Zillerthal, Tyrol. It occurs in
rectangular prisms, generally without distinct summits, and rough
at both ends. The angles are very seldom truncated, the faces are
striated longitudinally. The crystals are of various sizes, some
being very small, but they have occurred 5 inches in length, and two
in width; the longitudinal fracture is lamellar, the cross-fracture
conchoidal. The substance is usually fissured, nearly opaque in large
specimens, translucent or diaphanous in small masses. Its colour is
crysolite green or white, or between the two; its lustre between that
of glass and the diamond; it is heavy; a good conductor of heat;
hard enough to scratch glass; infusible before the blowpipe; highly
electric by friction. The white crystals have a fibrous texture,
which, as well as the colour, seems the result of decomposition. When
cut and polished, the mineral assumes a great variety of aspects;
the green parts then resemble the finest crysolites, but the fibrous
white parts, when cut of a round form, present one or two reflections
on a transparent ground which move as the stone is moved, just like
those from the cat’s eye; these reflections are very brilliant, and
are accompanied by numerous iris colours, which move like those on
the opal. This phenomenon is often observed in the rough stone,
which, when exposed to light, exhibit certain deep red tints of a
cupreous colour, and metallic lustre on all the faces.—_Bull. Univ._
B. xi. 42.
9. _Volcanic Bisulphuret of Copper_.—M. N. Covelli, during his
examinations of Mount Vesuvius, has observed some particular actions
going on, especially in the fumeroles on the eastern side of the
mountain, and within the crater. Speaking of the former, he says,
“Here there are fumeroles in which pure chloride of lead [p227]
sublimes into white and yellow crystallizations, which fusing in the
hotter places form nacres, gum, and stalactites. In many parts the
sulphuretted hydrogen, evolved within the fumeroles, reacts on the
chloride, and forms sulphuret of lead, dispersed in small scales
through the scoria. Other fumeroles produce very thin scales of the
black oxide of copper; these are very brilliant, metalloidal, and
flexible, and are produced by the action of the vapour of water
at a red heat on the chloride of copper, which may be observed on
disturbing the fumeroles. Here and there the reaction of aqueous
vapour on the perchloride of iron produces metalloidal scales of
the peroxide of iron; whilst further on, the same vapour, acting
on mixtures of the two chlorides, produces oligiste iron in small
crystals, aggregated on the scoria. The muriatic acid resulting
from these actions, and the sulphuric acid which is formed by the
decomposition of hydrosulphurets and sulphates, attack the iron,
lime, copper, alumine, potash, &c., in the lavas and scoria, and
hence result a number of other productions which line the passages of
the fumeroles”.
M. Covelli descended into the crater, until within 300 feet of the
edge of the large eastern opening, from which the great current of
lava flowed in 1822. Here the fumeroles presented the most beautiful
crystallizations of sulphate of lime and sulphur. On examining the
scoria they were found incrusted and covered with a substance,
having all the shades of colour belonging to blue, green, and black.
Sometimes it resembled a spider’s web in appearance, sometimes
soot deposited in the cavities of the scoria. Many specimens were
collected, and also a portion of water condensed from the vapours
which issued forth, and which evidently contained sulphuretted
hydrogen and muriatic acid. The temperature of the vapour was as high
as 85° C., in some places, and even up to 90°, at half a foot beneath
the surface.
The water being examined was found to contain only a little
sulphuretted hydrogen, and a little muriatic acid. The black
substance was soon ascertained to be a pure sulphuret of copper.
Being analyzed, 100 parts yielded 32 parts of sulphur, and 66 of
copper, a loss of two parts being incurred, which accords very nearly
with the composition of the bi-sulphuret of copper. The blue and
bluish-green substances were found to be mixtures of this sulphuret
with sulphate and hydro-sulphuret of copper.
M. Covelli concludes that this substance has been formed by the
action of sulphuretted hydrogen on the sulphate and muriate of copper
evolved by these fumeroles; and observes, that its composition
accords with such an opinion, the deutoxide being that which forms
the Vesuvian cupreous salts.—_Ann. de Chimie_, xxxv. 105.
10. _Fall of the Lake Souwando in Russia_.—This lake, situated in
the parish of Sakkola, in the Russian government of Wibourg, and
surrounded by the lands of the Barons Friedrichs, was near [p228] 40
versts in length, and had the form of a Γ, or Greek G. Before the
year 1818, it was separated from the lake of Ladoga by an interval
about a verst in width, called Taipale, on which was a sandy hill;
its waters flowed into the river Wuoxa, which united the lakes of
Saima and Ladoga. On the 14th May, 1818, the waters of the lake
Souwando, increased by the thaw and the tempests, overcame the
natural dyke at the foot of the lake, threw down the hill of sand,
rapidly flowed into the lower lake, carrying away all the surrounding
grounds, and for ever destroyed the barrier which had previously
separated them. A chapel and a countryman’s house were carried away
with the pastures and meadows; the waters of the lower lake were much
disturbed, and the surface covered with ruins. The level of the lake
Souwando fell 12-1/2 archines, and its length is now only 15 versts.
Its waters no longer flow off by the Wuoxa, but pass into the lower
lake by several falls through a deep canal. The land which has been
uncovered by the water is already cultivated, and the beauty of the
surrounding country said to be increased.—_Bull. Univ._, F. x. 133.
11. _Vegetable Torpor observed in the Roots of the Black
Mulberry-tree_.—A very old mulberry-tree was broken into four
quarters by the wind in 1790. Two of the quarters were destroyed,
the other two remained growing for a few years, but the last of
them was removed in 1802. An elder-tree grew in the place of the
mulberry-tree, without doubt from berries which had fallen into
the middle of the old trunk of the latter. This elder-tree died in
1826, and at the time of its languishing about a dozen of mulberry
shoots started forth to the day. M. Dureau de la Malle ascertained
that these did not spring from seeds, but from the roots of the old
mulberry-tree, which had thus lain in the ground in an apparently
inactive state, for 24 years, to send forth shoots at last.—_Ann. de
Sciences Nat._ ix. 338.
12. _Method of increasing the Odour of Roses_.—For this purpose,
according to the author of the method, a large onion is to be planted
by the side of the rose tree in such a manner that it shall touch
the foot of the latter. The roses which will be produced will have
an odour much stronger and more agreeable than such as have not been
thus treated, and the water distilled from these roses is equally
superior to that prepared by means of ordinary rose leaves.—_Œkonom.
Neuigk._;—_Bull. Univ._
13. _Pine Apples_.—A great improvement may be made in keeping pine
apples by twisting off their crowns, which are generally suffered to
remain and to live upon the fruit till they have sucked out all the
goodness. It will be very easy for fruiterers to keep a few crowns by
them in water, which can be pegged or stuck on with dough, for show,
when the fruit is served up, or artificial ones [p229] may be made. A
pine apple will keep for a long time when its crown is removed, and
will also be greatly improved in flavour, for the more aqueous parts
of the fruit gradually evaporate, and leave it much more saccharine
and vinous in its flavour; which natural process is totally destroyed
by the vegetation of the crown, just upon the same principle that an
onion or carrot loses its flavour when it begins to sprout in the
spring.
14. _Mode of Condensing and Preserving Vegetable Substances for
Ships’ Provision, &c._—The quantity of liquid matter which enters
into the constitution of vegetables is very great; when they are
deprived of it their bulk is very trifling. That preparation of
animal food called _pemmican_, in which six pounds of meat are
condensed into the space of one, is mainly effected by abstracting
all the fluid from it. Vegetables may be treated in the same way: let
them undergo the process of boiling over a fierce wood fire, so as
to preserve their colour when _completely_ cooked; grind them into
a complete pulp by some such means as are used to crush apples for
cider, &c.; then let them be subjected to the action of the press,
(being first put into hair bags, or treated as grapes are in wine
countries,) till all the fluid matter is separated from them; the
remainder of their substance becomes wonderfully condensed, and as
hard as the _marc_ from the wine press. Then let it be rammed hard
into carefully glazed air-tight jars, (or tin cases, if preferred,)
and subjected to the Appertian process for preserving animal and
vegetable matters, (well known, by-the-by, to our grandmothers, who
preserved gooseberries in this way from time immemorial.) If jars
are used, they may be sufficiently secured by having two pieces of
bladder tied successively over them; when the air within is absorbed
by heating the inclosed substance, their surface becomes concave by
the pressure of the atmosphere, and as long as it remains in this
state the matter within is safe. If it should be thought requisite to
preserve the flavour of the vegetables entire, an extract should be
made from the expressed liquid, and added to the _marc_. But spinage,
cabbage, and many others, have abundance of flavour in them in their
dry state without this addition. The preparation of the vegetable
matter for use is accomplished by adding a sufficient quantity of
milk, water, gravy, lime juice, &c., to the _marc_, and warming it
up. Let the government, and the dealers in ships’ provision, look to
this; a sufficient quantity of this _vegetable pemmican_ would be
the greatest luxury to a ship’s crew, and render the scurvy utterly
obsolete. It is worthy of remark, that the most irritable stomach is
not offended by vegetables treated in this way.
15. _Rewards for the Discovery of Quinia, and for Lithotrity_.—The
Académie des Sciences has adjudged a prize of 10,000 francs to MM.
Pelletier and Caventou, for their discovery and introduction [p230]
into use of sulphate of quinia; and another prize of 10,000 francs to
M. Civiale, for having been the first to practise lithotrity on the
living body, and for having successfully operated by his method on a
great number of persons afflicted with the stone in the bladder.
16. _Upon the Gaseous Exhalations of the Skin_.—M. Collard de
Martigny, having experimented on this subject, has obtained results
which tend to reconcile the differences existing between previous
observers. The Count de Milly first announced, in the year 1777, that
an aëriform fluid escapes in great quantity from the surface of the
skin, and he considered the gas as carbonic acid. Cruikshank, Jurene,
and Abernethy participated in this opinion. Ingenhouz, on the other
hand, maintained that the air so secreted was azote. M. Frousset
adopted the opinion of Ingenhouz, and endeavoured to confirm it by
experiments. Lastly, Priestley and Fontana questioned the reality of
a gaseous exhalation from the skin; and Fourcroy positively denied it.
From the experiments of M. Collard de Martigny, he deduces,
i. That a gaseous exhalation really takes place from the skin.
ii. This exhalation is not morbid: it is observable in health.
iii. It is composed of carbonic acid and azote, in very variable
proportions. The following experiment was frequently made. The
bubbles of air which are disengaged from the skin were received into
a funnel, the top of which was closed: they were then passed into a
graduated tube, and agitated with a solution of potash. The height
to which the solution rose in the tube indicated the quantities of
carbonic acid that had been absorbed. All these operations were made
at the same temperature and pressure. Neither hydrogen nor oxygen gas
were discovered in this air.
iv. It does occur continually; but very often we may vainly attempt
to discover it, which has been the cause of error in the results of
Priestley, Fontana and Fourcroy. It is especially suspended after
exercise long continued in the middle of the day, or immediately
after taking an abundant meal. Sometimes it is suspended without any
apparent cause.
v. The quantity also is very variable; but it was observed to be
constantly in an inverse ratio to the cutaneous absorption.
vi. The proportions of the two gases vary very much, and sometimes
the exhaled gas consists almost entirely of azote: in other instances
the predominance of carbonic acid is so great that it appears to be
the only product.—_Med. Rep._, N. S. v. 75.
17. _Effects of Galvanism in Cases of Asphyxia by submersion_.—M.
Leroy d’Etioles has addressed a letter to the Académie de Médecine,
in reply to an assertion made by M. Thillaye respecting the inutility
of galvanism in cases of asphyxia. The former says, that when a
short and fine needle is inserted in the sides of the body between
the eighth and ninth ribs so as to come in contact with [p231] the
attachment of the diaphragm, and then the current of electricity from
25 or 30 pair of inch plates passed through them, that the diaphragm
immediately contracts, and an inspiration is effected. Upon breaking
the communication, and again completing it, a second inspiration is
occasioned, and by continuing these means, a regular respiration
may ultimately be occasioned. This power thus applied has always
succeeded with him in experiments on drowned animals.—_Bull. Univ._,
C. xi. 213.
18. _Recovery from Drowning_.—M. Bourgeois had occasion accidentally
to give assistance in a case where, after a person had been twenty
minutes under water, he was taken out, and by a very common but
serious mistake, carried with his head downwards. The usual means
were tried unremittingly, but unsuccessfully, for a whole hour, but
at the end of that time a little blood flowed from a vein that had
been opened, and a ligature being placed on the arm, ten ounces of
blood were withdrawn: the circulation and respiration were then
gradually re-established, horrible convulsions, and a frightful state
of tetanus coming on at the same time; copious bleeding was again
effected, after which a propensity to sleep came on: a third bleeding
the following morning was followed by the recovery of the patient.
Hence M. Bourgeois concludes that the means of recovering a drowned
person should never be abandoned until the decomposition of the body
has commenced.—_Bull. Univ._, C. xi. 213.
19. _Preservation of Cantharides_.—It is stated by M. Farines that
the active part of cantharides exists only in the soft organs of the
insect; that these are the parts which are attacked by a species of
acarus, and that in this way the cantharides are injured. Camphor
has no power of preventing the attacks of the acarus; but M. Farines
believes that pyroligneous acid will be found effectual, and proposes
to prepare cantharides with it, and even to kill them at the time
when they are collected by submersion in it.
20. _Chloride of Lime in cases of Burns_.—The good effect of chloride
of lime in cases of burns is confirmed by the experience of M.
Lisfranc. He has applied it in many cases of that kind, sometimes
immediately after the accident, sometimes after the application of
emollient cataplasms. Lint is moistened in a solution more or less
strong of chloride of lime, and then applied to the place, being
covered over with waxed cloth. The cure has been singularly hastened
under its influence and in one case where almost the whole of the
lower limbs, the arms and face, had been burnt, the use of the
chloride recovered the patient from the stupor into which he had
fallen at the end of four days, and a perfect recovery was effected
two months after the accident.—_Bull. Univ_., C. xi. 77. [p232]
21. _Cure of Nasal Polypi_.—Dr. Primus of Babenhausen asserts, that
the saffronised tincture of opium (of the Prussian Pharmacopœia)
possesses the property of gradually destroying nasal polypi when
applied to them. Certain cures, which have been thus effected, have
already been published, and a striking one occurred in January, 1826.
A man, 46 years of age, had one in each nostril. The tincture was
applied several times a day to the bases of the polypi, by means of a
small hair-brush or lint roll. In eight days the tumours had assumed
a paler appearance, and lost a little in volume; a serous secretion
from the nose, which had existed for a long time, was diminished, and
the pituitary membrane had acquired a more lively tint, as if in a
sub-inflammatory state. The application was continued, the tumours
continued to decrease, and at the end of three weeks had entirely
disappeared.—_Mediz. Chirurg. Zeitung_, 1826, p. 13.
22. _Bite of the Viper_.—M. Jacopo Sacchi, of Barzio in Valsasina,
having had occasion to take charge of some cases in which injury had
been inflicted by the bite of a viper (Coluber Berus), transferred
his observations upon them into the hands of Professor Paletta. From
these it appears that ammonia, recommended by Dr. Mangili, in 1813,
although an excellent remedy in many cases, is by no means sufficient
in all, but must occasionally be seconded by every possible means.
Although sometimes nature alone has power sufficient to overcome
the bite of a viper, yet, at other times, the injury is so great
and sudden as to resemble the effects of hydrocyanic acid. In these
cases he recommends that the patient should be put into a hot bed
covered with woollen clothes, and the most powerful sudorifics with
some tonics administered internally. Friction should be applied all
over the body, and at the same time the wounds are to be enlarged,
cupping-glasses applied, and tow, dipped in ammonia, applied to the
spot.
23. _Experiments on the Poison of the Viper_.—M. Desaulx confirms
the fact that dogs can swallow with impunity even large quantities
of the poison of vipers. He observed also that when this poison
was withdrawn from the vesicles it soon lost in power, and
after a certain time became inert: a portion ten days old being
introduced into a fresh wound of a living animal, only caused slight
tumefaction on the part. Mangili, on the contrary, found it, when
hermetically sealed up, to retain its virulence for many months. The
species of viper from which M. Desaulx obtained his poison is not
mentioned.—_Bull. Univ._ C. xi. 142.
24. _Destruction of Moles_.—The following method of destroying moles
is asserted, by the Count de Boisseulh, to be excellent. Grounds much
infested by these animals have been perfectly freed from them by
means of it. A number of worms must be procured, killed, and powdered
with pulverised vomica-nut; the whole is to [p233] be mixed and left
for twenty-four hours. The mole-tracks are then to be opened, and two
or three of these worms placed in each hole. If the meadow is large,
they cannot be placed in every hole; but by multiplying them as much
as possible, a good result is sure to be obtained.—_Ann. de Agricul.
de la Charente_.
25. _On growing Salad-herbs at Sea_.—On long sea-voyages, whatever
esculent roots, or fruit, or whatever vegetable essences may be
stowed in the steward’s stores, whether for the use of the officers
or crew, nothing can be a greater treat to the former, especially
within the tropics, than a dish of fresh salubrious salad-herbs. The
want of such an addition to the ordinary fare on board a ship has
often been a cause of disease, and misfortune, and even death!—it
is needless, therefore, to insist on the usefulness, or to state
the antiscorbutic, and consequently sanatory qualities, of fresh
vegetables in such situations; and however limited the means to
supply such a want as is described below, yet, as it may be highly
useful to convalescents, and in individual cases, the publication may
not be deemed altogether valueless.
Provide one, two, or three deal boards, made of well-seasoned inch
stuff, sixteen inches square, with a ledge all round, rising one
inch above the smooth surface of the board; and as it is intended to
hold water, the ledges must be closely and neatly fitted: at each
corner a nail, or small hook, should be placed, with strings tied
into a loop above, by which the board may be slung in the necessary
horizontal position; a thin covering-board, made of the same material
and dimensions, is also necessary, and which will serve for all the
boards.
Pieces of the _thickest_ flannel must be had for each board, cut so
as to fit exactly within the ledges. These flannels require to be
well soaked, and repeatedly washed in boiling water, before they can
be used, to discharge from them whatever is pernicious to vegetation
as they come from the manufacturer’s hands.
The board and flannel thus prepared, dip the flannel in water, and
place on the boards; sow the seeds pretty thick and regularly;
sprinkle them lightly with the hand, till all are moistened and the
flannel completely saturated; in which state it should always be kept
during the growth of the plants. Too much water floats the seeds when
first put on, and are thereby shifted from their places by the motion
of the ship. The cover-board must now be put on, and the whole hung
up in its place. The use of this board is to assist the vegetation of
the seeds, which it will do sufficiently in the course of twenty-four
hours; after which it may be laid aside.
The board must be frequently examined, and when the moisture thereon
is diminished by evaporation, or imbibed by the crop, a supply must
be given, just enough to keep the flannel in the proper saturated
state.
In six or seven days the crop will be (if the weather has been
favourable) two inches high,—it is then fit for use. The produce
[p234] of one board yields about as much as will fill a middle-sized
salad-bowl, and when dressed up with the usual condiments of onion,
salt, vinegar, and oil, a most agreeable salad will be composed, and
a most acceptable treat to the guests at the captain’s table.
It is necessary that the board, as well as the flannel, be scalded,
well washed, and dried in the sun, before it can be used again;—and
as one board yields one crop per week, two, or even three boards may
be used at the same time, in order to secure a regular supply. Larger
boards are not so convenient, because they can only be hung in some
by-corner of a cabin, quarter-gallery, or state-room, where they may
not only be out of the way, but out of the sun and currents of air.
The herbs suitable to be raised in this way are, radish, mustard, and
common garden-cress. The two first answer best within the tropics;
the last does not, being too delicate and diminutive;—but this does
very well when the ship is no nearer the equator than thirty degrees
of latitude. One peck of radish, another of mustard, and two quarts
of cress, will be sufficient for an India and China voyage,—a supply
of which may be had in China. I. M.
26. _Chinese Method of fattening Fish_.—The Chinese are celebrated
for their commercial acumen, indefatigable industry, and natural
adroitness,—in making the most of every gift of nature bestowed
on their fertile country. Useful as well as ornamental vegetables
engross their every care; and animals which are the most profitably
reared, and which yield the greatest quantity of rich and savoury
food, are preferred by them for supplying their larders and stews.
Their _hortus dietetica_ would form a considerable list; and
though they do not use such a variety of butcher’s meat and fowl
as Europeans do, yet in the articles of pork, geese, and ducks,
they surpass, in the use of fish they equal, us, and in their
domestication and management of them they excel all other nations.
A few observations on their _piscinas_, or fish-stews, is the design
of this paper; not merely as an historical description, but as an
object for imitation in this or any other country.
For twenty or thirty miles round Canton, and as far as the eye can
reach on each side of the river on which that city stands, the
general face of the country appears nearly a level plain, with but
little undulation of surface. The level is, however, richly studded
with beautiful hills, which diversify the landscape, and seem to rise
out of the plain so abruptly, that they form the most picturesque
features, united with the most pleasing combinations. The soil of
the plain consists of a pure alluvial earth of great fertility and
depth, and very retentive of water; which, by the by, is a proof
that, notwithstanding their claim to high chronological antiquity,
the waters of the deluge remained much longer (perhaps for ages) on
this portion of the continent of Asia, than it did in the interior:
and the circumstance of many of their hills being cultivated to
the [p235] very top, their numerous water-plants, and their almost
amphibious habits as to their domiciles, are still further proofs
that the country was, once, more of an aquaium than it now is.
Hence the facility of making canals, which are their high-roads (as
wheel-carriages, and beasts of draught, are too expensive appendages,
for the systematic economy of the celestial empire!) and hence the
ease with which a pond may be made in any otherwise useless corner.
Such tanks, or ponds, are generally met with in market-garden
grounds, where they serve the double purpose of a reservoir, and a
stew for rearing and fattening fish.
When a pond is made for this purpose, and filled with water, the
owner goes to market, and buys as many young store-fish as his pond
can conveniently hold; this he can easily do, as almost all their
fish are brought to market alive. Placed in the stew, they are
regularly fed morning and evening, or as often as the feeder finds it
necessary; their food is chiefly boiled rice, to which is added, the
blood of any animals they may kill, wash from their stewing-pots and
dishes, &c., indeed any animal offal or vegetable matter which the
fish will eat. It is said, they also use some oleaceous medicament
in the food, to make the fish more voracious, in order to accelerate
their fattening; but of this the writer could obtain no authentic
account.
Fish so fed and treated, advance in size rapidly, though not to any
great weight; as the kind (a species of perch) which came under
observation, never arrive at much more than a pound avoirdupois; but
from the length of three or four inches, when first put in, they grow
to eight or nine in a few months, and are then marketable. Drafts
from the pond are then occasionally made; the largest are first taken
off, and conveyed in large shallow tubs of water to market: if sold,
well; if not, they are brought back and replaced in the stew, until
they can be disposed of.
This business of fish-feeding is so managed that the stock are
all fattened off about the time the water is most wanted for the
garden-crops. The pond is then cleaned out, the mud carefully saved,
or spread as manure,—again filled with water, stocked with young fry,
and fed as before.
An intelligent Chinaman, from whom the writer had the above detail,
and who showed him as much of the process as could be seen during a
residence of three months, declared as his belief, that a spot of
ground, containing from twenty to thirty square yards, would yield a
greater annual profit as a stew, than it would in any other way to
which it could possibly be applied.
That fish may be tamed, suffer themselves to be caressed, and even
raised out of their natural element by the hand, has been long known
to naturalists; witness the famous old carp formerly in the pond
of some religious house at Chantilly, in France, with many other
instances on record. But it is probable no people has carried the art
of stew-feeding fish, and practising it as a profitable concern, to
such lengths, as is done by the Chinese at this day. I. M. [p236]
METEOROLOGICAL DIARY for the Months of June, July, and August, 1827,
kept at EARL SPENCER’s Seat at Althorp, in Northamptonshire.
The Thermometer hangs in a North-eastern Aspect, about five feet
from the ground, and a foot from the wall.
+------------------------------------------------------+
| FOR JUNE, 1827. |
+-------------+--------------+-------------+-----------+
| | Thermometer. | Barometer. | Wind. |
| +------+-------+------+------+-----+-----+
| |Lowest|Highest|Morn. |Eve. |Morn.|Eve. |
+----------+—+------+-------+------+------+-----+-----+
|Friday | 1| 47 | 65 | 29.50| 29.50| SW | SW |
|Saturday | 2| 42 | 62.5 | 29.60| 29.43| S | WbS |
|Sunday | 3| 44 | 63 | 29.67| 29.67| W | W |
|Monday | 4| 44 | 62 | 29.70| 29.79| W | W |
|Tuesday | 5| 47 | 59 | 29.70| 29.59| W | W |
|Wednesday | 6| 47 | 58 | 29.47| 29.60| W | NW |
|Thursday | 7| 43 | 60 | 29.78| 29.88| W | NW |
|Friday | 8| 36 | 63 | 30.02| 30.07| NW | W |
|Saturday | 9| 45 | 72 | 30.13| 30.17| W | W |
|Sunday |10| 48 | 68.5 | 30.17| 30.10| NE | NE |
|Monday |11| 46 | 70.5 | 30.09| 30.02| NE | NE |
|Tuesday |12| 46 | 66 | 30.02| 30.02| NE | NE |
|Wednesday |13| 51 | 65 | 30.02| 29.94| NE | NE |
|Thursday |14| 48 | 65 | 29.89| 29.78| NE | NE |
|Friday |15| 51 | 60 | 29.70| 29.60| NE | NE |
|Saturday |16| 52 | 71 | 29.60| 29.57| NE | S |
|Sunday |17| 54 | 73 | 29.66| 29.66| WSW | W |
|Monday |18| 54 | 72.5 | 29.78| 29.79| W | W |
|Tuesday |19| 50 | 68 | 29.79| 29.69| W | W |
|Wednesday |20| 48 | 65 | 29.65| 29.67| W | WbS |
|Thursday |21| 44 | 66.5 | 29.70| 29.73| SW | W |
|Friday |22| 43 | 64 | 29.80| 29.88| W | W |
|Saturday |23| 48 | 63 | 29.90| 29.94| W | W |
|Sunday |24| 43 | 66.5 | 29.94| 29.97| W | W |
|Monday |25| 49 | 66 | 29.97| 29.90| WNW | NNW |
|Tuesday |26| 46 | 69 | 29.90| 29.86| W | WbS |
|Wednesday |27| 53.5| 67 | 29.80| 29.69| SW | SW |
|Thursday |28| 56 | 66 | 29.48| 29.46| SW | SW |
|Friday |29| 56 | 70 | 29.46| 29.53| SW | SW |
|Saturday |30| 52 | 72 | 29.59| 29.68| W | W |
+----------+—+------+-------+------+------+-----+-----+
+------------------------------------------------------+
| FOR JULY, 1827. |
+-------------+--------------+-------------+-----------+
| | Thermometer. | Barometer. | Wind. |
| +------+-------+------+------+-----+-----+
| |Lowest|Highest|Morn. |Eve. |Morn.|Eve. |
+----------+—+------+-------+------+------+-----+-----+
|Sunday | 1| 55 | 69 | 29.60| 29.63| E | SW |
|Monday | 2| 49 | 66.5 | 29.70| 29.60| S | SW |
|Tuesday | 3| 49 | 69 | 29.63| 29.78| WbS | WbS |
|Wednesday | 4| 48 | 73 | 29.99| 29.99| W | WbS |
|Thursday | 5| 58 | 67 | 30.06| 30.20| NE | NE |
|Friday | 6| 42 | 70 | 30.29| 30.27| E | WNW |
|Saturday | 7| 55 | 75 | 30.27| 30.26| WNW | WNW |
|Sunday | 8| 53 | 74 | 30.26| 30.21| WbN | WbN |
|Monday | 9| 54 | 73.5 | 30.19| 30.08| W | W |
|Tuesday |10| 54 | 72 | 30.02| 29.87| W | WbN |
|Wednesday |11| 55.5| 67 | 29.90| 29.98| NW | W |
|Thursday |12| 45 | 68 | 30.02| 30.04| W | ENE |
|Friday |13| 44 | 73 | 30.06| 30.04| E | E |
|Saturday |14| 46.5| 71.5 | 30.04| 30.00| ESE | E |
|Sunday |15| 45 | 71 | 29.98| 29.91| E | NE |
|Monday |16| 47 | 71.5 | 29.91| 29.90| E | E |
|Tuesday |17| 46.5| 77 | 29.90| 29.88| SE | WbS |
|Wednesday |18| 57 | 72 | 29.83| 29.87| WSW | W |
|Thursday |19| 51 | 68 | 29.87| 29.71| W | SW |
|Friday |20| 57 | 69 | 29.59| 29.62| W | W |
|Saturday |21| 50 | 69 | 29.77| 29.80| W | W |
|Sunday |22| 45 | 64 | 29.82| 29.80| ESE | SE |
|Monday |23| 57 | 73 | 29.83| 29.88| EbS | W |
|Tuesday |24| 58 | 75 | 29.90| 29.89| W | WbS |
|Wednesday |25| 60 | 72 | 29.82| 29.82| SW | WNW |
|Thursday |26| 46 | 69.5 | 29.92| 29.78| W | SSW |
|Friday |27| 54 | 74 | 29.90| 30.00| W | W |
|Saturday |28| 58 | 79 | 30.00| 30.02| W | W |
|Sunday |29| 54 | 78 | 30.04| 29.92| ESE | SE |
|Monday |30| 65 | 75 | 29.62| 29.80| SSE | W |
|Tuesday |31| 52 | 72.5 | 30.03| 30.10| W | W |
+----------+—+------+-------+------+------+-----+-----+
+------------------------------------------------------+
| FOR AUGUST, 1827. |
+-------------+--------------+-------------+-----------+
| | Thermometer. | Barometer. | Wind. |
| +------+-------+------+------+-----+-----+
| |Lowest|Highest|Morn. |Eve. |Morn.|Eve. |
+----------+—+------+-------+------+------+-----+-----+
|Wednesday | 1| 51 | 72 | 30.04| 29.95| W | |
|Thursday | 2| 46 | 77.5 | 29.82| 29.67| W | |
|Friday | 3| 56 | 74 | 29.60| 29.50| SW | W |
|Saturday | 4| 58 | 71 | 29.48| 29.63| SW | W |
|Sunday | 5| 53 | 66 | 29.91| 30.06| W | NE |
|Monday | 6| 51 | 67.5 | 30.13| 30.18| NE | ENE |
|Tuesday | 7| 42 | 70 | 30.18| 30.10| E | E |
|Wednesday | 8| 40 | 68 | 30.04| 29.98| E | E |
|Thursday | 9| 41 | 70.5 | 29.93| 29.80| EbN | SE |
|Friday |10| 57 | 70 | 29.60| 29.48| SW | W |
|Saturday |11| 47 | 66 | 29.48| 29.44| W | W |
|Sunday |12| 50 | 62 | 29.55| 29.67| WSW| WNW |
|Monday |13| 46 | 67 | 29.76| 29.73| W | WbS |
|Tuesday |14| 51 | 70 | 29.53| 29.43| SW | SW |
|Wednesday |15| 60 | 68 | 29.22| 29.25| SE | WbS |
|Thursday |16| 51 | 67 | 29.30| 29.36| S | NE |
|Friday |17| 56 | 68 | 29.60| 29.76| NE | NE |
|Saturday |18| 54 | 60 | 29.87| 29.87| NE | NE |
|Sunday |19| 48 | 65 | 29.89| 29.90| NE | NE |
|Monday |20| 42.5| 59.5 | 29.90| 29.90| NE | NW |
|Tuesday |21| 56 | 67.5 | 29.90| 29.95| NE | NE |
|Wednesday |22| 51 | 59 | 30.03| 30.10| N | NW |
|Thursday |23| 48 | 68 | 30.20| 30.20| NW | NW |
|Friday |24| 52 | 63 | 30.14| 30.08| WNW | WbN |
|Saturday |25| 49 | 60 | 30.00| 30.04| WNW | W |
|Sunday |26| 44 | 58 | 30.08| 30.08| NW | N |
|Monday |27| 42 | 67 | 30.12| 30.16| N | NW |
|Tuesday |28| 47 | 64 | 30.16| 30.16| W | NW |
|Wednesday |29| 50 | 63 | 30.24| 30.24| NNE | NW |
|Thursday |30| 47 | 63 | 30.18| 30.07| W | W |
|Friday |31| 52 | 63 | 30.12| 30.20| N | NE |
+----------+—+------+-------+------+------+-----+-----+
TO OUR READERS AND CORRESPONDENTS.
The pages of this Journal are impartially open to all communications
upon the subjects of Science, Scientific Literature, and the Arts: it
is requested they may be forwarded to the Editor one month previous
to the publication of each number.
We shall be happy to receive papers from Provincial Scientific
Societies, and to publish them either on the part of the Society, or
of their respective authors.
Papers deemed unfit for this publication, will be immediately
returned to the source whence we received them, with our reasons for
their return.
* * * * *
The letters signed B. and T. R. S. we have thought it prudent to
suppress for the present.
* * * * *
Several books have reached us for notice in this Journal; but unless
they are sent earlier in the Quarter, we cannot insure attention to
them.
* * * * *
We have been favoured with communications from Mr. Swainson, Dr.
Littledale, Mr. Rose, and E. Z., which we are obliged to postpone.
* * * * *
A letter from a “Member of the Zoological Society,” reached us too
late for the purpose it was intended to answer. We fear we shall not
agree with him in opinion, but perhaps his _second communication_ may
clear up the difference.
* * * * *
We presume that “A Mechanic” will find the information he requires in
Mr. Farey’s account of the Steam Engine.
* * * * *
“An old Subscriber” is much in error—the _proceedings_ he alludes
to are copiously given in contemporary monthly publications; if
therefore we followed his advice, our information would be stale. The
motives he alludes to are out of the question.
* * * * *
We cannot give “A Vapourer” any authentic information respecting the
Steam Carriage, nor do we hear that the Gas Engine has advanced.
ROYAL INSTITUTION OF GREAT BRITAIN,
Albemarle Street, _December 3, 1827_.
A COURSE OF SIX ELEMENTARY LECTURES ON CHEMISTRY, adapted to a
Juvenile Audience, will be delivered during the Christmas Recess,
by MICHAEL FARADAY, F.R.S., Corr. Mem. Roy. Acad. Sciences, Paris;
Director of the Laboratory, &c. &c.
_The Lectures will commence at Three o’Clock_.
_Lecture_ I. Saturday, December 29. Substances generally—Solids,
Fluids, Gases—Chemical affinity.
_Lecture_ II. Tuesday, January 1, 1828. Atmospheric Air and its Gases.
_Lecture_ III. Thursday, January 3. Water and its Elements.
_Lecture_ IV. Saturday, January 5. Nitric Acid or Aquafortis—Ammonia
or Volatile Alkali—Muriatic Acid or Spirit of Salt—Chlorine, &c.
_Lecture_ V. Tuesday, January 8. Sulphur, Phosphorus, Carbon, and
their Acids.
_Lecture_ VI. Thursday, January 10. Metals and their Oxides—Earths,
Fixed Alkalies and Salts, &c.
Non-Subscribers to the Institution are admitted to the above Course
on payment of One Guinea each; Children, 10_s._ 6_d._
The Weekly Evening Meetings of the Members of the Royal Institution
will commence for the ensuing Season, on Friday the 25th of January,
1828, at half past Eight o’Clock, and will be continued on each
succeeding Friday Evening, at the same hour, till further notice.
The Lectures will commence for the Season on Saturday the 2d of
February, at Three o’Clock, by WM. THOS. BRANDE, Esq., F.R.S. Lond.
and Edin., Prof. of Chemistry in the Royal Institution.
The Library of the Royal Institution is open for the use of the
Members and Subscribers every day on which the House of the
Institution is open; in Winter from Ten till Four, and from Seven
till Ten in the Evening; and in Summer from Ten till Five, and from
Seven till Ten in the Evening.
* * * * *
Mr. BRANDE and Mr. FARADAY will commence the Spring Course of their
Chemical Lectures and Demonstrations, in the Laboratory of the Royal
Institution, on Tuesday, the 12th of February, at Nine in the morning
precisely. A Prospectus may be obtained at the Institution, or of the
respective Lecturers.
* * * * *
_In the Press, and nearly ready for publication_,
A COLLECTION OF CHEMICAL TABLES, for the use of Practical
Chemists and Students, in Illustration of the Theory of Definite
Proportionals; in which are shewn the Equivalent Numbers of the
Elementary Substances, with the Weights and Volumes in which they
combine; together with the Composition of their most important
Compounds, and the Authorities for their Analysis.
By WILLIAM THOMAS BRANDE.
THE
QUARTERLY JOURNAL
OF
SCIENCE, LITERATURE, AND ART.
OCT.–DEC. 1827.
_On the Means generally used with the Intention of curing a
Stoop_.[37]
When the chest and the head fall forward, the most common method of
trying to correct the stoop is to put on some instrument by which the
shoulders and the head are held back. To operate upon the shoulders,
the common back-collar is applied, and to hold back the head, a
riband is brought over the forehead and fastened to the collar.
While these instruments are kept on, the figure looks straight,
though stiff and constrained; but the moment they are taken off,
both the head and the shoulders fall more forward, than before
their application. Many examples of the bad effect of artificially
supporting the head might be offered. The following, although
observed in the figure of a horse, is very demonstrative. When the
rein (called the bearing-rein), by which the head of a carriage-horse
is reared up, with the intention of giving him a showy figure, is
loosened, the head immediately falls forward, and the neck, instead
of preserving the fine arch that is so much admired, droops between
the shoulders. Looking to this effect, we should at first be inclined
to condemn the practice followed by horse-dealers, of reining up
the head of a young horse in the stable, by means of the apparatus
called a dumb-jockey. But on examining into this mode of fixing
the head, it will be found to operate on a different principle from
the bearing-rein. Instead of a [p238] simple bit, such as the horse
in harness can lean his head upon, without suffering pain, a bit,
calculated to tease and fret, is put into the young horse’s mouth.
To relieve himself from the irritation produced by this, and which
is increased by the constant pull of the elastic piece of iron to
which the rein is fastened, he curls up his neck, and thus brings
all the muscles of the back of the neck into strong action, instead
of allowing their power to be superseded by the artificial support
afforded by the bearing-rein to the horse in harness[38].
Many different contrivances, but all acting nearly on the same
principle as the _bearing-rein_, have been proposed as means for
obliging a girl to keep her head erect.
[Illustration]
There is one mode which, to a person ignorant of anatomy, seems to be
particularly well adapted for this purpose; but it is, in fact, more
objectionable than the plan of tying the head back with a riband. A
piece of lead, of some pounds weight, [p239] is slung over the back
in such a way that it must be supported by a riband put around the
head.
Although this contrivance prevents the head for a time from falling
forwards, its bad effects may be demonstrated. When the weight is on,
the muscles of the back of the spine are passive, while those on the
fore-part of the neck are necessarily brought into action to prevent
the head from being pulled too far back: this is easily proved; for
if we put the fingers on the sternal portions of the sterno-cleido
muscle, which, with the small muscles on the fore-part of the throat,
pull the head forwards, we shall feel them tense and in action. The
increased activity of the muscles on the fore part, and the passive
condition of those of the back, may be further exemplified by raising
the weight when the girl is not aware of our doing so; the head will
then be immediately poked forwards.
We have many opportunities of observing the incorrectness of the
principle on which all similar plans for the cure of a stoop have
been founded. For instance, porters who carry burthens on the back,
by the assistance of a band round the forehead, always stoop; while
those who carry baskets before them suspended by a band round the
back of the neck, are peculiarly erect. But the most remarkable
example of the effect of the head being pulled back by a weight hung
behind, is the condition of the women who carry salt in the streets
of Edinburgh, for they may be recognised as much by their miserable
Sardonic grin, which is caused by the constant excitement of the
platysma myoides muscle, as by their stoop.
Very annoying and even distressing consequences may ensue from any
system of treatment where a constant resistance to the muscles of
the fore-part of the neck is kept up. A gentleman had for many
years worn one of the collars invented by Mr. Chesher; after some
time, the muscles of the back became so weak, as to be incapable
of supporting the column, while those on the fore-part of the neck
were so disproportionately increased in strength, by the constant
resistance opposed to them by the strap passing from the suspending
rod under the chin, that whenever the strap was loosened, the chin
was forcibly drawn towards the chest. As the muscles of the back part
of the neck did not offer any counteracting resistance, the [p240]
windpipe was now pressed down, or almost doubled itself. As soon as
this took place (and it was almost immediate on the attempt to sit
up without the collar,) the patient was seized with such a sense of
suffocation, as to be obliged to throw himself on his back. As he was
able to breathe with ease as he lay on his back, his advisers were
led to believe that it was the weight of the head which pressed down
the windpipe. To counteract this pressure, various contrivances had
been proposed to support the head. Indeed, the patient himself was
so convinced, from what he had heard, that it was the weight of the
head which pressed down the windpipe, and so alarmed had he become
from the certainty of having a fit of suffocation when the head was
left unsupported, that there was much difficulty in persuading him
to believe that if the head could be made _heavier_, the sense of
suffocation would be relieved. He was at length induced, although
with great dread of the consequence, to allow about fourteen pounds
of shot to be placed on the top of his head. He was very much
alarmed, but it was highly gratifying to witness his surprise and
pleasure in finding that, instead of his head being weighed down, he
could support it, and could breathe with ease while in the upright
posture. The following is the principle on which this plan was
proposed:—the muscles of the back part of the neck had been brought
into such a state, that their ordinary stimulus was not sufficient
to excite them to the action necessary to counteract the efforts
of those on the fore-part of the neck, which had been evidently
increased in strength. The placing a weight on a certain spot on the
head formed an additional stimulus to the muscles of the back part
of the neck; a fact which the reader may prove by an experiment on
himself.
By proceeding on this principle, by combining a variety of exercises,
and by gradually diminishing the weight carried on the head, this
gentleman was soon able to walk and sit in a state of great comfort,
without being obliged to use any artificial support.
It is well known, that the neck-collars support almost the whole
weight of the head and shoulders by the strap which passes under
the chin. It must also have been observed, that the wearer very
frequently pushes down the head against the [p241] chin strap. In
this way, the muscles on the fore-part necessarily become stronger,
while those of the back, being deprived of their natural stimulus to
action, in consequence of the rod superseding their office, become
diminished in power. Even were there no change in the degree of
strength in the muscles on the fore-part, the head would naturally
fall, if the support afforded by the chin strap were removed; but as
these muscles are increased in power, while those of the back are
diminished, the head must not only fall, but even be pulled down.
However, although the collars and the lead weight, as they are
generally used, are not only inefficacious; but even hurtful,
they may occasionally be useful in keeping the head in a certain
position, after it has been brought to it by such exercises as tend
to strengthen those muscles of the back which support the shoulders
and head. But the opinions commonly entertained, as to the means of
counteracting an habitual stoop, are so erroneous, that even the
position of a tailor sitting on his shopboard is better than the
plans generally recommended. This at first appears ridiculous; but
the manner a tailor holds his body when he walks, proves that there
is something in his habits which tends to the correction of a stoop;
for he is quite a caricature of a strutting erect figure, especially
in the way he bends in his loins and carries his head.
The peculiarity of the tailor’s gait proceeds, in a certain degree,
from the bent position in which he sits: but this explanation is not
at first satisfactory, since it may be observed that other tradesmen,
who also stoop while at work, generally have their head inclined
forwards, and have also a distinct and habitual bend in the neck;
such, especially, is the condition of persons who sit at a table and
stoop forwards, as watchmakers, engravers, &c. It is not difficult
to explain the cause of the difference, and the inquiry will assist
in directing us to the principles which we ought to recollect in our
operations upon the spine.
In the sitting position of the tailor, the head hangs so low, and
so complete an arch is formed between it and the pelvis, that the
muscles of the spine are called into strong action to support the
head; the necessary consequence of this is, that these muscles become
even unnaturally strong, or at least so strong as to predominate
over those by which the spine is [p242] pulled forward. But the
bent position is not the only cause of increase in the strength of
the muscles, for it depends also on the exercise given by frequently
jerking the head backwards. In those who stoop from the middle of
the body, as in writing or working at a table, the muscles of the
spine are not called into action; for, while the head is in this
position, it rests or is supported by the ligament of the neck.
The ligament, being thus kept constantly on the stretch, becomes
lengthened, instead of being made more contractile, as muscles would
be; and hence the stoop is increased. When this is combined with the
consequences of the want of muscular action, the deeper ligaments,
which bind the upper vertebræ, gradually yield; if the operation of
these causes continues for a certain time, the bones and cartilages
themselves become altered in shape, and consequently an almost
irremediable stoop is produced[39].
This view derives confirmation, from what may be observed in the
shape of the tailors in some parts of Germany, who, instead of having
the erect figures of London tailors, are quite bent. On inquiring
into the cause, we find that, instead of sitting as tailors do in
this country, a hole is cut in the table, and a seat is placed within
it; so that their position, while working, becomes nearly the same as
that of persons who stoop while sitting at a table.
It may, perhaps, be objected, that labourers, and especially the
vine-dressers in France, are remarkable for the complete arch which
their body forms, although they bend while at work as much as the
tailor does. This may also be explained; for in the labourer the bend
is produced by the pelvis rolling on the head of the thigh bones,
while in a person sitting as a tailor the pelvis continues nearly
fixed, and the bend is in the vertebræ on the pelvis.
The erect figure of the Turk perhaps comes from the manner of sitting
which is common among Eastern nations; but the heavy turban, and the
spice box slung from the back of the neck, may account in a great
measure for the fine figures of the Turkish Jews who frequent the
streets of London. [p243]
We may even take the shoemaker as an example of the effect of a
particular manner of sitting, and of frequently using the muscles
of the shoulders. He is also a little in caricature, but he carries
himself better than the tailor, and the cause is obvious. The
tailor’s figure is very erect, but the right shoulder is generally
a little higher or larger than the left, from the constant exercise
given to the right arm, while the left rests upon the knee: this
inequality of the shoulders is not observed in the shoemaker, because
he not only uses both arms equally, but the muscles by which the
scapulæ are supported, become so strong by the habit of jerking back
his elbows while he works, that his shoulders always appear more
braced back than those of any other class of persons: indeed, so
characteristic are the figures of tailors and shoemakers, that they
may be easily distinguished in a crowd.
These circumstances are mentioned, as they afford familiar examples
of the principles on which we ought to proceed, in endeavouring
to correct deformities; but it would be ridiculous to propose the
position either of the tailor or of the shoemaker, as the best
adapted to correct a stoop or falling forward of the shoulders.
The preceding observations apply also to the contrivances usually
employed to keep the shoulders back, and particularly to the question
of the propriety of using the common back-collar. The effect which
this instrument produces in ordinary cases may be easily comprehended
by the following diagram.
[Illustration]
[p244]
The part of the back formed by the ribs is not a flat, but rather a
round surface; and as the shoulder-blades rest on this, they would
fall forwards were they not prevented by the collar-bones; but as
these bones are united to the breast-bone by a moveable joint, and
as the weight of the arms operates principally on the anterior
angles of the scapulæ, both the collar-bones and the shoulders would
fall forwards, were it not for the action of several strong muscles
which pass from the spine to the scapulæ. But these muscles may be
destroyed by any contrivance which supersedes their use. For example,
let A A be the shoulder-blades, and B B the muscles which support
them. If the scapulæ be brought close to the spine by the straps
of the collar, and kept constantly so, there can be no use for the
muscles B B. They must consequently waste and become nearly useless,
while those on the fore-part of the chest, being excited to resist
the straps, will become increased in power; and hence, when the
collar is taken off, not only will the shoulders fall forward as in a
delicate person, but the muscles on the fore-part of the chest will
predominate over those by which the scapulæ should be held back, and
_pull_ the shoulders forwards.
The spine and the ribs are occasionally bent so as to have some
resemblance to the back of a spoon. In such cases, the shoulders
not only appear high and round, but the lower angles of the scapulæ
project in an extraordinary manner, because the upper and anterior
angle is not only unsupported by the ribs, but is dragged forwards
by the clavicles which are carried in the same direction with the
sternum. When this is to a considerable extent, it constitutes
the _contracted chest_ or the _chicken breast_. This, in a slight
degree, is common in London, and especially among young lads; it
may be discovered by the coat having the appearance of being more
worn opposite the lower angle of the scapula than at any other part.
Such a condition of the chest can only be completely remedied by
appropriate exercises; but a collar is here necessary for a time, to
keep the bones in the improved condition into which they are brought
by the exercises.
These arguments will probably appear sufficiently well founded to
prove that a girl, under ordinary circumstances, [p245] cannot hold
her head or shoulders back, unless the muscles by which they are
naturally supported are in a proper condition. Various contrivances
have been proposed to strengthen these muscles. Dumb bells, if
managed in a particular manner, are good; skipping, when the arms are
thrown backwards and over the head, is still better; the exercises,
called Spanish exercises, performed with two long poles, are also
useful, but to each of these there may be objections, as they all
operate more or less on the spine or ribs, which, in case of a bad
stoop, are generally affected.
The following anecdote will, perhaps, set the question of the
propriety of wearing the back collar in a correct point of view. A
surgeon was consulted by a gentleman, who is now one of our first
tragedians, as to the best mode of correcting a stoop which he had
acquired. The surgeon told him that neither stays nor straps would do
him any essential good; and that the only method of succeeding was to
recollect to keep his shoulders braced back by a voluntary effort.
But the tragedian replied, that this he could not do, as his mind was
otherwise occupied. The surgeon then told him that he could give him
no further assistance. Shortly after this conversation, the actor
ordered his tailor to make a coat of the finest kerseymere, so as to
fit him very tightly, when his shoulders were thrown back. Whenever
his shoulders fell forward he was reminded by a pinch under the arms,
that his coat cost him six guineas, and that it was made of very
fragile materials; being thus forced, for the sake of his fine coat,
to keep his shoulders back, he soon cured himself of the stoop. The
surgeon was much obliged to him for the hint, and afterwards, when
consulted whether young ladies should wear shoulder straps, permitted
them, on condition that they were made of fine muslin, or valuable
silk, for tearing which there should be a forfeit.
An inquiry into the manner a girl should sit may appear trifling
to those who have not been in the habit of seeing many cases of
distortion of the spine, but it is intimately connected with the
present subject, and is really of considerable importance. The
question has been disputed; one party insisting that girls should
always sit erect, while others are advocates for a lounging position.
It is not difficult to show that both are [p246] wrong;—when a
delicately formed girl is supposed to be sitting erect, she is
generally sitting crooked: to a superficial observer she may appear
quite straight; but any one who will sit on a music stool, and
endeavour to keep his body in a perpendicular line for ten minutes,
will be convinced that it is difficult for even a strong man to sit
as long as a delicate girl is expected to do, without allowing the
spine to sink to one side or to fall forwards.
The attempt to sit erect beyond a certain time is injurious, for
although bending the spine occasionally is useful rather than
hurtful, yet when it is done involuntarily, and when the bend is
attempted to be concealed by an endeavour to keep the head straight,
there is danger of the spine becoming twisted. Indeed, a double curve
is generally the consequence; there is first a bend to one side, to
give ease to the fatigued muscles; and then, to conceal this, there
is a second curve that is necessarily accompanied by a slight twist
in the vertical line of the whole column.
The proposal to allow children to sit in a crooked or lounging
position seems to have been founded on the idea that all the muscles
are more relaxed in this way than even when the child lies at full
length on its back. This notion is certainly incorrect, and such a
mode of sitting is injurious; for even were the muscles more relaxed
by it, the bones and ligaments acquire such a shape as necessarily
produces distortion.
It may naturally be asked how a girl should sit, since it would
appear, that whether she is in an erect or stooping posture, she is
equally in danger of becoming crooked. As sitting, in the manner
generally recommended, affords little or no support to one who is
weak, the safest answer would be, that a delicate girl should not sit
for even more than five or ten minutes without having some support
to her back, and when she is fatigued, that she should lie down or
recline on a couch. But as it would be very annoying to a girl not to
be allowed to sit up except for so short a time, and as a couch is
not always at hand, we must endeavour to show how a delicate girl may
remain in an upright posture, for a reasonable time without incurring
any risk of becoming crooked. This leads to an inquiry into the
merits of the chairs which are at present generally used by children.
[p247]
Young ladies are often obliged, while at their music lessons, to
sit upon those chairs, which have high backs, long legs, and small
seats. These chairs are said to have been invented by a very eminent
surgeon, and are intended, either to prevent distortion, by some
supposed operation on the spine, or as the most effectual means of
supporting the body. It is difficult to imagine how a chair of this
description can effect the first purpose; and to discover how far it
is calculated for the second, the reader should make the experiment
on a chair of the same proportion to his figure, as the chair in
question is to that of a little girl. He will find that if the seat
or surface on which he rests is small in proportion to his body, the
chest will, after a time, either fall forward or to one side, unless
he exert himself to a degree that is very fatiguing. Indeed, if the
seat be at the same time so high, that the feet do not rest fairly
on the ground, but dangle under the chair, a forward position of the
head is almost necessary to preserve the balance of the figure[40].
The objections to such chairs have been met with the assertion, that
girls feel remarkably comfortable in them. This is no argument in
favour of their use, for it is not uncommon for a girl who has seven
or eight pounds of iron strapped upon her body and next to her skin,
to say the machine annoys her so little, that she does not care how
long she wears it.
But whether this chair is agreeable or not, it is easy to show that
it is not calculated to give much proper support to the body, and
that it is almost impossible for a delicate girl to sit long in a
natural or easy position upon it.
It may be allowed, that the chair which we consider the most
comfortable, that is, the chair which affords the most support to
the body, should, if made in proper proportions, be the best for a
delicate girl. In such a chair, the _seat_ should be scarcely higher
than the knees (thus permitting the whole of the foot to rest on
the floor), and of such a size, that on sitting back, the upper
part of the calves nearly touch it. This form of _seat_ is very
different from that of the chair alluded to, the _back_ of which is
also equally objectionable, for, instead of being in [p248] some
degree shaped to the natural curves of the spine, it is made nearly
straight, and projects so as to push the head forwards. A delicate
girl should always sit so as to rest against the back of the chair,
and, if the lower part of her spine is weak, a small cushion will
afford great relief. As it is quite a mistake to suppose that the
shoulders, if raised in any other way than by the action of the
muscles, or by the curvature of the spine and ribs, will continue
high, there is no real objection to a girl who is delicate being
supported by an arm-chair; for, by occasionally resting on the
elbows, a considerable weight is taken off from that part of the
spine which is the most likely to yield.
These observations refer only to the manner in which delicate girls,
whose spines are still straight, should sit: when the spine is
actually distorted, it will be necessary to use other means.
FOOTNOTES:
[37] For this, and some other communications upon the same
subject, we are chiefly indebted to our much-lamented friend and
correspondent, the late Mr. Shaw, Surgeon to the Middlesex Hospital.
[38] When the Russians wish to give a horse high action in trotting,
they accustom him, while young, to wear heavy shoes on the fore
feet. The resistance to be overcome necessarily increases the
strength of certain muscles; and hence, when shoes of the common
size are put on, the horse lifts his feet higher than one which has
not been subjected to this discipline. Some opera dancers practise
with lead weights on.
[39] Elderly persons may recollect how often the girls who worked
at _tambouring_ were crooked: the present fashionable amusement of
embroidering seems to have, in some instances, the same effect.
[40] It must be almost unnecessary to remind the reader, that if the
knees are bent in standing or walking, there is a curve in the spine
at the same time.
_A Critique on the Aplanatic Object-Glasses, for diverging Rays, of_
Vincent Chevalier, ainé et fils. _By_ C. R. Goring, M.D.
The curiosity of many will doubtless be excited, as to what our
neighbours, the French, ever foremost in the pursuit of glory,
both in arts and arms, have been doing in the affair of achromatic
object-glasses for microscopes. With the highest satisfaction I find
myself enabled to state, that Messieurs Chevalier, (ainé et fils,)
No. 69, Quai de l’Horloge, Paris, have rivalled our own artists, in
this branch of the manufacture of optical instruments.
Mr. J. Lister, actuated by a most laudable zeal for the prosecution
and advancement of optical science, as it concerns microscopes,
caused me to order for him one of Messrs. Chevalier’s instruments,
_in Mr. W. Tulley’s name_; for, as Mr. L. wished that Messrs. C.’s
pretensions should be fairly and thoroughly scrutinized, it was but
fair that the latter gentlemen should be stimulated to do their
utmost, by a consideration of the science of their customer. A
critical examination of the object-glasses of this instrument (for
making which every facility was afforded me by Mr. L.), forms the
subject of the present paper. [p249]
I here, then, enter upon the discussion of the merits and demerits
of the objectives of the said instrument[41], these being much more
perfected than those of another, of previous make, which I saw in the
possession of Mr. Howship, of Great George-street, Hanover-square,
to whom I received a letter of recommendation from Mr. Spilsbury, of
Ball-Haye. To the signal politeness of these gentlemen, in furthering
my views, I am greatly indebted.
Four object-glasses accompany Messrs. Chevaliers’ instruments (at
least those marked _perfectionnés_,) usually rated at the following
foci: 14 French lines, 10 ditto, 4 and 4: the two latter combine
together at will, and give a focus of two lines.
14.) Focus about 1.42 of an English inch, clear aperture 0.31,
original aperture as reduced by a stop, 0.10.
It is perfectly achromatic with its clear aperture, and may be used
without a stop on most transparent objects; requires to be cut off
to 0.23, to give the necessary distinctness for opaque ones.—(When
I speak of the apertures which C.’s lenses will bear, I must be
understood, here and elsewhere, only with regard to the _middle of
the field of view_, or rather that part of it where the distinctness
is greatest[42], for double object-glasses give the central rays only
correct, and confuse the oblique ones very much, for which reason,
conjoined with the small apertures they admit of, they were abandoned
by Mr. Tulley, for the triple construction, the true and regular form
for the microscope.)—There is an excess of spherical aberration in
convex lenses; neither are the glasses well ground, or centered, or
duly adjusted. The concave of this object-glass is tarnished, and
there are traces of seediness in the cement, which is, indeed, to be
seen more or less in the whole of them.
10.) Focus about 0.91, clear aperture 0.23, original stop 0.09.
[p250]
This object-glass is under corrected in point of colour, and wants
to be made longer in the focus to be achromatic. The excess of
uncorrected spherical aberration is in the convex lens; the glasses
are not well ground, centered, or adjusted; the same appearance of
tarnish as in 14; bears its clear aperture for the middle of the
field on most transparent objects, but must be cut off to 0.2 for
opaque ones.
Both of these object-glasses are ineffective upon test objects, from
want of sufficient power and aperture.
4.) Focus about 0.43, clear aperture 0.23, original stop 0.09,
perfectly achromatic. The uncorrected spherical aberration is in
the concave; centering and grinding very fine, but in very bad
adjustment; shows some transparent test-objects pretty well with its
clear aperture, and, cut off to about 0.16, performs well on many
opaque ones.
2.) Focus about 4.7, clear aperture 0.21, no stop, perfectly
achromatic, surplus of spherical aberration in the concave as
before; centering and grinding very fine; adjustment tolerable; in
other respects very similar to 4. This object-glass being adjusted,
does more singly on test-objects than any other, and carries an
aperture of 0.16 well on opaque bodies, showing the lines on the
diamond-beetle’s scales strong and well cut out.
Combination of 4 and 2—(quadruple.)
I am happy to be able to speak in terms of almost unqualified
approbation of this composition. It, of course, surpasses the
performance of any single triple-glass, _on those test-objects which
require extravagant angles of aperture_. The field also is good all
over; or at least would be, if the glasses were in adjustment, which
is the only drawback upon it. The focus of the combination is only
0.26, yet it performs admirably on transparent test-objects with its
naked aperture of 0.23, and is very fine on opaque ones with 0.16,
and doubtless would carry 0.2, if the adjustment was duly carried
into effect.
Messrs. C. have, I think, most assuredly here hit upon one of the
very best _compositions_ for the object-glass of a microscope; all
the imperfections of double object-glasses, _taken singly_, are here
done away, while their thinness and agglutination into one mass
allows of their combining together almost as if they were simple
plano-convex lenses, leaving moreover abundance of space for the
illumination of opaque bodies. [p251]
I must here state, that Messrs. C.’s object-glasses are all stuck
together, I believe, with fused gum-mastic, or, perhaps, with very
thick mastic varnish. This practice seems, in theory, to be bad, most
especially if the curves united together are not of the same radius;
nevertheless, practically speaking, the process of soldering seems
to me to do more good, by the obliteration of two surfaces, and by
keeping the glasses immovably adjusted, than harm in any other way. I
cannot, in fact, discover any very sensible difference in the optical
performance of these small achromatics, whether stuck together or
not. I _fancy_ that they have a little more light and clearness
when cemented, (as they certainly should have,) but cannot be very
positive. I hold it as a maxim in practical optics, as in our common
law, “de rebus non _apparentibus_ et non existentibus eadem est
ratio.”
I may observe, that Mr. Lister has combined that marked 10, with 4,
and finds the performance proportional to that of 4 and 2.
It will be remarked that Messrs. C., from an apparent ignorance of
the value of aperture; and perhaps impressed with the too common
and prevalent idea, that, having once obtained distinctness and
achromatism in their object-glasses, every thing else might be
accomplished by a condensation of artificial light, have reduced
their apertures to such a degree, as to render their instrument as
ineffective upon test-objects as a common compound; for when the
opening of an aplanatic glass is cut off to the same diameter as a
common one, it shows _nothing more_, though it will certainly exhibit
objects far _more satisfactorily_. Upon the apertures of microscopic
lenses their effects entirely depend, as was remarked a long time
ago by the great Huygens. An achromatic glass is more valuable than
another, merely on account of the larger aperture it will bear,
without causing aberration, and consequent indistinctness. Those who
are in possession of Messrs. C.’s microscopes should get the stop
behind the object-glasses turned out, and procure others to be used
ad libitum, according to what the goodness of the object-glasses will
permit.
I feel myself called upon, however, to state, that, since the
completion of Mr. L.’s microscope, Messrs. C. _have enlarged the_
[p252] _apertures of their object-glasses to the requisite angle_,
and have moreover _arrived at the true method of adjusting them_, so
that they are _now_ free from those objections which applied to Mr.
Lister’s, and are in all respects unexceptionably finished.
I know not if any dispute will ever arise hereafter, as to who is
to be considered as _the original maker of effective aplanatic
object-glasses for microscopes_[43]. It is of very little consequence
in the present instance, for it so happens that Mr. Tulley and
Messrs. Chevalier have been so totally unconnected with each other,
and have worked upon such totally different principles, that it must
be evident, on the most superficial consideration, that both are
entitled to the honour; nevertheless I apprehend it can be proved
that Mr. Tulley made an effective one before the Chevaliers, having
completed his in March 1824. The date affixed by Chevalier to his
first instrument is 1825[44].
[Illustration]
It requires moreover a stretch of complaisance, not to be expected on
this side the Channel, to be enabled to admit that the best double
object-glass is (_taken singly_) effective; or that, in consequence,
Chevalier made an _effective one until he had enlarged his apertures,
and combined two together_[45], which combination is not to be met
with in his primitive instruments. Mr. Lister, (to whom the public
is mainly indebted for the present eclaircissement concerning
Chevalier’s instrument,) has, by a peculiar method of his own
discovery, measured the [p253] curves, thicknesses, and diameter,
&c. of that marked 14, which I here give (unfortunately one of the
least effective of the set,) however, in all probability, the rest
are constructed on the same principle; the annexed drawing by Mr. L.
will sufficiently explain itself. Nothing can surpass the beautiful
simplicity of Chevalier’s, or rather Euler’s, curves, which, it will
be observed, are all alike[46]. The production of _deep_ achromatics
must ever be a task of some difficulty, even to those who thoroughly
understand their humours and punctilios; and unscientific artists
will, I think, be much more likely to succeed on the French plan,
than the English one. Two double object-glasses, by themselves,
are very poor things; but, when combined, perform admirably, and
will, I believe, (if the three curves are of equal radii,) be far
more easily executed than one of the triple Tulleian construction.
The dense flint-glass of Guenard, or Frauenhofer, however, will be
an indispensable requisite, from the nature of the curvatures. A
triple Tulleian object-glass, and a thin double one of Chevalier,
(a composition first conceived and adopted by Mr. Lister,) form an
excellent combination, and give a very vivid light, without softness,
dulness, or nebulosity. This, I think, is the extreme number of
glasses which ought to be tolerated. Let it never be forgotten, that
_a really good triple glass will bear an aperture quite sufficient
for ninety-nine objects out of a hundred_. I myself denounce the
practice of combining glasses together, _in all those cases where
they are capable of doing their work alone_. I shall always consider
it as a clumsy, bungling, and unworkmanlike method of obtaining a
short focus, combined [p254] with a large angle of aperture. If a
man aims at perfection, and wishes to distinguish himself in this
branch of optics, let it be done by working perfect triple glasses of
0.2 and 0.3 inch focus, with 0.1 and 0.15 of perfect aperture, like
those of Mr. W. Tulley and Mr. Dollond, or deeper still, if he is
able; and it is with the most cordial satisfaction that I am enabled
to inform my readers, that Messrs. Chevalier (duly appreciating the
regular triple construction as the true form for the microscope) have
applied themselves diligently to the manufacture of this species
of objective, from which they have already had excellent results.
It is a fundamental principle, that all superfluous refractions
and reflections are to be avoided in the construction of optical
instruments. As a radical reformer of microscopes, I can tolerate
no abuses in them, or show any quarter to their abettors. Messrs.
Chevalier have also undertaken the manufacture of achromatic and
catadioptric microscopes, after the fashion of those made by
Professor Amici, of Modena, which were so much and so justly admired
by the cognoscenti of this country.
It only remains for me to observe, that though two double-cemented
object-glasses form the most perfect _combination_ from the fewness
of their surfaces, and consequent brightness of their image, yet a
fusion between the Tulleian and Eulerian constructions seems to be
the _most convenient_ for general use; by this, of course, I mean
a triple glass with a double one, to apply before it occasionally,
à la Lister. Mr. Dollond and Messrs. C. have demonstrated that two
object-glasses _may be combined with the best effect, which are both
good, and work well separately_; but Mr. Tulley has constructed a
double one, which, useless by itself, when applied over a triple one,
(made to act singly,) corrects that excess of spherical aberration
in the concave lens, (by its own excess in the convex,) which, when
the aperture is large, is the eternal vice of all the best single and
compound object-glasses for diverging rays which I ever saw. This is
perhaps the ultimatum of improvement, though a quadruple one, on the
same plan, might have the advantage in greater light and clearness,
from its simplicity, and the paucity of its surfaces.
The quadruple or quintuple object-glasses are those which [p255] are
best adapted for the solar microscope, for they give a full-sized
field of view to this instrument, good to the edges, which no single
object-glass will do, as I have had occasion to remark in my paper on
Mr. Tulley’s aplanatics, unless converted into a compound, by means
of eye-glasses, &c. This popular and highly amusing instrument will
now receive the utmost reformation and improvement of which it is
capable, and become truly scientific in its construction: hitherto it
has been a mere toy, but one degree removed from a magic lantern.
I shall now allow Messrs. C. to say what they can for themselves, and
to detail the various modifications which they have introduced into
their instruments, since they executed Mr. Lister’s order, by giving
a translation of a letter I have received from them on the subject,
and shall conclude by expressing a hope that no national or illiberal
feeling has entered into the composition of this critique, and that I
have used my oil, vinegar, and pepper in correct proportions.
“_Paris, Oct. 15_.
“Sir,
“Accept our thanks for your extreme complaisance in offering
to publish the results obtained by us in the construction of
microscopes. Since the order executed for Mr. Lister, we have
improved those instruments last completed, by greatly enlarging
the diameter of the illuminating mirror, in order to obtain still
greater light. The prism for opaque bodies is diminished about one
half, and by a small modification in its mounting is rendered more
serviceable: the diminution of the length of the body has enabled us
to augment the magnifying powers by different eye-glasses, and the
four double object-glasses placed in a better mounting can be used
separately or in superposition, according to the pleasure of the
observer, either to form quadruple objectives, or even to combine in
a mass together. This last arrangement produces a great accession
of magnifying power, without injuring the clearness of the image or
arresting much light.
“You see, Sir, that we have the pleasure of coinciding perfectly
in your opinions about improvements, for we adopt the quadruple
object-glass as the best, and we give three changes [p256] of
eye-pieces. The double motion given to the body of a microscope is,
in our idea, the defect of all those hitherto constructed; for, as
the optical part should remain perfectly centred with the mirror
and the diaphragms, it is evident that the least derangement of it
from this position must destroy the perfection of the image: the
stage then only should move[47] without affecting the diaphragms
or the mirror, and in this we [p257] have well succeeded in
the construction of the microscope of Sig. Amici. But all these
arrangements much augment the price, and an observer ever so little
practised will always find the object easily enough by means of his
hands.
“The prices of our achromatic microscopes are as follows:—
“_Achromatic microscope_, like Mr. Lister’s—300 francs.
“The same, with the latest improvements, three eye-pieces, and
camera lucida for drawing the magnified objects—400 francs.
“_Amician Microscope_, one horizontal achromatic, the stage
giving all the motions to the object, with a micrometer screw,
five eye-pieces, two camera lucidas, hand magnifier, frog trough,
accessary apparatus, &c. _One catadioptric microscope_, mounted on
the same stand, and adapting itself to the same apparatus; the two
instruments inclosed in a mahogany case—1000 francs.
“We trust that the very moderate prices of these instruments,
together with the care which we bestow on their construction,
will procure us orders for them. Their superiority has been duly
recognized by the jury of the Exhibition of the Products of
Industry, which has been pleased to decree to us a silver medal.
“The Amician achromatic microscope is composed of a tube seven
inches long, at the extremity of which is placed a prism, which
reflects at a right angle the rays which come from the object-glass,
composed (_as in our microscopes executed since 1824_) of four
double object-glasses, which may be used separately, or two, three,
or four at a time. The stand is a square bar, which has a rackwork,
carrying a moveable stage, which, by means of adjusting screws
ingeniously disposed, permits an object to traverse the field
of view in every direction. This disposition gives the power of
determining the real dimensions of objects submitted to observation
by means of the micrometer screw, which is placed at the side, while
the camera lucida affords the means of drawing their outline, and
consequently of measuring the magnifying power.
“The rays proceeding from the object which have passed the
object-glass, and have been rendered horizontal by the prism, are
received by different eye-pieces disposed after the manner of [p258]
Ramsden. Their power can be varied. Each instrument carries six,
five of which can be attached at pleasure either to the catadioptric
or the achromatic. The deepest belonging to the reflector is a
single lens of half a French line focus, and the most powerful of
the achromatic is a line and a half.
“Such, we think, are the details which you required: we wish that
they may prove agreeable to you.
“We beg you to accept the assurance of the high consideration with
which we are, Sir,
“Your very devoted Servants,
“VINCENT CHEVALIER, ainé et fils.”
“69, _Quai de l’Horloge_.”
FOOTNOTES:
[41] The objects employed by me in looking into the defects and
excellencies of these glasses, were an artificial star, and a piece
of enamelled dial-plate, the phenomena presented by which, _when put
out of focus_, incontestably warrant the judgment I have pronounced
upon them, as any, true optician will admit.
[42] When an object-glass is out of adjustment, its maximum of
distinctness is not in the centre of the field of view, but
somewhere else, according to circumstances.
[43] The question must naturally resolve itself into this point,
for achromatics for microscopes, (as they are called,) were made by
Dollond, Martin, and Pollard, many years ago; the only objection to
them was, that they were _not effective_, consequently, _nominal
only_, and useless. I defy any man to produce an _effective_
object-glass, which can satisfactorily be proved to have been made
before 1824.
[44] See the _first_ instruction published by Messrs. C. along with
their microscopes: “Microscope Achromatique selon Euler,” &c. I
apprehend there is a misdate in Messrs. C.’s letter at the end of
this paper, where they state they have made the achromatics _since_
1824, _with four objectives_, which implies that they also made them
before that period, but in another way.
[45] Mr. C. Tulley recommended the combination of two achromatics
together from nearly the beginning of his son W.’s labours upon
them, who rejected the idea, together with myself, as giving rise
to too great a complication, _always supposing that triple glasses
must be used_. I myself combined two triple achromatics together,
for experiment sake, in a very early stage of our proceedings, but
liked not the result, though effects were certainly produced by the
composition, which could not be obtained from the best individual
triple one.
[46] The theory on which these object-glasses are constructed is
contained in a paper of Euler’s, published at St. Petersburgh, in
1774. Messrs. Chevalier have caused it to be inserted entire in the
“Bulletin de la Société d’Encouragement de Paris,” No. CCLIV., for
Aug. 1825.
[47] [Illustration]
This is the theoretical view of the case, the practical one is
different, as frequently happens. _Opaque objects_ are not affected
at all by the eccentricity of the axis of the body: nor can I
recollect that I ever felt any particular inconvenience from the
motion of the optical part, even with transparent subjects, unless
it was thrown _very much indeed_ out of the axis of the illuminating
mirror. On the other hand, it is notorious that _living_ aquatic
insects and animalcules are the most _popular_ and _entertaining_
objects which microscopes can show. These are, for the most part,
abundantly restless; and if the stage on which they are placed has
any motion, their natural unquietness is so much exasperated, that
it becomes almost impossible to get a good observation of them
at all. I once set to work at making some drawings of a variety
of new and original objects of this class (which, I trust, will
one day be published) with a microscope having all the requisite
motions applied to its stage, and am confident that I had thrice
the labour fairly appropriate to the execution of my task from this
oversight. The very tremor produced by the transition of a carriage
in the street, is frequently sufficient to unsettle live objects
when disposed to be still and quiet, and put them in a fidget for
a quarter of an hour. It is very unfortunate that the mountings
of optical instruments are made in general by mere mechanics, who
seldom or never observe with them, and consequently know not the
exigencies which occur in practice. It is still more unfortunate,
that in the science of fitting up microscopes, an ounce of a man’s
own wit is worth about a ton of his neighbour’s. Was it not that
I dislike to verify this adage myself, I should recommend the
following motion to be applied _to the body_:—let the socket of
the arm which carries it have a smooth rotatory motion on the head
of the bar in the usual way, conjoined with another horizontal one
produced by rackwork attached to the said socket. Let the pinion
which belongs to the latter movement be made very strong, so that a
lever about three inches long may project from its centre: this is
to be held in the hand, the thumb and index finger operating on the
rackwork, while the two little fingers give a rotatory motion by
working the lever end. _This rapid double motion is here completely
under the command of_ one hand, _while the other is at liberty to
adjust the focus_. I know of nothing better for general purposes, or
in particular for following the motions of live insects, &c.; but
when _only inanimate ones_ are to be the subject of microscopical
study, I prefer the motion of the stage, for the reasons stated by
Mons. C.
_On the Existence of Chlorine in the Native Black Oxide of
Manganese._ By John M’Mullen, Esq.
In the paper relating to this subject, which the editors of the
Quarterly Journal of Science obligingly inserted in the forty-fourth
number of that work, I described some experiments which I had made,
to show that chlorine is uniformly evolved from the Native Black
Oxide of Manganese by the action of sulphuric acid, under certain
circumstances, which I endeavoured to detail with strict accuracy, so
as to prevent any mistake or failure in the event of the experiment
being repeated.
Upon this paper Mr. Richard Phillips has made some observations
in the Philosophical Magazine and Annals of Philosophy for April
last, to which I am desirous of briefly adverting. He says, “Mr.
M’Mullen having observed, when sulphuric acid is added to peroxide
of manganese, that chlorine is evolved, he conceived it might be
derived from an admixture of muriate of manganese, iron, or copper;
but having washed some of the peroxide of manganese with water, he
did not find that any chloride of silver was precipitable from it;
he, therefore, concluded that the peroxide in question contained no
muriatic salt.” If Mr. Phillips will take the trouble to refer to my
paper, he will find that this is by no means the statement which it
contains. I observed that, in order to separate any soluble [p259]
muriates which the oxide used might, in the first instance, have
contained, “I washed it every day, for three weeks successively,
using sometimes hot and sometimes cold water: _at the end of that
time_, I tested the water, which was _then_ decanted from the
washed manganese, by the nitrate of silver, but without finding the
slightest appearance of precipitated chloride. I then poured upon the
manganese four times its weight of dilute sulphuric acid; allowed the
mixture to stand _for about four weeks_, occasionally agitating it,
and at the end of that time, found, when the dilute acid, now of a
deep crimson colour, _was removed from the subsident manganese_, and
the latter agitated, that the most decisive evidence of the presence
of chlorine was exhibited in the vapour evolved from it.” I stated
further, that I had “carefully preserved this particular mixture,
and that after a lapse of more than twelve months, the residuary
manganese, when the supernatant acid was removed, continued to evolve
chlorine.”
In this experiment my object was effectually to purify the manganese
used from any soluble muriate which might by possibility have been
mixed with it: I did not, however, test the water _first_ used in
washing it, but merely that which was _last_ removed from it.
Mr. Phillips proceeds to observe that he had prepared some
observations, and at considerable length, _to prove_ that the author
of the above paper has been completely misled by “forced analogies”
and “erroneous experiments;” but that it _afterwards_ occurred to
him, that it would be better to show, in a few words, the real source
of the chlorine in question, the evolution of which from peroxide of
manganese _he had noticed some time previous to the publication of
my papers_. That with this view he had procured various specimens of
the peroxide of manganese, (one of them in the crystallized state,)
which were reduced to powder, and on the addition of sulphuric
acid, chlorine was evolved from each. That he then washed separate
portions of them with distilled water, and on the addition of nitrate
of silver to the washings, chloride of silver was immediately
precipitated: sulphuric acid being poured upon the washed peroxide,
no chlorine whatever was evolved. That he further added sulphuric
acid to an unwashed portion, and to one which had [p260] been
washed, and referred both to a _bystander_, who immediately detected
the odour of chlorine in the former, but not in the latter. He then
proceeds to show that the specimens of manganese which he had made
the subject of this experiment contained a portion of lime, and
he infers that the black oxide of manganese consequently contains
muriate of lime.
Mr. Phillips asserts that I have been misled by erroneous
experiments. My reply is, that the experiment to which he refers,
and which I have recapitulated, was carefully made, and is truly
and faithfully detailed. In what, then, is it erroneous? It is not
incompatible with that which he has produced as a refutation of it,
inasmuch as he did not wait the result for which the perusal of my
statement should have prepared him, and which he clearly should not
have anticipated. He states that chlorine was not evolved from washed
manganese at the instant when sulphuric acid was affused upon it.
This is not a contradiction of my statement: I affirmed that, after
washed manganese had been exposed to the action of sulphuric acid
for a very considerable period, I distinctly observed the evolution
of chlorine, and that for twelve months afterwards, _under the
circumstances detailed_, this continued to be the case:—all this
I deliberately re-assert. I have frequently met with specimens of
manganese which, upon the first affusion of sulphuric acid, gave off
chlorine; but _in general_, as far as my experience goes, _this is
not the case_: were it of uniform occurrence, and that the mixture of
sulphuric acid and oxide of manganese rendered chlorine evident to
the smell, the fact _could not have remained unnoticed till now_.
The observations of Mr. Phillips, to which I now refer, did not come
into my hands till about three weeks ago. It fortunately happened
that I had still preserved the specimen of washed manganese upon
which sulphuric acid had been affused, under the circumstances
already recapitulated, and it occurred to me that this would afford
occasion, as decisive as I could desire, to put the accuracy of my
original experiment, and the conclusions drawn from it, to further
proof. I am bound to premise that this specimen of manganese,
after having been in the first washed and subjected to the action
of sulphuric acid, as already mentioned, has ever since remained
in [p261] the vessel in which the experiment was at first made,
covered with dilute sulphuric acid,—a period of more than eighteen
months; and it will scarcely be doubted that, in the course of that
long interval, any muriate of lime which it might have originally
contained must have been thoroughly decomposed. Upon removing the
supernatant acid, the residuary manganese gave sensible evidence of
the presence of chlorine; paper stained with the solution of indigo
in sulphuric acid was readily bleached by it, &c. I now proceeded
to wash the manganese in pure water, and continued to do so until
the acid was no longer perceptible to the taste. I then washed it
three times successively with distilled water, and after decanting
off the fluid of the last washing as closely as possible, added pure
sulphuric acid in considerable quantity, and stirred the mixture
thoroughly, after it had cooled, with a glass rod. At this time
no vapour of chlorine was evident either to the smell or to the
usual tests. The mixture was then set aside, and allowed to stand
undisturbed for ten days: at the end of that time, when the acid
was poured off, and the subsident manganese agitated, the vapour of
chlorine was as distinctly manifest as when it was first subjected to
experiment more than a year and a half ago.
_Dublin, June_ 11, 1827.
_Modern Improvements of Horticulture_.
That gardening has always been one of the most natural, as well as
the most useful occupations of mankind, is obvious: that it has
advanced—been retarded—or flourished, according as general taste
or wants, or peculiar political, moral, or local circumstances,
were favourable or adverse, is also sufficiently evident from all
historical testimony;—but in no age has it advanced with such
rapid strides towards perfection as it has done within the last
fifty years. To bring the modern improvements in array before the
reader,—to estimate their advantages in a public and private point
of view,—to look forward from our present elevated station to the
probable results of continued, and extended application,—may be an
amusing, if not an [p262] useful inquiry: it may tend to remove
barriers which are only imaginary, and by freeing the thinking powers
of practitioners from the trammels of custom, lead them forward
into that expanse of operative freedom, where much remains for the
exercise of the inquiring mind, and experimental hand, in exploring
the yet untrodden field of practicability, and calling forth the
still latent powers and susceptibilities of pregnant nature.
When we turn to the history of the first ages, we hear of a garden as
soon as we hear of man; and though, from the paucity of description,
we can only form ideas of such a place from the effusions of the
poet, rather than from the detail of the historian, yet, in judging
from what still appears of aboriginal scenery, we may conclude with
Milton that a garden was a place,
“A happy rural seat of various views;
Groves whose rich trees wept odorous gums and balm;
Others whose fruit, burnished with golden rind,
Hung amiable, and of delicious taste:
Betwixt them lawns—or the flow’ry lap
Of some irriguous valley spread her store.”—_Par. Lost_.
If such a place, it required care to rear the tender—to check the
luxuriant—correct the irregular—to support the burdened—extirpate
the noisome weed—and repulse the browsing animal. Such was the only
occupation of the first gardeners: for in those highly-favoured
spots, those natural paradises, (some of which still remain in
India,) where the groves which formed the habitations also supplied
the simple food of the inhabitants; where the cocoa-nut[48], with
its various liquors, abounded; [p263] where the date, the mango,
tamarind, and lime dropped in profusion into the hand; where the
melon tribe upon, and the nutritious yam beneath the surface of the
bountiful soil, were all spontaneously supplied without care, and
without toil:—in such circumstances, neither sagacity to contrive,
nor ability to perform, were necessary, further than collecting and
preserving those spontaneous gifts of nature.
But population increased; and when mankind became translocated to
regions less favourable to vegetation, and where the spontaneous
productions of the earth were insufficient for their subsistence,
then the business of the planter and cultivator became a necessary
occupation; and hence gardening would begin to assume a systematic
form.
As improvements, and the times in which they took place, have
descended together in continuous and collateral streams, the
narration may be divided into three periods, viz.:—From the earliest
ages to the beginning of the sixteenth century;—from the beginning of
the sixteenth century to the end of the seventeenth;—and from that
period to the present time.
We have already hinted at what were probably natural, or aboriginal
gardens: the account is so far feasible from the fact, that such
places and productions may be met with on the peninsula of India,
at the present day: true it is, they cultivate rice, and some few
inferior plants, where they have opportunity, and use them along with
their wild fruits; but when they cannot procure these cultivated
necessaries, (which sometimes happens,) they must rely on the natural
productions. It is necessary to add, that some of the castes, from
religious principle, abhor the use of almost any kind of animal food;
and, therefore, vegetables are their sole support.
From Egyptian and Jewish history, we learn that gardens [p264]
were an appendage of the palaces of their princes, and other great
men, for personal solace and gratification; but how far the art was
systematized, either in knowledge or practice, history is silent.
Throughout the Assyrian, Babylonian, Persian, and Macedonian empires,
we learn but little more than that ornamental gardening was carried
to an extravagant height in their artificial formation; insomuch
that one of the Babylonian princes built what were called “hanging
gardens,” that is, a vast and lofty pyramidal structure on arches,
arcades with terraces surmounted by other arcades, and carried up in
gradations to a great height. The terraces being planted with the
choicest trees, presented to the distant spectator a verdant hill
of foliage in the midst of a large city, and lifted the sovereign
proprietor far above the noise and intrusive notice of his vassals
below; at the same time, yielding him all the sweets, seclusion, and
quiet of the country, even in the purlieu of his palace! The idea
of such an ornamented and elevated structure for a mighty sovereign
was certainly sublime, and far surpassing all that has been yet done
(though it has been suggested by Mr. Loudon) in the western world;
and though only a monument of wealth and personal pride, prompted by
conjugal regard, and entirely artificial, was certainly proper for
the place where it stood, worthy of the prince who erected, and the
extensive empire to which it belonged.
Throughout a long-following period, and up to the time of the Romans,
we learn nothing particular respecting gardens, only, that among the
Jews, they had gardens for herbs, vineyards, and even gardens for
cucumbers: but as frequent allusions are made to them, it is probable
that gardening had then become a distinct calling, as we find it was
among the Romans, as soon as their extensive conquests were secured.
As the arts and arms of the Romans went together, no doubt a very
wide circulation of all that was known of gardening in Italy, was
transferred thence. Their writers on rural affairs preferred _agri_
to _horti_culture; but their sound knowledge of the former shews
no inconsiderable share of acquaintance with the principles of
the latter; and as their practice, as well as the seeds of their
products, would be introduced wherever the climate permitted, it
is more than probable they [p265] laid the foundation of British
gardening. The rules and examples left by them, were probably
continued, with occasional accessions to the stock both of practice
and production, throughout the Heptarchy, the domination of the
Saxons, Danes, and Normans: but these troublous times were not
favourable to the prosecution of the arts of peace; and it is not
likely much advancement in the art took place until the Norman power
was fully established; and even then their castellated mansions
precluded any extensive adaptation of garden, from the necessity of
forming the glacis, for the greater security of the baronial hall:
and though it is probable that, at this time, not a dwelling, from
the regal palace to the cottage, but had a garden of some size or
other, yet the best practice was confined to the monasteries, and
other religious corporations of those days, all over Christendom.
Their education and leisure, their foreign intercourse, their
interest in the tithes, and their love of superior vegetables and
condiments, on the many days they were restricted from indulging
in the consumption of animal food, all contributed to incline the
monks to prosecute gardening on the most approved plans. Thus,
Italy, Spain, and Germany became famous for their superior culinary
vegetables, as France was for improved fruits; indeed, when war
depopulated or devastated a country, and when the gardens of the
château became a sacrifice to offensive or defensive operations,
and when the potageries of the hamlets were trodden under foot and
destroyed by a licentious soldiery, the gardens of the religious
houses were often spared, and, consequently, many roots and fruits
found there an asylum, which was denied them in less privileged
places.
In looking over the lists of plants cultivated in those days, we find
the names of a great majority of the common sorts now in use, as
well culinary, as for the table or the press, with a great addition
of physical plants, it being then a prevalent supposition that
remedies for all the ailments of the human frame were existent in
the vegetable kingdom, if they could be detected; the cultivation
and gathering of simples, therefore, was a business which employed
many heads and many hands: even the Corinthian pillars of the noble
profession of physic were not entirely free from that malaria, which
was generated in the fumes of the herbalist’s shop! [p266]
Ornamental gardening had hardly showed its graceful head; the little
that had been done of this in England, was only in imitation of the
Italian school, though without their accompaniments of splendid
architecture, classical sculpture, and costly fountains. Such a
style, in the near neighbourhood of a palace or mansion, is imposing
and suitable, but the outskirts of such gardens, which should have
been gradually blended with and into the free and beautiful forms
of nature, were bounded and deformed by tortuous labyrinths, by
complicated folds of nicely-clipped hedges, involving each other for
no purpose than affording seclusion from the “licentious eye,” or a
“maze to the intruding foot.”
It may be observed as somewhat unaccountable, the excellent taste of
their landscape painters was never transferred from the canvass to
their style of ornamental gardening. But so it was: the people who
had all kinds of assistance from artists of the first order, and from
classical and picturesque association within their own territory,
long remained blind to what was so natural and so manifestly within
their reach!
In useful and profitable gardening, the fine climate of Italy gave
great facility for successful cultivation of a profusion of the
finest fruits, and being an advanced post for the reception of all
valuable plants from both Asia and Africa, it much sooner than other
European countries possessed culinary vegetables in great variety,
and of salad-herbs a numerous list.
From the commencement of the sixteenth century the improvements
in gardening began to take the form of a system. The increasing
splendour of the English court, during the reigns of the virgin
queen and her father, and the princely establishments of some of
her courtiers, called the art of gardening into notice and repute,
and gave an impulse to the yet dormant powers of horticultural
practicability. Continental artists were generally employed in
laying out the greater works. The sum of their professional ability
was chiefly geometrical, an exact knowledge of straight lines,
squares, and curves; they could line out a polygonal basin to a
hair’s breadth, and construct a many-tiered jet d’eau in the midst.
Such, however, were the principal features admitted into, and which
constituted the style of those days, and continued through that and
the succeeding [p267] century. In the latter (the seventeenth),
and during the domestic broils which then convulsed the kingdoms,
gardening appears to have been, as to style, almost stationary. In
the mean time, however, the Reformation had been silently working
salutary effects, not only in the deliverance of men from a servile
religious thraldom, but also from the dogmas of precedential custom,
and by imbuing them with a spirit of independence with respect to
others, gave, what was better, a _self-dependence_ in exertion,
whether of mind or action; and, after a few years of revolutionary
excess, and abuse of this inestimable acquisition of mental freedom,
at last, in 1688, settled down into that rational state of composure,
which, with few interruptions, has happily remained to the present
day.
Then it was that gardening, in all its branches, was patronised and
encouraged. Tournefort in France, and Ray in England, enlightened
the public by their description, enumeration, and classification
of plants. Evelyn called attention to the usefulness and national
value of forest trees; several authors developed the mysteries of
kitchen-garden and orchard management; collections of exotic plants
were made, and glass-cases built for their reception; floriculture
received a share of the gardener’s attention; and in short, there
seemed to be, about this time, a general movement by united exertion
to gain what had been previously neglected, and complete what had
been only feebly attempted.
The accession of William and Mary to the British throne very
naturally introduced Dutch gardening and architecture. The old
Italian and French styles received very little, if any, amendment.
The avenue, the canal, the rectangular clumps and borders, the
shelves and slopes, the terrace, with its stairs, were all maintained
and extended, the whole surrounded by exactly-clipped hedges, and
bedotted with fanciful and unnaturally cut trees. This expensive and
ridiculous fashion had its admirers for a time, but at last fell into
disrepute, not by a bull or anathema, but chiefly by the keen sarcasm
of a Pope!
Kitchen-gardens were improved by additional brick-walls for the
more delicate kinds of fruit, as vines, figs, peaches, nectarins,
apricots, &c. Hot-beds were in general use, and, many hot-houses were
erected for different kinds of the above [p268] as well as for the
pine-apple. In those days our fruit-lists contained twenty sorts, of
which there were many varieties. Of culinary vegetables there were,
of roots eighteen, of shoots four, of leaves fourteen, of flowers
three, of seeds three, of pods two, and of herbs for all purposes
twenty-five.
From that period, the commencement of the eighteenth century, every
succeeding year brought forth new objects of the gardener’s care, and
improved operations for his imitation. The acquirements of natural
science, radiating from such a character as Sir Hans Sloane, whose
theories were imbibed and confirmed by the practical abilities of
Philip Miller, were, at that time, like the orb of day bursting
from behind a cloud! Scientific light and practical life were shed
on all around, and the foundation was then laid, by their united
means, on which has been raised almost all the varied structure
of modern horticultural improvement. It would be impossible, as
needless, to give the names of the authors, who, from this period,
showed themselves in print on the subject of gardening, for, were
the respective merits of their literary labours noticed, and the
successive discoveries and advances chronicled, the amount would
be voluminous indeed. But the following celebrated names cannot,
in justice to their memories, be omitted. The great Linnæus was
deservedly at the head of the botanical branch of gardening;
Miller, with his satellites, Gordon, Lee, and Aiton were at that of
practical botany, as well as of all the other parts of operative
gardening; and, as a leading orchardist, Kennedy, and many others
on miscellaneous subjects, produced respectable directories and
kalendars.
The improvement of ornamental gardening kept pace with that of
the more useful. Soon as the old style of rigid formality had
been exposed, it was exploded; more refined principles of taste
prevailed; its outlines became better defined; it was found that
there are certain fixed principles in nature, on which the elements
of true taste are naturally (not capriciously) founded; that delight
and gratification to the eye, or mind, can only arise from the
harmony and fitness of the combinations of art or design; that the
sensations of beauty and sublimity can only be conveyed by congruous
associations of parts to the whole; and that the incidents found in
[p269] conjunction in nature, should be the objects of imitation
of the gardener’s, as they had long been that of the painter’s art,
with this exception, that in the immediate vicinity of the mansion as
much of the old style should be retained as will harmonize with the
necessary artificial façade of the architecture; but soon as departed
from these creations of art, let then appear the varied flow of
nature’s devious garb.
The art of painting had, in the best schools, proceeded on such
principles, and the formation of real scenery was improved from
what was so prominent in the fictitious. Some painters, even Claude
Lorraine himself, have occasionally erred, from what may be called
_exuberance of design_, in producing extreme effect, by introducing
lights which never can be seen by day or night, at dawn or twilight;
by trees which never existed, and by forms[49] which had only an
imaginary existence. Landscape gardeners, too, in the transition from
the tame to the more natural style, have run into error, by imitating
admirable incidents frequently seen in nature’s works, forgetting
that their value springs entirely from their having happened by
chance, but, as works of art, lose all their interest, and become
insignificant.
We are now arrived on the confines of our own times, of which we will
take a general view, and which will sufficiently show the accumulated
assemblage of horticultural objects, productions, and knowledge; and
which will also give, what was proposed, a comparative survey of the
extent of our improvements.
And first, as to the highest department, Botany. Before the sexual
system of Linnæus was fairly established, (though it spread far
and wide by the literary labours of Hudson, Lee, Curtis, and
several other able contemporary writers, both in England and on
the continent,) defects were found in it, and not only as to the
terms of distinction, but also to its bringing together, in the
classification, plants which appeared, from their [p270] exterior
habit and qualities, to have no natural affinity to each other. This
Linnæus was aware of himself, and left some fragments of a natural
arrangement, but which he did not live to complete. This, or the
idea of it, however, was taken up by Jussieu, a French botanist, and
completed as far, perhaps, as it can be; and though, in our present
botanical publications, both systems are continued, yet it is likely
that Jussieu’s simplified system will, in time, supersede the other,
though the curious fact on which that of Linnæus was founded will
never be forgotten, because of its practical use in the amelioration
of fruits. Botanical publications, under the various names of
Hortuses, Floras, Monographs, and of every country and district
under the skies, and since the promulgation of Jussieu’s system,
monographs, under the titles of Geraniaceæ, Cistineæ, &c., flow in
periodical floods from the press, crowd the bookseller’s shelves, and
thence find their way to every elegant drawing-room in the kingdom.
This additional call on the business of the press, as well as upon
the talent of the artist, arises from the fashionable and refined
bias of the public taste for this rational and delightful study.
To extend botanical collections, and the desire to possess every
vegetable beauty, pervaded the whole community: hence expeditions to
distant lands by collectors; hence the extension and encouragement
of nursery business; hence have sprung up chartered societies and
associations for the encouragement of botany and gardening all over
the realm; so that vegetable beauties and curiosities are now to be
seen in British collections, from every region of the known world.
Neither has the occult subject of botanical physiology been
neglected; many curious facts connected with the organisation,
structure, functions, and qualities of plants, have been ascertained:
but still there remains much for the employment of the naturalist’s
mind on this difficult subject.
Landscape gardening is not so much “the rage” as it was twenty or
thirty years ago: national circumstances, perhaps, may be the cause;
but its principles are much better understood. The errors of Kent
and Brown, and their followers, have been corrected by the works and
writings of Repton, and the critiques of Knight and Price, whose
theories have been [p271] carried into practice by Loudon and
others; and nothing will prevent the universal adoption of their
principles, but the difficulty of giving the foreground from _home
walks_ the extreme degree of ruggedness so much admired, and even
indispensable to the painter. Fern, (unless we can introduce some
uncommon foreign variety,) burdock, kexes, cannot be admitted into
dressed ground; nor have we any plants in cultivation which would
well answer the purpose; true, we have the rhubarb, one or two sorts
of thistles, eryngiums, palma Christi, and gourds with their ample
leaves: but these would only appear intruders, and misplaced: but
much may be done by a judicious disposition of our common shrubs,
so as to conceal the traces of the spade and line, and give all our
combinations of land, wood, and water that flowing character, which
is so true to nature, and so pleasing to the refined eye of taste.
Floriculture, which has been imported from France and Holland, is
also intensely followed about London, as well as in our manufacturing
provinces. Authors have creditably appeared in this line too; and our
annual blows of flowers, both home-cultivated and imported, are at
once rich and costly. Tulips, hyacinths, narcissuses, ranunculuses,
and anemones, are the principal bed flowers: but roses, stocks,
dahlias, chrysanthemums, and even poppies, are out of number.
Flowering shrubs, both within and without doors, are eminently rich
and various, and astonish as much by the splendour of their colours
as by their elegant forms and number.
Orcharding has declined during the last fifty years: first, because
of the gradual deterioration of the trees, and precariousness of the
crops; next, from the improved way of agricultural labourers’ manner
of living. This change renders the use of small cider and perry less
necessary in a farm-house, causing an increased consumption of malt
liquor; and this again, occasioning a greater demand for barley, at
once pleases both the farmer and the Chancellor of the Exchequer.
Thus the cultivation of orchard fruit (except cherries[50]) has
greatly fallen off; and the decayed state of the old, and difficulty
of [p272] raising new orchards, has given a check to such exertion,
except in places at a distance from the metropolis, where orchards
have suffered less from decay, and where the habits of the cider
drinkers are more inveterate. Mr. Knight, the President of the
Horticultural Society, has written copiously on this subject, and
very properly considers the cultivation of orchard fruit as a
national object; and by his example has done as much, nay, much more,
than any other gentleman in the kingdom, to restore our orchards
to what they used to be, and what they may be,—and it is hoped his
excellent instructions will not be thrown away.
Kitchen-gardening, the most important and useful branch of the
subject, next demands attention; and here we are gratified with
a fine display of the efficacy of perseverance, the success of
experience, and the triumphs of skill. In every month of the year, in
spite of the winter’s frost or summer’s sun, our tables are supplied
with wholesome and agreeable vegetables:—of roots we have fourteen
sorts; of stems, shoots, and leaf-stalks, seven; of leaves, eight; of
flowers, four: of culinary fruits we have sixteen; of seeds and pods,
six; of condimental herbs we have twenty-nine; and of herbs and seeds
for confections there are seven, besides various fruit: of roots,
leaves, flowers, and fruit, for salads, there are in cultivation
twenty-two kinds; and various sorts of plants for medicine and
distillation.
Of table-fruit there are above twenty different species, and of
these numberless varieties, extending to several hundreds, or even
thousands, of various excellency and value.
A few tropical and foreign fruits, not included in the above, have
been cultivated in tolerable perfection in Europe within these few
years, viz. the Chinese loquat and litchee, the custard apple,
mangosteen, and mango, &c.; and there is no doubt, if these fruits
could be worked on some hardier kindred stock, and a suitable place
formed for them in a stove, they might be cultivated with the same
success as the anana.
In the forcing department of gardening, wonders have been
accomplished. By this application of art, we appropriate to ourselves
an almost perfect imitation of any of the warmer [p273] climates:
heat, that powerful agent in the development of vegetation, we can
have in any degree, by stoves, by fermenting substances, and from
the steam of boiling water: light, a no less necessary agent in the
maturation of fruits, we combine with the former, by glazed houses
and frames.
The various expedients for obtaining the necessary degree of heat,
are, first, the most simple method of a stove, with its flue passing
through or round the floor of the house, and this for warming the
air within; but in this case, as the roots of the plants do not
sufficiently, it is supposed, receive the proper degree of heat,
various fermenting substances, as recent stable-yard dung, tanners’
bark, oak and other leaves of trees, &c. are formed into beds, on
which the compost of earth is placed, as in hot-bed frames, or in
which the pots containing the plants are placed, or plunged, as in
a hot-house. To obtain the same effect, borders within houses are
formed for the roots, having an excavated heat-chamber beneath,
supplied by simple stove flues, or from the fermenting substances
above named, or from steam admitted for the purpose. This mode of
supplying an equal degree of heat to the roots, as well as to the
leaves and branches of a plant, is plausible, and cannot be far
wrong, because it has been attended with success: but there is,
perhaps, more attributed to it than it deserves, because the region
or stratum of the soil, which is naturally occupied by roots,
differs, in respect of temperature, much less over the whole surface
of our globe, than is commonly imagined. The heat of the air in
different latitudes ranges from several degrees below zero to 110
degrees of Fahrenheit’s scale; but the temperature of the earth
eighteen inches below the surface, it is probable, does not vary
more than ten or fifteen. In England spring water varies only two
degrees, viz. from 42 degrees in summer to 40 degrees in winter; and
the effects of our hardest frosts very rarely penetrate deeper than
nine inches; but it is necessary to observe, that, in such cases,
as well as in hotbeds, we _force_ as well as defend; and probably,
by such mode of applying heat and moisture, nutritious gases may
be communicated, which may be no small advantage. Besides, the
atmosphere of the house can (as is done) be impregnated with the same
qualities and degrees of heat and humidity [p274] (a most necessary
accompaniment[51],) which may be generated below.
Light is a most potent agent in the maturation of vegetables:
united with a moderate degree of cold, it is much more effectual
in progressive vegetation, than the necessary degree of heat with
darkness. Exposure to light is indispensable to plants: and,
therefore, our glass cases are formed to admit as much as possible.
Within these few years, the endeavour to gain an accession of light
by reducing the dimensions of the wooden scantling of hot houses
suggested the idea of metallic frames; and for the concentration of
the sun’s rays, horizontal as well as vertical curvilinear roofs have
been constructed. Lightness to the eye, durability, imperceptible
expansion, and glazed with panes, cut like segments of circles, to
facilitate the passing off of condensed water, with complete command
of ventilation, are an assemblage of properties, always as desirable
as necessary; and as they may be cast in the most elegant forms,
and protected by paint, they add greatly to the ornament of the
garden. Beautiful as these buildings are, some little disappointment
has taken place respecting them: it has been experienced, that the
intensity of the sun’s light, or heat, has been found detrimental
to the tender inmates, and that shading is as necessary in bright,
as light is in cloudy weather. Certain it is, that in the winter
season, when light and heat are most desirable, no fear need be
entertained from this circumstance; and it ought to be considered,
that in our summer, we have at least, daily, _four hours_ more sun
than intertropical plants have at home: of course, they have less
time for their evening’s repose, (which all plants more or less
require); besides, it should be thought of, that all plants are not
equally formed to sustain such a blaze of light; “some affect the sun
and some the shade;” such as the pine-apple[52], and orange, which
require “a warm [p275] shade;” and perhaps all plants which present
a large reflecting surface of foliage to the sun, are content with
a smaller share of his direct rays. These observations attended to,
sun-shades may be applied for occasional use, and with the plants at
a proper distance from the glass, will certainly secure them from all
the inconvenience of such buildings, while none of the advantages are
lost.
The kitchen-garden range of buildings includes pine-stoves, vineries,
houses for peaches, and nectarines, figs, and cherries, hot-walls,
pits for succession pines, melons, cucumbers; besides store pits for
roots, tender vegetables, salading, &c., as well as frames for many
purposes of cultivation. Mushrooms are usually raised in sheds behind
the houses. The hot-houses are also used for growing early culinary
vegetables, and small fruits in pots.
[To be continued.]
FOOTNOTES:
[48] The cocoa palm is rather a gigantic herb than a tree: the stem
rises to a great height, of a strongly tough fibrous substance, but
never so indurated as timber, though it is used in the construction
of houses. It has no branches; but is crowned with from five to
seven ample compound leaves, forming an umbrella-like head. The
spatha issues from the centre, and soon falls pendent between and
below the footstalks of the leaves, where it flowers and ripens the
fruit. The nut is enveloped in a thick brown fibrous husk, which
opens to shed it when fully ripe. The nut, when opened, yields
two liquids, which are nutritious, and accounted delicacies: the
first is the milk which runs out; the next is the cream which is
procured by being scooped off the kernel with a spoon: this is of
thick consistence, and much resembles the cream of milk. After
these remains the perfectly-formed layer of kernel attached to the
shell, and which is used along with the liquids as an article of
food. But another most pleasant beverage, called toddy, is obtained
from this palm, and which constitutes the chief value of the plant.
The fruit is sacrificed to procure this; soon as the frond becomes
pendent, the extremity is cut off, and a narrow-necked vessel is
slung thereto to receive the streaming sap. This, both before and
after being fermented, is an agreeable and refreshing drink. It also
yields an ardent spirit by distillation, but of which the natives
deny themselves the use.
[49] In Martin’s painting of the Paphian Bower, though a fine
composition, the roots of the tree, on the left of the foreground,
are too much out of the ground. The accidental exposure of roots
on the bank of a stream, or high-road, and their buttress-like
departure from the trunk, are legitimate objects for the pencil; but
their ramifications pourtrayed on the surface of the ground, is as
ridiculous as unnatural.
[50] It is said that many of the Caroon cherries brought to
Covent-garden market, are bought up for the purpose of colouring
wine on the Continent.
[51] The admission of humidity into forcing-houses is attended by
the most salutary consequences: it counteracts the bad effects
of fire-heat, and is inimical to many insects. For this purpose,
a steam-supplying apparatus is added to the best-constructed
hot-houses, productive of the greatest advantages.
[52] It has long been observed by gardeners, that the pine-apple
always does best in forcing-pits, merely from the circumstance of
there being more shade.
_Chemical Manipulation, being Instructions to Students in Chemistry,
on the Methods of performing Experiments of Demonstration, or of
Research, with accuracy and success By_ Michael Faraday, F.R.S., &c.
We will not positively assert that no one except Mr. Faraday could
have written this book, but we are of opinion that there are very
few chemists adequate to such a task, which has manifestly required
a considerable share of practical skill, much deep and theoretical
knowledge, and no small degree of patience and perseverance,
more especially shown in the clearness of the details, and the
perspicuous manner in which he has managed to describe prolix and
difficult processes. The work moreover fills up a chasm in chemical
literature, by embodying almost all that is important relating to
chemical manipulation scattered through the writings of others;
while the author’s extensive experience has enabled him to correct
their faults, and to present the student and operator with many new
and important facts and processes, by which the researches of the
laboratory are most essentially facilitated.
Such is our general opinion of the treatise before us, and we are
persuaded that those who are capable of appreciating its merits will
agree in our decision; but it is not so easy to [p276] substantiate
our judgment by quotations, in consequence of the general didactic
character of the book, and the mutual dependence and connexion of
its different parts. We shall attempt, however, to give the general
reader an outline of its contents, and point out such parts to the
chemist as we conceive particularly useful and worthy attention.
The importance of readiness and dexterity in the performance of
experiments has been duly estimated for more than a century. The
writings of Black, Cavendish, Priestley, and especially Scheele, as
opposed to those of their predecessors, show that they had acquired
considerable facility in attaining, by simple and economical means,
those ends which had before consumed much time and much expense
in their accomplishment: but it is only of late years that the
refinements of manipulation have been carried towards perfection;
and the researches carried on in the laboratory of the Royal
Institution have been not a little conducive to this improvement:
to no one, however, is this part of the science more indebted than
to Dr. Wollaston, whose skill in what may be called microscopic
chemistry is consummate, and who has a host of humble but industrious
imitators. So essential, indeed, is the attainment of correct
methods of manipulation to the progress of chemical science, that
many entire trains of research are exclusively dependent upon it for
success. It is true that it must always be subordinate to genius and
invention; yet the person who could only devise, without knowing how
to perform, would comparatively be able to lend little aid to the
extension and usefulness of knowledge: and were it not an invidious
task, we might be able to show that some of the greatest discoveries
and improvements of the science have originated in dexterity of
experiment, rather than in profundity of design. By tact, therefore,
in manipulation, a considerable advantage is gained, independent
of that resulting from an acquaintance with the principles of the
science; and this is so considerable, that, of two persons of
equal talent and information in other respects, he who is the best
manipulator will soon be in advance of the other; the one will draw
just inferences with accuracy and rapidity, while the other will be
lost in doubt, and often led into error. Mr. Faraday has pointed out
several other cases of prominent advantage, arising from skilful
manipulation, especially when very small quantities of matter are to
be operated upon, and where accurate conclusions are of more than
ordinary importance, as in testing for arsenic and other poisons
on judicial occasions. When the substance under examination is
rare, [p277] as often happens, the facility of working with small
quantities is also of much importance, as otherwise the opportunity
of gaining information may be lost, or only retained at great
expense. “There existed,” says our author, “in the British Museum
a small fragment of a black stone, the source and history of which
was unknown: it was unique, no other specimen being in the Museum,
or known to be in existence; yet as it presented some peculiar
characters, Mr. Hatchett was induced to examine it, and, working with
a portion of the stone weighing not more than two hundred grains, he
was enabled to discover in it a new metal, which he distinguished,
by its various characters, from all those previously known, and
which he named Columbium. Ekeberg afterwards discovered a metal,
which he named Tantalium, conceiving it to have been observed and
distinguished for the first time by himself; but Dr. Wollaston, who
examined it, and compared it with columbium, was able to identify it
with that metal, although he had not more than five grains of the
stone from the British Museum upon which to make his experiments.”
In short, there can be but one opinion respecting the first-rate
importance of expertness in manipulation, and neatness, dexterity,
and efficacy of experimenting. These are the subjects to which
the present volume is directed, and which will, therefore, form a
valuable accompaniment to the more general and systematic works. They
are discussed under the following general heads:—
_The conveniences and requisites of a laboratory_.
_Chemical apparatus, and its uses_.
_The methods of performing chemical operations_.
_The facilities acquired by practice; and,_
_The causes which make experiments fail or succeed_.
The description of a laboratory is followed by two long and
well-written sections on the arts of weighing and measuring, in which
the account of the methods of determining specific gravities, and of
the general management of a delicate balance, are well deserving the
student’s attentive perusal: indeed, there are no operations which
are more frequently performed in a slovenly and careless manner, than
those in which scales and weights are concerned; and we should advise
the tyro to sit down with his balance and this book before him, and
practise the manipulations which it explains.
The fourth section, on the sources and management of heat, is devoted
to the construction and management of different kinds of furnaces,
lamps, blowpipes, thermometers, and pyrometers, and abounds in useful
hints, and in the details of [p278] practical information; and
the same remark applies to the succeeding sections on comminution
and solution—indeed, we were surprised at finding so much to be
taught in regard to these very simple operations. The seventh,
eighth, and ninth sections treat of distillation and sublimation,
precipitation, and filtration. Here, and indeed throughout the work,
the wood-cuts are particularly distinct and well executed. In the
section on crystallization, the uses of that process are enumerated;
and to this succeeds an account of evaporation. All these operations
are extremely well investigated and described, both as to their
principles and as to the most proper means of effecting them; a
number of curious circumstances are pointed out, by which their
results are influenced, and by which certainty and success may be
insured.
The uses of coloured tests are explained and illustrated in the
twelfth section. Of coloured liquids the author chiefly recommends
the infusion of red cabbage; and as it is not only a very good test
for private experiments but of excellent service to the public
lecturer in rendering certain changes of composition visible to
an audience, it may be worth while extracting the directions for
preparing it.
“583. The only substance of the kind, perhaps, worth keeping in
solution, is an acid infusion of red cabbage. For its preparation,
one or more red cabbages should be cut into strips, and boiling
water poured upon the pieces; a little dilute sulphuric acid is to
be added, and the whole well stirred: it is then to be covered and
kept hot as long as possible, or, if convenient, should be heated
nearly to boiling, for an hour or two, in a copper or earthen
vessel. The quantity of water to be added at first should be
sufficient to cover the cabbage, and the sulphuric acid should be
in the proportion of about half an ounce of strong oil of vitriol
by measure to each good-sized plant. This being done, the fluid
should be separated and drained off, and as much more hot water
poured on as will cover the solid residue, adding a very little
sulphuric acid. The whole is to be closed up, and suffered to
stand until cold, and then the liquid poured off and added to the
former infusion. The cabbage may now be thrown away. The infusion
is to be evaporated to one half or one third its first bulk, poured
into a jar, allowed to settle, and the clear red fluid decanted
and preserved in bottles. The residue may have water added to
it, the solid part be allowed to subside, the clear liquor drawn
off, evaporated and added to the former, or it may be dismissed
altogether. This solution will keep for a year. When [p279] required
for use, the acid of a small portion of it should be neutralized
by caustic potash, or soda, (not by ammonia,) when it will assume
an intensely deep blue colour, and will, in most cases, require
dilution with twelve or fourteen parts of water. The red liquor of
pickle cabbage will, occasionally, answer the uses of the solution,
and is, when required for service, to be neutralized in a similar
manner.”
For test-papers, litmus and turmeric are the most essential, and
several precautions in preparing and using them are here pointed out,
which, though apparently trivial, are, in fact, extremely important
in insuring correct conclusions. We transcribe a part of the account
of the applications of these coloured papers, as a specimen of the
clear minuteness with which the details of the work are given, and as
a sample of the author’s general method and style, where subjects of
much greater intricacy are to be explained.
“591. In using these test papers with a fluid suspected to contain
free acid or alkali, or knowing that one of these substances is
predominant, to ascertain which is so, all that is necessary is to
moisten them with the liquid, and observe the change: if the fluid
be acid, the blue colour of the litmus will immediately become red;
if alkaline, the yellow colour of the turmeric will be changed to a
brown. The moistening may be effected by dipping the paper into the
liquid; but a better method is to touch the edge of the slip with
a rod dipped in the fluid. In the latter case there is no risk of
contamination to the fluid from the paper, and only a very minute
quantity of the liquid is used at once.
“592. These trials must be made by day-light; artificial light not
permitting that just estimation of the changes by which the presence
of a small excess of acid or alkali is to be determined. As the
proportion of free acid or alkali diminishes, the intensity of the
new tint produced upon the paper is also diminished; and when in
very small quantity, it requires considerable attention before a
decision can be arrived at. The test paper should occasionally be
touched with pure water in the immediate neighbourhood of the part
where the solution has been applied, for any change in appearance
that may have occurred, not due to mere moistening, is then readily
perceived.
“593. Although acid is generally tested for by litmus paper,
and alkali by turmeric paper, yet the former is sometimes used
advantageously for the latter purpose, being first slightly
reddened, either by exposure to the air, or by momentary contact
with muriatic acid fumes. When the [p280] paper thus modified is
used to detect a free alkali, instead of turmeric paper, that
substance is indicated by the restoration of the original blue
colour. Litmus paper is best slightly reddened for this use, by
putting a drop or two of muriatic acid into a large jar, allowing
it to stand a few minutes, and then bringing the paper towards the
mouth of the jar, or carefully placing it within: so soon as the
blue tint has become slightly reddened, the paper should be removed
for use. If too much acid be imparted to the paper, the delicacy
of its indications is injured, because of the greater quantity of
alkali required to neutralize the acid, and restore the blue colour.
For the same reason a paper free from alkali or carbonate of lime
has been recommended for the preparation of these tests: for these
impurities, combining with a minute portion of acid, neutralize it,
and thus prevent that delicacy of indication which the test paper
ought and may be made to possess.”
The mode of determining the value of alcaline substances, or
“alcalimetry,” is described at length in this section. Our readers,
however, will here recollect that there is an error respecting the
specific gravity of the acid, which Mr. Faraday has corrected at page
221 of the present volume of this Journal. The thirteenth section
is allotted to crucible operations, and the fourteenth to furnace
tube operations. They are full of minute and admirable instructions,
evidently deduced from long experience, and detailed with the
same precision and clearness which we have already eulogised. The
fifteenth section, which occupies nearly a hundred pages, relates to
“pneumatic manipulation, or management of gases.” Every paragraph of
the instructions here given will be found to contain something of
importance to the student; it is, indeed, a valuable essay upon a
difficult and nice department of chemical research.
Under the head “Tube Chemistry,” in the sixteenth section, a
variety of means are pointed out, of working with and employing
glass-tubes, as substitutes for more expensive and formal apparatus.
Indeed, the young chemist cannot do better than practise the art of
bending, drawing out, and sealing tubes, as here directed, (and in
the nineteenth section,) by which he will soon gain the requisite
dexterity in forming them into test tubes, retorts, and so on, and
be enabled to furnish his laboratory with a quantity of very useful
vessels and apparatus, at a very moderate expense.
The application of electricity to chemical purposes forms the subject
of the seventeenth section, in which the [p281] management of
electrical machines and apparatus is described, and the circumstances
necessary to facilitate investigation and insure success are pointed
out. To this succeed the management and composition of lutes, and a
chapter on bending blowing, and cutting glass.
Cleanliness, order, and regularity are of the utmost importance in
the laboratory; and though the appearance of the chemist himself
is often such that he appears “to doat upon dirt,” the strictest
nicety must generally be observed in the state of his utensils and
apparatus. These matters must, indeed, generally engage his personal
attention; and it is not sufficient that glasses and other vessels
be merely washed and wiped in the usual way, but they are generally
required to be free from the minutest portions of adhering matter.
A section is accordingly appropriated to the subject of cleanliness
and cleansing, in which, and in that which follows it, entitled
“General Rules for young Experimenters,” much information is conveyed
that will prove useful to those who are commencing the practice of
experimental inquiries in chemistry, and also to such as, having made
some progress, have indulged themselves in slovenly habits. Macquer’s
observations on this subject, as quoted by our author, are so much
to the purpose, and so well deserving the serious attention of the
young chemist, that we shall stand excused for inserting them in this
place. He says, “A persuasion must exist that arrangement, order,
and cleanliness, are essentially necessary in a chemical laboratory.
Every vessel and utensil ought to be well cleansed as often it is
used, and put again into its place; labels ought to be attached to
all the substances, mixtures, and products of operations which are
preserved in bottles or otherwise; these should be examined and
cleansed from time to time, and the labels renewed when required.
These cares, although they seem to be trifling, are, notwithstanding,
the most fatiguing and tedious, but the most important, and often the
least observed. When a person is keenly engaged, experiments succeed
each other quickly; some seem nearly to decide the matter, and
others suggest new ideas; he cannot but proceed to them immediately,
and he is led from one to another; he thinks he shall easily know
again the products of his first experiments, and therefore he does
not take time to put them in order; he prosecutes with eagerness
the experiments which he has last thought of, and in the mean time
the vessels employed, the glasses and bottles filled, so accumulate
that he cannot any longer distinguish them; or at least he is [p282]
uncertain concerning many of his former products. This evil is
increased, if a new series of operations succeed, and occupy all the
laboratory; or if he be obliged to quit the place for some time,
every thing then goes into confusion. Hence it frequently happens
that he loses the fruits of much labour, and that he must throw away
almost all the products of his experiments.
“The only method of avoiding these inconveniences is to employ the
cares and attentions, above mentioned. It is indeed unpleasant
and very difficult continually to stop in the midst of the most
interesting researches, and to employ much valuable time in cleaning
and arranging vessels and attaching labels. These employments are
capable of cooling and retarding the progress of genius, and are
tedious and disgusting; but they are nevertheless necessary. Those
persons whose fortunes enable them to have an assistant operator,
on whose accuracy and intelligence they can depend, avoid many of
these disagreeable circumstances; but they ought nevertheless to
attend to the execution of these things. We cannot depend too much
on ourselves in these matters, however minute, on account of their
consequences. This becomes even indispensable when the experiments
are to be kept secret, at least for a time, which is very common and
often necessary in chemistry.
“When new researches and inquiries are made, the mixtures, results,
and products of all the operations ought to be kept a long time
well ticketed and noted. It frequently happens that at the end of
some time these things present very singular phenomena, which would
never have been suspected. There are many beautiful discoveries
in chemistry which were made in this manner, and certainly a much
greater number which have been lost, because the products have been
thrown away too hastily, or because they could not be recognised
after the changes which happened to them.”
The uses of equivalents, and the method of employing Dr. Wollaston’s
scale, form the subject of the twenty-second section of Mr. Faraday’s
book; and of the concluding sections, the twenty-third contains
a quantity of miscellaneous remarks, and the twenty-fourth is
appropriated to “a course of inductive and instructive practices;”
that is, to a selection of minute instructions respecting the use of
instruments, and the performance of operations.
Such is an outline of the contents of this volume, of which we
have felt ourselves obliged to speak in terms unequivocally [p283]
favourable; in fact, it contains, strictly speaking, nothing to
criticise. It is minute, laborious, and very unpretending, and
contains a body of instructions for the performance of experiments,
and of descriptions of the modes of managing and applying apparatus,
which is not to be had elsewhere, being manifestly derived from
diligent research, extensive experience, and correct judgment. It
is not a book for amateurs; for they will presently learn from it
that there is no royal road to the science of which it treats; but
the real student, who will seriously follow its laborious details,
will discover in them an acceptable and sure guide through the
crooked and intricate, as well as the straight paths of chemistry.
Those, however, and those only, who are well versed in the business
of the laboratory, both as experimentalists and teachers, can duly
appreciate the weighty service which Mr. Faraday has here performed.
_Statistical Notices suggested by the actual State of the British
Empire, as exhibited in the last Population Census_. Communicated by
Mr. Merritt.
[Read before the Literary and Philosophical Society of Liverpool.]
The population returns of the _decennial lustrum_, or period of
ten years, which ended in 1821, were delayed for a considerable
time, on account of the difficulties which have always occurred in
taking the population of Ireland. They have now, however, been some
time completed, and from the _data_ they afford, a few reflections
naturally present themselves, which though sufficiently obvious, yet,
from the extreme interest of the subject, may be thought deserving
of being brought together, and exhibited in a connected form. They
point out some peculiarities in the situation of this country, which
distinguish it from almost every other nation that has yet existed in
ancient or modern times.
From the notices which have been published respecting the different
districts, it may be inferred, that the portion which may be termed
the _Urban_ population, has augmented in a much greater degree
than the _Rural_. The general ratio of increase has, however, been
very great, and, in the opinion of Mr. Malthus, still continues at
the same rate. That eminent [p284] economist has lately given it
as his opinion, before the Emigration Committee, that the present
inhabitants of the British Islands do not amount to less than
twenty-two millions and a half. This estimate is perhaps a little
exaggerated; but as it may be assumed sufficiently near the truth for
all the objects of general speculation, I shall proceed to point out
a few of those leading peculiarities, to which I have just alluded.
In the first place we may assert, I apprehend, on sufficient grounds,
that Great Britain is the most populous nation which has existed
since the Christian era. No other instance has occurred in which an
extent of continuous surface of 93,000 square miles has sustained
a population of twenty-two millions. Italy, which is not of much
greater extent, has sometimes been rated at nearly the same amount,
but this estimate has been formed in the absence of all actual
enumeration and is now ascertained to be a considerable exaggeration.
No other part of the world can enter into the competition, unless it
be certain districts of China and Japan, but which, as our knowledge
of them in this respect is quite uncertain, I shall leave wholly out
of the question. How far some nations of the ancient world may have
approached or gone beyond us in the race of population, is perhaps
equally lost in uncertainty. There is reason to believe, as I have
endeavoured to demonstrate on another occasion, that some districts
of the old world exceeded, in this respect, any country of modern
ages. Amongst them, perhaps, may be reckoned Egypt, Mesopotamia,
the lesser Asia, and some parts of Persia: but certainly, neither
in ancient nor modern times do we find any instance of a single,
compact, distinct empire, exactly defined, identically governed, and
peopled by twenty-two millions of souls on the same extent of soil;
this is undoubtedly a peculiarity the most striking which can exist
among nations.
In the second place, we may, I think, affirm with tolerable
certainty, that no nation ever contained so many large cities. On
this point Great Britain exhibits a splendid superiority. We have
two cities of the first class, London and Dublin; the one with a
population of more than a million, the other with little less than
three hundred thousand. Of cities of the second class, or those which
reach one hundred thousand inhabitants, [p285] or above that number,
we have seven, _viz._, four in England, Manchester, Liverpool,
Birmingham, Bristol; two in Scotland, Edinburgh and Glasgow; and
one in Ireland, the city of Cork. These seven average considerably
more than one hundred thousand each. We have fourteen towns of the
third class, or those containing from thirty to fifty thousand
or upwards of inhabitants, _viz._, ten in England: Portsmouth,
Plymouth, Norwich, Leeds, Sheffield, Nottingham, Bath, Newcastle,
Coventry, and Hull. Two in Scotland, Paisley and Dundee, and two
in Ireland, Belfast and Limerick. Of towns of the fourth class, in
which are usually reckoned those of from fifteen to thirty thousand
inhabitants, we have at least thirty, and probably more. A slight
glance at the principal nations of Europe, with this view, will show
at once their immense inferiority.
To begin with France, the most populous of the great sovereignties.
That empire possesses only one city of the first class, _viz._ Paris,
which is inferior to London by one third. She has five of the second
class, _viz._, Lyons, Bourdeaux, Marseilles, Lisle and Rouen; but,
according to the latest information which I have been able to obtain,
they will not reach, by a very considerable proportion, the average
number of the seven English cities of the same class. France has also
eight towns of the third class, _viz._, Amiens, Caen, Nantes, Brest,
Toulouse, Toulon, Mentz, and Versailles. I am not quite sure, as no
census has lately been taken, whether two or three of the following
towns ought not to be included in this class, though I am inclined,
on the whole, to a contrary opinion, _viz._, Melun, Montpelier,
Nanci, Dijon, Tours, Rennes, and Troyes; they will not, however, I am
persuaded, come near the average of the British third-rate towns. The
same remark will hold as to the number and size of the inferior towns.
With respect to the rest in rank of the great monarchies, the
Austrian Empire, a very few words will suffice, as it cannot pretend
to come into any competition with us, on the point in question.
Austria possesses only one city of the first class, and three of the
second, _viz._, Vienna, Prague, Milan, Venice. The towns of the third
rank are proportionably few. With Spain, Russia, and Prussia, it
would be idle to enter into any comparison. [p286]
It must be confessed, however, that the present kingdom of the
Netherlands, as established by the congress of Vienna contains,
in proportion to its extent and population, more large towns than
any single state which now exists, or perhaps has ever existed.
With an extent of territory and number of inhabitants scarcely
exceeding, one-fourth of the British dominions, that kingdom has one
city the first class, Amsterdam; two of the second rank, Rotterdam
and Brussels; and probably as many of the third class as Great
Britain herself. But the Kingdom of the Netherlands is in itself
too insignificant to enter into any competition with such a state
as Great Britain for any objects of general comparison. The various
states comprehended under the common geographical appellation of
Italy, if that superb country was united under one head, is the
only one of the European nations which, under the view we are now
considering, could sustain any parallel with Great Britain. But
this union, so desirable in many points of view, would probably
diminish its pretensions as a nation of large cities. Many of these
have reached their present grandeur and extent by having been long
the seat of a court or a government, and would perhaps decline
considerably if reduced to the rank of mean provincial capitals. But
even under any circumstances of territorial union, Italy could not
be held to comprize more than one city of the first class, _viz._,
Naples, and six of the second, _viz._, Turin, Milan, Venice, Genoa,
Florence, and Rome; whereas, as we have just seen, Britain has two
of the first and seven of the second, and these superior in size and
number of inhabitants.
The third peculiarity which I have to remark in the actual situation
of the British dominions is, that no nation ever had so great an
_urban_ population, or so large a proportion of its inhabitants
residing in towns. This peculiarity is intimately connected with
that which I have just described; but it is nevertheless a very
different characteristic. Great Britain is not only distinguished for
the number and size of her large cities, but for having so _great_
a number of them on so _small_ a territory. By the census of 1811,
it was found that nearly half our population resided in towns, and
at present, I apprehend, the proportion will be found still greater.
In this [p287] respect no nation has ever approached us. The French
economists were of opinion that not more than one-fourth of the
people of France lived in towns; and the later statists, who have
alluded to the subject, contend that a still greater proportion of
the population is rural. This will not appear exaggerated when it
is recollected that all the lower classes of that country subsist
principally on vegetable food, and that, consequently, the greater
part of the soil being under tillage, a great number of hands is
required for its cultivation. In Great Britain, on the other hand,
the inhabitants of all classes consume a great quantity of animal
food, and, of course, a great part of our lands, being in a pastoral
state, require a small proportion of occupants. In the kingdom of the
Netherlands, it is supposed about one-third of the inhabitants live
in towns: in Italy about one-fifth: in Austria, Spain, and Russia,
except the province of Siberia, where the abundance of manufactures
congregates the people in masses, not more than one-fifth. In Russia,
Sweden, and Norway, where, amongst the lower classes, nearly every
family is its own manufacturer, not more than one-eighth or one-ninth.
The fourth and last of these peculiar characteristics which I shall
remark, is, that no great nation ever employed so large a proportion
of its people in trade and manufactures. In speaking thus, I leave
out of the question the Italian and Flemish republics of the middle
ages, and the Hanse Towns, free cities, and United Provinces of later
times. I speak only of great and extensive countries. It will appear,
I doubt not, by the present census, that at least half our whole
population is employed in trade, commerce, or manufactures. This is a
feature altogether singular; a circumstance to which no parallel can
be found in the ancient or modern world.
From these premises, a few observations, in the way of corollaries,
will naturally suggest themselves.
In the first place, such a state of things is indicative of great
wealth and power. A country thus situated is, beyond any other,
powerful for attack and strong for defence. A profusion of great
cities can only be produced by extensive trade, and can only be
maintained by a highly cultivated soil. The wealth acquired by
the industry of the towns, reacts on the [p288] industry of the
agriculturist, and it is in this that the real advantages of commerce
primarily consist. In this way an extensive population is gradually
generated, for no maxim or political economy is now more generally
admitted, than that population is sure to follow close and to press
hard against the means of subsistence. An affluence of inhabitants on
a comparatively small territory, is, itself the primary ingredient
of power, and this first requisite of strength is, in the case of
Great Britain, essentially corroborated by our insular situation.
Surrounded by dangerous coasts and tempestuous seas, we can only be
approached at certain points and certain times; whilst, on the other
hand, as this state of things supposes and supports a powerful navy,
we are able in a great degree to choose our point of attack.
From a population such as we have described, of which only a very
limited part is employed in creating the means of actual subsistence,
a very considerable portion may always be abstracted for purposes
of attack or defence. It is usually calculated, that one-fifth part
of the inhabitants of every country is capable of bearing arms. On
this calculation, Great Britain contains four millions of fighting
men, of whom it is believed one million might be formed into an army
without any very serious interruption to the essential operations
of agriculture and commerce. This supposition may seem a little
extravagant, but it must be recollected that, at one period during
the late war, the number of men under arms was actually calculated at
seven hundred and fifty thousand.
In the second place, such a state of things is favourable to public
liberty. The congregation of men in great masses is found to give
great force to the influence of public opinion; by the spirit of
discussion which it generates; by the anxiety for intelligence which
it diffuses; by the collisions of opinion which it engenders, and by
the facility of union which it affords. Nations purely or principally
agricultural are generally under a despotic government, especially
large states, for the maxim of _divide et impera_ is applicable as
well to internal as to external politics. Ancient Persia and Assyria,
and modern Russia and Poland, are instances in point. The fierce
and demoralizing tyranny of the feudal system, which, after [p289]
the destruction of the Roman monarchy, left scarcely any other
division of the people than those of tyrant and vassal, could only
be effectually broken by the rise of great towns. These communities
were alone competent to resist the aristocratical and subordinate
despotisms into which all the nations of Europe were subdivided, and
which, as is well known, overawed the throne, whilst they enslaved
the people. In confirmation of this, it may be remarked, that the
free republics of antiquity, as well as those of the middle ages,
derived the spirit which nurtured them almost entirely from the
capital city; and though, in the former case, there was scarcely
any commerce to excite the activity of the people, yet the mere
congregation of a numerous body of men sustained the power of public
opinion.
But the most important question remains behind. Is a civil community
thus constituted favourable to individual virtue and happiness?
This is assuredly the point which it most behoves us to ascertain,
since no truism is more obvious than that power and opulence, and
refinement and splendour, and even liberty itself, are only so far
valuable as they tend to make men wiser, and better, and happier.
Is it true, then, that Great Britain has anteceded other nations in
these fundamental points, as much as in those we have just described?
This question cannot be answered without some hesitation: for we may
say, with Addison’s facetious Knight, “that a great deal may be urged
on both sides.” On the one hand it is certain that our situation is
eminently favourable to intellectual improvement. The increasing
spread of instruction, and the rapid advancement of knowledge which
are necessarily concurrent with our career of prosperity, must
ultimately advance us in the scale of moral and rational agents. If
knowledge be power, it is also happiness; for communities as well as
individuals would all be happy if they knew how to be so. It is also
certain that the incessant struggles of competition and the strenuous
efforts for distinction which are always at work in an over-peopled
and highly refined country are favourable to the active virtues.
They operate amongst the higher classes to provide many objects of
laudable ambition; and amongst the lower, afford perpetual facilities
for bettering their condition, [p290] and furnish an incessant
supply of occupation, the want of which is sure to open the door to
the incursion of all the worst propensities and basest vices. They
bring into action all the resources of human ingenuity; all the
aids of fortitude and enterprise; all the trials of patience and
perseverance; all the equanimity demanded by the constant mutations
and rotations of fortune. It is not to be denied, moreover, that the
first-rate virtues of beneficence, charity, and hospitality, take
root and flourish with peculiar vigour in a commercial community. The
fluctuations of condition to which almost every man knows himself
liable, and the constant proximity of distress and opulence, offer
perpetual excitements to the benevolent affections.
These, it must be confessed, are important ingredients in the
composition of human happiness; but considerations not less momentous
present themselves on the opposite side, for every thing in human
affairs is on a system of compensations. It is not to be denied
that a state of society, in which one-half of the population is
congregated in towns, and nearly a moiety of this half crowded
together in enormous factories, is highly unpropitious to virtue, to
health, and to happiness. In these huge receptacles of human labour,
it would be absurd to expect that the women should be distinguished
for their modesty and propriety, or the men for their prudence,
temperance, and regularity. It is an unhappy law of human nature,
that the force of example is most prevalent on the side of vice. A
few depraved characters scattered amongst a multitude are commonly
found sufficient to corrupt the whole mass: hence we may always
expect to find, in the seat of a great manufactory, all the worst
ingredients of civilized society; all the base depravities of a
luxurious and opulent community, combined with much of the grossness
and rudeness of the savage state: in a word, all the corruptions of
high civilization without any of its polish. Nor is this mode of
life, generally speaking, more favourable to health and comfort than
to good morals. The constitution of the young is impaired, and their
growth retarded by excessive labour and close confinement. Those of
maturer age are glad to seek relief from the depressing effects of a
wearisome and monotonous labour, unwholesome air, and constant [p291]
restraint, in intemperate indulgence; and all the long train of
vices and miseries to which the poor are liable, follows of course.
Nor are their prospects for the future often such as to encourage
hope or stimulate exertion. The habitual improvidence of the poor
is aggravated in their case by the dangerous fluctuation of their
trade. Sometimes they are eagerly courted with high wages, and lavish
promises; at others, no employment is to be had, and not enough can
be earned, even by the most unnatural exertions, to sustain their
families. Nothing can be imagined more fatal to order, regularity,
and comfort, than these vicissitudes. Hence it commonly happens,
that, in the decline of life, these poor creatures are driven to
the sad resource of parish relief. It is moreover not one of the
least evils of the manufacturing system, that it has a tendency, in
prosperous times, to generate an excessive population, which, on any
great reverse, is suddenly thrown on the community as a superfluous
burden. The changes of a fashion, the caprice of public taste, or the
sudden interruption of a foreign market, will reduce thousands to
helpless and unexpected poverty.
It must, however, be admitted, that the picture of rural life has
also its unfavourable aspect. Those who retire into the country are
apt to find themselves somewhat disappointed in their expectations
of rustic simplicity and pastoral innocence. In situations where
every breath of air, and every feature of nature express nothing but
peace and love, they are a little surprised to see the selfish and
malignant passions at work in all their baneful activity; to find, as
in the purlieus of a court, the symptoms of “envy, hatred, malice,
and all uncharitableness.” Still we shall find that instances of
utter depravity and abandoned profligacy are of much rarer occurrence
than in great towns. In a village, every individual is known, and the
very consciousness of being conspicuous, creates a sense of shame
which is highly salutary. It has often been observed, that men in a
body will commit, and even justify, atrocities which no individual
amongst them would be capable of attempting, if not screened by the
shelter of a crowd. We find, accordingly, in the annals of Wesley
and Whitfield, that the great scenes of their operations are in
collieries, factories, [p292] mines, canals, and all the other
appendages of a great commercial and manufacturing nation. It was
there, according to Whitfield, that the “Arch Enemy” raised his
triumphant standard; it was there, that the harvest of lost souls was
ripe and abundant. But the most decisive proof of the comparative
purity of the rural population above that of the manufacturing
districts, is the fact that the single town of Manchester will
furnish ten times more criminal prosecutions than two Welch counties
which contain an equal number of inhabitants.
On the whole, I think we cannot escape the conclusion, that, though a
certain degree of commercial and manufacturing property is necessary
to stimulate the agriculture of a nation, and to call forth its
utmost powers of production, yet that it is not desirable that
this country should proceed much further in that dangerous career,
or increase still further the disproportion between its urban and
rural population. The late increase in our numbers is so rapid and
alarming, that I am afraid some positive checks (to use Mr. Malthus’s
language) of very terrible potency must soon be brought into action.
The forcible lines of Goldsmith, though that great poet knew
little enough of political economy, are applicable to the wise and
benovolent statesmen of all times—
’Tis theirs to judge, how wide the limits stand
Between a splendid and a happy land.
_On the Modern Ornaments of Architecture, &c._
In no age since the Augustan era of Rome, perhaps, has decoration
of the interior of dwellings been carried to greater excess than
at present; nor, since the days of the florid style of Gothic
architecture, has the exterior received more embellishment.
Architectural ornaments have generally been copied from the antique,
those especially which belong to the orders. Indeed there is a kind
of classical standard, which governs the architect in the execution
of public edifices, from which he cannot with propriety depart.
National, and regal emblems, wherever suitable, should always be
introduced in public buildings, and in those of a private or mixed
character [p293] all legitimate ornaments may be displayed. Of
this class the acanthus, vignette, the branches of the olive, and
leaves of the palm, the crown of laurel, the chaplet of myrtle, and
the wreath of roses, are all proper when judiciously introduced;
and the rose and honeysuckle flowers, and the folicles, trefoils,
cinquefoils, &c., which so often occur on sculpture and plaster work,
are also proper, because they are imitations of nature.
But in our present style of decorative execution, from the most
elaborate finishing of a regal palace, down to the pattern of a
milk-maid’s gown, there is such latitude taken in the display of
licentious fancy, that imagination itself is baffled to find anything
in the infinite variety of nature’s works, to which their designs can
be compared, or to which they bear the most distant resemblance!
It is really unaccountable, that the whole tribe of our artists,
the ornamental statuary, scagliolist, paper-stainer, weaver, chintz
and cotton printer, &c. should all be “straining their low thought
to form unreal” forms and figures; and striking out the most
intricate and complicated, to the utter neglect (except in very few
instances) of those numberless simple though transcendently beautiful
configurations, which everywhere appear in the works of nature.
This is surely a dereliction of all propriety, an exuberance of
grovelling taste which no consideration can excuse, nor reason
justify. In this age of refinement, good taste should be the guide
in all things where invention is necessary, and design requisite;
whatever is grotesque or fantastic, should be banished from our
labours of art, and the elegant forms of vegetable or animal nature
alone take their place.
If it be asked, how it happens that such obliquity of fancy (for
it cannot be called taste) should so generally prevail, the answer
is, were these pattern-mongers to copy from nature every body could
judge of their ability as imitators, and, if unfaithful, would decry
the artist; whereas, whilst bringing forth his nondescript and
nondescribable forms of imaginary figures, he escapes the lash of the
critic, which otherwise he would be subjected to. [p294]
It may be granted, that it is as ridiculous to form stone or plaster
flowers, as those geometrical frets and fanciful nothings which
are usually pourtrayed in architectural decoration: but it may be
answered that if any ornament be necessary, that of a nondescript
character is not more appropriate, as such, than natural forms would
be; and these latter having a name, and many of them an emblematical
character, may be often applied with a propriety which cannot belong
to the other.
The old fashioned tapestry, notwithstanding its sombre appearance,
was in its plan much more rational than the multifigurations of
our modern paper hangings. The first represented some historical
event or legendary tale, yielding some mental information, or it
taught perhaps a moral lesson—the eye was amused while tracing the
ideas of the ingenious sempstress; but in our ephemeral and gaudy
ten-thousand-times repeated _paper_ nothings, there is no design to
interest, nor combination to amuse the eye longer than a transient
glance. Even the Chinese, who, in all their decorative finishings
shew _rigidity_ itself, have escaped from tame mannerism in paper
hangings, by imitating, from the edge of the carpet to the ceiling,
all the gradations of turf, herbs, shrubs, and trees, upon a sky
ground, enriched with figures or rather portraits of flowers and
fruit, as well as beasts, birds and insects. This though it cannot
deceive the spectator for one moment in mistaking a fictitious
for a real scene, yet is certainly far superior to European
paper-upholstery, as it at least may introduce a knowledge of
natural history, which the latter has no pretension to, indeed seems
studiously to discard, as beneath imitation.
All this vitiated taste, or fashion rather, is to be regretted;
especially as it appears that those
Fancied forms which on the ceilings sprawl,
And shapeless frets which decorate the wall,
are just as expensive, and difficult of execution, as the most
elegant imitation of vegetable or animal configuration would be; and
surely when such variety of forms are presented to the artist, they
deserve to be copied as transcendently superior to the capricious
fancies of the most celebrated decorator, or of [p295] the most
splendid fashionable designs; either in the works of the sculptor,
scagliolist, &c. or the more insignificant designers of figured paper
or drapery. Indeed there can be no good reason why ox-heads and
garlands (now the days of sacrifices are past) should not be banished
from the frieze and entablature, to admit the far more appropriate
figures of foliage, fruit, and flowers, aquatic as well as
terrestrial, which every garden yields;—and for interior enrichments
of cornices, mouldings, &c., the curious and elegant forms of the
testacea, would afford beautiful copies for imitation.
In fine, if there be any merit or propriety in the adaptation of
whatever is elegant in form, beautiful in outline, harmonious
in tint and proportion, and congruous in combination, such may
readily be found in the animal and vegetable kingdoms. Faithful
representations of such objects, not only open a fine field for the
exercise of individual ability, at this time, but also a source
from which might be drawn a large share of public patronage, and
consequent commensurate reward. Indeed it is now pretty evident that
in many things, especially in the minor works of art, we have been
too long and too rigidly impressed with a veneration for the works
of antiquity, or what is equally benumbing, a passive following of
tyrant fashion; and that many a bright genius has been “nipped in
the bud,” and remained “twinkling in the socket” of Grecian and
Roman rules, who, if venturous enough to have burst the shackles of
professional thraldom, would have improved and elevated his art, as
well as himself, by designs and works which would have advanced his
profession and adorned his country.
But it is not yet too late; a knowledge and study of the genuine
elements of taste, whether of art or nature, and a mind embued with
rational perceptions of all that is beautiful and picturesque, and
grand or sublime in either, will rise superior to all precedential
fetters, as well as all modern mannerism, and will equally regard the
excellencies of the ancients, as it will avoid the errors of some
modern artists, who, in leaving the beaten track, have deviated far
and widely from the point to which good sense and good taste would
have led. [p296]
A list of plants, &c. which exemplify all that is elegant in
form, beautiful in outline and graceful in position, should have
accompanied the above imperfect remarks, but this must be deferred to
another opportunity.
J. M.
_De l’Influence des Agens Physiques sur la Vie. Par_ W. F. Edwards,
D. M., &c.
[Continued from the last Number.]
In our last number we presented our readers with a general abstract
of the first part of this valuable work. The second part refers to
animals of the _cold blood_ order, including _fish_ and _reptiles_.
The _larvæ_ of the latter underwent some comparative experiments
detailed in the first chapter, because they partake of the nature
both of _fish_ and _reptiles_, as to their _respiratory function_;
the imperfection of their intermediate state and developement of
organization not interfering with the objects in view, and the
double mode of aërification being exercised unequally. The _skin_
of these young animals furnishes them with the means of producing
the requisite changes in the blood by _absorption_, as in the
adult, while it lives in water; and the cutaneous respiration goes
on through this medium at a temperature which the subsequent more
perfect animal is unable to endure. The object entertained is the
influence of physical agents upon the changes which these animals
pass through in their form and structure.
An important condition of their advancement to maturity seems to be,
that the nutriment suspended in the water should be in very small and
limited proportions. Temperature also influences their constitutional
changes.
Sometimes the _larvæ_ pass through the winter in their primitive
state; a fact not generally known. Some _tadpoles_ were confined
within wooden boxes submersed in the river Seine, in which holes
were perforated to allow the stream to pass through, without the
possibility of the animals rising to the surface of the water, and
thus to inhale air. Others were placed in a large vessel of Seine
water renewed at intervals, with power to rise above the surface.
Ten in twelve of the first box underwent no transformation, the
others having gone partially through their change. But [p297] those
of the large vessel, and not submersed in the river, passed through
their changes of form without the least appearance of the phenomenon
being retarded. The running waters of the Seine probably contained
nutritious matter, which the water periodically renewed was more
deficient in.
Under circumstances of moderate nourishment and temperature, the
tadpoles under water did not complete their changes but in a very
partial and protracted manner, while the greater portion made no
change. The great difference in the circumstances of the experiments
seems to have been the access to the air of those which went
through their transformations as usual. Exclusion from light made
no difference in the results, and these were solely influenced by
occasional renewal of air from pulmonary respiration.
These animals possessing a double respiration, cutaneous and
pulmonic, that is, absorbing air from the water around them and
inhaling it from the atmosphere on its surface, renders these facts
highly curious. Fish possess only the means of aquatic respiration,
and the influence of temperature was tried upon them submersed in
water deprived of its air by previous boiling, the heat being varied
from 0° to 40°. The fish died quicker under these circumstances
than the frog species in the same situation; but their lives were
prolonged more in the _descent_ of the thermometer than during its
_elevation_, as also occurred with the experiments on frogs and
salamanders; and, in both cases, the younger the animal, the less it
could resist the higher temperatures. At 40° the young animals only
survived about two minutes, and the adults many more.
Fish were also submersed in closed vessels of aërated water, and, by
varying the temperature and the quantities of water, the duration
of their lives was augmented in proportion to the increased volume
of the liquid, the temperature remaining the same; but when these
experiments were conducted in open vessels, the contact with the
atmosphere altered the phenomena. At 20°, a small fish expired in
four hours; and when the temperature was lowered to 10° or 12°,
the same sort of animal lived several days; and when the water was
kept clean by being changed every twenty-four hours, the fish lived
indefinitely.
It is known that fish rise periodically to the surface of the waters
to respire; and Dr. Edwards discovered that they did so when they
have reduced the properties of the air [p298] dissolved in the water
to a lower standard than is requisite for the proper aërification of
their blood; thus renewing their supply of _oxygen_.
The functions of this class of animals have always been obscure; and
their phenomena are different from those of others. Different species
of fish die at various periods when deprived of water, some in a few
minutes, others in a few hours; and it appears that their dissolution
arises not so much from incapability of atmospheric respiration (for
the experiments of Sylvester prove that they can respire pure air),
as from the different state of the air.
Some experiments on _lizards_, _snakes_, and _turtles_ conclude the
researches among cold-blooded animals. The skins of these, like those
of the frogs and salamanders, received vivifying influence from
the air, mainly acting, in conjunction with pulmonary respiration,
to promote their existence. _Snakes_ and _turtle_, their pulmonary
respiration being insulated, from their skins being guarded from
atmospheric influence, were found alive; but the _lizards_ died
in a few hours, when the vivifying contact of the air was removed
from their bodies, and they breathed only by their mouths. Animals
naturally defended by _scales_ transpire much less than such as have
their skins free. Thus _frogs_, _toads_, and _salamanders_ yielded
more by perspiration than _lizards_, _snakes_, and _turtle_, in a
given time; and the porosity of the skin of course regulates the
facility of transpiration in all cases.
With these experiments and remarks, Dr. Edwards concludes the second
part of his researches. The third part includes _animals of warm
blood_, in which will be found some curious and interesting remarks
on the heat of young animals compared with that of adults.
Dr. Edwards refutes the common notion of young animals being
necessarily hotter than adults. The heat of young puppies was very
near that of the parent, or one or two degrees less, but this
variation was not constant. Some new-born kittens and rabbits were
also subjected to similar trials, and the results led to a conclusion
that the temperature of young animals is _less_ than that of adults.
According to these experiments, the power of resisting the cooling
influence of the air acquires force as the animal grows up; and those
examples related, in which artificial covering was adopted, show that
nudity is not the only cause of the reduction of heat, which is,
in fact, more referrible [p299] to their infantile constitution.
At first the sucking animal shows little variation from the parent
temperature; then this becomes more and more reduced, and about the
fifteenth day it is a degree or two below the mother.
Birds, which are warmer than mammiferæ, were next made the objects
of experimental inquiry, and the young recently hatched exhibited
a _lower_ temperature than the grown birds. After removal from the
shelter of their nests into a mild atmosphere of 17°, in one hour
they cooled down from 36° to 19°, thus losing 17° in an hour. At an
elevation of 22° the same results were obtained, and they cooled down
to within one degree of the surrounding air. The plumage of birds
has little if any influence upon their temperature. The production
of heat lies within, and not on the surface of the animal; and if
it be strongly developed, the removal of natural coverings does not
influence the heat produced; and if it be weak, their addition will
not prevent cooling. Birds recently escaped from the shell cooled
to within two degrees of the air, whereas the unplumed adult birds
scarcely lost one degree.
The distinctive character of warm-blooded animals to preserve an
uniformity of heat has no reference to _bulk_. The _eagle_ maintains
the same temperature as the _wren_ or the _tom-tit_, taking them at
the same age, and placing them under the same circumstances; but if
cooling measures be adopted, the lesser body parts with its heat
faster than the larger, though ultimately they arrive at the same
point. The dimensions of animals are infinitely varied; but the giant
reaches no higher standard than the dwarf, nor sinks to a lower
temperature.
In estimating the temperature of young animals, it must be taken
into account that they are born at different periods of organic
developement. Some come earlier into the world than others, and
some are more perfectly formed than others at their birth, and more
capable of helping themselves. This variation produces a different
standard of heat after birth, and especially creates a variety of
temperature among birds when tested at the same epochs of their
existence. The season in which animals are produced also modifies
their temperature.
The influence of age in modifying temperature is common both to
mammiferæ and birds. Young and healthy sucking pigs cooled faster
than their parent, their generating means of heat being more feeble.
Animals of warm blood possess [p300] the power of supplying heat at
its _maximum_ when first born; they then part with it by degrees,
and, as they advance in age, their heat becomes gradually augmented
again till it reaches the adult standard.
Dr. Edwards next proceeds to discuss the phenomena of animal
temperature more exclusively regarding adults, and especially among
those singular creatures of the mammiferæ which form an exception to
the general law of nature respecting the uniformity of temperature
as to warm-blooded animals. These beings are what are termed
_hybernants_, such as the _dormouse_, the _hedgehog_, the _bat_, the
_marmot_, &c., natives of Europe; which remain dormant during winter
without any external signs of life and motion. The change which
these undergo reduces them from the state of warm-blooded animals to
that of cold. Unlike the rest of their class, the autumnal season
lowers their temperature by degrees, till in winter it reaches so
low as to be scarcely higher than the surrounding air. Their powers
fail gradually, and their losses of heat are not repaired, till at
length their respirations become slow and feeble, and the heart
languidly urges the blood through the arteries. In this state there
is an imperfect aërification of the blood, and a partial state of
asphyxia, producing continued repose of the nervous and muscular
system. But the temperature of these animals sinks no lower than
the air, and remains sufficient to maintain a passive existence,
till the returning spring raises their heat again, and they become
lively and active till autumn; but even in spring these animals are
characterised by producing less heat than others of their class.
If we seek to know the cause of this curious variety, we can only
refer it to peculiarity of constitution, which is instituted by
nature as adapted to animals placed in situations of rigorous cold,
and where they cannot procure sustenance but in spring and summer.
Our author imitated the process of hybernation by artificial cold,
and produced the same effects; and when he restored animation by
gradual warmth, he found the animals as lively as before.
John Hunter and others have written on the natural history of
hybernants, and Dr. Edwards regards only their temperature. The
experiments on hybernants by artificial cold prove this fact, that
hybernation is attributable to other causes than to the reduction and
deprivation of nutriment; for the animals submitted to the ordeal
of cold were well [p301] fed, and in the lively season of advanced
spring. The deprivation of food seems to be a local consequence
provided for by the phenomenon of hybernation, and not its exciting
cause. Nor does there appear to be any change of organization in
these cases, but a state of constitution exists which we are unable
to account for further.
We have, in the next place, a series of experiments showing the
influence of the _seasons_ upon animal temperature with the
warm-blooded; by which it seems that they produce a variety of
results: and it is demonstrated that animals of warm blood in general
undergo some constitutional changes with the periodical returns of
the seasons. When, for example, the highest degree of temperature is
attained, animals no longer produce heat; so that their temperature
continues below that of the air in the hot season. And, in the cold
season, if the cold be not too rigorous, the animal’s age offers
a proportionate resistance to the cooling effects of the air as
the approach to maturity is attained. An elevated and a depressed
temperature thus produce contrary effects upon the internal powers
of generating animal heat, a high temperature arresting them, and a
low one promoting them. _Thus we cannot fail to observe the beautiful
adaptation of means to final causes_.
Upon the subject of _asphyxia_ in warm-blooded animals, Dr. Edwards
found a great dependence between animal heat and the faculty of
living without contact with the air, a state in which the blood is
not aërated by respiration, and which is sustained by hybernants
while in the dormant condition. Having submersed animals in water
of various temperatures successively, so as to bring them under the
influence of variable temperature, he found the _descending_ scale
of temperature the most hurtful. The _ascending_ heat was that which
prolonged life most. Between 20° and 10° the results were similar to
those between 20° and 40°.
Animals, then, of warm blood in a state of asphyxia hold their
existence on two principal conditions relative to heat; one regarding
the different measures by which some develope their heat, and the
other the degree of external temperature. The first is proper to
animals naturally, the second fortuitous.
Upon the _respiration_ of both young and adult animals the author
arrives at a conclusion opposite to that of common opinion, which is
founded on the notion of the heat in young animals being higher than
that of the matured. Finding, [p302] however, as already noticed,
that the parent exceeds the temperature of its offspring after
birth, it is naturally concluded that its consumption of air is also
greatest. This was experimentally confirmed, and is in unison with
other facts. In the first part of this work the vertebratæ of cold
blood were also found to consume least air in proportion to their
diminution of temperature. Temperature seems to act uniformly with
all the vertebratæ, and their consumption of air is in proportion.
The _mammiferæ_ have a lower temperature than _birds_, and they
consume less air than the latter. Fish and reptiles consume less air
than the warm-blooded, and possess a lower temperature.
The influence of the _seasons_ upon _respiration_ is considered
in the sixth chapter. Many changes occur in the atmosphere during
the revolutions of the seasons, varieties in the temperature, and
the pressure and density of the air. Dr. Edwards shows that the
faculty of producing heat with warm-blooded animals is greater in
_winter_ than in _summer_, the constitution of animals being adapted
to their individual climates; and in reference to the relation of
this faculty to the consumption of air, it is presumable, all other
circumstances being alike, that the consumption ought to be increased
with the faculty of developing heat, and the experiments justify the
presumption.
Upon the subject of _transpiration_, it is shown that the air not
only exercises a vivifying effect upon the constitution, but one
little less important in removing a vaporous substance from the
surface of the body, and which is separated from the fluids before
its conversion into vapour, and known by the name of perspiration
or sweat, which transpires from the skin. The variations in the
temperature of the air possess great influence over this function.
Experiments on this subject were detailed most fully in our last
Number, relative to cold-blooded animals; and therefore these need
not now be repeated in respect to the warm-blooded, for the results
are exactly similar, as to transpiration in equal and successive
periods, the comparative influence of dry and moist states of the
air, and the effects of air in motion and in repose. Inspection of
the table annexed to the work displays the similarity of the effects
produced by the same physical agents upon cold and warm blooded
animals, and this accordance serves to afford mutual support to the
different investigations.
We are now arrived at the fourth and last part of this [p303] work.
Much, however, of this part appertains to what has been already
detailed upon other animals. But the modifications of heat in the
human being, from the period of birth to maturity, will be found
highly interesting. They accord precisely with the results obtained
among the lower animals and mammiferæ; and present analogical proofs
of the general application of principles laid down in the preceding
portions of our notices.
While, however, we trace analogy throughout the animal kingdom, it
must be remembered that there are infinite sources of variation
arising from the extensive variety of species modifying those
principles, which are governed by a general harmony of effect. Of
all animals, man exhibits this variety the most, possessing, as
he does, attributes above all the groups of his class, from his
intellectual properties, speech, &c., rendering his race unique and
superior to all others. Our curiosity cannot, therefore, be allowed
to rest satisfied with the general application of principles,
until we have observed their modifications in the human being as
well as in brutes. It is highly interesting to inquire into the
conditions of human phenomena, and examine the forces which man
opposes in his intelligent character to the physical agents around
him. He is equally liable to their influence, exists by their
contact, and yields, like other members of the animal kingdom, to
their destructive tendency. The essential distinctions appertaining
to his economy are thus the more necessary to be understood. His
_organization_ affords him no shelter from the operations of physical
laws beyond that of brutes; but the superiority of his nature may
be supposed to modify their influence from causes referrible to his
_sensibility_. These have formed the subject of Dr. Edwards’s inquiry.
Man’s state and condition, at his birth, place him in very different
circumstances from those at which he subsequently arrives. Here,
therefore, we see an extensive field of inquiry; and it is suggested
whether, in the infantile state, man generates _less heat_ than in
more matured existence. Dr. Edwards has shown that the young of
mammiferæ generally, being born at the period when their eyes are
open, produce _less_ heat than adults. It is, therefore, presumable
that the generating powers of heat differ in the two states of
existence which man goes through, the infantile and mature.
But the power of producing heat differs among adult animals, and it
is desirable to know the limits of this faculty, [p304] Moreover,
this power differs in different parts of the body; so that, when
experiments are made, we should always apply the thermometer to
the same part of the body. Among twenty adult persons, Dr. Edwards
found the average temperature 36°.12: in infants from a few hours
to two days old, 34°.75 was the average. Thus we perceive that the
temperature of human infants is _inferior_ to that of adults. In
infants born previous to the usual period, two or three hours after
birth their heat was at 32° of Reaumur’s scale. So far we perceive a
similarity in man to the mammiferæ in general.
We have next a chapter on the effects of _cold_ upon mortality at
different ages. It is highly interesting to observe the care of
animals towards their offspring, in protecting them against the
effects of cold instinctively at a period before their own powers of
generating heat enable them to resist its baneful tendency.
Dr. Edwards endeavours to investigate the subject of cold, so as to
discover its limit of action. He examined the young of mammiferæ and
birds, the former born with closed eyes, and the latter unfledged.
He exposed them separately and apart to the air, so as to be
independent of each other’s warmth, and they exhibited a temperature
below their natural standard at the period of birth, even when a
degree of artificial heat was applied beyond that of adult birds.
The final result of these experiments was, that the application of
heat may be conducive to their developement, but is not indispensable
to their preservation. The author discovered, that the diminution
of temperature is not equally injurious at all ages. The _younger_
the animal, the _less_ is the injury sustained by cold, because the
faculty of producing heat is less powerful with the young than with
the matured animal, the power increasing as the animal grows, and
also with the increase of cold.
Still, however, this subject is open to inquiry, for the great
variety of species, and other circumstances belonging to the animal
creation, so modify the phenomena as to create an almost endless
field of investigation. When warm-blooded animals are exposed by
their parents to the atmospheric influence at an early age, they
are better provided against the perils of cold, being born with an
abundant source of heat. But, if the cold exceeds their powers of
generating heat, the mortality is so much readier. Hence arises
the danger of animals being born in the winter season. [p305] Two
circumstances are distinguishable, the refrigeration of the body,
and the temperature it is capable of sustaining. The cooling is so
much less injurious with the young. If two young animals of the same
species be cooled down equally, the youngest suffers the least. But,
in order to lower to the same number of degrees the temperature of
bodies of different ages, the external heat should be lowered in
proportion to the advancement of the animal towards maturity, in
order to compensate for the difference which the modification of age
produces.
While it is true that the younger animals suffer least from cold,
it is, at the same time, to be considered that they cool down more
rapidly. On this principle depends the mortality of our domestic
fowls and other animals, the management of which requires so much
observation and experience in order to rear them. In regions where
the temperature is liable to great alterations in the course of the
year, man and other vertebrated animals of warm blood are liable
to suffer in their health; for, though _cold_ should produce the
resistance derived from the necessary constitutional developement of
heat, this increase of caloric, having its limits, often exposes the
constitution to the effects of too great reduction of temperature, as
is exemplified in the frozen regions of the North Pole, in Siberia,
and in Russia.
The young of mammiferæ, in general, were found by Dr. Edwards to
differ very materially in the duration of their lives, in a state
of asphyxia, often being limited to from five to eleven minutes,
according to their developement at birth, the most advanced in
organization living the longest period. The author proved these facts
by placing animals in a state of asphyxia under water; and it is
remarkable that, in all his experiments, the _voluntary_ motions were
always first destroyed, the _involuntary_ outliving them. With dogs,
cats, and rabbits, sensibility existed only three or four minutes. A
puppy showed _automatic_ signs of life nearly half an hour. The best
divers appear to be able to remain under water from three to four
minutes.
When animals are entirely deprived of aërial contact, it may be
inquired, what are the principal functions exercised? When the air
circulates through the lungs, it imparts to the blood a peculiar
quality, by which its colour becomes changed. Deprived of this
influence from the air, the blood acquires a dark colour, and
the _nervous function_ is [p306] simultaneously affected. Among
_reptiles_, Dr. Edwards found that life could be maintained by this
dark blood; but it is questionable whether the circulation of venous
or dark blood can promote life in animals of the warm-blooded kind.
Temperature certainly modifies their capability of existence. Under
20°, they live longest; at 0°, their existence is shortest. The
vitality of the nervous system seems to be thus directly influenced
by temperature.
Of all the phenomena of animal life, those relative to the blood’s
state in asphyxia are, perhaps, the most interesting and curious,
from loss of consciousness, sensation, and voluntary motion attending
its disoxygenated state. If, however, animals differ so materially
under the influence of a deprivation of air, as to the duration of
such existence, we may imagine a corresponding difference relative to
their respirations modified by species, age, &c. Air, the _pabulum
vitæ_, is not equally consumed by all, but in different proportions;
at least, such is the presumption from the experiments upon animals
of warm blood. The relative proportions of this difference are sought
to be ascertained. Warm-blooded animals of equal size and age, at
their liveliest period of age, were the objects of comparative
inquiry. We must refer the reader to the table at the end of the
work for the results. A marked difference is observable between
the quantity of air consumed by the cold-blooded animals and that
required for the support of the warm-blooded; and each has an
organization appropriated to the individual distinctions. Thus the
structure of the reptile and fish entails the lesser consumption of
air, compared with that of the mammiferæ and birds. Fish consume
least air, reptiles stand next, then the mammiferæ, and, lastly,
birds consume most. The two last, however, very nearly approach
each other; so do also the two first; and the distinction between
the organization and the consumption of air is most strongly marked
between the fish and reptiles on the one hand, and the mammiferæ and
birds on the other, which, indeed, has caused their separation into
two distinct groups, by the appellation of _cold_ and _warm blooded
animals_,—a distinction which clearly separates the whole of the
vertebrated animals into two groups, bearing different physiological
characters in their relations to animal heat and respiration.
The mere temperature of the blood in each group is insufficient for
our knowledge of their distinctive characters. We [p307] further
find them characterised by a consumption of air in union with their
heat, so as to unite these two functions, and thus render them
dependent upon the same organs. Dr. Edwards has further shown, that
from birth to maturity the production of heat goes on increasing
with the consumption of air. And thus age (as well as the seasons)
has been shown to be a modifier of animal heat; for, as the hot
season advances, the consumption of air becomes diminished, and when
the cold sets in, it increases; and this decrease and increase are
accompanied by corresponding developements of heat.
In cases of fainting, of hysteric and asthmatic fits, the principle
here laid down, as to the balance between the air consumed and heat,
is instinctively acted upon by the most ignorant persons, who open
all the doors and windows to admit cold air, and dash cold water in
the patient’s face. The addition or continuance of heat increases the
affection. The application of cold produces instant relief. The state
of asphyxia is relieved, the senses return, the pulse beats at the
wrist, and the respiration goes on naturally. The _cooling_ renders
the air, unfit before, fitted for the purposes of life.
The effects of temperature upon the respiratory movements are
indicated also in those constitutional changes which diminish the
production of heat and the consumption of air. Organic affection
of the heart or lungs may produce this change, which entails the
necessity of a change of climate, or an alteration of temperature
artificially, to restore the balance between the air and the animal
heat.
A very elaborate and complete argument, and series of experiments,
are devoted to the subject of _transpiration_, and the effect upon it
of the influence derived from repose of the body and sleep, by the
air’s motion or stillness, and by the pressure of the atmosphere.
We have, however, pursued the interesting points touched upon
so far as to render it impossible to enter at present upon this
portion of the work. The importance of the subject demands a fuller
investigation and report than we have now room for; and we must,
therefore, defer it to another opportunity. [p308]
_Experiments on_ THOUGHT. By a Correspondent.
There is a very common prejudice respecting the rapidity of thought,
which is imagined by many to be almost unlimited: and the opinion
is very worthily illustrated by a reference to the oriental tale of
a man’s being bewitched into the belief that he had passed through
a period of seven years duration, and full of the most striking
vicissitudes; all in the time that he employed in dipping his head
in a pail of water. Now there is no doubt that we often dream of a
period of many years while we are only sleeping an hour; that is, we
dream of an impression of a long continued existence, or perhaps of
some detached fact scattered through such a period: but if any person
will write down all that he can possibly recollect, of the separate
imaginations that have passed through his mind in the dream, he will
find that he will be able to read them over with ease in less than
five minutes.
It is probable that there may be considerable diversity in the
rapidity of thought in different persons, as there is in that of
muscular motions: but there is no reason to think the diversity
greater. A healthy young man can run a mile in five minutes: a good
pedestrian in four; but no man ever ran a mile in three minutes;
and perhaps no horse in two. There is reason to think the rapidity
of thought does not differ more materially than this in different
individuals.
The rapidity of thought seems, however, more intimately connected
with that of muscular motion than by analogy only: for they appear in
some cases to be absolutely identical.
I have often been able to count ten in a second, in audible English
words; not distinctly, indeed, but so as to assure myself that I do
hear the ten words in their proper order; and to repeat the sounds
for several consecutive seconds. If I say the words _to myself_ only,
that is, if I think them over, I cannot repeat them ten times in less
than about nine seconds: I can never, for example, keep pace with my
pulse, though it sometimes beats as slowly as seventy in a minute:
nor can I, by any effort, think over the numbers from one to twenty
in two seconds.
If I say to myself the first lines of Milton or Virgil, or [p309]
Homer, or any other lines that may be still more familiar to me,
I cannot get through them much, if at all, more rapidly than I can
pronounce them, even when I fix my undivided attention on them.
The rapidity of sensation is also intimately connected with that
of memory and of muscular action. To cast the eye over a sentence,
attending to every letter, is an operation which is capable of equal
rapidity with the saying it over mentally: but it cannot be made much
more rapid. It required four seconds to look over a sentence which
occupied six in rapid reading.
The operations, which succeed each other with this limited rapidity,
are not incompatible with a partial attention to other subjects: just
as in running or walking, we may have our feelings very strongly
interested by the sight of surrounding objects without interrupting
the train of voluntary motions, which seems thus to be so linked
together in a continued chain, as to become almost involuntary. And
we may certainly be saying a thing over as rapidly as possible to
ourselves, and may at the same time be seeing, and hearing, and even
reasoning, so as to keep up what amounts very nearly, though not
completely, to a continuity of attention to several distinct trains
of ideas: in the same manner as the nerves of involuntary action
are notoriously employed in several distinct trains of concatenated
muscular motions and vascular actions, and as the ear of a musician
is able to follow and retain a dozen different melodies in harmony
with each other at the same time.
Dr. Darwin mentions an experiment which has a similar tendency to
show the close connexion between thought and sensation. He says, that
if we think intensely of a deep colour, for instance red, with the
eyes closed, we shall see a tinge when we open them of the opposite
colour, or green; just as if we had actually looked at a red colour
instead of thinking of it. But I confess that I have never been able
to satisfy myself completely of the success of the experiment.
These very hasty observations appear to me to be in great measure
original; and the results of such experiments are certainly more
calculated to illustrate the nature and powers of the human
mind, than the fanciful hypothesis of the fashionable [p310]
craniologists, with all their measurements of the heads of
murderers, are likely to become.
ZMINIS.
_London_, 20 _Oct._ 1827.
POSTSCRIPT.—I find that some similar remarks have been made by the
late Sir William Watson, in his Treatise on Time. He estimated,
from some experiments made in company with his friend Herschel, the
greatest possible velocity of sensation, such as to admit of about
three hundred distinct impressions on the eye or the ear in a second.
“It is true,” he observes, “that whoever attends to what passes
in his imagination on particular occasions, will be struck at the
apparent rapidity with which ideas appear to flow at times, and will
be apt to suspect them far to exceed sensation in that respect. But
it is probable that we are ourselves deceived in such cases.” P. 38.
But there are no direct experiments to prove this opinion. On the
other hand, a sound may be continuous, and yet consist of only about
twenty vibrations, or still fewer, in a second.
HIEROGLYPHICAL _Fragments, illustrative of Inscriptions preserved
in the_ BRITISH MUSEUM, _with some remarks on_ Mr. CHAMPOLLION’s
_opinions_. In _a Letter to the Cavaliere_ SAN QUINTINO. By a
Correspondent.
My dear Sir,
You will be glad to hear that I have made some little progress in
study of the Enchorial inscriptions which I had lately the pleasure
of showing you: my steps have, as usual, been guided by no _system_
whatever: they have been wholly _empirical_, and though very slow, I
trust they are so much the more sure: and I hope they will at least
serve as an excuse for my reminding you of the expectations you
kindly allowed me to entertain, that you would send me copies of any
thing of the kind that you might find among the objects entrusted
to your care at Turin. What I have lately done has only been to
ascertain the dates of many of the tablets sent by Mr. Salt [p311]
from Sacchara, all of them about the time of the last Cleopatra:
to identify the Enchorial name of Ptolemy DIONYSUS, and to make
out a passage relating to a donation of MUCH GOLD AND SILVER AND
GEMS TO THE SANCTUARY OF THE GREAT GOD AT MEMPHIS. The different
forms of the characters employed by the writers, in the same words,
constitute also a valuable addition to be means of deciphering any
new inscriptions of a similar nature, and I have already incorporated
many of them with my little Enchorial Dictionary.
The 48th and 49th plates of the Hieroglyphics, already published,
contain two tablets, apparently funerary, but without any dates of
the reigns: the ages of the persons seem to be expressed in the
hieroglyphical lines. In the 49th we find the name Berenice twice in
the Enchorial letters, and once in hieroglyphics; followed here by
Arsinoe, possibly as her mother.
This tablet, coarse as it is, abundantly shows that Horapollo and
Champollion are both correct, independently, as it seems, of each
other, in considering the rings, or cartouches, as chiefly confined
to the names of royal personages; and that I inferred the contrary
somewhat too hastily, from observing that the _imitations_ of those
rings were attached in the Enchorial inscription of Rosetta, to
several names not royal, and from having found such rings in other
hieroglyphical inscriptions, without the usual epithets of kings.
I had, indeed, remarked, that a “mysterious” name was _sometimes_
observable in the manuscripts without a ring, and I had pointed out
the same group as _a_ name in Lord Mountnorris’s manuscript, which
Mr. Champollion considers as the true name: but I am perfectly ready
to admit that Mr. Champollion has materially _improved_ on this hint,
as he has on many others.
The same line of hieroglyphics, however, contributes to add to my
reluctance in admitting Mr. Champollion’s reading of P.T.H; a group
which I considered as very probably representing these letters
long before the date of his publications; though I had only fully
identified the two first characters; it seems to me to agree better
with PETEH than with PHTAH; and I am inclined to think it was the
beginning of the names Petosiris, Peteharpocrates, and other similiar
words, [p312] as it is here annexed to the names of two or three
other deities. But I am by no means confident on the subject; and
beg only to be allowed a few years more to collect further evidence,
without being accused of _resisting_ conviction.
I must also claim a similar indulgence for my opinion respecting
the bird and the disc; which is so constantly found between two
names, that I could not avoid supposing it to mean simply _son_; I
confess that the arguments which Mr. Champollion has drawn from the
application of this character to some of the Roman names, as well as
those which Mr. Salt has deduced from the inscriptions which he has
published, are at least sufficient to silence me; I had, indeed, long
before observed that the first name of one pair of rings scarcely
ever found as the second of another, though I fancied the Minervean
obelisk might afford an exception. On the other hand, I cannot
explain, upon Mr. Champollion’s theory, the order of the names in
the tablet of Abydus, which might be supposed to have been purposely
intended to perpetuate this discussion.
It is admitted that this tablet contains the names of a chronological
series of kings, each characterized by one ring, containing what I
have always considered as the true names of the persons in question.
It is easy to grant to him that they are the praenomens only; as is
common in all modern chronology. But how comes it that there is one
exception to this, and that the reigning monarch is characterized
by his second name only, where he first occurs, and where we should
expect to find his father? This is precisely what would have been
required if the document had been forged to support my opinion;
though I should certainly have been very ungrateful for an argument,
which is more calculated to increase the difficulty than to remove it.
An objection of a similar nature may be deduced from the tablet found
between the legs of the sphinx, and copied by Mr. Salt, H. 80. The
“Mesphres son of Thuthmosis” of the Article Egypt is represented
naturally enough as doing homage to his deified father, under the
form of an Androsphinx; had he been doing homage to himself, the
names would scarcely have been so divided. They also occur repeatedly
afterwards in the inscription, but never together. [p313]
The tablet represented in Plate 51, is remarkable for the
confirmation which its date affords of the accuracy of our chronology
of the Ptolemies. It has no _pure_ hieroglyphics. It begins
immediately with “_The year 19, otherwise 4, of Cleopatra [Neotera],
and Ptolemy surnamed Caesar_: that is, the year 34 B. C.; and the
same date is repeated in a form somewhat more distinct, four times,
in the 10th, 11th, 12th, and 15th lines. In the last it is followed
by _the Queen gave to the Priests and High Priests_ . . then _Ptolemy
[Auletes?] . . Queen Cleopatra and King Ptolemy surnamed Caesar_.
It has before been observed, that the word _surnamed_, as it occurs
in these tablets, and in Mr. Grey’s manuscripts, comprehends the
characters which answer to the NEO of Mr. Champollion’s NEOCAESARIS.
The beginning of the group occurs elsewhere in the sense of _called_,
and can scarcely be read “ETO,” whether we consider the sacred or
the enchorial characters; nor do we find any thing nearer to this in
Coptic than ETE, meaning “_that is_,” while the characters are more
like TENE. Such are the uncertainties which continually beset us in
the application of the best established alphabetical characters even
to words of which we know the sounds: to investigate the unknown by
them is at present almost hopeless.
There are two tablets, from the caverns at Sacchara, about to appear
in Plates 70 to 74 of the Hieroglyphics, which Mr. Salt sent over
with particular interest, as being likely to contain some useful
materials for the comparison of the different kinds of characters
with each other. In this point of view, however, his well-directed
zeal has failed of its object: for the sacred characters relate
almost entirely to the gods and priests of the temple, while the
enchorial inscriptions below them contain dates and records of the
successive donations made to those temples. And this seems to be
equally true of the generality of double inscriptions, which are
scarcely ever identical in this sense, although they may greatly tend
to illustrate each other.
The first in order of these tablets (H 70, 71, 74 A) was marked
number 50 by Mr. Salt; it has seven stars at the edge of the wings
overshadowing the figures. It is first dated very distinctly _In the
year 6 of Cleopatra_; which ought to have [p314] been 6 _otherwise_
2; but the second date was perhaps omitted after an interval of more
than 20 years, which must have elapsed at the time of putting up the
tablet, as the subsequent dates demonstrate. The queen seems to be
styled _Isis_, but the name of the “younger goddess,” which is found
on her medals, does not appear in these inscriptions. In the 4th line
the word _Memphis_ occurs, though less distinctly than elsewhere.
It seems to be formed of characters meaning _Temple_, and _Good_,
and might naturally be read PHE-NUF; which agrees sufficiently well
with the NOPH of Jeremiah, translated Memphis by the Septuagint, as
well as with the Coptic PANUF, said to have been _Momemphis_. It is
possible that Phthah may have been meant by the Good god, NUF; but
there is here no character at all resembling the Enchorial name of
Phthah, which approaches to that of a figure of 4.
We next find a notice of the change of dynasty (Line 5) . . year
7: the _Gods Phre and “Horus” and Phthah? gave the victory to_
AUTOCRATOR CAESARIS _the Munificent_. The number 7 is indistinct;
if correct it must belong to the later of the double dates of
Cleopatra’s reign, which terminated the 22nd or 7th, the year of
the Battle of Actium, in which the _victory_ was obtained by the
_Emperor_ Augustus _Caesar_. Then follows a date of the _year_ 6,
probably of Caesar: and the seven stars of the wings may possibly
relate to the erection of the tablet in the subsequent year. We have
also a donation of _gold and silver gems_.
The second tablet (H 72, 73, 74 B) has first the date of the _year
19 of King Ptolemy_ [Auletes] the _Defender of the sacred rites_ (L.
3) . . _The year 4 of Cleopatra ‘Neotera?_ (4) . . _many years_ . .
(5) The year 7? _the gods ‘Phre and Horus and Phthah? gave the
victory to the Emperor Caesar_, ‘and Phthah and Horus who loved him
gave the dominion all men to? _Caesar_. (6) . . _gold and gems and
silver in abundance, gave them to the sanctuary of the great god in
the temple of Memphis_ . . The year 7 of Caesar: ‘Mechir 18? gave
to the sanctuary of the great god in . . (8) . . _gold and gems and
silver_ . . (9) _Memphis_.
We have here no subsequent year 19 to which the stars of the margin
can refer: and it seems therefore most natural to [p315] suppose
that they belong to the earliest date, with which the tablet
commences: and perhaps the seven stars of the former may have been
marked by mistake for six. The interpretation of the marginal stars
will be easily brought to the test of future observations.
Plates 75 and 76 contain portions of a large tablet from Sacchara,
very fairly written on chalk, of which the upper part is broken off,
leaving only a few traces of a hieroglyphic inscription, which seems
to have contained a date at the end, perhaps the 12th of Mechir.
(1) [In the . . year of Queen Cleopatra] and _Ptolemy surnamed
Caesaris_; the divine king . . living for ever. (7) . . _The year_ 9,
Athyr or Mechir 9, _of the great King Ptolemy_ the god ‘Brother of
Apis? DIONYSUS ‘the awful? living for ever . . (19) . . _the great
King_ Ptolemy the god ‘Brother of Horus? DIONYSUS . . . mighty as the
sun? . . . (20) . . . living for ever . . (21) In the year 7 Mechir
the 14 . . _The Queen Soter and King Ptolemy surnamed Caesaris_
living for ever . . gave . . (25) . . children, for ever. (28) . .
‘Written and engraved by? . . .
In the 79th plate there are four enchorial lines very distinctly
written, and beginning with a date, which must be either 24 or 28,
and most probably the latter, as there are 28 stars in the margin:
perhaps the 11th of the month, in the reign of _Ptolemy the son of
Ptolemy, may he live for ever_. The rest is not intelligible.
* * * * *
In this manner, my dear Sir, I have been creeping, while others have
been flying, though perhaps a little too near the sun. Possibly my
friend Champollion, and _your friend_ Seyffarth, would be able to
decipher much more of these inscriptions; and it is probable that
their versions might differ in almost every particular. In this
case it is unnecessary for me to say which of the two explanations
I should be inclined to prefer: for it is impossible to deny to
Champollion the merit of great industry, and deep, as well as
extensive research. I object only to his precipitation, and his
love of system, which, I think, cause him to be led away by his own
ingenuity, through a series of conclusions unsupported by sufficient
evidence. [p316]
As an instance of a hasty and undemonstrated assertion, I shall
mention his explanation of the group of characters which he considers
(Système, p. 82) as “forming the third person plural of the future
in all the verbs of the last nine lines of the hieroglyphical text
of Rosetta, expressing the different dispositions of the decree, and
answering to Greek verbs, which are always in the infinitive,” and
which he naturally enough reads SNE.
There is nothing absolutely incorrect in this statement, but the
reader naturally infers from it that the group in question occurs
either exclusively or principally in these nine lines. The fact is,
however, that in the first five lines, or rather half lines, the
group is found ten times, and in the remaining nine, only eighteen,
that is, about half as frequently, in proportion to the actual length
of the lines: nor can I find any where a context that favours Mr.
Champollion’s interpretation; though I have lately observed that an
Enchorial group, resembling ´O, is found almost uniformly to answer
to the Greek infinitive: being read perhaps MNR or MARE: but I
cannot make these characters agree either with the hieroglyphics in
question, or with the sounds SNE, which Mr. Champollion attributes to
them.
So little is Mr. Champollion in the habit of distinguishing _proofs_
from _assertions_ in his own case, that it is the less surprising
that he should sometimes confound them with respect to others.
He says, for example, with respect to the nature of the Hieratic
characters, which he explained to the Academy of Belles Lettres
in 1821, “_je me suis convaincu depuis que M. le Dr. Young avait
publié avant moi ce même résultat, et de plus, que nous avions été_
PREVENUS _de quelques années, l’un et l’autre, quant au_ principe de
cette découverte et sa définition, par M. Tychsen de Goettingue.”
(p. 20.) Professor Tychsen had _asserted_ this agreement as a
probable opinion: it was amply _demonstrated_ in 1816; _five years_
afterwards Mr. Champollion thinks he has a right to consider himself
as a new inventor of the doctrine, because he chose to neglect what
was done in a neighbouring country, and to undervalue the actual
_proof_, in which he had been anticipated, by classing it with a bare
_assertion_ to be found in a German publication. [p317] Precisely
in the same spirit he remarks, in the next page, that Barthélemy
and Zoëga had _pointed_ out the rings as containing proper names:
they had, indeed, _said_ that they might be proper names, _or_ moral
sentences, _or_ something else; but the only question was, if it
was worth questioning at all, to whom belonged the priority of the
_demonstration_ that they actually were proper names: which, before
the publication of the Archaeologia for 1814, was no where to be
found. This publication was the first great step after the discovery
of the pillar of Rosetta: the second was the identification of the
different kinds of characters, in 1816, by means of the Déscription
de l’Egypte: the third, the application of that identification to the
names of Ptolemy and Berenice: the fourth, perhaps, was Mr. Bankes’s
discovery in Egypt, of the name of Cleopatra, which he sent to Paris:
and on these grounds is certainly _founded_ ALL that is at present
known of Egyptian literature, for a very considerable proportion of
which we are unquestionably indebted to Mr. Champollion.
* * * * *
The French translator of Mr. Browne’s ingenious articles which
appeared in the Edinburgh Review, has certainly gone a good deal out
of his way to find matter of accusation against Mr. Champollion.
He quotes the text of a memoir published in 1821, and afterwards
_suppressed_, in order to show that Mr. Champollion then continued
to believe that the hieroglyphics were signs of things and not of
sounds; and that he disagreed with those learned persons who had
considered the hieratic writing as alphabetical. The date of this
suppressed paper is indeed of some consequence, as determining the
period at which Mr. Champollion made his rediscovery of what Dr.
Young had published in 1816; that is, the fact of the essential
identity of the two systems of writing. But the translator might
have found in the beginning of the letter to Mr. Dacier, dated in
1822, the same opinion respecting these systems of writing; that is,
the _hieratic_ and _demotic_, which, he says, are not alphabetic,
but “_ideographic_, like the hieroglyphics themselves,” expressing
ideas and not sounds: and he adds, that _he_ (!) has deduced from the
demotic inscription of Rosetta a series of characters which have a
“_syllabico-alphabetic_ [p318] value,” by which foreign proper names
were expressed. (p. 2.)
Nothing can possibly agree better than this with the opinions which
Dr. Young had long before published; and which he has since confirmed
in his octavo volume; and if Mr. Champollion’s ideas upon this
subject have sometimes appeared to fluctuate, it has probably been
more from a love of system, and a wish to establish originality, than
from any new discoveries that he can have made respecting these two
modes of writing in particular.
What precise forms of characters may be supposed to answer to the
sense in which Mr. Champollion employs the word demotic, cannot
very easily be ascertained. It is remarkable that his “SNE” is a
group very commonly found in the manuscripts of the Déscription de
l’Egypte, which Mr. Champollion might possibly call demotic; while it
cannot be identified in the Enchorial Inscription of Rosetta. This
is an instance of the difficulty of finding appropriate terms where
we have not exact definitions. The difficulty is not avoided by the
use of the word Enchorial, except that it may with perfect safety be
applied to such inscriptions as are capable of having any of their
words identified with the inscription so called on the pillar itself.
The verification of the chronology of Manetho must naturally be a
work of time, even after the complete identification of the names of
the kings, which cannot _yet_ be admitted to be satisfactory. There
is one discordance that it may be right slightly to point out, as
it is presented by Plate 43 of the Hieroglyphics: we there find the
29th year of the Sesenchosis of Manetho; and Manetho allots but 21
years to this king, who was the first of his dynasty, and could not,
therefore, like Philadelphus, have continued any era from an earlier
period.
It is easy to observe, in comparing Mr. Cailliaud’s copy of the
Tablet of Abydus, as published by Mr. Champollion, with those of our
countrymen, Mr. Bankes and Mr. Wilkinson, contained in the 47th plate
of the Hieroglyphics, or with the manuscript copy of Mr. Burton, how
much more hastily the French traveller had executed his task than
_any one_ of the three Englishmen. [p319]
Another of Mr. Wilkinson’s very valuable inscriptions, from a temple
at Kous, must be allowed to give evidence much more favourable to Mr.
Champollion, as far as it regards the signification of the _plough_,
which seems to enter into the composition of _Philometor_, as applied
to Cleopatra and “Ptolemy Alexander,” who are called Philometores
Soteres, both here and in Anastasy’s Greek Manuscript. The name of
Alexander had never occurred to the author of the article EGYPT, but
he had evidently a foresight in what way it would make its appearance
when he observed, N. 55, “it will appear hereafter, that a knowledge
of the enchorial forms may possibly contribute very materially, at
some future time, to assist us in determining it:” and he immediately
proceeds to the subject of PHONETIC HIEROGLYPHICS.
The plough seems to be exchanged on the Minervean obelisk for the
dentated quadrant and chain, which may hence have been synonymous
with the dentated parallelogram or comb: both perhaps having
represented instruments which bore the same name, and served the same
purposes, though of different forms: they may, for instance, have
been rakes or harrows, and may hence have borne some analogy to the
plough or hoe. Whether they had names beginning with M, may still be
questionable.
Mr. Champollion has endeavoured to explain the absence of the names
of our queens from the tablet of Abydus, by saying that it must be
considered as a tablet “purely _genealogical_.” First Letter to the
D. de B. p. 89. A reader is naturally disposed to acquiesce in this
explanation, since Mr. Champollion, who has carefully examined it,
asserts it on his own credit; especially as the assertion appears to
be supported by a long and minute discussion. Unhappily, however,
it is only necessary to compare his brother’s chronology in P. 107,
with his own Plates II. and III. fig. 5, from which it appears
that Amenses, who _reigned_ more than 20 years, was the mother
of Thuthmosis the second, whose name is in the tablet, while his
mother’s is _omitted_. It is true that, with his usual ingenuity, Mr.
Champollion seems afterwards to change his ground in the same page:
for he says, that one only of two brothers or sisters was inserted,
in order to keep the number of the [p320] _generations_ unaltered:
and he might have added that Amenses was the sister of Amenophis,
whom she succeeded. If he had stated this clearly, the reader might
have judged for himself, whether such a coincidence was or was not
sufficient to support the chronology of Manetho; which was, however,
by no means in want of _such_ support: in the article EGYPT, for
example, Manetho’s chronology of this dynasty is fully adopted: and
the same ‘cartouche’ is read _Thuthmosis_, which Mr. Champollion,
after all his parade, still admits to be Thuthmosis: nor is there
a difference of half a century in the dates assigned to his reign
by various chronologists. It was established in the article Egypt,
that the name contained that of Thoth, the Egyptian Hermes, and for
this reason it was considered as better established than any other
of the names of the Pharaohs. Mr. Champollion had never discovered
this for many years afterwards: and yet we have been told by an
ENGLISHMAN in the last Quarterly Journal, that to Mr. Champollion the
_greater part_ of the _discoveries_ made by the interpretation of
hieroglyphics are owing!
Believe me, dear Sir, very sincerely, yours,
* * * *
_London_, 24 _Nov._ 1827.
_On the Naturalization of Fish. By_ J. Mac Culloch, M.D., F.R.S., &c.
Dear Sir,
As I promised you that I would communicate to you, from time to
time, any new remarks or facts which might occur on the subject
of naturalizing sea-fish in fresh water, I am pleased to have an
opportunity of noticing a few circumstances which may serve to keep
alive in the public mind a subject, from which I cannot yet help
foreboding useful results, in spite of the neglect and opposition
which it has experienced from every person, I believe I may safely
say, to whom it has been proposed, except Mr. Arnold. I am perfectly
safe in saying, that, with this sole exception, every individual to
whom the facts have been described, and the experiment proposed, have
replied by doubts, or cavils, or objections of some kind; many, by
[p321] positive disbelief of the very facts; while the far greater
number have been persons, whose entire ignorance of every requisite
point of physiology, natural history, and chemistry, must, of course,
have rendered their objections sufficiently unworthy of notice,
though not sufficient to restrain the confidence with which they
have been urged. The satirical writers of the day view this as the
character of the age: the more obvious aspect which this disposition
presents, is the feeling, as if he who attempted, by suggesting an
improvement, to render a service, was meditating an injury, and was
an enemy to be opposed at all hazards. I must permit you to settle
metaphysical and moral questions so profound as to exceed my own
ingenuity.
But I cannot avoid regretting that Mr. Arnold is not the rich
and idle proprietor of some of the tens of thousands of acres
of fresh water, whether Scotch or English, in which a ‘sea-fish
cannot possibly live,’ or ‘would certainly not be eatable’: and,
in addition, that, instead of a not very opulent and very busied
‘notary public,’ he was not in possession of some five thousand of
these acres, with as much money, and as much leisure. And I feel
bound to add to this apology for what he _has not_ yet done, that
the expense of such a course of experiments is considerable; at
least in this comparison. A superintendent would be necessary; and
for the purpose of taking and transporting the fish, still more of
drawing nets periodically and frequently, to ascertain the progress
of the transplanted fish, there must be expensive assistance, for
which, as yet, there can be no returns; while that, in addition
to irregularities and rocks in the pond itself, impeding the
accurate drawing and examination, must also be the apology for the
imperfection of the present additional report as to the success for
certain fishes. It is plain that, though ten or a hundred turbots
were present in a pond of four or five acres, the fact is not one
that can easily be ascertained. Let those who have money, leisure,
and water, and nothing else towards the investigation of this object,
restrain, at least, _their_ incredulity and opposition; as may also
they, very safely, who never saw a fish, except on the stall of a
London fishmonger.
With respect now to some facts: it had been said that the water was
salt, because this pond was situated at a sea [p322] embankment.
I stated before, that it admitted the sea, by leakage, in summer,
when there was little comparative supply of fresh water, and was
therefore brackish, or saline. I have since ascertained the exact
proportion of salt in the water, at those times when the fresh
water is least. In the driest and hottest part of one summer, the
proportion of salt in it, as compared to the sea without, was as 40
to 150. In another, peculiarly dry, 1827, it was one half; and the
water, having then been at the lowest, it cannot ever be computed to
exceed this. Moreover, this period of saltness cannot easily, even
in such a summer, occupy more than the months of June, July, August,
and September; or, more strictly speaking, it is probable, scarcely
one half of that time in general, in so rainy a climate; a climate
equalling Penzance in the quantity of rain.
In winter, that is, during five or six months, or less, if any
objector pleases, it is fresh. That cattle drink it freely, is not
an exact chemical proof; but I must admit, that I have not analyzed
the water at that period, holding the objection in great contempt.
It may be sufficient to say, that it then occupies a space of about
sixteen acres, or increases to this magnitude from four and a half
acres; so that it cannot, at least, be very salt, while the fish, and
the mullet in particular, are found in the remotest ditches, among
the meadows. But, in defect of an analysis, which I have not had the
means of making, there is a valid reason why the water should be
fresh when the size of the pond is much extended. The presence of
sea-water in it, is, in all cases, the consequence of a depression
of the water within the sea-wall, which allows of leakage or
infiltration at the upper part, so as, in high tides, to equalize, as
far can be done in the short period of high water, the levels within
and without. This, it is plain, must cease whenever the water within
is higher than the sea without; and hence it is that there can be no
access for the salt water in the winter or rainy months.
Enough of the mere fact: the objections derived from which ought
not to demand an answer among physiologists; while to those who
argue physiological points in utter ignorance of all that belongs
to physiology, it is probable that all answer is fruitless. It was
stated before—the question is simply twofold; [p323] respiration
and food. If fish can breathe indifferently salt water or fresh,
for one week or one month, and if, in their new element, translated
from salt to fresh, they thrive or grow, fatten and breed, the trial
of three weeks or three months is a sufficient proof that they will
neither sicken nor die of fresh water. If they can find food, it is
indifferent whether the medium is fresh or salt. It is the misfortune
of the age to understand every thing without knowing its principles;
just as every man is now a physician. A few, more profound, who
chance to know that salmon divide their time between fresh and salt
water, possess other reasons, and find other objections; which they
must be permitted to explain for themselves. I ought not, while on
this particular subject, to omit one fact, which has come to my
knowledge since the former papers were written, on the voluntary
emigration of a fish, supposed to be peculiarly delicate and
peculiarly attached to the sea, into fresh water. This is, that,
in Virginia, the herring ascends the rivers, even up into the most
minute communicating branches, and as far as it can reach; while a
somewhat recent traveller describes them as being so abundant, that
it is impossible to cross the fords on horseback during the season
of their migration, without destroying them by the horse’s feet. To
proceed to the _historical_ condition of this pond.
I have already stated the difficulties arising from want of leisure
and wealth in the proprietor, added to non-residence I should say,
whence chiefly has arisen the difficulty of tracing the results. Let
those try for themselves, who consider that all this might have been
ascertained in a twelvemonth, and with the same means. Since the
communications I formerly made, the Pilchard has been introduced. It
swam away briskly, therefore it would not die of the fresh water;
but it has not been retaken. The retaking of individual fish, to
ascertain their presence, is a fundamental difficulty, as I before
pointed out.
The Brill has also been introduced since my former list. It has been
retaken; and, within one year, had grown to double the original size.
The Turbot. Fifty or sixty were introduced, averaging about eight
inches in length. Some were retaken in a year, for the purpose of
examination merely, like the former and most others; [p324] they
also had grown to double the size. There is no prospect of dying
in these cases, it is abundantly plain; that they will breed is
probable, but there has been no time, nor would the young have been
taken. What is to prevent healthy fishes from breeding? The young,
indeed, may be eaten; if so, it is for want of room, or want of a
proper balance in this mixed population. No one knows any thing,
either of the ordinary growth, propagation, or destruction of fishes;
and how then can any one decide on what is regular or extraordinary?
The Wrasse has been retaken after a considerable period; therefore it
is not dead.
The Basse has propagated; and so has the Brill.
The Red Mullet has been introduced, and is living.
The Whiting was introduced, and taken in good health many weeks
after, but not since.
The Grey Loach is thought to have bred considerably.
The Atherine continues to breed.
I formerly mentioned that the flavour of the several fishes was
improved: this is now more positively asserted, in addition, of the
Basse, the Plaice, and the Red Loach. Others were mentioned in former
communications.
Loss of property, or flavour, has been made a speculative objection
by the unvarying objectors. General experience has shown, that in all
fishes, as far as known, the access to fresh water, or fresh water
food, improved the flavour; in many, in oysters, muscles, cockles,
shrimps, it is vulgarly notorious; as in mere sea water they are
worthless.
There is a popular objection, on this head, made by the country
gentlemen, which I must answer; to those who _think_ about what they
know, it would have been superfluous. The salmon is good when it
comes from the sea, and bad when it is returning. Doubtless, it is;
while the reason ought to be plain, even to an angler. It is in full
health in the first case: in the latter, it has spawned; and, at that
period, every fish is proportionally as bad as the salmon; many are a
great deal worse. The fault is not in the water, nor probably in the
food; it is in the spawning, and with any food the same effect takes
place, in all fishes, everywhere.
I suggested in former communications, that an essential point [p325]
to ascertain, in any view of economy, or management, would be the
proper balance of species; to discover what kinds would so live
together that all the species might find food; might breed, each to
its useful limits, so as to be serviceable to ourselves, the keepers
or the flocks, and without hazard of the extermination of any kind. I
may illustrate what is here meant, by a simple fact, in the ordinary
economy of fresh water fishes in confinement. Pike and perch can live
together, because the natural defences of the perch prevent the pike
from exterminating the race, voracious as the enemy is. If trout and
pike were confined in a narrow water, the trout would be destroyed.
Or otherwise, it must be our object to ascertain, in an economical
view, how to feed, by means of species that we do not desire to eat,
those which we do cultivate for our own uses. This is a difficult
question, which can only be overcome by time and experience; by
knowledge; by knowledge, when we are in a state of entire ignorance;
ignorance of every thing that relates to fishes, as great as if they
were the inhabitants of another planet. This was one great source of
difficulties with us in this case; and I, myself, must plead guilty,
I fear, to a general recommendation of introducing every fish as a
mere matter of trial; the result of which has been mischievous. The
basse appears to have been the great enemy; to have eaten up the
greater number of many species, and given no return. It has proved
the pike of this pond. This could not have been foreseen; it is a
caution for future speculators. Others will be discovered in the
course of trial. It appears also that the common crab has proved
destructive, probably by eating the spawn of larger fishes. From some
enemy or other, the eels, which at first abounded to an incredible
degree, have most materially diminished, and so have the shrimps.
The latter, at least, appear to have been destroyed by the basse.
Time and trial will teach us what to do in this case; in the infancy
of ignorance, man might have supposed that he could keep wolves and
sheep in one field, and have constructed a pen for foxes and fowls,
rabbits and weasels. We must not accuse nature of our own ignorance.
The question is here a difficult one; but a little more study [p326]
of the general habits of fishes, merely as we know them already,
and even of their anatomy, will go far to lay the foundation of
useful rules on this head, even without a hazardous trial, which may
ultimately not become in our power to remedy, as I much fear may
prove the case with respect to these unlucky basse. Not to enter on
this further than as it may serve for a general illustration of what
is here meant, the anatomy of the mullet proves that it lives on
worms; on the lumbricus marinus, and others; and so do its habits.
So also may the very food of others, as found in the stomach, serve
to indicate their natural or ordinary food. Reversely, the anatomy
of a cod’s jaws, and its stomach also, prove it to be omnivorous,
omnivoracious. Or, further, the anatomical character of the diodon
proves that it eats shell-fish; as we are equally able to limit the
range of food in the flat-fish which have no air-bladders, and cannot
quit the ground.
But in this brief communication, I must not enter further into this
subject than is necessary for mere illustration. I may take some
further opportunity to point out the probabilities, as to mutual food
and protection, in any artificial cultivation of this nature, as they
might be derived from studying the little that we do know about the
structure and habits of fishes. All that I need add here, is, that I
have suggested the introduction of limpets, periwinkles, and cockles;
as affording food without furnishing enemies: a matter which had
been overlooked. To exterminate the enemies which have been unwarily
introduced, will not prove so easy a task; unless, at least, we could
find their natural enemies; find the great secret by which alone, in
all cases, man can make war on those whom neither his artillery, his
physic, nor his politics can reach.
The transportation of fishes has been objected to as difficult.
I had occasion to make some remarks on this formerly, and on the
vitality of some kinds. The difficulty is not so great as has been
imagined. The fact generally is, that fishermen, even down to the
very sentimentalists who worship the gentle Izaak, and who are
sometimes scarcely possessed of the wit of a fish, treat them as they
would a stone; as if they had not lives, and wills, and opinions,
and were not part of the same [p327] creation as ourselves; as if
that creation, which outnumbers ourselves by millions of millions
almost beyond algebra to express, was not, like ourselves, under His
care. They are easily killed by violence; they kill themselves by
over-exertion, from anatomical peculiarities; as every trout-fisher
knows; that is to say, the fact, not the cause. Let them be treated
with gentleness when taken, as if they could feel; and they will
not die in being removed into a cask of water. The flat fish are
all peculiarly tenacious of life, so are all those of firm muscles
generally: the vitality of the carp and of the minnow also is
notorious; and so it is as to many other kinds. All these can be
removed, and carried far, even in straw; but in truth, he who chooses
to make his experiments like a philosopher, and who desires to
succeed, will not fail.
Yet let me point out what I have suggested to Mr. Arnold, among
other things: to him, whose merit as an ardent experimenter, always
ready to adopt a reasonable suggestion, and never seeking for an
objection, ought to stamp his character as a genuine follower of the
true philosophy; the exception, in this particular case, to every one
else. This is, to adopt the Chinese method of transporting the spawn
of fishes; as affording a far greater facility to the introduction
of species. I presume that the general fact must be known to your
readers; though I believe that I ought to doubt: because I quoted
the same practice from Columella formerly, as in use among the most
ancient Romans, among the common farmers.
This substance is perpetually brought up by the trawl net, very
injuriously, as it relates to fisheries; and in many cases, the
fishermen contrive to guess tolerably well to what fish it belongs.
That it may be transported to any distance, the familiar practice
of China proves: since it is there a common article of sale in
the markets; while there also, I may incidentally remark, the
cultivation of fish for sale, their transportation to market, and
their replacement in the ponds, if unsold, is as much matter of
ordinary farming as the management of a poultry-yard; while the
pond is often the most profitable part of the farm. They also,
who do not already chance to know it, may be informed, that this
species of poultry-yard, or fish-pond, is as easily and regularly
[p328] stocked in this manner, and managed, as any other portion
of the farm: since it is even destroyed, or suffered to become dry
occasionally, and again renewed in the wet season, by the means of
purchased spawn, or stock; just as a sheep farmer buys lambs to stock
his mountains. If England is too wise to learn of Rome or China, or
of France and Germany, or even of the experiments on which I have
dwelt so much and so often, it must be a pleasing reflection that
it is already so amply informed as to have passed the bounds of
all possible improvement and all possible wishes. But that I may
terminate this particular suggestion, I will only further point out,
that lobsters, and the crab tribe generally, might very easily be
transported in this manner, and that, in them, it is easily known
when the _ovum_ has been impregnated, by means of a black spot with
which it is then marked.
If I ought to apologize already for the length of this communication,
I shall conclude it by saying, that whatever may be judged of the
general philosophy of this subject, there is not and never has been
any thing to prevent the cultivation of fish, in ponds of salt-water
at least, or the preservation of them in any water in which they will
live for a sufficient length of time, so as to render that a depôt
for the purposes of a fish store, calculated for the steady supply
of a market, in the manner which I formerly described and proposed.
If, after so many years as this proposal has been made, London has
not seen either the facility, or the utility, it will discover them
at some future day; just as it discovered, ten years after there had
been twenty-six steam-boats on the Clyde, that a steam-boat might
possibly be of use on the Thames; just as it opposed gas-lights, and
just as it has adopted gas-lights. [p329]
_Nugæ Chirurgicæ; or, a Biographical Miscellany, illustrative of a
Collection of Professional Portraits_. By W. Wadd, Esq., F.L.S. &c.
8vo. pp. 276. London, 1824 Longman and Co., and Callow and Wilson.
_Nugæ Canoræ; or Epitaphian Mementos (in Stone-cutter’s Verse) of
the Medici Family of Modern Times_. By Unus Quorum. London, 1827.
Callow and Wilson.
_Mems., Maxims, and Memoirs_. By W. Wadd, Esq., F.L.S.,
Surgeon-Extraordinary to the King, &c. 8vo. pp. 303. London, 1827.
Callow and Wilson.
We have placed these three Works together, because they are so
closely allied as to form a whole, and also because _Nugæ Canoræ_
and _Nugæ Chirurgicæ_ bear internal evidence of being written by
the same pen; and when we say further, that they are characterized
by good feeling and good humour, we are sure we are not far off in
our _guess_ about who is ‘UNUS QUORUM.’ These volumes come within
the scope of our Journal, as comprising an outline of the history
of medical science, sketched in a vein of pleasantry that makes it
no less agreeable to the general than to the professional reader,
and we have derived both amusement and information from its perusal.
Like the ‘Gold Headed Cane,’ it helps us to much curious modern
biographical anecdote, with the addition of varied entertainment for
the medical antiquary. While, however, we recommend these ‘Mems.,’
and commend the literary loungings of contemporary practitioners,
we cannot but regret the neglected volumes of Aikin and Walker, and
lament that the lack of feeling for the annals and literature of
their profession, should be less active in the medical public of this
country, than with our professional brethren on the Continent.
‘_Nugæ Chirurgicæ_’ is a _Catalogue Raisonnée_ of a scarce collection
of Medical Portraits. We believe only 250 copies were printed;
from which circumstance, and its recording the congregation of the
greatest assemblage of medical men ever met together, it is probable
that it may some day become a medical rarity. The author’s original
intention appears merely to have been to describe the portrait,
with some characteristic trait; but an after-thought seems to have
occurred, and in the “Memorabilia,” the “_Medici Family_” are, as it
were, retouched and varnished, so as to become [p330] very agreeable
pictures. We shall now present our readers with a few specimens of
this gallery, taken at random.
EURICUS CORDUS.
“Cordus, who was accustomed to receive his fees only at the
termination of patient’s disease, describes, in a facetious epigram,
the practitioner at three different times, in three different
characters.
Three faces wears the doctor; when first sought An angel’s—and a
god’s the cure half wrought: But when, that cure complete, he seeks
his fee, The devil looks then less terrible than he.
“The epigram of Cordus is illustrated by the following conversation,
which passed between Bovart and a French marquis, whom he had
attended during a long and severe indisposition. As he entered the
chamber on a certain occasion, he was thus addressed by his patient:
‘Good day to you, Mr. Bouvart; I feel quite in spirits, and think
my fever has left me.’ ‘I am sure of it,’ replied the doctor; ‘the
very first expression you used convinces me of it.’ ‘Pray explain
yourself.’ ‘Nothing more easy: in the first days of your illness,
when your life was in danger, I was your _dearest friend_; as
you began to get better, I was your _good Bouvart_; and now I am
Mr. Bouvart: depend upon it you are quite recovered.’ Bouvart’s
observation was grounded on a knowledge of human nature: every day’s
experience shows, that ‘_accipe dum dolet_’ should be the medical
man’s motto.
JOHN CASE.
“In one of the profound pieces of astrological bombast written
by this singular genius, he gives an account of the creation of
Adam: ‘_Thus_ Adam was created in that pleasant place _Paradise_,
about the year before Christ 4002, viz. on April 24, at twelve
o’clock, or midnight.’ His name was latinized to _Caseus_, which was
occasionally interpreted Dr. _Cheese_. Granger says the following
anecdote of Case was communicated to him by the Rev. Mr. Gosling,
in these terms: ‘Dr. Maundy, formerly of Canterbury, told me, that
in his travels abroad, some eminent physician, who had been in
England, gave him a token to spend at his return with Dr. Radcliffe
and Dr. Case. They fixed on an evening, and were very merry, when
Radcliffe thus began a health: ‘Here, brother Case, to all the fools
your patients.’ ‘I thank you, good brother,’ replied Case; ‘let me
have all the fools, and you are heartily welcome to the rest of the
practice.’’
THOMAS DAWSON.
“The following anecdote is related of him: After he became M.D. he
attended his neighbour Miss Corbett, of Hackney, who [p331] was
indisposed; and found her one day sitting solitary, piously and
pensively musing upon the Bible, when, _by some strange accident_,
his eyes were directed to the passage where Nathan says to David,
‘Thou art the Man.’ The doctor profited by the kind hint; and, after
a proper time allowed for drawing up articles of capitulation,
the lady, on 29th May, 1758, surrendered herself up to all his
prescriptions, and the doctor very speedily performed a perfect cure.
PHILIP HECQUET.
“‘C’est une erreur de penser que le sang soit nécessaire à la
conservation de la vie; on ne peut trop saigner un malade;’ are the
words put into the mouth of our doctor, in the character of Sangrado
by the facetious Le Sage. Hecquet, both in theory and practice,
carried the _anti-phlogistic_ system to a greater extent than any
other man, and defended the ‘_boisson_’ and the _bleeding_, saying,
‘J’ai pour garants de mon sentiment, sur le _Régime maigre_, les
médecins les plus fameux, tant anciens que modernes.’ He was a
conscientious practitioner of his own eccentric doctrines, and it
was perfectly consistent with his character, that ‘loin d’imputer la
mort du chanoine à la boisson et aux saignées, il sortit en disant,
d’un air froid, qu’on ne lui avait pas tiré _assez de sang_, ni fait
boire _assez d’eau chaude_.’
“The practice of _bleeding_ was carried to a singular extent in
France, and it was the fashion, at one time, to bleed on the
opposite side to the part affected; if the pain was on the right
side, they bled in the left arm, and _vice versâ_. Pierre Brissot
produced a civil war in the medical world by writing against the
custom, and, in the year 1600, was driven into exile, by edict of
the University of Paris, for thus opposing the established practice.
SIR CHARLES SCARBOROUGH
“Was a man of great versatility of talents; he wrote a ‘Treatise on
Trigonometry,’ and a ‘Compendium of Lilly’s Grammar;’ gave lectures
on mathematics at Cambridge, and on anatomy in London. His epitaph
records that he was
Inter Medicos Hippocrates, Inter Mathematicos Euclides.
He read the lecture founded by Dr. Caldwell, at Barber-surgeons’
Hall, for many years; where he was the first who attempted to
account for muscular strength and motion on geometrical principles.
He was a man of amiable manners and great vivacity of conversation.
Seeing the Duchess of Portsmouth eat to excess, he said to her, with
his usual frankness, ‘Madam, I will deal with you as a physician
should do; _you must eat less, use more exercise, take physic, or be
sick_.’
DR. PITCAIRN
“Was a great enemy to quackery and quacks, of whom he used [p332]
to say that there were not such liars in the world, except their
patients. A relation of his, one day, asking his opinion of a
certain work on fevers, he observed, ‘I do not like fever curers;
we _may guide_ a fever—we cannot _cure_ it. What would you think of
a pilot who attempted to quell a storm? Either position is equally
absurd. We must steer the ship as well as we can in a storm; and in
a fever we can only employ patience and judicious measures, to meet
the difficulties of the case.’”
Turn we now to the second article in our list,—_Nugæ Canoræ_; and we
are satisfied that our readers will agree with us in the correctness
of our _guess_. It is the production, at any rate, of one who has
lived much in the medical world, and no unobservant spectator of
the vices and virtues, the feelings and failings of contemporary
practitioners, possessing tact to “catch the manners living as they
rise.” In short, it is a pleasant _jeu d’esprit_; and we hail it as
an omen, that in these “piping times of peace,” the days of Garth,
Goldsmith, and Darwin may be revived, and that the medical fraternity
may again employ their _leisure_ hours in amusements for which their
education and intercourse with society so well qualify them.
After a humorous preface, in which the removal of the College
of Physicians to Pall-mall East is lamented, the work, for very
satisfactory reasons, is dedicated to the Presidents of the two
Colleges and to the Master of the Company of Apothecaries, for the
year 1927—and as a character in one of Foote’s farces wishes he were
to be born “fifty years hence,” so should we like to have a peep at
the “Clines and Coopers,” the “Halfords and Warrens,” of that day. We
wish, with the author, that they may be as distinguished ornaments of
their profession as those of our own.
That the old college should still be preserved for medical purposes,
it is proposed to turn it into a “Medical Mausoleum,” where the
“Medical Fraternity” are to be buried on the same terms as the
Parisians are at Père la Chaise—and then follow the supposed Epitaphs
of the present race of the “Medici.” Due honour is done to learning
and talents; while quackery, in all its ramifications, meets with
just castigation. The names of Heberden, Turton, and Baker are
noticed with the respect to which their virtues and acquirements
entitle them.
Passing from these, we are introduced to an eccentric of the old
school. [p333]
“SIR RICHARD JEBB, BART. M.D.
“Here, caught in Death’s web,
Lies the great Doctor JEBB,
Who got gold-dust just like Astley Cooper;
Did you speak about diet,
He would kick up a riot,
And swear like a madman or trooper.
“When he wanted your money,
Like sugar or honey,
Sir Richard looked happy and placid;
Having once touched the cash,
He was testy and rash,
And his honey was turned to an acid.
“Sir Richard was very rough and harsh in manner. He said to a
patient, to whom he had been very rude, ‘_Sir, it is my way_.’
‘Then,’ replied the patient, pointing to the door, ‘I beg you will
make _that your way_.’ Sir Richard was not very nice in his mode of
expression, and would frequently astonish a patient with a volley
of oaths. Nothing used to make him swear more than the eternal
question, ‘What may I eat?—Pray, Sir Richard, may I eat a muffin?’
‘Yes, Madam, the _best thing_ you can take.’ ‘O dear! I am glad of
that. But, Sir Richard, you told me the other day, that it was the
_worst_ thing I could eat!’ ‘What would be proper for me to eat
to-day?’ says another lady. ‘Boiled turnips.’ ‘Boiled turnips! you
forget, Sir Richard, I told you I could not bear boiled turnips.’
‘Then, Madam, you must have a d—— d vitiated appetite.’”
We cannot help bringing before our readers the following well-known
“characters” of their day, and should have indulged in more ample
quotations from these amusing “Epitaphs,” were we not afraid of the
imputation of “inappropriateness.”
“_On a most venerable and highly venerated Surgeon, lately deceased_.
‘Multis ille bonis flebilis occidit,
Nulli flebilior quam mihi.’—HOR.
“Of manners gentle, and in soul sincere,
Removed beyond this sublunary sphere,
Here lies an honest man!
Endued with caution, yet devoid of fear,
In practice dexterous, in judgment clear—
Excel him if you can!”
To this, we think, may be affixed the name of Henry Cline! [p334]
“CHARLES GOWER, M.D.
‘Discours de bons mots!’
“Ye sons of humour, of frolic, and fun,
This stone will inform you that Gower is gone.
Poor Gower! eccentric, facetious, and funny,
Lik’d nothing so well as other men’s money.
Alas! he is gone—’tis hard to say where,
The victim of mirth, imprudence, and care.
Where’er he is gone, his companions he’ll smoke,
For, cost what it will—he will have his joke.
“‘I knew him well, Horatio!’” exclaims our Author—“‘a fellow of
infinite jest!’—Chairman of the St. Alban’s Club, where oft ‘he
set the table on a roar.’—And who did not know this eccentric
oddity? Gower had considerable talents, but they were directed
every way but the right. He made medicine a plaything, never being
steady in professional pursuits. He wrote several singular books:
one he entitled ‘Auxiliaries to Medicine;’ another, ‘The Art of
Painting;’ both of which pourtray the character of their author. His
unsteadiness led him into difficulties, and he died in obscurity.”
“DALMAHOY.
‘Thrice happy were those golden days of old,
When dear as burgundy p’tisans were sold.’
“Dalmahoy sold infusions and lotions,
Decoctions, and gargles, and pills;
Electuaries, powders, and potions,
Spermaceti, salts, scammony, squills.
Horse-aloes, burnt alum, agaric,
Balm, benzoine, blood-stone, and dill;
Castor, camphor, and acid tartaric,
With _specifics_ for every ill.
But with all his specifics in store
Death on Dalmahoy one day did pop;
And although he had doctors a score,
Made poor Dalmahoy shut up his shop.”
“HENRY REVELL REYNOLDS, M.D.,
‘Os placidum moresque benigni.’
“Here well-dressed Revell Reynolds lies,
As great a beau as ever!
We may perhaps see one as wise,
But sure a smarter never.
“Dr. Reynolds may be considered as the link between the ancient and
modern costume of the Faculty: to the last, he wore a well-powdered
wig and a silk coat. He was an excellent [p335] specimen of a
well-dressed and well-bred gentleman. As a practitioner he ranked in
the first class, and he was one of the physicians who attended King
George the Third during his afflicting and protracted malady.”
“RICHARD GRINDALL, ESQ.
‘Eamus quo ducet gula.’
“Within this place Dick Grindall lies,
Who was a rare game chicken.
So, so, friend Dick, an old chum cries,
The worms have pretty picking!
No Surgeon better lov’d himself;
He lov’d old rum and brandy
As much as misers do their pelf,
Or children sugar-candy.
And as for eatables—in short,
He lov’d both roast and boil’d;
Fish, flesh, or fowl, of any sort,
If not by cooking spoil’d.
But though full well he lov’d good cheer,
It was a venial fault;
Since Reason’s feast to him was dear,
Season’d with _Attic Salt_.
“He was an excellent surgeon of his day; that is, fifty years before
Abernethy or Cooper was dreamt of. He was also a great oddity,
but a perfect gentleman in his appearance and manner; never seen,
by any accident, but in a well-powdered wig, silk stockings, and
shoe-buckles. He practised in the City, when the city aristocracy
resided within its walls, and Haberdashers’ “Hall, in the season,
assembled all the wit, wisdom, and wealth of London merchants, in a
sort of conclave of saltatory civic magnificos.”
We just remember him, and that, after a long illness, he went round
in his carriage to return thanks for “obliging inquiries,” leaving
his card, on which was written, “the remains of Dick Grindall.”
The third and last work we have to notice, comes more legitimately
before us, and is a novelty in medical literature—a sort of _Sketch
Book_, containing much entertaining anecdote, that makes the
information it contains extremely amusing.
The work is divided into three parts, as the alliterated title
quaintly informs us—Mems., Maxims, and Memoirs. The first is a
chronological record, giving, as it were, a “bird’s eye view” of the
most interesting events in the history of medicine, from the time of
the conquest up to the [p336] present century. The second consists
of comments, or short essays, illustrative of some of the most
important facts; and the third of biographical anecdotes.
Under the head of “_Medical Books_,” we are presented with curious
specimens of our earliest writers, with comments; but let the author
speak for himself.
“One of the first of our English writers, is John of Gaddesden,
whose ‘Rosa Anglica,’ was greatly esteemed, and he is favourably
mentioned by Chaucer. John was a man to whom nothing came amiss; he
had an anodyne necklace for fits, and an infallible cataplasm for
gout; he was a dexterous bone-setter, and a good dentist. He was
very assiduous in inventing lotions for ladies’ complexions; and was
complaisant enough to cut their corns; and as for those troublesome
animalcules, which, in those days, used to infest _gentlemen’s_
heads, he had a most effectual method of destroying them; and
in his celebrated book, he favours us with a whimsical cure for
small-pox.—‘Immediately after the eruption, cause the whole body of
your patient to be wrapped in red scarlet cloth, or in any other red
cloth, and command everything about the bed to be made red. This is
an excellent cure. It was in this manner I treated the son of the
noble King of England, when he had the small-pox; and I cured him,
without leaving any marks.’
“Such was our countryman, John of Gaddesden, who deserves notice,
moreover, as being the first English surgeon employed at court; and
that the King (Edward III.) wrote a letter to the Pope in favour of
him.”
Speaking of Ardern’s manuscripts, he observes—
“These manuscripts, though they are more ludicrous than luminous,
are extremely well worth the attention of the surgical antiquary,
from the numerous illustrations they contain of the mode and manner
in which Ardern performed his operations; which, considering that he
was an _improver_ of surgery, gives us a glorious notion of what the
art was previously to John’s refinements, or those of Roger Franks,
whom he mentions with great praise.”
“ANATOMICAL LECTURES.
“When Dr. Hunter began his anatomical lectures, they were given
in the evening—but as he lived at the period when Garrick was in
his zenith, he soon discovered that he stood no chance with the
actor, for whenever Garrick _lectured_, the _anatomical lectures_
were neglected. In vain did the Doctor preach to the pupils on the
immorality of attending theatres, and the impropriety of neglecting
him; it was of no avail; Romeo’s apothecary and Dr. Last were the
only medical characters to spend the evening with, and for the rest,
they thought Macbeth sufficient authority, to ‘throw physic to the
dogs.’ [p337]
“For this reason, and for this reason alone, the anatomical lectures
were afterwards given in the middle of the day.
“Dr. Hunter may be considered as the father of the anatomical
schools of London, and he bequeathed a fame and character to his
class, which has been supported with undiminished lustre to the
present day. Previously to his time, very little had been done;
Cheselden had given a few lectures—so had André, and Nourse; and
Dr. Frank Nicholls gave what he considered a systematic course, and
published a Syllabus of thirty-nine lectures. Dr. Maclauren and
Dr. Marshal were also anatomical teachers. To the late Mr. Cline,
however, and to Mr. Abernethy, we are indebted for the anatomical
schools at two of our largest hospitals.
“Mr. Cline, it is true, found a place to lecture in, but it was his
great talents and his high character, that brought it into notice,
and subsequently, with Sir Astley Cooper, made it one of the first
schools in Europe.
“To Abernethy is due the sole honour of establishing the Anatomical
School at St. Bartholomew’s, now second to none; and it is to the
advantages arising from the hospital education of the metropolis,
that London has become, within the last half century, the most
distinguished seat of medical tuition in the world. Long may it
flourish!
‘Quicquid est laudabile, idem est beatum et florens.’—_Cicero_.”
“APOTHECARY.
“Apothecary, in its derivative sense, does not seem to allude
particularly to the sellers of medicines. Αποθηκη is of very
indefinite signification, (_Horreum_,) a market, shop, or
repository, which may be used or applied to any other business.
Chaucer and Pegge make it _Poticarry_, while some have derived it
from _A-pot-he-carries_, intimating, that they used to carry the
medicines themselves, as well as see them administered. ‘Give me an
ounce of civet, good apothecary,’ says Shakspeare.
“The ancient apothecaries were called ΡΙΖΟΤΟΜΟΙ, root-cutters; and
root-cutters they may still be considered; at any rate, no one
will deny to honest, herborizing Tom Wheeler, the character of a
primitive ΡΙΖΟΤΟΜΟΣ.
“That they may still be characterised by this appellation, their
‘herborizing walks,’ and their botanic garden at Chelsea, afford
very creditable proofs; nor is there any circumstance in the history
of the present worshipful society, that reflects more honour on
their zeal in promoting those branches of science, which appertain
to their avocation, than the disinterestedness and liberality with
which, during the last two centuries, they have maintained their
establishment at Chelsea.
“An active and intelligent member of their court has furnished them
with a very interesting and ample memoir on the subject, [p338] by
which it appears, that this expensive design was commenced at a time
when the society was without any disposable funds, when their hall
was burnt down in the memorable fire, and when they were obliged
to draw upon their own private pecuniary resources, to enable them
to enter on an undertaking, ‘whose principal design was honourable
reputation, without any prospect of worldly advantage.’
“Previously to the establishment of this garden, there had been
nothing of the kind, with the exception of a few private gardens,
the most conspicuous of which were those of the celebrated John
Gerarde, and the elder Tradescant; the former of these not then
being in existence, and the latter in a state of neglect and ruin;
and the locality of their position is now only known from the
records of the times.
“There was, however, besides these, a small garden in Westminster,
belonging to Mrs. Gape, the plants from which furnished the first
specimens for the Chelsea Garden. It appears from Evelyn’s journal,
that he paid old Mrs. Gape’s _medical garden_ a visit in June 1658;
whether he begged, borrowed, or bought any plants, does not appear;
that he had a very fine garden at Sayer’s Court, is well known;
but that he lent it to that royal barbarian, Peter the Great, when
he was studying ship-building at Deptford, is, perhaps, not so
generally known, nor, moreover, the return this royal carpenter
made to Evelyn’s politeness, or the manner in which he showed
his horticultural taste, in being wheeled through his landlord’s
ornamental hedges, and over his borders, in a wheel-barrow; a
circumstance which is recorded in a letter to the then Secretary of
the Royal Society.
“In France, the apothecaries were incorporated so early as 1484;
but it was not till the reign of King James the First, when the
metropolis abounded in dangerous empirics, who made and compounded
many ‘hurtful, false, and pernicious medicines,’ that the Worshipful
Society of Apothecaries were incorporated in London. Notwithstanding
a charter was given them to correct these abuses, it was found to be
nugatory with respect to those who were not members of the society;
and, although they made repeated applications to parliament, it
is only within these very few years that their powers have been
extended, and that they could legally enter the shop of any ‘person
or persons using the art and mystery of an apothecary, in any part
of England and Wales, for the purpose of searching, surveying, and
proving whether the medicines, wares, drugs, or any thing or things
whatsoever, in such shop or shops contained, and belonging to the
art or mystery of an apothecary, be wholesome, meet, and fit for the
cure, health, and ease of His Majesty’s subjects.’” [p339]
“TOBACCO.
‘Tobacco’s a physician,
Good both for sound and sickly;
’Tis a hot perfume,
That expels cold Rheume,
And makes it flow down quickly.’
“So says an old song, in an old play, and so said Dr. Ralph Thorius,
and the learned Dr. Everard, who wrote a book, entitled ‘Panacea, or
a Universal Medicine, being a Discovery of the wonderful Virtues of
Tobacco’ (1659); and in the frontispiece of his book, the Doctor is
represented with a pipe in his mouth. Dr. William Butler, styled,
by Fuller, the Æsculapius of his age, was also a great admirer
of tobacco, and that he might not smoke a dry pipe, he invented
a medical drink, called ‘Butler’s Ale;’ afterwards sold at the
Butler’s Head, in Mason’s-alley, Basinghall-street.
“Sir Theodore Mayerne gives a curious specimen of his tobacco
practice: ‘A person applying to him with a violent defluxion on his
teeth, Butler told him, that ‘a hard knot must be split with a hard
wedge,’ and directed him to smoke tobacco without intermission,
till he had consumed an ounce of the herb. The man was accustomed
to smoke; he therefore took twenty-five pipes at a sitting. This
first occasioned extreme sickness, and then a flux of saliva, which,
with gradual abatement of the pain, ran off to the quantity of two
quarts. The disorder was entirely cured, and did not return for
seventeen years.’
“Ant. Wood says, that he was much resorted to, ‘and had been more,
did he not delight to please himself with fantastical humours.’
“Many singular stories are related of him, perhaps they are
travelling stories, as may be conjectured, from the nature of the
prescription, when he ordered a lethargic parson to be put into the
warm carcase of a newly-killed cow!
“Fuller paints this humorist in striking colours, but observes,
‘that he made his humorsomeness to become him; wherein some of his
profession have rather aped than imitated him, who had morositatem
æquabilem, and kept the tenor of the same surliness to all persons.’
“The following extracts from _Letters from the Bodleian_, vol. ii.,
will give a notion of his _humour_, and of his mode of treating his
patients.
“‘Dr. Gale, of St. Paul’s schoole, assures me that a Frenchman came
one time from London to Cambridge, purposely to see him, whom he
made stay two houres for him in his gallery, and then he came out in
an old blue gowne. The French gentleman makes him two or three very
low bowes downe to the ground; Dr. Butler whippes his legge over his
head, and away goes into his chamber, and did not speake with him.
He kept an old mayd, whose name [p340] was Nell. Dr. Butler would
many times goe to the taverne, but drinke by himselfe: about nine or
ten at night, old Nell comes to him with a candle and lanthorne, and
sayes, “Come home, you drunken beast.” By and by Nell would stumble,
then her master calls her “drunken beast;” and so they did “drunken
beast” one another all the way till they came home.’
“‘The Dr. lyeing at the Savoy in London, next the water side, where
was a balcony look’t into the Thames, a patient came to him that
was grievously tormented with an Ague. The Dr. orders a boate to be
in readinesse under his windowe, and discoursed with the patient (a
gent.) in the balcony, when, on a signal given, two or three lusty
fellows came behind the gent., and threw him a matter of twenty feet
into the Thames. This surprise absolutely cured him.’
“‘A gent. with a red, ugly, pimpled face, came to him for a cure.
Said the Dr. “I must hang you.” So presently he had a device made
ready to hang him from a beam in the roome; and when he was e’en
almost dead, he cuts the veins that fed these pimples, and lett out
the black ugly blood, and cured him.’
“Butler must have been a man of abilities, for the Lord Treasurer
Burleigh wrote to the President of the College of Physicians,
desiring that Butler might be allowed to practice in London
occasionally, and he was consulted, with Sir Theodore Mayerne and
others, in the sickness that proved fatal to Prince Henry; and it
is reported that Butler, at first sight of him, gave an unfavorable
prognostic. The account of this case affords such an excellent
notion of the consultations and practise of the doctors of those
days, that I am induced to give it as stated in the ‘Desiderata
Curiosa.’
“_The Manner of the Sickness and Death of Prince Henry, 6th Nov._
1612.
“‘Dr. Atkins, a Physician of London, famous for his practyce,
honestie, and learninge, was sent for to assiste the reste in the
cure.
“‘He got worse, whereupon bleedinge was again proposed by Dr.
Mayerne, and the favorers thereof, alledging that in this case of
extremity, they must (if they meant to save his life) proceed in the
cure, as though he was some meane person.
“‘This was not agreed to, and next day, the Physicians, Chirurgeons,
and Apothecaryes seemed to be dismayed, as men perplexed, yet the
most part were of opinion, that the crisis was to been seene before
a final dissolution. _This day a cock was cloven by the backe, and
applyed to the soles of his feete_. But in vayne. Shortly after it
was announced that all hope was gone. His Majestie then gave leave
and absolute power to Dr. Mayerne, to do what he woulde of himselfe,
without advise of the rest; but the Doctor did not it seems like
this, “for hee, weighing the greatness [p341] of the cure and
eminencye of the danger, would not, for all that, adventure to doe
any thinge of himself, without the advice of the rest, saying,
that it should never be said in after ages, that he had kylled the
Kynge’s eldest sonne.”
“‘Bleeding was again proposed by Mayerne, but Doctors Hamond,
Butler, and Atkins could not agree about it; instead of which they
doubled and tripled the cordials.
“‘Then came to assist the rest, Dr. Palmer and Dr. Giffard, famous
physicians for their honestie and learninge. The result of this
consultation was _Diascordium_, which was given in the presence of
many honourable gentlemen.
“‘All sorts of cardials were sent. _Sir Walter Rawleigh_ sent one
from the Tower.’”
“MRS. MAPP.
“No part of surgery is supposed to be so easy to understand as
_bone-setting_; it is regarded by a considerable part of the people
as no matter of science, an affair on a level with farriery, as
easily learnt, and like a heritage, to be transmitted from father to
son; in short, the pretensions of these people are very like those
of the man who set up as an oculist, _because_ he had _lost an eye_,
or the rupture doctor, who cured _bursten_ children, _because_ his
grandfather and grandmother were both _bursten_.
“We are not without plenty of ignorant and impudent pretenders at
the present day, but the celebrated Mrs. Mapp, the bone-setter of
Epsom, surpasses them all. She was the daughter of a man named
Wallis, a bone-setter at Hindon, in Wiltshire, and sister to the
celebrated ‘Polly Peachem,’ who married the Duke of Bolton. Upon
some _family quarrel_, Sally Wallis left her professional parent,
and wandered up and down the country in a miserable manner, calling
herself ‘Crazy Sally,’ and pursuing, in her perambulations, a
course that fairly justified the title. Arriving at last at Epsom,
she succeeded in humbugging the worthy bumpkins of that place so
decidedly, that a subscription was set on foot to keep her among
them; but her fame extending to the metropolis, the dupes of London,
a numerous class then as well as now, thought it no trouble to go
ten miles to see the conjuror, till at length, she was pleased
to bless the afflicted of London with her presence, and once a
week drove to the Grecian Coffee-house, in a coach and six, with
out-riders! and all the appearance of nobility. It was in one of
these journeys, passing through Kent-street, in the Borough, that
being taken for a certain woman of quality from the Electorate in
Germany, a great mob followed, and bestowed on her many bitter
reproaches, till Madame, perceiving some mistake, looked out of the
window, and accosted them in this gentle manner: ‘D—— n your bloods,
don’t you know me? I am Mrs. Mapp, the _bone-setter_!’ upon which,
they instantly changed their revilings into loud huzzas.
“That she was likely enough to express herself in these terms,
[p342] seems very natural from her origin and history; but that
she should be on visiting terms with decent people, and keep
quality company, is as unnatural. Mr. Pott, who wrote with the pen
of a master, has noticed this in no very gracious terms:—‘We all
remember,’ says he, ‘that even the absurdities and impracticability
of her own promises and engagements, were by no means equal to the
expectations and credulity of those who ran after her; that is,
of all ranks and degrees of people, from the lowest labourer or
mechanic, up to those of the most exalted rank and station; several
of whom not only did not hesitate to believe implicitly the most
extravagant assertions of an ignorant, illiberal, drunken, female
savage, but even solicited her company; at least, seemed to enjoy
her company.’”
“TAR WATER.
“Bishop Berkeley, who brought this remedy into fashion, was
greatly aided by the faith of the clergy, who preached it up in
all quarters. Among these, none was more strenuous than Dr. Young,
the author of the ‘Night Thoughts.’ ‘They who have experienced the
wonderful effects of tar water,’ says he, ‘reveal its excellencies
to others. I say reveal, because they are beyond what any can
conceive by reason or natural light. But others disbelieve them,
though the revelation is attested past all scruple, because to them
such strange excellencies are incomprehensible. Now give me leave to
say, that this infidelity may possibly be as fatal to morbid bodies,
as other infidelity to morbid souls. I say this in honest zeal for
your welfare. I am confident, if you persist, you’ll be greatly
benefited by it. In old obstinate chronical complaints, it probably
will not show its virtue under three months; tho’ secretly, it is
doing good all the time.’
“Such was the universality of its power, that it was good for man
and beast, _and a sure remedy for the plague_!”
After this miscellaneous and amusing collection, we arrive at the
Memoirs, which is not a dry, biographical record of birth, death,
parentage, and education, but a lively sketch of characteristic
particulars of eminent medical men. We will select a few of them.
“BUTTER.
“Mr. John Whitehurst (author of an ingenious theory of the earth)
was the means of Dr. William Butter’s settling at Derby, where he
(Mr. W.) then resided. Mr. Whitehurst had met at Buxton with Lord
Hopetown, who had asked him what physicians were at Derby, and upon
his telling him, that there could not be a finer opening, as the
two physicians there had both declined practice, his Lordship said
it would be a good place for Butter; and shortly afterwards, the
Doctor made his appearance loaded with recommendations, and among
others, with one from Dr. Hope [p343] to Mr. Whitehurst. Mr. W. was
very civil to him, but before he had been a fortnight in the town,
Butter came and complained, that he had not had a single patient.
Mr. W. told him, that he could hardly expect any so soon, that he
must be known a little, and so on, which so offended Butter, that
ever afterwards he considered Mr. W. as his enemy. He was very rude
and coarse in his manner, always averse to consultations, and used
to say, that nobody but himself and Sir John Pringle knew any thing
of physic. Among his patients at Derby were two brothers, opulent
men, who lived together; one of them being dangerously ill, and
attended by Butter, the other brother sent a messenger to Birmingham
for two physicians, and then told Butter what he had done, and
that he intended to have a consultation. Butter immediately went
to the apothecary, and got some laudanum, of which he gave large
doses to the patient, so that when the Birmingham physicians came,
the patient was in a state of lethargy. They asked if he had been
taking opium, but Butter denied that any had been given; it was
accidentally discovered, however, by means of the apothecary, and
from that time Butter, who was before in excellent practice, lost
considerably in public estimation.
“A tailor at Derby, whom Butter had offended, once played him
a trick. A curer of smoky chimnies came to Derby, and one day,
when the tailor knew the Doctor was out of town, he called on the
chimney-man, and told him that Butter had desired to have a smoky
chimney cured, belonging to his best parlour; and had left positive
orders that he should go to his house and set about it immediately.
The operator accordingly went, delivered his message to Butter’s
servant, pulled out his utensils, and fell to work; and in a short
time the marble slab, and other ornaments of the chimney, were down.
Butter came in while he was engaged in this business; finding his
parlour full of bricks and dirt and mortar, his fury was excessive,
and his hatred to the tailor was ever after implacable. The story
got wind in the town, and the boys in the street would sometimes
talk about _chimney-doctors_ as he passed.
“Butter lived close to a churchyard, and one day, seeing a
grave-digger at work, he asked him for whom he was digging the
grave—‘For so and so,’ said the grave-digger, naming the tailor who
had so highly offended him, which so pleased the Doctor, that he
gave the fellow a shilling. This occasioned a fresh laugh at his
expense, as the tailor was in good health, and it was merely a piece
of pleasantry of the grave-digger’s. Butter and his wife lived in
the most frugal manner, and never visited anybody. After he came to
London, a lady of fortune, who had been his patient in Derbyshire,
and wished to countenance him, invited him often to her table, till
at length Butter brought in an account of fees for each visit.”
[p344]
“CADOGAN.
“Universal temperance in eating and drinking has been considered
as particularly incumbent on a physician, in every period of his
practice. It is a virtue he is frequently obliged to inculcate on
his patients; and his doctrines will have little effect if they be
not regularly exemplified in his own conduct.
“Dr. Cadogan, however, thought it right to _try all things_, and
considered it his duty to speak _experimentally_ on both sides of
the question, to qualify himself to say, in the language of Dido,—
‘Non ignara mali miseris succurrere disco.’
“Thus, dining one day at a College dinner, after discoursing most
elegantly and forcibly on abstinence, temperance, and particularly
against pie-crust and pastry, he is reported to have addressed a
brother M.D. in the following terms: ‘Pray, doctor, is that a pigeon
pie near you?’ ‘Yes, sir.’ ‘Then I will thank you to send me the
hind-quarters of two pigeons, some fat of the beef-steak, a good
portion of the pudding-crust, and as much gravy as you can spare!’”
“BLAIR.
“‘We physicians were always politicians,’ was a favourite expression
of Warren’s, but nevertheless, there are very few instances of
medical men embroiling themselves in political troubles.
“Dr. Patrick Blair, however, who was in the rebellion of 1745, got
himself into Newgate, and was condemned to be hanged. In the British
Museum are several of his letters to Sir Hans Sloane, written in
prison, soliciting his intercession, and in one of them he writes,
‘If you come towards Newgate, I hope you will favour me with a
call.’ Dr. Martyn, the professor of Botany at Cambridge, supped with
him in Newgate the night previous to his expected execution. Blair
had been all along confident that he should be reprieved: Dr. Martyn
said, he sat pretty quietly till the clock struck nine, and then he
got up and walked about the room; at ten he quickened his pace; and
at twelve, no reprieve coming, he cried out—‘By my troth! this is
carrying the jest too far!’ The reprieve, however, came soon after,
and in due time a pardon. Blair went afterwards, and settled at
Boston in Lincolnshire, where he practised till his death.”
“SIR WILLIAM DUNCAN.
“Sir William Duncan once met Dr. Thomas Reeve, when the latter was
President of the College, and insisted that his name should not
follow Reeve’s, because he was physician to the king. Reeve asserted
his dignity as president, and the consequence was, that each wrote
his own prescription (the same they had agreed to) and gave it to
the apothecary.
“There are many instances of medical etiquette being carried to a
great extent, but polite etiquette in a sick room was perhaps [p345]
never exceeded by the following exhibition of it, between the Duke
of Ormond and a German Baron.
“The Duke of Ormond and a certain German Baron were both considered
models of pride and politeness. When the Duke perceived that he
was dying, he desired that he might be seated in his elbow chair,
and then, turning to the Baron, with great _courteousness_, he
requested that he would excuse any unseemly contortions of feature,
as his physicians assured him, that he must soon struggle with the
last pangs. ‘My dear Lord Duke,’ replied the Baron, with equal
_politeness_, ‘I beg you will be on no ceremony on my account!’”
“BAILLIE,
“Not Matthew Baillie, but an Irish gentleman who had been rejected
by the College, called the next day on Dr. Barrowby, who was one of
the censors, and insisted upon his fighting him. Barrowby, who was a
little puny man, declined it. ‘I am only the third censor,’ said he,
‘in point of age—you must first call out your own countryman, Sir
Hans Sloane, our president, and when you have fought him and the two
senior censors, then I shall be ready to meet you.’
“Many medical duels have been prevented by the difficulty of
arranging the ‘methodus pugnandi.’ In the instance of Dr.
Brocklesby, the number of paces could not be agreed upon; and in
the affair between Akenside and Ballow, one had determined never to
fight in the morning, and the other that he would never fight in the
afternoon. John Wilkes, who did not stand upon ceremony in these
little affairs, when asked by Lord Talbot, ‘How many times they were
to fire?’ replied, ‘Just as often as your Lordship pleases; I have
brought _a bag of bullets and a flask of gunpowder_.’”
“WOODVILLE.
“Dr. Joseph Adams, who was much with Woodville just before his
death, used to relate several traits of his firmness and seeming
unconcern with respect to death. Woodville lived in lodgings at a
carpenter’s in Ely-place, and Adams, a few days before his death,
advised the matron of the Small-pox Hospital to invite him to have
a bed made up there, that he might be better attended to: this she
did, and Woodville accepted it. He observed to Adams, the next day,
that he was a poor man come to die at the hospital, and he remarked,
that some of those who called on him flattered him with hopes of
his getting better. ‘But I am not so silly,’ he said, ‘as to mind
what they say; I know my own case too well, and that I am dying. A
younger man with better stamina might think it hard to die; but why
should I regret leaving such a diseased, worn-out carcase as mine?’
“The carpenter with whom he lodged had not been always on the best
terms with him; Woodville said he should wish to [p346] let the
man see that he died in peace with him, and as he never had much
occasion to employ him, desired he might be sent for to come and
measure him for his coffin. This was done; the carpenter came, and
took measure of the Doctor, who begged him not to be more than two
days about it; ‘For,’ said he, ‘I shall not live beyond that time;’
and he did actually die just before the end of the next day. He
got between one and two thousand pounds by his Medical Botany, and
with the money bought a small estate, which he left to his natural
daughter, being all the property he possessed.”
We happen to know this fact, and moreover, that the Doctor was
playing at chess when the carpenter was introduced to measure him
for his wooden surtout. “Mr. ——,” said the Doctor, “you come at the
proper season, for _my game is nearly finished!”_
The work is embellished with three etchings, which remind us that Mr.
Wadd not only uses the pen, but the pencil, with facility and taste.
His published works afford ample proof of his power of _illustrating_
morbid anatomy, but we happen to know of some _unpublished folio
proofs_ of equal merit. To his fair fame as a surgeon, by the works
we have just noticed, he may add the reputation of being one of the
most vivacious literary _illustrators_ of his art.
_On Tic Douloureux_.
SIR,
PRESUMING that popular and domestic medicine may occasionally find a
niche in your Journal, I beg to offer a few remarks upon the above
complaint, which has lately become, as it would appear at least,
singularly prevalent; and as I address myself to general readers,
I shall avoid all learned terms of art, and minute descriptions
requiring them. The genuine tic douloureux is usually considered
as a morbid affection of the nerves of the face, very commonly
attacking the circumference of the orbit, and producing frequent
and violent paroxysms of excruciating pain; the disease, however,
varies considerably in intensity, and sometimes bears the same
name when attacking other parts; it frequently occurs under the
integuments of the head, and may or may not be attended with external
tenderness. Though opiates relieve the pain, they are ineffectual as
to its cure. Peruvian bark, in [p347] various forms, has sometimes
afforded relief, and preparations containing the metallic tonics,
more especially the oxides of iron, have been regarded as giving
more permanent and beneficial assistance. Local remedies are of very
uncertain utility, and electricity and galvanism have generally done
more harm than good. The division of the nerves has been resorted
to, but never with permanent, and often not even with temporary
benefit. The cause of the disease is unknown, and though sometimes
organic derangement would appear to excite it, no plausible source
of the mischief can usually be discovered. The patient’s principal
solace is that the disorder frequently wears itself out, and as far
as my experience goes, the less we rely upon individual remedies, the
better—the main thing being strict attention to the general health,
and especially to the state of the stomach and bowels. These remarks
apply to the genuine Tic Douloureux; but it has of late years been
the fashion in physic to give that alarming name to a variety of
painful affections, resulting from very various causes, by which
much needless uneasiness has been given to the patient, and which
has often led to erroneous and even mischievous systems of practical
treatment. As cases of this kind are of every day occurrence, a short
notice of them can scarcely be inappropriate to a Journal, the chief
object of which is to familiarize every branch of science.
Rheumatic affections of the head and face often put on the appearance
of Tic; like it, they come on at short intervals, and are limited
to a small space; there is, generally, more or less of external
tenderness, sometimes confined to spots upon the face and scalp, not
larger than a shilling; at others, more diffused. More or less of
this is usually attendant upon habits subject to chronic rheumatism,
and it not uncommonly is the leading feature of the complaint. The
internal use of opiates and sudorifics, especially small doses of
Dover’s powder, warm fomentations, and keeping the head, especially
at night, wrapped up in flannel, are sovereign remedies.
But the most common cases of painful affections, mistaken for
Tic, are those which occur in nervous and irritable persons, and
especially amongst men of business, statesmen, lawyers, merchants,
over-studious persons, and all whose minds are [p348] occasionally
exercised beyond their powers, who are subject to reverses of
fortune, or sudden changes in the posture of their affairs, and who
are constant objects of public attention, praise, or censure. For a
time, the constitution, if a good one, bears up against such wear
and tear, but as you advance, one or other symptom of a shattered
nervous system appears, and this, more quickly and certainly, where
the body has been pampered by too good living, false spirits excited
by indulgence in wine, and fatigue relieved by narcotics, instead of
sleep. Among the host of disordered affections to which such persons
are liable, violent local nervous pains are most common, but they are
invariably relieved by such means as contribute to quiet the mind and
invigorate the body. Abstinence from business, retirement into the
country, regular hours, plain food, moderate exercise, and avoiding
excitement, are here certain remedies, and indeed the only ones, but
they are unfortunately not always easy of attainment, and sometimes
altogether unattainable. I have, however, mentioned these cases, to
enjoin an early attention to the overhanging evil, and to criticise
its improper treatment. I would, upon the first point, enjoin early
attention to the first symptoms, and when they appear let the
individual seriously ask himself whether it be worth while to gain
a little more money, glory, or honour, or renown, at the expense of
all future comfort, and a painful, wearisome, and probably shortened
existence; or whether such apparent advantages had not better be at
once conceded, and the host of evils, which will almost certainly
ensue, warded off by a timely retirement? I could illustrate this
subject by reference to many individuals, especially in the legal
and medical professions, some of whom are harassing themselves to
death by over-exertion, whilst others (I regret to say but few) are
preserving a healthy constitution, by sacrificing a certain share
of fame and emolument: the exceeding folly, too, of persevering in
business, when neither mental nor bodily powers are adequate to the
exertion, might here be animadverted on, but I must, for the present,
waive such topics, and return to the treatment of those nervous
pains called Tic Douloureux, which are of such common occurrence in
the cases alluded to. These will certainly give way under [p349]
that quiet and retirement which has been above recommended; but it
is really provoking to see such means so commonly neglected, and
the unfortunate patients tormented by blisters, fomentations, and
galvanism, and their already debilitated stomachs further overpowered
by gigantic doses of powdered bark, rust of iron, and other (in such
cases) equally ineffective and hurtful medicines. I write to warn
against them.
I have spoken of Peruvian bark as a remedy in tic douloureux. Where
the painful affection so called, let it arise from what cause it
may, assumes an intermitting form,—and nothing is more common than
to have it coming on at stated periods, generally one violent attack
in the twenty-four hours,—in such, as in other similar cases, bark
has often been effective; but of late, sulphate of quinine has very
properly been substituted for it; and as this extremely curious and
valuable medicine is now in every one’s hands, and even finding its
way into family medicine chests, a few words respecting its use, or
rather abuse, may not be here misplaced. I would first remark, that
it is too commonly given in over-doses: it then produces thirst,
and a white tongue, and, what is remarkable, it excites in most
people that uneasy sensation of fulness about the stomach, which is
generally complained of after a large dose of powdered bark, and
ascribed to the indigestible nature of the large quantity of inert
and insoluble woody fibre in which that substance abounds. For these
reasons sulphate of quinine is too often laid aside in cases where,
if properly and judiciously administered, it might prove of important
service; instead of three or four grains, or even more, repeated
every four or six hours, let a grain be given once a day; and if
it agree, and occasion require, let this dose be repeated twice or
thrice daily, either in the form of pill or solution. I prefer the
latter; two drachms of tincture of orange-peel being used as the
solvent, and diluted afterwards with half a wine-glass of water. It
is not meant here to insinuate, that in obstinate agues, and other
disorders, large doses of quinine are always improper, but to enforce
the occasional mischief which they produce, and by which the medicine
is unjustly brought into distrust and disrepute.
Decayed teeth are fertile sources of pains and twitches [p350] about
the facial nerves and muscles, analogous to Tic; and great irritation
from inflamed membranes of some cavity in the upper jaw has also
occasioned them. I knew a person who suffered six months from such an
attack, and for whom a physician prescribed, in the course of that
period, some pounds of carbonate of iron. Symptoms then ensued, for
which a course of sarsaparilla was ordered, but it was of no avail.
Mercurials were then given, with manifest mischief. The extraction
of the second grinder effected a permanent cure; its roots were
connected with a cavity of fetid discharge, which had no sooner vent,
than all the symptoms disappeared.
Without exceeding the limits which I have set myself, I cannot
proceed farther in these remarks; but I hope enough has been said to
quiet the apprehensions of some invalids who suffer themselves to
be exceedingly alarmed at the name given to their complaint, and to
be dosed with large quantities of useless medicines, which rather
aggravate than relieve it. In many of these cases, the less that is
done the better; in all of them, careful reference must be had to
the real exciting cause; and, in addition to the other circumstances
adverted to, a strict attention to diet must be enforced, and more
than ordinary watchfulness exerted over the state of the stomach
and bowels: plain roast and boiled, and no grease or piecrust in
the former; and for the latter, an occasional blue pill and a tea
spoonful of Epsom salt.
MEDICUS.
_Remarks on some Quadrupeds supposed by Naturalists to be extinct_.
By John Ranking, Esq.
There is not any part of the creation more interesting to mankind
than the gigantic classes of quadrupeds. In them, we are able to
contemplate the power of the Creator of all things, in one of the
most magnificent exercises of his will. Such, however, is the limit
to this kind of knowledge, that there is probably not any one class,
even of the largest quadrupeds, all the _species_ of which are, or
possibly ever can be, known to the student of natural history. More
than half of [p351] the surface of the earth is still undiscovered
by the civilised portion of its inhabitants: regions as extensive
as Europe, in Asia, Africa, and America, are, at this time, either
wholly unknown or undescribed.
The imperfection of history is such, that the most civilised ancient
states of the world have left little behind but what may be called
fragments of their annals. If we include the Gothic age, as it is
called, from the fifth to the fifteenth century, there are not less,
out of the fifty-eight centuries which the earth is said to have
existed, than forty of them which may be termed a blank, as far as
regards profane and natural knowledge.
The period assigned to the Deluge is seventeen centuries after the
creation, or upwards of four thousand years past. There are not any
known real historical annals that can contest this event, and the
natural state of the earth offers abundant proofs of its reality.
Under all these considerations, the fossil remains of elephants and
other large quadrupeds, known to have been employed or slain by
the Romans and Moguls, may justly be considered as independent of
any relation to that catastrophe, and in no wise concerned in the
discussion. Established truths are rather disturbed and weakened by
arguments which are open to refutation.
The time is not distant when it will be generally acknowledged that
all those kinds of quadrupeds, the remains of which have been found
at the very places mentioned in history, are still in existence; a
fact which, when proved, will be of infinitely greater interest as
it regards so grand a portion of nature, than the single supposition
that they are all extinct, because we are not acquainted with the
exact species which corresponds with many of the fossil kinds
frequently discovered: this being the foundation on which such a
conclusion is principally built.
Naturalists have endeavoured to prove that such bones are found where
they could only have been placed by the Deluge: but the changes in
the surface from deposits by rivers, earthquakes, and imperceptible
alterations from the accretion of vegetable matter, and from dust,
volcanoes, digging of mines, wells, canals, foundations, and other
disturbances of the soil, [p352] are such as cannot be observed or
registered; and a few lines will prove how difficult and uncertain
this part of the question remains to this day.
“In quarrying limestone at Aix, in Provence, A.D. 1788, under eleven
strata, separated from each other by a bed of sand and clay, at the
depth of forty-five feet, the surface was covered with shells. The
stones of this bed being removed, under a stratum of argillaceous
sand, stumps of columns and fragments of stones, like the quarry,
half wrought, were found; and also coins, handles of hammers, and
a board, one inch thick and seven feet long, broken, but all the
pieces there, and could be joined; it was like the boards used by
quarry-men, and worn in the same manner. The pieces of wood were
changed into _agate_[53].”
“On sinking a well on a hill near Tobolsk, sixty-four _fathoms_ deep
in the earth, an oaken beam was found; it was quite black, and not
round but shaped[54].”
“At Watlington-park, Oxfordshire, at fifty or sixty feet depth, many
whole oaks, hazel-nuts, a stag’s-head and antlers, were found, and on
the same spot two Roman urns[55].”
“In Oxfordshire there is a tumulus which has become a perfect mount
of stone.”
“Ralph, the brother of Earl Widdrington, showed me many _human_
bones taken from whole skeletons, with British beads, chains, iron
rings, and brass bits of bridles, dug up in a _quarry_ at Blankney,
Lincolnshire, which was probably plain mould when these old corpses
of the Britons were interred: and I Saw many _human_ bones and
armour, with Roman coins, fibluæ &c., found in a _stone_-pit in
Hunstanton-park, Norfolk, belonging to Sir Nicholas L’Estrange[56].”
Very numerous instances could be added, in order to prove that
the local circumstances, when skeletons of these quadrupeds are
found, are not of a nature to disprove the _historical_ origin of
fossil bones. From the highest authority we learn, that the “bones
of species which are apparently the same with [p353] those that
still exist alive, are never found except in the latest alluvial
depositions, or in the fissures of caverns and rocks, in places where
they may have been overwhelmed by debris, or even buried by man[57].”
Thus it appears that a comparative view of the exact _species_ now
living, with that of the fossil remains, is what we must depend on to
decide whether the fossil kinds may not be still in existence.
With respect to the very numerous theories of the earth, the
last, by Werner, has been confidently quoted in opposition to the
writer’s historical proofs[58]. But Werner himself, before his
death (in 1817), tacitly acknowledged that it is not a tenable
doctrine, and which is clearly indicated by the compilers of REES’s
_Cyclopedia_[59], although it is generally allowed to be the best
extant. This hypothesis was formed on a circumscribed view of the
strata in Saxony, but it is found to be quite inapplicable, in
America for instance[60]. To account for fossil bones of elephants,
&c., being found high in the north, the American author who
discovered this defect in the geological doctrine, conjectures that
those large quadrupeds may have migrated, like the buffalos, during
the change of seasons. This notion, however, would not apply to Asia,
the native countries of those animals being well supplied with leaves
or other food the year round.
With these prefatory remarks some historical proofs are offered, for
the probability of the following animals found in a fossil state, not
being of extinct species, beginning with the
ELEPHANT.
“On sinking the foundation for a mill, near the side of a small brook
in the Bishop of Kilmore’s lands, at Maghery, [p354] eight miles from
Belturbet, in the north of Ireland, A.D. 1715, four large teeth were
found, with a piece of the under jawbone and part of the skull of a
young elephant. The teeth were more solid and petrified than when in
a natural state.”
[Illustration: A]
Fig. A is one of the above grinders. B is a fossil grinder in the
possession of the Royal Society. C is the grinder of an elephant
between 10 and 11 feet high, the entire skull of which was then in
Westminster[61].
[Illustration: B]
[Illustration: C]
It is thus apparent that two _fossil_ elephants are of the same
species as those now in existence.
It is not improbable that the Maghery animal was conveyed to Ireland
as a present, or for exhibition. “Fiacra, son of Eacha Moymedon, was
mortally wounded at the battle of Caonry, which was fought A.D. 380,
wherein he was victorious against the army of Momonia, (Munster). On
his return to Hy-mac-uais, in _Meath_, he died of his wounds. His
funeral [p355] leacht was erected, and on his tomb was inscribed his
name in the Ogham character[62].”
We here find that the native sovereign of the northern part of
Ireland resided in Meath, the borders of which county are not
many miles from the place where the elephant was found. It was at
about the year of the battle of Caonry that Maximus, the emperor
in Britain, aspired to be master of the Roman empire. Finding the
union of the Scots and Picts prevented his peaceable possession of
Britain, which was a great obstacle to the execution of his project,
he persuaded the Picts to join their forces to his, on the promise of
giving them the lands of the Scots. The Scots were thus overpowered,
and were forced to fly to Ireland and the adjacent isles. The Scots,
being assisted by the Irish, invaded the north, and were driven
back to Ireland by Maximus, at the head of his troops. The emperor
threatened to invade Ireland, and punish the Irish; but the dread
they had of the presence of a Roman army, induced them to grant
Maximus his own terms, which, in order to conciliate all parties,
were moderate[63]. Now it is by no means impossible that the British
emperor, on this conciliating occasion, sent this very elephant to
his Irish majesty. Tacitus observes, that Agricola (three centuries
before Maximus) received an expelled petty king of Ireland into his
protection; that in manners the natives vary little from the Britons;
and that _the ports and landings of Ireland are better known, through
the frequency of commerce and merchants, than those of Britain_[64].
THE MASTODON.
This quadruped is now known not to differ from the elephant, except
in the form of the grinders, and has probably been called by the name
of elephant by the Romans. Remains of the mastodon have been found
mixed with those of the elephant, in Europe, Siberia, and America;
and for the following [p356] reasons there is every probability of
this animal being in existence.
Captain C. S. Cochrane, in his _Journal in Colombia_, vol. ii., p.
390, relates that numbers of the _carnivorous_ elephants have been
seen feeding on the plains at the foot of a ridge of mountains, at
Choco, in New Granada. “Part of the foot of a mastodon, with five
nails attached, was found in a cave, with a tooth, by a savage west
of the Missouri: it was very fresh, and perfectly resembling that of
an elephant: it was obtained of a Mexican, who had purchased it of a
native[65].”
“The native Americans describe the elephant as still existing in the
northern parts of their country (the Missouri).”—Mr. Jefferson’s
_Notes on Virginia_, p. 57.
Many bones of the mastodon were found in the county of Wythe,
Virginia, with a mass of half-ground branches, roots, and leaves,
enclosed in a kind of sack, supposed to be the stomach, in the midst
of them; so as to leave no doubt that they were substances which the
animal had devoured, and among them were distinguishable the remains
of some plants known in Virginia[66]. Teeth of the mastodon have
been found in Little Tartary, (for five centuries possessed by the
Moguls,) in Siberia, near the Oural mountains, and one at Harwich, in
England[67].
There, have been brought from Ava, found on the left bank of the
Irawaddy, in N. lat. 20° to 21°, near the wells of petroleum, in
narrow ravines, sand-hills, beds of gravel, ironstone, and calcareous
breccia, evidently a _diluvial_ formation,—fossil bones, shells, and
wood. Bones of the mastodon, equal in size to those of the Ohio,
a grinder 16-1/2 inches in circumference, a humerus, measuring 25
inches round the condyles, with several [p357] grinders and bones
of younger individuals, and fragments of tusks: fossil molares of
the rhinoceros, resembling two species of a genus named by Cuvier
Anthracotherium: bones like an animal of the horse kind: remains of
crocodiles, supposed to be the gavial, or long-nosed alligator of the
Ganges, (not now known in the rivers of Ava.) The fossil bones were
upon or near the surface, more or less exposed, not decomposed or
rolled, and are of animals that died there. The bones are petrified,
and deeply coloured with iron, the substance siliceous and very
hard. The blocks of wood are larger than the trees growing there,
but it is not known if they are of the same kind. “An idle notion is
entertained by many, that these fossil remains have been generated by
a petrifying quality in the water of the Irawaddy[68], but I think
they are the result, as elsewhere, of one of the last catastrophes;
in fact, the remains of a former world, before man was called into
existence.”—_Morning Herald_, Sept. 14, 1827.
Bones of the mastodon have been found in Europe, mixed with menagerie
collections, which cannot possibly be attributed to any other origin
than that of sports of the amphitheatre. They are found in western
Siberia, which was conquered by Sheibani, Genghis Khan’s grandson,
A.D. 1242, and held 300 years, and whose first capital was at
Tiumin[69], on the river Tura, near the Ural mountains, where the
remains of the mastodon were found. Ava was conquered by the Grand
Khan Kublai in 1272, in a battle with the king of eastern Bengal,
in which there were a thousand elephants[70]. The places where they
have been found in America correspond with history and tradition so
faithfully, as to assist the other numerous proofs of Mexico and
Peru having been conquered by the Moguls, in the year 1283, and
the bones of the mastodon are there found, as well as remains of
_elephants, precisely like those of Siberia_[71]. With regard to the
tooth found at Harwich, the [p358] British kings Cuneboline[72] and
Arviragus had representations of elephants on their coins. The bones
of elephants, rhinoceroses, and crocodiles found in Ava are not,
as those found in Europe and Siberia, what are termed _extraneous_
fossils; the same kinds of animals being natives of the spot in Ava.
The one like the horse cannot be ascertained; but the kings of Pegu,
in former times, had camelopards, and, therefore, probably, zebras in
their _calichars_, or parks; they also had _unicorns_, ostriches, and
rein-deer[73]. Timur Khan, grandson of Kublai, who invaded Siberia
with such powerful armies, resided at Tali, in Yunan, N. lat. 25°
east of the Irawaddy[74].
The writer is of opinion that all those fossil bones found in Ava are
of species still in existence: they may have floated down from more
northern parts, the river in question being as long as the Ganges,
said to be navigable into China; and has its source in Thibet,—(see
RENNELL’s _Memoir_, p. 217.) According to the hypothesis of the
writer, Montezuma’s ancestor was a Mongul grandee from Assam; and
mastodontes’ remains have been found in Mexico, and those beasts are,
as above related, supposed to be found alive near the Missouri.
This is the first instance the writer has met with of similar bones
not being _extraneous_; and is, therefore, a remarkable fact, which
excites the strongest suspicion that their species are still living.
Ava is a new world on a small scale, and this collection of bones
will, very probably, at no distant date, lead to positive proof of
the existence of other quadrupeds, now conjectured by naturalists
to be extinct. With respect to the local position, it is in all
probability the old bed of the river, as [p359] the beds of those in
Asia change in a wonderful manner.—(See _Rennell_, p. 255.)
A skeleton of an elephant or mastodon, for it is not known which,
was found in a tomb in Mexico, which had evidently been built on
purpose.—(_Clavigero_, vol. i., p. 84.) No authority whatever
dates the foundation of Mexico earlier than A.D. 1324. The Aztecs
advanced from Culiacan, when they took possession of the marshes,
and founded Mexico: other Aztecs had preceded them who had arrived
by land; but the writer hazarded a theory[75] that _Montezuma’s_
ancestors had, like those of the Natchez and of the Incas, arrived
in America by _sea_ with elephants, under Mango Capac; and he has
had the satisfaction to find a confirmation of his conjectures in
a _decade_ written by Peter Martyr, the Milanese, (employed by
Ferdinand V., King of Castile and Arragon, and who died in the year
1526,) addressed to Adrian VI., who had been co-regent of Spain with
Cardinal Ximenes. “Montezuma spoke thus to Cortez:—We have heard
by our ancestors that we are strangers. A certain great prince, in
_ships_, before the memory of all men living, brought our ancestors
unto these coasts; whether voluntarily or driven by tempest it
is not manifest; who, leaving his companions, departed into his
country, and, at length returning, would have had them to have gone
back again. But they had built houses, and joining themselves with
the women of the country had begotten children, and had settled.
Wherefore our ancestors, having chosen a senate and princes to
govern the people, refused to go, and he departed with threatening
speeches. Never any appeared unto this time who denied the right of
that captain and commander. We think, therefore, that the king who
sent you derived his descent from him, and all the kingdoms which we
possess are yours[76].” It is impossible to know clearly what the
allusions to the return of the great commander may mean, but whatever
it be, it does not change the date. As the Mexicans considered
Cortez to be a child of the sun, the _great prince_ must have been a
descendant from Genghis Khan; and _thence_ the [p360] terrors and
submission of Montezuma and the Mexicans, who had always dreaded such
a visit.
The Aztecs had sojourned in Culiacan and other places, from the date
of the arrival of the ships, till they proceeded to Anahuac. The
foundation of Tenochtitlan (or Mexico) having been in 1324, and the
first king, Montezuma’s ancestor, elected in 1377; therefore, the
empire, when Montezuma died, had lasted only 144 years; and this
calculation is from the most authentic documents known, that is, the
pictures in Purchas’s collection. In Harris’s _Voyages_, vol. ii., p.
97, Montezuma is said to have told Cortez, that it was only a century
since they had been settled where they were, meaning, probably, that
it was not _two_ centuries.
Thus an elephant being found in a tomb in Mexico, and others in tombs
in Siberia, is an additional argument to the strong ones already
produced, for the Mexicans being the Moguls blown from the shores of
Japan, A.D. 1283, which appears irresistible; and also that mammoths
and mastodontes are not extinct, being found either living or fossil
in all the places in America, which agree with the traditions on that
subject, and with the histories of China and Japan[77].
THE TAPIR.
The Tapir was supposed to be peculiar to the New World: two fossil
species, one of them gigantic, have been found in [p361] France,
Germany; and Italy[78]. The remains of a tapir being found at
Florence, with those of other quadrupeds usually exhibited by the
Romans, was an unaccountable fact, till it was known, through Sir
Stamford Raffles, that the tapir exists in Sumatra. We know that the
Romans carried on a commerce with India, which employed _one hundred
and twenty ships annually_, and that they had the power of being
supplied with all the animals of those regions, by means of country
ships, which traded to the ports of Musiris and Barace, those which
the Romans frequented. Moreover, the author of the _Periplus_, p.
36, describes _Sumatra_. It appears, therefore, evident that the
Romans procured tapirs from that island, if they be not inhabitants
of Africa. The British king, father of Caractacus, had a tapir on
one of his numerous coins[79]; which may be reckoned among many
other proofs that the ancient Britons were not quite so ignorant and
barbarous as is generally, but unjustly, imagined. The discovery of
this tapir shows how little is yet known even of those countries in
which Britain has, for a length of years, had establishments. The
tapir is probably what the natives have reported as a _river-horse_,
a much more appropriate name for it than for the African beast. “The
descriptions of the hippopotamus,” says Baron Cuvier, “by Herodotus
and Aristotle, are supposed to have been borrowed from Hecatæus of
Miletus, and must have been taken from two very different animals,
one of which is the true hippopotamus, and the other the _antelope
gnu_ of Gmelin[80].” Now, as it appears that the Indians described by
Herodotus by the name _Padæi_, is an exact account of the _Batta_ in
Sumatra,—(Dr. Leyden thinks them the same word, as the Indo-Chinese
pronounce B as P[81],)—it is rendered probable that that island was
known to the Greeks, long before the Romans possessed Egypt. On these
grounds, I venture a conjecture that Aristotle and Herodotus alluded
to the tapir, which is _amphibious_, but the gnu is not. The tapir
is probably the _küda-ayer_ of Sumatra, and the _conda-aijeer_, or
_river paard_, of the [p362] Javans.—(See MARSDEN’s _Sumatra_, third
edition.) With respect to the _gigantic_ tapir, it is as probable
that those regions (apparently less known to moderns, as regards
zoology, than to the Greeks and Romans) may contain gigantic tapirs
as ouranoutangs, near eight feet high, so lately discovered.
UNICORN.
Many reasons have been given, in another place[82], to prove the
probability of the existence of the unicorn, since which the
following description of two has been met with.
“On the other part of the temple of Mecca are parks or places
enclosed, where are seen two unicorns: they are shown to the people
as a miracle; and not without good reason, for their rareness and
strange nature. One of them, which is much higher than the other,
is not much unlike a colt of thirty months of age: in the forehead
groweth one horn, in manner right forth, of the length of three
cubits. The other is only one year of age, and like a young colt:
the horn of this is of the length of four handfuls. This beast is
of that colour of a horse called weasel, and hath a head like a
hart, but not a long neck, and a thin mane, hanging on one side.
Their legs are thin and slender, like a fawn or hind: the hoofs of
the fore feet are divided in two, much like the feet of a goat:
the outer part of the hinder feet is very full of hair. This beast
seemeth wild or fierce, yet tempereth that fierceness with a certain
comeliness. These unicorns were given to the Sultan of Mecca as a
most precious and rare gift. They were sent him out of Ethiopia by a
king of that country, who was desirous by such a present to gratify
the Sultan[83].”
So lately as the year 1799, a Mahomedan African prince is said to
have sent two of them to Mecca.—(REES’s _Cyclopedia_, “Monoceros.”)
Bell of Antermony describes one which was killed in Siberia, near
the _Irtish_, in 1713. Tamerlane slew unicorns and rhinoceroses on
the frontier of _Cashmere_, (_Sherefeddin_, b. 4., ch. xxx.) and
there have recently been _reports_ of unicorns in _Nepaul_, which are
rendered more probable to be [p363] the truth, by those references
of Mr. Bell and Sherefeddin to countries not very distant.
The British king Cuneboline had also the unicorn on his coins,
and the figure of the animal is very similar to the above
description[84]. The writer is, therefore, of opinion that these now
described are the real oryx mentioned by Aristotle, Pliny, and other
ancient authors[85].
HIPPOPOTAMUS.
The remains of this beast have been found in England at the
residences of the Romans, _viz._, near London, Colchester, and York;
and not any in Ireland or Scotland. They have also been found in
Italy mixed with great numbers of the bones of other beasts known
to have been exhibited by the Romans. This animal is not known to
inhabit any country but Africa. Two were caught near Damietta, A.D.
1600. They are known to inhabit Abyssinia, Bornou, the Cape of Good
Hope, Senegal, and they were met with in great abundance by the two
vessels, the Sion, of 200 tons, and St. John, of 50 tons, which
sailed above nine hundred miles up the river Gambia, A.D. 1620,
employed by Sir Wm. St. John[86]. The inference is, that they inhabit
the whole of that vast continent, and that it is most probable the
number of species is as great as that of elephants; and that the
fossil kinds not having been brought from the same country as the
living individuals with which they have been compared, has induced
naturalists to suppose them extinct. An elaborately grand Roman
[p364] pavement was dug up at Roxby, in Lincolnshire, upon which
is represented Orpheus, surrounded by an elephant, lion, boar, dog,
wolf, stag, and another, which appears to be the hippopotamus[87].
TURTLE. TORTOISE.
“A beautiful fossil sea-turtle has recently been discovered, and,
by the perfect substitution of all the organic parts as well as its
locality, may be considered an interesting remain of a former world.
It is encrusted in a mass of ferruginous limestone, and weighs 180
lbs. The spot on which it was found is in four fathoms of water,
and is formed of an extensive stratum of stones, called the Stone
Ridge, about four miles off Harwich harbour; and is considered to be
the line of conjunction between the opposite cliffs of Walton and
Harwich. It is in the possession of Mr. Deck, of Cambridge[88].”
A fossil turtle was found near Harwich, embedded in a solid block of
cement-stone; another large stone, when broken, was found to contain
“nearly the whole of a _human_ skeleton[89].”
Fossil sea-tortoises have been found in the environs of Brussels, in
the environs of Maestricht, at the village of Melsbroeck and in the
mountain of St. Peter, in the state of Glaris and in the vicinity of
Aix; they differ in species from any of those at present known[90].
There is not any of the extraneous fossil remains more probably of
Roman origin than tortoises. “The beds, the doors, and pillars of the
houses of the Greeks and Romans, were decorated with tortoise-shell.
In the reign of Augustus, this species of luxury was at, its height
in Rome[91]. Bruce says, the Egyptians dealt very largely with the
Romans in this elegant article of commerce; Martial relates that
beds were inlaid with it; Velleius Paterculus observes, that when
Alexandria was taken by Julius Cæsar, the magazines were so full of
this article, that he at first proposed to make it the principal
ornament of his triumph; as he used ivory afterwards when triumphing
for his African victories[92].” [p365]
Cuneboline and his son Arviragus having had the elephant, tapir, and
unicorn on their coins; and as the first was brought up at the court
of Augustus[93], there is every probability of their having possessed
tortoises at Harwich, the port of the capital of the British king.
SPECIES.
With regard to elephants, the number of species appears to be very
great, even with the extremely limited knowledge we possess. The
writer saw three distinct kinds captured in one keddah at Tippera,
when he was there during Mr. Corse’s residence at that place, and who
has described them. Some African females have tusks as large as the
males, but it is not known to be so in Asia. Le Vaillant mentions a
race of elephants which never have tusks. Two Ceylon elephants were
found to differ in the shape of the jaws, and another is mentioned by
Baron Cuvier, which is dissimilar to any that had been seen[94].
The Camelopard now at Paris differs in many essential anatomical
characters from the kind at the Cape of Good Hope[95].
The Romans and Moguls crossed the species and genera of different
animals. The crocotta was between a dog and a wolf; the crocuta,
between a hyæna and a lioness[96]. The Moguls cross the breed of dogs
with leopards, the best of which are those of Hezereh and Tesheen in
Cabulistan; and some are so brave that they will attack a lion[97].
Four towns near Babylon were exempted from any other tax than the
maintaining of dogs which were supposed to be produced between the
tiger and bitch[98]. We thus may perceive how impossible it is to
be certain of a fossil species being extinct because we are not
acquainted with it. [p366]
Ptolemy Philadelphus, in a procession at Alexandria, had twenty-four
thousand Indian dogs, a camelopard, a white bear, and twenty-four
chariots drawn by elephants, twelve by lions, seven by oryxes,
eight by ostriches, four by wild asses, and five by buffaloes[99].
Bajazet, in the fourteenth century, had twelve thousand dog-keepers.
The immensity of wild beasts slaughtered by the Persians, Moguls,
and Romans, would be incredible, were it not attested by so many
different authorities; and with regard to the Romans, no author
mentions a less number than five thousand of every description slain
at the opening of the Coliseum. These sports having been in vogue all
over the Roman empire for so many centuries, the fossil bones which
have been found are but few indeed. In Britain there were at least
five amphitheatres; at Sandwich, Dorchester, Silchester, Caerleon,
York[100]. In France, at Paris, Cahors[101], Vienne, Arles, Orange,
Autun, Treves, Nismes, Poitou[102], and Bordeaux. In Spain, at
Seville, Tarragona, Merida, and Saguntum. In Italy a great number.
The popularity of monarchs and statesmen depended on their power
to indulge the people with these cruel sports. Commodus is said to
have been one of the most dexterous marksmen: he always had with
him Parthians, to teach him archery, and Moors, to perfect him in
throwing the dart. He ran with all horned animals, except bulls,
and smote them unerringly as he pursued. Lions, panthers, and other
fierce beasts, he ran after in the Peridrome, and darted at them from
above with never-failing effect, whether he aimed at the forehead or
the heart. With arrows, pointed like a half-moon, he would cut off
the heads of the Mauritanian ostriches, while their wings were [p367]
expanded to aid their speed, and they continued their course for
a time without their heads. He would expose a prize-fighter to the
attack of a panther, and strike the beast dead before it could fasten
its teeth on the man. A hundred lions have been sent out of the
dens, and all killed by him with such certainty, that they lay close
together, not a dart failing[103].
Domitian had been equally notorious in these grand sports in the
Amphitheatre.
“What scene sequestered, or what rude renown,
Sends no spectator to the imperial town?
The Rhodopean hind now tempts the plains,
And tunes from Hemus his Orphean strains.
The Sarmat, Cæsar, hies, thy works to see;
And gives the steed he swills[104] to share the glee.
They come, who first the rising Nile explore;
And they who hear remotest ocean roar.
The Arab hasted, the Sabean flew;
And the Cilician own’d his native dew.
With tortured tresses, here Sicambrians gay;
There Ethiops, bristling in their diverse way.
’Mid various speech, but one glad voice we find,
That hails thee father of converg’d mankind[105].”
As for the Romans themselves, according to Juvenal, these amusements
seem to have been preferred to all others.
“Could you the pleasures of the Cirque forego,
At Fabrateria or at Frusino,
Some villa might be bought, for what will here
Scarce hire a gloomy dungeon by the year[106].”
Had the fossil animals died, or been killed by natural accidents, the
skeletons would generally have been found entire, but for the most
part they are scattered and broken, and are often mixed with bones
of animals resembling the species of the present time[107]. In the
vicinity of Orleans in France, a _fossil_ roe, of a living species,
was found in _limestone_, along with the bones of the _palæotherium_.
Instances have occurred of bones being found, in great numbers; and,
many feet deeper, other heaps of bones of elephants and wild beasts;
but as many amphitheatres were built [p368] with wood, and as the
games were exhibited for about six centuries, those structures would
require to be often renewed, and the old bones would thus be covered
over with earth. Britain was invaded or visited by about twenty
emperors, or those so high in importance as to become emperors of
Rome; and York was the head-quarters of the Roman empire during the
residence in Britain of Severus and his two sons and co-emperors,
Geta and Caracalla[108]. All the _collections_ of fossil bones
are found at the head-quarters of the Romans, or near the several
amphitheatres in the island. Bones of elephants which have been found
in France and Italy in fifteen places, are so faithfully accurate to
the road over which Hannibal and Asdrubal with fifty-two elephants
marched[109], and _Hannibal’s (thirty-seven) all perished before
his arrival at Thrasymene_, that no theory whatever can stand in
competition with such historical conviction[110]. If the bones found
on Hannibal’s road be not those of his Getulian elephants, are we
to conclude that the remains of the beasts lost two thousand years
ago have totally perished; but that other bones of elephants, many
thousands of years older, have been preserved upon the same spot,
although some of them are found quite near the surface? At Plaine
de Grenelle, a fossil elephant was dug up, and at that place there
stood a Roman amphitheatre[111]. The great numbers of elephants then
used in warfare may be judged of, by Metellus having captured upwards
of a hundred in the battle of Palermo, where many besides had been
killed[112]; and accordingly fossil bones have been found, there
and also at Syracuse, where there was an amphitheatre. In Spain,
thirty-nine elephants were slain at Munda, in the battle fought
between the two Scipios and Asdrubal. At the bridge of Manzanares,
and at Toledo, fossil remains of elephants have been [p369] dug up;
and at these very places Hannibal and Asdrubal defeated one hundred
thousand Carpetani, many of whom were trodden to death by their forty
elephants[113].
If we glance at the sports of the Mongols, what a treasure for an
osteologist might be found at Termed in Sogdiana, where the army
commanded in person by Genghis Khan were four months occupied in
enclosing an immense circle, till all the wild beasts were driven
(without one escaping, under pain of death to the soldier who failed
in his duty, but who was not allowed to kill the tigers, lions, &c.)
into a spacious plain, where they were slaughtered by the Grand Khan
and all the Imperial princes and military commanders, till they
chose to permit the soldiers to end the destruction[114]. How many
fossil _species_ might be discovered there, of which naturalists
have no knowledge! The Persians are said to have slaughtered as many
as fourteen thousand beasts on a like expedition[115]. So long have
these amusements existed, that Hushing, king of Persia, B. C. 865,
_bred dogs and leopards_ for hunting[116].
Besides the fossil remains which have been found of numerous
quadrupeds, named by the Romans in their sports, they employed the
following, bones of which have not been detected:—Indian dogs, white
bears, camels (one found), dromedaries, camelopards, wild asses,
zebras, quaggas, oryxes (unicorns), Ethiopian sheep, Arabian sheep,
the crocotta (bred from a dog and wolf), crocuta (from a hyæna and
lioness), little dragons, ostriches. The gnu was known to the Romans;
and probably the nyl-ghau and the om-kergay (quite harmless, and
the size of a rhinoceros). In this list several of the fossil kinds
described as the ancient wild beast with a thick skin (palæotherium),
and the beast without weapons, or unarmed (anoplotherium), may
be found, and also those of the genus canis, and a carnivorous
beast[117].
Such is a short notice of this most extensive subject, to which the
writer’s attention has been attracted by the concurrence of [p370]
historical relations with the locality of fossil remains. It is
offered for the consideration of the reader, not in a spirit of
controversy, but with a desire to ascertain an important truth in
natural history, whether his speculations be confirmed or refuted.
Whichever way a decision is awarded, it will add to the interest
attached to zoological pursuits, and the reader will be, by these
remarks, enabled to form a judgment whether the laborious and
ingenious works which have been published, since the conviction that
elephants are not human giants, (a notion seriously maintained so
recently as in Clavegero’s _History of Mexico_, written since that of
Robertson) are descriptions of the quadrupeds of a _former world_, or
of the world which is now in _existence_. _It is necessary to remark
that these particular researches relate only to animals connected
with Roman and Mogul history_; and if it should be conceded that it
may justly be inferred, that quadrupeds hitherto deemed extinct are
still to be found in the undiscovered parts of Africa, Asia, and
America, not half of either region being yet scientifically known,
it will give an interest to zoology and osteology ten fold more
attractive than a blank and unsatisfactory hypothesis of their having
all perished _before the creation of man_, as is often alleged. It
is perhaps the most remarkable circumstance in literature, that
naturalists so rarely allude to the astonishing number of beasts
slain in the Roman games, although the list of them is, generally
speaking, so similar to that of the fossil remains. Erroneous notions
concerning fossil bones, those of elephants, in particular, being the
most plentiful, began in very early ages when they were considered
to be human; and James the First (of Britain) sent Lord Herbert
of Cherbury to Gloucester, to ascertain if a skeleton, dug up at
that place, was really that of a giant. There were found mingled
with it horns and bones of oxen and sheep, and the tusks of a boar.
Lord Herbert, Dr. Clayton, and the celebrated Harvey, thought the
bones were those of one of the Roman elephants; and Bishop Hakewill
received a letter from my lord of Gloucester, mentioning that “he was
_not confident_ that the grinder was the tooth of a man[118].” This
discovery, perhaps, put an end in England to the notion of giants’
bones. [p371]
The next fanciful origin was, that these fossil remains were those
of an extinct monster, called Mammoth by the native Siberians, their
name for the walrus; but which was transferred and confounded with
the bones of whales, elephants, and buffalos, found in that country,
and such erroneous opinions will long be entertained in those
quarters.
The diluvian origin was imagined by many to be the true one, but
later careful examinations proving that the animals died on the spot
where they are found broken, and the bones scattered about, that
hypothesis could not in such instances be maintained, and recourse
was had to the supposition, that Britain was in former ages a
tropical country; but the mixed fossil remains, being those both of
hot and cold climates, and of beasts peculiar only to Africa, or to
Asia, this theory appears to be quite as objectionable as the others.
The last, and the most specious, of all the hypothetical proofs of
the origin is, that the teeth not often corresponding with those of
the living specimens which have been seen, they must be the remains
of extinct quadrupeds. There are, perhaps, fifty large regions
where elephants abound, and the teeth of _very few indeed_ of the
animals of those countries have yet been seen. This last appears to
be, defective as it is, the strongest objection that can be urged
against the historical origin; and the few remarks in this essay will
contribute materially to weaken this remaining hypothesis. The reader
who feels any interest in zoology will, by their means, be assisted
in his endeavours to untie or cut this gordian knot. After he has
decided either that these beasts are in existence, or all extinct.
“In his reflections, then, what scenes shall strike!
Adventures thicken! novelties surprise!
What webs of wonder shall unravel there[119]!”
FOOTNOTES:
[53] Count Bournon; Phil. Mag., vol. lvii., p. 458.
[54] Strahlenberg, p. 405.
[55] Dr. Plott’s History of Oxf., p. 161.
[56] Phil. Trans. Abridged, vol. iv., part ii., p. 273.
[57] Cuvier, Theory of the Earth.
[58] In the American Quarterly Review, published at Philadelphia,
March, 1827. Art. “Fossil Remains.”
[59] Titles, “Werner,” “Fletz,” “Transition.”
[60] See two dissertations on the Geology of the U. S. of N.
America, by W. M’Clure, Esq., in the Transactions of the Amer. Phil.
Soc., new series, vol. i., Philadelphia, 1818. This gentleman had
entertained a different view in the previous volume; but after eight
years’ experience, in Europe and America, he had the philosophical
justice, boldly to amend his former opinions.
[61] See Phil. Trans. Abridged, vol. iv., part ii., p. 236 to 245,
and Camden’s Brit., Gough’s Ed., 1789, vol. iii., 604.
[62] Essay on the Antiquity of the Irish Language, by Lieut. Col.
Vallancey, 8vo., London, 1818, p. 12.
[63] See Gibbon, ch. xxvii., Zosimus, b. iv., Rapin, b. i., Wars and
Sports, ch. xiii.
[64] Life of Agricola.
[65] Parkinson, vol. iii., letter 26. Mr. P. relates that Baron
Cuvier inclines to doubt the authenticity of this account; but Capt.
Cochrane’s testimony _now_ renders it very probable to be correct.
It is very worthy of remark, that the wild elephants in America are
found, as reported, at Choco, and west of the Missouri; and that
Mango Capac and Montezuma’s ancestor, by the traditions, landed at
Cape St. Helen’s and Culiacan,—as if some elephants had been let
loose, or had escaped and betaken themselves to perhaps the nearest
thick forests, and have remained there undisturbed.
[66] Rees’s Cyclopedia, Addenda, “Mastodon.”
[67] See Parkinson, vol. iii., letter 26, p. 367.
[68] Duchat, an author of unquestioned credit, has seen recent wood
petrified into flint by the water of a river in Ava. Rees’s Cyc.,
“Wood.”
[69] Levesque, Hist. de Russie, vol. vii. 244.
[70] Wars and Sports, p. 263.
[71] Conquest of Peru, ch. x. It is somewhat curious that, when
Pyrrhus for the first time brought elephants into Italy, the Romans
gave them the name of Lucanian bulls; and that the Americans call
them big bulls in their traditions. It is probable that both people
compared them with the largest beast known to them; as elephants,
if indigenous in america before the arrival of Mango Capac and
Montezuma’s ancestor, would have been extremely numerous, and have
had a proper name.
[72] Shakspeare spells this name Cymbeline; Milton writes Kymbeline,
which is probably the true pronunciation: see his History, 8vo.
1695, p. 62.
[73] Wars and Sports, p. 269.
[74] Id. p. 506. The Burmans eat elephants. The writer was at Dacca
in 1794, when some Burmese troops invaded the Chittagong frontier.
An expedition, under Colonel Erskine, was sent against them; and on
the return to Dacca of Colonel Boujonnar’s battalion, the officers
told the writer that they found in the stockade the skeleton of an
elephant, which the Burmans had devoured.
[75] Conquest of Mexico and Peru, p. 288–301.
[76] Hakluyt, vol. iv., p. 558; and Conquest of Peru and Mexico, ch.
vii.
[77] A Roman coin is said to have been discovered recently among the
Indians in America, which has justly created surprise; but others
have been found long ago. Bishop Hakewill’s book is dated A.D.
1635: he says, “Marianus Siculus, in his history of Spain, reports
that certain coined pieces of gold, engraved with the image and
inscription of Augustus Cæsar, were found in the American mines;
thereby inferring that those countries were _then_ discovered.” p.
310. Batou, the cousin of Kublai, both grandsons of Genghis, had
conquered Russia, ravaged Europe to the Adriatic, and died on his
march to Constantinople, in 1256. His successor also ravaged as far
as Constantinople, (P. de la Croix, p. 387.) Mango (so spelt by Du
Halde, ii., 251, and Maundeville, p. 275; Manku by Tooke, Russ.
Emp., ii., 13) was brother to Kublai, who is considered by the
writer to be the father of the first Inca, and there is nothing more
probable than that he and other Moguls on the Japanese expedition
may have possessed Roman coins, the plunder of Hungary, Poland,
Dalmatia, and the Greek empire, as far as the capital.
[78] Cuvier, Theory of the Earth, p. 257.
[79] Conq. of Peru, &c. plate iv.
[80] Theory of the Earth, p. 67.
[81] Herodotus, Thalia xcix. Rees’s Cyc., “Sumatra.”
[82] Wars and Sports, p. 335.
[83] Travels of Lewis Vertomanus to Egypt, Arabia, &c., A.D. 1503,
in Galvano’s collection. Hakluyt, vol, iv., p. 162.
[84] Wars and Sports, p. 354.
[85] See Cuvier’s Theory of the Earth, p. 80. Wars and Sports, p.
335. With regard to the unicorn, Camper has remarked, that “if
this animal was ruminant and cloven-footed, it is certain that its
frontal bone must have been divided longitudinally into two, and
that it could not possibly have had a horn placed upon the suture.”
This remark by Camper, when we consider how nature adapts every
thing to its purposes, cannot stand as a real objection to the
existence of the oryx. The most eminent naturalists have been wrong
in some of their conjectures. John Hunter pronounced the mastodon
to be a carnivorous beast. Buffon, after frequently considering the
bones of the mammoth, conceived them to belong to a beast six times
larger than the biggest elephant; and Muller was of opinion that
it must have been 105 feet in height, and 133 in length! So little
capable is any human being to judge what nature does, or can do!
[86] See Relation of Master Wm. Jobson in Purchas, vol. ii, p. 921.
[87] Conq. of Peru; p. 450.
[88] New London Literary Gazette, Oct. 13, 1827, p. 303.
[89] Common Sense Newspaper, No. 60.
[90] Cuvier’s Theory of the Earth, p. 291.
[91] Shaw’s Zool., III. pt. 1. Rees’s Cyc. “Tortoise.”
[92] _Ibid._
[93] Milton’s Hist. 8vo. p. 62.
[94] Cuvier, Ossemens Fossiles, p. 185.
[95] Ed. New Phil. Journal, Sept. 1827, p. 390. Here is a direct
instance, that if a fossil _Egyptian_ camelopard had been found, it
would, like elephants, &c., have been pronounced to be an _extinct_
species, the modern specimens being from South Africa.
[96] Pliny, b. viii.
[97] Ayeen Akbery, vol. i. p. 242.
[98] Herodotus, Clio, cxci. We may conjecture that _tiger_ has been
written for _leopard_, a frequent error.
[99] Montfaucon, vol. iii. p. 179.
[100] Augustan History, “Severus,” p. 253. “Wherever Caracalla
wintered, or but intended to winter, they were constrained to erect
amphitheatres and cirques for public games, and those within a
while were taken down again.”—Hakewill’s Apology, p. 443. Caracalla
was three years at York; and Spartian, in his Life of Severus,
relates, that among other omens just before that emperor died, (at
York,) three figures of Victory, which stood upon the platform near
the throne, were blown down while the _games of the circus were
celebrating_. There was a Roman road from York to Whitby (Dunus
Sinus), and Kirkdale is about half way between the port and the
capital.
[101] Rees’s Cyc. “Cahors.”
[102] Marquis Maffei, p. 260.
[103] Herodian, “Commodus.”
[104] The Tartar opens a vein of his horse and drinks the blood.
[105] Martial (Elphinston’s, p. 19) on the Sports of Domitian.
[106] Satire iii.
[107] Cuvier. Theory of the Earth, pp. 89 and 263.
[108] The emperors had their families and the whole Roman court with
them. The celebrated Julia Domna, and her sister Julia Mesa, were
there during those three years. See De Serviez, Roman Empresses,
vol. ii. p. 239.
[109] Passage des Alpes par Annibal, d’après la narration de Polybe.
Comparée aux récherches faites sur les lieux, par J. A. De Luc.
Géneve, 1818.
[110] Wars and Sports, p. 295.
[111] Gibbon, ch. xix. p. 177.
[112] Catrou, vol. ii. p. 591.
[113] Livy, b. xxi. ch. v.; b. xxiv. ch. xlii.
[114] De la Croix. Hist. of Genghis, b. iii. ch. vii.
[115] Sir John Chardin, vol. ii. 33.
[116] Sir William Jones, vol. v. 588. The above may possibly mean a
cross breed of the two beasts, which we find is still practised in
Cabulistan, as related in the Ayeen Akbery.
[117] See Rees’s Cyc. “Strata.”
[118] Hakewill’s Apology, p. 229.
[119] Young. Night VI.
_Description of a cheap and portable Instrument for enabling Young
People to acquire a knowledge of the Stars, or determine their
situation in the Heavens_. By S. Lee, Esq.
There is no science, the study of which tends so much to enlarge the
mind as Astronomy. It opens to our view the grandest examples of
Almighty power, wisdom, and beneficence—the [p372] contemplation
of which fills the soul with reverence and affection for the great
Author of nature, and banishes all narrow and superstitious notions
respecting him.
The cultivation of this science, therefore, cannot be too strongly
recommended to the attention of young people. The eager curiosity
and avidity for discovery which so peculiarly distinguish that
period of life, when the reasoning faculties begin to develope, is
peculiarly fitted for its reception—and, accordingly, amongst the
better-educated classes of society, the elements of this science are
generally considered as a necessary branch of instruction—though
commonly limited to a mere _dogmatic_ explanation of the Copernican
system, and the use of the globes.
But this superficial mode of instruction, though sufficient to enable
any one to understand the real motions of our planetary system, and
explain the apparent motions which must result from them, is hardly
sufficient to satisfy inquisitive reasoning minds, since it leaves
them ignorant of the means by which the distances, magnitudes, and
orbits of the planets and comets were first discovered; and how, if
lost, a knowledge of them might be recovered from observations alone.
The most pleasing methods of instruction will generally be found the
most efficient. It is impossible for any one who has had the least
experience in teaching not to have perceived, that one practical
application of science makes a deeper and more lasting impression on
the mind of a learner than a thousand theoretic propositions.
An accurate knowledge of the fixed stars is the first step to
practical astronomy; it is, in fact, the alphabet of the science. By
the rising, southing, and setting of these bodies, astronomers are
enabled correctly to measure time; and from their apparent altitudes,
to determine the latitude of places on the surface of the globe,
whilst the permanent situations which they maintain with respect to
one another, furnish them with so many marks by which to trace the
course of the sun, moon, and planets through the heavens. Such were
the data which enabled Copernicus and Newton to unravel the seeming
irregularity of their apparent paths, and explain the beautiful
simplicity of their real motions.
The instruments usually had recourse to for this purpose [p373] are,
celestial globes, planispheres, and atlases, but none of these afford
such ready and certain means of finding or identifying particular
fixed stars, as at first might be expected from them.
The Globe possesses the great advantage of being easily rectified
to the place of observation and adjusted to the exact hour of the
night. It likewise exhibits all the stars in their proper situations
of altitude and azimuth;—but the constellations being delineated
on a convex surface, and viewed from without, whilst the heavens
appear to us a concave viewed from within, the groups of stars are
seen reversed, a circumstance which, occasions no small degree of
perplexity to a learner.
Planispheres and atlases exhibit the constellations as they appear to
the eye when on the meridian, but in a position very different from
that which they assume when removed far from it. In short, except the
pleiades and a few remarkable groups, it is difficult to recognise a
constellation in every position, without great practice and continued
observation.
The Equatorial furnishes the best and readiest means of discovering
or identifying any particular star, but the great price of this
instrument, and the complicated nature of its adjustments, render it
unfit for learners.
The instrument which we are about to describe, is in its principle
the same as the Equatorial, though not pretending to any thing like
the same degree of accuracy; but it has this advantage over it,—its
adjustments are more simple and obvious, consequently, better adapted
to the capacity of learners; and it can be afforded at a very
moderate expense, the price not exceeding that of a common globe.
A, B, C, D, is the stand of the instrument, composed of three
triangular pieces of wood glewed together, so that the plane of the
upper piece, D B C, makes with that of the lower piece, A B C, an
angle equal to the co-latitude of the place it is intended for.
On the upper piece, D B C, is described a circle, E F G, the
circumference of which is divided into twenty-four hours, and every
hour into twelve parts, equal to five minutes each.
From the centre of this circle, and perpendicular to the [p374]
plane on which it is described, rises a pillar, the top of which
appears at H above the cone I, which can be made to revolve upon it
as an axis.—On the surface of the cone is delineated the principal
stars visible in England, and the lower edge is divided into 365
parts, representing the days of the year.
[Illustration]
On the top of the pillar is fitted a segment of a circle, K, of
[p375] about 140°: viz. 90° of north, and 40° of south declination,
which may be made to revolve upon the pillar as an axis independently
of the cone. To this part is attached the scale, L, divided into
degrees of north and south declination, corresponding to those on the
semicircle,—and so contrived as in every situation to touch lightly
the surface of the cone.
To the declination circle K is attached the alidade M, which may be
set to any degree required, and serves as an index to direct the eye
of the observer to any object, which may be viewed along the edge of
it, or through the small holes in the sights O P.
Having described the several parts of the instrument, it only remains
to shew the use of it; which will be best explained by means of a few
problems.
PROBLEM 1. To adjust the instrument.
The instrument being made for the place of observation, need only
to be placed on a perfectly horizontal stand, and with the line
joining the hours XII and XII on the circle, in the direction of the
meridian: the former of these adjustments may be verified by means of
a small level applied to the stand at N, in the directions B C and A
N successively. If found incorrect in either position, let a piece
of card be put under that foot (A, B, or C) from which the bubble is
found to recede, and let this operation be repeated until the bubble
rests in the middle, in both positions.
The instrument may be brought into the meridian by the assistance of
a magnetic needle fixed to the frame at N, or on the opposite side,
or more correctly by means of the sun, provided the time be exactly
known, thus:—
Set the index M to the sun’s declination, turn the circle K round
its axis, till the scale L points to the hour and minute on the
circle E F G. Then if the instrument be correctly placed, the sun
will be seen through the sights O, P, or what is the same thing, the
light admitted at the hole O will fall on the hole P. If not, the
instrument must be turned about till this effect is produced.
The instrument being once carefully adjusted to the meridian on any
immoveable stand, such as the sill of a window, [p376] the top of
a post, &c., lines may be drawn on the stand in the direction of
the sides A B, A C, or B C, by means of which it may at any time be
replaced with little trouble.
PROBLEM 2. The instrument being correctly placed and levelled, the
next operation will be to adjust the conical projection to the day
and hour of observation.
Turn the cone round till the day of the month on the circle, at the
bottom of it, coincides with the hour and minute on the circle E F G.
Example.—To adjust the cone for the 15th January, at twenty minutes
past nine at night. Turn the cone till the 15th January on the circle
attached to it coincides with IX h. 20 m. P. M. on the circle E F G.
PROBLEM 3. The cone being adjusted, and any star proposed, to find
its place in the heavens.
The cone remaining at rest, turn the declination segment K till
the scale L cuts the proposed star on the projection; note its
declination on the scale and set the index M to the same degree on
the segment K, when the index will point to the star, which, if the
adjustments have all been correctly made, will be seen through the
sights P, O.
Example.—To find the star Aldebaran; look for Aldebaran on the
projection, bring the scale L to cut it, and you will find it against
16° north declination. Set index M to 16° N. P., and look along the
edge of it, or through the holes P, O, and you will see the star.
PROBLEM 4. Having observed a star in the heavens, to find it on the
projection.
Set the cone as accurately as you can to the day and hour, then turn
the declination segment round, and elevate the index till you can see
the star through the sights P, O. Note the declination at the segment
K, cut by the index M, and against the corresponding degree of the
scale you will find the star on the projection.
If no such star can be found, you may then conclude that it is a
planet, or a new star.
By this means the place of the moon, of a planet, or a comet, may be
noted down, from time to time, and their apparent paths traced out.
[p377]
PROBLEM 5. To find the hour of the day by the sun.
Turn the segment K, and elevate the index M, till the sun is seen or
shines through the sights O, P, and the scale L point to the hour and
minute on the circle E F G.
PROBLEM 6. To find the hour of the night by means of a star.
Direct the index M to the star, so as to be seen through the sights
P, O; then laying hold of the scale L, to keep it in that position,
turn the cone till the star on the projection is cut by the scale,
when the day of the month on the circle at the bottom of the cone
will coincide with the hour and minute on the circle E F G.
This instrument, though not capable of extreme accuracy, might, by
means of careful workmanship, and the addition of a small telescope,
be made sufficiently so for finding stars in the day time; but such a
one as that now described will answer all the purposes of a learner,
and enable very young people to acquire a correct and extensive
knowledge of the stars in a very short time.
The surface of a cone has been adopted for the projection, in
preference to that of a globe or planisphere, having been found,
after repeated trials, the figure best suited to the nature of the
instrument.
_An Introduction to the Comparative Anatomy of Animals, compiled
with constant reference to Physiology, and elucidated by twenty
copper-plates_. By C. J. Carus, M.D., &c. Translated from the
German, by R. T. Gore, Member of the Royal College of Surgeons in
London.
If we except Sir Everard Home’s splendid work on comparative anatomy,
we have no original treatise on that subject which deserves notice;
and even Sir Everard’s lectures must rather be considered as a series
of essays on detached parts of that branch of science, than as a
regular and systematic view of it. We have long been acquainted with
the work of Dr. Carus, and have always considered it as a laborious
and accurate epitome of the principal facts and authorities in the
study to which it relates. From the immense field of inquiry which it
embraces, it is necessarily complicated, and [p378] in some places
a little obscure, but it is entirely free from those speculative
and hypothetical wanderings which are too characteristic of the
German school of physiology; and though it contains some systematic
notions in which we cannot acquiesce, and a few new words, not the
most harmonious in the world, it may very safely and properly be
recommended to the student as a text-book, and to the proficient as
a work of reference. The plates by which it is illustrated are upon
an economical scale, sometimes rather too small to be distinct, but
they are otherwise accurate and carefully drawn; and we are aware
that it is impossible to obviate these objections without incurring
such expense as would probably render the work inaccessible to those
readers for whom it is principally compiled.
Mr. Gore has assiduously and faithfully executed the difficult task
of translation, and has added no inconsiderable quantity of new and
important matter in the form of notes, rendering the English work
more complete, and upon many points much more satisfactory than the
original.
_Experiments to determine the Comparative Value of the principal
varieties of Fuel used in the United States, and also in Europe,
and on the ordinary Apparatus used for their Combustion_. By Marcus
Bull. Philadelphia and London, 1827.
The population of London and its immediate environs may be estimated
at about two millions, and the annual consumption of coals within the
same district does not fall far short of two millions of chaldrons,
or seventy-two millions of bushels. Of this prodigious quantity of
inflammable matter, a very considerable portion escapes combustion,
and lodges in the form of soot in our chimneys, or is vomited forth
to contaminate and cloud the atmosphere of the metropolis: so great
is this loss, that independent of the mere advantage of getting rid
of smoke, its prevention is an important economical problem; and
though the rage for smoke-burning has passed over, we are quite
certain that the subject still deserves the most serious attention,
being convinced that, of the fuel consumed in the ordinary processes
of warming our houses and cooking food, at least one-third is
uselessly thrown away, and might be saved by a more economical and
scientific construction of common grates and fire-places. All useful
and well-conducted experiments, therefore, in [p379] relation to
these matters, deserve notice; and though much of Mr. Bull’s essay
is not applicable to our case, it contains a variety of interesting
facts and information: his experiments appear to have been very
carefully conducted, and should be consulted by all those who are
engaged in similar investigations.
_Meteorological Essays and Observations_. By J. Frederic Daniell,
Esq., F.R.S. Second Part, 1827.
We hope to be able in our next Number to enter into a detailed
examination of the subject of Mr. Daniell’s inquiries; at present,
therefore, our object is merely to announce the second edition of his
valuable and laborious essays, and the publication of the present
_second part_, in which, for the convenience of those who possess
the former edition, all the new matter is collected. It includes the
following essays:—
1. On the Trade winds, considered with reference to Mr. Daniell’s
theory of the constitution of the atmosphere; in a letter from Capt.
Basil Hall, R.N., F.R.S.
2. On evaporation as connected with atmospheric phenomena.
3. On climate, considered with regard to horticulture.
4. On the oscillations of the barometer.
5. On the gradual deterioration of barometers, and the means of
preventing the same.
6. Addenda and notes—among which will be found a valuable table of
the elastic force of aqueous vapour, calculated by Mr. Galbraith from
the experiments of Dr. Ure, by the formula of Mr. Ivory.
_Philosophical Transactions of the Royal Society of London, for the
year 1827_. Part II.
The following are the contents of this Part of the Society’s
Transactions:—
On a new form of the differential thermometer, with some of its
applications. By William Ritchie, A.M., rector of Tain Academy.
Communicated by J. F. W. Herschel, Esq., Sec. R.S.
On the structure and use of the submaxillary odoriferous gland
in the genus Crocodilus. By Thomas Bell, Esq., F.L. and G.S.S.
Communicated by Sir Everard Home, Bart, V.P.R.S.
On the permeability of transparent screens of extreme tenuity of
radiant heat. By William Ritchie, A.M., rector of Tain Academy.
Communicated by J. F. W. Herschel, Esq., Sec. R.S. [p380]
On the derangement of certain transit instruments by the effects of
temperature. By Robert Woodhouse, A.M., F.R.S., &c.
On some of the compounds of chromium. By Thomas Thomson, M.D.,
F.R.S. L. and E., Professor of Chemistry, Glasgow.
Rules and principles for determining the dispersive ratio of
glass; and for computing the radii of curvature for achromatic
object-glasses, submitted to the test of experiment. By Peter
Barlow, Esq., F.R.S., Mem. Imp. Ac. Petrop, &c.
On the change in the plumage of some hen-pheasants. By William
Yarrell, Esq., F.L.S. Communicated by William Morgan, Esq., F.R.S.
On the secondary deflections produced in a magnetised needle by an
iron-shell, in consequence of an unequal distribution of magnetism
in its two branches. First noticed by Captain J. P. Wilson, of the
Honourable East India Company’s ship Hythe. By Peter Barlow, Esq.,
F.R.S., Mem. Imp. Sc. Petrop.
On the difference of meridians of the royal observatories of
Greenwich and Paris. By Thomas Henderson, Esq. Communicated by J. F.
W. Herschel, Esq., Sec. R.S.
Some observations on the effects of dividing the nerves of the
lungs, and subjecting the latter to the influence of voltaic
electricity. By A. P. W. Philip, M.D., F.R.S. L. and E.
On the effects produced upon the air-cells of the lungs when the
pulmonary circulation is too much increased. By Sir Everard Home,
Bart., V.P.R.S.
Theory of the diurnal variation of the magnetic-needle, illustrated
by experiments. By S. H. Christie, Esq., M.A., F.R.S.
On the ultimate composition of simple alimentary substances; with
some preliminary remarks on the analysis of organized bodies in
general. By William Prout, M.D., F.R.S.
_A Practical Treatise on the use of the Blowpipe in chemical and
mineral analysis; including a systematic arrangement of simple
minerals, adapted to aid the student in his progress in mineralogy,
by facilitating the discovery of the names of species_. By John
Griffin, Author of Chemical Recreations. Glasgow, 1827.
Performing with the blowpipe is something like playing upon the
fiddle—it looks mighty easy, but for its perfect accomplishment
requires a combination of skill and dexterity which practice alone
can confer. We are disposed, therefore, to think lightly of those
essays upon the subject which pretend to instruct the beginner in
the actual use of the instrument; telling him how he is to puff out
his cheeks, breathe through his nose, make a valve of his tongue,
and keep up a [p381] perpetual stream through the nozzle of the
tube; all which is much easier described than done, and is entirely
matter of experimental acquisition, more easily attained without
than with the usual instructions. In the little work before us, all
these matters are passed over with fit brevity, and the attention of
the student is chiefly directed to the appearances which different
substances exhibit before the blowpipe, and by which minerals may
be distinguished and classed. The history of these constitute the
bulk of Mr. Griffin’s duodecimo, being preceded only by a few
remarks upon the different kinds of blowpipe, respecting which we
have merely to observe that justice is not done to Mr. Newman, who
first suggested what is here called “Dr. Clarke’s blowpipe;” indeed
elsewhere the author seems a little angry with Mr. Children for
recommending Mr. Newman’s apparatus. We observe, moreover, that no
notice is taken of Mr. Newman’s and several other papers on the
blowpipe, which have appeared in the old series of this Journal; nor
of Dr. Clarke’s original Essay, published in the second volume of
that work, from which, and sundry other symptoms, we conclude that
Mr. Griffin is a pupil of Dr. Thomas Thomson. Be this as it may, we
bear him no malice, and very conscientiously recommend his book to
the mineralogical student, as a valuable and clear epitome of what
relates to the behaviour of substances before the blowpipe.
_Circle of the Seasons, and Perpetual Key to the Calendar and
Almanack; to which is added the Circle of the Hours and History
of the Days of the Week, being a compendious Illustration of the
History, Antiquities, and Natural Phenomena of each Day in the
Year_. London, 1828. Small 8vo.
The title of this book may lead our readers to suspect it as an
interloper among works on science; but it touches upon many points of
scientific inquiry, and upon botany especially, and is compiled with
so much evident labour and accuracy, as to merit recommendation. The
saints and festivals of each day are recorded, by which we make the
acquaintance of many worthy persons and curious anecdotes; there is
also a brief natural history of each day, containing short notices
of the plants which on an average begin to flower or to fade, and
of the birds which arrive or begin to sing. [p382] The merits of
the descriptive poetry, which is thickly interspersed, we leave to
other critics. Those who are destined to live in the “fuliginous
tenebrosity” of this smoke-saturated metropolis, and to breathe an
atmosphere “sated with exhalations rank and fell,” care little about
the first peeping forth of the modest snowdrop, or the early bursting
of the golden crocus; but such as reside in the country will be
glad to have their attention pleasingly directed to the successive
products of the field, the flower-garden, and the green-house.
_Conversations on the Animal Economy_. By a Physician. 2 vols. small
8vo. London, 1827.
We have more than once expressed our opinion on the subject of
conveying information to young people in the way of “Conversations,”
which in the present volumes are carried on between Dr. A., Harriet,
Sophia, and Charles; they are at once instructive and amusing, and
evidently the produce of one possessed of much information upon the
subjects discussed, and, what is more to the point, of the art of
pleasantly and intelligibly conveying it.
The Conversations open with an account of the coverings or
integuments of animals; their arrangements by systematic writers are
then adverted to, and a short but useful description is given of the
varieties of mankind, as enumerated by Blumenbach and illustrated
by Camper. The bones and muscles form the subjects of the fifth
and sixth conversations; they are concisely described, and with
sufficient accuracy. The brain and nervous system and the organs of
sense are next talked about. The doctrines of phrenology are fairly
explained; and in the conversations on smell and taste, vision,
hearing, and touch, the anatomy of the respective organs, and their
varieties in the different animal tribes are treated of, the dulness
of the details being relieved by physiological illustrations. The
remaining conversations are occupied with an account of the principal
functions of animals, and of the several organs chiefly concerned
in their performance; the varieties of teeth and stomachs are here
treated of, and the structures of the heart and blood-vessels, as
concerned in circulation and respiration. The production of heat by
animal systems is then noticed; and the twentieth and concluding
conversation is employed in the exposition of the general phenomena
of growth and decay. [p383]
We have thus briefly stated the contents of these volumes, which
are further illustrated by numerous woodcuts and several plates;
and are perfectly ready to commend the performance as an extremely
useful and proper book for young persons, but _not_, in our opinion,
of both sexes: we should have been better pleased if Harriet and
Sophy had been replaced by William and Thomas; for we cannot fancy
the subjects here discussed as quite fit for young ladies. Boys, on
the contrary, ought to know much more of these matters than they
commonly do; and for conveying such information in a pleasing and
familiar, yet neither vulgar nor superficial style, this compilation
seems perfectly appropriate, and will, we trust, find, as it ought, a
numerous class of readers.
_Notice of a New Genus of Plants discovered in the Rocky Mountains
of North America by_ Mr. David Douglas. By John Lindley, Esq.,
F.L.S., &c. &c.
Upon his journey across the rocky mountains in April 1827, in
latitude 52° N., longitude 118° W., at an estimated elevation of
12,000 feet above the level of the sea, the attention of Mr. Douglas
was attracted by a brilliant purple patch amidst the surrounding
snow. On approaching it, he was surprised to find that the colour
which had arrested his eye was caused by the blossoms of a little
plant, from which the superincumbent snow had not yet melted away.
The well-known Saxifraga oppositifolia immediately occurred to his
recollection, and he at first imagined he had either discovered that
species, or one nearly allied to it; but upon a closer inspection,
he perceived that it was no Saxifraga, but a genus apparently new.
Specimens having been submitted to me for examination since Mr.
Douglas’s return, the following description has been drawn up:—
The plant forms a thick tuft consisting of numerous perennial
branched stems, the lower of which are covered with the persistent
decayed leaves and fruit of previous summers. The _stems_ are round,
bright purplish brown, covered with scattered, rigid, branched,
short hairs, and densely clothed with opposite spreading leaves.
The leaves are a dull glaucous green, semi-amplexicaul, [p384]
linear, obtuse, about five lines long and three-quarters of a line
broad, so closely covered with hairs like those of the stem, that
the whole epidermis is hidden. Their veins are concealed by the
hairs; but if the latter are removed, they appear to consist of a
thickened mid-rib, and a few nearly simple spreading venæ primariæ.
The _flowers_ proceed from the axillæ of the upper leaves, from
three to six on each little branch; at first they are sessile, but
their foot-stalks subsequently lengthen by degrees until the fruit
is ripe, when they are from three-quarters of an inch to one inch in
length, and covered with the same sort of hairs as the leaves and
stem. The _calyx_ is hairy in like manner, obconical, angular, with
five equal erect narrowly triangular teeth, about the length of the
tube. The _corolla_ is of a vivid purple colour, infundibuliform,
wholly destitute of pubescence; the _tube_ is a little ventricose
and rather longer than the calyx, its whole length being about three
lines; the _limb_ is spreading, five-parted with cuneate, oblong,
obtuse, segments; the orifice is guarded by five transversely linear
calli, placed under each sinus, and corresponding to the same number
of external depressions of the neck of the tube. The _anthers_ are
linear oblong, nearly sessile, opposite the segments of the corolla,
and a little enclosed within the tube. The _ovarium_ is superior, of
an obovate figure, one-celled, with a central, free, fungilliform
placenta, the lower edge of which has five teeth corresponding to an
equal number of peltate ovula; the _style_ is filiform, as long as
the tube of the corolla, and continuous with the ovarium; _stigma_,
a minute depressed cup. The _capsule_ is of a cartilaginous texture,
surrounded by the persistent calyx; one-celled, with five recurving
valves; the _seeds_ are two, peltate, oblong, convex on the outside,
concave in the inside, dark brown, covered closely with minute
dots or depressions; four only having been found, their internal
organization has not been determined.
Hence it appears that, with the exception of the interior of the
seed, the whole structure of the plant is determinable: it is also
obvious that it is referable to Primulaceæ, of which it possesses
all the characters. In fact it is closely akin both to Primula and
Androsace. From both these genera, however, [p385] its ovarium which
exhibits the greatest instance of reduction of ovula yet known in the
order, and its dispermous capsule, with oblong concave seeds, readily
and essentially distinguish it.
I have, therefore, named it after its indefatigable discoverer,
whose active and successful researches in its native country, richly
entitle him to the distinction.
DOUGLASIA.
NAT. ORD. _Primulaceæ_; _inter_ Primulam _et_ Androsacen.
_Calyx_ obconicus, angulatus, 5-dentatus. _Corolla_ infundibularis,
tubo ventricoso, limbo plano 5-partito, fauce callo lineari sub
utroque sinu. _Ovarium_ uniloculare placentâ centrali liberâ
pedicellatâ fungilliformi, margine 5-dentato; ovula 5 dentibus
placentæ opposita. _Capsula_ vestita, unilocularis, 5-valvis.
_Semina_ duo concava scrobiculata.—Cæspes _suffruticulosus_ (Americæ
borealis), foliis _indivisis_, pube _rigidâramosâ_, _floribus
axillaribus solitariis_.
Sp. 1. _Douglasia nivalis_.
_A Description of the Aurora Borealis seen in London on the Evening
and Night of the 25th of September, 1827; with Critical Remarks upon
other Descriptions of the same, and previous Appearances of the
Meteor, both in the Northern and Southern Hemispheres_. By E. A.
Kendall, Esq., F.S.A.
On the evening and right of the 25th of September last, the horizon
of the metropolis, toward the north, and toward the north-west and
the north-east, exhibited a remarkable display of the meteor or
phenomenon called, after the example of the Italian philosopher
Gassendi, Aurora Borealis.
The weather, for many days preceding, had been mild, with alternate
sunshine, clouds, and showers. The wind had been generally in the
west and south-west quarters; though on the 18th and 19th it was in
the north-west, and on the 20th in the north-east. The barometer,
at three o’clock in the afternoon, had stood at from 30° 40′ to 30°
20′, to which latter height it had descended on the 20th; and, from
that day to the 25th, it had remained, at 29° 90′ and 29° 75′. The
thermometer, at the same hour, between the 14th and the 20th, had
ranged between 65° 6′ and 59° 2′; and it stood, on the 25th, at 59°
6′, with the wind in the south-west. The sky, toward the zenith, on
the evening of that day, was [p386] partially clear, and partially
covered with shifting clouds. On the north, and on the west and east
of north, heavy and stationary clouds blackened the whole horizon, to
an elevation of more than five degrees; and the southern hemisphere
was dark with dark clouds from the horizon to the zenith.
* * * * *
I. By some, the Aurora was seen from the time when the sun was
set; but the first appearance in the heavens, which attracted the
attention of the present writer, whose situation at the moment shut
out from him the horizon upon all sides but the west, was that of a
certain breadth of red or copper-coloured light, or of light of a
colour nearly resembling that reflected by an ordinary conflagration
of buildings, pointing upward from the west. The colour, indeed,
was dissimilar from that which is usual upon the occurrence of a
fire on a cloudy night; yet, in the absence of any other immediate
explanation, he should not have hesitated so to understand it,
except for the figure within which it was circumscribed, and which,
instead of being diffusive, and less and less conspicuous toward
its extremities, or rounded in its outline, like masses of ruddy
smoke, had the peculiarities of an equal breadth, rectilinear
sides, a square top, and sharp outlines. Its height was continually
increasing; but not even that phenomenon, nor even the curve to the
eastward, across the heavens, and which it presently began to add to
its figure, were appearances absolutely to dissipate the illusion of
the existence of a fire; and it was scarcely, therefore, till this
breadth of colour, throwing itself entirely over the heavens, and
descending, at its projected extremity, toward the east, formed an
arch, of which, perhaps, the elevation was seventy degrees, (which
was not the work of many minutes, the motion, at the same time, being
visible, but of moderate rapidity,) that its real character of a
natural phenomenon distinctly impressed itself upon the mind of the
present writer, its observer. While this, however, was proceeding,
the road which he was pursuing had brought him more into view of
the north-western and northern horizon; and, then, the light in the
north, and to the west of north, which, from behind the clouds that
lined the horizon, seemed like the light of a rising moon, or of
the [p387] breaking day, together with the vertical projection of
rays of light, beneath and above the arch, removed every doubt as to
the cause of the appearance, by demonstrating its connexion with an
Aurora Borealis.
It was now about a quarter past eleven o’clock. The sky, beneath
the lower or inner edge of the arch, was clear and star-light, and,
through the contrast created by the ruddy colour placed against
it, appeared of a lively blue. The upper edge of the arch, in the
meantime, was relieved only by the dark gray of the clouds, which,
with more or less continuity, overhung the upper part of the heavens.
But these latter were now dispersing; the cloudless zenith, which
presently afterwards disclosed itself, was now progressively and
swiftly preparing; and, as the clouds moved and fled, the outlines of
the arch lost their sharpness, the colour changed, from that of fire
or of copper, to something more or less of purple or of the rose; it
spread itself in the vapour, and with the vapour vanished.
* * * * *
II. But this was only the curtain of the stage, behind the folds of
which the true scene had its existence. This latter, still concealed,
to a certain and uniform height, by a parapet, as it were, of dark
and unbroken clouds, consisted, first, in the ground of white light,
already described as resembling that of a sky in the midst of which
clouds shut out the disk of the moon, or rather that in which the
rising sun is just about to appear; and, secondly, in a range of
columns, or fountains, or jets of light, more coloured than the
ground, which, rising from behind the ridge or parapet of clouds, and
from and in the midst of the white light, formed, together, not the
figure which would have been produced by their uniform convergence
toward the zenith, but one which bore some resemblance to that
assumed by the sticks of a fan, or still more to the appearance
of stalks in a flower-basket, or in a sheaf of corn. For, in this
manner, the column, which, in general terms, may be called the
central one, and which arose in the due north, was vertical, and
therefore projected toward the zenith; while those which extended
from it upon either side, that is, toward the west or toward the
east, gradually inclined more and more [p388] toward the horizon on
their respective sides; and, as to the outer columns on the east,
inclined, not in rectilinear figures, but in curves more or less
decided. In these columns or coruscations several particulars were to
be remarked.
1. That, within the space of from one hour to two, the whole group
appeared to traverse the horizon together, from the west of north to
the east of north, as if upon one movable base, or as if the source
of their appearance became gradually exhausted to the west of north,
and grew gradually into activity upon the east of north; alternatives
of explanation, however, which might materially affect the theory of
their production. During the whole change, in the meantime, the north
preserved its splendour, appearing uniformly as the focus of the
fire, or as the pivot of the machine, or as the well from which all
else was supplied. The change consisted in the appearance of columns,
of more or less magnitude, strength, and brightness, more or less
advanced from the north toward the west, or from the north toward the
east; but the north, during all this variation, suffered no other
change than this, that whereas, in the beginning of the evening, the
greater portion of columns rose to its west, while, in the latter
part of the night, the greater portion arose to its east. But,
besides this general configuration, and this united motion of the
meteor, there was to be observed, in the several columns themselves,
both the variations of colour which distinguished one from another,
and the irregular and independent movement of each, always in the
direction of its length or altitude, and situate in the interior,
as it were, of its body; and also that peculiarity of form which
distinguishes these coruscations from all other luminous appearances.
2. The colours of the columns, in that part of their height which
is nearest their base, and where, as a ground, they had only the
white light of the horizon, by which, and by their motion, and it
should, perhaps, be added, their vividness, they were distinguished,
is a point upon which the writer speaks with some hesitation, and
with respect to the more close observation of which he could like
to enjoy a second opportunity of beholding the phenomenon. The
variety and richness, and sometimes the terrible grandeur, of the
colours [p389] exhibited in the Aurora Borealis, is the constant
theme of spectators and naturalists; and, upon the late occasion,
an observer, apparently of more regularly scientific habits of
pursuit than himself[120], has particularly insisted upon a column,
of a violet colour, rising west of north, and the place of which he
thinks corresponding with that of the _magnetic pole_; a coincidence
from which, as it may seem, he would believe a confirmation of the
_magnetic theory_ of the production of the Aurora to be obtained.
In setting down the present description, the writer tasks himself
to the most faithful description of what he actually saw, and
suppression of all desire to support or condemn a theory, of which
his mind is capable; and by those rules, therefore, the whole
statement will be guided. His description already differs from that
of some of his fellow-witnesses, as will be expressly considered
below; but he confesses that while, in point of persuasion, he much
inclines to the idea, that all the light displayed by the Aurora is
in itself white, and only tinctured to the eye of the spectator by
the atmospherical medium through which it is seen; and while, with
respect to all those deeper colours, whether crimson or purple, or
blood-colour, which appal the superstitious, and are described by the
picturesque narrator as exhibiting the terrible in matters of vision,
he judges it supposable that the whole machinery consists in the same
interposition of vapour, near the horizon, which so often gives to
the sun and moon themselves the appearance of being coloured like
blood: while, therefore, he still adheres to his opinion, that the
colours ascribed to the Aurora are wholly extrinsic; and, to borrow
the words of a scientific writer, “dependent upon the medium through
which they are seen;” he is obliged to acknowledge, that it did
appear to him, that the several columns, in truth, were yet variously
coloured, of pale, but bright and pleasing colours, from a pale
yellow to a pale pink and a pale violet, and this in the direction
of their height or length,—a phenomenon which wholly excludes, as
to those columns and their colours, the influence of an interposing
medium, the effect of which would be perceived horizontally, and
across the whole range of columns, or part of the range, and not
[p390] vertically nor obliquely, according to the direction of each
column, and within the limits of its sides. He confesses, also, that
he did take notice of the pale, but bright violet-coloured column,
distinguished also by its breadth and height, and situated to the
west of north; but which column, he is surely right in adding,
ultimately moved, with those next to it, toward the north. He
distinctly and pointedly observed, at the same time, that the columns
which stood due north were always white, and that the colours of
the other columns appeared to strengthen in proportion as they were
distant from the due north, either west or east; and he came to a
fixed conclusion, while the phenomenon was under his eye, that, to
his judgment at least, the strength of the fire, so to say, was in
that point of the horizon which lay due north; and that there was a
diminished brightness, with a proportionable increase of colour, to
the right and left.
3. As to the separate movements of the columns, these, in the first
place, were quick, and forced upon the eye, while the movement which
gradually deployed or advanced the right wing of the celestial
arm, and gradually contracted or withdrew the left, was slow, and
perceived only by its results; and, in the second place, while these
latter were parallel to the horizon, the former were either vertical,
or in the oblique or curved direction of the bodies of the columns.
But this motion consisted either in vibration, or in irregular but
alternate projections and contractions; and the motion of each
column, as has been said, was independent on that of others. Rarely,
two adjoining columns were in motion at the same time. Almost always
the moving column or columns were seen to start from the midst of
others, which, for the time, were quiescent, but which had had their
turn before, and would presently have it again. What eminently struck
the writer, however, was the internal motion of that to which he
cannot allow himself to give another name than that of the apparent
luminous material of the columns. It seemed to him as if the volume
of each column or coruscation was itself composed of parallel lines
of luminous matter, arranged in the direction of the column, and
every one of which was separately the subject of movements similar
to those of the entire [p391] column, or entire bundle of lines; or
as if the whole column were like the stalk of a plant, and filled
with upright and luminous fibres, or like a skein of thread, drawn
vertically or obliquely, and of which each particular thread should
have particular motion in the direction of the whole; or (what he
thought the comparison which proclaimed the very nature of the
material of the columns) like fountains, or jets of water in the sun,
in which every particular particle should be moving in the general
direction of the jet, and yet each moving and shining for itself.
4. And this apparent nature of the substance of the columns or
coruscations allies itself to what finally regards them; namely,
their form. In this description, they have hitherto been spoken of by
the name of columns or pillars; and the similitude, which that name
suggests, is justified by the general figure of all the lower parts
of their bodies, which, unlike the figure of rays of light on the one
hand, and unlike that of flames of fire on the other, is a tall or
lengthened object, of small comparative diameter or breadth, and of
which the sides consist in right and nearly parallel lines. But, by
the English, these columns, pillars, or coruscations, were anciently
called so many _burning spears_; and they have also received the
names of _streamers_ and _pencills_[121], which two latter, in the
history of appurtenants of war, signify long and narrow, and pointed
banners or flags. Their similitude to flags is excusably fancied from
their quick, capricious, and irregular motions, but their likening to
“spears,” is that which may claim to be thought the most felicitous,
as to the true conception of their form, as it is also that, the idea
of which contributes to render the phenomenon the most fearful in the
[p392] survey of ignorance and superstition. But the SPEAR-SHAPE
is descriptive, because the coruscations, unlike rays of light, and
unlike flames of fire, have neither the obtuse figure of a pyramid,
nor the acute one of an obelisk, upright or reversed; but, after
rising, through almost their whole height or length, of an equal or
nearly equal diameter, terminate in a point which is formed, not of
right lines, like the point of a dagger, but of curved lines, so as
to form the rounded point of a spear, or that figure which is so
familiar to botanists, as spoken of “spear-shaped” leaves. A ray of
light, in whatever direction it is thrown, broadens, with right-lined
sides, from the first point of its departure, to the furthest stretch
of its projection; a flame of fire points uniformly upward, with the
same regularity of form, excepting only as it is liable to undulation
from the motion of the atmosphere; but, the columns, spears,
streamers, or coruscations of the Aurora Borealis, have no form but
that under review.
5. About half-past eleven o’clock, or nearer to twelve, several
powerful columns shot toward the zenith; while, to the east of north,
others were at once curved in their form, and projected in an angle
of about thirty degrees with the horizon. But while, upon the west
of north, the sky, above the ridge of clouds, was entirely clear, so
that, there, the columns played upon a ground which formed a slight
contrast with themselves, here, the clouds were still heavy, and
the columns behind them appeared, in consequence, of a fiery red,
deepening as they approached the outer edge of the whole display, at
which was the sharpest outline, contrasted in the distinctest manner
with the dark sky. The light upon that side called to the mind of
the writer the “dunnest smoke of hell,” of Macbeth; while, as to its
outer line, as seen from the east end of Pall-mall, the sides of the
stone spire of St. Martin’s church, which rose to the eastward of
it in the sky, were not more sharply defined; the dark intervening
sky affording relief to both, though not equally so, upon account of
the superior brightness of even the obscured columns. But, in taking
leave of this columnar, or spear-like, and main part of the Aurora,
it may be permitted to add, that, in those tapering forms, together
with their motions, (though the comparison [p393] may still be
sufficiently remote and fanciful,) it was easy to discern the origin
of their having been resembled to weapons of war; that is, to the
spears of an army, raised, lowered, laid at angles, and gleaming,
glittering, crossing, and clashing in battle. And equally, too,
from their quick, varied, and separate, and, as it were, whimsical
motions, might they reasonably receive, in their milder displays,
and in moments of more peaceful and cheerful association, the very
different name of _merry dancers_!
* * * * *
III. Though, as will presently be found, it is the ruling idea of
the present writer, that the Aurora Borealis is a single object,
its appearance, when unmodified by the accompaniments of clouds or
fogs, being merely that of its own coruscations, playing in the
free expanse, yet for the purposes of analytical description and
contemplation, it is here thought convenient to divide it into
the three parts in which, through the temporary and accidental
intervention of the coloured arch before-mentioned, it appeared in
the night now in recollection. These three supposititious parts,
then, may be understood as follows: first, the arch, belt, or band
which was temporarily thrown across the heavens; second, the main
body of the coruscations below the arch; and third, the coruscations
above it, and in or near the zenith. It is of these only that it
remains to speak.
It was not till about midnight that the zenith itself (which,
however, formed the southern boundary to this part of the display)
became the scene of a class of appearances, differing, indeed,
essentially, in their forms, from those in the horizon, but closely
connected, as it may be believed, with all the materials, and all the
movements, of these latter. The zenith, at that hour, was cloudless,
and resplendent with stars, and the air was freshened by a gentle
breeze from the south. Between the earth and the stars above, there
was no apparent intervening vapour, and nothing, therefore, save
that atmospherical fluid which eludes the sight. But, through that
medium, if such only it was, coruscations were now continually
shooting, of which the appearance was, that it overspread this
portion of the vault of heaven with an ever-shaken [p394] sheet
of thin, gauzy, white, or yellowish-white, and nebulous, or cloudy
matter. To the writer, this superior portion of the Aurora, though
not the most lustrous, and, therefore, not the most striking of the
whole, was yet by no means the least interesting and inviting to
attention; for, here, as its appeared to him, the _material_ and the
manner of operation of the meteor were brought nearer to the eye,
and exhibited with such a back-ground (the starry heavens) as gave a
transparent view of the same matter as that, which, (as he thought,)
seen vertically, and in the horizon, appeared comparatively, at
least, opaque. The transparent medium, however, above, through which,
even when shook or vibrating, and even when whitened with light,
the stars were always seen in more or less brightness, was now in
continual motion; or, meteoric light or matter was continually,
though irregularly, and as it were, playfully shot through it. The
illuminated substance (whether the atmospherical fluid, reflecting
the light of the meteor, or the luminous body of the meteor itself,
but probably the latter) was incessantly discovering itself in
different places; now here, now there, now bright, now dim; but far
less in a manner, or with an appearance, such to be compared with
lightning, than with such as resembled the changes of ripple upon the
bosom of a wide-spread water, when a variable breeze blows over it;
first in one part, and then in another; and now in one direction,
and the next moment in a second. Or, the canopy of heaven, at this
time, might be said to be composed of a lace or gauze bearing a
figured pattern, of which the fluttering motion continually changed
the places, or hid or re-displayed the figures represented; or the
picture, perhaps, will be more easily imagined, if conveyed in the
very appropriate language of an older hand, which, referring to
the appearances displayed in the zenith, remarks, “They break out
in places where none were seen before, skimming briskly along the
heavens; are suddenly extinguished, and leave behind a uniform dusky
track. This, again, is brilliantly illuminated in the same manner,
and as suddenly left a dull blank.” It should be understood, however,
that, at least as seen by the present writer, in this mixture of
white and blue, the blue was always the preponderating colour; or,
in other words, [p395] that, the field of the unoccupied zenith
always bore a large proportion to the space or spaces covered,
however momentarily, with light, or with the luminous substance.
For the rest, the particular mentioned in the passage which has now
been quoted, namely, that of the residue of a dusky track, after
the departure of the white light, did not, if it was there, attract
the attention of the present writer, upon the late occasion; but he
certainly, in many instances, remarked the return of the light to
the places in which it had been visible before; and this feature,
either with or without that of the continuance of a dusky track,
is possibly capable of adding some support to the general opinion
which he conceived at the moment, which all subsequent information
has still allowed him to retain, and of which he proposes to make
further use; namely, that the appearances in the zenith are only
extended exhibitions of the luminous phenomena in the horizon, or
their southern extremities, or the tops of columns projected from the
northward. He thought that, in the zenith, he saw the same material,
parcelled out, attenuated or diluted, spread thin, and, as it were,
shown with greater transparency, with that which, in thicker volume,
with more accumulated strength, intenser light, with more solid body,
and withal behind a denser mass of atmospherical vapour, arose, and
glowed, and sometimes gloomed, in the horizon. But, be this as it
may, it is, perhaps, this upper part of the exhibition, in which the
lights or streamers seem to interweave, or cross and recross each
other, to dance in and out of the area, and to indulge in motions
still more capricious or anomalous than is probably the real fact; it
is, perhaps, this upper part which has alternated, as before recalled
to view, the names and similitudes of spears, gleaming, glittering,
interposing and clashing as in battle, and of _merry dancers_, the
latter the gayer comparison of the dancing north.
* * * * *
IV. The Aurora continued to fix the attention of the writer till
between twelve and one o’clock of the morning of the 26th; and he
presumes that it continued visible till the superior light of the
rising day eclipsed its glory. The 26th was warm, but oppressed with
fog, through which the sun broke [p396] only at intervals; and,
between four and five o’clock in the evening, a small but steady
rain commenced, and continued, or rather increased in heaviness,
till after midnight. Between eleven and twelve, while it still
rained, the writer, on looking at the sky, which was covered with a
uniform mass of clouds, the writer observed, from point to point,
over the northern and southern hemispheres, a glow of ruddy light,
which he suspected, and still suspects, to have been produced by the
light of the continued Aurora, reflected by the vapour. He took the
opinion of a fellow-traveller, which coincided with his own; but it
has not come to his knowledge that any individual, himself and his
companion excepted, has formed a similar conjecture—nor, indeed,
is it impossible that it was no more than the light of the hidden
moon. The night of the 27th was star-light, though with fog near the
surface; and there was then no appearance of an Aurora. The night
of the 28th was remarkably clear, and there was still no return of
the Aurora. The morning of the 29th was warm, with continued and
heavy rain; but, after this, there succeeded a week or more of clear
and dry weather; and these united particulars close the history of
the phenomenon, as far as belong to the personal observation of the
writer. The direction of the winds, and the state of the barometer
and thermometer, were of the same general description, during many
days subsequent to the appearance of the Aurora on the 25th, as
that which had belonged to them from the 20th, and almost for many
days before, and of which the particulars have been stated above;
and these remarks may merit record, as connected with the question
of the ordinary duration of the Aurora, and of the weather by which
it may be thought produced, or which it may be thought to bring. In
many instances, it has been observed, even in its splendour, and
even in southern latitudes, for several nights in succession; and
an influence upon the weather has likewise been expected from its
appearance. Upon this occasion, there was no remarkable change in
the latter till the night of the fourteenth day after the Aurora
(October 10th), when there occurred a violent gale of wind from
the south-west, accompanied with loud thunder, and the most vivid
lightning; subsequently to which, as usual, [p397] the air, for a
few days, was felt to be cooler than before. It has been said, that a
gale of wind, from the south-west, is always to be looked for within
twenty-four hours after the Aurora.
* * * * *
V. The astronomical writer, already more than once mentioned,
speaking of the Aurora of the 25th of September, describes it as
“that mysterious phenomenon;” and Mr. Adams, the meteorological
correspondent of the publication referred to, records it as,
“perhaps, as conspicuous as any that has ever been seen in
England[122];” so that, assuming these impressions in both instances
to be well founded, neither the present state of science upon the one
hand, nor the specimen of the phenomenon upon the other, are such
as to discourage either of the objects of the remainder of these
pages; namely, the one to contribute, as fully as possible, to the
completion of a faithful account of the Aurora, as seen in London
upon the late occasion, by uniting, and by analysing the descriptions
that have caught already the eye of the writer; and the other, to
correct, and to enlarge if it should be practicable, the natural
history of this description of meteor, by the comparison of what has
hitherto been usually written upon the subject, either descriptively
or philosophically, as well with the results of the late actual
observations, as with the several facts or opinions more anciently
registered. According to some, the interval which had elapsed, since
an equal or a superior display of this phenomenon was witnessed in
London, is twenty-four years, and, according to others, thirty-six;
nor is the scanty list of examples scientifically recorded, at all
inconsistent, from the wide separation, as well as irregularity
of its dates, with such a view of the infrequency and uncertainty
of any considerable appearance in other southern latitudes. The
opportunity, therefore, now offered, ought not, perhaps, to be
neglected; and the writer is not wholly without the prospect, that,
upon a re-examination, both of opinions and facts, some safe and
inevitable conclusions may be elicited, both as to the history
and the theory of the meteor, hitherto, the one hastily received,
[p398] and the other negligently overlooked, or unwarrantably
contradicted. The paragraphs, then, which immediately follow, will
connect and review the accounts of the writer’s fellow-observer of
the 25th of September; while those which succeed will be devoted to
a brief enumeration of statements already recorded in books; though,
to a certain extent, both these paths will involve us in mixed
investigations, historical and theoretical.
1. “It first appeared,” says Mr. Adams, who dates from Edmonton, in
Middlesex, “about eight o’clock in the evening, as a strong white
light, much resembling the approach of sunrise; and so continued till
a short time after eleven, when a considerable number of dark clouds
collected toward the north and north-west, and several streaks of a
pale white light were seen proceeding from the clouds, and reaching
nearly to the zenith. But the most remarkable part of the phenomenon
was exhibited in a N.N.E. direction, where, at about 30° above the
horizon, was a small dense cloud, above which was a broad streak
curved, and about 10° in length, varying in colour from a deep copper
hue to a red.” “From this,” continues Mr. Adams, “the coruscations
were incessant, and remarkably bright, darting frequently to the
zenith, where they were frequently crossed by others equally bright
and numerous, proceeding from the west toward the east.”
2. The astronomical writer, who dates from Deptford, describes
the phenomenon as commencing at a quarter past eight o’clock, and
travelling, from west and north-west, to north-east; and the streaks,
or streamers, or, as he denominates them, the flashes, “converging
to the zenith,” and “coruscating with great velocity.” He also
particularises the peculiar appearance of “a streak or column of a
phosphorescent violet tinge;” and adds, “The _two_ red beams of
light, seen in the _easterly_ and _westerly_ direction [directions],
were diametrically opposite to each other, and ninety degrees distant
from the violet light (by far the most luminous, though comparatively
quiescent) which was to the west of north, _and therefore could not
be far from the magnetic meridian_, which would be crossed at right
angles by a line joining the places of the red beams. The southern
edges of these were accurately defined, not blending with the
adjacent azure, but most distinct from it, and [p399] perpendicular
to the horizon.” Finally, this gentleman speaks of the general
luminous aspect, as “much resembling the tail of a comet,” and says,
that Ursa Major, and other stars, were visible through its medium;
that three meteoric stars also appeared, during the phenomenon, in
the east and north-east; and that the entire horizon was obscured by
dark, heavy clouds, from three to five degrees in height[123].
3. Besides these observers, two or three others, if not many more,
less scientific, perhaps, but yet entitled to attention, have
communicated to different newspapers their accounts of the same
phenomena. “The metropolis,” says one of these, “was surprised on
Tuesday night by a brilliant display of Northern Lights, which but
very seldom stray so far south. The last which we beheld in London
were in the autumn of 1804, about the end of September, or beginning
of October; and the fancied prodigy filled all the superstitious
heads, at the time, with fearful prognostics, and loosened the
tongues of a hundred prophets. The spectacle, then, was truly
magnificent. On Tuesday night (the 25th) the northern parts of the
heavens displayed, about eleven o’clock, so ruddy a blaze, as to
appear like the reflection of a mighty conflagration. An hour later,
the red hue was gone; but the whole horizon, from the north to the
east, was lined with _a thin cloud_, from which the rays of light
rolled, or sudden rays flashed up, and as suddenly vanished, to
appear in a different part.” “At about half past eleven o’clock,”
says a second, “my attention was attracted to a singular appearance
of light and streakiness in the sky. I observed it for nearly two
hours. The sky, to the north, was obscured, for about fifteen degrees
above the horizon, by a _dense_ stratum of black clouds; from the
upper edge of this, the light became first apparent, extending from
nearly north-east to north-west, exceeding considerably in power
that arising from the moon just previous to its rising. From this
broad stratum of pale yellowish light shot beautiful _pencils_,
of a luminous, hazy appearance, up to the very zenith, changing
momentarily in length and intensity. During this period, the wind
blew gently from the south; and I frequently observed, that when it
freshened [p400] a little, the Aurora Borealis became more brilliant
in its appearance, sending beautiful coruscations of light, in rapid
succession, towards the zenith, and frequently passing that point ten
or fifteen degrees to the southward. I have been assured, by those
who are well acquainted with this beautiful phenomenon, that they
have not seen any appearance of it equal in brilliancy and beauty
to this, for upwards of six and thirty years.” “Last night,” says a
third, “we were favoured with that interesting phenomenon, the Aurora
Borealis, or Northern Twilight, which so often amuses and cheers
our neighbours in the north, but seldom, I believe, is seen in our
latitude. It was without those varied colours,” adds this writer,
“which cause it to be a grand spectacle in those regions.” “Not
far from the horizon,” he adds, “in the northern hemisphere, were
transparent bodies of light, _eclipsing_ the brightness of the stars,
which, however, were perceptible through it. From hence, beams of
light, varying in degrees of brightness and breadth, shot up towards
the zenith; here streamers of light flew from the east to the west,
and from west to east. The southern hemisphere was cloudless, the
stars shining with brilliancy. By the light of this phenomenon, I
could discern the time of night, which was between eleven and twelve,
as well as other objects, as they appear on a moon-light night,
when the moon is obscured by clouds.” “The sky in the north,” we
are told by the fourth, “appeared as if a light shone from behind
some dark masses of clouds. As I approached Hampstead, the silvery
light was gradually tinged with rosy spiral streams, like those
which sometimes precede the rising and follow the setting sun. These
spiral red streaks did not appear to move quickly; but they were
subsequently followed by the _merry dancers_, which fully maintained
the character bestowed upon them by our northern neighbours. After
passing through Hampstead, I crossed the heath, and came down what
is called North-end Hill, to Golder’s Green, Hendon. When you arrive
at the foot of the hill, you enter upon the open part of Golder’s
Green, where you have a clear and unobstructed view of the sky from
west to north. I never shall forget the grandeur of the scene which
awaited me there. A continuous border of dark cloud skirted the
horizon completely from west to north, whilst [p401] from behind it,
incessantly and rapidly shot up the most beautiful coruscations of
white light, which, being relieved by the dark border, added double
brilliancy to the ever-shifting scene.”
* * * * *
VI. But, after transcribing these respective accounts, it may be
permitted, for the purpose of uniting them with that submitted in the
preceding pages, to remark,
1. That the account by Mr, Adams, of the appearance worn by the
Aurora at an early hour in the evening, is, no doubt, entirely
correct; and that it is easy to understand, from this description of
that early appearance, why little observation was attracted to the
phenomenon till about eleven o’clock at night, the time assigned, as
well in this, as in all the other accounts, for the commencement of
the phenomenon.
2. That the “streaks of a pale white light,” which Mr. Adams
describes as proceeding, a short time after eleven, “_from_ the
clouds,” must be understood, as stated by the writer last quoted, as
proceeding “_from behind_ the clouds;” that, when the astronomical
writer at Deptford speaks of Ursa Major and other stars being seen
through the Aurora, it must be recollected, that, perhaps, this
remark should apply to the medium of the thin and shifting lights in
or near the zenith; and,
3. That it is with respect to the “broad streak, curved,” of Mr.
Adams; the “_two_ red beams of light,” of the astronomical observer
at Deptford; and the “arch” of the present description, that the
principal, if not only discordance obtains. Neither of the other
three writers appears to have seen any thing, whether of one “broad
streak, curved,” and “varying in colour from a deep copper hue to a
red,” or of “_two_ red beams,” as spoken by the writer at Deptford;
while, in each of the three accounts in which that part of the
phenomenon is actually referred to, the descriptions are materially
dissimilar:—
1. The writer at Edmonton mentions only a single streak, while the
writer at Deptford speaks of _two_.
2. The writer at Edmonton describes his single streak as curved,
while the writer at Deptford says nothing of curvature; and, in
describing the position of the beams as “perpendicular to the
horizon,” may seem to leave no curvature to be understood. [p402]
3. The writer at Edmonton seems to lift his “broad curved streak”
much above the horizon; for he first places a small dense cloud 30°
above the horizon, and, then, his broad streak above the cloud;
thus describing a curve of which the situation was near the zenith,
while the writer at Deptford is describing “two red beams,” standing
perpendicularly to the horizon.
4. The writer at Edmonton places his “broad streak, curved,” “in a
N.N.E. direction;” while the writer at Deptford records “two red
beams of light, seen in the easterly and westerly direction.” Lastly,
5. The writer at Edmonton seems to make coruscations, “incessant and
remarkably bright,” dart from his “broad streak, curved;” while the
writer at Deptford seems only anxious to place his “two red beams,”
as perpendicular pillars, standing on either side of the _magnetic
meridian_.
* * * * *
VII. And, from the whole of this, from the total silence of four
accounts, and from the extreme discordance of the other three, the
present writer presumes to draw the following inferences, including
that of the accuracy of his own original statement:
1. That the two perpendicular red beams of light, of the writer
at Deptford, should be joined with broad curved streaks of a deep
copper, or red hue, of the writer at Edmonton, to complete the _arch_
which has been spoken of in the foregoing pages.
2. That this _arch_, or curved streak, with its feet east and west,
sent forth no coruscations itself; but that the coruscations rose
beneath it, and passed above it.
3. That it was described upon the clouds only; was no part of
the Aurora; and, from its connexion with the clouds only, had
an evanescence which, on the one hand, was the cause of the
various descriptions, and, on the other, of no descriptions at
all. The present writer observed this part of the phenomenon from
its beginning to its ending. He saw it rise in the west, extend
itself from the north, and descend in the east; and he thinks it
reasonable to ascribe the variations concerning it, in the coincident
narratives, to the different points of time to which alone they
really refer. The writers at Edmonton [p403] and Deptford seem to
have had their attention fixed upon it at different epochs of its
progress; and all the four other writers, who have been cited, seem
to speak of a time subsequent to its disappearance. The present
writer does not recollect the small cloud below it, spoken of by
Mr. Adams; but he well remembers the clouds above it, and along and
near the northern edge of which it seems to be formed. He does not
recollect seeing its definite _southern_ outline contrasted with the
azure sky; but he well remembers seeing that outline contrasted with
the dark clouds above it, or to its southward; and also the contrast
of its definite, _northern_ outline, as contrasted with the azure sky
beneath.
* * * * *
VIII. It is necessary to take notice, also, of what is said above,
by the astronomical observer at Deptford, as to the “flashes
converging to the zenith,” and, further, of the omission, both by
this writer and by Mr. Adams, to speak of the curved beam, streamer,
or coruscation, to the east of north, as described above. The whole
veracity of the foregoing description depends upon the denial
of a uniform convergence of the streamers, pillars, columns, or
coruscations toward the zenith; nor was it, in all probability, the
intention of the writer at Deptford, to assert any such convergence,
but only to speak of those coruscations, or shifting lights, in the
zenith, which are described by Mr. Adams as crossing each other from
east to west. It is remarkable, at the same time, that neither the
one nor the other of these writers have mentioned that direct reverse
of convergence which marked the general figure and arrangement of
the streamers or columns of the Aurora, and which was so opposite to
what would have been given to it by the phenomenon of convergence.
Indeed, the violent curve of the extreme column to the N. E. or N.
N. E., shrouded, too, as that column was with a body of dense vapour
through which its light appeared of a deep and dull red colour, might
make the description of this itself answer to the “broad streak,
curved,” of Mr. Adams, if we were not certain, from other particulars
mentioned, that Mr. Adams really refers to the curve which formed
part of the _arch_. For the rest, no mention of the real directions
of the several columns having been made by any observer of the Aurora
of the 25th [p404] of September but himself, and especially none of
the outward curve of the easternmost column, it is satisfactory to
the writer to have found an account of an appearance similar to this
last, in an Aurora of which he will presently have occasion to speak.
* * * * *
IX. Finally, there is an observation to be made upon that part of
the description, by the second correspondent of the newspapers,
where it is said, that during the appearance of the coruscations
in the zenith, “the wind blew gently from the south,” and the
spectator “frequently observed, that when it freshened a little,
the Aurora Borealis became more brilliant in its appearance;” to
which it may also seem the writer’s intention to add,—“sending
beautiful coruscations of light, in rapid succession toward the
zenith, and frequently passing that point, ten or fifteen degrees to
the southward.” Now the reality of any dependence of the light and
motion of the Aurora upon the freshening of the breeze, would seem
too strongly to affect the question of the nature and action of the
_auroral matter_, to be admitted without cautious examination. In
truth, what was it that constituted the luminous matter which we saw
in the zenith? The stars were visible through it. But for luminous
appearances that flew or skimmed along the heavens, we should have
said, that the latter were clear, and that there was nothing but the
purest atmosphere between the earth and the heavens. Was it, then,
the atmospherical matter which was thus illuminated, and which, being
ruffled by the breeze, can be supposed to have really exhibited
the appearances described by this writer, or, was it not, rather,
illuminated _auroral matter_, which was shot through the atmosphere;
and, if this last, how are we to understand that its brilliance, and
still less the frequency and vigour of its coruscations, could have
been affected by the freshening of the breeze?
* * * * *
X. But, taking, now, a final leave of the description of the Aurora
of the 25th of September, and of the observations specially suggested
by it, let us here examine the several particulars which are commonly
offered as part, at least, of its true history; an undertaking,
for the greater convenience of which the account given in a modern
work of much and [p405] deserved reputation, shall be quoted and
considered sentence by sentence, as follows:
1. “AURORA BOREALIS, _Northern Light_, or _Streamers_; a kind of
meteor, appearing in the Northern part of the heavens, mostly in the
winter time, and in frosty weather.
2. “It is in the Arctic regions that it appears in perfection,
particularly during the solstice.
3. “In the Shetland Islands, the Merry Dancers, as they are called,
are the constant attendants of clear evenings, and prove great
reliefs amidst the gloom of the long winter nights.
4. “They commonly appear at twilight, near the horizon, of a dun
colour, approaching to yellow; sometimes continuing in that state,
for several hours, without any sensible motion, after which they
break out into streams of stronger light, spreading into columns, and
altering slowly into ten thousand different shapes, varying their
colours from all the tints of yellow to the obscurest russet.
5. “They often cover the whole hemisphere, and then make the most
brilliant appearance.
6. “Their motions, at these times, are most amazingly quick, and they
astonish the spectators with the rapid change of their form.
7. “They break out in places where none were seen before, skimming
briskly along the heavens; are suddenly extinguished, and leave
behind a uniform dusky track.
8. “This again is brilliantly illuminated in the same manner, and as
suddenly left a dull blank.
9. “In certain nights, they assume the appearance of vast columns; on
one side of the deepest yellow, on the other, declining away till it
becomes undistinguished from the sky.
10. “They have generally a tremulous motion from end to end, which
continues till the whole vanishes.
11. “In a word, we, who only see the extremities of these northern
phenomena, have but a faint idea of their splendour and their motions.
12. “According to the state of the atmosphere, they differ in colour.
13. “They often put on the colour of blood, and then make a most
dreadful appearance[124].” [p406]
1. Now, with respect to the first and second of the sentences here
transcribed, there seems reason to doubt the accuracy of the account
which almost limits the appearances of the Aurora to the “winter
time,” to “frosty weather,” and especially to the winter “solstice.”
The frequency with which the season approaching to Christmas, or that
of the winter solstice, is distinguished by the occurrence of weather
peculiarly mild, insomuch that, almost every year, the period is
marked by observations upon what is annually called the extraordinary
and unseasonable genialness of the weather, cowslips blooming, leaves
budding, and birds building their nests; this frequency of a mild
temperature of the air about the period of the winter solstice, may
justify, even under a general view, a doubt of the accuracy with
which, as things of course, the winter solstice, and frosty weather,
are spoken of as arriving in conjunction. But, that the appearance
of the Aurora Borealis is not peculiar, either to the occurrence of
frosty weather, or to the period of the winter solstice, whether
the two latter phenomena are related or otherwise, seems probable,
as well from the mildness of the weather at the late appearance,
as from the various seasons of the year in which the few others
described in our books are recorded to have presented themselves.
The earliest mentioned was seen in London in the year 1560, on the
30th day of January. The next was in 1564, on the 7th of October.
The next, in 1574, on the 14th and 15th of November. The two next,
observed in Brabant, in 1575, on the 25th of February, and 28th of
September. The next, at Wurtemburg, as we are assured by Meestlin,
seven times, in the year 1580. The next, in an extraordinary manner,
in the months of April and September, 1581; and in a less degree,
at some other places, in the same year. The next, observed all over
France, in 1621, on the 2nd of September. The next in 1707,and 1708,
during which two years the Aurora was witnessed five times. The
next, in the month of March, in 1715–16. The next, in 1737, on the
16th of December; that seen in London in 1791, of the month of which
the writer is uninformed; another in 1803, or 1804, at the latter
of September, or the beginning of October; and this, of 1827, on
the 25th of September. But, from these statements, it is now seen,
that, [p407] exclusive of appearances of the Aurora in respect of
which the month is not particularised, eight of the different months
of the year occur by name; that is to say, the months of September,
October, November, and December, January, February, March, and
April; leaving only four months (May, June, July, and August, the
identical summer-months of the Polar regions, or months during which
the sun visits the Polar horizon!) hitherto undistinguished by the
phenomenon of the Aurora, and almost establishing, as the season of
its occurrence, not the middle point of the winter solstice, but the
whole period extending, in general terms, from the autumnal equinox
to the vernal, beginning at or before the first, and ending at or
after the last; or, what may be called the entire winter of the
northern hemisphere, or the period during which the sun’s course is
to the southward of the tropic of Cancer; a deduction from the scanty
data offered by such archives of the phenomenon as we possess, not,
perhaps, of trifling importance toward the establishment of the true
theory of the cause, as well as of the purpose of its being.
2. The third sentence, where it describes the Aurora Borealis as the
_constant_ attendant of clear evenings in the Shetland Islands, and
thereby a great relief to the gloom of the long winter-nights, is
probably tainted with errors in regard to the phenomenon, such as
affect its whole history and philosophy. The suggestion has just been
hazarded above, that at least considerable displays of the Aurora are
probably almost as rare, even in the Arctic regions, as in climates
further south; and the truth of this persuasion, as the writer
anticipates, will fully appear below. In the sentence now referred
to, the word “constant” should, at least, give way to “frequent,”
if not to “often;” and a distinction should be allowed for, between
those feeble appearances which alone, it may be suspected, are even
_often_ beheld in the Shetland Islands, and those extraordinary
displays which make themselves visible to their southward.
3. The fourth of the above sentences, in which the Aurora is said
to appear commonly at twilight, will have been seen to agree with
the time assigned for the commencement of the Aurora in the late
example; and this, when coupled with the [p408] observation in the
third, that, in the Shetland Islands, it is the constant attendant of
_clear_ evenings, will seem to suggest, what, indeed, will probably
be easily agreed to, that the Aurora, in itself, is peculiar neither
to clear evenings nor to evenings at all; but is in activity during
the twenty-four hours, or without intermission; though, to be visible
to human eyes, first, the atmosphere must be dark, and, secondly, it
must be more or less clear. It may also be thought apparent, from
the terms of the twelfth and thirteenth sentences, that too much
has not been said by the present writer, of the degree in which the
peculiar spectacle, upon each separate occasion, depends, not alone
of the proper and really uniform features of the Aurora itself, but
also of the atmosphere through which it is seen, with the appearance
of which its own appearance is combined; and of the consequent
value of a careful separation of the real phenomena of the Aurora,
from the adventitious phenomena of the intervening and surrounding
atmosphere. That the colours which, whether visibly connected with
the atmosphere or otherwise, are displayed during the appearance of
the Aurora Borealis, are wholly derived from the atmospherical medium
through which we behold it, and that the Aurora itself exhibits
only a pure white light, is what the writer greatly inclines to
suspect, and what may seem to be rendered still more credible by
that which is reported by those who have obtained a partial glimpse
of the Aurora _Australis_, or corresponding phenomenon of the south.
This is described, by Mr. Forster, who sailed round the world with
Captain Cook, as consisting in “long columns of clear white light;”
but the whiteness, in the eyes of the narrator, seemed to establish
a difference, instead of a similitude, between the Auroræ Australis
and Borealis, Mr. F. wholly overlooking the explanation which his own
account supplies! “These columns,” says he, “though in most respects
similar to the Northern Lights (Aurora Borealis) of our hemisphere,
yet differed from them in being always of a whitish colour, whereas
ours assume various tints, especially those of a fiery or purple hue.
The sky was generally clear when they appeared, and the air sharp
and cold, the thermometer standing at the freezing point.” Now this
text is its own commentary. The [p409] Aurora could not have been
seen if the sky had not been more or less _clear_. But the sky was
_very clear_; and this because the weather was _severely frosty_.
The thermometer “was standing at the freezing point.” The weather
was settled frosty, and therefore settled clear; for the Aurora
appeared for “several following nights.” The atmosphere, therefore,
was clear; there was neither cloud nor fog, and thence the whiteness
of the Aurora. But these views of the Aurora _Australis_ were
partial occurrences, and were characterised, as we must conclude,
by the state of the atmosphere at a particular conjuncture, or at
a particular season of the year. In point of fact, the Aurora was
seen on the 16th of February, 1773, in latitude 58° S. This was the
beginning of the Australian winter, and it might be a very cold, and
therefore a very clear beginning. But the atmosphere of the southern
half of the globe is not always thus translucent; and when it is
otherwise, we may depend upon it that the columns of its Aurora
“assume various colours; especially those of a fiery and purple
hue,” more or less like our own. A friend of the present writer
was in the same latitude (58° 12′ S.) in the month of March, a few
years since; and, upon asking that gentleman whether he had ever
beheld an Aurora in the Southern Hemisphere, his answer was in the
negative. The season of his visit, however, was a month later in
the southern winter than the visit of Messrs. Cook and Forster; the
weather was thick and sleety; it was unfavourable to any view of an
Aurora at all; but, had the phenomenon happened to present itself,
its appearance, we may believe, would not have presented that of a
uniform, clear, white light.
4. In the fourth and sixth sentences, what is said of “change of
shape,” and “change of form,” is of a nature exceedingly to mislead
such as, never having themselves witnessed the phenomenon, may
desire either to figure it to their imagination, or to reason upon
its appearances. In reality, there is no such change of shape or
form as the words naturally suggest to our ideas; the forms, under
all changes, are still linear; and the actual changes, as to form,
are limited to such changes only as can be produced with the single
material of lines, lengthened, shortened, varied in their direction,
and now fixed, now shaken, now darting; and now joined in rapid and
intermingling motion. [p410] Add, that these lines are luminous,
and varied in colour from white to yellow, red, and crimson, and,
sometimes, perhaps, to purple and to violet; that they play, in the
lower heavens in a field of light, and in the upper over a sky of
blue; and the picture of the Aurora Borealis is well nigh complete.
The observation in the ninth sentence, that the vast columns, of
which, upon some occasions, the Aurora displays the forms, are of a
deep yellow upon one side, which, upon the other, fades gradually
into that of the sky, is to be understood, as expressing, that, as in
the late example, the outer edges of the columns, or those next the
dark or unillumined portion of the horizon, are sharp and strongly
defined; while the inner ones are less distinguished from the general
field of light in which they stand; and which distinction, after
all, is but a delusion of the eye, which more readily distinguishes
the variation of colour in the outer edge, which is so strongly
relieved by the dark and colder-coloured part of the sky, than the
colour of the inner part and edge of the column, which, more or less,
approaches that of the ground behind it.
5. Sentences seven and eight appear to the present writer to convey
the most accurate description possible, of the appearance of the
Aurora in the _zenith_. The “dusky track,” which remains after
the lights which have enlivened it are extinguished, and in which
they are so often seen again, may seem to attest the justice of
his opinion, that these appearances in the zenith are no other
than the far-projected tops of the columns which have their bases
in, or rather below, the horizon; tops which, while they fill the
southern half of the zenith, to the view of spectators under our
parallel, must gradually descend toward the horizon, in the eyes of
such as behold them further and still further to the south; till,
like the topmast of a receding ship, they first scarcely remain
discoverable above the convexity of the surface intervening, and
finally dip and sink beneath it. But, upon this assumption, the
appearance, and therefore office, of the Aurora Borealis, must
be conceived as extending far to the southward of even our own
island; and the statement, as in the eleventh sentence, becomes
more or less inaccurate, that “only the extremities of these
northern phenomena” are witnessed by ourselves. In reality we are
[p411] ourselves inhabitants of the Northern hemisphere; and the
relationship of the Aurora to the wants of the whole hemisphere is
more extended, perhaps, than we have commonly imagined. It is even
a contradiction to say, as in the eleventh sentence, that we see
only the extremities, that is, the Southern extremities of these
Northern phenomena, after having said, in the fifth sentence, that
“they often cover the whole heavens, and then make the most brilliant
appearance;” unless, indeed, in both of these remarks reference
is made to the spectacle beheld under more Northerly parallels, a
reference which is further suggested, together with their apparent
origin, in the terms of a description by Gmelin, to be cited below,
of the Aurora as beheld upon the coasts of the Icy Sea; If the
Aurora, there, or upon the banks of the Lena or Yenesei, is seen
to rise in the north, but yet to stretch itself over the whole
hemisphere, it must follow, that its “extremities,” that is, its
southern extremities, so far from being all that is seen in these
situations, are really projected, on those occasions, so far to the
southward, as to escape the ken of our northern optics; a fact of
which the explanation must be familiar, inasmuch as, owing to the
convexity of the surface of the globe, the horizon of every part is
narrowly bounded, whether upon the South or upon the North; whence
it results, that any celestial, or even atmospherical appearance,
stretching only a little way beyond us to the Southward, or toward
the East, or toward the West, must soon reach the horizon upon
either of those sides, and thus cover all that, to the eye of any
individual, is visible of the “whole hemisphere.”
6. But the description, by Gmelin, of the Aurora, as seen upon the
shores of the Icy Sea, and more than all, the simplicity with which
the naturalist is disposed to fix its birth-place in that precise
interval of the earth’s surface which divides the mouth of the river
Yenesei from that of the river Lena, in the North-east of Asia, (a
spot so far to the _North-eastward_, too, of our own!) while it may
possibly explain the origin or bearing of remarks, that it “sometimes
covers the whole hemisphere, and then makes the most brilliant
appearance,” will also afford something of an answer to such as, with
the writer quoted above, seeking to connect the Aurora Borealis with
the [p412] Magnetic Pole, would discover its same birth-place, or
focus, in the _North-west_, or nearer to the North-west of America,
than to the North-east of Asia! It may furnish a reply, also, to
Gmelin himself, who, though he tells us that, even upon the banks of
the Lena and Yenesei, the Aurora is still seen to rise to the North
or North-east of those situations, yet imagines those very banks to
be its “real birth-place;” for is it not plain, in the meantime,
and this from the very statement of the author, that, travel as far
northward, or north-eastward, as we will, the birth-place of the
Aurora still retires from our feet; that, even upon the shores of the
Icy Sea, the joyous phantom is still to our Northward, or North-east,
and that we may reasonably conclude, that even a voyage upon that
sea would not carry us to the cradle in pursuit; that, in short, at
the North Pole, we should still behold it rise in the North, or the
North-east, or the North-west; that we might sail down the Western
Hemisphere, and yet only discover, that the Aurora was now in the
North behind our backs, as it had been before in the North before our
faces; and that, in short, so long as we do but admit its existence
in the North, the particular soil or sea is best described in the
most general terms:—
“In Nova Zembla, or the Lord knows where!”
The search, too, for the paternal hearth of the Aurora Borealis in
any particular division of the Northern Hemisphere, and especially
the attempt to find it at the Magnetic or Electric Pole, is, perhaps,
so much the more hopeless, after ascertaining, as above, that each
hemisphere has its Aurora; and after concluding, as we may have
been led to conclude with reason, that each Aurora, other things
equal, resembles the other! What is remarkable, also, is that, in
the Southern Hemisphere, as well as, according to Gmelin, in the
Northern, it is to the Eastward, or to the East of North, that the
Aurora has its apparent focus. “A beautiful phenomenon,” says Mr.
Forster, (Feb. 17, 1773, lat. 58° S.) “had been observed during the
preceding night, which appeared again this and several following
nights. It consisted of long columns of white light, shooting up from
the horizon to the eastward, almost to the zenith, and gradually
spreading over the whole southern part of the sky. These columns
are gradually bent sideways [p413] at their upper extremities; and,
though in most respects similar to the Northern Lights (Aurora
Borealis) of our hemisphere, yet differed from them in being always
of a whitish colour; whereas ours assume various colours, especially
these of a fiery or purple-hue. The sky was generally clear when they
appeared, and the air sharp and cold; the thermometer standing at the
freezing point.” This occasional bending of the columns, “sideways
at their upper extremities,” instead of uniform convergence toward
the zenith, observed by Mr. Forster in the Aurora of the South, is
plainly the same peculiarity which was recently witnessed in London,
in the Aurora of the North, and a circumstance which, in whatever
way explained, assists in the identification of the natures of the
two phenomena; and, if we are still to hesitate, upon account of the
whiter light of that of the South, let us believe that particular to
originate in some peculiar constitution of the Southern atmosphere,
from which, in one way or another, not here to be discussed, the
cause of the difference may offer itself. But Gmelin’s account of
the Aurora of the North, to which the attention of the reader has
already been called, is that which is here required to follow. It is
to serve to illustrate, as will be remembered, much of the foregoing:
“This Northern Light,” says that author, “begins with the rising of
single light pillars in the North, and almost at the same time in the
North-east, which, gradually increasing, fill a large space in the
heavens, rush about, from place to place, with incredible velocity,
and finally almost cover the whole sky, up to the zenith: the streams
are then seen meeting together in the zenith, where they produce an
appearance as if a vast tent was expanded in the heavens, glittering
with gold, rubies, and sapphires. A more beautiful spectacle cannot
be described; but whoever should witness such a Northern Light for
the first time, could not behold it without terror; for, however
beautiful the illumination may be, it is attended, as I have learned
from the relation of many persons, with a hissing, crackling, and
rushing noise, throughout the air, as if the largest fireworks were
playing off. To describe what they then hear, they make use of
the expression, ‘Spolochi chodjat;’ that is, ‘The furious army is
passing!’ The hunters, who, upon the confines of the [p414] Icy Sea,
follow the chase of the blue and white foxes, are often overtaken in
their excursions by the Northern Light; and, upon this occurrence,
their dogs are so much frightened, that they will not move, but cower
obstinately upon the ground till the noise is over. The weather,
after the appearance of the Northern Light, is usually clear and
calm. I have heard these accounts, not from one person only, but from
many of those who have spent several years in these very Northerly
regions, and inhabited different countries from the Yenesei to the
Lena, so that no doubt of its truth can remain; for here seems to be
the real birth-place of the Aurora Borealis.”
8. Upon this statement itself, it is only needful to remark, that the
rising of the pillars in the North-east, or to the East of North,
rather than to the North-west, or West of North, almost at the same
time with their first appearance in the North, is not, perhaps,
even as seen between the Lena and Yenesei, so uniformly the case as
M. Gmelin may have been led to believe; and that, at all events,
as above described, the progress of the late display, observed in
London, was, first from North to West, and afterward from West to
East; the North being always the centre, or always light, while the
West and East were changed. The covering of the whole sky, and the
splendour of the scene produced, have been the subject of previous
remark; and the observation, “that the streams (previously called
pillars) are then seen meeting together in the zenith,” entirely
corroborates what the present writer has said of the nature of the
lights seen skimming across the zenith, and across each other, and
the deduction which he has thence made, that the luminous appearances
in the zenith are the summits of those very pillars of which the
bases are on or below the horizon. The clear and calm weather which,
on the shores of the Icy Sea, commonly follows the appearance of
the Aurora is, in some degree, in concord with the phenomena of its
recent appearance in London; where, without any material change
in the temperature, a succession of clear, calm, and bright days
supervened, within a day or two of the Aurora. As to the hissing,
crackling, or rushing noise, which is said to accompany the Aurora
in the more northern regions, and which has sometimes been compared
to that of the furling and [p415] unfurling of flags, there is
nothing difficult, (knowing what we do of the noise of winds and of
thunder,) in admitting its probability, unless what may arise from
the consideration, that the noise might, or might not, be expected
to be heard, where-ever the phenomenon is to be seen. But the most
striking and important truth, communicated in the foregoing account,
is that which we cannot but rigorously infer from the collective
testimony of two very distinct descriptions, which is afforded in two
of the concluding sentences. It consists in that real _infrequency_,
as well in the Northern, as in the Southern Hemisphere, of the
appearance of the Aurora; an _infrequency_ the knowledge of which is
so essential to the true history of the phenomenon, and therefore
to its true philosophy, and consequently to much of the history and
philosophy of nature at large;—an _infrequency_ which the present
writer has given notice of above, as a proposition for which, in
dissent from all received authorities, he will contend; and upon the
opposite account of which matter, in the general account quoted,
he has already requested the reader to suspend his judgment. It is
obvious that, as a natural phenomenon, an Aurora Borealis, which,
though _constantly_ experienced in the more Northerly regions, is but
rarely observed in the more Southern; that is, an Aurora Borealis
which, though familiar to the Samoiede, the Laplander, and even
the Shetlander, is an extraordinary, and a terrific, or at least a
marvellous event, to the Italian, the Frenchman, and even to the
Englishman; it is obvious, that such an Aurora Borealis, _constant_
in its occurrence a little further to the Northward, and almost
the solitary spectacle of a generation a little further to the
South, is, as a natural phenomenon, a very different thing from an
Aurora Borealis which, though far enough to the South, sufficiently
frequent in comparatively trivial magnitudes and lustre, is seen,
either in the South or in the North, in its greatness, and in its
splendour, but yet rarely, and with, perhaps, almost equal rareness;
it is obvious that, as natural phenomena, and not less so as sights
connected by mankind with their own fortunes, the two things now
described are exceedingly unlike as matter of history, and equally so
as matter of philosophy. If we are simply to record the occurrence,
it is one thing to speak of a phenomenon [p416] which, in the South,
is seen only at long intervals, while it is a “constant attendant”
in the North; and another thing to speak of that which, whether
in the South or in the North, is equally rare, and equally out of
the “constant” course of nature. If we are to write the history of
nature, it is one thing to relate, that such phenomena, or rather
others, infinitely more splendid, more terrific, or more marvellous,
than that which was witnessed in London, in the month of September
in this year, or in the same month some three-and-twenty years ago,
or else some six-and-thirty, and, to judge by experience, is not
to be looked for, in the same city, during twenty or thirty years
again;—it is one thing to relate that, in the Shetland Islands,
such a spectacle is a “constant attendant of clear evenings,” and
another thing to relate, that though, perhaps, on clear evenings,
in the Shetland Islands, some small displays of the Aurora are
not unfrequently perceived, yet, that such an exhibition as has
recently been witnessed in London, and still more, such as, more
effulgent, and more extended, and more vigorous, and even coloured
by the atmosphere into the terrific;—that those exhibitions, in
short, of which our naturalists and men of science would persuade
us, that, while beheld nightly by those of the North, they are known
to us by very faint examples alone;—those exhibitions,—that those
extraordinary examples of the brightness and vigour of the Aurora—are
as rare, or almost as rare, not only in the Shetland Islands, but
in Iceland, and on the shores of the Icy Sea, as in the streets of
London themselves! It is obvious, too, that if we are to speak of
this phenomenon philosophically, if we are to attempt to explain its
origin and use,—its source in the natural elements, and its office in
the natural economy; here, too, the solving of this question of the
_frequency_ or _infrequency_, the _constancy_ or the _inconstancy_,
of these mighty exhibitions, even in the North, and under the Pole
itself, is matter of foremost importance. And what is the testimony,
upon these heads, which is borne by the accounts collected by Gmelin?
Is the Northern Light of the German naturalist, the apparently
constant attendant of clear evenings, even in the countries between
the Lena and the Yenesei? Is the spectacle, and the atmospherical
hurley, which seems to rush over the [p417] hunting-grounds of
the hunters and their dogs, and which frightens the very dogs, and
pins them to the ground till it is passed, or has seemed to pass;
is this the “constant attendant of clear evenings,” or, is it a
prodigy so uncommon as to defy familiarity? But, if this evidence is
insufficient, let us look to what is said of its influence, in these
countries, on the subsequent state of the atmosphere. So far from the
Aurora being an attendant or follower of clear evenings, it seems
that clear evenings follow the Aurora! It is said, that after its
occurrence, clear and calm weather is customary to follow; and, here,
the expression itself is implicative of the rarity of the occurrence.
If it were constant, how should this result come to be noticed;
and, indeed, if the Aurora Borealis were the constant attendant of
each twenty-four hours, and if clear weather were usually in the
train of the Aurora Borealis, how could it ordinarily happen, that
there should be any thing else than clear weather, in the countries
visited by the Aurora, or any foul weather for the Aurora to dispel?
Yet, such is the established prejudice concerning this supposed
frequency of the more powerful displays of the Aurora in the climates
further to the North than our own, that a writer, quoting the very
statement above, absolutely prefaces it with the remark, that
Gmelin, in pointed terms, speaks of the Aurora as “frequent,” as
well as “very loud,” “in the North-eastern parts of Siberia[125]!” A
simple perusal, in the meantime, is sufficient to show, that Gmelin
says nothing affirmative as to its _frequency_; while a slight
consideration of the facts which he adduces must satisfy us, as no
doubt they satisfied Gmelin himself, that the occurrence, even in
Siberia, is actually _infrequent_!
* * * * *
XI. In reference, however, as well to the image presented above, of
“a vast tent expanded in the heavens, glittering with gold, rubies,
and sapphires;” as also to many less ambitious and figurative
descriptions of the spectacle of the Aurora Borealis, (not excepting
that indicted by himself,) the author is anxious to suggest a caution
against the too exaggerated conception of the realities intended.
Words, [p418] upon such occasions, are rarely more than imperfect
pictures, presenting but feeble likenesses, and either deficient or
excessive in the amount of beauty, or of the reverse, of whatever
kind, which they attempt to copy from their originals; and the
inconvenience is seriously great, whenever the object portrayed is
wholly strange to the mind before which it is placed. The imperfect
power, both of words and written characters, to convey precise, and
sometimes even tolerable ideas, of the objects, either sensible or
abstract, which they are intended to represent, and the superior
intelligibility so often belonging to diagrams or figures, or other
resources of the art of drawing, (the primitive, and, for so many
purposes, the most instructive mode of writing[126],) would have
led the present writer, had time permitted, to endeavour, as often
as possible, to elucidate by such means the several parts of the
foregoing observations; but which means, at last, and in reference to
the actual phenomena of the Aurora, would necessarily fail to convey
the due, and yet no more than the due impression, to such as are
wholly without its ocular acquaintance. We are little aware how much,
upon ordinary occasions, our understanding of words heard or read is
assisted by our previous knowledge of the sensible objects, or of
the acquired notions, to which they refer; and the examples would be
endless, of the sensible objects preposterously misconceived, as well
as the propositions made false or ridiculous, through the frequent
inadequacy of words to communicate truths entirely new [p419] to the
disciple. Even the history of opinions concerning the Aurora Borealis
itself, might be cited upon this very point.
The ordinary and natural resource, in such circumstances, is
comparison; but even comparison has been the source of great and
endless errors of description. Of the degree of resemblance proposed
between the known and the unknown, there is no common measure for
the minds of the hearer and the listener, and the point or points
of comparison intended by the first must often be mistaken by the
second; or, if reference is made to a similitude under one aspect,
the imagination conceives a resemblance also under another: thus,
if it is said, that an unknown animal is as _large_ as a horse,
the idea of the _figure_ also of a horse, is apt to be attached. A
modern English work of science premises, upon the subject of the
Aurora Borealis, that its appearance is so well known as to render
description needless. It is true that the work referred to is
printed in the Northern part of the island, where the phenomenon is
doubtless more familiar than in the Southern; but, in the foregoing
pages themselves, it has, perhaps, been demonstrated as probably
certain, that if it is any where sufficiently known to render
description trite for the common eye, it has at least never hitherto
been described with sufficient precision for the aid of speculative
research. To attempt to explain its _cause_, and to relate its
entire history, its _appearance_ must first be either observed or
described with accuracy; and we have seen, above, that some of the
most scientific reasonings which have hitherto been offered as to
the former, are wholly inapplicable to the true peculiarities of the
latter.
Considered simply as a visual object, and as a meteor differing
from all others, and especially from all other luminous meteors,
in this, that its duration extends to hours, if not to days and
months; the only resemblance, perhaps, that can be suggested, is to
that description of lightning which is called _heat-lightning_, the
frequent companion of our summer-evenings. But, here, the similitude
is inexpressibly feeble; since heat-lightning has nothing, either of
the splendour, the volume, or the beauty of the Aurora; and since
the light of the latter, however mobile, varied, and, from time to
time, increased and diminished in itself, is yet, as to general
effect, continuous and [p420] steady. There remains, then, but to
compare the phenomenon of the Aurora with the rising or the setting
Sun. In both of these latter, as in the Aurora, the light is in
the horizon, and that light is shot upward, perpendicularly, or
obliquely, toward the zenith or toward the right and left; and both
of these, like the Aurora, are more or less constantly attended with
a variety of colouring, similar in hue if not in depth, and always
beautiful, and often gorgeous. With the _Sun_, and with the beams
of the Sun, ancient description, in point of fact, has confounded
the _Aurora Borealis_, to the degree, perhaps, of giving origin to
some of the ancient and poetical descriptions of the Sun, utterly
inappropriate and inexplicable as understood of that day-star, but
easily recognised in the Aurora; yet the dissimilitudes, at last, are
numerous and great! Of the essential difference of figure, both as to
the _beams_ of the Sun, and the _beams_ of the Aurora, in severalty,
and of the inevitable difference of indication of which, as to their
nature, mention has been already made; and also as to the general
or collective figure of the beams of the Aurora, as contrasted with
that of the rising, or of the setting Sun. The next point is the
homogeneity of colour in the beams of the Sun, however the apparent
colour may vary, as it is seen to do, from horizontal stratum to
horizontal stratum, from the horizon to the zenith, according to the
varied density of the medium between the light and the eye of the
spectator. The light, upon the other hand, of the beams of the Aurora
is heterogeneously coloured in itself, and is so displayed; and
not, therefore, varied as the beams ascend from horizontal stratum
to horizontal stratum, or as crossing all the beams together, but
found in each particular beam itself, and attending its direction,
whether vertical or inclined, and whether rectilinear or curved.
Waiving, then, any comparison in detail, between the phenomena of
the Aurora, and the phenomena of the rising or of the setting Sun,
but admitting that, to a certain degree, all are alike vast in
dimensions, splendid in light, rich in colour, and durable upon the
eye; there is still nothing else to be subjoined, than that, at least
with reference to vastness of dimension and magnitude of the volume
of light; to the quantity of light diffused; and to the richness and
gorgeousness of [p421] the attendant colouring; there can be little
risk, in the assertion that, vast, and splendid, and beautiful, and
rich, and gorgeous, as, when seen in the most favourable situation,
and under the most favourable circumstances, the Aurora may be, it
is, at last, but insignificant, when compared, for those features,
to the vastness, the splendour, the beauty, the richness, and the
gorgeousness, more or less, from day to day, displayed in the rising
or the setting of the Sun; and, that for chaster beauty, and even for
amount of light diffused, it is not even to be likened to the silver
Moon! As a substitute, too, for either, or for both, the Aurora, in
the regions of cold and night, may justly demand the admiration and
the blessing of mankind; and, in regions cold and inclement, its
rarity, not unaccompanied by beauty, by grandeur, and sometimes even
by the terrible in appearance, may well invite the gaze and fix the
attention of beholders; but, considered along with the light of the
luminaries of heaven, its claims reduce themselves in quality, though
certainly not in degree, to a level with those of an artificial
lustre; and we almost repeat, in reference to the light of the
Aurora, as compared with that of the Sun, or even of the Moon, what
the poet has said in reference to the lights of our chambers:—
“Who but rather turns
To heaven’s broad beam his unconstrained eye,
Than to the glimmering of a waxen flame?”
The Moon, in the meantime, inferior as she is to the Sun, has
been “blessed,” from age to age, for her “useful light;” and the
“useful light” of the Aurora, also, has its claims to “blessing.” It
co-operates with the Sun, the Moon, and with other agents of nature,
to make, not merely the Polar regions of the earth, but the entire
globe of the earth, fruitful, at once, and habitable[127]! [p422]
* * * * *
XII. In a succeeding paper, the author may possibly submit to the
consideration of his reader, the particular and novel hypotheses
which he has allowed himself to form, as to the _substance_,
_causes_, and _effects_ of the Aurora; hypotheses partly dependent
upon those _facts in its natural history_, which, above, have been
almost the exclusive objects of attention. At present, the leading
particulars of the _natural history_ of the phenomenon, which it has
been attempted either to bring or to fix in view, are these:
1. That the Aurora is a phenomenon observed both in the Northern and
Southern Hemispheres.
2. That, in either hemisphere, it is observed in the general
direction of the corresponding _pole of the earth_.
3. That, in the Northern Hemisphere, on the shores of the Icy Sea, or
at the furthest distance north, its situation is still observed to be
the northward.
4. That, in the Southern Hemisphere, it has been observed to the east
of the South Pole, and in the Northern, to the east and west of the
North Pole.
5. That, upon the late occasion, the place of its columns, during the
exhibition, was observed to change from the west of north to the east
of north; but, so as always to have the north for the apparent centre
of its strength.
6. That, in the Arctic regions, the appearance of the Aurora is said
to be usually followed by clear and calm weather.
7. That the appearance of the Aurora Borealis is no wise peculiar
to the winter solstice, but has been observed in each of the eight
months of September, October, November, December, January, February,
March, and April, and may be regarded, therefore, as coincident
with the Arctic winter; and that the appearance of an Aurora in the
Southern Hemisphere, in the month of February, or beginning of the
Antarctic winter, as observed during the voyage of Captain Cook, in
the year 1773, is [p423] consistent with the persuasion, that the
Aurora _Australis_, in its turn, is a phenomenon of the Austral or
Antarctic winter.
8. That _considerable_ or powerful displays of the Aurora are
infrequent, even in the extreme Polar regions; and that it is _very
considerable_ or powerful displays alone, which make themselves
visible in the lower latitudes, north or south of the equator.
9. That no appearance belongs to the Aurora itself, but that of its
coruscations, columns, spears, or streamers; and that all colours,
therefore, or coloured figures, not belonging to the coruscations,
but coincident in their appearance, are to be regarded only as
reflections or refractions of light, derived from the coruscations by
the clouds which happen to cover the sky.
10. That the colours, or coloured light, proper to the Aurora, or
seen in the columns or coruscations themselves, are varied from
column or coruscation to column or coruscation, and severally
continued in the direction, and throughout the length or height, of
each.
11. That, in the late example, the columns or coruscations situate
in the due north, or apparent centre or focus of the phenomenon,
exhibited a light at least comparatively white; and that the
variation, from white to colour, had an apparent relation to the
comparative remoteness of each column or coruscation from the column
or coruscation in the central north.
12. That the direction or position of the columns or coruscations of
the Aurora, are so far from being uniformly convergent toward the
zenith, or uniformly vertical, or from the horizon to the zenith,
that, in the late example, they _did not converge_ toward the zenith,
but, contrariwise, _diverged_ from it; spreading themselves like the
sticks of a fan, or like stalks in a flower-basket.
13. That the columns or coruscations of the Aurora are not uniformly
rectilinear in their figure; but that, in the late example, those
on the north-eastward were curved outwardly, or “bent sideways,” as
described in the appearance of the columns or coruscations of an
Aurora seen in the Southern Atlantic, during the voyage of Captain
Cook, in the year 1773. [p424]
FOOTNOTES:
[120] Literary Gazette, Sept. 29, 1827.
[121] “PENCELLS.—Pencills, or flagges for horsemen, must be a
yard and a halfe long.” Harleian MSS., cited in an interesting
and valuable essay on the “Banners used in the English army, from
the Conquest to the reign of Henry VIII.” By N. H. NICOLAS, Esq.,
F.S.A—_Retrospective Review_, Oct. 1, 1827.
“The Pensell, or Pennoncelle, was the diminutive of the Pennon,
being a long narrow flag.”—MEYRICK’S ANCIENT ARMOUR.
“STREAMER.—A Streamer shall stand in the toppe of a shippe, or in
the forecastle, and therein be put no armes, but a man’s conceit or
device, and may be of the lengthe of twenty, forty, or sixty yards;
and it is slit, as well as a guydhomme or standarde.”—HARLEIAN MSS.
An item, in a bill of parcels, charged to the Earl of Warwick, in
1437, consists of “a great Stremour for the Ship, of xl yerdis
lenghth, and viij yerdis in brede.”—BANNERS USED IN THE ENGLISH
ARMY, &c.
[122] Meteorological Journal, Literary Gazette, Sept. 29th.
[123] Literary Gazette, as above.
[124] _Encyclopædia Britannica_. Art. Aurora Borealis.
[125] Encyclopædia Britannica.
[126] The individual, social, and political importance of making
the _art of drawing_ a branch of general education, is a subject
which the author can never cease to urge upon the attention of his
fellow-countrymen, and of all the civilised world. It is more than
ten years since he first endeavoured to lead the public eye to its
regard. In England, and with a view to the subsistence of a large
and always increasing population, it is an EDUCATION IN THE ARTS
which is the great want; and the _art of drawing_, besides being
the assistant of all _knowledge_ whatever, is peculiarly so of all
other _arts_ than itself, or of all other works of the _hand_. A
recent Sermon, by the Lord Bishop of Bath and Wells, preached at
Wells, for the benefit of the Diocesan National Schools, bears ample
testimony to the deficiency, and even the dangers, to the poor not
less than to others, in all the present popular education; and, so
far, therefore, to the soundness of the author’s principles, and
to the fitness of his remedy. His own design, however, is not only
to remedy an evil arising from the present practice, but also to
produce an independent good; and, not merely to aid the poor, nor
merely to promote the political welfare of this kingdom, but to
increase the resources, physical and intellectual, of all classes,
and to promote the welfare of the whole world.
[127] The author has an opinion, that among the “agents of nature,”
for equalising the temperature of the surface of the globe, is to
be reckoned, not only the Northern and Southern Lights, but the
entire Ocean; and that this agency is the immediate object aimed at
in the existence of this last, as one body of water surrounding the
entire globe. His evidence consists in geographical, hydrographical,
meteorological, and physiological facts, as also in the apparent
reason of the case. He supposes, in consequence, a perpetual
circulation of the waters of the sea, longitudinally round the
globe, or from North to South, and from South to North again; and
the result of Captain Parry’s late attempt to reach the Arctic
Pole, as also some of the facts which have transpired respecting
Captain Franklin’s late land expedition, appear to confirm his
theory, according to which the physical use, or final cause, of
the existence of the Ocean has never previously been understood.
His theory affects the question of the North-west Passage, which
latter object he suspects to have never yet been pursued in the true
direction; even the discoveries of Captain Parry appearing to him to
have fallen short of ascertaining the communication with the Polar
Sea by the channel of Davis’s Strait.—Some introductory observations
upon this subject have been already made in an article in the New
Monthly Magazine for October, 1826, (vol. xvii. p. 371.)
_Proceedings of the Royal Society_.
The anniversary meeting of the Royal Society for the election of a
president, and other officers, was held as usual at Somerset House,
on Thursday, the 30th of November, being St. Andrew’s day.
Till within a few days of the election, it was generally understood
that the Rt. Hon. Robert Peel was a candidate for the chair; in
consequence, however, of that gentleman having declined, Davies
Gilbert, Esq., M.P., was put in nomination, and was almost
unanimously elected the President of the Royal Society.
The late secretaries, Messrs. Herschel and Children, having resigned
their respective offices, Dr. Roget and Captain Sabine were nominated
in their places, and were duly elected.
The accession of Mr. Gilbert to the chair having rendered vacant the
office of Treasurer, Major Kater was elected in his place.
The following council was elected, to continue in office until St.
Andrew’s day, 1828.
Davies Gilbert, Esq.
Major Kater.
Dr. Roget, M.D.
Captain Sabine, R.A.
Dr. Wollaston, M.D.
Dr. Fitton, M.D.
Dr. Young, M.D.
Dr. Paris, M.D.
Dr. Prout, M.D.
Dr. Goodenough, D.D.
Dr. Buckland, D.D.
J. W. Croker, Esq.
Lord Colchester.
Sir E. Home, Bart.
Sir H. Davy, Bart.
John Pond, Esq.
Capt. F. Beaufort, R.N.
Francis Baily, Esq.
John Guillemard, Esq.
[p425]
In consequence of having been elected President _pro tempore_ by the
council, (the chair having been vacated some weeks previous to the
general election,) the duties of the office were performed by Mr.
Gilbert, on occasion of the present anniversary. After having read
over the list of members admitted, and of those deceased during the
last year, he proceeded to announce the disposal of the Royal and
Copley Medals, as awarded by the votes of the council.
Of the Royal Medals, one was awarded to Sir H. Davy, and the other to
Professor Struve. Of the Copley Medals, one was given to Dr. Prout,
and another to Lieutenant Forster. On this occasion Mr. Gilbert
pronounced an eulogium upon the respective receivers of the medals;
and, in adverting to the labours of the several individuals, he
justified the decision of the council, in bestowing upon them these
marks of distinction, in a learned and eloquent discourse.
_Proceedings of the Horticultural Society_.
_September_ 4th.
A paper by Mr. Lindley was read upon the new hardy plants which had
flowered in the Society’s garden; among them a number of new shrubs
were mentioned, which appeared likely to prove acquisitions to the
public. A thermometer was exhibited by Mr. Bregazzi, of Derby,
for ascertaining the temperature of bark-beds. It consisted of a
thermometer enclosed in a shaft of copper with a wooden handle, and
a door in its side, by which the temperature can be ascertained with
precision. It is needless to point out the superiority of this plan,
over the common mode of determining this very essential point, by
feeling of a stick previously stuck in the bed; the sensation of heat
when the stick is grasped in the hand will obviously depend in a
great degree upon the temperature of the hand itself. As usual, there
was an extensive display of all the choicest flowers and fruit of the
season. One hundred and seventy-two subjects of this description were
placed upon the table. Among the flowers, the most remarkable was
a new hardy climber from Mexico, with deep purple blossoms studded
[p426] with glittering green glands, called Maurandya Barclaiana;
among the fruit was a fine specimen, from Lord Grantham’s garden, of
the Papaw, a tropical fruit never ripened in England before.
_September_ 18th.
The exhibitions of this day were chiefly confined to a display of
Dahlias, which for magnificence exceeded any thing of the kind we
ever witnessed before. The large meeting-room was filled with masses
of the richest and most lively colours. In the whole, eight hundred
and fifty-one varieties were shown, among which the finest were from
the garden of William Wells, Esq., of Redleaf; but where all are so
excellent, it is almost invidious to particularize. The time will
be remembered by many of our readers when gardens in the autumn
contained little besides marigolds, sun-flowers, and sweet-peas; by
the aid of dahlias and chrysanthemums the autumn has now become the
liveliest season of the year, and the beauty of the flower-garden
is only destroyed by the severest of the winter frosts. Among the
grapes upon the table was a remarkably excellent yellow-berried kind,
from Portugal, from the garden of Mr. Holford, of Hampstead, which
was quite new to this country. Apples, nectarines, peaches, and
pine-apples abounded.
_October_ 2nd.
Among the flowers was a fine bunch of ranunculuses, from Mr. Groom,
of Walworth, a rare sight in October; they were obtained by having
been planted in July and carefully protected by tulip-shades when
coming into flower. The season for softer fruits being nearly over,
pears and apples formed the chief display; of these a vast number,
upwards of one hundred and eighty of the latter, were upon the
table: the Blenheim orange, or Woodstock pippin, pomme gris, scarlet
nonpareil, courtpendu plat, golden reinette, and packhorse apples;
and Chapman’s, Marie Louise, and brown beurré pears, appeared to
us to excel all their rivals. The famous gloux morceau and beurré
d’Aremberg pears were also exhibited, but were not ripe. [p427]
_October_ 16th.
The first number of a new periodical work, called the _Pomological
Magazine_, consisting of coloured figures of the fruits cultivated
in Great Britain, was placed upon the table. Among the apples were
specimens of a variety sent from England to Connecticut, in the year
1636, and reimported from America within a few years. It proved to
be a kind not known at the present day in this country, but still
cultivated in France. In the gardening books of the sixteenth and
seventeenth centuries it is mentioned under the name of the haute
bonté. The specimens exhibited served to disprove the opinion that
many of the American apples are European kinds altered by climate;
these, although the produce of trees which have been growing in
America for nearly two hundred years, differed in no respect from
French samples exhibited at a subsequent meeting of the Society.
_November_ 6th.
An excellent paper was read upon the method of cultivating horse
radish, in Denmark. The roots are cut into slips, and planted
_horizontally_, the lower end inclining a little upwards, and the
crown of the plant hanging over the alleys, by which the beds are
separated. From time to time the roots are uncovered, and all the
_lateral_ fibres are carefully removed, by which the size and length
of the roots are much increased. The place hitherto occupied by
dahlias, was now taken by Chinese chrysanthemums, of which a large
number, consisting of twenty-two different varieties, was exhibited
at the bottom of the room.
_November_ 20th.
Cuttings of the fine new Portugal grape, of which fruit was exhibited
on the 18th of September, were distributed to the members present.
A few dahlia flowers still showed themselves, notwithstanding the
unusual severity of some early frosts, and the room was crowded with
chrysanthemums. The gloux morceau and beurré d’Aremberg pears were
tasted, and found to retain the station which has been assigned to
them at the head of all known varieties. [p428]
ASTRONOMICAL AND NAUTICAL
COLLECTIONS. For Jan. 1828.
i. EPHEMERIS _of the periodical_ COMET _for its Return in 1828,
computed with the consideration of a_ RESISTING MEDIUM. _By_
Professor ENCKE.
_Elements_.
Mean anomaly 1829 Jan.9.72, mean time at Paris, = 0° 0′ 2″.83
Mean daily sidereal motion = 1069″.87572.
° ′ ″
Longitude of the perihelion = 157 17 26.2} Mean Equinox
Ascending node = 334 28 47.1} 1829 Jan.9.72.
Inclination = 13 20 47.9
Angle of the eccentricity = 57 38 25.2
_Ephemeris_.
Mean Parisian time, 1829. A. R. Decl. N. Log. Dist.
° ′ ″ ° ′ ″ ☉ ⊖
Aug. 23.3 26 50+.. 22 42+.. .34603 .19571
24.3 50... 52 .34411 .18983
25.3 49... 23 1 .34217 .18390
26.3 48... 10 .34022 .17791
27.3 46... 19 .33825 .17187
28.3 44 29 .33626 .16577
29.3 41 38 .33425 .15962
30.3 37 47 .33222 .15341
31.3 33 56 .33017 .14714
Sept. 1.3 28 24 6 .32810 .14082
2.3 22 15 .32602 .13444
3.3 16 24 .32392 .12801
4.3 9 34 .32180 .12153
5.3 1 43 .31966 .11499
6.3 25 53 52 .31749 .10839
7.3 44 25 2 .31531 .10174
8.3 34 11 .31310 .09504
9.3 23 20 .31087 .08829
10.3 11 29 .30862 .08148
11.3 24 58 38 .30635 .07462
12.3 45 47 .30406 .06771
13.3 30 56 .30174 .06075
14.3 15 26 5 .29940 .05375
15.3 23 58 14 .29704 .04670
16.3 41 23 .29465 .03961
Sept. 17.3 23 22+.. 26 32+.. .29224 .03247
18.3 2 41 .28980 .02529
19.3 22 41 49 .28733 .01806
20.3 19 58 .28484 .01080
21.3 21 56 27 6 .28232 .00350
22.3 32 14 .27978 .99617
23.3 6 22 .27721 .98881
24.3 20 39 30 .27461 .98142
25.3 10 37 .27198 .97400
26.3 19 40 45 .26933 .96656
27.3 9 52 .26665 .95910
28.3 18 37 58 .26393 .95162
29.3 3 28 5 .26118 .94413
30.3 17 27 11 .25840 .93663
October 1.3 16 50 17 .25559 .92913
2.3 16 11 22 .25275 .92164
3.3 15 31 27 .24987 .91415
4.3 14 49 32 .24696 .90668
5.3 5 36 .24402 .89923
6.3 13 20 39 .24104 .89181
7.3 12 34 42 .23803 .88442
8.3 11 45 44 .23498 .87707
9.3 10 55 46 .23189 .86976
10.3 4 47 .22876 .86251
11.3 9 10 47 .22559 .85532
12.3 8 15 46 .22238 .84820
13.3 7 19 45 .21913 .84116
14.3 6 21 43 .21584 .83421
15.3 5 21 39 .21251 .82735
16.3 4 20 35 .20913 .82059
17.3 3 18 30 .20570 .81394
18.3 2 14 24 .20223 .80741
19.3 1 9 17 .19871 .80101
20.3 0 3 9 .19515 .79474
21.3 358 56 0 .19154 .78861
22.3 357 47 27 49 .18787 .78263
23.3 356 38 38 .18415 .77681
24.3 355 28 25 .18038 .77116
25.3 354 17 11 .17656 .76568
26.3 353 5 26 56 .17268 .76037
27.3 351 53 40 .16874 .75525
28.3 350 40 22 .16475 .75031
29.3 349 27 4 .16069 .74557
30.3 348 14 25 44 .15657 .74102
31.3 347 1 23 .15239 .73668
Nov. 1.3 345 47 1 .14814 .73253
2.3 344 34 24 38 .14382 .72858
3.3 343 21+.. 24 14+.. .13943 .72483
4.3 342 9 23 49 .13497 .72128
5.3 340 56 23 .13044 .71793
6.3 339 44 22 56 .12583 .71477
7.3 338 33 29 .12114 .71180
8.3 337 23 0 .11638 .70902
9.3 336 13 21 31 .11153 .70642
10.3 335 4 1 .10660 .70399
11.3 333 56 20 31 .10158 .70172
12.3 332 48 0 .09647 .69961
13.3 331 41 19 29 .09126 .69765
14.3 330 36 18 57 .08595 .69583
15.3 329 31 25 .08055 .69415
16.3 328 27 17 52 .07505 .69258
17.3 327 23 19 .06944 .69113
18.3 326 21 16 46 .06372 .68979
19.3 325 19 12 .05788 .68854
20.3 324 18 15 39 .05193 .68738
21.3 323 18 5 .04585 .68630
22.3 322 19 14 31 .03965 .68529
23.3 321 20 13 56 .03331 .68434
24.3 320 21 22 .02684 .68345
25.3 319 23 12 47 .02022 .68261
26.3 318 26 12 .01346 .68182
27.3 317 28 11 37 .00655 .68106
28.3 316 31 2 .99948 .68034
29.3 315 34 10 26 .99225 .67964
30.3 314 37 9 50 .99484 .67897
December 1.3 313 40 9 14 N. .97726 .67833
2.3 312 43 8 37 .96949 .67772
3.3 311 45 8 0 .96153 .67713
4.3 310 48 7 23 .95336 .67657
5.3 309 49 6 45 .94499 .67605
6.3 308 50 6 6 .93640 67556
7.3 307 50 5 27 .92759 .67513
8.3 306 49 4 47 .91854 .67476
9.3 305 47 4 6 .90924 .67446
10.3 304 44 3 24 .89969 .67425
11.3 303 40 2 42 .88987 .67415
12.3 302 34 1 58 .87978 .67418
13.3 301 27 1 13 .86939 .67437
14.3 300 18 0 27 N. .85870 .67475
15.3 299 7 0 19 S. .84770 .67536
16.3 297 54 1 8 .83638 .67623
17.3 296 40 1 58 .82474 .67742
18.3 295 23 2 49 .81276 .67896
19.3 294 5 3 42 .80042 .68091
Dec. 20.3 292 45+.. 4 36+.. .78771 .68333
21.3 291 23 5 32 .77465 .68627
22.3 289 59 6 29 .76123 .68980
23.3 288 34 7 27 .74746 .69399
24.3 287 8 8 27 .73334 .69889
25.3 285 42 9 27 .71890 .70456
26.3 284 15 10 28 .70416 .71107
27.3 282 48 11 30 .68917 .71845
28.3 281 23 12 32 .67399 .72677
29.3 280 0 13 34 .65871 .73604
30.3 278 39 14 36 .64342 .74629
31.3 277 21 15 37 .62830 .75750
1830 Jan. 1.3 276 9 16 37 .61348 .76969
2.3 275 2 17 36 .59920 .78278
3.3 274 1 18 33 .58572 .79670
4.3 273 9 19 29 .57332 .81139
5.3 272 25 20 22 .56231 .82673
6.3 271 50 21 12 .55304 .84259
The opposition to the sun will be 1828, Oct. 12.34: while its light
is weak, it may be observed on or near the meridian.
On the 10th of Nov. 1828, its distance from the sun will be the same
as at the time of its discovery in 1818, and it will be considerably
nearer to the earth; and on the 21st of December, its position with
respect to the sun will be the same as at its last observation
in 1819; and with respect to earth, its situation will be more
advantageous. The 1st of January, 1829, it will set with the sun.
It follows, that the most advantageous time for seeing it will be
during the whole of November, and the first 25 days of December.
It will scarcely be seen before the end of September, as it has
heretofore never been observed more than two months before the time
of its perihelion, and even in the dark winter nights will scarcely
be visible more than 14 or 15 weeks before that period. After the
perihelion it will not be visible in these parts of the world.
ii. _Elementary View of the_ UNDULATORY _Theory of Light_. _By_ Mr.
FRESNEL.
[Continued from the last Number.]
In order to complete the explanation of the conditions necessary for
the formation of the fringes, it remains to show why a small luminous
point must be employed in experiments on diffraction, and not an
object of any considerable dimensions. If we resume the case of the
interior fringes of the shadow of [p432] a narrow body, it will be
easy to apply similar arguments to other cases of diffraction.
The middle of the central band, which is always formed by the
simultaneous arrival of rays, which depart at the same instant from
the luminous point, must be found in the plane drawn through this
point, and the line bisecting the narrow body: because, since every
thing is symmetrical on each side of this plane, the rays which unite
in it must have passed through equal routes on each side, and must
consequently arrive at the same instant, unless they have passed
through different media, which is not the case to be considered at
present. The situation of the middle stripe being determined, that
of every other stripe must also be determined accordingly. Now it
is evident that if the luminous point should change its situation a
little, and be moved to the right, for example, the plane, which has
been supposed, would incline to the left, and would carry with it all
the fringes which accompany the middle stripe. And if, instead of
supposing motion, we suppose the luminous point to become of sensible
dimensions; the integral points of which it is composed will each
produce a group of fringes, and their situations will be so much the
more remote as the luminous object is larger; and ultimately, if its
size is sufficiently increased, they will extinguish each other and
disappear. This is the reason that, when the rays cross each other at
sensible angles, as in all the phenomena of diffraction, it becomes
necessary to employ a very fine luminous point, in order to discover
their mutual influence: and the point must be so much the finer as
the angle formed by the rays is greater.
However minute the luminous point may be, it is always composed, in
reality, of an infinite number of centres of oscillations, and it is
of each of these centres that we must understand what has been said
of a luminous point. But as long as they are very near to each other
in comparison with the breadth of the fringes, it is obvious that the
different groups of fringes which they produce, instead of mixing
with each other in a confused manner, will be superposed almost
exactly, and instead of extinguishing, will co-operate with each
other. [p433]
When the two systems of waves which interfere are parallel, the
interval which separates their corresponding points must remain the
same for a great portion of the _surface of the waves_, that is to
say, in other words, the fringes will become almost infinite in
breadth, so that a very considerable displacement of the centre of
undulation will cause very little difference in the agreement or
disagreement of their vibrations. And in this case it is no longer
necessary to employ so small an object in order to perceive the
effects of their mutual influence.
If the coloured rings, which are produced by the interference of two
systems of undulations nearly parallel, exhibit, like the fringes,
and often within a very short distance, alternations of dark and
bright stripes; this circumstance depends entirely on the want of
uniformity in the thickness of the plate of air interposed between
the glasses, which causes a variation of the difference of the routes
of the rays reflected at the first and at the second surface of this
plate, of which the mutual interference produces the bright and dark
rings.
We shall readily be able, to understand why the luminous rays,
although they always exert a certain influence on each other, exhibit
it to the eye so seldom, and in cases so much limited, if we consider
that it is necessary, for such an exhibition, first, that the rays
concerned shall have been derived from a common source; secondly,
that the difference between their paths shall amount to a limited
number of undulations only, even when the light is as homogeneous
as possible; thirdly, that they shall not intersect each other at
too great an angle, because the fringes would become so small as to
be invisible even with the assistance of a strong magnifier; and
fourthly, unless the rays are nearly parallel, that the luminous
object should be of very small dimensions, and the smaller in
proportion as the inclination of the rays is greater.
It has been thought necessary to insist so much at length on the
theory of interferences, because of its numerous applications to the
calculation of the most interesting of the laws of optical phenomena.
These considerations may perhaps appear at first somewhat delicate
and difficult of comprehension, notwithstanding the minuteness of the
[p434] explanation; but with some reflection it will be found that
nothing can be simpler than the principles on which they are founded,
and their application will soon become familiar to the imagination.
In order to complete the bases of the general theory of diffraction,
it remains for us to consider the principle of Huygens, which appears
to be a rigorous consequence of the system of undulations.
The principle may be thus expressed: _The vibrations of a luminous
undulation, in each of its points, may be regarded as the result of
the elementary motions which would be transmitted to that point, at
the same instant, from all the points of the undulation, considered
separately, as they existed in any one of its earlier situations_.
It is a consequence of the principle of the co-existence of small
motions, that the vibrations, produced at any point of an elastic
fluid, by several agitations, are represented by the result of all
the velocities belonging to that point at the same instant, as
derived from the different centres of the undulations, combined
according to the laws of motion, whatever may be the number and
situation of the centres, and whatever the periods and nature of the
undulations. This general principle is applicable to every particular
case. We may suppose the agitations infinite in number, of the same
kind, simultaneous, and taking place in contiguous points of a
plane or a spherical surface: it will also be convenient to suppose
the motions of the particles to take place in the same direction,
perpendicular to the surface, their velocity being proportional to
the condensation of the medium, and none of them retrograde in their
direction. In this manner a derivative undulation will be produced by
the union of these agitations, and the principle of Huygens may be
truly applied to such a propagation. [This may be called a rigorous
consequence of the system, but it can scarcely be considered as a
proposition mathematically demonstrated: and the fundamental law of
Huygens must perhaps be assumed as an axiom or a phenomenon. TR.]
The intensity of the primitive undulation being uniform
throughout the surface, it results from this “theoretical” [p435]
consideration, as well as from other reasoning, that the uniformity
will be preserved throughout the progress of the undulation, unless
any part of it be intercepted or retarded; because the result of the
elementary motions, which have been mentioned, will be the same for
all the points. But if a portion of the undulation be intercepted
by the interposition of an opaque body, then the intensity of each
part will vary according to the distance from the margin of the
shadow, and these variations will be particularly sensible in the
neighbourhood of the tangent rays.
[Illustration]
Let C be the luminous point, AG the screen, and AME the wave, arrived
at A, and partly intercepted by the opaque body. We may suppose it
to be divided into an infinite number of small arcs, A_m′_, _m′__m_,
_m_M, M_n″_, _n″__n′_, _n′__n_, and so forth. In order to find its
intensity at the point P, belonging to any subsequent situation of
the undulation, BPD, we must find the result of all the elementary
agitations which each of these portions of the primitive undulation
would produce there if they acted separately.
The impulse, which has been given to every part of the [p436]
primitive undulation, being perpendicular to its surface, the
motions of the particles of ether in this direction must be more
considerable than in any other; and the rays depending on these
motions, if separately considered, would be so much the weaker as
they deviated the more from this direction.
The investigation of the law by which their intensity would be
governed, according to their direction, as derived from any
separate centre of agitation, would certainly be of very difficult
investigation: but happily we are not obliged to determine this law,
for it is easy to see that when the inclination to the perpendicular
is considerable, the effects of the different rays must very nearly
destroy each other: so that these rays, which sensibly affect the
quantity of light received at each point P, may safely be regarded as
being equal in intensity.
When the centre of agitation has undergone a condensation, the
expansive force tends to urge the molecules in every direction; and
if they do not perform a retrograde motion, it is only because their
initial velocities forwards destroy those which the expansion of the
condensed fluid would otherwise generate backwards: but it does not
follow from this that the agitation can only be propagated in the
direction of the initial velocities; for the expansive force in a
perpendicular direction, for example, will combine with the primitive
impulse without any diminution of its effects. It is obvious that
the intensity of the undulation thus produced may vary much at the
different points of its circumference, not only from the nature of
the initial impulse, but also because the condensations are not
subject to the same law on every side of the centre of the agitated
part[?]. But the variations of the intensity of the derivative
undulation must necessarily be subjected to a law of continuity, and
may consequently be considered as insensible in a very small angular
interval, especially in the neighbourhood of the perpendicular to the
surface of the primitive undulation; for the initial velocities of
the molecules, referred to any given direction, being proportional
to the cosines of the angles made by that direction with the
perpendicular, these results vary much [p437] more slowly than the
angles themselves, while they remain inconsiderable.
If, in fact, we consider rays sensibly inclined to each other,
such as EP, FP, IP, meeting in the point P, which we may suppose
at the distance of a great number of breadths from the undulation
EA: and if we take two arcs, EF and FI, of such a length that the
differences EP−FP and FP−IP may be equal to half an undulation: on
account of the marked obliquity of the rays, and of the smallness of
a semiundulation, in proportion to their length, these two arcs will
be almost equal, and the rays which come from them to the point P
will be nearly parallel; so that on account of the difference of a
semiundulation between the corresponding rays of the two arcs, their
effects will mutually destroy each other.
We may therefore suppose all the rays sent by the different parts
of the undulation at AE, to the point P, to be of equal intensity,
since the only rays, with respect to which this hypothesis would be
incorrect, are such as have no sensible influence on the quantity of
light which it receives. For the same reason, in order to simplify
the calculation of the result of all these elementary undulations,
we may consider their constituent motions as performed in the
same direction, the angles which they form with each other being
inconsiderable. The problem is thus reduced to that which has been
solved in the Memoir on Diffraction, already quoted: _To find the
result of any number of systems of parallel undulations of light, of
the same frequency, when their intensities and relative situations
are given_.—The intensities are here proportional to the length of
the small illuminating arcs, and the relative situations are given
from the differences of the paths described.
We have considered, correctly speaking, only the section of the
undulation made by a plane perpendicular to the margin of the screen
represented by A. We may now take into account the whole extent
of the undulation, and suppose it to be divided, by equidistant
meridians perpendicular to the plane of the figure, into infinitely
thin wedges or strata; and we may apply to all of these the reasoning
which has [p438] been employed for one section, and thus demonstrate
that the rays which have a marked obliquity must destroy each other.
These strata, in the case here considered, being all parallel to the
edge of the screen, and infinitely extended, while the undulation
is intercepted but on one side; the intensity of the result of all
the impressions, which they transmit to P, will be the same for each
of them: for the rays emanating from them must be considered as of
equal intensity, at least for the very small extent of the generating
undulation, which has a sensible influence on the light received at
P. Besides, each elementary result will evidently be retarded by the
same quantity, with respect to the ray derived from the point of the
stratum nearest to P, that is to say, to the point in which it cuts
the plane of the figure: consequently the intervals between these
elementary results will be equal to the differences of the paths
described by the rays AP, _m′_P, _m_P, and so forth, which are in
the plane of the figure, and their intensities will be proportional
to the arcs A_m′_, _m′_, _m_, _m_M, and so forth. We may therefore
consider the intensity of the general result as determined by the
calculation already mentioned, as belonging to the section of the
undulation made by a plane perpendicular to the margin of the screen.
While the outline of the screen remains rectilinear, it is
sufficient, in order to determine the situations of the dark and
light stripes, and their relative intensities, to consider the
section of the undulation made by a plane perpendicular to that
outline: but when it is curved, or composed of lines meeting at any
angles, it becomes necessary to obtain the integral effect for two
directions at right angles to each other, or for a circle surrounding
the point considered. This last method is the most simple in some
particular cases, as when we have to calculate, for example, the
intensity of the light in the projection of the centre of a circular
screen or opening: [a simplification which, though sufficiently
obvious, had perhaps not occurred to Mr. FRESNEL, until it was
pointed out to him by the Translator of this paper.]
It will now be easy to form a distinct idea of the method [p439]
which must be followed, in order to calculate the situation and
the intensity of the dark and bright stripes, in the different
circumstances under which it is proposed to compare the theory with
experiment. When the screen is infinitely extended on one side, or
is broad enough to allow us to neglect the rays which pass beyond
it, we are to determine, for any point P at the distance of the
place at which the fringes are to be observed, the result of all
the elementary undulations coming from the part AMF only of the
incident wave; and comparing the intensities at different collateral
points, P, P′, P″, we are to find the situation of the darkest and
the brightest points. In this manner we find, for a screen closed
on one side, 1st, that the intensity of the light decreases rapidly
within the [shadow] beginning from the tangent CAB, and _so much the
more rapidly as the undulation is smaller_; and this in a continuous
manner, without any alternations of maxima and minima; 2ndly, that
out of the shadow, the intensity of the light, after augmenting
considerably to a certain point, which may be called a maximum of
the first order, decreases to another point, which is the minimum
of the first order: that it increases again to a second maximum, to
which succeeds a second minimum, and so forth; 3rdly, that none of
these minimums completely vanish, as in the case of fringes produced
by the concourse of two luminous pencils of equal intensity, and
that the difference between the maxima and minima diminishes in
proportion as we go further from the shadow; whence we may understand
why the fringes which surround shadows in a homogeneous light, are
less marked and less numerous, than those which are obtained by
a combination of two mirrors, and those in white light much less
brilliant; 4thly, that the intervals been the maxima and minima are
unequal, and diminish, as we depart from the shadow, in proportions
which remain unaltered, whatever may be the distance from the screen
at which we measure them; and 5thly, that the same maxima and minima,
calculated for different distances from the screen, are situated in
hyperbolas of a sensible curvature, of which the foci are the edge
of the screen, and the luminous point. All these consequences of the
theory are precisely confirmed by experiment. [p440]
The general formula gives the position of the maxima and minima for
any distances whatever of the luminous point from the screen, and
from the screen to the micrometer, when the length of the undulation
of the light employed is known. In order to submit the theory to a
decisive test, instead of determining the length of the undulation
by measures of the external fringes, and then employing it in
calculations of the same kind, I deduced it from an experiment on
diffraction of a very different kind; and after having first verified
it by the fringes obtained from two mirrors, of which it represented
the breadth within a hundredth part of the truth, I introduced it
into the formula which I afterwards compared with 125 measurements of
exterior fringes, made under very different circumstances; for the
distance of the radiant point from the screen was varied from four
inches to six or seven yards, and the distance between the screen
and the micrometer was varied from 1/13th of an inch to more than
four yards: and the results of all these comparisons were perfectly
satisfactory, as maybe seen in the comparative table published in the
XIth volume of the Annales de Chimie et de Physique, p. 339, 343.
When the screen, instead of extending infinitely on one side, is
narrow enough to admit some light on that side, not too much weakened
by the rapid decrease of intensity produced by obliquity, we must
take into the calculation the light on both sides, and find, for
each point of the shadow, the general result of all the elementary
undulations derived from the points on the right and left. We thus
demonstrate that the interior parts of the shadow must be divided
by a series of dark and bright stripes, nearly equal in breadth,
of which the situations differ very little from those which would
be deduced from the approximative formula which has already been
given for the same purpose, when they are still separated from the
borders of the shadow by an interval of several of their breadths.
But when the opaque body is narrow enough, and the micrometer far
enough removed for the observed stripes to be very near the exterior
stripes, then the results of this more exact calculation, as well
as those of experiment, show that the approximation is no longer
accurate. The [p441] calculation determines also, with remarkable
precision, the singular alterations which the exterior fringes often
undergo, when the other series extends beyond the shadow, and mixes
its effects with those of the exterior.
I have also verified the theory by examining the fringes derived
from a narrow slit of indefinite length; and determining, for the
different points enlightened by the luminous pencil, the result of
all the elementary undulations derived from the part of the primitive
wave comprehended in the breadth of the slit; and I have found a
satisfactory agreement between the calculation and the observations,
even when the fringes thus obtained afforded the most capricious and
apparently irregular appearances.
In this mode of considering the problems relating to diffraction, we
have not taken into the calculation the greater or less thickness of
the edges of the screen, but merely the extent of the primitive wave
which is capable of sending elementary undulations to the points for
which we are to find the intensity of illumination; and the opaque
substance has no other effect than simply to intercept a part of the
wave: for this reason the result is necessarily independent of the
nature of the body, of its mass, and of the thickness of its edges.
Nevertheless, if the surface of the edges were very extensive, it
would be impossible to consider the portion of the wave as quitting
the slit without having received some previous modification, and it
would be necessary to take into the calculation the small fringes
derived from the effect of the remoter parts of the slit. But
while the thickness is moderate, or the edges rounded off into a
well marked curve, the small fringes derived from this cause may
be neglected, and the emerging wave may be considered as of equal
intensity throughout, at the moment of its quitting the screen,
especially if the intensity of the light is to be calculated for a
pretty considerable distance from the screen. We must not, indeed,
forget, that according to the reasoning which has been employed,
the formulas for diffraction are only sufficiently exact when this
distance is very considerable, in comparison with the breadth of an
undulation, since it is in this case only that we can neglect the
rays that are decidedly oblique, and [p442] can suppose all those,
which are essentially concerned in the effect, to be nearly of equal
intensity. It is not, however, surprising that the same formulas will
give the position of the fringes with sufficient accuracy at small
distances from the screen, when its edges are thin, since, the mean
breadth of an undulation being but about one fifty thousandth of an
inch, a tenth of an inch becomes comparatively a very considerable
distance.
These are the three principal kinds of phenomena presented to us by
diffraction, when the edges of the screen, or of the opening made in
it, are sufficiently extensive to afford fringes independent of any
effect from their terminations: and in such cases it is sufficient
to make the integral calculation for the plane perpendicular to
the edges of the screen only, in order to determine the position
of the dark and bright stripes, and their comparative intensities.
But when the screen or the opening are of small dimensions in every
direction, it becomes necessary to extend the integration to the
effects produced in two perpendicular planes: and the results of the
calculation agree perfectly with observation, as will appear from two
curious instances.
When the screen is circular, the calculation leads to this singular
result, that the centre of the shadow projected by it must be as
much enlightened as if the screen were not in existence. It was Mr.
POISSON that first pointed out this consequence of my formulas,
which I did not at first observe, though it is immediately deducible
from the theory by very simple geometrical considerations. Mr. ARAGO
made the experiment with the shadow of a screen 1/13th of an inch
in diameter, perfectly round, and fixed on a plate of glass. The
result confirmed the fact which had been announced by the theory.
It is only the centre itself that possesses this property, and the
same brightness is only extended to a sensible distance from this
mathematical point when the screen is of very small diameter, and
when its shadow is observed at a great distance: for the wider that
the screen becomes, the more the little bright circle is contracted;
and when the screen is four tenths of an inch in diameter, we only
see a single point of light, at the distance of a yard, even with a
powerful magnifier. It must be observed, that if the screen [p443]
were too large, the reasoning, from which the formulas have been
deduced, would no longer be rigorously applicable to the rays
inflected into the shadow, because of their too great obliquity,
which would render it impossible to consider their effects as equal
in intensity to those of the direct rays.
When we calculate, by the same formulas, the intensity of the light
in the centre of the projection of a small circular aperture, made
in a large screen, we find that this centre will exhibit alternately
a bright and a dark appearance, according to the distance at which
the shadow is viewed; and that in homogeneous light this darkness
must be perfect. This new inference from the general formulas may be
deduced from the theory by very simple geometrical considerations.
Thus we find that the values of the successive distances, at
which the centre of the shadow becomes completly dark, are _b_ =
_a__r_^2/(2_a__d_−_r_^2), _b_ = _a__r_^2/(4_a__d_−_r_^2), _b_ =
_a__r_^2/(8_a__d_−_r_^2); and so forth; _r_ being the semidiameter
of the aperture, _a_ and _b_ its respective distances from the
luminous point and from the micrometer, and _d_ the length of the
undulation of the light employed. Now, if we place the micrometer at
the distances indicated by these formulas, we observe, in fact, that
the centre of the projection of the opening is so completely deprived
of light, that it appears like a spot of ink in the middle of the
illuminated part, at least with respect to the minimums of the first
three orders, as indicated by the formulas here inserted: those of
the subsequent orders, which are nearer to the screen, exhibiting
no longer the same degree of darkness, on account of the want of
homogeneity of the light employed.
There is still a multitude of other phenomena of diffraction, such
as those of multiplied and coloured images, reflected by striated
surfaces, as seen through a texture of fine fibres, as well as the
coloured rings, produced by an irregular collection of such fibres,
or of light powders, consisting of particles nearly equal, placed
between the eye of the spectator and a luminous object; all of which
may be explained and rigorously computed by means of the theory which
has been laid down. It would, however, occupy too much of our time
to describe them here, and to [p444] show how exactly they concur
in confirming the theory; which indeed appears to be abundantly
demonstrated by the numerous and diversified facts which have been
already adduced in support of it. It will be sufficient to conclude
this extract of the Memoir on Diffraction with a detailed description
of an important experiment of Mr. ARAGO, which furnishes us with a
method of determining the slightest differences of the refractive
powers of bodies, with a degree of accuracy almost unlimited.
We have seen that the fringes, produced by two very narrow slits, are
always placed symmetrically with regard to a plane passing through
the luminous point and the middle of the interval between the slits,
as long as the two pencils of light which interfere have passed
through the same medium, for instance, the air, as happens in the
ordinary arrangement of the apparatus. But the result is different
when one of the pencils continues to pass through the air, and the
other has to be transmitted by a more refractive body, a thin plate
of mica, for example, or a piece of glass blown very thin: the
fringes are then displaced, and carried towards the side on which
the transparent substance is placed: and if its thickness becomes
at all considerable, they are removed out of the enlightened space,
and disappear altogether. This important experiment, which was first
made by Mr. Arago, may also be performed with the apparatus of the
two mirrors, if the plate be placed in the way of one of the pencils,
either before or after its reflection.
Let us now see what inference may be drawn from this remarkable fact,
by the assistance of the principle of interferences. The light stripe
in the middle is always derived, as we have already seen, from the
simultaneous arrival of rays which have issued at the same moment
from the luminous point; consequently, in the common circumstances
of the experiment, they must have described paths exactly equal, in
order to arrive in the same time at the place of meeting: but it
is obvious that if they pass through mediums in which light is not
propagated with the same velocity, that pencil, which has travelled
the more slowly, will arrive at the given point later than the other,
and the point will [p445] therefore no longer be in the bright
stripe. The stripe must therefore necessarily change its place
towards the pencil which travels the more slowly, in order that
the shortness of its path may compensate for the delay during its
transmission through the solid: and the converse of the proposition
enables us to conclude, that where the stripes are displaced, the
pencil towards which they move has been retarded in its passage. The
natural inference, therefore, “from Mr. ARAGO’s experiment,” is, that
light is propagated more rapidly in the air than in mica or glass,
and generally in all bodies more refractive than the air; a result
directly opposite to the Newtonian theory of refraction, which,
supposes the particles of light to be strongly attracted by dense
substances, which would cause the velocity of light to be greater in
these bodies than in rarer mediums.
This experiment furnishes a method of comparing the velocity of the
propagation of light in different mediums, [or, in other words,
the refractive density, which is always supposed in this theory,
to be reciprocally proportional to it.] If, in fact, we measure
very accurately, by means of a spherometer, the thickness of the
thin plate of glass which has been placed in the way of one of
the luminous pencils, and if the displacement of the fringes has
been measured by the micrometer; since we know that, before the
interposition of the glass, the paths described were equal for the
middle of the central stripe, we may calculate how much difference
is occasioned by the change of position, and this difference will
give the retardation in the plate of glass, of which the thickness
is known: so that, by adding this thickness to the difference
calculated, we shall find the little path which the other pencil has
described in the air, while the former was transmitted by the plate
of glass; and this path, compared with the thickness of the plate of
glass, will give the proportion of the velocity of the light in the
air, to its velocity within the glass.
We may also consider this problem in another point of view, with
which it is convenient to make ourselves familiar. The duration of
each undulation, as we have seen, does not depend on the greater or
less velocity with which the [p446] agitation is propagated along
the fluid, but merely on the duration of the previous oscillation
which gave it birth; consequently, when the luminous waves pass
from one medium into another, in which they are propagated more
slowly, each undulation is performed in the same interval of time as
before, and the greater density of the medium has no other effect
than that of diminishing the length of the undulation, in the same
proportion as the velocity of light is diminished: for the length
of the undulation is equal to the space that the first agitation
describes during the time of a complete oscillation. We may therefore
calculate the relative velocities of light in different mediums, by
comparing the length of the undulations of the same kind of light in
those mediums. Now, the middle of the central stripe is formed by the
reunion of such rays of the two pencils as have performed the same
number of undulations, in their way from the luminous point, whatever
may be the nature of the mediums transmitting the light. If then the
central stripe is brought towards the side of the pencil which has
passed through the glass, it is because the undulations of light are
shorter within the glass than in the air; and it is necessary, in
consequence, that the path described on this side should be shorter
than the other, in order that the number of undulations may remain
the same. Let us suppose, then, that the central stripe has been
displaced to the extent of twenty breadths of fringes, for example,
or of twenty times the interval between the middle points of two
consecutive dark stripes; we must necessarily conclude that the
interposition of the plate of glass has retarded the progress of
the pencil passing through it to the extent of twenty undulations;
or that it has performed within the plate twenty undulations more
than the same pencil would have performed in an equal thickness of
air, since each breadth of a fringe answers to the difference of a
single undulation. If then we know the thickness of the plate, and
the length of an undulation of the light employed, which is easily
deduced from the measurement of the fringes, by the formula that has
been given, we can calculate the number of undulations comprehended
in the same thickness of air, and by adding twenty to the number, we
shall have that of the [p447] undulations performed in the thickness
of the glass; and the proportion of these two numbers will be that of
the velocities of light in the different mediums. Now this proportion
is found by experiment the same with that of the sines of incidence
and of refraction between air and glass; which agrees with the theory
of the refraction of undulations, as will be seen hereafter.
The same experiment may be employed, on the other hand, for
determining with extreme precision the thickness of a thin plate of a
substance of known refractive density; placing it in the way of one
of the two pencils of light, and measuring the displacement of the
fringes which it occasions.
This method of determining refractive densities is however liable to
some difficulties, when we wish to apply it to a body much more dense
than air, such as water, or glass, for example; since it is necessary
to employ a very thin plate only, in order that the fringes may not
be too much displaced for observation; and then it becomes difficult
to measure the thickness of such a plate with sufficient accuracy.
We may, indeed, place in the way of the other pencil a thick plate
of a transparent substance, of which the refractive density has been
ascertained by the ordinary methods, and we can then employ as thick
a plate of the new substance. But then it becomes simpler to measure
its refractive density by the common method: [unless we choose to
immerse the whole apparatus in a fluid very nearly approaching
to it in refractive density, which may sometimes be done without
inconvenience. TR.]
The case, in which Mr. Arago’s experiment has a decided advantage
over the direct method, is when we desire to determine very slight
differences of velocity in mediums of nearly equal refractive
density: for by lengthening the passage of the light in the two
mediums of which we wish to compare the refractive density, we can
increase the accuracy of the results almost without limit. In order
to form an idea of the extreme precision that may be attained by
these measurements, it is sufficient to observe that the length of
the yellow undulations in air being about .000021 E.I., there are two
millions of them in the length of about 42 inches. Now [p448] it is
very easy to observe the difference of one fifth of a fringe, which
corresponds to a retardation of one fifth of an undulation in one of
the pencils, that is, the ten millionth part of the whole length of
42 inches; we might therefore, by introducing any gas or vapour into
a tube of this length, terminated by two plane glasses, estimate very
accurately the variation of its refractive power.
I take the length of an undulation of the yellow rays, which are
the most brilliant of the spectrum, and of which the dark and light
stripes consequently coincide with the darkest and brightest stripes
of the fringes produced by white light, which is commonly employed
in these experiments, both because of its greater brightness, and
because of the more marked character which it gives to the central
stripe, so as to prevent any other from being mistaken for it.
It was an apparatus of this kind that Mr. ARAGO and myself employed
for measuring the difference of the refractive powers of dry air, and
of air saturated with moisture at 80° F., which is so small, that it
would escape every other method of observation, because the greater
refractive power of aqueous vapour is almost exactly compensated
by the less specific gravity of moist air. But, in the generality
of cases, the slightest mixture of one vapour or gas with another
produces a considerable displacement in the fringes: and if we had
a series of experiments of this kind, made with care, the apparatus
might become a valuable instrument of chemical analysis.
[To be continued.]
iii. _Remarks on the Action of_ CORPUSCULAR FORCES. _In a Letter to_
Mr. POISSON.
My dear Sir,
I am very glad to see that you have been applying your analytical
powers to the investigation of the acustical effects of corpuscular
forces, and that, among many more refined determinations, you, have
confirmed several of the results relating to sounding bodies, which
were published twenty years ago in my Lectures on Natural Philosophy:
though they were generally such as might have been derived from
the calculations of Bernoulli and Euler; which I attempted in some
[p449] measure to simplify by the introduction of the element which
I called the _Modulus of Elasticity_ of each substance. You have
very properly observed that it is often difficult to represent the
combination of these corpuscular forces by an integral, since in many
practical cases the integral must vanish, where it would naturally be
applied to the phenomena: and, from similar considerations, I trust
you will be prepared to admit the objections that I made long ago,
to the reasoning of your great predecessor, Mr. Laplace, to whose
station in the mathematical world you appear so eminently qualified
to succeed.
The equation, which may be called final, in Mr. Laplace’s Supplement
to the Xth Book, p. 47, is _Q_ cos. (ω−θ) = (2ς−ς′) _K_ sin. θ. Now
this, in my opinion, is a perfect _reductio ad absurdum_: for _Q_
must _always_ be _incomparably_ less than _K_; the attraction of
the particles lying between a cylinder and its tangent plane being
_always_ infinitely less than that of the particles in an angular or
prismatic edge: or if this were denied in general, it would obviously
become true when the cylinder itself becomes a plane, and _Q_
vanishes altogether; which will always be the state of the problem,
when the surface of the solid is so inclined to the horizon, that the
surface of the fluid may remain horizontal, the appropriate angle of
contact being unaltered in these circumstances, as it is easy to show
by making the experiment with mercury.
I entreat you to consider this objection with patient attention, and
to tell me if you can find any arguments to supersede it. I would
also presume to ask your opinion of my own method of deducing the
force of capillarity from the elementary attractions and repulsions
of bodies, at the end of my Illustrations of the Celestial Mechanics,
Art. 382; Appendix A, p. 329 to 337. The volume is in the Library
of the Academy; or I should have taken the liberty of sending you a
copy, as an inadequate return for so many valuable communications
with which you have had the kindness to favour me.
Believe me always, dear Sir,
Very truly yours,
* * * *
_London_, 18 _Nov._ 1827.
[p450]
iv. _Calculations of_ LUNAR PHENOMENA. _By_ THOMAS HENDERSON, Esq.
----------------------------------------------------------------------+
Principal LUNAR OCCULTATIONS of the Fixed Stars in the |
Months of January, February, March, and April, 1828; calculated |
for the Royal Observatory at Greenwich. |
---------+---------------+------+--------------+-------------+--------+
| | | Immersion and| Apparent |Point of|
Date. | Names of |Magni-| Emersion. |Difference of| Moon’s |
| Stars. |tude. | Mean Time. |Declination. | Limb. |
---------+---------------+------+--------------+-------------+--------+
| | | H. M. S. | ′ * ″ | ° |
Jan. 4|κ Cancri | 5.6 |Imm. 10 51 43 | 13 18 S. | 172 R. |
| | |Em. 11 44 48 | 7 19 S. | 91 R. |
31|α^1 Cancri | 6 |Imm. 11 14 52 | 7 45 S. | 134 L. |
| | |Em. 12 35 56 | 2 19 N. | 88 R. |
" |κ Cancri | 5.6 |Imm. 18 38 0 | 0 58 N. | 47 L. |
| | |Em. Under | Horizon. | |
Feb. 7|α^2 Libræ | 3 |Imm. 20 29 54 | 1 35 S. | 69 L. |
| | |Em. 21 37 54 | 4 33 N. | 107 R. |
22|δ^3 Tauri | 5 |Imm. 7 0 9 | 3 47 S. | 90 L. |
| | |Em. 8 16 39 | 6 34 S. | 146 R. |
28|ω Leonis | 6.7 |Imm. 11 24 25 | 14 57 S. | 165 L. |
| | |Em. 12 3 15 | 9 17 S. | 145 R. |
March 10|ρ^1 Sagittarii | 5 |Imm. 16 14 54 | 4 24 N. | 105 L. |
| | |Em. 17 20 39 | 1 25 N. | 62 R. |
23|u Geminorum | 5.6 |Imm. 8 4 36 | 2 48 N. | 55 L. |
| | |Em. 9 18 11 | 7 46 N. | 94 R. |
24|k Geminorum | 5 |Imm. 9 12 5 | 3 53 S. | 78 L. |
| | |Em. 10 28 34 | 3 55 N. | 111 R. |
26|κ Cancri | 5.6 |Imm. 7 41 25 | 7 6 S. | 132 L. |
| | |Em. 9 3 38 | 3 14 N. | 83 R. |
April 2|ν^1 Libræ | 6 |Imm. 14 7 43 | 12 43 N. | 38 L. |
| | |Em. 14 34 56 | 15 49 N. | 10 R. |
|ν^2 Libræ | 6.7 |Imm. 13 58 36 | 2 1 S. | 99 L. |
| | |Em. 15 13 58 | 6 19 N. | 76 R. |
29|α^1 Libræ | 6 |Imm. 16 15 38 | 14 48 S. | 126 L. |
| | |Em. 16 48 16 | 11 55 S. | 174 R. |
|α^2 Libræ | 3 |Imm. 16 33 5 | 15 54 S. | 145 L. |
| | |Em. 16 43 5 | 15 3 S. | 162 L. |
---------+---------------+------+--------------+-------------+--------+
The fifth column shows the apparent difference of declination
between the Star and Moon’s centre at the immersion and emersion;
the letters N and S denoting the Star to be north or south from the
Moon. The sixth or last column shows the point of the Moon’s limb
where the immersion and emersion take place, reckoning from the
vertex or highest point; the letters L and R signifying to the left
hand or right hand of the observer.
An error of 11 seconds in the computed difference of declination
between the Moon and Star, will be sufficient to convert the
expected Occultation of α^2 Libræ, on 29th April, into an Appulse;
and a less error will considerably affect the times and places of
immersion and emersion.
[To be continued.]
+----------------------------------------------------------------------+
[p451]
+----------------------------------------------------------------------+
ELEMENTS for computing the ECLIPSES of the SUN and OCCULTATIONS of
the PLANETS by the Moon, in the Year 1828.
Conjunction in Diff. Relat Relative ☉ or Pla ☉ or Pla
A. R. Apparent Dec. ive Orb. Ang. net’s A. net’s N.
Time. H. M. R. at ☌ P. D. at ☌
☽ D. H. M. S. ′☽ ″ ′ ″ ° ′ H. M. S. ° ′ ″
♃ Jan. 11 10 47 11 21 1 S. 34 6 S. 76 58 E. 14 35 47 104 2 30
♂ Jan. 11 16 40 36 4 29 N. 33 14 S. 78 4 14 49 29 105 12 34
♃ Feb. 7 22 17 54 5 44 N. 33 26 S. 77 35 14 46 40 104 48 7
♃ Mar. 6 4 48 7 16 46 N. 33 29 S. 77 47 14 49 7 104 53 57
♃ April 2 8 6 49 9 6 N. 34 12 S. 77 26 14 42 44 104 21 7
☉ April 13 21 23 53 8 50 N. 31 23 N. 74 7 1 30 20 80 32 14
♃ April 29 10 49 53 9 3 S. 34 50 S. 76 40 14 30 21 103 22 5
☿ May 12 8 58 41 7 44 N. 27 31 N. 78 28 2 30 50 76 35 6
♃ May 26 14 58 46 20 58 S. 34 38 S. 75 54 14 17 53 102 23 57
♃ June 22 21 27 33 14 27 S. 33 40 S. 75 26 14 11 5 101 55 51
♀ July 13 12 0 30 68 43 S. 30 15 S. 76 50 8 55 0 76 17 27
♃ July 20 6 18 33 10 12 N. 32 33 S. 75 28 14 12 35 102 11 28
♃ Aug. 16 17 18 6 44 49 N. 31 50 S. 75 59 14 22 10 103 7 21
♀ Sept. 5 3 7 12 4 10 S. 28 8 S. 78 3 8 13 4 75 7 21
☉ Oct. 8 12 23 35 6 39 S. 29 6 S. 73 2 12 57 44 96 10 27
♀ Dec. 3 13 30 46 39 10 S. 29 39 S. 75 23 14 3 58 100 19 38
Conjunction in A. Nearest Time of { ☉ or Planet’s }
R. Apparent Time. Approach. nearest Horary Motion Semi- Hor.
Approach, in A. in N. diam- Par.
Apparent R. in P. D. eter
Time. Time.
☽ D. H. M. S. ′ ″ D. H. M. S. SEC. ″ ″ ″
♃ Jan. 11 10 47 11 20 28 11 10 38 51 + 1·3 + 6 17 2
♂ Jan. 11 16 40 36 4 23 11 16 42 16 + 5·9 + 27 3 5
♃ Feb. 7 22 17 54 5 36 7 22 20 7 + 0·6 + 2 18 2
♃ Mar. 6 4 48 7 16 23 6 4 54 29 − 0·2 − 1 20 2
♃ April 2 8 6 49 8 53 2 8 10 18 − 0·9 − 4 21 2
☉ April 13 21 23 53 8 30 13 21 19 16 + 9·2 − 54 958 9
♃ April 29 10 49 53 8 48 29 10 46 17 − 1·2 − 6 22 2
☿ May 12 8 58 41 7 35 12 8 55 19 +19·8 −119 3 7
♃ May 26 14 58 46 20 20 26 14 49 55 − 0·9 − 4 21 2
♃ June 22 21 27 33 13 59 22 21 21 5 − 0·3 − 1 20 2
♀ July 13 12 0 30 66 55 13 11 29 28 − 3·4 + 22 26 27
♃ July 20 6 18 33 9 53 20 6 23 16 + 0·5 + 3 18 2
♃ Aug. 16 17 18 6 43 29 16 17 38 31 + 1·2 + 6 17 2
♀ Sept. 5 3 7 12 4 5 5 3 5 22 + 5·8 − 1 18 19
☉ Oct. 8 12 23 35 6 21 8 12 19 35 + 9·2 + 57 963 9
♀ Dec. 3 13 30 46 37 54 3 13 10 46 +11·5 + 61 7 8
The places of the Sun and Moon have been taken from the Nautical
Almanac, those of Mercury from Lindenau’s Tables, and those of the
other Planets from Schumacher’s Ephemeris.——The sign + denotes the
motion in A. R. to be direct; the sign −, retrograde. The sign +
denotes the motion in N. P. D. to be towards the South; the sign −
towards the North.——None of the preceding Conjunctions will prove
to be an Eclipse or Occultation visible at Greenwich.
+----------------------------------------------------------------------+
[p452]
+-----------------------------------------+
Apparent Distance of Jupiter’s Satellites
from Jupiter’s Centre, at his Conjunctions
in A. R. with the Moon.
+------------+----------+-----------------+
Date. Satellite. Distance.
+------------+----------+-----------------+
1828. ′ ″
+------------+----------+-----------------+
January 11 I. 1 14 East
II. 0 51 ----
III. 4 16 West
IV. 2 21 ----
February 7 I. 1 6 West
II. 2 40 East
III. 2 16 West
IV. 4 27 ----
March 6 I. 1 51 East
II. 2 24 West
III. 3 14 East
IV. 8 44 ----
April 2 I. 1 44 West
II. 0 15 ----[A]
III. 4 58 East
IV. 7 30 West
29 I. 0 14 West[B]
II. 2 51 East
III. 0 32 West
IV. 1 6 East
May 26 I. 1 44 East
II. 3 8 West
III. 5 15 ----
IV. 6 38 East
June 22 I. 1 59 West
II. 0 4 East[C]
III. 3 10 West
IV. 8 56 ----
July 20 I. 1 51 East
II. 2 50 ----
III. 1 55 ----
IV. 4 51 ----
August 16 I. 1 43 West
II. 1 12 ----
III. 4 21 East
IV. 1 53 ----
+------------+----------+-----------------+
A: On Jupiter’s disk. B: Eclipsed.
C: On Jupiters disk.
These Configurations have been computed
from De Lambre’s Tables.
+-----------------------------------------+
[p453]
MISCELLANEOUS INTELLIGENCE.
I. MECHANICAL SCIENCE.
1. _On the Adhesion of Screws_.—The following results, respecting the
force necessary to draw iron screws out of given depths of wood, are
by Mr. Bevan, and should be placed by the side of those he has given
with regard to nails[128].
“The screws I used were about two inches in length, 0.22 diameter at
the exterior of the threads, 0.15 diameter at the bottom, the depth
of the worm or thread being 0.035, and the number of threads in one
inch = 12. They were passed through pieces of wood exactly half an
inch in thickness, and drawn out by the weights specified in the
following table:
Dry beech 460 pounds
Do. Do. 790
Dry sound ash 790
Dry oak 760
Dry mahogany 770
Dry elm 655
Dry sycamore 830
“The weights were supported about two minutes before the screws were
extracted.
“I have also found the force required to draw similar screws out of
deal and the softer woods about half the above.
“From which we may infer as a rule to estimate the _full_ force
of adhesion, in hard wood . . . 200.000 _d_ δ _t_ = _f_,
and in soft wood . . . 100.000 _d_ δ _t_ = _f_,
_d_ being the diameter of the screw; δ the depth of the worm
or thread; and _t_ the thickness of the wood into which it is
forced;—all in inches; _f_ being the force in pounds to extract the
same.” We may, from the above experiments, observe the approximation
to perfection in the art of screw making; for had the screw been
greater in diameter, there would have been a waste of material, or
had it been less, it would not have been sufficiently strong, which
may be proved as follows: the cohesion of wrought iron has been
found, from a number of experiments, to be about 43000 lbs. per
cylindrical inch; and as the smallest diameter of screw used in my
experiment was 0.15, it would have been torn asunder by a force of
about 968 lbs.; or if the hard wood had been about 5/8 of an inch
thick into which it had been screwed, the screw would have been
broken instead of forcing its passage out of the wood.—_Phil. Mag. N.
S._ ii. 291.
FOOTNOTE:
[128] See page 360, vol. xvii. of the former series of this Journal.
2. _Improvement in Steam-engines_.—According to the valuable records
kept of the duty of the steam-engines at the mines in Cornwall,
a most important improvement has been effected in two [p454]
instances, of engines erected by Captain Samuel Grose; dependent
entirely upon attention to the smaller details of the machines. The
best engines, heretofore, had not done more than raise forty millions
of pounds of water one foot high, by each bushel of coals consumed,
except indeed upon short occasions. In one of the cases in question,
an engine at Wheal Hope, of sixty-inch cylinder, working single as
usual, the duty rose to fifty, fifty-four, and fifty-five millions of
pounds; and in the other, an engine of eighty-inch cylinder, at Wheal
Towan, the duty rose in
April 61,877,545
May 60,632,179
June 61,762,210
July 62,220,820
August 61,764,166
thus exceeding by nearly fifty per cent. what had been effected
before that time.
3. _Improved Clock_.—Among the articles displayed at the first
National Exhibition of the Objects of Arts and Industry, at
Neufchatel, Switzerland, last year, was a clock made by F. Houriet,
of Locle; in which steel was used only in the main springs and in the
axes of the moveable parts; all the other parts were in brass, gold
alloy, and white gold. The number of pieces in gold, gold and silver,
gold and platina, is sixty-two: all the pivots turn on jewels, and
the functions of the free escapements are effected also by means of
pallets in precious stones. It had been supposed that the escapements
and the spiral spring not being of steel, inconvenience would result
from the smaller degree of elasticity, but numerous trials with
favourable results have removed the objection; and it appears that
gold, hardened either by hammering or other means, is more elastic
than hardened and untempered steel. The clock had gone for six days,
exposed to the contact of a magnet competent to lift twenty-five or
thirty pounds, without suffering any derangement.—_Rév. Ency._
4. _Method of dividing Glass by Friction_.—The following method is
described by Dr. Hare: “Some years ago Mr. Lukin showed me that a
small phial or tube might be separated into two parts, if subjected
to cold water after being heated by the friction of a cord made to
circulate about it, by two persons alternately pulling in opposite
directions. I was subsequently enabled to employ this process in
dividing large vessels of four or five inches in diameter, and
likewise to render it in every case more easy and certain by means
of a piece of plank forked like a boot-jack, and also having a
kerf cut by a saw, parallel to and nearly equidistant from the
principal surfaces of the plank, and at right angles to the incisions
productive of the fork.
“By means of the fork, the glass is easily held steadily by the
hand of one operator; by means of the kerf, the string, while
[p455] circulating about the glass, is confined to the part where
the separation is desired. As soon as the cord smokes, the glass is
plunged in water, or if too large to be easily immersed, the water
must be thrown upon it; the latter method is always preferable when,
upon immersing the body, the water can reach the inner surface.
As plunging is the most effectual method of employing the water
in the case of a tube, I usually close the end which is to be
immersed.”—_Silliman’s Journal_, xiii. 7.
5. _Use of Soapstone in diminishing Friction_.—In a letter to
Professor Silliman upon this subject, Mr. E. Bailey of Boston, says,
“I understand the Soapstone has been used for this purpose in the
extensive manufactories at Lowell, for about two years, and with
great profit and success. Besides answering the purpose to which it
is applied very much better than any other substance that can be
procured, it saves a great deal of trouble and expense. It is first
thoroughly pulverized, and then mixed with oil, tallow, lard, or
tar, whichever may be the best adapted to the use for which it is
designed. It is of course important to procure that which is free
from _grit_, and it can be purified in a good degree by mixing the
powder with oil, and decanting it after it has stood a few minutes.
The heavier particles will form a sediment to be rejected. It is used
in all kinds of machinery where it is necessary to apply any unctuous
substance to diminish friction, and it is said to be an excellent
substitute for the usual composition applied to carriage-wheels.”
Some idea of the value of soapstone thus applied, may be formed from
the following fact communicated by D. Moody, Esq., the superintendent
of the tar-works on the mill-dam near this city. Connected with
the rolling machine of that establishment, there is a horizontal
balance-wheel, weighing _fourteen tons_, which runs on a step of
five inches diameter, and makes from seventy-five to one hundred
revolutions in a minute. About one hundred tons of iron are rolled in
this machine in a month; yet the wheel has sometimes been used from
three to five weeks without inconvenience, before the soapstone has
been renewed. The superintendent thinks, however, that it ought to be
more frequently employed.
“The use of soapstone was discovered at Lowell. It has been
said never to fail in producing the desired result when applied
to machinery which had began to be heated, even in those
cases when nothing else could be found that would answer the
purpose.”—_Silliman’s Journal_, xiii. 192.
6. _On peculiar Physical Repulsions, by_ M. Saigey.—I intend to give
in this bulletin the description of a very simple apparatus, by means
of which I have made many experiments, which have conducted me to the
following results:—
i. All bodies exert between themselves a feeble repulsive action in
ordinary circumstances. The repulsion between bismuth and [p456]
antimony and the poles of a magnetic needle, is a case of this
general law, and is not due to magnetism. Nor is it magnetism which
occasions the direction of needles formed of other substances than
iron, announced lately by M. Becquerel.
ii. A very marked attraction may be observed between a cold and a
heated body, or between two bodies of different temperature, whether
screens be interposed or not.
iii. The metallic plates in the Cabinet de Physique de Paris,
intended for the repetition of M. Arago’s experiments on magnetism by
rotation, contain more or less of iron capable of attracting a very
mobile magnetic needle. These plates, and those of M. Arago, were
made by the same person and from the same materials.
iv. I believe that, in many cases, results obtained without the
appreciable developement of magnetism or electricity, have been
attributed to these powers; and from well-proved experiments I shall
deduce new results relative to the diurnal variation of the needle,
the direction of the plumb-line and the density, temperature and
attraction of the planetary masses.—_Bull. Univ._ A. viii. 287.
7. _On the Magnetic Effects of Metals in Motion_.—M. Seebeck has
endeavoured to determine the effects of various metals in diminishing
the oscillations of a magnetic needle 2-1/8 inches in length, and
suspended by a silk fibre three lines distant from and above the
plates. The oscillations were counted from an amplitude of 45° to 10°.
116 oscillations above a plate of marble
112 layer of mercury 2 lines in thickness.
106 plate of bismuth 2 "
94 platina 0.4 "
90 antimony 2.0 "
89 lead 0.75 "
89 gold 0.2 "
71 zinc 0.5 "
68 tin 1.0 "
62 brass 2.0 "
62 copper 0.3 "
55 silver 0.3 "
6 iron 0.4 "
It is also stated that he has found, from experiments, that by
alloying such metals as are magnetic, like iron, nickel, and cobalt,
with other metals, which like antimony diminish the magnetic force,
alloys are obtained entirely neutral in their effects; thus the
alloys formed by four of antimony with one of iron, three of copper
with one of antimony, and two of copper with one of nickel, produce
no diminution of the number of oscillations, these amounting to 116
as with the plate of marble. These three alloys are, therefore, the
best for the manufacture of compasses, those of copper and nickel
being the most malleable.—_Annal. des Phy. 1826. Bull. Univ._ A.
viii. 136. [p457]
8. _Duration of the Effects of Light upon the Eye_.—M. Plateau of
Liege has endeavoured to determine the length of time during which
the impression of certain luminous rays upon the eyes remains; and
has given the following results:
Flame 0″.242
Ignited Charcoal 0″.229
White 0″.182
Blue 0″.186
Yellow 0″.173
Red 0″.184
9. _On the Measurement of the Intensity of Light, by_ M. Peclet.—A
very usual photometrical process is to interpose an opaque body
between a white screen and the two lights to be measured, and to move
the latter until the shadows produced are of equal intensity; the
intensity of the lights being then as the square of their distances
from the shadows they illuminate. Sometimes a translucent body, as
unpolished glass or oiled paper, is used in place of an opaque one,
the shades produced by transmission being observed.
In both these methods, the apparent intensity of the shadow varies
with the position of the observer. If the shadows are equal when
observed from a point perpendicular to the white screen at the middle
of the distance of the two shades, they will be no longer so on
removing from that position, and the shadow nearest to the observer
will always appear the darkest. These apparent variations are greater
as the shadows are farther apart, or with reflected shadows as the
screen is smoother, or with transmitted shadows as the interposed
obstacle is more diaphanous.
The explanation given of this fact is, that unpolished opaque bodies,
like paper, plaster, &c. never disperse the light incident upon them,
in an uniform manner, more rays passing in the direction in which
regular reflexion would take place, than in any other. Hence, when
two equal shadows are produced upon such a surface, either by two
equal lights at equal distances, or by two unequal lights at unequal
distances; the shadow nearest to the observer must necessarily appear
deeper than the other, because it is enlightened by the nearest
light, the rays from which are reflected in greatest abundance away
from the observer; and, on the contrary, the shadow further from the
observer should appear lightest, because the rays which fall on it
from the furthest light are reflected in greatest abundance towards
the side on which the observer stands. The reason, also, why the
effect is greater as the shadows are further apart is evident; and
why in every case it is reduced to nothing when the observer is in
a plane perpendicular to the screen and equidistant from the two
shadows.
From these facts and explanations it may be concluded, that, in all
photometrical measurements by reflected shadows, the screens should
have all smoothness removed from them, and the two [p458] shadows
brought as near together as possible, and even made to touch or
over-lap; or that, when this cannot be done, the observation should
be made from a point equidistant from the two shadows. As to the
shadows by transmission, the apparent variations of intensity are so
great for small changes in the position of the eye, as to render the
method altogether inapplicable.—_Bull. Univ._ A. viii. 248.
10. _On the apparent Decomposition of White Light by a Reflecting
Body when in Motion_.—The following experiment is described in the
MSS. of M. Benedict Prevost and published by M. P. Prevost. A ray
of solar light being introduced into a darkened chamber, is to have
a square piece of white paper about two inches in the side, passed
across it perpendicularly to the direction of the ray. The light
reflected by the paper, instead of being white, will present a small
white central portion, surrounded by the seven principal colours,
nearly in the order of the prismatic spectrum. When a red surface is
used instead of a white one, the decomposition of the light is still
more complete. When the paper has a slight blue tint, the effect
is less perfect than with the white paper. With a black surface no
colours appear, but a sort of smoky shade towards the middle. A
single passage of the paper is sufficient, but it is necessary that
it pass entirely through the ray, no part remaining in it.—_Bib.
Univ._—_Bul. Univ._ A. viii. 248.
11. _On the Barometer_.—The following are conclusions at which M.
Bohnenberger has arrived relative to the barometer: i. The surface
of mercury in a tube 14.5 lines in diameter, is slightly rounded at
the edge; but, at the distance of two lines from the glass, capillary
depression disappears, and the surface is level. ii. The mercury in
a tube 5.8 lines in diameter is convex over the whole surface, the
depression being .035 of a line. iii. The depression is generally
less in a vacuum than in the air, so that a syphon barometer gives
results too high, and the more so as the tube is smaller. iv.
Barometers constructed with tubes five lines in diameter, do not
require tapping to cause them to assume their proper height; and
comparatively slight blows easily make the mercury rise too high in
tubes of a smaller diameter.—_Annal. der Phys. und Chem._
12. _Easy Method of reducing Barometrical Observations to a Standard
Temperature, by_ S. Foggo.—The expansion of mercury deduced by the
different philosophers who have examined it, is given below; omitting
the results of Sir G. Shuckburgh, as being rather too far from the
mean of the others.
Expansion of mercury, from 32° to 212° F.
De Luc 1-56th }
Lavoisier and Laplace 1-55.22th }
Halstrom 1-55th } mean, 1-55.43th.
Dulong and Petit 1-55.5th }
[p459]
For 1° of Fahrenheit’s scale, this is equal to 1/9977.4, or
.00010023: which may be called one ten-thousandth, without the most
trifling error in practice. The barometric column may, therefore, be
reduced to the standard temperature of 32° F. by the following simple
rule, which will make a table unnecessary. _Before the first three
figures of the observed height place two cyphers, multiply by the
temperature of the mercury −32°, and subtract the product from the
observed height_. Example; barometer 30.597, temperature of mercury
74°.
74° − 32° = 42°.00305 × 42 = .128 and 30.597 − .128 = 30.469 the
correct height.
When the temperature of the mercury is lower than 32°, the
temperature is to be subtracted from 32°, and the product, obtained
as before, is to be _added_ to the observed height. Thus, let the
barometer be as before, and the temperature 15°: then 32° − 15° =
17°; .00305 × 17 = .052, and 30.597 + .052 = 30.649, the correct
height.—_Jameson’s Journal_, 1827, p. 378.
13. _Diamond Lenses_.—I see by the last number of the Journal of
Science and the Arts, that Mr. Varley has made a Diamond Lens, and
also a single microscope with such motions as enable the observer to
follow an animalcule in a diagonal direction. It is very odd, but
this is precisely my plan for a microscope, which I drew up about
four years ago; and as I could not get any optician to undertake it,
I sent it to the Society of Arts, and recommended them to offer a
premium for the best diamond lens, but they returned it. I have had
a microscope of this sort (made by W. and S. Jones, Holborn) about a
year and a half, and it answers the purpose completely; as a person
not at all used to microscopes may use a lens of 1/60 inch focus
and find a small object with it, and bring any part of it into the
field of view with the greatest facility, and follow the motions of
an animalcule in a diagonal direction. There are some alterations
and improvements, which I have since made, that have rendered it a
very complete microscope; a drawing of which I could send you, if you
think it would be acceptable.
I am, Sir, yours, &c.
_Tringham, Norfolk, July_ 9_th_, 1827. G. DAKIN.
14. _Sapphire Lenses for Single Microscopes_.—As it may justly
be feared that, notwithstanding the incontestable superiority
of diamond lenses, the cost and difficulty attendant on their
production will enhance their value beyond the reach of the public,
Mr. A. Pritchard, No. 18, Pickett Street, has applied himself with
indefatigable perseverance to the formation of _Sapphire Lenses_.
The valuable experiments of Dr. Brewster have determined that the
sapphire possesses a stronger refraction than any other substance
capable of giving a single image (diamond excepted), [p460] while
its dispersive power is only 0.026 compared to water as 0.035. Thus
if a sapphire is ground in the same tool which will form a lens
of glass of the 1/60 inch focus, it will come out about the 1/100
inch focus; being almost double the power of the glass in linear
amplification, and more than double in superficial; in which latter
mode of estimation the powers of the glass and sapphire may be rated
at 360,000 to 1,000,000. The faint blue tinge of the sapphire is not
felt in thin small lenses formed of this substance, which thus come
next in order to diamond ones, and form an excellent _pis aller_ for
those who cannot come at the latter. Many of our first microscopists
are already in possession of them, and have honoured them with their
unqualified approbation.
There is a property possessed by small single lenses formed by
precious stones, which is worthy of being commented on: viz. They
can be burnished fast into brass rings, and thus safely cleaned and
removed at pleasure from one setting to another. The cohesion of
glass is too slight to permit this operation, during which it is
almost sure to burst into shivers.—C. R. G.
15. _On a Method of Securing and Preserving the Rowing Pins in
Boats_.—Dear Sir,—To remove a petty inconvenience of hourly
occurrence, by some simple contrivance, is often productive of a
greater mass of advantage than an invention of greater splendour, and
of apparently more extensive utility.
[Illustration]
In the accompanying drawing, you have a plan for preserving that
indispensable requisite in a boat, the towels, or rowing pins; the
loss of which is not only very teasing, but often productive of
serious inconveniences; while the practice of stealing them from
each other forms a constant source of petty depredations, leading to
perpetual quarrels among seamen in harbours. He who has been detained
the better part of a day in the island of Sky, till half [p461] a
dozen of these pins could be procured, well knows how to value that
trifle, the neglect of which has caused the loss of his voyage, and
might have led to that of his boat and his life also.
Fixed towels cannot well be used when boats are to be hoisted in
alongside, as they are subject to be broken; and they are often
inconvenient in getting in water casks, as well as in many other
cases. Hence, pins capable of being unshipped are preferable. These
are frequently lost, and the want is not always discovered till it
cannot be replaced; or else it is not replaced without loss of that
time which is often so valuable at sea. Very often, also, the delay
of even a minute is rendered inconvenient or even dangerous; when the
boat is dragging alongside by the painter in a heavy sea, and the
vessel is either drifting or standing on.
The drawing requires little explanation. By pulling at the lower pin,
the two upper are fixed at once, and on being unshipped they hang
secure from loss; while the lower one serves us a spare towel, should
any be broken. As not one boat in twenty thousand is provided with
this invention, which is indeed scarcely known, it will not perhaps
be found undeserving a place in your Journal.—
I am, &c. J. M.
16. _Cold Injection for Anatomical Preparation_.—If a mixture of
varnish and vermilion has a small quantity of water mixed with it,
it soon sets and becomes hard. This affords an excellent composition
for anatomical injection, being very beautiful and very penetrating,
(so much so, that it frequently returns by the veins,) and requiring
no heat to be applied to the subject. The writer of this article
frequently had, in the course of his medical education, the office
of preparing this injection, of which he has, however, unfortunately
forgot the proportions, and the particular nature of the varnish. It
was, he thinks, a spirit varnish; the water was not mixed until the
instant the injection was wanted, when it was well worked up with the
syringe, and immediately thrown in; in the course of a night it would
have set beautifully. This particular kind of injection was invented
by an American anatomist of the name of Ramsay, and preserved as a
valuable secret by him for the exclusive use of his own dissecting
room. The proportions, &c. of the ingredients will soon be attained
by a few experiments.
II. CHEMICAL SCIENCE.
1. _Extraordinary Experiments on Heat and Steam by_ Mr. Perkins.—“I
discovered that a generator at a certain temperature, although it had
a small crack in it, would not emit either water or steam. This fact
I mentioned to a very scientific friend, who questioned its accuracy,
and to convince him I tried the experiment; but he concluded that the
expansion of the metal must have closed the fissure. To remove every
doubt, I proposed to drill a small [p462] hole through the side of
the generator, which was accordingly done. After getting the steam up
to a proper temperature, I took out the plug, and although we were
working the engine at thirty atmospheres, nothing was seen or heard
to issue from the plug-hole; all was perfectly quiet: I next lowered
the temperature by shutting the damper, and opening the furnace door;
a singing from the aperture was soon observable, and when a coal was
held before it, rapid combustion ensued; nothing, however, was yet
visible: but as the temperature decreased, the steam became more and
more visible, the noise at the same increasing, until finally the
roar was tremendous, and might have been heard the distance of half
a mile. This was conclusive. I should mention that, at the aperture,
the iron was red-hot.” “The hole was one _quarter of an inch_ in
diameter.”
“The experiment affords some data towards answering the question,
at what distance from the heated metal the water remained, when
under the pressure of thirty atmospheres; we may safely aver that it
exceeded one-eighth of an inch.”—_Silliman’s Journal_, xiii. 46.
2. _On the Use of feeble Electric Currents, for effecting the
Combination of numerous Bodies, by_ M. Becquerel.—A highly
interesting memoir on this subject is inserted in the thirty-fifth
volume of the _Annales de Chimie_, the intention of M. Becquerel
being to show that electro-chemical powers may be used not only for
the decomposition and analysis of bodies, but also for the production
of new compounds.
The facts described in the paper are commenced by one intended to
illustrate future reasoning, by shewing what takes place when a very
feeble electric current traverses a metallic circuit, interrupted in
one part by a neutral solution, into which the two extremities of
the wires forming the circuit are immersed. Two small copper wires
were connected together by loops, and the two free ends joined to the
ends of a galvanometer wire; the circuit was then cut in one place,
and the extremities immersed in a solution of chloride of sodium.
Then, if one of the loops be raised to a red heat by a spirit lamp,
an electric current is produced, the heated loop furnishing negative
electricity. Now if the ends plunged in the saline solution are
terminated by platina or gold wires, _no current_ of electricity is
observed; with silver terminations, the current is very feeble; but
with wires of zinc, lead, iron or tin, the current is very energetic.
These remarkable effects, highly important in the phenomena hereafter
to be considered, are no way connected with the conductibility of
the metals; for lead and zinc, which are the worst conductors, are
those which, with the copper, produce the most powerful effects. The
current ceases altogether as soon as the lamp is removed.
As the zinc, copper, lead, and iron, belong to the class of oxidable
metals, M. Becquerel concludes, from this experiment, that [p463]
when very feeble electricities are generated in any point of a
metallic circuit, interrupted by a saline solution, _a current of
electricity is formed or not, according as the two similar metallic
terminations, which dip into the solution, belong to an oxidable or
non-oxidable metal_. If the saline solution be replaced by an acid,
_then_ a current will be obtained, though platina wires be used;
because that kind of fluid does not interrupt the current.
With respect to the production of new compounds by electro-chemical
powers, very much depends upon the strength of the power employed,
and M. Becquerel only pretends, as yet, to indicate a new field of
research, and not to point out the precise paths to be pursued.
Two methods may be adopted. As an illustration, let a tube, from
4 to 8 hundredths of an inch in diameter, be bent into the form
of the letter U, and place a plug of amianthus at the bend, to
prevent the mixture of the fluids in the limbs: into one leg put
a mixture of deutoxide of copper and solution of the sulphate of
copper, the former will fall to the bottom; into the other put a
saturated solution of common salt, and also an excess of the dry
substance, then communicate the two fluids by a plate of copper.
Very shortly the end plunged in the sulphate will be covered with
metallic copper, and the acid set free will act upon the oxide of
copper below and form more sulphate, so that a set of decompositions
and recompositions will occur, and ultimately comparatively large
crystals of copper will be obtained.
In the other branch of the tube, a portion of the salt will be
decomposed, the muriatic acid will act upon the copper, which is
oxidised in consequence of its positive state, and will probably
produce an oxychloride, which will combine with the chloride of
sodium, and then octoedral crystals will be formed on the plate of
copper. The effects are produced either with or without access to air.
When the crystals are well dried and inclosed in a tube hermetically
sealed, they suffer no change; but they are decomposed by water into
chloride of sodium and submuriate of copper.
If the voltaic experiment be continued for one or two months, the
crystals, from being colourless and limpid, become violet, and
ultimately acquire an emerald green hue, still remaining transparent.
If the chloride of sodium side be tested, it will be found that soda
is evolved during the experiment. A piece of copper simply immersed
in a solution of common salt, produces nothing more than a submuriate
of copper, which precipitates.
_With silver_.—If a similar tube to that described have both limbs
filled with a solution of salt, a platina wire introduced into one
limb, a silver wire into the other, the extremities of the wire
connected so as to form a voltaic circuit, and the whole left for
some months, in about fifteen days crystals will be observed on the
silver wire; these will gradually increase and assume a rhomboidal
form. They have not yet been particularly examined, but [p464] are
known to be unchanged by water: during a long experiment they change
colour, becoming, first, violet, then blue.
Experiments similar to that with the copper, when repeated with the
same solutions, &c., but the substitution of plates of lead and tin
for the copper plates, produced crystalline double chlorides of these
metals and sodium.
Muriate of ammonia being substituted for common salt in these
experiments, another series of double compounds was obtained with
copper, silver, lead, and zinc.
A double chloride of barium and lead was formed slowly in a similar
way.
When a solution of the iodide of potassium or sodium was used instead
of the solution of salt, then double iodides were obtained: thus
with lead rather a rapid formation of silky crystals occurred upon
the lead, which, when examined by water, were decomposed, producing
iodide of lead and solution of iodide of potash or soda. A tube
two or three times the diameter of the former may be used for the
experiment.
The second method of producing new combinations by weak
electro-chemical powers, depends upon the electro-motive action,
which is caused whenever a metal touches the oxides, or an oxide
of another metal. If an oxide of a metal, a plate of metal, and a
liquid be put into a tube closed at one extremity, there will be an
electro-motive action of the metal with the oxide, and of the liquid
with both these bodies; and the chemical effect will be according to
the resultant of these three forces, which can only be ascertained by
experiments.
As an illustration of the effects thus produced, three tubes, from
eight to twelve hundredths of an inch in diameter, were prepared,
a little protoxide of lead being put into one, deutoxide into the
second, and peroxide into the third; solution of muriate of ammonia
and a plate of lead were then added to each tube. After a time, lead
was precipitated in the first tube, very slight chemical changes took
place in the second, but a large quantity of double chloride of lead
and ammonia crystallized upon the lead in the third, in the form of
needles. Thus very different effects were produced, according to the
state of oxidation.
Solution of salt gave similar results with the oxides of lead and
lead.
The oxides of copper, with solutions of alkaline muriates, gave
curious results. With muriate of ammonia, crystals were produced of
considerable size, and different to those obtained by the former
process. In this experiment, the black and anhydrous deutoxide of
copper gradually acquired a blue colour, as if a hydrate were formed
under the influence of the feeble electric current formed by the
arrangement.
Copper, its deutoxide, and solution of corrosive sublimate, produced
a double chloride, crystallizing in plates, and possessing a metallic
lustre. [p465]
3. _Crystallization of Metallic Oxides_.—If a solution of nitrate of
copper, mingled with very fine charcoal powder, or even deutoxide
of copper, be put into a similar tube to that described in the last
article, then a plate of copper be introduced and the vessel closed
up, in about fifteen days small red transparent octoedral crystals
of protoxide of copper will be formed on the plate of metal. Other
metals have been subjected to similar experiments, but probably have
not yet remained long enough under action.—_Ann. de Chimie_, xxxv.
113.
4. _On Bromine, by_ M. A. de la Rive.—M. de la Rive has remarked
a curious fact respecting the conducting power of fluids for
electricity in the habitudes of bromine and water. He found, in the
first place, as M. Balard had stated, that pure dry bromine did not
conduct the electricity of a voltaic battery, consisting of sixty
pairs of plates very strongly charged, a delicate galvanometer being
the test: a similar experiment was then made with pure water, the
water being contained in a glass capsule, and communicated with the
battery and galvanometer by platina wires[129], and the deviation
of the needle was scarcely sensible. Some other experiments induced
M. de la Rive to believe, that water perfectly distilled and put
into vessels made of substances absolutely unacted upon, would not
conduct any portion of electricity: the purer the water, and the
more unchangeable the substance of the vessel, the feebler does the
conducting power become, until at last it is insensible.
A few drops of bromine were then added to the water, which soon
acquired a yellow colour, by dissolving a small portion of
the substance; being now included in the voltaic circuit, the
galvanometer needle was deviated 70°, and an abundant disengagement
of gas took place from the platina wires. These were oxygen and
hydrogen, in the usual proportion, proving that the water only had
been decomposed.
From these experiments it results, that a body which does not at all
conduct voltaic electricity, or at least but very badly, namely,
_pure water_, may be rendered a very good conductor, by its mixture
with a few drops of perfectly _non-conducting_ substance, namely,
_bromine_. M. de la Rive has found the same fact to occur with
iodine, and iodine and water; and his father had observed, in a
course of experiments made a long time ago on the conducting power of
fluids, that diluted sulphuric acid is a better conductor than very
much concentrated acid: may not anhydrous sulphuric acid then be a
non-conductor like bromine, &c.?—_Annales de Chimie_, xxxv. 161.
FOOTNOTE:
[129] See, on this point, the statement by M. Becquerel, p. 462,
relative to the use of platina wires, when forming a communicating
medium with fluids.
5. _Elementary Nature of Bromine_.—Iodine colours a solution of
starch blue, bromine renders a similar solution orange colour. M.
A. de la Rive added a few drops of bromine to a solution of starch
[p466] coloured blue by iodine, and obtained a compound which gave
two distinct colours with starch, one brown, the other yellow; the
difference of colour corresponding with the two bromides of iodine
described by M. Balard. These compounds of iodine and bromine,
dissolved in a solution of starch, were subjected to the voltaic
pile: immediately the yellow solution became blue about the negative
pile, and orange about the positive pile, indicating the separation
and places of the iodine and bromine. Thus the smallest quantity of
iodine may be discovered in bromine; but when the experiment was
resorted to, to prove whether the idea thrown out, that bromine was a
compound of chlorine and iodine, was founded in fact or not, it gave
no such indication, and a solution of bromine in starch electrified
for a long time together, gave no appearance of iodine. Hence M. de
la Rive concludes, that bromine contains no iodine, but is an element
analogous to iodine and chlorine.
When bromine and iodine are combined, the former passes to the
positive pole, and is consequently more negative than the latter;
which accords with the observation of M. Balard, that it should
occupy a place between chlorine and iodine.
According to the _Bulletin Universelle_, when the letter to M. Arago,
containing an account of the facts above referred to, was read to
the Academy of Sciences, that body decided that the assertion of M.
Dumas that bromine was a compound of chlorine and iodine should be
considered as retracted, and that it should be so entered, upon the
procès-verbal of the sitting.—A. viii. 209.
6. _Quantity of Bromine in Sea-Water_.—One hundred pounds of
sea-water, taken up at Trieste, treated by chlorine, ether, &c.,
according to M. Balard’s process, produced five grains of bromide
of sodium, or 3.278 grains of bromine. It would appear that, in the
sea-water of Trieste, the bromine is unaccompanied by any iodine, and
the same is the case, according to M. Hermbstadt, with the waters of
the Dead Sea. In the water of the Mediterranean, on the contrary,
iodine always appears with the bromine.
7. _Sale of Bromine_.—The discoverer of bromine, M. Balard, has
been enabled, by his improvements, to prepare that peculiar body
in quantities sufficient to permit its sale. It may be obtained
at his shop, Rue Argenterie à Montpellier, or at M. Quesneville’s
manufactory of chemical substances at Paris. The price is four francs
the gros (about 60 grains), fourteen francs the half ounce, and
twenty-three francs the ounce.
8. _Preparation of Iodous Acid_.—M. Pleischl says that, in preparing
this acid, three parts of chlorate of potash with one of iodine are
to be used, and not equal parts according to M. Sementini; and also
that it is indispensable to cool the receiver considerably during the
whole operation. [p467]
9. _On a peculiar Nitric Acid, and Sulphate of Potash, by_ Mr.
Phillips.—For the purpose of preparing nitric acid of the greatest
strength, Mr. Phillips mixed 70 parts of nitre with 70 parts of oil
of vitriol, S. G. 1.8442 at 60°, and distilled for eight hours. The
nitric acid obtained was reddish yellow, weighed 46.13 parts, was of
S. G. 1.5033, and by an experiment on carbonate of lime, was found
equivalent to 34.24 of that substance; the latter fact indicates
that 36.98 of real acid was present, and the liquid acid therefore
consisted of
Real nitric acid 36.98 or 80.16
Water 9.15 19.84
----- ------
46.13 100.00
Supposing this acid to be a definite compound of two atoms of acid,
108, and three of water 27, it would consist of
Real acid 36.90 or 80
Water 9.23 20
----- ---
46.13 100
The salt remaining in the retort weighed 92.87 parts; nearly this
weight of water being added and heated, the whole was dissolved,
and on cooling, a salt, consisting of extremely minute filaments
resembling asbestos, was obtained, which, by capillary attraction,
retained a part of the residual solution so powerfully, that it was
necessary to absorb it by filtering paper.
Although it appeared improbable that the crystals could be a variety
of the known form of bisulphate of potash, yet supposing it might
be that salt with either less, or more than two atoms of water, Mr.
Phillips proceeded to its analysis. Some of the salt was readily
dried by exposure to the air of a warm room: 100 grains, by muriate
of baryta gave 154.75 grains of sulphate of baryta, equivalent
to 52.45 sulphuric acid: 109 grains heated to redness, lost 21.6
sulphuric acid and water, and left 78.4 grains of neutral sulphate
of potash. The latter contain 35.6 grains of sulphuric acid, which,
subtracted from the whole quantity of 52.45, indicates 16.85 as the
quantity dissipated by heat; and this again, subtracted from the
21.6, indicates 4.75 water in the crystals. The quantity of acid
separated by heat is, therefore, very nearly half that remaining
in the neutral sulphate, and the salt in question appears to be a
sesquisulphate of potash, consisting of
theory. experiment.
3 atoms sulphuric acid 120 55.33 52.45
2 " potash 96 42.66 42.80
1 atom water 9 4.00 4.75
--- ----- ------
225 99.99 100.00
Mr. Phillips found it difficult to prepare the sesquisulphate free
[p468] from bisulphate; and on repeating the attempt to procure it
exactly as before, obtained a large quantity of bisulphate, and a
small quantity of the peculiar salt; although the quantity of water
present is known to have an important influence on the nature of
the sulphates produced, yet the precise circumstances on which the
formation of sesquisulphate depends, are at present unknown.—_Phil.
Mag. N. S._, ii. 429.
10. _On certain Properties of Sulphur_.—The effect of heat upon
sulphur in first fusing it, but afterwards causing diminution of
fluidity in a certain degree proportionate to the temperature, has
been long and generally known, as well also as the peculiar soft
state into which the sulphur may be brought, by pouring it, when hot
and thickened, into cold water. M. Dumas has been led to examine
these phenomena for the purpose of acquiring a precise and particular
knowledge of the effects and changes.
Fused sulphur began to crystallize between 226° and 228°. Its fusing
point may be considered as 226°.4. Between 230° and 284° it is as
liquid as a clear varnish, and of the colour of amber; at about 320°
it begins to thicken, and acquire a red colour; on increasing the
heat, it becomes so thick, that it will not pour. This effect is most
marked between 428° and 572°; the colour being then a red-brown. From
572° to the boiling point it becomes thinner, but never so fluid as
at 248°. The deep red-brown colour continues until it boils.
When the most fluid sulphur is suddenly cooled, it becomes brittle,
but the thickened sulphur, similarly treated, remains soft, and more
soft as the temperature has been higher. Thus, at 230°, the sulphur
was very liquid, and yellow; and cooled suddenly by immersion in
water, it became yellow and very friable; at 374° it was thick,
and of an orange colour, but by cooling, became at first soft and
transparent, but soon friable, and of the ordinary appearance; at
428°, it was red and viscid, and when cooled, soft, transparent,
and of an amber colour; at the boiling point it was deep brown red
colour, and when cooled very soft, transparent, and of a red-brown
colour.
It is not necessary, as is sometimes stated, to heat the sulphur a
long time to produce this effect; all depends upon temperature. The
only precaution necessary is, to have abundance of water, and to
divide the sulphur into small drops or portions, that the cooling may
be rapid. If it be poured in a mass, the interior cools slowly, and
acquires the ordinary hard state. When the experiment is well made at
446°, the sulphur may be drawn into threads as fine as a hair, and
many feet in length.
M. Dumas, in remarking upon this curious effect of sudden cooling,
classes it with the similar effect which occurs with bronze. Although
difficult to assign the exact cause, yet he notices that the tendency
to crystallize can evidently be traced as influential over some of
the appearances, the hardness and opacity, for instance, [p469]
which always occur together when the crystalline state is assumed;
whereas, when rapid cooling has hindered crystallization, the mass
remains soft and transparent, until it crystallizes, which usually
happens in twenty or thirty hours.—_Ann. de Chimie_, xxxvi. 83.
11. _On the Fluidity of Sulphur and Phosphorus at common
temperatures_, by Mr. Faraday.—I published some time ago a short
account of an instance of the existence of fluid sulphur at common
temperatures[130]; and though I thought the fact curious, I did not
esteem it of such importance as to put more than my initials to
the account. I have just learned, through the _Bulletin Universel_
for September, p. 178[131], that Signor Bellani had observed the
same fact in 1813, and published it in the _Giornale di Fisica_,
vol. vi. (old series). I also learn, by the same means, that M.
Bellani complains of the manner in which facts and theories, which
have been published by him, are afterwards given by others as new
discoveries; and though I find myself classed with Gay-Lussac, Sir
H. Davy, Daniell, Bostock, &c., in having thus erred, I shall not
rest satisfied, without making restitution, for M. Bellani, in this
instance, certainly deserves it at my hand.
Not being able to obtain access to the original journal, I shall
quote M. Bellani’s very curious experiments from the Bulletin, in
which they appear to be fully described. “The property which water
possesses, of retaining its fluid states, when in tranquillity, at
temperatures 10° or 15° below its freezing point, is well known;
phosphorus behaves in the same manner; sometimes its fluidity may
be retained at 13° (centigrade?) for a minute, an hour, or even
many days. What is singular is, that, though water cooled below
its freezing point, congeals easily upon slight internal movement,
however communicated, phosphorus, on the contrary, sometimes retains
its liquid state even at 3°, even though it be shaken in a tube or
poured upon cold water. But, as soon as it has acquired the lowest
temperature which it can bear without solidifying, the moment it
is touched with a body at the same temperature, it solidifies so
quickly, that the touching body cannot penetrate its mass. If the
smallest morsel of phosphorus is put into contact with a liquified
portion, the latter infallibly solidifies, though it be only a single
degree below the limit of temperature necessary; this does not always
happen when the body touching it is heterogeneous.
“Sulphur presented the same phenomena as phosphorus; fragments of
sulphur always produced the crystallization of cold fluid portions.
Having withdrawn the bulb of a thermometer which had been plunged
into sulphur at 120°, it came out covered with small globules of
sulphur, which remained fluid at 60°; and having touched these one
after another with a thread of glass, they became solid: although
several seemed in contact, yet it required that each [p470] should
be touched separately. A drop of sulphur, which was made to move
on the bulb of the thermometer, by turning the instrument in a
horizontal position, did not congeal until nearly at 30°; and some
drops were retained fluid at 15°, _i. e._ 75° of Reaumur below the
ordinary point of liquefaction.”
The _Bulletin Universel_ then proceeds to describe some late and new
experiments of M. Bellani, on the expansion in volume of a cold dense
solution of sulphate of soda during the solidification of part of the
salt in it. The general fact has, however, been long and well known
in this country and in France; and the particular form of experiment
described is with us a common lecture illustration. The expansion, as
ascertained by M. Bellani, is 2/87 of the original volume of fluid.
According to the Bulletin, M. Bellani also claims, though certainly
in a much less decided manner than the above, the principal ideas
in a paper which I have published on the existence of a limit to
vaporization, and I referred back to the _Giornale di Fisica_ for
1822, (published prior to my paper,) for the purpose of rendering
justice in this case also. Here, however, the contact of our ideas
is so slight, and for so brief a time, that I shall leave the papers
in the hands of the public without further remarks. It is rather
curious to observe how our thoughts had been at the same time upon
the same subject. Being charged in the Bulletin with quoting an
experiment from a particular page in M. Bellani’s memoir, (which
I did from another journal, in which the experiment only was
described,) I turned to the original place, and there, though I found
the experiment I had transferred, I also found another which I had
previously made on the same subject, and which M. Bellani had quoted.
I very fully join in the regret which the _Bulletin Universel_
expresses, that scientific men do not know more perfectly what has
been done, or what their companions are doing; but I am afraid the
misfortune is inevitable. It is certainly impossible for any person
who wishes to devote a portion of his time to chemical experiment, to
read all the books and papers that are published in connexion with
his pursuit; their number is immense, and the labour of winnowing out
the few experimental and theoretical truths which in many of them
are embarrassed by a very large proportion of uninteresting matter,
of imagination, and of error, is such, that most persons who try the
experiment are quickly induced to make a selection in their reading,
and thus inadvertently, at times, pass by what is really good.
FOOTNOTES:
[130] Quarterly Journal of Science, xxi. 392.
[131] The Italian Journal has not yet arrived in this country.
12. _Separation of Selenium from Sulphur_.—Berzelius says, that
these substances, so much resembling each other in their general
properties, may be easily separated by the following process. When
sulphuret of selenium is fused with carbonate of potash, the alkali
not being excess, the fused mass, dissolved in water, leaves selenium
undissolved and free from sulphur. [p471]
Some of the sulphuret of selenium from Lukawitz, in Bohemia, was
dissolved in potash, and the solution converted into hyposulphite
by exposure to the air at the temperature of 65° F.; 0.1125 of the
sulphuret experimented with were precipitated, and found to be _pure
selenium_. The solution being of a deeper red colour than that of the
common sulphuret, a piece of sulphur was put into it, and the whole
boiled for a moment; a quarter of a grain of selenium, perfectly free
from sulphur, was precipitated.
A solution of a neutral seleniate, or of one with excess of base,
is soon rendered turbid by having sulphuretted hydrogen passed
through it. At first pure selenium separates; afterwards sulphuret
of selenium; and, lastly, mere sulphur. The solution should be
considerably diluted; when concentrated, the precipitate formed
is of a flame yellow colour, but soon becomes brownish-black, and
sulphur is deposited, sometimes crystallizing at the surface of the
deposite.—_Phil. Mag., N. S._, ii. 390.
13. _On a new Compound of Selenium and Oxygen—Selenic Acid, by_
MM. Mitscherlich and Nitzsch.—This acid contains half as much more
oxygen as that discovered by M. Berzelius, and with potash forms a
neutral salt, having the same form and optical properties as sulphate
of potash, containing no water when crystallized, and producing
insoluble precipitates with barytic salts. The acid is isomorphous
with the sulphuric, and may with propriety be called _selenic acid_,
that described by M. Berzelius being considered as the _selenious
acid_.
The new acid is easily prepared: for this purpose selenium, selenious
acid, a selenite or a metallic selenuret is to be fused with nitre.
Selenuret of lead, being the most abundant source, has been used for
this purpose, but being accompanied by sulphuret, the selenic acid
is usually contaminated by sulphuric acid. The selenuret of lead
is to be freed from carbonates by muriatic acid, and the residue
mixed with its weight of nitrate of soda, and thrown gradually into
a red-hot crucible. Water then dissolves out seleniate nitrate and
nitrite of soda, no selenium remaining in the residue. The solution
quickly boiled, deposits anhydrous seleniate of soda, and this being
separated, by cooling crystals of nitrate of soda are formed; these
being removed, ebullition again causes more seleniate to fall down,
and proceeding in this way an imperfect separation is effected. The
seleniate, like the sulphate of soda, is most soluble in water at
181°. To purify the salt completely, the nitrite should be changed
into nitrate by nitric acid; but then sulphate of soda would remain
as an impurity formed from sulphuret in the ore, and no attempt to
separate this has as yet succeeded.
But if the seleniate of soda be mixed with muriate of ammonia and
heated, selenium, nitrogen and water come over, no trace of sulphur
appearing. The selenium may, however, be dissolved in excess of
nitric acid, and the selenious acid produced tested by [p472]
muriate of baryta, which would then separate sulphuric acid if
present; the clear solution is to be saturated with carbonate of
soda, evaporated to dryness, and the mixture of selenite and nitrate
of soda obtained, fuzed in a porcelain crucible over a spirit-lamp.
Then proceed by crystallization as before, and a pure seleniate of
soda will be produced.
To separate the selenic acid, the solution is to be decomposed
by nitrate of lead; the seleniate of lead is as insoluble as the
sulphate, and being well washed, is to be decomposed by a current
of sulphuretted hydrogen, which has no action on the selenic acid;
the solution being filtered, is to be boiled, and is then diluted
selenic acid. Its purity, as respects fixed bodies, is ascertained
by its entire volatility; if sulphuric acid be present, it may be
ascertained by boiling a portion with muriatic acid, which produces
selenious acid, and then testing by muriate of baryta, a precipitate
indicates sulphuric acid.
From the isomorphism of selenic acid and its salts with sulphuric
acid and its salts, M. Mitscherlich concluded, that the oxygen in the
acid should be to that in selenious acid as 3 to 2; and to that in
bases when it forms salt, as 3 to 1. These views were confirmed by
experiments. From the decomposition of seleniate of potash by muriate
of baryta, it appeared that the seleniate was composed of
Potash 42.16 oxygen 7.15
Selenic acid 57.84 ---- 21.79
------
100.00
The composition of the acid was determined by boiling a certain
weight of the seleniate of soda with muriatic acid in excess, and
decomposing the selenious acid formed by sulphite of soda; 4.88 of
the salt gave 2.02 of selenium, from which, and the above result, it
would appear that the acid is formed of
Selenium 61.4
Oxygen 38.6
-----
100.0
According to Berzelius, selenious acid consists of 100 selenium, and
40.33 oxygen; and supposing this contains two-thirds the oxygen in
selenic acid, the latter should consist of 62.32 and 37.68. From the
analysis above given of the seleniate of potash, it is evident that
100 of selenic acid saturates a quantity of base captaining 12.56 of
oxygen, which would agree with the latter estimate of selenic acid.
_Selenic acid_ is a colourless liquid, which may be heated to 536°,
without sensible decomposition; above that it changes, and is,
rapidly resolved into oxygen and selenious acid at 554°. Heated to
329°, its specific gravity is 2.524; at 512°.6 it is 2.6; at 509°
it is 2.625; but by that time selenious acid has been formed in it.
A portion of concentrated acid, from which the selenious acid had
[p473] been removed, consisted of 84.21 selenic acid, and 15.75
water; but it is certain that the selenic acid begins to decompose
before it has resigned the last portions of water.
Selenic acid has a powerful attraction for water, and evolves much
heat when mixed with it. It is not decomposed by sulphuretted
hydrogen; so that the latter body may be used to decompose the
seleniates of lead and copper. When boiled with muriatic acid it
produces selenious acid and chlorine, and the mixture, like aqua
regia, will dissolve gold or platina. Selenic acid dissolves zinc
and iron, evolving hydrogen; it dissolves copper, evolving selenious
acid; and it dissolves gold, but not platina. Sulphurous acid has no
action on selenic acid, but instantly decomposes the selenious acid.
A solution containing selenic acid is easily decomposed, by first
boiling it with muriatic acid, and then adding sulphurous acid.
Selenic acid is but little inferior to sulphuric acid in its affinity
for bases; seleniate of baryta is not completely decomposed by
sulphuric acid. Its combinations being isomorphous with those of
sulphuric acid, and possessing the same crystalline forms, and the
same general chemical properties, present but very slight, though
very interesting differences from the sulphates. These will be
resumed by M. Mitscherlich in a future memoir, with the express
object of illustrating the theory of Isomorphism.—_Ann. de Chimie_,
xxxvi. 100.
14. _Preparation of Hyposulphuric Acid_.—According to M. Heeren, to
obtain the greatest quantity of this acid in the process of passing
sulphurous acid over black oxide of manganese, the temperature
should be low, and the oxide finely divided. The largest portion of
hyposulphuric acid is formed at the commencement of the operation.
15. _Singular Habitude of Phosphoric Acid with Albumen_.—MM.
Berzelius and Englehart differed in their results respecting the
effect of phosphoric acid on albumen; the latter found the acid
caused precipitation of the substance, the former the reverse.
Fortunately coming into company, they made some experiments, and
discovered a very singular property of the acid. The acid in
Berzelius’s laboratory not precipitating albumen, Dr. Englehart
prepared a fresh portion from phosphorus and nitric acid, evaporating
the solution in a platina vessel, and heating it to redness. This
acid, dissolved in water, precipitated both animal and vegetable
albumen abundantly. Another portion of acid, prepared by burning
phosphorus in air, also precipitated albumen. After many experiments
to discover the cause of difference in the acids, Dr. Englehart
remarked, that the two acids he had prepared, gradually lost their
power of precipitating albumen, and in some days were like the acid
of Berzelius. This change took place both in open and closed vessels,
and was not at all hastened by ebullition. [p474] Upon evaporating
the acid, and heating it to redness, it recovered its precipitating
power, but gradually lost it again by a day’s repose. The cause of
this difference escaped detection; it evidently does not depend upon
a difference of oxidation. “May it not be supposed,” says Berzelius,
“that there exists a chemical combination of phosphoric acid with
water, which is not formed until some time after solution, and which
is incapable of precipitating albumen?”—_Annales de Chimie_, xxxvi.
110.
16. _Economical Preparation of Deutoxide of Barium_.—This process is
due to M. Quesneville. Nitrate of baryta is to be put into a luted
earthenware retort, to which a tube is to be attached for the purpose
of conveying the liberated gases to a water-trough. The retort is
to be gradually heated to redness, and retained at that temperature
as long as nitrous acid and azotic gas pass over; the evolution of
these substances indicates that nitrate of baryta still remains to
be decomposed, but the instant that pure oxygen gas passes off, the
fire is to be removed and the retort cooled. The product of this
decomposition is a peroxide of barium; it falls to pieces in water,
without producing heat, disengages oxygen when boiled with water,
and is reduced to a protoxide by a strong heat. When acted upon by
sulphuric acid, no nitric acid was evolved; and when subjected to
nitric acid, no nitric oxide was produced. The production of this
peroxide is easily understood, for the protoxide formed by the
decomposition of the nitrate being in contact, at a red heat, with a
large quantity of oxygen in a nascent state, combines with it, and is
retained, unless the heat be so high as to decompose it.—_Annales de
Chimie_, xxxvi. 108.
The decomposition and effect are precisely the same as those lately
pointed out by Mr. Phillips as occurring with potassium when the
nitrate of potash is decomposed by heat.—See p. 483 of the last
volume of this Journal.
17. _Preparation of Aluminum—Chloride of Aluminum_.—According to
the accounts published, the following process has succeeded in
the hands of M. Oersted, in decomposing alumina and evolving the
base _aluminum_. Pure alumina is to be heated to redness, and then
well mixed with pulverized charcoal; the mixture is to be placed
in a porcelain tube, and being heated to redness, is to have dry
chlorine gas passed over it; the charcoal reduces the alumina, the
base combines with the chlorine, and oxide of carbon is formed.
The chloride of aluminum is soft, crystalline, and evaporates at
a temperature a little above 212° Fahrenheit: it readily attracts
moisture from the atmosphere, and becomes hot when water is added
to it. Being mixed with an amalgam of potassium, containing much
of the latter metal, and immediately heated, chloride of potassium
is formed, and the metallic base of the alumina combines with the
mercury. The amalgam quickly oxidises by exposure to air; but being
heated out of contact with the atmosphere, the mercury is [p475]
volatilized, and a metallic button is left, having the colour and
splendour of tin. A fuller account of the researches of M. Oersted on
this subject is expected.—Hensmann’s _Repertoire—Phil. Mag. N. S._ ii.
18. _Mutual Action of Lime and Litharge_.—M. Fournet heated a
mixture consisting of 7.12 parts of calcined lime, and 27.89 parts
of litharge, very strongly; a coherent mass was obtained, which,
pulverized and digested in water, gave, when filtered, a perfectly
clear and colourless liquor, which, when treated with sulphuretted
hydrogen, threw down an abundant black precipitate: hence oxide of
lead is rendered soluble in water by means of lime.—_Ann. des Mines_,
i. 538.
19. _New Chloride of Manganese discovered by_ M. J. Dumas.—This
chloride corresponds in proportions to the manganesic acid, and in
contact with water, produces muriatic and manganesic acids. It is
easily obtained by putting a solution of manganesic acid into contact
with concentrated sulphuric acid, and fused common salt. Water and
the new chloride are formed; the former is retained by the acid, the
latter volatilizes in a gaseous form. The body does not, however,
appear to constitute a permanent gas[132], for though, when produced,
it appears as an elastic fluid having a cupreous or greenish tint,
yet when passed into a tube, cooled to 5° or 4° Fahrenheit, it
condenses into a liquid of a brownish green colour.
When the perchloride is produced in a large tube, its vapour
gradually displaces the air present, and the tube becomes filled
with it; if it then be poured into a jar with moistened sides, the
colour of the gas changes as it comes into contact with the moist
air; a thick smoke of a fine rose colour appears; and the sides of
the vessel acquire a deep purple colour due to the manganesic acid
formed. The water thus coloured is abundantly precipitated by nitrate
of silver, and, acted upon by a solution of potash, produces all the
changes of the mineral chamelion.
The most simple process for the preparation of this body appears to
be to form a common green chamelion, to convert it into red chamelion
by sulphuric acid, and to evaporate the solution, which will give
a residue consisting of sulphate and manganesate of potash. This
mixture, acted upon by concentrated sulphuric acid, produces the
solution of manganesic acid, into which the common salt is to be
thrown in small pieces, until the vapours which rise are colourless;
the latter effect is a sign that all the manganesic acid is
decomposed, and that muriatic acid only is produced.
An analogous compound is formed when a fluoride is used in place of
the common salt. But all attempts as yet made to collect a sufficient
quantity for examination have failed; the chloride, on the contrary,
is easily formed and examined, although it is not so easy to preserve
it.—_Annales de Chimie_, xxxvi. 81. [p476]
FOOTNOTE:
[132] Query, what is a permanent gas?—ED.
20. _Preparation of pure Oxide of Zinc, by_ M. Hermann.—It is by no
means easy to obtain this substance perfectly pure; the following
is M. Hermann’s process: Oxide of zinc, or metallic zinc, is to
be dissolved in excess of sulphuric acid, and the solution being
filtered, sulphuretted hydrogen is to be passed through, so long
as a brown or yellow precipitate is formed. Cadmium, lead, or
copper, being thus separated, and the solution filtered, it is to be
treated with solution of the chloride of lime, (bleaching powder,)
by which the iron and manganese will be separated. The solution,
again filtered, is then to be crystallized in porcelain vessels, by
which sulphate of lime is rejected, and a mother liquor separated,
which usually contains cobalt and nickel. The crystals of sulphate
of zinc are to be dissolved in as small a quantity of cold water as
possible, and the sulphate of lime filtered out; then the solution,
being rendered more dilute, is to be decomposed by carbonate of
soda in slight excess, and the precipitate well washed, dried, and
heated to redness: it is then a perfectly pure and beautifully white
oxide.—_Bull. Univ._ A. viii. 263.
21. _Deuto-Sulphuret of Cobalt_.—Mix finely divided oxide of
cobalt with three times its weight of sulphur, and heat to very
dull redness, until no more sulphur sublimes. The deuto-sulphuret
consists of 100 cobalt + 109 sulphur; it is black; is reduced to gray
proto-sulphuret by a strong heat.—_Sitterberg_.
22. _Separation of Bismuth from Mercury by Potassium_.—M. Serullas
has pointed a striking instance of the separation of bismuth from
mercury. He says a twelve hundred thousandth, and even less of
bismuth, when dissolved in mercury, may be separated and rendered
visible by the addition of a certain quantity of the amalgam of
potassium and a little water. A black powder is observed to rise from
the substance of the metal, and is a mixture of bismuth and mercury
in a very divided state; it rises to the surface or adheres to the
vessels.
Copper, lead, tin, and silver, are equally separated, but not so
promptly, or so evidently to the eye as bismuth; for they are not
associated with divided mercury, at the time of their separation,
like the latter: with bismuth a mere atom is rendered visible, and M.
Serullas thinks that chemistry does not present a more delicate test
than the amalgam of potassium for bismuth in mercury.—_Annales de
Chimie_, xxxiv. 195.
23. _Sulphuret of Arsenic proportionate in Composition to Arsenic
Acid_.—M. Pfaff acted upon arsenious acid by nitro-muriatic acid,
and obtained a pure arsenic acid soluble in water, and deliquescent
in the air. This, dissolved in 40 parts of water, had a current of
sulphuretted hydrogen passed through it, which instantly produced a
yellow orange precipitate of a pulverulent form, continuing identical
in composition, until no further precipitate was [p477] occasioned.
The fluid was then perfectly free from arsenic. The precipitate was
pure sulphuret of arsenic, soluble in ammonia when slightly heated,
and composed of equal parts of sulphur and the metal.
M. Pfaff further says that arsenic acid may be separated from its
combinations with bases, by dissolving the arseniates in nitric acid,
and passing sulphuretted hydrogen through the solution; an abundant
precipitate of sulphuret of arsenic is formed, containing no trace of
the base of the arseniate decomposed.—_Bull. Univ._ A. viii. 256.
24. _New Double Chromates_.—Mr. Stokes has obtained several new
salts, by mixing chromate of potash with metallic sulphates. Chromate
of potash, mixed with sulphate of zinc, gave a precipitate of
chromate of zinc; and the mother liquor, by concentration, yielded
certain yellow crystals in the form of a flat rhombic prism, which
Dr. Thomson had mistaken for impure sulphate of zinc, but which Mr.
Stokes recognised as a new compound: 50 grains gave 18.33 sulphuric
acid; 0.18 chromic acid; 9.87 oxide of zinc; 8.91 potash; 12.6 water:
0.11 loss.
Chromate of potash and sulphate of nickel were mixed in atomic
proportions, and the solutions heated; after the chromate of nickel
was separated, they were evaporated to dryness. The residuum,
digested in water, was filtered, and the deep red solution obtained
upon cooling, yielded grass green crystals in the form of oblique
rhombic prisms; 50 grains of these, when analysed, gave 12.26
sulphuric acid; 0.978 chromic acid; 8.2 oxide of nickel; 9.862
potash; 12.7 water.
A similar salt may be obtained by mixing chromate of potash and
sulphate of copper. It is of a light green colour, and has precisely
the same form as the salts already described. In every case
crystals of bichromate of potash were produced in the second crop
crystals.—_Phil. Mag. N. S._ ii. 427.
25. _Dobereiner’s finely divided Platina_.—The following is M.
Dobereiner’s process for obtaining finely divided platina, fit
for the performance of the experiment which he first made on the
combination of oxygen and hydrogen, at common temperatures. Mix
muriate of platina with a solution of neutral tartrate of soda in
a glass tube, half or three-quarters of an inch in diameter, and
twenty or thirty inches in length, and apply heat until the fluid
becomes slightly turbid; afterwards expose it for several days to
the sun’s rays. The greater part of the platina will separate from
the solution, and be deposited in minute laminæ, of a greyish black
colour on the sides of the glass; the tube and its contents are
to be put into a glass vessel containing water, and it is to be
filled with hydrogen gas; the platina becomes almost immediately
white and shining like silver, and may then be readily detached
from the glass. During the reduction of the platina the tartaric
acid is partly converted into carbonic and formic acids. “As the
inflammation [p478] of the hydrogen,” it is said, “is caused by
abstracting a portion of the caloric from the oxygen, effected by
the platina, the smaller the laminæ of the metal are, the more
readily is the incandescence produced.” Spongy platina for the lamps
for instantaneous light, is prepared of great power, by moistening
the muriate of ammonia and platina with a concentrated solution of
ammonia; the paste formed is to be heated to redness in an earthen or
platina crucible.—_Hensman’s Repertoire—Phil. Mag. N. S._ ii. 388.
26. _New Metals_.—Professor Osann, of Dorpat, is said to have
discovered three new metals in the crude platina, obtained from the
Uralian mountains. One, which has occurred only in one specimen of
the ore, resembles osmium in some of its compounds. The second forms
white acicular crystals from a nitro-muriatic acid solution; these,
when heated, being softened and reduced. The third is insoluble in
nitro-muriatic acid, and, by a particular process yields a dark
green-coloured oxide. The account as yet given of these substances is
not precise enough to allow of any judgment respecting their claim to
the character of new metals.
27. _Analysis of Porcelain, Pottery, &c., by_ M.
Berthier.—Earthenware manufactures are divided by M. Berthier
into three kinds, those of 1. Porcelain; of 2. Pottery; and of 3.
Crucibles, Bricks, &c. The following is the composition of certain
porcelains:
PORCELAIN.
Sèvres. English. Piedmont. Tournay.
(i.) (ii.) (iii.) (iv.)
Silica 0.596 0.770 0.600 0.753
Alumina 0.350 0.086 0.090 0.082
Potash 0.018 .. .. 0.059
Soda .. .. .. 0.059
Lime 0.024 0.012 0.016 0.100
Magnesia 0.070 0.152 ..
Water 0.008 0.056 0.136 0.006
----- ----- ----- -----
0.996 0.994 0.994 1.000
(i.) Sèvres service—Paste strongly heated. It is formed from 0.63
washed kaolin of Limoges; 0.105 quartz sand; 0.052 Bougeval chalk;
0.21 of the fine sand obtained from kaolin by washing, and which is
a mixture of quartz and felspar. The glaze of this ware is made of a
rock composed of quartz and feldspar. When reduced to a fine powder,
it is found to be composed of silica .730, alumine 162, potash 84,
water 6: it fuses into a perfectly transparent and colourless glass.
(ii.) Worcester porcelain—Paste taken from the workshops, unbaked.
(iii.) Porcelain of Piedmont—Paste dried. The base of this
manufacture is the _magnesite_ of Baldissero.
(iv.) Porcelain of Tournay—Clay, chalk, and soda enter into its
composition. It is very fusible, but not very fragile. [p479]
POTTERY.
Nevers. Paris. Gergovia.
(i.) (ii.) (iii.)
Silica 0.572 0.541 0.544
Alumina 0.124 0.127 0.220
Lime 0.226 0.063 0.064
Oxide of Iron 0.066 0.070 0.098
Magnesia .. 0.024 0.038
Water .. 0.173 0.020
----- ----- -----
0.988 0.998 0.984
(i.) Earthenware of Nevers—Paste of a pale red. Made of a marle
occurring close to the town; the glaze is a white enamel, containing
both tin and lead.
(ii.) Paste of the brown earthenware made by M. Husson at Paris. The
biscuit is red, but is covered by a brown glaze, coloured by oxide of
manganese.
(iii.) Red earthenware resembling the Etruscan, and found in the
ruins of Gergovia near Clermont.
CRUCIBLES, &C.
St.
Hessian. Paris. English. Etienne.
(i.) (ii.) (iii.) (iv.)
Silica 0.709 0.646 0.637 0.652
Alumina 0.248 0.344 0.207 0.250
Oxide of Iron 0.038 0.010 0.040 0.072
Magnesia trace .. .. trace
Water .. .. 0.103 ..
----- ----- ----- -----
0.995 1.000 0.987 0.974
Le
Nemours. Bohemia. Creusot.
(v.) (vi.) (vii.)
Silica 0.674 0.680 0.680
Alumina 0.320 0.290 0.280
Oxide of Iron 0.008 0.022 0.020
Magnesia trace 0.005 trace
Water .. .. 0.010
----- ----- -----
1.002 0.997 0.990
(i.) Hessian crucibles—formed of a clay very aluminous, with which
siliceous sand is mixed. They sustain rapid changes of temperature
without fracture, but cannot retain fused litharge very long
together, and have too coarse a grain for many purposes.
(ii.) Paris crucibles, manufactured by Beaufaye—they are made from
the clay of Andennes, near Namur; part of the material being baked
and coarsely powdered, and the rest in its natural state: no sand
is mixed with it, and the inner surface of the vessels is finished
with a thin coat of the unbaked material. They are said to be more
refractory than the Hessian vessels, not more liable to fly by change
of temperature, and more retentive of litharge.
(iii.) Fragment of an unbaked crucible prepared for an English
cast-steel work.
(iv.) Paste with which the crucibles are made for the steel works of
Berardière, near St. Etienne.
(v.) Fragment of a used crucible from the glass works of Bagneaux,
near Nemours; it had been made from the clay of Forges (Seine
Inférieure).
(vi.) A used crucible from a Bohemian glass-house.
(vii.) Bricks with which the blast furnaces at Creusot are [p480]
constructed; they are made of a mixture of baked and unbaked
clay.—_Annales de Chimie_, i. 469.
28. _On the Composition of simple Alimentary Substances, by_ Dr.
Prout.—It is well known that Dr. Prout has of late years devoted that
portion of his attention which he gives to chemistry, exclusively
to the consideration of organized substances, with the important
object of making the knowledge he might obtain subservient to the
study of physiology and pathology; and during the last session of the
Royal Society, a paper by this philosopher was read, containing many
important and apparently accurate results relative to the particular
subjects which he has pursued; some account of which we are desirous
of giving in this place.
Dr. Prout’s first object was to devise, if possible, an
unexceptionable mode of determining the proportions of the three or
four principles, which, with few exceptions, form organic bodies;
and after numerous trials, he adopted a method founded upon the
following well known principles. When an organic product, containing
three elements, hydrogen, carbon, and oxygen, is burnt in oxygen
gas, one of three things must happen: i. The original bulk of oxygen
gas may remain the same, in which case the hydrogen and oxygen in
the substance must exist in it in the same proportions in which
they exist in water; or, ii. The original bulk of the oxygen may be
increased, in which case the oxygen must exist in the substance in
a greater proportion than it exists in water; or, iii. The original
bulk of the oxygen gas may be diminished; in which case the hydrogen
must predominate. Hence it is obvious, that, in the first of these
cases, the composition of a substance may be determined, by simply
ascertaining the quantity of carbonic acid gas yielded by a known
quantity of it; while, in the other two, the same can be readily
ascertained by means of the same data, and by noting the excess or
diminution of the original bulk of the oxygen gas employed.
The apparatus consists of two inverted glass syphons which act the
part of gasometers; these are connected when required, by a small
green glass tube, in which the substance is to be decomposed and
burnt: the syphons are very carefully gradated; so that the quantity
of gas in them can be accurately estimated; and are supplied with
cocks both above and below, so that they can be filled with mercury,
the mercury drawn off and gas introduced, the gas transferred through
the green glass tube, or the contents retained in an undisturbed
state, with the utmost readiness and ease. The substance to be
decomposed, may be put into a platina tray, and introduced alone
into the green glass tube, and being there heated by a spirit lamp,
be burnt in the gas passing over it; or it may be mixed with pure
siliceous sand; or, what is most generally preferable, be mixed with
peroxide of copper, which is always left, in consequence of the
excess of oxygen gas used, in the state in which it was introduced.
After the experiment the volume of gas is easily [p481] corrected
for pressure, and if necessary for temperature, and the carbonic acid
ascertained by the removal and analysis of a portion. No correction
is required for moisture, the gas always being used saturated with
water.
Dr. Prout considers the principal alimentary substances as reducible
to three great classes, the _saccharine_, the _oily_, and the
_albuminous_; and his paper relates to the first of these. This, with
certain exceptions, includes the substances in which, according to
MM. Gay Lussac and Thenard, the oxygen and hydrogen are in the same
proportion as in water. Such substances are principally derived from
the vegetable kingdom, and being at the same time _alimentary_, Dr.
Prout uses the terms _saccharine principle_ and _vegetable aliment_
as synonymous.
The following tables show some of Dr. Prout’s results with several
substances, extreme care having been taken in every case to obtain
the bodies pure, and new processes often resorted to for that purpose.
SUGAR.
Carbon. Water.
Pure sugar-candy 42.85 57.15
Impure sugar-candy 41.5 to 42.5 58.5 to 57.5
East India sugar-candy 41.9 58.1
English refined sugar 41.5 to 42.5 58.5 to 57.5
East India refined sugar 42.2 57.8
Maple sugar 42.1 57.9
Beet root sugar 42.1 57.9
East India moist sugar 40.88 59.12
Sugar of diabetic urine 36. to 40? 64. to 60?
Sugar of Narbonne honey 36.36 63.63
Sugar from starch 36.2 63.8
AMYLACEOUS PRINCIPLE.
Carbon. Water.
Fine wheat starch 37.5 62.5
" dried (i.) 42.8 57.2
" highly dried (ii.) 44 56
Arrow root 36.4 63.6
" dried (iii.) 42.8 57.2
" highly dried (iv.) 44.4 55.6
(i.) Dried between 200° and 212° for twenty hours, lost 12.5 per cent.
(ii.) Part of the former, dried between 300° and 350° for six hours,
lost 2.3 per cent.
(iii.) Dried as (i.), lost 15 percent.
(iv.) Part of the last, heated to 212° for six hours longer, lost 3.2
per cent. more.
LIGNIN, OR WOODY FIBRE,
Obtained by rasping wood, and then pulverising it in a mortar;
boiling the impalpable powder in water till nothing more was [p482]
removed, then in alcohol; again in water, and dried in the air till
they ceased to lose weight.
Carbon. Water.
From box 42.7 57.3
" dried (i.) 50. 50.
From willow 42.6 57.4
" dried (i.) 49.8 50.2
(i.) Dried at 212° for six hours, afterwards between 300° and 350°
for six hours. That from box lost 14.6, that from willow 14.4 per
cent.
Acetic acid 47.05 52.95
Sugar of milk 40. 60.
Manna sugar 38.7 61.3
Gum arabic 36.3 63.7
" dried (i.) 41.4 58.6
(i.) Dried between 200° and 212° for twenty hours, lost 12.4 per
cent. The same gum further heated to between 300° and 350° for six
hours, lost only 2.6 per cent., and had become deep brown.
Vegetable Acids. Carbon. Water. Oxygen.
Oxalic acid 19.04 42.85 38.11
Citric acid 34.28 42.85 22.87
Tartaric acid 32.00 36.00 32.00
Malic acid 40.68 45.76 13.56
Saclactic acid 33.33 44.44 22.22
29. _Preparation of Sulphate of Quinia and Kinic Acid, without the
use of Alcohol_.—The following is the process of MM. Henry and
Plisson: About two pounds of bark are to be coarsely powdered and
boiled with water, acidulated with sulphuric acid in the usual
manner. When the hot liquors are cleared, recently prepared and moist
hydrate of lead is to be added until the fluid is neutral, and has
acquired a faint yellow colour; this must be done carefully, lest too
much hydrate of lead be added. As the decoloration of the decoction
is necessary, the liquid, if it remains turbid until the next
morning, must have a little more hydrate added and be re-filtered,
but the operation is rarely subject to this inconvenience, being
usually finished in a few hours. The yellow liquid contains a little
kinate of lead, much kinate of lime, kinate of quinia or cinchonia,
a little colouring matter, and traces of other substances. The
washed deposite consists of colouring matter, combined with oxide of
lead, sulphate of lead, and a portion of free quinia; contains no
sub-kinate of lead.
The lead, dissolved in the fluid, is to be separated by a few drops
of sulphuric acid, or a small current of sulphuretted hydrogen, and
the filtered liquid is to be precipitated by adding caustic lime,
previously mixed into a thin paste with water, until the earth is
in very slight excess; in this manner the quinia is precipitated.
The addition of sulphuric acid readily converts this quinia into
sulphate, [p483] which may be obtained in very white and silky
crystals. The fluid left after the separation of the quinia,
contains a kinate of lime almost pure. Being evaporated until of
the consistence of syrup, it readily crystallizes in a mass, which
may then be purified by recrystallization. The kinate of lime may
be precipitated by means of alcohol, and then be crystallized after
solution in water or diluted alcohol; or, by adding oxalic acid drop
by drop, according to the directions of M. Vauquelin, the lime may
be separated and kinic acid obtained. Two thirds of the quinia or
cinchonia in a specimen of bark may be thus separated, and with such
facility as to offer a ready test of the presence of these alkalies
in any wood or bark submitted to examination.—_Ann. de Chimie_,
xxxv., 166.
30. _Pure Narcotine prepared_.—The following process is that
practised by Mr. Carpenter. Digest one ounce of coarsely powdered
opium in one pint of ether for ten days, frequently submitting it
to ebullition in a water bath; separate the ether and add fresh
portions until the opium is exhausted; place the ethereal solution in
a wide-mouthed bottle, and, covering the mouth with bibulous paper,
allow the ether to evaporate spontaneously, but slowly; as the fluid
diminishes, it leaves the sides of the bottle coated with crystals
of narcotine; as the solution becomes more dense, the crystals
enlarge and accumulate, and the bottom of the vessel is covered with
large transparent crystals, accompanied with a brown viscid liquor
and extract, which contains an acid resin, caoutchouc, &c. Separate
these substances and wash the crystals in successive portions of cold
ether to remove the extract; then dissolve them in warm ether, and
evaporate slowly as before; beautiful snow white crystals of pure
narcotine will be obtained: those on the sides of the vessel assume
plumose and arborescent forms; they enlarge as the solution becomes
more concentrated, and the bottom of the bottle becomes covered with
pure narcotine, assuming the rhomboidal prismatic form with some
modifications of maccled crystals. The crystals towards the bottom
are transparent, but the most minute at the top are opaque and snow
white. By picking out the largest and most regular crystals, again
dissolving and evaporating, and repeating the same process, each
time selecting the largest and best crystals, some were obtained the
eighth of an inch in diameter, and still larger might be produced by
similar operations.—_Silliman’s Jour._, xiii. 27.
31. _Uncertain Nature of Jalapia_.—Relative to Mr. Hume’s supposed
vegeto-alkali _Jalapia_, M. Pelletier says it is nothing more than
a mixture of sulphate of lime and sulphate of ammonia.—_Jour. de
Pharmacie_.
32. _Preparation of pure Mellitic Acid, by_ M. Wöhler.—Concentrated
solution of carbonate of ammonia was poured upon finely pulverised
mellite, and boiled until the excess of ammonia was [p484]
dissipated; the solution was filtered and left to crystallize. The
pure crystals, being dissolved in water, were precipitated by acetate
of lead, and the mellitate of lead, after being well washed was
decomposed by sulphuretted hydrogen; being filtered, the solution was
evaporated to dryness, during which the mellitic acid precipitated
as a white powder; being dissolved in cold alcohol, and left to
evaporate spontaneously, the acid was obtained in acicular crystals.
In this state it is very acid, unaltered by air, very soluble in
water and alcohol, and sustains a considerable heat without change;
it does not fuze, but ultimately sublimes, though probably not
without decomposition. When boiled for a considerable time with
alcohol, it undergoes a peculiar change, and occasions the production
of a new acid substance, resembling the benzoic acid.
33. _On a New Acid existing in Iceland Moss_.—The reddish purple
colour which is produced by adding a decoction of Iceland moss to
per-salts of iron, has been attributed to the presence of gallic
acid, but is found by M. Pfaff to be occasioned by a new acid body
which may be separated in the following manner. A pound of the
lichen cut small is to be macerated in solution of carbonate of
potassa, until all that is soluble is separated; the above quantity
will neutralize two gros[133] of the carbonate. The filtered
liquor is to be precipitated by acetate of lead, and the brown
precipitate produced, when well washed, is to be diffused through
water, and sulphuretted hydrogen passed through it until all the
lead is separated. The filtered liquor is acid, and by spontaneous
evaporation, yields dendritic crystals. The crystals, when heated,
carbonize, but produce no odour like that of tartaric acid, and lime
is left. If they be dissolved and acted upon by alkaline carbonates,
carbonate of lime is thrown down, and alkaline salts, containing the
new acid, are produced.
The potash salt crystallizes in quadrilateral prisms, needles
or plates, and is not deliquescent. The soda salt has similar
characters, and the ammonia salt crystallizes in needles. These salts
abundantly precipitate the acetate and muriate of iron of a red brown
colour; they precipitate sulphate and nitrate of zinc white; muriate
of manganese slightly of a clear brown colour; barytic and strontian
salts abundantly white; being mixed with strong solutions of muriate
or acetate of lime, they gradually produce an acicular crystalline
white precipitate; acetate of silver yields an abundant white
precipitate, which does not change colour in less than twenty-four
hours: they do not precipitate salts of glucina, magnesia, alumine,
uranium, nickel, copper, cobalt, gold or platina. This substance has
been named the lichenic acid, and is distinguished from boletic acid
by the different character of its vapour, and by forming an insoluble
salt with baryta.—_Bull. Univ._ A. viii. 270.
FOOTNOTE:
[133] About one hundred and twenty grains.
34. _Remarks on the Preparation of M. Gautier’s Ferro-prussiate
[p485] of Potash, as described in this Journal for_ July,
1827.[134]—It is stated in the above article, “numerous
investigations induced M. Gautier to conclude that when animal
matter is calcined alone, it yields but little cyanogen; that when
mixed with potash it gives more; that the _substitution of nitre_
for potash, and the addition of iron or scales of iron, augmented
the production of cyanogen and gave a ferro-prussiate. The following
is the process of manufacture to which M. Gautier has ultimately
arrived,” (for which see the Journal, 227.)
M. Gautier giving the proportions of materials, directs—
Blood in a dry state 3 parts
Nitre 1 "
Iron scales 1/50 of the blood employed.
Blood not being at hand, animal muscular fibre was substituted,
and the following results were obtained. I am not aware that the
dried parts of animal muscular fibre are more inflammable than the
coagulated and dried parts of blood:—
Muscular fibre 3 parts
Nitre 1 "
Iron filings 1/50 of the undried muscle employed.
The muscular fibre, nitre and iron filings were beat into a mass, and
partially dried by a moderate heat; they were then returned to the
mortar and reduced to a perfectly homogeneous greyish white powder.
This was dried and weighed, and appeared to be reduced to nearly
equal parts of nitrate of potash and animal fibre.
The desiccation having completed by a very moderate heat on a sand
bath, will not, as far as I am aware, differ materially from that
produced by exposing the mass in “an airy situation to dry,” as
nitrate of potash undergoes no decomposition by admixture with animal
matters at a low temperature.
When the desiccation was completed, the mixture was charged into an
iron cylinder, placed in the sand-bath, and though combustion was
not anticipated in this part of the process, yet the mouth of the
cylinder was turned towards the wall, lest an accident should occur,
(which appeared to me to be more than probable in some stage of the
process.) In about two hours after the cylinder had been heated, I
was surprised to see its contents ejected with considerable force,
in a state of brilliant combustion. Supposing something in the above
experiment had been overlooked, and that, if the materials had
been longer in contact previously to subjecting them to complete
desiccation, this inflammation would not have taken place, the
experiment was repeated with the following precautions: after the
muscular fibre had been subjected to the action of the pestle in
combination with the prescribed quantity of nitrate of potash, the
mass was boiled with water for some hours, and then gently evaporated
to dryness; even now, by applying a piece of red-hot charcoal, it was
found that the nitre was in a condition to enter [p486] into active
combustion, and if the cylinder had been again charged and subjected
to a temperature capable of producing ignition, there cannot be a
doubt, but that a similar inflammation would have taken place.
However this might be, this quantity of material was now mixed
with hydrate of potash to an equal weight with the nitre used; and
the mass subjected to the heat of a sand-bath for some hours, and
afterwards submitted to the action of a naked fire for rather more
than an hour, and the heat brought up to redness. No considerable
action took place, but some particles of the carbonaceous matter were
ejected, and produced brilliant scintillations in the fire, so that
we may conclude, notwithstanding the presence of so large a quantity
of potash, the properties of the nitre were not destroyed.
H. P.
_Canal-street, Birmingham_.
FOOTNOTE:
[134] Pages 207 and 208.
III. NATURAL HISTORY.
1. _Squalls of Wind on the African Shores_.—The following description
is by D. M. Milnegraden, from the relations of his father. “The
approach of the squall is generally foreboded by the appearance of
jet black clouds over the land, moving in a direction towards the
sea, at the same time that a gentle breeze blows towards the shore.
In these circumstances, the precaution which my father usually
adopted, was to take in immediately all sail, so as to leave the ship
under bare poles, and send the whole of the crew below decks. As the
tornado approaches nearer, the rain is observed to be gushing down
in torrents, and the lightning darting down from the clouds with
such profusion, as to resemble continued showers of electric matter.
When, however, the squall comes within the distance of about half a
mile from the ship, these electric appearances altogether cease; the
rain only continues in the same manner. As the tornado is passing
over the ship, a loud crackling noise is distinctly heard among
the rigging, occasioned by the electric matter streaming down the
masts, whose points serve to attract it, and I think that I have been
told, that when this phenomenon takes place at night, a glimmering
of light is observed over every part of the rigging. But when the
squall has removed to about half a mile beyond the ship, exactly
the same appearances return by which the squall was characterised
in coming off the shore, and before reaching the same distance from
the ship. The lightning is again seen to be descending in continued
sheets and in such abundance as even to resemble the torrents of rain
themselves which accompany the squall. These squalls take place every
day during a certain season of the year called the Harmatan season.
The jet black clouds begin to appear moving from the mountains about
nine in the morning, and reach the sea about two in the afternoon.
Another very singular fact attending these tornados is, that, after
they have moved out eight or nine leagues to sea, where [p487] they
become apparently expended, the lightning is seen to rise up from the
sea. The violence of the wind during the continuance of the storm is
excessive.”—_Jameson’s Journal_, 1823, p. 367.
2. _Destruction of an Oak by Lightning_.—M. Muncke describes a case
in which an oak, being struck by lightning, was rent and destroyed
in an extraordinary manner. The trunk of the tree was about fifteen
feet in height, a foot and a half or two feet in diameter at the
branches, and three feet in diameter at the root. The top of the
tree was separated as if by the stroke of a hatchet, and without
any appearance of carbonization: the trunk was torn into a thousand
pieces, exceedingly small in size when compared with the original
mass, and thrown to a great distance. The division and destruction
was such as to sustain the thought, that in certain cases the
lightning might cause the entire dispersion of the tree, an opinion
which was suggested by the circumstance that lightning which had
fallen at Le Chateau de Marbourg left no traces of a rafter that had
occurred in its course.—_Bull. Univ._ A. viii. 194.
3. _Description of a Meteoric Fire-Ball seen at New Haven by the Rev.
S. E. Dwight_.—The meteor appeared on Saturday evening, March 21,
1813, a little before ten o’clock. The sky was much overcast, but
the covering thin, and the stars were in full view towards the north
where the meteor appeared. Dr. Dwight was standing on a platform on
the north side of the house looking eastward, when the light first
broke upon him, and for a moment supposed it to be lightning, but was
instantly induced by its continuance to look at the luminary. The
following are the observations made at the time.
i. The meteor was at first about 35° above the horizon, and, judging
from the course of a fence near at hand, its direction about N. 20°.
E.
ii. Its figure nearly that of an ellipse, with the ends in a slight
degree sharpened or angular.
iii. The length of its transverse diameter appeared to be about equal
to the apparent diameter of the moon when on the meridian, and that
of the conjugate about three fourths of the transverse.
iv. The colour rather more yellow than that of the moon.
v. A tail of light, ten or twelve degrees in length, was formed
behind it; broadest near the body; decreasing in breadth very slowly
for about two-fifths of its length, after which it was uniform, and
about as wide as the apparent diameter of Venus. The direction of the
tail was coincident with that of the transverse diameter.
vi. The ball was far more luminous than the tail, and the part
connected with the tail scarcely less distinct than the opposite part.
vii. The light was such that all objects cast distinct shadows,
though less strongly marked than when the moon is full.
viii. Numerous sparks continually issued from the ball of the [p488]
meteor; they were of the apparent size, but much more brilliant
than the smaller stars, and after descending a little distance,
disappeared.
ix. The meteor was visible for about eight or perhaps ten seconds.
x. A second or two before its disappearance, three much larger
sparks or luminous fragments were thrown off at once, two of them
the apparent size of Venus, the third larger. These were the last
pieces which were seen to leave the body. Their paths were at first
nearly parallel with that of the meteor, yet beneath it. From this
direction, however, they all deviated constantly and rapidly, in
parabolic curves, until they seemed falling perpendicularly towards
the earth. Each fragment became less and less distinct until it
disappeared. The largest continued visible until about 20° from the
horizon.
xi. The meteor itself disappeared as suddenly as if, in one
indivisible moment, it had passed into a medium absolutely opaque,
or as if, at a given moment, it had left the atmosphere; but a few
moments afterwards there was a distinct and somewhat extensive
illumination over that part of the sky for about a second.
xii. When the meteor disappeared, it was about 30° above the horizon
in the direction of N. 45° E. or 25° east of the place where it was
first seen. The direction of the path was probably from W. by S. to
E. by N. The meteor was obviously going from the observer, its path
making an angle with the optic axis of about 60°.
xiii. Between eight and ten minutes after the disappearance of the
meteor, there was a loud and heavy report, accompanied by a very
sensible jar; it did not much resemble either thunder or the report
of a cannon, but was louder, shorter, and sharper than either, and
was followed by no perceptible echo.
xiv. A friend of Dr. Dwight’s, who was in Berlin at the time, about
twenty-three miles due N. of Newhaven, saw the meteor distinctly, but
made no particular observations. His account accorded generally with
that given; but the meteor appeared to him larger, more elevated, and
somewhat more to the east in its apparent place. No account could
be obtained of any fragments which had fallen from it.—_Silliman’s
Journal_, xiii. 35.
4. _Remarkable Meteoric Phenomenon, described by_ Chladni.—A noise,
resembling thunder in its rolling nature, was heard at Saarbruck
and the environs, about four o’clock on the 1st of April, 1826, the
atmosphere being clear, and the sun shining brightly. During the
sound, a greyish object, apparently about three feet and a half in
height, was seen in the air, rapidly approaching the earth, and there
expanding itself like a sheet; there was then silence for about a
minute, after which another sound, resembling thunder, was heard, as
if it had originated at the place where the meteor fell. Nothing was
found when the place was afterwards examined.—_Bull. Univ._ A. viii.
143. [p489]
5. _Aurora Borealis seen in the Day-time at Canonmills_.—The morning
of Sunday, September 9th, was rainy, with a light gale from the N.E.
Before mid-day the wind began to veer to the west, and the clouds
in the north-western horizon cleared away: the blue sky in that
quarter assumed the form of the segment of a very large circle,
with a well-defined line, the clouds above continuing dense, and
covering the rest of the heavens. The centre of the azure arch
gradually inclined more to the north, and reached an elevation of
nearly 20°. In a short time very thin fleecy clouds began to rise
from the horizon within the blue arch; and through these very faint
perpendicular streaks, of a sort of milky light, could be perceived
shooting; the eye being thus guided, could likewise detect the same
pale streaks passing over the intense azure arch, but they were
extremely slight and evanescent. Between nine and ten in the evening
of the same day, the aurora borealis was very brilliant: so that
there is no reason to doubt that the azure arch in the morning, and
the pale light seen shooting across it, were connected with the same
phenomenon.—_Jameson’s Jour._ 1827, p. 378.
6. _Aurora Borealis in Siberia_.—Baron Wrangle says, that in Siberia,
when shooting stars pass across the space occupied by polar lights,
fiery beams suddenly arise in the place traversed by the shooting
star: further, that when a polar beam rises high towards the zenith,
the full moon also being high, it gradually forms a luminous circle
around the moon, at a distance of 20° or 30° from her, remains in
this form for a short time, and then disappears.
7. _On the Presence of Ammonia in Argillaceous Minerals_.—Being
engaged in the examination of different specimens of gypsum, M. Bouis
observed, that traces of ammonia were evident in one containing
much argillaceous matter. The peculiar odour common to argillaceous
minerals when breathed upon, was very striking in this specimen of
gypsum; when a portion of it was moistened with solution of potash,
and muriatic acid brought near, white vapours were produced, and
reddened litmus paper was very quickly rendered of a blue colour in
its vicinity.
It was now suspected that all mineral substances, emitting an
argillaceous odour, contained ammonia; a great number of specimens
were tried, being moistened with solution of caustic potash, and
examined by litmus paper. In no case was ammonia absent, and with
common clay it continued to be evolved for more than two days.
Amongst the substances tried, were pipe clay, other clays, numerous
gypsums, Paris plaster, steatite, &c. The antiquity of the mineral
seemed to have no relation to the ammonia.
M. Bouis concludes that, in all cases, the argillaceous smell
of minerals is connected with, and dependent upon, the presence
of ammonia, the latter being the vehicle of this particular
odour.—_Annales de Chimie_, xxxv. 333. [p490]
8. _Composition of Apatite_.—According to M. Rose, the apatite from
the following localities gave the annexed proportions of chloride and
fluoride of calcium, the rest being phosphate of lime with occasional
traces of iron and magnesia:—
S. G. Chlo. Calc. Fluor. Calc.
Apatite from Suarum in Norway 3.174 4.280 4.590
Cabo de Gota in Spain 3.235 0.885 7.049
Arendal 3.194 0.801 7.010
Greiner in the Tyrol 3.175 0.150 7.690
Faldigl, ditto 3.166 0.100 7.620
St. Gothard 3.197 trace 7.690
Ehrenfriedersdorf 3.211 trace 7.690
_Annales de Chimie_.
9. _Burmese Petroleum Wells_.—“The gentlemen of the mission examined
carefully the celebrated Petroleum Wells, near which they remained
for eight days, owing to the accident of the steam-vessel taking the
ground in their vicinity. Some of the wells are from thirty-seven to
fifty-three fathoms in depth, and are said to yield at an average,
daily, from 130 to 185 gallons of the earth-oil. The wells are
scattered over an area of about sixteen square miles. The wells are
private property, the owners paying a tax of five per cent. of the
produce to the state. This commodity is almost universally used
by the Burmans as lamp oil. Its price on the spot does not, on an
average, exceed from fivepence to sevenpence halfpenny per cwt. The
other useful mineral or saline productions of the Burman empire are
coal, saltpetre, soda, and culinary salt. One of the lakes affording
the latter, which is within six or seven miles of the capital, was
examined by the gentlemen of the mission.” Crawford’s Mission to
Ava.—_Jameson’s Journal_, 1827, p. 366.
10. _Direction of the Branches of Trees_.—Professor Eaton remarks
that all trees with spreading branches accommodate the direction
of the lower branches to the surface of the earth over which they
extend, as may be seen in orchards growing on the sides of hills,
and in all open forests; and inquires what influence can the earth
have upon the branches on the upper side of a tree, which causes them
to form a different angle with the body of the tree from the angle
formed by the branches on the lower side, so that all the branches
hold a parallel direction to the earth’s surface.—_Silliman’s
Journal_, xiii. 194.
11. _Effects of Light on Vegetation_.—The following observations by
Professor Eaton are dated Rensselaer school, Troy, April 30, 1827.
“Clouds and rain have obscured the hemisphere during the last six
days. In that time the leaves of all the forests which are seen from
this place have greatly expanded. But they were all of a pallid hue
until this afternoon. Within the period of about six hours, they have
all changed their colour to a beautiful green. As the only efficient
change which has taken place, is that we have a [p491] serene sky,
and a bright sun, we may say with confidence that this change of
colour is produced by the action of the sun’s rays.”
“Seven years ago, next month, I had a still more favourable
opportunity to observe this phenomenon in company with the Hon. J.
Lansing, late Chancellor of this State. While we were engaged in
taking a geological survey of his manor of Blenheim, the leaves of
the forest had expanded to almost the common size in cloudy weather.
I believe the sun had scarcely shone upon them in twenty days.
Standing upon a hill, we observed that the dense forests upon the
opposite side of the Schoharie were almost white. The sun now began
to shine in full brightness. The colour of the forest absolutely
changed so fast that we could perceive its progress. By the middle of
the afternoon, the whole of these extensive forests, many miles in
length, presented their usual summer dress.”—_Silliman’s Journal_,
xiii. 193.
12. _Organization and Reproduction of the Trufle_.—The trufle,
according to the account given of it by M. Turpin, in a memoir read
to the Academy of Sciences, is a vegetable entirely destitute of
leafy appendages or of roots; it is nothing more than a rounded
subterraneous mass, absorbing nourishment upon every point of its
surface, and the reproduction of which is dependent upon bodies
generated within its substance. The trufle is composed of, i.
globular vesicles, destined, to the reproduction of the vegetable;
ii. short and barren filaments, called by M. Turpin, _tigellules_.
The whole forms a substance, at first white, but which becomes brown
by age, with the exception of particular white veins. This change of
colour is dependent upon the presence of the reproductive bodies or
_trufinelles_. Each globular vesicle is fitted to give birth, on its
internal surface, to a multitude of these reproductive bodies, but
there are only a few of them which perfect the young vegetable. These
dilate considerably, and produce internally other smaller vesicles,
of which, two, three, or four increase in size, become brown, are
beset with small points on their exterior surface, and fill the
interior of the larger vesicle. The small masses thus formed, are the
_trufinelles_, and become trufles after the death of their parent.
Thus the brown parts of the trufle are those which contain the
trufinelles, and the interposed white veins are the parts which are
destitute of trufinelles. The parent trufle, having accomplished its
growth and the formation of the reproductive bodies within, gradually
dissolves and supplies that aliment to the young vegetable which is
proper for them; the cavity originally occupied by it in the earth
is then left occupied by a multitude of young trufles, of which the
stronger starve or destroy the others, whilst they frequently adhere
together, and, enlarging in size, reproduce the phenomena already
described.
The reporters of this memoir to the Academy state that they have
verified M. Turpin’s account, but point out a circumstance in the
natural history of the trufle, which is still unexplained. If the
[p492] method described be the only mode in which the trufle
is reproduced, then it is difficult to comprehend the enormous
multiplication of that vegetable in certain parts of France, where
immense quantities are annually collected without exhausting or even
diminishing the race. If the plant has no means of progression, how
can the young trufles leave the place of their birth, and become
disseminated over the soil? The Mémoire received the approbation of
the Academy.—_Revue Ency._ xxxv. 794.
13. _Alteration of Corn in a subterraneous Repository_.—An inhabitant
of Deneuvre in the department of Merthe, whilst excavating in the
locality of the ancient citadel of that town, found a large quantity
of corn which appeared to have been carbonized. A portion was sent
to M. Braconnot for examination, but without any particulars of the
cavity containing it. The grain was smooth on the exterior, and
unchanged in form, but its aspect announced the entire destruction
of its proximate principles. It floated on water, could be crushed
between the finger to a black powder, and when rubbed on paper left
traces resembling those of black chalk.
Being analysed, it was found to consist principally of a substance
resembling ulmine in its properties, ulmate of lime and carbonaceous
matter: the proportions were
Ulmine 26.5
Ulmate of lime, containing some phosphate of lime
and a little oxide of iron 42.0
Carbonaceous matter 30.0
Muriates of potash and lime 1.5
Nitrates of potash and lime 1.5
Fatty matter of the consistency of wax, undetermined.
-----
100.0
Although the time during which this corn has been stored up is
probably very long, still M. Braconnot thinks the principal cause of
the change in it has been humidity; and thinks also that the same
may have been the case with the corn lately found in an Egyptian
tomb[135], and quotes the known fact of corn having been found at
Scarpone, an ancient Roman station, preserved in good condition,
during eighteen centuries, in a reservoir constructed of Roman mortar.
The best use that could be made of the carbonized corn of Deneuvre
was to apply it as a manure, for it contained the best elements of
a substance of this kind, and M. Braconnot had long since observed
the presence of ulmine in good manure, its acid properties, and its
effects on vegetation. He adds also that Bruyères earth of excellent
quality gave one-fourth of a combustible matter formed of ulmine
and a carbonaceous body but little soluble in potash, the remaining
three-fourths being a pure siliceous sand without a trace of lime.
Yet so effectual is this earth, that, where it cannot be obtained,
certain exotics cannot be cultivated.—_Annales de Chimie_, xxxv. 262.
[p493]
FOOTNOTE:
[135] See p. 210 of the last Number.
14. _Quick Method of putting Insects to Death_.—The following method
is by M. Ricord, for the use of naturalists. The insect is to be
fixed on a piece of cork and put under a jar or vessel with a little
ether; the latter being placed either in a capsule, or on the plate
on which the jar or glass is placed: the vessel should apply closely,
that the vapour of the ether may be retained, and the air within be
prevented from changing its place. The insect thus immersed in the
ethereal atmosphere will soon die without having time to hurt its
form or appearance by violence.—_Bull. Univ._ B. xii. 295.
15. _Destruction of Snails by common Salt_.—M. Em. Rousseau had
applied common salt as a manure to a small piece of garden, and
remarked that where snails had come in contact with the salt they
quickly died. Wishing to confirm the fact, he strewed some salt upon
the ground and placed a number of snails amongst it; all those which
came out of their shells and touched the salt immediately threw out a
greenish globular froth, and in a few minutes were dead. The fact may
be turned to account by agriculturists and gardeners.—_Bull. Univ._
D. viii. 276.
16. _Remarkable Hairy Man_.—The following account is given of an
individual of this kind in Crawford’s Mission to Ava. “As connected
with this department may be mentioned the existence at Ava of a
man covered from head to foot with hair, whose history is not less
remarkable than that of the celebrated porcupine man who excited so
much curiosity in England and other parts of Europe near a century
ago. The hair on the face of this singular being, the ears included,
is shaggy, and about eight inches long. On the breast and shoulders
it is from four to five. It is singular that the teeth of this
individual are defective in number, the molares or grinders being
entirely wanting. This person is a native of the Shan country, or
Lao, and from the banks of the upper portion of the Saluen, or
Martaban river; he was presented to the king of Ava as a curiosity,
by the prince of that country. At Ava he married a Burmese woman,
by whom he has two daughters; the eldest resembles her mother, the
youngest is covered with hair like her father, only that it is white
or fair, whereas his is now brown or black, having, however, been
fair when a child, like that of the infant. With the exceptions
mentioned, both the father and his child are perfectly well-formed,
and, indeed, for the Burman race, rather handsome. The whole family
were sent by the king to the residence of the Mission, where drawings
and descriptions of them were taken.”—_Jameson’s Jour._ 1827, p. 368.
17. _Application of Remedies by Absorption from the Surface_.—The
following are the results obtained by M. Bailly, who has been
assiduously engaged in trying this plan.
_Salts of Morphia_, applied in this manner, speedily exhibit their
[p494] action upon the brain and nervous system, by the contraction
of the pupils, and often by dysuria and ischuria; nausea and vomiting
are rare; sometimes a sensation of itching is felt in the nasal
cavities, and papular eruptions not unfrequently appear upon the skin.
_Extract of Belladonna_, applied upon the upper surface of the feet,
produced all the consequences derived from its internal exhibition;
such as dilatation of the pupil and impaired vision.
_Extract of Squill_, while it augments transpiration, promotes the
urinary secretion, and facilitates expectoration.
_Well powdered Strychnine_ supports the suppuration of wounds
tolerably well, and stimulates the locomotive system without
inconveniently exciting the brain. It happens also in certain
palsies, such as those which are caused by the carbonate of lead,
that the power of motion is restored without the production of those
violent shocks which have been so unpleasant to patients. M. Bailly
has observed, with respect to this medicine in general, that it often
excites a marked turgescence about the head, heightening the colour
of the face, which demands the suspension of the remedy, if not the
intervention of blood-letting.
_Perchloride of Mercury_ (corrosive sublimate) produces an intense
sensation of heat, and corrodes the parts with which it comes in
contact. Sometimes, however, it has been known to relieve the pains
of exostoses, &c. _The proto-chloride_ (calomel) also excites pain,
particularly if rubbed upon a recently blistered surface. In this way
it may cure old syphilitic affections; but as a set-off against these
advantages, there is sometimes a difficulty in keeping up the action,
as the absorbent powers of the surface wear out by long continued
contact.
One great advantage of the _endermic_ practice is the exemption of
the digestive organs from an inconvenient or unaccustomed stimulus;
and its importance must be apparent where the stomach is incapable of
retaining medicines, or the power of deglutition is lost.—_Nouv. Bib.
Med._—_Med. Rep._ v. 341.
18. _On the Strix Cunicularia, or Coquimbo Owl_.—Captain Head, and
every reader of his “Rough Notes,” will, we are sure thank us for
any hint tending to throw light on facts related in that spirited
and interesting narrative; particularly as, in the course of his
adventures, circumstances are occasionally recorded somewhat
startling to those who are in the habit of considering whatever
surpasses their ken or comprehension as a travellers’ tale. Thus the
concluding part of the following passage, however true to the very
letter, as we shall show, has we know excited considerable surprise,
and possibly considerable doubt as to its accuracy.
“The Biscacho[136] is found all over the plains of the Pampas;
like rabbits they live in holes, which are in groups in every
[p495] direction, and which make galloping over these plains very
dangerous. These animals are never seen in the day, but as soon as
the lower limb of the sun reaches the horizon, they are seen issuing
from their holes in all directions, which are scattered in groups
like little villages, all over the Pampas. The biscachos, when full
grown, are nearly as large as badgers, but their head resembles a
rabbit, excepting that they have large bushy whiskers. In the evening
they sit outside their holes, and they all appear to be moralising.
They are the most serious looking animals I ever saw; and even the
young ones are grey headed, have mustachios, and look thoughtful and
grave. _In the day time their holes are always guarded by two little
owls, who are never an instant away from their post. As one gallops
by these owls, they always stand looking at the stranger and then at
each other, moving their old-fashioned heads in a manner which is
quite ridiculous, until one rushes by them, when fear gets the better
of their dignified looks, and they both run into the biscachos’
“hole_.”—(Head’s Rough Notes, p. 82.)
Captain Head has not given us the name of this owl, but in all
probability it was the Strix Cunicularia, or Coquimbo Owl, which is
described as flying _in pairs_, sometimes by day, and making its nest
_in long subterraneous burrows_[137]. In the singular motion of its
head, it however corresponds with the Strix Brasiliana, or Brownish
Horned Owl, mentioned by Maregrave in his History of Brazil, which he
says is easily tamed, and can so _turn about its neck_ that the tip
of the beak shall exactly point at the middle of the back; that it
also plays with men like an ape, _making many mowes_, (as Willoughby
translates it,) _and antic mimical faces_, and snapping with its
bill. But for the best account we have met with, we are indebted to
the splendid continuation of Wilson’s American Ornithology by Lucien
Bonaparte, under the title “Burrowing Owl—a bird,” he says, “that so
far from seeking refuge in the ruined habitations of man, fixes his
residence within the earth; instead of concealing itself in solitary
recesses of the forests, delights to dwell on open plains, in company
with animals remarkable for their social disposition, neatness, and
order. Instead of sailing heavily forth in the obscurity of the
evening or morning twilight, and then retreating to its secluded
abode, this bird enjoys the broadest glare of the noon-day sun,
and flying rapidly along, searches for food or pleasure during the
cheerful light of the day. In the trans-Mississippian territories
of the United States, this very singular bird _resides exclusively
in the villages of the Marmot, or Prairie Dog_, whose excavations
are so commodious, as to render it unnecessary that it should dig
for itself, as it is said to do in other parts of the world, where
no burrowing animals exist. These villages are very numerous, and
variable in their extent, sometimes covering only a few acres, and at
others spreading over the surface of the country for miles together.
They are composed of slightly [p496] elevated mounds, about two
feet in width at the base, and seldom exceeding eighteen inches in
height. In all these Prairie dog villages, the burrowing owl is seen
moving briskly about, or else in small flocks scattered among the
mounds, and at a distance it may be mistaken for the marmot itself
when sitting erect. They manifest _but little timidity, and allow
themselves to be approached sufficiently close for shooting_; but if
alarmed, some or all of them soar away, and settle down again at a
short distance: if further disturbed, their flight is continued until
they are no longer in view, _or they descend into their dwellings,
whence they are difficult to dislodge_. The burrows into which these
owls have been seen to descend on the plains of the river Platte,
where they are the most numerous, were evidently excavated by the
marmot, whence it has been interred by the learned and indefatigable
Say[138], that they were either common, though unfriendly residents
of the same habitation, or that the owl was the sole occupant by
right of conquest.” We have in the statements of Captain Head,
however, a proof that both tenants habitually resort at the same time
to one burrow; and we are assured by Pike and others, that a common
danger often drives them into the same excavation where lizards and
rattlesnakes also enter for concealment and safety.
In the above extracts we have noted in italics the striking
similarity to the account given by Captain Head.
E. S.
FOOTNOTES:
[136] This animal is probably either the Cavia Paca, Spotted Cavy,
or Arctomys Monax, Ferruginous Brown Marmot, though the latter is
described as principally found in North America.
[137] Turton, Lin. vol. i. 169.
[138] We have had no opportunity of consulting Say, and therefore
can only refer our readers to an author who has collected an
interesting store of facts relative to natural science, and
particularly with regard to this bird.
19. _Naturalisation of Fish_.—We have received the following from Mr.
Arnold of Guernsey.
Sir, 16th _August_, 1827.
Having understood that the correctness of Dr. Mac Culloch’s
statements respecting my pond, and the attempts to propagate sea fish
in it, have been questioned, I beg to say that his statements are
perfectly correct; and to add further, that during nearly four months
of the year the water is perfectly fresh, and is drunk by cattle.
In summer, the saltness varies; but no examination yet made has
discovered in it more than half as much salt as is contained in the
neighbouring sea-water.
I further beg leave to add, that the general size of the pond in
summer is about four acres and a half; in winter, when swelled by the
rains, it is extended to upwards of fifteen acres; which will account
for the freshness of the water.
I remain, Sir, your obedient humble servant,
_To the Editor of the Quarterly Journal_. J. B. ARNOLD.
20. _Mode of keeping Apples_.—It seems not to be generally known,
that apples may be kept the whole year round by being [p497]
immersed in corn, which receives no injury from their contact. If
the American apples were packed among grain, they would arrive here
in much finer condition. In Portugal it is customary to have a small
ledge in every apartment, (immediately under the cornice,) barely
wide enough to hold an apple: in this way the ceilings are fringed
with fruit, which are not easily got at without a ladder; while
one glance of the eye serves to shew if any depredations have been
committed.
21. _On the Cultivation and Forcing Sea Kale_.—The Crambe maritima,
or Sea Kale, is an indigenous plant of this and other countries of
Europe, and found on the sandy beach of the sea-shore.
It has been long introduced into our gardens as a culinary vegetable,
but it is only within the last thirty years, that it has been brought
into general use, and subjected to a mode of cultivation, very
different from that which was first bestowed upon it.
The principal value of this plant is its property of early growth;
appearing at table at a time when few such things can be had. It
precedes asparagus, for which it is no bad substitute; and as it
makes a dish of itself, it gives a variety to the delicacies of the
table; and if the opinions given of its medicinal virtues be correct,
it is well worth cultivation, and the notice we are about to take of
it, in describing an easy method of having it in great perfection
throughout the winter months, and up to the time it may be gathered
from the natural ground.
Prepare one or more beds (with alleys two feet wide between) for the
reception of the seeds, in the following manner: mark out the bed or
beds two and a half feet wide, and of any required length, as near
as can be from east to west; line off the sides and ends, driving a
stake at each corner to ascertain the boundaries; dig out the earth
of the bed one spade deep, removing it to some distance; fill this
excavation with the purest and finest sand which can be procured in
the neighbourhood, either from the sea-shore, the bed of a river, or
from a pit. It signifies nothing of what colour it is, so it be pure,
and as free from loam as it can be had; for in proportion as the soil
of the bed is poor or rich, so will the flavour of the plant be when
dressed. When this precaution is not taken, and when the plants are
suffered to enjoy the rich and cultivated soil of a kitchen garden,
or the situation made so, by rich dressings or coverings of fresh
manure, the plants are stimulated into an unnatural luxuriance, which
deteriorates the flavour, imparting to them that strong disagreeable
scent and taste, resembling common cabbage, than which nothing can
be a greater drawback on the value of the vegetable; but when grown
entirely in pure sand, the flavour is mild and pleasant, and is
relished by most palates.
When the bed is filled with sand and raised therewith about six
inches above the natural level of the ground, (and this should be
done previous to the end of March, which is the sowing season,) draw
a drill along the middle, from end to end, about three inches [p498]
deep, in which drop the seeds pretty thickly, as they can be thinned
out to the proper distance after they come up. If the sand or weather
be dry at the time of sowing, give a little water in the drill and
immediately cover up. If the seed be good, the plants will soon
appear, and when they are advanced to a size large enough to enable
the gardener to choose the most promising, let them be thinned out
to the distance of six or seven inches, the distance at which they
may remain. During the summer, the bed should be occasionally watered
with _dung water_; and this for the purpose of encouraging the growth
of the plants on their first setting off; and as manure given in
this shape is more fugitive than when applied in a more solid or
concentrated state, it cannot impart rankness to the plants when they
arrive at that age fit to be brought to table.
The plants cannot be forced, nor should any of their shoots be cut,
the first winter after sowing; but should be suffered and assisted to
establish themselves, and gain sufficient strength to yield adequate
crops, in the succeeding years.
About the month of November in the second winter after sowing, a
part at one end of the bed should be prepared for forcing. For this
purpose, and in order that it may be done with facility and effect,
a rough wooden frame or frames should be made, eighteen inches high
behind, and one foot high in front, shaped like a common hot-bed
frame, and of any convenient and portable length; and in width, the
same as the bed. Light wooden covers in convenient lengths should
be fixed by hinges to the back; these may be raised at will for
admission of light and air, and, in fine weather, may be thrown
entirely back. When the frames are placed, dig out the alleys one
foot deep to receive linings of hot dung, which may be banked op
against both the back and front of the frame. The surface of the bed
within the frame must be covered with soft, short straw, or hay, nine
inches thick, to arrest the heat which rises from the linings, and
form that warm humid region into which the shoots will advance. The
temperature of these dark frames must be regulated by due attendance;
and in intensely cold or frosty weather, the frames at night will
require coverings of mats and litter, to prevent the plants receiving
a check.
The required supply of the family—the time for it—and the length or
number of the frames, must be judged of by the gardener, and who will
act accordingly; but two frames are indispensable; because the second
should be considerably advanced by the time the crop in the first is
all cut.
Young plants may be transplanted; and if they are to be had, may
be tried; but the safer way is to sow and plant both, to prevent
disappointment; and in order that the roots be not too much exhausted
by forcing, one bed should be forced in one year, and another the
next.
The crowns of the roots have a tendency to rise; and as annual [p499]
additions of sand will be required after the autumnal dressing, the
beds by these additions become unsightly; but cutting off the most
aspiring (with its flowering stem) every summer, will keep the whole
within proper bounds. Instead of covering with dung or litter, to
protect from winter’s frost, the frames may be set on those parts
intended to be forced, to answer that purpose; and the uncovered
parts of the beds may receive a coat of mould out of the alleys, to
be drawn back off the sand in the spring.
The writer of this began to force Sea Kale as long ago as 1798, using
hot dung within, as well as without, a frame with glazed lights; but
soon found that, neither the glass nor dung _inside_ was necessary or
suitable; he, therefore, afterwards succeeded, by the above plan, to
produce the finest crops of this vegetable, at any time in the winter
months; and can confidently recommend such management, especially to
those who have no hot-house or hot-bed frames; because when there is
any early forced house or frames, if old roots are properly selected
and potted in the autumn, and placed in such house or frame, where
there is sufficient heat, and well shut up from light by whelming
other empty pots over them, a crop may be had in this way, without
the trouble and expense of out-door forcing.
J. M.
[p500]
METEOROLOGICAL DIARY for the Months of September, October, and
November, 1827, kept at EARL SPENCER’s Seat at Althorp, in
Northamptonshire.
The Thermometer hangs in a North-eastern Aspect, about five feet
from the ground, and a foot from the wall.
+--------------------------------------------------------------------+
| FOR SEPTEMBER, 1827. |
+----------------+-------------------+---------------+---------------+
| | Thermometer. | Barometer. | Wind. |
| +---------+---------+-------+-------+-------+-------+
| | Lowest. | Highest | Morn. | Eve. | Morn. | Eve. |
+-----------+----+---------+---------+-------+-------+-------+-------+
| Saturday | 1 | 37 | 60 | 30.20 | 30.20 | E | EbS |
| Sunday | 2 | 42 | 64 | 30.20 | 30.18 | NE | NE |
| Monday | 3 | 44 | 64 | 30.18 | 30.18 | NE | NE |
| Tuesday | 4 | 51 | 59 | 30.18 | 30.18 | NE | NE |
| Wednesday | 5 | 51 | 61 | 30.17 | 30.17 | NE | NE |
| Thursday | 6 | 48 | 57 | 30.17 | 30.17 | NE | NE |
| Friday | 7 | 51 | 59-1/2 | 30.17 | 30.15 | NE | NE |
| Saturday | 8 | 52 | 60 | 30.11 | 30.07 | NE | EbS |
| Sunday | 9 | 51 | 62 | 29.83 | 29.77 | EbS | SW |
| Monday | 10 | 55 | 67 | 29.74 | 29.69 | SW | SW |
| Tuesday | 11 | 55 | 69-1/2 | 29.66 | 29.58 | SSE | SbW |
| Wednesday | 12 | 55 | 62-1/2 | 29.54 | 29.57 | SW | W |
| Thursday | 13 | 50 | 61 | 29.70 | 29.93 | W | W |
| Friday | 14 | 46 | 65 | 30.03 | 30.03 | W | W |
| Saturday | 15 | 50 | 67 | 30.10 | 30.13 | W | WNW |
| Sunday | 16 | 58 | 67 | 30.17 | 30.17 | WbN | W |
| Monday | 17 | 57 | 66 | 30.17 | 30.16 | E | ENE |
| Tuesday | 18 | 57 | 62 | 30.13 | 30.10 | ENE | NE |
| Wednesday | 19 | 45 | 57 | 30.02 | 30.02 | SW | W |
| Thursday | 20 | 46 | 54 | 29.69 | 29.70 | SE | NE |
| Friday | 21 | 43 | 63 | 29.70 | 29.48 | NNE | SW |
| Saturday | 22 | 45 | 60 | 29.44 | 29.34 | SW | WbS |
| Sunday | 23 | 43 | 59 | 29.30 | 29.40 | SW | WSW |
| Monday | 24 | 40 | 60 | 29.50 | 29.50 | SE | SW |
| Tuesday | 25 | 42 | 61 | 29.50 | 29.50 | SSW | S |
| Wednesday | 26 | 48 | 65 | 29.48 | 29.48 | SE | S |
| Thursday | 27 | 52 | 66 | 29.48 | 29.57 | NE | NE |
| Friday | 28 | 48 | 64 | 29.57 | 29.57 | NE | SE |
| Saturday | 29 | 47 | 61 | 29.57 | 29.54 | E | SE |
| Sunday | 30 | 53 | 63 | 29.60 | 29.60 | SE | SE |
+-----------+----+---------+---------+-------+-------+-------+-------+
+--------------------------------------------------------------------+
| FOR OCTOBER, 1827. |
+----------------+-------------------+---------------+---------------+
| | Thermometer. | Barometer. | Wind. |
| +---------+---------+-------+-------+-------+-------+
| | Lowest. | Highest | Morn. | Eve. | Morn. | Eve. |
+-----------+----+---------+---------+-------+-------+-------+-------+
| Monday | 1 | 52 | 65 | 29.67 | 29.70 | SE | SE |
| Tuesday | 2 | 54 | 63 | 29.74 | 29.90 | E | ENE |
| Wednesday | 3 | 46 | 62-1/2 | 30.04 | 30.12 | ENE | ENE |
| Thursday | 4 | 45 | 60 | 30.21 | 30.23 | NE | NNE |
| Friday | 5 | 42 | 62 | 30.28 | 30.17 | NNE | NNE |
| Saturday | 6 | 44 | 61-1/2 | 30.10 | 29.96 | E | E |
| Sunday | 7 | 43 | 58 | 29.87 | 29.73 | E | SbE |
| Monday | 8 | 39 | 61 | 29.60 | 29.33 | SE | SE |
| Tuesday | 9 | 46 | 62 | 29.20 | 29.08 | SE | WSW |
| Wednesday | 10 | 48 | 53 | 29.20 | 29.13 | SW | NE |
| Thursday | 11 | 46 | 56 | 29.04 | 29.08 | SW | SW |
| Friday | 12 | 44 | 55 | 29.12 | 29.32 | W | W |
| Saturday | 13 | 34-1/2 | 53 | 29.39 | 29.39 | W | W |
| Sunday | 14 | 44 | 57 | 29.60 | 29.68 | W | SW |
| Monday | 15 | 46 | 61 | 29.70 | 29.71 | SW | SSW |
| Tuesday | 16 | 57 | 64 | 29.71 | 29.71 | SW | SSW |
| Wednesday | 17 | 49 | 62 | 29.71 | 29.69 | SE | SE |
| Thursday | 18 | 38 | 61 | 29.69 | 29.63 | SE | E |
| Friday | 19 | 45 | 60 | 29.63 | 29.63 | ENE | E |
| Saturday | 20 | 52 | 62 | 29.63 | 29.59 | E | E |
| Sunday | 21 | 50 | 59 | 29.50 | 29.42 | E | E |
| Monday | 22 | 52 | 59 | 29.28 | 29.10 | EbS | SE |
| Tuesday | 23 | 51 | 59 | 29.02 | 29.18 | SE | SE |
| Wednesday | 24 | 47 | 60 | 29.44 | 29.74 | SE | WbS |
| Thursday | 25 | 46 | 59 | 29.87 | 29.88 | WbS | SSW |
| Friday | 26 | 52 | 61 | 29.96 | 29.84 | SW | SE |
| Saturday | 27 | 46 | 60 | 29.63 | 29.46 | SE | SSW |
| Sunday | 28 | 45 | 57 | 29.31 | 29.50 | NE | NE |
| Monday | 29 | 33 | 48 | 29.77 | 29.88 | NE | WNW |
| Tuesday | 30 | 33 | 52 | 29.82 | 29.68 | W | W |
| Wednesday | 31 | 46 | 53 | 29.64 | 29.64 | NW | NNW |
+-----------+----+---------+---------+-------+-------+-------+-------+
+--------------------------------------------------------------------+
| FOR NOVEMBER, 1827. |
+----------------+-------------------+---------------+---------------+
| | Thermometer. | Barometer. | Wind. |
| +---------+---------+-------+-------+-------+-------+
| | Lowest. | Highest | Morn. | Eve. | Morn. | Eve. |
+-----------+----+---------+---------+-------+-------+-------+-------+
| Thursday | 1 | 32 | 50 | 29.87 | 29.90 | NW | NW |
| Friday | 2 | 37 | 51 | 29.68 | 29.90 | W | NNW |
| Saturday | 3 | 30 | 53 | 29.98 | 29.98 | W | W |
| Sunday | 4 | 41 | 56 | 30.00 | 30.03 | W | W |
| Monday | 5 | 44 | 56 | 30.10 | 30.20 | W | W |
| Tuesday | 6 | 45 | 57-1/2 | 30.18 | 30.11 | W | W |
| Wednesday | 7 | 45 | 48 | 30.06 | 30.03 | W | W |
| Thursday | 8 | 43 | 49 | 30.00 | 29.96 | E | E |
| Friday | 9 | 44 | 53 | 29.77 | 29.68 | W | WbN |
| Saturday | 10 | 46 | 54 | 29.73 | 29.80 | WbN | W |
| Sunday | 11 | 47 | 57 | 29.80 | 29.80 | W | NW |
| Monday | 12 | 35 | 53 | 29.97 | 30.00 | NW | WbN |
| Tuesday | 13 | 40 | 60 | 30.00 | 30.02 | WbN | WbN |
| Wednesday | 14 | 50 | 50 | 29.98 | 29.88 | EbS | SE |
| Thursday | 15 | 41 | 48 | 29.66 | 29.50 | SW | SE |
| Friday | 16 | 37 | 47-1/2 | 29.30 | 29.39 | E | ESE |
| Saturday | 17 | 30 | 47 | 29.62 | 29.69 | ESE | SE |
| Sunday | 18 | 36 | 51 | 29.86 | 29.95 | E | E |
| Monday | 19 | 45 | 50 | 30.02 | 30.02 | EbS | S |
| Tuesday | 20 | 45 | 48 | 30.00 | 29.92 | W | NW |
| Wednesday | 21 | 36 | 39 | 30.01 | 30.01 | NbW | N |
| Thursday | 22 | 31 | 34 | 29.80 | 29.60 | W | W |
| Friday | 23 | 17 | 36 | 29.58 | 29.47 | W | W |
| Saturday | 24 | 22 | 33 | 29.60 | 29.79 | WbN | WbN |
| Sunday | 25 | 21 | 39 | 29.79 | 29.80 | W | W |
| Monday | 26 | 37 | 45 | 30.08 | 30.12 | WNW | NW |
| Tuesday | 27 | 38 | 47 | 30.17 | 30.10 | SW | SW |
| Wednesday | 28 | 36 | 45 | 29.88 | 29.70 | S | SE |
| Thursday | 29 | 39 | 49 | 29.27 | 29.30 | SE | WbS |
| Friday | 30 | 35 | 51 | 29.30 | 29.30 | W | W |
+-----------+----+---------+---------+-------+-------+-------+-------+
[p501]
INDEX.
Abernethy, Mr., 337
Aberration, of glass and of diamond lenses, compared, 20
Absorption from the surface, remedies thus applied, 493
Abydus near Thebes, excavations by Mr. W. Banks at, 182
Acid, on a new vegetable, 217
Acon, Mr., James, on the growth of early and late grapes, 159
Adamant, difficulty of making lenses of, 16
Adams, Mr., his account of the Aurora Borealis seen in London, 398
Africa, season of malaria and fevers, 41
African travellers, hint respecting, 55
Agens Physiques, leur Influence sur la Vie, par W. F. Edwards, D.M.,
137, 296
Agnano, Lake, 45
Air, night, why avoided, 43
Air, on the determination of the mean temperature of the, 223
Alimentary substances, on, by Dr. Prout, 480
Alkaline springs of the West Riding of Yorkshire; their presumed
virtues, 25
Altheine, a new vegetable principle; discovered by M. Bacon, 217
Aluminum, preparation of, 474
Americans, North, possess swift merchant vessels, 32
Amici’s microscopes, Professor, 198
Ammonia, its presence in argillaceous minerals, 489
Amphitheatres, Roman, 366
Anatomy of animals, the comparative by C. J. Carus, M.D., 377
Ancient substances, chemical researches relative to certain, 209
Animal economy, conversations on the, 382
― fossil, generally found at Roman stations, 368
― known to the Romans, 369
Apatite, composition of, 490
Apothecaries, Society of, incorporated, 338
Apothecary, dissertation on the word, 337
Apples, kept well in corn, 496
Arago’s, Mr., experiment on the refractive power of bodies, 444
Architecture, naval, its theory, 26
Architecture, on the modern ornaments of, 292
Armies destroyed by the influence of malaria, 54
Arnold, Mr. J. R., respecting the naturalisation of fish, 496
Arsenic, its separation from nickel or cobalt, 209
― sulphuret of, 476
Astronomical and nautical collections, 113 _et seq._ 428
Average duration of human life in various countries, 58
Audition, experiments on, 67
Augustus Cæsar, Egyptian tablets relating to his victory, 314
Aurora Australis, described by Mr. Forster, 408
Aurora Borealis, seen in London, its description, by Mr. Kendall, 385
― ―, general description of this phenomenon, 405
― ― seen in the day-time at Cannonmills, 489
― ― in Siberia, 489
Aurora, Guido’s; critical examination of the composition, 11
Bacon, Anthony, Esq., stoves employed in his garden, 174
Banks, Mr. William, his discovery of the list of monarchs in
hieroglyphics, 182
Bark-beds, Mr. Bregazzi’s thermometer for, 425
Barometrical observations reduced to a standard temperature; by S.
Foggo, 458
Barrowby, Dr., anecdote of, 345
Basse, the, a voracious enemy of other fish, 325
Bellani, M., his reclamations of chemical discoveries, 469–470
Berthier, M., on porcelain, 478
Berzelius, M., 471
―, his canons, 64
Beurré d’Aremberg Pear, described, 173
Bichat’s treatise on asphyxy, 141
Biot, M., pendulum apparatus employed by him, 155
Birds, subjected to experimental inquiry, 299
Bismuth, property of, 202
―, its separation from mercury, by potassium, 476
Bisulphuret of copper, volcanic, 226
Bitter principle from aloes, on the, 214
Bitter substance produced by the action of nitric acid on indigo,
silk, and aloes, 210
Blair, Dr. Patrick, his history, 344
Bleeding, practice of, height to which it was carried in France, 331
Blight in fruit-trees prevented by painting a garden wall, 169
Blowpipe, treatise on the use of the, by John Griffin, 380
Bond, Thomas, Esq., on the cultivation of strawberries, 168
Botanic garden at Chelsea, 337
Bouvart, M., humorous anecdote, 330
Branches of trees, their direction, 490
Bromine, M., A de la Rive on, 465
―, its elementary nature ascertained, 466
―, prepared for sale by M. Balard, its discoverer, 466
Browne’s, Mr., articles in the _Ed. Rev._ relative to the
hieroglyphics, 317
Bruckman, Mr., his employment of the plough in excavations, 197
Brunel, Mr., his carbonic acid engine, 65
Bull, Marcus, on fuel, 378
Burckhardt, I. L., travels in Nubia, 189
Burnett, Mr. Gilbert, 76
Burton, Mr., his discovery of a triple inscription in Egypt, 92
Butler Dr., William, his tobacco practice, 339
― ― ―, anecdotes of, 342
Caledonia, the proportions of this ship, 33
Camaldoli, convent of, 45
Camellias, on the cultivation of, 172
Cantharides, preservation of, 231
Carbazotate of ammonia, 212
― of baryta, 213
― of copper, 213
― of lime, 213
― of magnesia, 213
― of potash, 212
― of silver, 213
― of soda, 212
Cardoon, on the varieties of, by Mr. A. Mathews, 162
Carlini, professor, his pendulum experiments on Mont Cenis, 153
Case, Dr. John, 330
Cattle, subject to intermittents and epidemics, 59
Celery, on the transplanting of, 168
―, upon the culture of, by T. A. Knight, Esq., 166
Cementation of iron by cast iron, 207
Champollion Figeac, M., 185
Champollion, M., his interpretation of hieroglyphics, 185, 315
_Chemical Manipulation_, by Michael Faraday, F.R.S., 221, 275
Chemistry, elements of, by Dr. Edward Turner, 60
Cherry, Chinese, [Prunus Pseudocerasus], described by T. A. Knight,
Esq., 173
Chevalier, MM. Vincent, their aplanatic object-glasses for diverging
rays, 248;
their microscopes, 257
Chinese language, Baron Von Humboldt’s letter on the genius of the,
92
Chloride of lime applied in cases of burns, 231
Chlorine, on its existence in the native black oxide of manganese,
by John M’Mullen, Esq., 258
Chromate, new double, by Mr. Stokes, 477
Chronology, the Bible, compared with that of the hieroglyphics, 185
― of Manetho, the, 180
Chrysanthemums, 426
Circle of the seasons, and perpetual key to the calendar and
almanack, 381
Cities of Great Britain compared with those of other European
nations, 285
Cleopatra of Egypt, tablet containing her name, 313
Cline, Henry, epitaph for the eminent surgeon, 333
Clock, improved, made by F. Houriet, of Loch, 454
Cobalt, deuto-sulphuret of, 476
Cobbett’s English Grammar, 96
Cochrane’s, Captain C. S., Journal in Colombia, 356
Cocoa palm, the, 262
Coins, British, having the tapir and elephant on them, 358–361
Columbium, a metal discovered by Mr. Hatchett, 277
Combination of numerous bodies effected by the use of feeble
electric currents, 462
Comet, Ephemeris of the periodical, for its return in 1828, 428
Commerce of the Romans with India, 361
Complexions, sallow, in countries subject to malaria, 58
Cooper, Sir Astley, 337
Coptic alphabet, the, 177
Cordus, Euricus, account of, 330
Corn, its alteration in a subterraneous repository, 492
Corpuscular forces, on the action of, 448
Covelli, M. N., his examination of Vesuvius, 226
Crambe maritima, on its cultivation, 497
Currants, preserved upon the bushes, 169
Curves, on the beauties contained in the oval and elliptic, by R. R.
Reinagle, R.A., 1
Cyanic acid, on the composition of, 203
Dahlies, on, by Mr. William Smith, 170
Dahlia, display of beautiful varieties of the, 426
Dalmahoy, epitaph for, 334
Danaus, his migration from Egypt to Greece, 185
Davy, Sir Humphry, experiments by, 62
Denham, Major, 55
Desideratum in naval architecture, stated, 32
Désormes, M. Clement, on the action of a current of air, and the
pressure of the atmosphere, 193
Deutoxide of barium, preparation of, 474
Diamonds, formed into single lenses for microscopes, 15
Diamond lenses, letter of Mr. G. Dakin, 459
Diet, attention to, essential to travellers in tropical countries, 55
Diffraction, theory of, 434
Dominica, fever at, 59
Douglas, Mr. David, 191, 383
Douglasia, a new genus of plants, described, 383
Dragon’s blood, new substance contained in, 218
Drowning, recovery from, 231
Duncan, Sir William, M.D., 344
Dumas, M., on the properties of sulphur, 468
Dutrochet, Dr., his experiments, 77
Ear, physiology of the, 67
Edwards, Dr. W. F., De l’Influence des Agens Physiques sur la Vie,
137
Egg-plants, on the esculent, by Mr. A. Mathews, 167
Egyptian history, on the recent elucidations of early, 176
Electric currents, use of feeble, by M. Becquerel, 462
Electrical excitation, M. Walcker on, 201
Electricity, 62
Elephant, number of species unknown, 365
Elephants, carnivorous, 356
Elephants, remains discovered near Belturbet, remarks thereupon, 354
― still existing in North America, 356
Enchorial inscriptions, 310
Encke, Professor, on the return of the periodical comet, 428
Engiscope, improved Amician, 200
Engle, M., his mode of preserving paper, 198
English language, on the character of the, 93
Ethers, on the mutual action of these and other substances, 221
Etruscan vases; illustrations given, 12
Europe, climate of its various divisions, 40
Evelyn, Alexander, Esq., 190
Exodus, disquisition relative to the date of the, 186
Faraday, Mr., his Chemical Manipulation, 61
― ―, his experiments on the disinfecting soda liquid, 84
Faro in Sicily, remarkable effects of malaria, 51
Fashion destructive of taste, 14
Ferro-prussiate of potash, on its preparation, by M. Gautier, 207
Fever attendant on the houses of the opulent at Rome, 52
Fever, causes of intermittent, 40 _et seq._
Fish, on the naturalisation of, by Dr. Mac Culloch, 320
― Chinese method of fattening, 234
― subjected to experiments by Dr. Edwards, 297
Fish-store or depot, recommended by Dr. Mac Culloch for London, 328
Flora Danica, coloured set of the, 192
Fluidity, of sulphur and phosphorus, by Mr. Faraday, 469
Fluoric acid and fluates, experiments on, 205
Fog from across the sea, a vehicle of ague, 46
Fossil bones and remains, 353
France, large districts of, insalubrious, 57
Frigates, large French, with curvilinear sterns 36
Friction diminished by the use of soapstone, 455
Fruits, the specification of those of the best quality, displayed
before the Horticultural Society, 192
Fruit-trees, on planting the alluvial banks of rivers with, 170
― on walls, protecting frame for, 167
Fuel, on the varieties of, and the apparatus for their combustion,
by M. Bull, 378
Gadus Polachius, the, [or whiting pollack], 73
Gaseous exhalations of the skin, upon the, 230
Gases, on the specific heat of, by MM. de la Rive and Marcet, 200
Galvanism, effects of it in cases of asphyxia by submersion, 230
Gardening among the Romans, 264
― landscape, 270
― ornamental, 268
Genus of plants, discovered in North America, by Mr. David Douglas,
383
Gold, compounds of, 209.
―, a native argentiferous, M. Boussingault’s tables of, 225
Gore, Mr. R. T., 377
Goring’s, Dr., modification of the Amician reflector, 15, 199
Gower, Charles, M.D., his humour, 334
Gowrie, Carse of, 39
Grammar, English, disquisition respecting, 95
Grapes, observations on the growth of early and late, by M. J. Acon,
159
Grapes of the Portugal yellow fruit, grown at Hampstead, 426
Greece subject to autumnal fevers, 56
Greeks, ancient, uninfluenced by arbitrary fashions, 14
Grindall, Richard, sketch of, 335
Grose, Captain, Samuel, 453
Guido, his Aurora, 11
Hachette, M., 193
Hannibal’s line of march indicated by the fossil remains of his
elephants, 368
Hare’s, Dr., experiments on opium, 215
Hayes, Captain, 28
Head, Captain, _Rough Notes_ of, 494
Heat, its evolution during the compression of water, 201
Hecquet, Philip, the prototype of Dr. Sangrado, 331
Henderson’s, Mr. T., calculations of lunar phenomena, 450
Henry, Dr., his style, 61
Hieroglyphical fragments with some remarks on English grammar, 92
― ― illustrative of inscriptions in the British Museum, 310
Hieroglyphic Catalogue of the Egyptian kings, discovered, 182
Hieroglyphics, their language, 92
― the old Chinese, 94
Hippopotamus, the, 362
History of Egypt developed by the modern science in hieroglyphics,
178
Holbeck Spa, in Yorkshire, 21
Holland, calculation as to the duration of life in, 58
Holly trees and hedges in Scotland, described by Joseph Sabine,
Esq., 174
Horticultural Society, communications to the, 168
― ― proceedings of the, 190, 425
Horticulture, modern improvements of, 261
Howship, Mr., 249
Hoya, description of the several plants of the genus, 164
Human organization and phenomena, 303
Humboldt, letter to the Baron, 92
Hunter, Dr., 50
Hunter’s, Dr., anatomical lectures, 336
Huskisson, Mr., his speech on the shipping interests, 35
Hyposulphuric acid, its preparation, 473
Iceland moss, on a new acid existing in, 484
Indigo and indigogene, M. Liebeg on, 220
Injection, cold, for anatomical preparations, 461
Inman’s, Dr., naval constructions, 28
Insects, method of putting them to death, 493
Instrument to enable young persons to acquire a knowledge of the
stars, by S. Lee, Esq., 371
Iodous Acid, on, 204
― ― preparation of, 466
Italy, its shores pestilential in summer, 41, 56
Jalapia, uncertain nature of, 483
Jamaica, malaria, at, 50
Jebb, Sir Richard, M. D., his blunt manner of speech, 333
John of Gaddesden, surgeon, 336
Josephus, his extracts from the history of Manetho, 180
Karnac at Thebes, palace of, 184
Kings of Egypt, chronological list of the, 180
Kinic acid prepared without alcohol, 482
Kitchen gardening, 272
Knight, T. A., Esq., on the culture of celery, 166
― ― on the culture of the mango and cherimoyer, 190
Labarraque, M., his chloride of oxide of sodium, 84
Lamprey, sea, described, 72
Laudanum, denarcotized, 215
Lens, diamond, art of forming it, 15
Lenses, sapphire, Mr. Pritchard’s, 459
Leopards, the breed of dogs crossed with, 365
Liebeg, M. Just, 210
Light, undulatory theory of, by M. Fresnel, 113, 431
― duration of its effects upon the eye, 457
― its effects on vegetation, 490
― on the apparent decomposition of white, 458
― on the measurement of the intensity of, 457
Lightning, destruction of an oak by, 487
Lignin or woody fibre, 481
Lime and litharge, their mutual action, 475
Lime, on the incandescence and light of, 201
Lindley, Mr. J., his account of a new genus of plants, 109
Lines, theory respecting beauty in, 2
Linnæus, the sexual system of, 269
Liquefaction of gaseous substances, experiments of Sir H. Davy, 62
Lister, Mr. J., 248
Lithotrity, reward adjudged to M. Civiale for his discovery of, 230
Litmus as a test, fallacy of the infusion of, 214
Lloyd’s list, calculation of shipwreck from, 26
Lucretius, reference to, 62
Luminous appearances in the atmosphere, 222
Lunar observation, rule for the correction of a, by Mr. W. Wiseman,
135
Lunar phenomena, calculations of, by T. Henderson, Esq., 450
Mac Culloch, Dr. J., review of his Essay on Malaria, 100
Madder, purification of, 219
Magnetic repulsion, results of M. Becquerel’s experiments, 202
― effects of metals in motion, on the, 456
Malaria, an Essay on the production and propagation of, by Dr. Mac
Culloch; reviewed, 39, 100
― accompanying fogs, 48
Mammiferæ, observations on, 305
Mammoth, the, considered to be fabulous, 371
Man, remarkable hairy, in Ava, 493
Mandouei, King, inscription at Karnac bearing this name, 188
Manetho, his history of Egypt written in Greek, 179
Manganesic acid, on, by M. Unverdorben, 204
Manganese, new chloride of, discovered by M. J. Dumas, 475
Mango-Capac, suppositions respecting him, 359, 360
Mangosteen, living plants introduced from the East Indies, by
Captain Drummond, 191
Mantua, Napoleon’s precautions against sickness before, 54
Mapp, Mrs., celebrated bone-setter, 341
Maremma of Tuscany, 58
Mastodon, the bones of the, 356
Mathews, Mr. Andrew, 167
Maurandya Barclaiana, a new Mexican flower, 425
Mayerne, Sir Theodore, M.D., 340
Mayo, Dr. Herbert, on the sensitive plant, 76
Meadows, drains in, cause malaria and fever, 104
Meconic acid, Dr. Flare’s method of obtaining, 217.
Medical garden, Mrs. Gape’s, 338
Melons, grown on open borders, 172
Mellitic acid, preparation of pure, 483
Memnon, or Amenophis, statue of, 181
Mems., Maxims, and Memoirs, by W. Wadd, Esq., 329
Menes, monarch of Egypt, 180.
Mental powers affected by residence in a pestilential climate, 58
Merchantmen, bad construction of British, 26
Merritt’s statistical notices of the population of the British
empire, 283
Metals, three supposed new, discovered by Professor Psaun, 478
Meteoric fire-ball at New Haven, 487
― phenomenon described by Chladni, 488
Meteorological diary for June, July and August, 1827, 236
― ― for September, October, and November, 500
― Essays by Mr. Daniell, 379
― observations at Chiswick, plan of a journal of, 169
Mexico founded by the Aztecs, 359
Microscope, Dr. Brewster quoted respecting the improvement of the, 17
― with a double convex diamond lens, 17
― with sapphire lenses, 406
Mimosa Pudica, observations on the motion of its leaves, 76
Moist air, the chief conductor of malaria, 46
Moisture and heat, effects of their combination, 41
Moles, destruction of, 232
Montezuma’s address to Cortez, relative to his ancestors, 359
Montfalcon, medical observation by, 45
Moon, on the supposed influence of the, by M. Arago, 222
Morphia, its extraction from dry poppy heads, 216
Nantes, 57
Narcotine, pure, its preparation, 483
Naval construction, observations on the state of the English, 25
Naval revision, commissioners of, 27
Nitre, peculiar formation of, 205
Nitric acid, test for the presence of, 205
― ― on a peculiar, by Mr. Phillips, 467
Northern light, or streamers, described, 405
Notes to books condemned, 97
Nubia, monuments of, 184
Nugæ Canoræ, or Epitaphian Mementos of the Medici Family of Modern
Times, 329
Nugæ Chirurgicæ, or a biographical miscellany, by W. Wadd, Esq., 329
Object-glasses of M. M. Chevalier, the aplanatic, 248
Ohio, the American man of war, 35
Old system of ship-building, evils entailed by it, 35
Opium, Dr. Hare’s test of the presence of, 215
Orache, varieties of, and cultivation of, by Mr. W. Townshend, 170
Orchards, and orchard fruit, 271
Osymandyas, statues of, the Mandouei of the inscription at Karnac,
189
Oval and elliptic curves, evidenced in the motion of ships, the form
of feathers, leaves, and fruits, 13
Ovals, formed into elegant diagrams, 6
Ousirei, tomb of king, discovered by Belzoni, 187
Owl, the Coquimbo, 494
Oxalate of lime, existence of its crystals in plants, 214
Oxygen gas, 141
Paintings, Egyptian sepulchral, discovered by Belzoni, 187
Paper, preservation of it from humidity, 198
Parian marbles, the, 185
Passifloras, eatable, 169
Pears, five varieties of, from Jersey, 173
― the most celebrated, 426
Pendulum apparatus, the Milan, 155
― experiments on Mont Cenis, by Professor Carlini, 153
Penitentiary in Westminster, 52
Pennsylvania, the extraordinary length of this American first-rate,
35
Persian monarchs, their names in the Phonetic characters of Egypt,
188
Peter the Great, anecdote of, 338
Petromyzon Marinus, description of the, 72
Petroleum wells, Burmese, 490
Pharaohs, dynasty of the, 178
Philæ, inscription on the base of the obelisk of, 178
Phillips, Mr. Richard, 258
Philosophical Transactions of the Royal Society of London for 1827,
part II. contents, 379
Phonetic characters of the Egyptians, 176
Phosphorus, crystallization of, 206
―, solutions of it in oils, 206
―, its fluidity at common temperatures, 469
Phosphoric acid, its singular habitude with albumine, 473
Physical agents, on the action of, 137 _et seq._
Physicians, college of, the new and old buildings, 332
Physiology, 139
Pine apples preserved by removing their crowns, 228
Pine-cone, enormous, of Pinus strobus, from the river Columbia, 191
Pitcairn, Dr., his treatment of fever, 332
Planting of trees a safeguard against contagious winds, 53
Plants, on acclimatizing, at Biel, in East Lothian, 164
― report upon the new or rare, at Chiswick, 167
Platina, Dobereener’s, finely divided, 477
Pleischel, M., 201
Plough, use of the, in excavating canals, 197
Polypi, cure of nasal, 232
Pomological Magazine, the, 427
Pontine marshes, the, 53
Pope, cause of the poet’s death, 76
Porcelain pottery, its analysis by M. Berthier, 478
Portsmouth dockyard, education of architects for the royal navy, 26
― Duchess of, admonished by her physician, 331
Potash, ferro-prussiate of, remarks on M. Gautier’s preparation, 484
― sulphate of, 467
Powder, on the inflammation of, when struck by brass, 207
Power, microscopic, of various lenses, 20
Priestley, Dr., on the relation of gases to respiration, 141
Pritchard, Mr. A., on the forming of diamonds into microscopic
lenses, 15
Prothéeïte, a new mineral, discovered in the Tyrol, 226
Proto-carbazolate of mercury, 213
Prout, Dr., on the composition of simple alimentary substances, 481
Quadrupeds, remarks on some supposed to be extinct, 350
Quartz, peculiar crystals of, by Mr. W. Phillips, 223
Quinia, rewards for the discovery, 229
―, sulphate of, preparation of, 482
Raffles, Sir Stamford, relates that the tapir exists in Sumatra, 361
Raphael, his painting of the dispute on the sacrament, 11
― principle in his compositions, 11
Raspberries, red and white Antwerp, 169
Red cabbage, infusion of, a chemical test, 278
Reevesia, new genus of plants named, 109
Reeve, Dr. Thomas, 344
Reeves, Mr., genus of plants sent by him from China, and named
Reevesia, 109
Reflector, Amician, 17
Refraction, single, its superior light, 16
Reinagle, R. R., Esq., discourse on the oval and elliptic curves, 1
Repulsions, on peculiar physical, by M. Saigny, 455
Reynolds, Henry Revell, M.D., his personal elegance, 334
Rheine, a new substance from rhubarb, 218
Rhubarb, Buck’s (rheum undulatum), 168
― upon forcing garden, by Mr. W. Stothard, 173
Rive, M. A. de la, observations on bromine, 465
Robertson, Mr. John, on fruit-trees, 170
Rocks under the surface of the sea, how discoverable, 198
Rome; accidental causes of malaria, 51
Rosa Indica, branches budded upon the, 190
Roses, method of increasing the odour of, 228
Rosetta stone, the, its importance to learning and history, 178
Rowing pins in boats, means of securing them, 460
Royal Society, proceedings of the, 424
Royal Navy, architectural education for this service, 26
Rubens, the coronation of Mary de Medicis: character of the
composition, 11
Sacchara, tablets transmitted by Mr. Salt from, 311
Sail, quantity of in ships, 36
Salad-herbs, on growing them at sea, 233
Salamanders subjected to experiments, 142
San Quintino, letter to the Cavaliere, with remarks on M.
Champollion’s opinions, 310
Savart, M. Felix, 67
Sapphire lenses, by Mr. A. Pritchard, 459
Scarborough, Sir Charles, his works, 331
Screws, on the adhesion of, 453
Sea-kale, on the cultivation and forcing of, 497
Selenic acid, 472
Selenium and oxygen-selenic acid, new compound of, 471
Selenium, its separation from sulphur, 470
Sensitive plant, Dr. Mayo’s observations on its leaves, 76
Seppings, Sir R., vessel built on his system, 28
Ship-builders, 27
Ship-building, great principles of the art of, 31
Ships, French, their great relative length, 31
Ships with four masts, 37
Shisak, king of Egypt, identified in the inscriptions at Bubaste, 185
Sicily, insalubrious villages of, 45
Sickness and death of Prince Henry in 1612, 340
Sienna, mortality at, 56
Skeleton of an elephant in a tomb at Mexico, 359
Smith, Mr. W., on the varieties of the dahlia, 170
Smyth’s, Captain, respecting the climate of Sicily, 45
Snails, their destruction by common salt, by M. Em. Rousseau, 493
Soapstone used in diminishing friction, 455
Soda liquid, disinfecting of, M. Labarraque, 84
Soleb, on the river Nile, 184
Solubility of substances by heat diminished, 202
Sowando in Russia, fall of the lake, 227
Spallanzani, investigations of, 142
Spawn of fishes, Chinese method of transporting the, 327
Squadrons, experimental, 29
Squalls of wind on the African shores, 486
Stanley, near Wakefield, mineral spring at, 21
Stars, Mr. Lee’s instrument for gaining an early knowledge of them,
371
Statistical Notices by Mr. Merritt, 283
Steam and heat, experiments by Mr. Perkins, 461
Steam-engines, improvement in, 453
Stoop, on the means used with the intention of curing a, by Mr.
Shaw, 237
Stoves, heating them by hot water, 174
Strawberries, novel method of cultivating, 168
Street, Mr. John, on acclimatizing plants, 164
Strix Cunicularia, or Coquimbo owl, 494
Sulphate of copper, its decomposition by tartaric acid, 208
Sulphocyanide of potassium in saliva, 208
Sulphur, on certain properties of, 468
Tar-water introduced as a remedy by Bishop Berkeley, 342
Tattam, Mr., his Coptic grammar, 92
Tests, chemical; litmus paper and turmeric paper, 279
Theory of the oval and ellipse, applied to an historical composition
of Raphael, 11
Thomas Dawson, M.D., his marriage, 330
Thomson, Dr. Thomas, 60, 64
Thought, experiments on, 308
Tic douloureux, on, 346
― ―, surmise respecting its cause and nature, 108
Tirhakah, king of Ethiopia, 185
Transportation of fishes, 326
Trufle, organization and reproduction of the, 491
Tulley’s, Mr. W., double object-glass, 254
Turner, Dr. Edward, 60
Turtle, fossil remains of the, 364
Tobacco, a preventative against disease, 55;
old song on, 38
Tollet, Geo., Esq., on the preservation of apples, 168
Tooke, Horne, his grammatical in inquiries, 95
Torpid animals, experiments on, 300
Torpor, vegetable, 228
Transpiration; inquiry of Dr. Edwards into the causes of
perspiration, 151
Tusks, species of elephants without, 365
Tychsen, M., of Gottingen, 316
Varley, Mr., 17.
Vases, Etruscan, 12
Vases, formed from the oval, 7
Villa Borghese, deserted, 52
Ville de Paris, the, her proportions, 33
Viper, bite of the, remedies, 232
―, on the poison of the, 232
Vegetable diet important, in Africa and Hindostan, 55
Vegetable substances, condensed, and preserved for ships’
provisions, 229
Velocity, the great purpose of naval construction, 34
Vesuvius, Mount, 226
Vogel, M. on heavy muriatic ether, and chloric ether, 204
Undulations of light, theory of the, 113
Unicorn, the, 362
Wadd, W., Esq., 346
Watson, Sir William, his treatise on time, 310
Wild-beasts, their destruction by the Romans and Moguls, 366
Wilkes, John, his flashes of wit, 345
Wilkinson’s, Mr., inscriptions, 319
Willaumez, Admiral, his frigates having a round stern, 36
Wine, M. A. Chevalier’s tests for the natural colouring matter of,
215
Wiseman, Mr. W., on the correction of lunar observations, 135
West, Mr. William, his analysis of a mineral water, 22
Wohler’s, M., cyanic acid, 203
Wollaston, Dr., 67, 276
Woods and coppices, occasioning disease, 104
Woodville, Dr., his death, 345
Writing, indelible, 223
Writing, the formal Egyptian, 177
Young, Dr., 113, 316, 318.
Zinc, preparation of pure oxide of, by M. Hermann, 476
Printed by WILLIAM CLOWES, Stamford Street.
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Large curly brackets, "{" or "}", used to indicate combination or
grouping of information on two or more lines, have been eliminated
from this ebook. In some cases, the large brackets have been replaced
by "{" or "}" on multiple lines. Otherwise the information has been
recast if necessary, preferring minimal changes, to retain the
original meaning.
The original Journal of July–December, 1827 was evidently printed in
two parts, at different times. The title page of the first part (page
1) was printed with a footer "JULY–OCT. 1827.". The title page of the
second part (page 237) contained a similar footer "OCT.–DEC. 1827.".
The text of these footers have been moved into the titles on the same
pages.
The Table of Contents for the first part was labeled "_Jul.–Oct._
1827" The Table of Contents for the second part was not similarly
labeled, but the transcriber has inserted a label "_Oct.–Dec._ 1827".
The separate Tables of Contents have been placed together at the
beginning of this edition. The section titled "Proceedings of
the Horticultural Society." that starts on page 190 originally had no
entry in the Table of Contents; such an entry has been inserted. The
original Table of Contents for part one did not include a reference
to the Meteorological Diary for Jun–Aug; such a reference has been
inserted. The two Meteorological Diaries were originally printed as
three-month tables, approximately 7.4 inches wide by 3.9 inches,
turned 90°, using 6.5 point type. These tables have been divided into
three tables each—one for each month.
Page 31: In the phrase "ratio of which to the breadth has been
augmented by them from about 3-1/4.1, to 4.1", the phrase "3-1/4.1"
apparently denotes a ratio of 3.25:1, and "4.1" must mean a ratio 4:1.
Pages 136 and 137: The characters, such as M′, S′, M, S, etc.
denoting mathematical variables were originally printed in italics.
This notation has been discarded on these pages.
Page 194: In the text following 'M. Hachette says, “The air',
there was no closing quotation mark. Three quotation marks have
been inserted, to close the paragraph, and to enclose the apparent
quotation in the paragraph below.
Page 223: There is an equation that originally ended
"sin. [(_n_−1) 30° + 124° 8′)]". The last right parenthesis is not
balanced, and has been removed.
Page 227: There was no closing quotation mark for the quotation begun
on the previous page; such a mark has been added at the end of the
first paragraph.
Page 253: "sufficient far" was changed to "sufficient for".
Page 277: "Chemical apparhtus" was changed to "Chemical apparatus".
Page 288: "rea advantages" was changed to "real advantages".
Page 313: The quotation mark immediately following 'It begins
immediately with' has no closing quote. This structure has been
retained.
Page 315: "children, for ever. 28" was changed to "children, for
ever. (28)".
Page 376: In "bring the scale L to cnt it", "cnt" was changed to
"cut".
Page 425: "council,) the chair" was changed to "council, (the chair".
Page 428: in the table of Elements, the two "}" replace one big "}",
meant to suggest that the text "Mean Equinox 1829 Jan.9.72" goes with
both lines.
Page 451: The large table (originally 7.0 inches wide by 3.8 inches,
turned 90°, printed in 9 point type) was divided into two parts,
retaining the first column in both parts. The table on page 452 was
restructured to three columns instead of six.
Page 455: For the quotation begun 'Bailey of Boston, says, “I
understand', a closing quotation mark has been inserted at the end of
the paragraph.
Page 459: "74° − 32° = 42° .00305 × 42" was changed to "74° − 32° =
42°; .00305 × 42". And "and 30.597 + 052 = 30.649" was changed to
"and 30.597 + .052 = 30.649".
Page 463: In "The effects are produced either with or without access
to air", "to" was illegible, and has been inserted.
Page 479: The larger table ("Crucibles, &c.") has been divided into
two tables.
Page 491: The quotation beginning 'Troy, April 30, 1827. “Clouds
and rain' had no close quote. New quotation marks were inserted at
the end of that paragraph, and around the apparent quotation in the
following paragraph.
Scans of the original printed book are available from
archive.org/details/quarterlyjournal37roya. Based on the stated
scanning rate of the Internet Archive copy, the Journal page size was
about 4.3 inches wide by 7.8 inches high. The first paragraph of the
first article on Page 1, "On the Beauties . . .", which is typical of
an html h2 level article, was printed in a column 3.7 inches wide,
using type with height 11 points, with 2 points leading between
lines. The heading "III. Natural History" on page 486 is a typical
html h3 level heading. It was printed in 9 point small caps type.
The paragraph below it, a typical h4 level article, was printed in 9
point type, with no leading.
*** End of this LibraryBlog Digital Book "Quarterly Journal of Science, Literature and the Arts, July-December, 1827" ***
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