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Title: Scientific American Supplement, No. 360, November 25, 1882
Author: Various
Language: English
As this book started as an ASCII text book there are no pictures available.
Copyright Status: Not copyrighted in the United States. If you live elsewhere check the laws of your country before downloading this ebook. See comments about copyright issues at end of book.

*** Start of this Doctrine Publishing Corporation Digital Book "Scientific American Supplement, No. 360, November 25, 1882" ***

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Scientific American Supplement. Vol. XIV, No. 360.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.

       *       *       *       *       *

                         TABLE OF CONTENTS.

I.    ENGINEERING AND MECHANICS.--Soaking Pits for Steel Ingots.
      --On the successful rolling of steel ingots with their own
      initial heat by means of the soaking pit process. By JOHN GJERS.
      6 figures.--Gjers' soaking pits for steel ingots.

      Tempering by compression.--L. Clemandot's process.

      Economical Steam Power. By WILLIAM BARNET LE VAN.

      Mississippi River Improvements near St. Louis, Mo.

      Bunte's Burette for the Analysis of Furnace Gases. 2 figures.

      The "Universal" Gas Engine. 8 figures.--Improved gas engine.

      Gas Furnace for Baking Refractory Products. 1 figure.

      The Efficiency of Fans. 5 figures.

      Machine for Compressing Coal Refuse into Fuel. 1 figure.--
      Bilan's machine.

      Hank Sizing and Wringing Machine. 1 figure.

      Improved Coke Breaker. 2 figures.

      Improvements in Printing Machinery. 2 figures.

II.   TECHNOLOGY AND CHEMISTRY.--Apparatus for Obtaining
      Pure Water for Photographic Use. 3 figures.

      Black Phosphorus.--By P THENARD.

      Composition of Steep Water

      Schreiber's Apparatus for Revivifying Bone Black. 5 figures.--
      Plant: elevation and plan.--Views of elevation.--Continuous

      Soap and its Manufacture from a Consumer's Point of View.
      (Continued from SUPPLEMENT, No. 330).

      Cotton seed Oil.--By S. S. BRADFORD.

      On some Apparatus that Permit of Entering Flames.--Chevalier
      Aldini's wire gauze and asbestos protectors.--Brewster's account
      of test experiments.

III.  ELECTRICITY, LIGHT. ETC.--On a New Arc Electric Lamp.
      By W. H. PREECE. 6 figures--The Abdank system.--The lamp.--
      The Electro-magnet.--The Cut-off.--The electrical arrangement.

      Utilization of Solar Heat.

IV.   NATURAL HISTORY.--The Ocellated Pheasant. 1 figure.

      The Maidenhair Tree in the Gardens at Broadlands, Hants,
      England. 1 figure.

      The Woods of America.--The Jessup collection in the American
      Museum of Natural History, Central Park, and the characteristics
      of the specimens.

V.    AGRICULTURE, ETC.--An Industrial Revolution.--Increase in
      the number of farms.

      A Farmer's Lime Kiln. 3 figures.

      The Manufacture of Apple Jelly.

      Improved Grape Bags. 4 figures.

VI.   ARCHITECTURE, ETC.--The Building Stone Supply.--Granite
      and its sources.--Sandstone.--Blue and gray limestone.--Marble.--
      Slate.--Other stones.--A valuable summary of the sources and uses
      of quarry products.

VII.  ASTRONOMY. ETC.--How to Establish a True Meridian. By
      Prof. L. M. HAUPT.--Introduction.--Definitions.--To find the
      azemuth of Polaris.--Applications, etc.

VIII. MISCELLANEOUS.--A Characteristic Mining "Rush."--The
      Prospective Mining Center of Southern New Mexico.

      The Food and Energy of Man. By Prof. DE CHAUMONT.--Original
      food of man.--Function of food.--Classes of alimentary
      substances.--Quantity of food.--Importance of varied diet.

      Rattlesnake Poison.--Its Antidotes. By H. H. CROFT.

      The Chinese Sign Manual.--The ethnic bearing of skin furrows
      on the hand.

      Lucidity.--Matthew Arnold's remarks at the reopening of the
      Liverpool University College and School of Medicine.

       *       *       *       *       *



By Mr. JOHN GJERS, Middlesbrough.

[Footnote: Paper read before the Iron and Steel Institute at Vienna.]

When Sir Henry Bessemer, in 1856, made public his great invention, and
announced to the world that he was able to produce malleable steel from
cast iron without the expenditure of any fuel except that which already
existed in the fluid metal imparted to it in the blast furnace, his
statement was received with doubt and surprise. If he at that time had
been able to add that it was also possible to roll such steel into a
finished bar with no further expenditure of fuel, then undoubtedly the
surprise would have been much greater.

Even this, however, has come to pass; and the author of this paper
is now pleased to be able to inform this meeting that it is not only
possible, but that it is extremely easy and practical, by the means to
be described, to roll a steel ingot into, say, a bloom, a rail, or other
finished article with its own initial heat, without the aid of the
hitherto universally adopted heating furnace.

It is well understood that in the fluid steel poured into the mould
there is a larger store of heat than is required for the purpose
of rolling or hammering. Not only is there the mere apparent high
temperature of fluid steel, but there is the store of latent heat in
this fluid metal which is given out when solidification takes place.

It has, no doubt, suggested itself to many that this heat of the ingot
ought to be utilized, and as a matter of fact, there have been, at
various times and in different places, attempts made to do so; but
hitherto all such attempts have proved failures, and a kind of settled
conviction has been established in the steel trade that the theory could
not possibly be carried out in practice.

The difficulty arose from the fact that a steel ingot when newly
stripped is far too hot in the interior for the purpose of rolling, and
if it be kept long enough for the interior to become in a fit state,
then the exterior gets far too cold to enable it to be rolled
successfully. It has been attempted to overcome this difficulty
by putting the hot ingots under shields or hoods, lined with
non-heat-conducting material, and to bury them in non-heat-conducting
material in a pulverized state, for the purpose of retaining and
equalizing the heat; but all these attempts have proved futile in
practice, and the fact remains, that the universal practice in steel
works at the present day all over the world is to employ a heating
furnace of some description requiring fuel.

The author introduced his new mode of treating ingots at the Darlington
Steel and Iron Company's Works, in Darlington, early in June this year,
and they are now blooming the whole of their make, about 125 tons a
shift, or about 300 ingots every twelve hours, by such means.

The machinery at Darlington is not adapted for rolling off in one heat;
nevertheless they have rolled off direct from the ingot treated in the
"soaking pits" a considerable number of double-head rails; and the
experience so gained proves conclusively that with proper machinery
there will be no difficulty in doing so regularly. The quality of the
rails so rolled off has been everything that could be desired; and as
many of the defects in rails originate in the heating furnace, the
author ventures to predict that even in this respect the new process
will stand the test.

Many eminently practical men have witnessed the operation at Darlington,
and they one and all have expressed their great surprise at the result,
and at the simple and original means by which it is accomplished.

The process is in course of adoption in several works, both in England
and abroad, and the author hopes that by the time this paper is being
read, there may be some who will from personal experience be able to
testify to the practicability and economy of the process, which is
carried out in the manner now to be described.

A number of upright pits (the number, say, of the ingots in a cast) are
built in a mass of brickwork sunk in the ground below the level of the
floor, such pits in cross-section being made slightly larger than that
of the ingot, just enough to allow for any fins at the bottom, and
somewhat deeper than the longest ingot likely to be used. In practice
the cross section of the pit is made about 3 in. larger than the large
end of the ingot, and the top of the ingot may be anything from 6 in. to
18 in. below the top of the pit. These pits are commanded by an ingot
crane, by preference so placed in relation to the blooming mill that the
crane also commands the live rollers of the mill.

Each pit is covered with a separate lid at the floor level, and after
having been well dried and brought to a red heat by the insertion of hot
ingots, they are ready for operation.

As soon as the ingots are stripped (and they should be stripped as early
as practicable), they are transferred one by one, and placed separately
by means of the crane into these previously heated pits (which the
author calls "soaking pits") and forthwith covered over with the lid,
which practically excludes the air. In these pits, thus covered, the
ingots are allowed to stand and soak; that is, the excessive molten
heat of the interior, and any additional heat rendered sensible during
complete solidification, but which was latent at the time of placing
the ingots into the pit, becomes uniformly distributed, or nearly so,
throughout the metallic mass. No, or comparatively little, heat being
able to escape, as the ingot is surrounded by brick walls as hot as
itself, it follows that the surface heat of the ingot is greatly
increased; and after the space of from twenty to thirty minutes,
according to circumstances, the ingot is lifted out of the pit
apparently much hotter than it went in, and is now swung round to the
rolls, by means of the crane, in a perfect state of heat for rolling,
with this additional advantage to the mill over an ingot heated in an
ordinary furnace from a comparatively cold, that it is always certain to
be at least as hot in the center as it is on the surface.

[Illustration: Fig. 2]

Every ingot, when cast, contains within itself a considerably larger
store of heat than is necessary for the rolling operation. Some of this
heat is, of course, lost by passing into the mould, some is lost by
radiation before the ingot enters into the soaking pit, and some is lost
after it enters, by being conducted away by the brickwork; but in the
ordinary course of working, when there is no undue loss of time in
transferring the ingots, after allowing for this loss, there remains a
surplus, which goes into the brickwork of the soaking pits, so that this
surplus of heat from successive ingots tends continually to keep the
pits at the intense heat of the ingot itself. Thus, occasionally it
happens that inadvertently an ingot is delayed so long on its way to the
pit as to arrive there somewhat short of heat, its temperature will be
raised by heat from the walls of the pit itself; the refractory mass
wherein the pit is formed, in fact, acting as an accumulator of heat,
giving and taking heat as required to carry on the operation in a
continuous and practical manner.


During the soaking operation a quantity of gas exudes from the ingot and
fills the pit, thus entirely excluding atmospheric air from entering;
this is seen escaping round the lid, and when the lid is removed
combustion takes place.

It will be seen by analyses given hereinafter that this gas is entirely
composed of hydrogen, nitrogen, and carbonic oxide, so that the ingots
soak in a perfectly non-oxidizing medium. Hence loss of steel by
oxidation does not take place, and consequently the great loss of
yield which always occurs in the ordinary heating furnace is entirely

The author does not think it necessary to dilate upon the economical
advantages of his process, as they are apparent to every practical man
connected with the manufacture of steel.

The operation of steel making on a large scale will by this process be
very much simplified. It will help to dispense with a large number of
men, some of them highly paid, directly and indirectly connected with
the heating department; it will do away with costly heating furnaces and
gas generators, and their costly maintenance; it will save all the coal
used in heating; and what is perhaps of still more importance, it will
save the loss in yield of steel; and there will be no more steel spoiled
by overheating in the furnaces.

The process has been in operation too short a time to give precise
and reliable figures, but it is hoped that by the next meeting of the
Institute these will be forthcoming from various quarters.

Referring to the illustrations annexed, Fig. 1 shows sectional
elevation, and Fig. 2 plan of a set of eight soaking pits (marked
A). These pits are built in a mass of brickwork, B, on a concrete
foundation, C; the ingots, D, standing upright in the pits. The pits are
lined with firebrick lumps, 6 in. thick, forming an independent lining,
E, which at any time can be readily renewed. F is a cast iron plate,
made to take in four pits, and dropped loosely within the large plate,
G, which surrounds the pits. H is the cover, with a firebrick lining;
and I is a false cover of firebrick, 1 in. smaller than the cross
section of the pit, put in to rest on the top of the ingot. This false
cover need not necessarily be used, but is useful to keep the extreme
top of the ingot extra hot. J is the bottom of the pit, composed of
broken brick and silver sand, forming a good hard bottom at any desired

Figs. 4 and 5 show outline plan of two sets of soaking pits, K K, eight
each, placed under a 25 ft. sweep crane, L. This crane, if a good one,
could handle any ordinary make--up to 2,000 tons per week, and ought to
have hydraulic racking out and swinging round gear. This crane places
the ingots into the pits, and, when they are ready, picks them out and
swings them round to blooming mill, M. With such a crane, four men and a
boy at the handles are able to pass the whole of that make through the
pits. The author recommends two sets of pits as shown, although one set
of eight pits is quite able to deal with any ordinary output from one
Bessemer pit.

In case of an extraordinarily large output, the author recommends a
second crane, F, for the purpose of placing the ingots in the pits
only, the crane, L, being entirely used for picking the ingots out
and swinging them round to the live rollers of the mill. The relative
position of the cranes, soaking pits, and blooming mill may of course be
variously arranged according to circumstances, and the soaking pits may
be arranged in single or more rows, or concentrically with the crane at

Figs. 4 and 5 also show outline plan and elevation of a Bessemer plant,
conveniently arranged for working on the soaking pit system. A A are
the converters, with a transfer crane, B. C is the casting pit with
its crane, D. E E are the two ingot cranes. F is a leading crane which
transfers the ingots from the ingot cranes to the soaking pits, K K,
commanded by the crane, L, which transfers the prepared ingots to the
mill, M. as before described.

       *       *       *       *       *


L. Clemandot has devised a new method of treating metals, especially
steel, which consists in heating to a cherry red, compressing strongly
and keeping up the pressure until the metal is completely cooled. The
results are so much like those of tempering that he calls his process
tempering by compression. The compressed metal becomes exceedingly hard,
acquiring a molecular contraction and a fineness of grain such that
polishing gives it the appearance of polished nickel. Compressed steel,
like tempered steel, acquires the coercitive force which enables it to
absorb magnetism. This property should be studied in connection with
its durability; experiments have already shown that there is no loss of
magnetism at the expiration of three months. This compression has no
analogue but tempering. Hammering and hardening modify the molecular
state of metals, especially when they are practiced upon metal that is
nearly cold, but the effect of hydraulic pressure is much greater.
The phenomena which are produced in both methods of tempering may be
interpreted in different ways, but it seems likely that there is a
molecular approximation, an amorphism from which results the homogeneity
that is due to the absence of crystallization. Being an operation which
can be measured, it may be graduated and kept within limits which are
prescribed in advance; directions may be given to temper at a
specified pressure, as readily as to work under a given pressure of
steam.--_Chron. Industr_.

       *       *       *       *       *


[Footnote: A paper read by title at a recent stated meeting of the
Franklin Institute]


The most economical application of steam power can be realized only by
a judicious arrangement of the plant: namely, the engines, boilers, and
their accessories for transmission.

This may appear a somewhat broad assertion; but it is nevertheless one
which is amply justified by facts open to the consideration of all those
who choose to seek for them.

While it is true that occasionally a factory, mill, or a water-works
may be found in which the whole arrangements have been planned by a
competent engineer, yet such is the exception and not the rule, and such
examples form but a very small percentage of the whole.

The fact is that but few users of steam power are aware of the numerous
items which compose the cost of economical steam power, while a yet
smaller number give sufficient consideration to the relations which
these items bear to each other, or the manner in which the economy of
any given boiler or engine is affected by the circumstances under which
it is run.

A large number of persons--and they are those who should know better,
too--take for granted that a boiler or engine which is good for one
situation is good for all; a greater error than such an assumption can
scarcely be imagined.

It is true that there are certain classes of engines and boilers which
may be relied upon to give moderately good results in almost any
situation--and the best results should _always_ be desired in
arrangement of a mill--there are a considerable number of details which
must be taken into consideration in making a choice of boilers and

Take the case of a mill in which it has been supposed that the motive
power could be best exerted by a single engine. The question now is
whether or not it would be best to divide the total power required among
a number of engines.

_First_.--A division of the motive power presents the following
advantages, namely, a saving of expense on lines of shafting of large

_Second_.--Dispensing with the large driving belt or gearing, the first
named of which, in one instance under the writer's observation, absorbed
_sixty horse-power_ out of about 480, or about _seven per cent_.

_Third_.--The general convenience of subdividing the work to be done,
so that in case of a stoppage of one portion of the work by reason of
a loose coupling or the changing of a pulley, etc., that portion only
would need to be stopped.

This last is of itself a most important point, and demands careful

For example, I was at a mill a short time ago when the governor belt
broke. The result was a stoppage of the whole mill. Had the motive power
of this mill been subdivided into a number of small engines only one
department would have been stopped. During the stoppage in this case
the windows of the mill were a sea of heads of men and women (the
operatives), and considerable excitement was caused by the violent
blowing off of steam from the safety-valves, due to the stoppage of the
steam supply to the engine; and this excitement continued until the
cause of the stoppage was understood. Had the power in this mill been
subdivided the stoppage of one of a number of engines would scarcely
have been noticed, and the blowing off of surplus steam would not have

In building a mill the first item to be considered is the interest on
the first cost of the engine, boilers, etc. This item can be subdivided
with advantage into the amounts of interest on the respective costs of,

_First_. The engine or engines;

_Second_ The boiler or boilers;

_Third_. The engine and boiler house.

In the same connection the _form_ of engine to be used must be
considered. In some few cases--as, for instance, where engines have to
be placed in confined situations--the form is practically fixed by the
space available, it being perhaps possible only to erect a vertical or a
horizontal engine, as the case may be. These, however, are exceptional
instances, and in most cases--at all events where large powers are
required--the engineer may have a free choice in the matter. Under
these circumstances the best form, in the vast majority of cases where
machinery must be driven, is undoubtedly the horizontal engine, and the
worst the beam engine. When properly constructed, the horizontal engine
is more durable than the beam engine, while, its first cost being less,
it can be driven at a higher speed, and it involves a much smaller
outlay for engine house and foundations than the latter. In many
respects the horizontal engine is undoubtedly closely approached in
advantages by the best forms of vertical engines; but on the whole we
consider that where machinery is to be driven the balance of advantages
is decidedly in favor of the former class, and particularly so in the
case of large powers.

The next point to be decided is, whether a condensing or non-condensing
engine should be employed. In settling this question not only the
respective first costs of the two classes of engines must be taken into
consideration, but also the cost of water and fuel. Excepting, perhaps,
in cases of very small powers, and in those instances where the exhaust
steam from a non-condensing engine can be turned to good account for
heating or drying purpose, it may safely be asserted that in all
instances where a sufficient supply of condensing water is available
at a moderate cost, the extra economy of a well-constructed condensing
engine will fully warrant the additional outlay involved in its
purchase. In these days of high steam pressures, a well constructed
non-condensing engine can, no doubt, be made to approximate closely to
the economy of a condensing engine, but in such a case the extra cost of
the stronger boiler required will go far to balance the additional cost
of the condensing engine.

Having decided on the form, the next question is, what "class" of engine
shall it be; and by the term class I mean the relative excellence of the
engine as a power-producing machine. An automatic engine costs more than
a plain slide-valve engine, but it will depend upon the cost of fuel at
the location where the engine is to be placed, and the number of hours
per day it is kept running, to decide which class of machine can be
adopted with the greatest economy to the proprietor. The cost of
lubricating materials, fuel, repairs, and percentage of cost to be put
aside for depreciation, will be less in case of the high-class than in
the low-class engine, while the former will also require less boiler

Against these advantages are to be set the greater first cost of the
automatic engine, and the consequent annual charge due to capital sunk.
These several items should all be fairly estimated when an engine is
to be bought, and the kind chosen accordingly. Let us take the item of
fuel, for instance, and let us suppose this fuel to cost four dollars
per ton at the place where the engine is run. Suppose the engine to be
capable of developing one hundred horse-power, and that it consumes five
pounds of coal per hour per horse-power, and runs ten hours per day:
this would necessitate the supply of two and one-half tons per day at
a cost of ten dollars per day. To be really economical, therefore, any
improvement which would effect a saving of one pound of coal per hour
per horse-power must not cost a greater sum per horse-power than that on
which the cost of the difference of the coal saved (one pound of coal
per hour per horse-power, which would be 1,000 pounds per day) for, say,
three hundred days, three hundred thousand (300,000) pounds, or one
hundred and fifty tons (or six hundred dollars), would pay a fair

Assuming that the mill owner estimates his capital as worth to him ten
per cent, per annum, then the improvement which would effect the above
mentioned saving must not cost more than six thousand dollars, and so
on. If, instead of being run only ten hours per day, the engine is run
night and day, then the outlay which it would be justifiable to make to
effect a certain saving per hour would be doubled; while, on the other
hand, if an engine is run less than the usual time per day a given
saving per hour would justify a correspondingly less outlay.

It has been found that for grain and other elevators, which are not run
constantly, gas engines, although costing more for the same power,
are cheaper than steam engines for elevating purposes where only
occasionally used.

For this reason it is impossible without considerable investigation to
say what is really the most economical engine to adopt in any particular
case; and as comparatively few users of steam power care to make this
investigation a vast amount of wasteful expenditure results. Although,
however, no absolute rule can be given, we may state that the number
of instances in which an engine which is wasteful of fuel can be used
profitably is exceedingly small. As a rule, in fact, it may generally be
assumed that an engine employed for driving a manufactory of any kind
cannot be of too high a class, the saving effected by the economical
working of such engines in the vast majority of cases enormously
outweighing the interest on their extra first cost. So few people appear
to have a clear idea of the vast importance of economy of fuel in mills
and factories that I perhaps cannot better conclude than by giving an
example showing the saving to be effected in a large establishment by an
economical engine.

I will take the case of a flouring mill in this city which employed two
engines that required forty pounds of water to be converted into steam
per hour per indicated horse-power. This, at the time, was considered a
moderate amount and the engines were considered "good."

These engines indicated seventy horse power each, and ran twenty-four
hours per day on an average of three hundred days each year, requiring
as per indicator diagrams forty million three hundred and twenty
thousand pounds (40 x 70 x 24 x 300 x 2 = 40,320,000) of feed water to
be evaporated per annum, which, in Philadelphia, costs three dollars
per horse-power per annum, amounting to (70 x 2 x 300 = $420.00) four
hundred and twenty dollars.

The coal consumed averaged five and one-half pounds per hour per
horse-power, which, at four dollars per ton, costs

((70 x 2 x 5.5 x 24 x 300) / 2,000) x 4.00= $11,088

Eleven thousand and eighty-eight dollars.

  Cost of coal for 300 days.                $11,088
  Cost of water for 300 days.                   420
  Total cost of coal and water.             $11,503

These engines were replaced by one first-class automatic engine,
which developed one hundred and forty-two horse-power per hour with a
consumption of _three pounds_ of coal per hour per horse-power, and the
indicator diagrams showed a consumption of _thirty_ pounds of water per
hour per horse-power. Coal cost

((142 x 3 x 24 x 300) / 2,000) x 4.00 = $6,134

Six thousand one hundred and thirty-four dollars. Water cost (142 x
3.00= $426.00) four hundred and twenty-six dollars.

  Cost of coal for 300 days.                $6,134
  Cost of water for 300 days.                  426
  Total cost of coal and water.             $6,560

The water evaporated in the latter case to perform the same work was
(142 x 30 x 24 x 300 = 30,672,000) thirty million six hundred and
seventy-two thousand pounds of feed water against (40,320,000) forty
million three hundred and twenty thousand pounds in the former, a saving
of (9,648,000) nine million six hundred and forty-eight thousand pounds
per annum; or,

(40,320,000 - 30,672,000) / 9,648,000 = 31.4 per cent.

--_thirty-one and four-tenths per cent_.

And a saving in coal consumption of

(11,088 - 6,134) / 4,954 = 87.5 per cent.

--_eighty-seven and one-half per cent_., or a saving in dollars and
cents of four thousand nine hundred and fifty-four dollars ($4,954).

In this city, Philadelphia, no allowance for the consumption of water is
made in the case of first class engines, such engines being charged the
same rate per annum per horse-power as an inferior engine, while,
as shown by the above example, a saving in water of _thirty-one and
four-tenths per cent_. has been attained by the employment of a
first-class engine. The builders of such engines will always give a
guarantee of their consumption of water, so that the purchaser can be
able in advance to estimate this as accurately as he can the amount of
fuel he will use.

       *       *       *       *       *


The improvement of the Mississippi River near St. Louis progresses
satisfactorily. The efficacy of the jetty system is illustrated in the
lines of mattresses which showed accumulations of sand deposits ranging
from the surface of the river to nearly sixteen feet in height. At Twin
Hollow, thirteen miles from St. Louis and six miles from Horse-Tail Bar,
there was found a sand bar extending over the widest portion of the
river on which the engineering forces were engaged. Hurdles are built
out from the shore to concentrate the stream on the obstruction, and
then to protect the river from widening willows are interwoven between
the piles. At Carroll's Island mattresses 125 feet wide have been
placed, and the banks revetted with stone from ordinary low water to a
16 foot stage. There is plenty of water over the bar, and at the most
shallow points the lead showed a depth of twelve feet. Beard's Island, a
short distance further, is also being improved, the largest force of men
at any one place being here engaged. Four thousand feet of mattresses
have been begun, and in placing them work will be vigorously prosecuted
until operations are suspended by floating ice. The different sections
are under the direction of W. F. Fries, resident engineer, and E. M.
Currie, superintending engineer. There are now employed about 1,200 men,
thirty barges and scows, two steam launches, and the stern-wheel steamer
A. A. Humphreys. The improvements have cost, in actual money expended,
about $200,000, and as the appropriation for the ensuing year
approximates $600,000, the prospect of a clear channel is gratifying to
those interested in the river.

       *       *       *       *       *


For analyzing the gases of blast-furnaces the various apparatus of Orsat
have long been employed; but, by reason of its simplicity, the burette
devised by Dr. Bünte, and shown in the accompanying figures, is much
easier to use. Besides, it permits of a much better and more rapid
absorption of the oxide of carbon; and yet, for the lost fractions of
the latter, it is necessary to replace a part of the absorbing liquid
three or four times. The absorbing liquid is prepared by making a
saturated solution of chloride of copper in hydrochloric acid, and
adding thereto a small quantity of dissolved chloride of tin. Afterward,
there are added to the decanted mixture a few spirals of red copper, and
the mixture is then carefully kept from contact with the air.

To fill the burette with gas, the three-way cock, _a_, is so placed that
the axial aperture shall be in communication with the graduated part, A,
of the burette. After this, water is poured into the funnel, t, and the
burette is put in communication with the gas reservoir by means of a
rubber tube. The lower point of the burette is put in communication with
a rubber pump, V (Fig. 2), on an aspirator (the cock, _b_, being left
open), and the gas is sucked in until all the air that was in the
apparatus has been expelled from it. The cocks, _a_ and _b_, are turned
90 degrees. The water in the funnel prevents the gases communicating
with the top. The point of the three-way cock is afterward closed with a
rubber tube and glass rod.

If the gas happens to be in the reservoir of an aspirator, it is made
to pass into the apparatus in the following manner: The burette is
completely filled with water, and the point of the three-way cock is
put in communication with a reservoir. If the gas is under pressure, a
portion of it is allowed to escape through the capillary tube into the
water in the funnel, by turning the cock, _a_, properly, and thus all
the water in the conduit is entirely expelled. Afterward _a_ is turned
180°, and the lower cock, _b_, is opened. While the water is flowing
through _b_, the burette becomes filled with gas.

_Mode of Measuring the Gases and Absorption_.--The tube that
communicates with the vessel, F, is put in communication, after the
latter has been completely filled with water, with the point of the
cock, _b_ (Fig. 2). Then the latter is opened, as is also the pinch cock
on the rubber tubing, and water is allowed to enter the burette through
the bottom until the level is at the zero of the graduation. There are
then 100 cubic centimeters in the burette. The superfluous gas has
escaped through the cock, _a_, and passed through the water in the
funnel. The cock, _a_, is afterward closed by turning it 90°. To
cause the absorbing liquid to pass into the burette, the water in the
graduated cylinder is made to flow by connecting the rubber tube, s, of
the bottle, S, with the point of the burette. The cock is opened, and
suction is effected with the mouth of the tube, r. When the water has
flowed out to nearly the last drop, _b_ is closed and the suction bottle
is removed. The absorbing liquid (caustic potassa or pyrogallate of
potassa) is poured into a porcelain capsule, P, and the point of the
burette is dipped into the liquid. If the cock, _b_, be opened, the
absorbing liquid will be sucked into the burette. In order to hasten
the absorption, the cock, _b_, is closed, and the burette is shaken
horizontally, the aperture of the funnel being closed by the hand during
the operation.

If not enough absorbing liquid has entered, there may be sucked into the
burette, by the process described above, a new quantity of liquid. The
reaction finished, the graduated cylinder is put in communication with
the funnel by turning the cock, _a_. The water is allowed to run from
the funnel, and the latter is filled again with water up to the mark.
The gas is then again under the same pressure as at the beginning.

After the level has become constant, the quantity of gas remaining is
measured. The contraction that has taken place gives, in hundredths of
the total volume, the volume of the gas absorbed.

When it is desired to make an analysis of smoke due to combustion,
caustic potassa is first sucked into the burette. After complete
absorption, and after putting the gas at the same pressure, the
diminution gives the volume of carbonic acid.

To determine the oxygen in the remaining gas, a portion of the caustic
potash is allowed to flow out, and an aqueous solution of pyrogallic
acid and potash is allowed to enter. The presence of oxygen is revealed
by the color of the liquid, which becomes darker.

The gas is then agitated with the absorbing liquid until, upon opening
the cock, _a_, the liquid remains in the capillary tube, that is to say,
until no more water runs from the funnel into the burette. To make a
quantitative analysis of the carbon contained in gas, the pyrogallate of
potash must be entirely removed from the burette. To do this, the liquid
is sucked out by means of the flask, S, until there remain only a few
drops; then the cock, _a_, is opened and water is allowed to flow from
the funnel along the sides of the burette. Then _a_ is closed, and
the washing water is sucked in the same manner. By repeating this
manipulation several times, the absorbing liquid is completely removed.
The acid solution of chloride of copper is then allowed to enter.

As the absorbing liquids adhere to the glass, it is better, before
noting the level, to replace these liquids by water. The cocks, _a_ and
_b_, are opened, and water is allowed to enter from the funnel, the
absorbing liquid being made to flow at the same time through the cock,

When an acid solution of chloride of copper is employed, dilute
hydrochloric acid is used instead of water.

Fig. 2 shows the arrangement of the apparatus for the quantitative
analysis of oxide of carbon and hydrogen by combustion. The gas in the
burette is first mixed with atmospheric air, by allowing the liquid to
flow through _b_, and causing air to enter through the axial aperture of
the three way cock, _a_, after cutting off communication at v. Then, as
shown in the figure, the burette is connected with the tube, B, which is
filled with water up to the narrow curved part, and the interior of the
burette is made to communicate with the combustion tube, v, by turning
the cock, a. The combustion tube is heated by means of a Bunsen burner
or alcohol lamp, L. It is necessary to proceed, so that all the water
shall be driven from the cock and the capillary tube, and that it shall
be sent into the burette. The combustion is effected by causing the
mixture of gas to pass from the burette into the tube, B, through the
tube, v, heated to redness, into which there passes a palladium wire.
Water is allowed to flow through the point of the tube, B, while from
the flask, F, it enters through the bottom into the burette, so as to
drive out the gas. The water is allowed to rise into the burette as far
as the cock, and the cocks, _b_ and _b¹_, are afterward closed.

[Illustration: DR. BÜNTE'S GAS BURETTE]

By a contrary operation, the gas is made to pass from B into the
burette. It is then allowed to cool, and, after the pressure has been
established again, the contraction is measured. If the gas burned is
hydrogen, the contraction multiplied by two-thirds gives the original
volume of the hydrogen gas burned. If the gas burned is oxide of carbon,
there forms an equal volume of carbonic acid, and the contraction is the
half of CO. Thus, to analyze CO, a portion of the liquid is removed from
the burette, then caustic potash is allowed to enter, and the process
goes on as explained above.

The total contraction resulting from combustion and absorption,
multiplied by two-thirds, gives the volume of the oxide of carbon.

The hydrogen and oxide carbon may thus be quantitatively analyzed
together or separately.--_Revue Industrielle_.

       *       *       *       *       *


The accompanying engravings illustrate a new and very simple form of gas
engine, the invention of J. A. Ewins and H. Newman, and made by Mr. T.
B. Barker, of Scholefield-street, Bloomsbury, Birmingham. It is known as
the "Universal" engine, and is at present constructed in sizes varying
from one-eighth horse-power--one man power--to one horse-power, though
larger sizes are being made. The essentially new feature of the engine
is, says the _Engineer_, the simple rotary ignition valve consisting of
a ratchet plate or flat disk with a number of small radial slots which
successively pass a small slot in the end of the cylinder, and through
which the flame is drawn to ignite the charge. In our illustrations Fig.
1 is a side elevation; Fig. 2 an end view of same; Fig. 3 a plan; Fig. 4
is a sectional view of the chamber in which the gas and air are mixed,
with the valves appertaining thereto; Fig. 5 is a detail view of the
ratchet plate, with pawl and levers and valve gear shaft; Fig. 6 is
a sectional view of a pump employed in some cases to circulate water
through the jacket; Fig. 7 is a sectional view of arrangement for
lighting, and ratchet plate, j, with central spindle and igniting
apertures, and the spiral spring, k, and fly nut, showing the attachment
to the end of the working cylinder, f1; b5, b5, bevel wheels driving
the valve gear shaft; e, the valve gear driving shaft; e2, eccentric to
drive pump; e³, eccentric or cam to drive exhaust valve; e4, crank to
drive ratchet plate; e5, connecting rod to ratchet pawl; f, cylinder
jacket; f1, internal or working cylinder; f2, back cylinder cover; g,
igniting chamber; h, mixing chamber; h1, flap valve; h2, gas inlet
valve, the motion of which is regulated by a governor; h3, gas inlet
valve seat; h4, cover, also forming stop for gas inlet valve; h5, gas
inlet pipe; h6, an inlet valve; h8, cover, also forming stop for air
inlet valve; h9, inlet pipe for air with grating; i, exhaust chamber;
i2, exhaust valve spindle; i7, exhaust pipe; j6, lighting aperture
through cylinder end; l, igniting gas jet; m, regulating and stop valve
for gas.


The engine, it will be seen, is single-acting, and no compression of the
explosive charge is employed. An explosive mixture of combustible gas
and air is drawn through the valves, h2 and h6, and exploded behind
the piston once in a revolution; but by a duplication of the valve and
igniting apparatus, placed also at the front end of the cylinder, the
engine may be constructed double-acting. At the proper time, when the
piston has proceeded far enough to draw in through the mixing chamber,
h, into the igniting chamber, g, the requisite amount of gas and air,
the ratchet plate, j, is pushed into such a position by the pawl, j3,
that the flame from the igniting jet, l, passes through one of the slots
or holes, j1, and explodes the charge when opposite j6, which is the
only aperture in the end of the working cylinder (see Fig. 7 and Fig.
2), thus driving the piston on to the end of its forward stroke. The
exhaust valve, Fig. 9, though not exactly of the form shown, is kept
open during the whole of this return stroke by means of the eccentric,
e3, on the shaft working the ratchet, and thus allowing the products of
combustion to escape through the exhaust pipe, i7, in the direction of
the arrow. Between the ratchet disk and the igniting flame a small plate
not shown is affixed to the pipe, its edge being just above the burner
top. The flame is thus not blown out by the inrushing air when the slots
in ratchet plate and valve face are opposite. This ratchet plate or
ignition valve, the most important in any engine, has so very small a
range of motion per revolution of the engine that it cannot get out of
order, and it appears to require no lubrication or attention whatever.
The engines are working very successfully, and their simplicity enables
them to be made at low cost. They cost for gas from ½d. to 1½d. per hour
for the sizes mentioned.

[Illustration: Fig.9.]

       *       *       *       *       *


In order that small establishments may put to profit the advantages
derived from the use of annular furnaces heated with gas, smaller
dimensions have been given the baking chambers of such furnaces. The
accompanying figure gives a section of a furnace of this kind, set into
the ground, and the height of whose baking chamber is only one and a
half meters. The chamber is not vaulted, but is covered by slabs of
refractory clay, D, that may be displaced by the aid of a small car
running on a movable track. This car is drawn over the compartment that
is to be emptied, and the slab or cover, D, is taken off and carried
over the newly filled compartment and deposited thereon.

The gas passes from the channel through the pipe, a, into the vertical
conduits, b, and is afterward disengaged through the tuyeres into the
chamber. In order that the gas may be equally applied for preliminary
heating or smoking, a small smoking furnace, S, has been added to
the apparatus. The upper part of this consists of a wide cylinder
of refractory clay, in the center of whose cover there is placed an
internal tube of refractory clay, which communicates with the channel,
G, through a pipe, d. This latter leads the gas into the tube, t, of the
smoking furnace, which is perforated with a large number of small holes.
The air requisite for combustion enters through the apertures, o, in the
cover of the furnace, and brings about in the latter a high temperature.
The very hot gases descend into the lower iron portion of this small
furnace and pass through a tube, e, into the smoking chamber by the aid
of vertical conduits, b', which serve at the same time as gas tuyeres
for the extremity of the furnace that is exposed to the fire.


In the lower part of the smoking furnace, which is made of boiler plate
and can be put in communication with the tube, e, there are large
apertures that may be wholly or partially closed by means of registers
so as to carry to the hot gas derived from combustion any quantity
whatever of cold and dry air, and thus cause a variation at will of the
temperature of the gases which are disengaged from the tube, e.

The use of these smoking apparatus heated by gas does away also with the
inconveniences of the ordinary system, in which the products are soiled
by cinders or dust, and which render the gradual heating of objects to
be baked difficult. At the beginning, there is allowed to enter the
lower part of the small furnace, S, through the apertures, a very
considerable quantity of cold air, so as to lower the temperature of the
smoke gas that escapes from the tube, e, to 30 or 50 degrees. Afterward,
these secondary air entrances are gradually closed so as to increase the
temperature of the gases at will.

       *       *       *       *       *


Air, like every other gas or combination of gases, possesses weight;
some persons who have been taught that the air exerts a pressure of 14.7
lb. per square inch, cannot, however, be got to realize the fact that a
cubit foot of air at the same pressure and at a temperature of 62 deg.
weighs the thirteenth part of a pound, or over one ounce; 13.141 cubic
feet of air weigh one pound. In round numbers 30,000 cubic feet of air
weigh one ton; this is a useful figure to remember, and it is easily
carried in the mind. A hall 61 feet long, 30 feet wide, and 17 feet high
will contain one ton of air.

[Illustration: FIG. 1]

The work to be done by a fan consists in putting a weight--that of the
air--in motion. The resistances incurred are due to the inertia of the
air and various frictional influences; the nature and amount of these
last vary with the construction of the fan. As the air enters at the
center of the fan and escapes at the circumference, it will be seen that
its motion is changed while in the fan through a right angle. It may
also be taken for granted that within certain limits the air has no
motion in a radial direction when it first comes in contact with a fan
blade. It is well understood that, unless power is to be wasted, motion
should be gradually imparted to any body to be moved. Consequently, the
shape of the blades ought to be such as will impart motion at first
slowly and afterward in a rapidly increasing ratio to the air. It is
also clear that the change of motion should be effected as gradually as
possible. Fig. 1 shows how a fan should not be constructed; Fig. 2 will
serve to give an idea of how it should be made.

[Illustration: FIG. 2]

In Fig. 1 it will be seen that the air, as indicated by the bent arrows,
is violently deflected on entering the fan. In Fig. 2 it will be seen
that it follows gentle curves, and so is put gradually in motion. The
curved form of the blades shown in Fig. 2 does not appear to add much to
the efficiency of a fan; but it adds something and keeps down noise. The
idea is that the fan blades when of this form push the air radially from
the center to the circumference. The fact is, however, that the air
flies outward under the influence of centrifugal force, and always tends
to move at a tangent to the fan blades, as in Fig. 3, where the circle
is the path of the tips of the fan blades, and the arrow is a tangent to
that path; and to impart this notion a radial blade, as at C, is perhaps
as good as any other, as far as efficiency is concerned. Concerning the
shape to be imparted to the blades, looked at back or front, opinions
widely differ; but it is certain that if a fan is to be silent the
blades must be narrower at the tips than at the center. Various forms
are adopted by different makers, the straight side and the curved sides,
as shown in Fig. 4, being most commonly used. The proportions as regards
length to breadth are also varied continually. In fact, no two makers of
fans use the same shapes.

[Illustration: FIG. 3]

As the work done by a fan consists in imparting motion at a stated
velocity to a given weight of air, it is very easy to calculate the
power which must be expended to do a certain amount of work. The
velocity at which the air leaves the fan cannot be greater than that of
the fan tips. In a good fan it may be about two-thirds of that speed.
The resistance to be overcome will be found by multiplying the area of
the fan blades by the pressure of the air and by the velocity of the
center of effort, which must be determined for every fan according to
the shape of its blades. The velocity imparted to the air by the fan
will be just the same as though the air fell in a mass from a given
height. This height can be found by the formula h = v² / 64; that is to
say, if the velocity be multiplied by itself and divided by 64 we have
the height. Thus, let the velocity be 88 per second, then 88 x 88 =
7,744, and 7,744 / 64 = 121. A stone or other body falling from a height
of 121 feet would have a velocity of 88 per second at the earth. The
pressure against the fan blades will be equal to that of a column of air
of the height due to the velocity, or, in this case, 121 feet. We
have seen that in round numbers 13 cubic feet of air weigh one pound,
consequently a column of air one square foot in section and 121 feet
high, will weigh as many pounds as 13 will go times into 121. Now, 121
/ 13 = 9.3, and this will be the resistance in pounds per _square foot_
overcome by the fan. Let the aggregate area of all the blades be 2
square feet, and the velocity of the center of effort 90 feet per
second, then the power expended will bve (90 x 60 x 2 x 9.3) / 33,000
= 3.04 horse power. The quantity of air delivered ought to be equal in
volume to that of a column with a sectional area equal that of one fan
blade moving at 88 feet per second, or a mile a minute. The blade having
an area of 1 square foot, the delivery ought to be 5,280 feet per
minute, weighing 5,280 / 13 = 406.1 lb. In practice we need hardly say
that such an efficiency is never attained.

[Illustration: FIG. 4]

The number of recorded experiments with fans is very small, and a great
deal of ignorance exists as to their true efficiency. Mr. Buckle is one
of the very few authorities on the subject. He gives the accompanying
table of proportions as the best for pressures of from 3 to 6 ounces per
square inch:

                  |         Vanes.         | Diameter of inlet
Diameter of fans. |------------------------|    openings.
                  |   Width.   |  Length.  |
     ft. in.      |  ft. in.   | ft. in.   |       ft. in.
      3  0        |   0   9    |  0   9    |        1   6
      3  6        |   0  10½   |  0  10½   |        1   9
      4  0        |   1   0    |  1   0    |        2   0
      4  6        |   1   1½   |  1   1½   |        2   3
      5  0        |   1   3    |  1   3    |        2   6
      6  0        |   1   6    |  1   6    |        3   0
                  |            |           |

For higher pressures the blades should be longer and narrower, and
the inlet openings smaller. The case is to be made in the form of an
arithmetical spiral widening, the space between the case and the blades
radially from the origin to the opening for discharge, and the upper
edge of the opening should be level with the lower side of the sweep of
the fan blade, somewhat as shown in Fig. 5.

[Illustration: FIG. 5]

A considerable number of patents has been taken out for improvements
in the construction of fans, but they all, or nearly all, relate to
modifications in the form of the case and of the blades. So far,
however, as is known, it appears that, while these things do exert a
marked influence on the noise made by a fan, and modify in some degree
the efficiency of the machine, that this last depends very much more on
the proportions adopted than on the shapes--so long as easy curves
are used and sharp angles avoided. In the case of fans running at low
speeds, it matters very little whether the curves are present or not;
but at high speeds the case is different.--_The Engineer_.

       *       *       *       *       *


The problem as to how the refuse of coal shall be utilized has been
solved in the manufacture from it of an agglomerated artificial
fuel, which is coming more and more into general use on railways and
steamboats, in the industries, and even in domestic heating.

The qualities that a good agglomerating machine should present are as

1. Very great simplicity, inasmuch as it is called upon to operate in
an atmosphere charged with coal dust, pitch, and steam; and, under such
conditions, it is important that it may be easily got at for cleaning,
and that the changing of its parts (which wear rapidly) may be effected
without, so to speak, interrupting its running.

2. The compression must be powerful, and, that the product may be
homogeneous, must operate progressively and not by shocks. It must
especially act as much as possible upon the entire surface of the
conglomerate, and this is something that most machines fail to do.

3. The removal from the mould must be effected easily, and not depend
upon a play of pistons or springs, which soon become foul, and the
operation of which is very irregular.

The operations embraced in the manufacture of this kind of fuel are as

The refuse is sifted in order to separate the dust from the grains of
coal. The dust is not submitted to a washing. The grains are classed
into two sizes, after removing the nut size, which is sold separately.
The grains of each size are washed separately. The washed grains are
either drained or dried by a hydro-extractor in order to free them from
the greater part of the water, the presence of this being an obstacle to
their perfect agglomeration. The water, however, should not be entirely
extracted because the combustibles being poor conductors of heat, a
certain amount of dampness must be preserved to obtain an equal division
of heat in the paste when the mixture is warmed.

After being dried the grains are mixed with the coal dust, and broken
coal pitch is added in the proportion of eight to ten per cent. of the
coal. The mixture is then thrown into a crushing machine, where it is
reduced to powder and intimately mixed. It then passes into a pug-mill
into which superheated steam is admitted, and by this means is converted
into a plastic paste. This paste is then led into an agitator for the
double purpose of freeing it from the steam that it contains, and of
distributing it in the moulds of the compressing machine.


Bilan's machine, shown in the accompanying cut, is designed for
manufacturing spherical conglomerates for domestic purposes. It consists
of a cast iron frame supporting four vertical moulding wheels placed at
right angles to each other and tangent to the line of the centers. These
wheels carry on their periphery cavities that have the form of a quarter
of a sphere. They thus form at the point of contact a complete sphere
in which the material is inclosed. The paste is thrown by shovel, or
emptied by buckets and chain, into the hopper fixed at the upper part
of the frame. From here it is taken up by two helices, mounted on a
vertical shaft traversing the hopper, and forced toward the point where
the four moulding wheels meet. The driving pulley of the machine is
keyed upon a horizontal shaft which is provided with two endless screws
that actuate two gear-wheels, and these latter set in motion the four
moulding wheels by means of beveled pinions. The four moulding wheels
being accurately adjusted so that their cavities meet each other at
every revolution, carry along the paste furnished them by the hopper,
compress it powerfully on the four quarters, and, separating by a
further revolution, allow the finished ball to drop out.

The external crown of the wheels carrying the moulds consists of four
segments, which may be taken apart at will to be replaced by others when

This machine produces about 40 tons per day of this globular artificial
fuel.--_Annales Industrielles_.

       *       *       *       *       *


We give a view of a hank sizing machine by Messrs. Heywood & Spencer,
of Radcliffe, near Manchester. The machine is also suitable for fancy
dyeing. It is well known, says the _Textile Manufacturer_, that when
hanks are wrung by hand, not only is the labor very severe, but in
dyeing it is scarcely possible to obtain even colors, and, furthermore,
the production is limited by the capabilities of the man. The machine
we illustrate is intended to perform the heavy part of the work with
greater expedition and with more certainty than could be relied upon
with hand labor. The illustration represents the machine that we
inspected. Its construction seems of the simplest character. It consists
of two vats, between which is placed the gearing for driving the hooks.
The large wheel in this gear, although it always runs in one direction,
contains internal segments, which fall into gear alternately with
pinions on the shanks of the hooks. The motion is a simple one, and it
appeared to us to be perfectly reliable, and not liable to get out of
order. The action is as follows: The attendant lifts the hank out of the
vat and places it on the hooks. The hook connected to the gearing then
commences to turn; it puts in two, two and a half, three, or more twists
into the hank and remains stationary for a few seconds to allow an
interval for the sizer to "wipe off" the excess of size, that is, to
run his hand along the twisted hank. This done, the hook commences to
revolve the reverse way, until the twists are taken out of the hank.
It is then removed, either by lifting off by hand or by the apparatus
shown, attached to the right hand side. This arrangement consists of a
lattice, carrying two arms that, at the proper moment, lift the hank off
the hooks on to the lattice proper, by which it is carried away, and
dropped upon a barrow to be taken to the drying stove. In sizing, a
double operation is customary; the first is called running, and the
second, finishing. In the machine shown, running is carried on one side
simultaneously with finishing in the other, or, if required, running
may be carried on on both sides. If desired, the lifting off motion is
attached to both running and finishing sides, and also the roller partly
seen on the left hand for running the hanks through the size. The
machine we saw was doing about 600 bundles per day at running and at
finishing, but the makers claim the production with a double machine to
be at the rate of about 36 10 lb. bundles per hour (at finishing), wrung
in 1½ lb. wringers (or I½ lb. of yarn at a time), or at running at the
rate of 45 bundles in 2 lb. wringers. The distance between the hooks
is easily adjusted to the length or size of hanks, and altogether the
machine seems one that is worth the attention of the trade.


       *       *       *       *       *


The working parts of the breaker now in use by the South Metropolitan
Gas Company consist essentially of a drum provided with cutting edges
projecting from it, which break up the coke against a fixed grid. The
drum is cast in rings, to facilitate repairs when necessary, and the
capacity of the machine can therefore be increased or diminished by
varying the number of these rings. The degree of fineness of the coke
when broken is determined by the regulated distance of the grid from the
drum. Thus there is only one revolving member, no toothed gearing being
required. Consequently the machine works with little power; the one at
the Old Kent Road, which is of the full size for large works, being
actually driven by a one horse power "Otto" gas-engine. Under these
conditions, at a recent trial, two tons of coke were broken in half an
hour, and the material delivered screened into the three classes of
coke, clean breeze (worth as much as the larger coke), and dust, which
at these works is used to mix with lime in the purifiers. The special
advantage of the machine, besides the low power required to drive it and
its simple action, lies in the small quantity of waste. On the occasion
of the trial in question, the dust obtained from two tons of coke
measured only 3½ bushels, or just over a half hundredweight per ton.
The following statement, prepared from the actual working of the first
machine constructed, shows the practical results of its use. It should
be premised that the machine is assumed to be regularly employed and
driven by the full power for which it is designed, when it will easily
break 8 tons of coke per hour, or 80 tons per working day:

    500 feet of gas consumed by a 2 horse power
      gas-engine, at cost price of gas delivered   s. d.
      in holder.                                   0  9
    Oil and cotton waste.                          0  6
    Two men supplying machine with large
      coke, and shoveling up broken, at 4s.
      6d.                                          9  0
    Interest and wear and tear (say).              0  3
         Total per day.                           10  6
    For 80 tons per day, broken at the rate
      of.                                          0  1½
    Add for loss by dust and waste, 1 cwt.,
      with price of coke at (say) 13s. 4d. per
      ton.                                         0  8
        Cost of breaking, per ton.                 0  9½

As coke, when broken, will usually fetch from 2s. to 2s. 6d. per ton
more than large, the result of using these machines is a net gain of
from 1s. 3d. to 1s. 9d. per ton of coke. It is not so much the actual
gain, however, that operates in favor of providing a supply of broken
coke, as the certainty that by so doing a market is obtained that would
not otherwise be available.


It will not be overstating the case to say that this coke breaker is by
far the simplest, strongest, and most economical appliance of its kind
now manufactured. That it does its work well is proved by experience;
and the advantages of its construction are immediately apparent upon
comparison of its simple drum and single spindle with the flying hammers
or rocking jaws, or double drums with toothed gearing which characterize
some other patterns of the same class of plant. It should be remarked,
as already indicated, lest exception should be taken to the size of the
machine chosen here for illustration, that it can be made of any size
down to hand power. On the whole, however, as a few tons of broken coke
might be required at short notice even in a moderate sized works, it
would scarcely be advisable to depend upon too small a machine; since
the regular supply of the fuel thus improved may be trusted in a short
time to increase the demand.


       *       *       *       *       *


This is the design of Alfred Godfrey, of Clapton. According to this
improvement, as represented at Figs. 1 and 2, a rack, A, is employed
vibrating on the pivot a, and a pinion, a1, so arranged that instead of
the pinion moving on a universal joint, or the rack moving in a parallel
line from side to side of the pinion at the time the motion of the table
is reversed, there is employed, for example, the radial arm, a2, mounted
on the shaft, a3, supporting the driving wheel, a4. The opposite or
vibrating end of the radial arm, a2, supports in suitable bearings the
pinion, a1, and wheel, a5, driving the rack through the medium of the
driving wheel, a4, the effect of which is that through the mechanical
action of the vibrating arm, a2, and pinion, a1 in conjunction with the
vibrating movement of the rack, A, an easy, uniform, and silent motion
is transmitted to the rack and table.



       *       *       *       *       *


A correspondent of the _Tribune_ describes at length the mining camps
about Lake Valley, New Mexico, hitherto thought likely to be the central
camp of that region, and then graphically tells the story of the recent
"rush" to the Perche district. Within a month of the first strike of
silver ore the country was swarming with prospectors, and a thousand or
more prospects had been located.

The Perche district is on the eastern flanks of the Mimbres Mountains,
a range which is a part of the Rocky Mountain range, and runs north and
south generally parallel with the Rio Grande, from which it lies about
forty miles to the westward. The northern half of these mountains is
known as the Black Range, and was the center of considerable mining
excitement a year and a half ago. It is there that the Ivanhoe is
located, of which Colonel Gillette was manager, and in which Robert
Ingersoll and Senator Plumb, of Kansas, were interested, much to the
disadvantage of the former. A new company has been organized, however,
with Colonel Ingersoll as president, and the reopening of work on the
Ivanhoe will probably prove a stimulus to the whole Black Range. From
this region the Perche district is from forty to sixty miles south. It
is about twenty-five miles northwest of Lake Valley, and ten miles west
of Hillsboro, a promising little mining town, with some mills and about
300 people. The Perche River has three forks coming down from the
mountains and uniting at Hillsboro, and it is in the region between
these forks that the recent strikes have been made.

On August 15 "Jack" Shedd, the original discoverer of the Robinson mine
in Colorado, was prospecting on the south branch of the north fork of
the Perche River, when he made the first great strike in the district.
On the summit of a heavily timbered ridge he found some small pieces of
native silver, and then a lump of ore containing very pure silver in the
form of sulphides, weighing 150 pounds, and afterward proved to be worth
on the average $11 a pound. All this was mere float, simply lying on the
surface of the ground. Afterward another block was found, weighing 87
pounds, of horn silver, with specimens nearly 75 per cent. silver. The
strike was kept a secret for a few days. Said a mining man: "I went up
to help bring the big lump down. We took it by a camp of prospectors who
were lying about entirely ignorant of any find. When they saw it they
instantly saddled their horses, galloped off, and I believe they
prospected all night." A like excitement was created when the news of
this and one or two similar finds reached Lake Valley. Next morning
every waiter was gone from the little hotel, and a dozen men had left
the Sierra mines, to try their fortunes at prospecting.

As the news spread men poured into the Perche district from no one knows
where, some armed with only a piece of salt pork, a little meal, and a
prospecting pick; some mounted on mules, others on foot; old men and men
half-crippled were among the number, but all bitten by the monomania
which possesses every prospector. Now there are probably 2,000 men in
the Perche district, and the number of prospects located must far exceed
1,000. Three miners from there with whom I was talking recently owned
forty-seven mines among them, and while one acknowledged that hardly one
prospect in a hundred turns out a prize, the other millionaire in embryo
remarked that he wouldn't take $50,000 for one of his mines. So it goes,
and the victims of the mining fever here seem as deaf to reason as the
buyers of mining stock in New York. Fuel was added to the flame by
the report that Shedd had sold his location, named the Solitaire, to
ex-Governor Tabor and Mr. Wurtzbach on August 25 for $100,000. This was
not true. I met Governor Tabor's representative, who came down recently
to examine the properties, and learned that the Governor had not up to
that date bought the mine. He undoubtedly bonded it, however, and his
representative's opinion of the properties seemed highly favorable.
The Solitaire showed what appeared to be a contact vein, with walls of
porphyry and limestone in a ledge thirty feet wide in places, containing
a high assay of horned silver. The vein was composed of quartz, bearing
sulphides, with horn silver plainly visible, giving an average assay of
from $350 to $500. This was free milling. These were the results shown
simply by surface explorations, which were certainly exceedingly
promising. Recently it has been stated that a little development shows
the vein to be only a blind lead, but the statement lacks confirmation.
In any case the effect of so sensational a discovery is the same in
creating an intense excitement and attracting swarms of prospectors.

But the Perche district does not rest on the Solitaire, for there has
been abundance of mineral wealth discovered throughout its extent. Four
miles south of this prospect, on the middle fork of the Perche, is an
actual mine--the Bullion--which was purchased by four or five Western
mining men for $10,000, and yielded $11,000 in twenty days. The ore
contains horn and native silver. On the same fork are the Iron King and
Andy Johnson, both recently discovered and promising properties, and
there is a valuable mine now in litigation on the south fork of the
Perche, with scores of prospects over the entire district. Now that one
or two sensational strikes have attracted attention, and capital is
developing paying mines, the future of the Perche District seems

       *       *       *       *       *


The _British Medical Journal_ says that Prof. E. Kinch, writing in the
_Agricultural Students' Gazette_, says that the Soy bean approaches more
nearly to animal food than any other known vegetable production, being
singularly rich in fat and in albuminoids. It is largely used as
an article of food in China and Japan. Efforts have been made to
acclimatize it in various parts of the continent of Europe, and fair
success has been achieved in Italy and France; many foods are made from
it and its straw is a useful fodder.

       *       *       *       *       *


[Footnote: Paper read at the British Association, Southampton. Revised
by the Author.--_Nature_.]


Electric lamps on the arc principle are almost as numerous as the trees
in the forest, and it is somewhat fresh to come upon something that is
novel. In these lamps the carbons are consumed as the current flows, and
it is the variation in their consumption which occasions the flickering
and irregularity of the light that is so irritating to the eyes. Special
mechanical contrivances or regulators have to be used to compensate for
this destruction of the carbons, as in the Siemens and Brush type, or
else refractory materials have to be combined with the carbons, as in
the Jablochkoff candle and in the lamp Soleil. The steadiness of the
light depends upon the regularity with which the carbons are moved
toward each other as they are consumed, so as to maintain the electric
resistance between them a constant quantity. Each lamp must have a
certain elasticity of regulation of its own, to prevent irregularities
from the variable material of carbon used, and from variations in the
current itself and in the machinery.

In all electric lamps, except the Brockie, the regulator is in the lamp
itself. In the Brockie system the regulation is automatic, and is made
at certain rapid intervals by the motor engine. This causes a periodic
blinking that is detrimental to this lamp for internal illumination.

[Illustration: FIG. 1. FIG. 2.]

M. Abdank, the inventor of the system which I have the pleasure of
bringing before the Section, separates his regulator from his lamp.
The regulator may be fixed anywhere, within easy inspection and
manipulation, and away from any disturbing influence in the lamp. The
lamp can be fixed in any inaccessible place.

_The Lamp_ (Figs. 1, 2, and 3.)--The bottom or negative carbon is fixed,
but the top or positive carbon is movable, in a vertical line. It is
screwed at the point, C, to a brass rod, T (Fig. 2), which moves freely
inside the tubular iron core of an electromagnet, K. This rod is
clutched and lifted by the soft iron armature, A B, when a current
passes through the coil, M M. The mass of the iron in the armature is
distributed so that the greater portion is at one end, B, much nearer
the pole than the other end. Hence this portion is attracted first, the
armature assumes an inclined position, maintained by a brass button, t,
which prevents any adhesion between the armature and the core of the
electromagnet. The electric connection between the carbon and the coil
of the electromagnet is maintained by the flexible wire, S.

[Illustration: FIG. 3.]

The electromagnet, A (Fig. 1), is fixed to a long and heavy rack, C,
which falls by its own weight and by the weight of the electromagnet and
the carbon fixed to it. The length of the rack is equal to the length of
the two carbons. The fall of the rack is controlled by a friction break,
B (Fig. 3), which acts upon the last of a train of three wheels put
in motion by the above weight. The break, B, is fixed at one end of
a lever, B A, the other end carrying a soft iron armature, F,
easily adjusted by three screws. This armature is attracted by the
electromagnet, E E (whose resistance is 1,200 ohms), whenever a current
circulates through it. The length of the play is regulated by the screw,
V. The spring, L, applies tension to the break.

_The Regulator_.--This consists of a balance and a cut-off.

_The Balance_ (Figs. 4 and 5) is made with two solenoids. S and S',
whose relative resistances is adjustable. S conveys the main current,
and is wound with thick wire having practically no resistance, and S'
is traversed by a shunt current, and is wound with fine wire having a
resistance of 600 ohms. In the axes of these two coils a small and light
iron tube (2 mm. diameter and 60 mm. length) freely moves in a vertical
line between two guides. When magnetized it has one pole in the middle
and the other at each end. The upward motion is controlled by the
spring, N T. The spring rests upon the screw, H, with which it makes
contact by platinum electrodes. This contact is broken whenever the
little iron rod strikes the spring, N T.

The positive lead from the dynamo is attached to the terminal, B, then
passes through the coil, S, to the terminal, B', whence it proceeds to
the lamp. The negative lead is attached to terminal, A, passing directly
to the other terminal, A', and thence to the lamp.

[Illustration: FIG. 4]

The shunt which passes through the fine coil, S', commences at the
point, P. The other end is fixed to the screw, H, whence it has two
paths, the one offering no resistance through the spring, T N, to the
upper negative terminal, A'; the other through the terminal, J, to the
electromagnet of the break, M, and thence to the negative terminal of
the lamp, L'.

[Illustration: FIG. 5.]

_The Cut-off_.--The last part of the apparatus (Fig. 4) to be described
is the cut-off, which is used when there are several lamps in series. It
is brought into play by the switch, C D, which can be placed at E or D.
When it is at E, the negative terminal, A, is in communication with
the positive terminal, B, through the resistance, R, which equals the
resistance of the lamp, which is, therefore, out of circuit. When it is
at D the cut-off acts automatically to do the same thing when required.
This is done by a solenoid, V, which has two coils, the one of thick
wire offering no resistance, and the other of 2,000 ohms resistance. The
fine wire connects the terminals, A' and B. The solenoid has a movable
soft iron core suspended by the spring, U. It has a cross-piece of iron
which can dip into two mercury cups, G and K, when the core is sucked
into the solenoid. When this is the case, which happens when any
accident occurs to the lamp, the terminal, A, is placed in connection
with the terminal, B, through the thick wire of V and the resistance, R,
in the same way as it was done by the switch, C D.

_Electrical Arrangement_.--The mode in which several lamps are connected
up in series is shown by Fig. 6. M is the dynamo machine. The + lead is
connected to B1 of the balance it then passes to the lamp, L, returning
to the balance, and then proceeds to each other lamp, returning finally
to the negative pole of the machine. When the current enters the balance
it passes through the coil, S, magnetizing the iron core and drawing
it downward (Fig. 4). It then passes to the lamp, L L', through the
carbons, then returns to the balance, and proceeds back to the negative
terminal of the machine. A small portion of the current is shunted off
at the point, P, passing through the coil, S', through the contact
spring, T N, to the terminal, A', and drawing the iron core in
opposition to S. The carbons are in contact, but in passing through
the lamp the current magnetizes the electromagnet, M (Fig. 2), which
attracts the armature, A B, that bites and lifts up the rod, T, with the
upper carbon, a definite and fixed distance that is easily regulated
by the screws, Y Y. The arc then is formed, and will continue to burn
steadily as long as the current remains constant. But the moment the
current falls, due to the increased resistance of the arc, a greater
proportion passes through the shunt, S' (Fig. 4), increasing its
magnetic moment on the iron core, while that of S is diminishing. The
result is that a moment arrives when equilibrium is destroyed, the iron
rod strikes smartly and sharply upon the spring, N T. Contact between T
and H is broken, and the current passes through the electromagnet of the
break in the lamp. The break is released for an instant, the carbons
approach each other. But the same rupture of contact introduces in the
shunt a new resistance of considerable magnitude (viz., 1,200 ohms),
that of the electromagnets of the break. Then the strength of the shunt
current diminishes considerably, and the solenoid, S, recovers briskly
its drawing power upon the rod, and contact is restored. The carbons
approach during these periods only about 0.01 to 0.02 millimeter.
If this is not sufficient to restore equilibrium it is repeated
continually, until equilibrium is obtained. The result is that the
carbon is continually falling by a motion invisible to the eye, but
sufficient to provide for the consumption of the carbons.

[Illustration: FIG. 6]

The contact between N T and H is never completely broken, the sparks are
very feeble, and the contacts do not oxidize. The resistances inserted
are so considerable that heating cannot occur, while the portion of the
current abstracted for the control is so small that it may be neglected.

The balance acts precisely like the key of a Morse machine, and the
break precisely like the sounder-receiver so well known in telegraphy.
It emits the same kind of sounds, and acts automatically like a skilled
and faithful telegraphist.

This regulation, by very small and short successive steps, offers
several advantages: (1) it is imperceptible to the eye; (2) it does not
affect the main current; (3) any sudden instantaneous variation of the
main current does not allow a too near approach of the carbon points.
Let, now, an accident occur; for instance, a carbon is broken. At once
the automatic cut-off acts, the current passes through the resistance,
R, instead of passing through the lamp. The current through the fine
coil is suddenly increased, the rod is drawn in, contact is made at G
and K, and the current is sent through the coil, R. As soon as contact
is again made by the carbons, the current in the coil, S, is increased,
that of the thick wire in V diminished, and the antagonistic spring,
U, breaks the contact at G and K. The rupture of the light is almost
invisible, because the relighting is so brisk and sharp.

I have seen this lamp in action, and its constant steadiness leaves
nothing to be desired.

       *       *       *       *       *


Our readers are well aware that water as found naturally is never
absolutely free from dissolved impurities; and in ordinary cases it
contains solid impurities derived both from the inorganic and organic
kingdoms, together with gaseous substances; these latter being generally
derived from the atmosphere.

By far the purest water which occurs in nature is rain-water, and if
this be collected in a secluded district, and after the air has been
well washed by previous rain, its purity is remarkable; the extraneous
matter consisting of little else than a trace of carbonic acid and other
gases dissolved from the air. In fact, such water is far purer than any
distilled water to be obtained in commerce. The case is very different
when the rain-water is collected in a town or densely populated
district, more especially if the water has been allowed to flow over
dirty roofs. The black and foully-smelling liquid popularly known as
soft water is so rich in carbonaceous and organic constituents as to be
of very limited use to the photographer; but by taking the precaution of
fitting up a simple automatic shunt for diverting the stream until the
roofs have been thoroughly washed, it becomes possible to insure a good
supply of clean and serviceable soft water, even in London. Several
forms of shunt have been devised, some of these being so complex as
to offer every prospect of speedy disorganization; but a simple and
efficient apparatus is figured in _Engineering_ by a correspondent who
signs himself "Millwright," and as we have thoroughly proved the value
of an apparatus which is practically identical, we reproduce the
substance of his communication.

A gentleman of Newcastle, a retired banker, having tried various filters
to purify the rain-water collected on the roof of his house, at length
had the idea to allow no water to run into the cistern until the roof
had been well washed. After first putting up a hard-worked valve, the
arrangement as sketched below has been hit upon. Now Newcastle is a very
smoky place, and yet my friend gets water as pure as gin, and almost
absolutely free from any smack of soot.


The sketch explains itself. The weight, W, and the angle of the lever,
L, are such, that when the valve, V, is once opened it goes full open. A
small hole in the can C, acts like a cataract, and brings matters to a
normal state very soon after the rain ceases.

The proper action of the apparatus can only be insured by a careful
adjustment of the weight, W, the angle through which the valve opens,
and the magnitude of the vessel, C. It is an advantage to make
the vessel, C, somewhat broader in proportion to its height than
represented, and to provide it with a movable strainer placed about half
way down. This tends to protect the cataract hole, and any accumulation
of leaves and dirt can be removed once in six months or so. Clean soft
water is valuable to the photographer in very many cases. Iron developer
(wet plate) free from chlorides will ordinarily remain effective on the
plate much longer than when chlorides are present, and the pyrogallic
solution for dry-plate work will keep good for along time if made with
soft water, while the lime which is present in hard water causes the
pyrogallic acid to oxidize with considerable rapidity. Negatives that
have been developed with oxalate developer often become covered with a
very unsightly veil of calcium oxalate when rinsed with hard water, and
something of a similar character occasionally occurs in the case of
silver prints which are transferred directly from the exposure frame to
impure water.

To the carbon printer clean rain-water is of considerable value, as he
can develop much more rapidly with soft water than with hard water;
or, what comes to the same thing, he can dissolve away his superfluous
gelatine at a lower temperature than would otherwise be necessary.

The cleanest rain-water which can ordinarily be collected in a town is
not sufficiently pure to be used with advantage in the preparation of
the nitrate bath, it being advisable to use the purest distilled water
for this purpose; and in many cases it is well to carefully distill
water for the bath in a glass apparatus of the kind figured below.


A, thin glass flask serving as a retort. The tube, T, is fitted
air-tight to the flask by a cork, C.

B, receiver into which the tube, T, fits quite loosely.

D, water vessel intended to keep the spiral of lamp wick, which is shown
as surrounding T, in a moist condition. This wick acts as a siphon, and
water is gradually drawn over into the lower receptacle, E.

L, spirit lamp, which may, in many cases, be advantageously replaced by
a Bunsen burner.

A small metal still, provided with a tin condensing worm, is, however, a
more generally serviceable arrangement, and if ordinary precautions are
taken to make sure that the worm tube is clean, the resulting distilled
water will be nearly as pure as that distilled in glass vessels.

Such a still as that figured below can be heated conveniently over an
ordinary kitchen fire, and should find a place among the appliances
of every photographer. Distilled water should always be used in the
preparation of emulsion, as the impurities of ordinary water may often
introduce disturbing conditions.--_Photographic News_.


       *       *       *       *       *



The author refers to the customary view that black phosphorus is
merely a mixture of the ordinary phosphorus with traces of a metallic
phosphide, and contends that this explanation is not in all cases
admissible. A specimen of black or rather dark gray phosphorus, which
the author submitted to the Academy, became white if melted and remained
white if suddenly cooled, but if allowed to enter into a state of
superfusion it became again black on contact with either white or black
phosphorus. A portion of the black specimen being dissolved in carbon
disulphide there remained undissolved merely a trace of a very pale
yellow matter which seemed to be amorphous phosphorus.--_Comptes

       *       *       *       *       *


According to M. C. Leeuw, water in which malt has been steeped has the
following composition:

    Organic matter.        0.56 per cent.
    Mineral matter.        0.52    "
    Total dry matter.      1.08    "
    Nitrogen.             0.033    "

The mineral matter consists of--

    Potash.               0.193    "
    Phosphoric acid.      0.031    "
    Lime.                 0.012    "
    Soda.                 0.047    "
    Magnesia.             0.016    "
    Sulphuric acid.       0.007    "
    Oxide of iron.        traces.
    Chlorine and silica.  0.212    "

       *       *       *       *       *


We give opposite illustrations of Schreiber's apparatus for revivifying
bone-black or animal charcoal. The object of revivification is to render
the black fit to be used again after it has lost its decolorizing
properties through service--that is to say, to free its pores from the
absorbed salts and insoluble compounds that have formed therein
during the operation of sugar refining. There are two methods
employed--fermentation and washing. At present the tendency is to
abandon the former in order to proceed with as small a stock of black as
possible, and to adopt the method of washing with water and acid in a
rotary washer.

Figs. 1 and 2 represent a plan and elevation of a bone-black room,
containing light filters, A, arranged in a circle around wells, B. These
latter have the form of a prism with trapezoidal base, whose small sides
end at the same point, d, and the large ones at the filter. The funnel,
E, of the washer, F, is placed in the space left by the small ends of
the wells, so that the black may be taken from these latter and thrown
directly into the washer. The washer is arranged so that the black may
flow out near the steam fitter, G, beneath the floor. The discharge of
this filter is toward the side of the elevator, H, which takes in the
wet black below, and carries it up and pours it into the drier situated
at the upper part of the furnace. This elevator, Figs. 3 and 4, is
formed of two vertical wooden uprights, A, ten centimeters in thickness,
to which are fixed two round-iron bars the same as guides. The lift,
properly so-called, consists of an iron frame, C, provided at the four
angles with rollers, D, and supporting a swinging bucket, E, which, on
its arrival at the upper part of the furnace, allows the black to fall
to an inclined plane that leads it to the upper part of the drier. The
left is raised and lowered by means of a pitch-chain, F, fixed to the
middle of the frame, C, and passing over two pulleys, G, at the upper
part of the frame and descending to the mechanism that actuates it.
This latter comprises a nut, I, acting directly on the chain; a toothed
wheel, K, and a pinion, J, gearing with the latter and keyed upon the
shaft of the pulleys, L and M. The diameter of the toothed wheel, K, is
0.295 of a meter, and it makes 53.4 revolutions per minute. The diameter
of the pinion is 0.197 of a meter, and it makes 80 revolutions per
minute. The pulleys, M and L, are 0.31 of a meter in diameter, and
make 80 revolutions per minute. Motion is transmitted to them by other
pulleys, N, keyed upon a shaft placed at the lower part, which receives
its motion from the engine of the establishment through the intermedium
of the pulley, O. The diameter of the latter is 0.385 of a meter, and
that of N is 0.58. They each make 43 revolutions per minute.






The elevator is set in motion by the simple maneuver of the gearing
lever, P, and when this has been done all the other motions are effected

_The Animal Black Furnace_.--This consists of a masonry casing of
rectangular form, in which are arranged on each side of the same
fire-place two rows of cast-iron retorts, D, of undulating form, each
composed of three parts, set one within the other. These retorts, which
serve for the revivification of the black, are incased in superposed
blocks of refractory clay, P, Q, S, designed to regularize the
transmission of heat and to prevent burning. These pieces are kept in
their respective places by crosspieces, R. The space between the retorts
occupied by the fire-place, Y, is covered with a cylindrical dome, O, of
refractory tiles, forming a fire-chamber with the inner surface of the
blocks, P, Q, and S. The front of the surface consists of a cast-iron
plate, containing the doors to the fire-place and ash pan, and a larger
one to allow of entrance to the interior to make repairs.

One of the principal disadvantages of furnaces for revivifying animal
charcoal has been that they possessed no automatic drier for drying the
black on its exit from the washer. It was for the purpose of remedying
this that Mr. Schreiber was led to invent the automatic system of drying
shown at the upper part of the furnace, and which is formed of two
pipes, B, of undulating form, like the retorts, with openings throughout
their length for the escape of steam. Between these pipes there is a
closed space into which enters the waste heat and products of combustion
from the furnace. These latter afterward escape through the chimney at
the upper part.

In order that the black may be put in bags on issuing from the furnace,
it must be cooled as much as possible. For this purpose there are
arranged on each side of the furnace two pieces of cast iron tubes, F,
of rectangular section, forming a prolongation of the retorts and making
with them an angle of about 45 degrees. The extremities of these tubes
terminate in hollow rotary cylinders, G, which permit of regulating the
flow of the black into a car, J (Fig. 1), running on rails.

From what precedes, it will be readily understood how a furnace is run
on this plan.

The bone-black in the hopper, A, descends into the drier, B, enters the
retorts, D, and, after revivification, passes into the cooling pipes, F,
from whence it issues cold and ready to be bagged. A coke fire having
been built in the fire-place, Y, the flames spread throughout the fire
chamber, direct themselves toward the bottom, divide into two parts to
the right and left, and heat the back of the retorts in passing. Then
the two currents mount through the lateral flues, V, and unite so as to
form but one in the drier. Within the latter there are arranged plates
designed to break the current from the flames, and allow it to heat all
the inner parts of the pipes, while the apertures in the drier allow of
the escape of the steam.

By turning one of the cylinders, G, so as to present its aperture
opposite that of the cooler, it instantly fills up with black. At this
moment the whole column, from top to bottom, is set in motion. The
bone-black, in passing through the undulations, is thrown alternately to
the right and left until it finally reaches the coolers. This operation
is repeated as many times as the cylinder is filled during the descent
of one whole column, that is to say, about forty times.

With an apparatus of the dimensions here described, 120 hectoliters
of bone-black may be revivified in twenty four hours, with 360 to 400
kilogrammes of coke.--_Annales Industrielles_.

       *       *       *       *       *

[Continued from SUPPLEMENT, No. 330, page 5264.]


In our last article, under the above heading, the advantages to be
gained by the use of potash soap as compared with soda soap were pointed
out, and the reasons of this superiority, especially in the case of
washing wool or woolen fabrics, were pretty fully gone into. It was also
further explained why the potash soaps generally sold to the public were
unfit for general use, owing to their not being neutral--that is to say,
containing a considerable excess of free or unsaponified alkali, which
acts injuriously on the fiber of any textile material, and causes sore
hands if used for household or laundry purposes. It was shown that the
cause of this defect was owing to the old-fashioned method of making
potash or soft soap, by boiling with wood ashes or other impure form of
potash; but that a perfectly pure and neutral potash soap could readily
be made with pure caustic potash, which within the last few years has
become a commercial article, manufactured on a large scale; just in
the same manner as the powdered 98 per cent. caustic soda, which was
recommended in our previous articles on making hard soap without

The process of making pure neutral potash soap is very simple, and
almost identical with that for making hard soap with pure powdered
caustic soda. The following directions, if carefully and exactly
followed, will produce a first-class potash soap, suitable either for
the woolen manufacturer for washing his wool, and the cloth afterward
made from it, or for household and laundry purposes, for which uses it
will be found far superior to any soda soap, no matter how pure or well
made it may be.

Dissolve twenty pounds of pure caustic potash in two gallons of water.
Pure caustic potash is very soluble, and dissolves almost immediately,
heating the water. Let the lye thus made cool until warm to the
hand--say about 90 F. Melt eighty pounds of tallow or grease, which must
be free from salt, and let it cool until fairly hot to the hand--say
130 F.; or eighty pounds of any vegetable or animal oil may be taken
instead. Now pour the caustic potash lye into the melted tallow or oil,
stirring with a flat wooden stirrer about three inches broad, until both
are thoroughly mixed and smooth in appearance. This mixing may be done
in the boiler used to melt the tallow, or in a tub, or half an oil
barrel makes a good mixing vessel. Wrap the tub or barrel well up in
blankets or sheepskins, and put away for a week in some warm dry place,
during which the mixture slowly turns into soap, giving a produce of
about 120 pounds of excellent potash soap. If this soap is made with
tallow or grease it will be nearly as hard as soda soap. When made by
farmers or householders tallow or grease will generally be taken, as it
is the cheapest, and ready to hand on the spot. For manufacturers, or
for making laundry soap, nothing could be better than cotton seed oil. A
magnificent soap can be made with this article, lathering very freely.
When made with oil it is better to remelt in a kettle the potash soap,
made according to the above directions, with half its weight of water,
using very little heat, stirring constantly, and removing the fire as
soon as the water is mixed with and taken up by the soap. A beautifully
bright soap is obtained in this way, and curiously the soap is actually
made much harder and stiffer by this addition of water than when it is
in a more concentrated state previously to the water being added.

With reference to the caustic potash for making the soap, it can be
obtained in all sizes of drums, but small packages just sufficient for
a batch of soap are generally more economical than larger packages, as
pure caustic potash melts and deteriorates very quickly when exposed
to the air. The Greenbank Alkali Co., of St. Helens, seems to have
appreciated this, and put upon the market pure caustic potash in twenty
pound canisters, which are very convenient for potash soft soap making
by consumers for their own use.

While on this subject of caustic potash, it cannot be too often repeated
that _caustic potash_ is a totally different article to _caustic soda_,
though just like it in appearance, and therefore often sold as such.
One of the most barefaced instances of this is the so-called "crystal
potash," "ball potash," or "rock potash," of the lye packers, sold in
one pound packages, which absolutely, without exception, do not contain
a single grain of potash, but simply consist of caustic soda more or
less adulterated--as a rule very much "more" than "less!" It is much
to be regretted that this fraud on the public has been so extensively
practiced, as potash has been greatly discredited by this procedure.

The subject of fleece scouring or washing the wool while growing on
the sheep, with a potash soap made on the spot with the waste tallow
generally to be had on every sheep farm, seems recently to have been
attracting attention in some quarters, and certainly would be a source
of profit to sheep owners by putting their wool on the market in the
best condition, and at the same time cleaning the skin of the sheep. It
therefore appears to be a move in the right direction.

In concluding this series of articles on practical soap making from a
consumer's point of view, the writer hopes that, although the subject
has been somewhat imperfectly handled, owing to necessarily limited
space and with many unavoidable interruptions, yet that they may have
been found of some interest and assistance to consumers of soap who
desire easily and readily to make a pure and unadulterated article for
their own use.

       *       *       *       *       *



Having had occasion during the last six years to manufacture lead
plaster in considerable quantities, it occurred to me that cotton seed
oil might be used instead of olive oil, at less expense, and with as
good results. The making of this plaster with cotton seed oil has been
questioned, as, according to some authorities, the product is not of
good consistence, and is apt to be soft, sticky, and dark colored;
but in my experience such is not the case. If the U. S. P. process is
followed in making this plaster, substituting for the olive oil cotton
seed oil, and instead of one half-pint of boiling water one and one-half
pint are added, the product obtained will be equally as good as that
from olive oil. My results with this oil in making lead plaster led me
to try it in making the different liniments of the Pharmacopoeia, with
the following results:

_Linimentum Ammoniæ_.--This liniment, made with cotton seed oil, is of
much better consistency than when made with olive oil. It is not so
thick, will pour easily out of the bottle, and if the ammonia used is of
proper strength, will make a perfect liniment.

_Linimentum Calcis_.--Cotton seed oil is not at all adapted to making
this liniment. It does not readily saponify, separates quickly, and it
is almost impossible to unite when separated.

_Linimentum Camphoræ_.--Cotton seed oil is far superior to olive oil in
making this liniment, it being a much better solvent of camphor. It has
not that disagreeable odor so commonly found in the liniment.

_Linimentum Chloroformi_.--Cotton seed oil being very soluble in
chloroform, the liniment made with it leaves nothing to be desired.

_Linimentum Plumbi Subacetatis_.--When liq. plumbi subacet. is mixed
with cotton seed oil and allowed to stand for some time the oil assumes
a reddish color similar to that of freshly made tincture of myrrh. When
the liquor is mixed with olive oil, if the oil be pure, no such change
takes place. Noticing this change, it occurred to me that this would be
a simple and easy way to detect cotton seed oil when mixed with olive
oil. This change usually takes place after standing from twelve to
twenty-four hours. It is easily detected in mixtures containing five
per cent., or even less, of the oils, and I am convinced, after making
numerous experiments with different oils, that it is peculiar to cotton
seed oil.--_American Journal of Pharmacy_.

       *       *       *       *       *


[Footnote: From a lecture delivered at the Sanitary Congress, at
Newcastle-on-Tyne, September 28, 1882.]


Although eating cannot be said to be in any way a new fashion, it has
nevertheless been reserved for modern times, and indeed we may say the
present generation, to get a fairly clear idea of the way in which
food is really utilized for the work of our bodily frame. We must not,
however, plume ourselves too much upon our superior knowledge, for
inklings of the truth, more or less dim, have been had through all ages,
and we are now stepping into the inheritance of times gone by, using the
long and painful experience of our predecessors as the stepping-stone
to our more accurate knowledge of the present time. In this, as in many
other things, we are to some extent in the position of a dwarf on the
shoulders of a giant; the dwarf may, indeed, see further than the giant;
but he remains a dwarf, and the giant a giant.

The question has been much discussed as to what the original food of man
was, and some people have made it a subject of excited contention. The
most reasonable conclusion is that man is naturally a frugivorous or
fruit-eating animal, like his cousins the monkeys, whom he still so
much resembles. This forms a further argument in favor of his being
originated in warm regions, where fruits of all kinds were plentiful. It
is pretty clear that the resort to animal food, whether the result of
the pressure of want from failure of vegetable products, or a mere taste
and a desire for change and more appetizing food, is one that took place
many ages ago, probably in the earliest anthropoid, if not in the latest
pithecoid stage. No doubt some advantage was recognized in the more
rapid digestion and the comparative ease with which the hunter or fisher
could obtain food, instead of waiting for the ripening of fruits in
countries which had more or less prolonged periods of cold and inclement
weather. Some anatomical changes have doubtless resulted from the
practice, but they are not of sufficiently marked character to found
much argument upon; all that we can say being that the digestive
apparatus in man seems well adapted for digesting any food that is
capable of yielding nutriment, and that even when an entire change is
made in the mode of feeding, the adaptability of the human system
shows itself in a more or less rapid accommodation to the altered

Food, then, is any substance which can be taken into the body and
applied to use, either in building up or repairing the tissues and
framework of the body itself, or in providing energy and producing
animal heat, or any substance which, without performing those functions
directly, controls, directs, or assists their performance. With this
wide definition it is evident that we include all the ordinary articles
recognized commonly as food, and that we reject all substances
recognized commonly as poisons. But it will also include such substances
as water and air, both of which are essential for nutrition, but are not
usually recognized as belonging to the list of food substances in the
ordinary sense. When we carry our investigation further, we find that
the organic substances may be again divided into two distinct classes,
namely, that which contains nitrogen (the casein), and those that do not
(the butter and sugar).

On ascertaining this, we are immediately struck with the remarkable fact
that all the tissues and fluids of the body, muscles (or flesh),
bone, blood--all, in short, except the fat--contain nitrogen, and,
consequently, for their building up in the young, and for their repair
and renewal in the adult, nitrogen is absolutely required. We therefore
reasonably infer that the nitrogenous substance is necessary for this
purpose. Experiment has borne this out, for men who have been compelled
to live without nitrogenous food by dire necessity, and criminals on
whom the experiment has been tried, have all perished sooner or later in
consequence. When nitrogenous substances are used in the body, they
are, of course, broken up and oxidized, or perhaps we ought to say more
accurately, they take the place of the tissues of the body which wear
away and are carried off by oxidation and other chemical changes.

Now, modern science tell us that such changes are accompanied with
manifestations of energy in some form or other, most frequently in
that of heat, and we must look, therefore, upon nitrogenous food
as contributing to the energy of the body in addition to its other

What are the substances which we may class as nitrogenous. In the first
place, we have the typical example of the purest form in _albumin_,
or white of egg; and from this the name is now given to the class of
_albuminates_. The animal albuminates are: Albumin from eggs, fibrin
from muscles, or flesh, myosin, or synronin, also from animals, casein
(or cheesy matter) from milk, and the nitrogenous substances from blood.
In the vegetable kingdom, we have glutin, or vegetable fibrin, which is
the nourishing constituent of wheat, barley, oats, etc.; and legumin,
or vegetable casein, which is the peculiar substance found in peas and
beans. The other organic constituents--viz., the fats and the starches
and sugars--contain no nitrogen, and were at one time thought to be
concerned in producing animal heat.

We now know--thanks to the labors of Joule, Lyon Playfair, Clausius,
Tyndall, Helmholtz, etc.--that heat itself is a mode of motion, a form
of convertible energy, which can be made to do useful or productive
work, and be expressed in terms of actual work done. Modern experiment
shows that all our energy is derived from that of food, and, in
particular from the non-nitrogenous part of it, that is, the fat,
starch, and sugar. The nutrition of man is best maintained when he is
provided with a due admixture of all the four classes of aliment which
we have mentioned, and not only that, but he is also better off if he
has a variety of each class. Thus he may and ought to have albumen,
fibrine, gluten, and casein among the albuminates, or at least two of
them; butter and lard, or suet, or oil among the fats; starch of wheat,
potato, rice, peas, etc., and cane-sugar, and milk-sugar among the
carbo-hydrates. The salts cannot be replaced, so far as we know. Life
may be maintained in fair vigor for some time on albuminates only, but
this is done at the expense of the tissues, especially the fat of the
body, and the end must soon come; with fat and carbo hydrates alone
vigor may also be maintained for some time, at the expense of the
tissues also, but the limit is a near one, In either of these cases we
suppose sufficient water and salts to be provided.

We must now inquire into the quantities of food necessary; and this
necessitates a little consideration of the way in which the work of
the body is carried on. We must look upon the human body exactly as a
machine; like an engine with which we are all so familiar. A certain
amount of work requires to be done, say, a certain number of miles of
distance to be traversed; we know that to do this a certain number of
pounds, or hundredweights, or tons of coal must be put into the fire of
the boiler in order to furnish the requisite amount of energy through
the medium of steam. This amount of fuel must bear a certain proportion
to the work, and also to the velocity with which it is done, so both
quantity and time have to be accounted for.

No lecture on diet would be complete without a reference to the vexed
question of alcohol. I am no teetotal advocate, and I repudiate the
rubbish too often spouted from teetotal platforms, talk that is,
perhaps, inseparable from the advocacy of a cause that imports a good
deal of enthusiasm. I am at one, however, in recognizing the evils of
excess, and would gladly hail their diminution. But I believe that
alcohol properly used may be a comfort and a blessing, just as I know
that improperly used it becomes a bane and a curse. But we are now
concerned with it as an article of diet in relation to useful work, and
it may be well to call attention markedly to the fact that its use in
this way is very limited. The experiments of the late Dr. Parkes, made
in our laboratory, at Netley, were conclusive on the point, that beyond
an amount that would be represented by about one and a half to two pints
of beer, alcohol no longer provided any convertible energy, and that,
therefore, to take it in the belief that it did do so is an error.
It may give a momentary stimulus in considerable doses, but this is
invariably followed by a corresponding depression, and it is a maxim now
generally followed, especially on service, never to give it before or
during work. There are, of course, some persons who are better without
it altogether, and so all moderation ought to be commended, if not

There are other beverages which are more useful than the alcoholic,
as restoratives, and for support in fatigue. Tea and coffee are
particularly good. Another excellent restorative is a weak solution
of Liebig's extract of meat, which has a remarkable power of removing
fatigue. Perhaps one of the most useful and most easily obtainable is
weak oatmeal gruel, either hot or cold. With regard to tobacco, it also
has some value in lessening fatigue in those who are able to take it,
but it may easily be carried to excess. Of it we may say, as of alcohol,
that in moderation it seems harmless, and even useful to some extent,
but, in excess, it is rank poison.

There is one other point which I must refer to, and which is especially
interesting to a great seaport like this. This is the question of
scurvy--a question of vital importance to a maritime nation. A paper
lately issued by Mr. Thomas Gray, of the Board of Trade, discloses the
regrettable fact that since 1873 there has been a serious falling off,
the outbreaks of scurvy having again increased until they reached
ninety-nine in 1881. This, Mr. Gray seems to think, is due to a neglect
of varied food scales; but it may also very probably have arisen from
the neglect of the regulation about lime-juice, either as to issue or
quality, or both. But it is also a fact of very great importance that
mere monotony of diet has a most serious effect upon health; variety
of food is not merely a pandering to gourmandism or greed, but a real
sanitary benefit, aiding digestion and assimilation. Our Board of Trade
has nothing to do with the food scales of ships, but Mr. Gray hints that
the Legislature will have to interfere unless shipowners look to it
themselves. The ease with which preserved foods of all kinds can be
obtained and carried now removes the last shadow of an excuse for
backwardness in this matter, and in particular the provision of a large
supply of potatoes, both fresh and dried, ought to be an unceasing care;
this is done on board American ships, and to this is doubtless owing in
a great part the healthiness of their crews. Scurvy in the present
day is a disgrace to shipowners and masters; and if public opinion is
insufficient to protect the seamen, the legislature will undoubtedly
step in and do so.

And now let me close by pointing out that the study of this commonplace
matter of eating and drinking opens out to us the conception of the
grand unity of nature; since we see that the body of man differs in no
way essentially from other natural combinations, but is subject to
the same universal physical laws, in which there is no blindness, no
variableness, no mere chance, and disobedience of which is followed as
surely by retribution as even the keenest eschatologist might desire.

       *       *       *       *       *



Some time since, in a paper to which I am unfortunately unable to refer,
a French chemist affirmed that the poisonous principle in snakes, or
eliminated by snakes, was of the nature of an alkaloid, and gave a name
to this class of bodies.

Mr. Pedler has shown that snake poison is destroyed or neutralized
by means of platinic chloride, owing probably to the formation of an
insoluble double platinic chloride, such as is formed with almost if not
all alkaloids.

In this country (Texas) where rattlesnakes are very common, and persons
camping out much exposed to their bites, a very favorite anecdote, or
_remedia_ as the Mexicans cull it, is a strong solution of iodine in
potassium iodide.[1]

[Footnote 1: The solution is applied as soon as possible to the wound,
preferably enlarged, and a few drops taken internally. The common
Mexican _remedia_ is the root of the _Agave virginica_ mashed or chewed
and applied to the wound, while part is swallowed.

Great faith is placed in this root by all residents here, who are seldom
I without it, but, I have had no experience of it myself; and the
internal administration is no doubt useless.

Even the wild birds know of this root; the queer paisano (? ground
woodpecker) which eats snakes, when wounded by a _vibora de cascabel_,
runs into woods, digs up and eats a root of the agave, just like the
mongoose; but more than that, goes back, polishes off his enemy, and
eats him. This has been told me by Mexicans who, it may be remarked, are
not _always_ reliable.]

I have had occasion to prove the efficacy of this mixture in two cases
of _cascabel_ bites, one on a buck, the other on a dog; and it occurred
to me that the same explanation of its action might be given as above
for the platinum salt, viz., the formation of an insoluble iodo compound
as with ordinary alkaloids if the snake poison really belongs to this

Having last evening killed a moderate sized rattlesnake--_Crotalus
horridus_--which had not bitten anything, I found the gland fully
charged with the white opaque poison; on adding iodine solution to a
drop of this a dense light-brown precipitate was immediately formed,
quite similar to that obtained with most alkaloids, exhibiting under the
microscope no crystalline structure.

In the absence of iodine a good extemporaneous solution for testing
alkaloids, and perhaps a snake poison antidote, may be made by adding a
few drops of ferric chloride to solution of potassium of iodide; this
is a very convenient test agent which I used in my laboratory for many

Although rattlesnake poison could be obtained here in very considerable
quantity, it is out of my power to make such experiments as I could
desire, being without any chemical appliances and living a hundred miles
or more from any laboratory. The same may be said with regard to books,
and possibly the above iodine reaction has been already described.

Dr. Richards states that the cobra poison is destroyed by potassium
permanganate; but this is no argument in favor of that salt as an
antidote. Mr. Pedler also refers to it, but allows that it would not be
probably of any use after the poison had been absorbed. Of this I
think there can be no doubt, remembering the easy decomposition of
permanganate by most organic substances, and I cannot but think that the
medicinal or therapeutic advantages of that salt, taken internally, are
equally problematical, unless the action is supposed to take place in
the stomach.

In the bladder of the same rattlesnake I found a considerable
quantity of light-brown amorphous ammonium urate, the urine pale
yellow.--_Chemical News_.

Hermanitas Ranch, Texas.

       *       *       *       *       *


[Footnote: Dr. D. J. Macgowan, in Medical Reports of China. 1881.]

Two writers in _Nature_, both having for their theme "Skin-furrows on
the Hand," solicit information on the subject from China.[1] As the
subject is considered to have a bearing on medical jurisprudence and
ethnology as well, this report is a suitable vehicle for responding to
the demand.

[Footnote 1: Henry Faulds, Tzukiyi Hospital, Tokio, Japan. W. J.
Herschel, Oxford, England.--_Nature_, 28th October and 25th November,

Dr. Faulds' observations on the finger-tips of the Japanese have an
ethnic bearing and relate to the subject of heredity. Mr. Herschel
considers the subject as an agent of Government, he having charge for
twenty years of registration offices in India, where he employed finger
marks as sign manuals, the object being to prevent personation and
repudiation. Doolittle, in his "Social Life of the Chinese," describes
the custom. I cannot now refer to native works where the practice of
employing digital rugæ as a sign manual is alluded to. I doubt if its
employment in the courts is of ancient date. Well-informed natives think
that it came into vogue subsequent to the Han period; if so, it is in
Egypt that earliest evidence of the practice is to be found. Just as the
Chinese courts now require criminals to sign confessions by impressing
thereto the whorls of their thumb-tips--the right thumb in the case of
women, the left in the case of men--so the ancient Egyptians, it
is represented, required confessions to be sealed with their
thumbnails--most likely the tip of the digit, as in China. Great
importance is attached in the courts to this digital form of signature,
"finger form." Without a confession no criminal can be legally executed,
and the confession to be valid must be attested by the thumb-print
of the prisoner. No direct coercion is employed to secure this; a
contumacious culprit may, however, be tortured until he performs the
act which is a prerequisite to his execution. Digital signatures are
sometimes required in the army to prevent personation; the general
in command at Wenchow enforces it on all his troops. A document thus
attested can no more be forged or repudiated than a photograph--not so
easily, for while the period of half a lifetime effects great changes
in the physiognomy, the rugæ of the fingers present the same appearance
from the cradle to the grave; time writes no wrinkles there. In the
army everywhere, when the description of a person is written down, the
relative number of volutes and coniferous finger-tips is noted. It
is called taking the "whelk striæ," the fusiform being called "rice
baskets," and the volutes "peck measures." A person unable to write, the
form of signature which defies personation or repudiation is required in
certain domestic cases, as in the sale of children or women. Often when
a child is sold the parents affix their finger marks to the bill of
sale; when a husband puts away his wife, giving her a bill of divorce,
he marks the document with his entire palm; and when a wife is sold, the
purchaser requires the seller to stamp the paper with hands and feet,
the four organs duly smeared with ink. Professional fortune tellers in
China take into account almost the entire system of the person whose
future they attempt to forecast, and of course they include palmistry,
but the rugæ of the finger-ends do not receive much attention. Amateur
fortune-tellers, however, discourse as glibly on them as phrenologists
do of "bumps"--it is so easy. In children the relative number of volute
and conical striæ indicate their future. "If there are nine volutes,"
says a proverb, "to one conical, the boy will attain distinction without

Regarded from an ethnological point of view, I can discover merely that
the rugæ of Chinamen's fingers differ from Europeans', but there is so
little uniformity observable that they form no basis for distinction,
and while the striæ may be noteworthy points in certain medico-legal
questions, heredity is not one of them.

       *       *       *       *       *


At the close of an interesting address lately delivered at the reopening
of the Liverpool University College and School of Medicine, Mr. Matthew
Arnold said if there was one word which he should like to plant in the
memories of his audience, and to leave sticking there after he had gone,
it was the word _lucidity_. If he had to fix upon the three great wants
at this moment of the three principal nations of Europe, he should say
that the great want of the French was morality, that the great want of
the Germans was civil courage, and that our own great want was lucidity.
Our own want was, of course, what concerned us the most. People were apt
to remark the defects which accompanied certain qualities, and to think
that the qualities could not be desirable because of the defects which
they saw accompanying them. There was no greater and salutary lesson for
men to learn than that a quality may be accompanied, naturally perhaps,
by grave dangers; that it may actually present itself accompanied by
terrible defects, and yet that it might itself be indispensable. Let him
illustrate what he meant by an example, the force of which they would
all readily feel. Seriousness was a quality of our nation. Perhaps
seriousness was always accompanied by certain dangers. But, at any rate,
many of our French neighbors would say that they found our seriousness
accompanied by so many false ideas, so much prejudice, so much that was
disagreeable, that it could not have the value which we attributed to
it. And yet we knew that it was invaluable. Let them follow the same
mode of reasoning as to the quality of lucidity. The French had a
national turn for lucidity as we had a national turn for seriousness.
Perhaps a national turn for lucidity carried with it always certain
dangers. Be this as it might, it was certain that we saw in the French,
along with their lucidity, a want of seriousness, a want of reverence,
and other faults, which greatly displeased us. Many of us were inclined
in consequence to undervalue their lucidity, or to deny that they
had it. We were wrong: it existed as our seriousness existed; it was
valuable as our seriousness was valuable. Both the one and the other
were valuable, and in the end indispensable.

What was lucidity? It was negatively that the French have it, and he
would therefore deal with its negative character merely. Negatively,
lucidity was the perception of the want of truth and validness in
notions long current, the perception that they are no longer possible,
that their time is finished, and they can serve us no more. All through
the last century a prodigious travail for lucidity was going forward
in France. Its principal agent was a man whose name excited generally
repulsion in England, Voltaire. Voltaire did a great deal of harm in
France. But it was not by his lucidity that he did harm; he did it by
his want of seriousness, his want of reverence, his want of sense for
much that is deepest in human nature. But by his lucidity he did good.

All admired Luther. Conduct was three-fourths of life, and a man who
worked for conduct, therefore, worked for more than a man who worked for
intelligence. But having promised this, it might be said that the Luther
of the eighteenth century and of the cultivated classes was Voltaire.
As Luther had an antipathy to what was immoral, so Voltaire had an
antipathy to what was absurd, and both of them made war upon the object
of their antipathy with such masterly power, with so much conviction,
so much energy, so much genius, that they carried their world with
them--Luther his Protestant world, and Voltaire his French world--and
the cultivated classes throughout the continent of Europe generally.

Voltaire had more than negative lucidity; he had the large and true
conception that a number and equilibrium of activities were necessary
for man. "_Il faut douner à notre áme toutes les formes possibles_"
was a maxim which Voltaire really and truly applied in practice,
"advancing," as Michelet finely said of him, in every direction with
a marvelous vigor and with that conquering ambition which Vico called
_mens heroica_. Nevertheless. Voltaire's signal characteristic was his
lucidity, his negative lucidity.

There was a great and free intellectual movement in England in the
eighteenth century--indeed, it was from England that it passed into
France; but the English had not that strong natural bent for lucidity
which the French had. Its bent was toward other things in preference.
Our leading thinkers had not the genius and passion for lucidity which
distinguished Voltaire. In their free inquiry they soon found themselves
coming into collision with a number of established facts, beliefs,
conventions. Thereupon all sorts of practical considerations began to
sway them. The danger signal went up, they often stopped short, turned
their eyes another way, or drew down a curtain between themselves and
the light. "It seems highly probable," said Voltaire, "that nature has
made thinking a portion of the brain, as vegetation is a function of
trees; that we think by the brain just as we walk by the feet." So our
reason, at least, would lead us to conclude, if the theologians did not
assure us of the contrary; such, too, was the opinion of Locke, but he
did not venture to announce it. The French Revolution came, England grew
to abhor France, and was cut off from the Continent, did great things,
gained much, but not in lucidity. The Continent was reopened, the
century advanced, time and experience brought their lessons, lovers of
free and clear thought, such as the late John Stuart Mill, arose among
us. But we could not say that they had by any means founded among us the
reign of lucidity.

Let them consider that movement of which we were hearing so much just
now: let them look at the Salvation Army and its operations. They would
see numbers, funds, energy, devotedness, excitement, conversions, and
a total absence of lucidity. A little lucidity would make the whole
movement impossible. That movement took for granted as its basis what
was no longer possible or receivable; its adherents proceeded in all
they did on the assumption that that basis was perfectly solid, and
neither saw that it was not solid, nor ever even thought of asking
themselves whether it was solid or not.

Taking a very different movement, and one of far higher dignity and
import, they had all had before their minds lately the long-devoted,
laborious, influential, pure, pathetic life of Dr. Pusey, which had just
ended. Many of them had also been reading in the lively volumes of that
acute, but not always good-natured rattle, Mr. Mozley, an account of
that great movement which took from Dr. Pusey its earlier name. Of its
later stage of Ritualism they had had in this country a now celebrated
experience. This movement was full of interest. It had produced men to
be respected, men to be admired, men to be beloved, men of learning,
goodness, genius, and charm. But could they resist the truth that
lucidity would have been fatal to it? The movers of all those questions
about apostolical succession, church patristic authority, primitive
usage, postures, vestments--questions so passionately debated, and on
which he would not seek to cast ridicule--did not they all begin by
taking for granted something no longer possible or receivable, build on
this basis as if it were indubitably solid, and fail to see that their
basis not being solid, all they built upon it was fantastic?

He would not say that negative lucidity was in itself a satisfactory
possession, but he said that it was inevitable and indispensable, and
that it was the condition of all serious construction for the future.
Without it at present a man or a nation was intellectually and
spiritually all abroad. If they saw it accompanied in France by much
that they shrank from, they should reflect that in England it would
have influences joined with it which it had not in France--the natural
seriousness of the people, their sense of reverence and respect, their
love for the past. Come it must; and here where it had been so late in
coming, it would probably be for the first time seen to come without

Capitals were natural centers of mental movement, and it was natural for
the classes with most leisure, most freedom, most means of cultivation,
and most conversance with the wide world to have lucidity though often
they had it not. To generate a spirit of lucidity in provincial towns,
and among the middle classes bound to a life of much routine and plunged
in business, was more difficult. Schools and universities, with serious
and disinterested studies, and connecting those studies the one with the
other and continuing them into years of manhood, were in this case the
best agency they could use. It might be slow, but it was sure. Such
an agency they were now going to employ. Might it fulfill all their
expectations! Might their students, in the words quoted just now,
advance in every direction with a marvelous vigor, and with that
conquering ambition which Vico called _mens heroica_! And among the many
good results of this, might one result be the acquisition in their midst
of that indispensable spirit--the spirit of lucidity!

       *       *       *       *       *


[Footnote: A. de Rochas in the _Revue Scientifique_.]

In the following notes I shall recall a few experiments that indicate
under what conditions the human organism is permitted to remain unharmed
amid flames. These experiments were published in England in 1882, in the
twelfth letter from Brewster to Walter Scott on natural magic. They are,
I believe, not much known in France, and possess a practical interest
for those who are engaged in the art of combating fires.

At the end of the last century Humphry Davy observed that, on placing a
very fine wire gauze over a flame, the latter was cooled to such a
point that it could not traverse the meshes. This phenomenon, which he
attributed to the conductivity and radiating power of the metal, he soon
utilized in the construction of a lamp for miners.

Some years afterward Chevalier Aldini, of Milan, conceived the idea of
making a new application of Davy's discovery in the manufacture of an
envelope that should permit a man to enter into the midst of flames.
This envelope, which was made of metallic gauze with 1-25th of an inch
meshes, was composed of five pieces, as follows: (1) a helmet, with
mask, large enough, to allow a certain space between it and the internal
bonnet of which I shall speak; (2) a cuirass with armlets; (3) a skirt
for the lower part of the belly and the thighs; (4) a pair of boots
formed of a double wire gauze; and (5) a shield five feet long by one
and a half wide, formed of metallic gauze stretched over a light iron
frame. Beneath this armor the experimenter was clad in breeches and a
close coat of coarse cloth that had previously been soaked in a solution
of alum. The head, hands, and feet were covered by envelopes of asbestos
cloth whose fibers were about a half millimeter in diameter. The bonnet
contained apertures for the eyes, nose, and ears, and consisted of a
single thickness of fabric, as did the stockings, but the gloves were of
double thickness, so that the wearer could seize burning objects with
the hands.

Aldini, convinced of the services that his apparatus might render to
humanity, traveled over Europe and gave gratuitous representations with
it. The exercises generally took place in the following order: Aldini
began by first wrapping his finger in asbestos and then with a double
layer of wire gauze. He then held it for some instants in the flame of
a candle or alcohol lamp. One of his assistants afterward put on the
asbestos glove of which I have spoken, and, protecting the palm of his
hand with another piece of asbestos cloth, seized a piece of red-hot
iron from a furnace and slowly carried it to a distance of forty or
fifty meters, lighted some straw with it, and then carried it back to
the furnace. On other occasions, the experimenters, holding firebrands
in their hands, walked for five minutes over a large grating under which
fagots were burning.

In order to show how the head, eyes, and lungs were protected by the
wire gauze apparatus, one of the experimenters put on the asbestos
bonnet, helmet, and cuirass, and fixed the shield in front of his
breast. Then, in a chafing dish placed on a level with his shoulder, a
great fire of shavings was lighted, and care was taken to keep it up.
Into the midst of these flames the experimenter then plunged his head
and remained thus five or six minutes with his face turned toward them.
In an exhibition given at Paris before a committee from the Academic
des Sciences, there were set up two parallel fences formed of straw,
connected by iron wire to light wicker work, and arranged so as to leave
between them a passage 3 feet wide by 30 long. The heat was so intense,
when the fences were set on fire, that no one could approach nearer than
20 or 25 feet; and the flames seemed to fill the whole space between
them, and rose to a height of 9 or 10 feet. Six men clad in the Aldini
suit went in, one behind the other, between the blazing fences, and
walked slowly backward and forward in the narrow passage, while the fire
was being fed with fresh combustibles from the exterior. One of these
men carried on his back, in an ozier basket covered with wire gauze, a
child eight years of age, who had on no other clothing than an asbestos
bonnet. This same man, having the child with him, entered on another
occasion a clear fire whose flames reached a height of 18 feet, and
whose intensity was such that it could not be looked at. He remained
therein so long that the spectators began to fear that he had succumbed;
but he finally came out safe and sound.

One of the conclusions to be drawn from the facts just stated is that
man can breathe in the midst of flames. This marvelous property cannot
be attributed exclusively to the cooling of the air by its passage
through the gauze before reaching the lungs; it shows also a very great
resistance of our organs to the action of heat. The following, moreover,
are direct proofs of such resistance. In England, in their first
experiment, Messrs. Joseph Banks, Charles Blagden, and Dr. Solander
remained for ten minutes in a hot-house whose temperature was 211°
Fahr., and their bodies preserved therein very nearly the usual heat. On
breathing against a thermometer they caused the mercury to fall several
degrees. Each expiration, especially when it was somewhat strong,
produced in their nostrils an agreeable impression of coolness, and the
same impression was also produced on their fingers when breathed upon.
When they touched themselves their skin seemed to be as cold as that of
a corpse; but contact with their watch chains caused them to experience
a sensation like that of a burn. A thermometer placed under the tongue
of one of the experimenters marked 98° Fahr., which is the normal
temperature of the human species.

Emboldened by these first results, Blagden entered a hot-house in which
the thermometer in certain parts reached 262° Fahr. He remained therein
eight minutes, walked about in all directions, and stopped in the
coolest part, which was at 240° Fahr. During all this time he
experienced no painful sensations; but, at the end of seven minutes, he
felt an oppression of the lungs that inquieted him and caused him to
leave the place. His pulse at that moment showed 144 beats to the
minute, that is to say, double what it usually did. To ascertain whether
there was any error in the indications of the thermometer, and to find
out what effect would take place on inert substances exposed to the hot
air that he had breathed, Blogden placed some eggs in a zinc plate in
the hot-house, alongside the thermometer, and found that in twenty
minutes they were baked hard.

A case is reported where workmen entered a furnace for drying moulds, in
England, the temperature of which was 177°, and whose iron sole plate
was so hot that it carbonized their wooden shoes. In the immediate
vicinity of this furnace the temperature rose to 160°. Persons not of
the trade who approached anywhere near the furnace experienced pain in
the eyes, nose, and ears.

A baker is cited in Angoumois, France, who spent ten minutes in a
furnace at 132° C.

The resistance of the human organism to so high temperatures can be
attributed to several causes. First, it has been found that the quantity
of carbonic acid exhaled by the lungs, and consequently the chemical
phenomena of internal combustion that are a source of animal heat,
diminish in measure as the external temperature rises. Hence, a conflict
which has for result the retardation of the moment at which a living
being will tend, without obstacle, to take the temperature of the
surrounding medium. On another hand, it has been observed that man
resists heat so much the less in proportion as the air is saturated
with vapors. Dr. Berger, who supported for seven minutes a temperature
varying from 109° to 110° C. in dry air, could remain only twelve
minutes in a bagnio whose temperature rose from 41° to 51.75°. At the
Hammam of Paris the highest temperature obtained is 87°, and Dr. E.
Martin has not been able to remain therein more than five minutes. This
physician reports that in 1743, the thermometer having exceeded 40° at
Pekin, 14,000 persons perished. These facts are explained by the cooling
that the evaporation of perspiration produces on the surface of the
body. Edwards has calculated that such evaporation is ten times greater
in dry air in motion than in calm and humid air. The observations become
still more striking when the skin is put in contact with a liquid or a
solid which suppresses perspiration. Lemoine endured a bath of Bareges
water of 37° for half an hour; but at 45° he could not remain in it more
than seven minutes, and the perspiration began to flow at the end of six
minutes. According to Brewster, persons who experience no malaise near
a fire which communicates a temperature of 100° C. to them, can hardly
bear contact with alcohol and oil at 55° and mercury at 48°.

The facts adduced permit us to understand how it was possible to bear
one of the proofs to which it is said those were submitted who wished
to be initiated into the Egyptian mysteries. In a vast vaulted chamber
nearly a hundred feet long, there were erected two fences formed of
posts, around which were wound branches of Arabian balm, Egyptian thorn,
and tamarind--all very flexible and inflammable woods. When this was set
on fire the flames arose as far as the vault, licked it, and gave the
chamber the appearance of a hot furnace, the smoke escaping through
pipes made for the purpose. Then the door was suddenly opened before the
neophyte, and he was ordered to traverse this burning place, whose floor
was composed of an incandescent grating.

The Abbé Terrason recounts all these details in his historic romance
"Sethos," printed at the end of last century. Unfortunately literary
frauds were in fashion then, and the book, published as a translation of
an old Greek manuscript, gives no indication of sources. I have sought
in special works for the data which the abbé must have had as a basis,
but I have not been able to find them. I suppose, however, that
this description, which is so precise, is not merely a work of the
imagination. The author goes so far as to give the dimensions of the
grating (30 feet by 8), and, greatly embarrassed to explain how his hero
was enabled to traverse it without being burned, is obliged to suppose
it to have been formed of very thick bars, between which Sethos had care
to place his feet. But this explanation is inadmissible. He who had the
courage to rush, head bowed, into the midst of the flames, certainly
would not have amused himself by choosing the place to put his feet.
Braving the fire that surrounded his entire body, he must have had no
other thought than that of reaching the end of his dangerous voyage as
soon as possible. We cannot see very well, moreover, how this immense
grate, lying on the ground, was raised to a red heat and kept at such a
temperature. It is infinitely more simple to suppose that between the
two fences there was a ditch sufficiently deep in which a fire had
also been lighted, and which was covered by a grating as in the Aldini
experiments. It is even probable that this grating was of copper,
which, illuminated by the fireplace, must have presented a terrifying
brilliancy, while in reality it served only to prevent the flames from
the fireplace reaching him who dared to brave them.

       *       *       *       *       *


The use of stone as a building material was not resorted to, except to
a trifling extent, in this country until long after the need of such a
solid substance was felt. The early settler contented himself with the
log cabin, the corduroy road, and the wooden bridge, and loose stone
enough for foundation purposes could readily be gathered from the
surface of the earth. Even after the desirability of more handsome and
durable building material for public edifices in the colonial cities
than wood became apparent, the ample resources which nature had afforded
in this country were overlooked, and brick and stone were imported by
the Dutch and English settlers from the Old World. Thus we find the
colonists of the New Netherlands putting yellow brick on their list
of non-dutiable imports in 1648; and such buildings in Boston as are
described as being "fairly set forth with brick, tile, slate, and
stone," were thus provided only with foreign products. Isolated
instances of quarrying stone are known to have occurred in the last
century; but they are rare. The edifice known as "King's Chapel,"
Boston, erected in 1752, is the first one on record as being built from
American stone; this was granite, brought from Braintree, Mass.

Granite is a rock particularly abundant in New England, though also
found in lesser quantities elsewhere in this country. The first granite
quarries that were extensively developed were those at Quincy, Mass.,
and work began at that point early in the present century. The fame of
the stone became widespread, and it was sent to distant markets--even to
New Orleans. The old Merchants' Exchange in New York (afterward used as
a custom house) the Astor House in that city, and the Custom House in
New Orleans, all nearly or quite fifty years old, were constructed of
Quincy granite, as were many other fine buildings along the Atlantic
coast. In later years, not only isolated public edifices, but also whole
blocks of stores, have been constructed of this material. It was from
the Quincy quarries that the first railroad in this country was built;
this was a horse-railroad, three miles long, extending to Neponset
River, built in 1827.

Other points in Massachusetts have been famed for their excellent
granite. After Maine was set off as a distinct State, Fox Island
acquired repute for its granite, and built up an extensive traffic
therein. Westerly, R.I., has also been engaged in quarrying this
valuable rock for many years, most of its choicer specimens having been
wrought for monumental purposes. Statues and other elaborate monumental
designs are now extensively made therefrom. Smaller pieces and a coarser
quality of the stone are here and elsewhere along the coast obtained in
large quantities for the construction of massive breakwaters to protect
harbors. Another point famous for its granite is Staten Island, New
York. This stone weighs 180 pounds to the cubic foot, while the Quincy
granite weighs but 165. The Staten Island product is used not only for
building purposes, but is also especially esteemed for paving after both
the Russ and Belgian patents. New York and other cities derive large
supplies from this source. The granite of Weehawken, N.J., is of the
same character, and greatly in demand. Port Deposit, Md., and Richmond,
Va, are also centers of granite production. Near Abbeville, S.C., and
in Georgia, granite is found quite like that of Quincy. Much southern
granite, however, decomposes readily, and is almost as soft as clay.
This variety of stone is found in great abundance in the Rocky
Mountains; but, except to a slight extent in California, it is not yet
quarried there.

Granite, having little grain, can be cut into blocks of almost any size
and shape. Specimens as much as eighty feet long have been taken out and
transported great distances. The quarrying is done by drilling a series
of small holes, six inches or more deep and almost the same distance
apart, inserting steel wedges along the whole line and then tapping each
gently with a hammer in succession, in order that the strain may be
evenly distributed.

A building material that came into use earlier than granite is known as
freestone or sandstone; although its first employment does not date back
further than the erection of King's Chapel, Boston, already referred to
as the earliest well-known occasion where granite was used in building.
Altogether the most famous American sandstone quarries are those at
Portland, on the Connecticut River, opposite Middletown. These were
worked before the Revolution; and their product has been shipped to many
distant points in the country. The long rows of "brownstone fronts" in
New York city are mostly of Portland stone, though in many cases the
walls are chiefly of brick covered with thin layers of the stone. The
old red sandstone of the Connecticut valley is distinguished in geology
for the discovery of gigantic fossil footprints of birds, first noticed
in the Portland quarries in 1802. Some of these footprints measured
ten to sixteen inches, and they were from four to six feet apart. The
sandstone of Belleville, N.J., has also extensive use and reputation.
Trinity Church in New York city and the Boston Atheneum are built of the
product of these quarries; St. Lawrence County, New York, is noted also
for a fine bed of sandstone. At Potsdam it is exposed to a depth of
seventy feet. There are places though, in New England, New York, and
Eastern Pennsylvania, where a depth of three hundred feet has been
reached. The Potsdam sandstone is often split to the thinness of an
inch. It hardens by exposure, and is often used for smelting furnace
hearth-stones. Shawangunk Mountain, in Ulster County, yields a sandstone
of inferior quality, which has been unsuccessfully tried for paving;
as it wears very unevenly. From Ulster, Greene, and Albany Counties
sandstone slabs for sidewalks are extensively quarried for city use;
the principal outlets of these sections being Kingston, Saugerties,
Coxsackie, Bristol, and New Baltimore, on the Hudson. In this region
quantities amounting to millions of square feet are taken out in large
sheets, which are often sawed into the sizes desired. The vicinity of
Medina, in Western New York, yields a sandstone extensively used in that
section for paving and curbing, and a little for building. A rather poor
quality of this stone has been found along the Potomac, and some of it
was used in the erection of the old Capitol building at Washington.
Ohio yields a sandstone that is of a light gray color; Berea, Amherst,
Vermilion, and Massillon are the chief points of production. St.
Genevieve, Mo., yields a stone of fine grain of a light straw color,
which is quite equal to the famous Caen stone of France. The Lake
Superior sandstones are dark and coarse grained, but strong.

In some parts of the country, where neither granite nor sandstone
is easily procured, blue and gray limestone are sometimes used for
building, and, when hammer dressed, often look like granite. A serious
objection to their use, however, is the occasional presence of iron,
which rusts on exposure, and defaces the building. In Western New York
they are widely used. Topeka stone, like the coquine of Florida and
Bermuda, is soft like wood when first quarried, and easily wrought,
but it hardens on exposure. The limestones of Canton, Mo., Joliet and
Athens, Ill., Dayton, Sandusky, Marblehead, and other points in Ohio,
Ellittsville, Ind., and Louisville and Bowling Green, Ky., are great
favorites west. In many of these regions limestone is extensively used
for macadamizing roads, for which it is excellently adapted. It also
yields excellent slabs or flags for sidewalks.

One of the principal uses of this variety of stone is its conversion, by
burning, into lime for building purposes. All limestones are by no
means equally excellent in this regard. Thomaston lime, burned with
Pennsylvania coal, near the Penobscot River, has had a wide reputation
for nearly half a century. It has been shipped thence to all points
along the Atlantic coast, invading Virginia as far as Lynchburg, and
going even to New Orleans, Smithfield, R.I., and Westchester County,
N.Y., near the lower end of the Highlands, also make a particularly
excellent quality of lime. Kingston, in Ulster County, makes an inferior
sort for agricultural purposes. The Ohio and other western stones yield
a poor lime, and that section is almost entirely dependent on the east
for supplies.

Marbles, like limestones, with which they are closely related, are very
abundant in this country, and are also to be found in a great variety of
colors. As early as 1804 American marble was used for statuary purposes.
Early in the century it also obtained extensive employment for
gravestones. Its use for building purposes has been more recent than
granite and sandstone in this country; and it is coming to supersede the
latter to a great degree. For mantels, fire-places, porch pillars, and
like ornamental purposes, however, our variegated, rich colored and
veined or brecciated marbles were in use some time before exterior walls
were made from them. Among the earliest marble buildings were Girard
College in Philadelphia and the old City Hall in New York, and the
Custom House in the latter city, afterward used for a sub-treasury. The
new Capitol building at Washington is among the more recent structures
composed of this material. Our exports of marble to Cuba and elsewhere
amount to over $300,000 annually, although we import nearly the same
amount from Italy. And yet an article can be found in the United States
fully as fine as the famous Carrara marble. We refer to that which comes
from Rutland, Vt. This state yields the largest variety and choicest
specimens. The marble belt runs both ways from Rutland County, where
the only quality fit for statuary is obtained. Toward the north it
deteriorates by growing less sound, though finer in grain; while to
the south it becomes coarser. A beautiful black marble is obtained at
Shoreham, Vt. There are also handsome brecciated marbles in the same
state; and in the extreme northern part, near Lake Champlain, they
become more variegated and rich in hue. Such other marble as is found
in New England is of an inferior quality. The pillars of Girard
College came from Berkshire, Mass., which ranks next after Vermont in

The marble belt extends from New England through New York, Pennsylvania,
Maryland, the District of Columbia, and Virginia, Tennessee, and the
Carolinas, to Georgia and Alabama. Some of the variegated and high
colored varieties obtained near Knoxville, Tenn., nearly equal that of
Vermont. The Rocky Mountains contain a vast abundance and variety.

Slate was known to exist in this country to a slight extent in colonial
days. It was then used for gravestones, and to some extent for roofing
and school purposes. But most of our supplies came from Wales. It is
stated that a slate quarry was operated in Northampton County, Pa., as
early as 1805. In 1826 James M. Porter and Samuel Taylor engaged in the
business, obtaining their supplies from the Kittanninny Mountains. From
this time the business developed rapidly, the village of Slateford being
an outgrowth of it, and large rafts being employed to float the product
down the Schuylkill to Philadelphia. By 1860 the industry had reached
the capacity of 20,000 cases of slate, valued at $10 a case, annually.
In 1839 quarries were opened in the Piscataquis River, forty miles
north of Bangor, Me., but poor transportation facilities retarded the
business. Vermont began to yield in 1852. New York's quarries are
confined to Washington County, near the Vermont line. Maryland has
a limited supply from Harford County. The Huron Mountains, north of
Marquette, Mich., contain slate, which is also said to exist in Pike
County, Ga.

Grindstones, millstones, and whetstones are quarried in New York, Ohio,
Michigan, Pennsylvania, and other States. Mica is found at Acworth and
Grafton, N. H., and near Salt Lake, but our chief supply comes from
Haywood, Yancey, Mitchell, and Macon counties, in North Carolina, and
our product is so large that we can afford to export it. Other stones,
such as silex, for making glass, etc., are found in profusion in various
parts of the country, but we have no space to enter into a detailed
account of them at present.--_Pottery and Glassware Reporter_.

       *       *       *       *       *


The most interesting change of which the Census gives account is the
increase in the number of farms. The number has virtually doubled within
twenty years. The population of the country has not increased in like
proportion. A large part of the increase in number of farms has been due
to the division of great estates. Nor has this occurred, as some may
imagine, exclusively in the Southern States and the States to which
immigration and migration have recently been directed. It is an
important fact that the multiplication of farms has continued even in
the older Northern States, though the change has not been as great in
these as in States of the far West or the South. In New York there has
been an increase of 25,000, or 11.5 per cent, in the number of farms
since 1870; in New Jersey the increase has been 12.2 per cent., and in
Pennsylvania 22.7 per cent., though the increase in population, and
doubtless in the number of persons engaged in farming, has been much
smaller. Ohio, Indiana, and Illinois also, have been considered fully
settled States for years, at least in an agricultural point of view, and
yet the number of farms has increased 26.1 per cent, in ten years in
Ohio, 20.3 percent, in Indiana, and 26.1 per cent, in Illinois. The
obvious explanation is that the growth of many cities and towns has
created a market for a far greater supply of those products which may be
most advantageously grown upon farms of moderate size; but even if this
fully accounts for the phenomenon, the change must be recognized as one
of the highest importance industrially, socially, and politically. The
man who owns or rents and cultivates a farm stands on a very different
footing from the laborer who works for wages. It is not a small matter
that, in these six States alone, there are 205,000 more owners or
managers of farms than there were only a decade ago.

As we go further toward the border, west or north, the influence of the
settlement of new land is more distinctly felt. Even in Michigan, where
new railroads have opened new regions to settlement, the increase in
number of farms has been over 55 per cent. In Wisconsin, though the
increase in railroad mileage has been about the same as in Michigan, the
reported increase in number of farms has been only 28 per cent., but in
Iowa it rises to 60 per cent., and in Minnesota to nearly 100 per cent.
In Kansas the number of farms is 138,561, against 38,202 in 1870; in
Nebraska 63,387, against 12,301; and in Dakota 17,435, against 1,720. In
these regions the process is one of creation of new States rather than a
change in the social and industrial condition of the population.

Some Southern States have gained largely, but the increase in these,
though very great, is less surprising than the new States of the
Northwest. The prevailing tendency of Southern agriculture to large
farms and the employment of many hands is especially felt in States
where land is still abundant. The greatest increase is in Texas, where
174,184 farms are reported, against 61,125 in 1870; in Florida, with
23,438 farms, against 10,241 in 1870; and in Arkansas, with 94,433
farms, against 49,424 in 1870. In Missouri 215,575 farms are reported,
against 148,228 in 1870. In these States, though social changes have
been great, the increase in number of farms has been largely due to new
settlements, as in the States of the far Northwest. But the change in
the older Southern States is of a different character.

Virginia, for example, has long been settled, and had 77,000 farms
thirty years ago. But the increase in number within the past ten years
has been 44,668, or 60.5 per cent. Contrasting this with the increase in
New York, a remarkable difference appears. West Virginia had few more
farms ten years ago than New Jersey; now it has nearly twice as many,
and has gained in number nearly 60 per cent. North Carolina, too, has
increased 78 per cent. in number of farms since 1870, and South Carolina
80 per cent. In Georgia the increase has been still greater--from 69,956
to 138,626, or nearly 100 per cent. In Alabama there are 135,864
farms, against 67,382 in 1870, an increase of over 100 per cent. These
proportions, contrasted with those for the older Northern States, reveal
a change that is nothing less than an industrial revolution. But the
force of this tendency to division of estates has been greatest in the
States named. Whereas the ratio of increase in number of farms becomes
greater in Northern States as we go from the East toward the Mississippi
River, at the South it is much smaller in Kentucky, Tennessee,
Mississippi, and Louisiana than in the older States on the Atlantic
coast. Thus in Louisiana the increase has been from 28,481 to 48,292
farms, or 70 per cent., and in Mississippi from 68,023 to 101,772 farms,
or less than 50 per cent., against 100 in Alabama and Georgia. In
Kentucky the increase has been from 118,422 to 166,453 farms, or 40 per
cent., and in Tennessee from 118,141 to 165,650 farms, or 40 per cent.,
against 60 in Virginia and West Virginia, and 78 in North Carolina.
Thus, while the tendency to division is far greater than in the Northern
States of corresponding age, it is found in full force only in six of
the older Southern States, Alabama, West Virginia, and four on the
Atlantic coast. In these, the revolution already effected foreshadows
and will almost certainly bring about important political changes within
a few years. In these six States there 310,795 more farm owners or
occupants than there were ten years ago.--_N.Y. Tribune_.

       *       *       *       *       *


For information about burning lime we republish the following article
furnished by a correspondent of the _Country Gentleman_ several years

[Illustration: Fig. 1. Fig. 2. Fig. 3. A (Fig. 1), Railway Track--B B B,
Iron Rods running through Kiln--C, Capstone over Arch--D, Arch--E, Well
without brick or ash lining.]

I send you a description and sketch of a lime-kiln put up on my premises
about five years ago. The dimensions of this kiln are 13 feet square by
25 feet high from foundation, and its capacity 100 bushels in 24 hours.
It was constructed of the limestone quarried on the spot. It has round
iron rods (shown in sketch) passing through, with iron plates fastened
to the ends as clamps to make it more firm; the pair nearest the top
should be not less than 2 feet from that point, the others interspersed
about 2 feet apart--the greatest strain being near the top. The arch
should be 7 feet high by 5½ wide in front, with a gather on the top
and sides of about 1 foot, with plank floor; and if this has a little
incline it will facilitate shoveling the lime when drawn. The arch
should have a strong capstone; also one immediately under the well of
the kiln, with a hole 2 feet in diameter to draw the lime through; or
two may be used with semicircle cut in each. Iron bars 2 inches wide by
1/8 inch thick are used in this kiln for closing it, working in slots
fastened to capstone. These slots must be put in before the caps
are laid. When it is desired to draw lime, these bars may be
pushed laterally in the slots, or drawn out entirely, according to
circumstances; 3 bars will be enough. The slots are made of iron bars
1½ inches wide, with ends rounded and turned up, and inserted in holes
drilled through capstone and keyed above.

The well of the kiln is lined with fire-brick one course thick, with a
stratum of coal ashes three inches thick tamped in between the brick
and wall, which proves a great protection to the wall. About 2,000
fire-bricks were used. The proprietors of this kiln say about one-half
the lower part of the well might have been lined with a first quality of
common brick and saved some expense and been just as good. The form of
the well shown in Fig. 3 is 7 feet in diameter in the bilge, exclusive
of the lining of brick and ashes. Experiments in this vicinity have
proved this to be the best, this contraction toward the top being
absolutely necessary, the expansion of the stone by the heat is so
great that the lime cannot be drawn from perpendicular walls, as was
demonstrated in one instance near here, where a kiln was built on that
principle. The kiln, of course, is for coal, and our stone requires
about three-quarters of a ton per 100 bushels of lime, but this, I am
told, varies according to quality, some requiring more than others; the
quantity can best be determined by experimenting; also the regulation of
the heat--if too great it will cause the stones to melt or run together
as it were, or, if too little, they will not be properly burned. The
business requires skill and judgment to run it successfully.

This kiln is located at the foot of a steep bluff, the top about level
with the top of the kiln, with railway track built of wooden sleepers,
with light iron bars, running from the bluff to the top of the kiln, and
a hand-car makes it very convenient filling the kiln. Such a location
should be had if possible. Your inquirer may perhaps get some ideas
of the principles of a kiln for using _coal_. The dimensions may be
reduced, if desired. If for _wood_, the arch would have to be formed for
that, and the height of kiln reduced.

       *       *       *       *       *


[Footnote: From the report of the New York Agricultural Society.]

Within the county of Oswego, New York, Dewitt C. Peck reports there are
five apple jelly factories in operation. The failure of the apple crop,
for some singular and unexplained reason, does not extend in great
degree to the natural or ungrafted fruit. Though not so many as common,
even of these apples, there are yet enough to keep these five mills and
the numerous cider mills pretty well employed. The largest jelly factory
is located near the village of Mexico, and as there are some features in
regard to this manufacture peculiar to this establishment which may be
new and interesting, we will undertake a brief description. The factory
is located on the Salmon Creek, which affords the necessary power. A
portion of the main floor, first story, is occupied as a saw mill,
the slabs furnishing fuel for the boiler furnace connected with the
evaporating department. Just above the mill, along the bank of the pond,
and with one end projecting over the water, are arranged eight large
bins, holding from five hundred to one thousand bushels each, into which
the apples are delivered from the teams. The floor in each of these has
a sharp pitch or inclination toward the water and at the lower end is a
grate through which the fruit is discharged, when wanted, into a trough
half submerged in the pond.

The preparation of the fruit and extraction of the juice proceeds
as follows: Upon hoisting a gate in the lower end of this trough,
considerable current is caused, and the water carries the fruit a
distance of from thirty to one hundred feet, and passes into the
basement of the mill, where, tumbling down a four-foot perpendicular
fall, into a tank, tight in its lower half and slatted so as to permit
the escape of water and impurities in the upper half, the apples are
thoroughly cleansed from all earthy or extraneous matter. Such is the
friction caused by the concussion of the fall, the rolling and rubbing
of the apples together, and the pouring of the water, that decayed
sections of the fruit are ground off and the rotten pulp passes away
with other impurities. From this tank the apples are hoisted upon an
endless chain elevator, with buckets in the form of a rake-head with
iron teeth, permitting drainage and escape of water, to an upper story
of the mill, whence by gravity they descend to the grater. The press
is wholly of iron, all its motions, even to the turning of the screws,
being actuated by the water power. The cheese is built up with layers
inclosed in strong cotton cloth, which displaces the straw used in olden
time, and serves also to strain the cider. As it is expressed from
the press tank, the cider passes to a storage tank, and thence to the

This defecator is a copper pan, eleven feet long and about three feet
wide. At each end of this pan is placed a copper tube three inches in
diameter and closed at both ends. Lying between and connecting
these two, are twelve tubes, also of copper, 1½ inches in diameter,
penetrating the larger tubes at equal distances from their upper and
under surfaces, the smaller being parallel with each other, and 1½
inches apart. When placed in position, the larger tubes, which act as
manifolds, supplying the smaller with steam, rest upon the bottom of the
pan, and thus the smaller pipes have a space of three-fourths of an inch
underneath their outer surfaces.

The cider comes from the storage tank in a continuous stream about
three-eighths of an inch in diameter. Steam is introduced to the large
or manifold tubes, and from them distributed through the smaller ones at
a pressure of from twenty-five to thirty pounds per inch. Trap valves
are provided for the escape of water formed by condensation within the
pipes. The primary object of the defecator is to remove all impurities
and perfectly clarify the liquid passing through it. All portions of
pomace and other minute particles of foreign matter, when heated,
expand and float in the form of scum upon the surface of the cider. An
ingeniously contrived floating rake drags off this scum and delivers it
over the side of the pan. To facilitate this removal, one side of the
pan, commencing at a point just below the surface of the cider, is
curved gently outward and upward, terminating in a slightly inclined
plane, over the edge of which the scum is pushed by the rake into a
trough and carried away. A secondary purpose served by the defecator
is that of reducing the cider by evaporation to a partial sirup of the
specific gravity of about 20° Baume. When of this consistency the liquid
is drawn from the bottom and less agitated portion of the defecator by a
siphon, and thence carried to the evaporator, which is located upon the
same framework and just below the defecator.

The evaporator consists of a separate system of six copper tubes, each
twelve feet long and three inches in diameter. These are each jacketed
or inclosed in an iron pipe of four inches internal diameter, fitted
with steam-tight collars so as to leave half an inch steam space
surrounding the copper tubes. The latter are open at both ends
permitting the admission and egress of the sirup and the escape of the
steam caused by evaporation therefrom, and are arranged upon the frame
so as to have a very slight inclination downward in the direction of
the current, and each nearly underneath its predecessor in regular
succession. Each is connected by an iron supply pipe, having a steam
gauge or indicator attached, with a large manifold, and that by other
pipes with a steam boiler of thirty horse power capacity. Steam being
let on at from twenty five to thirty pounds pressure, the stream of
sirup is received from the defecator through a strainer, which removes
any impurities possibly remaining into the upper evaporator tube;
passing in a gentle flow through that, it is delivered into a funnel
connected with the next tube below, and so, back and forth, through the
whole system. The sirup enters the evaporator at a consistency of from
20° to 23° Baume, and emerges from the last tube some three minutes
later at a consistency of from 30° to 32° Baume, which is found on
cooling to be the proper point for perfect jelly. This point is found to
vary one or two degrees, according to the fermentation consequent upon
bruises in handling the fruit, decay of the same, or any little delay in
expressing the juice from the cheese. The least fermentation occasions
the necessity for a lower reduction. To guard against this, no cheese
is allowed to stand over night, no pomace left in the grater or vat, no
cider in the tank; and further to provide against fermentation, a large
water tank is located upon the roof and filled by a force pump, and by
means of hose connected with this, each grater, press, vat, tank, pipe,
trough, or other article of machinery used, can be thoroughly washed and
cleansed. Hot water, instead of cider, is sometimes sent through the
defecator, evaporator, etc., until all are thoroughly scalded and
purified. If the saccharometer shows too great or too little reduction,
the matter is easily regulated by varying the steam pressure in the
evaporator by means of a valve in the supply pipe. If boiled cider
instead of jelly is wanted for making pies, sauces, etc., it is drawn
off from one of the upper evaporator tubes according to the consistency
desired; or can be produced at the end of the process by simply reducing
the steam pressure.

As the jelly emerges from the evaporator it is transferred to a tub
holding some fifty gallons, and by mixing a little therein, any little
variations in reduction or in the sweetness or sourness of the fruit
used are equalized. From this it is drawn through faucets, while hot,
into the various packages in which it is shipped to market. A favorite
form of package for family use is a nicely turned little wooden
bucket with cover and bail, two sizes, holding five and ten pounds
respectively. The smaller packages are shipped in cases for convenience
in handling. The present product of this manufactory is from 1,500 to
1,800 pounds of jelly each day of ten hours. It is calculated that
improvements now in progress will increase this to something more than a
ton per day. Each bushel of fruit will produce from four to five pounds
of jelly, fruit ripening late in the season being more productive than
earlier varieties. Crab apples produce the finest jelly; sour, crabbed,
natural fruit makes the best looking article, and a mixture of all
varieties gives most satisfactory results as to flavor and general

As the pomace is shoveled from the finished cheese, it is again ground
under a toothed cylinder, and thence drops into large troughs, through a
succession of which a considerable stream of water is flowing. Here it
is occasionally agitated by raking from the lower to the upper end of
the trough as the current carries it downward, and the apple seeds
becoming disengaged drop to the bottom into still water, while the pulp
floats away upon the stream. A succession of troughs serves to remove
nearly all the seeds. The value of the apple seeds thus saved is
sufficient to pay the daily wages of all the hands employed in the whole
establishment. The apples are measured in the wagon box, one and a half
cubic feet being accounted a bushel.

This mill ordinarily employs about six men: One general superintendent,
who buys and measures the apples, keeps time books, attends to all the
accounts and the working details of the mill, and acts as cashier; one
sawyer, who manufactures lumber for the local market and saws the slabs
into short lengths suitable for the furnace; one cider maker, who grinds
the apples and attends the presses; one jelly maker, who attends the
defecator, evaporator, and mixing tub, besides acting as his own fireman
and engineer; one who attends the apple seed troughs and acts as general
helper, and one man-of-all-work to pack, ship and assist whenever
needed. The establishment was erected late in the season of 1880,
and manufactured that year about forty-five tons of jelly, besides
considerable cider exchanged to the farmers for apples, and some boiled

The price paid for apples in 1880, when the crop was superabundant, was
six to eight cents per bushel; in 1881, fifteen cents. The proprietor
hopes next year to consume 100,000 bushels. These institutions are
important to the farmer in that they use much fruit not otherwise
valuable and very perishable. Fruit so crabbed and gnarled as to have no
market value, and even frozen apples, if delivered while yet solid, can
be used. (Such apples are placed in the water while frozen, the water
draws the frost sufficiently to be grated, and passing through the press
and evaporator before there is time for chemical change, they are found
to make very good jelly. They are valuable to the consumer by converting
the perishable, cheap, almost worthless crop of the bearing and abundant
years into such enduring form that its consumption may be carried over
to years of scarcity and furnish healthful food in cheap and pleasant
form to many who would otherwise be deprived; and lastly, they are of
great interest to society, in that they give to cider twice the value
for purposes of food that it has or can have, even to the manufacturer,
for use as a beverage and intoxicant.

       *       *       *       *       *


It stands to reason that were our summers warmer we should be able to
grow grapes successfully on open walls; it is therefore probable that
a new grape bag, the invention of M. Pelletier, 20 Rue de la Banque,
Paris, intended to serve a double purpose, viz., protecting the fruit
and hastening its maturity, will, when it becomes known, be welcomed in
this country. It consists of a square of curved glass so fixed to
the bag that the sun's rays are concentrated upon the fruit, thereby
rendering its ripening more certain in addition to improving its quality
generally. The glass is affixed to the bag by means of a light iron wire
support. It covers that portion of it next the sun, so that it increases
the amount of light and warms the grapes without scorching them, a
result due to the convexity of the glass and the layer of air between it
and the bag. M. Pelletier had the idea of rendering these bags cheaper
by employing plain squares instead of curved ones, but the advantage
thus obtained was more than counterbalanced by their comparative
inefficacy. In practice it was found that the curved squares gave an
average of 7° more than the straight ones, while there was a difference
of 10° when the bags alone were used, thus plainly demonstrating the
practical value of the invention.

Whether these glass-fronted bags would have much value in the case of
grapes grown under glass in the ordinary way is a question that can only
be determined by actual experiment; but where the vines are on walls,
either under glass screens or in the open air, so that the bunches feel
the full force of the sun's rays, there can be no doubt as to their
utility, and it is probable that by their aid many of the continental
varieties which we do not now attempt to grow in the open, and which are
scarcely worthy of a place under glass, might be well ripened. At
any rate we ought to give anything a fair trial which may serve to
neutralize, if only in a slight degree, the uncertainty of our summers.
As it is, we have only about two varieties of grapes, and these not the
best of the hardy kinds, as regards flavor and appearance, that ripen
out of doors, and even these do not always succeed. We know next to
nothing of the many really well-flavored kinds which are so much
appreciated in many parts of the Continent. The fact is, our outdoor
culture of grapes offers a striking contrast to that practiced under
glass, and although our comparatively sunless and moist climate affords
some excuse for our shortcomings in this respect, there is no valid
reason for the utter want of good culture which is to be observed in a
general way.

[Illustration: GRAPE BAG.--OPEN.]

Given intelligent training, constant care in stopping the laterals, and
checking mildew as well as thinning the berries, allowing each bunch to
get the full benefit of sun and air, and I believe good eatable grapes
would often be obtained even in summers marked by a low average

[Illustration: GRAPE BAG.--CLOSED.]

If, moreover, to a good system of culture we add some such mechanical
contrivance as that under notice whereby the bunches enjoy an average
warmth some 10° higher than they otherwise would do, we not only insure
the grapes coming to perfection in favored districts, but outdoor
culture might probably be practiced in higher latitudes than is now


The improved grape bag would also offer great facilities for destroying
mildew or guarantee the grapes against its attacks, as a light dusting
administered as soon as the berries were fairly formed would suffice for
the season, as owing to the glass protecting the berries from driving
rains, which often accompany south or south-west winds in summer and
autumn, the sulphur would not be washed off.


The inventor claims, and we should say with just reason, that these
glass fronted bags would be found equally serviceable for the ripening
of pears and other choice fruits, and with a view to their being
employed for such a purpose, he has had them made of varying sizes and
shapes. In conclusion, it may be observed that, in addition to advancing
the maturity of the fruits to which they are applied, they also serve to
preserve them from falling to the ground when ripe.--J. COBNHILL, _in
the Garden_.

       *       *       *       *       *


At a popular fête in the Tuileries Gardens I was struck with an
experiment which seems deserving of the immediate attention of the
English public and military authorities.

Among the attractions of the fête was an apparatus for the concentration
and utilization of solar heat, and, though the sun was not very
brilliant, I saw this apparatus set in motion a printing machine which
printed several thousand copies of a specimen newspaper entitled the
_Soleil Journal_.

The sun's rays are concentrated in a reflector, which moves at the
same rate as the sun and heats a vertical boiler, setting the motive
steam-engine at work. As may be supposed, the only object was to
demonstrate the possibility of utilizing the concentrated heat of the
solar rays; but I closely examined it, because the apparatus seems
capable of great utility in existing circumstances. Here in France,
indeed, there is a radical drawback--the sun is often overclouded.

Thousands of years ago the idea of utilizing the solar rays must have
suggested itself, and there are still savage tribes who know no other
mode of combustion; but the scientific application has hitherto been
lacking. This void this apparatus will fill up. About fifteen years ago
Professor Mouchon, of Tours, began constructing such an apparatus, and
his experiments have been continued by M. Pifre, who has devoted much
labor and expense to realizing M. Mouchou's idea. A company has now come
to his aid, and has constructed a number of apparatus of different sizes
at a factory which might speedily turn out a large number of them. It is
evident that in a country of uninterrupted sunshine the boiler might be
heated in thirty or forty minutes. A portable apparatus could boil two
and one-half quarts an hour, or, say, four gallons a day, thus supplying
by distillation or ebullition six or eight men. The apparatus can be
easily carried on a man's back, and on condition of water, even of the
worst quality, being obtainable, good drinking and cooking water is
insured. M. De Rougaumond, a young scientific writer, has just published
an interesting volume on the invention. I was able yesterday to verify
his statements, for I saw cider made, a pump set in motion, and coffee
made--in short, the calorific action of the sun superseding that of
fuel. The apparatus, no doubt, has not yet reached perfection, but as it
is it would enable the soldier in India or Egypt to procure in the field
good water and to cook his food rapidly. The invention is of especial
importance to England just now, but even when the Egyptian question is
settled the Indian troops might find it of inestimable value.

Red tape should for once be disregarded, and a competent commission
forthwith sent to 30 Rue d'Assas, with instructions to report
immediately, for every minute saved may avoid suffering for Englishmen
fighting abroad for their country. I may, of course, be mistaken, but
a commission would decide, and if the apparatus is good the slightest
delay in its adoption would be deplorable.--_Paris Correspondence London

       *       *       *       *       *


[Footnote: A paper read before the Engineers' Club of Philadelphia.]



The discovery of the magnetic needle was a boon to mankind, and has been
of inestimable service in guiding the mariner through trackless waters,
and the explorer over desert wastes. In these, its legitimate uses, the
needle has not a rival, but all efforts to apply it to the accurate
determination of permanent boundary lines have proven very
unsatisfactory, and have given rise to much litigation, acerbity, and
even death.

For these and other cogent reasons, strenuous efforts are being made to
dispense, so far as practicable, with the use of the magnetic needle
in surveying, and to substitute therefor the more accurate method of
traversing from a true meridian. This method, however, involves a
greater degree of preparation and higher qualifications than are
generally possessed, and unless the matter can be so simplified as to be
readily understood, it is unreasonable to expect its general application
in practice.

Much has been written upon the various methods of determining, the
true meridian, but it is so intimately related to the determination of
latitude and time, and these latter in turn upon the fixing of a true
meridian, that the novice can find neither beginning nor end. When to
these difficulties are added the corrections for parallax, refraction,
instrumental errors, personal equation, and the determination of the
probable error, he is hopelessly confused, and when he learns that time
may be sidereal, mean solar, local, Greenwich, or Washington, and he is
referred to an ephemeris and table of logarithms for data, he becomes
lost in "confusion worse confounded," and gives up in despair, settling
down to the conviction that the simple method of compass surveying is
the best after all, even if not the most accurate.

Having received numerous requests for information upon the subject, I
have thought it expedient to endeavor to prepare a description of the
method of determining the true meridian which should be sufficiently
clear and practical to be generally understood by those desiring to make
use of such information.

This will involve an elementary treatment of the subject, beginning with


The _celestial sphere_ is that imaginary surface upon which all
celestial objects are projected. Its radius is infinite.

The _earth's axis_ is the imaginary line about which it revolves.

The _poles_ are the points in which the axis pierces the surface of the
earth, or of the celestial sphere.

A _meridian_ is a great circle of the earth cut out by a plane passing
through the axis. All meridians are therefore north and south lines
passing through the poles.

From these definitions it follows that if there were a star exactly at
the pole it would only be necessary to set up an instrument and take a
bearing to it for the meridian. Such not being the case, however, we are
obliged to take some one of the near circumpolar stars as our object,
and correct the observation according to its angular distance from the
meridian at the time of observation.

For convenience, the bright star known as Ursæ Minoris or Polaris, is
generally selected. This star apparently revolves about the north pole,
in an orbit whose mean radius is 1° 19' 13",[1] making the revolution in
23 hours 56 minutes.

[Footnote 1: This is the codeclination as given in the Nautical Almanac.
The mean value decreases by about 20 seconds each year.]

During this time it must therefore cross the meridian twice, once above
the pole and once below; the former is called the _upper_, and the
latter the _lower meridian transit or culmination_. It must also pass
through the points farthest east and west from the meridian. The former
is called the _eastern elongation_, the latter the _western_.

An observation may he made upon Polaris at any of these four points,
or at any other point of its orbit, but this latter case becomes too
complicated for ordinary practice, and is therefore not considered.

If the observation were made upon the star at the time of its upper or
lower culmination, it would give the true meridian at once, but this
involves a knowledge of the true local time of transit, or the longitude
of the place of observation, which is generally an unknown quantity; and
moreover, as the star is then moving east or west, or at right angles to
the place of the meridian, at the rate of 15° of arc in about one hour,
an error of so slight a quantity as only four seconds of time would
introduce an error of one minute of arc. If the observation be made,
however, upon either elongation, when the star is moving up or down,
that is, in the direction of the vertical wire of the instrument, the
error of observation in the angle between it and the pole will be
inappreciable. This is, therefore, the best position upon which to make
the observation, as the precise time of the elongation need not be
given. It can be determined with sufficient accuracy by a glance at the
relative positions of the star Alioth, in the handle of the Dipper,
and Polaris (see Fig. 1). When the line joining these two stars is
horizontal or nearly so, and Alioth is to the _west_ of Polaris, the
latter is at its _eastern_ elongation, and _vice versa_, thus:


But since the star at either elongation is off the meridian, it will
be necessary to determine the angle at the place of observation to be
turned off on the instrument to bring it into the meridian. This angle,
called the azimuth of the pole star, varies with the latitude of the
observer, as will appear from Fig 2, and hence its value must be
computed for different latitudes, and the surveyor must know his
_latitude_ before he can apply it. Let N be the north pole of the
celestial sphere; S, the position of Polaris at its eastern elongation;
then N S=1° 19' 13", a constant quantity. The azimuth of Polaris at the
latitude 40° north is represented by the angle N O S, and that at 60°
north, by the angle N O' S, which is greater, being an exterior angle
of the triangle, O S O. From this we see that the azimuth varies at the

We have first, then, to _find the latitude of the place of observation_.

Of the several methods for doing this, we shall select the simplest,
preceding it by a few definitions.

A _normal_ line is the one joining the point directly overhead, called
the _zenith_, with the one under foot called the _nadir_.

The _celestial horizon_ is the intersection of the celestial sphere by a
plane passing through the center of the earth and perpendicular to the

A _vertical circle_ is one whose plane is perpendicular to the horizon,
hence all such circles must pass through the normal and have the zenith
and nadir points for their poles. The _altitude_ of a celestial object
is its distance above the horizon measured on the arc of a vertical
circle. As the distance from the horizon to the zenith is 90°, the
difference, or _complement_ of the altitude, is called the _zenith
distance_, or _co-altitude_.

The _azimuth_ of an object is the angle between the vertical plane
through the object and the plane of the meridian, measured on the
horizon, and usually read from the south point, as 0°, through west, at
90, north 180°, etc., closing on south at 0° or 360°.

These two co-ordinates, the altitude and azimuth, will determine the
position of any object with reference to the observer's place. The
latter's position is usually given by his latitude and longitude
referred to the equator and some standard meridian as co-ordinates.

The _latitude_ being the angular distance north or south of the equator,
and the _longitude_ east or west of the assumed meridian.

We are now prepared to prove that _the altitude of the pole is equal to
the latitude of the place of observation_.

Let H P Z Q¹, etc., Fig. 2, represent a meridian section of the sphere,
in which P is the north pole and Z the place of observation, then H H¹
will be the horizon, Q Q¹ the equator, H P will be the altitude of P,
and Q¹ Z the latitude of Z. These two arcs are equal, for H C Z = P C
Q¹ = 90°, and if from these equal quadrants the common angle P C Z be
subtracted, the remainders H C P and Z C Q¹, will be equal.

To _determine the altitude of the pole_, or, in other words, _the
latitude of the place_.

Observe the altitude of the pole star _when on the meridian_, either
above or below the pole, and from this observed altitude corrected for
refraction, subtract the distance of the star from the pole, or its
_polar distance_, if it was an upper transit, or add it if a lower.
The result will be the required latitude with sufficient accuracy for
ordinary purposes.

The time of the star's being on the meridian can be determined with
sufficient accuracy by a mere inspection of the heavens. The refraction
is _always negative_, and may be taken from the table appended by
looking up the amount set opposite the observed altitude. Thus, if the
observer's altitude should be 40° 39' the nearest refraction 01' 07",
should be subtracted from 40° 37' 00", leaving 40° 37' 53" for the


As we have shown the azimuth of Polaris to be a function of the
latitude, and as the latitude is now known, we may proceed to find the
required azimuth. For this purpose we have a right-angled spherical
triangle, Z S P, Fig. 4, in which Z is the place of observation, P the
north pole, and S is Polaris. In this triangle we have given the polar
distance, P S = 10° 19' 13"; the angle at S = 90°; and the distance Z
P, being the complement of the latitude as found above, or 90°--L.
Substituting these in the formula for the azimuth, we will have sin. Z =
sin. P S / sin P Z or sin. of Polar distance / sin. of co-latitude, from
which, by assuming different values for the co-latitude, we compute the
following table:


|      |         |          |         |         |         |         |
| Year |   26°   |   28°    |   30°   |   32°   |   34°   |   36°   |
|      |         |          |         |         |         |         |
|      | ° '  "  | ° '  "   | ° '  "  | ° '  "  | ° '  "  | ° '  "  |
| 1882 | 1 28 05 | 1 29 40  | 1 31 25 | 1 33 22 | 1 35 30 | 1 37 52 |
| 1883 | 1 27 45 | 1 29 20  | 1 31 04 | 1 33 00 | 1 35 08 | 1 37 30 |
| 1884 | 1 27 23 | 1 28 57  | 1 30 41 | 1 32 37 | 1 34 45 | 1 37 05 |
| 1885 | 1 27 01 | 1 28 35½ | 1 30 19 | 1 32 14 | 1 34 22 | 1 36 41 |
| 1886 | 1 26 39 | 1 28 13  | 1 29 56 | 1 31 51 | 1 33 57 | 1 36 17 |
|      |         |          |         |         |         |         |
| Year |   38°   |   40°    |   42°   |   44°   |   46°   |   48°   |
|      |         |          |         |         |         |         |
|      | ° '  "  | ° '  "   | ° '  "  | ° '  "  | ° '  "  | ° '  "  |
| 1882 | 1 40 29 | 1 43 21  | 1 46 33 | 1 50 05 | 1 53 59 | 1 58 20 |
| 1883 | 1 40 07 | 1 42 58  | 1 46 08 | 1 49 39 | 1 53 34 | 1 57 53 |
| 1884 | 1 39 40 | 1 42 31  | 1 45 41 | 1 49 11 | 1 53 05 | 1 57 23 |
| 1885 | 1 39 16 | 1 42 07  | 1 45 16 | 1 48 45 | 1 52 37 | 1 56 54 |
| 1886 | 1 38 51 | 1 41 41  | 1 44 49 | 1 48 17 | 1 52 09 | 1 56 24 |
|      |         |
| Year |   50°   |
|      |         |
|      | ° '  "  |
| 1882 | 2 03 11 |
| 1883 | 2 02 42 |
| 1884 | 2 02 11 |
| 1885 | 2 01 42 |
| 1886 | 2 01 11 |

An analysis of this table shows that the azimuth this year (1882)
increases with the latitude from 1° 28' 05" at 26° north, to 2° 3' 11"
at 50° north, or 35' 06". It also shows that the azimuth of Polaris at
any one point of observation decreases slightly from year to year. This
is due to the increase in declination, or decrease in the star's polar
distance. At 26° north latitude, this annual decrease in the azimuth
is about 22", while at 50° north, it is about 30". As the variation in
azimuth for each degree of latitude is small, the table is only computed
for the even numbered degrees; the intermediate values being readily
obtained by interpolation. We see also that an error of a few minutes of
latitude will not affect the result in finding the meridian, e.g., the
azimuth at 40° north latitude is 1° 43' 21", that at 41° would be 1° 44'
56", the difference (01' 35") being the correction for one degree of
latitude between 40° and 41°. Or, in other words, an error of one degree
in finding one's latitude would only introduce an error in the azimuth
of one and a half minutes. With ordinary care the probable error of the
latitude as determined from the method already described need not exceed
a few minutes, making the error in azimuth as laid off on the arc of an
ordinary transit graduated to single minutes, practically zero.


|           |              |           |              |
| Apparent  | Refraction   | Apparent  | Refraction   |
| Altitude. | _minus_.     | Altitude. | _minus_.     |
|           |              |           |              |
|    25°    | 0° 2' 4.2"   |    38°    | 0° 1' 14.4"  |
|    26     |    1 58.8    |    39     |    1  11.8   |
|    27     |    1 53.8    |    40     |    1   9.3   |
|    28     |    1 49.1    |    41     |    1   6.9   |
|    29     |    1 44.7    |    42     |    1   4.6   |
|    30     |    1 40.5    |    43     |    1   2.4   |
|    31     |    1 36.6    |    44     |    0   0.3   |
|    32     |    1 33.0    |    45     |    0  58.1   |
|    33     |    1 29.5    |    46     |    0  56.1   |
|    34     |    1 26.1    |    47     |    0  54.2   |
|    35     |    1 23.0    |    48     |    0  52.3   |
|    36     |    1 20.0    |    49     |    0  50.5   |
|    37     |    1 17.1    |    50     |    0  48.8   |


In practice to find the true meridian, two observations must be made at
intervals of six hours, or they may be made upon different nights. The
first is for latitude, the second for azimuth at elongation.

To make either, the surveyor should provide himself with a good transit
with vertical arc, a bull's eye, or hand lantern, plumb bobs, stakes,
etc.[1] Having "set up" over the point through which it is proposed to
establish the meridian, at a time when the line joining Polaris and
Alioth is nearly vertical, level the telescope by means of the attached
level, which should be in adjustment, set the vernier of the vertical
arc at zero, and take the reading. If the pole star is about making its
_upper_ transit, it will rise gradually until reaching the meridian as
it moves westward, and then as gradually descend. When near the highest
part of its orbit point the telescope at the star, having an assistant
to hold the "bull's eye" so as to reflect enough light down the tube
from the object end to illumine the cross wires but not to obscure the
star, or better, use a perforated silvered reflector, clamp the tube in
this position, and as the star continues to rise keep the _horizontal_
wire upon it by means of the tangent screw until it "rides" along this
wire and finally begins to fall below it. Take the reading of the
vertical arc and the result will be the observed altitude.

[Footnote 1: A sextant and artificial horizon may be used to find the
_altitude_ of a star. In this case the observed angle must be divided by


It is a little more accurate to find the altitude by taking the
complement of the observed zenith distance, if the vertical arc has
sufficient range. This is done by pointing first to Polaris when at
its highest (or lowest) point, reading the vertical arc, turning the
horizontal limb half way around, and the telescope over to get another
reading on the star, when the difference of the two readings will be the
_double_ zenith distance, and _half_ of this subtracted from 90° will be
the required altitude. The less the time intervening between these two
pointings, the more accurate the result will be.

Having now found the altitude, correct it for refraction by subtracting
from it the amount opposite the observed altitude, as given in the
refraction table, and the result will be the latitude. The observer must
now wait about six hours until the star is at its western elongation,
or may postpone further operations for some subsequent night. In the
meantime he will take from the azimuth table the amount given for his
date and latitude, now determined, and if his observation is to be made
on the western elongation, he may turn it off on his instrument, so
that when moved to zero, _after_ the observation, the telescope will be
brought into the meridian or turned to the right, and a stake set by
means of a lantern or plummet lamp.


It is, of course, unnecessary to make this correction at the time of
observation, for the angle between any terrestrial object and the star
may be read and the correction for the azimuth of the star applied at
the surveyor's convenience. It is always well to check the accuracy of
the work by an observation upon the other elongation before putting in
permanent meridian marks, and care should be taken that they are not
placed near any local attractions. The meridian having been established,
the magnetic variation or declination may readily be found by setting
an instrument on the meridian and noting its bearing as given by the
needle. If, for example, it should be north 5° _east_, the variation is
west, because the north end of the needle is _west_ of the meridian, and
_vice versa_.

_Local time_ may also be readily found by observing the instant when the
sun's center[1] crosses the line, and correcting it for the equation of
time as given above--the result is the true or mean solar time. This,
compared with the clock, will show the error of the latter, and by
taking the difference between the local lime of this and any other
place, the difference of longitude is determined in hours, which can
readily be reduced to degrees by multiplying by fifteen, as 1 h. = 15°.

[Footnote 1: To obtain this time by observation, note the instant of
first contact of the sun's limb, and also of last contact of same, and
take the mean.]


    |          |            |
    |   Date.  |  Minutes.  |
    |          |            |
    | Jan.   1 |        4   |
    |        3 |        5   |
    |        5 |        6   |
    |        7 |        7   |
    |        9 |        8   |
    |       12 |        9   |
    |       15 |       10   |
    |       18 |       11   |
    |       21 |       12   |
    |       25 |       13   |
    |       31 |       14   |
    | Feb.  10 |       15   |
    |       21 |       14   |  Clock
    |       27 |       13   |  faster
    | M'ch   4 |       12   |  than
    |        8 |       11   |  sun.
    |       12 |       10   |
    |       15 |        9   |
    |       19 |        8   |
    |       22 |        7   |
    |       25 |        6   |
    |       28 |        5   |
    | April  1 |        4   |
    |        4 |        3   |
    |        7 |        2   |
    |       11 |        1   |
    |       15 |        0   |
    |          |------------|
    |       19 |        1   |
    |       24 |        2   |
    |       30 |        3   |
    | May   13 |        4   |  Clock
    |       29 |        3   |  slower.
    | June   5 |        2   |
    |       10 |        1   |
    |       15 |        0   |
    |          |------------|
    |       20 |        1   |
    |       25 |        2   |
    |       29 |        3   |
    | July   5 |        4   |
    |       11 |        5   |
    |       28 |        6   |  Clock
    | Aug.   9 |        5   |  faster.
    |       15 |        4   |
    |       20 |        3   |
    |       24 |        2   |
    |       28 |        1   |
    |       31 |        0   |
    |          |------------|
    | Sept.  3 |        1   |
    |        6 |        2   |
    |        9 |        3   |
    |       12 |        4   |
    |       15 |        5   |
    |       18 |        6   |
    |       21 |        7   |
    |       24 |        8   |
    |       27 |        9   |
    |       30 |       10   |
    | Oct.   3 |       11   |
    |        6 |       12   |
    |       10 |       13   |
    |       14 |       14   |
    |       19 |       15   |
    |       27 |       16   |  Clock
    | Nov.  15 |       15   |  slower.
    |       20 |       14   |
    |       24 |       13   |
    |       27 |       12   |
    |       30 |       11   |
    | Dec.   2 |       10   |
    |        5 |        9   |
    |        7 |        8   |
    |        9 |        7   |
    |       11 |        6   |
    |       13 |        5   |
    |       16 |        4   |
    |       18 |        3   |
    |       20 |        2   |
    |       22 |        1   |
    |       24 |        0   |
    |          |------------|
    |       26 |        1   |
    |       28 |        2   |  Clock
    |       30 |        3   |  faster.

       *       *       *       *       *


The collections of the Museum of Natural History of Paris have just been
enriched with a magnificent, perfectly adult specimen of a species of
bird that all the scientific establishments had put down among their
desiderata, and which, for twenty years past, has excited the curiosity
of naturalists. This species, in fact, was known only by a few caudal
feathers, of which even the origin was unknown, and which figured in the
galleries of the Jardin des Plantes under the name of _Argus ocellatus_.
This name was given by J. Verreaux, who was then assistant naturalist at
the museum. It was inscribed by Prince Ch. L. Bonaparte, in his Tableaux
Paralléliques de l'Ordre des Gallinaces, as _Argus giganteus_, and a
few years later it was reproduced by Slater in his Catalogue of the
Phasianidæ, and by Gray is his List of the Gallinaceæ. But it was not
till 1871 and 1872 that Elliot, in the Annals and Magazine of Natural
History, and in a splendid monograph of the Phasianidæ, pointed out
the peculiarities that were presented by the feathers preserved at the
Museum of Paris, and published a figure of them of the natural size.

The discovery of an individual whose state of preservation leaves
nothing to be desired now comes to demonstrate the correctness of
Verreaux's, Bonaparte's, and Elliot's suppositions. This bird, whose
tail is furnished with feathers absolutely identical with those that
the museum possessed, is not a peacock, as some have asserted, nor an
ordinary Argus of Malacca, nor an argus of the race that Elliot named
_Argus grayi_, and which inhabits Borneo, but the type of a new genus of
the family Phasianidæ. This Gallinacean, in fact, which Mr. Maingonnat
has given up to the Museum of Natural History, has not, like the common
Argus of Borneo, excessively elongated secondaries; and its tail is not
formed of normal rectrices, from the middle of which spring two very
long feathers, a little curved and arranged like a roof; but it consists
of twelve wide plane feathers, regularly tapering, and ornamented with
ocellated spots, arranged along the shaft. Its head is not bare, but is
adorned behind with a tuft of thread-like feathers; and, finally, its
system of coloration and the proportions of the different parts of its
body are not the same as in the common argus of Borneo. There is reason,
then, for placing the bird, under the name of _Rheinardius ocellatus_,
in the family Phasianidæ, after the genus _Argus_ which it connects,
after a manner, with the pheasants properly so-called. The specific name
_ocellatus_ has belonged to it since 1871, and must be substituted for
that of _Rheinardi_.

The bird measures more than two meters in length, three-fourths of which
belong to the tail. The head, which is relatively small, appears to be
larger than it really is, owing to the development of the piliform tuft
on the occiput, this being capable of erection so as to form a crest
0.05 to 0.06 of a meter in height. The feathers of this crest are
brown and white. The back and sides of the head are covered with downy
feathers of a silky brown and silvery gray, and the front of the neck
with piliform feathers of a ruddy brown. The upper part of the body is
of a blackish tint and the under part of a reddish brown, the whole
dotted with small white or _café-au-lait_ spots. Analogous spots are
found on the wings and tail, but on the secondaries these become
elongated, and tear-like in form. On the remiges the markings are quite
regularly hexagonal in shape; and on the upper coverts of the tail
and on the rectrices they are accompanied with numerous ferruginous
blotches, some of which are irregularly scattered over the whole surface
of the vane, while others, marked in the center with a blackish spot,
are disposed in series along the shaft and resemble ocelli. This
similitude of marking between the rectrices and subcaudals renders the
distinction between these two kinds of feathers less sharp than in many
other Gallinaceans, and the more so in that two median rectrices are
considerably elongated and assume exactly the aspect of tail feathers.

[Illustration: THE OCELLATED PHEASANT (_Rheinardius ocellatus_).]

The true rectrices are twelve in number. They are all absolutely plane,
all spread out horizontally, and they go on increasing in length
from the exterior to the middle. They are quite wide at the point of
insertion, increase in diameter at the middle, and afterward taper to
a sharp point. Altogether they form a tail of extraordinary length and
width which the bird holds slightly elevated, so as to cause it to
describe a graceful curve, and the point of which touches the soil. The
beak, whose upper mandible is less arched than that of the pheasants,
exactly resembles that of the arguses. It is slightly inflated at the
base, above the nostrils, and these latter are of an elongated-oval
form. In the bird that I have before me the beak, as well as the feet
and legs, is of a dark rose-color. The legs are quite long and are
destitute of spurs. They terminate in front in three quite delicate
toes, connected at the base by membranes, and behind in a thumb that is
inserted so high that it scarcely touches the ground in walking. This
magnificent bird was captured in a portion of Tonkin as yet unexplored
by Europeans, in a locality named Buih-Dinh, 400 kilometers to the south
of Hué.--_La Nature_.

       *       *       *       *       *


The Maidenhair tree--Gingkgo biloba--of which we give an illustration,
is not only one of our most ornamental deciduous trees, but one of the
most interesting. Few persons would at first sight take it to be a
Conifer, more especially as it is destitute of resin; nevertheless,
to that group it belongs, being closely allied to the Yew, but
distinguishable by its long-stalked, fan-shaped leaves, with numerous
radiating veins, as in an Adiantum. These leaves, like those of the
larch but unlike most Conifers, are deciduous, turning of a pale yellow
color before they fall. The tree is found in Japan and in China, but
generally in the neighborhood of temples or other buildings, and is, we
believe, unknown in a truly wild state. As in the case of several other
trees planted in like situations, such as Cupressus funebris, Abies
fortunei, A. kæmpferi, Cryptomeria japonica, Sciadopitys verticillata,
it is probable that the trees have been introduced from Thibet, or
other unexplored districts, into China and Japan. Though now a solitary
representative of its genus, the Gingkgo was well represented in the
coal period, and also existed through the secondary and tertiary epochs,
Professor Heer having identified kindred specimens belonging to sixty
species and eight genera in fossil remains generally distributed through
the northern hemisphere. Whatever inference we may draw, it is at least
certain that the tree was well represented in former times, if now it
be the last of its race. It was first known to Kæmpfer in 1690, and
described by him in 1712, and was introduced into this country in the
middle of the eighteenth century. Loudon relates a curious tale as
to the manner in which a French amateur became possessed of it. The
Frenchman, it appears, came to England, and paid a visit to an English
nurseryman, who was the possessor of five plants, raised from Japanese
seeds. The hospitable Englishman entertained the Frenchman only too
well. He allowed his commercial instincts to be blunted by wine, and
sold to his guest the five plants for the sum of 25 guineas. Next
morning, when time for reflection came, the Englishman attempted to
regain one only of the plants for the same sum that the Frenchman had
given for all five, but without avail. The plants were conveyed to
France, where as each plant had cost about 40 crowns, _ecus_, the tree
got the name of _arbre a quarante ecus_. This is the story as given by
Loudon, who tells us that Andre Thouin used to relate the fact in his
lectures at the Jardin des Plantes, whether as an illustration of the
perfidy of Albion is not stated.

The tree is dioecious, bearing male catkins on one plant, female on
another. All the female trees in Europe are believed to have originated
from a tree near Geneva, of which Auguste Pyramus de Candolle secured
grafts, and distributed them throughout the Continent. Nevertheless, the
female tree is rarely met with, as compared with the male; but it is
quite possible that a tree which generally produces male flowers only
may sometimes bear female flowers only. We have no certain evidence of
this in the case of the Gingkgo, but it is a common enough occurrence in
other dioecious plants, and the occurrence of a fruiting specimen near
Philadelphia, as recently recorded by Mr. Meehan, may possibly be
attributed to this cause.

The tree of which we give a figure is growing at Broadlands, Hants, and
is about 40 feet in height, with a trunk that measures 7 feet in girth
at 3 feet from the ground, with a spread of branches measuring 45 feet.
These dimensions have been considerably exceeded in other cases. In 1837
a tree at Purser's Cross measured 60 feet and more in height. Loudon
himself had a small tree in his garden at Bayswater on which a female
branch was grafted. It is to be feared that this specimen has long since

We have already alluded to its deciduous character, in which it is
allied to the larch. It presents another point of resemblance both to
the larch and the cedar in the short spurs upon which both leaves and
male catkins are borne, but these contracted branches are mingled with
long extension shoots; there seems, however, no regular alternation
between the short and the long shoots, at any rate the _rationale_ of
their production is not understood, though in all probability a little
observation of the growing plant would soon clear the matter up.

The fruit is drupaceous, with a soft outer coat and a hard woody shell,
greatly resembling that of a Cycad, both externally and internally.
Whether the albumen contains the peculiar "corpuscles" common to Cycads
and Conifers, we do not for certain know, though from the presence of 2
to 3 embryos in one seed, as noted by Endlicher, we presume this is the
case. The interest of these corpuscles, it may be added, lies in the
proof of affinity they offer between Conifers and the higher Cryptogams,
such as ferns and lycopods--an affinity shown also in the peculiar
venation of the Gingkgo. Conifers are in some degree links between
ordinary flowering plants and the higher Cryptogams, and serve to
connect in genealogical sequence groups once considered quite distinct.
In germination the two fleshy cotyledons of the Gingkgo remain within
the shell, leaving the three-sided plumule to pass upward; the young
stem bears its leaves in threes.

We have no desire to enter further upon the botanical peculiarities of
this tree; enough if we have indicated in what its peculiar interest
consists. We have only to add that in gardens varieties exist some with
leaves more deeply cut than usual, others with leaves nearly entire, and
others with leaves of a golden-yellow color.--_Gardeners' Chronicle_.


       *       *       *       *       *


A collection of woods without a parallel in the world is now being
prepared for exhibition by the Directors of the American Museum of
Natural History. Scattered about the third floor of the Arsenal, in
Central Park, lie 394 logs, some carefully wrapped in bagging,
some inclosed in rough wooden cases, and others partially sawn
longitudinally, horizontally, and diagonally. These logs represent all
but 26 of the varieties of trees indigenous to this country, and
nearly all have a greater or less economic or commercial value. The 26
varieties needed to complete the collection will arrive before winter
sets in, a number of specimens being now on their way to this city from
the groves of California. Mr. S. D. Dill and a number of assistants are
engaged in preparing the specimens for exhibition. The logs as they
reach the workroom are wrapped in bagging and inclosed in cases, this
method being used so that the bark, with its growth of lichens and
delicate exfoliations, shall not be injured while the logs are in
process of transportation from various parts of the country to this
city. The logs are each 6 feet in length, and each is the most perfect
specimen of its class that could be found by the experts employed in
making the collection. With the specimens of the trees come to the
museum also specimens of the foliage and the fruits and flowers of the
tree. These come from all parts of the Union--from Alaska on the north
to Texas on the south, from Maine on the east to California on the
west--and there is not a State or Territory in the Union which has not a
representative in this collection of logs. On arrival here the logs are
green, and the first thing in the way of treatment after their arrival
is to season them, a work requiring great care to prevent them from
"checking," as it is technically called, or "season cracking," as the
unscientific term the splitting of the wood in radiating lines during
the seasoning process. As is well known, the sap-wood of a tree seasons
much more quickly than does the heart of the wood. The prevention of
this splitting is very necessary in preparing these specimens for
exhibition, for when once the wood has split its value for dressing for
exhibition is gone. A new plan to prevent this destruction of specimens
is now being tried with some success under the direction of Prof.
Bickmore, superintendent of the museum. Into the base of the log and
alongside the heart a deep hole is bored with an auger. As the wood
seasons this hole permits of a pressure inward and so has in many
instances doubtless saved valuable specimens. One of the finest in the
collection, a specimen of the persimmon tree, some two feet in diameter,
has been ruined by the seasoning process. On one side there is a huge
crack, extending from the top to the bottom of the log, which looks as
though some amateur woodman had attempted to split it with an ax and
had made a poor job of it. The great shrinking of the sap-wood of the
persimmon tree makes the wood of but trifling value commercially.
It also has a discouraging effect upon collectors, as it is next to
impossible to cure a specimen, so that all but this one characteristic
of the wood can be shown to the public in a perfect form.

Before the logs become thoroughly seasoned, or their lines of growth at
all obliterated, a diagram of each is made, showing in accordance with
a regular scale the thickness of the bark, the sap-wood, and the heart.
There is also in this diagram a scale showing the growth of the tree
during each year of its life, these yearly growths being regularly
marked about the heart of the tree by move or less regular concentric
circles, the width of which grows smaller and smaller as the tree grows
older. In this connection attention may be called to a specimen in the
collection which is considered one of the most remarkable in the world.
It is not a native wood, but an importation, and the tree from which
this wonderful slab is cut is commonly known as the "Pride of India."
The heart of this particular tree was on the port side, and between it
and the bark there is very little sap-wood, not more than an inch.
On the starbord side, so to speak, the sap-wood has grown out in an
abnormal manner, and one of the lines indicative of a year's growth is
one and seven-eighths inches in width, the widest growth, many experts
who have seen the specimen say, that was ever recorded. The diagrams
referred to are to be kept for scientific uses, and the scheme of
exhibition includes these diagrams as a part of the whole.

After a log has become seasoned it is carefully sawed through the center
down about one-third of its length. A transverse cut is then made and
the semi-cylindrical section thus severed from the log is removed. The
upper end is then beveled. When a log is thus treated the inspector can
see the lower two-thirds presenting exactly the same appearance it did
when growing in the forest. The horizontal cut, through the sap-wood
and to the center of the heart, shows the life lines of the tree, and
carefully planed as are this portion, the perpendicular and the beveled
sections, the grain of the wood can thus be plainly seen. That these may
be made even more valuable to the architect and artisan, the right half
of this planed surface will be carefully polished, and the left half
left in the natural state. This portion of the scheme of treatment is
entirely in the interests of architects and artisans, and it is expected
by Prof. Bickmore that it will be the means of securing for some kinds
of trees, essentially of American growth, and which have been virtually
neglected, an important place in architecture and in ornamental
wood-work, and so give a commercial value to woods that are now of
comparatively little value.

Among the many curious specimens in the collection now being prepared
for exhibition, one which will excite the greatest curiosity is a
specimen of the honey locust, which was brought here from Missouri.
The bark is covered with a growth of thorns from one to four inches
in length, sharp as needles, and growing at irregular intervals. The
specimen arrived here in perfect condition, but, in order that it might
be transported without injury, it had to be suspended from the roof of
a box car, and thus make its trip from Southern Missouri to this city
without change. Another strange specimen in the novel collection is a
portion of the Yucca tree, an abnormal growth of the lily family. The
trunk, about 2 feet in diameter, is a spongy mass, not susceptible of
treatment to which the other specimens are subjected. Its bark is an
irregular stringy, knotted mass, with porcupine-quill-like leaves
springing out in place of the limbs that grow from all well-regulated
trees. One specimen of the yucca was sent to the museum two years ago,
and though the roots and top of the tree were sawn off, shoots sprang
out, and a number of the handsome flowers appeared. The tree was
supposed to be dead and thoroughly seasoned by this Fall, but now, when
the workmen are ready to prepare it for exhibition, it has shown new
life, new shoots have appeared, and two tufts of green now decorate the
otherwise dry and withered log, and the yucca promises to bloom again
before the winter is over. One of the most perfect specimens of the
Douglass spruce ever seen is in the collection, and is a decided
curiosity. It is a recent arrival from the Rocky Mountains. Its bark,
two inches or more in thickness, is perforated with holes reaching to
the-sap-wood. Many of these contain acorns, or the remains of acorns,
which have been stored there by provident woodpeckers, who dug the holes
in the bark and there stored their winter supply of food. The oldest
specimen in the collection is a section of the _Picea engelmanni_, a
species of spruce growing in the Rocky Mountains at a considerable
elevation above the sea. The specimen is 24 inches in diameter, and the
concentric circles show its age to be 410 years. The wood much resembles
the black spruce, and is the most valuable of the Rocky Mountain
growths. A specimen of the nut pine, whose nuts are used for food by the
Indians, is only 15 inches in diameter, and yet its life lines show its
age to be 369 years. The largest specimen yet received is a section of
the white ash, which is 46 inches in diameter and 182 years old. The
next largest specimen is a section of the _Platanus occidentalis_,
variously known in commerce as the sycamore, button-wood, or plane tree,
which is 42 inches in diameter and only 171 years of age. Specimens of
the redwood tree of California are now on their way to this city from
the Yosemite Valley. One specimen, though a small one, measures 5 feet
in diameter and shows the character of the wood. A specimen of
the enormous growths of this tree was not secured because of the
impossibility of transportation and the fact that there would be no room
in the museum for the storage of such a specimen, for the diameter of
the largest tree of the class is 45 feet and 8 inches, which represents
a circumference of about 110 feet. Then, too, the Californians object to
have the giant trees cut down for commercial, scientific, or any other

To accompany these specimens of the woods of America, Mr. Morris K.
Jesup, who has paid all the expense incurred in the collection of
specimens, is having prepared as an accompanying portion of the
exhibition water color drawings representing the actual size, color,
and appearance of the fruit, foliage, and flowers of the various trees.
Their commercial products, as far as they can be obtained, will also be
exhibited, as, for instance, in the case of the long-leaved pine, the
tar, resin, and pitch, for which it is especially valued. Then, too, in
an herbarium the fruits, leaves, and flowers are preserved as nearly as
possible in their natural state. When the collection is ready for public
view next spring it will be not only the largest, but the only complete
one of its kind in the country. There is nothing like it in the world,
as far as is known; certainly not in the royal museums of England,
France, or Germany.

Aside from the value of the collection, in a scientific way, it is
proposed to make it an adjunct to our educational system, which requires
that teachers shall instruct pupils as to the materials used for food
and clothing. The completeness of the exhibition will be of great
assistance also to landscape gardeners, as it will enable them to lay
out private and public parks so that the most striking effects of
foliage may be secured. The beauty of these effects can best be seen in
this country in our own Central Park, where there are more different
varieties and more combinations for foliage effects than in any other
area in the United States. To ascertain how these effects are obtained
one now has to go to much trouble to learn the names of the trees. With
this exhibition such information can be had merely by observation, for
the botanical and common names of each specimen will be attached to
it. It will also be of practical use in teaching the forester how to
cultivate trees as he would other crops. The rapid disappearance of
many valuable forest trees, with the increase in demand and decrease in
supply, will tend to make the collection valuable as a curiosity in
the not far distant future as representing the extinct trees of the
country.--_N.Y. Times_.

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