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THE

PHILOSOPHICAL MAGAZINE.

dor,

COMPREHENDING

THE VARIOUS BRANCHES OF SCIENCE,
THE LIBERAL AND FINE ARTS, '
AGRICULTURE, MANUFACTURES,

Way Boe
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COMMERCE.

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BY ALEXANDER TILLOCH,

MEMBER OF THE LONDON PHILOSOPHICAL SOCIETY. 7 OF

** Nec aranearum fane textus ideo melior, quia ex fe fila gignunt. Nec nofter~
vilior quia ex alienis libamus ut apes.” Jusr. Lirs. Monit. Polit, lib. i, cap. 1--

LONDON:

Printed for the Proprieroxs: And fold by Meffrs, Ricuarpson,
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St. James's-ftreet ; J. Remnant, High-ftreet,
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Pe BAG EB.

Havinc concluded our Firft Volume, we
would be deiicient in gratitude did we not return
thanks to the Public, in general, for the favourable
reception our labours have experienced; and to
thofe Scientific Gentlemen, in particular, who have
affifted us with Communications, as well as Hints

refpecting the future conduéting of the Work.

As the grand Object of it is to diffufe Philofo-
phical Knowledge among every Clafs of Society,
and to give the Public as early an Account as pof-
fible of every thing new or curious in the fcientific
World, both at Home and on the Continent, we
flatter ourfelves. with the hope that the fame liberal
Patronage we have hitberto experienced will be
‘continued; and that Scientific Men will afford us
that Support and Affiftance which they may think
our Attempt entitled to. Whatever may be our
future Succefs, no Exertions fhall be wanting on our
part to render the Work ufeful to Society, and efpe-
cially to the Arts and Manufa@tures of Great Britain
which, as is well known, have been much improved.
by the great Progrefs that has lately been made in
- vatious Branches of the Philofophical Sciences.

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CONTENTS

OF THE

FIRST VOLUME.

“Page
ACCOUNT of Mr. Cartwright’s Patent Steam Engine i
The Genuine Oriental Proce/s for giving to Cotion Yarn, or
Stuffs, the faft or ingrained Colour, known by the Namie ©
| Turkey or Atrianople-Red. By Profeffor PALLAS 4.
Method of purifying Lead from Gold and Silver, fo as to make
it fit for the Purpofe of Affaying. By P.J. HseELM 11
On the Irregularity in the Rate of Going of Time- Pieces, oc-
' cafioned by the Influence of Magnetifm. By Mr. VaRLBY 16
Method of preparing a cheap Subjtitute for Oil Paint. By
_ M. LupicKke ~ - - - = 22
On the Antiquity and Advantages of Encauftic Painting, with
an Examination of the Procefs employed in that Art by the
Ancients. By M. FABBRONI - - = 29% LAr
Method of difcovering whether Wine bas been adulterated
with any Metals prejudicial to Health, By M. Han-
HEMAN - = . = 40 FE
On the Solar and Lunar Period of 600 Years. By Profefion
BurJa = re - u - 32
On the Irritability of Sea Sponges. By Profeffor PALLAS 34
On the Theory of the Structure of Cryftals. By the Abbe
Havuy z : - 35» 153, 2875 376
Obfervations on Iron and Sieel. By Mr. CoLuieR - 46
Account of a Violet Dye, produced from the Leaves of Succotrine
Aloes. By M. FABBRONI - - = 56
A curfory View of fome late Difcoveries and Inprovements in
different Branches of Science = 59, 208, 305,421
An Account of two fingular Meteors lately. jeen in Prance 66
Ona new Acid procured from Animal Sudjiances, called the
' Zoontc Acid. By M. BERTHOULET - - 68
Biographical Memoirs of the late Protefior NisuwLAND 69
Defcripiion of Mr. DesVignes’s improved Apparatus for making
Artificial Mineral Waters - - = 7
Extrait from a Memsire on a new Metal called Tellurium.
By Profeflor KLAPROTH pie ar wp As:

Some

i CH. TE NTS
Some curiovs Circumflances refpeciing the two Elephants tem
moved to Paris from the Hague - § = page 8
Some Particuiars refpeciing the Embafly of the Dutch Eajt
India Company to the Court of Pekin, mm 1494 and 1795s
extracied jrom M. VAN Br&am’s Journal - -
Chemical Experiments to render Paper and the Writings ti
on indefiructible by Fire. By M. BRUGNATELLI 8g, 1
Report of D. Dominie Garcia lernandez on a new Wood, called -
Paraguatan, prope 7 for Dyeing - 93
Defcription of the Mechenym of a reflecting Te lefeope ti enty~
fix Feet in Length, conjtrucied near Kiel in Hoiflem. By
Profeflor SCHRADER - 113
Dejfcription of the Javanefe bares which oni udis ealable
Nefis; with an Account of the Manner in which the Nefés
are collected : ATS
The Proce/s followed at t Miraven ‘to give is Cotlon Yarn. a
Blue, Yellow, or Green Dye. By Profeflor PALtLAS 126
Ob/ervations on a Junction of the Red Sea to the Mediterra«

nean = TO
Obfervations on ; ibe Organs of Faken’ in Bats. ae M. Seat-
LANZANI - 134

Experiments on Bats depr ived of Sight by M. DE JURINE 136
An Account of the ** New Method of performing and facili-
tating the Bufinefs of divers bath ak ing and economical
. Proceffes, ” for which a Patent, dated 24th June 14795, was
ranted to SAMUEL BENTHAM, Eq. =e
Method to deftroy or drive away Earth worms ond various
other Infects burt id to Itelds and Gardens. By M. So-
COLOFF - 169
On the Hevterficatien af fame Kinds of Infeets killed in Spirit
of Wine. By M. SocoLorr - > ET
On Teft Liquors for detecing Acids and Alkalis in Chemical
Mixtures. By Mr. Watt - 180
An Account of ‘be Sugar Maple of the United States, by
Benjamin Rusu, M. D. Prof feffer of the Infitutes of
Medicine in the University of Pernfylvania. Communicated
by Ropert Joun THORNTON, M.D. Leétlurer on Me-
dical Botany at.Guy’s Hofpital é awe
An Account of Mr. PARk’s-Journey into the Hiewee Parts of
Africa. rom the ihe © ‘of the African Affociation, ©
1798 ~~ 191," 235
Analy fis of the Poicehh of Bau: By M. VAUQUELIN 204
Biographical Memoirs of PETER BAYEN. By M. Lassus,
Secretary to the Cla/s of the Phy, pitas Scieneis in the French
Nat. Inflitute - 212

Defeription-

CONTENTS. na

Defcription of the large Orang Outang of Borneo. . By
F. B. VON WuRMB - - page 225
Objervaiions ‘on a Jingular Phenomenon called the Spectre of
the Broken. By J. L. JonDAN Syke 232
Explanation of the French Meafures and IVeights, pointing
out tovir Value and principal Ujes, according to the Law of
Germinal 18th, 3d Yeur of the Republic 2 245
Account of Dr. PERKINS’s Difcovery of the Influence of
Metallic Tradiors in removing Difeafes é 250
An Analyfis of the Waters of two Mineral Springs at Le-
mington Priors, near Warwick; encluding _ Experiments
tending to elucidate the Origin of the Muriatic Acid. By
Witiiam Lames, M. A. - 2555 350
Method employed between Melun and Lieufaint in France, to
meafure the Bafe of a Triangle, in order to determine the.

Length of an Are of the Meridian - i 269
Chemical Reflections on the Effect produced by Mordants in
dyeing Cotton red. By J. A. CHAPTAL 2 2

~ . 4
On a new Metallic Subftance contained in the Red Lead -
Siberia, to which it is propofed to give the Name of Chrome,
on account of the Property zt poff{fes of colouring every Sub~
stance combined with it. By M. VAUQUELIN 279
An Account of the Jumping Moufe of Canada. By Major
S General THomaAs Daviess, F.R.S. and L.S. 285
Defcription of the Apparatus employed by LAVOISIER to
produce Water from its component Parts, Oxygen and
Hydrogen - fuel - 303
Defcription of the Apparatus contrived by Mr. CAVALLO for
containing Gas of any Kind, and transferring it to Bottles,
Bladders, &e. - - - 305
On the Effects of Oxygen in accelerating Germination. By
HumeBoit ~ - - 309
On the Invention of the Telegraph, with a Defcription of that
propofed ty Dr. HooKE - - 312
Propofitions refpetting the Mechanical Power of the Wedge,
by Mr. Perer Nicuouson of Newman-fireet 316
Report of the Commiffioners appointed by the National Inftitute
to repeat the Experiments which have been made on Gal-
vanifm - ~ - - 19
Of an Attempt to make the Maple Sugar above an hundred
. Years ago. Communicated by Dr. THORNTON, Leurer
oz Medical Botany at Guy’s Hofpital, Sc. = 322
Obfervations on the Account of the /uppofed Orang Outang of
the Eaft Indies, publifbed in the Tranjadtions of the Bata-
vian Society in the Ifland of Java. By De GEorrroy,
Profelfor of Loology at the Mufcum of Natural Hiftory 337
6count

vit CONTENTS:

Account of the Methods employed t in Japan and China to pre«
pare Soy, with fome Obfervations on the Bean from.whtch

_ itis produced. \ By Proteflor BECKMANN page 342)

Comparative View of the expanfive Force of the ie a
Water and that of Alcohol, By R. Prony Fs

Second Memoir on the Metal contained in the Red Look *
Siberia. By Cit. VAUQUELIN - 361

Propofal for a new Hygrometer. By Mr. Hoows EIMER 367.

Method employed 1 in Spain for making the Alcarrazas, or Vef-
Jels ufed there for cooling Water. By Cit. LASTEYRIE 371

Qua:the Principles of . Equilibrium, and the Stability of Floating
Bodies applicd to River and Canal Boats of di ifjerent Forms.
By Mr. Joun GEORGE aod Teacher of Mathe-
matics and Mechanical sara by. . Communicated by the
- Author

393
New Method of freeing Molaffes ra. their foarp Tafie, and -
98)

rendering them fit to be ufed injlead of Sugar

Défeription and Ufe of the Dynanometer, or Inflrument 3
afcertaining the relative Strength of Men and Animals.
Invented. by Cit. REGNIER 399

Method of filing up Engraving on Silver chieh a durable
Black Exiamel, as pradifed in ‘Perfia and India. Commu-
\ nicated in a Tretto r from Siberia to Profeflor PALLAS 405

Different Methods employed in Encaufiic Painting, according
to:the Principle followed by the ancient Greek and Roman-
Painters, difcovered by the Abbe RrauEno, and fince
praci ifed with much Succe/s at Rome. Communicated by
Mr..Cuarves Heatecore TATHAM, Archite 406+

Chemical cate a on the Rpaheai By J. A. CHAP-
TAL

Of a remarkable Sache eff fled by: the Uje of Carbone ded
Gas, communicated ina Letter to his Excellency Prince
Demetrius de Golitzin, Minifter ¥ the Imperial Court of
Ruffia at the Hague. » M. D. JaAnsEens of thar
hout - \

Extra& of « Memoir on the Po offil Bones of Quadrispedld <By
Cit. Cuvier i

os
Obfervations on the Confliticent Parts of seas Air, By

Count de Morozzo 417
Communication from Dr. TaUawrdn: Lséttiveh on Medical’
Botany at Guy’s Ho ofpital, re/petting a sveppefeg ce Na-

ture, now exhibiting in London - 423

Scientofic Intelligence - - “95s 218, 336, 424 |
325

THE

&

THE

PHILOSOPHICAL MAGAZINE:

ase

y¥UNE 1798.

1. Account of Mr. Car rirricHr’s Patent Steam Engine.

hb we fteam engine 1% confidered, and with juftice, as the
firft mechanical invention of modern times. The parent
idea of this new and ftupendous power originated, it is well
known, in the fertile mind of ihe Marquis of Worcefter, in
the time of the Charles’s; though Captain Savary feems to
have been the firft who a&tually pointed out to the public its
practical application, In his hands, however, it was but
Hercules in the cradle. Newcomen and his affociate have

the merit of bringing it to maturity, and giving to its energies
En = a / oS fo)

.'

’

,
a,
a

a

a valuable ‘direction. The principal improvements that have
been added to it for the aft thirty years, it has received from.
the hand of the juftly celebrated Mr. Waitt. From the
many fruitlefs attempts which have been made fince the date
of Mr. Watt’s patent, ftill further to improve the fteam
engine, the public has been led to believe, either that it has
already arrived at its higheft ftate of perfection, or that its
defects admitted not of remedy. Thefe defe&s, as every
one knows, are an imperfect vacuum, much friction, and a
‘comiplicated conftruétion of parts; liablé, without great care
“and attention, to be frequently out of order. It is to thefe
points Mr. Cartwright has immediately, and, we may add,
fuccefsfully, direéted his attention, His firft obje& feems
“to have been to obtain, as nearly as may be, an abfolute
© Vou, I, B vacuum ;

B} Mr. Cartwright’s Patent Steam Engine.

vacuum; which, in confequence of the elaftic vapour that
feparates from water injeGted in the ufual mode of conden-
fation, no one in the leaft converfant with the philofophy of
the fteam engine need be told is impoffible. The con-
denfation, in Mr. Cartwright’s engine, is performed by the
application of cold to the external furface of the veffel con-
taining the fteam. Mr. Cartwright is not, however, the
firft who tried this method; the fame has been attempted by
feveral; but with fo little fuccefs, that one of our firft
engineers in this line has been heard to give itas his opinion,
that, were a pipe to be laid acrofs the Thames, the condenfa-
tion would not be quick enough to work a fteam éngine
with its full effet. The manner Mr. Cartwright manages
this bufinefs is by admitting the fteam between two metal
cylinders lying one within the other, and having cold water
flowing through the inner one, and enclofing the outer one.
By thefe means a very thin body of fteam is expofed to the
greateft poffible furface. But this is not all: by means of a
valve in the pifton there is aconftant communication at all
times between the condenfer and the cylinder, either above
or below the pifton, fo that, whether it afcends or defcends,
the condenfation is always taking place.

To reduce the friction of the pifton, which, when frefh
packed in the common way, lays a very. heavy load upon the
engine, Mr. Cartwright makes his folely of metal, and ex-
panfive. There is a further advantage in this method, from the
faving of time and expence in the packing, and from the pifton
fitting more accurately, if poffible, the more it is worked.

Mr. Cartwright has been equally attentive in fimplifying
all the other parts of the engine; his engine having only
two valves, and thofe are as nearly felf-acéting as may be.

But what will probably be efteemed one of the moft im-
_portant circumftances attending thefe improvements, is the
opportunity they afford of fubftituting ardent fpirit, either
wholly or in part, in the place of water, for working the
engine, For, as the fluid with which it is worked is made to

aaa g circulate

- Ss 4 eet
—<—

Mr. Cartwright’s Patent Steam Engine. 3

circulate through the engine without mixture or dintinution,
the ufing alcohol, after the firft fupply, can be attended with
little or no expence. Onthe contrary, the advantage will be
great, probably equal to the faving of half the fuel.. When,
indeed, the engine is applied, as Mr. Cartwright occafionally
purpofes, both as a mechanical power and as a ftill at the
fame time, the whole fuel will be faved.

A farther advantage of this invention is its-applicability
to purpofes requiring only a {mall power, and for which any
other engine would be too complicated and expentfive.

Plate I. reprefents a fection of the different parts of the
engine. A is the cylinder, which is fupplied with fteam from
the boiler through the pipe gz. B the pifton, in the act of
going up. I the pipe which conduéts the fteam into C the
condenfer, being a double cylinder, between which the fteam
is condenfed, and from thence paffes through 4 into the pump
D. The pifton D when going down prefles the condenfed
water upon the valve cand fhuts_it, by which means the
water is forced to find a paflage through d into the air box E..
What air or elaftic vapour may have been driven along with
the water into E rifes to the upper part of the box, where
aéting by its clafticity on the furface of the water, the latter,

_ fhutting the valve 4, is forced through the tube Jf; and by this

means returned into the boiler. When the air is colleGted
in fuch quantity as to force the float ¢ to fink to a certain

‘depth, the valve e opens, and allows a portion of it to efcape.

* F the fteam valve is opened by the return of the pifton B,

' which raifes the rod attached to the under fide of F, while

at the fame time the valve G is fhut by its rod being preffed
againft the top of the cylinder. ‘When the pifton B, preffed
down by the fteam introduced from the tube @ through the
valve F, reaches the bottom of the cylinder, the valve G is

_ opened by its rod touching the bottom, while at the fame
_ inftant the {pring fhuts the fteam valve F.

HH two cranks, upon whofe axes are two equal wheels
working in eachother for the purpofe of giving a rectilinear
! Ba direction

4 Oriental Proce/s for dyeing Red.

direétion to the pifton rod. M the box that contains thé
condenfing water, K plan of the pifton, fhewing the metak
rings which by the fprings LL are forced outwardly againft
the infide of the cylinder, fo that the pifton can adapt itfelf to
any inequality that may arife. The pifton rod is alfo made
fteam tight in the fame manner at N, O a part of the fly
wheel which regulates the motion.

~ «

EI. The Genuine Oriental Procefs for giving to Cotton Yarn or
Stuff the fafl or ingrained Colour, known by the Name of
Turkey Red, as pradtifed at Aftracan. From Neue Nor-
diiche Beytrage, by Profeffor PALLAS.

A METHOD of giving a fixed red to cotton yarn, fo
much fought after by the Europeans in the prefent century,
is now known in England, and praétifed in the fouthern
parts of France; but, as it is not univerfally known, and. as
thefe proceffes are not only different, perhaps, from the
oriental method, but, like the one for dyeing cotton with
madder deferibed by Hellot, far inferior to that practifed by
the Armenians at Aftracan, the prefent information may not
be fuperfluous.

Profeffor Oettinger at Tubingen made, long ago, in a
‘mall publication which appeared in 1764, a difcovery which
might have led to the fecret of the oriental procefs fordyeing
with madder. He there remarked that the beautiful dye of
the Turkifh yarn, which withftands the ftrongeft folvents,.
becomes immediately diffolved by common olive oil, in fuch
a manner that the colour may be transferred from a thread
of Turkey yarn to any other undyed thread. Hence it
clearly appears, that either the dye itfelf, or the preparing
liquor (appre), or both, muft be of a fat nature, and foluble
in oil: and an ingenious artift might have built with ad-
vantage on thefe grounds, as will be fufficiently feen by the
following defcription of the oriental procefs employed to dye
with madder, which I here give exactly as it was related to

me,

Oriental Procefs for dyeing Red. 5

me, and I fhall leave the improvement of it to thofe to
whofe department it belongs, and who have a tafte for
technical chemiftry.

The greater part of the filk and cotton manufactories at
Aftracan are carried on by Armenians, the number of whom
on account of the troublefome ftate of Perfia is continually
increafing ; and the dye-houfes are kept going only from the
firft warm days in the {pring till towards the end of autumn.
The madder they employ comes partly by land over Kitzlar
from Terek, and partly by fea over Derbent from the Perfian
Ghilan. In both places the plant grows wild in the fields in
great abundance and great perfection, and is dug up alfo in
the uncultivated meads. The roots are generally as thick as
the barrel of a quill, fometimes as one’s finger, and through-
out the whole fpongy part of an agreeable pale red colour:
the bark on the other hand is for the moft part very thin, and
appears to be of little value. At Terek the frefh gathered
roots are placed above each other in a ftove, or in a pit dug
in vifcous earth which has been ftrongly heated. Earth is
then thrown over the madder, and it muft fweat until the
ftove or pit becomes cold; when the roots, the fecond or
third day, are taken from it, and either fpread out or hung
up to dry. The fame procefs is ufual alfo in Perfia, and
abundance of madder is brought from the remote parts of that
country to Ruffia. At Aftracan itis fold, according to the im-
portation, at ftom four to feven rubles for every forty pounds.

This madder is ground at Aftracan, for the ufe of the
dyers, in horfe-mills kept by the common people, and, con-
firuéted in the following manner: In the middle of the
mill, which is built on a level {pot of ground, a circular place
is walled round with bricks to the height of four fpans, the
inner face of which is made to flope gently from the cir-
cumference towards the centre, and a groove goes round the
- infide of this brick-work to receive the mill-{tone. The
whole furface of the brick-ivork is covered with plane
fmoath boards, and in the middle of it ftands a perpendicular

7B fpindle,

6 Oriental Procefs for dycing Red. -
fpindle, which at the top is inferted in a crofs beam, and at
the bottom refts in a focket. The fpindle is turned by
means of an oblique beam pafling through it, to the fhorter
end of which is faftened a mill-ftone moveable like a wheel
round its axis, and a horfe is yoked to the other end, which
reaches beyond the brick-work. The madder, which has
been well dried in the fun, mutt be firft coarfely broken in
the groove under the mill-ftone, and afterwards ground until
it become a very fine powder.

In the fame mills are ground the round leaves of the
’ fumach (rbus cotenus), which gives a yellow dye, and which
is brought to Aftracan from the neighbourhood of Terek,
where it grows wild under the Tartarian name balga, or, as
the Armenians exprefs it, be/ge, and is employed fometimes
in dyeing with madder, fometimes in dyeing dark yellow, and
fometimes in the preparation of Turkey leather. Thefe
leaves, when whole, have a pleafant green colour; but when
bruifed they exhibit that yellow dye with which they are im-
pregnated, and which is produced alfo by the woody part
and branches: but as thefe are not fo eafily cleaned, they are
carefully feparated from the ground duft of the leaves by
means of a fieve. A pud or forty pounds of thefe leaves, in
the ftate in which they are brought to Aftracan, cofts five,
fix, and often feven and a half rubles.

The dye-ftufls neceflary for dyeing red, befides the two
already mentioned, are gall-nuts, alum, an indigenous had
kind of foda, called kalakar, which is burnt in the wilds of
Kiflar and Aftracan, from the falfuginous or foda plants, that
grow there in abundance, and laftly fith-oil. The latter is
boiled in the fifheries on the lower part of the Volga, and on
the Cafpian fea, from the entrails of the fturgeon and other
large fith, but chiefly from thofe of the perca lucioperca, the
fhad, and other kinds little efteemed in thofe parts. The
proof of its being proper for dyeing is, that when mixed with
a lixivium of foda it muft immediately affume a milky ap-

pearance, Should that not be the cafe, it cannot be ufed by
the,

Oriental Procefs for dyeing Red. 4
-the dyers. The foda is burnt partly at Kiflar by Armenians,
and partly in the wilds of Aftracan by the Calmucks. The
latter, becaufe it is very impure, fells at Aftracan for only fif-
teen copeks per pud, but the former is worth more than thirty.
The cotton to be dyed red is firft wafhed exceedingly clean
in running water, and, when the weather is clear, hung up
on poles to dry. If it does not dry before the evening, it is
taken into the houfe, on account of the faline dews {o re-
markable in the country around Aftracan, and acain expofed
to the air next morning. When it is thoroughly dry it is
Jaid in a tub, and fifh-oil is poured over it till it is entirely
covered. In this ftate it muft ftand all night, but in the
morning it is hung up on poles, and left there the whole
day; and this procefs is repeated for a week, fo that the cot-
ton lies feven nights in oil, and is expofed feven days to the
atmofphere, that it may imbibe the oil and free itfelf from
allair. The yarn is then again carried to a ftream, cleaned
as much as poffible, and hung up on poles to dry.

After this preparation a mordant is made of three mate-
rials, which muft give the grounds of the red colour. The
pulverifed leaves of the fumach are firft boiled in copper
kettles; and when their colouring matter has been fufficiently
extracted fome powdered galls are added, with which the
liquor muft be again boiled; and by thefe means it acquires a
dark dirty colour. After it has been fufficiently boiled the
fire is taken from under the kettle, and alum put into
the ftill hot liquor, where it is foon diffolved. The propor-
"tion of thefe three ingredients I cannot determine with fuf-
ficient accuracy, becaufe the dyers make ufe of different
quantities at pleafure. .The powder of the fumach leaves is
meafured into the kettle with ladles; the water is poured
in according to a gauge, on which marks are made to fhew
how high the water muft ftand in the kettle to foak fix,
eight, ten, &c. puds of cotton yarn. The galls and alum
are added in the quantity of five pounds to each pud of cot-

B4 ton,

8 Oriental Pr ace/s Sor dyeing Red.

ton. In a word, the whole mordant muft be fufficienthy
yellow, ftrong, and of an aftringent tafte.

As foon as the alum is diffolved, no time muft be loft in
order that the mordant may not be fuffered to cool. The
yarn is then put into hollow blocks of wood fhaped like a
mortar, into each of which fuch a quantity of the mordant
has been poured as may be fufhcient to moiften the yarn
without any of it being left. As foon as the workman”
throws the mordant into the mortar, he puts a quantity of
the yarn into it, and preffes it down with his hand till it be-
comes uniformly moiftened, and the whole cotton yarn has
ftruck. By this it acquires only a pale yellow colour, which’
however is durable. It is then hung up on poles in the fun.
to dry; again wafhed in the ftream, and afterwards dried
once more. Aide

By the yellow dye of the fumach leaves, the madder dye
becomes brighter and more agreeable; but the galls damp the.
fuperfluous yellow, and together with the alum prepare the
yarn for its colour, Some dyers however omit the ufe of
thefe leaves altogether, and prepare their mordant from galls
and alum only, by firft boiling the galls in due proportion
with the requifite quantity of water, then diffolving the alum
with boiling water in a feparate veffel, afterwards pouring
both liquors together into a tub, and fuffering the cotton to
remain in them an hour, or an hour and a half; after which
it is dried gradually, then wafhed, and again dried once
more. By this procefs the yarn acquires a dirty. reddifh _
colour. ul

The next part of the procefs is to prepare the madder dye,
The madder, ground to a fine powder, is fpread out in large
troughs, and into each trough is poured a large cup full of
fheep’s blood, which is the kind that can be procured with
the greateft facility by the dycrs. The madder muft be

rongly mixed in it by means of the hand, and then ftand
fome hours in order to be thoroughly foaked by it. The hs °

et

Oriental Procefs for dycing Red.
guor then affumes a dark red CU Aa: and the madder
in boiling yields more dye.

After this procefs water is made hot in large kettles, fixed
in brick-work; and as foon as it is warm the prepared red
dye is put into it, in the proportion of a pound to every
pound of cotton. The dye is then fuffered to boil ftrongly 5
and when itis enough, which may be tried on cotton threads,

‘the fire is removed from under the kettle, and the prepared
cotton is depofited near it, The dyer places himfelf on the:
edge of the brick-work that enclofes the kettle; dips the cot-

ton yarn, piece by piece, into the-dye; turns it round, back-
“wards and forwards ; preffes it a little with his hands; and
Jays each piece, one after the other, in pails ftanding ready
for the purpofe. As foon as all the cotton has received the
firft tint, it is hung up to dry: as the red, however, is full
too dull, the yarn which has been already dyed once, and be-
come dry, is put once more into the dyeing-kettle, and muft
be left there to feethe for three hours over a ftrong fire, by
which it acquires that beautiful dark red colour which is fo
much efteemed in the Turkey yarn. The yarn is now taken
from the dye with fticks ; the fuperfluous dye which adheres
to it is fhaken off; the hanks are put in order, and hung up,
one after another, to dry. When it is thoroughly dry, it is
wafhed in the pure ftream and again dried. The only fault
of the Aftracan dyers is, that the colour is fometimes brighter
and fometimes darker, probably becaufe they do not pay fuf-
ficient attention to the proportions, or becaufe the madder is
not always of.the fame goodnefs.

In the laft place, the abovementioned foda (kalakar) is dif-
folved with boiling water in tubs deftined for that purpofe,
and it is ufual here to allow twenty pounds of foda to forty

ounds of cotton, or half the weight. Large earthen jars,

which are made in Perfia of very ftrong clay, a yard and a
half in height, almoft five {pans wide in ihe belly, and end-
ing in aneck a fpan and a half in diameter, enclofed by
means of cement in brick-work oyer a fire-place, in fuch a

manneg.

10 Oriental Proce/s for dyeing Red.

“manner that the necks only appear, are filled with the dyed
cotton yarn. The ley of diflolved foda, which is blackifh and
very fharp, is then poured over it till the jars be filled; and
fome clean rags are preffed into their mouths, that the up-
permoft fkains of yarn may not lie uncovered. A fire is then
made in the fire-place below, and continued for twenty-four
hours; and in the mean time the fteam which arifes from _
the jars is feen collected among the rags in red drops. By
this boiling the dye is ftill more heightened, and is made to
ftrike completely ; every thing fuperfluous is removed, and all
the fat matter which ftill adheres to the yarn is wafhed out:
nothing more is then neceflary for completing the dye of the
yarn but to rinfe it well feveral times in running water, and
then to dry it.

That the dye of madder might be made very penetrating:
by other methods, and through the means of other oily and
refinous fubftances, is fhewn by the procefs of the Tungufians
to dye horfe’, goat’s and rein-deer’s hair, which they ufe for
ormnamenting their dreffes, of a beautiful red colour, by the
roots of the crofs-wort, or northern madder (gallium), and,
narrow-leaved woodroof (a/perula tinéoria), which have a
refemblance to thofe of madder. They boil the frefh or dried
roots with about the fame quantity of agaric (agaricus offi-
cinarum), which, as is well known, is abundant in refinous
gummy particles, and is ufed by the people of Jakut inftead
of foap; they then lay in it the white hair which they wifh
to dye, and fuffer it to feethe flowly until it be fufficiently
red.

Cotton cloth is dyed with madder at Afiracan in the fame
manner: but many purfue a fraudulent procefs, by dyeing
with red wood, and then fell their cloth as that which has
been dyed in the proper manner.

Nore BY THE EDITOR.
One circumftance in the preceding procefs deferves parti-
cular attention, as it furnifhes a hint which, if properly fol-
lowed

Method to purify Lead for Affaying. Ir
~ lowed up, may perhaps enable our dyers to give to cotton
all, or at leaft a number of the colours which at prefent can
only be communicated to woollen. We allude to the ufe
of fith oil and fheep’s blood, both of which animal fubftances
are confidered as being indifpenfably neceffary to the fuccefs
of the operation.

Mr. Vogler, an able German chemift, after long and fre-
quent trials to give to linen and cotton alafting black colour,,
found that, to gain this end, it was previoufly neceffary to
dip the yarn or ftuff into a folution of glue in water, in fuch
-proportion as to give to the water when warm, being tried
between the fingers, a fticky or glutinous confiftence; and
recommends that care be taken only to wring, not to wath
out the glue-water, part of which muft be allowed to dry
upon the yarn, Profeffor Beckmann has noticed fimilar cir-
cumftances, ;

The inference, as has been obferved by M. Berthollet and
others, is, that to fucceed in giving fome particular fixed
colours to vegetable produétions, it is neceffary that they be
previoufly animalifed, as it were, by the application of oil,
blood, glue, or other animal ‘matter.

TIL. Method of purifying Lead from Gold and Silver, fo as to
make ut fit for the Purpofe of Affaying. By Per. Jac.
HyeLmM. From the New Tranfactions of the Royal Aca-
demy of Sciences at Stockholm.

Ox many occafions, particularly in trying the finenefs of
gold, it is neceffary to employ lead free from the mixture of
any other metal. For fuch experiments, above all, one muft
not make ufe of lead which already contains gold or filver,
or both thefe metals, without knowing the quantity, which,
at all times, occafions difficulty and often uncertainty. In
its natural ftate lead, for the moft part, is found fo mixed

with

a2 Method to purify Lead for Affaying.

with thefe noble metals, that after being fmelted it cannot
be employed for the above purpofe; and though there be
Jead ore which exhibits only a very few or no traces of their
prefence, and in the firft cafe the proportion muft never be
more than a quarter of a grain in the pound (mark), it is
exceedingly rare in the common courfe of mining to find
pieces of fuch a nature, and people often have not leifure to
fearch for them. As I have fometimes been expofed to
great inconvenience for want of a proper piece of lead, I
endeavoured to find out an eafy method of procuring, with-
out a tedious procefs, fuch a quantity of pure lead as would
be fuficient for the before-mentioned teft; and as I do not
temember to have heard of its being any where deferibed or
employed, I have reafon to think that an account of it may
be of fome ufe, at leaft in the art of affaying, in cafe a more
extenfive application of fuch a fmelting procefs be not pof-
fible on a large feale, or if it fhould not be found profitable.
When one begins to reflect on this objeét, the firft idea that
occurs is to accomplifh the end in view, by diflolving the
Jead in an acid, and then precipitating either the lead or the
finer metals ; but on clofer examination there is no procefs
of this kind which will not be either too expenfiye, when it
is neceflary to prepare feveral pounds at once, or require
longer time than one can poflibly beftow. For thefe reafons
J gave up this method, and adhered to that only which was
performed merely by fufing in a crucible with the afliftance
of a requifite degree of heat.

Firft Experiment.

Litharge, a cheap article that can be eafily procured, was
the firft fubftance with which I thought it neceflary to make
experiments. As it feemed poflible that it might be free from
any muxture of filver, that circumftance was firft examined
before I proceeded further.” I then melted fome ounces of
htharge with equal quantities of pot-ath and tartar ; but the
jead obtained from this mixture contained ftill about half a

gral’

Method to purify Lead for Affaying. 13.
grain in the pound. It was therefore of no ufe for proofs by
{eorification and for aflaying; and the principal point now
was to free the litharge from its mixture. This objeét L
accomplifhed by a few meltings, in the following manner :

I placed a crucible, in which half a pound of litharge:
found good room, and which was fitted with a clofe cover,
in a wind-furnace filled with dead coals. I then put into
the crucible a mixture of four ounces of potafh and the
fame quantity of powder of flint. When the whole was
well melted by ftrengthening the draught and making the
coals glow, I took off the cover, and laid hold of the cruci-
ble with a pair of tongs, in order to take it out, and to fuf-
fer this very fufible glafs to cover the infide of the crucible,
to fecure it from the glafs of the lead which I meant to
melt in it. The fuperfluous glafs was poured out; the
crucible again placed on its foot, and half a pound of li-
tharge thrown into it with a fhovel. The cover was placed
upon it while the litharge was melting; and when it was
thoroughly glowing and fluid, charcoal duft was fifted into
the uncovered crucible through a fieve, fo that the furface
of the litharge was completely covered with it. This ims
mediately produced an effervefeence, and the rifing of bub-
bles, by means of the feparation of the air occafioned by
the reduétion of the lead. During this procefs the cover
twas put on and a few coals thrown into the furnace: when
thefe were burnt every thing in the crucible was quiet, and
the melted mafs was poured into a warm conical mould,
The crucible was then again filled with half a pound of
the fame kind of litharge, and put into the furnace, and
charcoal duft was feveral times fifted over the melted fur-
face, till it was well covered before the mafs was thrown
out, a fufficient {pace being every time left for the effervef-
cence. The firft mafs had, in the mean time, become cool,
and, on examination, contained four ounces of lead at the
bottom, and litharge at the top. When this litharge was
reduced with potafh and crude tartar, the lead thence ob«

tained,

14 Method to purify Lead for Affaying.

tained, which weighed 23 ounces, was found to contain lefs
than 3 grain of filver in the pound. In the fecond mafs
there was found fomewhat more than fix ounces of lead,
which contained all the filver that had been before mixed
with the litharge, becaufe in the lead which had been re-
duced from the litharge in the above manner there were
no perceptible traces of filver. This lead was then melted
over a flow fire, and caft into bars, which were rolled fmooth
and formed into mafies of a known weight, to be ufed for
affaying gold and filver, and for other purpofes of the fame
kind. All thefe meltings were made in one crucible, which,
according to every appearance, remained unhurt. If the
fame experiments were made with red lead, the like refult
would infallibly follow.

The caufe of this procefs, and of the effeéts thence pro-
duced, is, that when lead, which contains a fmall quantity of
filver, is calcined and brought into the {tate of litharge, the
filver in it, if not fcorified, is diffufed in infinitely fine par- —
ticles, fo that it is impoflible for it to fink through the melted
litharge and fettle at the bottom. When the lead calx is
revived on the furface, the leaden grains, as they are formed,
fink down through the litharge, and carry with them the
fcattered grains of filver, in fo far as this leaden fhower, if,
I may fo name it, is compact and powerful enough to col-
le& them. Were the opinion of thofe juft, who affert that
a calx of lead free from filver, when revived by tartar, ac-
quires again, by the creation of new filver, a portion of that
metal, litharge ought not to be revived by tartar, or any
thing of the like kind from the vegetable,kingdom; but on
this occafion I found no fuch effeét produced.

Second Experiment.

With the fame view of obtaining lead free from filver, I
melted, in the like manner, half a pound of white lead,
‘which produced half an ounce of lead. When the litharge
flanding over it was revived, the lead obtained was ftill

| found

Method to purify Lead. for Affaying. 15
found to contain too much filver. I therefore precipitated
another half pound of white lead by charcoal powder, after
the lead that fell from it had been feparated; and then it

produced, by reviving, a mafs of lead without any mixture
of filver.

Third Experiment.

Cupels, employed for refining filver, imbibe about the
half of their weight of lead calx. One might therefore be-
lieve, that when this’ lead calx is revived it would produce
lead free from filver. Befides the obfervation of others,
which confirms the contrary, I have made experiments with
the afhes of fuch cupels in which affaying had been per-
formed with the utmoft accuracy; but I found that the lead
thence made into ingots contained fometimes more than one

“quarter of a grain of filver in the pound. The bone athes,
from which cupels are generally caft, are, by themfelves,
almoft infufible; and this, on account of the great number of
fluxes which muft be employed to bring them to a fluid tate,
makes the fufion of them difficult and expenfive. To four
parts of fine pounded cupel afhes, I put four parts of
potath, four parts of falt, three parts of tartar, and one part
of clay, which mixed together produced, after being melted,
I; part of lead, making almoft 44 parts in the hundred *,
But this ftill contained the above-mentioned quantity of
filver, and could not therefore be proper for the propofed
end.

As the two firft-mentioned experiments will completely
anfwer the purpofe, it is perhaps unneceflary to feek for
other methods ; as it will be hardly poffible to find any lefs
complex, or cafier to be put in practice.

* There muft here be an error in the original., Inftead of s2 part of
lead, we ought, perhaps, to read 13

ap. ; IV.. On

[os26 Ts

YV. On the Inv iesine ty int the Rate of Going of fine piecit
occafioned by the Influence of Magnet ifm. An original Com=
munication, by Mr. VARLEY.

Havine ftudied the theory of clock and watch-making
many years, as well as been, part of that time, concerned
in an extenfive manufactory of watches, I have had many
opportunities of obferving a circumftance which has fur-
prifed every one in the trade as well as myfelf; that watches
of confiderable price, and from the hands of excellent work+
men, often perform no better than a plain one of inferiot
workmanfhip and much lower price. Being anxtous, as may
naturally be fuppofed, to furnifh my friends with watehes or
clocks which would go well, I made it my bufinefs to pay
particular attention to whatever could contribute to their
perfection. With this view, I made almoft numberlefs ex-
periments and obfervations on the various efcapements now
in ufe, the different conftructions of balances, peridulums,
pendulum fprings and compenfations, both for clocks and
watches, which have been applied by very ingenious me-
chanics and excellent workmen to corre& the errors in the
rate of going, efpecially ef watches, occafioned by the va-
rious degrees of heat and cold, change of pofition, external
agitation, influence of oil, friction, variation of maintaining
power, and other caufes.

Some of thefe contrivances are extremely well adapted to
anfwer the intended purpofe} but, notwithftanding all their
advantages, the maker and purchafer are frequently difap-
pointed in the performance of the machine to which they
are applied. Many initances might be produced where tHe
beft workmen have been esaan ed, no expencé fpared by
the maker, and the above-mentioned improvements applied
with the utmoft care and attention; and yet the rate of
going of the watch has been move irregular than in fome
ordinary watches. When fuch a circumftance occurs, it is
extremely unpleafant: the purchafer not underftanding the

difficulties

bya of Magnetifin on Time-pices. 17
difficulties which the maker has to encounter, thinks himfelf
ill ufed, and the Jatter fuffers at the fame time in his repu-
tation as an artift; and 1m his character as a-man; and when
the watches happen to have been made for nautical purpofes,
or for exportation, the whole community; in fome meafure,
become fufferers.

The intention of the prefent paper is to point out a defect.
in the conftruction of time-pieces of every defcription in
which balances are ufed, and at the fame time a fource of
error in their performance, which has been hitherto little
if at all fufpected, but which, where it occurs, completely
defeats all the ends intended to be anfwered by the applica
tion of the above-mentioned ingenious contrivances: and
that it does occur very frequently, will be made fufficiently
obvious bya fimple detail of facts fupported by aétual ex-
periments. .

That the balances of watches; whtn mianufa@tured of
fteel, as they moftly are, might be in a {mall degree magnetic;
and confequently have fome influence in difturbing their
vibrations; has been fufpected by fome and denied by others:
but that a circular body, fueh as a balance is, fhould poffefs
polarity ; that a particular point.in it fhould have fo ftrong
a tendency to the riorth; and an oppofite point an equal
tendency to the fouth, as to be fufficient materially to alter
the rate of going of the machine when put in different
pofitions; has never, I believe, been even fufpected: If it
shad, the ufe of fteel balances would have been laid afide long
ago, particularly where accurate performance was indifpen-
fible, as in :time-pieces for aftronomical and nautical purpofes.
Though [have frequently exainined, with great cate, watches
that did not perform well; even when no defect in their
conftruétion or finifhing was apparent, ahd fufpected the
balance to be magnetic, yet I never could have imagined
that this influence, opetating as a caufe, could produce fo
great an effect as I found upon actual experiment; for I
did not expect to find that a balance, eyen when magnetic,
ncVot. I, . © fhould

-
:

3 Ejeet of Magnetifn on Time-pieces.
{hould have diftin@ poles.’ Happening to have a watch inf
my poffeffion, of excellent workmanfhip, but which per-
formed the moft irregularly of any watch I had ever feen,
and having repeatedly examined every part with particular

attention, without bemg able to difcover any caufe likely”

to produce fuch an effect, it put me upon examining whe-
ther the balance might not be magnetic’ enough to kirk
the irregularity obferved in ffs rate Hof going.

T took the balance out of its fituation’ in the watch, and,
after removing the pendulunr fpring, put it mto a poifing,
tool, intending to approach it with a magnet, but at a con-
fiderable diftance; to obferve the effeét, while at the fame
time the diftance of the magnet flould preclude the poffibi-
lity of the magnetic virtue being thereby communicated to
the balance. Thad no fooner put tt into the tool than F
obferved it much out of poife; that is, the one fide appeared
to be heavier than’ the other: but, as it had been before ex-

amined, in that particular, by a very careful workman, more

than once, I was at a lofs to determine what to think of the
effe&t I faw ; when happening to change the pofition of the
tool upon the board, the balance then appeared to be in
poife. As there could be no magic in the cafe, it appeared
that the balance had magnetic polarity, ds‘no other caufe
could produce the effect I had witneffed, and which was
repeated as often as I ehofe to move the tool from the one
pofition to the other. It happened: that I was then fitting
with my face to the fouth: acireumftance that led me, in
placing the plane of the balance vertically, to put it north
and fouth, and of courfe the axis eaft amd weft—the only

pofition in which the magnetic influence could make itfelf

moft apparent, and which will account for the circumftande
not having been obferved by the workman who examined.
the poife of the balance before I did; for, as oftem as E
placed the plane of the balance vertically between eaft and
weft it was in poife, whichever end of its axis was placed
towards the fouth, .

Hating

Efeet of Magnetifm on Time-pieces. 1g

Having pretty well fatisfied myfelf as to the caufe, I now
proceeded to determine the poles of the balance. With that
view I placed its axis in a vertical fituation, and of courfe its -
plane was horizontal; and I was much furprifed to find that,
in that pofition, it poffeffed fufficient polarity to overcome
the friction upon its pivot; for it readily turned on its axis
to place its north pole towards the north. Making a mark
on that fide that I might know its north pole, I then re-
peatedly turned that point towards the fouth; and, when left
at liberty, it as often refumed its former pofition, performing
a few vibrations before it quite fetiled itfelf in its fituation
and came to reft—exactly as a needle would do if fufpended
in the famie manner.

I was extremely happy that I had obferved thefe effets
before I brought a magnet to make the experiment I firft in-
tended, asI might, and as others alfo might have concluded,
that the polarity had been produced by the approach of the
magnet. I now, however, brought a magnet into the fhop,
and, prefenting its fouth pole to the marked fide, that is, to
the north pole of the balance; the balance continued at reft ;
but upon prefenting the north pole to the marked place, it
. immediately receded from the magnet, and refumed its for-
mer pofition whenever the magnet was withdrawn.

No doubt now remaining as to the faéts, and being in
poffeffion of the pofition of its poles, I proceeded to examine
the effects produced by this caufe upon the watch’s rate of
going; Having put on the pendulum fpring, and replaced
the balance in the watch, I laid the watch with the dial
upwards, that is, with the plane of the balance horizontally,
and in fuch a pofition that the balance when at its place of reff
‘ fhould have its marked fide toward the north :—in this fitua-
tion it gained 5/ 35” in twenty-four hours. I then changed
its pofition fo that the marked fide of the balance when at reft
fhould be towards the fouth, and, obferving its rate of going
for the next twenty-four hours, found it had loft 6’ 48”—
producing, by its change of pofition only, a difference of

C2 12!

40 Effect of Magnetifm on Time-pieces.

12/ 23” in its rate. It muft be obvious to every perfon, tha’
even this difference, great as it was, would be increafed or
ditninithed as the wearer fhould happen to carry in his
waiftcoat pocket a key, a knife, or other article made of
fteel. This circumftance, taken along with the amount of
the vatiation occafioned by the polarity of the balance, was
fully fufficient to produce all the irregularity obferved in the
going of the watch.

I then took away the fteel balance, fubftituted one made
of gold, and, having brought the watch to time, obferved its
rate of going, and found it as uniform as any watch of the
like conftruction; for, though it was a duplex efcapement,
which is perhaps the beft yet invented, at leaft for common
purpofes, it had no compenfation for the expanfion and egn-
traGtion occafioned by heat and cold, and therefore a perfect
performance was not expected.

Steel balances beg commonly in ufe, and, on that ac-
count, eafieft to be Bahn and being on many accounts
preferable to any other, I was unwilling to abandon them
entirely; but refolved to take the precaution of always trying
them before I fhould apply them to ufe. The mode I adopted
was, to lay them upon a flice of cork fufficient to make them
float upon water, and I was in hopes that out of a confider-
able number I might be able to feleét fufficient for my pur-
pofe; but to my furprife, out of many dozens which I tried
in this manner, I could not fele& one that had not polarity.
Some of them had it but in a weak degree, and not more than
one or tivo, out of the whole quantity, appeared to have it
fo flrong as the one which gave birth to thefe experiments
and to the prefent paper, which is perhaps more prolix than
could be wifhed: but the fubje& appeared to be not unin-
ierefting, and I hope the remarks I have offered will not be
altogether ufelefs, as every thing that can tend to add to the
perfection of time-pieces, or to remoye any caufe that operates
againit their perfection, is of fome importance.

My only motive in fending this for publication in the

Philo-

Efe of Mapnetijm on Time-pieces. at
Philofophical Magazine is to render fome fervice to a feience
which I at firft ftudied for amufement only, having never
been inftruéted in any part of it, and for fome years without
the moft diftant idea of ever following it as a bufinefs.
Should it prove acceptable, I may perhaps follow it up with
a demonftration, and a few diagrams to illuftrate the fore-
going experiments, and to caft fome light on other branches
of this feience; particularly on the various efeapements now
in ufe, and the advantages and difadvantages of their different
conftructions and applications in clock and watch work, In
doing this a compenfation for pendulums will be pointed out,
fimple and cheap in its conftruction, yet calculated to obviate
the inconveniences attending the ingenious but expenfive
contrivances that have hitherto been reforted to, and at the
fame time capable of the niceft adjuftment poffible. This
improvement, for fuch I confider it, will ferve at the fame
time to fhew how our very amufements, and the ftudy of our
leifure hours, when directed to ufeful obje&s, though with
(lender abilities and under many difadvantages, may eventu-
ally be of fervice to our friends in particular, and beneficial
to fociety in general.

Hatton-houfe, S. VARLEY.
May 31, 1798,

P.S. As I am perfuaded a Journal carried’ on upon the
plan you have propofed cannot fail to be ufeful to the com-
munity, and as even hints may fometimes pave the way to
greater improvements, I fhall look over my memorandums,
from among which I may perhaps be able to furnifh you
with Hts on a variety of fubjeéts, for the amufement of
your {cientific readers,

c 3 V, Method

[ 22 j

VY. Method of preparing a cheap Subjlitute for Oil Pains, de
durable as that prepared with Oil, and free from any,
bad Smell. By M. Lupicxe. From the Bibliotheque

. Phyfico-eéconomique, 1792.

Ir often happens that people do not choofe, er cannot
employ oil-painting in the country, either becaufe it doeg
not dry foon enough and has an infupportable fmell, or be-
caufe it is too dear. M. Ludicke employed, with the greateft
fuccefs, the following method for painting rue gates,
doors, and even furniture.

The Proce/s.

Take frefh curds, and bruife the lumps on a ‘waitin:
ftone or in an earthen pan or mortar with a fpatula. After
this operation, put them in a pot'with an equal quantity of
lime well quenched and become thick enough to be kneaded;
ftir this mixture well, without adding water, and you will
foon obtain a white-coloured fluid, which may be applied
with as much facility as varnifh, and which dries very
{fpeedily. But it muft-be employed the fame day, as it will
become too thick the day following.

Ochre, Armenian bole, and all colours which hold with
lime, may be mixed with it, according to the colour which
you with to give to the wood; but care muft be taken that
the addition of colour made to the firft mixture of curds and
lime may contain very little water, elfe the painting will be
lefs durable,

‘Wheri'two coats of this paint have been laid on, it may be
polifhed ‘with a piece of woollen cloth or other proper fub-
ftance, and it will become as bright as varnifh. It is certain
that no kind of painting can be fo cheap: but it poffeffes,
befides, other advantages: in the fame day two coats may.
be laid on and polifhed, as it dries fpeedily and has no fmell,
If it be required to give it more durability, in places expofed

@

On Encauftic Paintings 23,
to moifture, do over the painting, after it has, been polifhed,
with the white of an egg: this procefs will render it as
durable as the beft oil painting.

V1. On the Antiquity and Advantages of Encauftic Painting,
with an Examination of the Procefs employed in that Art by
the Ancients, From a Treatife entitled Antichita, Vantager
¢ Metodo della Pittura Encaufta; Memoria del Ch. Sig.

_ Giov. Fabbroni, &c. Roma, 1797. Quarto.

Tray is much indebted to the penetration of the learned
Abbé Requeno for again bringing forward to the notice of
modern painters wax-painting, (pittura encaufla,) which
was forgotten, and confidered as entirely loft.
_ The ftimulus of curiofity always keeps alive and vigilant
that laudable ambition to which we owe the moft valuable
dlifcoyeries; and writers are ever ready to catch the new idea,
¢ither to appropriate it to themfelves, or at leaft to partici-
pate in the honour of it. .By the collifion of their various
attacks on each other, truth is thruft ferwards fo as to be
more diftin@ly feen than before, and the difcovery thus
acquires more value, and can be sreepioaese more ad- -
vantage. ray
No fooner had Deal, whofe. merit entitles bias to fe
much praife, made known the refult:of his refearches, than
a numerous body appeared.to examine the adyantages of it,
or to fhare in the approbation beftowed on it.’ Some ex-~
plained the claflics in a manner different from what he had
done, and ethers propofed methods which they confidered as
fuperior. Wax, in all probability, forms the only ground of
encauftic painting. .Requeno, from his own ideas, adds
maftic; but-Lorgna converts no lefs*abfolutely his wax into
foap; as Bachelier does with the alkali of foda. The inge-
nigus Aftori, difpleafed with both their readings, withes no
C4 leds

a4 On Encauftic Painting.

lefs abfolutely to add gum and honey, as he affirms that it
would render the wax far more yielding, and much fofter for
the brufh. :

I contented myfelf with confidering, in my clofet, the re-
fult of the laudable difpute of thefe able and meritorious
writers, and thought I could clearly perceive that none of
them had come near enough to the mark, though each of
them had done effential fervice to the art. |

Some of the ancient writers who have thrown light on
this fubje&t, among whom are Varro, Vitruvius, and Pliny,
exprefsly afcribe to the ancient painters the ufe of Punic,
that is Carthaginian, wax. It was faid to be the beft, as it
exceeded in whitenefs the Sardinian and Corfican; and the
reafon of this probably lay in its being better purified; for
the Africans, as Pliny tells us, were accuftomed to ufe alkali
in order to render this fubftance whiter, and, in my opinion,
io free it from all greafy matter. It was then called Punic
wax, as Venetian turpentine, foap, and wax, are now pre-
{cribed in books of receipts in order to fignify the beft; and
we muft conclude, if, inftead of confidering the wax to
have been merely bleached, we convert it into real foap,
arifing from the clofe combination of the wax with the alkali,
that we change and pervert the meaning of thefe authors.
The idea which I formed of the period of encaufti¢ painting,
and the country where invented, was confiderably different,,
and I have had the pleafure of finding it afterwards con:
firmed by experiments and facts.

The knowledge and ufe of encauftic painting is certainly
older than the time of the Greeks and the Romans, to whom
the learned Requeno feems to affign the exclufive poffeffion
of this art; becaufe the Egyptians, who with the Etrufcans
were the parents of the greater part of the inventions known
among mankind, and from whom the Greeks learned fo
much, were acquainted with and employed encauftic paint-
ing in the ancient ages of their greatnefs and fplendour, as is

prove by the valuable fragments of the bandages and

cov erings

On Encauflic Painting. 28
coverings of a mummy painted in this manner, which, by
the favour of our gracious prince, the noble patron and pro-
moter of the arts and feiences, is expofed to the view of
every connciffeur, in his elegant mufeum. The exiftence of
wax on this Egyptian mummy may be difcovered on a bare
view; but I convinced myfelf by other proofs of a lefs du-
bious nature.

Moft of the mummies, however, preferved in colleétions,
are painted with a fize, which appears to be not unlike that
ufed in paintings with water colours (pittwra a tempera) 5 but
it is certain that the Egyptians differed much in their orna-
ments, and the bandages of the’ mummy above-mentioned
are, on this account, more valuable and more worthy of
notice.

I faw in the Britifh Mufeum a mummy which was entirely
covered with glafly grains; and the colour of fome of
them gave me reafon to conjecture that thefe ancient people
were acquainted with the effects of cobalt in fmalt, which
has however been confidered as anew invention. I faw an-
other mummy at Paris, which had for merly belonged to the
celebrated Count Caylus: among other fingularities it had
fome ornaments of leaf gold upon a meen of chalk and
bolus, which is at prefent employed by the European gilders.
In the Royal Mufeum at Florence there is, befides others,
one with gilding of the like kind and very lively colours, But
T will not here enter inte a panegyric of the Egyptians, who
_ accomplifhed fo great things, and much earlier than the
Greeks or the Romans ; it will be fufficient to have fhewn, as
a point unknown in the hiftory of the arts, that thefe people
practifed encauftic painting, as appears beyond a doubt from
the before-mentioned fragment: but I will confefs that this
would be a barren knowledge if it did not lead us to other
ufeful refearches. I muft obferve, in the firft place, that no
oil-painting, perhaps of only two or three hundred years old,
exhibits a white paint that has. kept fo well as that feen on
the above fragment ; and this circumftance fufficiently proves

the

.
26 On Encauftic Painting.
the valuable advantage that method has over the commoty
oil-painting, which, notwithftanding the general opinion,
cannot haye beeri unknown to the ancients ; for, befides olive+
oil, they were acquainted with that of fefamum, turpentine,
cedar, and nut oils. It is impoffible that in Egypt and Phee-
nicia, where fo much ufe was made of flax, the oil pro-
cured in abundance from that plant fhould have been un-
known, Thofe who have kept oil, or who have. fpilt any
of it, whether nut or lintfeed oil, mutt have remarked that
it poffefies the property of foon drying by the effects of the
atmofphere; and therefore it may he eafily believed that
mankind muft foon have, conceived the idea of employing
it, particularly for fhips, which, as Herodotus fays, were
painted with red ochre in the earlieft periods, and adorned
with figures and ornaments. The ufe of oil afforded paint-
ing a much fimpler and eafier method than that of wax ; it
- puft, therefore have been firft adopted, and the tranfition
from oil to wax muft be confidered as a ftep towards /bring-
ing the art to perfection; becaufe encauftic painting is not
expofed to the irremediable inconvéhiencies that arife in oil-
painting, the value of which we extolled through ignorance,
and praifed as a new invention.

Oil in general, and in particular drying of which the
painters -ufe, has naturally a {trong inclination to combines
itfelf with the vital air or oxygen of the atmofphere, and by
imbibing oxygen it becomes dry, and aflumes the character
of refin; but the colour then becomes darker, as is the cafe
with tranfparent turpentine, which gradually becomes a black

itch, ;
. According to the new and more accurate method of de«
compofing bodies, oil confifts principally of hydrogen and
earbon. By coming inte contact with the atmofphere, and
abforbing its oxygen and light, it undergocs a flow and im-
perceptible combuftion, which is not effentially different
from. the fpeedy and violent which it would undergo in the
common mode of burning. It firft pafles, by imbibing oxy-

gen,

Ou Encauftic Painting. 2y
gen, into. the fate of a more or lefs dark refin; lofes gra-
dually its effential hydrogen, which makes a new combina-
tion, and afterwards the oxygen itfelf which has attracted
the carbon; and at length leayes behind a thin layer of ac~
tual carbon, which in the end becomes black in the courfe
of time, and confiderably gbfeures the oil-painting. By a
continuance of the before-mentioned flow combuftion the
carbon itfelf, as it were, burns alfo: if it be ftrongly aéted
upon by-the light, it attracts the oxygen of the atmofphere,
and again brings forward the carbonic acid or fixed air, which
gradually flies off. By this, which I may call the fecond
degree of combuftion, the painting muft become dufly and
friable, like crayon painting (il paftello); a phenomenon
which may be clearly perceived on oil-paintings, which are
generally covered with wood and iron-work, that they may

the better withftand the atmofphere.

The afhes, oxydes, or calces of metals, which are ‘often
ufed as paints, are nothing elfe than metals actually brought
to a burnt or faline ftate by different dofes of oxygen. When
the oil, during the time of the before-mentioned combutftion,
deprives them of fome part of their oxygen by means of its
well-known affinity, the metal again proportionably affumes

. its natural ftate and colour; and as the calces or afhes of
the iron,’ and particularly white lead, return to their former
metallic character, they become, in various ways, black,
by the lofs of the axygen, which, as is well known, is drawn

- from them merely by the contact of the light, efpecially
when ftrong, '

_ Itappears from the preceding theoretical obfervations, that
ene can hope only for a tranfient or deceitful effect from the
yefrefhing of oil-paintings) with oil, becaufe the harmony of
the tones, which the painter eftabiithes as fuited for the mo
ment, docs not proceed with equal fteps, and cannot preferve;

-itfelf in the like meafure for the courfe of a few years, as each
tint, as they fay, ought to increafe, or, to fpeak more properly,
to burn in proportion to its antiquity. Jt thence follows, that

mere

48 On Encauflic Painting.

mere wafhing may be prejudicial to an old painting ; and that
the method of refrefhing paintings, as it is called, by daub-
ing over the furface from time to time with new drying oil, is
highly prejudicial and ill calculated for the intended purpofe,
fince the oil when it becomes dry contraéts in its whole fur-
face, carries with it the paint under it, and occafions cracks
in the painting. New cil of this kind gives oecafion'to mi-
neral paints to be reftored; but covers the picture with a
new coat of refin, and then of carbon, which arifes from the
gradual combuftion, and always caufes more blacknefs, and
the decay of the painting which one wifhes to preferve.
Wax, on the other hand, undergoes a change which Is very
different from that of drying oil. The wax, inftead of be-
coming black by the contaét of the atmofphere, increafes in
whitenefs, and, according to its natural quality, isnot decom-
pofed in the air, and it does not firongly attract the oxygen
of the calces or metallic afhes which are commonly ufed in
painting. Moreover, the fo called earths, which are in them-
felyes white, and are never variable either by the prefence or
abfence of oxygen, cannot be employed in oil-painting, be-
caufe that fluid makes them almoft tranfparent, and caufes
them to remain as it were without body (corpo), and not to
produce the withed-for effeét, That beautiful white, which
may be obferved on the before-mentioned Egyptian encauf~
tic, is nothing elfe than a fimple earth, and according to
my chemical experiments a chalk (creta,) which is alfo un-
alterable. If we confider this encauftic fragment as belong-
ing to the epoch of the firft violent change which the reli-
gious fyftem of the Egyptians experienced, it will be a fpeci-
men of painting of about 2500 years-old; for fuch is the
number of the years that have elapfed fince Cambyfes over-
turned the ceremonies and religious worfhip of the Egyp-
tians, not only by the fword, but by the {till more powerful
weapons of ridicule. Dead bodies were embalmed there in
the time of Herodotus; but the cloth in which they were
wrapped, or the bandages bound round them, were no longer
salts painted

On Extcauffic Painting. 29

painted with facred chara&ters. The bodies were only in-
clofed in wooden cafes, which were more oF lefs ornamented.
Many are of opinion, that an expreffion of the bifhop of Hippo
pives reafon to affert that the people in Egypt continued to
repare mummies even till the fifth century ; but it muft be
obferved that the Egyptians then had adopted the Chriftian
religion ; that they no longer ufed hicroglyphical inferip-
tions, which in the time of Apuleius were faid to be unin-
telligible and forgotten; and that it was not mummies which
were prepared then, but gabbara, as St. Auguftine fays in
his Orations, that is, dead bodies dried after the manner
of mummies, If Bochart and Menage be not miftaken,
the name mummia is derived from maim, which fignifies
wax: and one might therefore believe that the drefs of
embalmed bodies was thus named becaufe wax was cm-
ployed for painting it; and thence it would follow, that
the fragment in queftion may be claffed among the oldett.

Mummies, fince the earlieft periods of the Egyptian cere-
monies, were expofed to a variety of fituations 5 for on cer-
tain occafions they were taken up from the fubterranean
-repofitories in which they were depofited, and placed in the
highways, or at the doors of the houfes, On other occafions
they were carried into the halls where entertainments were
celebrated, and they were alfo given as pledges of fidelity
in various tranfactions.

After the fall of Egyptian ‘grandeur, the mummies were
left buried and negleéted in dark vaults, amidft a damp foil,
from which they were “drawn forth only at a late period,
_ by European curiofity, in order to ornament collections, or
"by the avarice of the Mahometans, who hoped to make them
an article of gain.

Many have remarked, and in particular Maillet during
bis confulfhip at Cairo, that the Arabs, when they find mum-
mies of good appearance, ufually cut them to pieces, in order
to examine whether any thing of value is concealed in their

clothing.

30 On Encauflic Painting.
clothing. Ican affign no other caufe for the fragment itt
queftion ; and this would enhance the value of it, and render
more important, as well as more ufeful, its great antiquity,
and the beautiful painting to be feen on it.

Tn all probability the ancients, as I have already faid, were
once acquainted with the ufe of oil-painting, and loft or
neglected it afterwards, fo thai it was perhaps employed only

fometimes by a few.

Petronius praifes the frefh appearance which the valuable
works of Zeuxis and Apelles had, even in his titne ; but
Cicero, on the other hand, {peaks of the paintings of the
ancients having fuffered from blacknefs. The former fpeaks
of wax-painting, and the latter certainly alludes to paintings
in oil. It is well known that paintings with wet chalks or
water colours do not become black by age, and that this is
the cafe alfo with encauftic. Of this any one may be
convinced, not only by the expreffions of the above quoted
authors, but by one’s own eyes on furveying the Egyptian
fragment alluded to, Galland proves, on various grounds,
that a painting was made with oil fo early as the reign of
Marcus Aurelius; and if no fpecimens of that period have
reached us, this is perhaps to be afcribed to the frail and
perifhable nature of this fpecies of painting.

The oldeft oil-painting now in exiftence,. as far as I knowy.
is a Madonna and child on her arm with an eaftern counte-
nance. It has marked on it the date, which is thus exprefled
acecrxxxvJ. If we exprefs thefe with Krabic charaéters,~
it would make, in my opinion, 886, and the period of this
piece would fall about the time of Bafilius or Charlemagne.
This fingular and valuable painting, found in the old palace
(palazzo vecchio) of the Florentine republic, is preferved at
prefent in the chapel of the noble and Icarned diretor Ben=
civenni otherwife Pelli, who purchafed it of a broker in the
fireet for a few livres. I muft however remark, that if
inftead.of the above date we ought te read MCOCLXXXVI,’

which

Method of Proving Wine: gt
‘which appeats to me probable, it would ftill be one of the
oldeft of its kind in Italy, and belong to the oil-paintings of
the fourteenth century, feme of which are mentioned by
Dominici and Tirabofchi prior to the difcovery of the cele-
brated Van Eye.

(To be concluded in the next Number.)

VIL. Mothod of difcovering whether Wine bas been adulterated
with any Metals prejudicial to the Health. By M. Hanue-+
‘MANN. From Bibliotheque Phyfico-économiqiue.

‘Tue property which liver of fulphur (alkaline fulphures)
and hepatic air (fulphurated hydrogen) poffefs of precipita-
tung lead ina black form, has been long ago made public;
and this property has been employed to determine the qua-
lity of wines by means of the liquor probatorius Wirtem=
bergenfis, or Wirtemberg proving liquor.

But, in trying wines fuppofed to have been adulterated, this
proof does more hurt than fervice, becaufe it precipitates iron,

‘of the fame colour as the pernicious lead. Many wine-mer-
chants therefore of the greateft refpeStability, rendered by
thefe means fufpected, have been ruined.

There was wanting then a re-agent, which fhould difcover

in wine thofe metals only which are prejudicial to the health
of man.
_ The following liquor precipitates lead and coppe? in a
black form, and arfenic of an orange colour, &c. but does.
Not precipitate iron. The lat, which is not noxious, and
rather falutary to the conftitution, Tea gets into wines
by accident.

vit began Method Of ‘preparing the Proving ae
“Mix ‘equal’ parts of oyfter fhells and crude fulphur in’ a
§ne powder, “arid put the mixture into a crucible, Heat it

32 Ox the Solar and Lunar Period of 600 Years.

in a wind furnace, and increafe the fire fuddenly, fo as td
bring the crucible to a white heat, for the fpace of fifteerr
minutes. Pulverife the mafs when it is coo}, and preferve it
in a bottle clofely ftopped:

To prepare the liquor, put 120 grains of this powder and
120 grains of cream of tartar (acidulous tartarite of pot
aff) intoa ftrong bottle; fill the bottle with common water,
which boil for an hour, and then let it cool ; clofe the botthe
immediately, and fhake it for fome time: after it has re-
mained at reft to fettle, decant the pure liquor, and pour it
into fmall phials capable of holding about an owhce each,
fir putting into each of them 20 drops of muriatic acid.
They muft be {topped very clofely with a piece of wax, in
which there is a {mall mixture of turpentine.

One part of this liquor mixed with three’ parts of fufs
pected wine, will difcover, by a very fenfible black precipi-
tate, the leait traces of lead, copper, &c. but will produce
no effect upon iron, if it contains any of that metal. When
the, precipitate has fallen down, it may ftill be difcovered
whether the wine contains iron, by faturating the decanted
liquor.with a little falt of tartar (tartarcous acidulum. of
potafh); by which the liquor will immediately become black.

Pure wines remain clear and bright after this liquor has
been added to them,

VIII. On the Solar and Lunar Period of Six Hundred Years:
__ By Profeffor Burya, Member of the Royal Academy of
“Sciences at Berlin. Ext wtih, from a Fie rag on thé

“. 131 of December 1492.

_ HE hiftoriart Jofephus' fays that Ged prolonged the
lives of the patriarchs to at leaft fix hundred years, that they
might, become more perfec in the knowledge of aftronomy;

becaufe

On the Solar and Lunar Period of 600 Years. 33

s becaufe the great year is always completed at the end of
aac period.

No other ancient writer, however, makes any mention of

-this great year; but Pliny in his Natural Hiftory relates,
that Hipparchus had fixed the courfe of the fun and moon
at fix hundred years; which feems to refer to a period of
that duration: and it is to be conjectured, that it was efta-
blithed by the ancients in order td compare the courfe of the
moon with that of the fun, and to foretel for a confiderable
time beforehand the phafes of the moon.
_ This, indeed, was one of the principal objects of the
ancient aftronomy. Méeto invented the period of nineteen
years, becaufe he believed that nineteen tropical folar years
made exa€tly 235 lunar months. Calippus quadrupled this
period, and made a new one of 76 years. Hipparchus qua-
drupled thefe 76 years, and by thefe means obtained a more
accurate period of 304 years.

Now it may te readily fuppofed, that Hipparchus, in the
hopes of deviating ftill lefs from the truth, at length doubled
his period, and brought it to 608 years; for, otherwife, why
fhould he have fixed his period even at 609 years ?

According to every conje€ture, the great year is nothing
elfe than the laft doubled period of Hipparchus ; for, though
Pliny and his cotemporary Jofephus fpeak in round num-
bers of 600 years, or fix centuries, yet we know that ma-
thematical accuracy is not always obferved in the language
of common life and of hiftorians.

Mr. Bailly explains the period of fix hundred years ina
manner totally different. That aftronomer finds, like all
thofe converfant with the fubje€t, that 600 folar years form
no whole number of lunar months without a fraétion: but
as that would be the cafe if the year were affuined a little
longer, as it really is, he thence concludes that the year in
ancient times was actually fo long as the precifion of the
period of 600 years requires; and befides, that thofe ages

Vou. I. D produced

340 On the Irritability of Sea Sponges.

produced very able and expert aftronomers, who difcovered

this period by an aftonifhingly long feries of cbfervationsy

In this manner every period, however aflumed at pleafure,
might be juftified. It would be only neceflary to reckon
what length of year it would require ; to aflume a certain
acceleration in the revolution of the earth; to determine
thereby at what time the year had the requifite length 5

and then to be aftonifhed how accurate mankind were in -

their aftronomical calculations at that period.

The reader may determine between both thefe explana-
tions. It might ftill be fuppofed, that the ancients really
had a period of exaétly 600 years, neither more nor lefs, and
that they deduced it from a falfe determination of the length
of the year. But this would not agree well with the reft
of their known periods.

1X. On the Irritability of Sea Sponges. From Neue Nordifche
Beytrige, Dy Profefor PALLAS.

if HAVE for a long time remarked in different kinds of
fponge (/pongie ), particularly the /pongia villofa, and alk
tough fea fponges, and even the commonett fponge em-
ployed in bathing-houfes, when not too much ufed, certain
remains.of irritability, which, in thefe bodies kept fo long
out of their own element, cannot be confidered but as me-
chanical. If the above fponges be foaked in cold water
until they extend to their full magnitude, and hot water be
poured over a part, or the whole of them, they inftantane-
oufly contra& themfelves, particularly in the irritated part,
with a wonderful velocity and force, as if alive. As foon,
however, as the irritation of the heat ceafes, they again ex-
tend to their former fize. ‘This experiment may be repeated
with a f{ponge, until its whole confiftence and texture are
deftroyed by the hot water. An accidental obfervation made,

on

a

Theory of Cryftallization. 20
#n a tubular piece of the before-mentioned /pongia villofa
firft induced me to repeat the fame experiment on other _
kinds of tough fea fponges.

X. On the Theory of the Structure of Cryftals.
[With a Plate, No. U.]

\ \ HEN we refleét on the rapid progrefs which has been
of late made in moft branches of natural knowledge, and
particularly in chemiftry and mineralogy, and confider how
much thefe may be facilitated by a competent knowledge of
thofe regular forms which all mineral and faline fub{ftances
affume, in certain circumftances ; it appears furprifing, that,
though we have a number of books which treat on chemif-
try, we have not one Englifh work on the theory of the
ftru€ture of cryftals. To remedy this defect in fome de-
gree, and as an introduction to original papers on the fub-,
ject promifed to us by an eminent mineralogift, we think
proper to lay before our readers the following tranflation of

The Abbé Ha urs Theory of Cryfallization. From
Vol. XVII. of the Annales de Chimie.

T GAVE in this Journal, fome years ago, a fhort account
of the theory of cryftallization ; but that paper may be
confidered only as a fhort fketch, and more calculated for
thofe who with not to be entirely ignorant of the fubjed,
than for thofe defirous of becoming thoroughly acquainted
with its principles and refults. In the prefent paper I pro-
pofe to afford the latter an opportunity of obtaining their
object, by prefenting them with the theory required, and
with all the facts necéflary to give them a juft idea of the
laws to which it is fubjeét, and of the progrefs by which it
has been carried to {uch a degre¢ of generalityy that an im-

D2 menf{e

36 Theory of Cryftallization.

menfe number of facts, formerly unconnected, now become
arranged, as if of themfelves,- around a fingle one on which
they depend, and which ferves to connect them all by mutual
relations.

I confefs, however, that this theory can be well underftood
only by the help of analytical calculations*. Befides the
advantage which analyfis has of involving in the fame for-
mula the folutions of an infinite number of different pro-
blems, it alone can give to the theory the character of abfo-

Jute certainty, by producing refults, perfectly agreeable to

thofe we receive from obfervation.

Notwithftanding thefe confiderations, 1 thought it would
be better for thofe unacquainted with the fcience of calcu-
lation, if I adhered to fimple reafoning, accompanied by
geometrical figures, which are fo ufeful in aflifting the ima-
gination to conceive the arrangement of thofe fmail folids
that concur to form acryftal, but which were wanting to
the firft paper. -

This arrangement I call /irudure, as oppofed to the term
erganization, which exprefles the far more compound me-
chanifm of animals and plants.

If this procedure be lefs direct, lefs expeditious, and lef
precife; and if it requires us to attend to thofe details
which algebra pafles over in order to conduét us fpeedily
to its object, it is at leaft attended with this advantage,
that the mind by its means perceives better the connexion of
the different parts of the whole undez its confideration.

I. Mechanical Divifion of Cryfrals.

It is known that the fame mineral fubftance is fufceptible
of many different forms well defined, fome of which do not
prefent, on the firft view, any common point of refemblance
that feems to indicate their relation. If we compare, for
example, calcareous {par in a regular hexaedral prifin with

Ba: ‘S@ Memoiies de l’Acad. des Sciences, An 1790. .
the

Theory of Cryftallization. 37
the rhomboid * of the fame {par whofe large angle is about
1012.°, we fhall, at firft, be inclined to believe that each of
thefe two forms is entirely foreign to the other. But that
point of union which efcapes our notice, when we confine
ourfelves to the confideration of the exterior form, becomes
fenfible when we penetrate into the internal mechanifm of
the ftructure. Let me here then be permitted to trace
things from their origin, by relating how the obfervation
from which I fet out, and which has become the key of the
whole theory, firft prefented itfelf to my mind.

I was holding in my hand a hexaedral prifm of calcareous
{par, fimilar to the one I have mentioned, and which had
fallen from a group of which it formed a part. The frac-
ture prefented a very fmooth furface, fituated obliquely, like
the trapezium p fu ¢ (fig. 1), and which made an angle of
135°, both with the refidue 2 bc /p 4 of the bafe, and with
the remainder tue fof the planeine f Obferving that
the cuneiform fegment p fu tin feparated by this fracture
from the cryftal had for vertex one of the edges of the bafe,
that is to fay the edge i , 1 wifhed to know if I could detach
a fecond fegment in the part to which the next edge ¢ 7 be-
longed, by employing for that purpofe the blade of a knife

* T give the name of rhomboid to a parallelopipedon ae (fig. 4) termi-
nated by fix rhombufes equal and fimilar. In every rhomboid two of
the folid angles fuch as a, ¢, oppofite to each other, are formed by the junc-
_ tion of three equal plane angles. Each of the other fix folid angles is
formed by a plane angle equal to each of the preceding, and by two other
angles of a different meafure, but equal toeach other, The points a,e, are
the fummits, and the line a ¢ the axis. In any one whatever a 4 df of the
rhombufes, which compofe the furface, the angle a, contiguous to the fum-
Mity is called the /uperior angle; the angle d the inferior angle; and the
angles 4 and f are the /ateral angles, The fides aé, af, are the /uperior
edges; and the fides dd, df, thé inferior edges; 5 f is the horizontal dia-
gonal; and a d the oblique diagonal. The rhomboid is obtufe or acute ac-
cording as the angles of the fummits are obtufe or acute. The cube is the
boundary of the rhombvids.

D3 direied

38 Theory of Cryftallization.

dire&ted in the fame degree of obliquity as the trapezium
pfut,and aflifted by the ftrokes of a hammer. This attempt
was fruitlefs; but having tried the fame operation towards
the following edge 4c, 1 uncovered a new trapezium fimilar
to the firft. The fourth edge a 4 refifted the inftrument like
the fecond ; but the next one ah yielded eafily to the me-
chanical divifion, and prefented a third trapezium of as fine
a polith as the other two. It is almoft unneceffary to add,
that the fixth edge i 4 remained indivifible, like the fourth
and the fecond.

I then proceeded to the inferior bafe de fg & r, and obfer-
vation proved to me that the edges of this bafe, which admit-
ted fections like the preceding, were not the edges éf, dr, gh,
correfponding with thofe I had found divifible towards the
upper part, but the intermediate edges de, vy, gf The tra-
pezium /¢y v reprefents the fetion made below the edge ér.
This fe€ion is evidently parallel to that of the trapezium
p/# #, and in the like manner the four other trapeziums are
parallel two totwo. But thefe different fe¢tions being in
the direction of the natural joining of the laminz, I eafily
fucceeded to obtain more fections parallel to each of them,
while it was impoffible to divide the cryftal in any other di-
rection. By continuing this mechanical divifion, determined
by the parallelifm above mentioned, I came to new fections,
always nearer the axis of the prifm ; and when thefe fections
had made the remainders of the two bafes to difappear, the
prifm was transformed into the folid OX (fig. 2) terminated
by twelve pentagons, parallel two to two, of which thofe at
the extremities SAOIR, GIODE, BAODC, on the one fide,
and KNPQF, MNPXU, ZQPXY, on the other, were the
yefults of the mechanical divifion, and had their common
vertices O, P, fituated in the centres of the bafes of the prifm,
(fig. 1). The fix lateral pentagons RSUXY, ZYRIG, &c.
( fig. 2) were the remains of the planes of the fame prifm.
' In proportion as I multiplied the feCtions, always parallel
¢o the preceding, the lateral pentagone decreafed in height 5

and

20

Theory of Cryftallization. 39

and at a certain term the points RG becoming confounded
with the points YZ, the points SR with the points UY, &c.
there remained nothing of the pentagons in queftion but
the triangles YIZ, UXY, &c. (fiz: 3). Beyond that term
the fetions happening to pafs over the furface of thefe tri-'
angles diminifhed gradually their extent, until, at length,
thefe triangles were loft; and then the folid which arofe
from the hexaedral prifm became a rhomboid a e ( fig. 4) en-
tirely like that commonly diftinguifhed under the name of
Icelandic {par.

A refult fo unexpected made me immediately conceive the
idea of fubjecting the other calcareous cryftals to the fame
proof; and all yielded to the mechanical divifion in fuch a
manner, that, when the external faces had difappeared, the

_ kind of nucleus which remained under the inftrument was

ftill a rhomboid of the fame form as the firft. The only
thing neceflary was to find the dire€tion of the feétions
which conduéted to the central rhomboid.

To extract, for example, ‘this rhomboid from that fpar
called commonly the /enticular, and which is a much more
obtufe rhomboid, having its great plane angle equal to
114° 18’ 56”, it was neceflary to begin at the two vertices,
making the fections pafs through the leffer diagonals of the
faces. If it were wifhed, on the contrary, to get at the nue

- cleus of the rhomboidal fpar with acute vertices *, it would

be neceffary to direét the fe€tions of the planes parallel to
the edges adjacent to the vertices, and in fuch a manner
that each of them fhould be equally inclined to the planes

it cuts.

Thefe refults are the more worthy of attention, as it would
at firft feem that cryftallization, after having onee adopted
the rhomboid, in regard to one determined fpecies of mine-
ral, ought always to re-produce it with the fame angles. But

* This rhomboid, as well as the preceding, will be farther explained in
she courfe of the prefent article.

D4 the

Pr en | Theory of Cry/lallications

the paradox arifing from this diverfity of appearance is exe tas

plained by the double ufe of the rhomboidal form, which —

ferves here to difguife itfelf, and which conceals fixed and Ph

conftant charaCterifing marks under a variable outfide.

If we take a cryftal of another nature, fuch as a cube of
fluor fpar, the nucleus will have a different form. This,
in the prefent cafe, will be an oftaedron, to which we hall
arrive by taking off the eight folid angles of the cube. Heavy
{par will produce, for nucleus; a right prifm, with rhomboidal
bates ; feld {par an oblique-angled parallelopipedon, but not
rhomboidal * ; the apatite or beryl a right hexaedral prifm;
the adamantine {par a rhomboid, a little fharpened ; blend
a dodecaedron, with rhomboidal planes; iron of the ifland
of Elba, a cube, &c. and each of thefe forms will be conftant
in regard to the whole {pecies, fo that its angles will undergo
no variation of importance; and if an attempt be made to
divide the cryftal in any other dire€tion, we fhall not be able
to find a joining. Nothing will be obtained but undefined
fragments: in a word, it will be broken rather than divided.

Thefe folids, infcribed, each, in all the folids of the fame
{pecies, ought to be confidered as the real primitive forms
on which all the other forms depend. All minerals, I con-
fefs, are not fufceptible of being divided mechanically, but
there area greater number than I at firft thought ; and with
regard to thofe cryftals which have hitherto refifted my ef-
forts to find their natural joinings, I have remarked that their
furface, ftriated ina certain direction, or the relation of their
different forms among thofe which belong to the fame fub-
ftance, often prefent indications of their ftru€ture ; and that,
reafoning from their analogy with other divifible cryftals,
we may determine that firucture at leaft with great pro-
bability.

I call fecondary forms all thofe that differ from the primi-
tive form. We fhall fee, hereafter, that the number of thefe

= Mem. de l'Acad, des Sciences, An 1784, p. 237

forms

Theory of Cryftallization, 4t
forms has limits, which can be determined by theory, ac-
cording to the laws to which the ftru€ture of cryftals is fub-
jeCted.

The folid of the primitive form, obtained by means of the
operation above explained, may be fubdivided in a direCtion
parallel to its different faces: all the enveloping matter is
equally divifible by feCtions parallel to the faces of the pri-
mitive form. It thence foliows that the parts detached by
the help of all thefe feCtions are fimilar, and differ only in
their bulk, which continues to decreafe ‘in proportion as the
divifion is carried ftill farther. We, however, mutt except
thofe which are near to the faces of the fecondary folid; for,
thefe faces not being parallel to thofe of the primitive form,
the fragments which have one of their facets taken in the
fame faces cannot entirely refemble thofe detached towards
the middle of the cryftal. For example, the fragments of the
hexaedral prifm (fig. 1), the external facets of which make
_ part of the bafes or of the planes, have not, in that refpe@,
the fame figure as thofe fituated nearer the centre, and of
which the facets are all parallel to the fe€lions p/fuz,
1qy vv, &c. But theory, as I fhall fhew, removes all the
embarraflment which, on the firft view, arifes from that
_ diverfity, and reduces the whole to an unity of figure.

But the divifion of the cryftal into {mall fimilar folids has
aterm beyond which we fhould come to particles fo {mall,
that they could no longer be divided without analyfing them;
that is to fay, without deftroying the nature of the fubftance.
I ftop at that term;.and I give to the corpufcula we fhould
infulate, if our organs and inftruments were fufficiently
delicate, the name of integral molecule. It is very probable
that thefe molecule are thofe which were fufpended in the
fluid in which the cryftallization was effected. But my
readers may judge for themfelves. We may, however,
with truth, affert, that, by the affiftance of thefe molecule,
} Prony reduces to fimple laws the different metamorphofes of
cryftals,

42 Theory of Cry fallization.
cryftais, and arrives at refults which exadtly reprefent thofe
of nature ; and this is the only end | propofed.

When the nucleus is a parallelopipedon, that is to fay, a
folid with fix parallel faces, two to two, like the cube, the

rhomboid, &c.. and this folid does not admit of any other -

divifions than thofe made in the direction of the faces, it is

evident that the molecule refulting from fubdivifion, both »

of the nucleus and of the enveloping matter, are fimilar to
the nucleus. In other cafes the form of the moleculz differs
from that of the nucleus. Theresare alfo cryftals which, by
help of the mechanical divifion, yield particles of different
figures, ‘eombined together throughout the whole extent of
thefe eryftals. I fhall explain hereafter my conjectures on
the manner of refolving the difficulty prefented by thefe
kinds of mixed ftructures; and it will be feen that this difl-
eulty does not affect the theory at bottom.

If. Laws of Diminution.

3. Diminution at the edges.

The primitive form and that of the integral moleculs
being determined, after the diffeCtion of the cryftals, it was
neceflary to difcover the laws according to which thefe
molecule were combined to produce, around the primitive
form, thofe {pecies of envelopes, terminated fo. regularly, and

from which refulted polyedra fo different from each other 5

though originally of the fume fubftance. But fuch is the
mechanifm of the ftru€ture fubject to thefe laws, that all the
parts of the fecondary cryftal, fuperadded to the nucleus,
are formed of laminz, decreafing regularly by the fubtra€tion
of one or more ranges of integral molecule; fo that
theory determines the number of thefe ranges, and, by a
meceflary confequence, the exact form of the fecondary
cry ftat.

To give an idea of thefe Iaws, I fhall firft make choice of a
very fimple and very elementary example. Let us conceive

EP

Theory of Cryftallization. 43

EP (jig. 5) to reprefent a dodecaedron, whofe faces are
equal and fimilar rhombufes; and that this dodecaedron is a
fecondary form, which has a cube for its nucleus or primitive
form. The pofition of this cube may be eafily conceived
by infpecting fig. 6, where jit is {een that the {mall diagonals
DC, CG, GF, FD, of the four faces of the dodecaedron,
united around the fame folid angle L, form a fquare, CDFG.
But there are fix folid angles compofed of the four planes,
viz. the angles L, O, £, N, R, P, (fg.5)3 and, confe-
quently, if fections are made to pafs through the fmall diago-
nals of the faces which concur to the formation of thefe
folid angles, we fhall fucceflively uncover fix fquares, which
will be the faces of the primitive cube, and three of which
are reprefented (jig. 6), viz. CDFG, ABCD, BCGH.

This cube would evidently be an affemblage of integral
cubic moleculz, and it would be neceflary that each of the
pyramids, fuch as LDCGF (jig. 6), which reft on the faces,
fhould itfelf be compofed of cubes equal to each other, and
to thofe forming the nucleus.

To make it more apparent how this might take place, I
fhall point out the means of making an artificial dodecaedron,
by employing a certain number of {mall cubes, the aflortment |
of which will be an imitation of that of the molecule em-
ployed by nature in the formation of the dodecaedron we
are here confidering.

Let ABGF (jig. 7) be a cube compofed of 729 {mall
cubes equal to one another, in which cafe each face of the
whole-cube will contain 81 {quares, nine on each fide, which
will be the external faces of as many partial cubes, reprefenta-
tives of molecule. ‘The cube in queftion will be the nucleus
of the dodecaedron which we propofe to conftru&.

‘On one of the faces, fuch as ABCD of this cube, let us
apply a fquare lamina compofed of cubes equal to thofe
which form the nucleus, but which towards each edge has a
yange of cubes lefs than if it had been on a level with the
adjacent faces BCGH, DCGF, &c. That is to fay, let this

Peo - lamina

Aya st)

4h Theory of Cryffallization. —
lamina be compofed only of 40 cubes, 7 on each fide, in fuch
a manner that if its inferior bafe be on fg (fig. 8), that bafe
may fall exactly on the fquare marked by the fame letters

(4g: 7)-
Above this firfl ‘en ‘na let us apply a fecond compofed of
25 cubes, five on cach fide, fo that if / m pu (fig. g), repre=

fent its lower bale, this bafe may be found fituated exa@ly -

above the fquare defigned by the fame letters (fig. 7).

Let-us, in like manner, apply a third lamina upon the
fecond; but containing only 9 cubes, three on each fide, fo
that v # y z (jig. 10) being the inferior bafe, this bafe may
correfpond with the fquare marked by the fame letters
(fg. 7)» Laftly, on the middle fquare +, in the preceding
Jamina, let us place the fmall cube r (jig.11), whieh will
seprefent the laft.

It may be eafily feen that by this operation we fhall have
formed upon the face ABCD (fg. 7) a quadrangular pyra-
mid, of which this face will be the bafe, and which will have
the cube r (fig. 11) foritsfummit. If we continuethe fame
operation on the other five faces of the cube (fg. 7) we fhall
have, in all, fix quadrangular pyramids, refting on the fix

faces of the nucleus, which they will envelop on all fides..

But as the different courfes or laminz which compole thefe

pyramids projet beyond each other a certain quantity, as —

may be feen fg. 12, where the parts elevated above the planes
BCD, BCG reprefent the two pyramids which reft on the
faces ABCD, BCGH (jg. 7), the faces of the pyramids
will not form continued planes: they will be alternately re-
entering and falient ; and in fome meafure will imitate a
pyramidal afcent of fteps, which prefents four faces (efcalier
2 quatre faces }. :

Let us now fuppofe that the nucleus is compofed of an
imecomparably larger number of cubes, almoft imperceptible;
and that the lamine, applic-l on the different faces, which I
fhall in future call Jamine of /uperpofition, go on increafing

towards their four edges, by fubtractions of one range of .

cubes

a Le ee ee

. Theory of Cryftallization. ag

cubes equal to thofe of the nucleus, the number of thefe
laminz will be found incomparably greater than.in the pre-
ceding hypothefis ; at the fame time the cavities ( cannelures)
which they will form, by the alternate fallying and re-enter-
ing of their edges, will be fcarcely fenfible ; and we may
even fuppofe the compofing cubes fo fmall that thefe cavities
will become imperceptible to our fenfes,. and that the faces
of the pyramids will appear perfectly fmooth.

_Now DCBE (fig. ee being the pyramid refting on
the face ABCD (fg.7), and CBOG (fg. 12) the py-
tamid applied on the neighbouring face BC GH, (fg. 7), if
we confider that every thing is uniform from Eto O (fig. 12)
in the manner in which the edges of the laminz of fuperpofi-
tion mutually project beyond each other, it will readily be
conceived that the face C Eb of the firft pyramid ought
to be found exactly in the fame plane as the face COB of
the adjacent pyramid, fo that the afemblage of thefe two
faces will form a rhombus ECOB._ But for the fix py-
ramids we had twenty-four triangles, fimilar to CEB,
which, confequently, will be reduced to twelve rhombufes,
from which will refult a dodecaedron fimilar to that repre-

‘fented (fig. 5 and 6) ; and thus the problem is refolved.
_ The cube, before it arrives at the form of the dodecae-
_dron, paffes through a multitude of intermediate modifica-
tions, one of which is reprefented fg. 13. It may be there
-fleen that the fquarespaeo, kiqu, mnts, &c. correfpond
to the fquares ABCD, DCG F, CBHG, &c. (fg. 6)
and form the fuperior bafes of as many pyramids, incomplete
for want of the laminz by which they ought to be termi-
Rated. The rhombufes ED LC, E COB, &c.. (fig. 5),
by a neceflary confequence are weduied to fimple hexagons
aeCleD, coBnmG, &e. (fig.-13) and the furface of
the fecondary cryftal is compofed of twelve of thofe hexa-
ons and fix fquares. This is the cafe with the boracic
, allowance being made for fome facets which take the
place

46 (i Obfervations on Iron and Stecl.

ro

place of the folid angles, and which are fubjeét to another —

law of decreafe, to be {poker of hereafter.

If the decreafe of the laminz of fuperpofition took place

according to a more rapid law; if each lamina for example
had had on its circumference two, three, or four tanges of
cubes lefs than the inferior range, the pyramids produced
around the nucleus, by this decreafe, being more lowered,
and their adjacent faces being no longer on a level, the fur-
face of the fecondary folid would be compofed of 24 ifofceles
triangles, all inclined one to the other. I call decreafe on the
edges that which takes place parallel to the edges of the nu-
cleus, as in the preceding examples, to diftinguifh it from
another kind of decreafe which I fhall fpeak of hereafter,

and which takes place according to directions altogether ”

different.
(To be continued. )

XI. Obfervations on Iron and Steel. By FOSEPH COLLIER:
From the Tranfaftions of the Manchefter Society.

[With a Plate, No.TII.]

Arter examining the works of different authors who
have written on the fubject of making iron and fteel, I am
perfuaded that the accounts given by them of the neceflary
procefles and operations are extremely imperfect. Chemifts
have examined and defcribed the various compound mine=
rals containing iron with great accuracy, but have been lefs
attentive to their reduction. This obfervation more parti-
eularly applies to fteel, of the making of which I have not

feen any correct account. It is fingular to obferve how very

imperfectly the cementation of iron lias been defcribed by

men of great eminence in the fcience of chemiftry. Four

croy ftates the length of time neceffary for the cementation
of

Objervations on Iron and Steel. 47

of iron to be about twelve hours; but it is difficult to didlos
ver whether he alludes to caft or to bar fteel: for he fays,
that fhort bars of iron are to be put into an earthen box
with a cement, and clofed up. Now fteel is made from bars
of iron of the ufual length and thicknefs: but caft feel is
made according to the procefs defcribed by Fourcroy, with
this effential difference—the operation is begun upon bar
fteel, and not bar iron.

Mr. Nicholfon is equally unfortunate in the account giver
in his Chemical Didtionary. He fays that the ufual time
required for the cementation of iron is from 6 to 10 hours,
and cautions us againft continuing the cementation too
long ; whereas the operation, from the beginning to the end,
requires 16 days at leaft. In other parts of the operation he
is equally defeCtive, confounding the making of bar with
that of caft fteel, and not fully defcribing either. In {peak-
ing of the ufes of fteel, or rather of what conflitutes its fu-
periority, Mr. Nicholfon is alfo deficient. He obferves that
“ its moft ufeful and advantageous property is that of becom-
ing extremely hard when plunged into water.” He has here
forgotten every thing refpeCting the temper and tempering
of fteel inftruments, of which, however, he takes fome no-
'tice in the fame page. ‘* Plunging into water” requires a
little explanation: for, if very hot fteel be immerfed in cold
water without great caution, it will crack, nay fometimes
break to pieces. It is however neceflary to be done, in order
‘to prevent the fteel from growing foft, and returning to the
ftate of malleable iron; for, were it permitted to cool in the
open air, the carbon which it holds in combination would
be diffipated*. I fhall at prefent confine my remarks to
the operations performed on iron in Sheffield and its neigh-
bourhood, from whence various communications have been
tranfmitted to me by refident friends, and where} have my-
felf feen the operations repeatedly performed. ‘The iron

* It is the opinion of fome metallurgifts, that a partial abftraétion of

@xygen takes place, by plunging hot metal into cold water,
made

48 Obfervations on Iron and Steel.

made in that part of Yorkthire is procured from ores found
in the neighbourhood, which are of the argillaceous kinds
but intermixed with a large proportion of foreign matter.
Thefe, however, are frequently combined with richer ores

- from Cumberland and other places. The ore is firft roafted

with cinders for three days in the open air, in order to expel
the fulphureous or arfenical parts, and afterwards taken to ~
the furnaces, fome of which are conftructed fo that their in-
ternal cavity has the form of two four-fided pyramids joined
bafe to bafe ; but thofe moft commonly ufed are of a conical
form, from forty to fifty feet high. The furnace is charged
at the top with equal parts of coal-cinder and lime-ftones
The lime-flone acts as a flux, at the fame time that it fup-.
plics a fufficient quantity of earthy matter, to be converted
into fcorie, which are neceffary to defend the reduced metal
from calcination, when it comes near the lower part of the
furnace. ‘The fire is lighted at the bottom ; and the heat is
excited by means of two pair of large bellows blowing al-
ternately. , The quantity of air generally thrown into the fur=
nace is from 1000 to 1200 fquare feet in a minute. The
air paffes through a pipe, the diameter of which is from two
inches and a quarter to two and three quarters wide. ~The
compreflion of air which is neceflary is equal to a column
of water four feet anda half high. The ore melts as it
paffes through the fire, and is colleéted at the bottom, where
it is maintained ina liquid ftate. The flag, which falls down
with the fufed metal, is let off by means of an opening in
the fide of the furnace, at the difcretion of the workmen.
When a fufficient quantity of regulus, or imperfectly re-
duced metal, is accumulated at the bottom of the furnace
(which ufually happens every eight hours), it is let off into
moulds, to form it for the purpofes intended, fuch as can-
non or pig iron.—Crude iron is diftinguifhed into white,
black, and grey.“ The white is the leaft reduced, and more.
brittle than the other two; the black is that with which a
~ Jarge quantity of fuel has been ufed; and the grey is that
-g which

Objfervations on Iron and Steel. 49

which has been reduced with a fufficient quantity of fuel, of
which it contains a part in folution. The operation of re-
fining crude iron confifts in burning the combuftible matter
which it holds in folution; at the fame time that the re-
tiaining iron is more perfectly reduced, and acquires a
fibrous texture. For this purpofe, the pigs of caft iron are
‘taken to the forge, where they are firft put into what is called
the refinery ; which is an open charcoal fire, urged by a pait
of bellows, worked by water or a fteam-engine ; but the
compreflion of air in the refinery ought to be lefs than that
in the blaft-furnace. After the inetal is melted, it is let out
of the fire by the workmen to difcharge the fori, and then
returned and fubjected to the blaft as before. This opera-
tion is fometimes repeated two or three times before any
appearance of malleability (or what the workmen call coming
into nature) takes place; this they know by the metal’s firft
affuming a granular appearance, the particles appearing to
repel each other, or at leaft to have no figns of attrac-
tion: Soon afterwards they begin to adhere, the attraction
irigreafes very rapidly, and it is with great difficulty that the
whole is prevented from running into one mafs, which it is ©
defirable to avoid, it being more convenient to ftamp fmall
pieces into thin cakes: thisis done by putting the iron imme-
diately under the forge-hammer, and beating it into pieces
about an inch thick, which eafily break from the reft during
_ the operation. Thefe fmall pieces are then collected and
piled to the height of about ten inches upon circular ftones,
which are an inch thick and nine inches in diameter. They
are afterwards put into a furnace, in which the fire is rever-
berated upon them until they are in a femi-fluid ftate. The
workmen then take one out of the furnace, and draw it into
a bar under the hammer; which being finifhed, they apply
the bar to another of the piles of femi-fluid metal, to which
it quickly cements, is taken again to the hammer, the bar
- firft drawn ferving as a handle, and drawn down as before.
The imperfetions in the bars are remedied by putting them
Vor. I. E into

50 Objervations on Iron and Steel. —

into another fire called the chafery, and again fubjecting
them to the action of the forge-hammer.

The above method is now moft in ufe, and is called flou-
rifhing ; but the iron made by this procefs is in no refpe@
fuperior to that which I am going to defcribe. It is hew-
ever not fo expenfive, and requires lefs labour.

The procefs for refining crude iron, which was moft
common previous to the introduction of flourifhing, is as
follows:

_ The pigs of caft iron are put into the refinery, as above,
where they remain until they have acquired a confiftence
refembling pafte, which happens in about two hours and a
half, The iron is then taken out of the refinery, and laid
upon a caft iron plate on the floor, and beaten by the work-
men with hand-hammers, to knock off the cinders and other
extraneous matters which adhere to the metal. It is after-
wards taken to the forge- hammer, and beaten firft gently, till
it has obtained a little tenacity; then the middle part of
the piece is drawn into a bar about half an inch thick,
three inches broad, and four feet long, leaving at each end
a thick fquare lump of imperfe& iron. In this form it is
called ancony. It is now taken to the fire called the chafery,
made of common coal; after which the two ends are drawn
out into the form of the middle, and the operation is'
finifhed.

There is alfo a third method of rendering crude iron mal+
leable, which, I think, promifes to be abundantly more advan-
tageous than either of the two former, as it will difpenfe
both with the refinery and chafery ; and nothing more will
be neceflary than a reverberating furnace, and a furnace to
give the metal a malleable heat, about the middle of the
operation. The large forge-hammer will alfo fall into difre-
pute, but in its place muft be fubftituted metal rollers of
different capacities, which, like the forge-hammer, muft be
worked cither by a water-wheel or a fteam-engine.

It is by the operation of the forge-hammer or metal

rollers,

Obfervations on Iron and Steel. 51
follers, that the iron is deprived of the remaining portion of
impurity, and acquires a fibrous texture.

The iron made by the three foregoing proceffes is equally
valuable, for by any of them the metal is rendered pure; but
after thofe different operations are finifhed, it is the opinion
of many of the moft judicious workers in iron, that laying
it ina damp place for fome time improves its quality ; and
to this alone fome attribute the fuperiority of foreign iron,
more time elapfing between making and ufing the metal.
To the latter part of this opinion [ can by no means accedey
as itis well known that the Swedifh* ores contain much
lefs heterogenéous matter than ours, and are generally
much richer, as they ufually yield about 70 per quintal of
pure iron, whereas the average of ours is not more than
30 of 40+: add to this, that the Swedifh ores are {melted
in wood fires, which gives the iron an additional fuperiority.

Iron inftruments are cafe-hardened by heating them ina
cinder or charcoal fire; but if the firft be ufed, a quantity of
old leather or bones muft be burnt in the fire, to fupply the
metal with carbon. The fire muft be urged by a pair of
bellows to a fufficient degree of heat, and the whole opera-
tion is ufually completed in an hour.

The procefs for cafe-hardening iron is in fact the fame as
for converting iron into fteel, but not continued fo long, as
the furface only of the article is to be impregnated with car=
bon. Some attempts have been made to give caft-iron, by
cafe-hardening, the texture and ductility of fteel; but they
have not been very fuccefsful. Table and pen-knife blades
have been made of it; and, when ground, have had a pretty
good appeararice ; but the edges are not firm, and they foon
lofe their polifh. Common table knives are frequently made
of this metal. The cementation of iron converts it into

* Steel is commonly made of Swedifh iron.

4 The iron made from the oré found in the neighbourhood of Sheffield
sontains a great deal of phofphate of iron or fiderite, which renders the
metal brittle when cold.

E2 fteel,

§2 Obfervations on ‘Tron and Steel.

fteel, a fubftance intermediate between crude and malleable
iron.

The furnaces for making fteel are conical buildings ; about
the middle of which are two troughs of brick or fire-ftone,
which will hold about four tons of iron in the bar. At the
bottom is a long grate for fire. The fteel furnace, how-
ever, is not well adapted for defcription. I fhall therefore
avail myfelf of an accurate drawing, which was communi-
cated to me by a gentleman converfant with the manufacture,
and which is copied in the plate. A layer of charcoal-duft
is put upon the bottom of the trough, and upon that a layer
of bar iron, and fo onalternately until the trough is fall. It
is then covered over with clay to keep out the air; which, if
admitted, would effe€tually prevent the cementation. When
the fire is put into the grate, the heat paffes round by means
of flues, made at intervals, by the fides of the trough. The fire
is continued until the converfion is complete, which gene-
rally happens in about eight or ten days. There is a hole in
the fide, by which the workmen draw out a bar occafionally,
to fee how far the tranfmutation has proceeded. This they
determine by the blifters upon the furface of the bars.

If they be not fufficiently changed, the hole is again clofed
carefully, to exclude the air; but if, on the contrary, the
change be complete, the fire is extinguifhed, and the fteel is
left to cool for about eight days more, when the procefs for
making bliftered fteel is finifhed. For fmall wares, the bars
are drawn, under the tilt hammer, to about half an inch
broad and 3, of an inch thick. The change wrought on
bliftered fteel by the tilt hammer, is nearly fimilar to that
effected on iron from the refinery by the forge hammer. It
is made of a more firm texture, and drawn into convenient
forms for ufe. German fteel is made by breaking the bars
of bliftered fteel into {mall pieces, and then putting a num-
ber of them into a furnace ; after which they are welded to-
gether and drawn to about eighteen inches long; then dou-
bled and welded again, and finally drawn to the fize and fhape

7 required,

Obfervations on Iron and Steel. 53

required for ufe. This is alfo called fhear fteel, and is
fuperior in quality to the common tilted fteel. Caft fteel

isalfo made from the common bliftered fteel. The bars are

broken, and put into large crucibles with a flux. The cru-
cible is then clofed up with a lid of the fame ware, and placed
in a wind furnace. By the introduction of a greater or
fmaller quantity of flux, the metal is made harder or fofter.
When the fufion is complete, the metal is caft into in-
gots, and then called ingot fteel ; and that which afterwards
undergoes the operation of tilting, is called tilted caft fteel.
The caft fteel is the moft valuable, as its texture is the moft
compact, and it admits of the fineft polifh. Sir T. Frankland
has communicated a procefs, in the Tranfa€tions of the Royal
Society*, for welding caft fteel and malleable iron together ;
which, he fays, is done by giving the iron a malleable, and
the fteel a white heat ; but, from the experiments which
have been made at my requeft, it appears, that it is only foft
caft fteel, little better than common fteel, that will weld to
iron: pure fteel will not; for, at the heat defcribed by Sir
T. the beft caft fteel either melts, or will not bear the ham-
mer. It may here be obferved, as was mentioned before,
that fleel is an intermediate ftate between crude and malle-
able iron, except in the circumftance of its reduction being
complete ; for, according to the experiments of Reaumur
and Bergman, fteel contains more hydrogen gas than caft
iron, but lefs than malleable iron ;—lefs plumbago than the
firit, but more than the latter ;—-an equal portion of man-
ganefe with each ;—lefs filiceous earth than either ;—more
iron than the firft, but lefs than the fecond. Its fufibility is
likewife intermediate between the bar iron andthe crude.
When fteel has been gradually cooled from a ftate of igni-
tion, it is malleable and foft, like bar iron; but when ig-
nited and plunged into cold water, it has the hardnefs and
brittlenefs of crude iron. From the foregoing facts we are
juftified in drawing the fame conclufions with Reaumur and
* Phil. Tranf, 1795,
E3 Bergman,

54. — Obfervations on Iron and Steel.

Bergman, but which have been more perfectly explained by
Vandermonde, Berthollet, and Monge, that crude iron is a
regulus, the reduétion of which is not complete ; and which
confequently will differ according as it approaches more or
lefs to the metallic ftate. Forged iron, when previoufly well
refined, is the pureft metal; for it is then the moft malle-
able and the moft dudtile, its power of welding is the greateft,
and it acquires the magnetic quality fooneft. Steel confifts
of iron perfectly reduced and combined with charcoal ; and
the various differences in bliftered fteel, made of the fame
metal, confift in the greater or lefs proportion of charcoat
imbibed. Iron gains, by being converted into fteel, about
reo part of its weight. In order to harden fteel, it muft be
put into a clean charcoal, coal or cinder fire, blown to a
fufficient degree of heat by bellows. The workmen fay,
that neither iron nor iteel will harden properly without a
blaft. When the fire is fufficiently hot, the inftrument in-
tended to be hardened muft be put in, and a gradual blaft
from the bellows continued until the metal has acquired a
regular red heat: it is then to be carefully quenched in
cold water. If the fteel be too hot when immerfed in wa-
ter, the grain will be of a rough and coarfe texture ; but if
of a proper degree of heat, it will be perfectly fine. Saws
and fome other articles are quenched in oil. Steel is tem-
pered by again fubjeCting it to the a€tion of the fire. The
inftrument to be tempered we will fuppofe to be a razor
made of cafl fteel. Firft rub it upon a grit ftone until it is
bright, then put the back upon the fire, and in a fhort time
the edge will become of a light ftraw colour, whilft the back
is blue. The ftraw colour denotes a proper temper, either
for a razor, graver, or pen-knife. Spring knives require a
dark brown; {ciffars alight brown or ftraw colour; forks or
table-knives a blue. The blue colour marks the proper tem-
per for {words, watch-{prings, or any thing requiring elafti-
city. The fprings for pen-knives are covered over with oil
before they are expofed to the fire to temper.

Eas’ 3 Expla-

Obfervations on Tron and Steel. 55

Explanation of the Plate.

Fig. 1 is a plan of the furnace, and fig. 2 is a feclion of it
taken at the line AB. The plan is taken at the line CD.
The fame parts of the furnace are marked with the fame let-
ters in the plan and in the feCtion. EE are the pots or
troughs into which the bars of iron are laid to be converted.
F is the -fire-place; P the fire-bars; and R the afh-pit.
GG, &c. are the flues. HH is an arch, the infide of the
bottom of which correfponds with the line III, fig. 1, and
the top of it is made in the form of a dome, having a hole
in the centre at K, fig. 2. LL, &c. are fix chimneys. MM
is a dome fimilar to that of a glafs-houfe, covering the whole.
At N there is an arched opening, at which the materials are
taken in and out of the furnace, and which is clofely built
up when the furnace is charged. , At OO there are holes in
each pot, through which the ends of three or four of the bars
are made to project quite out of the furnace. Thefe are for
the purpofe of being drawn out occafionally to fee if the iron
be fufficiently converted.

The pots are made of fire-tiles or fire-ftone. The bot-
toms of them are made of two courfes, each courfe being
about the thicknefs of the fingle courfe which forms the out-
fides of the pots. The infides of the pots are of one courfe,

- about double the thicknefs of the outfide. ‘The partitions of

the flues are made of fire-brick, which are of different thick-
nefles, as reprefented in the plan, and by dotted lines in the
bottom of the pots. ‘Thefe are for fupporting the fides and
bottoms of the pots, and for direCting the flame equally .
round them. The great object is to communicate to the
whole an equal degree of heat in every part. The fuel is put
jn at each end of the fire-place, and the fire is made the
whole length of the pots, and kept up as equally as poflible.

E4 XIL. Account

rok. :

XU. Account of a Violet Dye produced from the Leaves of Succoe
trine Aloes, which refifts the Aétion of Oxygen, Acids and Al-
kalis. By Mr. Fasproni. Fromthe Annales de Chimie,
Vol. XXV.

To increafe the number of dyeing fubftances, and to be
able to vary the tone and fhades of the different known
colours, is an object of no fmail utility. Several manufac-
tures, as is well known, have been indebted for their reputa-
tion and credit to the poffeffion of,a particular dye.

Without fpeaking of the Tyrian purple, who is ignorant
how much value the modern fcarlet has given to the Dutch
cloths and to thofe of the Gobelins? Who does not know
that the beautiful black of Florence, which has never yet
been imitated, has raifed the Florentine ftuffs all over Europe
toa price to which that of no other country ever attained ?

Scarlet and black belong to that clafs of colours called
noble or fixed, becaufe they are not fufceptible of being ftained,
and becaufe they experience no alteration either from the air
or from light. The beautiful red colour alfo given to filk by
faffower is reckoied among the noble colours, though it
does not withftand the influence of thefe twa Fass: which
foon deftroy it or render it pale.

All other red dyes for filk, in order to be durable, muft be
compofed, in part, of cochineal, which is a colouring fub-
ftance exceedingly conftant.

Argol and all the other lichens produce a very beautiful
violet; but the fun alters thig colour and makes it turn
blue.

I am of opinion, therefore, that if means could be dif-
coyered to compofe, without cochineal, colours graduated
fromm the moft delicate to the darkeft violet purple, which
might be proof agajnft the a€tion of acids and of the air, ine
finite advantages would thence refult to the manufadturers of
cloth and to the public, :

— “7 <

A Dye from the Leaves of the Aloe. SY

Tt was in hopes of difcovering fuch a colour that I dire&ted
my refearches towards a fubftance which hitherto has not
been ranked among thofe called colouring fubftances.

I was perfuaded that, the matter of tke brilliant colours
prefented to usin thofe fruits, flowers, and plants, which
have undergone a fpontaneous alteration, pre-exifts in the
mafs of the fluids that circulate in thofe organs, where it is
difperfed or concealed ; and that to be able to turn it to ade
vantage, nothing would be wanting but a method to feparate
it, and to modify it ina proper manner.

The cochineal infet, which lives on the nopal (caus coce
cenilifer), can extract with its probofcis the red juice, or juice
fufceptible of becoming red, of that plant ; which afterwards
communicates its colour to the infeét, and which, in my
opinion, is the fame as that exhibited to us naked in the ripe
fruit of the fame plant.

The beautiful fcarlet colour affumed by the dead leaves of
fome fpecies of ftrawberry blite (d/itum) is not perhaps
brought forwards but in confequence of the decompofition
of the dead leaf. Would it be impoflible then for art to
feparate this colour, and to modify it in the like manner ?

Having obferved that the fucculent leaves of the ale /uc-
cotrina anguftifolia, as they dried on the plants, aflumed an
agreeable violet colour, I tried to feparate the colouring mat-
ter, or principles of that fine colour, from rhe living leaves.

I found by experiments, that acids as well as alkalis
fpeedily gave to this almoft colourlefs juice a red colour, and
formed a fucceffive precipitation of colouring moleculz

- which had the fame colour.

Oxygen gas produced the like effe&; and it is highly
pleafing to fee how the juice of aloes, merely by being ex-
pofed to the air, with or without the contact of the light,
fucceflively reddens, beginning at the parts more immediately
in contaét, and is gradually converted into a very dark and
lively violet purple.

as This

58 A Dye from the Leaves of the Moe.

_ This juice then produces a fuperb tranfparent colour with~
out body, highly proper for works in miniature, and which
when diilolved in water may ferve alfo, either cold or warm,
for dyeing filk from the lighteft to the darkeft fhade.

Silk, even without a mordant, {trikes and becomes impreg-
nated with this dye. It is equally attracted by fulphurated
filk, though the latter is fo little difpofed to aflume any colour
whatever.

The aloe, indeed, is not a plant indigenous in our climates ;
but this is an inconvenience which it has in common with
almoft all fubftances ufed for dyeing, and even witha great
number of thofe which ferve us as food. ‘Ihe juice might
be procured from Socotora itfelf, not fuch as it is found in
commerce infpiffated by fire, but dried in the air, or prepared
by an acid,

Befides, as this plant grows without any difficu!ty in our
botanical gardens, we may hope to multiply it enough by
cultivation, particularly in the fouthern parts of Italy, in
order to extract from it the juice ourfelves.

The value of this new colour may be readily difcovered,
when we obferve that, by its property of not being altered
by acids or alkalis, it pofleffes the uncommon quality of not
being fufceptible of becoming fpotted.

When we confider alfo that the oxygen, which difcolours
our cloths and filks fo as to render them white, is, as one
may fay, the principle which develops the colour of the aloe;
it ought to be inferred, that the air cannot alter a quality
which it communicates itfelf; and we may therefore con-
elude, that we have difcovered in the aloe one of the mo
durable colours known in nature,

Alll, 4

*

[ 59 J

AIW. A curfory View of fome late Difcoveries and Improvements
in different Branches of Science. Extraéted chiefly from DE
LA Meruerre’s Introdudion to the Journal de Phyfique
for 1798.

Maruematics.

Tu IS fublime part of knowledge, theugh carried in all
appearance to its utmoft extent, ftill continues to make
fome progrefs. Lagrange has finifhed a very important
work, which he began feveral years ago, entitled, Tse Theory
of the Analytical Funttions, Sc. in which he fhews that
every thing hitherto called the differential calculus, whe-
‘ther one follows the method of Leibnitz or that of Newton,:
may be reduced to the ordinary calculation of finite quan-
tities.

Astronomy. Herfchel, who has paid great attention to
the fpots of the fun, confiders that luminary as fimilar to the
planets, and not a flaming body. It contains mountains,
fome of which he fuppofes to be 200 leagues in height. Its
atmofphere is compofed of different elaftic fluids, fome of
which are luminous or phofphoric, and others only tranf-
parent. The former make the fun appear like a mafs of
light or fire; but the parts of that atmofphere which are
only tranfparent, fuffer his body to be feen. ‘Thefe are the
fpots. He believes the fun to be inhabited like the other
planets. .

Lalande, on the other hand, thinks that the fun is really
a folid body, but that his furface and part of his mafs are
compofed of anincandefcent fluid. ‘This fluid, by any move- _
ment, leaves uncovered fometimes a portion of the body of
the fun or his mountains, and thefe are the fpots. Wilfon
confiders the {pots of the fun as eruptions or volcanoes.

Shroeter has fhown that in Venus there are very high
mountains, as ig the cafe on the earth and in the moon.
The greater part of thefe mountains in Venus, like thofe of

60 —- View of fome late Difcoveries and Improvements

the moon, are in the fouthern part of that planet, while on
the earth the greater part of the mountains are towards the
north. The day in Venus appears to that aftronomer to be
23 hours 21 minutes. It differs therefore very little from
the fidereal day of the earth, which is 23 hours 56 minutes
4 feconds.

The volcano of the moon has been feen feveral times by
the naked eye. Caroché faw it at Paris on the fecond of
March 1797. It exhibited the appearance of a candle juft
going out. It refembled a brilliant {pot lefs fenfible than the
greateft fatellite of Jupiter, but larger. Its exiftence there-
fore can no longer be doubted.

La Place has publifhed an excellent memoir on the
movements of the moon.

Hennert fays that the diurnal movement of the earth
may undergo fome variations; but that its variations are
compenfated in fuch a manner, that they may be confidered
as uniform.

Herfchel has obferved around Saturn a quintuple belt of
fpots. By thefe means he has fhown the length of the day
of that planet, and determined its diurnal rotation, which he
eftimates at 10 hours 16 minutes 2 feconds.

Lalande calculated the orbit of the 83d comet to the
month of December 1793; but an 84th comet was feen by
Bode at Berlin, on the rith of November 1795, near the
conftellation of Hercules. It was feen alfo by Bouvard, at
Paris, on the 14th of the fame month. It was fmall, had no
tail, and was not vifible to the naked eye. Its orbit has been

calculated by Zach. It was in its perihelion on the 14th of-.

December at 15 hours 32 feconds mean time at Gotha. Its
diftance then from the fun was 0,22.
An 85th comet was difcovered in Virgo by Olbers, at
Bremen, who calculated its orbit.
An 86th was difcovered from the obfervatory at Paris, by
Bouvard, on the 14th of Auguft 1797, at ten o’clock at
“night. It was feen next day, at Leipfic, by Rudiger. It was
feen

A

~~ 2

in different Branches of Science. . 61

feen alfo by various aftronomers in other places. It paffed
the earth fix times nearer than the fun, which was the caufe
of its apparent motion being very rapid. It was fmall, ap-
peared only like a faint white {pot, and had no tail. Zach,
at Gotha, makes the number of the comets now known to
be go. ;

One of the moft difficult labours of aftronomy is what re-
lates to the ftars. Their immenfe number indeed is fufficient
to deter any one from the tafk of numbering them; for
thofe which we fee, and we are far from feeing them all,
may be eftimated at more than a hundred millions, Many
of thefe it is well known have peculiar motions, fome of
which are very confiderable. It is to them, however, that
we are obliged to refer all the motions of the fun, the pla-

nets, andthe comets. It is of importance then to endeavour

to determine the motions of the ftars; and this objeé&t has
at all times engaged the attention of aftronomers. Mafke-
lyne has determined with the utmoft precifion the pefition
of 34 ftars. Zach has accomplithed the fame thing in re-
gard to 1200. Lalande, with his nephew and niece, have
undertaken a labour far greater, to determine the pofition
of more than 40,000 ftars, from the arétic pole to the tropic

of capricorn. This fublime tafk is already very much ad-

vanced, as the pofitions of 42,700 are already known.

Hyprostarics.—Venturi has made interefting experi-
ments on the lateral efflux of fluids. He fhews that the
efflux is more confiderable, when a pipe, rather a little long,
is adjufted to the aperture of the veffel, than when there is
no pipe, or only one that is fhort. Thus, when one withes
to draw wine, the jet will be more confiderable by putting
a cock into the aperture of the cafk, than if there were
no cock; and if the cock be fome inches in length, the
quantity that flows out will be greater than if it were very
fhort, —

It is well known, that when fmall bits of camphor and
other fubftances, fuch as the juice of the euphorbium, are
Placed upon water, they appear agitated in a very remark.

able

62 View of fome late Difcoveries and Inprovementt

able manner. Romieu afcribed this phenomenon to eleétris
city, but Volta has proved that eletricity has no connec=
tion with it. Lichtenberg was of opinion, that camphory
lofing a great deal by evaporation, continually decreafes in
bulk, and that thefe {mail fragments of it change their con-
figuration, which makes a variation in their refpeétive at-
tractions. Volta thinks that the vapours which exhale from
thefe bodies {trike the air and the water with fufficient force
to caufe the moleculz, from which thefe vapours are exhaled,
to be agitated as above mentioned.

Brugnatelli has convinced himfelf that this phenomenon
takes place with all fubftances that contain much effential
oil, fuch as the leaves of laurel, fage, thyme, vanilla, the nut-
meg-tree, the rus toxicodendron (the poifon oak), the rhus
vernix (the voifon-ath). He found alfo that {mall bodies
which did not move on the water acquired that property
after being impregnated with effential oil. A piece of bread,
for example, rubbed againft a piece of lemon-peel and im-
pregnated with eflential oil of lemons, moved, aiter being
placed upon water a little warm.

Thefe experiments prove that it is jects of effential oil
thrown out with rapidity from thefe bodies, which make
them move on the water. Thefe jets experience a refiftance
from the air and the water, as a lighted rocket experiences a
refiftance from the air by which it is made to afcend; that
is to fay, in a direction oppofite to the jet of the flame.

Venturi, who repeated all thefe experiments, made fevéral
{mall flicks of camphor, which he placed on water, adding to
_them a bit of lead by way of ballaft. They all moved as ufual;
but he obferved them become a little {maller above the fur-
face of the water, and at length break intwo. ‘This effect
is more fpeedy if the water be a little warm, and is occas
fioned by the continual evaporation of the: parts.

Borany.— Though the number of plants is fo confider-
able, being eflimated at about twenty thoufand, that the moft
retentive memory can fcarcely remember their. names, the
ardour for this branch of fcience does not feem to decreafe.

6 ; La

eee tue:

in different Branches of Science. 63

La Billardiere, who went round the world with d’En-
trecafteaux, brought back with him a valuable collection in
every part of natural hiftory. His herbal is moft beautiful ;
and though nearly one fourth of it has been loft, he has ftill
about three thoufand plants, of which from twelve to fifteen
hundred are new.

He carried with him from the Friendly Ifles twenty-two
bread-fruit-trees, twelve of which were left at the Ifle de
France. Of the eight brought to France, five died ; two
haye been fent to Cayenne; and the other was brought to
Paris, where it is now in the Jardin des Plantes.

La Billardiere brought with him alfo about three hun-
dred birds, a third of which almoft are unknown. His
colleGtion of infects has been much damaged ; but he has
ftill a great many in fuflicient prefervation to be defcribed.
Riché, who went on the fame expedition, brought with
him a variety of objects, and particularly birds. He died
not long ago.

Michau. has returned from South America, and brought
with him a great number of plants in excellent prefervation.
He will no doubt foon publith an account of them, as well
as of thofe which he brought from Perfia.

Coulomb having ordered fome poplars to be cut down in
the fpring time, obferved, that when the axe approached
the centre of the tree, a very large quantity of air was dif-
engaged, but that none was difengaged when the inftrument
‘attacked the other parts of the tree. It is well known that
the medullary part, in which the air circulates particularly,
is fituated towards the centre. From this medullary part
proceed thofe tranfverfal veflels which extend to the bark of
the tree for the circulation of the air. The plant contains
alfo other veffels for the circulation of the fap.and of all the
vegetable juices. There are alfo glands where the fecretion of
all thefe different liquors is performed to produce the propolis,
pollen, fc. A vegetable, therefore, in the fimpleft cafe, may
be confidered as an aflemblage of feveral pliable elaftic fibres,

compofing

Gx View of fome late Difcoveries and Iinprovements
compofing a great number of veffels of different calibress in
which water, air, and various kinds of fluids drawn from
the bofom of the earth and the atmofphere, circulate.

Light alfo has a great iufluence on vegetation. Hum-
boldt has fhown that the light of a lamp may, in this re-
fpeét, fupply that of the fun; and that plants which receive
the light of a lamp are coloured green, as if they received
that of the fun. Excefs of light hurts plants, efpecially
when they begin to rife.

According to Ingenhouz, plants fuffer oxygen to be dif-
engaged in the light, and the carbonic acid in darknefs.
Senebier i8 of opinion that the latter changes the oxygen in-
to the carbonic acid, by furnifhing it with carbon.

Humboldt has obferved that mufhrooms furnifh hydro-
genous gaz in the day, as well as the night-time.

MepicineE.—The carbonate of barytes and pure cauftie
barytic earth are moft active poifons. Pelletier killed feveral
dogs by making them take from twelve to eighteen grains
of thefe fubftances.

Mankind have been long employed in attempting to dif- |
cover means for the prolongation of life. alli, after lay-
ing down principles well known, viz. that old age comes on
naturally, becaufe the calcareous phofphate or calcareous
carbonate is continually accumulating in the greater part of
the folids, fuch as the bones, the arteries, veins, tendons,
&c. fays, that this accumulation can be guarded againft
only two ways; either by preventing that fubftance from
being formed in the mafs of the fluids, or by expelling it as
foon as it is formed.

1. To prevent too abundant a production of that earth,
one muft ufe aliments which contain the leaft quantity of
it, fuch as vegetables, milk, fith (but fifhes contain a great-
deal of the phofphoric acid).

2. The means which he thinks moft proper for expel-
ling that calcareous earth, or calcareous phofphate, are,
bathing, fri€tions, diuretics, pure water, and beverages cooled

with

in different Branches of Science. 65
with ice. In fhort, he confiders the oxalic acid given in
{mall dofes as the beft remedy. That acid, fays he, decom-
pofes the calcareous phofphate : the oxalate of lime which
thence refults will be carried into the torrent of circulation,
and will be driven outwards.

Vauquelin and Brogniard have proved that the acetic acid
diffolves the vegetable gluten and the animal fibres.

It is well known that there is a difeafe called by nofologifts
malacofteon, or mollities offium, where the bones become entirely
foft. ‘The caleareous phofphate is almoft entirely carried
away, and there fcarcely remains any thing but the cellular
tiffue of the bones, with the gelatinous and greafy part, or

the marrow. Were it poflible to find out the means of dif-
folving, gradually, in this manner the calcareous phofphate,

without depriving the bones of their folidity, and without
hurting the other animal fundtions, the fountain of youth
would be difcovered. It appears therefore that it may not
be altogether impoilible to retard age at leaft.

PuystoLocy.—Spallanzanihaving deftroyed theeyes of bats
and fet them at liberty in an apartment, obferved that they
could guide themfelves from one place to another as before.
They avoided every obftacle that was prefented to them,
and even paffled through rings which he placed before
them: and for this reafon he afks, “* May not thefe animals
poffefs a fenfe with which we are not acquainted, and which
may fupply that of fight? or, May not {mell be fufficient
for that purpofe ?”

Jurine is of opinion that it is hearing which fupplies the
above want. He filled with wax one of the ears of thofe

animals which he had deprived of fight, and he obferved that
‘they flew about with difficulty; when he filled both their

ears, they could not fly at all.

{Lo be continued.

Ot. 3. F XIV. An

[ 66 ]
XIV. An Account of two fingular Meteors.

A LUMINOUS body was obferved in the canton of
Calvire, on the evening of the 8thof March laft. Ttappeared
to dire€t its courfe from the eaft to the weft, traverfing the
heavens from Calvire to Mont-d’Or, where it fell. It made
itfelf be diftinguifhed in its courfe by a noife like that of a
long and violent difcharge of mufketry. Lalande has pub-
Jifhed the following note refpeCting thefe fingular meteors ;

“ One frequently obferves,” fays he, “ globes of fire in the
atmofphere. I have mentioned above. 36 inftances of that
kind in the Connoiffunces des Temps for the year 1779. — That
obferved on the 18th of Ventofe (March 8) in the depart-
. ment of Ain, at feven in the evening, was attended with
tome fingular circumftances. The heavens were ferene,
and a large globe, as big as the moon, was feen to proceed
from the eaft, and to advance with a rapid motion towards
the weft. It was followed by a train of light, the rays of
which, colleéted into bundles, were terminated by fmall
globes. Six or feven fprigs of ftars were feen-on each fide
of the train. - At the end of fome feconds there was an ex-
plofion like a lengthened clap of thunder, or the loud report
ofacannon. This meteor diffufed fuch a light that day
feemed to have returned, and people in dark apartments
could fee each other.

“¢ This globe was at fuch a diftance, that it could be feen,
at the fame time, in places feven or eight leagues afunder.
A defcription of it was fent to me by citizen Riboud, at Jof-
feran, and citizen Langeron, at Thorfey. Had it been ata
greater diftance, it would have appeared only like thofe falling
ftars which are obferved fo frequently. The common caufe
of thefe phenomena appears to be hydrogenous gas, fet qn
fire, by fome means, in the atmofphere.”

On the 25th of March the following curious phenomenon
was obferved at Niort: Between the hours of fix and eight
in the morning the fun appeared accompanied by two radi-

ant

Account of two Meteors. 67

ant circles refembling two other funs, one on the right and
the other on the left, and which with the real fun as a bafe
feemed to compofe a triangle. Thefe two fupernumerary
funs were fo exceedingly bright, that it was impoflible to keep
the eyes fixed on them for any length of time. They dif-
appeared gradually ; that on the eaft difappeared firft, and
at the end of two hours they were both invifible.

The wind for ten days had been E.N.E., and a cold much
grezter than ufual for the feafon had fome days before fuc-
ceeced mild weather accompanied with a little rain. On the
18th of March the mercury in the barometer had fallen to
26,8, On the 20th of the fame month there were ‘feveral
heavy fhowers of large hail at different times. On the 24th
the de€trical rivChane emitted very {trong {parks almoft
without being folicited ; and at the time when the phenome-
non appeared, a few clouds fcarcely perceptible were to be
feen in the high regions of the atmofphere.

Phenomena of the above kind, though not frequent, have
been feen at different periods. Auguftine takes notice of
two mock funs which were feen before the chriftian wera,
Zonaras mentipns two feen after the death of Chrift, Pal-
merius three feen in 1466, Surius three funs, i. e. two par-
helia feen at Wirtenberg in 1514, Fromundus three funs
{een in 1619, Cardan thtee at Venice in ieee

In Britain, if we may credit our old chronicles, five funs
were plainly feen at one time, and a great diftance from one
another, in the year 346: three were feen in 812; three
in 9533 and five in 1233. Lilly mentions three feen on
the 19th of November, 1644; and three feen on the 28th
of February, 1648. A moft remarkable phenomenon of this
kind, where five parhelia were feen at once, is mentioned
in the 8th volume of the New Tranfaétions of the Imperial
_ Academy at Peterfburg; an account of which, with an
engraving, will be given in a fubfequent number.

F2 XV. On

PEGs)

XV. Ona new Acid procured from Animal Subftances, called the
Zoonic Acid. By Mr. BERTHOLLET. From the Annales
‘ de Chimie, Vol. XXVI.

ry7zs

ii HE liquid procured by diftillation from animal fub-
ftances has appeared hitherto to contain only carbonate of
ammoniac and an oil; but I have found in it an acid, to
which I have given the name of the zoonic acid. I obferved
this acid in the liquid obtained from the gluten of wheat,
the yeaft of beer, bones, and woollen rags, diftilled for the
preparation of the muriate of ammoniac. I think myfelf
therefore authorifed to confider it as produced by the diftil-
lation of all animal fubftances.

To feparate this acid, I mix quicklime with the difiilled
liquid afier having feparated the oil, and then boil or diftil
the mixture. The carbonate of ammoniac is exhaled; and
when the odour ceafes to be fharp (piquant), I filter, and
add a little quicklime to the liquid, which I boil again, till
the fmell of the ammoniac goes off entirely. "What remains
is Zoonate of lime, which I filter again. I then pour upon —
it water impregnated with carbonic acid, or I blow into the
fiquid with my mouth, through a tube, in order to precipi-
tate, by the carbonic acid of the refpired air, the quicklime
which may be held’ in folution without being combined.
Zoonate of lime may therefore be employed to effect com-
binations by complex affinities ; but to obtain the zoonic
acid pure I make ufe of the following procefs: I mix the
folution of zoonate of lime in water, made pretty ftrong
(rap: rochce) in a tubulated retort with the phofphoric acid ;
I then diftil it. The diftillation, as the zoonic acid has
very little volatility, requires a degree of heat nearly equal
to that of boiling water. ‘The liquor muft then be made to
boil. If two veffels be adapted, one after the other, nothing
will pafs into the fecond. It appears that a part of the acid
is deftroyed by the a€lion of the heat; for the liquid which

1S

@o 4

Memoirs of the late P. Nieuwland. 69

is in ebullition becomes brown, and grows black at the end
. of the operation. It may thence be concluded that. this
acid contains carbon. I have not been able to collect the
other principles which are difengaged during the decom-
pofition.

The zoonic acid has an odour like that of meat when
Frying, and is indeed formed during that procefs. It has an
auftere tafte. I have been able, as yet, to make on this acid
only a {mall number of experiments, which exhibited no
remarkable property. It gives a {trong red colour to paper
tinged with turnfol, and produces an effervefcence with al-
kaline carbonates. It did not appear to me to produce with
alkaline and earthy bafes {alts which cryftallize. It forms a
white precipitate in a folution of acetite of mercury in wa-
ter, and in that of the nitrate of lead; fo that it has more
affinity with the oxyde of mercury than the acetous acid,
and with the oxyde of lead than the nitric acid. It acts
on the nitrate of filver only by complex affinity ; and the pre-
Cipitate it then forms grows brown with time, which fhews
that this precipitate contains hydrogen. The zoonate of
potath calcined did not form pruffiate of iron with a folution
of that metal.. A liquid, which had all the indications of
acidity, feparated from flefh which I kept a long time in a
ftate of putrefation, but it was an ammoniacal falt with
.excefs of acid: this acid combined with lime appeared to me
like zoonate of lime; but I had too little of it to eftablith
exactly its identity with the zoonic acid.

XVI. Biographical Memoirs of the late PrtER NIEUWLAND.
From his Eloge read at Amfterdam, Nov. 24; 1794, in the
Society Felix Meritis.

ees NiEUWLAND, profeffor of mathematics and natural
philofophy in the univerfity of Leyden, was born at Diemer-
F3 meer,

40 Biographical Memairs

meer, a village near Amfterdam, on the sth of Novembir,
1764. His father, by trade a carpenter, having a great font-
nefs for books, and being tolerably well verfed in the mathe-
matics, inftructed his fon himfelf till he attained to his
eleventh year. Young Nieuwland appears to have difplayed
ftrong marks of genius at a very early period. When about
the age of three, his mother put into his hands fome prints by
John Luiken, which had fifty verfes at the bottom of them
by way ofexplanation. Thefe verfes fhe read to him aloud,
without any intention that her fon fhould learn them; and
fhe was much furprifed fome time after to hear him repeat
the whole from memory with the utmoft correctnefs, on being
only fhewn the prints. Before he was feven years of age
he had read more than fifty different books, and in fuch a
manner that he could frequently repeat paflages from them
both in profe and in verfe. When about the age of eight, Mr.
Aenex at Amfterdam, one of the greateft calculators of the
age, afked him if he could tell the folid content of a wooden
ftatue of Mercury which ftood upon a piece of clock-work.
“ Yes,” replied young Nieuwland, ‘* provided you give me a
bit of the fame wood of which the ftatue was made ; for I
will cut a cubic inch out of it, and then compare it with the
flatue.” Poems which difplay the utmoft livelinefs of ima-
gination, and which he compofed in his tenth year, while
walking or amufing himfelf near his father’s houfe, were,
though written at fo tender an age, received with admiration
and inferted in different poetical colle€tions.

Such an uncommon genius muft foon burft through thofe
obftacles which confine it. Bernardus and Jeronimo de
Bofch, two of the firft and wealthieft men at Amfterdam,
became young Nieuwland’s benefactors, and contributed very
much to call forth his latent talents, and to enable the
powers of his mind to expand. He was taken into the
houfe of the former in his eleventh year, and he received
daily inftru€tion from the latter for the fpace of four
years. While in this fituation he made confiderable pro-

grefg

of the late P. Miewwland. a1

grefs in the Latin and Greek languages, and he ftudied
philofophy and the mathematics under Wyttenbach. In the
year 1783 he tranflated the two differtations of his celebrated
inftru€tors, Wyttenbach and de Bofch, on-the opinions
which the ancients entertained of the ftate of the foul after
death, which had gained the prize of the Teylerian theologi-

cal fociety.
From the month of September 1784 to 1785, Nieuwland
refided at Leyden as a ftudent in the univerfity, and after-
wards applied with great diligence, at Amfterdam, to natural
philofophy and every branch of the mathematics, under the
dire@tion of Profeffor van Swinden. In thefe purfuits, in-
deed, he had fearcely any occafion for a mafter ; for he pof-
feffed the peculiar talent of uniting different fciences, and
of comprehending their principles with the utmoft facility.
He had fcarcely begun to turn his attention to chemiftry,
when he made himfelf mafter of the theory of the much-
lamented Lavoifier, and could apply it to every phenomenon.
He could read a work through with uncommon quicknefs,
and yet retain in his mind the principal part of its contents.
Nieuwland’s attention was dire€ted to three principal pur-
fuits: poetry, the pure mathematics, and natural philofophy.
In the latter part of his life he added to thefe alfo aftronomy.’
Among the poems which he publifhed, his Orion alone has
rendered his name immortal in Holland. Of the {mall ef-
fays which he publithed in his youth, the two following are’
particularly deferving of notice: 1. A comparative view of
the value of the different branches of fcience; and 2. The bef
means to render general, not learning, but foundne/s of judgment
and good tafe. »
One of his great objects was to bring the pure mathema-
tics nearer to perfeétion, to amend many faults in them, to
clear up and conne& their different parts, and in particular
to apply them to natural philofophy and aftronomy. Corne-
lius Douwes difcovered an eafy method of determining the
latitude of a place at fea, not by the meridian altitude of the
F4 fun,

72. Biographical Memoirs.

fun, but by two obfervations made at any other period of the,
day. ‘This method, however, being ftill imperfe&, Nieuw-

land turned his thoughts towards the improvement. of it,

_ and in the beginning of the year 1789 wrote a paper on the:

fubje&, which he tranfmitted to M. de Lalande at. Paris,

from whom it met with great approbation. In the year_
1792, when Nieuwland refided two months at Gotha with

Major von Zach, thefe two learned men often converfed on

this method of finding the latitude, and calculated the refult

of cbfervations which they had made with a fextant and an
artificial horizon. The above paper, enlarged by thefe ob-
fervations, was inferted by Major von Zach with Nieuw.
Jand’s name in the firft Supplement to Bode’s Aftronomical
Almanack, Berlin, 1793.

The above, however, was not the only fervice rendered by
this learned man to aftronomy: Newton was the firft philofo-
pher who {poke of the mutual attraétion of the heavenly bo-
dies,and who explained the Jaws of this attration from mathe-
matical principles. D’Alembert, Euler, and Clairaut brought
fill nearer to perfeCtion what Newton had not fufficiently
illuftrated, and defcribed the motion of the moon, the mu-
tual effet which the planets have on each other, the per-
turbations that muft thence be produced in their courfes
and the periods of their revolutions, and alfo the laws to
which thefe perturbations are fubject. There however ftill
remained to be explained fome irregularities in the pheno-
mena of the planets, and that flow variation which takes
place in the inclination of the ecliptic. De la Place alfo
made fome very accurate calculations on this fubje&t. All
thefe great men adopted a truth, which they knew only
from obfervations, that the axes of the planets do not ftand
perpendicular, but inclined to the plane of their orbits. The
axis of the earth, for example, makes with the plane of its
orbit, that is, with the ecliptic, an angle of almoft fixty-fix
degrees and a half, and this inclination alone produces the
feafons ; whereas, it the axis of the earth ftood perpendicular,

we

of the late P. Nieuwland. 73

we fhould continually have the fame feafon, and the days
and the nights. always equal. The caufe, however, of this
inclination. was {till unknown to all the great aftronomers.
Du Sejour fays, in, his analytical treatife on the apparent
motion of the heavenly bodies, that it is highly probable that
this phenomenon depends on fome phyfical caufe; but he
does. not venture to mention it. Nieuwland proceeded far-
ther. He laid down principles from which he drew this
conclufion, that the above phenomenon is intimately con-
nected with the whole fyftem of attraction. On thefe prin-
ciples he made calculations, the refult of which was exa@lly
equal to the angle of the inclination of the earth’s axis to
the plane of its orbit. Nieuwland communicated his difco. _
very with much modefty to the celebrated Profeflor Damen
at Leyden, who propofed fome obje&tions to it which dif=
couraged Niewwland, and induced him to revife his calcula-
tions with more accuracy. Major von Zach tranfmitted the
paper which contained them to M. De la Place at Paris, and
caufed it to be printed alfo, for the opinion of the learned,
in the Supplement to Profeflor Bode’s Aftronomical Alma-
nack for the year 1793.

Nieuwland’s talents and diligence foon recommended hine
to the notice of his country. When in his twenty-fecond
year, he was appointed a member of the commiffion chofen
by the College of Admiralty at Amfterdam for determining
the longitude and improving marine charts. On this labour
he was employed eight years, and undertook alfo to prepare
a nautical almanack, and to calculate the neceflary tables
The mathematical part was in general entrufted to Nieuw-
land; but he aflifted alfo his two colleagues van Swinden and
van Keulen, in the departments affigned to them, with fuch
- afliduity, that moft of the work publithed on the longitude,
together with the three additional parts, were the fruits of
his labour. In the fecond edition of the explanation of the
nautical almanack, he had alfo the principal fhare, and he
was the author, in particular, of the explanation of the equa-

tion

44 . Biographical Memoirs

tion of time, the method of determining the going of a times’
piece, and of calculating the declination of the moon.

Soon after Nieuwland engaged in this employment it ap~
peared as if his deflination was about to be changed. In
the year 1787 he was chofen by the States of Utrecht to fuc=
ceed Profeflor Hennert; but on account of certain circum-
fiances this appointment did not take place. He was how-
ever invited to Amfterdam by the magiftrates of that city,
to give lectures on the mathematics, aftronomy, and naviga-
‘ tion. While in this fituation he wrote his ufeful and excel-
Tent treatife on navigation, the firft part of which was pub-
ifhed at Amfterdam in 1793, by George Hulft van Keulen ;
and it is much to be wifhed that M. van Swinden would
_ complete this work from the papers bequeathed to him by
his deceafed friend the author.

{n aftronomical purfuits, Nieuwland applied not only to
the theoretical but alfo to the pradtical part; and in this
ftudy he was encouraged and affifted by Major von Zach,
with whom he refided fome time in the courfe of the year
7792, after the death of his wife, and who inftru€ted him in >
the proper ufe of the fextant. This affectionate friend pub-
lifhed alfo all his obfervations and calculations in the before-
mentioned Supplement to Bode’s Aftronomical Almanack,

In the year 1789 Nieuwland was chofen member of a
learned fociety whofe object was chemical experiments ; and
fo apt was his geniys for acquiring knowledge, that in a
Kittle time he made himfelf completely mafter of the theory
of chemiftry. A proof of this is the treatife which he read
on the 24th of May 1791, in the fociety diftinguifhed by the
motto of Helix Meritis, and which has been printed in the
firft part of the New General Magazine (Niew Algemeets
Magazyn). At the fame time he was able to examine the
umportant difcovertes made by the fociety, to affift in pre-
paring an account of them for the prefs, and to publith them
with fufficient accuracy in the French language, Three
parts of this work appeared under the title of Recherches

% Phyfico-

of the late P. Niewwland. 7g

Phyfico-chymiques. The firft part appeared in 1792, and was
afterwards re-printed in the Journal de Phyfique. The fecond
was publifhed in 1793, and the fourth in 1794. Some let
ters of his on chemiftry may be found alfo in the Meffenger
(Letterbede).

This ingenious and diligent: man was of great fervice alfo

' in the philofophical department to the above fociety, Felix

Meritis, of which he was chofen a titular member on the
asth of January 1788, and an honorary member on the
15th of March 1791. The papers for which it was indebted
to him are as follows :—1. On the neweft difcoveries in aftro-
nomy, and the progre/s lately made in that fcience, 1788. This
is an extract from a Latin oration which he intended to have
delivered at Utrecht when he expected to fucceed Profeffor
Hennert.—2. On the figure of the earth, 1789.—3. On the
courfe of comets, and the uncertainty of the return of the
comet now expected, 1790.—4. On the nature of the mathe-
matics. The principal objeé& of this paper was to illuf-
trate the idea, that the mathematics may be confidered as a
beautiful and perfect language.—s. On the periodical decreafe
or increafe in the light of certain fixed flars, and particularly of
the fiar Algol, 1790.—6. On the folution of fpherical trigono-
metry by means of a new inftrument invented by Le Guin, 1 791s
M. le Guin having tranfmitted to the College of Admiralty
at Amfterdam an inftrument which might be ufed with great
advantage i in trigonometrical operations, and by which, in
calculating the longitude, one could deduce the real from-
the apparent diftance, the Admiralty charged Nieuwland to
examine this inftrument; and he found that it might be of
excellent fervice for the above purpofe.—7. On the relative
walue or importance of the fciences, 1791.—8. On the Syftem of
Lavoifier, 1792.—9. On the Selenotopographia of Schroder,
1793:-—10. On what is commonly called cultivation, infirucion,

or enlightening, 1793.
Nieuwland had applied clofely to the mathematics, aftro-
nomy and navigation for fix years, during which time he
made

~6 Biographical Memoirs of the late P..Nieuwland.

made confiderable improvements in nautical charts, and
filled up his. vacant hours withthe ftudy of philofophy and
chemiftry. In the month of July 1793 he was invited to
the univerfity of Leyden, to be Profeffor of Philofophy,
Aftronomy, and the Higher Mathematics, in the toom of
‘the celebrated Damen; and the Admiralty of Amfterdam
requefted him to continue his nautical refearches, which he
did with great affiduity till the period of his death. The
only variation which he now made in his ftudies related to
natural philofophy, for with the mathematics he was already
fufficiently acquainted. He applied therefore to the experi-
mental part, and {pared no pains nor labour to become perfec
in it; which would certainly have been the cafe, had he not
been {natched from fcience and his friends at the early age
of thirty. He died of an inflammation in his throat, accom=
panied with a fever, on the 13th of November 1794.

In his external appearance, Nicuwland was not what might
be called .handfome, nor had he ever paid much attention to
acquire that eafe of deportment which diftinguifhes thofe
who have frequented polite company. His behaviour and
“converfation were however agreeable, becaufe he could dif-
courfe with facility on fo many. fubje€ts, and never withed
to appear but under his real character. On the firft view
one might have difcerned that he was a man of great mo-
defty and the ftriéteft morality. His father wasa Lutheran,
and his mother a baptift ; but he himfelf was .a member of
~ the reformed church, and always fhewed the utmoft refpe&
for the Supreme Being both by his words and his a@tions.

XVII. De-

XVII. Defcription of M. Des VicNnES’s improved Apparatus
for faturating Water, Solutions of Mineral and Vegetable
‘ Alkali, Esc. &s°c. with Carbonic Gas 3 or for making artificial
. _ Mineral Waters... Communicated by the Inventor.

[With a Plate, No. IV.)

A FIG. 1. a bottle or veffel in which marble, chalk, or
any An proper fubftance, is to be put with a little water.
B a bottle containing fulphuric acid, and having its neck
ground to fit in the firft bottle at C, and a cock a by which
any quantity of the acid can be introduced to the chalk or
other fubftance. As the gas is extricated, it pafies through
the tube D into the veffel E, which contains the liquid to be
faturated : the gas by its elafticity prefles the liquor, and
forces it through the tube F into G. At H is a {mall hol-
low glafs ball I with.a ftem ground to fit the mouth of the
veflel G, which it fhuts'as.a valve by the preffure of the.li-
quor, afhfted with a fpiral fpring, until the water or other
liquid, which has been forced through the tube F into G;
preffes down by its weight the ball I, and returns back into
E. When it accumulates to a certain point in E, the valve
is again fhut, and it rifes through the tube F as before.

At 4 is a {topper to which hangs a fmall weight, about
half an ounce, which aéts as a fafety valve to prevent the
preffure from reaching that point which would endanger the
burfting of the veffels.

The advantage which this apparatus poffeffes, is, that it not

‘only gives the fame preffure of the gas upon the furface of
the liquor to be impregnated, which the common machines
do, but, by the conftant agitation which is kept up, by the
afeent and defcent of the fluid, continually expofes a frefh
furface of it to its ation: by which means water or other
liquors may,be as fully faturated in two hours as they can in
twelve, by any apparatus in common ufe.

Brie. 2 is a fe€tion of the valve ball I, the fpiral {pring K,

. and

rk On anew Metal called Tellurium.

and the cork L, to which the two former are faftened- Af
c is a piece of lead, which ferves at the fame time to adjuft
the weight of the ball, and to keep it in an upright pofition.

Fig. 3 isa plan of the cork, fhewing the apertures through
which the liquor defcends. The tubes D and F are each in
two parts, joined by pieces of elaftic gum, by which means
the apparatus admits of being moved without danger of
breaking. There is alfo a glafs rod e in the veflel A for the
purpofe of ftirring the materials. This rod paffes tight
through a piece of gum elaftic (the mouth end of one of the
common bottles made of that fubftance), the other end of
which is fitted clofe to the mouth of the veffel A, by means
of wire or catgut wound round it, to prevent the efcape of
the gas.

RVIM. Extract from a Memoir by Piofifor KLAPROTH, on
anew Metal called Tellurium, recd in a public Sitting of the
Academy of Sciences at Berlin, Fan. 25th, 1798.

Proressor Klaproth, on fubje@ting to a chemical analy~
fis the ore of the auriferous mine known under the denomi-
nation of the mine of white gold, aurum paradoxum, metal-
Lum vel aurum problematicum*, found in that mineral a metal
abfolutely different from any hitherto known, and to which
he gave the name of ¢el/urium, as a companion to the urani-
um and titanium, new metals difcovered fome time ago by
the fame chemift.. M. Muller of Reichenftein had, fo early
as 1782, fufpected that this ore contained a peculiar metallic
fubftance, and his fufpicion was confirmed by Bergman, to —
whom he had fent fome of the ore ; but on account of the q
{mall quantity with which he had made his experiments he
wauld not venture to decide, where it contained a new

* This ore is found in the mine called Maviabilf in the Fatzbay moun-
tains near Zalethna in Tranfylvania. See Emmerling Elemens dé Mine- —
rploziey t. xi, p. V2.4.

‘On a new Metal called Tellurium. 79

metal, or whether what had been taken for a particular kind
of metal might not be only antimony. The repeated and
ingenious experiments made by M. Klaproth on a more con-
fiderable quantity of the ore, which had been tranfmitted to
him by M. de Reichenftein, fully confirmed the conjectures
of the latter as well as thofe of Bergman.

Procefs for obtaining the Afetal from the Ore.

1. The ore is gently heated with fix parts of the muriatic
acid ; three parts of the nitric acid being then added, the
mixture is boiled ; upon which there arifes a very confiderable
effervefcence, and a complete folution is obtained.

2. The filtered folution is diluted with as much water as
it can bear without becoming turbid, which is a very {mall
quantity, and a folution of cauftic potafh is then added to
the liquor, until the white precipitate which is at firft formed
difappears again, and nothing remains but a brown flaky
fediment. ‘
3. This laft precipitate is the oxyde of gold mixed with the
oxyde of iron, and a feparation is effeted by the common

. means.

4. The muriatic acid is added to the alkaline folution (2)
in fufficient quantity to faturate the alkali entirely: an ex-
eefs of the acid muft be avoided. A white precipitate,
which, by heat, fettles at the bottom of the veffel under the
form of a heavy powder, is produced in great abundance.
After the precipitate has been wafhed and dried, it is formed
into a kind of pafte with a fufficient.quantity of any fat oil ;
and this mafs is put into a fmall glafs retort, to which a re-
cipient is flightly fitted. When this arrangement is made,
it is gradually brought toa red heat ; and in proportion as the
oil is decompofed, there are obferved, as in the diftillation of
mercury, brilliant and metallic drops which cover the upper
part of the retort, and which, at intervals, fall to the bottom
of the veffcl, and are immediately replaced by others. Aiter
it has cooled, metallic fixed drops are found adhering to the
fides of the retort and at the bottom of ‘the veffel, and the

remainder

80 On anew Metal called Tellurium.

- remainder of the metal reduced and melted with @ ne
furface, and almoft always cryftallized.

Effential chubstierilig Marks of this new Metal.

1. It has the white colour of tin, approaching to the grey
colour of lead. Its metallic fplendour is confiderable, and
its fra@.ure laminated. It is highly brittle and friable. By
fuffering it to cool quietly and gradually, it readily aflumes.2
cryftallifed furface.

2. Its fpecific gravity is 6.115.

3. It belongs to the clafs of the moft fufible metals.

4. When heated by the blow-pipe upon charcoal, it burns
with a very lively flame of a blue colour, inclining at the
edges to green. It is fo volatile as to rife entirely in a whitifh
grey {moke, and exhales a difagreeable odour like that of
radifhes. On ceafing to heat it, without having entirely -
volatilifed the fmal! portion fubjeéted to this operation, the
button which remained, retained for a long time its Jiquidity,
and, by cooling, was covered with a radiated vegetation.

5. ‘This metal amalgamates eafily with mercury.

6. With fulphur it forms a grey fulphure of a radiated
ftructure.

7- A folution of it in the nitric acid is tranfparent and
colourle’s. When concentrated, it produces, in time, {mall
white light cryitals, in the form of necdles, which exhibit a
dendritic aggregation.

8. The new metal diffolves in the nitro-muriatic acid.
When-a large quantity of water is added to fuch a faturated
folution, the metal is precipitated in the ftate of an oxyde,
under the form of a white powder, which, in this ftate, is
foluble in the muriatic acid.

g- By mixing cold, in a well-ftopped veffel, a fmall quan-
tity of this metal with a hundred times its weight of cons
centrated fulphuric acid, the latter gradually aflumes a beau-
tiful crimfon red colour. By means of a {mall quantity of
water added, drop by drop, the colour difappears, and the

fmail,

On a new Metal called Tellurium. Sx”

{mall quantity of the metal diffolved, depofits itfelf under
the form of black flakes; Heat deftroys the folution : it
makes the red colour difappear, and difpofes the metal to fe-
parate in the ftate of a white oxyde.

10. When, on the other hand, the concentrated fulphuric
acid is diluted with two or three parts of water, and’a fmall
quantity of the nitric acid has been added, a confiderable
quantity of the metal will then be diffolved. The folution
is tranfparent and colourlefs, and is not decompofed by the
mixture of a larger quantity of water.

11. All the pure alkalis precipitate from acid folutions of
this metal an oxyde, of a white colour, foluble in all acids :
by an excefs of alkali, the precipitate which is formed is en-
tirely re-diffolved. If carbonate be employed inftead of pure
alkali, the fame phenomenon takes place—with. this differ-
ence, however, that, by excefs of the latter, the precipitate
formed is re-diflolved only in part.

12. Exceedingly pure pruffiate of potafh produces no
precipitate in folutions of this metal. ;

13. Alkaline fulphures mixed with acid folutions occa-
fion a brown or blackifh precipitate, according as the metal
is combined with more or lefs oxygen. It fometimes hap-
pens that the colour of the precipitate has a perfect refem-
blance to mineral kermes, or red {ulphurated oxyde of an~
timony.

When the fulphure of tellurium is expofed on burning
charcoal, the metal burns with a blue colour conjointly with
the fulphur.

14. The infufion of gall-nuts, combined with the fame
folutions, gives birth to a flaky precipitate of an Ifabella
colour.

15. Tron and zine precipitate tellurium from its acid fo-
lutions in a metallic ftate, under the form of fmall black
flakes, which refume their fplendour by fri&tion, and which,
on burning charcoal, melt into a metallic button.
ee en G 16, Tin

82 On a new Metal called Tellurium

16. Tim and antimony produce the fame phenonienoit
with the acid folutions of the new metal.

The precipitate formed by the antimony proves, in a ftrik-
ing manner, that tellurium is not a difguifed antimony, as
has been fuppofed. A folution of tin in the muriatie acid,
mixed with a folution of tellurium in the fame acid, pro~
duced alfoa black and metallic precipitate.

17. The oxyde of tellurium, obtained from acd. folu- ,
tions by alkalis, or from alkaline folutions by acids, are both
reduced with a rapidity refembling detonation, when they
are expofed to heat on charcoal. It burns, and is volatilifed, ~
as has been already mentioned.

18. By heating for fome time this oxyde of tellurrum in
a retort, it melts, and appears, after cooling, with a yellow
ftraw colour, having acquired a fort of radiated textare,

1g. Mixed with fat bodies, the oxyde of tellurium is.
perfeCtly reduced by the method above pointed out.

The ore of white gold of Fatzebay, aurum vel metallum
problematicum, contains: tellariumt 925.5, iron 72.0, gold
2.5: total 1000.0.

The graphic gold of Offenbanya contains: tellurium 60,
gold 30, filverio: total 100-0.

Ore from the mine known under the name of the yellow
mine of Nagyag contains: tellurium 45, gold 27, lead 19.5,
filver 8.5, fulphur one atom : total 100.0,

Ore from the mine known by the name of the mine
of grey foliated gold of Nagyag contains: lead 50, tel-
lurium 33, gold 8.5, fulphur 7.5, filver and copper 1: total
400.0.

[83]
MIX. Some curious Circumflances refpeEting the two Ele-

phants brought to Paris from the Hague. From a late
French Journal.

Tue place for their reception had been long prepared.
Itis a fpacious hall in the Mufeum of Natural Hiftory, well
aired and lighted. A ftove is placed in it to warm it during
the winter, arid it is divided into two apartments, which
have a comniunication with each other by means of a large
door refembling a portcullis. The enclofure round thefe
_ apartments confifts of rails made of {trong thick beams, and
a fecond enclofure, breaft-high, runs round them, to keep
the fpeCtators at fome diftance, and preferve them from ac-
cidents.

The morning after their arrival thefe animals were put

in poffeflion of their new habitation. The firft conduéted
to it was the male, who iffued from his cage with precau-
tion, and feemed to enter his apartment with a degree of
fufpicion. His firft care was to reconnoitre the place. He
examined each bar with his trunk, and tried their folidity
by fhaking them. Care had been taken to place on the out-
» fide the large fcrews by which they are held together. Thefe
he fought out, and, having found them, tried to turn them,
but was not able. When he arrived at the portcullis, which
feparates the two apartments, he ebferved that it was fixed
only by an iron bar, which rofe in a perpendicular direction,
He raifed it with his trunk, pufhed up the door, and entered
into the fecond apartment, where he received his breakfaft.
He ate it quietly, and appeared to be perfeétly eafy.

During this time people were endeavouring to make the
female enter. We {till recolle& the mutual attachment of
thefe two animals, and with what difficulty they were parted,
and induced to travel feparately. From the time of their de-
parture they had not feen each other; not even at Cambray,
where they paffed the winter. They had only been fenfible
that they were near neighbours. The male never lay down,

Ga > bug

84 On the Elephants brought to Paris.

but always flood upright or leaned againft the bars of his
cage, and kept watch for his female, who lay down and flept
every night. On the leaft noife, or the {malleft alarm, he
fent forth a cry to give notice to his companion.

The joy which they experienced on feeing each other after
fo long a feparation may be readily imagined.

When the female entered, fhe fent forth a cry expreffive
only of the pleaftre which fhe felt on finding herfelf at li-
berty. She did not at firft obferve the male, who was buly
feeding in the fecond apartment. The latter alfo did not im-
mediately difcover that his companion was fo near him; but
the keeper haying called him, he turned round, and imme-
diately the two animals rufhed towards each other, and fent
forth cries of joy fo animated and loud, that they fhook the
whole hall. They breathed alfo through their trunks with
fuch violence, that the blaft refembled an impetuous guft of
wind. The joy of the female was the moft lively: fhe ex-
preffed it, by quickly flapping her ears, which fhe made to
mye with aftonifhing velocity, and drew her trunk over the
body of the male with the utmoft tendernefs. She, in parti-
cular, applied it to his ear, where fhe kept it a long time, and,
after having drawn it oyer the whole body of the male,
would often move it affectionately towards her own mouth.
The male did the fame thing over the body of the female,
but his joy was more concentrated. He feemed to exprefs
it by his tears, which fell from his eyes in abundance.

Since that moment they have never been feparated, and
they occupy together the fame apartment. The fociety of
thefe two animals, their habits, their mutual tendernefs, and
their natural attachment, full excited by the privation of
liberty, will furnifh curious obfervations for the hiftory of
their f{pecies.

Thefe two elephants, which are natives of Ceylon, were
brought to Holland when very young. They are about
fifteen years of age. Their height is feven feet and fome
inches. Their tufks, which are very fhort, have been

broken,

“as

Dutch Embaffy to China. 85
broken, but they will grow up again as they become older.
The tail of the male hangs down to the ground: that of the
female is much {horter.

XX. Some Particulars re[peéting the late Embaffy of the
Dutch Eaft India Company to the Court of Pekin.

Crrzen M. L. E. Moreau de Saint Mery has lately
publithed, at Paris, an extract from Van Braam’s Journal of
the Embafly of the Dutch Eaft India Company to the Em+
peror of China, in the years 1794 and 1795, one volume
quarto, being the firft, The fecond, accompanied with maps
and engravings, is announced as about to appear.

The principal objeé of thofe who give an account of their

travels to the public, ought to be to make known the ufages,

public and private manners, the legiflation, arts, induftry,

productions, the temperature, commerce, religion, and go-

vernment of thofe countries which they traverfe.

Thofe of Citizen Van Braam have not been written accord-
ing to this fyftem ; nor indeed could they, for the members
of the embafly were hardly fuffered to have any kind of in-
tereourfe with the natives. His work, as the title announces,
is only a journal, containing an account of the different places
through which the author paffed in going from Canton to
Pan. and returning by the fame route.

If this Journal, which feems to have been written cat for
the private fatisfaction of the author, does not give an exten-
five and profound knowledge of China, it contains, at any -
rate, feveral details which may be ufeful to thofe who with
to colleét information refpecting this fingular and interefting
country. /

There are three ways of travelling in China. By water, in
veffels called yachts; by land, in palankins carried by men
called coulis, or in {mall carriages made like wheel-barrows.
The eftablithment of pofting, and fulpended carriages, ave

G 3 unknowy

86 . Dutch Embaffy to China.

unknown in that country. The horfe, the mot beautiful
end ufeful animal in Europe, is defpifed there. Buffaloes,
mules, and dromedaries, are the animals principally employed
for tranfportation.

In no country does agriculture flourith fo much as in China,
This art is there beheld with almoft religious veneration.
On this fubje& there are treatifes, brought to perfeétion by
application and the experience of feveral ages : thefe treatifes,
faited to the foil of each canton, are depofited in the hands
of the mandarin who aéts as firft magiftrate ; and he takes
care that the neighbouring farmers fhall be made acquainted
with, and turn to advantage, the leffons which thefe treatifes,
contain.

Citizen van Braam {peaks of the monuments which he
frequently met with on his route, and which he chara¢terifes
under the name of triumphal arches, and o¢tagonal or hexa-
gonal towers confifting of feven or eight ftories, He does
not explain the ufe of thefe towers, which appear to be in
China what obelifks were among the Egyptians.

With regard to the triumphal arches, Citizen van Braam
fays that they are monuments erected to the memory of
warriors who rendered feryices to their country, and fome-
times to private citizens who fignalifed themfelves by their
virtues. Some have been ereéted alfo to young women and
wives: to the former on account of their chaftity, and to the
latter on account of their fidelity.

If perpetual virginity could be made to a¢cord with nature,
it would be no great merit in China to devote one’s felf to.
it; for the manner in which women are there treated, is not
much calculated to awaken in young perfons of that fex a
defire of being chafte. Parents carry on a kind of trafhe
with their children. Thofe who are faid to be of good birth
give them in exchange for a large dowry, which they put
into their own pockets: others fell them like merchandife,
without caring what becomes of them. The wives of the
ich live in perpetual confinement; thofe of the feeond

i order

Duich Embaffy to China. 8;

erder are the fervants of their hufbands; and thofe of the
lower clafs of the people are forced to take a thare in the
fevere labour of the men, who treat them as we treat thofe
animals which affift us.

The emperor is revered as a god. The power of the
fovereion and of a high-prieft are both united in his perfon.
The fame homage is paid to the edicts which he iffues, the
difpatches which he figns, and the prefents which come
from him, as are paid to himfelf. That is to fay, the people
proftrate themfelves before a piece of paper, or filk, as they
do when they are in his prefence. The embaffadors were

feveral times obliged to make ridiculous falutations before
the remains of bad provifions, or paftry, which the emperor
had fent them from his table as a mark of particular con-
fideration and favour.

The court of Pekin prefents-nothing firiking. The moft
remarkable object is the wall by which it is furrounded. All
the apartments are narrow and mean, and confufion prevails
in all the ceremonies, which are conduéted without any
order whatever.

The entertainments to which the embaffadors were invited,
confifted of a few breakfafts where the emperor was prefent.
Some boiled meat, confeétions, paftry, a beverage called
famfon, and another called bean-milk, ferved up on tables
around which the guefts fquatted down upon cufhions,
formed the chief articles at thefe morning collations.

It appears that the people of China make very bad cheer.
The want of the pleafures of the table is not fupplied by
others. The Chinefe fpectacles confift only of a few feats
of tumbling, and extemporary farces. And thefe fpetacles
even are not public. They are exhibited only in the interior
part of the palace, and in the houfes of fome of the chief
mandarins.

In this country there is no focial communication among
the inhabitants, who live infulated and confined to their
own homes,

G4 Though

83 Duich Embaffy to China.

Though the embaffadors remained more than a month
at Pekin, Citizen van Braam fays nothing of the manners,
commerce, or monuments of that city. This will not appear
aftonifhing, when it is known that the members of the em-
bafly, like thofe which preceded them from England, were
confined to their hotel, as if they had been in prifon;
‘that they were narrowly watched; that the letters which
‘they fent to fome miffionaries of their acquaintance were
infpected at the poft-office ; and that they never went out
in order to go to court, at three or four o’clock in the morn-
ing in the middle of winter, without being efcorted by con-
duétors. Such is the jealoufy which the Chinefe entertain |
of Europeans of every defcription, ever fince a former
emperor, expreffing his furprife to a Spanifh jefuit, who
had lefs cunning than his affociates, at the immenfe power
and territory which the king of Spain had acquired in
South America, was informed by the latter, that, having
once gained an eftablifhment in the country, miffionaries
were fent among the people to convert them to the Roman
Catholic faith, after which their /ubjugation followed as a
matter of courfe !

The people to whom Confucius preached his fimple and
fublime morality, the people who ereéted temples to that ©
philofopher, ought to be rational in their worfhip: but they
are vilified and degraded by the moft abfurd idolatry; their
pagods are filled with idols of the moft monftrous and
whimfical figures.

If the Chinefe, however, are idolaters, they are not into-
lerant; for Citizen van Braam fpeaks of a’ Chriftian to

whom they haye erected temples, and whom they ftyle a
faint. |

Purass') ‘3 XXI. Chemj-

[ 89 J

XXT. Chemical Experiments refpecling different Methods of

~ rendering Paper and the Writing on it inde/truétible by Fire.
By Mr. L. Brucnaretii. From Crell’s Chemical
Annals for 1797.

O; all the fubftances I have tried, liquor of flint is that
which, after a feries of experiments, appears to me to be the
moft incombuftible, and the moft proper to fecure paper
from deftruction by fire. I dipped the fheet of paper feveral
times in the above liquor, frefh made, or, I daubed it feveral
times over the whole paper with a hair brufh, and dried it m
the fun or in an oven. Paper prepared in this manner loft
fome of its foftnefs, became a little rougher than before, and
acquired a lixivious cauftic tafte. In other refpeéts it was
not different from common white paper. When this paper
was laid upon glowing coals, it did not burn like common
paper, but became red, and was converted to a coal, which
however did not fall.into afhes like the coal of common
paper, fo that it might therefore be confidered as petrified
paper. This coal, however, is exceedingly friable; for,
when it is taken between the fingers, or prefled together in
any manner whatever, it drops to pieces.

As the chemifts confider incombuftibility as one of the
principal chara¢teriftics of faline fubftances, I made experi-
ments with different kinds of falts, to try whether they
would render paper incombuftible, like this liquid filiceous
potafh, which is not a falt, but a combination confifting of
two fubftances.

I took feveral fheets of common white writing-paper, and
dipped each of them, in the fame manner as I had proceeded
with the above liquor of flint, in a particular falt, and ob-
ferved how the different leaves withftood the fire when
thrown into it. I fhall here give an account of my obferva-
tions as they occurred.

No. I. Paper dipped in nitrite of lime.—Leaves of paper
which had been foaked in nitrite of lime diftinguifhed them- -

3 felves

9° On rendering Paper indefirudtible by Fire.

felves.neither in whitenefs nor fmoothnefs from common,
paper. They burnt very readily, and were reduced much
fooner to afhes than comman paper.

‘No. IT. Paper dipped in nitrite of magnefia.—Paper dipped
in this falt appeared in nothing different from common
paper, It burnt as foon as it was brought near a flame,
and was converted to a very black coal, which however was
not fo friable as the firft mentioned,

No. Ill. Paper dipped in nitrite of ammoniac.—Leaves of
paper foaked in nitrite of ammoniac became again moift,
after they had been weil dried by the heat of the fun. They
burnt in the fire and produced a very friable coal, which wag
afterwards entirely deftroyed by the flame.

No. IV. Paper dipped in muriate of lime.—Leaves of
‘paper which were dipped in this falt after it had been dif-
Solved did not appear different, when dried, from other leaves
not prepared in the fame manner. When put in the flame
they burnt very readily, and almoft in the fame manner as
commen paper, and were converted into a fomewhat white,
but highly friable coal,

No. V. Paper dipped in muriate of barytes.—Paper dipperk
in this falt did not feem changed in any of its external pro-
perties. It burnt when placed over the fire, and produced a,
very black fhining coal, which was however fomewhat lefs

-friable than the two laft mentioned.

No. VI. Pager dipped in muriate of foda.—Paper dipped
in muriate of foda acquired more confiftence and became
rough. It burnt in a flame, and the refidue was a very black
denfe and fhining coal, not more friable than the foregoing,

No.VII. Paper dipped in muriate of potafb.—W ith nruriate
pf. potafh the paper became fomewhat rough, but in other.
refpects no alteration was obferved. Ii burt without flam-
ing, and was conyerted into a very black and fnable coal.

No. VU. Paper dipped in muriate of ammoniac.—Paper

- dipped in this falt underwent no vifible change. When put
into the fire, it burnt and was converted to a black coal; but
when

On rendering Paper indefirudible by Fire. or

when continued in the fire it became reduced to afhes like
common paper, on account of the muriate which was de-
ftroyed by the heat. This paper, then, is in nothing different
from common paper.

No. 1X. Paper dipped in fulphite of magnefia.— Paper dip-
ped in fulphite of magnefia acquired more confiftence and
more toughnefs than it had before. When held ina flame it
took fire, and was converted into a friable coal of an afh grey
colour ; when it was however held longer in the fire, it was
converted into fome grains of a very white colour, which, by
the chemical teft, I difcovered to be fulphure of magnefia.

No. X. Paper dipped in fulphite of alumine,—Paper dip-
ped in diffolved fulphite of alumine, in which it was kept
fome time before it was dried, fuffered no vifible change, ex-
cept that it was a little harder. When burnt, there re-
mained a very black coal, which was more friable than that
obtained from paper dipped in liquor of flints.

No. XI. Paper dipped in [ulphite of foda.—Paper dipped
qn fulphite of foda fhewed no vifible change. On the fire it
was converted into a very bright coal, which was deftroyed
by the flame of a candle. It became glowing, puffed itfelf
up, and was totally changed into fulphure of foda, which
with fome acids had the fmell of rotten eggs.

No. XII. Paper dipped in fulphite of potafb.—Some leaves
“of paper which had been dipped in diffolyed fulphite of pot-
afh, imbibed this falt exceedingly well; but it afterwards
burnt in the fire, and was converted to a black coal, which
foon after glowed, and was then totally deftroy ed. It how-
ever afterw ards collected itfelf in fmall particles of se sttan
of potafh.

No. XIII. Paper dipped in fulphite of ammoniac.—Paper
dipped in this falt affumed, after being dried in the fun, the
moiftnefs of the atmofphere. When burnt, the refiduum

was a black fhining friable coal, which became afterwards
annthilated like the former.

No. XIV.

62 _ Account of a new Wood for Dyeing.

No. XIV. Paper dipped in the acetite of magnefia.— Paper
dipped in this falt did not appear to be in the leaft changed,
It burnt with a weak white flame like common paper, and
was converted into a very friable afh-coloured coal.

No. XV. Paper dipped in acetite of barytes.—Paper dipped
in this falt feemed, like the former, to have undergone no
vifible change. It burnt with a white flame, as common
paper, and was at laft changed into a coal of the like kind.

From the above obfervations it appears, that white falts
do not deprive paper of its combuftiblenefs like the liquor of
flint. Some of them alfo, inftead of defending it from the
action of the fire, tend rather to accelerate its deftruction,
as, for example, the fulphites. The fulphureous acid which
they contain lofes with the inflammable body its oxygen, is
converted into fulphur, and produces a little liver of fulphur,
which is deftroyed at the fame time with the paper by the

flames.
[To be concluded in the next Number.|

XXII. Report made to the Council of the Mines in Spain re-
SpeGiing anew Wood proper for Dyeing, called Paraguatan.
By D. Dominic Garcia FernanDdEz, Infpector of the
Mint. From the Annales de Chimie.

In compliance with the orders of the Supreme Council of
Commerce and the Mines, I undertook a chemical examina-
tion of a wood known in Guiana under the name of Para-
guatan. This examination I carried to fuch a length as I
thought neceffary for acquiring a knowledge of its nature,
and of the advantages that may be derived from it in dyeing,
I obferved in the firft place that the bark, the wood properly
fo called, and the leaves, of the paraguatan produce different
colours. The leaves, however, do not merit much attention,
as they communicate only a fading and not very agreeable
colour. My refearches have, therefore, been directed chiefly
to the bark, as that part is the moft important, and my obfer-

se yations

Aécount of a new Wood for Dyeing. 93
vations refpeéting the bark may be applied alfo to the wood ;
for, though the latter produces a different colour, it exhibits
almoft the fame phenomena as the bark.

If the bark be boiled in water, the coloured extra& thence
refulting, when expofed to the action of the fulphuric, muri-
atic and nitric acids, refifts them much longer than an ex-
tract of brafil or lozwood. The colour, after being deftroye
by a combination of acids, may be revived by the means of
alkalis.

Vinegar, Jemon-juice, and tartar render this dye more
brilliant, and communicate to it a fine rofe colour, while
thefe acids, on the other hand, deftroy the colour of brafil
and logwood altogether.

The fecule of the bark of the paraguatan attach them-
felves and adhere to woollen, cotton, and filk. The colour
is more brilliant on filk than woollen, and more brilliant on
the Jatter than on cotton.

The fame fecule dried may be afterwards diffolved in
alcohol, and communicate to it a tint fimilar to that obtained
from cochineal.

By mixing alum with a highly concentrated deco&ion of
the fame fubftance a fpecies of lake may be produced, but
neither fo lively nor fo pretty as that obtained from cochi-
neal by a like procefs.

_ The fame deco¢tion mixed with that of gall-nuts furnifh-
ed me with a precipitated pigment of a weak rofe-colour. An
infufion of brafil or logwood, mixed with an infufion of
galls, affumes a darker and browner tint; mine on the other
hand became clearer by it, and affumed a delicate rofe colour,
or,one fomewhat fimilar.

It muft indeed be acknowledged, that the dye extracted
from the paraguatan has not a ftrength equal to that of co-
chineal. It is however fuperior to thofe of madder, brafil
and logwood, fince it refifts vinegar, lemon-juice and tartar,
Soap even does not deftroy it fo fpeedily as it does thofe of
brafil and logwood.

The bark is attended with this adyantage, that by employing

it

6
64. Account of a new Wood for Dyeing.
it in certain quantities, and giving’ a fuitable preparation to fill;
we by thefe: means may produce the various thades of rofe and
poppy colour, which can be produced only by the carthamus
or fafflower with alkaline mixtures, afler a difficult procefs;
tedious wafhings, and other embarrafling miariipuldtions.

By examining the external form of a piece of the paragua-
tan, it appears to me to be the fame tree as that which Francis
Correal fays he obferved in the province of Popayan*, whiclt
is not far from Guiana. The fame author relates that this
tree is different from that of Brazil; that the trunk, whicli
is the fize of one’s thigh, is thirty or forty féct-in height;
that its bal is full of longitudinal grooves; that the wood
when ftrippéd of its bark is of a bea obit red; and that the.
Indians employ the wood mixed with a red earth to dye the
cotton which they ufe for dreffes.

The colour extracted from the paraguatan does not refit the
action of light: no colour indced can ftand that teft. This
colour, however, will ftand much longer than that of bra-
fil-or logwood ; but, on the other hand, thefe two trees fur-
nifh colouring matter in greater abundance.

I confider the paraguatan, therefore, as oné of thofe walu-
able productions which America ftirnithes to Spain. Tt may
be employed with advantage im the art of dyeing throughout
all Europe. It is to be wifhed that fearch may be made:
for it in Popayan, and that fome of the earth mentioned by
Correal may be fent over to us. The governor of Guiana
ought alfo' to colle& every information poffible that may re-=
late to the paraguatan, and to tramfmit it to us, as well as
other fpecimens of the wood, with fome of its leaves aid
flowers, in order that its fpecies may be determined.

A knowledge of this wood begins to be extended, as I
lately received a portion of its bark and of a red fubftance;
which were brought from Guiana by an Englifhman named
Milnes. It is to be prefumed that this fubftance is the fame
as that mentioned by Correal in his voyages.

* Voyages aux Indes Occidentales, +722; ps 420s

INTEL-

F of

INTELLIGENCE.

LEARNED SOCIETIES.
FRANCE,

Prizes propofed by the National Inflitute, in the Sitting of
Germinal 15, (April ath, 1798:)

FIRST PRIZE.

Vant OUS artifts have already prefented » feveral:
models and machines, deftined for giving -afliftance to the
higheft ftories of houfes in cafes of fire; but the Inftitute
wifhing to negleét nothing in an object of fo much import-
ance to humanity, has confidered it as a duty to make it the
fubje& of a prize.
It invites therefore ingenious men and artifts to prefent
either models or defcriptions of machines, or to point out
any means which may be ufed for giving affiftance to every
ftory of a houfe on fire. Thefe means muft be of fuch ax
nature, that they can be tranfported with facility to different
quarters of a city or town; that they can be fpeedily ere€ted
before the houfe to which affiftance is to be given, and that
women and children may be able to defcend by them from
the higheft fiories without any danger. It is defired that
thefe means may be.as little impediment as poffible to fire-
engines, and to the manceuvres deftined to check the progrefs:
of the flames. The competitors are requefted to procure
information refpecting the practices followed at prefent, in.
different towns, in the like cafes. They are requefted alfo
not to negleé to point out particular means which, though;
not generally ufed, may be employed in many cafes ;. but.
thefe means mutt be fimple, and ealy to be put in practice.
* The prize will be a kilogtamme of gold.
The compctition will take place on the 15th of Nivofe,
the 7th year (January 4th, 1799), and the Inftitute will pro-
: claim

96 _ French National Inflitute.

claim in the public fitting of Germinal (beginning of April)
following, the piece w Wick fhall have gained the prize.

Second Prize. To determine by a great number of ob-
fervations, the beft and the moit medern which can be pro-
eured, the epochs of the longitude of the apogeum or node
of the moon.

Thefe obfervations muft be at leaft five hundred in
number.

The prize is a gold medal of the value of a kilogramme.
The learned of all nations are invited to this competitiony
and they may write in any language whatever. —

_ The works will not be received till the laft day of Frimaire,
Sth year, (December 21, 1799.)

The Inftitute will proclaim the -piece which fhall have
gained the prize, in its public fitting of the 15th of Germi-
nal following (April 4th, 1800).

Third Prize. To point out the earthy fabless and
proceffes proper for manufacturing earthen ware, capable of
ftanding fudden tranfitions from heat to cold, and fo cheap
as to be within the reach of every clafs of citizens.

This art is fill far from being carried to that degree of
improvement fo defirable for the public benefit, while fome
neighbouring nations who do not make porcelain, manufac-
ture earthen-ware exceedingly ufeful, and fuperior to that
made in France. The Inftitute requefts the competitors to
examine the compofition of the beft earthen-ware; the quality
of thofe natural earths which may ferve to form it, or that of
the artificial mixtures which might be fubftituted for it; the
manner in which thefe earths ought to be managed in order
to give them the neceffary properties; the art of baking;
the degree of heat; the form of the requifite furnaces ; and,
above all, the proceffes proper for colouring and glazing
without the oxydes of pernicious metals.

The competitors will remit to the Inftitute famples of the
earths employed in their potteries, and the earthen-wares
themfelves which have been manufaGtured in them..
ie a Thefe

French National Infituse. 07

’ "Phefeé faniples of earth and pottery will be received till
the firft day of Meflidor, the year 7 (June 185 1799).
’ The Inftitute in its fitting of Vendemiaire 5th (Sept. 27)
will proclaim the piece which fhall have gained the prize:
' Fourth Prize. To difcover by accurate experiments what
is the influence of the atmofpheric air, light, water, and ;
earth, on vegetation. | |

The prize is a gold medal of the value of a kilogramme.
‘The works will not be received till the laft day of Frimaire
the 8th year (December 21, 1799), atid the Inftitute will
proclaim the piece which has gained the prize in its public
fitting of Germinal 15, (April 4; 1800).

Clafs of the Moral end Political Sciences.
__ This clafs has. propofed for the fubjet of the prize of the
. 6th year, the following queftion:

To determine the influence of figns on the formation of
ideas. .

The pieces received on this fubject not having anfwered
the conditions of the queftion, though feveral of them con-
tained -interefting refearches, the clafs propofes again the
fame fubje& for the 7th year, and invites to the competition
thofe, above all, whofe firft efforts have merited its attention.

The prize will be 5 hectogrammes of gold ftruck into a
medal. It will be delivered out in the public fitting of the
15th of Nivofe, the gth year (January 4, 1801).

The works will not be received until the 15th Nivofe of
the 7th year (January 4, 1799).

The learned of all countries, the members and affociates
of the Inftitute excepted, are admitted to this competition.

Among the great number of authors who at all times have
employed themfelves on the human underftanding, there are
a few only who have paid attention to the means which might
augment or direét its powers. Engaged only in refearches
refpecting its caufes, or occupied with defcribing its effects,
they have for the moft part been only able painters or obf{cure
metaphyficians, ~
You. L H On

98 French National Inftitute.

On the fuggeftions, however, of fome men of genius, it
has been found neceflary to abandon enquiries into the firft
caufes, and to direct our attention to the means of improv-
ing the underftanding. :

But the moft powerful means of the progrefs of the human
mind have been obferved in figns.

The firft philofophers who turned their refleétions to the
charagters of writing, the accents and articulations of the.
voice, the movements of the vifage, the geflures and different
attitudes of the body, faw in all thefe figns only means,
either eftablifhed by nature or invented by men, for the com-
munication of their thoughts.

A more profound examination fhewed that figns were not
merely deftined to ferve as a communication between minds.
Notwithftanding the authority of fome great men, who con-
fidered them as fhackles to the juftnefs and rapidity of our
conceptions, thefe philofophers dared to advance that a man
feparated from any commerce with his fellows, would ftill
have occafian for figns to convey the full meaning of his
ideas.

In fhort, fome have imagined that they obferved in figns
a much more aftonifhing fervice rendered to reafon; that is,
that the exiftence of the ideas themfelves fuppofed the ex-
iftence of figns, and that men would be deprived of all ideas
if they were deprived of all figns.

So that they have judged figns neceffary not only for the
communication of ideas, for combining ideas newly acquired,
and for forming new ideas, but ftill for having firft ideas—the
ideas which proceed more immediately from the fenfations.

If a certain influence of figns on the formation of ideas is a
thing inconteftable and univerfally acknowledged, the cafe is
not the fame with the degree of this influence. Here opi-
nions, are divided, and what fome confider as axioms, others
treat as abfurd paradoxes,

The Inftitute. waits to receive memoirs, which by new.
refearches, and new illuftrations, may difpel the uncertainties

that

Society of Medicine at Pavis. 69
that obfcure this important fubjeét, and be proper to unite
every opinion. ee

Tt prefumes, that among the numerous queftions which the
fecundity of the fubject of the prize may give rife to, the
author ought not to forget to anfwer the following :

1. Is it true that fenfations cannot be transformed into
ideas, but by the means of figns? or, what amounts to the
fame thing, Do eur firft ideas effentially fuppofe the affiftance
of figns ?

2. Would the. att of {peaking be perfec if the art of figns
were carried to perfection ? ;

3:.In the fciences where truth is received without cons
teftation, are we not indebted for this to the perfeCtion of:
figns ?

4. In thofe which furnifi eternal fubjec for difputes, is’
not difference of opinion the neceffary effect of inexactitude
in the figns ? ;

5. Are there any means of correcting figns badly made, and
of rendering all the fciences equally fufceptible of demon-
{tration ?

Medical Society.

THE Society of Medicine at Paris had propofed as the
fubje&t of the prize of 300 francs, to be adjudged this year,
the following queftion ;

“ What are the advantages and inconveniences of oo
different methods of treating the aneurifm?” But.as this’
queftion was not fufhiciently expiained, the fociety decreed,
in its public fitting of Floreal 22d (May 11), that the quef-
tion fhould be propofed anew, and the prize adjudged in the
public fitting of Floreal 22d, 7th year.

It propofed, in the fame fitting, as a fubje@ for the prize
to be adjudged on the 22d of Brumaire, 8th year,

_ © To determine by accurate experiments what may be the
influence of oxygen in the animal ceconomy, and, above ails
in the treatment of difeafes both internal and external ?”

H2 Abftr atk

?

E .100. J

Abfivad of the Proceedings of the Claft of the Phyfical Sciences.
of the French National Inftitute, from the 15th of Nivofe laf
(January 4) till the 15th of Germinal (April 4).

THE papers prefented to the Clafs of the Phyfical Sciences.
of the Inftitute, by its members and affociates, during the
above quarter, chiefly related to rural ceconomy, the veteri-
nary art, and chemiftry.

Experiments lately made on horfes, fheep, goats, and rab-
bits, prove, that thefe animals die fpeedily, and with con-
vulfions, when they have eaten a certain quantity of the leaves
or berries of the yew. Citizen Daubenton thinks that this
tree is dangerous ; that it ought not to be tranfplanted into
countries which nature has preferved from it; and that it
would be much better to deftroy than to cultivate it.

, Citizen Celly, in a memoir on the utility of employing
analogy in the natural fciences, and on the application of
botany to promote the progrefs of rural ceconomy; endea-
vours to prove, that the properties of bodies being a confe-
quence of their organization, the more relations there are
between them, the more the ufes for which they can be em-
ployed are approximated.

Citizen Gilbert fhewed the neceffity of fubjeéting all the
operations of agriculture to comparative experiments, in er-
der to enable the rural fciences to make that progrefs of
which they are fufceptible. He thinks it would be neceffary
to form rural eftablifhments deftined to enquire into the beft
procefies, both for the cultivation of vegetables and the ame-
lioration of the breeds of domeftic animals.

Citizen Tenon prefented a memoir, containing a compa-
rifon of the methods in which manducation is performed in
man, the horfe, and the elephant. —

‘ Citizen Chabert communicated refleQtions on a difeafe
among horfes, known under the name of immobility (immo~
bilité), not yet defcribed, and which has a great affinity with

: that

French National Inftitute. Yor

that known among the human fpecies under the namé of the
catalepfy.

An offeous tumour which arofe in the ham of a horfe, gave
occafion to Citizen Huzard to make fome reflections on the
origin of that malady, and the means of curing it, when it is
treated according to its principle.

Citizen Lelievre announced that he had lately difcovered
im France fulphate of frrontian in a ftriated mafs. It was
found, at the depth of 15 or 16 feet, in a clay pit (glaifiere),
which has been worked for fome years, at Bouvron, near
Toul.

Citizen Dolomieu fhewed fome of the fulphate of frontian,
which he had brought with him from Sicily, and which, as
well -as the preceding, had been analyfed by Citizen Vau-
quelin,

It is well known that the nitro-muriatic acid is the true
folvent of gold, and that this metal may be recovered from
its folution by fulphuric ether. Citizen Sage fhewed a gold
precipitate fufpended between the ether and the nitro-mu-
riatic acid, under the form of {mail threads or flakes, and at
the bottom of the flafk, in little brilliant maffes, on which
were obferved triangular lamellz, the elements of the cryf{-
tallization of that metal.

Citizen Chaptal read a memoir on a new mode of manu«
facturing verdigrife. This new procefs, practifed at Mont.
pellier for fome years paft, confifts in caufing the refidue
(marc) of grapes to ferment, and of putting it in layers be-
tween plates of copper, to develop the metallic oxyd, called
verdigrife.—This method is fuperior to the old one, as it is
much eafier, and attended with lefs expence, becaufe it re-
quires no wine.

Some experiments of the fame chemift prove alfo that
white lead may be made in the fame manner.

The fame chemift read another memoir on the acetite
of copper, or diftilled verdigrife. He gave an account of
feveral experiments to oxydate copper with more advan-

H 3 tage,

102 Society of the Arts at Hamburgh.

tage, and-to rénder it by thefe means foluble inthe acctous
acid.
_, Citizen: Berthollet communicated a notice on.a particular
acid which he had difcovered, and to which he gives the’
name of the zoonic acid, becaufe it is extracted, eflentially
from animal fubftances. (See page 68 of this Number.)

» Citizen Dolomieu read a memoir on the tourmalines
found in Mount St. Gothard, the object of which. was to ex-,
amine, how far colour, confidered as a charaéter of {tone,
can determine its nature ?

Laftly, the new experiments of Citizen Vauquelin, on the
red lead of Siberia, and the;new earth which he found
in the beryl, or aigue marin, were the fubjedt of another -
memoir.

HAMBURGH,

.. THE fociety for promoting the arts and ufeful manufac-
tures have propofed a prize.of 40 ducats, to be given to the
author of the beft anfwer to the following queftion :

“ What are the beit means, confirmed by experience, to
fecure wooden work wafhed by the fea, fuch as fluices,
buoys, fignals for fhips, &c..and even-fhips themfelves, from
being, deftroyed by the fhell-worm (teredo navalis), which,
as is well known, pices through! wood and haftens’ its
‘decay 2?

The fociety will dbniider it effay as the beft, which pro-
pofes means of a cheap! nature, known by experience to be
effectual, and which are) either-as: durable as the wood
itfelf to withftand the ‘effets of the waves and the ice, or
ean be renewed from time to time without inconvenience,
and withour injury to the works they are intended to pre--
ferve. All the means hitherto propofed for the like pur-
pofe, fuch as covering the wood with copper, lead, .&¢, are
excluded from the prize ; becaufe thefe, befides being pe-
rifhable in water, are liable to be ftolen, and in many cafes
¢annot be applied, No paper, alfo, can be entitled to the
prize, unlefs the means propoled j in it have been proved by

experience

Teylerian Society at Haerlem. 103

epintche to be effectual... The fociety, however, ‘will with
thankfulnefs receive papers of this kind; the means pro~’
pofed will be fubjected to a trial of two years; and if they
are then found to anfwer the purpofe, a fuitable reward wilt
be adjudged to the inventor.

The effays on this fubjeét, infcribed with a motto, and
accompanied by a fealed note containing the name of the
author, muft be tranfmitted to the fociety before Chriftmas

1798.
HOLLAND.

THE members of the Teylerian fecond fociety at Haer-
lem have propofed the following prize queftion for the year
2790 :

“¢ What are the caufes why moft nations have made choice
of metals, particularly gold and filver, as the reprefentative
figns of wealth and riches ?- What are the advantages of this
circulating medium, fo generally adopted, and what are the
difadvantages connected with it? And can nothing elfey
equally durable, and attended with benefit and advantage, be
invented in its ftead ?”

The premium for the beft anfwer is a gold medal equal in
value to 400 Dutch florins.

The anfwers in Dutch, Latin, French, Englifh, or Ger-
man, with a fealed letter containing the name of the author,
mutt be tranfmitted to Teyler’s foundation-houfe at Haerlem,
before the firft of April 1799; for the prize will be adjudged
on the firft of November, the fame year.

The fociety have alfo announced, that as no anfwer had
been fent in before the expiration of the fixed period to the
prize-queftion of 1796, refpecting the conflitution and form.
of government of the Grecian republics, and their influence
on the happinels or unhappinefs of their citizens, they pror
pofe it once more in the following form :

« What influence has a republican form of government on
the happinefs or unhappinefs of citizens ? and, How far can
this influence be explained and confirmed by examples

H4 drawa

104 Roman National Inflitute. >
drawn from the. hiftory of the’ ancient Rreck. and, Roman.
republics ©” ) Bs

_ The: fociety require the anfwer to this queftion to be.
tranfmitted in the like manner before the firft of April 1799».
that the adjudication of the Prize may be made alfo on the
icf of November,

ROME.

IN bastena dade of the 368th article of the Conftitution of:
the new Roman Republic, the citizens who are to compofe
the members of the National Inftitute were nominated in
April laft by the French general. ‘It is divided into two
claffes :—that of the fciences, mathematics and phyfic ; and.
that of philofophy, the belles lettres, and the fine arts. - The
firft is fubdivided into fix feQions—The mathematics, che-
miftry, anatomy, phyfics, natural hiftory, and agriculture 5
and the fecond into fix fetions alfo, viz. philofophy, hif-
tory and antiquities, poetry and mufic; the political fci-
ences, grammar and eloquence; the art of defign,

ASTRONOMY.

Mr. Herscuey has lately difcovered four new fatellites
to his planet; fothat there are now fix. ‘This difcovery was
made by a telefcope of 30 feet, which he had conftructed
for the Obfervatory of Madrid. The firft notice that La-
lande had of this difcovery was from Gotha, the Prince of
which is fond of altronomy: he laments, in a fhort notice
which he publithed upon this fubjeét, that for fome years
he has not received from Mr, Herfchel any account of his
difcoveries in the heavens.

Paris, 30 Pluviofe, (Feb, 18.)

Mercury and Venus have been obferved to pafs over the
Sun’s difk, under the form of black fpots ; but no perfon ever
before faw a comet in the like fituation, Citizen Dangos,
_ an able aftronomet of Tarbes, on the hia of January laft
made

Aftronomy. 105
made an obfervation of this kind. He faw, during twenty
minutes, a black body, round, and well defined, crofs the
face of the fun, and he remembers to have feen fomething
fimilar in the year 1784. LALANDE.

Paris, 2 Germinal, (March 22, 1798.)

The fun had been feen fome days without any fpot, but on
the 29th of Ventofe (March 19) there appeared a fmall one
en its eaftern limb. It had arrived there in the night-time, as
well as that which was formed in the prefent decade. It
will employ thirteen days and a half to traverfe the fun’s
difk, according to the time of the fun’s rotation, in regard
to the earth, which I have determined to be 27 days 7 hours
and 37 minutes. In comparing with each other the large
fpots vifible by the naked eye in the years 1752, 1764, 1777,
and 1778, I confider them te be the fame fpot, or at leaft
formed at the fame point of the folar globe, where there is
probably a local caufe which from time to time produces at
the fame place the fame phenomenon. LALANDE.

Citizen Mefficr, aftronomer of the National Inflitute,
‘about feven in the evening on the 23d of Germinal (April
11) difcovered from his obfervatory a new comet in Tau-
rus, near the Pleiades, and in the parallel of the principal
flar of that conftellation, with which it was compared at
$h.58m. 16fec. of true time; its right afcenfion being
49h. 19m. 47fec, and its declination 23h. 22m. 55fec. north.
Next morning, the 24th, the comet was compared again
with the fame ftar, at 8h. 25m. 46fec. Its right afcenfion
was found to be 50h, 52m. 55fec. and its declination
25h. 18m. 58fec.

This comet, which is fmall, round, and brilliant, has no
tail, and cannot be feen by the naked eye. On the 25th its
light was increafed ; which feems to fhew that it is approach-
ing the earth,

This is the 20th comet which Citizen Meffier has difco-
vered

106 Earthquakes.
vered fince 1758, and the 49th which I have obferved. The

number of the comets known now amounts to 88, according
to the catalogue which is given in my Aftronomy.
LALANDE,

' Francis Lalande, nephew of the aftronomer of that name,
has lately carried to 45,000 the number of the ftars which
he engaged to determine.—An immenfe labour, which no
aftronomer before ever ventured to undertake, and which
was a defideratum in aftronomy.

Dr. Burckard, an able aftronomer of Gotha, now at Paris,
has calculated the orbit of the comet lately difeovered. He
finds that it paffed its perihelium .on the 3d of April, at 7
hours, in 3 figns, 12deg. 56m. at the diftance of ,0487 from
the fun: the inclination of its orbit is 45deg. 18m. and it
interfects the ecliptic at 4 figns, odeg. 44min.

M. de Lalande, in a letter which he lately wrote to Ma-
jor von Zach, at Gotha, informs him, that the Turkifh am-
baffador at Paris is remarkably fond of aftronomy, and at-
tends regularly the Lyceum, where he has a fopha appro-

’ priated for his own ufe. His interpreter Codrika has tranf-

lated one of M. de Lalande’s works into the Greek lan-
guage. The Turks at prefent feem to apply with fome at-
tention to the cultivation of mathematical knowledge.—
M. de Lalande fays that a mathematical fchool has been
eftablified at Conflantinople with four profeffors, and —
that the number of pupils amounts to fifty. Logarith-
mical tables are now printing in that city, with Turkifh
types.

; sien EARTHQUAKES.

LETTERS. received from Bencoolen, Taponooly, and
Padang, of the 5th and 7th of March 1797, give the fol-
lowing relation of an earthquake that happened on the weft
coaft of Sumatra on the goth of February :

_The vibratory dhocks of this earthquake are ftated, on
competent authority, to have continued for three minutes,
‘ and

ae

— Barthquakes. 107
and to have recurred at intervals, during a {pace of three
hours, from its beginning, till the fhock had completely
ceafed. At Padang, the houfes of the inhabitants are almoft
totally deftroyed, and the public works much damaged.
The fnow Padang, lying at anchor in the river, was thrown,
by the fudden rife of the fea, upwards of three miles in fhore,
where the ftill remains. The number of lives loft at Padang
on this. melancholy oceafion exceeded 300. Of thefe, fome
were cruthed under the ruins of falling houfes; fome were

; literally entombed alive by the earth clofing upon them ; and

others were drowned by the fudden irruption of the waters

e the ocean. The effects of this awful convulfion of nature

do not appear to have extended to the northward of Tapo-
nooly; as at that place little or no damage was fuftained.
It appears to have come from the fouthward, and is fuppofed
to have extended as far as Bencoolen; but no accounts having

been received at Taponooly or Padang, from the fouthward,

between the time of the occurrence of the earthquake and
the date of the letters, the extent of this calamity has not
been afcertained.

At Natal, the refidence of a fubordinate of Bencoolen,
yery confiderable damage was fufiained, and feveral houfes
thrown down, but no lives were loft. It is however feared,
when the particulars fhall have been colleéted from the
different quarters on the weft coaft, where the earthquake
was felt, that the fam, both of lives and property deftroyed,
will be found much greater than yet apprehended.

A letter from Metz, dated Ventofe 30, (March 20) ftates,
that at fix in the morning of the 24th a fhock of an earth.
quake had been felt at Sarreguemines, Blifcatel, and other
gomnyunes of the department of la Meurthe. No precife
obfervations were made on its direction. It was fo violent

at Bitche that it raifed up part of the arch of the bridge, fo

#s to render it dangerous to be pafled.

. A fa& which feems to explain this phenomenon is, that
the circumference where it took place cantains feveral mines
cy AVM of

r0$ Voyages and Travels.

-
of naphtha. One of thefe burns continually, lke the /o/-
faterra at Naples,

Some days before a flaming meteor rofe from the earth,
between Fey and Veron, three leagues to the fouth of Metz.
Its difappearance was followed by a detonation which fhook
the atmofphere to a confiderable diftance around.

VOYAGES AND TRAVELS.

CITIZEN OLIVIER, who has been travelling through
Perfia by orders of the French government, writes from
Confiantinople, dated Frimaire the 18th laft, that he has
brought from Perfia, Babylon, the deferts of Arabia, the
environs of Aleppo, Cyprus, the mountains of Caramania
and Afia Minor, more than two hundred feeds in good pre-
fervation ; many medals of gold, filver, and bronze, Roman,
Greck and Parthian; fome mummies of children, and of
the facred birds of the Egyptians; fome interefting manu-
{cripts, &c. Proceedimg then to the adtual fituation of
Turkcy, he concludes, from its depopulation ; the great dimi-
nution of its revenues; the deferted ftate of its plains,
which daily increafes, by the oppreffion and impunity of the
Pachas; the revolts of the latter; the mutinies and infub-
ordination of the Janiffaries, that this extenfive empire 18
approaching to a fudden fall.

A gentleman of the name of Brown, who refided feven
years in Abyffinia, is now in Egypt. He is faid to have
proceeded much farther weft than Mr. Bruce, with whom
be agrees in moft points: he intends to publith an account
of his travels, which’no doubt will afford much information
as well as amufement. | iB

Frederick Horneman, the only fon of a clergyman’s widow
at Hildefheim, a young man of an athletic conftitution, 2
great mechanical cenius, pofleffed of confiderable knowledge
and ‘firmne(s of cltaraéter, impelled with an infuperable ime
pulfe to a journey of difcavery in Aftica, is now on his way
from Cairo over Cafchna to Tombuétu. He travels at the

expence of the African Affociation. ee
BOTANY,

{ 109 J ers

. BOTANY, GARDENING, AGRICULTURE.

A LETTER from Mr. Anderfon, Director of the Botanic
Garden of St. Vincent’s, dated the 24th of December lait,
has been received by the Society of Arts, Manufactures, and
Commerce, which brings very pleafing accounts refpecting
the thriving ftate’ of the bread-fruit-tree. In 1793, fifty
young plants were carried from Otaheite by Captain Bligh.
They were then from 6 inches to 2 feet high. They are

now 30 feet and upwards, and the circumference of the ems.
from 3 to 3: feet.
: It was feared, when they were firft carried over, that they
would not haye ftrength to ftand againft the violent hurri-
canes of the Weft Indies; but the wood is found, en the
contrary, to be extremely tough, and well qualified to refitt
the fevereft gufts of wind.

The bread-fruit weighs from 4 to rolbs. each, and is m
its greateft perfection about a week before it is quite ripe.
When bakgd, which is the beft method of cooking it, it is
equal, if not fuperior, to bread. From its firft appearance,
it is three months before it is fit for eating.

The trees are propagated by fuckers, which arife in abun-
dance. 3;

_ The Society alfo received fome bifeuit made from the.
fruit, which they agreed was an excellent fuccedancum for
bread.

Some curious experiments, which promife important bene-
fits to mankind, have lately been made by Sir Francis Ferd,
to determine whether oxygene, or vital air, has any effects _
upon vegetation different from common atmofpheric air.
He found by repeated trials, that flowers, and other plants,
fprinkled with water that had been previoufly impregnated
with oxygene gas, grew much more vigoroufly, and even dil-
played more beautiful tints than fimilar plants on the fame

ground treated with common water, The water was im-
pregnated by a very fimple procefs—Bottles filled with water,

- j were

110 Botany and Agriculture.

were inverted over a common pneumatic apparatus, and
oxygene gas introduced till a third or fourth part’of the
water was difplaced: the bottles being then flopped, were
agitated for fome time till it was believed the water had taker
up all the gas that it could receive.

We know not whether the refiduum of the gas’ has yet
been fubmitted to any teft, to determine whether it under-
goes a change by being thus wafhed by the water; but, no
doubt, the fubjeét will receive that attention which it merits
from thofe who have the means and opportunity of dagy 1:
and following out the experiments.

It appears to be a fubjeét worthy of enquiry, what would
be the beft and eafieft methods for impregnating water with
oxygene ? or, which would be perhaps ftill better, what
would be the beft fubftance to be thrown upon land to ena-
ble it, or the moifture it contains, to abforb the greateft quan-
tity of oxygene from the atmofphere ?

Some experiments have been lately made in the neigh=
bourhood of Briftol, under the immediate imfpedtion of one
of the members of the Bath Agricultural Society, with re-
{pect to the culture of madder; the refult of which is, that
madder may be produced in large quantities in England, and
fold to the dyers at a cheaper rate than that imported, being

Of a quality equal to that grown in Zealand. In 1756 the
king of France iffued an ediét, exempting from Jand-tax

for the fpace of 20 years (that is to fay, in all fields newly

broken up) all cultivators of madder in drained marfhes and

other wafte and neglected grounds. In 1762 the Board of

Agriculture held at Hesatais made it plain to all perfons ‘

concerned in dyeing, that madder raifed in that diftriét, and

“ufed while the roots were frefh gathered, gave a finer tinc-
ture than the Zealand madder, and went further in the pro~

portion of eight to five. In the fame year it was ordered in

council, that no tax, for the fpace of 20 years, fhould be

levied upon grounds newly broken up, provided the faid

grounds had lain 20 years in an uncultivated ftate. In 176%

there

Mineralogy. iit

there were 13 focieties exifting in France, eftablifhed under
the patronage of government, for promoting agriculture;
and thefe 13 focieties had 19 co-operating focieties belong-
ing to them, whenever it happened that a diftri& was too
large to be effectually taken care of by one fociety. All
packets and letters of correfpondence to and from thefe
focieties were exempted from poftage.

Paris, June 22, 1798.

CirizeN Baupin, commander of Ja Belle Angélique,
who, with feveral botanifts and naturalifts, was fome time
ago fent on a voyage of difcovery by government, has jut
returned from America, and has brought with hin the
richeft colleCtion of living plants ever feen in Europe. He
has brought home in all 3500 exotics, among which are
feveral cabbage trees, cocoa-nut trees, and alligator pear
trees (/aurus Perfez). Some of the trees are 25 feet in
height, and from 12 to 15 inches in diameter. Befides the
collection of living and dried plants, he has brought with |
him various fpecimens of wood, birds, infects, and many
other objects of natural hiftory.

Captain Baudin on his arrival attempted to enter the port
of Havre, as being the moft convenient for tranfmitting his
collection to Paris, but was prevented by the Englifh fquadrom
which blockades that port. The Englifh commander told
him his orders were fuch, that he could fuffer no veffel to
entre Havre; but, in avery handfome manner, directed hum
to proceed to the eaft of Fecamp, the only place in the chan-
nel not blockaded by the divifion under his command.

MINERALOGY.

A VEIN of cobalt was fome time ago difcovered in, ae
Wherry mine near Penzance in Cornwall, which, we are
happy to announce, has turned out very rich; but as they
have no perfon there perfectly acquainted with the procefs of
fmelting it, it is to be feared that. its true value will never be

fully known. It is to be lamented that there are few. or no
fkilful

413 Weights and Meafures.

fkilfal mineralogifts in Cornwall ; and that we have no gdod
pradical work in the Englifh language to enable them to ap~
ply to further ufe, what little kAidwledas they have acquired’
from working the rich tin and copper mines in that county.
Kirwan’s Mineralogy is an able fcientific claffification and
brief analyfis of the fubjects of which he treats; but we
want fome popular works like thofe of Profeffor Klaproth.’
For want of proper books of this kind in the Englifh lan- | —
guage, there is reafon to believe that many valuable mincral
produéts are every day loft in Cornwall; for every fubftance:
that appears not to poffefs the characteriftics of the) tin or
copper, of which they are in fearch, is thrown away among
the rubbifh. This was the cafe with the cobalt vein, when
a gentleman of more knowledge than. the proprietors haps
pened to obferve it. ee
mer
WEIGHTS AND MEASURES.
IN the month of March laft, Citizen Aubry prefented to
the Council of Five Hundred a work containing the prapor-
tions between all the meafures poffible, and a fimple method,
to difcover thefe proportions. This work is confidered in
France as a certain ftep towards an univerfal ftandard fo,
much defired, a
Sir George Evelyn Shuckburgh has lately laid before the
Royal Socicty the refult of many years application and ftudy,
upon the fubje& of a univerfal ftandard for weights and,
meafures. He proceeds upon the principles of the late in-,
genious Mr. Whitehurft, and ufes the identical inftruments.
he employed. The mean meafure is derived from the dif-
ference in length of two pendulums performing ; a different
number of ebanaione ina minute.

THE

PHILOSOPHICAL MAGAZINE.

I, Defeription of the Mechanifm of a reficéting Telefcope twen-
ty-fix Feet in Length, conftruéted near Kiel in Holftein, by
Profeffor SCHRADER. From the Account, publifbed in
German, by the Profeffor.

An hexagonal frame ABCD, (Plate V.) formed of ten
inch fquare beams, joined together, refts upon twelve ftrong
pofts driven into the eround. On the fmaller hexagon of this
frame ftands the under part of the building aaaa, which rifes

‘to the height of fourteen feet, and is fupported by braces or
fpurs. “On the beams which compofe the upper frame of
this part of the building lies a horizontal wheel, 12 feet in
diameter, which is made faft by means of iron fcrews. “A
fmall hexagonal cabin of the like diameter; and 7+ feet in
height, forms the moveable upper part of the whole build-
ing, to which is affixed the mechanifm that ferves for the
motion of the telefcope.

Through the middle of the fmall cabin arifes a very
ftrong axle 4 4, the upper part of which 4 may. be feen pro-
jecting above the flat top of the cabin. At c the axle turns on
a fteel gudgeon which moves in a focket, fitted into a ftrong
beam dd, moveable in a horizontal direction. This beam,

Vou. I, I by

114 Account of the Telefcope at Kiel.

by means of iron wedges ufed as in the Dutch windmills, can
be fo elevated that the whole upper part of the building may
be moved upon eight rollers placed above the horizontal
wheel. A fimall vertical cylinder ff proceeds along the fide
of the cabin down to the horizontal wheel, and at the lower

~ end has an eighteen inch wheel g with twelve teeth, which
fit into thofe of the large wheel. The {mall wheel, to de-
fend it from the injuries of the weather, is inclofed in a
box. To the top of this fmall cylinder, which rifes three
feet above the platform, is affixed a crofs-bar lever w, and
the cylinder has its poimt of motion in a collar at 4, in which
{mall rollers are applied to leffen the effects of friction. By
turning the crofs the whole cabin moves round its axis, and
the tube of the telefcope IJ, conneéted with it, is thus made
to move alfo horizontally. The vertical movement of the
tube, which was attended with confiderable difficulty, is
effected in the following manner: At the end of the beams
kk, which projeét parallel to each other, on a level with the
upper frame of the building, arife the inclined beams mmn,
joined to the former by mortices at 0, and morticed alfo at
bottom into the uprights of the cabin. They are fupported
by ftrong braces, ‘and, where neceflary, are bound faft with
iron fcrews. To prevent all lateral agitation, Profeffor
. Schrader placed at right angles on the two Horizontal beams
‘kk, and faftened to the cabin, another beam H of fufficient
fireneth, each end of which projects five feet over the
beams &. From thefe ends arife two oblique beams rz and
sz, each of which is morticed as at z, a foot and a half below
the bridle 77, and bound alfo with iron.
~ The mechanifm of the movement of the tube between

this hanging frame-work is fimilar to that of Herfchel’s
telefcope. Along the interior ‘part of each fide-of the frame-
work, from 2 to /, 1s a groove (reprefented in the plate by
pricked lines), and a ftrong oblong rectangular frame moves
in this groove by means of four fmall iron rollers fixed
to the corners with ferews, By the crofs lines wv the
place

Account of the Telefcope at Kiel. 1I5

place of the frame only is marked, In'this frame the tubeis
made to move on a ftrong roller. At the upper end of the
frame is fufpended one box of a tackle of fix pulleys, the
fecond box of which is faftened to the crofs beam // of the
hanging frame-work, and the rope //, proceeding from the
tackle, is wound round the cylinder of a horizontal windlafs,
the handle of which is in part vifible at ¢#. The fecond
refting-place of the tube is in a fork on the top of an iron
rack g, by which the more accurate movement both vertical
and horizontal is effected with the greateft eafe. When
the handle ¢#¢ is turned round, the fliding frame together

“with the tube rifes or falls, and a common {pring catch ap-
plied to the windlafs keeps the tube in that pofition to which
it has been brought. To counteract the weight of the
tube, which increafes according to the perpendicularity of
its pofition, the Profeffor faftened to the end of it a {mall
tackle, the rope of which, carried over a pulley fixed to
the crofs beam //, fuftains a re-aéting weight of 120 pounds.
This weight ats only from the perpendicular fituation of
the tube to about that in which it is reprefented in the plate.
The quick horizontal movement, which is effected by means
of the crofs-bar lever with the cylinder and horizontal wheel,
requires a power of about forty pounds; fo that the obferver

ean, with great eafe, turn the tube round the whole hori-

“zon, though the weight of the conftruétion taken together
amounts to about 12,000 pounds.

From comparing this defcription with the figure in the
annexed plate, it will be feen that the gravity, both on ac-
count of the weight of the hanging frame-work and that
of the tube, muft incline too much to one fide: it was
found neceffary, therefore, immediately after it was con-
ftruéted, to devife the following counterpoife: The two
horizontal beams G G, a foot fquare, which fupport the gal-
lery FF, with the ladder that conducts to the platform,
were made to projeét on a level with the bottom part of the
cabin, The weight of the gallery and ladder caufed a

12 leflening

116 Account of the Telefcope at Kiel.

leflening of the weight towards the oppofite fide; but, a¢
this was not fufficient, the Profeflor made the horizontal
beams to be covered with boards, by which means it ac-
quired fo much ballaft that the centre of gravity of the whole
top refted on the fieel gudgeon c. The {mall balcony con-
tains a feven-feet telefcope ten inches in diameter, which.
the Profeffor fuffers always to remain in the open air, and
ufes as a hand telefcope. For the greater fecurity, a ftrong
iron rod, concealed by the wainfcoting in the infide, is con-
veyed along the floor and to the top of the cabin. The
flower extremity of this rod ends in two branches fcrewed to
the floor, and the upper part rifes one foot above the plat-
form. On the top of it is ftuck the key which ferves for
moving it; and by lefs than half a turn of this {crew, the ob-
ferver is enabled to prevent all agitation of the building, be-
caufe, the rod then prefles with force againft the furface of
the horizontal wheel. Properly, however, there are three
fcrews, forming an equilateral triangle, which effect this
faftening, two of which in the cabin are very fhort, and
the whole are fo arranged, that it 1s neceflary to move the
jong ferew only on the platform. Thus, by its force, it as
it were moves the upper platform from its level, and preffes
it a little, imperceptibly inclined, towards the two ferews,
which by their preffure on the horizontal wheel prevent alt
agitation.

The twenty-fix feet o€tangular tube, conftructed of buards
which are prevented from bending by a number of knees
applied in the infide, and which are made impenetrable to
rain, is fitted to receive a fpeculum of frem 1g to 20 Eng-
lifh inches diameter. At prefent, however, it is furnifhed
with one of only 14 Hamburgh inches in diameter, having
a focus of 26 feet, and which without the frame weighs 80
pounds. Jt is almoft two inches in thicknefs, and towards.
the edge cait conical, fo that the diameter of the polifhed
furface is almoft a quarter of an inch lefs than that at the
back, This in the finifhing and polifhing is of the greateft

utility.

Account of the Telefcope at Kiel. 117

utility. The great weight of the fpeculum requires that it
fhould be always kept in the tube, and this renders neceflary
a peculiar apparatus not requifite in fmaller telefcopes. It
*is well known that large metalline maffes acquire very flow-
ly the temperature of the atmofphere. The confequence
is, that fpecula are very frequently covered with the evapo-
ration from the atmofphere, which condenfes on them. If
the compofition of the metal be not good, the fpeculum foon
becomes tarnifhed. The caufe of this lies in too large a
quantity of copper, which forms a component part of the
mafs, and therefore it muft be combined with a fufficient
quantity of tin. Edwards’s compofition in this refpeét is
much preferable to all other mixtures. By more than forty
experiments Profeflor Schrader difcovered a very good mix-
ture; and fpecula made of it were fo excellent, that they
might be expofed to confiderable evaporation without lofing
much of their fplendour. As in a clofe apartment no body
can be tarnifhed, if a fpeculum be fhut up during hot and
moift weather the above inconvenience can be avoided.
Profeffor Schrader has fecured his fpeculum by a cover made
of brafs rings, eight inches broad, foldered together. The
centre fcrews, as well as the iron circle which keeps the
fpeculum in its pofition, are properly fixed in thefe rings,
and, by means of two capes with handles, which internally
are lined with leather, or, what is better, with the {kins of
moles, the fpeculum is kept perfectly free from air.

The period of the day at which the fpeculum can be un-
coyered for ufe, depends on the length of time which it re-
quires to affume the temperature of the atmofphere. A few
experiments will here conduét to the proper regulation. A
good rule for. guarding againft tarnifhing is, to endeavour
as much as poflible to keep a continual draught of air in
the tube, For this purpofe, feveral fmall openings may be
employed in fuch pofitions that the rain may not penetrate
through them. A {mall ftage for the purpofe of getting at
the fpeculum with more conveniency, is conftruted near

13 the

118 Account of the Javanefe Swallow,

the loweit ftep, to which the tube muft be previoufly turned.
A pole with a knee and a pulley ftands by it, in order to
take out the fpeculum occafionally.. The reafon why the
under part of the building was conftruéted. higher. than
neceflary, was merely that a tube of 30 or 35 feet might
be ufed.

Il. Defcription of the Javanefe Swallow, which confiruéts
eatable Nefis; with an Account of the Manner in which
the Nejls are colleéted.. From the TranfaGtions of the
Batavian Society in the Ifland of Java for promoting the
Arts and Sciences, Vol. ITI.

‘Tuese fmall birds are of a blackith grey colour, in-
clining a little to green; but on the back to the tail, as
well as on the’ belly, this blackifh colour gradually changes

into a moufe colour. The whole length of the bird from

the bill to the tail is about four inches and a half, and its
height from-the bill to the extremity of the middle toe three
inches and a quarter. The diftance from the tip of the one
wing to that of the other, when extended, is ten inches and
a quarter. The largeft feathers of the wings are about four
inches in length. The head is flat; but, on account of the
thicknefs of the feathers, appears round, and to be of a large
fize in proportion to the reft of the body. The bill is
broad, and ends in a fharp extremity, bent downwards in
the form of an awl. The width of it is increafed by a naked
piece of fkin fomewhat like parchment, which, when the
bill is fhut, lies folded together, but which, when the bill
opens, is confiderably extended, and enables the bird to catch
with greater eafe, while on wing, the infects that ferve it
for food. The eyes are black, and of a confiderable fize.
~The tongue, which is not forked, is fhaped like an arrow.
The ears are fat, round, naked fpots, with {mall oblong

apenings, and are entirely concealed under the feathers of -

the

eee ee

ee I ee

———

= ey

: which confiruéts eatable Nefis. 119

the head, The neck is very fhort, as well as the legs and
the bones of the wings. The thighs are wholly covered
with feathers; and the very tender lower parts of the legs,
and the feet themfelyes, are covered with a fkin like black
parchment. Each foot has four toes, three of which are
before and one turned backwards. They are all detached
from each other to the roots; and the middle one, together
with the claw, is fully as long as the lower part of the leg.
Each toe is furnifhed with a black, fharp, crooked claw of a
confiderable length, by which the animal can with great
facility attach itfelf to crags and rocks. The tail is fully as
long as the body together with the neck and the head.
When expanded it has the form of a wedge, and confifts of
ten large feathers. The four firft on each fide are long, and,
when the tail is clofed, extend almoft an inch beyond the
reft. The other feathers decreafe towards the middle of the
tail, and are equal to about the length of the body.

The whole bird is exceedingly light and tender. Ten of
them together weighed little more than two ounces and a
half. The Javanefe call it Zaqwit; but thofe who live in the
mountains, berongdage@ or waled*,

There are two places in particular near Batayia where
thefe birds are found in great numbers. The firft, Calappa
Nongal, lies about ten miles fouthwards from the city; the

_ other, ‘Sampia, is a little more diftant towards the fouth-

welt; but they are both in that range of high land extending

_ towards the fea, which is apparently different from the tae

ridge that extends over the whole ifland. Befides thefe there
are alfo feveral other places in the fame diftrict, or ata
greater diftance from the coaft, which either produce a few,
or are carefully congealed by the Javanefe to whom they are
known.

The two bird mountains before mentioned, called by the
Javanefe caverns (goa), are infulated rocks, hollow within

* Yoerong in the Malay language fignifies in general a bird.
ee ig and

120 Account of the Javanefe Swallow,

and pierced with a great number of openings. Many of
thefe openings are fo wide, that a perfon can enter them
with eafe; others are attended with more difficulty; and fome
of them are fo fmall, that nature evidently feems to have been
defirous of providing for the fecurity of thefe little animals.
On the outfide thefe rocks are covered with a multitude of
ftrong tall trees of various kinds. The infide confifts of grey
calcareous ftone and white marble. ‘To the walls of thefe
caverns the birds affix their fmall nefts in horizontal rows,
and fo clofe that they for the moft part adhere together.
They conftruét them at different heights from 50 to 300
feet; fometimes higher or lower, according as they find
room; and no hole or convenient place, if dry and clean, is
left unoccupied; but if the walls be in the leaft wet or moift
they immediately defert them. :

At day-break thefe birds fly abroad from their holes with
aloud fluttering noife, and in the dry feafons rife fo high
into the atmofphere in a moment, as they mutt feek their
food in diftant parts, that they are foon out of fight. In the
rainy feafon, on the other hand, they never remove to a great
diftance from their holes, as has been often remarked, parti-
cularly in the government of Java, where there are fome
rocks fituated very clofe to the fhore. About four in the
afternoon they again return, and confine themfelves fo
clofely to their holes, that none of them are feen any
more flying either out or in, but thofe which are hatch-
ing. !

They feed upon all forts of infects ighiehi hover over the
ftagnated water ; and thefe they eafily catch, as they can ex-
tend their bills to a great width. Their moft deftruétive
enemy is a kind of hawk (knzkendief), which feizes many of
them as they iffue from their holes; and which people, on
that account, take great care to frighten away by fhooting
at them.

They prepare their, nefts from the ftrongeft remains of
' the food which they ufe, and not of the fcum of the fea or
of

'

which confiruéts eatable Nefis. . 12t

of fea plants *, as has been afferted. This feems the more
probable, as it is known, from experience, that thofe birds
which build their nefts in the two rocks before mentioned
have never been found on the fea-coaft, and could not pof-
fibly fly thither and return again in fo few hours, on account
of the high intervening mountains, and the ftormy winds
that often prevailamong them. The great difference in the
colour and value of thefe nefts proves that their goodnefs

_ depends merely on the fuperabundance and quality of the

infects on which they feed, and perhaps on the greater or
lefs folitude of the place where they feek for nourifhment.
Thofe found on the territory of Calappa Nongal and Goa~-
gadja are exceedingly grey, and worth one third lefs than
thofe produced in the territory of Sampia; and the latter
again are not to be compared with an excellent fort which
are every year imported from Ternate and Paffier, or which
are to be found on the furrounding iflands, particularly to
the eaft of Borneo.

Thefe birds employ two months in preparing their nefts ;
they then lay their eggs, on which they fit for fifteen or

' fixteen days. As foon as the young are fledged, people

begin to colleét the nefts, which is done regularly every
four months; and this forms the harveft of the proprietors
of thefe rocks.

The bufinefs of taking down the nefts is performed by
men accuftomed from their youth to climb thefe rocks.
They conftruét ladders of reeds (bo/chrotting) and bamboos,
by which they are enabled to afcend tothe holes ; but, if the
caverns are too deep, they employ fhip-ropes. When they
have got to the bottom of the caverns, they place bamboos
with notches in them again{t the wall, if thefe be fufficient

* This has been hitherto generally believed, and copied from one
naturalift by another. Houttyn himfelf in his Natwurlyke Hiftcrie, vol. i.
part v. p. 607, gives a defcription of the bird aswell as of its manner of

feeding, which is confiderably different from the above,
in

122 Account of the Javanefe Swallow,

in order to get up to the nefis; but if they cannot reach
them in this manner, they ftand on the ladders and pull the
nefts down with poles of bamboo made for that purpofe.
There are alfo certain holes to which people can afcend by
means of ftages made of bamboos; but thefe are exceed-
ingly few.

This employment, which is attended with great danger,
cofts the lives of a great many men, and particularly of
thieves, while attempting to rob thefe caverns at improper
feafons. For this reafon, fmall watch-houfes are every-
where built in the neighbourhood.

The mountaineers, who are thofe chiefly aceuftomed to
this employment, never undertake their labour till they have
flaughtered a buffalo, which is the ufual preparation made
by the Javanefe for all their undertakings. On fuch oc-
cafions they mutter over a few prayers, anoint themfelves
with aromatic oils, and fumigate the holes with {weet-fmell-
ing fubftances, which, according to their ideas, are things
all highly neceffary. At the chief of thefe caverns in the
ifland of Jaya, a particular protecting female deity is wor-
fhipped under the name of Raton Laut Ridul, or princefs of
the fouth fea. A fmall hut with a covered fleeping-place is
there appropriated for her, together with various elegant
articles of drefs, which no one buta princefs muft approach’;
‘and every Friday when the nefts are taken down incenfe is
continually burnt, and the body and clothes of every one
who intends to afcend the rocks muft be expofed toit. The
other Javanefe are not fo fuperftitious, and content them-
felves with much fewer ceremonies. To afford them light
in the cavern, they employ torches made of the refinous
gum of a large tree called caret, and the inner bark of the
arek-tree.

The colleéting of the nefts continues no longer than a
month, and, as already mentioned, may be repeated three
times in the year, Some believe that it may be done a

fourth

which confiruéts eatablé Nefls. 123

fourth time; but this is not probable, as all experienced
people brought up to this employment confidently affert,
that a neft as long as it remains entire is continually enlarged
by the bird, or made thicker, until it is entirely deferted by
her when it has become dry or hairy in the infide.

When the nefts have been colle&ted, no farther trouble
is neceflary than to dry them and clean them, after which
they are put in bafkets and fold to the Chinefe. The price of
them is:variable, and depends on their whitenefs and fine-
nefs. Some of them have a grey, and others a reddith ap-
pearance. Thofe of the beft fort are exceedingly fearce,
They are fold at the rate of from 800 to 1400 rix-dollars per
125 pounds. This high price, and the infatiable avarice of
the Chinefe, give rife to much difhonetty and thieving ;
efpecially as the Chinefe make no ceremony of bribing the
watchmen with money, opium and cloth; and this, even
with the utmoft vigilance, cannot be entirely prevented.

The two places above mentioned, Calappa Nongal and
Sampia, belonged formerly to the Dutch Eaft India company}
but as the advantages arifing from them were in part much
leflened by the Javanefe, and in part not well underftood,
government refolved, in the year 1778, to fell them by
auction to the higheft bidder, and received for them almoft
a hundred thoufand rix-dollars, afum far exceeding what was
generally expected. Befides thefe, there are feveral other
places of the like kind, in the above range of mountains,
though of lefs importance. There are two or three alfo in
the high land in the interior parts of the country, and feve~
ral {mall ones which are kept concealed with great care. Three _
confiderable bird mountains, Goa Daher, Gede, and N anga-
fari, are fituated in the government of Samarang in Java ;
and thefe are wafhed by the fea, which forces its way fo deep
into the latter, that fifth may be caught in it. In thefe places
the nefts are of an excellent quality ; but it is exceedingly
dangerous to cgllect them on account of the fteepnefs of the

5 rocks

124 Account of the Javanefe Swallow,

rocks and the violence of the furf, and therefore a fufpended-
apparatus made of bamboos muft be employed. ,

About 2500 pounds weight of thefe nefts are collected
every year in the ifland of Java.

There are bird caverns alfo in Bantam and the ifland of
Sumatra; but the inhabitants of the former are fo mdolent,
and the government fo bad, that rice even is not fown, nor
is any other article neceffary for the fupport of life culti+
vated. The Chinefe have never ventured to penetrate into
the interior part of that kingdom, and have no intercourfe
with the mountaineers ; {o that little can be expected from
that quarter.

The young birds are eaten both by the Javanefe and the
Europeans in India, but it is difficult to procure them.
They are confidered to be very heating. The nefts, on the
other hand, when they have been boiled to a flimy kind of
foup, expofed in the night-time to the dew, and been mixed
with fugar, are exceedingly cooling. The Javanefe employ
them therefore, with much advantage, in violent fevers.
The author of this paper faw alfo that, when prepared as
above, they were prefcribed with good fuccefs for fore throats
and hoarfenefs. This remedy, in all probability, has been
borrowed from the Chinefe, who, as a rich merchant of that
nation who carried on a great trade with thefe nefts affured
the author, eat abundance of them during the winter, be-
caufe fore throats are then very common in the northern
part of that extenfive kingdom, on account of people fitting
fo much over the fire.

But this nourifhing and ftrengthening quality, fomuch 4
extolled, the author was not able to difcover, though he ufed*

a confiderable number of thefe nefts, prepared different
ways, in order to be convinced of the truth. He caufed
them to be examined by able chemifts; but nothing more
could be obferved, than that the folution prefented a weak

gum

which confirudls eatable Nefts. 125

gum with.a difagreeable tafte, which perhaps might be of
fome ufe in flight indifpofitions of the breaft.
Thefe nefts, therefore, are merely an article of luxury to
- ornament the tables of the rich. The Chinefe are remark-
ably fond of them. After being foaked and well cleaned,
they put them, along with a fat capon or a duck, into an
earthen pot clofely covered, and fuffer them to boil for
twenty-four hours over a flow fire, which they call timmen;
and on account of this addition the whole difh acquires a
more lufcious tafte.

The trade carried ‘on with thefe nefts was fome years ago
not fo confiderable, but of late it has much increafed. The
high price of them in China, which is ftill advancing, makes
Batavia the principal mart of this commodity, which, as the
company have now given it up, is employed very advantage~
oufly by the inhabitants to leffen the prejudicial exportation
of {pecie.

That this fpecies of fwallow is not to be found in China
is now fufficiently known.

Linneus in his Sy/t. Nat. gives, as a ‘diftinguithing mark
of the Hirundo efculenta, that it has white fpots only on the
feathers of the tail. The fmall birds in Java, however,
which conftruét thefe nefts, have fpots neither on the tail

nor on any other place. The tail feathers are entirely of
one colour, blackifh grey above, and a little brighter below.

Rumph fays of his capodes marine, that the feathers of the
tail were fpotted, and that the breaft alfo was fpeckled black
and white.

Valentin, in his defcription of the fmall fwallow which
conftruéts eatable nefts, mentions neither {pots nor {peckles,

-and fays only that the belly was undulated white and black.
If thefe are to be confidered as effential differences, it will
follow that there are two kinds of thefe fwallows: one with
a {peckled breaft and white fpots on the tail feathers, and
the other without fpots or fpeckles. A third kind of thefe
f{wallows would be thofe called momos or bocrongitams, Thefe -

alfo

126 — Procefs followed at Aftracat

alfo prepare their nefts of eatable fubftances, buf, on account

-of the number of {mall feathers and other impurities mixed
with them, are not fit to be ufed. People therefore en-
deavour, as much as poflible, to exterminate them, as they
fpoil the habitations of the better kinds. They are diftin-
guifhed from the latter merely by being larger, and having,
the legs down to the feet covered by {mall feathers.

Ill. The Proce/s followed at Afiracan to give to Cotton Yarn
a Blue, Yellow, or Green Dye. From Neue Nordifche
Beytrige, by Profeffor PALLAS.

Ts E manufacturers at Aftracan, befides red cotton yarn,
the procefs for dyeing of which has been given in the pre-
ceding number of this Journal, prepare alfo blue, yellow, and
green, which they give out to be dyed by regular dyers.
The procefs which they employ is briefly as follows :

The principal dye is the blue, which is employed both for
cotton and filk. To prepare it, the indigo or blue dye-ftuff
is finely pounded, and diffolved in water by a gentle heat in
large earthen jars, feven of which ftand in brick-work over
the fire-place, at the diftance of about an ell and a half from
each other. About two pounds are put into each veflel.
Five pounds of the foda or kalakar, mentioned in the procefs
for the Turkey red, finely pounded, together with two
pounds of pure lime and one pound of clarified honey, are —
added to each: when thefe ingredients have been well mixed
the fire is ftrengthened; and when the whole begins to boil
the dye is ftirred carefully round in all the veffels, that every
thing may be completely diffolved and mixed. After the
firft boiling the fire is flackened, and the dye is fuffered to
ftand over a gentle heat, while it is continually ftirred round :
this is continued even after the furnace is cooled, till a thick
feum arifes in the neck of each jar, and foon after difappears.

ue J

nant ae

to dye Blue, Yellow, or Green. 129

The dye is then allowed to ftand two day s, until the whole
is incorporated, and the dye thickens.

The dyers affert that with this dye they can produce three.
fhades of blue, and that, as the dyeing particles gradually
diminifh, they can dye alfo.a green colour by the addition’
of yellow.

When a manufafturer gives cotton yarn to a blue dyer,
he firft boils it at home in a ley of foda (4a/akar), then dries
it, wafhes it, and dries it again. The blue dyer lays this
yarn to fteep in pure water, preffes out the fuperfluous water
with the hands, and then immediately begins to dip it in
the blue jar, often wringing it till it is completely penetrated
by the dye. This firft tint is generally given to yarn in fuch
jars as have had their colouring matter partly exhaufted. It
is then dried, rinfed, and again dried ; after which, it is put
into the frefh blue dye, properly faturated; and, after the

- colour has been fufficiently heightened, it is dried for the laft

time.

For a yellow dye, the dyers of Aftracan employ partly
faw-wort, brought from Ruffia, and partly the leaves of the
kiflar belge or fumach. The procefs is as follows: The

_ yarn is firft boiled for an hour in a ftrong ley of /oda; it is

then dried, afterwards rinfed and Jaid wet to fteep for twelve
hours ina folution of alum with warm water. When it has
been dried in the air, it is laid to foak feveral times in
troughs with the dye which has been boiled thick in kettles
from the above-mentioned plants, till it has acquired the
wifhed-for colour, care being taken to dry it each time it is
foaked. It is then rinfed in running water, and dried for
the laft time. ;

On this yellow colour a green is often dyed. After the
yarn has been dyed yellow, it is given out to the blue dyer,
‘who immediately dips it in the blue jars, the dye of which
has been already partly exhaufted ; and if the green colour
is not then fufficiently high, the operation is repeated, the
‘yarn being dried each time. Roe
ve IV. O5-

148 a
. je
IV. Obfervations on a Junétion of the Red Sea to the Mediters
ranean. From the Journal de Phyfique for 1798.

Ir is needlefs to attempt to prove of how much import-
ance it would -be to form a junction between the Red Sea
and the Mediterranean. Every one is fenfible that it might
produce invaluable advantages in regard to the civilifation of
Afia and Africa; the reciprocal commerce both between
thefe two parts of the world, and between them and the
whole of Europe; and particularly in regard to France 3
efpecially when it fhall have joined the Mediterranean to
the German fea, as I propofed in 1786, when I i as
The Jun&tion of the Rhone with the Rhine.

It would be ufelefs alfo to examine every thing thas has
been faid by ancient hiftorians, refpecting the great works
that may have been executed, or only undertaken, for that
purpofe, by the kings and other fovereigns or governors of
Egypt, from Sefoftris or Pfammeticus down to Trajan or
Adrian, fince no traces or certain defcriptions of them

-are remaining; and fince fo many efforts made fo often,
and in fuch various ways, from time immemorial, only
ferve to prove the great importance that has always been
attached to this enterprife, even when it could have been
attended only with a local or very limited utility in compa-
rifon of what it holds out at prefent.

It is however certain, that an able engineer, by examining
the country with attention, would there difcover remains
fufficient to convey juft ideas refpecting the vague and con
tradi€tory accounis of the fituation, the direction, entrance,
and exit of thefe feveral canals. But all this would be of
little benefit. He would doubtlefs perceive, that if fome or a
part of thefe works have been effaced or deftroyed by the
hand of time, or abandoned on account of wars, or through
the policy or inftability of governments, none of them were
planned or executed in fuch a manner as to anfwer fully the

end

On a Junktion of the Red Sea with the Mediterranean. 129
end that ought to be propofed at prefent. They cannot,
therefore, be affumed as models or helps for any new work
of the fame kind; . which, however, as will here be feen;
could be executed with much ¢afe and fimplicity, fuppofing
the undertakers had entire and peaceable poffeffion of the
ifthmus and weftern coaft of the Arabic gulph, as well as
of the courfe of ihe Nile, and all the intermediate country
advancing a great way towards the fouth.

Without giving credit to a pretended higher level of the
Red Sea than of the Mediterranean, which is not pro-

‘bable, we muft, according to the account of all travellers,

admit there periodical tides and accidental elevations,
amounting from five to fifteen feet} and this is fufficient to
prevent every plan of a communication between thefe two
feas, conftructed on a perfect level, and always navigable
for the largeft veffels, fince an influx of waves fo great
would ravage it from the one end to the other, -and certainly
be followed by an ebbing fo low as to render the Mediterra-
nean higher and deftru@ive in its turn. But what would
oblige the undertakers to renounce this tafk is the impoffi-
bility of digging a long and continued bed, to the depth of
twenty feet below the level of the two adjacent feas, in a
diftri& which no doubt rifes much more above that level,
and which is faid to confift entirely of hills and downs of ex-

_ceedingly moveable fand, where the conftruction and pre-

fervation of a canal would be like the labour of Penelope.

We mutt not, therefore, think of joining thefe two feas but
by a fiver navigation for barks or boats drawing fix or eight
feet of water at moft, and between two ports, fuch as Suez
on the orie fide-and Grand Cairo, Foftat or Boulac on the
‘other, which feern to have been deftined for that purpofe,
fince their dire& diftance is only twenty-five leagues, and
finee the eaftern branch of the Nile below Cairo is as deep
as the fea itfelf at Damietta, Zan, &c.

But it is neceflary not only to give the new canal the leatt

length, but alfo the fmalleft elevation poffible, But accord.

F Nou. #2 K ing

140 On a Junétion of the Red Sea

ing to every account, the nature of the ground will oppofe
the full execution of thefe two objefts, and feems to fhow
that they might thwart each other. The only method
then is to weigh them both together, taking matters even in
the worft. light; and to determine the queftion I ns
the following preliminary confiderations :

1. The leaft elevation which the canal ought to have
from one end to another, fhould be equal to that of the
greateft tides or fwellings of which the Red Sea is fufceptible.
The level of the canal would be thus fixed, and all the dif-
ferences. from the higheft to the loweft rifing of the fea
would be counteraéted by one or two locks, as it might be
poflible to counteract at the other end all the overflowings
of the Nile, which probably rife higher, and which in that
cafe would require flood-gates.

2, There are two other methods which might be adopted
in the like cafe, but which would be far lefs advantageous.
One of thefe, which would fave the neceffity of locks both
towards the fea and towards the Nile, is, not to allow boats
or other veffels to come from or enter the fea but twice a day
at the times of the tides, and not to come from or enter the
Nile but when it is at its greateft heights. But this would
lay too great a reftraint on commerce, particularly at Cairo,
where the tranfportation of goods would not be poffible but
during two or three months: but ftill the level would be-
come doubtful and variable, like all tides and inundations ;
and there would neceffanly be alternate currents, which
would render the water brackifh and unhealthful, not only
in the canal, but alfo in the Lower Nile.

3. Fhe other method, in order to exclude locks alicia,
or at leaft.in part, would be; to deprefs more the bed and
level of the canal, taking care to guard it at each end by the
flood-gates, which would permit veffels to enter the fea or
the river at the times of their greatefi elevation. But, though
this method might render the courfe of the navigation freer
and lefs interrupted, it would not prevent the mixture of the

_ freth,

~
8
*

with the Mediterranean. 131
frefh and falt waters. It would fave nothing either in con-
ftructing or the labour of managing the locks: in thort, it
would increafe in a prodigious degree the folid content of
the excavations and the general expence of the works.

4. The fmalleft elevation which the canal ought to have
would be fixed then by the greateft height of the waters
either of the fea or the river. But in fuch an extent it is
probable that feveral eminences might oppofe this general
Teyel, and even in carrying the canal round thefe the labour
would undoubtedly be increafed. In fhort, it would be im-
poffidle to avoid the neceffity of making the canal begin ona
ridge or eminence; by which means it would defcend’ by
two inclined planes, one on the eaft towards the fea, and
the other on the weft towards the Nile.

5. In that cafe the queftion would be, to determine the
maximum and the place of the elevation, which could be
done only after a long examination of the fpot, and an exaé&
furvey of the higheft part of the ground, by means of le»
velling. The effential object of this examination will be,
1. To avoid both the fands which are to the north, and the
rocks or mountains that abound in the fouth. 2. To find

on the ridge of the latter that fpot which would correfpond
beft with the following conditions, viz. that the canal might

be rendered as fhort and as little expofed to windings as pof-
~ fible; and that its point of departure fhould be fo low that
veffels might afvend to it by the feweft poffible number of
locks, and yet give occafion to as little digging as poffible.
8. And as thefe three conditions will often be unattainable -
at the fame time, to balance them, and to make them reci-
procally give way and prevail in fuch a manner that the me-
dium may enfure the moft advantageous refult in the greatett
- number of refpedts.

6. Having thus determined the fummit or higheft point of
departure, with the length and depth of the canal, we may
eafily find; and without any doubt, the means of filling it,

K2 and

132 . On a Jonein of ihe Red a 4

and of feeding i it abundantly by the waters of the Nile, by
going up the’ river beyond Cairo as far as the {pot where i its
general height is greater than the level already fixed, and
from which it will be neceflary to draw off on the right bank
a lar ge {tream or branch of water, defended by ftrong gates
again ft muddy water or extraordinary inundations, and to
conduct it gradually in an inclination of fifteen or eighteen
lines in a hundred fathoms, and. to make it end by the
fhorteft paflage towards the weftern extremity of the point !
of departure. This, however, fuppofes that the mountains
fituated to the eaft cannot fupply water in fufficient abund-
ance and by a fhorter paflage, which would be extremely de-
firable, and which ought to be carefully examined ; for it
appears certain that the Nile has very little inclination below _
its cataraéts, which are nearly two hundred leagues from —
Cairo; and confequently the place where the water is drawn
off ought to be taken at a fufficient diftance to be higher
‘than the point of departure of the canal, however little it
may have been eftablithed above the level. of the higheft
tides and inundations.

4. According to the beft\ and lateft deferiptions of that
country, we may however believe that this point of departure
will neither require deep excavation below the furfaee of the
ground, nor a great elevation above the mouths of the canal,
either at the Nile or the Red Sea’; for it appears certain Ofi
the one hand, that the laft of all the ancient canals, that
afcribedto Amron the Arabian, was dug in a perfect level,
and even open from one end to the other, proceeding from
the Nileto’Foftat ; and on the other, that an ordinary rife of
16 cubits will be fuficient that the river may-enter there at
prefent, fora length of four leagues, traverfing Grand
Gairo. There is no reafon then to doubt that this rife
would proceed to the Red Sea, and would there make fome
fall, if the remains of the canal had not been filled up either’
by the hand of time, or by wars between thofe nations fepa-
_ rated. by the Adriatic, : ;

aS,

fider the impoffibility of conducting {9 far, and amidtt fuch
‘3A K3

with the Mediterranean. 133

8. Itis probable then that this grand communication might
be re-eltablithed by fimple cleanfing or by fome amendment,
but with fluices and other neceflary works at both the mouths,
that navigation might at all times be there poilible, what-
ever might be the variable height of the waters in the river
and the fea; the latter of which, notwithfianding what has
been faid on the fubject, will be found conitantly lower than
the former even at the time of the highe# tides. The high-

Fea rifings of the Nile, therefore, which at Foftat are faid to

be from 20 to 22 culits, muft determine the general level
of the canal, that is to fay, the height of the locks neceflary
to defcend towards each of its extremities when the waters
are at their loweft, and alfo the diftance and height of the
place from which the water of the Upper Nile muft be
drawn off to feed this canal, coating along the flope of
the mountain as far as the northern cape or promontory of

‘Mokattan, or from a bafon raifed about thirty feet above

Grand Cairo. It would alfo be attended with the valuable
advantage of fountains and great embellifhments to that city,
become the central mart or repofitory of the ancient world,
Befides, it would be a powerful prefervative againft infalu-
brity and that contagion which fo frequently afili& that im-

~menfe city, on account of the drought and exceftive filthi-

nefs which prevail there.

__Tt may be readily feen; then, that this plan does not prefent |

nearly fo many phyfical difficulties, and is not fuch an im-
menfe enterprife as fome have imagined ; fince the diftance
either from Cairo to Suez, or te Colzoum, or to any other
port more to the fouth or more convenient, does not exceed
25 leagues; for that of Suez feems dificult, and to be
threatened with being fpecdily choked up at the point of

the gulph which is the narroweft, and which becomes.

narrower every day—a new reafon for abandoning a canal,

‘though perhaps the fhorteft, which fhould proceed directly

from Suez to the Mediterranean, particularly when we.con-

a 7

a foil

‘

134 Experiments and Obfervations

a foil, aftream from the Nile, which however would be in-
difpenfibly neceflary to feed it, fince it ought hot, and even
could not be dug to the bottom, or to the level of the two
feas.

There is however one important remark ftill to be made,
which is, that the prefent trade of Egypt with Afia is carried
on merely by caravans, and by two diflerent ways; one en-
tirely over land acrofs the ifthmus and fands for 50 or 60
leagues, even to Syria; and another by a defile among the”
mountains of Upper Egypt, for 25 or 30 leagues only, from
Cophtos to Cofeir, which is a port of the Red Sea much
eafier,of accefs than Suez, becaufe the fea there is broader
and much lefs dangerous. But as this defile feems to be
favourable to.a canal, which might be fed equally well and
with more eafe from the Upper Nile, and as that river is
navigable to Cophtos as well as to Grand Cairo, there is’
every appearance that a canal in the latter fituation, planned _
with the fame care, would be more fure as well as more ad-
vaniageous to the nation that might have the fovereign pof-
feflion of Upper as well as Lower Egypt, efpecially as it is
abfolutely neceffary that it fhould be fufficiently powerful to
fubdue the Bedquins, who infeft the whole country, and
who would foon render the canal of Cairo as impracticable
as that of Cophtos,

V. Obfervations on the Organs of Vifion in’ Bats,
By M, SPALLANZANI

af YEP obfervations are extracted from a fmall work
publifhed by M. Spallanzani a few years*ago, under the
following title : ‘‘ An account of fome fpecies of bats, which,
when deprived of fight, perform their movements in the
air as if they ftill faw: a faculty not poffeffed by other birds
under the like cireumftances,” And the author fays that he
was led to them by fome experiments which he made on

night

on the Sight of Bats. 135

night birds. - He let loofe feveral birds ina chamber per-
fetly dark, and perceived that the bats flew about in it
without any impediment, and_neither rufhed againft any
thing in the apartment, nor touched the walls with their
wings. He at firft imagined that they were conduéted
by fome glimpfe of iight which he did not perceive, and on
that account he blindfolded them with a {mall and very
clofe hood. They then ceafed to fly; but he obferved at
the fame time, that this did not proceed from any depriva~
tion of light, but rather from the conftraint thence occa-
fioned, efpecially when a hood of a very light texture was

. attended with the fame effect.

He then conceived the idea of pafting up the eyes of the
bats with a few drops of fize or gum; but they ftill flew
about in the fame manner as if their eyes had been open.
As this however was not fufficient, he pafted up the eyes of _
thefe animals with round bits of leather, and this even did
not impede them in their flight,

That he might at length be certain of his object, he
blinded them entirely, either by burning the cornea with a
red hot wire, or by pulling out the pupil with a pair of fmall
pincers, and fcooping out the eye entirely. Not contented
even with this precaution, he covered the wounds with
pieces of leather, that the light might have no influence
whatever on the remains of the organs which had been de-
firoyed. ‘The animals feemed to fuffer very much by this
cruel operation ; but when they were compelled to ufe their
wings, either by day or by night, and even in an apartment
totally dark, they flew perfe€tly well, and with great caution,
towards the walls, in order to fufpend themfelves when they
wifhed to reft. They avoided every impediment great or
fmall, and flew from one apartment to another, backwards
and forwards, through the door by which they were con-
nected, without touching the frame with their wings. Ina
word, they, thewed themfelyes as bold and lively in their

K 4 flight

i % > le
3136 Experiments an Bats deprived of Sight.

flight as any other animals of the fame Species which enjoy
the ufe of their eye-fight.

M. Spallanzani ted the fame experiments with the res
refult on the eyes of the horfe-fhoe bat (vefpert. ferrum equi-
num), the dwarf-bat, the great bat (no@uia), and the bat of
Buffon. M. Spallanzani is convinced that the other four
fenfes fill remaining to thefe animals cannot fupply the -
want of fight; and he is therefore of opinion that a mew.
organ, perhaps a new fenfe, which is wanting in the human
Apecies, may in them be put in aGtivity by their being blind-
éd. Profeflor. Vafalli at Turin, Profeffor Roffi at Pifa,
M. Spadone at Bologna, and M. Jurine at Geneva, repeated
thefe experiments, and obferved the fame phenomena as ‘thofe
mentioned by Spallanzani.

VI. Experiments on Bats deprived of Sight by M. DE JURINE.
From the Journal de Phyfique for 1798.

Tue experiments of M. Jurine were made only on the.
Jong-eared bat (vefpertilio aurilus), and the horfe-fhoe bat
(vefpert. ferrum equinum). The bats-were procured from the
vaults under the fortifications of Geneva in the months of
December and January. The author firft obviates fome
doubts refpeéting the places where thefe animals refide in
é winter, as fome of them have been found j in a torpid ftate
in the trunks of old trees during that feafon,
The author obferves, that he found at the aboye feafon,
and 1 in the fame vaults, abundance of moths (phalene) and,
- crane-flies (tipude), and thinks he here difcovers oné of thofe
wife difpenfations of nature, by which other animals of more
utility find a fource of aliment when they could procure
nothing i in the atmofphere at that rigorous feafon.
The long-eared bat has fix incifive teeth in the under j jaw,
. three- lobed, and cut inta the form of a heart, The apps: has
four,

s

Experiments on Bats deprived of Sights — 437
four, and unequal. Theshorfe-fhoe bat has none in the up-
per jaw, except two fmall ones in the membrane of the pa-
_ Tate: the lower j jaw is furnifhed with four. When the horfe-

‘hoe bat attaches itfelf ta.a wall, it contracts its body, and
‘ wraps itfelf up in its fur in fuch a manner that it might be
taken for a black chryfalide. The long-eared bat appears
lefs careful of itfelf, and firft makes ufe of its hind feet, and
then of thofe before, in order to affix itfelf to a walk,

\ The temperature of the vaults which ferved them for a
habitation was between 50° and 57° Fahr. that of the exter-
nal air between 27° and 30°. M. Jurine having expofed fome
of thefe animals to a temperature between 36° and 39°,
feveral of them perifhed, and others fell into a fate of tor-
pidity ; from which he was not able to roufe them by any
touching, though a gentle current of air directed againft
them caufed them to make a movement, by drawing back
the whole body on the hind legs, and this they repeated as
often as the infufflation was renewed. M. Jurine had before
obferved the fame effe&t on mice. He remarked, however,
that the approach of a candle agitated and awakened them,
probably on account of the paection of the ambient air.
- A violent agitation of the air by which they are furrounded
makes them {peedily take wing.

: During the torpid ftate of thefe animals no movement
is obferved which can indicate that they breathe. A {mall
_ horfe-fhoe bat, a large bat of the fame fpecies, and a
long-eared bat were placed on a ftove, and exhibited
figns of life at different periods; but their infpiration
and expiration were extremely irregular, particularly thofe
of the long-eared bat. There is a ftriking difference be-
tween the-pofition of thefe two {pecies of bats when they fix
themfelves againtt any objeét. The horfe-fhoe bat hooks it-
felf all at once, with its head down and its legs upwards ;
while the long-eared bat turns itfelf round quiely, in order
to affume ‘ey often an oblique pofition,

‘ The

138 Experiments on Bats deprived of Sight...

The author then proceeds to the experiments which the
illuftrious Spallanzani undertook before, but in which great
fcope was {till left for the imagination. The author feems to
have found the defideratum which his predeceffor left for
thofe who might follow him in the fame path.

He extended in an apartment feveral willow twigs three
feet in length, at the diftance of fix inches from each other,
and let loofe two bats, which paffed and repaffed between
them, without touching them at all with their wings, and
which, when their flight was ended, always attached them-
felyes to the fame cornice, The author then cut out their
eyes; during which operation, the long-eared bat fuffered a
conifiderable hemorrhage from the ocular orbits. Being let
loofe in that ftate, they ftill flew to the fame interftices.

Thefe being barred up, they made choice of others, through -

which they pafled feveral times, always avoiding to touch
the twigs with their wings, and for that-purpofe they pafled
obliquely.

The long-eared bat fometimes ftretched out its neck,

and as it were made choice of that objeét to which it
withed to attach itfelf; a cuftom which it had before it was
blinded. It often applied one of its hind paws to its eye;
colleéted the liquid which exuded from it, and then applied
it with avidity to its mouth. Thefe two bats lived a long
time after they were deprived of fight. ‘Two long-eared bats,
the one blind, and the other haying the perfect ufe of its
fight, were let loofe together.. The blind one always fol-
lowed its companion, even obferving the fmalleft finuofities
of its courfe, The bat which faw, paffed between the twigs
with lefs dehcacy than the blind one.

M. Jurine then extended a net with large mefhes, after
making a breach in it. The long-eared batewhich faw,
paffed through it immediately; but the blind one ftopped
fhort, went all over the net, and, having found the breach,
pafled through without touching, it, and then foon joined its

com-~

}
q

Experiments on Bats deprived of Sight. 139

companion, which it afterwards followed wherever it flew.
Of what ufe then is fight to the bat, and what is the organ
that fupplies its place ?

_ The author then imagined that the folution of this pro-
blem could be found only by anatomical refearches. During
the courfe of thefe, he found the organ of hearing very great
in proportion to that of other animals, and a confiderable
nervous apparatus affigned to that part. The upper jaw alfe
is furnifhed with very large nerves, which are expanded in a
tiffue on the muzzle.

M. Jurine then extended his experiments to the organ of
hearing and that of fmell. Having put a {mall hood on a
long-eared bat, it immediately pulled it off, and flew. He
ftopped up its ears with cotton, but it freed itfelf in the like
manner from that inconvenience. He then put into its ears
a maftic of turpentine and wax. During the operation the
animal fhewed a great deal of impatience, and flew after-
wards very imperfectly.

A long-eared bat, the ears of which had been bound up,
flew very badly: but. this did not arife from any pain occa-
fioned by the ligature; for, when its ears were fewed up, it
flew exceeding well. In all probability the animal would
have preferred having its ears bound up to having them
fewed. Sometimes it flew towards the ceiling, extending its
muzzle before it fettled.

M. Jurine poured liquid pomatum into the ears of a bat
which enjoyed the ufe of its fight. It appeared to be much
affected by this operation; but when the fubftance was re-
moved, it took flight. Its ears were again filled, and its eyes
were taken out; but it flew then only in an irregular man-
ner, without any certain or fixed direction.

The ears of ahorfe-fhoe bat, which had the ufe of its fight,
were filled with ‘tinder mixed with water. It was uneafy
‘under the operation, and appeared afterwards, Teftlefs and
ftunned; but it conduéted itfelf tolerably well. On being
plinded, it ruthed with its head againft the ceiling, beat the

ozier

¥4o Experiments on Bats deprived of Sight. hae

- ozier twigs with its Wings, and made the air refound with
ftrokes which it gave itfelf pn the muzzle. This experiment .
was repeated on other bats with the like effects.

The tympanum of a large horfe-thoe bat was pierced with
@ pin (¢rois-quart). The animal appeared to fuffer much from
the operation, and: fell down in a perpendicular direétion
when thrown into the air. It died next morning. The fame
effet was produced on piercing the tympanum of a long-
eared bat with a needle, ~*~ ;

The author then made very aceurate refearches on the dif-
ference between the organifation of the brain of thefe two
kinds of bats, and, after a careful diffection, found that the
eye of the Iong-eared bat is much larger than that of the
horfe-fhoe bat, but that the optic nerve is proportioned to it.
The outer part of the ear of the former is much larger than
that of the latter, but the interior part is fmaller.

The horfe-fhoe bat is indemnified for this difference by a
greater extenfion of the organ of fmeil, as evidently appears
when the external elevations and irregularities of its muzzle
are examined. When it is about to take flight, it agitates
its nofe much more than the long-eared bat. —-

From thefe experiments the author concludes, firft, that
the eyes of the bat are not indifpenfibly neceflary to it for
finding its way; fecondly, that the organ of hearing appears
to fupply that of fight in the difcovery of bodies, and to fur-
nifh thefe aninials with different fenfations to direét their
flight, and enable them to avoid thofeyobftacles which may
prefent themfelves. The author alfo found on thefe animals
a particular kind of fleas.

VIE. On

“ca dam

VII. On the Antiquity and Advantages of Encauftic Painting,
with an Examination of the Proce[s employed in that Art by
the Ancients. From a Treatife entitled Antichita, Vantagoa,

-e Metodo della. Pittura Encaufta; Memoria del Ch, Sig.
Gioy. Fabbroni, &c. Roma, 1797. Quarto.

[Concluded from page 31 }

~

From what has been already faid, it appears that encau~
ftic paintingis much better calculated than oil painting to with-
ftand the power of time and the influence of thofe circum-
ftances which deftroy fooner any other kind. [ft affords this
advantage alfo to the painter, that he can lay on:an un-
changeable white, which cannot be ufed in oil painting, as
is proved by the fragment of a mummy above mentioned. |

We are indebted in particular to Nardi, Borrichivs, and
Jablonfki, for hints how to employ with advantage the
Egyptian remains of antiquity ; but one cannot help wonder-

ing, notwithftanding all the illuftrations of thefe learned

U

men, that they feem to be {fe little valued, and that mummies
are now almoft banifhed to apothecaries’ fhops, though they
are often monuments of feulpture on ‘account of the exterior
cafes in which they are preferved; .of painting, on account
of their clothing and bandages; and perhaps alfo of hiftory,
on account of the hicroglyphics which ferve on them as
inferiptions. In regard to the two firft circumftances, mum-
imies have not hitherto been fufficiently valued by thofe who

“neither trace out the progrefs of the human mirid, nor aré ©

intereftéd in-efiquiries refpefting the infancy ‘of the arts.
With regard to the laft point of fo much importance, wé
often hear people fay: Of what ufe is it to co!le& things of
which we underftand nothing? It may, however, be eafily
perceived that this is not the language of philofophy, whofe
penetrating eye fees farther, and which values every things.

~ Leibnitz confidered it impoffible to read and’ explain’ the

Etrufcan inferiptions ; he even doubted whether they were
6 charaéters,

142 On Encauftie Painting.

chara@ers, Without ftudying good collections and Etrufcars
monuments, could it have been poffible to difcover the
alphabet of thefe ancient people? Without the repeated re- ”
fearches of travellers, could it have been hoped that Barthe-
lemi would explain the Palmyrean infcriptions? Without
poffeffing and examining the prefent fragment, or fomething
of the like kind, could any one with certainty determine the

remote period when the art,of encauflic was praétifed, or

~

difcover the true method tn which it was employed? But
we fhall allow every one. to think on this fubject as he pleafes.
Our academy requires facts and obfervations: any thing elfe

does not merit its attention.

The firft fact, which I think I have proved, is, -that the
Egyptians were acquainted with and practifed wax painting. °

The fecend is the better prefervation of colours, and in
particular of the white, by means of encauftic, notwithftand-
ing the revolutions of many centuries.

The third is, that the matter of the Egyptian white colours
is not metallic calces or oxydes, whiclr at prefent are ufed
in oil painting.

And the fourth, a deduction from the experiments made
of the component parts of the ancient encauftic, which differ
very much from thofe already made known.

Thofe who are acquainted with the accuracy and certainty
of the method not Jong fince introduced into chemical ope-
rations, will be convinced that in 24 grains of the encauftic
painting, which [ ventured to detach from the above-men~
tioned Egyptian fragment, in order to fubjeét it to examina-
tion, the mixture of an hundredth part of a foreign fubftance
would have been difcovered with the greateft certainty ; that
the refin of Requeno mutt undoubtedly have been percepti-
ble to me, and that the alcali of Bachelier and Lorgna could
not have efcaped the counteracting medium. But in this
Egyptian encauitic I found nothing except very pure wax,
though I varied my analyfis in every known method. I muft ©
therefore conclude that modern learned writers, at Jeaftin —

refpett —

On Encauftic Painting. 143

_ tefpe&t to this Egyptian mode of painting, were as far from
the truth as the accounts of ancient authors appear to me
precife and fatisfa@tory; and that the encauftum with which
formerly the fore part of fhips and the walls of houfes and
temples were painted, was fomething different from foap or
refinous crayons (paffello di ma/iice).

The bafis however of the ancient pigments for the fkin
was perhaps formed of a waxy foap, with which they com-
bined lake (fuco) and white lead; and hence perhaps arofe
the well-known common expreffion, which is till figuratively
ufed, when people fay that a face has wona or cattiva cera,
according as the complexion appears healthful or fickly.
But as thofe who at prefent prepare paints for the fkin do not
ufe that oil which the portrait-painters employ, it is not im-
_probable that the ancients made ufe of one compofition for
paintings, and another for improving the natural complexion
of the female fkin. |

* Tam well aware that it will be afked: In what manner can
wax at prefent be rendered fufiiciently liquid for the ftrokes of
the pencil, if it be not converted into powder or foap? This
queftion, in my opinion, can be fully anfwered from the words
of an ancient author, and in the next place by experience.

Vitruvius in particular, book vii. chap. ix, expreffes him-
felf in the following clear manner :

* Thofe,” fays he, “ who wifh to retain cinnabar on
walls, cover it, when it has been well laid on and dried, with
Punic wax diluted in a little oil (let this be well remarked) ; -
and after they have fpread out the wax with a hair brufh,
they heat the wall by means of a brazier filled with burning
coals (hence it is called encauftic painting), and then make
it fmooth and level by rubbing it with wax tapers and clean
cloths, as is done when marble ftatues are covered with wax.
The effe& of this wax cruft is, that the colour isnot deftroyed
by the light of the fun or the moon.”

It here appears by thefe words of Vitruvius that the
Romans, who copied the Grecian procefs, which the latter

9 borrowed

14d “On Encanftic Painting.

borrowed from the Eg gyptians, mixed the wax with a att oif to
make it pliable under the bruth ; but no maftic, alkali or
honey, as has been ingenioufly imagined, and which fome
have thought might be employed with fuccefs. The difficulty
now will be confined to point out in what manner this oil
was employed. It does not appear that they ufed thofe fat
oils which are commonly called drying oils; becaufe they
could have employed thefe as we do, without the addition of
wax, which in fuch a cafe would have been entirely fuper-
fluous. Fat oils which do not dry would not have been pro-
per for that purpofe, as they would have kept the wax conti-
nually in the ftate of a foft pomade or falve. Befides, my

experiments would without doubt have fhewn me the exiftence °

of any oily matter.

With regard to effential or ie oils, a knowletlge of
' them is not allowed to the ancients, as the invention of dif-
tilling is not older than the eighth or ninth century, and
therefore falls in with the period of Geber or Avicenna.
But Herodotus fpeaks in a very clear manner of the diftilla-
tion of afphaltes, which was made at Sufa; and I, who difs
tinguifh fo much chemical knowledge among the Egyptians,
eannot fuppofe them ignorant of fo eafy a procefs. In the
temple of Vulcan at Memphis they had a fchool of chemiftry,
which flourifhed there for a long time, as we are told, by
Zofimus Panoplitanus, Eufebius, Sinefius, Albufaragius, &c.
Tn order to wfe wax in their encauftic painting, it 1s certain
that they muft have combined it with an ethereal volatile oil,
of which no traces fhould afterwards remain; becaufe this

was required for the folidity of the work, and’ becaufe: I~

actually found this to be the cafe in the fragment which I

examined. But though they might be unacquainted , with -

the art of feparating ethereal oils from the many fubftanses
which they contain, they certainly were acquainted with @
very volatile thin oil produced by nature, and which in vari+
ous places iffues from the earth, but probably not in Greece,

as I found reafon to conjecture from the following obferva~
tions + :

—_ ee

Gi Encauftic Painting. 145
tions. Strabo and Plutarch relate that the people of Ecba-
tana, in order that they might exhibit a pleafing {pedtacle to
Alexander the Great, fhewed him a flaming ftream, by
fprinkling rock-oil in the ftreets of a village, and then fetting
fire to it. They alfo rubbed over with naptha a naked boy,
and then fetting fire to it in the like manner caufed him to’
run about in a bath. Thefe people then were acquainted
with naptha, which ified from the earth in that diftrict +
bnt it was not known in Greece, at leaft to the common
people, as it never was feen by theny under the like cireum-
ftances. This ethereal oil was ufed, in my opinion, to
render wax fit for painting; and it is natural to fuppofe that
it would be firft employed for this ufe where it was firft
Enown. It appears to mé that the Greeks, ds was the cafe
with many other things, and as the above-quoted authors
fay, learned encavftic from the Egyptians, as the latter
léarned it perhaps from the Affyrians or Chaldeans. We
know that Lyfippus wrote exprefsly under one of his pic-
tures: Painted in encaulftic;’? which he,would not have
done, had-not this kind of painting been new er a fecret in
Greece.

Naptha is an‘etheredl oit ntuck lighter than fulphuric ether
rfelf, as I found, contrary to common opinion, by my ex-
periments. It is am exceedingly volatile oil, which entirely
flies off and evaporates without leaving’a firgle trace of it
behind. On account of this property naptha is ufed, as is
well known, to copy fignatures and manuferipts, by rubbing
it over the paper to which it may be requifite to transfer
any writing, as it makes it perfectly tranfparent. The paper
then becomes opake and white as before, after the naptha
has evaporated. Such'in al! probability was the cafe with
the oil, which Vitruvius does not fpecify, but which, as he
fays,; was combined with the wax. It was for this reafon
that I found no oil im the Egyptian wax painting when I ex-
amined it: We have therefore difcovered ths real mixttire
aled for the ancient encauttic painting.

Vor, T. | B Birt

146 On Encauftic Painting.

But, to bring my affertions to greater certainty, it was nie~
cei Tary not Ae to prove the abfence of every foreign matter
in the above-mentioned encaultic fragment by means of an
accurate analyfis, and to form fome conjecture what kind of
oil mutt haye been combined with the wax, but it was necef-
fary alfo to fearch for an imitation of it fynthetically; and I
had the good fortune to meet with a favourable opportunity
of gratifying ray wilhes im this refpect.

In the year 1785 my worthy fiend Gultenbrunn, an
eminent Saxon pater, now in London, refided at Florence.
{ prepared for him a foluticn of Venetian wax in highly
purified naptha, and defired him to mix up with it the
colours neceflary for a painting. -He immediately complied
with my requeft; and we were both aftonithed, as well as all
our friends, at the high tone which the colours affumed,
and the agreeable huftre which the painting afterwards ac-
quired, when it had been rubbed over with a foft cloth. I
abferved that, in following this, procefs, the artift can de-
termine the effect of the colours from their appearance on
the pallet. This is not the cafe when the wax is combined
with alkali, gum, or mattic, by which the pigments have a
different appearance under the pencil, from that which they
ought to have on the painting; beeaufe the painting, until it,
has been dried, heated, and varnifhed, appears muddy and
obfeure. At this period I had only conjecture in my favour
refpectne, the ecmpofition of encaufitec; but the. refult
of the above trial, and, {till more, my examination of the
Egyptian fragment, fo often mentioned already, freed me from
all doubt.

{ made another preparation of the like kind for that cele-
brated. painter Adee by combining a quantity of the
common fpirit of turpentine (acgua regia) with wax, the good
effect of which was alfo extolled by that artift. The pur-
pofe for which at prefent-I1 would apply a preparationof
this kind, is to daub over fome of thofe beautiful paintings in
frefco by Giovanni da San Giovanni, to be feem in the court

of

On Encauftic Painting. 147
of an elegant yilla near this city, which in my opinion
would certainly preferve them from that decay through
which they are advancing with rapid fteps to deftruction ;
for it appears from the words of Vitruvius, that encauftum
was ufed in the time of the Romans to cover parts which had
been already painted either with water colours or in frefco.
I judge, from the analogy of effeét, that.this was the fubftance
with which Apelles daubed over his paintings, and which,
according to Pliny, made them appear as if covered by a thin
plate of talc or tranfparent felenite, and gave the colours a
wonderful fofinefs. In the ancient cedar oil I can diftinguifh
only the more modern acgua ragia, or {pirit of turpentine ;
confequently that, or naptha, was the oily matter which the
ancient painters muft have ufed for their encauftic works.

As experiments made both by analyfis and combination
were favourable to my idea, I flatter myfelf that I have ap-
proached nearer the truth than the preceding celebrated
writers, whofe refearches were indeed highly ufcful and
meritorious, and among which the illuftrations of the
learned Requeno deferve much _praife. Should this be_
granted, I fhall think myfelf well rewarded for my trifling |
labour ; and nothing remains but to exprefs a fincere with
that I may fee the above method extended to all thofe pur-
pofes to which it was applied by the ancients, that is, to
preferve paintings in water colours, or on plafter, and
feulptured pieces of marble. Were our public ftatues covered
with encauftum, as was the cafe formerly, according to-
Vitruvius and Juvenal, the dark mofs (lichen) would not
adhere to their pores, which disfigures their whitenefs, and
renders them black; and to which the attra€ting of oxy-
gen by carbon may perhaps fomewhat contribute. Were
paintings @ fre/co and a tempera covered with wax in this
manner, Florence would not have loft fo many mafter-
pieces by Giovanni and Andyea, which it once poflefled.
Laftly, were this plaftic varnith ufed, after the method ‘of
Apelles, to give equality to the tone of the colours, and to

L2 preferve

143 Mr, Bentham’s Patent Method

preferve our oil-paintings, many valuable pieces would be
euarded from the deftruétive influence of the light and
atmofphere, which change every thing; infects would be pro=
teéted from being {potted with duft, which greatly mjure
their tints; and in particular we fhould prevent that damage
which the common refinous varnifhes oceafion, though with
flow fteps, as thefe varnifhes not only become black of them-
fslves with time, but, as they contract in drying, and; becoming
hard, they produce rents and cracks, and confequently bring
the painting, which it Ae withed to preferve, fooner to de-
firuction. ReGnous varnifhes are naturally {tif and’ un-
pliable, and the materials on which moft new paintings are
found are hygrometrie fubflances, which contract or expand
Jn proportion to the drynefs or moifture that prevails in the
atmofphere. If it be true, as Oberlin obferves, that the
yarnith (vernice di moricont) has rendered many beautiful
paintings fealy, which were taken. from the rains of Hercu-
Jancum in good: condition; what deftraétion muft it not
oceafion in paintings on. wood and canvas! Ginfeppe
Piazenza alfo makes a- very pathetic remark on this circum-
fiance. But 1 do not fay this with a view to offend thofe
jedicious and meritorious perfons who go to worls with pru-
dence and {kill, as - have no other object in: my obfervations,.
than to place in a, proper light the antiquity and {uperiority
of wax-painting.

—- pee aE

VIU. An Account of the “ New Method of performing and
facilitating the Bufine/s of divers manufaciuring and econo—
mical es avbich a Patent, dated 24th June 1795;
avas granted to “ SAMUEL Benruam, Eg. of Queen’s~
4 jnare, WVefiminfler”

ee IER firice the days cf Bacsn, the philofophers ef Europe:

have employed themfelyes in determining, by actual expe-
siments, the phy fical properties of matter, and the laws to
Ww hich

Se

eA ome

of performing divers Proceffis. 149
which it is fubjeét; not merely to gratify a harmlefs and
laudable curiofity, but with the avowed intention of reducing
to arational and folid fyftem of principles, the various arts,
manufactures, and economical procefles which, before that
period, depended almeft wholly upon chance or caprice.

To the refult of philofophical experiments we owe the
prefent advanced ftate of {cience, and the many improve-
ments which have been introduced into the manufactures cf
Britain, and have brought them to the high ftate of perfection
they have attained. Has Mr. Bentham, in the patent under
confideration, added to the number of pifyfical facts before
known? Has he difcovered any new principles to entitle
him, as a difcoverer, to enjoy for fourtcen years an exclufive
monopoly of the arts to which they apply? No fuch thing.
Mr. Bentham has difcovered what ail the world knew
before—what may be found, in various forms, feattered
through the pages of thoufands of volumes; irae that it
would very much promoie aris and manuf fa€tures, if means
could be devifed to enable us to apply, in the ane way, ali
the facts that have been determined by philofophical experi-
ment. Yes, reader, the learned of ali countries have been
indefatigable in their various purfuits for thefe laft two cen-
turies, only to furnifh materials for the exclufive advantage
and emolument of Mr. Bentham. But he fhali be allowed
to fpeak for himfelf.

Every one knows, that a patentee niufi lodge in the proper
office a {pecification, deferibing his invention in fo full
manner that, at the expiration of his term, the public may
be able to enjoy the benefit of the difcevery. The prefent
patentee, in compliance with this requifite, fays, ‘I the faid
Samuel Bentham do hereby declare, that my faid invention
is deferibed in manner following ; That is to fay, my inven -
tion confifts in the adea of applying to’ the ptirpofes of art
and manufacture, in the large way, the practice that has
been /o long in ufc, of extracting and excluding the aiy in
the way of philofoprigal experiment.” Te then proceeds to tell

L3 Ws,

we]

150 ; Mr. Bentham’s ‘Patent Method

us, that “air is either évozwn to be, or fufpected of being, an
obftacle to art and manufacture, in a great variety of ways 5’
but it would be infulting our readers to enumerate thofe he
points out, as they mutt be as well acquainted with them as _
Mr. Bentham himfelf. We fhall only obferve in paffing,
that, as he admits the fact to have been known before, it ap-
pears odd that he fhould call the zdea his invention.

He then proceeds to exemplify the ufes that may be
made of /zs invention, in preferving fubftances animal and
vegetable from putrefaction. It>was known, before Mr.
Bentham was born, that fuch fubftances might in fome de-
gree be preferved for a long time im vacuo: but perhaps
Mr. Bentham has found out fome new way of producing a
vacuum, and therefore is entitled to the exclufive ufe of that
method ?—No! He fays the air mutt be extracted from the
veffel or chamber by “ an atr-pump, or otherwi/e;”’ but the
other ways he has kept to himfelf. Mr, Bentham fuppofes
that, in the practice of potting folid fubftances, the fat, which
in a melted flate is thrown round them, acts “in good

mieafure’’ by excluding the air. It is partly true; but it
7 a) . A

performs another work which his vacuum would entirely
deftroy—it prevents the efcape of the juices.

“« Many of the changes,” fays the patentee, to which
bodies are fubject in pot of colour, are known to refult
from the action of the air. An exhaufted. chamber affords
the means of preferving them from all fuch changes, for any
length of time.’’ This, was known. long ago ; but we fhall
fuggeft one ule to which thofe may apply it, who fhall firft
purchafe permiffion from the patentee. Such as with to
preferve the colours of their clothes from being injured by
the a@ion of the air, may get an air tight-cafe made for
themfelves to walk inz-the bottom part terminating in a
pair ofboots. -After they have inclofed themfelves, let their

fervant, “¢ by an air-pump or otherwife,” extract the air,

“care being taken at the fame time to exclude the light,
when the prefencevof that element alfo is found to influence
f the

y:

‘nation ;*~. “ tranfmiffion and percolation :’

have glafs windows to it, but the glafs muft be thick.

of performing divers Proceffis. T51
the’ refult.” This procefs, excepting the boots, ‘has been
often tried, “ in the way of philofophical experiment,”
upon mice and other fimall animals; but, having never yet
been applied in ‘the large way,’ comes fairly within the
right of the patent. _

“ Diftillation;” *¢ effectuation of contact; “ intromif-
fion into tubular or other cavities,” (for inftance, filling a
thermometer, as if fuch a thing had never been performed in
the fame manner before Mr. B. hit upon the idea ;) “ impreg-

78: ?

«¢ mixture, viz.
of fluid mafies with powders, or heaps of fmall-fized bodies ;””

>

** regulation of heat;’’ and “ exficcation;” are all enume-
rated and exemplified at ereat length, as procefles in which
the exclufion of air would be an advantage: but we fhall
not abufe the patience of our readers by detailing the parti-
culars *.
** The vacuum chamber may be of the fize of a large
room :—to enable the operator to fee the procefles, it may
k ”
Indeed it muft! “ to enable it to refit the preffure of the at-
mofphere.”” * For the accomplifhment of fuch a variety of
purpofes,” fays Mr. B. “a variety of operations may refpec-
tively require to be performed; to fome of which,a variety
of machinery, and that more or lefs complicated,, may be
neceflary : as, in all or molt of thefe inftances, the fource of
motion will be expofed to the external atmofphere, while
the fubject to be operated upon will be in the vacuum
chamber, the moft commodious means of tranfmitting the
motion from. the one of thefe fituations will, on this account,
be an objeét of attention.’”’ Our readérs may furcly expect
fomething new in the way of invention after all this pompo-
fity. We are now told that “ the methods already in uje in
the way of experiment, fuch as the collar of leathers, will in

.* Thole who with to be informed more fully, may Tec a copy of .the
fpecificatign in The Repertory of Arts and Manufactures, vol. vil.

Lay general

~

152 “Mr. Bentham’s Patent, &c.

general be found fufficient, however large the feale! A
. {pindle fliding i in fuch a collar gives rectilinear motion ;’?

svonderful! <“ A fpindle turning round on its axis gives
circular motion ;’”’ wonderful!! From one or other of,
thefe two, or indeed from either of them, any other motions
may be produced at pleafure :’’—and if you cannot, from this
defeription, frame a parcel of Androides able to work in
your vacuum chamber, in packing beef and butter into
cafks, gilding and plating metals, cafting images, glueing

boards together, filling thermometers, ahd performing every

thing you can with, it is becaufe your fcull is a vacuum alfo:
Whoever can difcover the means, whether by an air-pump
or.otherwife, to make with facility fuch large vacuums, and
can contrive the jack 2 in the box who i is to brealie m the various
operations required, may do it without confulting with this
patentee, whofe invention confijis in an idea that fhould others
contrive fuch machinery, he ‘could prevent them from ufing
it without paying him for the privilege. It is however a
mittake, founded upon another, that what becomes an art
or manufacture ceafes to be philofophical ; ; when the faét-is;
that an art is only perfect in proportion as it is ftrictly fo.
He labours under another error, when he believes that the
difference in the fcale, on which any procefs may be carried
on, will furnifh grounds for a patent ! ! Great and fmail are
merely relative terms, and abfolutely mean nothing i in them-
felyes—1000 is a great number w hen compared with unity,
but when contrafted with 1,000,000 it becomes a fmall one.
~ The duty we owe to the public calls upon us to point out
the faults as well as the merits of Patent Inventions ; but
when we fee, as in the prefent inftance, an unjuft effort made
to monopolize ze the fruits of the accumulated fagacity of thofe
who Jabour for the benefit of their fellow-creatures in gene-
ral, it lays us under a double obligation to expofe the impu-
gence of i the’® canvas ;

IX, Q

* [ 753 j

EX. Onthe Theory of the Stru€ture of Cryflals, by the Abb? Hau,
From Vol. XVII. of ibe Annales de Chimie.

[Continued from Page 46.]
2. Various Examples of Decreafe on the Edges.

D ODECAEDRAL Sulphure of iron or martial pyrites
{ fig- 19, Plate VI.) Pyrites ferrugincujes-dod-ca:dres. Dau-
benton. Tad. Miner. edit, 1792, p.29, Del'Ifle, Cry/fallo-
graphic, t.i. p. 224. var. 16.

Geomet. Charaé. Inelination of any one of the pentagons,
fuch as DPRFS to the pentagon CP RGL, having the
Jame bafe P R 126’ 56! 3. Angles of the pentagon
CPRGL, L=1212 35’ 17"; Cor G=106? 35’ 541 30°";
P or R = 102° 36' 19’.

_ Lei us again conceive a cubic nucleus, the different edges
of which are fo many lines of departure to the fame number
of decrements, taking place at the fame time in two differ-
ent ways, that is to fay, by the fubtraction of two ranges
parallel to the edges AB, CD (fig. 7, Plate I1.*), and of
one range parallel to the edges AD, BC. Let us fuppofe
alfo that each lamina, being in thicknefs equal only to a
{mall cube of the fide A B and CD, is equal to double the
fide of AD and BC. This difpofition, in regard to the de-
crements proceeding from the lines DC, BC (fg. 7), is
reprefented by fg. 14. In this hypothefis it is evident that
on account of the more rapid decreafe in departing from
D Cor AB, than in departing from B C or A D, the faces
produced in the former cafe will be more inclined to the
plane A B C D, while the faces produced in the latter will
remain as it were behind; fo that the pyramid will np
longer be terminated by a fingle cube E.( fg. 12), which, on

* Allthe figures below 14 referred to in this article will be found in
plate Ii of the preceding number, and all above it in plates VI and VII of
the prefent number, :

account

154 Theory-of Cryflallifation. ©
account of its extreme minutenefs, appears to be only a point,

but by the range of cubes MN ST (fig. 14, Plate VI.)
which, fuppofing thefe cubes to be almoft infinitely fmall,

&

will prefent the appearance of a fimple ridge. By a necef-
fary confequence the pyramid will have for faces two trape-
ziums, fuch as D M N C, refulting from the firft decrement;
and two ifofceles triangles, fuch as C N B, which will be-
produced by the fecond decrement*.

Let us fuppofe, moreover, that, in regard to the lamine of
fuperpofition which arife on the face BC GH (fg. 7,
Plate II}, the decrements follow the fame laws, but by crofs
dire&tions ; fo that the more rapid of the two may take place
in proceeding from B C or G H towards the fummit of the
pyramid, and the flower in proceeding from C Gor B H
towards the fame fummiut. The pyramid refulting from
thefe decrements will be placed in a direiion oppofite to
that refting on AB CD, and will have the pofition exhi-
bited fig. 17, where it is feen that the edge K L, which ter-
minates the pyramid, inftead of being parallel to C D like
the edge M N (ig. 14 and 15), is, on the contrary, parallel
to BC. We thall then conceive what ought to be done in
order that the pyramid which will reft on D C G F (fig. 7)
may be turned -as reprefented jig. 16, and may have its ter-
minating edge P R parallel to C G (fig. 7). I fhall fay no-
thing of the pyramids that will reft on the three other faces
of the cube, becaufe it is evident that each of thefe pyra-
mids ought to ftand like that which arifes on the oppofite
face.

But as the decrements which produce the triangle C N B
(fig. 15) make a continuity with thofe from which refults the
trapezium C BK L (fig. 17), thefe two figures will be in
jhe fame plane, and will form a pentagon CNBKL ( fig. 18),

* Here the face which correfponds to A B C D ( fg. 7.) has 25 fquares

on each fide, as may be feen fg. 4. and the ftruéture of the pyramid in

gueftion may be imitated artificially by obferving the order and number of

Yor

the cubes reprefented in the fame figure!

Theory of Cryftallifation, 155
‘For the fame reafon the triangle D P C (fig. 16) will be on
a level with the trapezium DMN C (fg. 15) ; and by rea-
foning in’ the like manner in regard to the other pyramids,
it will be conceived, thai as the fix pyramids have for their
whole faces twelve trapeziums and twelve triangles, the fur-
face of the fecondary folid will be compofed of twelve penta-
gons, which will correfpond with the twelve rhombufes of
fic. 5; but with this difference, that they will have other
inclinations. This folid is reprefented alone jig. 19, and
with its cubic nucleus fig. 20, where it may be {een in what
manner it would be neceflary to proceed in order to extract
this nucleus. For example, if a fection be made pafiing
through the points D, C, G, F, you will detach the pyramid
refting on the face DC GF of the nucleus, which will by
this fection be uncovered. ‘

Among the cryftals belonging either to the fulphure of iron
(martial pyrites), or the arfeniate of cobalt (the arfenical co-
balt ore of Tunaberg), there is found a dodecaptron, the
faces of which are equal and fimilar pentagons, ‘and its nu-
cleus is a cube fituated as above defcribed. But there are
an infinite number of poffible dodecaedra, which may
haye, for faces, equal and fimilar pentagons, and will differ
from each other by the refpective inclinations of their faces.
Of all thefe dodecaedra, the one, the ftructure of which would
be fubjected to the before-mentioned laws, gives 126° 56’ 8”
as the angle made by the inclination of any two of its faces
DPRFS, CPRGL (fg. 19), at the edge of junction
P R, as may be eafily demonftrated by calculation*. But
though we cannot flatter ourfelves with the hope of attaining
to the precifion of feconds, nor even to that of minutes, in
meafuring the fame angle in dodecaedral pyrites, that mea-
furement taken with every poffible attention evidently ap-
proaches fo near to the refult given by calculation, that we
may confider that refult as ae real boundary of approxima-
tion, found by help of the inflrument, and conclude that

See Les Mémoires de l Academic des Sciences, année 178.
theo

rT;

-

156 Theory of Cryftallifation.

sheory has arrived at the utmoft point of accuracy. Whati
here fay takes place alfo in regard to all the other refults of
theory compared with thofe of calculation ; and it is obvious —
that if this theory were falfe, it would conduét to errors
which the inftrument would not fail to render fenfible, by
the great differences which it would give between the angles
found by calculation and thofe found by meafurement.

M. Verner and M. Romé de l’Ifle have confounded the
-dodecaedron of pyrites with the regular dodecaedron of geo-
metry, in which each pentagon has all its fides equal, and all
its angles equal aifo*. If thefe two celebrated mineralogifts
had made more ufe of geometry in confidering cryftals, they
would have perceived a very ftriking difference between thefe
two dodecaedra, fince the regular dodecaedron gives only
116? 33'54” as the inclination of its refpective pentagons,
which makes a difference of about 11° } between it and that
above mentioned. Nay, there is no law of decrement what-
ever capable of producing the regular dodecaedron, however
compound it may be imagined, as I have fhewn elfewhere +
in regard to a cubic nucleus, and as I can demonftrate at -
prefent, generally, for a nucleus of any form. After thefe
details it may be eafily feen how important the ufe of cal-
‘culation is, either to prove the truth of theory, or to trace
out the boundaries by which the progrefs of cryftailifation is
circumferibed.

We haye already then two kinds of dodecaedra; one,
whofe faces are rhombufes ; and another, whofe faces are
pentagons; produced upon a cubical nucleus, in confequence
of two fimple and regular laws of decrement, in a direétion
parallel to the edges of the nucleus, A multitude of new
polyedra, which will have the fame nucleus,’ may be con;
firuéted, by varying thefe laws in divers other ways.

* Tra‘té des Carad. des Foffiles, page 184. See alfo, La Cryftallographie.
ae M.de Ife, t. ti. p. 232 and, 233.

+ Mém.d: | Acad. des Sciences, année 1785, p. 223-

. Calcgreoys

Theory of Crpfallifatien. isf
Calcareous Metaftatic Spar (Fig. 21*).

Spath. calcaire 2 douze triangles. Daubenton. Tabl. Miners
édit. 1792, p. 15. nm. 5. De Pifle, Cryfiall. t. 1. p. 5305
var. 1.

Geomet.' Charaé. Inclination of the triangle o fd to of x,
To4° 28’ 40", and too bd, 144° 20! 26". Angles of the tri-
Bmeleey ds f= 101° 32/13"5 d = 54° 27° 30!" 7 0 == 24°
en Ey”.

Geomet. Properties. The obtufe angle o fd of each tri-
angle is equal to that of the rhombus of the pramitive form.

The inclination. of the faces 0 f d; of « is equal to that of
the rhombufes 5 afd, g af x (jig. 4), of the nucleust.

That part of the ax? of the dodecaedron which excéeds
on each fide the axis of the nucleus, is equal to that axis‘;
or, what amounts to the fame thing, the whole axis of the
dodecaedron is triple that of the nucleus.

The twelve fcalene triangles that compofe the furface of
this variety have their leffer fides, which are united two ts
two on the fix edges bd, df, fx, gx, gc, be (fig. 21), ex-
aGly fituated like thvfe marked with the fame letters 1A
Jig: 3 which gives an idéa of the’pofition of the’ nucleus in
regard to the fecondary cryfial.

It is thence feen that the lamine of fuperpofition decreafé
in a direétiori parallel to the inferior edges 6 d, df, fx, &e.
or the edges of which we have been fpeaking. The theo-
retic calculus demonftrates that this decreafing takes place
in two rariges of inteoral molecule ; and, as the lamine al-
Ways retain their rhomboidal firure, the fum of all their ex
ternal angles, analogous to J, d, f, «, g, c, produces. fix
longitudinal ridges, which form, alternately, the large and
mean fides o d, o f (fig. 21), of thé fcalene triangles. It

* This varicty is commonly called dent dz cochon. The Englith call it
dog" s tooth, dent de chien.

_ + The word metaflatic fignifies tranfpofition, or the metafta/fis of the an-—
U
gles of the nucleus to the fecondary cryftal.

R 5 may

7

other, will compofe the furface of a rhomboid analogous to |

458 . . Theory of Cryflallifation.

may readily be conceived that the Jaminz, at the fame time
that they decreafe towards their Iower edges, ought, on the
other hand, to increafe towards their fuperior edges, analo-
gous toa b, a f, ag, &c. (fig. 4.) in fuch a manner that |
the parts of the-cryftal fituated towards thefe edges fhould be
always enveloped, and that the angles at the fummits of the
thombufes fhould remain contiguous to the axis. But this
ts only an auxiliary variation, proper to fecond the effect of
the decreafe, which alone is fufficient to determine the form

of the dodecaedron.

Very obtufe Calcarcous Spar (Fig. 22).

‘Spath. calecaire rhomboidal tr’s cbtus. Daubenton. Tab. Mi-
mer. edit. 1792, p- 15, n°’. 2. De l’Ifle, Cryflall. t.1. p. 504.
war. 2.

Geomet. Charad. Inclination of the rhombus 2 a d b’to the

*ghombus @¢ if d’, 134° 25 36%. Angles of the rhombus

mad his.cor b= 114° 18) 56" 2 ord’ = 657 awe
This variety, commonly called /entzcular calcareous /par,
arifes from a decrement by a cae range on both fides of

the edges ah, ag, af ( fig. 23), and ec, e d, e x, contiguous
to the nits a, e, of the nucleus. An idea may be formed
of its ftructure by comparing it with that of the dodecaedron
whofe planes form rhombufes (fg. 5 and 12) originating
from the cube (fig. 7); and by fuppofing that the bates
inflead of decreafing at the fame time on all the edges, de-
ereafe only towards thofe contiguous, three by three, to the
angle C, and its oppofite. In that cafe the faces formed
will be redticed to fix, which, by prolonging themfelves ac-
cording to the law of continuity, fo as to interfect each

that in quefiion; except that it will have other angles on
account of the cubical form of its inteeral molecule:

From what I have bere faid it may be eafily Conceived
that the diagonals drawn from a to 4’ ( jig. 22), from @to 9’;
from ato f, &c. on the fecondary rhomboid, will be con-

: 6 founded

Theory of Cryftallifation. 159
founded with the edges a b, ag, af, &e. (fig. 23.) of the nu-
cleus, which ferve as lines of departure for the decrements.
Hence it follows, that to extraét this nucleus it will be ne-
ceflary to make the planes of the fections pafs along the dia-
gonals in queftion, as has been already remarked.

The Common Topaz (Rig. 25).

Rubis et Topaze du Brezil. WDaubenton. Tab. Miner. edit.
1792, p. 7, n°. I and 2.

The inclination of the trapezoid /r ¢m to the adjacent
plane rie y 136°; of the fame plane to & 7 % 1242 26! 3
of the plane ¢ m ge to m lig 93”.

The primitive form of ai topaz is that of a right qua-
drangular prifm 4 (fig.°24), the bafes of which are rhom-
bufes, having the angle 4 or r = 124° 26’. Theory fhews
that in regard to the integral molecula the height 4’ is to
the fide x x almoft in the ratio of 3 to 2.

The pyramidal .fummit of the topaz refults from a decre-
ment by two ranges of {mall prifms on the edges w r, rn,
nb, bx, of the fuperior bafe of the primitive form. The
planes tmge, lmge (fig. 25), on one fide, and bf Z Py
bud pon the other, arife from a decrement by three ranges
on cach fide of the edges nv, xg (fig. 24), which decre-
ment remains fulpended at a ae term, and leaves four
Tectangles¢ rye, kryw, lhcei,ubcd (fig. 25), parallel
to the planes of the primitive form. The effect of this decre-
“ment is reprefented fig. 26, where the rhombus 4 27 wv is the
fame as fig. 24; and all the fmall rhombufes by which it is

J fubdiyided, or which are exterior to it, reprefent the bafes of

- asmany molecule. The lines xd, x =, mi, n e, are dire@ted

to the law of decrement already pointed out, and
‘thelines cd, ci, yz, ye, an{wer to the planes of the prifm,
which are not fubject to this law.

pe: 3. Decrease on the Angles.
Othe GiBition which gave birth to the prefent theory,

: by
4

sae, ©

a

160 Theory of 3 Cryfallifation:
by pointing out the pofition of the rhomboidal nucleus in-
clofed in the regular hexaedral prifm of the calcareous fpar,
was not fufficient to conduét imn nediately to a determination
of the Jaws of thofe decrements which’ produce fecondary
cryftals. It was neceliary to pals thr rough intermediate fteps
tmore fimple than the refirlt of thefe laws in regard to the
pufm in gueftiom. I fhall now proceed to give an idea of
thefe laft refults, which depend on laws of decrements whofe
Tines of departure are hot parallel to the edges of the prifii-
tive form, but to the diagonals of its faces.

To affitt the iinagination in conceiving the method which
t have followed to inveftigate thefe new decrements, I {half
remark, that the fame fubffances which exhibit the dodecae-
dron with pe cntagonal planes originating from the cube
( fig. 19 and 20), and which might even affume the form of
the dodecaedron w bo! fe planes aré rhombufes (fig. 5 and 6),
are found alfo under that of the reeular oftaedron. But it
appears, on the firft view, fhat i might be poffible to bring’
the ftructire of this cctaedron’ to a decrémnent on the edges
of a cube; for, if we confine curfelves fo make the lamina
of fuperpofiaion ceereafe’ only on the edges of thé two oppo-
fite faces of this cube, for cxainple, on’ thofe of the fuperior
bafe A B C D (fig. 6), and of the inférior bafé, we fhalf
have in general two pyramids applied on thefe bafes; and
if we fuppofe further that the faces of thefe pyramids are
éxtended until they meet, which is nothing elfe than conti-
nuing the effect of the law of decrements in thé {pace fit
ated between the bafes of the cubé, we {hall arrive af an oc-
facdron, the angles of which will vary according as the law
fhall determine a greater or fmaller number of ranges fab-
tracted. But theory demonflrates that there’is no law,
howeve? complicated it may be fuppofed, which is capablé
of givirig equilateral triangles as the faces of this 6@aedron.

On the other hand, if we divide a regular o€taedron, ori-
ginating from a cube, we fhall perceive that the cubic nu-.
élous is Situated im this oGtaedion in fuch a manner that cach ©

- of

Theory of Cryftallifation: 161
6f its fix folid angles correfponds to the centre of one of the
faces of the oGtaedron, which could not be the cafe on the
hypothefis of a decrement on the edges. From this relation
of pofition, added to the impoffibility of applying here the
theoretic calculus, I have concluded that the law of decre-
ments accomplithes its end, in fuch cafes, by a progtefs differ-
ent from that which conduéts to the forms before deferibed ;
and my refearches, in regard to that point, have unfolded a
new order of faéts which add much to the fecundity of eryf-
tallifation, and at the fame time to that of its theory. But
on this fubjec it is neceflary to enter into a more particular
inveftigation.

Let AB C D (fig. 27) be the fuperior or inferior furface
ofa lamina compofed of fmall cubes, the bafes of which are
teprefented by the fquares. that fub-divide the whole fquare.
If we confider the feries of cubes to which the fquares a, 3, c,
d, ¢, f, g, ; 2, belong, it is evident that all thefe cubes will be
on the diagonal drawn from A to C, and that they will form
one ftring (fig. 28), which will not differ from the ftting of
the cubes a, », 9, 7',5', ty w', ws 2's (fig. 27) lying in the
dire&tion of the edge AD; except in this, that in the former
the cubes touch only by one of their edges, and in the lat-
ter by one of their faces. We fhall obferve at the fame
time, throughout the whole extent of the lamina, ftrings of

cubes parallel to the diagonal, one of which is pointed out by

the feries of letters 9, v, 2, #, x, Jy % another by that of the
letters 7, #, 2, m, p; 0, 7, 8, and fo of the reft.

We may conceive then that the lamine of fuperpofition,
inftead of projeéting beyond each other one or more ranges
of cubes, in a dire€tion parallel to the edge, projet beyond

_ each other in a direttion parallel to the diagonal} and we

*’

fhall conftru& in the like manner around the cubic nucleus
folids of different figures, by placing, fucceffively, above

‘the different faces of this micleus, laminz, which may arife

in the form of pyramids, and which willexperience the kind

‘of decrement juft deferibed. The faces of thefe folids will

Vou. I, M net

162 Theory of Cryftallifation.

not be fimply furrowed by ftrize, as when the lamina de«
creafe towards the ridges. They will be roughened by am
infinite number of falient angles, formed by the exteriot
points of the compofing cubes, which is a neceffary confe-
quence of the continually angular figure prefented by the
edges of the lamin of fuperpofition. But all thefe points
being fituated on a level, we may fuppofe the cubes fo fmall
that the faces of the folid will appear to form fo many {mooth
and continued planes.

But this will be rendered more ftriking by an example.
Let it be propofed: to conftru€&t around the cube AB GF
(fig. 29), confidered as nucleus, a fecondary folid, in which
the lamina of fuperpofition {hall decreafe on all: fides by a
fingle range of cubes, but im a direétion parallel to the dia-
gonals. Let ABCD (fig. 30), the fuperior bafe of the
nucleus, be fub-divided into 81 fmall- fquares, reprefentiny
the exterior faces of as many molecule. What will be faid
in regard to that bafe may be applied to the other five faces
of the cube.

Figure 31 reprefents the fuperior furface of the firft la-
mina of fuperpofition, which ought to’ be placed above
ABCD (fg. 30°), in fuch a manner that the point @’ may
anfwer to the point a, the point 4’ to the point: 4, the point
¢’ to the point c, and the point d’ to:the point d. _It-may be
readily feen by this difpofition that the fquares A a, Bb, Ce,y.
Dd, (fig. 30), remain-uncovered, which will fulfil the law
of decrement abovedefcribed. It is moreover feen that the
borders QV, ON, LL, GF, (fig. 31),-project by one range”
beyond the borders AB, AD, CD, BC, (fig. 29), which
is neceflary, that the nucleus may be enyeloped towards thefe-

edoees. For a little attention will fhew, that if this were
o a |

not the cafe, that is to fay, if the edges of thte lamina repre-
fented fig. 31 as well as the following, coincided with the
lines ST, EZ, ¥Y X, M U, on which fuppofition they would.
be on a level with AD, AB, CD, BC, (fig. 30), they
would form.re-entering angles towards the analogous parts

- of.

Theory of Cryftallifation. 163
éf the éryftal. Thas im the lamirie applied on ABCD
(fig. 29), all the edges anfwering to CD would be on a le-
vel with C DFG; of which they would fornt a prolonga-
tion; and in the lamine applied on D C GF all the edges
analogous to the fame ridge C D would be on a level with
ABCD, from which there would neceffartly refult a re-en-
tering angle eppofite to the falient angle formed by the two
faces ABCD and CDFG: But the re-entering. angles
appear to be excluded by the laws which dehesie the
formation of fimple cryftals:; Fhe folid will increafe then
in thofe parts to which the decrement does not extend.
But as this decrement is alone fufficient to determine the
form of the fecondary cryftal, we may fet afide all the other
variations which intervene only in a fubfidiary manner, ex-
cept when it is withed, as in the prefent cafe, to conftruct,
artificially, a folid reprefentation of a cryftal, and to exhibit
all the details which relate to, its ftructure.

The fuperior face of the fecond lamina will be like
me, G5 LK Gye, 32), and this lamina-mutt be placed
above the emda in {uch a manner that the points a”, b,

"d's may anfwer to the points a’, B, c’, d's (fige 31),
which will leave uncovered the fquares that have their |
exterior angles fituated in Q, S, E, O, V, T; M; G; &e.
and coritinue to effect the decrement by one range. Itis
here feen that the folid increafes fucceffively towards the
analogous edges at AB, BC; CD, AD (fig. 30), fince be-
tween A’ and L/; for example, (.fig. 32), there are thirteen
fquares, whereas there are only eleven between Q V and L I
(fig: 31): But as the effet of the decrement contracts
more and more thie furface of the Jaminz in the direction of
the diagonals, nothing is neceflary but to add towards
the edges that do not decreafe, a fingle cabe denoted by
A’, G’, L’ or Ky (fig. 32); inftead of the five which termi-
hate the preceding lamina along the lines QV, GF, LI;
ON, (fg. 31).

The large faces of the Jamine of fuperpofition, which hi-
thierto were oflagons, QVGFILNO, (fg. 31), having

M » arrived

164 Theory of Cryftallifation.

arrived at the figure of the fquare A’ G’L! K’ ( fig. 92)*,
will, when they pafs that term, decreafe on all fides at the
fame time, fo that the following Jamina will have for i its fue
perior face the fquare B’ M'I’S’ (fig. 33), lefs by one range
in every dire€&tion than the fquare A‘’G’ L’K’ (fig. 32):
This fqaare muft be difpofed above the preceding in fuch
a manner that the points c’, 7’, 2’, b’, (fig. 33), may corre-
fpond with the points c, f, g, 5 (fig. 32)-

Figures 34, 35, 36 and 37 reprefent the four lamina
which ought to rife fucceffively above the preceding, under
this condition, that the fame letters muft correfpond as
above. The laft lamina will be reduced to a fingle cube,
diftinguifhed by 2’ (fig. 38), and which ought to reft upon
that pointed out by the fame letter fig. 37.

It follows from what has been faid, that the lamin of fu-
perpofition applied on the bafe ABCD (fig. 29 and 30)
produce by the total of their decreafing edges four faces,
which, im proceeding from the poimts A, B, C, D, incline
one to another in the form of a pyramidal fummit.

It is here to be remarked, that the edges in queftion have
Jengths which ‘begin by increafing, ‘as may be feen on in-
_fpecting fig. 31 and 32, and which then proceed decreafing,
as may be fecn by the following figures. It thence refults
‘that the faces produced by the fame edges increafe at firft,
‘and afterwards decreafe in breadth, fo that they become
quadrilaterals. Figure 39 reprefents one of thefe quadrila-
‘térals, in which the inferior angle C is confounded with the
‘angle C'( fig. 29) of the nucleus; and the diagonal L @
‘reprefents the edge L."G' of the lamina A’ G’ L/ K’ ( fig. 32),
which is the moft extended in the direétion of that edge.
Andas the number of the lamine of fuperpofition which pro- -
duce the triangle LCQ ( fig. 39) is lefs than that of the laminz
which produce the triangle LZQ, fince there is here only one

* In the prefent cafe this figure takes place from the fecond lamina of.
fuperpofition, By affuming a nucleus compofed of a greater number of
molecule, it is evident that we fhould have a more remote boundary.

5 lamina

Theory of Cryftallifations 163
lamina preceding the lamina A’ G’ LK’ ( fig. 32), while there
are fix which follow it as far as the cube z (fg. 38) inclufive-
ly, the triangle LZQ (fig. 39), compofed of the fum of
the edges of thefe latter laminz, will have a much greater
height than the inferior triangle LC Q, as exprefled in the
figure.

The furface of the fecondary felid will be formed then of
24 quadrilaterals, difpofed three and three around each folid
angle of the nucleus. But in confequence of the decrement
by one range, the three quadrilaterals which belong to each’
folid angle, fuch as C (fig. 29), will be in the fame plane,
and will form an equilateral triangle ZIN (fig. 40). The
twenty-four quadrilaterals then will produce eight equilateral
triangles, one of which is reprefented fig. 41, in fuch a
manner as to fhew, on a fimple view, the affortment of
the cubes that concur to formit; and the fecondary folid
will be a regular oftaedron. Figure 42 fhews this octaedron
in which the cubic nucleus is inclofed, fo that each of its
folid angles C, D, F, G, &c. eorrefponds to the centre of one
of the triangles IZN, IPN, PIS, SIZ, &c. of the
octaedron. It may be readily feen, that to extra this nu-
cleus, it would be neceffary to divide the oftaedron in its
eight folid angles, by fections parallel to the oppofite edges,
For example, the fetion made in the angle Z ought to be
parallel to the edges IS, IN, TN, TS; and hence will re-
fult a fquare which will itfelf be fituated parallel to the
fuperior bafe ABCD of the nucleus, and which will be
confounded with that bafe when the feétions have made the
faces of the oétaedron to difappear entirely.

This ftru€ture is that of the octaedral fulphure of lead
(galena), and the muriate of foda (common isit) of the fame
form.

I call decrements on the angles, thofe which take place in
a dire¢tion parallel to the diagonals, as in the example jut
mentioned. This denomination will fupply us with the
means of exprefling in a precife manner the refult of each

M 3 decrement,

266 Theory of Cryftallifation,

decrement, by pointing ont the angle which ferves j it as 4
point of departure.

Other Examples of Decrements on the Angles.
; Acute calcareous Spar (fig. 43)..

Spatb calcaire rbomboidal aigu. Daubenton, Tab. Miner,
edit. 1792, p.15.n°, 3.. Spath calcaire muriatique. De VIfle
Chryftallographie, t. ° p. 520. var. 12,

Geomet. Charaét. Inclination of pxry to pu oy 78° 297°
47” and to ty %s 1O1"39!13”, Angles of the rhombus
P2ry, ? or 575° St 20"; 2 Ory = 104° 28°40", | In-
clination of the oblique diagonal drawn from ptor with the
edge pu, 71° 33’ 54”.

Geomet, Propert. The angles of the rhombus are equal to
the refpeétive inclinations of the faces of the nucleus, and
reciprocally.

The angles of the principal quadrilateral, or that which
paffes through two oppofite oblique diagonals fr, wz, and
through the intermediate edges pu, ir, are the fame as on
the nucleus.

To conceive the ftructure of this rhomboid, let us fuppofe
that ab df (fig. 44) reprefents the face of the nucleus
marked by the fame letters (jig. 4), fubdivided into a multi-
tude of partial rhombufes, which are the exterior faces of fo

‘many molecule. Let us fuppofe farther, that the laminz of
fuperpofition, applied on this face, decreafe by one range
towards the lateral angles ab d, a f din fuch a manner that,
on the firft the two rhombufes 64 & 7, fm in are uncover-
ed, that on the fecond the uncoy ered rhombufes are thofe
traverfed by the diagonals C0, uy, On the third thofe traverfed
by the diagonals s ¢, gz, &c. in which cafe the decreafing
edges will fucceffively correfpond with thefe diagonals.
This law of decrement will produce two faces, which pro-
ceeding from the angles }, fwill rife in the form of a roof
above the rhombus a 4 df, and will meet on a common edge
fituated immediately above the diagonal a d, and which will

be

Theory of. Cryfallifations. 157,

‘he parallel.to.it ; and as there are fix rhombufes that undergo
like decrements on the primitiye form, the faces produced
will. be twelye an number. But in virtue of the law of de-
creafe by one range, the two faces which haye the fame
angle, 4,.f,.¢, &c. (fig- 4), for the point of departure, will
be in the fame plane, which reduces the twelve faces to fix,
and transforms the fecondary cryftal into an acute rhomboid
£2 (fg: 43):

This rhomboid, from what has been faid, has its edges,
p% py, pu, fituated each as the oblique diagonals of the
nucleus, or thofe which would be drawn from a to d, from
a to x, from a tore, &c. (fig. 4).

The edges of the laminz of fuperpofition experience, in the
parts to which the decrement does not extend, auxiliary ya-
rations, in virtue of which they are prolonged to envelop the
nucleus towards thefe parts, as in the regular oétaedron, the
firucture of which has been already explained. Moreover,
while the lamine decreafe, for example on the angles afd,
af x, (fig. 4), they undergo alfo towards the adjacent angle
df x, variations which intervene in a fubfidiary manner to aid
the effect of the principal decrement. The variations here are
alfo decrements by a fimple range on the inferior angles. But
in cafe the principal decrement fhould proceed by two ranges,
three ranges, or a much greater number, thefe variations
would become decrements of a particular nature, and which
would not be parallel to the diagonals.

In fhort, we might apply here what we have already faid
in regard to the firft variations confidered oft the regular
oftaedron, and obferve, that the principal decrement alone
determines the form of the fecondary cryftal; fo that this de-
crement being well comprehended, nothing is then neceffary
but to fuppofe its effect prolonged, in order that the faces to
which it gives birth may interfeét each other in fuch a
manner as to circumfcribe entirely the fpace to which they
correfpond,

M. Bournon has difcovered beautiful cryftals of this

M4. variety

168 . Theory of Cryftallifation.

variety at Coufon near Lyons. It is obferved alfo in fmall
yellowith cryftals, often thrown together in confufed groups

in the calcareous banks near Paris. The freeftone (lapis

arenarius) of -Fontainbleau, which is nothing elfe than

calcareous fpar accidentally mixed with quartzy particles,

exhibits the fame form. The cryftals of this ftone yield to

the mechanical divifion; and have their natural joinings, like

thofe of the cryftals of pure fpar, fituated in the planes.
parallel to the edges p=, py, pu, &c. (fig. 43), and which

would pafs at an equal diitance from thefe edges.

Rhomboidal Iron Ore (fig. 45).

Mine de fer lenticulaire. Daubenton, Tab. Miner, edit.
179%. Pp. 30, n°. 3.

Geomet. Chara. Inclination of BCRP to BCOA or
OCRS, 146° 26’ 33”; Angles of the rhombus BCRP,
Cor P= 397° 9! 9! Bor Rh = 02° 57 BY «

The lamine which compofe this rhomboid decreafe by
two ranges on the angles bcr, ocr, bco, &c. (fig. 45),
which concur to the formation of the two folid angles ¢, x,
of a cubic nucleus. The faces produced, inftead of being on
a level, three and three, around thefe angles, <g in the cale
of a decrement by a fingle range, incline one to the other,
and extend above the faces of the nucleus in fuch a manner
that their diagonals are parallel to the horizontal diagonals
of the fame faces,

By this it is feen that the cube here anfwers the purpofe
of a rhomboid, which fhould have its fummits in ¢ and 2, in
which cafe there would be only one axis pafling through the
fummits in queftion. In the dodecaedron, on the other
hand, with pentagonal planes (fig. 19), the cube performs
the functions of a reétangular parallelopipedon, and then
we may conceive three different axes, each of which ‘paffes
through the middle of the two oppofite faces. I have
ebferved that when: the cube began to perform the one or

: ; other

Method of deftroying Infeés. 169
other function, in regard to one fpecies of mineral, it con-
tinued that funtion in all the varieties of that {pecies.

The cryftals of rhomboidal iron are found among thofe
of the iron ore of the ifland of Elba. But it is very uncom-
' mon for the law of decrement to attain to its boundary, and
for the rhomboid not to be modified by facets parallel to the
faces of the nucleus,

If the decrement which produces the rhomboid took place
at the fame time on the eight folid angles of the cube, there
would refult from it a polyedron of 24 facets, all like the |
trapezoidal granite, of which I fhall fpeak hereafter, but
with a very different ftructure. This refult is realifed by na-
ture in the cryftals found at the Calton-hill near Edinburgh,
which are confidered as zeolites.

[To be continued. ]

X. Method to deftroy or drive away Earth-worms and various
other Infeéts hurtful to Fields and Gardens, by M. Soco-
LOFF. From the New Tranfaétions of the Imperial Aca-
demy of Sciences at Peterfburgh, Vol. V.

"Tuoucs it is certain that earth-worms occafion great
deftruGtion by gnawing the tender roots of fhrubs and planis,
and that other infects, fuch as caterpillars and locufts, are
exceedingly hurtful both to fields and gardens, few have
given themfelves the trouble to devife any remedy for this’
evil. I flatter myfelf, therefore, that I fhall do a fervice to .
the public if I point out an eafy and fure method, certified by
experience, of either killing or driving away from fields and
ardens all noxious vermin.
As the deftructive power of quick-lime, heightened by a
fixed alkali, which corrodes, diffolves and defiroys all the
tender parts of animals, has been long known, I thought
bis mixture would be the beft means for accomplifhing the
object T had in view. I took three parts, therefore, of quick-

lime

170 Method of deftroying Infeéts.

lime, newly made, and two parts of a faturated folution of.
fixed alkali in water, and thence obtained a fomewhat milky.
liquor fufficiently cautftic, highly hoftile and poifonous to
earth-worms and other fmall animals ; for, as foon as it.
touched any part of their bodies, it occafioned 1 in them vio-
lent fymptoms of great uneafinefs. If this liquor be poured
into thofe holes in which the earth-worms refide under
ground, they immediately throw themfelves out as if driven
by fome force; and, after various contortions, either lan-
guith or die. If the leaves of plants or fruit-trees, fre-
quented by the voracious caterpillars, which are fo deftruc-
tive to them, be fprinkled-over with this liquor, thefe infects
fuddenly contraét their bodies and drop to the ground. For
though nature has defended them tolerably well hy their
hairy {kins from any thing that might injure their delicate
bodies, yet, as foon as they touch with their feet or mouths
leaves which have been moiftened by this liquor, they be-
come as it were ftupefied, inftantly contract themfelves, and
fall down.

Thad not an opportunity of trying a like experiment on
locufts: yet we may conclude, and not without probability,
from their nature, and the general deftructive qualities of
the above liquor, that they, in the like manner, may be
driven from corn-fields, if it be poffible to fprinkle the corn
with the liquor by means of a machine:

With regard to plants or corn, thefe fuftain no injury from
the liquor, becaufe it has no power over the productions of
the vegetable kingdom, as I have fully learned from expe-
rience; or, if any hurt is to be fufpected, all the danger will
be removed by the firft fhower that falls. This liquor may
be procured in abundance in every place where lime is burnt, |
If the lime be freth, one part of it infused in about feventy
parts of common water will produce real Jime-water. The
want of the fixed alkali may be fupplied by boiling wood-.
afhes in water, and thickening the lye by evaporation.

This liquor might be employed alfo to kill. bugs and other:

domeftig

On the Revivification of Infe&ts. 17
domeftic infects which are noxious and troublefome; but,
on account of its ftrong lixivious fmell, which difpofes the
human body to putridity, I dare not recommend the ufe of it
in houfes that are inhabited. Befides, bugs may be eafily
got rid of, as I have repeatedly found from experience, by
the oily pickle that remains in cafks in which falted herrings
have been packed. To this liquor they have a ftrong aver-
fion ; and, if they are moiftened with it, they dje in a very
fhort time,

XI. On the Revivification of fome Kinds of Infeéts killed in
Spirit of Wine. By M. Socororr. From the New

Tranfactions of the Imperial Academy of Sciences at Pe-
terfburgh, Vol. V,

Ir is very fingular, and worthy of great attention, that a
fmall infe&t intoxicated with fpirit of wine and then im-
merfed in it, or killed on purpofe in that manner, may, by
certain means, be revivified, after having been deprived of
all figns of life for about a quarter of an hour. I had occa-
fion to obferve this cireumftance, for the firft time, in com-
mon flies ; for itis well known that thefe infects are ftrongly
attracted by the fmell of fpirit of wine; and that, becoming
intoxicated by it, they fall into the liquor, and are drowned.
Having thrown a great number of flies which had pre-
rifhed in this manner in a glafs, into a ftove among wood
afhes fearcely warm, and looking into the ftove a little while
after, on account of fome experiments I was making, I ob-
feryed, not without aftonifhment, the flies ftart up from the
_afhes, and, after wiping themfelves clean from the duft ad-
hering to their wings, fly away as if nothing had happened
to them*.
My

* A circumftance of a fimilar kind occurred to the late Dr. Franklin.
While he reGided in F rance he received from America a quantity of Ma-
dcira

Yb On the Revivification of Infeéts.

My curiofity being excited by this circumftance, TI left a
wide-mouthed glafs, into which I had put fome fpirit of wine,
uncovered, on purpofe, and, having colle&ted the flies which:
J afterwards found dead in it, I buried them carefully among
the before-mentioned wood-afhes; and ma little time, when
the moifture of the fpirit had been completely abforbed by
the afhes, I obferved them all revivified. Being convinced
in this manner that the experiment would fucceed with com-
mon flies, I refolved to make a like trial with other kinds of
infects. I therefore took fome fmall beetles, which were
thofe neareft at hand, put them into a glafs filled with fpirit
of wine, and, when they were perfeétly dead, covered them
with afhes. Thefe, to my great fatisfaction, were reftored
to life in the like manner. ,

I made an experiment alfo with a {mall fpider and a young
moth, by depriving them of life five different times within
the courfe of three hours, and always with the wifhed-for
fuccefs, except that the fpider, after the laft experiment,
was become fo languid and weak that it could fearcely
crawl. I found the like effeét to be produced on bugs, only
that it was neceflary to keep them longer in the afhes before
they were brought to life.

In regard to butterflies I cannot {peak with certainty, as
thofe on which I made experiments were feeble and fickly.
Common wood-lice on the other hand, after being killed in
fpirit of wine, I could not bring to life by the fame means.
Further experiments on this fubject I fhall leave to natural-
ifts and phyficians, who, perhaps, may infer from the aboye
obfervations, that warm wood-afhes might be employed, not

deiva wine which had been bottled in Virginia. In fome of the bottles he
found a few dead flies, which he expofed to the warm fun, it being then
the month of July, and in lefs than three hours thefe apparently dead ani-
mals recovered life which had been fo long fufpended. At firft they ap-
peared as if convulfed ; they then raifed themfelves on their legs, wathed
their eyes with their fore feet, dreffed their wings with thofe behind, and
began in a little time to fly abour. Ep:r,

without

On rendering Writing indeftruétible by Fire. 174
without advantage, by way of fomentation, to gouty and pa-
talytic limbs, and for thofe afflicted with rheumatic com~
plaints.

XII. Chemical Experiments refpecting different Methods of
rendering Paper and the Writing on it indefirudtible by
Fire. By Mr. L. BRUGNATELLI. From Crell’s Che-
mical Annals for 1797.

Various Methods of rendering Writing indeftruGible.

{ Concluded from Page gz, ]

W uen I had difcovered the means by liquor of flint
to render paper fo much lefs combuftible, and alfo in parti~
cular to prevent its being converted into afhes, I refolved to
examine how common ink would ftand on paper prepared
in that manner. I imagined that ink, on account of the
oxydated metal contained in its mixture, would not be fo
eafily deftroyed by the fire; for, though it is not naturally
black when freed from the acid of galls, it muft however be
fomewhat vifible as foon as the fubftance on which it is
put is rendered indeftructible. And this I actually found
_ ‘to be the cafe, after writing a few lines with good common
ink upon a leaf of paper which had been carefully prepared
with liquor of flint, and putting it mto the fire till it was
burnt toacoal. I examined the writing with attention, and
found that feveral words which I had written upon it could
be read, though the paper was reduced to a coal. All the:
words could not indeed be diftinguifhed with the fame clear-
nefs, and therefore they could not be all properly read,
‘Some of them had a red'ochrey colour, and thefe were the
eleareft ; others were blackifh, and fome were of fo dark’a.
tint that they were almoft entirely blended with the colour
‘ofthe charred paper: the laft were totally illegible. Thefe
phenomena are perfectly agreeable to the nature of oxydated

%, iON,

74 On rendering Writing indeflrudtible by Fire.

iton, which, ds is well known, affumes the above-mentioned
tints, according as it contains more or lefs oxygene or carbori.

On account of the oxydated iron, as I could not émploy
common ink for my propofed object, I fought among the
oxydated metals for one that was capable of ftriking the eye
ona black ground, and which at the fame time would com-
bine with common ink *.

To comimon ink I added a portion of oxydated bifmuth,
which, according to its own nature, is exceedingly white,
and which on a black ground would produce vifible charac-
ters that muft then be legible. I prepared thé mixture, and
obtained a fomewhat thick ink, which did not flow readily,
and with which I could write a few lines, but not without
difficulty. Paper written ‘upon with this ink | burnt in a
wood fire, and examined it as foon as it was reduced to’
eoal. I however found that the words were not more legible
than thofe written with common ink; for the oxydated bif-
muth communicated Its oxygene to the inflammable parts of
the mixture, and the whole was revived into @ metallic
regulus : feyeral {mall grains of regulus of bifmuth could
therefore be diftinguifhed in it with the naked eye. I mixed
common ink with feveral other oxydated metals, and with
feveral kinds of earths; but the ink by thefe was fo much
changed im its colour and confiftence, that I thought it un-
neceffary to pay any farther attention to it: I had recourfe;
therefore, to diffolved metals, becaufe ink by thefe is not
changed in its confiftence, as by oxydated metals, and parti-
cularly earthy bodies.

But before I made any mixture with common ink, I withed
to try what colour characters made with diffolved metals
only would affume, on paper prepared as before; when re-
duced to coal.

_ I wrote, therefore, on different leaves of paper, which had
been foaked in liquor of flint, with a common folution of

* For common ink any other black dye may be fubftituted.

gold Fa

On rendering Writing indefirudtible by Fire. 175
fold; nitrite of filver, copper, tin, Iead, bifmmuth, cobalt;
antimony, and manganefe. None of the characters writtei
with the above folutions could be read by the naked eye,
except that written with nitrite of copper, which appeared
of a beautiful green colour. I burnt all thefe leaves in 2
flame, and the refults were as follows :

The charatters-made with folutions ef gold. and filver
were not vifible on the charred paper, on account of the
dark tint which they affumed in the fire. The cafe was the
fame with thofe charaéters made by folutions of cobalt, an-
timony, and lead.

I have found that diffolved nitrite of cobalt may be em-
ployed with great advantage for making fympathetic ink, not
inferior to the celebrated ink prepared from the fame metal
diffolved in the nitro-muriatic acid, or aqua-regia; which,
as is well known, becomes vifible of a beautiful green colour’
by heat, and difappears in the cold. Characters written with:
diffolved nitrite of cobalt became vifible, of a beautiful violet
colour, on paper prepared as above. I held the leaf of paper,
on which I had written with the before-mentioned. folution,
a few feconds over the fire; and when I took back the leaf I
could read the characters, before invifible, as they now ap-
peared of a violet colour; but the colour gradually difaye
peared, and the writing again became itvifible. When I
held the paper fo near the fire that it was a-little finged, the’
eharacters appeared white, and difappeared. again in the cold.

Charaéters made with nitrite of antimony were not vifible,
becaufe they were as black as the charred paper. But when’
the paper was held to the light they could be read a little,
beeaufe the oxydated metal made the characters exceedingly
opaque, and therefore eafily to be diftinguifhed from the ref
of the paper, which was more or Jefs tran{parent.

Charaéters' made with diffolved nitrite of tia gave the
fame refult as the’ preceding. Thofe alfo made with a fo»
Jution of bifmuth were fcarcely vifible after being in the fire;
and when the fire was brifk it deftroyed the charred paper,

while

t46 On rendering Writing indeftru€tible by Fire.

while the oxydated bifmuth was converted into metal #,
The invifible letters made with a folution of this metal can
be read alfo, if the paper be dipped into pure water. By
this fimple procefs the charaéters appear of a white colour;
as the paper becomes fomewhat darker. The writing, how-
ever, may be read better if the paper be then held to the
light, becaufe the paper, which becomes fomewhat tranf-
parent, fuffers the charaéters, which are altogether dark, to be
feen.

I thought it iuineceffary to make airy experiments with dif-
folved arfenic and quickfilver, becaufe their oxydes eafily
fuffer the oxygene to efcape; fublime in the fire, and then
entirely fly off from the burning body.

Of all the metallic falts, I found only nitrite of copper and
zinc fit for my propofed object; for the calces of thefe metals
eontinue fixed in the fire, and fhew themfelves afterwar.’s in
durable and bright colours.

The characters which I wrote with diffolved nitrite of
copper were exceedingly vifible, of a copper colour on the
charred paper, and this colour can be well diftinguifhed on a
dark ground. When I wrote with diffolved ammoniacal
copper, inftead of nitrite of copper, the characters affumed
in the fire a dark red colour, which approached that of cin-
nabar. Diffolved nitrite of zinc, however, is the beft of all
the fubftances with which I made experiments, becaufe
characters written with it on paper prepared by liquor of
flint were legible; and it is therefore preferable to folutions
of copper, or of any other fubftance.

When I wrote with diffolved nitrite of zinc, the characters
were not vifible; but when the paper was burnt they were

* To obferve this phenomenon better, it will be fufficient to write on 4
leaf of paper which has been impregnated with fal-ammoniac, and then
to burn it over the flame of a candle. The charred paper remains fmooth;
but at the places where the charaéters were written a beautiful fmall
border of regulus of bifmuth is feen, fo that when the paper is held to the

light many of the words written upon it may be read.
fo

On rendering Writing indeftruftible by Fire. 477
fo vifible, in a clear white colour on a datk ground, that they
eould be read with as much éafe as characters written with
the beft ink on white paper.

* T fhall now examine whether diffolved nitrite of zinc;
- which produces fo beautiful a fympathetic ink, can be com-
bined with common ink, without the latter being fo changed
in its colour as to be rendered unfit for ufe as before. I
made this mixture, and found that the ink became fome-
what pale by the nitrite of zinc, on account perhaps of the
nitrous acid, which probably leffened the combination of the
acid of galls with the iron: but I could write with it very
well on paper prepared by my liquor of flint; for the colour
of common ink mixed with nitrite of zinc, which appeared.
on common paper to be fomewhat weakened, became fo
dark on prepared paper, that words written with it appeared
more confpicuous ‘than thofe written with common ink.
The white colour of which the characters appeared, on the
charred paper, was not changed by the mixture of ink, as I
was fully convinced by repeated experiments.

One part ‘of my curiofity was ftill not gratified, as I withed
to know of what colour the diffolved metals would appear
on paper impregnated with different falts. For has pape
I made the following experiments :

I wrote on paper, which had been impregnated with acetite
of barytes, with a folution of gold, nitrite of filver, coppers
bifmuth, tin, lead, antimony and zinc. The charaéers
written with a folution of gold appeared on the charred
paper of a beautiful poppy red, and thofe with a folution of
copper of a dark yellow. Thofe written with a folution of
antimony, zinc, bifmuth, tin and lead, could not be feen.

' I wfote alfo with folutions of the above metals on paper
which had been foaked in muriate of lime. The charaéters
‘written with folutions of gold and filver appeared on the
paper like thofe written on paper foaked in acetite of batytes.
Thofe written with folutions of lead and bifmuth appeared
_ white; and thofe written with a folution of copper appeared
Vou. I. N red,

178 On rendering Writing indeflruélible by. Fires
red. Thofe written. with folutions of tin, antimony and ~
zine, were not legible. Paper impregnated with fulphite of
potafh was totally deftroyed in the flame, as above remarked.
I thought it neceflary therefore to make. experiments with
other fulphites; becaufe I had before obferved that fuch falts, -
by means of inflammable bodies, are converted into fulphu-—
reous bodies.

I wrote alfo with the common diffolved metals, on paper
which had been impregnated with muriate of foda. The
characters written with a folution of gold could. fearcely be
diftinguifhed of a dark red colour; but thofe written with
all the other diffolved metals were not legible.

I wrote with the fame folutions on paper which had been
foaked in a folution of muriate of ammoniac, but, none of
the characters were vifible on the paper when reduced to coal.

I wrote, in the laft place, with the fame fubftances on
paper which had been foaked in a folution of nitrite of lime,
and, when reduced to coal, I could read: the charaéters writ-
ten with a folution of gold of a beautiful rofe red; and
thofe written with a folution of filver of a yellow colour;
but the charred paper was white. The other characters
were not legible, except thofe written with nitrite of bif-
muth, which had affumed a blackith colour.

The other pieces of paper foaked in folutions of different
falts gave no refult worthy of notice.

The above obferved effeéts and before-mentioned chemi-
cal preparations were the means of leading me to feveral
pleafant experiments. I wifhed, for example, to bring it
about that the burnt paper fhould be converted into.a white
indeftrudtible coal, on which the characters might be legible
of different colours, and aecomplifhed my objeé in the fol-
lowing manner :—I rubbed fome gum arabic mixed with pure:
magnefia by means of a hair brufh, over the paper foaked in
liquor of flint. When the paper was dry, I wrote on it fe~
veral lines, fome with a folution of gold, and others with a
folution of antimony in aqua-regia. The charaéters made

with

On rendering Writing indeftrudlible by Fire. 179

with both thefe folutions were totally illegible. 1 then
threw the prepared paper thus written upon into the fire ;
and when it was wholly reduced to a coal, all the lines could
be read of a black colour on a white ground, fo that the cha-
raters were almof like thofe written with common ink on
white paper. If it be required to make the folutions of
gold and antimony black, that the words written with them
may be more diftinguifhable before the paper is burnt, it s
will only be neceffary to add a little common ink to them,
but fuch as contains as fmall a quantity as poffible of the
fulphite of iron*.

I dipped paper which had been prepared with liquor of
Aint in a faturated folution of nitrite of zinc, and fuffered
it to become exceedingly dry in the fun. I then wrote on
feveral bits of this paper with the folutions of different me-
tals, and a few hours after reduced them all to coal, by
holding them one after the other in the fire. Characters
written with diffolved nitrite of copper appeared of the co-
Jour of metallifed copper; thofe written with diffolved ‘ni-

: trite of iron, or bifmuth, of a yellow colour; thofe with

* In the fame manner as charred paper is made to affume a white co-
Jour when it has been before wafhed over with a mixture of gum arabic
and magnefia, it may be made to affume any other colour if the paper be
dipped fometimes in one and fometimes in another of the above-mentioned
folutions, as the charaéters on the charred paper will then affume fome-
times one colour and fometimes another. If paper, for example, which
has been foaked in liquor of Aint, be held alittle in a {olution of fulphite
of copper, and then dried, the paper will afume a beautiful green colour.
If the paper be burnt, it affumes a copper colour. If you write on papery
already tinged green, with any metallic folutions of metals which are not fo
eafily decompofed by the aétion of the fire, fingular phenomena will be
obferved. If you write on it with fulphite of iron, the charaéters will be
read of a yellowifh colour. When the paper is reduced to coal, the cha-
rafters are ftill feen yellow. If you write with diffolved nitrite of anti-
mony, the charaéters appear whitifh. If the charaéters are written on
{uch paper with nitrite of zinc, they are invifible; but when the paper is
reduced to coal, they appear of a filver colour, &ce

N 2 diffolved

180 ~ | On Tefls for deleetinig. ‘ y

diffolved nitrite of antimony, black; and thofe with a. folia

tion of gold, of a gold colour. Thofe made with the laft

folution appeared feveral times of the colour of black vel-

vet. When you write on the above-mentioned paper with

iron diffolved in diluted nitrous acid, the characters will

appear of an orange yellow colour, if the paper be often
_ heated without reducing it to coal.

P.S. Tani now employed in endeavouring to difeover a
method of rendering paper prepared with liquor of flint
fironger, fo that when burnt it may not be fo friable, in
order that when feveral fheets of paper are, burnt upon each
other they may be eafily feparated, and the whole writing on

. them be read. As foon as I have derived any refults from
my experiments, I fhall not fail to communicate them.

XTIL. On Toft Liquors for dete@ing Acids and Alkalis in Che-
mical Mixtures. Extraéted from Mr. Warr’s Paper on that
Subjeé in the Philofophical Tranfaétions for 1798, Part f.

Mr. WATT of Birmingham, to whom the philofophical
world is fo much indebted for various difcoveries and im- -
* provements, has turned his attention to this fubject, and has
favoured the world with the refult of his inveftigation. He
obferves, thatthe great degree of fenfibility of an infufion of
litmus (fyrup of violets having been for fome time out of
ufe as a teft, as it has been found not to be fufficiently nee
curate), the blue colour of which is changed into red by the
prefence of a very minute quantity of any acid, would leave
very little neceflity to fearch for any other, were there reafon
to believe that it is always a teft of the exact point of fatu-
yation of acids and alkalis, which the following fa& feems
to call in quettion :

** A mixture of phlogifticated ni-
trous acid with an alkali will appear to be acid by the teft
of htmus, when other telts, fuch as the infufion of the pe-
tals of the feurlet rofe, of the blue iris, of violets, and o¢

mate ; other

Acids and Alkalis, _ 181

other flowers, brah fhew the fame liquor to be alkaline by
turning green.’

Paper ftained with infufions, or with the juices of the pe-
tals of fuch flowers as have been juft mentioned, though an

excellent teft for alkalis, is not fo eafily affected by acids as

litmus, and, by keeping, lofes in a {hort time much of its
fenfibility.
To obtain frefh made tefts from vegetables, few of which

_ave to be met with in winter, was a matter of confiderable

moment. Mr. Watt found the red cabbage (braflica rubra)
to furnifh the beft. In its frefh {tate it is more fenfible both
to acids and alkalis than even litmus, and more decifive from

‘its being naturally blue; turning green with alkalis, and red

with acids.

Mr. Watt extracts the colouring matter from the thin
parts of the leaves only. He minces them fmall, and digefts
them in water about the heat of 120° for a few hours. If
not to be immediately ufed, as it is apt to fpoil, Mr. Watt
recommends to {pread the minced leaves on paper, to dry
them in a gentle heat, and then to put them in botiles well
corked. To prepare the teft, infufe or digeft thefe dried
Jeaves in water acidulated with fulphuric acid till they give
out their colour; then ftrain the liquor through a cloth, and
add to it whiting or chalk, ftirring it frequently, until it be-
comes a true blue, neither inclining to green nor to purple,

When this point is gained, filter it immediately; other-

wife it will become greenith a ftanding on the chalk, It
will “depofit fome gypfum, and, by adding a little fpirit of
wine, will keep good for fome days. Too much fpirit de-
flroys the colour. wanted to be kept longer, neutralife
it by means of a fixed alkali inftead of chalk, But as none
of thefe means will preferve the liquor long without” requir-
ing to be neutralifed afrefh juft before it is ufed; and as the
fermentation which it undergoes, and perhaps the alkalis or
{pirit of wine mixed with it, feem to leffen its fenfibility ; in

order to preferve its virtues, while it is kept in a liquid ftate, .

N3 fome

e

182 Account of the American Sugar Maple.

fome frefh leaves, minced as has been dire&ted, may be in-
fufed in a mixture of vitriolic acid and water, of about the
degree of acidity of vinegar; and it may be neutralifed as it
is wanted, by chalk, or fixed or volatile alkali. Avoid an
excefs of alkali, as it will turn the colour yellow.

_ By the fame procefs Mr. Watt made a red infufion of vio-
lets, which on being neutralifed formed a very fenfible teft;
but how long it might be preferved, he had not determined.

Mr. Watt recommends to ufe the tefts in a liquid ftate; as
he obferves, and with juftice, that the fize and alum in writ-
ing-paper in fome degree fix the colour, while paper not
fized becomes too tranfparent, when wetted, to render
fma!l changes of colour perceptible.

To the above ufeful hints of’ Mr. Watt we fhall add ano-
ther.—The {kins of red radifhes yield by being bruifed a very
fenfible teft, and, no doubt, might be preferved by the means
he has pointed out.

XIV. An Account of the Sugar Maple of the United States,
by Bensamin Rusn, M.D. Profeffor of the Infittutes of
Medicine in the Univerfity of Pennfylvania, communicated
by Rogert Joun THornton, M. D. Leéturer on Me-
dical Botany at Guy’s Ho/pital. .

r

T HE acer faccharinum of Linnzus, or fugar maple tree,
is found in great abundance in the weftern counties of all the
middle ftates of the American Union. Thofe which grow
in New York and Pennfylvamia yield the fugar in a greater
quantity than thofe which grow on the water of the Ohio,
They are’ when at maturity, that is, when about twenty years
old, as tall as an oak, and from two to three feet in dia-
meter. They put forth a beautiful white bloffom in the
fpring before they fhew a fingle leaf. The colour of the
bloffom diftinguifhes the fugar maple from the acer riv«
brum, or common maple, which has a red flower. Its fmall

branches

Account of the American Sugar Maple. 183
branches were cut by the firft fettlers for the fuppott of
cattle during the winter; who throve greatly upon them.
The wood is extremely inflammable, and. therefore makes
fine fire-wood, Its afhes afford a great quantity of pot-afh,
exceeded by few, or perhaps by none, of the trees that grow
in the woods of the United States.

The acer faccharinum is not injuted by tapping; on the
contrary, the oftener it is tapped, the more fyrup is obtained
from it. The effeéts of a yearly difcharge of fap from the .
tree in improving and increafing the fap, is demonftrated
from the fuperior excellence of thofe trees which have been
perforated in an hundred places by a {mall wood-pecker
which feeds upon the fap. The fap of fuch trees is much
fweeter to the tafte than that obtained from trees which
have not been. previoufly. wounded, and more fugar is
afterwards procured. In this laft particular it follows a law
of the animal ceconomy. It is well known, that when a
_ perfon has been once tapped, the procefs requires afterwards
to be more frequently repeated. A fingle tree has not only
furvived, but flourifhed after forty-two tappings in the fame
number of years.

A tree of an ordinary fize yields, in a good feafon, from
twenty to thirty gallons of fap, from which are made from
five to fix pounds of fugar. To this there are fometimes
rematkable exceptions. Samuel Low, Efq. a juftice of peace
in Méntgomery county, in the State of New York, informed
Arthur’ Noble, Efg. that he had made twenty pounds and
one ounce of fugar from the 14th to the 23d of April, in the
year 1789, from a fingle tree that had been tapped for feveral
fuccéflive years before. The quantity obtained per diem
varies from five gallons to’a pint, according to the variations
of the weather. “The influence which fis. has in increafing
or ‘leffening the difcharge of the fap is very remarkable. I
have feen a journal of the effects of heat, cold, moifture,
drought, ce thunder, upon the difcharges from the fugar
tree; which ‘difpofes me to believe there is fome foundation
ro N 4 - in

184 Account of the American Sugar Maple.
in Dr. Tongue’s opinion, who fuppofes that changes in the
weather of every kind might be as readily afcertained by
difcharges of fap from trees, as by the barometer. (Vide
Philofophical TranfaGtions, N° 68.) Warm days fucceeding
frofty nights are moft favourable to a plentiful difcharge of
fap. If frofty nights fucceed a warm day, there is always a
total fufpenfion of the difcharge*.

The

* Dr. Hale, in his Vegetable Statics, relates that he cut down a vine, and
cemented to its mutilated {ump glafs tubes, each 7 feet long, and one
fourth of an inch diameter, with brafs caps, by which they were {crewed
on one above another, till they rofe to the height of 36 feet.

By thefe gages it appeared,

rft. That the fap began to rife March 10, when the thermometer by
day ftood only at 3 degrees above the freezing point.

2dly. That, April 18, it was at its height and vigour. °

3dly. That from that time to May 5, the force gradually decreafed.

4thly. That it conftantly rofe fafteft from fun-rife to about 9 or 10 in
the morning, and'then gradually fubfided till about 5 or 6 o'clock in the
afternoon.

sthly. That it rofe fooner in the morning after cool weather, than after
hot days, and in proportion to the coldnefs of the night and fubfequent
heat.

éthiv. That after feveral fucceffive cold days and nights, the fap would
rife during the whole day, if it chanced to be fine, although floweft at noon.

zthly. That if warm weather had made the fap flow vigoroufly, that
vigour would be abated immediately by a cold eafterly wind amd a cloudy
fun, when the fap would fink at the rate of an inch per minute ; but when
the fun fhone out, and the wind fhifted, it rofe again as ufual. ;

8thly. The oldeft vines were fooneft affefted by a change of tempera-
ture, and in them the fap firft began to fink. F ;

othly. And, on the contrary, when the tube was fixed toa very fhort
ftump of a young vine, and at only 7 inches from the ground, the fap
flowed inceffantly, and fafteft of all, in the greateft heat of the day, finking

‘only after fun-fet.

He then makes this general conclufion, that the rapidity. with which the
fap circulates in the vine during the fpring, is five times greater than the
rapidity with which the blood flows in the arteries of a horfe; that it is
eonfiderably flower in the fummer than in {pring, very mow in autumn,

and geafes altogether in the winter. ;
The

a i MIT sim

Account of the American Sugar Maple. 185

The fap ufually flows for fix weeks, varying according to
the temperature of the weather. The feafon for tapping is
in February, March, and April. During the remaining part.
of the {pring months, as alfo in the furamer, and in the be-
ginning of autumn, the maple tree yields a thin fap, but not
fit for the manufactory of fugar.
| Baron La Hontan gives the following account of the fap
of the fugar maple tree, when ufed as drink, and the manner
of obtaining it. The tree, fays he, yields a fap which has a
much pleafanter tafte than the beft lemonade or cherry
water, and is the wholefomeft drink in the world. This
liquor is drawn by cutting the tree two inches deep in the
wood, the cut being made floping to the length of ten or
twelve inches ;.at the lower end of this gafh, a knife is
thruft into the tree flopingly, fo that the water runs along
the cut or gafh, as through a gutter, pervades the knife, and
falls upon fome veffels placed underneath to ‘receive it.
The gath does no harm to the tree. Some trees will yield
five or fix bottles of this water in a day, and many inhabitants
of Canada might draw twenty hogfheads of,it in one day, if
they had a mind to notch all*the maple trees upon their
plantations ; but common things are flighted, and f{earce any
but children think of extracting this liquor from the trees.

The mode of tapping is different, and is performed
with an axe or an auger. The latter is preferred, from ex-
perience of its advantage. It is introduced about three
quarters of an inch, and is afterwards deepened gradually to
the extent of two inches. A {pout is introduced about half

The above experiments clearly demonftrate, that it is not from heat
and light alone that the fap rifes in the vine, or any other tree; for, if that
were the cafe, it would increafe as the heat increafed; it would be greateft
in the noon-dayy and in the height of fummer, and lefs in {pring than in
autumn, whereas the reverfe is here fhewn to be the cafe. It muft there-
fore depend on the irritability of the fibres compofing the veffels, which
gets exhaufted by the ftimulus of heat and light, and is accumulated by its
abfence. T. -

an

186 Account of the American Sugar Maple.

an inch into the hole, and it projects from three to twélve
inches, The operation of tapping is firft done on the fouth
fide; and when the difcharge of fap leffens, an opening is
made with the auger on the north fide, when an abundant
flow takes place.

Wooden troughs large enough to contain three or four
gallons are placed under the fpout to receive the fap, which
is carried every day to a large receiver made of wood. From
this receiver it is conveyed, after being ftrained, to the boiler.
The following facts have been. afcertained by experiment:
The fooner the fap is boiled, after it is colle&ted from the
tree, the better. The larger the veffel the more fugar is ob-
tained. The fugar is, alfo improved by ftraining the fap
through blankets, or cloth, either before or after it is half
boiled. Some fatty fubftance is added to the fap in the
kettle, to prevent its boilingover. Lime, eggs, or new milk,
is mixed, with it in order to clarify it. I have feen clear
fugar made without the addition of either of them. A
fpoonful of flack lime, the white of one egg, and a pint of
new milk, are the ufual proportions of thefe articles, which
are mixed with fifteen gallons of fap. The maple fugar
clarified with milk alone had the evident fuperiority of all
others. After being fufficiently boiled, it is grained, and
clayed, and afterwards refined, or converted into loaf fugar.
The method of conduéting each of thefe procefles is fo
nearly the fame with: thofe which are ufed in the manufac-
tory of Weft India fugar, and are fo generally known, that
I need fpend no time in deferibing them.

There are two other methods of reducing the fap to fugar.
The firft is by freezing. This method was tried by Mr. Scott,
a farmer in this ftate, with great fuccefs. He fays, that one
half of a given quantity of fap reduced in this way, is better
than one third of the fame quantity reduced by boiling. If
the froft fhould not be, intenfe enough to reduce the fap to

the graining point, it may afterwards be. expofed ss — ‘>

attion of fire for that purpofe.
sce

Account of the American Sugar Maple. 187

Secondly, by /pontancous evaporation. The hollow ftump of
a maple fugar tree, which had been cut down in the fpring,
and which was found fome time after filled with fugar, firft
fuggefted to our farmers this method of obtaining fugar. So
many circumftances of cold and dry weather, large and flat
veflels, and above all fo much time is neceffary to obtain
fugar by either of the above methods, that the moft general
method among our farmers is to obtain it by boiling.

The kettles and other utenfils of a farmer’s kitchen will
ferve moft of the purpoies of making fugar, and the time re-
quired for the labour (if it deferves that name) is at a feafon
when it is impoffible for the farmer to employ himfelf in
any fpecies of agriculture. His wife, and all his children
above ten years of age, may affift him. The following re- -
ceipt was publifhed in the Albany Gazette: “ Received of
William Cooper, Efg. fixteen pounds for 640 pounds of fu-
gar, made with my own hands, without any affiftance, in
lefs than four weeks, befides atteading to all the other bu-
finefs of the farm. John Nicholls.’’ A fingle family con-
fifting of a man and his two fons, on the Maple Sugar
Lands between the Delaware and Sufquehannah, made 1800
pounds of maple fugar in one feafon. Not more knowledge
is neceflary for making this fugar, than is required to make
cyder, beer, &c, and yet one or all of them are made in
moft of the farm-houfes in the United States,

Let us now take a comparative view of this fugar with
that obtained from the cane, with refpe& to its quality,
price, and the guantity that. might probably be made in the
United States, each of which I fhall confider in order:

1. The quality of this fugar is neceflarily better than that
which is made in the Weft Indies. It is prepared in a fea-
fon when not a fingle infeé&t exifts to feed upon it, or to
mix its excretions with it. The fame obfervation cannot be
applied to the Weft India fugar. The infects and worms

‘ which prey upon it, and of courfe mix with it, compofe a
page in a nomenclature of natural hiftory, I fhall fay no-
thing

188 Account of the American Sugar Mapl..
thing of the hands which are employed in making fugar in

the Weft Indies; for flaves have not that obligation to clean- _

limefs which thofe have who work for their own benefit, and

have received a proper education. It has been conceived -

that the maple fugar is inferior to the Weft India fugar in
ftrength. The experiments which led to this opinion I fuf-
_ peét have been inaccurate, or have been made with maple
fugar prepared ina flovenly way. I have examined equal
quantities by weight of both the grained and the loaf fugar,
in hyfon tea, and in coffee, made in every refpect equal by
the minute(ft circumftances that could affect the quality or
tafte of each of them, and could perceive no inferiority in the
ftrength of the maple fugar.. The liquors which were to de-
vide this queftion were examined at the fame time by Alex-
ander Hamilton, Efq. fecretary of the treafury of the United
States, Mr. Henry Drinhur, and feveral ladies, who all con-
curred in the above opinion.
3. Price. Whoever confiders that the gift of the fugar
‘maple tree is from a benevolent Providence; that we have
many millions of acres in our country covered with them ;
that the tree is improved by repeated tappings ; and that the
fugar is obtained by the frugal Jabour.of a farmer’s family
and at the fame time confiders the labour of cultivating the
lugar cane, the capitals funk in fugar works, the firft coft of
flaves and cattle, and the expences of provifions for both,
&c. will not befitate in believing that the maple fugar may be
manufactured much cheaper, and fold at a confiderably e/s
eee than that which is made in the Weft Indies.

. The refources for making a fufficient guantity of. this
facays not only for the confumption of the United States, but
for exportation, will appear from the followi ing facts :—There
are in the ftates of New York and Pennfylvania alone, at
leaft ten millions of acres of land which produce the fugar
maple tree in. the proportion of thirty trees to one acre,
Now, fuppofing all the perfons capable of labour in a family,
zo confift of three, and each perfon to attend 150 trees, and

each

ie ee

Account of the American Sugar Maple. 18g

each tree to yield 5 pounds of fugar, the product of labour of
' 60,000 families would be 135,000,000 pounds of fugar, and,
allowing the inhabitants of the United States to compofe
600,000 families, each of which confumed 200 pounds of
fugar a year, the whole confumption would be 120,000,000)
‘pounds a year, which would leaye a balance of 15,000,000
pounds for exportation, Valuing the fugar at 6—go of a
dollar per pound, the fum faved would be 8,000,000 dollars
of home confumption, and the fum gained by exportation
would be 1,000,000 dollars.
» The maple fugar alfo affords excellent vinegar; its molaffes
is capable of affording a very pleafant fummer beer. The
fap is alfo capable of producing fpirit; but we hope this -
‘wholefome juice will never be proftituted to fuch a purpefe.
A diet confifting of a plentiful admixture of fugar has many
advantages.

Sugar affords the greateft quantity of nourifhment in a
given quantity of matter of any fubftance in nature. Hence
the Indians ufe it in their excurfions. ‘They mix a certain
quantity of maple fugar with an equal quantity of Indian
corn, dried and powdered. This mixture is packed up in-
little bafkets. A few fpoonfuls of it mixed with half a pint
of fpring water, afford them a pleafing and ftrenzthening
meal. From the great degree of ftrength and nourifhment
which are conyeyed into animal bodies by a {mall bulk of
fugar, it may be given to horfes with great advantage. A
pound of fugar with grafs or hay, I have been told, has fup-
ported the ftrength and fpirits of a horfe during a whole ~
day’s labour in one of the Weft India iflands. A larger _
quantity given alone has fattened horfes and cattle during the
war before laft in Hifpaniola, for a period of feveral months,
in which the*exportation of fugar and the importation of

in were prevented by the want of {hips.

- 3. A plentiful ufe of fugar is the beft preventative of
worms. The author of nature feems to have implanted a
love for fweets in all children for their growth, and to ward
off the difeafe of worms. “
home Aco

99 Account of the American Sugar Maple.

4. I think it probable, that. the frequency of malignant
fevers of all kinds has been leffened by this diet, and that its
more general ufe would defend that clafs of people who are
moft fubje&t to malignant fevers from being fo often affected

by them.
5. It has been faid, that fugar injures the teeth ; -but this
opinion now has fo few advocates, that it does not merit a
ferious refutation. :

It has been a fubject of enquiry, whether the maple fugar
might not be improved in its quality, and increafed in its
quantity, by culture. From the influence which culture has
upon foreft and other trees, it has been fuppofed, that by
tranfplanting the maple fugar tree into a garden,: or by de-
ftroying fuch other trees as fhelter it from the rays of the
fun, much advantage might accrue. I know but of one fact.
A farmer in Northampton county, in the ftate of Pennfyl-
vania, planted a number of thefe trees above twenty years
ago in his meadow, and he declares that the quality is fo

improved, that from three gallons of the fap he obtains every -

year a pound of fugar; and it is a known circumftance
that, to produce the fame quantity of fugar from the trees
which grow wild in the wood, it requires five or fix gallons
of fap. To tranfmit to future generations all the advantages
which have been here enumerated, it is neceffary that this
tree fhould be cultivated in the old and improved parts of.

the United States, and a bounty given upon the maple fu- ©

gar by Government. Afterwards men would find out their
own advantage in rearing them. An orchard confifting
of 200 trees, planted upon a-common form, would yield more
profit than the fame number of apple or any other trees.
If a greater expofure of a tree to the aGtion of the fun has
the fame effe&t upon the maple that it has upon other trees,

a larger quantity of fugar might reafonably be expeéted —
~ from each tree*planted in an orchard. Allowing it to be —
only feyen pounds, then 200 trees will yield 1400 pounds |
of fugar; and deduéting 200 from the quantity for the con= —

fumption: of the family, there will remain for fale 1200 —

} pounds BI

:

Mr. Park’s Journey into Africai 19%
pounds, which at 6—go of a dollar per pound will yield an
annual profit to the farmer of 80 dollars. Should this mode
of tranfplanting for the purpofe of obtaining fugar be fuc-
eefsful, it will not be anew one. The fugar cane of the
Weft Indies was brought originally from the woods of the
Eaft Indies by the Portuguefe, and cultivated at Madeira,
from whence it was tranfplanted direCtly or indire&ly to all
the fugar iflands of the Welt Indies.

In contemplating the prefent opening profpe&ts in human
affairs, I am led to expeét that a material fhare of the hap-
pinefs which Heaven feems to have prepared for all man-
_ kind, will be derived chiefly from the manufactory and
general ufe of the maple fugar, which I flatter myfelf will
not be confined to us, but will extend itfelf to other na-
tions. With this view of the fubjeét, I cannot help contem-
plating a fugar American maple tree with a fpecies of affec-
tion and even veneration; for I have perfuaded myfelf to
behold in it the happy means of rendering the commerce
and flavery of our African brethren in the Weft India iflands
as unneceflary as it has always been inhuman and unjuft *,

XV. An Account of Mr. Parx’s Journey into the Interior
Parts of Africa. From the Proceedings of the African
Affociation, 1798.

Te account of the proceedings of the African Affo-
ciation, from which the following extra& is taken, though it
abounds with many curious particulars which we have been
obliged to omit, contains but a fmall part of the information
obtained by Mr. Park during the courfe of his peregrina-
tions in the wild regions of Africa. A detailed relation of

* The friends to the abolition of the Slave Trade fhould not allow the
_ information contained in this article to efcape their notice. It would-re-
quire very little expence or induftry to introduce the fugar maple into
England, where it would probably thrive as well as in America. T.

xy | this

.

392 Mr. Park’s Tourney into Africa.

this enterprifing traveller’s journey, and of the difcoveries he’
made, is releiesd fora large volume, to be publithed by fub-
feription, which we are happy to find announced, and we
have no doubt that the author will meet with that reward
from the public to which he is fo juftly entitled by his forti-
tude and perfeverance. We cannot help obferving alfo, that
great thanks are due to the African Affociation, for their
exertions to procure information refpecting the continent of
Africa, and thus to pave the way for the civilifation 6f its
inhabitants. The Report printed fo for the ufe of the mem-
bers does great credit to the literary talents of Bryan Edw ards,
Efq. by whom it was drawn up.

On the 22d of December 1795, Mr. Park took fe de-
parture from the houfe of his friend Dr. Laidley, at Pifania, °
on the banks of the river Gambia, and direéted his courfe
eafterly for the kingdom of Woolli. He was accompanied
by two negro fervants, natives of the country, one of,
whom {poke Englifh tolerably well, and ferved him as inter-
preter; the other was a boy prefented to him by Dr,-Laid-
ley. He had alfo a horfe for himfelf, and two affes-for his
fervants. His bageage confifted chiefly of provifions for two
days, a fmall affortment of beads, amber and tobacco, for the
purchafe of a frefh fupply as hé proceeded: a few changes”
gf linen and other neceffary apparel, an umbrella, a pocket
fextant, a compafs, and a thermometer, together with two
fowling-pieces, two pair of piftols, and fome other fmall
articles. ‘

Mr. Park reached Medina, the capital of Woolli, on the
third day, and was received by the fovereign or chief, named ”
Jatta, with much kindnefs. This prince wifhed to per-

fuade Mr. Park not to profecute his journey any farther,

by pointing out the dangers and difficulties he would have
to encounter ; “but finding his remonftrances had no effect,
he furnifhed him with a guide to Bondon,, and fuffered him

to depart. i
Leaying Medina, Mr. Park proceeded onwards, and on
9 the :

ee

in

Mr. Park’s Journéy into Africa. 193
the 21ft of December reached Fatteconda, the capital of
the kingdom of Bondou. The king of this country was a.
Pagan, like that of Woolli: but he had adopted the Moor-
ith name of Almami, and feems alfo to have imbibed fome-
What of the Moorifh difpofition ; for though Mr. Park
prefented to him his umbrella and fome other articles, he
compelled him to ftrip in his prefence and furrender his
voat, which he faid he fhould referve for his own wearing
on great and public feftivals. In return, however, he gave
our traveller five drachms (minkalliés) of gold duft, and
loaded him with provifions.

Departing from Fatteconda on the 23d of December, Mr.
Park proceeded the two following days to a place called
Joag in the kingdom of Kajaaga, a country bounded on the
north by the Senegal river. The natives are called Sera-
Woollies, and feem to be pure negroes. The appearance of
a white man among them excited great curiofity. The king
commanded that he fhould be brought before him ; and it
was with fome difficulty that Mr. Park, who had been cau-
tioned to avoid him, declined the interview, arid got out of
his dominions with the lofs of about one half of his goods
and apparel.

The name of this rapacious chief was Backeri.. He had
recently fallen out with a neighbouring prince, the foyereign
of Kaffon, a country to the north-eaft; and it happened: that
the king of Kaffon’s nephew was in Bacheri’s capital, en-
deavouring, but in vain, to effet a reconciliation at the
time of Mr. Park’s arrival atJoae. This young man, finding
that our traveller propofed proceeding to Kaffon, kindly of-
fered to take him under his ptotection. They accordingly
fet out together, and, after a journey of two days, troffed
the river Senegal at Kayee, the frontier village of the king
of Kaffon’s dominions, near which that river ceafes to be
navigable, From Kayee Mr. Park was led by his. friendly
conductor to Teefee, the place of his abode, and the refi-
dence of the king’s brother Tigetee-Sego, an old man of a

Wen, 1.) 4): @) venerable

a

194 Mr. Park's Journey into Africa.

_ venerable afpeét, but of a felfith difpofition. He had never
feen, he faid, but one white man before, and, on deferibing
him, it was known to be Major Houghton. The circum-
fiance of having a white man under his roof was highly
gratifying to the vanity of Tigetee-Sego, on account of the
“great number of the nativés who reforted to fee him: He
therefore compelled our traveller to remain with him twelye
days, and afterwards to take a journey of two days more to
prefent himfelf to the king at his capital of Kooniakary,
who detained him another fortnight, but in other refpeéts
' behaved to him with great kindnefs and hofpitality. Of this
prince, whofe name was Demba Sego Jalla, Mr. Park re-
‘ceived the firft certain account of Major Hougliton’s death.

Being permitted at length to leave the capital, Mr. Park
profecuted his journey eaftward, and in five days arrived at
Kemnoo, a large and populous town (fince deftroyed), at that
time the metropolis of Kaarta. The fovereign, whofe name
was Dayfi Koorabarri, received Mr. Park with great kind-
~ nefs. Major Houghton was the only European he had ever
before feen, and he had conceived the higheft idea of the
fupériority of the whites to the blacks in all poffible refpects.
The language of the country feemed to Mr. Park to be a
mixture of the Mandingo and Sera-Woolli: but the pure
Mandingo, in the attainment of which Mf. Park by this
time had made confiderable proficiericy, was very generally
underftood, and with very little affiftance from his inter-
preter he found no difficulty in conveying his own fenti-
ments, and comprehending others.

Having informed the king that he propofed going to Bam+
bara in fearch of the Joliba river, which was believed to take
its conrfe through the centre of that extenfive kingdom, he
was told that, the Bambarans being at that time in a ftate of
warfare with the Kaartans, he could not without extreme
perfonal danger venture into the Bambaran country. His
only fafe route was a northerly courfe to Ludamar, a terri-
tory of the Moors in alliance with Manfong the king of

y Bambare ;

a:

Mr. Park’s Journey into Africa. to 3
Bambata; from whence, paffing as a traveller from the
Moorifh country, he might venture, by a circuitous journey;
to Bambara. To this advice ie obliged to fubmit or
give np all thoughts of profecuting his journey in fearch of
the Niger, the king, as the latt proof of his } kindnefs, fent
eight horfemen to convey him in fafety to Jarra, the frontier
town of the Moors, w here he arrived on the 18th of Fee
bruary 1796. Inthe courfe of his j journey he pafled through
a village not far from Jara, called Simbing, from whence
Major Houghion wrote his laft difpatch with a pencil.

The territories which our traveller had hitherto explored;
being very generally clothed with native woods, prefented to
the eye the appearance of great uniforinity. in his ptogrefs
eaftward the country rofe into hills, and the foil varied to a
confiderable degree ; but wherever the land was cleared, great
natural fertility was oblerved. Bondow in particular may
ay be pronounced “a land flowing with milk and
Honey.” Both thefe articles, together with rice and Indian
corn of two or three fpecies, were to be obtained at a fmall
expence. Of their honey, the Pagan natives make ah in-
toxicating liquor, much like the mead of Europe. The
price of a fowl in Bondou was a button, or a {mall bit of am-
ber; goat’s fleth and muitton were proportionably cheap ; ;
and for fix or eight amber beads Mr. Park might at any time
have purchafed a bullock. The domeftic animals are nearly
the fame as in Eutope: the Guinea fowl and red partridge
abound in the fields ; and the woods furnifh a {mall fpecies of
antelope, of which the venifon is highly and defery edly prized:

Of the other wild animals in the Mandingo countries the
moft common are; the hyena, the panther, and the ele-
phant. But the natives of Africa have not yet acquired the

art of taming the laft-mentioned animal, notwithftanding

his ftrength and docility, fo as to render him fetviceable to
man; and when Mr. Patk told fome of them that this was
a&tually done in the countries of the Eaft, his auditors
laughed, and exclaimed, “ Tobaubc Sonnio ?? A wwhite man’s
02 ' jie!

196 Mr. Park's. Journey into Africa.
lie! —The negroes frequently find means to deftroy the wild
elephant with fire-arms; they hunt it principally for the
fake of its teeth, which they transfer in barter to thofe whe
fell them again to the Europeans.
_ The paftures of Bondou furnifh an excellent breed of
horfes, but the ufual beaft of burthen in all the negro terri-
tories is the afs. The application of animal labour to the
purpofe of agriculture is wholly unknown. The chief im-
plement ufed in hufbandry is the hoe, which varies in form
in different diftri@ts ; and the labour is untiverfally performed
by flaves. Befides the grains proper to tropical climates,
the Mandingoes cultivate in confiderable quantities ground-
nuts, yams, and pompions. They likewife raife cotton and
indigo, and have fufficient fkill to convert thefe ma-
terials into tolerably fine cloth of a rich blue colour: and
they make good foap from a mixture of groand-nuts and a
ley of wood-afhes.
~The town of Jarra, at which Mr. Park had now arrived,
is fituated in the kingdom of Ludamar, a Moorifh country,.
of which it is not known that any account has ever beer
given in any of the languages of Europe. The town itfelf is.
extenfive, and the houfes are built of clay and ftone inter-
mixed ; but the major part of the inhabitants are negroes
from the borders of the Southern States, who prefer a pre-
carious protection under the Moors, which they purchafe by
a tribute, to being continually expofed to their predatory
hoftilities. |
* During his ftay at Jarra, Mr. Park refided at the houfe of a
Slatee trader, named Daman, who was known to Dr. Laidley. -
By him Mr. Park was informed that he could proceed no
farther on his way to Bambara, without leave from Ali, the
Moorifh chief or king of the country, who was then en-
camped at a place called Benowm ; and that it was ab-
_ folutely neceffary that a prefent fhould accompany the appli-
cation by which permiffion was to be obtained. Mr. Park
therefore purchafed five garments of country cloth, by the
fale.

t ae ee ee

Ban? 125 ahaa

«

Mr. Park’s Journey ints Africa. NG Of
fale of one of his fowling-pieces. Daman undertook te
negotiate the bufinefs, and at the end of a fortnight permif-
fion arrived fram Benowm.

This permiffion was brought by one of Ali’s own flaves,
‘who faid he was ordered to ferve Mr. Park as a guide to
Bambara; and on the 27th of February -he took his depar-
ture from Jarra, accompanied by this dave, his own faithful
boy, and a negro belonging to Daman; the interpreter re-
fufing to proceed any farther.

On the third day after his departure from Jarra they
reached a large town called Deena; en entering which Mr.
Park was furrounded by many of the Moorifh inhabitants,
who haraffed him with fhouts of infult, fpit in his face, and
feized his baggage, which they robbed of what things they
fancied. He got refuge, at length, in the houfe of a negro ;
and after experiencing much difficulty in perfuading his at-
tendants to proceed any farther, he fet out on the fecond day
for Sampaka. Here he procured lodging at the houfe. of a
negro, who underftood the art of making gunpowder. The
nitre was obtained in confiderable quantities from the fwamps
or ponds, which are filled in the rainy feafon, and to which
the cattle refort in the heat of the day for coolnefs.. As the
water of thefe ponds is flowly exhaled by the fun, the nitre
appears in a white efllorefvence on the mud, and is carefully
fcraped off in the form of {mail cryftals. Sulphur is pur-
chafed of the Moors, and the feveral ingredients are blended
together in fuch proportions as experience has {hewn will
anfwer the purpofe; though the powder thus made js far
inferior to that of Europe. ~

On the morning of the 7th of March, Mr, Park had
reached a {mall village called Sami, within two days journey
of Goomba, the frontier town of Bambara; and was refiing
him/elf in the hut of a friendly negro, pleafed with the hopes
of being foon out of danger, when he was alarmed by the
arrival of two Moors, wha announced that they came by
order of Ali to convey him to the camp at Benowm, They

03 ) added,

498 My. Park's Journey into Africa.

added, that, if he confented to go with them peaceably, he
had nothing to fear: but that, if he refufed, they had orders
to carry him by force.

Finding entreaty and refiftance equally fruitlefs, for the
meffengers were joined by others, all of them armed, our
traveller, guarded by the Moors, and accompanied by the
negro boy (Daman’s negro having made his efcape on feeing
the Moors, and the flave fent by Ali having previoufly left
him on the road), fet out on the evening of the fame day
for the camp at Benowm, which after a diftreffing journey
they approached on the 12th. It prefented to the eye a
multitude of dirty-looking tents, fcattered without order
over a large {pace of ground ; and among the tents were feen
herds of camels, bullocks, and goats,

The arrival at the camp of a white man was no fconer
made known, than all the people who were drawing water

at the wells threw down their buckets, thofe in the tents _

mounted their horfes, and men, women and children came
running or galloping towards him. He foon found himfelf
frosted with fuch crowds that he could fearcely walk ;—
one pulled off his clothes—another took off his hat—a third
ftopped him to examine his waiftcoat buttons—and a fourth
called out “ La illa ill Aliabi, Mahomed rafowl Allabi *
and fignified in a threatening manner that he muft fhe
thefe words. He at length reached the tent of the king,
whom he found fitting upon a black leather cufhion, clip-
ping a few hairs from his upper lip, while a female attendant
held up a looking- glafs before him; there were many other
females in the tent. The king appeared to be an old man
ef the Arab caft, with a long white beard. He had a fullen
and indignant afpeé&, and looking at our traveller with at-
tention, enquired of the Moors if he could fpeak Arabic ;
but being anfwered in the negative, he appeared much fur-
prifed, and continued filent.

* There is no god but God, and Mahomet is.his prophet.”
The

Mr. Park’s Journey into Africas 199
The furrounding attendants, and particularly the ladies,

were far more curious and inquifitive. They afkedathou-. __

fand queftions, infpeéted every part of Mr. Park’s apparel, —
fearched his pockets, and obliged him to unbutton his waift-
coat and difplay the whitenefs of his fkin, &c. They even -
counted his toes and fingers, as if they doubted whether he
was in truth a human being. When the curiofity of the
ladies was in fome meafure fatisfied, he was conduéted to
the tent of Ali’s chief flave; into which however he was not
permitted to enter, nor allowed to touch any thing belonging
to it. He requefted fomething to eat, and fome boiled corn
with falt and water was at length fent him in a wooden
bowl; and a mat was fpread out on the fand before the tent,
en which he paffed the night, furrounded by the curious |
multitude. A hut was afterwards erected, in which he was
confined and ftriftly guarded.

Some time after a ludicrous circumftance took place,
which would not deferve attention did it not tend to throw
fome light on the national manners of the people among
whom our traveller refided. Hearing one morning the found
of drums, Mr. Park was informed that the noife was occa- ,
fioned by the celebration of a wedding in one of the neigh-
bouring tents. Soon after an old woman entered his hut
with a bow] in her hand, and fignified that fhe had broyght
him a prefent from the bride, Before he could recover from
the furprife occafioned by this meffage, the woman dif-
charged the gontents of the bowl full in his face. Mr.
Park finding that it was the fame fort of holy water as that
with which the prieft among the Hottentots is faid to he-
fprinkle a new-marrjed couple, he began to fufpe& that the
ald lady was a€tuated by mifchief or malice: but fhe gave
him ferioufly to underftand that it was a nuptial benediétian
from the bride’s own perfon, and which, on fuch occafions, —
is always received by the young unmarried Moors as a mark
ef diftinguifhed favour,

The Moorith ladies feemed indeed to commiferate his

04 condition,

Oy Mr. Park's Journey into Africa,

condition, and one of them once privately fent him a {mall
fupply .of meal.and milk; but their kindnefs extended no
farther. If they pitied his fituation, it is probable that they
dared not adminifter to his wants; and his diftrefs at length
became almoft infurmountable. He was allowed a fingle
meal of kou/cous, a preparation of boiled corn, once in twenty-
four hours. All his effeéts were taken from him, and he
was not even indulged with a change of linen out of the
few fhirts he had brought in his portmanteau: oppreffed at
the fame time with a burning fever, his fituation was truly
deplorable. “In this condition, from fun-rife to fun-fet,”’
fays he, ‘* was I obliged to fuffer with an unruffled counte-
nance the infults of the rudeft fayages on earth,

In eight or ten weeks, however, . circumftances occurred,
which, contrary to their firft appearance, changed our
traveller’s fituation for the better, and in the end produced
his deliverance. -In the war which prevailed between the
kings of Bambara and Kaarta, the Moors at firft took no
active part; but Ali having afterwards engaged to fend 209
horfe to the affiftance of the fugitive Kaartans, he became
panic-fruck at the approach of the king of Bambara towards
Fen wm: broke up his camp, and fixed his tent in a country
to the north. Mr. Park was compelled to follow him, and,
after a month’s confinement at the new camp, was led by
Ali to Jarra. At this place he had the mortification to fee
the poor boy who had attended him from the Gambia taken
from him, by Ali’s command, for the avowed purpofe of
being fold into flavery. After this cruel circumftance, and
the certain information which he received from Ah’s own
fon (a youth of ten years of age, who had conceived fome-
thing like friendthip for Park, or pity for his misfortunes), ;
that it was in’ contemplation to deprive Park himfelf of his -
life, or put out his eyes, he deternained rather to rifk perifh- f
ing in the woods, of hunger, or by the fury of the wild beafts,
than to remain any longer with a horde of faithlefs bar-
barians, whole tendereft mercies were cruelty, and from

whofe

.
Mr. Park’s Journey into Africa. 201

whofe caprice or fanaticifm he was in hourly danger of
deftrnction.

On the morning of the 1ft of July 1796, Mr. Park was fa '
fortunate as to break the bonds of his captivity. He had
contrived to procure at his departure his own horfe, faddle
. and bridle; a few articles of apparel, and alfo his pocket

_compafs. This Jaft he had concealed in the fand during his
confinement. He rode forwards the whole of the firft day
without ftopping. <I felt,” faid he, “ like one recovered
from ficknefs ; I breathed freer; I found unufual lightnefs
in my limbs. Even the defert looked pleafant ; and I dreaded
nothing but falling in with fome wandering parties of Moors,
who might convey me back to the land of thieves and mur-
derers, from which I had juft efcaped.”

The firft emotions of his mind fubfiding however into
fober refleftion, he foon found his condition to be very de-
plorable. His horfe grew tired, and he experienced the
torments of thirft raging beyond defcription. Whenever he
came to a tree, he climbed it in hopes of difcovering a water-
ing-place, but in vain; he chewed the leaves, but found they
were al] bitter, and afforded no relief. In a vaft wildernefs
of the African continent, without an attendant or guide, with-
out food and water, or the profpeét of procuring any; ina
country where the lion and panther prowling for their prey
are lefs to be apprehended than man, what fituation could
be more forlorn and dreadful? He proceeded onwards,
howeyer, direéting his route nearly ea{t-fouth-eaft, in the
view of reaching by the fhorteft courfe poffible a diftri& that
might afford him fhelter. A heavy rain about midnight -
enabled him to quench his burning thirft, by fpreading his
clothes on the ground and fucking the moifture out of them 5
and a muddy pool, which he found foon after, yielded relief
to his horfe. The reft af the night, and nearly the whole of
the enfuing day, neither water nor food was to be found =
and he mutt inevitably have perifhed, had he not fortunately
towards evening, lighted upon a few fcattered huts of fome
» Foulah

.
202 Mr. Park's Journey into Africa.

Foulah fhepherds, Perceiving an aged negro woman among
_ thofe who gazed at him with great earneftnefs, he tendered
her his pocket handkerchief, and requefted in exchange a
hittle corn to eat. She gave him a kind anfwer, invited him
to her hut, and immediately produced a large wooden bow]
of kou/cous ready prepared. She procured likewife fome corn
and water for the horfe*, Thofe only who have fuffered
fimilar mjfery can judge of his fenfibility at this unexpeéted
deliverance. But as the village belonged to the Moors, our
traveller had only a fhort time to reft. As he approached
the territories of the negroes, however, his apprehenfions
diminifhed, and his condition improved,

Procuring precarious fupport in this manner from the
charity of the moft wretched of human beings, Mr. Park
wandered for the fpace of fifteen days, {till however pro-
ceeding onwards in the accomplifhment of his miffion. At
length, in the morning of the fixteenth day, having been
joined by fome Mandingo negroes, who were travelling to
Sego, he had the inexpreffible fatisfaction to behold the great
object of his withes—the long-fought majeftic Niger glitter-
ing to the morning fun, as broad as the Thames at “Welt-

* It is worthy of remark, and highly to the credit of the female fex,
that Mr. Park feems inv ariably to have met with compaflion and relief
from women. This perfeétly accords with the account given by another
enterprifing traveller, Mr. Ledyard, who expreffes himfelf as follows :
“* T have always remarked that women in all countries are civil, obliging,
tender and humane ; that they are ever inclined to be gay and cheerful,
timorous and modeft ; and that they do not hefitate, like men, to perform
a generous action. In wandering over the barren plains of inbofpitable
Denmark 3 through hoxeft Sweden, and frozen Lapland, rude and churlife
Finland, unprincipled Ruffia, and the wide-[pread regions of the wandering
Yartar, if hungry, dry, cold, Wet or fick, the women have ever been
friendly to me, and uniformly fo: and to add to this virtue, fo worthy the
appellation of benevolence, thefe aétions have been performed in fo free
and fo kind a manner, that if I was dry I drank the fweeteft draught, and
if hungry I ate the coarfe morfel with a double relifh.” Epuir-

miner,

— | ne

$675 Le ee

t

Mr. Park’s Journey into Africa. 203

minfter, and flowing majeftically but flowly from weft to
eaft, through the middle of a very extenfive town, which his
fellow-travellers told him. was Sego, the capital of the great
kingdom of Bambara. His emotions at this fight were ex-
quifite, and it were unjuft not to give them in our traveller’s
own words: “ I haftened,”* fays he, “‘ to the brink of the
river, and, having drank of the water, lifted up my fervent
thanks in prayer to the Great Ruler of all things, for having
thus far crowned my endeavours with fuccels.”” —Unhappily,
he had yet to fuftain many fevere and bitter trials of his pa-
tience and fortitude.

Information of a confiderable river flowing through the
centre of Africa, between the latitudes of 15° and 20° north,
had been received at very early periods from different
quarters. At one time it was believed to be a part of the
Senegal. The Gambia had the fame honour afcribed to it
at another. But fufficient proof was afterwards obtained that
neither of thefe rivers was the Niger, and further enquiries
confirmed the ancient accounts of a ftream that was not only
of greater magnitude than either the Senegal or the Gambia,
but which flowed in a contrary direction; running not to the
weftward into the Atlantic, but from weft to eaft, to regions
unknown. The Moors defcribed it by the name of Nil il
Abeed, or the River of Slaves: the negroes beftowed on it
the appellation of Jo/zba, or the Great Waters.

Some doubt however ftil]l remained. It was urged that
the Moors might poflibly fpeak of one river, and the negroes
of another ; and the account of its direétion towards the _
eaft was received by our ableft geographers with much dif-
ficulty and hefitation. On both thefe points Mr. Park’s
teftimony is clear and decifive; the Moors, in his hearing,
uniformly called it Nil il Abeed; the inhabitants of Sego,
the Joliba; and that it flowed from weft to eaft, he had
ocular demonftration in a long and perilous ambulation of
fome hundred miles, which he afterwards made on its banks.
Thys therefore is all further queftion obviated concerning

: the

204 Analyfis of the Emerald of Peru.

the exiftence and direction of this great river; but its ter=
mination fill continues unknown.
[To be concluded in the naxt Number.)

AVI. Analy/is of the Emerald of Peru. By M. VavavueE-
LIN. From the Annales de Chimie, Vol. XXVF.

SEVERAL celebrated chemifts have already analyfed the
emerald ; but, as I am convinced that {cience is promoted
and individuals inftructed by repeating the labours of thofe
who have preceded us, I have again fubjected this foffil to a
chemical analyfis. Klaproth, one of the moft accurate ana-
lyfets of modern times, found in the emerald of Peru filiceous
earth 66.25, alumine 31.25, oxyde of iron 0.50. It will be
feen in the courfe of this fhort memoir, that the refult of my
Jabour differs from that of the Pruffian chemift, not only in
the proportion of the conftituent principles, but in their
number, and the nature of fome of them*.

Exp. 1. This ftone, broken into fmall fragments, and ex-
pofed to a ftrong heat, loft a part of its beautiful green co-
~ Jour, and retained only a light fhade of it. In many places of
it there were cracks; and it loft of its weight 0.02 grains.

Exp. Il. Two hundred parts of this foffil, which anfwered
to 200 grains, poid de marc (eight ounces to the pound), or
10.615 grammes, were melted for an hour in a filver cru-
cible with 600 parts of cauftic potafh. The matter-had then
a greenith yellow colour. This folution, when evaporated
to a quarter of its bulk, was converted into a green jelly,
the fhade of which was much weakened by deficcation.

The refidue was diluted in a large quantity of water ; and
it was obferved, that the firft portions of this liquid, poured

* According to the firft analvfis of the emerald, the refults of which I
prefented to the National Inftitute, I found in it filiceous earth, alumine,
lime, and the oxyde of chrome ; but fince that epcch, having difcovered a
pew earth in the beryl, or aigue marine, I repeated my analyfis, under this
new point of view, and I found allo that particular earth, as will be feen
in the courfe of this memoir.

upon

Analyfis of the Emerald of Peru. 205

upon the fubftance, made it affume a bright and very agree~
able green colour. The folution of the falt had alfo the fame
fhade, but weaker. There remained a white infipid fub-
ftance, full of grains, which was infoluble in water, and had
all the properties of filiceous earth. It weighed 129 parts,
after having been expofed to a red heat.

Exp. IL. To the liquor of the fecond experiment, from
which the filiceous earth had been feparated, I added cauftie
potafh, more than neceflary for faturation, and then boiled
it for fome time. The greater part of the matter precipi-
tated was at firft re-diflolved; but there remained a certain
quantity which obftinately refified folution. The folution
having been filtered, the infoluble matter, which, when wafh-
ed and dried, weighed feven parts, was collected on the filter.

This matter had a light lilae colour, which became green
by the heat of the blow-pipe. When melted with borax and
_ the fufible falt of urine, it gave them a fuperb green colour,
perfectly like that of the emerald. This property of thus
giving a green colour to borax and microcofmic falt, made
me abandon the idea I had firft conceived, that this matter
might be the oxyde of nickel ; fince the oxyde of that metal,
though green, communicates to borax a hyacinth colour. As
this colour had a perfeé&t refemblance to that which I ob=
tained from the oxyde of the metal* contained in the red lead
of Siberia, I directed my experiments with a view to efta-
blith that refemblance. I therefore took this colouring mat-
ter, drawn from the emerald, and boiled it to drynefs with
concentrated nitric acid. I then poured upon the refidue,
eauftic potafh, and obtained a folution of an orange-yellow
colour; which when mixed with a folution of the nitrate of
_ lead immediately produced the red lead of Siberia, and gave,
with the nitrate of mercury, a precipitate of a vermilion red
eolour, abfolutely in the fame manner as does the acid of the.
red lead. i

“© Vauquelin’s account of this new metal, called Chrome, will be given
“mournext number, Ep:rt,
owe: Thefe

206 Analyfis of the Emerald of Perk:

Thefe experiments, though not numerous, are fufficient 6
prove, that the colouring matter of the emerald of Peru is
not iron, as announced by Klaproth, but that it is, on the
other hand, the oxyde of the new metal which I difcovered
in the red lead of Siberia. One thing, however, which ought
to furprife thofe acquainted with the fagacity and accuracy
which the chemift of Berlin fhews in his labours, and which
have gaitied him fo high reputation, is, that he did not ob-
ferve this fubftancé, fo eafily to be diftinguifhed by a great
number of characterifing maiks, eritirely different from thofe
exhibited by other minerals. I {hall now proceed to other
principles of the emerald.

Exp. IV. The reader will recollect that the liquor of the
fecond experiment, deprived of its filiceous earth, was pre-
cipitated by cauttic potafh, and that the precipitate was, in
great part, re-diflolved by an exeefs of this alkah. This
folution was then fuperfaturated with the muriatic acid, and »
carbonate of potafh ufed im commerce was poured over it:
This produced a very abundant precipitate, which, being
wafhed, and expofed to a.red heat ima filver crticible, weigh-
ed fifty-four parts.

Thefe fifty-four parts were diffolved in the fulphuric acid ;
and the folution; by the addiiion of a little potafh at intervals,
gave, by feveral fucceflive cryftallifations, 149 parts of alumi
eryftallifed in oétaedra; among which there were eight of
nine parts of the fulphate of lime ; but as thefe 140 parts of
alum contained only about twenty-fix parts of pure alumine,
and as the mother-water, the tafte of which was exceedingly
faccharine, gave no more alum by the addition of a new
quantity of potafh, I diluted it in water, and mixed with it
a folution of the carbonate of ammoniac, untt! there was an
excefs. I fhook this mixture from time to time, for feveral
hours; at the end of which the greater part of the hi
tate, which had been at firft formed, was diffolved,

I then filtered the liquor, and collected on the paper the un-
diffolved matter, which, when wathed and dried, weighed

two

Analy/is of thé Emérald of Peru. 20%
two parts, and exhibited all the properties of dlumine. The
liquor, being expofed to the aétion of fire, depofited, fome
moments after, a white infipid duft, full of grains, which

" diffolved with an effervefcence inacids. Being colleGted with
eare, wafhed, and made red-hot, it weighed twenty-fix parts.
This fubftanee, fubjected to different tefts, exhibited all the
charaéterifing marks of that earth which I found in the be-
tyl; the properties of which I explained at large in a me=
moir inferted in the preceding number of the Annales, and
which has obtained the name of Glucine:

It appears from the experiments announced in the courfe

of this analyfis, that 100 parts of the emerald of Peru con-
fift of

rit, Siliceous earth = “ - 64.60
2d, Alumine - - - = 14.00
3d, The particular earth, or g/ucine - 13.00
4th, Lime - - - 2.56
th, The oxyde of chrome - - 3.50
6th, Moifture, or other volatile matter 4 2.09

99-66

it appéars then by the refult of this analyfis, that there is 4
very great difference between the proportion, the number,
and the nature of the principles which conftitute the eme-
rald, and thofe found by Klaproth; fince, according to him,
it is compofed of only 66.25 of filiceous earthy 31.25 alu-
mine, and o.50 of the oxyde of iron. There are in this ftone
then three fub{ftances not obferved by the above chemift, viz.
glucine, the oxyde of chromé, and lime; while the oxyde of
iron, which he announces, does not exift in it.

It follows therefore from this refult, that the emerald and:
the beryl are two ftones perfetly fimilar, and compofed of
the fame principles, the colouring matter excepted; and
' 4anineralogy had already got the ftart of chemiftry by brisig-

7 ing

208 Curfary View of —
ing together thefe two foffils, and making them only oné

fpecies *.

XVIL. Curfory View of fome of the late Difcaveries in Sciences

[Continued from the laft Number, p. 65. ]
METEOROLOG Y.

Merrorotocy, which depends only on an immenfe
number of obfervations, has, however, been exalted into a
feience. It affords general refults of great importance; a
colleG&tion of which has been made by Cotte. By thefe it ap- -
pears that the barometer varies very little under the equator.
Its variation becomes greater in proportion as it approaches
the poles: It feems to experience a diurnal and an annual
variation.

Diurnal variation —Between the hours of ten and two,
both of the day and the night, the rifings and fallings of the
mercury are the leaft. The contrary takes place between
the hours of fix and ten of the morning and evening. This
feems to depend on the fun and the moon paffing the zenith.

Annual variation —The ofcillations are lefs in fummer,
greater in winter, and very great at the equinoxes. This
feems to depend, like the tides and the winds, on the fame
action of the fun and the moon.

Thermometers.—The mean degrees of heat are almoft the
fame in all latitudes. Kirwan has given a table for caleu-.. -
lating the mean degrees of heat in different latitudes.

_ Rains are more frequent in winter than in fummer; more
abundant in fummer than in winter. Mean quantity of rain
at Paris twenty-two inches. . The evaporation generally ex-
ceeds the rain at Paris. The mean evaporation is thirty-
three inches. ae

Aurora borealis is more frequent about the time of the
equinoxes than at any other feafon. This phenomenon is

+ -
.

%* See Abbé Haiiy on Cryftallifation.
almoft

Some of the late Difcoveries in Science. £09

almoft continual, in winter in the polar regions. For fome
years, paft it feems in our climates to have become lefs
frequent.

' Lunar period of nineteen years.—lt appears that the genes
ral temperature of a year returns the fame every nineteen
years, an epoch when the phafes and pofition of the moon,
in regard to the earth, are alfo the fame. From the above
peiod, therefore, we may predict, very nearly; the temp@ra-
ture of any given year. ‘This method is practifed by the
makers of almanacks; and their predictions, toa certain de-
gree, may bedependedion. This mode of calculation is well
known alfo to merchants who fpeculate in the price of pro-
vifions.

Maurice at Geneva makes meteorological obfervations of
the utmott importance, becaufe he has thermometers placed
at different heights above the furface of the earth, as Pictet
had formerly, and others at the depth of four feet below it.
He gives an account, therefore, of the evaporation of the
earth, eleGtricity, humidity, &c. His cbfervations appear
every month in an excellent colleétion, publifhed by the
brothers Piet, under the title’of Bibliotheque Britannique:
It appears that the thermometer, which is four feet below the
earth, ftands generally between g° and 10° Reaum. (52° and
54° Fahr.) and that it experiences very little variation.

Zoo.ocy.—Great attention has been paid to the natural
hiftory of animals. Cuvier has publifhed a number of me+
moirs on zoology, and fome have been publithed alfo by
Geoffroy. Daubenton propofes to divide the animal king-
dom into eight clafies :-—1f, viviparous gnadrupeds, of
which he reckons 415 ; 2d, cetaceous animals 15; 3d, birds
2,424; all thefe animals have two ventricles in the heart +
4th, oviparous quadrupeds, of which he reckons 11335 5th,
ferpents 1753; 6th, fithes 866; all thefe animals have only
one ventricle in the heart, and their blood is almoft cold:
nth, infeéts, of which he reckons 15,000; their heart is of

Vou. 1, P different

416 Curfory View of

different forms; their blood is white ; they have trache,
and breathe by fiemata : Sth, worms, of which he reckons
1,159 their heart is of different forms, their blood is white,
and they have no apparent entrance for the air.

«Cuvier and Geoffroy have made feveral interefting re-
fearches in regard to that clafs of animals called mammalia.
The former, in a memoir on the rhinoceros, has proved that
the-two kinds known by Camper, viz. that of Afia and that
of Africa, may haye one, two, or three horns. The horns,
therefore, cannot be a charaéterifing mark to diftinguith
them. The diftinguifhing mark, however, of the African
rhinoceros is, that it has only twenty-eight dentes molares,
while that of Afia has twenty-eight molares and fix incifores.
‘He is of opinion allo, that there are at leaft two other f{pe-
cies in exiftence, and perhaps a third.

, Camper has proved alfo, that the African elephant is dif~
ferent from that of Afia. ‘The tecth of the latter are com-
poted of tranfverfal zones, and thofe of the African elephant
reprefent on thew furface a kind of trefoils or lozenges. It
appears, that befides thefe two {pecies there exift two others,
and perhaps three. Swediaur fays, that the greater part of
the elephants’ tufks ufed in commerce are collected in the
immenfe paftures of Africa, where thefe animals feed, and
that the negroes fet fire to. the meadows in order to difcover
them. :

. Audibert propofes to give a hiftory of apes. He has al-
pp publifhed one number, containing fix coloured plates,
foho fize.

‘Birds.—Le Vaillant has already publifhed a part of his
Natural Hijflory of the Birds of Africa, confifting of five num-
‘bers, each containing fix coloured plates, in folio and quarto.
He has, announced that the whole work will contain 600
plates. An éditionin twelves, with fome plates, will ap--
pear alfo. The two firft volumes will be publifhed without
delay. He reipropples, to give a complete hiftory of birds.

St j Fifhes,
s 5 .

fome of the late Difcoveries in Scierite. ait

Fifbes.—Bloch has publifhed the laft fix volumes of his
beautiful work on fifhes. They contain, like the former fix,
216 plates, on feveral of which are reprefented fromm two to
three fubjects. He has been obliged to make feveral new
genera. This is one of the moft beautiful works that ever
appeared on ichthyology.

Lacepede is preparing a large work on the fame fubjec:
He has fhewn that the anableps, a fifh ‘hitherto believed to
have had four eyes, has in reality only two ; but each of its
eyes has two cornez, two cavities for the aqueous humour,
two irides, two pupils, but only one cryftalline humour
Different naturalifts have publifhed feparate memoirs on
fome particular kinds of fifh, and their different parts:
Herbft has publifhed at Berlin a very beautiful work on
crabs, with coloured plates.

Infeés.—This part of natural hiftory is become almoft as
immenfe as botany. Brogniard continues his fuperb collec-
tion of the butterflies of Europe. Fabricius‘has given a new
edition of his Entomologia Syftematica, emendata et au€ia.
LatreiJle has publifhed his Genera of Infecis, and D’ Anthoine
has publifhed an excellent memoir on the cynips (gall infect)
of the oak. Bofc has defcribed fome other fpecies of the
cynips, and Luce has defcribed a phofphorefcent beetle,
found near De Grafle,

Panzer is now publifhing a work on the infects of Ger-
many, entitled Fauna Infectorum Germaniz, printed at Nu-
remberg. He has publithed alfo a hiftory of the infects of
America. Raeufchel has printed awork at Leipfic, entitled
Nomenclator Entomologicus emendatus. Hedwig has given a
new edition of the Fauna /iftens InfeGa, by Roffi; in which
are defcribed the infects found in the neighbourhood of Flo-
rence ‘and Pifa. Martin has publifhed the Infects of Eng-
land. This work, like that on fhells, is executed in a maf-
terly manner.

Polypiers.—There are certain fubftances which are neither
animals nor yegetables, called polypiers ; fuch as coral, coral«

P 2 lines,

a12 Biographical Memoirs of P. Bayen.

lines, madrepores, &c. Girod Chantram has carefully ex-
amined fome of thefe fubftances, which had hitherto been
claffled among the eryptogamia kind of plants: fuch as the
byffus, conferva, ulva, tremella, &c.; and obferved, that
the greater part of them are compofed of tubes or veffels, in

which beings that appear to be animated circulate, He |
even diftinguifhed in one fpecies of conferva a real volvox, .

which had fome fimilarity to the ro‘ator of Gmelin.

- Thefe fuppofed plants, by a chemical analyfis, give the
fame refults as animal fub{ftances, He therefore coneludes
that they are not plants, but fpecies of polypiers, formed, like
coral, by fmall animals. Of thefe polypiers he diftinguifhes
two kinds; fome without tubes, and fome which have tubes,
We fhall then have three orders of polypzers :—1ft, The
caleareous, fuch as corals and madrepores; the fubftance of
which is hard and caleareous:—2d, Corallines, the fubftance
of which is foft and flexible, like {ponge :—3d, The conferve,
the fubflance of which is abfolutely herbaceous. It is to be
wifhed that naturalifts would pay attention to the ftudy of
the infe&ts which conftru& thefe different kinds of polypiers,
as they are full unknown.

An be continued.)}

XVIII. Beinabors Memoirs of Peter Bayen. By M. Lassus,
Secretary to the Cla/s of the Phyfical Sciences in the French
Nat. Infiitute. From the Annales de Chimie, Vol, XXVI.

Pp ETER BAYEN, member of the National Inftitute in the
fe&tion of chemiftry, was born at Chalons in the department
of la Marne, in the year 1725. His parents, obferving that
he had a happy difpofi tion for learning, took the earlieft op-
portunity to improve it, by fending him to the college of
Troyes, where he ftudied the Latin language with the beft

fuccefs. Having terminated the courfe of his ftudies at _
that place, he turned his attention to natural philofophy,

and, after acquiring the firft principles of chemiftry, foon
became

Biographical Memoirs of P. Bayen: az
Became fenfible that; to make any real progrefs in that feience,
the foundeft judgment muft be guided by a particular kind
of knowledge not fupplied by nature, and which can be ob-
tained only by long and affiduous labour. :

With a tolerable ftock of knowledge, and a defire to ob-
tain more, Bayen repaired to Paris, where he refided with

an eminent apothecary, a friend of the celebrated Charras.
The intelligence and happy difpofitions of the pupil could
not efcape the penetration of the mafter, who, finding in
this young man, fond of fcience, a character and tafte fimi-
lar to his own, treated him as his friend rather than a pupil,
and procured him every means of inftruction, by entrufting
him with the management of his laboratory. His hopes
were not difappointed: Bayen applied for feveral years to
all the labours of pharmacy, and acquired fo much fkill i in
this art, that, before he had attained to the age of thirty, he
was appointed chief apothecary to the army in Germany
during the'war of feven years. The duties of this office he
difeharged with a fuccefs worthy of the confidence which
had been repofed in him; and he fought no other recom-
penfe for the fatigues he underwent, than the fatisfaction of
being ufeful in the hofpitals.

After the peace he returned to Paris. At that period
government was defirous of executing a plan it had been
long meditating, which was, to caufe an analyfis to be made
of all the mineral waters common in France. Rouelle, be-
ing appointed to make choice of the chemifts capable of dif-
charging that tafk, pointed out Bayen and Venel. They at
firft carried on their labours in conjunétion, and publifhed
the refult of their obfervations; but as an enterprife of this
nature, to be completed, would require feveral years, and as
particular circumftances obliged Venel to difcontinue it, the
whole devolved upon Bayen, who applied himfelf to it with

the utmoft affiduity.

He fucceffively publifhed various works, which contained
much more extenfive information refpecting thefe mineral
P3 waters

ard Biographical Memoirs of P. Bayen.
waters than had ever been before known. The waters which:
he in particular analyfed were thofe of Barreges, Bagneres,
and Luchon. The analyfis of the latter is a model of correét-
nefs which ought to be followed in works of this nature,
and to which nothing could be added. This work, written
in avery methodical manner, while it inftructs the chemift
and the phyfician, may be ufefnl alfo to the naturalift and the
philofopher, and even to the man of letters, by the intereft
which the author gives to a fubje¢t that appears to be little
fufceptible of it, and the varicty of the details which it con-
‘tains, It is to be withed that this grand enterprife, begun
by Bayen and Venel, had been continued; but the funds fet
apart for the execution of it having been applied to other
objects, it was at laft dropped; and the knowledge refpeéting
the mineral waters of France is {till imperfe¢t.

Bayen, in the courfe of his travels through the Pyrenees,
had fiudied natural hiftory, and been convinced of the necef-
fity of analyfing bodies, in order to acquire a knowledge of
the fubftances which compofe them. He therefore collected
fpecimens of thofe minerals which feemed to be mott de-
ferving of particular attention; and thefe fpecimens in his
hands became valuable materials for the ingenious analyfis
which he made of them, and in which he was employed for
twelve years. To this immenfe labour the public is in-
debted for Bayen’s different memairs on marble, ferpentines,
torphyry, ophites, granites, jafper, argillaceous fchifs, and
the {parry ore of iron, which he prefented to the Academy
of Sciences, and which that body caufed to be inferted among
thofe of the foreign literati.

Stahl, the oracle of chemiftry; having maintained that one
of the effential principles in nature 1s pure fire, or the mat-
ter which produces fire in combuftible bodies, gave to this
element thus combined the particular name of phlogifion, or
the inflammable principle. Bayen, who in all his operations
fought only for truth, and would not be convinced without
evident proofs, becaufe the habit of experience had rendered
him miftruftful, began to doubt of the exiftence of phlogif-

ton,

Biographical Memoirs of P. Bayens 35
ton. He at firft communicated his doubts to fome. friends,
and then to the celebrated. Macquer, who did not approve
of them. The opinion of that learned man did not, how-
ever difcourage him ; and he continued his refearches..,. .It
was chiefly by examining precipitates of mercury that Bayen
convinced himfelf fully of the falfity of Stahl’s doétrine, and
that he acquired a proof that every thing called metallic oxyde
is indebted for the excefs of its weight, its colour, and its
ftate, only to the abforption of one of the conftituent parts
of the atmofpheric air. With apparatus, which he invented,
he made experiments fo rigoroufly correct, that he was able
to calculate the weight of this fubflance fixed in the metals.

When Bayen prefentec to the Academy of Sciences the
refult of the experiments above mentioned, Lavoifier, who
was prefent, made metallic oxydes the object of his re-
fearches-alfo. He repeated the experiments of Bayen ; found
them corre€t; difcovered that a portion of the air drawn
from metallic calces is much purer than that of the atmo-
{phere ; that this portion is the only part which can ferve
for combuftion and refpiration; and gave to this fluid the
name of vital air. Lavoifier therefore, by removing entirely
the veil which Bayen had only drawn a little afide, over-
turned for ever the theory of Stahl, and eftablifhed one of
the moft memorable epochs in chemilftry.

The various experiments which Bayen made, in the courfe
of three years, on the precipitates of mercury, led him to a
difcovery of the fingular property which fome of thefe pre-
cipitates have of exploding with a loud noife, when mixed
with a very {mall quantity of the flowers of fulphur. Bayen’s
Jabours alfo in regard to tin ought not to be pafled over in
filence, It was a queftion in chemiftry, to determine whether
that metal really contained arfenic, as Mareraff and Henkel
had faid; and, fuppofing it did, whether the quantity would
be fufficient to make the ufe of it be abandoned in economi-
cal purpofes. The long and laborious refearches of Bayen
difcovered that there exifts tin without any mixtufe; and

P4 that

ars Bingraphica? Membirs of P. Bayen.
that there exifts fomeé alfo, which is united to a very fmall
‘quantity of the arfenical fubfance.

His analyfes taught him alfo, that the tin ufed in orth.
, Merce, and that manufactured by pewterers, contain copper
and antimony, which render it hard; zinc, which gives it
a white colour; bifmuth, which renders it fonorous; and,
abave all, lead, which diminithes its value. It is in particular
this metal fraudulently united with tin, that can render the
Jatter dangerous *, as both thefe fubftances are foluble in
vegetable acids. Scarcely had Bayen’s refearches on tin been
wiade public, when the uneafinefs excited by Margraff and
Henkel vanifhed. It was clearly proved, that the very {mall
quantity of arfenic contained in tin cannot abfolutely be
hurtful, and no more ideas were entertained of banifhing a
fpecies of veffels fo long employed by our anceftors.

Bayen had fuch a habit of confidering objeéts, and of
judging of their compofition by the analyfes he had made of
analogous objects, that it was often fufficient for him to fee
and to touch them in order to tell their nature. As a proof
of this affertion, may be mentioned the opinion which he.
gave of one of the marble baluftrades in the Fluce de la Revo-
lution. Notwithftanding the polifh and apparent folidity of
this marble, he foretold that it would decay in a very little
time; and he pointed out to Deyeux, who was prefent, the
different places where the alteration would firft manifeft it-
felf, and thofe which would endure the longeft. Scarcely
had a year elapfed when the prediétion began to be accom-

plithed ; and in lefs than three years the alteration was fo-

gteat, that cenfiderable excavations were formed in the
places pointed out. Bayen was of opinion, that the monu-

’
* The pewter pots in common ufe in London contain lead in their
eompofition; and as all the beer drawn in them is more or lefs acid

(feale), ‘¢ is evident that thofe who ufe them are conftantly taking, though

in fall quantities, a foluticn of lead, which is highly noxious. It is.
very improper, therefore, to-ufe beer which has fiood in them for any
kength of time, Err. c

taents

.

— oS
a ee I

a

Biographical Memoirs of P. Bayen. 217
ments which have fubfifted without any perceptible altera-
tion for a long feries of ages, have been thofe conftructed
of marble, little fufceptible of any attack from the ation of
the air or of water. From all the analyfes which he made
of marble bélonging to ancient monuments, he concluded,
that when a public edifice is to be erected, an archite& can-
not take too many precautions to be affured of the good ftate
of the materials he employs, efpecially when they are brought
from a quarry recently opened. By thus making an ufefui
application of chemiftry to an art which feemed to be foreign
to it, he revived a truth, too little noticed, that there exifts
between all the fciences a connection which unites them by
fixed and invariable principles.

Befides the labours above mentioned, Bayen began others,
which, on account of the many experiments neceflary before
he could obtain certain refults, were never finifhed; for he
was of opinion that the operations of chemiftry ought to be
conduéted flowly, like thofe of nature. On this account he
has been known to employ himfelf whole years in the ex-

amination of one fubftance, in which he withed to dif-
cover and to feparate a matter, that would have been de-
ftroyed or altered by too violent means, had he proceeded
with more hafte. To this prudent conduct was owing the
great perfection to which he always carried his labours;
and his accuracy was fo great, that he was never afraid of
feeing his experiments repeated by other chemitts.
~ This diligent and laborious man, when he had attained —
to the age of fixty, found his health, which had hitherto
been found and robutft, fenfibly impaired by a long and pain-
ful malady. Several journeys which he was obliged to
undertake, the lofs of fome friends, domeftic troubles, and
weaknefs brought on by his Jabours, haftened his death. He
fupported his complicated evils with great patience, and died
in the beginning of the prefent year, at the age of feventy-
two. Bayen lived in celibacy, but he poffefled the virtue
neceflary for that condition. He was a man of a found judg-

ment,

418 French National Inflitute. ~ |
ment, directed always by the force of reafon and experience,

In the diftribution of the places which he had at his difpofal,

when infpector of hofpitals with the army, he obferved the

moft impartial juftice; conferring them according to merit,

and inexorable even to folicitations from his relations or
friends. Chemiftry did not occupy the whole of his atten~

tion, and the variety of the knowledge which he had acquired

by his ftudies, rendered his conyerfation interefting and
agreeable.

INTELLIGENCE

AND

MISCELLANEOUS ARTICLES,

LEARNED SOCIETIES.

In the public fitting of the French National Inftitute, held
on the 15th of Meffidor (July 3), after an account had been
given of the labours of the preceding three months, Cit.
David Leroy read a memoir on the {mall hips of war of the
Ancients, which he examined from the time of the firft
Punic war to the battle of Actium. He made choice of this
epoch, as being that which prefented the moft remarkable
improvements, and refpecting which we have the moft in-
formation. The author, in this memoir, points out.the ad-
vantages of thefe veffels, which were exceedingly narrow in
proportion to their length, feveral of them being eight and!
even ten times Jonger than they were broad, which allowed
them, though pufhed forwards by oars alone, to advance with
great velocity. Cit. Leroi thinks that, notwithftanding the
improved fiate of navigation, oars ought not to be fo much
neglected; and that fhips of war like thofe ufed by the
Ancients might ftill, efpecially during calms, be attended
with great advantages, ; i

A friend

French. National Inflitute. 219

A friend read for Cit. Delambre, who was then engaged
near Carcaffonne in meafuring a degree of the meridian, an
account of the means employed to meafure, with the greateft
accyracy, a portion of an are between Melun and Lieufaint.

Cit. Fleurien communicated fome conjectures, perhaps
too hypothetical, on the manner in which the north-weft
coaft of America was peopled; together with a general view
of that coaft, and of both the Americas in regard to civiliza-
tion. This memoir difplays the extenfive Ietowielae of its
author,

Cit. Colin-Harleville recited a dialogue between a man
and his own confcience, Several traits of fentiment were
loudly applauded.

Cit. Chaptal communicated a memoir on yellow dyes, to
which it has been as yet found impoffible to give fplendour
and durability. The author pointed out the chemical means
to be employed for accomplithing this objeét; and took oc-
cafion to thew the great obligation which the arts have to
chemiftry.

Cit. Mongez prefented fome reflections on two antique
ftatues, the dying gladiator, and the gladiator repellens, or
fighting gladiator; which are now on their way to embel-
lith the Mufeum of Antiques, and of which_ beautiful
copies in bronze may be feen at the entrance of the court of
the Tuilleries. Cit. Mongez is of opinion that thefe two
Greck ftatues do not reprefent gladiators, who were known
only among the Romans, whom the people defpifed, and
who were, however, feen with pleafure—but rather Grecian
wreftlers. It is well known that the Greeks united in their
wrefilers, thofe ideas of dignity, ftrength and beauty, which

are feen imprinted on thefe beautiful ftatues.

Cit. Lalande, after remarking that the magnetic needle
does not point always exaétly to the pole, concludes from
feveral obfervations, which he communicated to the Aflem-
bly, that it direéts itfelf towards a certain place en the fur-
face of the earth, which he thinks approaches very near to

the

\

220 New Coinage.
the entrance of Baffin’s Bay on the northern coait of
America.

Cit. Molé read, for Cit. Andrieux, a tale in vente entitled
Le Doyen de Badajoz.

The Inftitute then adjudged the prize propofed the [Vth
year, the fubject of which was “ the conftruction of a
pocket time-piece proper for determining the longitude at
fea, &c.”

‘The National Inftitute at Paris has applied to the Direc-
tory for permiffion to convoke a deputation of the Literati of
all countries in amity with the French Republic, to eftablith
a uniformity of weights and meafures throughout the civi-
lized world.

A Society of Agriculture and Rural Economy, which has
already among its) members Creuze-la-Touche, Gilbert,
Thouin, Desfontaines, Dubois, Crette-Palluel, Teffier, Cha-
bert, &c. has been eftablifhed at Paris. As this fociety will
hold public meetings, the information it muft diffufe in its
memoirs will no doubt tend greatly to ameliorate the ftate of
aericulture, and to improve this ufeful art.

On the evening of the 17th inft. the Members of the
Royal Academy of London, by defire of government, held a
meeting at Somerfet-houfe to confider of fome beautiful
éevice for our coin, which may render counterfeiting more
difficult, and imprefs foreigners with an idea of our national
tafte, The idea is good fo far as it goes, but it ought io go
farther. Our coinage ought to be fo managed as to ferve
for a real hiftorical feries and chronology of all important
public events, whether of a profperous or adverfe nature.
The Royal Society and Royal Academy would be ufefully
employed in producing the neceffary devices, Jegends, &c.
We fay ufefully, for we know of no means that could with
equal facility give fo much information to all ranks in the
community. The events recorded on our coins fhould not
be thofe only that are of a political nature: the era of ufeful .

inven-

Antiquities. —Dioptricks. 222
inventions, and the names of eminent benefa&tors of man-
kind, ought in this manner to be handed down to pofterity.

ANTIQUITIES.

A DIsTINGuIsnED Artift, who is travelling through the
fouthern departments of France, charged by government
with a miffion relative to the arts, in a letter dated Aix,
Prairial r4th, fays: “ Some workmen, who were digging up
the ground on the declivity of an eminence which overlooks
Vienne, difcovered a {mall group, confifting of two children
formed of white marble, in perfeét prefervation, and exceed-
ingly well executed ; one of the children holds a bird, which
the other endeavours to fnatch from it, and which feems to
peck the arm of the latter. Each of the children refts
againft the trunk of a tree. At the bottom of one of thefe
trunks, and near the child which holds the bird, is feen a
ferpent ; and on the other trunk there is a lizard having in
its mouth a butterfly.

DIOPTRICKS.

THE Abbé Hany, having polithed a fragment of tranf-
parent native fulphur, found that it pofleffes the power of
double refraction in a very eninent degree. The two faces
of this fragment are inclined to each other about twelve
degrees, and their greateft diftance is fourteen millimetres,
or a little more than fix lines. If this fragment be placed on
a piece of paper on which a line has been drawn, two very
difting& images of the line are feen. By obferving obje&s
fomewhat remote through this fragment, it may be judged,
by the diftance between the images, that the refra@ion of
fulphur in itfelf mut be very confiderable, allowance being
made for the denfity of that fubfiance, the {petifie weight of
which is only double that of water ; and this agrees with the
refults of Newton, in regard to’ the refractive powers of ine
flammable bodies. Cit, Hauy propofes to make experiments
in order to determine -the quantity of this refra&tion, which

4 has

222 Arts.

has not yet been meafured, and to compare it afterwards
with the refult of calculation, according to the proportion
between the refractive powers of inflammable fubftances and
their-denfities.

| ARTS.

AN ingenious Artift at Paris has lately completed, ath
great perfeverance, patience, and mathematical. accuracy,
a very curious model of that city, on which he has been
employed nine years. He has not contented himfelf with
comparing and correéting all the plans of Paris ever pub-
lithed: he meafured all the ftreets, {quares, &c. according to
the moft accurate geometrical methods of meafurement, and
determined the inequalities of the fite of that immenfe capi-
tal by levelling. The greateft diameter of his model, in the
extent from eaft to weft, is fifteen feet. The mean fize of
the houfes is three lines. The artift has carried his accuracy
fo far, that each inhabitant of Paris can diftinguifh his own
houfe, court-yard, and garden. The public places and gar-
dens are reprefented with a moft ftriking fimilitude ; and not
only their dimenfions but their colour and ornaments can be
obferved. The alternate rifing and falling of the plane of
the model gives to this reprefentation a correctnels which
produces an effect like enchantment, if the obferver {up-
pofes himfelf to be ftanding on Mount-Marte, and to be
looking down on the city. The artift has with much judg-
ment endeavoured, by the fhades of his colours, to give a
point of reft to the eye; the want of which is a great failing
in that model of Rome which formerly ftood in the library
of St. Genevieve, and which now belongs to the french
nation, as it exhibits the tirefome view of a dazzling white
-mafs of gypfum. Thirty thoufand trees, which diftinguith
the different walks, public places, and gardens, form an
agreeable variety with the flated and tiled roofs. This model
may be taken to pieces by means of fcrews, and can be
packed into three large boxes for the purpofe of tran{porta-
ton.

ENGI-

sae

Engineering. 223

ENGINEERING.

A DIRECT communication between the counties of Kent
and Effex has been projected by Mr. Dodd, engineer, by
means which we think well calculated to anfwer the intended
purpofe, He propofes a cylindrical tunnel under the river
Thames, from Gravefend to Tilbury, to be conftructed
wholly with key-ftones, and therefore able to bear any pref-
fure; the diameter to be fixteen feet in the clear, which
Mr. Dodd imagines will be fufficient for foot, horfe, and
carriage-paflengers; the paflage to be illuminated with lamps,
and a fteam-engine to be ereéted in a proper fituation to
draw off the drainage water, if any fhould accumulate.

The expence of this ftupendous undertaking is eftimated

at fo low a fum as 15,9551. for goo yards of tunnelling, re-
laying the bottom, lamps, lamp-irons, fteam-engine, pipes,
and other neceflary machinery.
' This projected meafure will fave a circuitous route of
fifty miles by land (the diftance from Gravefend 1o Til-
bury, along London-Bridge). Independent of the advantage
it would afford to commercial eftablifhments and agricultu-
ral improvements, the general benefit to the counties of Kent
and Effex muft be immenfe.

Mr. Dodd is of opinion, that, whether the meafure is con-
fidered as a great national improvement, or a local one to
the two counties, of forming a military poft of the firft con-
fequence in that part of the kingdom, for enabling troops,
&c. to pafs through, its importance claims the greateft at-
tention. Another queftion he fuggefts, is, what may be the
moft proper method of raifing the fupplies to defray the ex-
pence of the undertaking—whether by the joint expence of
both counties, or by a fubfcription of private individuals, in-
corporated by Parliament, with authority to levy tolls? The
latter mode he is convinced would be beneficial to the indi-
viduals, and amply repay the fhare-holders.

The following are the eftimates of the expence, as fug-

gefted by Mr. Dodd, in the firft inftance ;
Te

224. Vegetation.
To goo yards (running meafure) of tunnelling, including exe
cavations, vaulting with key-ftones, &c, at 12). per

yard, - - - £10,800
To re-laying the bottom with new-made ground,

900 yards, at 11. each, - - ~ dnocgeeaee
To placing lamps and lamp-irons through the tun- be

nel, collectors’ rooms, and gates at each end, - 400
To making good the entrance roads at each end of

the tunnel, - - - - 160
To a fteam-engine to draw off drainage-water, - 1,780
Neceflary machinery during the execution, ~ 50

To ten per cent, upon the whole, for contingencies, 1,415

Total — L 155958
VEGETATION.

IN our firft number (page 109) we ftated that, from fome
interefting experiments which had been recently made by
_ Sir Francis Ford, it had been proved that plants fprinkled

with water, previoufly impregnated with oxygen gas, grew
much more vigoroufly, and difplayed more beautiful tints,
than thofe nourifhed with common water. The application
of oxygen to promote vegetation has been fince tried in the
following fimple manner, and the refult has been the fame
as above ftated: Bottles filled with oxygen gas, ‘being firft
inverted, have had their mouths buried under ground, near
the roots of the plants intended to be fupplied with it,
After fome time the gas in the bottles was found reduced to
the ftandard of common atmofpheric air: but the oxygen
had done its duty; for the plants that had been thus fup-
plied with it were much more healthy and beautiful than
others of the fame kinds placed in every ’other refpeét in
fimilar circumftances.

Erratum, Page 192, line 13, for 42d. read 2d of December.

THE

‘ PHILOSOPHICAL MAGAZINE,

AUGUST 1708.

I. Decription of the large Orang Outang of Borneo. By
F. B. von Worms. From the Tranfactions of the Ba-
tavian Society in the Ifland of Java. 7

M ANKIND have beftowed every poffible pains to trace
out the progrefs of nature, and to difcover thofe threads
by which her works are conneéted ; and their exertions, in-
deed, have not always been fruitlefs. Thus, for example,
the difcovery of animal plants pointed out. the tranfition
from the vegetable to the animal kingdom. The bat and
the flying fquirrel difplayed the connection between qua-
drupeds and birds; and the feal and the fea-cow that of
quadrupeds with fifhes.

The greateft vacuity which appears to us in the aii of
nature is, certainly, that obferved between man, a being
endowed with reafon, and the irrational animals. Naturale
ifts hitherto have endeavoured, but in vain, by the moft ace
curate refearches to acquire fome fatisfaction on this point
and we may almoft confider it as certain that the links of
the great chain, here wanting g, are not to be found in the
world which we at prefent inhabit. Were nothing more

“ean but fimilarity of bodily conformation, this tranfi-

— Vou. 1. Q tion,

226 Defeription of the Orang Outang

tion, without doubt, would be found in the four-handed
“race of apes. But as the qualities of the mind are here as
much confidered as the form of the body, it is evident that
the ape, which does not defetve the fecond rank among the
irrational animals, cannot form the link that connects qua-
drupeds with man. ‘The external figure, however, of this
znimal has fince the earlic periods engaged the attention
of naturalifts ; and by the fimilitude of its body we are led
to fufpe& a fimilitude of mental powers in beings to which
the all-wife Creator has given fo much likenefs. But as the
difcoveries made by the fearchers into nature are frequent-
ly not fo much the truth as fomething fuited to the fyftems
which they have adopted, this circumftance has given rife to
@ great deal of error. The celebrated Linneus himfelf was
induced by a figure which Bontius * delineated of an orang
outang, or wild man, feen in the ifland of Java, and the ac-
counts of fome travellers, to clafs his homo nofurnus or night-
~ man between man and the ape, and thereby to eftablifh
the exiftence of a being, the truth of which is as yet very
doubtful.

Buffon proceeded in a much more cautious manner.
That celebrated naturalift fufpeéted, and not without rea-
fon, that the accounts given with fo little accuracy of the
night-men alluded only to the white negroes or kakerlaks,
confidered in a falfe light or under the veil of prejudice ;
and, indeed, the defcriptiow given by Bontius of the orang
outang differs only in fome .very inconfiderable circum-
ftances from the figure of the white negro or kakerlak
Saudami defcribed by M. van Iperen}. If we take from this
defcription of Bontius the ruff under the chin, and the few
hairs which cover the head, a more beautiful human form

* Bontius refided as a phyfician at Batavia in the laft century, and
wrote Hif?. Nat. et Med. Ind. Orient. Evit. re
+ Sce the fir part of the Tranfactions of the Batavian Society in the
Ifand of Fava. Pa
would

of the Iand of Borneo. 227

would appear than that of Saudami*; and had the latter
grown up, not at the court of the prince of Tabana, but in
the folitary woods of the ifland of Bali, his mental powers
would have been fo little expanded, that an inattentive ob-
ferver might have clafled him among the pongos, varis,
orang outangs, &c. of Battel, Pyrard, Leguat, and others.
But the figure which Bontius has given us of the orang ou-
tang may have been delineated with too great a refemblance
to that of man, and contraryto truth; for, if we adhere only
to the defcription, we can difcover nothing more than a
common large orang outang or pongo. Briffon, who claffes
the orang outang of Bontius along with the vari, appears to
have been of the fame opinion. An inftance of fuch a falfe
and too human-like reprefentation of this animal occurs alfo
in the figure of an orang outang of the ifland of Borneo,
given in Beckman’s voyage ; where the author {peaks, with-
out all doubt, of the fame fpecies as that tranfmitted to our
fociety from that ifland. But be this as it may, it is certain
that fince the time Bontius refided in Java, or the middle of
the laft century, no orang outang, fuch as that delineated
by him, has been found either in this ifland or in any of
thofe in the neighbourhood ; and as he afferts that he faw
feveral fuch animals of both fexes, it is certainly incompre-
henfible why the leaft traces of them are not now to be dif-
covered. The oldeft and moft experienced Javanefe are
acquainted with no other orang outangs than fuch as are
real apes; and they diftinguifh under this Malayan name

* «“ The defcription of the white iegro,” fays the author in his Lesters
from Indiay “ will afford a new and inconteftable proof to our naturalilts,
that every thing hitherto faid of whole races of Aakerlaks or white negro
night-men, and the like, is mere fables, and that fuch men are fom.»:mes
produced here and there only by accident. The parents of this white ne-
gro, who is called Saudami, were, like the other inhabitants of their native
country, the ifland of Bali, of a dark brown colour, and their fon was not
fickly, but large and ftrong. I found him to be five feet two inches and a
balf in height, Rhinlandifh meafure.” Eprr.

Q2 two

228 Defeription of the Orang Outang Bt
two kinds without tails, which Buffon places among the
pongos or jockos. Both are natives of Borneo, the only
place almoft where they are found ; and whatever travellers
may fay, they are as little to be feen in the forefts and wilds

of Java as the lions and elephants reprefented on fome charts ~

of that ifland. The {mall fpecies which Buffon, by abbre-
viating the Congo name, calls jocos, are often brought to
Java by fhips coming from Bangarei ; and of this kind was
that fent alive to Europe in 1776, and of which. an accu-
rate defeription has been given by Wofmaer. The orang
outang of the large kind, or the pongo of Buffon, is not
common even in its native country Borneo ; and much pains

and labour had been in vain employed for upwards of twen-_

ty years, in endeavouring to catch one of thefe ftrong and
mifchievous animals. M. Palm, the fefident at Rembang,
was at length fo fortunate, on occafion of his. being fent
on an important miflion to Sukkadana, to procure after a
great deal of trouble one of thefe animals, which he fent to
the Batavian Society preferved in arrack. The following
accurate defcription of it will, in my opinion, fhew how
fruitlefs it will be to fearch for the wild men of Bontius in
this {pecies of orang outang.

The head in a certain degree is fomewhat fharpened from
behind towards the top. The. mouth projets a little for-

wards, and on each cheek is a flefhy excrefcence (vieefachtige

kwabbe) which extends fidewife more than the thicknefs of

the head: The ears are mall, and lie flat to the head. The

eyes are fmall and prominent, ‘The nofe, without any per-

ceptible elevation, confifts merely of two long noftrils, placed

in an oblique direction towards each other. ‘The mouth is

furzounded by thick lips, and in the infide has no pouches

-(zacken). The tongue is thick and broad. On that of the
“animal in queftion there were found fome rémains of green
herbs which it had eaten. Each jaw is furnifhed before
with four broad incifors, ftanding between two thick canine
teeth, which rife above them. The face is of a dark brown
. colour,

of the Iftand of Borneo. 229
colour, and has no hair, except a very thin beard. The
neck is exceedingly fhort. The breaft is much broader than
the hips. At the rump there is no appearance of a tail, nor
of any tough projecting hide. The penis feems to be drawn
back into the body. The’hands are long, and the palms as
well as the fingers are of a dark brown colour, and have
no hair. The legs are fhort and thin, but the mufcles are ;
ftrong. The feet have a great refemblance to the hands.
The toes and fingers are furnifhed with black nails, almoft
like thofe of a man, except the large toes, which are fimaller
and fhorter; a difference that arifes perhaps from the fre-
quent ufe made of them. The breaft and ‘the belly are
moftly bare. The other parts of the body, the face, the
ears, the palms of the hands, the feet and the fingers ex-
| cepted, are covered with brown hair, which in many places
. js fully as long as the finger.

Under the fkin of the throat and breaft of the animal
tranfmitted to the fociety, there were found two bags, one

~ =

of which occupied the greater part of the breaft, and, as weil
as the fmaller which was inclofed in it, had a communi-
cation with the wind-pipe.. As this rare animal was "de-
ftined for the cabinet of the Prince of Orange, it was fub-
* jected’ to no- farther anatomical refearches, for fear of de-
ftroying its configuration. The bowels, to guard againft
corruption, were taken out before it had been tranfmitted
to Batavia. We, however, flatter ourfelves with, the well-
grounded hope of being able to give, at fome future’period,
a particular and accurate account of the properties, habits
and manner of living of this large orang outang, as the j ju-
_rifdi€tion of the Eaft India Company, under the prefent
government, has been fo confiderably extended in Borneo,
that accefs is now opened for us to the interior parts of that
great ifland*, With regard to the manner in which this

* In the fecond part of the Tranfactions of the Batavian Society there.
_ isa pretty circumf@antial defcription of this ifland, together wiih a fhort
extract from the journal of the above-mentioned M. Palm.

re, | pg / animal

4

230 Defcription of the Orang Outang

animal was caught, we were informed’ by M. Palm, that it
defended itfelf fo furioufly with fharp-pointed fticks, which
it‘broke off from the trees, that it was impofhble to take it
alive. This property it feems to poffefs in common with the
African pongos, which, as Beutel fays, attack elephants with
thefe weapons, and drive them from their places of refort*.

The following is an accurate meafurement of the different
parts of this animal, according to the Rhinlandic foot}
divided into twelve inches:

Whole length of the animal from the foles of the feet to
the crown of the head 3 feet 103 inches. This, however,
does not agree with the meafurement made in the ifland of
Borneo, where the whole length was found to be 49 inches ;
but perhaps a different ftandard was employed, or the body
of the animal might have become contraéted by lying in-
arrack. Circumference of the body at the fhoulders 3 feet
$ of aninch. Circumference of the body below the breaft
3 feet 34 inches. Circumference at the hips 2 feet 44 inches:
Aperture of the mouth 4% inches. Length or projection of
the muzzle 34 inches. Diftance from the middle of the
upper lip to the eyebrows 47 inches. Diftance between the
corners of the eyes 13 inch. Breadth of the eye the fame.
Diftance from the eyebrows to the hinder part of the head
62 inches. Diameter of the head from top to bottom 10%
inches. Diameter of the head acrofs, meafured at the
diftance of 33 inches from the top of the above line, 64
inches, Diameter of the head meafured as before, at the
diftance of 6; inches from the crown, 9} inches. External
circumference of the ear 33 inches. Circumference of the
ear below where it adheres to the head 3 inches. Height of
the ear 13 inch. Breadth ~ of an inch. Diftance from

* Ought not this property to procure to the orang outang the firft rank
among animals next to man? For, whatever Buffon may fay to the con-
trary, we know of no other animal which willingly employs for its defence
any weapons but thofe beftowed on it by nature.

+ The Rhinlandith is to the Englith foot as 1033 to 1000. It is there-

' fore equal to 12.396 Englith inches. Enir.
the

of the Iand of Borneo. ; 231

the fhare bone to the collar bone 2 feet = of an inch.
Diftance of the breaft bone from the fhare bone 1 foot Z of
an inch: Diftance between the nipples of the breaft 9
inches. Length of the arms to the tips of the fingers 3 feet
+ of an inch. Circumference of the arm at the fhoulder
a1 inches; in the middle 1 foot 3 of an inch;, at the elbow
a1 inches. Circumference of the fore part of the arm in
the middle 10% inches; at the hand 8t inches. Length of
the upper part of the arm I foot £ of an inch. ’ Length of
the lower part of the arm 1 foot 2; inches. Length of the
hand from the joint to the tip of the middle finger 93 inches.
Length of the thumb 3 inches; of the fecond finger 45
inches; of the middle finger 52 inches; of the fourth
finger 5; inches ; of the little finger 4; inches. Circum-
ference of the hand meafured at the root of the thumb 9%
inches; of the thumb and the three following fingers 33
inches; of the fifth finger 3; inches. Length of the palm
of the hand 5% inches. Breadth of the palm of the hand 42
inches. Thicknefsof the hand 1 inch. Length from the heel
to the upper end of the thigh bone 1 foot 8 inches, Length
of the thigh bone 1 foot 5; inches. Circumference of the thigh
1 foot 5+ inches. Length of the leg from the knee to the fole
of the foot 114 inches. Circumference of the leg clofe under
the knee 11 inches; at the middle of the leg 10% inches; at
the ancle roinches. Circumference of the foot where the large
toe begins 103 inches. Length of the great toe 25 inches ;

of the fecond toe 43 inches; of the third toe s inches;

of the fourth toe 42 inches; of the fifth toe 4} inches.
Breadth of the fole of the foot where the great toe begins 4
inches. Breadth of the fole of ‘the foot at the heel 3 inches.
Length of the fole from the heel to the beginning of the
toes 63 inches. Circumference of the great toe. 4 inches ;
of the three following toes 3% inches; of the fifth toe 33
inches. Width between the root of the great toe and the
root of the fecond toe 4 inches.

O 4 Il. O2-

~—

[ 232 J ‘

II. Odfervations on a fingular Phenomenon called the Speétre of
the Broken. By F. L. ForDAN. From Gottingifches
Journal der Naturwiffenfchaften, by F. F. Gmezin.
Vol. I. Part III. 1798.

i | ' the courfe of my repeated tours through the Harz*, I
afcended the Broken twelve different times; but I had the
good fortune only twice (both times about Whitfuntide) to
fee that atmofpheric phenomenon called the Spectre of the
Broken, which appears to me worthy of particular attention,
yas it muft, no doubt, be obferved on other high mountains
which have a fituation favourable for producing it.

The firit time I was deceived by this extraordinary phe-
nomenon I had clambered up to the fummit of the Broken,
very early in the morning, in order to wait there for the in-.
expreflibly beautiful view of the fun rifing in the eaft. The
heave its were already {treaked with red; the fun was juft
appearing above the horizon in full majefty, and the moft
petiect ferenity prevailed throughout the furrounding coun-
try, when the other Harz mountains in the fouth-weft, to-
wards the Worm mountains, &c. lyirig under the Broken,
began to be covered by thick clouds. Afcending at that’
moment the granite rocks called the Teufelskanzel, there ap- ©
peared before me, though at a great diftance, towards the
Worm mountains and the Achtermannshohe, the gigantic
figure of a man, as if ftanding on a large pedeftal. But
{carcely had 1 difcovered it when it began to difappear; the
clouds funk down fpeedily and expanded, and I faw the
phenomenon no more.

‘Lhe fecond time, however, I faw this {peétre fomewhat
more diftinétly, a little below the fummit of the Broken, and
near the Heinrichshéhe, as I was locking at the fun rifing
about four o’clock in the morning. The weather was ra-
ther tempeftuous ; the fky towards the level country was

* The Harz mountains are fituated in Hanover.

€ Lad
‘ : Pe eis a they
. . wy Mee

pretty . oo

-

Obfervations on a fingular Phenomenon. 233

* pretty clear, but the Harz mountains had attfadted feveral

- thick clouds, which had been hovering around them, and
which beginning'to fettle on the Broken confined the pro-
fpe&. In thefe clouds. foon after the mfing ‘of the fun, I
faw my own thadow, of a monttrous fize,' move itielf for a
couple of fecon s exaétly as I moved; but I was foon ine
volved in clouds, and the phenomenon difappeared.

Itis impoffible to fee this phenomenon, except when the
fun is.at fuch an altitude as to throw his rays upon ‘he body
in a horizontal direGtion ; for, if he is higher, the fhadow is
thrown rather under the body than before it.

Tn the month of September. lait year, as I was making a
tour through the Harz with a very agreeable party, and af-
cended the Broken, I found an excellent account and expla-
nation of this phenomenon, as feen by M. Haue on the 23d
of May 1797, in his:diary of an excurfion to that mountain.
‘thall therefore take the liberty of tranfcribing it. -** After
having been here for the thirtieth time,” fays M. Haue,
' and, befides other objects of my attention, having procur-
ed information refpeCting the above-mentioned atmofpherie
_ phenomenon, [ was at length fo fortunate as to have the
pleafure of fecing it; and perhaps my defcription may afford
fatistation to others who vilit the broken through curiofity.
The fun rofe about four o’clock, and, the’ atmofphere being
quie ferene towards the eaft, his rays could pafs without any
~ obftruétion over the Heinrichshohe. In the fouth-weft, how-
ever, towards Achtermannshéhe, a brifk weft wind carried -
-bejore it thin tranf,arent vapours, which were not yet cons
Re denfed i into thick heavy clouds.
___, About a quarter Patt four I went towards the ifin, and

“ eto. have a free profpeé&t to ihe fouth-welk 5 when, I I ob.
F aka at a very great diftance towards ‘Achtermanashohe,
a human figure of a monftrous fize. A violent guft of wind
wing almolt carried away my hat, I clapped my hand to-it
by

234 _ Objervations on a fingular Phenomenon. ;

by moving my arm towards my head, and the coloffal figure . —

did the fame.

‘‘ The pleafure which I felt on this difcovery can hardly be
defcribed ; for I had already walked many a weary ftep in
the hopes of feeing this fhadowy image, without being able
to gratify my curiofity. I immediately made another move-
ment by bending my body, and the coloffal figure before me
repeated it. Iwas defirous of doing the fame thing once
more—but my coloffus had vanifhed. I remained in the
fame pofition, waiting to fee whether it would return, and
in a few minutes it again made its appearance on the
Achtermannshdhe. I paid my refpeéts to it a fecond time,
and it did the fame to me. 1 then called the landlord of the
Broken; and having both taken the fame pofition which I had
taken alone, we looked towards the Achtermannshéhe, but
faw nothing. We had not, however, ftood long, when. two
fuch coloffal figures were formed over the above eminence,
which repeated our compliments by bending their bodies-as
we did; after which they vanifhed. We retained our
pofition; kept our eyes fixed on the fame fpot, and ina
little the two figures again ftood before us, and were joined
by a third. Every moyement that we made by bending our
bodies thefe figures imitated—but with this difference, that
the phenomenon was fometimes weak and faint, fometimes
ftrong and weil defined. Having thus had an opportunity
of difcovering the whole fecret of this phenomenon, I can
give the following information to fuch of my readers as may
be defirous of feeing it themfelves. When the rifing fun,
and according to analogy the cafe will be the fame at the
fetting fun, throws his rays over the Broken upon the body
of a ‘man ftanding oppofite to fine light clouds floating
around or hovering paft him, he needs only fix his eyes
ftedfaftly upon them, ‘and, in all probability, he will fee the
fingular fpectacle of his own fhadow extending to the length
of five or fix hundred feet, at the diftance of about two

miles

Mr. Park’s Fourney into Africa. 235

miles before him. This is one of the moft agreeable phe-
nomena I ever had an opportunity of remarking on the
great obfervatory of Germany.” ,

{II. Ax Account of Mr. Parx’s Fourney into the Interior
Parts of Africa. From the Proceedings of the African
Affociation, 1798.

[Concluded from Page 204.1]

Tu E city of Sego, at which Mr. Park had now arrived,
confifted of four divifions or quarters, two on each fide of
the water; and each of them being furrounded by a mud
wall, it had the appearance of four diftin@: towns. The
houfes are built of clay, and have flat roofs; but fome of
them have two ftories, and many are white-wafhed. Be-
fides thefe buildings, Moorifh mofques are feen in every
quarter. Thefe objets, with the numerous boats on the
river, a crowded population, and the cultivated ftate of the
furrounding country, formed altogether a profpe& of civi-
lifation and magnificence which our traveller little expected
to find in the bofom of Africa. From the beft inquiries he
could make, he had reafon to believe that the place contained
altogether about 30,000 inhabitants.

The boats on the Niger are formed of the trunks of two

large trees rendered concave, and joined together, not fide
by fide, but lengthways, the junétion being exactly acrofs
the middle of the boat. They are therefore very long, and
difproportionably narrow ; and have neither decks nor mafts:
they are however roomy. ’ Mr. Park obferved in one of them
four horfes and a great many people croffing at a ferry.
’ To this ferry Mr. Park proceeded, intending to crofs
over to the largeft quarter of the city, where he was in-
formed the king of Bambara held his*refidence; but the
number of people prefling for a paflage was fuch as to pre-
yent his embarkation.

5

The

236 Mr. Park's fourney into Africa.

The multitude gazed on the ftranger with filent wonder 5
and he diftinguifhed with concern many Moors among them,
In the mean time, information that a white man was waiting
for a paflage was conveyed to the king; who immediately
fent a meflenger to inquire what brought-him to Sego, and
what he wanted? Our traveller; having given the beft an-
{wer he could as to the motives of his journey, added, that
he was there in his way to Jenne, and, having been robbed
of all he pofleffed, implored the king’s bounty and protecs
tion. The meffenger told him to go toa diftant village,
which he pointed out, and wait for the king’s farther orders.

Mr. Park complied with thefe direGtions, but found that
the inhabitants of the village were either averfe or afraid to
give him lodging or entertainment; and having turned his
horfe loofe, he fought fhelter from a ftorm of thunder and

rain under a tree. At length, as night approached, the kind-

nefs and humanity inherent in the female fex, to which he
had often been indebted on former occafions, came to his
relief on the prefent. A poor negro woman returning from
the labours of the field obferved that he was wet, weary
and dejected, and, taking up his faddle and bridle, told him
to follow her. She led him to her cottage, lighted up a
Jamp, procured him an excellent fupper of fifth, and plenty
of corn for. his horfe; after which, fhe f{pread a mat upon
the floor, and faid he might remain there for the night.
For this well-timed bounty our traveller prefented her with
two of the four brafs buttons which remained on his waift-
coat. Mr. Park relates that this good woman, having per-
formed the rites of hofpitality herfelf, called in the female
part of her family, and made them fpin cotton for a great
part of the night. They lightened their labour by fongs :
one of which muft have been compofed extempore; for our
traveller was himfelf the fubjeét of it ; and the air was, in
his opinion, the fweeteft and moft plaintive he had ever
heard. The words, as may be expected, were fimple, and
may be literally tranflated as follows : “ The winds roared,

and

—

et ae he ae

Mr. Park's Journey into Africa. 237
and the rain fell. The poor white man, faint and weary,
came and fat under our tree. He has no mother to bring
him milk—no wife to grind his corn.” ——Chorus. * Let
Us pity the white man; no mother hashe, &c. &c.”

Mr. Park contiriued all the next day in the village, with-
out receiving any orders from the king, and found himfelf
the object of univerfal inquiry. He foon heard enough,
however, to convince him, that the Moors and Slatees or
flave traders, refiding in Sego, were exceedingly fufpicious
concerning the motives of his journey, and in the higheft

degree hoftile towards him. He learnt that many confulta-
tions had been held with the king concerning his reception
and difpofal; and the villagers openly told him that he had
many enemies, and mufl expec no favour. ;
On the third day the meffenger arrived ; and, bringing a

bag in his hands, fignified to our traveller that he muft de-
part forthwith from the vicinage of Sego; but that Manfong
the king, wifhing to relieve a white man in diftrefs, had
fent him s0co kowries* to enable him to purchafe provi=
fions in the courfe of his journey. The meffenger added, .
that if Park’s intentions were really to proceed to Jenné, he
had orders to accompany him as a guide to Sanfanding.
Being thus compelled to leave Sego, Mr. Park applied
himfelf to collect all the information-he could from his
guide. ‘Though it was evident that this man was fent prins
cipally in the view of difcovering the motives and obje& of
his journey, he was found to be very friendly and commu-
nicative. By him Mr. Park was frankly told, that if Jenné
was the place of his deftination, he had undertaken an ene
terprife of greater danger than probably he was apprifed
of ; for, although the town of Jenné was nominally a part
of the king of Bambara’s dominions, it was in fa@ a city of

* Kowries.or cowries are finall fhells which in Africa and many parts
_ @f the Eaft Indies pafs current as money. In Bambaraa hundred of

them would purchafé a day’s provifion for a traveller, and corn for his
horfe, »

: | yas ae

238 Mr. Park’s Journey into Africas

the Moors; the principal part of the inhabitants being Bufha
reens or Mahometans;. and even the governor himfelf,
though appointed by Manfong, was of the fante fe&. Mr.
Park’s reflections on this occafion were aggravated by the
citcumftance, that his danger was likely to increafe as he ad-
vanced on his journey ; for he learnt that the places beyond
Jenné were under the Moorifh influence, in a ftill greater’
degree than Jenné itfelf ; and that Tombuctoo, the great
object of his refearch, was altogether in the poffeflion of
that favage and mercilefs people. _

Notwithftanding thefe difcouraging refleCtions, Mr. Park
perfifted in what he conceived to be his duty ; and the firft
town of note at which he arrived after leaving Sego, was
called Kabba. It is fituated in the midft of a beautiful and
highly cultivated country, “* bearing,” fays Mr. Park, “a
greater refemblance to the centre of England, than to what
I fhould have fuppofed had been in the middle of Africa ;”
and the feafon was that of the /oea harveft, or the gathering
in the fruit which produces the /hea-toulow or itree-butter,
the great abundance of which in this quarter was aftonifh-
ing. The tree itfelf very much refembles the American
oak ; and the nut, from the kernel of which the butter is
prepared by boiling it in water, has fomewhat the appear-
ance of a Spanifh olive. The kernel is enveloped in a fweet
pulp under a'thin green rind; and it is Mr. Park’s opinion,
that the butter produced from it, befides the advantage of
its keeping without falt the whole year, is whiter, firmer,
and of a richer flavour than the beft butter he ever tafted
made from cow’s milk. The growth and preparation of
this commodity feem to be among the firft objeéts of African
induftry in this and the neighbouring ftates ; and it confti-
tutes a main article of their inland commerce.

On the afternoon of the fecond day Mr. Park and his
guide reached Sanfanding, a very large town fituated on the

banks of the Niger, much reforted to by the Moors, who

bring thither large quantities of falt, which they barter for
7

foea

7
.

Ma. Park's Fourney into Africa. 239
rea toulou and gold duft. Leaving this place early next
morning, he proceeded to a town called Nyara, and from
- thence to Modibao, a delightful place on the banks of the
river, which is here very broad, and enlivened with many
{mall and verdant iflands, all of them ftocked with cattle
‘and crowded with villages. Here he was compelled to fet
off again abruptly, for fear of the Moors, the dosty or chief
man giving him a guide to Kea; but his horfe, which had
been long reduced to a mere fkeleton, dropped on the road,
and he was obliged to quit him. At Kea he embarked in a
fifhing canoe, and was landed in fix hours at Silla, a large
town on the fouthern fide of the Niger. At this place the
dooty was nearly as favage as the Moors, and it was with
great difliculty our traveller could get fhelter for the night.
He was now convinced by painful experience, that the ob-
ftacles to his farther progrefs were infurmountable, and that
in attempting to reach Jenné, unlefs under the protection of
fome men of weight and influence among the Moors, which
he had no pofhble means of obtaining, he fhould facrifice
himfelf to no purpofe; for his difcoveries would perifh with
him. He confidered at the fame time, that by returning to
Gambia in a different route, he might ftill promote in fome
degree the purpofe of his miffion ; for, having difcovered the
Niger at a great diftance from itshead, he fhould be adding
confiderably to the geography of Africa, in tracing this myf-
terious river up the ftream to its fource. On thefe and fimilar
confiderations Mr. Park determined to return to Sego, and,
proceeding from thence along the banks of the river, truft
for his fupport to the hofpitality of the negroes in the fouth-
ern {tates, out of the reach of Moorifh fanaticifm and malice.

The town of Silla, from which Mr. Park began his return
homewards, is within two fhort days journey of Jenné,
which is fituated on an ifland in the river. At the diftance
of two days more the river empties itfelf into a confiderable
lake, called Dibbie or the Dark Lake ; concerning the extent

aoe

240 Mr. Park's. Journey into Africa. .
of which, all the information which could be obtained was;

that in crofling over it from weft to ealt the canoes lofe
fight of land one whole day. From this lake the water iffues

in many ftreams, which terminate in two large branches.
One of thefe flows towards the north-eaft, and the other to

the eaft ; but they join again at Kabra, one.day’s journey > f

to the fouthward of Tombutoo, and the port or fhipping-
place of that city. The tract of land which the two ftreams _

encircle is called Jinbala, and is inhabited by negroes; and
the whole diftance by land from Jenné to Tombuétoo is |
twelve days journey. From Kabra, at the diftance of ele-
ven days. journey down the ftream, the river pafles to the
fouthward of Houffla, which is two days journey diftant
from the river. Of the further progrefs of this great river,
and its final exit, whether it be the fame that pafles by. Kaf-
fina*, or whether, as ancient charts feem to indicate, it
{preads into one or more inland lakes, or at an immenfe
diftance intermixes with the waters of the Nile, are. quef-
tions which future difcovery can alone refolve,

On the third day of Auguft Mr. Park deft Silla, Sater
ing to return through Sego in his way back to Gambia ;
and at Modibao he had the good fortune to recover his
horfe, whiclr he found fomewhat improved in condition.
Here he learnt that Manfong, having been perfuaded by the
Moors that our traveller had come into his country with
forft'mifchievous intention, had given orders to apprehend
‘him. Ue therefore thought it prudent to avoid Sego alto-
gether; which he accordingly did, by taking a circuitous
route until he had got confiderably to the weft ; when turn-
ing towards the Niger, he paffed through many towns and
villages on its banks; the largeft of which, called Sammee,
he left on the 14th of Auguft, and lodged that night at
Benni. On the morning of the 16th he arrived at Jabbee,
a large town with a Moorith mofque in it. The fame day

# Erroneoufly {pelt Cana.
: he

Mr. Park’s Fourney into Africa: "240

he pafled through Yamina, and on the 20th reached Kooli-

korro, a great falt-market: On the following day he pro-!
ceeded to Marraboo, and in two days more arrived at Bam-

makoo, the frontier of the kingdom of Bambara.

During the courfe of this peregrination through the king
of Bambara’s dominions, our traveller had to encounter the
tropical rains in all their violence ; and he was principally
indebted for his daily fupport to the dooty or chief man in
the feveral towns through which he pafled. This officer
feems to poflefs in fome refpects the authority’ of mayor in
the corporate towns of England ; and it refleéts great ho-
nour on the police of the African kingdoms, or on the be-
nevolent manners of the natives, that it is confidered one
part of the dooty’s obligation to provide food for the necef-»
fitous traveller :—To Suffer the king’s franger to depart buna
gry, {uch is the phrafe ufed, is an offence of a very heinous
nature. On many occafions Mr. Park offered payment, for
what he received, out of the kowries that ftill remained of
the king’s prefent, and his offer was fometimes accepted,
and fometimes refufed. On others he remunerated his hoft
in a fingular manner, the particulars of which deferve to be»
recited. Among the various impoftures pra@tifed by the
Moors towards the poor negroes, they frequently fell them
{craps of paper with an Arabic infcription (commonly a paf-
fage from the Koran), which are called Jephies or charms.
With one of thefe about his perfon, the pofféffr confiders ~
himfelf invulnerable, and neither the lurking ferpent nor
the prowling leopard is any longer the object of his dread.

Tn the circumftances to which Mr. Park was reduced, he had

the good fortune to difcover that the negro natives afcribed

to him the power of granting faphies of even more than

Arabian virtue. If a Moor’s faphie is good,” faid the
dooty of Sanfanding, “a white man’s muft be better;” and
Mr. Park, at his requeft, gave him one pofleffed of \all the
virtues he could concentrate, for it contained the Lord’s
Prayer. The pen with which it was written was made of a

; Var. I. : R Ge: reed 5

242 Mr. Park's Fourney into Africa.

reed; a little charcoal and gum-water made very tolerable
ink, and a thin board anfwered the purpofe of paper. In
his journey weftward this merchandize turned to extraordi-
nary good account; and it is furely needlefs for Mr. Park
to frame any apology for having availed himfelf of fuch a
refource in his fituation.

At Bammakoo the Niger ceafes to be navigable. It takes
its rife at a {mall village called Sankari in the high lands of
Jallonkondoo, about fix days journey S. W. from Bamma-
koo; and the country becoming mountainous, our traveller
on the 22d took the path for Sibidooloo, where he arrived
at the end of two days. On the 30th he came to Wonda, a
fine village regularly built and furrounded by a wall. Here
he was confined feveral days by ficknefs; and having no-—
thing elfe to offer to the friendly negro, in whofe houfe he
was accommodated, Mr.Park prefented him, at parting, with
his horfe, now indeed become unable to proceed any farther.
On the 8th of September he fet out on foot for Kinneyeto,
a confiderable town, which he reached on the 11th, and in.
three days more arrived at Kamalia. At this place ‘Mr.
Park, worn down by fatigue and the viciflitudes of the wea-
ther, having fometimes been plunged up to the neck in ri-
vers and {wamps, and fometimes loft in woods and deferts,.
without fhelter, clothing, or food, fell into a fevere and dan-
gerous fit of ficknefs, in which the remembrance of paft fuf-
ferimg, and the hopes of future enjoyment, had nearly been
extinguifhed together. On his arrival at Kamalia he had
ftill a {pace of 500 miles to traverfe before he could reach
any friendly country on the Gambia; and being informed:
that great part of the way lay through a defert, which it
was impoffible he could crofs fingly and unfupported, he
had no other refource but to wait for the firft caravan of
flaves that might travel the fame track. Such a one was
expected to pafs through Kamalia at the end of three months,
and the chief direCtor of it refided in that place. To him,
therefore, Mr. Park applied ; and for the value of one flaye,

. te

Mr, Park's Fourhey into Africa. : 242

to be paid on his fafe arrival at the Gambia, this worthy
negro, whofe. name was Karfa Taura, not only undertook
to condu& him fafe to Pifania, but offered him likewife the
-accommodation of his houfe until the time of the caravan’s’
departure. Under this man’s roof our traveller was con- .
fined to a maf, which was his only bed, by a fevere and dan-
gerous fever for upwards of a month. Five months longer
he was detained for the caravan. During this long interval
not a murmur efcaped the lips of Karfa, or of any of his
wives, at the trouble and expence which their inmate brought
upon them. ‘To the kind attentions, the tender folicitude,
the cheerful affiduity, and warm hofpitality of thefe poor
Pagans, Mr. Park declares he is indebted not only for his
fafe return to Great Britain, but alfo for the prefervation
of his life; and he admits that he made his friend Karfa but
an inadequate return, though the beft in his power, by pre-
fenting him, on their arrival at Gambia, with double the fum
that he had originally promifed.

The whole of Mr. Park’s route, both in going and re-
turning, having been confined to a traét of country bounded
nearly by the 12th and 15th parallels of latitude, it muft be
imagined that he found the climate in ail places exceedingly
hot. On the borders of the defert, where the fiercenefs of
the tropical fun is refle&ed from the fands, the heat was
Acarcely fupportable. Having been robbed of his thermo-
meter, he had no means of forming a comparative judg=
ment; but he well remembers that in the dry feafon, when
the wind blows from the eaft and north-eaft acrofs the de-
fert, the ground became fo hot in the middle of the day as
not to be borne by the naked foot. In the camp at Benowm
even the negro flaves, accuftomed as they were to this tem-
perature, could not walk from one tent to another without
their fandals. At this time of the day the Moors lie ftretched
at length in their tents, either afleep or unwilling to MOve 5
and Mr. Park declares, that, as he lay liftlefsly along after
their manner in his hut of reeds, he could not hold his hand

h R2 againft

2A . Mr. Park's Fourney into Africa.

againft the current of air which came through the crevices,
without fuffering very fenfible pain from its feorching effect.
In the fouthern diftricts, which abound with wood and wa-
ter, the climate improves; and in the mornings aud even-
ings the air is ferene, temperate and pleafant. During the
rainy feafon the prevailing wind is from the fouth-weft.
The monfoon commonly changes about the latter end of
June, and the wind continues to blow from the fouth-weft
quarter until the middle or end of October. In this inter-
val the country is flooded, and the rains are preceded and
followed by dreadful tornadoes or typhons. The com-
mencement of this monfoon is the {pring or feed-time, and
its termination is commonly the feafon of harveft.

Among the principal productions of the negroe territories
is the /otus. It is rather a thorny fhrub than a tree, and
abounds in all the countries which Mr. Park traverfed ; but
it thrives beft in a fandy foil. Its fruit is a {mall yellow fa-
‘rinaceous berry, about the fize of an olive, which being
pounded in a wooden veffel, and afterwards dried in the fun,
is made into excellent cakes refembling in colour and fla-
‘your the fweeteft gingerbread. Some of the natives pre-
pare from it alfo a liquor delicioufly fweet.

Of one fpecies of their corn the negroes make excellent
beer, by malting the feeds nearly in the fame manner as
barley is malted in England; and the beer which is thus
made was to Mr. Park’s tafte equal to the beft ftrong beer
he had ever drank in his native country.

In the latter end of April 1797 the coffe or caravan being
at length completed, and our traveller’s health re-eftablifhed,
he fet out from Kamalia in company with feventy perfons,
of whom only thirty-feven were flaves for fale. In nine days
they came to Maana, bordering on a branch of the Senegal.
In ten days more they reached the fmall but fertile ftate of
Dentilla, and crofled in their journey fome of the ftreams
that contribute to the great river of Gambia. On the 4th
of June they fell in with that river, about two days journey

above

s

ss 7
ue ¢. .

French Weights and Meafures. 245

above the falls of Baraconda, to which place it ‘is navigable —
for canoes from its mouth; and in fix days more, on the
1oth of June, Mr. Park, to his infinite fatisfation, having
undergone in his journey, from the heat of the weather,
from fatigue, and from hunger, more than he could find
words to defcribe, entered the hofpitable manfion of Dr.
Laidley, from which he had fet out eighteen months before.

On the 15th of the fame month he embarked in a flave
fhip bound to America; which being driven by ftrefs of
weather to Antigua, Mr. Park took his pafflage from thence
in a veffel bound to Great Britain ;- and on the 25th of De-
cember laft arrived fafely in London,

IV. Explanation of the French Meafures and Weights, pointing

out their Value and principal Ufes, according to the Law of

Germinal 18th, 3d Year of the Republic. From the Journal
de Phyfique, 1798. |

MEASURES OF LENGTH.

CENTIMETR E. The hundreth part of the metre.
This is rather a fubdivifion than a particular meafure *.

Decimetre. Tenth part of the metre. The double deci-
metre makes a very convenient meafure for the pocket.

Metre. The ftandard of the meafures of the republic
being the ten-millionth part of a quarter of the meridian, or
the length of about 3 feet 114% lines; it may ferve for
meafuring cloth, fluffs, &c.. It makes about the ordinary
height of a walking-ftick, which any perfon may carry in the
hand. ‘The demi-metre and the double metre may be ufeful
for different kinds of meafurement.

Decametre. Yen times the length of the metre. About
thirty feet ten inches. Proper to form a chain for land-
furveying.

* The millimetre, or the thoufandth part of the metre, might be here

mentioned ; but it is of little ufe in commerce.

R 3 Hefometre, -

246 | French Weights and Meafures,

Heétometre. Length of a hundred metres. ‘Will not be
ufed.

Kilometre. Equal to a thoufand metres, or about 580
toifes. Four will make about a common league.

Myriametre. Its value is ten thoufand metres, or about
58co toifes, which is a little more than one Stage. The
kilometre and the myriametre will be convenient to exprefs
diftances in itineraries, and to regulate boundaries in order
to meafure the highways.

MEASURES OF CAPACITY,

Centilitre. There is no need for a fmaller meafure of this
kind. . It may be confidered as equal to a fmall glafs for
fpirits and liquors. The double of it would ferve extremely
well for the fame purpofe.

Decilitre. This is almoft equivalent to a common goblet.
The ufe of it may be readily conceived. Its half and its
double are analogous to other meafures now employed for
liquids. » ;

Litre. Its content is equal to a cubic decimetre. It
_ differs very little from the /itron, and the Paris pint; and
may be employed in the fame manner, either for liquids or
dry fubftances. Its half and its double will be alfo very
ufeful.

Decalitre. Xt may be fubftituted, as well as the double:
decalitre, for meafuring corn and all forts of grain. .

The demi-decalitre may fupply the place of the picotin
(peck). ) )

HeGolitre will ferve for various dry fubftances, fuch as
grain, falt, plafter, lime, coals, &c. The content of this
meafure might be given to cafks for wine. The demi-
heGolitre will be alfo exceedingly ufeful, and particularly for
grain. net
Kilolitre. Equal in content to a cubic metre.. It is
equivalent almoft to the ton ufed in fhipping, which is

not

French Weights and Meafures. 247

not fo much an inftrument of meafurement as a mode of
valuation.
The myrialitre is fuperfluous *.

WEIGHTS:

The millizramme would weigh a little lefs than = of a
grain, confequently would give much more exaétnefs than
the 32ds which have been ufed hitherto ; but as this meafure
is employed only in very nice operations, which do not occur
in the common ufages of commerce, weights may be con-
fined to the following :

Centigramme. The hundredth part of a gramme, or
about + of a grain.

Decigremme weighs a little lefs than two grains. The
demi-decigramme is almoft equal then to the common grain.

Gramme. Equivalent to the weight of a cubic centi-
- metreof water, which makes about nineteen grains. Very
analogous to the gramma of the Greeks, from which it takes
its name. It is exceedingly proper to ferve as unity in
weighing valuable articles, fuch as gold and filver, and all
thofe which require a great deal of accuracy. 4

Decagramme. The weight of ten grammes. Its half
makes about a gros (adram) and a third. Its double isa
jittle lefs than two thirds of an ounce.

Heétogramme. ‘The weight of a hundred grammes.

Kilogramme. The weight of a thoufand grammes, very
convenient to be ufed in the fale of the moft common articles.
Its half exceeds our ufual pound by about three gres.

Myriagramme. The weight of ten thoufand grammes, a
little lefs than 203 pounds. Its double will form the largeft

* If the feries of decimal litres increafed by the doubles and halves of
each be compared with the ancient meafures, it will be feen that, from the
centilitre to the decaliire, they agree perfeétly for liquids; and from the
demilitre to the heéfolitre, for the various dry articles.

R 4 weight

248 French Weights and Meafures.

weight neceffary to be employed, and will anfwer with great
advantage for that purpofe *. . ty

-
!

AGRARIAN MEASURES.

Centiare. Deciare. The centiare and deciare are only fube ~
divifions of the are. The firft is equal to a fquare metre.
The fecond is equal to ten.

Ane. The unity of meafures for land or furveying. It
is equivalent to a {quare decametre, or a hundred fquare
metres (about 25 fquare toifes). It is well fuited for the
meafurement of the valuable ground in cities, gardens, and
{mall poffeffions, or fuch as are of a moderate extent. The
denomination of deca-are, or decare by fhortening it, will
f{carcely be of any ufe.

Heélare. ‘This isa fuperficies containing a hundred ares.
It may be employed for meafuring lands of a certain extent.
‘The he@are is fomewhat lefs than double the large acre of
100 fquare perches, the perch being 22 feet.

The i/are is of no importance. —

Myriare. Equal to ten thoufand ares, or a fquare the
fide of which ts a kilometre. Ic is confequently proper for
the meafurement of lands of little value, fuch as commons,
&c. when it is not neceflary to exprefs them in fquares of
jong meature.

MEASURES FOR FIRE WOOD.

Stere. A quantity equal to a cubic metre. By giving
the length of a metre to billets, nothing more will be necef-
fary, in order to obtain the ftere, than to range them within

* The utility of the doubles and halves of each of the weights, which
compofe the decimal feries, may be readily conceived. By forming of the
whole one feries, it will be feen that it is extremely analogous to that of
the ancient weights, for which it'may be fubftituted with great advantage

in n ali commercial tranfactions.

a {quare

a

French Weights and Meafures. 249

a {quare frame (cha/fis), each fide of which is equal to a metre.
If the billets have another‘length, for example 3+ feet, as re=
quired by the ordinance refpeQiing waters and foretts, a {mall
change only will be required in the height of the frame; and
this will be attended with no difficulty.

The ftere will be very convenient. It will be about half
the demi-voie * of wood at Paris.

The demi-/tere and the double ftere may alfo. be employed.
Laftly, the deci-ffere, or rather the double deci-fere, may be
ufed likewife to regulate the fize of faggots, and the meafure
of fmaller pieces of wood (cottrels), by determining their pro-
per length.

‘The other.combinations of the ftere do not feem to prefent
any utility of confequence.

MONEY.

The different divifions of money are confidered here as
imaginary coins, without paying any regard to the proper
value of the principal unity.

Centime. he hundredth part, or value of the hundredth
part of a franc.

Decime. Tenth of a franc, equal to two fous.

Franc. Principal unity of the French money, or the
fame as the livre of 20 fous. Its abfolute value, that is to
fay, the quantity which it will purchafe of a certain fort of
merchandife, varies, as is well known, according to circum-
ftances,

* A vole is equal to half a cord, the cord being eight feet in length
and four in height. The demi-voie then is equal to a quarter of a
cord, Epir.

.

\

V. Account

Cage iy

W. Account of Dr: PERKINS’ sDifcovery of the Influence ef Me
tallic Traéfors, in removing many of the Difeafes of the Human
Body.

‘Tass difcovery has made fome noife in America, and,
like every novelty, has its advocates and its opponents. The
fon of the inventor, now in London, has publifhed a {mall
work on the fubject, to introduce it to the notice of medical
men in this country, from which we extract the following
particulars,: .

Galvani, the celebrated profeffor at Bologna, was the
firt who announced fome curious phenomena, obferved
from an accidental application of metallic fubftances to the
nerves and mufcles of animals. The fubje€t immediately
engaged the attention of philofophers throughout Europe,
and the public, in confequence, were foon favoured with a
confirmation of Galvani’s aflertions, by the publication of
the experiments. of Valli, Volta, Fowler, Monro, Cavallo,
&c. The tefult of thefe various refearches proved that
‘the influence is not peculiar to a few animals only, but
feems to be a property of all.” Although the living animal
is moft fufceptible of the influence, yet, from a combination
of different metals, the nerves and mufcular fibres, long
after every appearance of vitality was removed, have been
excited to powerful aCion.

From the difcovery of a new law *, acting fo important a
part in the animal cceonomy, it might rationally be expected
that attempts would be made to afcertain how far this prin-
ciple could be applied in a remedial point of view:to human
difeafes. ‘This has been the particular enquiry of Doétor
Perkins.

* The term ANIMAL ELECTRicITY, which arofe from the many anae -
logies that were obferved between the influence difcovered by Galvani
and electricity, has by later writers given place to GALY ANISM, a com-
pliment well merited by the ingenious difcoverer.

Several

Influence of Metallic Traitors. 25%

Several phenomena relating to the influence of metals in
cafes of pains, he had obferved before the news of Galvani'’s
difcovery had reached America 5 and when the phyfiologifts
of | urope were engaged in experimenting on the denuded
nerves and mufcles of the fmaller animals, with a view to
afcertain. the agency of this incomprehenfible property in
them, Dr, Perkins was profecuting a feries of experiments,
which confitied in applying externally, to parts affeéted with
difeafe, metals and compounds of metals, of every defcrip-
tion, which octurred to him, and conftru@ted into various
forms and fizes. The refult proved, that on drawing
lightly over the parts affected certain inftruments, termed
+;ractors, which he formed from metallic fubftances into
pointed fhapes, he could remove moft of thofe topical dif-
eafes of the human body, where an extra degree of nerv-
ous energy or vital heat was prefent ; unlefs fuch difeafe
was fituated in fome of the internal vifcera, too remote from
the part where the inftruments could be applied. The dif-
eafes which have been found moft fufceptible of the influ-
ence of the tractors, are rheumatifm, fome gouty affeCtions,
pleurify, 0, hthalmias, eryfipelas, violent fpafmodic convul-
fions, as epileptic fits and the locked jaw, the pain and {welling
attending contufions, inflammatory tumors, the pains from
a-recent fprain, the painful effects of a burn or fcald, pains
in the head, teeth, and indeed moft kinds of painful topical

-affe€tions, excepting where the organic ftructure of the part
is deflroyed, as in wounds, ulcers, &c. and. excepting alfo
where oils or fome other non-conduéting fubftances are
prefent.

This pradtice, like all confiderable innovations, on its fir ft
introduction, encduntered the fevereft fcepticifm and ridi-
cule, and a medical fociety pronounced it a revival of the
exploded practice of animal magnetifm ; but the’prefident ~
and many of the members of that fociety afterwards applied
the traétors to practice, and have fince publifhed the fuccefs
of their numerous experiments.

As

252 Influence of Metallic Traétors.

’ As moft phenomena are learned from obfervation long be-
fore we arrive at the theory which conneéts and explains
them, fo with this metallic influence, no clear and fatisfac-
tory explanatiort of the modus operandi has yet appeared.

Notwithftanding the affiduity with which phyfiologifts
have purfued their enquiry, and are ftill purfuing*, to dif-
cover the laws and properties of Galvanifm, and to afcertain
the extent of its action in the animal ceconomy; yet, like
many other phenomena, they ftill remain myfteries.

Mr. Meigs, profeflor of natural philofophyat Newhaven, in
a letter on Dr. Perkins’s difcovery, conceives the principles of
metallic irritability fo little underftood, that he will not pre-
tend to'explain 4ow the tractors produce their effeéts; but

fering fatisfied in finding that the effects are produced. After,

flating an experiment on his own child, eight years of age,
very dangeroufly ill with a peripneumonic complaint, and
to which the tra€tors gave almoft inftantaneous relief, he
faye, °° 1 have ufed the tra€tors with fuccefs in feverat
"other cafes in my own family; and although, like Naaman
the Syrian, I cannot tell why the waters of Jordan fhould
be better than Abana and Pharpar, rivers of Damafcus; yet,
fince experience has proved them fo, no reafoning can change
the opinion. Indeed, the caufes of all common faéts are,
ave think, perfectly well known to us; and it isvery probable,
fifty or an hundred years hence, we fhall as well know why

* The celebrated Von Humboldt of Germany has lately publifhed a
volume of sco pages 8vo, and is now preparing another. Thefe confift
of numerous experiments, chiefly on the nerves and mufcular fibre 3 and
’ {om the fuccefs with which his enquiries have already been attend-
ed, great hopes are entertained that fomething important will refult.
M. Creve, profeffor of medicine at Mentz, has lately publifhed an im-
portant traét on Metallic Irritability. He maintains, from a variety of
experiments made on the dead bodies of men and animals, thgt even the
fymptoms of putrefaGlion do not conftitute an infallible evidence of death,
but that the application of metals will in all cafes afcertain it beyond the
peiibility of miftake. This difcovery is of great importance, as it may be

applied te prevent the dreadiul error of premature inhumation,
the

ne

|

Influence of Metallic Tradhrs. 253
the metallic tractors fhould in a few minutes remove violent
pains, as we now know why cantharides and opium will
produce oppofite effects: viz. we fhall know but very Uttle

about either, excepting fads.”

Mr. Woodward, profefflor of natural philofophy at Dart-

mouth, in a letter alfo on the fame fubje&t, has ftated a

number of fuccefsful experiments in pains of the head, face,
teeth, and in one cafe of a fprain.

Dr. Vaughan, 2 member of the Philadelphia medical
fociety, has lately publifhed an ingenious traQ on Galvanifm,
the object of ‘which is to account for the influence of the
tractors in removing difeafes. After a citation of numerous
experiments made on the nerves. and mufcles of animals, he
obferves, ‘‘ If we only take an impartial view of the opera-
tions of nature herfelf, and attend diligently to the analytical
inveftigations of the aforementioned experimentalifts on this
fublime fubje€, I think the fceptic mutt admit that the prin-
ciple of nervous energy is a modification of ele€iricity. As
fenfation is dependent on this energy,a pleafurable fenfation,
or what may be termed a natural or healthy degree thereof
then certainly pain or fuperfenfation can only depend on
an accumulation of the eleétric fluid, or extra degree of
energy in the part affefted. On this principle the problem
admits of eafy folution; namely, that the metals, being fuf-
ceptible of this fluid, conduét the extra degree of energy to
parts where it is diminifhed, or out of the fy{tem altogether,
refloring the native law of electric equilibrium.”

Drs. Tilton, Baker, Hall, Lord, Brewfter, Dalho, Dyer,
Johnfon, Backus, Lee, Willard, Marvin and Gofs, of Ame-
rica, have publifhed their approbations of the ufe of metallic
tractors; which are in fact only pieces of pointed i iron of

brafs, &c. How far the attempt of the author to explain

their a€tion upon the principles of Galvanifm has been fuc-
cefsful, we will not take upon us to determine. We fhall
only obferve, that were it even demonftrated to be a revival
of animal magnctifm, if its efficacy be at the fame ‘ime de-

9 morjirated,

"

254 Influence of Metallic Traéors.

mon/firated, it will not be therefore rejected ; for in that cafe
it would only be-a proof that the empiricifm of the praétifers
of magnetifm, by introducing abfurd glare, fhow and myftery,
had been the means of obfcuring the principles on which it
was founded. We are led to make this remark by an ob-
fervation of the author, ‘* That in fome ‘inftances the
metallic influence, when excited by different perfons, produces
different effetis. Experiments made to afcertain the point,
proved that there were perfons who might ufe the tractors
for any length of time, in difeafes which were fuitable for
the operation, and produce no perceptible effect; when by pla-
cing them in the hands of another perfon, who fhould perform
the operation precifely in the fame manner as before, the
pain or inflammation would be removed direéily.” A note in-
troduced here by the author, to prove by this faét the
analogy between the influence of the tra€tors and Galvanifm,
does not appear, to us, to be in point. ‘‘ On the application
of zinc and filver to the tongue, the fenfation of tafte is very
flight to fome, while with others. it is very ftrong :—when
the experiment is applied to the fenfe of fight, fome are
hardly fenfible of it, while others obferve a trong flafh.”
Here, however, the caufe of the different effe&ts produced

~ muft be fought for in the modification, or peculiar ftru€ture,

of the organs of fenfation i the patiént—not in the operator.
We mean not by this obfervation to detract from the
merit of the difcovery: that muft reft, independent of all
theory, on the degree of evidence that may be brought
forward to fupport it.. If the facts fhall be fufficiently con-

‘clufive to eftablifh the efficacy of the tractors, in removing

‘only one /pecies of difeafe, the inventor has nothing to fear
from the oppofition of the faculty in England :—the gentle-

men who compofe that body are too liberal to oppofe any

beneficial innovation, merely becaufe it comes from a
foreigner. _On the other hand, if the cures reported to have
been performed in America cannot be effected here by the
fame means, and in cafes in which there can be no ambiguity,

they

ae

J
|

. nore
An Analyfis of tevo Mineral Springs, ee 2.55

they are too enlightened to be impofed upon, and induced

Si to give the practice a countenance and fupport to which it
may. have no claim.

i ~

}. VI. An Analyfisof the Waters of two Mineral Springs at

Lemington Priors, near Warwick ; including Experiments
"tending to elucidate the Origin of the Muriatic Acid. By
Wirtiam Lambe, M. A. late Fellow of St. Fobn’s College,

Cambridge. From the Memoirs of the Literary and Philo-

fophical Society of Manchefter, Vol. V. Part I.

Tue author of this ingenious paper has fhewn himfelf a
mafter in the art of analyfis. The apparent difcoyery of the _
* origin of the muriatic acid, to which Mr. Lambe’s labours
‘ have led, is fo well worthy of the attention of philofophers,
as it may lead to a difcovery of the compofition of other _
acids whofe bafes are at prefent unknown, that we have not
a doubt but the path he has laid open will be explored by
all the able chemifts of Europe. .

After fome very pertinent introdu€tory remarks, the_
author obferves, that as both the {prings rife many feet below
the earth, it feems needlefs to enter into any particulars
concerning the nature of the furface, or the qualities of the
foil of the circumjacent diftrict, and therefore proceeds to
i the objects of his enquiry as follows:

ON THE WATER OF THE NEW BATHS,

The {pring was difcovered in the year 1790, at the depth

\ of 42 feet from the furface of the ground. A well is funk
; about 24 feet deep. In the courfe of this depth there is a
rock the thicknefs of 8 or 10 feet; afterwards a. bed of
mari; after penetrating which, another rock, much harder
than the former, is found. Through this fecond rock a bore
is made 18 feet deep, where there is a fmall cleft in the
rock. There are many little fprings found in this coi rle;
a | but

256. An Analyfis of twe Mineral Springs.

but from this cleft the water rifes with violence to the level
of 4 feet above the furface of the ground ; and it affords a
conftant and copious fupply of frefh water.

I. ON THE GASEOUS FLUIDS. -7

The water, when frefh drawn, f{mells of fulphurated
hydrogen, or hepatic * gas; but it quickly becomes inodor-
ous by expofure to the atmofphere. I have obtained no
more than 4 cubic inches of gafeous fluid from a wine-
gallon of the water. Of thefe, hardly half a cubic inch is
abforbed by the water; and, 1. Nitric acid dropped into this
folution caufes a minute precipitate of fulphur; hence fome
hepatic gas has been expelled by the boiling. 2.1 put fome
of the water, which had not been boiled, into a bottle, leav-
ing a part of the hottle empty: I then filled the bottle en-
tirely with lime-water, and ftopped it. A white precipitate
fell, which, with the addition of diftilled vinegar, effervefced
fenfibly, but not ftrongly. The half cubic inch is, therefore,
moftly carbonic acid. 3. Into the portion of the air which
was not abforbed by water, I plunged a lighted candle; it
was initantly extinguifhed. ‘This portion is, therefore,
azotic gas.

Il. THE SPONTANEOUS PRECIPITATE.

A fediment falls to the bottom, and adheres to the fides
of the bath. It is of a yellow colour, and acquires additional
brightnefs by expofure to the atmofphere. A fimilar fedi-
ment may be feparated by boiling the frefh water. Froma
gallon of water, .75 of a grain is procured. This diffolves
readily in acids, and fhews all the common and well known
appearances of oxydofiron. It muft have been united with
the carbonic acid, which has been already detected. (1, 2.)

* T mnft take leave to retain this name in the following pages, pre~
ferring it (if for no better reafon, at leaft for its fhortnefs) to the coms
pound term.

III. SOME.

at Lemiagton Priors. 257

tit. soME ANOMALOUS SPPEARANCES WITH PRECIPITANTS.

~

1. After the fpontaneous precipitate has been feparated,
a little oxygenated muriate of mercury was diflolved in a
glafs full of the water. A white matter feparated during
the folution, and, in fome hours, colleéted in confiderable
“quantity.

2.-A piece of faipbare of argill was dropped into a jar of
the fame water; prefently a ftratum of white matter was
formed at the bottom of the jar : but this appearance is tran-
fitory ; for in the courfe of an hour or two the precipitate is
re-diffolved, and the water refumes its tranfparency. This
i$ an‘appearance which I had not found noticed by writers
on the fubject, though I have reafon to think it not uncom-
mon. ‘The waters of Aftrop, near Banbury, contain car-
bonat of lime diffolved by the carbonic acid: and, when
“the carbonat has been feparated, by boiling the water, the
fame appearance is produced by fulphate of argill. Its
origin; and that of the decompofition of the mercurial falt,
will be fhewn in the fequel.

IV. THE METALLIC SALTS.

Several phenomena demonftrate the exiftence of fome
metallic fubflance in this water, befides the precipitate
already defcribed (11.): but it is fo peculiarly combined, or
otherwife modified, as to clude, in a great meafure, the
action of the ordinary re-agents. When the water is boiled
in contact with fome of the metals, it becomes turbid; and
the metal is partly oxydated, and partly diffolved. The iron,
which has been ufed in the conftrudiion of the baths, is:
almoft deftroyed: the tin, which lined a veffel ufed as a
warm bath for children, has fuffered in like manner. If the
water be only boiled and poured into a wine-glafs with a
bright key in it, the liquor becomes turbid before it is cold.
Copper feems to refift its a€tion better; but this is only in
a low temperature ; for, if the water be boiled im a copper

Vou. I. S yelel,

258 An Analyfis of two Mineral Springs

proved by putting a bright piece of iron into the liquor,”
which, in a few hours, acquires 2 coppery coating *. Lead
alfo I have found to be acted upon.

I examined, with fome minutenefs, the precipitates formed
by iron and by copper. 2. The firft is of a yellow colour?
and; though it is not magnetic, it may be made fo by the
flame of a blow-pipe upon charcoal. It confifts, therefore,
of oxyde of iron, either totally or in part; but whether it is
derived from the liquor, or from the iron whieh was ufed to
procure it, cannot be determined by this experiment. But
the following obfervation demonftrates, that iron is contained
in the water itfelf. 3. The water was boiled in a copper
veffel, and the precipitate formed was colle&ed. This is
alfo of a yellow colour; and, expofed to the flame of a blow-
pipe on charcoal (like the former precipitate), it became
magnetic. It feems alfo to contain copper; for, precipitating
its folution in muriatic acid by ammoniac, the liquor became
blue; the colour however was by no means ftrong. _

When the falts of the water have been concentrated by
evaporation, copper is acted upon more powerfully; im fo
much that if a filver fpoon be ufed for.the evaporation it is
much tarnifhed, and the falts acquire a cupreous tafte and a
yellow tinge, though they are colourlefs if the evaporation
be made in glafs. Thefe veftige®of the copper muft be at-
tributed to the alloy of the fpoon.

The appearances f have defcribed furprifed me the more,
as, from the ufe of fome of the common re-agents, I had
formed oppofite conclufions. 4. Prufhiat of pot-afh, before
the water has been boiled, forms a green cloud, but in a

* This remark evinces the ftrong neceffity of a chemical examination ef
all the fubftahces ufed as medicines. It is very common to warm the
water with a view of quickening its laxative power. It is evident with
what caution veffels in which copper is an ingredient fhould be ufed for
this purpofe; or, rather, with what care they fhould be utterly avoided.

quantity —

at Lemington Priors. 259

uantity hardly fufficient to precipitate. After boiling there
is no decompofition); nor is there any if the liquor be eva-
porated to half its original bulk. 5. Tincture of galls ftrikes
2 purple colour before the water is boiled: after boiling
there is a precipitate likewife, but of. a dull lemon colour ;
after a partial evaporation, the colour approaches to white-
nefs. In each of the two laft cafes, the liquor gradually ac-
quires a deep yellow tinge. In thefe éxperiments, we have
none of the drdinary figns of iron, except the carbonat (11.),
though its exiftence in the water has been proved beyond
queftion (3). .

V. MANGANESE IS DISSOLVED IN THIS WATER.

As zinc is known to have a ftronger affinity to acids than
the other metals have, I hoped by its mean to obtain fome
information on the caufe of the facts I have defcribed. 1.1
boiled, therefore, fome of the water in a glazed veffel, in
contact with fome pieces of zink: a fmall, precipitate was
formed, but enough to be colle&ted for examination with
the blow-pipe. This was fufed with borax; and a globule
was formed of a rich red colour, precifely that communi-
cated by manganefe*. Continuing the fufion, the colour
vanifhed ; nor could I make it re-appear by the yellow
flame of the blaft: probably becaufe the manganefe was
fnixed with another metal. .The globule was removed to a
filver fpoon ; and, then, by fufion, it regained the red co
lour. To avoid the poflibility of error, a little manganefe,
fufed with borax in the fame manner, was placed befide the
red globule; and no difference could be obferved in the co-
flour of the two globules, except a flight variety in the in-
tenfity +. 2 The semon-coloured precipitate, formed by the

tincture

_ * For the properties of this mineral fee Scheele’s Effay on Manganefe ;
or Bergman on the White Ores of Iron.

+ Lam aware of the obfervation of Bergman, that zink does not preci«
pitate folutions of manganefe. Sec his Effays, vol- iii, p. 414s But, be-
: S2 fides

"260 An Analyfs of twe Mineral Springs -

tincture of galls (1v. 5.), yields the fame refult. By ufing’
a large quantity of the water, I colleéted fufficient for exa-
mination. This I put over a fire on an iron plate: the ve-
getable part took fire anti burnt away: the powder became
of an oehry yellow, and was magnetic :—fufed with borax
by the blow-pipe, it acquired the rednefs which manganefe
imparts.

3. The fame fat may be proved by a fingle experiment.
~ Jt is known that tartrite of pot-afh decompofes falts of man-
ganefe by a double affinity; in confequence of which; tar-
trite of manganefe, which is a fubftance infoluble in wa
ter, precipitates*. I poured, therefore, a folution of tar-
trite of pot-afh into water, and there fell a copious cryftalline
precipitate. Much iron fell down with the manganefe, as
might be expected’ from the affinity between the oxydes of
thefe metals: for, by fufing the precipitate with nitre, green
{pots were formed:on the fides of the erucible.

Tartrite-of pot-afh décompofes’ likewife falts of lime, as
is well known; but the tartrite of lime is precipitated in
the form of a white powder, which isnot fenfibly cryftalline.:
But as there is a great abundance of lie in this water
(x1v.), it feems probable that it had entered into: the com-:
pofition of thefe cryftals.

Manganele has been but rarely noticed as entering into’
the compofition of mineral waters. » The-reafon, perhaps, is,
that it has been feldom looked for, rather than that it feldom:
exifts ; fince it is now known to bea fubftance abundantly
diffufed through the earth. ‘The waters of Aftrop, which F
have mentioned above (111. 2.), decompofe tartrite of pot-
afh, and form a cryftalline precipitate when its carbonate of!
lime has been thrown down by boiling. ‘This water, im
thefe circumftances, hardly affects either tin&ture of galls or

fides that I deferibe only what I have feen, it will appear that the falt im

queftion is of fo peculiar a nature, that it cannot be reise to obey the

ufual analogies of the other folutions.
# See Sclicele as‘aboye.

oruffat

at Lemington Priors. ; 261
pruffiat -of pot-afh. Every chalybeat fpring may be fuf-
pected to contain fome manganefe likewife ; and fhould
‘therefore be examined accordingly.

VI. TESTS OF MANGANESE AND IRON.

As I fhall have frequent occafion to mention this mix-
aure of oxydes of manganefe and iron, I will enumerate the
tefts I have ufed, to avoid ufelefs repetitions. Thefe are, 1.
The magnet: to this the fmalleft particle of iron may be
rendered obedient, by expofing it to a due heat, on char-
coal, by the blow-pipe. 2. Ihe tinge communicated by
the procefs to a globule of borax: this from iron is green or
yellow; from manganefe it is hyacinthine; or, when the
globule is more loaded with the metal, a fine rich red. This
colour difappears by the blue conical flame; and may be
ze-produced by the gentler yellow flame which furrounds
thecone. 3. Fufion with nitre, or with carbonate of foda:
manganefe imparts to them a fine blue colour; but if it be
mixed with the oxyde of iron the colour is green.

YU. AN HYPOTHESIS To EXPLAIN THE CAUSE OF THE
PHENOMENA.

The firft hypothelis which I framed, to account for the
facts in queftion, was deduced from the well-known pro-
perty which manganefe poffeffes of oxygenating the muriatic
acid. My reafoning was as follows :—Since, during the
folution of the black oxyde of manganefe in the muriatic
acid, a portion of the acid becomes oxygenated, it muft fol-
low, that, if this portion fhould meet and combine with a
metallic oxyde, the falt formed by fuch an union mutt be
fuperoxygenated. But in the ftate of oxydation, doubtlefe,
is a great part of the iron which is fo abundantly diffufed
through the earth. Are.then the appearances in queftion
the refult of thefe circumftances? In fhort, are the falts
muriat of manganefe and oxygenated muriat of iron? In
purfuance of this idea I formed fome oxygenated muriat of

83 iron,

262 An Analyfis of two Mineral Springs .
iron, by mixing:fome yellow oxyde of iron (the rubigo ferrt

of the fhops) with water, and-expofing it, by ayproper appa-
ratus, to the oxygenated muriatic acid.gas. The gas readily
diffolves a part of the oxyde, a few bubbles (perhaps of.
carbonic acid) efeaping during the folution. 1. The falt
which is formed.is-deliquefcent ; colourlefs ; of a pure bit-
-ter tafte, without any of the-fweet aftringency of the com~
mon falts of iron*. Alcalies precipitate a white oxyde.
The mineral acids, alfo, decompofe the falt ; and at the fame
time a white matter, of a cryftallime form, precipitates, but
an excefs of acid re-diffolves the precipitate}. 2. If fome
metallic iron be digefted in a folution of this falt, an ochre
~precipitates copioufly, which is‘very-foluble in acids. Cop-
-per alfo decompofes the falt ; but the matter precipitated is in
‘{mall quantity, and hardly foluble in acids. 3. Pruffiat of
-pot-ath is totally unaffected by this falt; fo likewife is tinc-
-ture of galls when the falt is quite perfe& {; but, after iron
‘has been digefted with it, galls communicate a yellow tinge,
or even precipitate a -brownith- matter ; ftill the pruffiat of
potafh has no effect. . Thefe properties of the falt bear fo
{trong a refemblance to appearances which Ihave remarked
in the water, particularly in the effects of the metals (rv.
2 & 3.) and the failure of the re-agents (iv. 4 & 5.), that
it flrongly confirmed me in the hypothefis I had adopted.
On purfuing the experiment, however, the analogy failede
Tadded to the falt of iron very minute quantities of muriat

* By far the beft method of making this falt is to put the ruft in a fau-
eer, and to put the mixture of manganefe and muriatic acid, diluted to
avoid a ftrong effervefcence, in a cup on the fame faucer ; then to cover the
cup with an inyerted glafs: thus the axygenated vapour will be confined
as it is flowly extricated. If diftillation is ufed, the falt can be-hardly
‘made free from an aftringent tafte.

+ The fulphurie acid does not re-diffolve the precipitate ; the others dr.

Some further remarks on this fubje€t will be found (xiv. 6.).

+ I once faw the galls form a white precipitate ; but I fufpect the oxy-
pe was contaminated with fome common muriatic acid, formed by its
decompofition during the digestion,

of

ai Lemington Priors. 263

of Seren: but how {mall foever,was the quantity ufed,
and however much it was diluted, the manganefe was in-
ftantly deteSted by pruffiat of pot-ath. I was therefore forced
to conclude that, if oxygenated muriat of iron is really an in-
gtedient of this water, it muft be formed by a procefs dif-
ferent from that which I had imagined.

VIII. THE APPEARANCES IN QUESTION ARE PRODUCED
._ BY THE ACTION OF HEPATIC GAS ON IRON AND MAN=
GANESE.

An obfervation of Bergman, though in part erroneous,
has conduéted me, as I think, to the true caufe of thefe ap-
pearances; and I am greatly miftaken if its confequences,
when fully purfued, are not of confiderable importance to.
chemical feience. Bergman has afferted that hepatifed water
in which iron filings have been kept for fome days, in.a well-
clofed veffel, grows purple with tinCture of galls: if the iron
be diffolved by an acid, the colour approaches more to violet.
He moreover adds, that the folution of iron in hepatifed. wa-
ter is not at all rendered turbid by pruffiat of potafb (Bergman's
Effays, Differtation vu. 4. L.) This latter fact promifed to
throw fome light on the fubjeét of my enquiry, particularly
when it was joined to the fat of the hepatic {mell, which
the water has when recently drawh (1.). I was the more
ftrongly induced to pay attention to this combination, from
ahe contradition of another very eminent chemift. Mr.
Kirwan has denied that hepatic gas can diflolve iron, or any
other metal (Philojoph. Tranfac. 1786). To afcertain this
point, I have made numerous experiments with the greateft
caution and accuracy that I have been able to apply. The
hepatic gas which I have ufed, was obtained from fulphuret
of iron, formed by fufing equal parts of iron and flowers of
fulphur ; and (except in fome inftances, which will be _par-
ticularly noticed as they occur) was extricated by diluted
fulphuric acid. ‘The gas was colle€ted under water ; which
method was preferred, to purify it if ‘poflible from extraneous

$4 acid,

264 An Analyfis of two Mineral Springs
acid. 4. Idigeftei iron filings, previoufly purified by rep

peated wathings with diftilled water, ina folution of hepatie

gas in diftilled water: the boitle was filled with the folution,
and corked. The iron was prefently aéted upon; numerous
bubbles arofe, which drove the cork out of the bo:tle; they
were ftrongly inflammable, and probably, therefore, pure
hydrogen gas: the liquor gradually loft its hepatic odour;
and at the end of fome days it had a fmell a good deal re-
fembling that of ftagnant rain water; as the bubbles ceafed
to be produced it recovered its tranfparency. The liquor
was then examined by re-agents. Infufion of galls ftruck a
yellow tinge ; pruffiat of potath gave a little whitith cloud;
nitrate of filver and muriat of barytes, each very minute pre-
cipitates; pure potafh a yellow precipitate, but not till the
liquor had ftood an hour or two. The liquoy does not de-
pofit any thing, either by expofure to the atmofphere or by
a boiling heat: but by this laft procefs fomething, perhaps

a little gas which has efcaped the ation of the iron, flies

off; fince the precipitate with nitrat of filver was white af-
ter the boiling, which had previous to it been black. Very
little can be deduced with certainty from thefe trials, except
the prefence of a little fulphuric acid. It feemed of confe-
quence to determine whether this is generated in the pro-
cefs, or is accidental from the fulphuric acid which was
ufed to extricate the gas.

2. To determine this point I repeated the experiment,

ufing the muriatic acid to generate the gas, inftead of the
fulphuric. In this cafe, the liquor, as Bergman has faid, is
not at all rendered turbid by pruffiat of potafh; neither does
the muriat of barytes precipitate any thing: the precipitate
by pure potafh is now white, but as minute as before: ni-
trat of filver makes a yellow cloud both before and after
boiling : infufion of galls {trikes a yellow tinge. Hence it
is clear, that hepatic gas, when produced by fulphurie acid,
carries with it a little of the acid which cannot be feparated
by pafling it through water. It feems probable alfo, that a

little

ai Lemington Priors, 26¢

fittle muriatic acid is carried up in like manner when this is
ufed to extricate the hepatic gas. We may farther conclude,
that though the remark of Bergman on the effect of the
pruffiat of potafh is true; the remark which accompanies it
(on the colour preduced by infufion of galls) is erroneous.
A purple colour is always, I believe, occafioned by extra-
neous acid; in which cafe the pruffat of potafh is alfo pre-
cipitated. From the fame fats we are enabled to dete&
another error alfo, into which the fame great man has been
betrayed. In his analyfis of the acidulous waters of Medvi,
in Oftro-Gothland (Bergman’s Effays, Differtation vu. 6.),
he has noticed a refiduum of 44 grains of iron, diflolved
partly by hepatic gas, partly by carbonic acid. Now we
have feen that there is no decompofition of thefe liquors by
boiling ; nor does any oxyde precipitate, how long foever
the evaporation be continued. The hepatic gas feems to
be totally decompofed: nitric acid dropped into thefe li-

‘quors precipitates nothing.

Are we then to conclude with Mr. Kirwan, that hepatic
gas does not decompofe iron or any other metal? As the
gas itfelf is decompofed, this, in ftri€t propriety of language,
muft be allowed to be true; but that fome folution is
effe&ted during the decompofition the following remarks
evince. 3. A piece of clean and bright iron was put into
fome of the hepatifed folution (if I may be allowed. fo to
call it, while its true compofiticn is unknown) : it foon be-
came turbid ; a copious ochry precipitate fell down; and
in 24 hours the whole furface of the iron was covered’ with
ruft. 4. Let the folution be boiled in a copper veflel, a
precipitate alfo feparates of an ochry colour ; but it is fmall-
er in quantity than in the former experiment. 5. Digefta
piece of clean iron in the folution after it has been boiled in
a copper veffel ; much ochry matter {till feparates ; but there
is no veltige of metallic copper on the iron plate. 6. Di-
geft copper filings in the liquor in which iron filings have
been previoufly digefted ; feparate the copper filings, and

now

266 An Analyfis of two Mineral Springs, &'c.

now let a piece of bright iron be put into the liquor ; in this
cafe, copper is depofited on the furface of the iron ina me-
tallic ftate. 7. Puta fmall piece of fulphat of argill into a
glafs of the folution, after frefh iron filings have been di-
-gefted in it; a white ftratum forms at the bottom of the
glafs, but after fome time it is re-diffolved, and the liquor
refumes its tranfparency. 8. Put alittle oxygenated muriat
of.mercury into a glafs of the hepatifed folution ; as it dif-
dolves, a white matter colleéts on the fides, and falls to the
bottom of the glafs. 9. Intufion of galls, after the frefh iron
has been digefted with the folution, precipitates the iron of
a dark colour ; {till the pruffiat of potafh does not become
turbid. From all thefe faéts it is clear, that as the iron com-
‘bines with the fulphur of the hepatic gas, a peculiar fubftance
4s formed and diflolved in the water, which has hitherto been
unnoticed by chemical writers, as far as has fallen within my
information, That this fub{tance is contained in the waters
of the fpring under our prefent examination, feems' fully
eftablifhed by the concurrent evidence of fo many pheno-
mena in which they completely coincide. Compare m1.
r& 2. ty. 1, 2, 3,4, & 5.

FX. MANGANESE EXPOSED TO HEPATIC GAS.

To complete the demonftration, it is neceffary to examine
the action of hepatis gas upon manganefe.
1. I digefted fome black oxyde of manganefe in hepatifed

water: it had been previoufly purified, by being boiled re- a

peatedly in diftilled water*. The hepatic fmell of the gas
is quickly impaired; and in 24 hours, if enough of the oxyde
has been ufed, it is perfectly deftroyed ; ftill the liquor has a
peculiar {mell, which can hardly be called offenfive: no gas
is extricated in this procefs. ‘The liquor, after filtration, was

* The readicft method of purifying this fubftance is.to boil it firft ina

_very large quantity of rain water; after which, a fingle boiling in ea Bt

water will be fufficient to extraét every /olub/e impurity.

4

Origin of the Muriatic Acid. "267
examined by the fame re-agents as the +hepatifed {olution of
jron (vit. 1.) with nearly a fimilar refult ; a minute quan-
‘tity of fulphuric acid was deteéted; -prufliat of potath gave

_ a fmall white cloud ; tinéture of galls a flight yellow tinge.
Repeating the experiment with gas extricated by the muriatic
acid, there was, in this cafe, no trace of fulphuric acid, and
the liquor was not at all rendered-turbid by pruffiat of pot-
afh. From both thefe folutions pure potath feparates a very
minute white precipitate. 2. But, in one refpeét, thefe fo-
lutions differed from the folutions of irons for, by thefe,
nitrat of filver is inftantaneoufly decompofed, and a copious
‘precipitate feparates ; it is of a dark brown or yellow colour,
as if from a combination of fulphur. Oxygenated.muriat of
mercury let fall a white matter, much more plentifully than
from the folutions of iron. Tartrite of potath is decompofed,
and a fine ¢ryftalline fubftance is feparated, which is the tar-

- trite of manganefe.

3. This folution is affeéted by metals in a manner fimilar,
fo the folution of iron. A piece of clear iron becomes
quickly covered with ruft, and an ochry matter feparates. If
the liquor be boiled in a copper veffel, fome matter alfo
feparates of the fame colour, and the furface of the veflel is
evidently aéted upon, Thus the analogy between thefe
hepatifed folutions and the water of this {pring appears to
me completely eftablifhed; and it may be concluded that
this water contains a triple compound, the bafis of which is
‘iron and manganefe,.and the t telotian of which is effeCted by
hepatic gas.

%- ORIGIN OF THE MURIATIC ACID.

The coincidence between the artificial produéts and the

natural waters of the :{pring is fufficiently proved: another

coincidence remains to be confidered, much more interefting
‘and more unexpe&ted—the coincidence between the hepa-
“tifed folution of iron and the oxygenated muriat of iron. I
had almoft concluded, from thg refemblance between the
propertics

268 _ Origin of the Muriatic Acid.
properties of this falt and the phenomena of the water, thet
the water contains this very falt: now, I conclude, that they
contain a matter, be it what it may, produced by the aétion
of hepatic gas on iron. But they are the very fame fa@s
which form the bafis upon which each feparate inference
is built :—does it not then follow as a neceffary confequence,
that the hepatifed folution itfelf contains a muriat of iron
highly oxygenated, and that, therefore, in this proce/s muriatic
acid is generated? This cenclufion feems authorifed by
reafon, and experiment has confirmed it. 1. I evaporated a
{mall quantity of the folution (vil. 1.) in a watch glafs to
drynefs: a bitter deliquefcent falt is left behind: on this
falt a little trong fulphuric acid was dropped, and paper
moiftened with ammoniac was held over the glafs; white
vapours were immediately formed over the glafs: fome
volatile acid is, therefore, feparated by the fulphuric acid.
2. | evaporated about 8 ounce-meafures of the fame liquor,
- and, as beiore, cropped a little fulphuric acid on the re-
fiduum 5 in this cafe a ftrong effervefcence was excited, very
_ pungent acid fumes aiofe, which, from their f{mell, were
readily known to be muriatic. The fame truth was efta-
blifhed beyond a doubt by holding a bit of paper moiftened
with fimple water, which made the vapours vifible in the
form of a grey fmoke—a diftinguifhing characteriftic of the
muriatic acid. (Bergman’s Effays, Differtation \1. 11. b. 3-)
‘The evaporation had been performed in a copper veflel, ex-
cept at its clofe; and though it was carried on very rapidly,
the deliquefcent matter had acquired a flrong cupreous tafte.
3. The hepatifed folution of manganefe (1x. 1.) evaporated
to drynefs, leaves a deliquefcent falt of a peculiar mawkith .
tafte; and it fhews the fame figns of muriatic acid as the
folution of iron, when treated with fulphuric acid in the
fame way. I have expofed black oxyde of manganefe to
* oxygenated muriatie acid, and find that a deliquefcent falt is
formed, which is affeCted neither by prufhat of potath nor
tindture of galls ;—alkalies feparate from it (what I did not
5 expect

>

. Miafurement of the Meridian. 264
expect) white precipitates; tartrite of potafh, a cryftalline
infoluble falt: all properties refembling the hepatifed folu-
tion of manganefe. 4. Common iron rult, purified by boil-
ing in diftilled water, was digefted in hepatifed water. In
a day or two the hepatic odour is deftroyed, and the liquor
has properties fimilar to that which was formed with the
iron filings. The fame kind of deliquefcent falt is left by
evaporation, fhewing the fame appearances of muriatic acid.
However, this liquor refembles the folution of manganefe in
precipitating nitrat of filver readily, and of a brown colour
(ix. 2.). 5. I treated mercury in the fame way: no gas
efcapes in this experiment, as it does with the iron; a black
fubftance is formed ; but the hepatic odour was not deftroyed,
though the hepatic gas was kept in contact with the mercury
many weeks. After filtrating the liquor, I boiled it to expel
the fuperfluous hepatic gas. A {mall portion of the liquor
was fuffered to evaporate fpontaneoufly: a cryftalline matter
was left behind of an acrid tafte.. Another portion was
evaporated, with intention to collect more of thofe cryftals;
but, by accident, it was left expofed to heat too long, by
which it became perfeftly dry, and the refiduum became
quite black. A little fulphuric acid was dropped on this
black matter, by which it effervefced ftrongly, and very
pungent fumes arofe which had ail the properties of muri~
atic acid. ;

[To be conclided in the next Number. |

VIL. Method employed between Melun and Lieufaint in Francey -
to meafure the Bafe of a Triangle, in order to detérmine
the Length of an Arc of the Meridian. From the Journal —
de Phyfique, 1798. |

Tue high road between Lieufaint and Melun has lately
been the theatre of an operation extremely interefting, which
will form an epoch in the hiftory of the fciences. In’ order
; go

270 Method employed in Franc ;

to fix invariably the ftandard of the metre *, two celebrated
aftronomers, Delambre and Mechain, were commiflioned to
meafure an acre of the meridian, by a feries of triangles
carried from Dunkirk to Barcelona}. To calculate the fides
of thefe triangles, it was neceflary to fet out from a primitive
bafe. None of thofe meafured for the meridian of 1740
had been determined with fufficient accuracy, and fome
errots were fufpeCted. As the bafe teareft to Paris, berween
Villejuif and Juvify, préfented a length of little more than

5000 toifes {, with confiderable inequalities of the ground 3
the road from Lieufaint to Melun, which gave a length by

eftimation of 6076 toifes, in almoft a ftraight line and with
very little variation in the level, was with great reafon pre-
ferred. To prepare for the meafurement of this bafe, the
two fignals or obfervatories, now to be feen, the one at the
end of Lieufaint, and the other at the entrance of Meluny
were firft erected. Within each of thefe fignals a large
ftone was fecured in a piece of {trong mafon-work, and from
this flone arofe a cylinder of copper, faftened into it with a
mafs of lead. The axes of thefe cylinders, which were
fourteen lines. in diameter, correfponded perpendicularly
with the upper points of the fignals. As the line of the bafe
formed towards the middle a {mall bending, the angle was
meafured, and found to be 179° 115 which produced in the
total length a difference of 10} inches. Departing from the

* Sce the preceding table of the new French meafures. Eprr.
It was propofed to extend this labour to Majorca; but it was found

impoffible to proceed to that fation, on account of the too great diftance »

of the fignals.
£ The obje€&t of Delambre and Mechain’s labour being to eftablifh 2
relation between the old andthe new -meafures, and this labour having
been begun in 1791, it was neceffary that the meafurement fhould be ex-
pfeffed in toifes, and fra€tions of a toife; the ufe of which ‘could not be
abandoned till the metre was exactly determined. The comiiffion of
weights and meafures gave, according to the ancient mode of calculation,
a provifional metre, the approximation of which is more than fufficient for
common ules. This metre furpaffes the half toife by 11.44 lines.
fummit

—=

ae

to meafure an Are of the Meridian. 275

fummit of this angle, poles in the direction of each of the
fignals were erected, at the diftance of every hundred toifes.
At the bottom of each’ of thefe poles, a wooden wedge was
driven into the ground to fuch a depth that nothing could
alter its pofition, and the place of each of the wedges was
marked by heaps of ftones difpofed along the road.

After thefe preliminary labours, Delambre began the ope
ration of meafurement on the sth of Floreal, at the bafe of
the fignal of Melun. The inftruments conftructed for this
purpofe were four rules of platina, each two fathoms in
length (at 2 given temperature) 5 fix lines in breadth, and
two thirds of a line in thicknefs. Each rule was mounted
or a piece of wood, {ufficiently ftrong to be fecure againft
- all warping and bending; and was covered, at the diftance
of three inches, with a flight cafe of wood, at the two
extremities of which arofe two points made of iron, to ferve
as marks to direét the fight. On the rule of platina there
was placed another rule of copper of the fame ftrength, but
fomewhat lefs in length, which ferved to meafure the ex-
panfion of the platina. It is well known by experience, that
the expanfion of platina is to that of copper as 12 is to 25.
The two rules were fixed upon each other, in an invariable
manner by their anterior extremity, in order that the effec
of the expanfion might be carried entirely to the other ex-
tremity. The rules being plunged into melting ice, and
confequently at o° of Reaumur’s thermometer (32° Fahr.),
the extremity of the copper coincided on the platina at a line
marked; but as foon as they were expofed to another tem-
perature, the copper extended on the platina, on account of
thre different expanfion of the two metals. An ingenious
apparatus conftruéted on this principle, afforded, with the
affiftance of a nonius and microfeope fitted to it, the means
of eftimating the dilatation of the platina to nearly ssc000
of atoife, ‘This apparatus formed at the fame time a very
fenfible metallic thermometer, each part or degree of which
correfponded to a dilatation of 0,0c0009245 of a toife, on

each

292 _ Method employed in. France

éach rule of the platina*. The four rules were olaced dt
the end of each other, fupported’ by iron tripods mounted or
three ferews, to make the extremities correfpond at equa
licights, and brought into a line by marks to direét the fight,’
placed fucceffively on the wooden wedges before mentioned.
Had each rule been placed in immediate contact with itsneigh-
bour, the operator in placing one rule might have deranged
the preceding, and the contact befides would never have
been perfeét. To prevent this inconvenience, care was taken’
to leave a fufficient interval from one rule to another; but
the extremity of each rule was furnifhed with a fmall rule,
ér flip of platina, which could be pufhed into a groove to fill
up the interval, and to form a perfect conta with the fol-
lowing rulé: a feale fitted with a nonius, viewed through a’
microfcope, meafured the length of the {mall rule, to nearly
¢oceoe Of a toife. ‘But in thus meafuring:a line on ground,
which ofteri rifes of falls infenfibly, it was neceflary to pay
great attentiom to the differences of the level. For this pur-
pofe the cafe of each rule had, at equal diftances from its
extremities, two fmall cubes made of copper, which rofe to
equal heights om the plane of the rules; and upon which
were laid the two branches of a {quare, bearing a fpirit level.

This level being twice placed on each rule, in the two con-
trary direétions, gave the mean inelination almoft to a
minute; fo that with a very fimple formula each meafure
was found reduced to the horizontal line, and the feries of
obfervations gave at the fame time the complete level of the
bafe. In commencing the operation, the firft rule was
placed in fuch a manner that the centre of a plummet, fuf-
pended at its anterior extremity, fhould fall exactly on the
centre of the copper cylinder, already mentioned, which

® Allufion is made heré not to common thermometers, but to newly:

invented metallic thermometers, divided according to a new decimal feale,
of which 2.316 parts correfpond to one degree of Reaumur. To exprefs;

therefore, that degree of expanfion of the platina, o,000009245 mutft be’

multiplied by 2,316, which gives a little mere than o.eco02,

- formed

j

%o meafure an Arc of the Meridian. 273

- €ormed a point of departure under the fignal of Melun. The ;
tules 2, 3 and 4 were placed in a feries after the firft, and
brought into a line with the fight. The {mall rules, or flips,
were pufhed in to fill up the intervals; and the lengths of
thefe flips, as well as the expanfion of each rule, and the
obfervations of the level, read by Delambre, were written, as
he di€tated, by two affiftants, who each held a paper divided
into columns for that purpofe. After this the firft rule was
removed and placed after the fourth rule, and the fame ope-
ration was repeated, direCting the line always by the fight-
~ points, removed fucceffively at the diftance of every hundred
toifes, and taking care at each change of the rule to read the
expanfion, the length of the flip, and the two obfervations of
the level. Laat
This operation being repeated 3021 times, rendered it
confequently neceflary to make 6042 obfervations by the mi-
crofcope, and as many of the level. This was continued
without interruption during the day ; and when night ebliged
the operators to fufpend their labour, the following method
was employed to fix the point where they left off, and which
was to ferve next morning for the point of departure. To-
wards the extremity of the laft rule an iren ftake was funk
into the ground, and a pretty deep hole dug around it. The
iron fiake was then removed, and its place fupplied by a
wooden ftake, on the furface of which was nailed a plate of
fead. The laft rule was placed in fuch a manner that 2
piummet, nicely adjufted and fufpended from its extremity,
fhould fall on this plate ; the point where it touched the lead
was marked as exactly as poffible, and the wooden ftake
was defended by a flrong covering of wood, which was itfelf
covered with earth, fo that carriages could pafs over it with- .
out caufing any derangement. ‘Fhings remained in this ftate
fill next morning, when the operations were refumed in the
like manner as that of the firft day. The whole operation
lafted forty days, three of which only were interrupted.

_ The operators generally advanced eighty-eight lengths of

Voi. I. 7 the

.

274 On the Effect of Mordants 3
the ruleeveryday. On the !5th of Prairial at noon, Delambre
arrived at the cylinder of copper, forming the other extremity
of the bafe, under the fignal of Lieufaint ; the extremity of the
laft rule was found to pafs the centre jufl 48! lines; and this
deduQion being made, as well as all the neceffary calcula-
tions, the refuit was a length of 6075,784589 toifes.
‘Though thefe details are fufficient to enable the reader to
judge of the great precifion employed in this operation, De-
Jambre added: many other ingenious and nice precautions
which are too long to be repeated here, and which enfured
_to his labour the highelt degree of exa€tnefs poflible. We
fhall only add, that, by the accuracy of the initruments and
methods employed, errors of inches and feconds are as Kittle
to be prefumed in the prefent meafurement, as errors of
toiies and minutes were formerly. ‘This great perfe€tion is
chicfly owing to the labours of Borda.

VIII. Cremical Reflections on the Effe® produced by Mordants in
dyeing Cotton red. By. 7. A. CHapraL. From the An-
nales de Chimie, Vol. XXVTI.

Ty regard to the beautiful red colour given to cotton by
means of madder, the cafe is the fame as with certain phar-
maceutic preparations, the ridiculous receipts for preparing
which have been hiiherto refpected, becaufe apprehenfions
have been ent rtained that their effect would be altered by
_ introducing the lealt change in the procefs. A month’s la-
bour would fcarcely be fufficient to terminate all the opera-
tions which have been judged indifpenfibly neceffary for ob-
taining that beautiful colour called the Turkey or Adri-
anople red. Soda, oil, gal} nuts, fumach, the fulphate of
alumine, blood, the gaftric liquor, madder, foap, the nitro-
muriate of tin, are employed in fucceflion. The true means
of fimplifying t'is procefs is not to labour at hazard, and to
make trial of the different methods practifed without a

<

5 ; guide

———

in dyeing Cotton red. 275
guide and without principles. Such a proceeding conducts
rarely and with flow fteps ‘to any happy refults. I am ac-
quainted but with one method of making progrefs in the
arts, which is, to bring back and reduce all operations to
fimple principles: by thefe means we obtain fixed points of
departure, to which all refults and all our labours may be
referred. Chemiftry is now fufficiently advanced to fupply
us with thefe bafes, and nothing therefore is neceflary but to
eftablifh them. In the hands of the artift they will become
‘what formule are in the head of the mathematician. I
fhall therefore attempt to give an example by fubjeCting to
chemical principles the three chief mordants in dyeing cot-
ton red; viz. oil, gall nuts, and alum.

It is known that cotton does not receive the red of mad-
der in a fixed manner until it has been properly impregnated
with oil. The red applied by printing is far from poffeffing
the fame degree of fixity, fince it will not ftand when wafhed
with foda. This preliminary preparation is given to cotton
by forming a cold foapy liquor from the combination of oil
and a weak folution of foda. The ufe of this alkaline ley is
attended with no other advantage than that of diluting and
dividing the oil, and enabling the operator to convey it to
all the parts of the corton in an equal and eafy manner. I
have found by experience that potafh produces the fame ef-,
fect as foda ; and, in my opinion, this faét merits fome con-
fideration, as foda, which is fearce and dear in the north,
may be fupplied by potafh, which is there common.

* From this principle it follows, that all kinds. of foda or oil
cannot be employed indifcriminately. In order that the foda
may have the proper qualities, ir muft be cauftic, and con-
tain little muriate. It muft not be rendered cauftic by lime,
as it then makes the colour brown. Its caufticity muft be
the effect of its calcination.

The carbonate of foda, and foda mixed with much mu-
riatey combine with oil but very imperfe@ly. Therefore

; , ine foda

276 On the Effect of Mordants
foda that has been long prepared, or is impure, cannot bg.
applied to the purpofes of dyeing in this manner.

The choice of the oil is equally effential as that of the foda,
The oil, to be good, muft unite very perfectly with the ley
of foda, and muft remain in an abfolute and' permanent ftate
of combination. The oil fitteft for this dye is not fine oil,
but that rather which contains a large portion of the extrac-
tive principle. The former does not preferve its ftate of -
combination with the foda, and requires fuch a ftrength in
the ley as would be injurious to the fubfequent operations.
The latter forms a thicker and more durable combination,
and requires only a weak ley of one or two degrees.

The neceflity of producing a perfec and intimate combi-
nation of the oil and the foda will be readily perceived, by
reflecting that the ley of foda is only employed to divide,
dilute, and convey the oil in an equal manner to all the
parts of the cotton: for it follows from this principle, that
if the oil is not well mixed, the cotton made to pafs through
this mordant will take the. oil unequally, and the colour,
therefore, will be badly united. Hence it happens that
the workman places the whole fecret of a well-united and
ftrong colour in the choice of good oil and fuitable foda.
It thence follows from thefe principles that the oil ought
to be in excefs, and not in a ftate of abfolute faturation ; for,
in the latter cafe it would abandon the fa in wafhing, sit
the colour would remain dry.

When the cotton has been properly impregnated with
oil, it is fubjected to the operation of being galled. The
ufing of the gall nuts is attended with feveral advantages :
1. The acid which they contain decompofes the faponaceous
liquor with which the cotton is impregnated, and fixes the
‘oil.on the ftuff. 2. The charaéter of animalifation which
the galls have, predifpofes the cotton to receive the colour-
ing matter. 3. The aftringent principle unites with the oil,
and forms with it a compound which blackens as it dries ;

which

in dyeing Cotton red. 297

which is not very foluble in water,and which has the greateft
affinity with the colouring principle of the madder. The
dyer may acquire a competent knowledge of this laft com-
bination, and ftudy its properties, by mixing a deco€tion of
gall nuts with a folution of foap.

It follows from thefe principles: 1. That the place of the
gall nuts cannot be fupplied by any other aftringent, let the
quantity employed be what it may. 2. That the galls ought
to be {trained as hot as poflible, that the decompofition may
be fpeedy and perfe@. 3. That the galled cotton ought to
be {peedily dried, in otder to prevent its affuming a black
colour, which would injure the brightnefs of the red intend-
ed to be given to it. 4. That dry weather ought to be
chofen for the procefs of galling, becaufe in moift weather
the aftringent principle communicates a black colour, and dries
flowly. 5. The cotton ought to be preffed together with the
greateft care, in order that the decompofition may be ef-
feéted in an equal manner at every point of the furface.
6. That a proportion ought to be eftablifhed between the
gall nuts and the foap: if the former predominates, the co-
Jour is black; if the latter, the portion of the oil not com-
bined with the aftringent principle then efcapes by the wafh«
ings, and the colour remains poor.

The third mordant employed in dyeing cotton red is the
fulphate of alumine (alum). This fubftance not only has
of itfelf the property of heightening the red of madder, but it
contributes alfo by its decompofition and the fixation of its
alumine to give folidity to the colour. To judge of the ef-
fects of alum in dyeing cotton, it will be fufficient to mix a
decoétion of gall nuts with a folution of alum. The mixture
becomes immediately turbid, and there is formed a greyith pre-
cipitate, which, when dried, is infoluble in water and alkalies.

Every thing that takes place in this experiment of the la-
boratory may be obferved in the procefs of aluming in dye-
ing. Cotton, when galled and plunged in a folution of the

tulfate or acetite of alumine, immediately changes its colour,
Tq and

278 On the Effet of Mordants, €5'c.

and becomes grey ; the bath prefents no precipitate, becaufe
the operation takes place in the tiffue of the cloth itfelf,
where the produétion remains fixed. It is however to be
obferved, that if the galled cotton be paffed through a too
warm folution of alum, a portion of the galls efcapes from
the tiffue of the ftuff, and the decompofition of the alum
takes place in the bath itfelf ;, which diminifhes the propor-
tion of the mordant, and impoverifhes the colour.

We have here therefore a combination of three’ principles
(oil, the aftringent principle, and alumine) which ferve as a
mordant for the red dye of madder. Each of them employed
feparately produces neither the fame fixation nor the fame
luftre in the colour.

This mordant, without difpute, is the moft complex known
in dyeing, and it prefents to chemiftry a fort of combination
which it is of the utmoft importancé to fludy. It is from
the precifion in this combination, and the judgement fhewn

by the artift himfelf to, produce it, that a beautiful colour .

can be expected; but if it be poffible for him to condu&
himfelf through the labyrinth of thefe numerous operations,
by taking the clue of experiment as his guide, it will at any
rate be very diflicult for him to fimplify his progrefs, or bring
it to perfection. It is only by reafoning on his operations, and
calculating the refult and principle of each, that he can hope
to become mafter of his proceffes, to corre& their faults,

and to obtain invariable products. ~ Without this, the ~

practice of the moft experienced artift will afford nothing in
his hands but the difcouraging alternative of fuccefs and dif-
appointment. - { withed therefore in this fhort analyfis of
the procefs for dyeing red, which is the moft complicated
ofall, to give an inflance of what chemiftry can do in the
arts when its principles are properly applied. I will venture
to aflert, that the moft uninformed workman will here find
the principle of hisart and the rule of his condué..

nie ‘ IX. On

a

IX. Ona new metallic Subftance contained in the Red Lead of
Siberia, to which it is propofed to give the Name of Chréme* on
account of the Property it paffeffes of colouring every Subjlance
combined with it. By M.Vauguezin. From the An-
nales de Chimie, Vol. XXV. ;

In proportion as the means of chemiftry are multiplied and
brought nearer to perfection, we have feen the number of
fimple bodies increafes Scheele enriched this feience with
two metallic fubftances and feveral acids, &c. and Klaps
roth lately has made known two new metals aiid two earths.
Tt appears, therefore, that we are not yet arrived at its ut-
mott boundaries; and, that when mankind fhall dig more
frequently, and to a greater depth in the earth, many bos
dies will be difcovered, of which at prefent we have no idea.
Iwill even venture to affert that when chemiftry, armed with
ail the means it p flefles at prefent, fhall get poffeflion of alt
the objects preferyed in cabinets with fo much care, as fo
many relicks which it is unlawful to touch, it will procure
ufeful difcoveries from bodies that at prefent excite only idle
curiofity.

In the year 1789 M. Macquart; a phyfician at Paris, tos
gether with myfelf, analyfed the red lead of Siberia, and
announced that this mineral was an intimate combination
of the fuper-oxygenated oxyde of lead and che iron of alu-
mine. Since that epoch Bindheim alfo faid, that he had
found init copper, cobalt, nickel, iron, and the molybdic
acid. Some days ago I likewife fubje€ted this fubftance to
a new examination, and: l hope to prove that ‘every thing
hitherto publithed on this fubjeét is incorrect; and though
I have not yet given to my refearches all the extent which I
propoe, for want of a fufficient quantity of matter, they
have been carried far enough to prove that the red lead cons
tains a new metallic acid poflefling charaterifing marks

* From xowme colour. Epit.

ol well

ma

280 On the new Metal called Chréme

well defined, and fome properties which may render it ap
plicable to the arts.

Exp. I. A hundred parts of this mineral reduced ti to a fine
powder, were mixed with 309 parts of the faturated carbo-
nate of potafh, and about. 4000 parts of water; and this
mixture was expofed for an hour to a boiling heat. 5 ob~
ferved,.1{t, that when thefe matters began to aét upon each
other there was produced a ftrong effervefcence which con-
tinued a long time; 2d, that the orange colour of the lead
became a brick red; 3d, that at a certain period the’ whole
matter feemed to diffolve ; 4th, that in proportion as the ef
fervefcence advanced the matter re-appeared under the form
ofa granulaied powder, of a dirty yellow colour; sth, that
the liquor affumed a beautiful golden yellow colour. When
the effervefcence had entirely fubfided, and appeared to
have ‘no longer any ation on the fubftances, the liquor
was filtered, and the metallic duft collected on the paper.
After being wathed and dried, it weighed no more than
78 parts : the potafh therefore had taken from it 22 parts.

Exp. 1. i poured upon the 78 parts juft mentioned, fome
of the nitric acid, diluted in twelve parts of water, which
produced a brifk effervefcence. The greater part of the
matter was diffolved : the liquor aflumed no colour, and
there remained only a {mall quantity of powder of an orange~
yellow colour. I feparated the liquor of the reiduum by
the help of a fyphon, wafied the matter feveral times, and
united the wafhings with the firft liquor. This refiduum,
dried, weighed no more than 14 parts: from which it fol-
lows, that the nitric acid had diflolved 64.

Exp. Uk. Tagain mixed thefe 14 parts with 42 parts of
the carbonate of. potath and the neceflary quantity of water.
I then treated them as in Experiment i. and the pheno-
mena were the fame. The liquor, after being filtered, was
united to the forme; and the refiduum, wafhed and dried,
weighed no more than 2 parts, which were ftill red lead,
and therefore thrown away.

Exp. IV.

found in the Red Lead of Siberia. 284

Exp. TV. The two nitric folutions united and evaporated,
produced g2 parts of nitrate of lead, cryftallifed in o€taedra,
perfectly white and tranfparent. Thefe 92 parts of nitrate

of lead, diffolved in water, were precipitated by a folution of
" the fulfate of foda. This produced 81 parts of the fulfate
of lead, which were equivalent to 56,68 of metallic lead.

Exp. V. The alcaline liquors united, had an orange-yel-
low colour. They depofited at the end of fome days two
parts of a yellow powder which contained no more lead.
Thefe liquors, fubjected to evaporation until a faline pellicle
was formed on their furface, produced, on cooling, yeHow
eryftals ; among which there was carbonate of potafh, not
decompofed. Thefe cryftals diffolved in water, and the
folution united with the mother water, the whole was
mixed with weak nitric acid until the carbonate of potafh
was faturated. The liquor then had avery dark orange-
xed colour. Being united with a folution of the muriate of
tin, newly made, it firft affumed a brown colour, which af-
terwards became gteenifh. Mixed with a folution of the
nitrate of lead, it immediately produced the red lead. Laft-
ly, evaporated {pontaneoully, it produced ruby-red eryftals,
mixed with cryftals of. the nitrate of potafh. Ninety-eight
parts of this mineral, decompofed as above mentioned, hav-
ing produced 81 parts of the fulfate of lead, 100 parts
would have given 82.65, which are equivalent to 57.1 of
metallic lead. But admitting, as experiment proves, that
100 parts of lead abforb, in combining with acids, 12 parts
of oxygene, the 57.4 of metallic lead ought to contain in
the red lead 6.86 of this principle, and we ought to have
for the mineralifing acid 36.4. :

_ xp. VI. To verify by fynthefis the proportions of the
principles of the red lead found by analyfis, I diffolyed 50
Grains or about 2.654 grammes of metallic lead in the nitric
acid; and the folution having been divided into two equal
_ parts, the one was completely precipitated by the neceflary

quantity _

~

282 On the new Metat called Chréme

quantity of the combination of the acid of red lead with pots
ath, and T obtained 23 grains, or about 2.282 grammes of
ted lead, as beautiful as the natural mineral. ‘The other
portion of thie nitrate of lead, precipitated by cauftic potath,
gave 28 grains of the white oxyde of Jead. Thus, by this
fynthefis, 100 parts of red lead would be compofed of 65.12
of the oxyde of lead and 34.88 of acid. By analyfis, as
has been fhewn, it gives only 1.72* lefs in theacid which
mineralifes the red lead—a difference which approaches as
near to corre€tnefs as chemical means will admir+.

Though the properties above fhewn were more than fufh-
cient, ftrictly fpeaking, to convince any one well acquainted
with.the differential characters of metallic fubftances, that
the one in queftion belongs to a particular {pecies, [ thought
it my duty to compare its acid by a fertes of combinations
with the molybdic acid, in fome properties of which it

feems to partake.

,

Comparative Experiments on the Molybdic Acid and that of:
Red Lead. The Combination of the former with Potafh is

diftinguifbed by the Letter A, and the Combination of the late

ter with Potajh by the Letter B.

The combination of the molybdic acid with potafh furs
nifhes a falt which has no colour. :

The combination of the acid of red lead with potafl
gives a falt of an orange colour.

A, Mixed with filings of tin and the muriatic acid, tmmes
diately becomes blue, and precipitates flakes of the fame

* There muft be amiftske in {ome of the cyphers; for the difference
between 36.4 given by analyfis, and 34.33 obtaiued by fynthefis, is only
3.52. Enir.

+ It is known by the experiments of C Macquart, that the red lead
of Siberia contains a finall quantity of the water of cryftailifation, whick
amounts to three or four centiemes. It may be poifible, therefore, that
this difference may be owing to that fubitance.

colour, —

io >.

-

Sound in the Red Lead of Siberia. 283

colour, which difappear at the end of fome time, if an ex-
cefs of muriatic acid has been added, and the liquor

_ affumes a brownith colour.

B, Treated in the fame manner, becomes at fitft yellow-

’ ifh-brown, .and afterwards affumes a beautiful green colour.

A, Mixed with a folution of hydro-fulfure of potafh, gives
Mo precipitate, but by the addition of fome drops of the
nitric acid there is immediately formed a precipitate of a
chefnut-brown colour. ;

_B, Mixed with the fame reagent, gives, without the ad-

‘dition of:the nitric acid, a green precipitate, which, by

that acid, becomes yellowifh.

A, With a folution of the nitrate of lead, forms a white
precipitate, foluble in the nitric acid.

B, Mixed with the fame folution, gives an orange pre-
Cipitate, abfolutely of the fame fhade as that of the red

lead pulverifed.

A, Mixed with a little alcohol and nitric acid, does not
change its colour.

B, Added to the fame reagent, immediately afflumes 2
blueifh green colour, which preferves the fame fhade even
after deficcation : ether alone gives it the fame colour.

A, With a felution of the nitrate of mercury, gives a
white flaky precipitate.

B, With the fame folution of mercury, gives a precipi-
tate of a dark cinnabar colour.

A, With a folution of the nitrate of filver, forms 2
white flaky precipitate.

B, With the fame reagent, gives a precipitate, ‘atl
the moment it is formed, appears of a moft beautiful car-
mine colour, but becomes purple by expofure to the light,
This combination, expofed to the heat of the blow-pipe,
melts before the charcoal is inflamed. It affumes a blackifh
and metallic appearance. If it be then pulverifed, the pow-
der is ftill purple; but after the blue flame of the lamp is
brought in contact with this matter, it aflumes a green co-

lowr,

284, On the new Metal called Chréme.

Jour, and the filver appears in globules difleminated through

out its fubftance. ~

A, With the nitrate of copper; forms a greenifh preci-+
pitate.. °

B, With the fame folution, gives a chefnut-red precipi-
tate. :

A, With the folutions of fulfate of zinc, muriate of bif=
muth, muriate of antimony, nitrate of nickel, the muri-

ates of gold and platina, produces white precipitates, wher

thefe folutions do not contain excefs of acid.

B, With the fame folutions, produces almoft the fame
phenomena ; except that the precipitates are for the moft
part yellowith. That of gold is greenifh.

The Molybdic Acid alone.

r. The molybdic acid melted with borax gives it 4
blueith colour.

2. Paper dipped in the molybdic acid becomes in the furt
of abeautiful blue colour. .

3. The molybdate of lead diffolves in the muriatic acid;
and the folution does not affume any colour even by ebul+
lition.

Acid of the Red Lead alone.

1. The acid. of the red lead melted with borax commus
nicates to it a very dark green colour.

2. Paper impregnated with the acid of red lead aflumes
in the light a greenifh colour.

3. The red lead diffolves even without the application of
heat in the muriatic acid, and the folution has an orange-
red colour; but by ebullition it aflumes a beautiful green
colour, and there is formed muriatie acid highly oxyge-
nated.

_From the phenomena above mentioned; I entertain no
doubt that the acid which mineralifes the red lead of Siberia

has for its bafis a particular metal, hitherto unknown. If ©
it be compared indeed with all the other metals, there will —
ae

a

Jumping Moufe of Canada. 283
be found no perfe&t analogy between them. The uranium
does not become acid; it cannot be combined with cauftic
alkalies, and does not redden vegetable blue colours. Tita-

“nium diffolves in acids, produces cryftallifable falts, and does

not combine with alkalies. _ Tungften becomes yellow in
acids, without being diffolyed’s and gives, with alkalies, white

9 eryftallifable faits. It would be ufelefs to continue the com-

parifon of this fubftance with other metals; their properties
are too well known; and it is evident that a exhibit no

_ phenomena of the like kind.

[M. Vauquelin’s fecond memoir on the properties of this
new metal will be given in the 1 next number of the Philofo-
et Magazine. ]

&- An Account of the Jumping Moufe of Canada, Dipus
“ Canadenfis. By Major General THomas DAri&s, F.R.S.

and L.§. From the Tranfaétions of the Linnean Society,
Vol. IV. 1798.

As I conceive there are few perfons, however converfant
with natural hiftory, who may have feen or known there
was an animal exifting in the coldeft pares of Canada, of the
fame genus with the Jerboa, hitherto confined to the warmer
climates of Europe and Africa; I take the liberty of laying
before this fociety the following obfervations (accompanied ~
by a drawing) on an animal of that kind, procured by myfelf

in the neighbourhood of Quebec, during my laft refidence in

that country. As I do not recolle€t to have feen this animal
either figured or defcribed by any author in natural hiftory,
I flatter myfelf, thefe obfervations may afford fome fatisfac-
tion to the prefdent and members of the Linnean Society.

The fpecimens from which I made the drawing are now in

my collection. With refpect to the food, or mode of feed-
ing, of this animal, I have it not in my power to fpeak with
‘any i of certainty, as I could by no means procure any

kind

‘

286 - Fumping Moufe of Canada.
kind of fuftenance that I could induce it to eat; therefore,
when caught, it-only lived a day anda half. The firft I was
fo fortunate to catch was taken in a large field near the falls
of Montmorenci, and by its having ftrayed too far from the
fkirts of the wood, allowed myfelf, with the affiftance of
three other gentlemen, to furround it, and after an hour’s
~hard chafe to get it unhurt, though not before it was
thoroughly fatigued; which might in a great meafure ac-
celerate its death.

During the time the animal remained in its ufual vigour,
its agility was incredible for fo {mall a creature. It always
took progreflive leaps of from three to four, and fometimes
of five yards, although feldom above 12 or 14 inches from the
furface of the grafs; but I have frequently obferved others
in fhrubby places and in the woods, amongft plants, where
they chiefly refide, leap confiderably higher. When found
in fuch places, it is impoflible to take them, from their won-
_ derful agility, and their evading all purfuit by bounding into

the thickeft cover they can find.

With refpe& to the figure given of it in its dormant flate,
I have to obferve, that {pecimen was found by fome work-
men, in digging the foundation for a fummer-houfe, ina
gentleman’s garden about two miles from Quebec, in the
latter end of May 1787.

It was difcovered enclofed in a ball of clay, about the fize
of a cricket-ball, nearly an inch in thicknefs, perfeCtly {mooth
within, and about 20 inches under ground. The man-who
fir difcovered it, not knowing what it was, firuck the ball
with his fpacde, by which means it was broken to pieces, or
the ball alfo would have been prefented to me. The draw-
ing will perfe&tly fhew how the animal is laid during its

. dormant flate.

How long it had been under ground it is impoffible to

fay; but as I never could obferve thefe animals in any parts

of the country after the beginning of September, I conceive -

they lay themfelves up fome time in that month, or beginning
of

:
:

.

The-ry of Cryftallifation. 289
of Odtober, when the froft becomes fharp: nor did I ever
fee them again before the laft week in May, or beginning of
_ June. From their being enveloj ed in balls of clay, without
any appearance of food, I conceive they fleep- during the
winter, and remain for that term without fuftenance. As
foon as [ conveyed this fpecimen to my houfe, I depofited
it, as it was, in a fmall chip-box, in fome cotton, waiting
with great anxiety for its waking; but that not taking place
at the feafon they generally appear, I kept it until I found it
begin to fmell: I then ftuffed it, and preferved it in its torpid
pofition. I am led to believe its not recovering from that
ftate, arofe from the heat of my room during the time it was
in the box, a fire having been conftantly burning in the
ftove, and which in all probability was too great for refpira-
tion. Iam led to this conception from my experience of
the {now bird of that country, which always expires in a few
days (after being caught, although it feeds perfectly well)
if expofed to the heat of a room with a fire or ftove; but
being nourifhed with fnow, and: kept ina cold room or paf-
fage, will live to the middle of fummer.

The animal above defcribed belongs to Schreber’s genus of
Dipus, and may be characterifed

Dirvus Canavensis palmis tetradcdylis, plantis pentadadylis,
gaudd annulatd undique fetosd, corpore longiore.

Fig. 1. Plate VIII, reprefents the Dipus Canadenfis.

Fig. 2 fhows it in its torpid ttate.

AI. On the Theory of the Structure of Cry/fals, by the Abbé Haur.
From Vol. XVII. of the Annales de Chimie.

[Continued from Page 169.]

4. Intermediate Decrements.

Turret are certain cryftals in which the decrements on
the angles do not take place in lines parallel to the diagonals,
: ; but

288 Theor ‘y oF Cryftallifation:

but parallel to lines fituated between the diagonals and the
edges. This is the cafe when the fubtrations are made by
ranges of double, triple, &c. moleculz. Fig. 47, (Plate IX.)
exhibits an initance of the fubtractions in queftion; and it
is feen that the molecule which compofe the range repre-
fented by that figure, are afforted in fuch a manner as if of
two there were formed only one; fo that we need only to
conceive the cryital compoted of parallelopipedons, having
their bafes equal to the fmall re€tangles abcd, edfg,
gil, &c. to reduce this cafe under that of the common -
decrements on the angles. I give the name of intermediate
decrement to this particular kind of decreafe, the progrefs of
which will bé betier iliuitrated by the following example.
Sywitalic Iron Ore (Fig: 48).

De Ville Cryftail-graphic, tom. ui. p. 198 and 199. war. 9
and to.

Geomet. chara&. Refpective inclination of the trapeziums
bc go, N92; of the’ rifing: pyramids. 135° 34° 3175
of the edges eg, gq, 129° 31’ 10". Sane of the tra-
pezium bego, bore = 103° 48! 35; o or g = 76° 11
25".

This variety of iron ore, which forthe moft part appears un-

?

der the formof two oppofite pyramids, rifing from a common

bafe, is found at Framont in les Vofges. There are fome

groupes the furface of which, like the iron ore of the ifland of

_ Elba, refle&ts the moft lively prifmatic colours. The cryftals

are often fo fmall, that they might be taken for fimple tetra
gonal laminz; but, on clofe infpedtion, the {mall {pots which

form the faces of the rifing pyramids may be. feen.

Thefe cryttals, which M. de l’Hle claffed among the modi-
fications of the dodecaedron with ifofceles triangular planes,
have for nucleus a cube which performs the fundtions of the
rhomboid, as in the ore of the ifland of Elba. The two
regular hexagons, by which they’are terminated, arife from
a decrement bya fingle range of cubic moleculz on the
angles c,n, (fig. 46) of the nucieus.

: To

Theory of Croftallifation. 289
~To form an idea then of the effect of the intermediary
law, combined with the preceding, and which gives rife to
the lateral trapeziums, let us fuppofe that chpr (fig. 49)
reprefents the fame {quare as fig. 46, fubdivided into fmall
fquares, which are the external faces of as many molecule.
If we take thefe molecule by pairs, fo that they form rectan-
gular parallelopipedons, having for bafes the eblong fquares
bagh, hgm G, &c. and if we imagine that the fubtractions
are made by two ranges of thefe double moleculz, the edges
of the laminz of fuperpofition will be fucceflively ranged in
lines, as PG, TL, Rp, Sp, kz, yz, &c. and the fum
of all thefe edges will produce two faces which, departing
from the angles 4,7, will converge, the one towards the
other, and will unite themfelves on acommon ridge, fituated
above the diagonal cp, but inclined to that diagonal. We
fhall then have twelve faces as the complete refult of the
decrement; and calculation fhews, that the fix fuperior faces,
beirg prolonged to the point where they meet the fix lower
faces, will form with them the furface of a dodecaedron,
compofed of two right pyramids united at their bafes ‘Thefe
pyramids are here incomplete by the effect of the firft law,
which gives the hexagon abcdru (fg. 48) and its op-
pofite *. a
5- Mixed Decrements.

In other cryftals the decrements, either on the edges or on
the angles, vary according to laws, the proportion of which
¢annot be expreffed but by the fraGtion + or 3. It may
happen, for example, that each lamina exceeds the following
. by two ranges parallel to the edges, and that it may at the
fame time have an altitude triple that of a fimple molecula.
Figure 54 reprefents a vertical geometrical fection of one of
the kinds of pyramids which would refult from this decre-
ment ; the effect of which may be readily conceived by con-

* The term /yn/aclic denotes the combination of decrements, one of
which rakes place by a finyle range of fimpie molecule, and the other by
two ranges of double molecule, ;

“ Vou. I, U fidering

260 2=—Ssi‘“ts*s*s*é«ST Aco of Cryffallifation.
fidering that AB is a Horizontal line taken on the upper bafe
of the nucleus, bagr the fection of the firft lamina of
fuperpofition, gfen that of the fecond, &e. I call mixed
decrements thofe which exhibit this new kind of exception
from the fimpleft laws. :
Thefe decrements, as well as the intermediary ones, rarely
exift any where elfe, and it is particularly in certain metallic
fubftances that I have difcovered them. Having tried to ap-
ply the ordinary laws to a variety of thefe fubftances, | found
fo great errors in the value of the angles, that I at firft
believed they were inconiiftent with theory. But after I
had conceived the idea of giving to this theory the extent of
which I have juft fpoken, | arrived at refults fo correét, that
Ino longer entertained any doubt of the exiftence of the
Jaws on which thefe refults depend.

Reflections on the preceding Refults.

All the metamorphofes to which cryflals are fubjected
depend on thofe laws of ftructure juft explained, and others
of the like kind. Sometimes the decrements take place at
the fame time on all the edges; as in the dodecaedron hav-
ing rhombufes for its planes, as before mentioned ; or on all
the angles, as in the o<taedron originating from a cube.
Sometimes they take place only on certain edges or certain
angles. Sometimes there is an uniformity between them, fo
that it is one fingle law by one, two, three ranges, &c. which »
aéts on the different edges, or the different angles; as is ob-
ferved in the two folids of which I fhall fpeak hereafter.
Sometimes the law varies from one edge to the other, or
from one angle to the other; and this happens above all
when the nucleus has not a fymmetrical form ; for example,
when it is a parallelopipedon, the faces of which differ by
their. refpe€tive inclinations, or by the meafure of their
angles. In certain cafes the decrements on the edges con-
cur with the decrements on the angles to produce the fame
cryftalline form.. It happens alfo fometimes that the fame

edge,

'

Theory of Cryftallifation. 292
edge, or the fame angle, is fubjected to feveral laws of de-
crement, that fucceed each other. In a word, there are cafes

- where the fecondary cryftal has faces parailel to thofe of the

primitive form, and which combine with the faces produced
by the decrements to modify the figure of the cryftal.

I call fimple fecondary forms, thofe arifing from an unique
law of decrement, the effect of which entirely conceals the
nucleus; and compound fecondary forms, thofe which arife
from feveral fimu!taneous laws of decrement, or from one
fingle law which has not attained to its extent, fo that there
remain faces parallel to thofe of the nucleus, which concur,
with the faces produced by the decrement, to diverfify the
afpect of the cryftal. I fhall foon make new applications of
theory to the compound fecondary forms, of which fynta€tic
iron ore has already prefented us an example.

If amidft this diverfity of laws, fometimes infulated, fome-
times united by combinations more or lefs complex, the

number of the ranges fubtracted were itfe! f extremely vari-

able; for example, were thefe decrements by twelve, twenty,
thirty or foity ranges, or more, as might abfolutely be poffi-
ble, the multitude of the forms which might exift in each
kind of mineral would be immenfe, and exceed what could

be imagined. But the power which effets the fubtrac-

tions feems to have a_very limited aétion. ‘Thefe fubtrac-
tions for the moft part take place by one or two ranges of
moleculz. Ihave found none which exceeded four ranges,
except in a variety of calcareous fpar, forming part of the
colleQion of C. Gillet Laumont, the ftruature of which I
have lately determined, and which depends on a decrement
by fix ranges; fo that, if there exift laws which exceed the
decrements by four ranges, there is reafon to believe that

‘they rarely take place in nature. Yet, notwithttanding thefe

narrow limits, by which the laws of cryftallifation are cir-
cumicribed, I have found, by confining myfelf to two of the
fimpleft laws, that is to: fay, thofe which produce fubtraCtions
by one or two ranges, that calcareous fpar is fufceptible

U2 of

it92 Theory of Cryftallifation.
of two thoufand and forty-four different forms: a number
which exceeds more thar fifty times that of the forms al-
ready known*, and if we admit into the combination de-
crements by three and four ranges, calculation will give
8,388,604 poflible forms in regard to the fame fubftance.
This number may be ftill very much augmented in confe-
quence of decrements either mixed or intermediary.

The ftrie remarked on the furface of a multitude of cryf-
tals afford a new proof in favour of theory, as they always
have dire€tions parallel to the projecting edges of the laminz
of fuperpofition, which mutually go beyond each other, un-
lefs they arife from fome particular want of regularity. Not
that the inequalities refulting from the decrements muft be
always fenfible, if the form of the cryftals had always that
degree of finithing of which it is fufceptible ; for, on account
of the extreme minutenefs of the moleculz, the furface would
appear of a beautiful polifh, and the ftrie would elude our
fenfes. ‘There are therefore fecondary cryftals where they are
not obferved in any manner, while they are very vifble in other
cryftals of the fame nature and form. In the latter cafe, the
action of the caufes which produce cryftallifation not having
fully enjoyed all the conditions neceflary for perfecting that
fo delicate operation of nature, there have been ftarts and
interruptions in their progrefs, fo that, the law of continuity
not having been exaétly obferved, there have remajned on the
furface of the cryftal vacancies apparent to our eyes. Ina
word, it is feen that fuch {mall deviations are attended with
this advantage, that they point out the dire€tion according
to which the ftriz are arranged in lints on the perfect forms
where they efcape our organs, and thus contribute to unfold
to us the rea] mechanifm of the ftrudture.

The {mall vacuities which the edges of the laminz of fu-

. perpofition leave on the furface of even the moft perfeé fe-

*In my Effay, p. 217 e¢ (eg. I carried the number of thefe forms only
t0 1019, becaufe J had not introduced as an element in my calcyla:ion —
modification of the law of decrements, with the exiftence of which I

net then acquainted,
7 condary

Theory of Cryftallifation. 293
éondary cryftals by their re-entering and falient angles, thus
afford a fatisfa€tory folution of the difficulty a little before
mentioned; which is, that the fragments obtained bydivifion,
the external facets of which form part of the faces of the fe-
- Condary cryftal, are not like thofé drawn from the interior
part. For this diverfity, which is only apparent, arifes from
the facets in queftion béing compofed of a multitude of
fmall planes; really inclined to one another, but which, on
account of their Tmailnefs, prefent the appearance of one
plane ; fo that, if the divifion could reach its utmoft bounds,
all thefe fragments would be refolved into molecule, fimilar
to each other,’ and to thofe fituated towards the céntre.

The fecundity of the laws on which the variations of eryf-
talline forms depend, is not confined to the producing of a
multitude of very different forms with the fame moleculz.
It often happens alfo, that molecule of different figures ar-
range themfelves in fuch a manner as to give rife to like po-
lyedra in different kinds of minerals. Thus the dodecaedron
with rhombufes for its planes, which we obtained by com-
bining cubie molecule, exifts in the granite with a ftructure
compofed of {mall tetraédra having ifofceles triangular faces,
as I fhall prove hereafter; and I have found it in {parry
fluors where there is alfo an affemblage of tetraedra, but re-
gular ; that is to fay, the faces of which are equilateral tri-
angles. Nay more: it is poffible that fimilar molecule may
produce the fame cryftalline form by different laws’ of de-
orement*. In fhort, calculation has conduéted me to ano-
ther refult, which appéared to’ me ftill more remarkable,
which is, that; in confequence of a fimple law of decrement,
there may exift a cry{tal which externally has a perfect re-
femblance to the nucleus, that is to fay, to a folid that does
hot arife from any law of decrement +.

* Mem. del Acad. an 1788, p. 17 & 26+
t Ibid. p. 23.

Ug Various

ZO. Theory of Cry/ftallifation.
~Parious Examples of compound Jecondary Forts.
-Prifmatic Calcareous Spar (Fig. 1. Plate 11.) a

Spath calcaire en prifme hexatdre. Daubenton Tab: Afiner.
edit. 1792, p- 15, n° 6. De I’lfle Cry/fallographie, tom. 3.
p- 514. var. 10.

The bafes of this prifm are produced in confequence of a
decrement by a fingle range on the angles of the fummits
baf, gaf, bag, dex, dec, cex (fig. 4-), of the primitive
form. ‘The fix planes refult from a decrement by two
ranges.on the angles bd f, fxg, beg, dfx, dbc, cg x, op-
pofite to the preceding. Let abdf (fig. 50.) be the fame
face‘of the nucleusas fiz. 4. The decreafing edges fituated
towards the angle of the fummit a will fucceffively correfpond
withthelines i, £/, &c. andthofe which took towards the infe-
rior angle d will have the pofitions pointed out by mm, op, &c.
But in confequence of the firft decrement taking place by
one ‘range, we prove that the face which refults from it is
perpendicular to the axis ; and calculation fhews, in the like
manner, that ‘the fecond decrement, which takes place by
two ranges, produces planes parallel to the axis, and thus
the’ fecondary folid is’a regular hexaedral prifm.

To difplay farther the ftruQture of this prifm let us re-
matk that, in the preduétion of any one abcnih (fig. 1-)
of the two bafes, we may confine ourfelves to confider the
effect of one only of the three decrements which take place
around the folid angle a ( fig. 4.), for example, of that which
takes place on'the angle af, fuppofing that the laminz ap-
plied onthe two other faces, fag, bagc, do not decreafe
but to affift the refult of the principal decrement, which
takes place in regard to the angle ba f. But here thefe auxi-
liary decrements are altogether fimilar to'that thé effect of
which they are fuppofed to prolong.

The cafe will be totally different if we apply the fame ob-
fervation to the decrements which are effected by two ranges
on the inferior angles bd f, dfx, fx g, &c.and which pro-

duce

°

Theory of Cryftallifation. 295
duce the fix planes of the prifm. For example, if we con-
fider the effe& of the decrement on the angle dfx, it is
neceflary alfo that the lamine applied on the faces afd by
afxg (fig. 4-)s fhould experietice towards their lateral angles
afd, afx, adjacent to the angle dfx, variations which fe-
cond the effeét of the generating decrement. But here
thefe variations are intermediary decrements by ranges of
double moleculz.

To conceive a better idea of thefe variations, let us Te-
fume the face abdf (fig. 50... The variations in queftion
will take place parallel to the lines ce, rx, g% vy, Kee
that is to fay, by one range of double molecule, and in fuch
a manner that there will always be two laminz on a level at
their edges in the dire€tion of the height. By this it is evie
dent why the lamine taken from the prifm by the firft fec-
tions are trapeziums, fuch as p/us (fig. 1.), in which the
affortment of the {mall compofing rhombufes will be the
fame as on the trapezium usop (fig. 50-). We may in the
like manner aflign the reafon of the different figures through
which the laminz, fucceflively detached, before arriving at
the nucleus, are obliged to pafs. But this detail would lead
us too far. Ina word, I mult here repeat, that every thing
is included in the effect of the principal decrements : that
is to fay, in the prefent cafe, of thofewhich take place on the
faperior and inferior angles, or parallel to the horizontal
diagonals ; and after the firft lamina of fuperpofition, the
figure of the cryftal is given according to this fingle condi-
tion, that the initial faces be prolonged fo as to interfe&
each other.

The prifm is fufceptible of varying in the length of its:
axis compared with its thicknefs, which depends on the dif-
ferent epochs at which the decrements commence, or are,
fuppofed to commence. For example: if we fuppofe that
the decrement, which takes place towards the inferior angles
aéts alone at firft on a certain number of laminz, the axis
of the cryftal will be fo much the longer as the commence-
oe U4 ment

296 Theory of Cryftallifation.

ment of the decrement on the fuperior angles fhall have beew’
retarded. ‘This difference of epochs becomes fenfible by in=
fpedting the dodecaedron, fig. 2, which is one of the refults
of the mechanical divifion of the prifm. Itis there feen that
the pentagonal lamin# of the fummits, fuch zs AOIR S;
decreafe only by their edge RS, which correfponds to the
inferior angle 6df (jig. 4.), while, by their upper parts, they
continue to envelop the cryftal without experiencing any
decrement towards that fide; fo that it is only on the la-
mine moft diftant from the axis,. as that correfponding to
psu«l, that the two decrements take place at the fame time.

The refult which we have explained is general; that is to
fay, that, whatever may be the angles of the primitive rhom-
boid, the fecondary folid will always be a regular hexaedral
priim.

Amphitrigonous Eron Ore,

(Fig. §1 reprefents this cryftal in a horizontal projection,
and fig. 52 in perfpedtive.)

Mine de fer a 24 faces. Daubenton Tab. Miner. edit. 17925
p- 30, n° 2. De I'lfle Cry/tallographie, tom. iii. p. 193 et
fuiv. var. 5, 6,7.

Geomet. chara&. Refpe€tive inclination of the triangles
gen, gcd, &c. from the fame fummit 146° 26! 33"; of the
lateral triangles dg 1, 6 gq, to the adjacent pentagons, fuch
as gutmn, 154° 45' 39”.

This form is that under which the iron ore of the ifland
of Elba moft commonly appears. It refults from a decre-
ment by two ranges on the angles c, # (fig. 46.), to the funi-

mits of a cubic nucleus which produces the ifofceles trian-

gies gen, gcd, ned (fig. 51 and §2), and of a fecond de-
crement by three ranges on the lateral angles chp, er py:

ers, &c. which produce the triangles mar, rank, ug dy

qg4, &c. Thefe two decrements ftop at a certain term,
fo that there remain faces parallel to thofe of the nucleus,
viz. the pentagons gutmn, hdukl, &c. (fig. 51+)

The

“Zan

Theory of Cryfullifation. 207
“The fitft decrement is the fame as that which produces the
thomboidal iron ore already mentioned. The fecond has
this property, that, if its effe€ were complete, it would give
a dodecaedton of ifofceles triangles, or compofed of two
right pyramids united at their bafes. In the cafe of any
other decrement by two, four or more ranges, the faces of
the dodecaedron would be fcalene triangles.
The triangles of the fummits are frequently furrowed by
firiz, parallel to the bafes gx, dn, gd, of thefe triangles,
and which point out the direCtion of the decrement.

Analogical Calcareous Spar (Fig. 53 )+

De V'Ifle Cryflallographie, tom. i. p- 543, pl. 4, fig. 36.

Gecmet. charaét. Inclination of any one, 7 me 4, of the tra«
pezoids of the’ fummits to the corre/ponding vertical trape-
zoid ecpg ¥:6° 33’ 54’; angles of the fame trapezoid,
2 = t¥4g° 18! 66%; ¢ = 75°31! 20s mor b = 85° 4! sail.
Angles of the trapezoid eho g, ¢ = 90°53 0 = 127° 25! §3!"5
£ = 67° 47! 44”; b = 74° 46! 23/5 of the trapezoid ceg py
f= 00° 3.9 =08°.22" 4675 core = 100953" 97",

Geomet. propert. 1. In each vertical ¢rapezoid the triangle
ceg is equilateral. 2. The height ex of this triangle is

double the height pv of the oppofite triangle cpg. 3. In -

the trapezoid e4og and the others fimilarly fituated the
angle Aegis aright angle. 4. If the diagonal g h be drawn,
the triangle 4 eg will be fimilar to any one aof (fig. 4.) of
thofe which would be produced by drawing, in the primitive
thombus, the two diagonals 4f, ad. 5. If in the trapezoid
#mih, or any other fituated at the fammits, the diagonals e7,
mh, be drawn, the height ¢/ of the inferior triangle meh
will be double the height 7/ of the fuperior triangle mih
6. The triangle mi is fimilar to a half of the rhombus of
very obtufe fpar, divided by the horizontal diagonal; and
the triangle m¢h is fimilar to a half of the rhombus of the
acute {par, divided in the fame manner.

The

298 Theory of Eryfallifation.

The numerous analogies by which this variety is coms
neéted with different cry{talline forms, whether we confider
certain angles formed by planes, as the angle heg of gos
the angle ¢eg of 60°, or certain triangles obtained by draw-

ing the diagonals of the trapezoids, have induced me to give.

it the name of analogical par. It is derived from three other
varieties mentioned before, viz. very obtufe {par by the tra-
pezoids emih, fiht, &c.; metaftatic fpar by the trape-
zoids emdc, ehog, ohtz, &c. and the prifmatic fpar :by
the trapezoids bdck, cegp, &c. which are confequently
parallel to the axis.

It often happens that the trapezoids imeh, fibt, &c.
are feparated, by an intermediary ridge, from the vertical
trapezoids cegp, gozr, &c. In that cafe the trapezoids
cdme,gehe, &c. are changed into pentagons. I have here
fuppofed the cryftal brought back to the moft fymmetric
figure, that is to fay, having its furface compofed only of

quadrilaterals, as fometimes happens. ‘This variety is found

in Derbythire.

Icofaedral Sulfuie of Iron (Fig. §5.)-

Pyrite ferrugineufe polyedre & vingt faces triangulaires.
Daubenton Zab. Miner. edit. 1792, p. 30. De I'fle Cry
tallographie, tom. lil. p. 2325 Var. 22.

Geomet. charac. Refpective inclinations of the ifofceles
triangles PLR, PSR, 126° 52’ 11”; of any one P NL of
the equilateral triangles, to each adjacent ifofceles triangle
PLR or LNK 140° 46/17". Angles of the ifofceles tri-
angle P_L.R, .L =)48°, 11’ 20” 5 .P.or R =/65° 54" 20%.

This variety refults from a combination of the law which
produces the oftaedron originating from a cube (jig. 42-),
with that which takes place for the dodecaedron with pen-
tagonal planes (jg. 19 and 20). The firft law gives birth
to the eight equilateral triangles which correfpond with the
folid angles of the nucleus, and the fecond to twelve ifofceles

triangles,

Be ie

Theory of Cryfial.ifatior. 299
triangles, fituated, two and two, above the fix faces of the
fame nucleus. If we had a dodecaedron fimilar to that of
jig. 20, and wifhed to convert it geometrically into an ico~
faedron, fuch as that in queftion, it would be fufhctent to

make the planes of eight feCtions pafs through it in the fol-
lowing manner, viz. one through the three angles P, N, L,
(fig. 19.), another through the angles P,M,S, a third ©
through the angles L,R,U, &c. A comparifon of the figures’
1g and 55 will fhew, by the correfpondence of the letters,
the relation between the two polyedra; but this is an ope-
ration merely technical, to which nature could not defcend.

I fhall obferve, befides, that the nucleus of the icofaedron,
to which we fhould arrive, would be much fmaller than that
of the dodecaedron, fince'the folid angles of the latter nu-
cleus would be confounded with the angles D, C,G, &e.
(fig. 20.) of the dodecaedron; whereas the other nucleus
would have its folid angles fituated in the middle of .the
equilateral triangles MP5, NPL, URL, Xe. (fg. 55.).

The icofaedron of the fulphure, of iron has been con-
founded with the regular icofaedron of geometry, which
differs from it very fenfibly, fince all its triangles are equi-
lateral. It is demonftrated by theory, that the exiftence of
the latter icofaedron is as impoffible in mineralogy as that of -
the dodecaedron; fo that among the five regular polyedra of
geometry, viz. the cube, the tetraedron, the o€taedron, the
dodecaedron, and the icofaedron, the three former only can -
exift there, in confequence of the laws of cryftallifation. It
is not uncommon therefore to find them among cryftals of
various kinds of minerals.
The icofaedron of the fulphure of iron is much lefs coms

mon than the dodecaedron. It is found in folitary cryftals.

Ihave one which is complete, and about half an inch in
thicknefs.

Polyn omous

“400 Theory of Cryfallifation.

Polynomous Petunzé (Fig. 56) *.

Spath étincelant ou feld-[path en prifine & dix pans avec def
fommets & deux faces et quatre facettes. Daubenton Tab.
Miner. edit. 1792, p- 4, var. 2.

Geomet chara. Refpective inclination of the narrow
planes on km, cfhg, to the adjacent planes on each fide
150°; of the planes ct g, PomN to thofe contiguous
to them by the edges ¢F, PN 120°; of the heptagon’
pGcldez to the enneagon BzebnoP#s, 99° 41’ 85
ef the trapezium dafe¢ both to the plané aba fhilk and
to the heptagon pGredez, 135°; of the facet déab or
AB zp to the fame heptagon, 124° 15! 15’.

Ehave not yet obferved the petunzé naturally cryftallifed
under its primitive form. ‘This form, fuch as it is given by’
the mechanical divifion of fecondary cryftals, is that of am’
oblique prifm of four planes (fg. 58), two of which, fuch as’
GOAD, RBHN, are perpendicular to the bafes ADNHE;’
OGREB. The other two, viz. BOAH, RGDN, make,’
with the former, angles of 120° at the ridges O A, RN, and
angles of 60° towards the oppofite ridges BH, GD. ‘Thefe
planes are inclined to the bafes at the place of the ridges’
GO, BR, 111° 29! 43”, and at the oppofite ridges 68° 30°
ig!

This form is at the fame time that of the molecule.
Theory fhews that the two parallelograms GOAD, OGRB,
. as well as their parallels, are equal in extent; and that the
parallelogram BO A H, or its oppofite, RGDN, is double
each of the preceding; which may ferve to explain the
roughnefs of the fections made.in the direction B OAH,
when compared with thofe obtained in the directions of the

* I have adopted the name petunzé, which is that given to this fub-
{tance in China, where it is employed in making porcelain. The word
fpar (/patb) has become fo vague, by the application of it to fubftances
very different in their nature, that it is much to be wifhed that it were:
banifhed from the nomenclature of minerals,

- {mali

Theory of Cryftallifation. R08
Amall parallelograms, and which are always extremely fmooth
and brilliant. Moreover, if the diagonal OR be drawn, it
will be found perpendicular to OA and RN); or, what
amounts to the fame, will be fituated horizontally, by fup-.
pofing that the ridges OA, BH, &c. have a vertical
pofition. We fhall foon have occafion to make ufe of this
obfervation. :

The polynomous petunzé prefents the moft complicated
variety which I have obferyed among cryftals of this kind.
To form an idea of its ftru€ture, let us fuppofe that pyr
(fg. 57) reprefents a fection of the nucleus AR ( fg. 58)
made by a plane perpendicylar to the parallelograms
GOAD, BOAH, and fubdivided into a multitude of {mall
parallelograms, which are the analogous fections of fo many »
molecule. Here the fide yr (jg. 57) which is the fame
fe€tion of the cutting plane as GOAD), is greater than it
ought to be in regard to the fide er (fig. 57), which is the
fame fection as BOAH (fig. 58): but thefe dimenfions
are fuited to thofe of the fecondary cryftal, and here occafion
no difficulty, becaufe we may fuppofe that the primitive
form has been extended more in one dire€tion than in
another ; for this form, as | have already remarked, is only
a convenient datum for the explanation of the ftru€ture, and
the cryftal confifts merely in an affemblage of fimilar mole-
cul ; fo that itis the dimenfions of thefe molecule which
remain invariable.

This being premifed, we fhall find, by comparing the
figures 56 and 57; 1ft, that the plane fabnklih (fig. 56)
and its oppofite, which correfpond to ma, dg, ( fig. 57), are
parallel to two of the planes of the nucleus, viz. GOAD,
BRNH ( fg. 58), and confequently do not refult from any
Jaw of decrement; 2d, that the plane PomN, and its op-
pofite (jig. 56), which correfpond to ao, eg (fig. 57)) are
alfo parallel to two of the planes of the nucleus, viz.
BOAH, RGDN (fg. 58); 3d, that the plane onkm
and its oppofite (fig. 56), which correfpond to 0%) €

fg

502 Theory of Cryftallifation.
(fig. 57) vefult from a decrement by two ranges parallel'te
the ridges AO, NR (jig. 58); 4th, that the plane cfgh
and its oppofite (fig. 56), which correfpond to my, dc
(fig. 57); refult from a decrement by four ranges parallel to
the ridges GD BH (jig. 58); 5th, that the plane c7*7F ge
and its oppofite (jig. 56), which corrtfpond to fy, ca

(fig. $7), vefalt from a decrement by two ranges parallel to
the fame ridges G D, BH (fg. 58), which decrement takes
place on the other fide of thefe ridges. It may be feen by
what has been already faid, that decrements different in their
meafute give rife to planes fimilarly fituated, fuch as on km
and cfg bh ( fig. 56), which is a confequence of the particular
figure of the molecule. '

With regard to the faces of the fummit, the heptagon
pGtcdez_(fig. 56) is fituated parallel to the bafe BRGO
(fie. 58). The enneagon BsrPonbez (fig. 56) is pro-
duced in confequence of a decrement by one range on the
angle OBR (jg. 58), or parallel to the diagonal OR;
which decrement does not attain to its full extent, and leaves
fubfitting the neighbouring heptagon parallel to the bafe
BRGO. It may be readily conceived, after what has been
faid on the pofition of the diagonal OR, why the line ez
( fig. 56), which feparates the two large faces of the fummit,
is fituated horizontally, fuppofing that the planes have a
vertical pofition.

The trapeziums dafc, Ap GC, refult from a decrement
by one range on the ridges GO, BR, (fig. 58). The
facet deba ( fig 56) arifes from a decrement by two ranges,
parallel to the ridge BO (fig. 58). With régard to the
other facet AB z p, which has the fame pofition as the pre-
ceding, in regard to the oppofite part of the cryftal, it refults
from an intermediary law by a range of double moleculz on

the angle OBR (jig. 58). The rhombufes bclh, kl fu.

(jig. §9), reprefent the horizontal feétions of two of thefe
double, molecule, taken in the fame range, and whofe rela-

tion to the reft of the affortment will become fenfible by .

comparing

Lawvifi es Abparatis for producing Water. 363
comparing the rhombufes ih queition with thofe marked te
the fame letters (fig. 57).

The cryltals ot chis variety are fubje& to a change of
dimenfions, which is, that the faces pGtcdez, fabnklih, and
their oppofites; which are at right angles to each other, aré

ftretched out, in the dire€tion of their breadth, in fuch a

manner that they exhibit the appeatance of a quadrilateral
rectangular piifm, the fummits of which would be formed
by the faces fituated towards the ridges PN, Fa.

This variety is found in opake cryftals, and of a whitithy
yellowith, and fometimes reddifh colour, in the granités of
Auvergne, and of different countries. There are fome of
them in groups and fome fingle, but the latter are unicom=

mon.
[To be concluded in the next Number.]

XII. Dejcription of the Apparatus employed by LAVOISIER
to produce Water from its component Parts, Oxygen and
Hydrogen.

Tue difcovery made by Mr. Cavendith of the compofi-
tion of water having effeCted a complete revolution in the
theory of chemiftry, it will no doubt gratify many of our
readers to fee fome account of the principal apparatufes
which have been contrived to exhibit this phenomenon.

Fig. 1, Plate X. is that ufed by Mr. Lavoifier. A is a

balloon holding about 30 pints, having a large opening, to

which is cemented the plate of copper B pierced with four
holes, in which four tubes terminate. The firft tube HA is
intended to be adapted to an air-pump, by which the balloon
may be exhaufted of its air. The fecond tube gg communi-
cates by its extremity MM with a refervoir of oxygen: gas,
from which the balloon is to be filled. ‘The third tube dDd
communicates by its extremity dNN with a refervoir of
hydrogen gas. ‘Ihe extremity d of this tube terminates in a
capillary opening, through which the hydrogen gas contained

: 12

404 Lavoifier’s Apparatus for producing Water.
in the refervoir is forced, with a moderate degree of quicke
nefs, by the preflure of a column of one or two inches of
water. The fourth tube, GL, contains.a metallic wire,
having a knob at its extremity L, intended for tran{mitting
an electrical {park from L to d, on purpote to fet fire to the
hydrogew gas: this wire is moveable in the tube, that the
Operator may be able to move the knob L to or from the ex-
tremity d of the tube Dd.

The three tubes dDd, gg, and H4, are all provided with
ftop cocks.

That the hydrogen gas and oxygen gas may be as much.

as poflible deprived of water, they are made to pafs, in their
way to the ba!loon A, through the tubes MM, NN, of
about an inch diameter; and thefe are filled with falts, which,
from their deliquefcent nature, greedily attract the moifture
of the gas: fuch are the acetite of potafh, and the muriat or
nitrat of lime. ‘Thefe falts muft only be reduced to a coarfe
powder, that they may not run into lumps, and prevent the
gafes from pafling through their interftices.

Being provided with a fufficient quantity of the oxygen
and hydrogen gafes (the latter in the proportion of 2 to I
of the former), and having adjufted every thing*properly, as
above direfted, the tube H4 muft be adapted to an air-
pump, and the balloon A exhaufied of its air. Next admit
the oxygen fo as to fill the balioon, and then by means of
preflure force a flream of hydrogen through the tube D d, to
which fet fire by an eleétrical fpark fent down the wire con-
tained in the tube GL. Fy means of the above defcribed ap-
paratus the mutual combuttion of thefe two gafes may be con;
tinved for a long time, as the operator has the power of fup-
plving them to the balloon from their refervoirs, in proportion
as they are confumed *. It appears from the moft accurate
experiments, that roo parts of water contain 85 parts of oxye
genand 15 of hydrogen by weignt.

* In a future number we fhall give a plate of the apparatus contrived by

Dr. Higgins for the fame purpole.
ie ts ess KUL. Den

[ 305 J
XIII. Defeription of the Apparatus contrived by'Mr. Carazto

for containing Gas of any Kind, and transferring it to Bottles,
Bladders, €5'c.

Fr G. 6, Plate X, fhews a fection of the veffel A, which
may be of glafs or tin; B, a funnel, into which is faftened a
bent glafs tube C; D, is a tube foldered to the funnel, and
which with it pafles through the cork a; E, reprefents a
tube of tin, wood, or other materials, to one end of which a
bladder or oiled filk bag is faftened; the other is inferted in
the tube D.

The veffel A being filled with the required gas*, when-
ever it may be neceflary to transfer any quantity to a bottle,
bladder, &c. an equal quantity of water is to be poured
through the funnel B, which will difplace the gas, and force
it through D into E.

The bent part of the tube C, by always. containing fome
water, prevents the gas from efcaping through the funnel ;
but when the apparatus is to be fet by, both the funnel, and
the tube D, muft be clofe ftopped with corks.

XIV. Curfory View of fome of the late Difcoveries in Science.
[Continued from the laft Number, p. 212.]
SENSIBILITY OF PLANTS.

Tu E caufe of this fenfibility is ftill little known. The
following is the explanation given of it by Lamark*:
‘In my opinion, there exift in the articulations of many

* This is done by taking out the cork with the funnel, &c. filling the

- veffel with water, and inverting it with its opening under water. Thus, if

a tube leading from the apparatus whence the gas is produced, /be brought

under the mouth of the veffel, the gas will afcend and difplace the water
rill it be full.

+ Memoives de Phyfique, p. 288.
VoL. J. Ce plants,

306i Curfory View of

plants, and in. certain parts of them, particular veficles
which, efpecially in warm weather, become filled with
elaftic and very fubtle excretory vapours. Thefe vapours,
which are accumulated and retained to a certain degree in
the veficles, fwell them out, and make them produce an ex-
tenfion in all the moveable parts where they are fituated ;
but on the leaft fhock or agitation the elaftic and fubtle va-
pours which fill thefe veficles efcape, and are exhaled into -
the atmofphere.. The veficles being then emptied fhrink ;
and the vegetable part, which is not preferved in its ex~
tended ftate, fhrinks alfo, and falls back into the articulation
where the veficle was placed. Soon after the veficle be-
comes filled again, though in an infenfible manner, and ftill
produces an extenfion of the leaf-ftalk or petiole, which 2
caufe like the former may deftroy.

“In the hedyfarum gyrans, the veficles of the bottom of
the {mall leaves being filled to a certain degree, then empty
themfelves infenfibly, become filled again as before, and re-
empty themfelves in the like manner, without any other de-
termining caufe than the effect of their plenitude. But this
continued alternation of repletion and evacuation keeps in
conftant movement the fmall leaves of the plant, which, when
the weather is warm, rife and fall alternately, but in a flow —
manner.”

Shade, or the abfence of light, by the coolnefs refulting
from it, caufes that evacuation or fhrinking of the veficles
juft mentioned. Hence the clofing up in the evening of
certain parts of plants, efpecially of the leguminous families,
to which botanifts have given the name of their fleep.

It is by thefe caufes, or others analogous, that-all the move~
ments of thefe plants ought to be explained. A great num-
ber of plants experience particular movements in the fexual
parts at the time of their fecundation. Thefe movements

muft be produced by the aura /eminalis *.
IRRIT A=
* It may not, perhaps, be improper to take notice here of the following
cuious ciscumftance refpeéting a conferva never before found in France,
f and

Jome of the late Difcoveries in Science. 307

IRRITABILITY OF THE ANIMAL FIBRE. -

Notwith(tanding the many refearches made refpeéting
the caufe of this irritability, much is ftill wanting. Girtan-
ner afcribes it chiefly to oxygen: but the proofs which he
gives in {upport of his opinion do not appear fatisfaétory 5
fince the air does not feem to haye a dire& influence on
the irritability of the heart. For example, if the vein of an
animal be opened, and if a bubble of vital air or oxygen gas
an be introduced into it, by means of a fmall tube, as foon
as the air reaches the heart the animal fends forth a cry of
pain and expires. Bichet, who made this experiment *, re-
peated it with atmofpheric air, azot, hydrogen, and the car-
bonic acid gas; and the animal perifhed in the like manner ;
but cold water injected into a vein does not produce the
likeveffe&t. Bichet concludes, that the death of the animal
is occafioned by the interception of the air between-the co-
lumns of the arterial and venal blood. But, in this cafe, we
may reft aflured that oxygen gas deftroys the animal.

Dr. Menzies obferved, that the irritability of the heart pre-
ferved itfelf longer in animals ftrangled or drowned than in
thofe which perifhed in gas. He thence concludes, that the
particular ftate which the blood acquires in pafling through

the lungs, and which gives it thofe fenfible qualities that

and the fame reprefented by Muller in his Flora Danica, under the name
of conferva jugalis, which was communicated, not long ago, to the Philo«
matic Society at Paris. Citizens Charles and Romain Coquebert having
colleéted fome of this conferva, in the neighbourhood of Paris, afcertained
by means of an excellent microfcopes conftruéted by Nairne and Blunt,
that in this f{pecies there are male and female filaments, which unite by
an aétual copulation ; that certain globules contained in the male filaments
pafs into the interior part of the female filaments; and that by this union
there are formed in the latter feeds, or, if we may ufe the expreffion, final
gva, which reproduce the fpecies. Fhis is the firft inftance in the ye-
getable kingdom of a reproduétion abfolutely analogous to that which we’
Sind among animals. Epir.

* Société Philom. page 18, EE
X 2 diftinguith

308. Late Difcoveries in Science.

diftinguifh the arterial from the venal blood, is not the real
caufe which gives play to the. irritability of the heart, but
that its a€tion is particularly owing to the effect of heat com-
bined with humidity.

Van Marum, Hildebrant, and other philofophers think
that there is a real irritability in plants, and particularly in
thofe which have fpontaneous kinds of movement. It has
thence been afferted, that oxygen has the fame effet upon
thofe plants called fenfitive, fuch as the humble plant (mi-
mofa pudica), the hedyfarum gyrans, &c, as upon animals.

Pefchier has made feveral experiments to afcertain whe=
ther this opinion was well founded; but oxygen never ap-
peared to him to produce any effect upon thefe plants. He
afterwards examined whether thefe movements of thofe
plants called fenfitive are owing to real irritability, like that
of animals. The numerous experiments which he made
on this fubjeé& gave him reafon to conclude, that mo real
irritability could be afcribed to thefe plants, and that. all the
movements they experience, by the fimple touch or other-
wife, are merely mechanical; and indeed plants have nei-
ther nerves nor mufcles, nor any organs analogous to thofe
which, in animals, appear to be the feat of irritability. ©

This difference in the organization of animals and vege-
tables cannot be denied ; but on the other hand it is equally
certain, that what is called irritability in animals is owing to
mechanical caufes. “The movement of the mufcular fibre in
animals is altogether as mechanical as the fhrinking of a
{prig of the fenfitive plant when it is touched. That of the
mufcular fibre is owing to an efflux of the nervous fluid;
that of the fenfitive to the efflux of another fluid, which is as
little known. But it may here perhaps be faid, The animal
fibre, fuch as the heart, is ftill irritable a long time after it
has been feparated from the reft of the body, which is not
the cafe with the vegetable fibre. This is true: but it does
not prove that it is not always a mechanical caufe which’
acts in ee circumftances ; its a¢tion only is of longer

duration 5

On. Germination. 309

duration; for, in whatever manner the aétion of this muf-
cular fibre be confidered, it cannot be moved but by phyfical
caufes. The queftion then will be, to difcover what are
thefe phyfical caufes.

It appears very certain that the caufe of mufcular move-
ment is owing to the nerves, fince a part in which the .
nerves are palfied, or confined by a ligature, has no longer
any movement. But how does the nerve move? Some :
philofophers have compared its movement to the ofcillations ©
of an extended cord which is flruck: But, 1. The nerves =
are not extended: 2. They are envelcped on all fides ; where-
as the cord has no points of contact but at its two extre-
mities.

It appears more probable to others to confider the nerve
as one or more veffels conftruéted almoft like the lymphatic
veflels ; that is to fay, compofed of a feries of veficles in
which flows a fluid called the nervous fluid. I have fup-
pofed that this nervous fluid is of a nature analogous to
that of the aura feminalis. Others have fought for the caufe
of irritability in ele€tricity, and the experiments on Galva-
nifm feem to give fome weight to this opinion,

[Lo be continued. }

XV. On the Effects of Oxygen in accelerating Germination,
From the Journal de Phyfique, 1798.

R. Humsorpr difcovered, in 1793, that fmple metallic
fubftances are unfavourable to the germination of plants,
and that metallic oxydes favour it in proportion to their
degree of oxydation. This difcovery induced him to fearch
for a fubftance with which oxygen might be fo weakly com-
bined as to be eafily feparated, and he made choice of oxy-
genated muriatic acid gas mixed with water. Crefles (/epi-
dium fativum) in the oxygenated muriatic acid fhewed germs
at the end of fix hours, and in common water at the end

X 3 of

36 : On the Effedts of Oxygen

of 32 hours. The action of the firft fluid on the wepiliide
fibres is announced by an enormous quantity of air bubbles
' which cover the feeds, a phenomenon not exhibited by
water till at the end of from 30 to 45 minutes. Thefe
experiments announced in Humboldt’s Flora Subterranea

Fribergenfis, and in his Aphorifms on the chemical phyfiology —

of Plants, have been repeated by others *. They were made
at a temperature of from 12-to 15 Reaumur. In the fum-
mer of 1796, Humboldt began a new feries of experiments,
and found that by joining the ftimulus of caloric to that of
oxygen he was enabled ftill more to accelerate the progrefs
of vegetation. He took the feeds of garden crefles (lepidium
fativum), peas (pi/um “fativum), French beans (phajeolus vul-
garis), garden lettuce (/aduca fativa), mignonette (refeda
odorata), equal quantities of which were thrown into pure
water and the oxygenated muriatic acid at a temperature of
88° F. Creffes exhibited germs in three hours in the oxygen-
ated muriatic acid, while none were feen in water till the
end of 26 hours. In the muriatic, nitric + or fulphuric
- acid, pure or mixed with water, there was no germ at all:
the oxygen feemed there to be too intimately united with
bafes of azot or fulphur, to be difengaged by the affinities
prefented by the fibres of the vegetable. The author an-
nounces that his difcoveries may one day be of great benefit
in the cultivation of plants. His experiments have been
repeated with great induftry and zeal by feveral diftinguifhed

* See Uflar’s Fragments of Phythology, Plenck’s Phyfiology, Villde~
now’s Dendrology, and Dictionnaire de Phy/fique par Gehler. Gr

+ The nitric acid, however, diluted with a great deal of water, accele-
" rates germination alfo, according to the experiments of Candolle, a young
natural'ft, who has applied with great faccefs to vegetable phyfiology.
This phenomenon is the more interefting, as chemiftry aflords other ana-
logies of the oxygenated muriatic acid and the nitric acid. Profeffor
Pfafs, at Kiel, by purfuing Humboldt’s experiments, has found that frogs

fuffocated in oxygenated muriatic acid gas increafe in irritability, while thofe ©

which perifh in carbonic acid gas are lefs fenfible of Galvanifm..

philos

a

in accelerating Germination. 31

philofophers. Profeffor Pohl : ae caufed to germinate

in oxygenated muriatic acid the feed of a new kind of eu-

phorbia taken from Bocconi’s collection of dried plants,

110 or 120 years old. Jacquin and Vander Schott at
Vienna threw into oxygenated muriatic acid all the old

‘feeds which had been kept 20 or 30 years at the botanical

garden, every attempt to produce vegetation in which had
been fruitlefs, and the greater part of them were ftimulated
with fuccefs. Even the hardeft feeds yielded to this agent.
Among thofe which germinated were the yellow bonduc or
nickar tree (guilandina bonduc), the pigeon cytifus or pigeon
pea (cytifus cajan), the dedonaa anguftifolia, the climbing mi-
mofa (mimofa feandens), and new kinds of the homea.—
There are now fhewn at Vienna very valuable plants which

‘are entirely owing to the oxygenated muriatic acid, and

which are at prefent from five to eight inches in height.
Humboldt caufed to germinate the c/ufia rofea, the feeds of
which had been brought from the Bahama iflands by Boofe,

_ and which before had refifted every effort to make them

vegetate. For this purpofe he employed a new procefs,
which feems likely to be much eafier for gardeners who
have not an opportunity of procuring the oxygenated mu-
riatic acid; He formed a pafte by mixing the feeds with the
black oxyde of manganefe, and then poured over it the mu-
riatic acid diluted with water. Three cubic inches of water
were mixed with half a cubic inch of the muriatic acid. J he
yeflel which contains this mixture muft be covered, but not
clofely fhut ; elfe it might readily burft. At the tempera-
ture of 95° the muriatic acid becomes ftrongly oxydated ;
the oxygenated muriatic gas which is difengaged pafles
through the feeds; and it is during this paflage that irritation
of the vegetable fibres takes place.

74 XVI. On

E372) .3

XVI. On the Invention of the Te elegraph, with a Dagestan f
that propofed by Dr. HOOKE.

Tue idea of conveying intelligence by means of fignals,
both during the day and in the night-time, is of very great
antiquity, as appears by the teftimony of feveral ancient
authors ; and there is reafon to believe that fome fort of tele-
graph was in ufe even among the Greeks. The deftruction of
Troy was certainly known in Greece very foon after it took
place, and before any perfon had returned fromit. A Greek
play begins with a fcene, in which a watchman defcends
from the top of a’tower in Greece, and gives information
that Troy is taken: “I have been looking out thefe ten
years,” fays he, ‘* to fee when that would happen, and this
night it has been done.” A night telegraph is alfo exprefsly
mentioned by Polybius *, who in his tenth book gives a very
circumftantial account in what manner the letters of the
alphabet may be expreffed by means of torches.

It does not appear, however, that this or any other method
of thé ancients was ever brought into general ufe, or that
any of the moderns had thought of fuch a machine as the
telegraph till the year 1663, when the Marquis of Worcefter
in his Century of Inventions affirmed, that ‘ he had dif-
covered a method by which, at a window, as far as the eye
can difcover black and white, a man might hold difcourfe
with his correfpondent without noife made, or notice taken;
being according to occafion given or means afforded, ex re
nata, and no need of provifion before hand, though much
better if forefeen, and courfe taken by mutual confent of
parties.” ‘This could be effected only by a telegraph, which
in the next fentence is declared to have been rendered fo
perfect, that by means of it the correfpondence could be
carried on “ by night as well « as by day, though as dark as
pitch is black.”

* Lib, x. cap. 40.
Forty

On the Invention of the Telegraph. 313

Forty years after, M. Amontons, an ingenious French
mechanic, born at Paris in 1663, and who died in 1705 at
the age of 42, propofed the following method: ‘ Let there
be people placed in feveral ftations, at fuch a diftance from
one another, that by the help of a telefcope a man in one
ftation may fee a fignal made in the next before him: he
muft immediately make the fame fignal, that it may be feen
by perfons in the ftation next after him, who are to commu-

nicate it to thofe in the following ftation, and fo on. Thefe

derftood only by the two perfons who are in the diftant —

fignals may be as letters of the alphabet, or as a cypher, un-.

places, and not by thofe who make the fignals. The perfon
in the fecond ftation making the fignal to the perfon in the
third, the very moment he fees it in the firft, the news may
be carrfed to the greateft diftance in as little time as is ne-
ceflary to make the fignals in the firft tation. The diftance
of the feveral ftations, which mutft be as few as poflible, is
meafured by the reach of a telefcope.”” ~Amontons tried this
method on a {mall tract of land, before feveral perfons of the
higheft rank at the court of France.

Whether the telegraph be a French invention, as that nation
afferts *, or whether Amontons’ plan for conveying intelli-
gence was founded on the hint thrown out by the Marquis of
Worcefter, we fhall not here examine; but it is certain that

the idea of a telegraph, upon a fimilar conftruction to thofe
ufed at prefent, was fuggefted by Dr. Hook towards the end

* In Rapport general des Travaux de la Societé Philematique, p. 35, the
author, fpeaking of the papers read before the fociety, fays: <* Citizen
Chappe has at different times given you an account of his experiments,
and of the refult of thofe labours by which he has been able to bring the
telegraph to its prefent degree of perfection. At firft his difcoveries were
doubted, and foon after they were carried into execution it was pretended
that traces of this invention were to be found in the works of feveral
ancient authors. Experience, however, has already done juftice in regard
to the firft affertion ; time will do the fame in regard to the fecond; and
the glory of this invention will remain to its author, and to the nation to
which be has had the honour of prefenting it.” £

0

mie
ae

314 On the Invention of the Telegraph.

of the laft century, and that he gave the firft complete de-
{cription of fuch a machine, as appears by the following exe
tract from a paper of his, read before the Royal Society on
the 21ft of May 1684*. “I propofed (fays he) fome years
fince, a method of difcourfing at a diftance, not by found,
but by fight. I fay that it is poflible to convey intelligence
from any one high and eminent place to any other that lies
within fight of it, though 3c or 40 miles diftant, in as fhort
| time almoft, as a man can write what he would have fent;
and as fuddenly to receive an anfwer as he that receives it
hath a mind to return it, or can write it.down on paper.
Nay, by the help of 3, 4, or more of fuch eminent places,
vifible to each other, lying next in a ftraight-line, ’tis poffible
to convey intelligence almoft ina moment, to twice, thrice,
or more times that diftance, with as is a certainty as by
writing.

“* For the performance of this, we muft be beholden to a
Jate invention, which we do not find any of the ancients
knew; that is, the eye muft be affilted with telefcopes, that
whatever characters are expofed at one fta‘ion, may be made
plain and diftinguifhable at the other.

* ft, For the flations: if they be far diftant, it will be ne-
ceffary that they fhould be high, and lie expofed to the fky,
that there be .no higher hill, or part of the earth beyond
them, that may hinder the diftin€tnefs of the characters,
which are to appear dark, the fky beyond them appearing
white. By which means, alfo, the vapours near the ground
will be paffed over and avoided.

“ Next, in chufing of thefe flations, care muft be taken, as
near as may be, that there be no hiJl that interpofes between
them, that is almoft high enough to touch the vifible ray,
becanfe, in fuch cafes, the refra€tion of the air of that hill
will be very apt to difturb the clear appearance of the object.

+ The whole paper may be feen in “ Philofophical Experiments and-
Obfervations of the late eminent Dr. Robert Hooke,” publifhed by Mr,
Derham. London, 1726,
| « The

On the Invention of the Telegraph. ae ae

&€ The ftations being found convenient, the next thing to
de confidered, is, what telefcopes will be neceflary for each
ftation. One of thefe telefcopes muft be fixed at each ex-
treme ftation, and two of them in each intermediate ; fo that
a man, for each glafs, fitting and looking through them, may
plainly difcover what is done in the next adjoining ftation 5
and with his pen write down on paper the characters there
expofed, in their due order; fo that there ought to be two
perfons at each extreme {tation, and three at each interme-
diate ; that, at the fame time, intelligence may be conveyed
forwards and backwards.

“ Next, there muft be certain times agreed on, when the
correfpondents are to expet; or elfe there muft be fet at
the top of the pole, in the morning, the hour appointed by
- either of the correfpondents for a¢ting that day.

“< Next, there muft be a convenient apparatus of charaCters,
at leaft, as many diftin@ charaters as there are neceflary
letters in the alphabet made ufe of, (as is exprefled in Plate X.
fig. 5.) And thofe muft be either day chara€ters, or night
chara<ters :aif they are to be made ufe of in the day time,
they may all be made of deals, and of bignefs convenient
for-the feveral diftances. Any one of which characters may
fignify any one letter of the alphabet, and the whole alphabet
may be varied 10,000 ways; fo that none hut the two ex-
treme correfpondents fhall be able to difcover the informa-
tion conveyed. If the chara¢ters are for the night, then they
may be made with links or other lights, difpofed in a certain
order, which may be covered and uncovered according to
the method agreed on. There will be alfo requifite feveral
other characters, which may, for expedition, exprefs a whole
fentence; fuch as, ‘I am ready to communicate,’ ‘lam
ready to obferve,’ &c.

**T could inftance a hundred ways of facilitating the method
of performing this defign with the more dexterity and quick-
nefs, and with little charge ; but that, I think, will be need-
lefs at prefent, fince, whenfoever fuch a way of correfpondence

fhal}

316 On the Invention of the Telegraph.

fhall be put into praétice, thofe, and many more than I can
think of at prefent, will of themfelves occur; fo that I do~
not in the leaft doubt, but that with a little practice, all
things may be made fo convenient, that the fame character
may be feen at Paris within a minute after it hath been ex-
pofed at London; and that the characters may be expofed
fo quick after one another, that a contpofer fhall not much
exceed the expofer in fwiftnefs; and this not only at the -
diftance of one flation, but of a hundred ; for, fuppofing all
things ready at all thofe feveral ftations for obferving and
expofing, as faft as the fecond obferver doth read the charac-
ters of the firft expofer, the fecond expofer will difplay them
to the obferver of the third ftation, whofe expofer will like-
wife difplay them for the fourth obferver, as faft as his ob-
ferver doth name them to him, or write them down.

“There may be many objeCtions brought againft this way
of communication, becaufe it has not yet been put.in prac-
tice ; but hardly any that may not be eafily anfwered and
obviated.” Dr. Hook illuftrates his invention thus:

“ Let ABC (Plate X. fig. 4.) reprefent three very long
mafts or poles erected; E, the top-piece, that joins them
all together; D, a fcreen, behind which all the deal-board
characters hang upon certain rods or Jines, and may, by the
help of {mall fines conneéted with each of them, be ex-
pofed at 5 or drawn back again behind D, as occafion fhall -
require.”

XVII. Propofttions refpeding the Mechanical Power of the
Wedge, by Mr. Perer Nicuoxson of Newman-ftreet. bisa
municated by the me

Writers on Peieiates in treating of the wedge, have
frequently drawn falfe conclufions refpecting the proportion
which exifts between the impelling power applied to the
head, and ae refifling powers oppofed to the fidess and

thofe

On the Mechanical Power of the Wedge. 317

thofe conclufions have refulted from falfe opinions concern-
ing the dire€tions of the refifting powers.

It is evident, that when wood or other fubftance is fplit by
a wedge which does not fill the cleft, that is, when the angle
of the cleft is more acute than that of the wedge, the power
or action of each fide of the wedge, equal and oppofite to the
refiftance of the cleft, muft be refolved into two; the one in
the direétion of the fide of the cleft, which tends to thruft it
forward; and the other perpendicular to that direction,

- which tends to tear it afunder. It is by not attending to the

above refolution that writers on this fubje@t have been led
into miftakes ; for, inftead of confidering the powers which
a&t in thofe two dire€tions, they have imagined a fingle
power only as acting obliquely on each fide. But if the fides
of the wedge are perfectly polifhed, as we muft here confider
them, no fingle permanent power can be applied to impel
any one of them, unlefs its direction be perpendicular to the
plane of the fide to which it is applied: therefore two ob-
lique powers, applied on oppofite fides of the fame point, are
at leaft necéflary to fuftain each other and the action of the
plane; and in the cafe of the wedge above mentioned, the
direCtions of thofe two oblique powers will always be per-
pendicular to each other, as will appear obvious from the
two following propofitions.

Prop. I. Let ABC (Fig. 3, Plate X.) be a vertical fec-
tion pafling through the centre and at right angles to the ©
head and fides of any ifofceles wedge; alfo in the plane of
this feGtion, and at right angles to its fides AB, BC, and CA,
let three powers be applied, fuch, that their dire€tions may
all mutually interfeét in the axis, and their efforts fuftain the
wedge, in equilibrio; I fay, that thefe three powers are as
AB, BC, and CA refpectively.

Let LM, KI, ED be the dire€tions of thefe three powers,
which produced, interfeét each other and the axis in O.
Since, by hypothefis, thefe three powers directed to the fame

‘point are in equilibrio, and the three fides of the triangle
' ABC are at right angles to their direCtions ; therefore, by a

well

418 On the Mechanical Power of the Wedge.

well known ftatical principle, the intenfities of thefe power¢”
are as AB, BC, and CA refpedtively.

Prop. If. When an impelling power applied to the head
of an ifofceles wedge is in equilibrio with the refifting power
of a cleft, the angle of which is more acute than that of the’,
wedge inferted, then univerfally,

The impelling- power applied to the head,

"The aétion of the wedge on either fide of the cleft,

‘Phe part thereof which tends to thruft it forward,

And the remaining part, which tends to tear it afunder,

Are

As twice the fine of half the vertical angle of the wedge,

The radius,

The fine of the angle contained by the fides of the wedge
and cleft,

And the co-fine of that angle refpedtively, the wee
tadius being common.

Let Fig. 2, Plate X. reprefent a vertical fe€tion of the
wedge and cleft, fimilar in pofition to that defcribed in Pro-
pofition 1; alfo let the two fides of the cleft DH, DH be
equal, and in’ contaét-with the fides of the wedge AC, AC at
equal diftances DC, DC from thé vertex C, in which cafe
the fides of the wedge make equal angles with thofe of the
cleft. “Through either point D, draw: DF at right angles,
and equal to AC; alfo through D, draw DE, at right angles’
to DH, and complete the parallelogram DEFG. ‘Then by
Propofition 1, the line AA reprefents in quantity the impel-
ling power applied to the head, and the line DF reprefents in
quantity and dire€tion the whole action of the fide of the wedge
on that of the cleft, which by hypothefis is balanced by its refift-
ance; but the power DF is refolved into two, reprefented i in
quantity and dire€tion by DG, DE refpetively : the one, being
- jn the direétion of the cleft, tends to thruft it forward; and the
other, being at right angles thereto, tends to tear it afunder.

Therefore the powers mentioned in the Propofition are as
AA, DF, DG and DE refpettively ; but AC = DF being

tadius, thefe lines are refpectively equal to
Twice

On Galvanifm. . 319

Twice the fine of half the vertical angle of the wedge,
‘The radius, ;
The fine of the angle contained by the fides of the wedge
and cleft, ree
And the co-fine of that angle. Hence the propofition is
manifett. n

XVIII. Report of the Commiffioners appointed by the National In-
Jfitute to repeat the Experiments which have been made on Gal=
vanifm : read in the Name of the Commiffion by Cit. Hate.

From the Bulletin des Sciences, par la Societé Philoma-
thique, Thermidor, An V1.

T HE commiffion was not fatisfied with repeating a great
part of the experiments already made: they clafled them,
and rendered them complete by the addition of others which
were wanting.

I. The phenomenon of Galyanifm, taken in general, is as
follows : A communication is eftablifhed. between two points
ofa feries of nervous or mufcular organs by means of certain
determined fubftances. At the moment when this commu-
nication is made, there take place in the {tate of the organs
changes, the nature of which is ftill unknown; but which
are manifefted by fenfations more or lefs lively, or contrac-
tions more or lefs violent. Thefe mufcular contra€tions
take place even in feparated parts of the body, and with as
much force as when produced by the moft effeftual means
of irritation. ‘The feries of mufcular or nervous organs is
called the animal arc ; the other fubftances form the exciting
arc. ‘The compofition of both may be varied many different

_ Ways.

II. Among the effects refulting from the different compo~
fitions of the animal arc, the following are the moft remarka- ©
ble: A ligature made on a nerve does not intercept Galvanifm,
anlefs it be made in the part furrounded with flefh. If the

nerve

320 . Ox Galvanifine

nerve be cut, and its two ends be in contact, Galvanifim
takes place ; but if they are only brought near to each other,
without contact, it is intercepted.

III. Among the effects refulting from the different compo-
fitions of the exciting arc, we fhall remark the following :
The moft favourable compofition is when it confifts of three .
pieces, each of which is a different metal. One muft touch
the nerve, and the other the mufcle: thefe are called the
Supports, or armatures. The third forms the communication.
This is called the communicator. But one or two of thefe
may be omitted. Animal bodies, or water, may be placed
between them ; or other fubftances, either metallic combi-
nations, or all other metals, &c. may be fubftituted in their
ftead. It has not yet been poflible to determine exaétly
what are the moft ineffectual combinations ; but they have
been already clafled to a certain point, according to the de-
gree of their efficacy. Gold, filver, zinc and tin, are the
metals moft favourable to Galvanifm, when introduced into
the exciting arc.

In general a fingle metal does not act, except when all
other circumftances are favourable; but in that cafe it has
been often feen to a€t. Error, however, may readily here
arife; for, if one of the ends of the arc be alloyed, in a pro-
portion ever fo little different, the arc aéts as if there were
two metals. By rubbing one end with a different metal,
fometimes even with the fingers, or by breathing upon it,
eficacy may be communicated to it, under circumftances
where it would not otherwife have poflefled any.

Oxydes act lefs efficacioufly, ceteris paribus, than their,
metals. Dry carbon aéts as an aétua! metal. It is not ine
tercepted by water and moift fubftances, nor by the fingers
if wet; but this is not the cafe if the fingers be dry. The
energy of Galvanifm is not intercepted or diminifhed by
pieces of dead flefh. The effects of it are fenfibly checked
by the epidermis; and they are incomparably greater in

flayed

On Galvaiifin. 221

- flayed animals, or in parts of the human body from which

the epidermis has been removed.

-It cannot be faid that Galvanifm is intercepted by all idio-
eleGtric bodies; but, on the other hand, it is intercepted by
all fubftances which are {trong conductors of electricity.
Such are flame, very dry animal bones, the fteam of water,
glafs brought to a red heat, &c.

“IV. Galvanifm is influenced alfo by feveral circumftances
foreign to the compofition of the two arcs. Such as, tr. The
ftate of the parts which are fubjefted to the operation: the

_ frefher they are, the flronger are the effects. 2. The longer

or fhorter exercife of Galvanifm: fufceptibility of Galva-
nifm is in general excited by exercifing it; is exhaufted. by
continuance, and renewed by repofe. 3. The fucceffion of
various experiments. A difpofition of metals which at firft
had been ineffe€tual, has become effe€tual after a different
difpofition. Two uncertain experiments are hurtful to each
other, and become ftill more fo if made in fucceflion.

' 4. ‘Lhe ftate of the atmofphere. The atmofphere electric;

the animal on which the operation is performed charged
and infulated, the effe@t is the fame. The whole apparatus
placed under water, the effe€t remains the fame.

V. There are various artificial means to weaken or revive
the fufceptibility of Gaivanifm. Thus, a frog exhaufted and
brought near to a charged electrophorus refumed its fufcep-_

- tibility. Alcohol, on the other hand, weakens and even ex-

tinguithes it fo as never to return. Potath produces the
fame effe&, only flowly. According to M. de Humboldt,
this fuiceptibility is in many cafes reftored by oxygenated
muriatic acid gas. The commiffioners did not obferve this
circumftance ; but they propofe to refume the fubject, and to
repeat feveral other experiments of that learned philofopher.

They have already repeated thofe on the action of Galvae
nifm on the heart, and have obferved, as he did, that its
action is the fame as on the voluntary Pai lahe and that it
accelerates their movement.

_ Vou. I. ¥ XIX. OF

bgaas iy

pb. Of an Attempt to make the Maple Sugar alove an
hundred Years ago. Communicated by Dr. THORNTON,
LeGlurer on Medical Botany at Guy's Hofpital, &s'c.

Ir appears, by the following correfpondence between
Dr. Robinfon and Mr. Ray, that the property of the Ame-
rican maple of yielding a faccharine juice was known above
a century ago, and that attempts were even made to pro-
duce fugar from it :

Dr. RoBinson fo Myr. Ray.

“ Dear Sir, London, March 10, 1684.

I have enclofed you fome fugar of the firft boiling got
from the juice of the wounded maple: Mr. Afhton, Secre-
tary to the Royal Society, prefented it to me. T'was fent
from Canada, where the natives prepare it from the faid juice;
eight pints yielding commonly a pound of fugar. The In-
dians have practifed it time out of mind; the French begin

now to refine it, and to turn it to much advantage. If you.

have any of thefe trees by you, could you not make the
tial, proceeding as with the fugar cane ?”

Anfwer to Dr. Rosinson.

“* Black Netley, April 3, 1684.

“ ‘Yours of the roth inftant I received, and therein an
enclofed fpecimen of the Canada fugar, a thing to me
firange and before unheard of. It were well worth the
experiment you mention. I therefore engaged a friend
and neighbour of mine, an ingenious apothecary, whom I
employed yefterday to boil the juice of the greater maple,
a tree which grows freely half a mile off from my refidence.
Having made an extraét, he found a whitifh fubftance, like
to brown fugar, and tafting very fweet, immerfed in a

fubftance of the colour and confiftency of moloffes. Upon »

curing, I have no doubt it will make perfect fugar. When
it is cured, I will give you a farther account of it.” 4

‘Here

Royal Society of Copenhagen. . 322

Here the matter ended ; and after the paper given you on

the American maple (fee p. 182), 1 hope the fubject will be

again purfued with ardour in this country, and this curious

inveftigation turn of profit to this nation.—! fhall fend you,

for your next number, a paper on the mulberry tree; and
the rearing of filk-worms.

INTELLIGENCE,
LEARNED SOCIETIES.

DENMARK,

Tar Royal Society of Copenhagen has this year pto-
pofed a gold medal, value 100 rix-dollars, for the beft an
{wer to each of the following queftions.

I. HISTORY.

Quenam gentes ante Norvegicos Americam invenerint,
et itinera per mare in hanc terre regionem inftiterint ?
Quoufque deteéta Norvegicorum in America prefertim Auf-
trum verfus extenfa fuerint ? Quz hac de re conftitui po-
terunt, argumentis et conjecturis ex {criptis, monumentifve,
vy. c. munimentis, eedificiis, linguis, traditionibus Americanis
probanda funt.

«© What nations difcovered America, and kept up an in-
“ tercourfe by fea with that country before the Norwegians?
“© Flow far did the diicoveries of the Norwegians in America
* extend towards the South? The proofs and grounds of
* conjecture muft be drawn partly from written documents
“and partly from monuments, fuch as fortifications, edi-
* fices, languages and traditions {till exifling in America.”

Il. IN THE MATHEMATICS.

Invenire funétionem omnium quantitatum que con-
jundtim determinant magnitudinem effeCtus calorifici, cujuf+
‘cunque materici igni accipiendo apte in re familiari ufitate,
tam ligni, quam cefpitis caminarii et lithantracis, feu carbo-
num foffilium cujufcunque fpecici.

; Fire fEquatie

Ro4 Royal Society of Copenbagen.

ZEquatio quefita ad minimum determinanda eft pro qua
tuor diverfis cafibus. 110, Si lignum vel cefpes eaminarius
feu carbones foffiles in fornace deuruntur, ut fpatium aéris
inclufum, e. gr. cubiculi calefieri poffit. da, Si in foco
fluido cuicunque coquendo infervient. 3¢i0, Si materic molli
indurandz, e. gr. in camino laterario lateribus coquendis.
40, Si materiis duris liquefaciendis, e. gr. metallis five in
clibano five in uftrina fundendis infervient.

Singulz zquationes experientia duce ita analyfis ope de-
tegende et inftituendz -funt, ut ex ipfis computari poflit
ratio effectus calorifici eque ac ufus ceconomici cujufcunque
fpeciei ligni, cefpitis caminarii et carbonum foflilium.

“To difcover the functions of all thofe quantities which
“ conjointly determine the degree of the effe& of heat pro-
“ duced by every combuftible fubftance employed for econo-

- mical purpofes, whether wood, turf, foflil, or pit-coal of
“¢ whatever {pecies.

“ The required equation muft be determined for four
*€ different cafes. 1/?, When the wood, turf, or pit-coal is”
‘burnt in a ftove, that the inclofed quantity of air, for
* example of a chamber, may be fufliciently heated. ad/y,
*¢ When they are employed as fuel. for boiling any liquid.
“ 2dly, When they are employed for hardening any foft
“ fubftance, for example, in a brick-kiln for baking bricks.
** athly,When employed for melting hard fubftances, fuch,
“ for example, as fufing metals either in an eflaying anrhoge
* or a melting furnace.

_. “ Each of thefe equations muft be fo deduced from ex-
“¢ periment, by the help of analyfis, that they may ferve for
** computing the ratio of the effects of the heat and the
“ economical advantages of each fpecies of wood, turf, and
S¢ pit-coal.”

III. IN PHYSICS.

Experimentis invenire maximum caloris gradum quem
calefa€ti vapores aquei cum aliis corporibus communicare
poflunt ? An ea pars aque in olla Papiniana, que non in

vapores

Medical Society at Barcelona. 325.
vapores calore mutata eft majorem, quam 212° Fahren,
temperaturam habere poteit ?

“To determine, by experiments, what is the higheft de-
“© sree of heat which can.be communicated to other bodies

' “by the fteam of water? Can that part of the water in

“« Papin’s digefter which is not in the form of vapour ac-

*¢ quire a higher degree of heat than 212° of Fahrenheit ?”

Iv. IN PHILOSOPHY.

Quinam funt notabiliores gradus per quos philofophia
practica, ex quo tempore fyflematice traCtari coepit, in eum,
quem hodie obtinet, ftatum pervenerit ? é

“What are the moft remarkable fteps in the progrefs
« which practical philofophy has made, from the time it was
€ brought into a regular fyf{tem down to the prefent period ?”

The anfwers to thefe queftions muft be tranfmitted, poft
paid, before the end of June 17¢9, to Profefior Abildgaard,
fecretary to the fociety. All men of letters, the members
of the fociety alone excepted, are invited to this competi-
tion, and their anfwers may be written in Danifh, German,
French or Latin. -The authors are requefted not to infert
their names in the title of the papers, but to diftinguifh
them by a motto, which muft be infcribed alfo on a fealed
note containing their name and place of refidence.

SPAIN.

The Royal Academy of Pradtical Medicine #& Barcelona

has propofed the following queftion as the fubject of a
prize: |

To determine whether cold baths, adminiftered as a

; prefervative or as a remedy to thofe attacked with dif-

orders of the breaft, are ufeful or prejudicial ; and what

may be their effedts and advantages according to circume
ftances ?

The prize will be a gold medal, value 375 rials; and the

memoirs muft be tranfmitted, with the ufual formalities, to

x 3 the »

326 French National Inftitute.

the fecretary of the academy, in the courfe of the month:
of October 1799.

NEW AGRICULTURAL SOCIETY.

A Society for promoting agriculture and manufactures
has lately been eftablifhed in Finland, /t will publith its
tranfactions monthly, a thoufand copies of which are to be
printed in the Finnifh, and a thoufand in the Swedith lan-

guage.

FRANCE.
‘The following prize queftions were propofed by the
French Nationa] Inftitute of the Arts and Sciences, in the
public fitting of Meffidor 15th, year VI,

GEOGRAPHY.

_ To determine what are the grand revolutions which have
taken place on the globe, and which are either indicated or
proved by hiftory ?

The prize will be a gold medal of the weight of five
he€togrammes, and will be adjudged in the public fitting of
the 1sth of Nivofe, in the year VILL

MoRAL SCIENCE.

The Clafs of the Moral and: Political Sciences had pro-
pofed, for the fubject of a prize for the year VII, the fol-
lowing queftion :

What are the inftitutions beft balenbitcd to found the
morals of a people?

The effays tranfmitted on this fubj>& not having anfwer-_
ed the required conditions, the clafs propofes the fame fub-
jeét again, and in the public fitting of Vendemiaire the
sth, in the year Vil, will publifh in a new programme fome
jiluftrations of this important queftion. ‘The prize will be
five he€togrammes of gold ftruck into a medal, which. will
be adjudged in the public fitting of Nivofe the 15th, in the
year VIII. No anfwers will be received after the rsth of
Vendemiaire, the fame year.

, class

French National Inftitute. 327
GLASS OF THE MATHEMATICAL AND PHYSICAL SCIENCES.

PHYSICS.

This clafs had propofed, in the year IV, as the fubje&t of
a prize to be adjudged in the public fitting of Vendemiaire
of the year VII, the ufes of the liver in the different claffes
of animals. This fubject fo important, which the academy
of fciences had propofed.in 1792, and which the Inflitute
thought it its duty to continue to hold forth to the examina-
tion of the learned, was not treated in the manner it expect-
ed. It received only one memoir, in which the queftion was
not in the fmalleft degree illuftrated; and of which the
author had wandered into the wide field of the ancient hy-
pothefes, without availing himfelf of the anatomical and
chemical refources pointed out by the Inftitute in its pro-
gramme.

This paucity of memoirs, on a fubje& which concerns
one of the nobleft and moft ufeful branches of phyfics, indu-
ced the Inftitute to fuppofe that the magnitude and extent of
the queftion; the feries of the refearches neceflary for-treating
it in a proper manner ; and above all, the difficulty of finding
. united in one man the chemical and anatomical knowledge
requifite for folving it, were the caufes which had deterred
competitors from coming forwards. Without abandoning
the idea of prefenting to the zeal of philofophers a queftion
of fo much importance, the In{titute has thought proper to
divide it into two branches, and to make it the fubject of
two prizes, by adding to the medal which was to have been
adjudged in the year VII, for the whole queftion, that
which it has at its difpofal for the prefent year. It: pro-
pofes, therefore, as the fubjeét of two prizes, to determine
the functions of the liver, feparating what relates to the
anatomical ftructure of the hepatic fyftem, from what relates
to the chemical examination of the liquids and folids be-
jJonging to that fyftem.

The object of the firft of thefe prizes will be: the form,
fitvation, fize, comparative weight, and defeription of the

| Y¥ 4 tifa

~~

328 French National Inflituté,

tiffue of the veffels, ducts and appendages of | the liver, con-
fidered in the principal claffes of animals, from man down
to infects, molufcz and worms.

The object of the fecond will be: an analyfis of the
hepatic or cyftic bile in the different bag: of animals a&
above mentioned. ©

The memoirs of thofe who intend to be candidates for one
or other of thefe prizes, or for the whole in one effay,
muf be tranfmitted, poft paid, to the fecretary of the clafs
of the mathematic. and phyfical {ciences, before the firft of
Nivofe in the year VIII.

The prize for each queftion will be a gold medal of the
weight of a kilogramme ; and will be adjudged in the fitting
of Germinal rsth, in the year VIII. The memoirs may be
written in French or in Latin, or in whatever language the
authors choofe.

Nitice of the Labours of the Clafs of the Phyfical Sciences during
- the preceding three Months: By Git. Lassus, Secretary.
Read on the 15th Meffidor (July 34.)

In the clafs of the Phyfical Sciences during the laft three
months, feveral memoirs were read relating to chemiftry,
natural hiftory, rural ceconomy and medicine, as applicable
to. animals as well as man. Cit. Guyton, in treating of
the anomalies in affinitics, fhewed that thefe apparent devias
tions open to chemifts a vaft field for new refearches. He
examined why there is no combination between the azot and
oxygen which exi't fo abundantly in the atmofphere, and in
a flate of expanfion generally fo favourable to an union.
He likewife pointed out the means of producing it in an
apparatus capable of fupporting nine ‘or ten times the weight
of the atmofphere.

The fame chemift employed himfelf alfo in the recipros
eal decompofition of falts, ata temperature below freezing 5
_ aphenomenon, the obfervation of which is of fo much ims;
e- portance

,

er

French National Inflitute. 329

portance in falt works. He difcovered the caufe of it in

the difengagement of caloric, which becomes a difaggrega-
tive power. Since chemifts have extended their refearches
to the matter of heat, it is well known that carbon is one of
the weakeft condu“ors of it. Pyrometrical experiments,
have proved to Cit. Guyton, that a body enclofed in carbon
does not receive from the fame fire but two thirds of the
heat received by a fimilar body placed in filiceous fand.
The confequences to be drawn from this fact will ferve to
improve the proceffes employed in reduétion and fufion.

_ Chemifts have hitherto been checked in many of their ex-
periments, by not being able to increafe the intenfity of fire.
The application of an hydraulic principle to the conftruétion
of Macquer’s furnace, furnifhed Cit. Guyton with the means |
of increaling heat to fuch a degree, that a crucible of platina
began to melt ; a circumftance never before obferved.

- Profeffor Klaproth, at Berlin, had announced that the
colouring matter of the emerald was iron; but the laft analyfes
of Cit. Vauquelin prove that the emerald is compofed of fili+ ~
ceous alumine, a particular earth which has been called glu- »
cine, and the calx or oxyde of chrome; fo that the emerald
as well as the beryl or sigue-marine are two ftones perfectly
fimilar, and compofed of the fame principles, the colouring
matter excepted. (See p. 204.)

By an accurate application of chemical knowledge to the
art of dyeing, Cit. Chaptal has difcovered a fimple and eafy
procefs for communicating to cotton a darker or lighter

_chamoy yellow (jaune chamois). Ly. uniting alumine to the

oxyde of iron, this chemift has been able above all to give to
his colours a foft and velvety appearance, which they cam
never acquire when that oxyde is employed alone. He has
examined the different methods of combining that oxyde.
with the red of madder, to form a violet colour, and has re-
‘duced to fimple principles, operations which were exceed-
ingly complicated. He has fhewn the reafons why no other
aftringents, whatever be the dofe employed, can be fubfti-

peed for gall-nuts in dyeing cotton.
9 To

330 French National Inftitute.

To give to the fame ftuffs that beautiful red colour, known
under the name of the Turkifh or Adrianople red, dyers em-
ploy foda, oil, gall-nuts, fumach, madder, the fulphate of
alumine, and feveral other fubftances. Cit. Chaptal has ex-
amined what is the action of the three principal mordants,
‘oil, gall-nuts, and alum, employed in dyeing cotton 5 and by
defcribing the moft complex and ob{cure operations in dyeing,
he has fhewn what chemiftry can do towards improving the
arts, when the practice of it is direted by a fimple and
clear theory *.

The employment of foda is not confined to the dyeing of
cotton ; that brought from Spain is of great ufe alfo in foap
manufactories, glafs-houfes for making white glafs, and in
bleaching. As Franee expends annually the fum of four —
millions for that foreign article, it was of importance to en-
courage the cultivation of the plant which furnifhes the foda
of Alicant. In this refpe& Cit. Chaptal and Teffier have
been of great fervice: the firft, in proving by the experience
of many years, that the plant which furnifhes the foda of
Alicant may be fuccefsfully cultivated on the fouthern coafts
of France; and that the foda it produces is abfolutely of the
fame quality as that of Spain; and the fecond, by giving all
the neceflary inftru€tions refpeCting the cultivation, and
burning of the plant in order to convert it into foda.

Some years ago Cit. Clouet, a member of the Inftitute,
had fhewn the poffibility of converting iron into caft fteel,
without, having récourfe to previous cementation. This
procefs, which he has brought to perfeCtion, is the more
valuable to the arts which require caft fteel, as it may be
produced without cementation or natural fteel in every
place where there is good iron, a mixture of: alumine and
filiceous earth, and chalk. i

. It is well known that the goodnefs of artillery depends, in
an eflential manner, on the operations which relate to the
miature and fufion of the metal. Tin, which forms a part

* See Chaptal’s Paper on this fubjeét, page 274.

‘of

French National Inflitute. 331

of its compofition, is expofed fometimes to fo great heat
while the piece is ufed, that it becomes fufed, which gradu-
ally renders the cannon defeétive. To remedy this incon-
venience, Cit. Baumé propofes to harden the copper with
nickel, or with what was formerly called regulus of anti-
mony, neither of them being fo fufible as tin.

Experiments made at Rambouillet, and in different parts
of France, have already fhewn the pofibility of propagating
and preferving in all their purity fheep of the Spanifh breed.
Cit. Gilbert has communicated on this important point of
rural economy the fulleft inftru@tions, and given the beft
founded hopes that thefe valuable animals may be reafed in
the territorities of the republic, without ever degenerating.

The conquefts of our army of the North, by augmenting
the riches of the Mufeum of .Natural Hiftory at Paris, have
given Cit. Lamarck an opportunity of pointing out with
precifion the diftin@ive charaéterifing marks of the common
euttle th (jepie officin:tis), the calmar or fea fleeve (/epia
oligo), and poulpe or eight armed cuttle (/epia offopus),
which had been confounded and claffed in one genus. He
has rectified an error received among fome naturalifts, who
confidered as the animal which forms the argonauta or
paper failor, a poulpe which is accuftomed to lodge itfelf in

that fhell, in the fame manner as the crab called the hermit

takes up its lodging in different kinds of fhells.

Cit. Cuvier, in a very long memoir on the organs of the
voice, fhews that the greater part of birds, independently of
the inferior glottis, which is the principal organ of their
voice, have a fuperior larynx, by which mechanifm they are
the more enabled to vary their tones, as by its means they
can more ealily change the ftate of their glottis, the length
of their trachea, and the aperture of their upper larynx. It
refults from this organifation, that the graveit tones, and
the harmonics of thefe tones, are produced by a prolongation
of the tracheal artery and the greateft relaxation of the
glottis; while by a fhortening of the trachea, and a contrac~
: t10Q

332 Experiments on Sound. .

tion of the glottis, the bird produces tones fo much higher
as the trachea is fhorter, and all the harmonics befides which »
correfpond to that degree of contraction.

Obfervations which confirm the utility of the muriate of
mercurius dulcis in the cure of the fmall pox, by Cit. De-
feffarts, as well as the profound refearches of Cit. Huzard on
a malady which affects the organs of generation in horfes,
engaged likewife the attention of the clafs.

Several of its members have made it their particular care
to confirm, by repeated experiments, the phenomena of
Galvanifm. (See Report of the Commiflion appointed to
examine this phenomenon, p. 319.)

PRODUCTION OF SOUNDS BY DIFFERENT GASES.

J. F. Jacquin, profeffor of chemiftry at Vienna, in 2
letter to M.-Delametherie, gives the following account of
fome curious experiments which he made Jately on this fub-
ject: “© Profeffor Chladni at Wittemberg, already cele-
brated by feveral difcoveries in the theory of the phenomena
of found, induced me, during his refidence at Vienna, to
make experiments on the property of differegt gafes con-
fidered as fonorous bodies; and particularly on that gas
which conftitutes our atmofphere, and ferves as the organ of
voice. We took a glafs bell furnifhed at the top witha
brafs cock, fuch as that ufed for filling bladders with gas,
and made the internal aperture of the cock to communicate
with a fmall tin flute, about fix inches in length. This bell
being placed in the pneumatic tub, and filled with gas of any
kind, a bladder with a cock, and filled with the fame gas as
the bell, was fitted to the cock of the bell, and by prefling
the blader gently the flute was made to found. Compara-
tive experiments were repeated in this manner with atmo-
{pheric air, oxygen gas, hydrogen, the carbonic acid, and
nitrous gas. ‘The ftrengtk of the found was always the fame:
but, compared with that in atmofpheric air, the oxygen gas
gave half a tone lower; azotic gas, prepared different ways,
as: | SSC) 2 gave

“o

Experiments on Atmofpheric Air. 333
gave almoft always a femi-tone lower; hydrogen gas gave
nine or eleven tones higher; the carbonic acid gas a third
lower; and the nitrous gas almoft the fame: a mixture of
oxygen gas and azotic gas, in the proportion of atmofpheric
air, gave again the tone of the laft mentioned air, that is to
fay, a femi-tone higher than each ‘of the compound gafes
alone. As long as the two gafes were not uniformly mixed
there was a frightful difeord. Chladni has promifed to
pudlith a full account of thefe sik beep experiments,
which ‘differ entirely from thofe of Dr. Prieftley.

EXPERIMENTS ON ATMOSPHERIC AIR.

On the r4th inftant, at 7 o’clock in the evening, Cit.
Garnerin and Cit. Beauvais afcended in a balloon from the
garden d’Apollon, at Paris. At the height of nearly 40@
toifes Cit. Garnerin let fall a cage, attached to a parachute,
and containing a cat, which fell very gently near the Port-
au-Bled. After 20 minutes the balloon defcended at Nan-
teuil, diftant from Paris three leagues. At that place, Cit.
Beauvais, aide-de-camp to General Moulins, quitted Cit.
Garnerin, who departed at half paft three in the morning to
complete his a€rial voyage, by taking a long flight. Cit.
Frederic Humboldt, a celebrated philofopher, had begged
Cit. Garnerin to fill with air a fmall flafk with a ground
ftopper. Cit. Garnerin emptied the water which it con-
tained at the height of 669 toifes (1303 mretres) above -
Paris. Cit. Beauvais brought back the bottle, filled with
atmofpheric air, to Cit. Humboldt, who was defirous to know
ifthe carbonic acid gas aftends to fuch elevated regions.

The obfervations of Sauffure, made on the fummit of

‘Mount Blane (at the height of 2.480 toifes), announced its

exiftence there ; but this philofopher was in an atmofphere
modified by the proximity of rocks. Cit. Humboldt found
in the air brought back by Cit. Beauvais, which had not
‘been under the like influence, between 8 and 10 milliemes
of carbonic air. Here then is a very heavy a@riform fluid
carried to the moft elevated regions of the atmofphere.

: The

334 Mineralogy.

The air of Paris, colle€ted on the following midnight,
and analyfed by means of the nitrous gas and fulfate of iron,
was found to contain 05276 of oxygen gas. ‘The air cols
lected by Cit. Garnerin’ contained only 0,259 of oxygen.
The firft was at 103 degrees, the fecond at 108 of the eu-
diometer. The air of the high regions was confequently
5 degrees, or 0,017 (almoft equal to 0,o2) more impure than
the air at the earth’s furface*. ‘Lhis difference is very
confiderable, when we reflect that the greateft-or leait purity
of the atmofphere does not differ near the earth’s furface
but 0,03 of oxygen,

MINERALOGY.

Mr. Donatp Stewart, who has been employed for fe-
veral years paft as travelling mineralogift to the Dublin s5o-
ciety, has lately arrived at Belfaft, after having paffed over,
in his Jaft journey, the counties of Meath, Cavan, Ferma-
nagh, Donegall, Derry, and Antrim. He had before ex-
plored the greateft part of the South and Weft of Ireland.
He has made many new and curious obfervations, and col-
lected numerous fpecimens, illuftrating the natural hiftory,

and affording materials for the arts, manufactures, and agri-_

culture of that kingdom.

Though not educated to thofe purfuits, he has been inde-
fatigable in his refearches, and fuccefsful in his difcoveries ;
and indeed he appears to be the firft perfon who ever at-
tempted making any general furvey of that ifland with a
view to its mineralogy.

Some imperfect accounts of the native plants of Ireland
have been publifhed by Rutty, Wade, and fome other gen-
tlemen, who, during the refidence of Lord Chefterfield as

* It is eafy to account for the atmofphere containing more oxygen near
the earth than in the higher regions ;. the vegetables which grow on its
furface being the principal agents employed by nature to reftore the purity
of the atmofphere: but it is pot fo eafy to account for the prefence of
carbonic acid gas at fo greata height. pir.

‘ viceroy,

Mineralogy. 335
viccroy, formed a fociety in Dublin under his patronage’:
but the mines are not defcribed in their effays, nor are there
any catalogues of their foffile produdtions publifhed.

Mr. Stewart has been upwards of twenty years engaged
exclufively in this purfuit, and has already depofited 1300
different mineral fpecimens in the cabinet of the Dublin So-
ciety. But as few of his cbfervations have hitherto been laid
before the public, the following extra&t from his notes
‘may prove acceptable to our readers:

« I was enabled,” fays Mr. Stewart, “ by difcovering rich
quarries of limeftone and marle, in feveral eftates where they
were never before known either to tenant or landlord, to be
» acceflary to the fertilization of the moft barren lands. In
the eftates of Lord Palmerfton and Ormby Jones, Efq. in the
county of Sligo, I afforded the greateft pleafure and advan-
tage to the poor inhabitants, by demonftrating to them that
the great rocks, which they called Serpent Rocks, and which
they were gazing at with ftupid or fuperftitious admiration
‘for ages, contained moft excellent lime. Thefe quarries are
at their doors; whereas formerly they carried the fcanty pic-
tance of lime they were able to procure from nine or ten
miles diftance. Having turf at home in abundance, they are
now fupplied with lime at as cheap a rate as any people in
Europe. ;

_ ©TJ obferved to. the prieft who accompanied me to the —
Serpent Rocks, that this muft have been the place to which
my countryman (St. Patrick) had colle@ed all the ferpents
of the kingdom. ‘The cliffs extend a mile in front, dip to-
wards the fea weftward, and run to an indeterminate length
into the country. No block can be raifed in thefe cliffs that
is not replete with petrifaCtions; and the fifh appear te lie
promifcuoufly as if thrown out of a net. There may be
about one-twentieth of the whole rock compofed of thofe
petrified fifh or ferpents. The ftrata or beds are very regu-
Jar, and of different thicknefs. They contain alfo fome large
round fhells as yellow as gold; fo that if chimney-pieces

were

"936 Botany, &5'c.

were wrought here they would be very valuable, ag the fiffs
and fhells would: afford very lively and interefting objets
upon the polithed furface. The Cobham marble is reckoned
of great: value, from the reprefentation Of ruins and land-
Acapes which fometimes appear upon it; but it would fall
far fhiott;. i in,my opinion, of the fingular and ferptiling figures
: with, which thefe. rocks abound:”-

~2..Ewo fmall blocks of,this ftone are depofited at the Dub-
Ha Sootety: ta

e+
ghee) 4

BOTANICAL EXPEDITION.

The following is a lift of the objeéts of natural hiftory,
and other curiofities, brought home by Captain Baudin, com-
‘mander-in chief of the botanical expedition, in the flute
‘La’ ‘Belle Angilig "er One hundred. and ninety cafks, con-
‘taining about’ 335 00 living plants, and in a ftate of vegeta-
tion} four boxes of zoophites and lithophites; a box con-
‘saining the horns of quadrupeds, and other objeéts; a box
Sontaining vafes of porcelain, and other objects; a box of
‘paintings; a box of bows and arrows, and other objeéts; two
boxes of madrepores 3 two boxes of ftuffed birds; two boxes
of fpecimens of wood; a box of quadrupeds and fifhes in
fpirits; two boxes of infects and quadrupeds in fpirits; four
boxes of plants in fpirits; a box of cruftaceous animals and
polypes ; four boxes of feeds ; four double boxes of infeds;
three cafks of fhells; a cafk of melocaéti in fpirits ; living
birds; three apes; a crab-eater (chien crabier); eleven planks,
and one log of mahogany; a box of mifcellaneous articles ;
a cafk of minerals; four boxes of petrifactions and eagle-
ftones (<codes} ; a box of bitumen, &c.

.

gaacset
“ -~

THE

PHILOSOPHICAL MAGAZINE.

SEPTEMBER 1708.

ES

1. Obfervations on the Account of the Juppofed Orang
Outang of the Eaft Indies, publifbed im the Tran/aétions
of the Batavian Society in the Ifland of Java. By DE
GroFFROY, Profeffor of Zoology at the Mufeum of Natural
Hiftory. From the Journal de Phyfique, 1798. .

Baron yon Wunrns, the author of this account *,
fuppofing that the obje&t of his examination was that
wonderful being, fo much celebrated in Europe, by means
of which naturalifts imagine they can trace out, through
fhades almoft infenfible, the gradation from man to animals,
made no hefitation to give to his ape the name of the large
orang outang or pongo. But, inftead of haying an opportu~-
nity to obferve this fingular {pecies, which had occupied fo
long and in fo vague a manner the attention of naturalifts
and philofophers, and with which, it is faid, Maupertuis

-would have preferred two hours converfation to that of the

moft learned focieties in the world, Wurmb did not even
fee an ape of the fpecies of the orang outang. His obferva-
tions, however, are no lefs valuable, fince the object of them
is not only a new fpecies, but a fpecies of a peculiar form,

* For Wurm)’s defe-iption of this animal fee page 225-.

Vou J, rs a

38 G Obfervations on the Orang Outangs si
in which are united,, befides the charaéterifing marks pros
per to it, and which are not to be found in any other of the
mammalia, fome others very extraordinary which belong to
animals extremely diffimilar. To bring forward then to
public notice a differtation almoft unknown, and on an
animal, which, though defcribed fome time ago, has not yet
been comprehended in the catalogues or fyftems of natural
beings, is rendering a real fervice to fcience. But this is
not enough: it is neceflary to prevent that- confufion of
names which is always followed by a confufion of ideas 5
for the defcription of Wurmb, which is not fufficiently
ample, and which befides is unaccompanied by a figure,
does not:afford naturalifts the means .of afcertaining whether
the animal defcribed be rather a new fpecies than the pongo;
and I have been able to determine this point only by com-
paring the fkeleton of Wurmb’s ape with thofe of different
orang outangs preferved. in the colle&tion of the Mufeum of °
Natural Hiftory. This fkeleton of Wurmb’s ape, one of the
moft curious and moft valuable in the national collection,
will furnifh us with very important obfervations, that may
ferve to give a better idea of the fpecies in queftion, than a
defcription of the external parts. . (See Plate XI.) | ’

This animal, in thé feale of beings, occupies almoft the
laft rank in the numerous family of the apes. The fingular
conformation of its head places it between the mandrils
(/imia maimon et mormon L) and the allouates (jimia feni-
culus). However, if, without fixing on this characterifing
mark, though of great importance, we adhere to thofe ac-
cording to which fyftematic authors have formed for apes
genera and. divifions, the want of a tail will make it an
animal nearly related to the gibbons and orang outangs,
But I\do not think it neceffary to endeavour to prove that
the latter mark is very infufficient to point out the real
affinity of beings. A tail is a fuperfluous appendage, and

‘ almoft foreign to the bodies of animals. . This organ can in
no cafe have any influence on their economy, nor even .on

: bar. “their

.
Obfervations ¢ on the Orang Oulang: 339°

their habits. We might as well fay that fome fpecies of
the genera of the lemur, cavia, erinaceus, &c. w hich have no
tail, are fimilar to the orang outangs; which would be an
abfurdity. On the contrary, in a family like that of the
apes, where all the principal organs exhibit no remarkable ’
numerical difference, and where the teeth, fingers and
tongue have a perfect refemblance, the form of the cranium,
is the moft important confideration in examining the real
affinity of thefe animals, and may ferve as a bafis for their
generic divifions; fince it appears that the fize and convexity
of the cranium indicate fenfibility, as the prolongation and
fize of the muzzle indicate brutality:

But what is moft ftriking in the {kull of Wurmb’s ape 1s
the exceffive prolongation of the muzzle; and as this muzzle
dequires fuch a bulk only at the expence of other neighbour-
ing parts, it happens that there is no apparent forehead ;
that the offeous box which inclofes the brain is very {mall,
and that the occipital foramen is fituated in the pofteri ior
part of the head. The muzzle, the fize of which feems te
form the principal chara¢terifing mark of this fpecies, is re-
markable not only for the enormous thicknefs of the jaw-
bones, but alfo for the extraordinary bulk of the incifive
and canine teeth with which it is armed. The incifive ex-
ceed in fize thofe of the lion; and the canine, in that refpett,
are not much different: fo that, though thefe incifive and
canine teeth, except in bulk, have a near refemblance to
thofe of other apes, we are tempted to confound the head of
the one in queftion with that of the moft carnivorous ani-
mals. Another confideration feems in fome manner to fup-
_ port this affinity. The occiput rifes to a point, and forms a
pretty large and thick quadrilateral protuberance, front
which arife three offeous ridges, no lefs apparent and no lefs
folid than thofe of the lion: two of thefe ridges proceed in a
lateral dire&tion to the auricular apertures, and haye from,
four to five lines of elevation; another proceeds to the ver-
ter, then divides itfelf above the forehead, like that of the -

Za lion,

tg
348 ’ Objfervations on the Orang Outang. '

lion, into two lateral branches, and continues to the external,
fide of the upper edge of the orbits. Thefe fmall ridges are.
more diftiné in the ape of Wurmb, and form, with the
upper edge of the fockets of the eye, an equilateral triangle.
But thefe charaéterifing marks, already fo fingular in this
ape, will aftonifh us ftill more by their combination with
others at leaft equally ftrange. The head has the form of.
half a pyramid, and the auricular apertures are placed far
above the os palatinus; fo that a line let fall from the auri-.
cular apertures to the internal edge of the os palatinus would
form, at the point of its interfection with the horizontal line,
an angle of 25°. This has been already obferved in the
allouate, where fuch a fingular conformation is neceffary on
account of an extraordinary fwelling of the os hioides.

The anatomical reader will, no doubt, be perfuaded, after
what I have faid, that the ape of Wurmb can in no cafe
fupport itfelf on its two hind legs, but that it muft always go
on all-fours. It is, indeed, on the pofition of the occipital
foramen, according to the learned obfervations of Dauben-
ton, that the greater or lefs degree of aptitude for walking
upright chiefly depends. In man, whofe occipital foramen
is nearly in the centre of the bafe of the cranium, the head
is placed on the vertebral column in an almoft perfeét equi-
librium ; but if the occipital foramen is removed backwards,
and particularly to that point where it 4s obferved in the ape
of Wurmb, the equilibrium is deftroyed; the weight of
the head carries with it the body, and obliges the animal ta
ufe for its fupport, and for walking, thofe anterior extremities
which in man ferve only for grafping. of

Before we can draw any conclufion on this point, in re-
gard to the ape of Wurmb, and before we affirm, that, ac-
cording to the pofition of its occipital foramen, it cannot
walk on two legs, let us confider it in its whole organifation.
We are not yet acquainted with all the immenfe refources
of nature. We do not yet know to what degree it can en-
large, and render ufeful, organs the rudiments of which only

exit

_ Obfervations on the Orang Outang. 341

‘exift in the greater part of animals to compenfate for others
which fhe may have rendered too prominent. But, indeed,
all the reft of the organifation of the ape of Wurmb an-
ounces a biped animal. Its pelvis is not completely paral-
lel to the fpine; its os caleaneum has a flat part, upon which,
like man, it may find a folid feat; and, in the laft place,
its arms have an immoderate length like thofe of the gibbon,
fince they reach almoft to the external malleolus. This laft
eharaéterifing mark, to which no attention has hitherto
been paid, appears to.me one of the fureft indications of a
biped walk. Apes muft take advantage of the great length
Of their anterior extremities, by extending them in all di-
rections ; they muft make ufe of them as of a balancing pole
to keep themfelves in equilibrium, or to reftore themfelves to
it when they have been expofed to a fall which obliges them
to make only a gentle inclination of the body.

In a word, a particular organifation reétifies the difad-
vantages which refult, in walking ereét, from the length of
the muzzle, and the pofition of the occipital foramen being
removed farther back. In all the known mammalia, the

fpinal apophyfes of the cervical vertebra are fhorter than
thofe of the lumbar and dorfal vertebrez. The cafe is the re-
verfe in the ape of Wurmb; and, according to the judicious
remark of Cuvier, thefe apophyfes of the cervical vertebrae
have this great length, to form more powerful and more nu-
merous bonds with the large mufcles of the neck which pro-
ceed on the occipital ridges. Thus nature by another me-
chanifm has provided for the fupport of the head of W urmb’s
ape on the fpinal column; and by thefe means it can keep

_ itfelf erect, and run in that pofture.

I fhall not purfue any farther an explanation of the cha-
%. racterifing marks which it exhibits to naturalifts. I have
~ faid enough to prove that it is not the orang outang or
a pongo, but that it ought to be confidered as a {pecies un-
known before the publication of Wurmb’s memoir. I am
far from reproaching that obferver for his miftake. At the
Z 3 tine

>

bs"
gt”

342 _ Method employed to prepare Soy.

time when he wrote his defcription the natural hiftory of the
orang outangs was inyolved in fuch obfcurity, that he muft
naturally have confidered his ape to be the fame animal as
the large orang outang or pongo of Buffon. Naturalifts

were then. far from being convinced that this animal, fuch

as it is defcribed in the immortal work of that celebrated
author, is an imaginary being to which Buffon has affigned
a form and characterifing marks, by confounding, under
the fame name, and in the fame defcription, fix different
fpecies of apes defcribed by travellers,

Il. Account’ of the Methods employed in Japan and China to
prepare Soy, with fome Obfervations on the Bean from
which it is produced. By Profefor BECKMANN.

Turs article, which is a brown faline liquor, imported to
Europe from the Eaft Indies, is employed for feafoning va-
rious kinds of difhes, and improving the tafte of different
fauces. It is brought from Japan in {mall wooden veffels,
and alfo from China and other parts of India in glafs flafks,
feveral of which are packed together in a wooden box,
The ufe of it has been long general in the Eaft Indies;
where it is placed on the table at each meal, inftead of falt,
for the purpofe of dipping in it aet fifh, and other kinds
of food.
- The Japanefe are faid to be the inyentars of this article ;
and, at prefent, their foy is preferred to any other; though it
is afferted by connoiffeurs that this preference arifes more
from the price than the goodnefs. In my opinion, it was
firft introduced in the European commerce in the prefent

_ century; for it is not to be found in the old catalogues of

goods; in Saavary’s or Ludovici’s diétionaries, nor in the
old books on cookery. The firft account of the method of
preparing it after the Japanefe manner was publithed by

Kempfer,
Beforg

een

‘

_ Method employed to prepare Sty. 343
.. Before I give a'defcription of this method, it, may not be

- improper to ovine the reader that the people im India, in-

ftead of our common kidney beans, cultivate and ufe as
food another fpecies of a fimilar kind, called in botany do-
lichos, and which comprehends feveral fpecies. Among
thefe there is one called dolichos foya. This plant is all over
rough ; and its weak ftem rifes to the height of a man. -Its
flowers, which are {mall, fcarcely appear above the calyx,
and are of a blucifh or almoft violet colour. The rough
hufks contain for the moft part only two feeds, which in
form, fize and tafte differ very little from our garden peafe,
except that they are flatted, fhaped fomewhat like an egg,
and have:a black iaiiia at the place where they begin to
germinate*.

Thefe feeds form the principal component part of foy. Tn
Japan they are firft boiled, and then mixed with the fame
quantity of barley or wheat meal, (the latter is for the pur-
pofe of giving the foy a darker colour) ; and the mixture,

_ being covered up, is depofited for twenty-four hours in a

warm place, where it ferments. Thefame quantity of com-
mon falt, with the like quantity and half as much water, is
thrown over it; and the whole mafs, for the {pace of two
or three months, is ftirred round daily with a chocolate ftick,
and clofely covered immediately after. At the expiration of
that period it is ftraimed or fqueezed through a linen cloth,
and the liquor, which is preferved in wooden veffels, be-
comes always clearer and better the longer it is kept. The
thafs which remains is again fubjefted to a like procefs by
having water poured over it, and, being ftirred round for
fome days, as before, is then ftrained,

* Hilum fufeum. The firft defcription and figure of this plant was given
by Kempfer in his Amcenitat. exot. p. 837, 838. Both thefe, however, |
were improved and rendered more complete by Bergius in Abhandlungen
der Schwedifch. Atad. xxvi. p.281. The lateft defcriptions are thofe of
Thunberg in his Flora Faponica, p, 282; and Jacquin in Collefanea ad
bglanicam et hifi, nat, vol. i. p. 46.

£4 of

344 Method employed to prepare Soy. 3

Of the preparation in China the following account hae
been given by Eckberg, a Swede*: Thirty-five pounds of
thefe beans, clean wafhed, are boiled for a few minutes with
water in a covered veffel, until they can be eafily preffed to-
gether between the fingers. They are then put into a fieve;
and when they are ftill moift, after the water has run off,
they are ftirred round in fine meal, made of the fame beans,
until they are completely covered by it. They are then put
into fmall fieves, or laid upon fmooth mats to the height
of an inch and a half above each other, and are depofited in
a bafket covered with mats, where they are fuffered to remain
three or four days till they begin to grow mouldy. They are
then firft expofed to the air, and afterwards dried in a ftrong
fun-heat, or in a warm place, until-they can bear the ftroke
of a hammer; when they are rubbed between the hands, and
in that manner freed from the meal and mouldinefs with
which they are covered. They are then thrown into earthen -
veffels, and a pickle compofed of 20 pounds of falt and 100
pounds of fpring water is poured over them. Thefe earthen
veffels are expofed open during. the day to the fun, but at
night they are covered ; or they are put in fome warm place,
for the {pace of fix weeks, until their whole fubftance be well
extracted, When it is obferved that the pickle has become
thick and of a dark brown colour, it is poured off, and boiled
feveral times in order to render it thicker. Some, during
-thefe boilings, add to it fugar, ginger and other fpices ac-
cording to pleafure, leaving the whole to ftand for a few
days; after which it is ftrained.

From what has been above faid, it may be readily per-
ceived that the preparation of foy in Europe would be at-
tended with no difficulty if it were poffible to cultivate the
beans. Bergius, however, gives his countrymen little hope
that this can be done; and chiefly for this reafon, that the
plant blows fo late in green-houfes, that the fummer is gone
before the fruit can ripen, But thisis often the cafe with

* Abhandlungen der Schwedifchen Acad. XXVi. P: 40 ;
exotics

Method employed to prepare Soy. 345

exotics which are reared by our gardeners in hot-houfes.
As they only begin to blow when their nourifhment decreafes
and occafions a ftoppage of their growth, the fame thing
may happen too late in too fertile a foil, or when they have
a fuperfluity of nourifhment. On the other hand, when they
are tranfplanted into foil fomewhat poorer, and into an open
place where they have lefs fhelter, they do not grow fo quick

and fo long; but they blow earlier. And hence it happens,

that many exotics planted in the open air produce ripe feeds,

which could never be obtained from them while they were

preferved as curiofities and favourites of the gardener in
green-houfes. I confider it, therefore, as an experiment worth
making, to plant thefe beans in the open fields; and lam
inclined to think that in many fummers they would pro-
duce ripe feeds, efpecially as Jacquin fays i cae that they
throve well at Vienna in the open air. |

Should my conjecture, however, be not “yealifed, this
would not, at any rate, be the cafe with that of Bergius,
who is of opinion that a kind of foy might be obtained from
our peas and beans by the fame or a fimilar procefs ; but in-
deed it would have this great fault, that it would be toa cheap,
and too foon become common.

III. Comparative View of the expanfive Force of the Sicam
of Water and that of Alcobol. By R. Prony. From the
Journal de Ecole Polytechnique.

Tue experiments from which the following tables are
deduced have been deferibed by Bettancourt, their author,
in.amemoir publifhedin1790. I gave the refults of them,
together with a {hort defeription of the apparatus ufed, in the
firft volume of my Architeciure Hydraulique, in treating on
the general theory of the application of {team to the move-
ment of machines; but in’ the fecond volume, which con-
tains a complete defcription of fleam-engines from the firft

7 inventiog

946 On the expanfive Force of the Steam of Water,
imvention of them down to the moft recent’ difcoveriess»f —
- yecur to the labours of Bettancourt, which I have explained
at full length, as well as the application that may be made of
it to phyfics and the arts*. I refer thofe,; who may be de-
firous of being thoroughly acquainted with the fubject, to
that work, and fhall here content myfelf with giving an -
of the apparatus. aig
The fluid with which the experiments, were made was

‘confined in a very ftrong boiler made of copper, being eight
aia at its greateft diameter, and fourteen inches im height.
-Fhe upper part of it was clofed by a cover made of copper
alfo, through which paffed three tubes. The firft ferved to
Jotroduce the fluid into the boiler, and could be clofely thut
by means of a fcrew. The fecond was occupied by a ther-
smometer, havi ing its ball about two inches above the bottom
of the boiler, 8 the feaie, which was on the outfide, con-
tained, from o to E10° of Reaumur.. To the third was .
adapted a bent barometric tube, having two lines of internal
‘diameter, the afcending. branch of which was 110 inches in
Jength.

_.By means of a lateral ecck a communication was efta-
‘plifhed between the boiler and an air pump, which ferved to
make a vacuum before a fire.was kindled in the furnace
below the*apparatus. This circumftance of evaporation im

_ &yacuum, forms an effential. difference between the experi-

‘ments of Bettaneourt and thofe made before by Ziegler, and
renders them applicable to the theory of the fleam-engine,
where the vapour acts in a {pace freed from air,

* In this fecond volume will be found experiments made on the fame
odject, and communicated to me by their author John Henry Ziegler:
They were publifned at Bafle in 1769, in a memorr entitled: Speermer
phyfico-chemicum de digeflore Papini, ejus firufturd, effeét et ufity primi-
tias experimenterum novorum circa fiuidorum & calore rarefadtionem et
‘waporum elaflicitaiem exbibens Bettancourt, who did not fee them till he
had hnifhed his own, mentions them ir his memoir. It will be perceived,
by the account I have given of them, that they deprive him of none of
. that glory which he has g right to expeét from his labours, L

A Vee

heit’s thermometer, Epir.

and that of Alcobol. 347

A vacuum having been made in the boiler, ay mercury
brought as nearly as pofible to a leyel in the two branches
of the barometric tube, and the thermometer reduced to

zero by means of ice, the ice was removed, and a fire was

kindled, which was excited gently and with much equality,

in fuch a manner that the barometer paflfed over about a

degree per minute. One perfon then ftood by to obferve the

barometer, and another to obferve the thermometer, and

each kept a regifter from degree to degree of the preffure
and correfponding temperatures; the preffure being exprefied
by the height in (French) inches of the columns of mercury,
which rofe above the level in the long branch of the baro-
meter,

It was exceedingly difficult to prevent either the introduc-

tion of air into the boiler, or the extravafation of vapour,

according as the internal preffure was lefs or greater than
the weight of the atmofphere: means, however, were found
to obviate thefe inconveniencies; but they are too long to be
detailed here, and muft be read in the works before men~
tioned.

The obfervations of the expanfive force of the fteam of
water furnifh 110 refults, proceeding from degree to degree
of the thermometer, and beginning at zero. Thefe refults
are contained in the annexed table, where the degrees of
preffure are expreffed in (French) inches of mercury, and
the temperatures denoted according to Reaummur’s fcale *.

_ The experiments on the expanfive force of the fteam of
alcohol were made by the fame procefles, and with the
fame apparatus, as thofe employed with the fteam of water.
The object of them, independently of their general utility in
phyfics, was to make known the relative expences which
would be occafioned by thefe fluids, when ufed to produce
moving forces in fleam-engines, This object of refearch is

* For the convenience of our readers, we have added another column te
the table, in which we have given the correfponding degrees of Fahren«

both

348 On the expanfive Force of the Steam of Water, Se.

both important and new. The expence of movement in a
fteam engine is compounded of the price of the fluid evapo-
rated and that of the fuel. The ufe of water requires no
farther expence than that of the fubftance employed as fuel ;
but it is poffible that fome other fluid, much dearer in itfelf,
may neverthelefs have fuch expanfion, that with an equality
of preffure the faving in fuel may be greater than the price
of the fluid. If the refults from the fteam of alcohol be
compared with thofe from the fteam of water, it will be feen
that, at the fame temperature, the expanfive force of the
fteam of the former is always more than double that of the
latter. Much lefs fuel then will be neceflary to produce in
a fteam-engine the fame effect by alcohol; and if the ap-
paratus were difpofed in fuch a manner as not to lofe the
condenfed liquor, which would be attended with no great
difficulty, it might be ufed with much advantage in certain
cafes, and in engines of {mall dimenfions. But, according to.
every appearance, there are other fluids lefs expenfive than
alcoho}, which may have an equal or even a greater expanfion;
and it would be a very ufeful object of refearch to determine
the mechanical effe&t of which fteam is fufceptible, and te
give tables on that fubjeét, fimilar to that here Late “d in
regard to water and alcohol.

The refults given by experiments, of the expanfive force
of the fteam of alcohol at different temperatures, are ex-
preffed in the fame manner in the following table, as thofe
given by the experiments on the fteam of water.

TABLE

[ 349 }

Tusk of the Expanfive Force of the Steam of WarER
and of ALCOHOL.

Temperature.
Reaum. Fahr.
o— 32
I 3425
2— 36,50
So 38775
4— 41,00
Sis, (43925
6 — 45,50
Zo, 47575
8 — 50,50
ees 7152225
IO — 54,50
ert °*56575
Iz — 59,00
13 — 61525
Ig — 63,50
15 — 65,75
16 — 63,00
17 — 70925
18 — 72950
TQ i= ~ 7475
20 = 77:00
25 —— 79225
22 — 81950
23 — 33975
24 — $6300
25 _— 88,25
26 — gi 50
27 == 92375
28 — 95200
29 — 97925
3° — 99950
3L — 101975
32 — 104900
33 — 106.25
34 — 108350
35 — 110975
36 — 11300
37 — 115925
38 — 117950
39 — 119975
“40 — 122,0c
4l — 124,25
42.— 126,50
43 — 128,75
-44 — 131,09
BS — 133925
46 —- 135,50
47 — 137975
48 —. 140,00
49 —— 14225
$9 144959
51 — 146,75
52 — 149,00
53 ~~ 151925
Stet 053950
ao 255975

Preffure.
Water. Alcohol,
0,00 — 0,00
0,00 — 0,00
0,00 — 0;00
0,90 —= 0,05
0,02 — 0,09
0,02 — 0,12
0,505 — 0,18
0,07 — 0525
0,10 06532
O,I2 pn 0535
0,15 viz O45
0,13 — (0,50
B22 es 2.62
Oy27 —— 0,72
0,30). 0,82
9535 — 293
0540 2! F,02
0,45 — 1512
op eget y (Es
0,58 =» 1588
065 — 1,52
975. =) 1565
0392 =. 1480
CpG O15 95
0397 —~ 2,10
1505 —— 2532
TgI2 = 2,52
1922 — 2575
1932 '—=" 2595
1,42 — 3,20
gS e I S340
1,65 — 3,70
1,78 — 4,00
F900" 950
2,00 —= 4,60
2515 — 4,95
23927 ims 8528
2945 — 555
2957 — 6,00
2575 — 6545
2992 — 6,90
3270 == 17535
3927 — 7582
3947 — 8537
3970 — 3,92
3995 — 9548
4925 —- IO,15
4,45 — 10,80
9975 =, 11,50
5,00 — 12,20
5935 a (12935
5370, == 13975.
6,05 — 14,60
6,50 — 15,50
6,90 — 16,40
713% —= 17365

Temperature.
Reaum. Fahr,
56 — 158,00
57 — 100,25
58 —- 162,50
59 — 164575
60 — 167,00
61 — 169,25
62 — 171,5¢
63 — 173375
64 — 176,00
65 — 178,25
66 — 180,50
67 — 182,75
68 —. 185,00
69 — 187,25
72 — 189,50
7t — 191,75
ea ao
73 = 196,25
74 — 193150
DSSS
76 — 203,00
TD 285925
78 — 207,50
LD 9775
80 — 212,00
Br — 214,25
82 — 216,50
83 — 218,75
84 — 221,00
85 — 223,25
“86 — 225,59
87 — 227575
88 — 230,00
89 — 232525
99) = 234359
9t — 23675
92 — 239,00
Cate Sh ee
94 243250
95 ab)
96 — 248,00
roe not es Fe)
g8 — 252950
OO F54075
100 — 257,00
IOL-—~ 259525
102 — 261,50
103 — 263,75
log — 266,00
To5 — 263,25
106 —— 270,50
107 —— *72975
108 — 275,00
109 — 277925
L1Q —= 279,50

Preffure.
Water. Alcohol.
7985 — 18,35
8,40 — 20,00
8,85 —= 21,20
$9535) 22939
9995 s— 24372
10,40 — 24,80
11,00 — 26,10
11,79 — 27,40
12,40 — 23,90
13920 — 30,60
13,30 — 32,00
14,50 —= 33350
159255 ea Sake.
16,10 —~ 37520
16,90 —— 39,49
17,80 — 41530
18,70 — 43,50
19,50 — 46,00
20,60 — 48,10
21375 —= 50,20
22,99 — 52,60
24,15 — 55230
25952 — 57299
26,67 — 61,00
28,00 — 63,80 -
29,60 —= 56,90
31,30 — 69,30
33,00 — 73340
34:60 — 76,30
3645 — 79:60
33,10 — 83,60
40,00 — 87,10
42)20 —_ 90,80
44130 —— 95900
46,40 — 98,00
48,40
550
53290
55930
57280
60,50
63540
66,20
69,00
71,30
75309
78,20
81,00
84,00
86,80
89,00
Oa559
93959
95160
98,90

I aie a
IV. An Analyfis of the Waters of two Mineral Springs dt

Lemington Priors, near Warwick; including Experiments
tending to elucidate the Origin of the Muriatic Acid. By
Wirt1am Lams, M. A. late Fellow of St. Jobn’s Col+
lege, Cambridge. From the Memoirs of the Literary and
Philofophical Society of Manchefter, Vol! V. Part I.

[Concluded from p. 269.]

XI. FURTHER PROPERTIES OF THE OXYGENATED
MURIAT OF IRON.

Tue facts T have related are unqueftionable: it was in
the latter end of 1795 that I firft made the obfervation on thé
effect of hepatifed water upon iron:, fince then I have veri-
fied it repeatedly, and particularly in the month of Decem-
ber 1796, with fome very: pure iron, and in the prefence of
two gentlemen, very competent judges, one of whom affifted
at every part of the procefs. Still it has been afked, How is
it poffible that this folution can contain muriatic acid, feeing
that nitrat of filver, that moft delicate’ teft of this acid, is
hardly affected by it? To this it might perhaps be afufficient
reply, that it is unreafonable to oppofe a mere analogy to
the direct evidence of the fenfes; particularly in a new cafe,
where we have found fome of the analogies beft eftablithed in
chemiftry-to fail. But let us recur once more to experiment.
I formed again fome oxygenated muriat of iron. I fuffered
the acid to remain on the oxyde about 24 hours; then poured
off the liquor, and evaporated the falt to drynefs to expell the
fuperfluous acid: the falt, which deliquefees inftantly on
cooling, was re-diffolved ina little diftilled water. x. I tried
the folution with the acetite of lead: not the fmalleft cloud

was produced. 2. The folution was then tried with the-.
nitrat of filver: a little white curdy matter was formed.
3. A tea-fpoonful of the folution was diffufed through two or
three ounces of diftilled water, and then tried with the nitrat
of filver: avery flight cloud was formed, and a minute purple

precipitate fell, but not till after fome hours, The appear~ -
ance:

¢ * | he Sa Ya eS” 4;

An Analyfis of two Mineral Springs, Se. 35k
ance was not fo ftrong, nor the precipitate fo. copious, as.
when nitrat of filyer is dropped into ordinary rain water.—
Thefe experiments evince, that this falt either does not de-
compofe the falts of lead and filver, or that the new com-
pounds are foluble in water. The firft is abfolutely con~
clufive: as to the fmall appearance of decompofition in
Exp. 2 and 3, be it confidered how difficult it is to prevent a
minute quantity of common acid from pafiing over in the
diftillation of the oxygenated acid; and how readily this acid
itfelf is decompofed: add to this the imperfect oxydation,,
perhaps, of the iron, If thee circumftances are duly weigh-
ed, it feems probable, that this falt, when quite pure, would
not at all fenfibly decompofe nitrat of filver. A flight im-
purity cannot be detected by acetite of lead, a3 a fmall quan-
tity of muriat of lead is foluble in water.

B1II. FURTHER CONSIDERATIONS ON THE HEPA-

TISED SCLUTIONS.

Befides the oxygenated falts, I think it probable, that
thefe folutions retain fome fulphur; but under what form,
or in what combination, it is not eafy to fay. The refiduum,
after evaporation, has a peculiar fmell, whereas the pure
falts are inodorous, The ftain left upon filver by the refi-
duum ought, perhaps, to be attributed to this caufe. Alfo,
the white matter formed by the decompofition of oxygenated
muriat,of mercury feems to be a combination of fulphur
and mercury. In proof of this it may be remarked, that
the precipitate of this falt diffolved in fimple hepatifed wa-_
ter is white. Further, it is doubtlefs true, that if hepatifed
water have a {mall quantity of acid mixed with it, the folu-
tion of iron ftrikes.a purple colour with galls. To point out
the origin, af this colour, mix iron filings and fulphur not
wathed, and form them into a pafte with a little water, and

Jet them. remain together for fome hours: put the pafte in-

to wales, and filtrate: this water now {trikes a purple colour
iit with

45% An Analyfis of two Mineral Springs

with galls. Now, common fulphur is always contaminated
with a little fulphuric acid; and, as neither hepatic gas nor
oxygenated falt is here concerned, the effe&t muft be at-
tributed to the acid and the fulphur. If this water be eva-
porated, it leaves a matter which does not deliquefce; but
which emits the fame {mell as the refiduum of the hepatifed
folutions. To fhew that the acid is neceffary to the pro-
duction of the purple colour, let the fulphur be well wafhed
with diftilled water before it is mixed with the iron; and it
will be found that no fuch colour can be now produced.
The following faé& feems to prove that fulphur may be re-
tained in water, in the form neither of fulphur nor of hepatic
gas: it is an additional proof how effentially the oxygenated
differs from all the common falts of iron. I faturated a di-
luted folution of oxygenated muriat of iron, which fearcely

affected nitrat of filver, with hepatic gas. A white preci=—

pitate fell, but fo minute that it was impoffible to collet it,
nor did it deftroy the tranfparency of the water: hence I
think it probable that, if the falt were quite perfect, it would
not be fenfibly affected by hepatic gas. I now boiled the
liquor, to expell the gas, till it wholly loft its hepatic fmell.
The liquor was again tried with nitrat of filver; and there
was a copious depofition, but of a dark byownifh colour.
It feems certain, then, that fome fulphur is retained by the
folution, which cannot be expelled by boiling.

XIII, THE NEUTRAL SALTS OF THE WATER: MURIAT
- OF MAGNESIA, MURIAT OF SODA, SULPHAT OF
SODA.
A gallon of the water was cv aporated to drynefs ; ; the de-

ieaetoen: falts were feparated from the non- deliquefcent 5
sen each of the falts which were thus obtained was care-

fully examined. Thus, by proceffes which are fufficiently ©

known, it was found that the gallon of water contains of

muriat of magnefia 11.5 grains nearly ; muriat Mes a 430 .

grains; fulphat of foda 152 grains.

The

an

—

et Lemington Pricrs: 45%
The triple compound of which I have treated, is mixed
‘vith the deliquefcent falt of magnefia, but not wholly; for
it may be difcovered with the non-deliquefcent falts, though
thefe have been feparated carefully by fpirit of wme. The
tartrite of potafh indicates it in both. Oxalic acid does the
fame thing, feparating a white powder with fome cryftalline
‘grains which are the oxalat of manganefe. (See Bergman,
Differt. viti. 24.)

XIV. THE RESIDUUM OF DIFFICULT SOLUTION:

After thefe falts had been feparated there remained a large
refiduum, which was not foluble except in a great quantity
of water. This has acryftalline form like fulphat of lime; and
the ufual reagents fhewed it, in fact, to contain both lime and
fulphurie acid. But the weight of this refiduum, from a
galion of water, was no lefs than 112 grains: a larger quan-
tity than could be diffolved in a gallon of water, if it were
pure fulphat of lime. If it be confidered that the water re-
quires fome evaporation before thefe cryftals begin to fepa-
rate, the proportion is {till more increafed. There muft be,
therefore, fomething peculiar in the compofition of the falt,
or in the foluble powers of the water, Other experiments
fhew the fame thing: 1. Sulphuric acid dropped into the
water precipitates copioufly fulphat of lime. This cannot
be effected by the decompofition of the muriat of lime;
fince we have already féen that no fuch falt isto be
found (x1i1.). Indeed it cannot exift in the fame folution
with fulphat of foda, as thefe falts decompofe each other *,
2. Somctimes a more unexpected appearance than this

* Tt is aftonifhing that this fact fhould have been negle&ted, and that in
recent publications. Mr. Schmeiffer, in his analyfis of the waters ofKil-
burn Wells (Phil. Tranfac.), has joined together falphat of foda, fulphati
of magnefia, aod muriat of lime, as being contained in thefe waters. Dr:
Garnett lias alfo put into the cov pofition of the fulphur- well at Harrowgare
fulphat of magnefia and muriat of lime ; an error the more unaccountable,
as Bergman has exprefily remarked this decompofition in his Differtation

Ny _ anthe Analy fis of Waters. See Differt. ii 7. M.

Vo. I, ; Aa takes

354 An Analyfis of two Mineral Springs

takes place. It is, that a precipitate, feemingly like the
former, has been made by the addition of the muriatic acid:
but by the addition of more acid the precipitate is re-dif-
folved.. Sometimes, indeed moft commonly, F have not
been able to effect this appearance.

Tt was natural to expeét the folution of any further un~
common obfervation in the fame matter that had already
explained fo much. 3. I accordingly digefted fulphat of —
lime in the hepatifed fofutions of iron and manganefe; and
I found that the latter had a very ftrong folvent power. Af-
ter the liquor had been filtered, fulphat of lime was plenti-
fully precipitated by fulphurie acid. The folstion of iron
feems to have fomething of a fimilar property; but as it is
very fmall, and as iron has almoft always a little manganefe
united with it, it is at leaft uncertain whether the whole
effect ought not to be attributed to manganefe.

Tt remains to compare this remark with the effe&s of the
artificial oxygenated falts; and thus to confirm, if confirma~+
tion were needed, the analogy which IT have laboured te
eflablifh. 4. Sulphat of lime was digefted with the oxyge-
nated muriat of manganefe and diftilled water by a gentle
heat: after 24 hours the elear liquor was feparated ;. into
this I dropped a little fulphurie acid; by degrees a large
quantity of fulphat of lime was feparated. Muriatic, acid
was dropped into the fame liquor, but it did not feparate any
thing. The oxygenated muriat of iron poffefled the fame
property, but im fo fimall a degree, that here again [ am in-
clined to attribute this power to a little mangancfe attached
‘to the iron. It follows from thefe facts, that the large quan~
tity of fulphat of lime is kept in folutien by the falt of man-
ganefe. And a further examination of the refidaum itfelf
thews that it contains the triple falt of manganefe and iron.
5. Some of the refiduum was perfectly edulcorated, and ful-
phuric acid was dropped upon it; the vapours of muriatic
acid arofe, and were rendered evident by paper moiftened
with ammoniac. or with fimple water. To the fulphurie

sagid,.

/

at Lemington Priors. 355

acid, which was ufed in this experiment, was added fome
diftilled water, and the liquor was filtrated: it was then
faturated with an alkali; a {mall precipitate fell, which was
proved (by the ufual methods) to contain both manganefe
and iron.

6. I have noticed.a variation (2.) in the effect of muriatic
acid when added to the water. * I have obferved a fimilar va-
riety in the refiduum itfelf; which is, that fometimes it has
been found foluble in the muriatic acid: when this happens,
the addition of an alkali precipitates the refiduum in its ori-
ginal cryftalline form; and this it does before the acid is fa-
turated. But moft commonly the muriatic acid does not
diffolve it at all. Further, it has been faid above (vit. 1.)
that the acids precipitate a cryftalline fubftance from oxyge-
nated muriat of iron. This fubftance I have found to con-
tain manganefe. But what belongs to this place to obferve
is, that it is not always, indeed it is but rarely, that this ef-
fe&t can be produced in any great degree: in a very fimall
degree it may always be obferved ; but, when I firft remarked
it, the precipitate was very copious, fo that enough was
readily eolleéted for examination by the blow-pipe. The
falt of manganefe does not fhew this appearance in the -
fmalleft degree. It depends, therefore, on fome peculiarity
of the iron ruft, but precifely on what I cannot take upon
me to determine.

As the oxygenated falts unite with all the other falts of
the water, and confequently cannot be feparated by fpirit of
wine, I have found it impoffible to determine the quantity
of them.

I had concluded from the experiment (1.) that this water
contained muriat of lime; and the following remark con-
dirmed me in myerror: I mention it, as I think it probable
that others have been led into miftakes from the fame caufe.
I reduced fome of the water, by evaporation, to about two
punce-meafures; taking for granted that by this procefs

Aad nearly

356 An Analyfis of two Mineral Springs

nearly the whole of the fulphat of lime was feparated. By
adding fulphuric acid to this hquor, 20 grains of fulphat of
lime were precipitated. I concluded, therefore, that this
muft have proceeded from the decompofition of muriat of
lime: in truth, this fulphat was diffolved in the two ounce+

meafures of water, and was feparated by-the decompofition
ef the oxygenated falt.

ON THE WATER OF THE OLD BATHS.

Tue {pring which fupplies thefe baths was difcovered in
1786, in which year a cold and a warm bath were con-
ftruted. Upon finking the well, a rock was found at the
depth of eighteen feet; and the water rifes from about the
depth of three feet within the rock,

XV... THE GASEOUS FLUIDS.

I could obtain very little gas from this water, not more
than three cubic inches from a gallon. It was azotic. An
hepatic {mell is perceptible when the water is frefh. To the
hepatic gas, doubtlefs, it is owing, that no oxygen is found
in this water or in that of the other fpring. Dr. Garnett
has fo well explained the caufe of this circumftance, that it is
needlefs for me to enter upon it, (See Dr. G. on the Mi-
neral Waters of Harrowgate, p. 74, &c.)

EVI. THE SPONTANEOUS PRECFPITATE:

This water is pellucid when it firft rifes from the fpring ;
in {mall quantities it does not lofe its tranfparency: a very
fmall fediment is depofited by boiling, fo fmall indeed that
fufficient cannot be collected in this way for examination.
However, when the bath has been newly filled, in fome hours

the tranfparency of this large body of water is deftroyed byex-
pofure to the atmofphere, and it contraéts a whitifh colour. I
collected a large quantity of this precipitate from the bottom of
the bath, where it by degrees accumulates. 1. I firft attempted
its analyfis by acids, but was difappointed. It is hardly foluble

in
5

at Lemington Priors, 357

tn any of the mineral acids: they all take up a little of it,
make a brifk effervefcence, and excite heat when firft ap-
plied; but neither by a long digeftion, nor by boiling, could
[faturate the acids; nor, by putting a very fmall quantity of
the powder into a large quantity of acid, could I completely
diffolve the powder.

2. But by the ufe of the blow-pipe it readily appeared
that this fediment is no other than the oxydes of the two
metals fo frequently mentioned, iron and manganefe. It
may be made magnetic; it gives the hyacinthine colour to
borax; the colour is deftroyed by continuing the fufion, and
may be renewed by removing the globule to a filver {poon :
fufed with foda and nitre it makes a blue or a green globule.
As the fediment may be procured in fufficient quantity, I
repeated the laft experiment on a larger fcale: fome nitre
being mixed with it, the mafs was pulverifed, and fufed in a
grucible; when taken out of the fire it was green, and dif-
folved in water, to which alfo it imparted a fine green co-
Jour: in a day or twoa yellow ochre was depofited, when
the folution became blue; from ¢his liquor a powder fub-
fided by expofure to the air, which was manganele. (See
Scheele’s Ef'ay on Mang. xxxvi. B.

3- Purfuing the obfervations of the effets of the mineral
acids confirms this conclufion, I mixed fome of the fedi-
ment with powdered charcoal, and expofed the mixture to a
{trong red heat: it became of a light brown colour, and
now proved to be readily foluble in all the mineral acids.
(See Scheele’s Eflay on Manganefe, xxxviil. A.) With
the muriatic and nitric it formed a gelatinous compound,
The fulphuric acid, diluted, was foon faturated 3; the liquor
was evaporated, and depofited white cryftals, the form of
which is rhomboidal. This is a triple falt, the bafe of
which is iron and manganefe. If there be a fmall excefs of
acid, the tafte is very like that of fulphat of argill. The fame
falt may’ be obtained by boiling the fulphuric acid with the
fediment itfelf, and continuing the boiling till the mafs is be-
Aa3 : come

358°. An Analyjis of two-Mineral Springs

come dry: the falt may then be procured by lixiviating the
dry mafs, and cryftallifing the folution.

XVII.

Neither fulphat of argill nor oxygenated muriat of mer-
cury is at all decompofed by this water.

XVIII. THE METALLIC SALTS,

All the appearances which demonftrate the exiftence of
peculiar metallic falts in the waters of the new baths are alfo
to be found in this: as, the oxydation and folution of metals
and a copious precipitate by galls, while the pruffiat of pot+
ath is not affeéted (1v.): and the fame experiments were
repeated to fhew the prefence of the oxygenated falts of iron
and manganefe (v. vi1. &c.) with the fame refult, and au-
thorife the fame conclufions. Still I believe there is fome
difference in regard to thefe falts between the two waters.
1. [havealready obferved (xvit.) two points of diftinction ;
and, as the fecond of thofe experiments is probably an in-
dication of fulphur, this water feems to he without it. This
is confirmed by evaporating the water in a’ filver veflel, to
which it communicates no ftain. However, 2. Its action
on copper is very ftrong, .fo that, if it be boiled ina copper
veffel for a long time, a blue oxyd of. copper is feparated
from the veifel. But here, again, there is a difference be-
tween this and the former water; for, though copper is dif-
folved in it, none can be precipitated on iron in its metallic
form, as we have feen (rv. 1.). The iron in this water does
not feem to be in that high degree of oxygenation that it is
in the other. This I infer, pebatite 3. the precipitate formed
by tinéture of galls is of a much darker colour, eyen when
the water has been much evaporated; fometimes, when the
water has been reduced to half its original bulk, I have re-
marked even a very flight green tinge communicated by
pruffiat of potafh, Buta not till it has ea added to it many
hours,

As

at Lemington Priors. 359
As the oxygenated faits are formed by the ation of hepa-

‘tic gas. on the metals, it cannot be doubted that they are

very common. Bergman (Differt. vir. 6.) obferyes, ‘that
cold martial waters, when frefh, almoft always have an he-
patic fmell:” it feems very probable then that this falt of
iron may be found in almoft ail fuch waters. 1 doubt not
that it has been, frequently miftaken for muriat of lime, te
which in its properties it approaches very nearly.

Though I have purpofely avoided al! medical difeuffion in
this effay, I cannot abftain from beftowing a moment’s con-

_fideration on one very obvious queftion. What, it will be

afked, are the medical properties of manganefe? Is it ufeful?
{sit mnocent? Is it noxious? That it is innoxieus [| cer-
tainly know. Dr. John Jehnftone (Eflay on Mineral Poi-
fons, page 134.) has fhewn that it may be taken in large
dofes without injury; and he has informed me, that he has
fince confirmed the fame fact frequently. I with I could as
well anfwer the firft queftion; but what the medical virtues
of this fubftance may be, is a fubje& which {till remains in
a great meafure unexplored. It is certainly wel! worth the
attention of men of fceience. To thofe who are inclined to
Jabour in this field I take leave to fuggeft, that they fhould
ufe either the carbonat or fome other falt of manganefe ; the

Dlack oxyde, I apprehend, muft be hardly foluble in the hu-

man fluids.
XIX. THE NEUTRAL SALTS:

Thefe are the fame as of the other water, but in different

quantities. The gallon contains of muriat of magnefia 58 ;

—nmuriat of foda 330 ;—fulphat of foda 62 grains.

XX. THE RESIDUUM.

A ftill larger refiduum is obtained, after the feparation of
the neutral falts, from this than from the other water: The
gallon leaves 146 grains. Its properties are the fame as of
that already defcribed (x1v.).

Aag . it

360 An Analjfis of two Mineral Springs

It is to be obferved, that both thefe fprings are ‘affected by
tainy weather; and that, confequently, their contents vary
confiderably according to the feafons,

SYNOPTICAL TABLE OF SUBSTANCES CONTAINED IN
THE TWO SPRINGS.

Gafeous fluids contained in a wine-gallon in cubic inches. |

WATER OF THENEW WATER OF THEOLD

BATH. BATH.
Hepatic gas - - + | toofmall tobe meafured. | too fmall to be meafured,
.Azoticgas - - = 365 3
Carbonicacid gas - os

Solid contents of a wine-gallon in grains,

Carbonatof iron - - 175
Oxyds of iron and man-

ganefe rhe ‘too fmall to be weighed,
Oxygenated muriat of ;
~ jron and manganefe unknown, but very fmall. unknown, but very fmall.
Sulphur r - = |} unknown, but very fmail. r
Muriat of magnefia - 11.5 58
Muciatof foda - - 430 330
Sulphat offoda - ~ 152 6z
Sulphatoflime - - 112 e E46

Extraét of a letter from Dr. HOLME, dated Sepi. 25th 1797,

** In the analyfis of the waters of the new baths I have
conjectured that the decompofition of oxygenated muriat of
mercury is occafioned by a minute portion of fulphur, at-
tached to fome of the fubftances diffolved in the water (111.). -
I have attempted to verify this gonjedture, and not without

-fuccefs. Withing to colle fome quantity of the precipitate,
I evaporated a gallon of the water to half its bulk; but found,
that now the falt of mercury was diffolved without decompo-
fition, I added, therefore, the falt to the water without
boiling ; and fuffered the precipitate to fubfide. By this
procefs, I could colleét no more than a grain from a galion
gf water. Y threw this upon alkali heated to rednefs; but

% the

at Lemington Priors. 36r

the whole inftantly evaporated with a denfe fmoke, I mixed,
therefore; another portion (procured in the fame manner)
with alkali, and heated them in a crucible: ftill I failed to
colle& any fulphur from the alkali (as I had hoped); but I
now perceived that, as the crucible became hot, the matter
burnt away with a blue flame, as fulphur does.

“ Sulphat of argill is not decompofed by this water when it
has been reduced by evaporation: however, it gradually fe-
parates fome of the abundant fulphat of lime; which is pro-
bably caufed by its attracting the water which held it in
folution.

“J think it right here to obferve, that I have recently met
with this water in fuch a condition that it caufed a perma-
nent decompofition of fulphat of argill. This precipitate is
extremely minute: I have not as yet determined the caufe
of it, but I fufpeét it to be carbonat of magnefia.”

V. Second Memoir on the Metal contained in the Red Lead of -
Siberia. By Cit. Vauguexzin. From the Annales de
Chimie, Vol. X XV. 1798. :

I HAVE already fhewn in my firft memoir * on the

red lead of Siberia, that this mineral ‘contains a parti-

cular metal, which I promifed to examine with more atten-

tion. The Council of Mines having furnifhed me with a

pretty large quantity of the red lead, confidering its fearcity,

I have been able to make a feries of experiments fufficient

to determine its principal properties, of which I fhall now

give an account; but it will firft be neceflary to recapitulate,

- gna few words, the fub{tance of my former memoir, in order

that what I haye to fay at prefent may be rendered more in-

telligible. ; |
1. I fhall obferve, that on boiling the réd lead reduced to
@ powder with two parts of the carbonat of potafh, the lead

* Bee page 279. ;
combined

362 On the Metal contained

eombined itfelf with the acid of the carbonat; and that the
sikali was afterwards united with a particular acid, which
gave it an orange-yellow colour, and the property of produe
ihe eryftals of the fame colour.

. That this new contvbination was decowmpofad by mineral
icc ; and that on caufing the liquor, in which the decom-
pofition had heen effected, to evaporate, there was ebtained,
on the one hand, the falt formed by the mineral acid which
had been added; and on the other, the acid of the red lead,
under the form of elongated priims ef ‘a ruby colour.

3. That the combination of the acid of the red lead with
_potath formed, with the nitrat of mereury, a precipitate of a
cinnabar red colour; with the nitrat of lead, an orange-yel-
low fediment; with the nitrat of copper, a precipitate of a
ehefinut-red, &e.

4. That this acid alone beeame green by the econtaé of
light, by a folution of tin and of the oveater part of metals.

5. That the fame acid, either free or in a flate of combi-
nation, combined itfelf with borax, microcofmie falt, and.
glafs; and communicated to them a beautiful emerald-green
eolour. .

Such, in a few words, are the’ principal properties of the
acid of the new metal contained in the red lead, as an-
founced in roy firft memoir. I fhall now proceed to ex-
amie the other chara¢terifing marks of this fubftanee ; and
fhall enlarge chiefly on thofe which ought to make us con-
fider it as a particular metal, and on thofe which diftinguith
it fram other badies of the fame. ciafs.

Exp. }. Aétion of Acids on the Red Lead.

If one part of the muriatic acid, mixed with as much
wattr, be poured over the red fead, reduced to powder, there
will be formed miuriat of lead, which depofits itfelf under the.
form of white cryftals, and the liquor affumes a very beauti-
ful orange colour.

Tne

in the Red Lead of Siberia, 363
, In this operation the muriatic acid, as is evident, com-
bines with it in virtue of a greater affinity to the lead, from
which it feparates the natural acid, which is then diflolved in
the water of the muriatic acid. When fuitable proportions
of the acid, water, and lead have beememployed, if the liquor
be evaporated by a gentle heat and without the contaéct of
light, you may obtain cryfials of the acid of a ruby red
colour. But if too great a quantity of the acid be ufed,
r an acid too much concentrated; and, above all, if heat
has been employed in the procefs; inftead of a red acid.
you will obtain a dark green liquor, which is then a com-
bination of the oxyde of the new metal with the muri+
atic acid. It will be feen hereafter what are the caufes of
thefe effential differences: at prefent it is fuficient to mene
tion them.

The fulphurie acid decompofes alfo the red lead, by laying
hold of the oxyde; but I did not employ it to extraét the
acid, becaufe, if ever fo little a quantity more than is necef-
fary be added, it is very difficult to feparate it.

The nitric acid does not produce any change in the nature
of the red Jead, only that when aided by the action of heat
it effects its folution; but on cooling, the greater part of the
red lead feparates itfelf with all its properties.

Exp. Il. A&ion of Alkalies on the Red Lead.

Cauftic alkalies do not feem to decompofe the red lead,

for they diffolve it entirely, and form with it a kind of triple
combination; the properties of which I did not examine
minutely.
_ Alkaline carbonats, on the contrary, decompofe the red
lead completely; and there is formed, on the one hand,
carbonat of lead; and on the other, a foluble falt compofed
of the metallic acid and of the bafe of the carbonat em-
ployed.

The falts formed by this acid with alkalies cryftallife into
prifms, or into lamine of a golden yellow colour, the forms

of

364 On the Metal contained °

of which I have not been able to determine accurately, om
account of the {mall quantity I could make.

Thefe falts have a flight metallic tafte: they diffolve with
effervefcence, and aflume a green colour: they are decom-
pofed by acids and alkaline earths, which form orange yellow
precipitates,

Exp. III. tion of Acids on the Acid of the Red Lead, )

Among the mineral acids, the muriatic is the only one
which atts in a remarkable manner on that of the red lead.
Indeed, whether the red lead be diftilled, or its acid with the
muriatic acid a little concentrated, there is foon difengaged
oxygenated muriatic acid, and the liquor affumes a- very
beautiful green colour. The caufe of this may be readily
conceived: the muriatic acid takes from that of the lead a
part of ‘its oxygen, and reduces it to the ftate of a green
oxyde, which is held in folution by another portion of the
muriatic acid.

As this experiment announced to me that the oxygen does
not adhere ftrongly to that metal, [ was defirous to know
whether its acid mixed with the muriatic acid would diffolve
gold: I therefore put into this mixture a piece of gold leaf,
which was diffolved in a little time by the help of a gentle
heat,. and the folution had a yellowifh-green colour. This
acid then produces the fame effect as the nitric acid in aquar
regia, in regard to the folution of gold.

The fulphuric acid, cold, produces no effeét upon this acid}
but when warmed it makes it affume a blucifh green colour,
by favouring, no doubt, the difengagement of a portion of
its oxygen, as it does in regard to the oxyde of manganefe
and the acids of tungften and molybdena.

The fulphurous acid lays hold of a part of the oxygen of
this acid, becomes fulphuric acid, and reduces that of the
lead to the ftate of an oxyde, which it diffolves.

Exp,

im the Red Lead of Siberia. 365

Exe. IV. Reduéiion of the Oxyde of the Red Lead.

An experiment which could. not but excite my curiofity
was, to know whether the acid of the red lead, treated in a
fuitable manner, could be reduced to a metallic flate. For
this purpofe I put 72. parts of this acid, extracted by the
muriatic acid in the manner before mentioned, into a eruci+
ble of charcoal, which I placed in another crucible of earth
filled with charcoal duft. Having then heated it for half an
hour in a forge fire, I found m the charcoal crucible a me-
tallic mafs of a whitifh grey colour, in the form of needles
interwoven through each other, and which weighed 24 parts.
The refult of this operation fhews that the acid of the red

Jead contains a large quantity of oxygen, fince of 72 parts

employed, 24 only, which make one third, were converted
into metal.

Exp. V. Properties of the Metal.

The {mall maffes with which I was obliged to make my
experiments did not allow me to difcover a great number of
properties in this metal. The few, however, which I ob-
ferved are fufficient to characterife it, and to induce me te
affign it a particular place among the metallic fubftances.

1. It is white, greyifh, exceedingly brittle, infufible, fixed
and cryfiallifed into needles.

2. Expofed to the heat of the blow-pipe it becomes covered

with a lilac-coloured cruft, which, on cooling, turns green.
3. Heated by the fame apparatus with borax it. does not
melt; but a part after being oxydated diffolves in that falt,

and communicates to it a very beautiful green colour.
4. The action of acids upon it is exceedingly weak. The
nitric acid is the only one which makes it undergo ‘any re-

markable change. By diftilling five or fix times fucceffively

to drynefs 20 parts of this acid, concentrated, upon one of
the metal, I was able to convert it into an orange yellow

powder, which at firft was green,

This

366 On the Metal contained

This powder is acid; diffolves in water$ combines itfelf”
with alkalies, from which it difengages the carbonic acid
and precipitates metallic folutions, exactly with the fame
phenomena as the acid of the natural red lead. It therefore
appears tome, beyond a doubt, that I have made here, in
every refpect, the particular acid, fuch as it exifts in the red
lead of which it forms one of the elements.

My experiments, and the phenomena they gave rife to, as
mentioned in this memoir, authorife me to confider the fub-
ftance which mineralifes the lead in the red lead of Siberia
not only as a metal, but as a particular metal, which, with
the general properties of the metals already known, poffeffes
very diftinét characterifing marks that belong to no other.
What metallic fubftance, indeed, is there, which, converting
itfelf into an acid of a ruby red colour, has the property, in
that ftate, of becoming green by the light, by caloric and
metallic fubftances, and of precipitating the nitrate of mer-
cury of a cinnabar red colour; lead of an orange yellow
colour ; nitrat of copper of a cheftnut red colour; of diffoly~
ing gold conjointly with the muriatic acid; of precipitating
the tanning principle of a brown colour, and alkaline
pruffiats green ? Without doubt there is none.

On account of thefe properties, and by the advice of
Cit. Fourcroy and Hauy, I propofe to call this metal ehrome,
which fignifies colour; becaufe its combinations are, imdeed,
all more or lefs coloured. I however muft confefs that this
appellation is not fuited to the metal itfelf, fince it has no
particular colour; and that, befides, each metal has one
peculiar to itfelf, more or lefs different. I am not, there-
fore, attached to this name more than to any other that may
be given it, provided it exprefs any of its moft ftriking and
mott characteriflic qualities.

The brittlenefs and infufibility of this metal do not give us
reafon to think that it can be applied to very many ufeful
purpofes; but we may ftill hope that, if it can be found
hereafter in larger quantities, the combinations of its acid

9 with.

an the Red Lead of Siberia. 367
with metallic oxydes, and of its oxyde with vitreous fub-
flances, will furnith very beautiful and durable colours for
the art of painting and enamelling. This hope appears to
me fo much better founded, as I have already difcovered the
oxyde of this metal in the emerald, in which it forms the
colouring principle. 1 have alfo found it in the matrix of
the red lead, in the ftate of a green oxyde combined with
the lead; and I have no doubt that it may be found in
many other combinations, when minerals fhall be examined
avith more care than they have hitherto been.

It refults then that chrome is a peculiar metal before un-
known; that this metal, infufible and cryftallifable, has little
affinity with oxygen, from which it derives however two
thirds of its weight; that this acid of a red colour diflolves
in water and combines with alkalies, earths and metals, to
which it -communicates different colours, but amore or lefs
analogous to its own; that it readily lofes a part of its oxygen
either by light, caloric, or the contact of certain metals, anil

_ the greater part of combuftible fubfiances, by pailing through
all baafe circumftances to the flate of a green oxyde ; and
hence it is that this acid and all its apn teadans yield, by
heat, a certain quantity of oxygen, and communicate to glafs
a beautiful green colour.

Ne

VL. Propofal | for a new Hygrometer. By Mr. HocHHEIMER.
From Economifche Hefte.

Va RiOUS hygrometers have been invented, but they
are all in fome degree imperfect: rfl, becaufe they de not
determine with accuracy in what proportion water is diflolved
in the atmofphere; and adly, becaufe they do not fufler the
moifiure they have imbibed to efcape from them in the fame
proportion as that in which they attracted it. I fhall, there-
‘fore, mention in a brief manner only a few of them, and then
propofe a new method of conftruéting a hygrometer; though
Imuft, at the fame time, remark, that I by no means offer

it

; wat OE,

268 Propofal for a new Hyigrometer.
it as a perfect and complete inftrument. I wifh merely t¢
communicate my ideas on the fubjeét, and to give others ar
opportunity of examining it farther, and of perhaps pro-
ducing fomething that may be better calculated to anfwer the
intended purpofe. It #s, indeed, much to be wifhed, that an
accurate hygrometer could be invented ; as it may be readily
conceived that fuch an inftrument would be of the utmoft uti-
lity, not only to naturalifts, but alfo to farmers and others.
The moft common hygrometer, known under the name of
a weather-houfe, is founded on the property of feveral twifted
fubftances to untwift themfelves in a moift atmofphere, and
then to twift themfelves back when the weather is dry. The
fubftances chiefly employed are cat-gut; and, when required
ona largefcale, hempen ropes. Caffebois, a Benedictine monk,
at Metz, propofed another hygrometer, whieh confifts of the
gut of a filk-worm. When that infect is ready to fpin, there
are found in it two veflels proceeding from the head to the
ftomach, to which they adhere, and then bend towards the
back, where they form a great many folds. The part of thefe
veffels next the ftomach is of a eylindric form, and about a
line in diameter. Thefe veffels contain 4 gummy fort of
matter from which the worm fpins its filk; and, though
they are exceedingly tender, means have been devifed to ex«
tract them from the infeét, and to prepare them for the above
purpofe. When the worm is about to fpin, it is thrown in-
f6 vinegar, and fuffered to remaim.there twenty-four hours;
during which time the vinegar is abforbed into the body of
the infeét, and coagulates its juices. The worm being’then
‘opened, both the veffels, which have now acquired itrength,
are extracted; and, on account of their pliability, are -ca-
‘pable of confiderable extenfion. That they may nat, how-
ever, become too weak, they are ftreiched only to the length
of about fifteen or twenty inches. It is obvious that they
muft be kept fuffitiently extended till they. are completely
dry. Before they attain to that ftate they muft be freed, by
means of the nail of the finger, from a flimy fubftance which
* adheres

Propofal for a new Hygtometer, $69
adheres to them. Such a thread will fuftain a weight of fix
pounds without breaking; and may be ufed for an hygro-
meter in the fame manner as cat-gut. Paper, parchment,
- wood, ivory, hair, and the beard of wild oats, &c. have
: been employed for hygrometers on the fame principle.

Anotlier fort of hygrometer is founded on the increafe of
Weight which certain bodies acquire by the moifture they
attract front the atmofphere. Thus, for example, if a fponge
_ which has been dipped in a folution of fal ammoniac, and
j again dried, be fufpended in the open air at the end of a ba-
lance, the variation of its gravity marked by a weight placed

at the other end will fhew the temperature of the atmofphere
in regard to drought and moifture.

Mr. Lowitz found at Dmitriewfsk in Aftracan, on the banks
of the Wolga, a thin blueifh kind of flate which attracted
moifture remarkably foon, but again fuffered it as foon to

efcape. A plate of this flate weighed, when brought to a red
heat, 175 grains, and, when faturated with water, 247: it
had therefore imbibed, between complete drynefs and the
point of complete moifture, 72 grains of water. Lowitz fuf-
pended a round thin plate of this flate at the end of a very
delicate balance, faftened within a wooden frame, and fuf-
pended at the other arm a chain of filver wire, the end of
which was miade faft to a fliding nut that moved up and
down in a fmall groove on the edge of one fide of the frame.
He determined, by trial, the pofition of the nut when the
* balance was in equilibrio and when it had ten degrees of
i over-weight, and divided the {pace between thefe two points
into ten equal parts, adding fuch a number more of thefe
parts as might be neceflary. When the ftone was fufpended
4 from the one arm of the balance, and at the other a weight
; equal to 175 grains, or the weight of the ftone when per-
feétly dry, the nut in the groove fhewed the excefs of weight
‘im grains when it and the chain were fo adjufted that the
balance ftood in equilibrio. A particular apparatus on the
fame principles as a vernier, applied to the nut, {hewed the
Vout. Bb excels

a; er 2S

pavers?
ee i

470 Propofal for a new Hpgrometers

excefs of weight to ten parts of a grain. Lowitz remarked
that this hygrometer in continued wet weather gave a moif-
ture of more than 55 grains, and in acontinued heat of 113
degrees of Fahrenheit only 14 degree of moifture.

In my opinion, it would not be neceffary, in order to con~
ftruct fuch a hygrometer, to procure argillaceous flate from
Aftracan, as feveral other argillaceous kinds of flate, as well
as ftones and other fubftances, poffefs im an equal degree the
fame property. If a perfon, for example, prefles with the
finger on a marble flab, a grey free-ftone or a piece of glafs,
it will immediately attract the infenfible perfpiration, and
become tarnifhed.

The hygrometer thus invented by Lowitz was however
attended with this fault, that it never threw off the moifture
in the fame degree as the atmofphere became drier. It was
alfo fometimes very deceitful, and announced moifture when
it ought to have indicated that drynefs had again begun to
take place in the atmofphere. To avoid thefe inconveniencies,
I would propofe the following method :

1. Take a fquare bar of {teel about two lines in thicknefs,
and from ten to twelve inches in length, and form it into a
kind of balance, one arm of which ends ina ferew. Onthis.
{crew letthere be {crewed a leaden bullet of a proper weight,
inftead of the common weights that are fufpended.

2. Take a glafs plate about ten inches long and feven inches
in breadth, deftroy its polifh on both fides, free it from alk’
moifture by rubbing it over with warm afhes, fufpend it at
the other end of the balance, and bring the balance into equi-.
librium by fcrewing up or down the leaden bullet.

3. Mark now the place towhich the leaden bullet is brought
by the fcrew, as accurately as poffible, for the point of the
greateft drynefs.

4. Then take away the elafs-plate from the balance, dip
it completely in water, give it a fhake that the drops may
rumofffrom it, and wipe them carefully from the edge.

5. Apply —

|
|
a

Propofal for a new Hygrometer. a4
g. Apply the glafs-plate thus moiftened again to the ba~
lance, and bring the latter into equilibrium by fcrewing the
leaden bullet. ‘Mark then the place at which the bullet
ftands, as the higheft degree of moifture.

6. This apparatus is to be fufpended in a {mall box of
well-dried wood*, fufficiently large to fuffer thé glafs-plate to
move up and down. An opening muft be made in the lid,
exaétly of fuch a fize as to allow the tongue of the balance to
move freely. Parallel to the tongue apply a graduated circle,
divided into a number of degrees at pleafure from the higheft
point of drynefs to the higheft degree of moifture. The box
miuft be pierced with fmall holes on all the four fides, to give
a free paflage to the air; and to prevent moifture from pene-
trating into the wood by rain, when it may be requifite to ex-
pofe it at a window, it muft either be lackered or painted.
To fave it at all times from rain, it may be covered, however,
with a fort of roof fitted to it in the moft convenient manner.

But all thefe external appendages may be improved or al-
_ tered as may be found neceflary,

VII. Method employed in Spain for making the Alcarrazas,
or Veffels ufed there for cooling Water. By Cit. LASTEYRIE.
From the Journal des Mines, No. XXXIV. 1798.

AXLCARRAZAS are a kind of veffels ufed in Spain fot
cooling water intended for drinking. As they are exceed-
ingly porous, the water ooZes through them on all fides;
the air which comes in contaét with it, by making it evapo-
rate, carries off the caloric contained in the water in the
veffel, and by thefe means renders it remarkably cool +.
4 Thefe

* We would recommend a glafs.cafe. Enprr.
4 It is a principle, univerfally admitted, that a liquid, pafling to a
ftate of vapour, appropriates to itfelf a quantity of caloric, which it takes

- from thofe bodies with which it is in contact. The more volatile a liquid

is, the more rapid will be this effect; and it is on this principle that che~
Bba mitts,

402 Method employed in Spain
Thefe veffels, which are of different forms and fizes, are
manufactured in various parts of Spain, and are generally of
a greyith white colour. The moft celebrated place for this
{pecies of pottery, and that from which all the veffels of this
kind ufed at Madrid are brought, is Anduxar in Andalufia.
The earth employed for making them is procured on the
banks of a rivulet called Tamuforo, which is fituatéd at the
diftance of a quarter of a league from the above town.

The ufe of thefe vafes was iitroduced into Spain by the
Arabs. They are fill ufed in Egypt, as well as in different

parts of Africa; and are known in the Eaft Indies, Syria, °

Perfia, China, and other parts of Afia.

It is aftonifhing that thefe vafes were never introduced by
the Arabs into Sicily. I never faw any of them in any
part of that ifland. This fingular fact proves, that the
fimpleft and moft beneficial ufages are rarely imitated by

mifts, during the heats of fummer, caufe, in fome minutes, the congela-
tion of water inclofed in a fimall glafs ball covered with a cloth dipped in
ether, care being taken to renew it in proportion as it evaporates. ° It is
well known that coldnefs may be effeéted by liquors much lefs volatile
than ether, either by expofing the vafe, the furface of which has been
moiftened with them, to a current of air, or by {winging itround a point of
-fufpenfion, which by moving it through the air ferves to favour the folu-
tion of the vapour in the atmofphere. From thefe principles it will be
readily conccived on what depends the property of the alcarrazas above
mentioned. On being expofed to the open air, or rather to a current of
air, the water they contain becomes cool in a little time, and to fuch a
fenfible degree, that tn femmer, when the thermometer ftood at 992 °F.
in the fhade, at Madrid, the water has been known to defcend to the
temperature of water preferved a confiderable time inacellar. Thefe
vafes, however, cannot be long ufed, unlefs care be taken to fill them only
with very pure water, and fuch as is little charged with the fulphat of
lime (jelenite). Turbid water foon clofes up the pores even of filtering
paper; and the fame effeét will be produced by water that helds in folution
fulphat of lime, becaufe the water abandons it in proportion as it unites
with the air in a ftate of vapour. To open the pores, clofed up by earthy
falts, it will be fufficient to keep thefe vafes for fome moments in boiling
water. Epir.
other

“

for making the Alcarrazas. | 373

other nations, unlefs recommended by fome favourable in-
cident.
- Phough France is fo near to Spain, and though there has
: always been great intercourfe between thefe two countries,
no traveller has ever yet given an account of the procefs em-
ployed in the fabrication of the above yafes. The introduc-
- tion of them into France would, in my opinion, be attended
with great advantage; for, befides the pleafure of drinking
cool water during the great heats, we ought to take into
_ -confideration the benefit that would arife from them in
regard to the health. I have, thereforé, procured correét
information refpecting the manner in which thefe vafes are
made in Spain; and I have brought alcarrazas to France, as
__ well as the earth employed in the fabrication of them.
| Cit. Darcet was defirous of analyfing this white marly
earth ; and, by employing all the precifion neceffary for that
purpofe, he found that 100 erains of it contained 60 of cal-
careous earth mixed with alumine and a little oxyd of iron
dificult to be diffolved, and 36% of filiceous earth alfo
mixed with alumine and the fame oxyd*. The quantity
of iron may be eftimated at almoft a grain, The procefs for
fabricating the alcarrazas is very fimple; and, as the earth
_ employed abounds in France, it will be eafy, by the method

which I fhall explain, to eftablith manufaGtories of this
kind; the expences of which will be trifling, and the profits
certain, if the public do not refufe to adopt a ufeful practice.

The preparation given to the earth may be reduced to’
_ three principal operations.

1ff Preparation. Suppofe it were neceffary to manufac-
ture 150 pounds of earth: after it has been dried, and divided
‘to’portions of the fize of a walnut, it is macerated in a
bafon or tub, by proceeding in the following manner: The |

_ *A French journal ftates the refult of Cit. Darcet’s analyfis thus:
€ About one third part of calcareous earth; one third alumiine; one third
?

Cxerinixed with a very fmall portion of iron.” Epgr. ;
Mic, Bb3 workman:

374 Method employed in Spain

workman takes three or four celemins of earth*, which aré.

fpread out equally in the bafon, and water is poured over it 5
he then throws in three or four celemins more of earth,
which are watered as before; and this operation is repeated
until the tub be fufficiently full. In pouring on the laft
water, care is taken not to add more than may be neceflary
to cover the whole mafs. The earth is fuffered to remain in
this flate for twelve hours; after which it is worked and
kneaded with the hands, in the tub, until it is reduced to
the confiftence of a tough pafte. The earth is then de-
pofited on a {moath platform covered with brick, kept ex-
ceedingly clean, and over which is ftrewed a little fifted
afhes. It is formed into a cake about fix inches in thicknefs,
which is fmoothed on the furface as well as at the fides. It is
left in that {tate until it begins to crack ; after which it is
freed from the afhes adhering to it, and removed to another
tiled place made exceedingly clean,

2d Preparation. To this earth the workman adds feven
pounds of fea falt, if he wifhes to make jarras, and only the
half if it is deftined for the fabrication of botifas or cantaros.
This difference arifes from the greater or lefs capacity in-
tended to be given to the vafes, The larger the vafe is, its
fides muft be fo much thicker, in order that it may have the

neceflary degree of ftrength; but the earth, at the fame ,

time, muft be more porous, otherwife the water would not
filter through with eafe; and, for this reafon, the workman
adds a greater quantity of falt when he wifhes to make
garras, which are much larger than the oti/as and cantaros,
The earth is kneaded with the feet, adding the falt gradually;
and this labour is repeated, at leaft three times, without the
neceflity of adding more water, as the moifture retained by
the earth is fufficient.

3d Preparation. The earth, after being fubjeéted to thefe
different preparations, is fit to be applied to the lath. The

* The celemin is a meafure of capacity, which contains about feven |

pounds of grain,

may

) for making the Alcarrazas. ° 375
man who is employed for this work ought to knead it well
with his hands, taking care to extract the flones, even the
q ‘*, fmalleft which he may meet with, as well as every other
. foreign body. He then forms it into lumps, which he ap-

- plies to the lath to be made into vafes or jars.
The alcarrazas may be baked in any kind of furnace ufed

an
Mf

by potters. Thofe employed in Spain are eighteen feet
{quare in the infide; and five feet three inches in height.
The flame enters by a hole, one foot four inches in diameter,
fituated in the centre. Such a furnace will contain 800
pieces of different fizes, including 500 jarras. Poitery of
much greater f{trength than the alcarrazas may be baked in
the fame furnace, if care be taken to keep up the fire for one
or two hours longer. The alcarrazas, which require to be
only half baked, remain there ten or twelve hours, according
to the température of the air, or the greater or lefs quantity
of fuel employed.
Procefles different from that which I have here defcribed,
are purfued in fome of the potteries in Spain; but they all
_ depend on the fame principles. After the earth has been
pounded, it is fuffered to macerate in a tub for twenty-four
hours; the whole is ftirred round with a ftick, and it is
freed from the ftraws or other foreign bodies that float on
the furface. The ftones and coarfer parts of the earth fall to
the bottom of the veffel, and the finer is drawn off by a hole
ur inches above it.~ The earth is then left to dry to a certain
S... requifite; and it is afterwards depofited in a monit

‘
“
n

‘A
A

#

place, to be employed as may be found neceflary. In other
manufactories, the earth, when dry, is ground below a roller;
after which it is fifted, and, the proper quantity of falt and
water being added, it is then kneaded. The proportion of .
falt is not every where the fame. In fome places the fame
quantity of earth requires a half lefs of falt. Care is always
taken to choofe earth of a proper quality, without ever
having occafion to add to it a mixture of fand. The fame
garth is employed -alfo for common pottery; the only dif-

Bb4 ferenes¢

376 Theory of Cryftallifation,
ference is, that falt is added to the clay ufed for the alcarrazas,
and that they are only half baked. : Oe

There is not a fingle family in Madrid where thefe veffels
are not ufed. They are filled with water, which is expofed
for feveral hours to a current of air, in order that the evapo-
ration may be more rapid, and that the water confequently
may become cooler.

A kind of red veffels called ducaros, employed likewife ta
cool water, are made alfo at a place called Salvatierra in
Eftramadura; but the earth being lefs porous, it is not fo
proper for the intended purpofe. Befides, thefe vafes com-
municate to the water a difagreeable argillaceous tafte,
They are, however, in great requeft among the ladies of
Madrid; fome of whom pound fragments of them, and mix
the powder with {nuff. Young girls have a particular fond-
nefs for this kind of pottery, and eat it when they are
troubled with the chlorofis.

Vafes of a fimilar kind to thofe above defcribed, are em-
ployed in Portugal for moiftening fnuff. They are plunged
into water, after being filled with this article; and the
water which filters infenfibly through them communicates

to it, at the end of fome hours, the neceflary degree of
humidity,

VIII. On.the Theory of the Stru€ture of Cryftals, by the Able
Havr, From Vol, XVII. of the Annales de Chimie,

[Concluded from p. 303.]

I. Number of primitive Forms.

Iw the examples before mentioned I have chofen a paral-
jelopipedon for nucleus, on account of the fimplicity of its —
form, Ihave hitherto found that all the primitive forms
may be reduced to fix, viz. the parallelopipedon, in general,
which comprehends the cube, the rhomboid, and all the

folids

Theory of Cry/tallifation, 377
folids terminated by fix faces parallel two and two; the
regular tetraedron; the o¢taedron with triangular faces; the
hexagonal prifm; the dodecaedron with rhomboidal planes ;
and the dodecaedron with ifofceles triangular planes.

Among. thefe forms, there are fome found as nucleus,
‘which have the meafure of their angles different in different
kinds of minerals. This will appear lefs furprifing when
we confider that thefe nuclei are compofed in the firft in-+
ftance of elementary molecule, and that it is poffible the
fame form of nucleus may be produced in one kind by ele-
ments of a certain nature, and in another kind by different
elements; as we fee integral molecule, fome cubic and
others tetraedral, produce fimilar fecondary forms, in confe~
quence of different Jaws of decrement. Bat, it is worthy
of remark, that all the forms, hitherto met with as nuclei,
in the different fpecies, are among the number of thofe
which have a particular chara¢ter of perfection and re-
gulartty, as the cube, the regular o¢taedron, the regular
tetraedron, and the dodecaedron with equal and fimilar rhom-
bufes for its planes. Thefe forms are a fort of limits at
which nature arrives by different routes, while each of the
forms, placed between thefe limits, feems to be attached tg
one unique kind, at leaft as far as can be judged by the
prefent ftate of our knowledge on this fubje, ;

IV. Forms of the integral Molecule,

The primitive form is that obtained by feétions made on
all the fimilar parts of the fecondary cryftal; and thefe fec~
tions, continued parallel to themfelves, conduct to a determi-
nation of the form of the integral molecule, of which the
whole cryftal is an affemblage. This requires certain con~-
fiderations that relate to the moft delicate point of the theory,

which I fhall now explain, with as much precifion as the
_ narrow limits to which I am obliged to confine myfelf will
allow,

There

378 “ Pheiry of Cryftalli ifation.

There is no cryftal from which a nucleus in the form bes 4
parallelopipedon may not be extraéted, if we confine our-

felves to fix fe€tions parallel two and two. “In a multitude ~

of fubftances this parallelopipedon is the laft term of the
mechanical divifion, and confequently the, real nucleus.
But there are certain minerals where this parallelopipedon is
divifible, as well as the reft of the cryftal, by farther fections
made in the different directions of the faces; and there
thence neceffarily refults a new folid, which will be the
nucleus, if all the parts of the fecondary cryftal, fuper-
‘added to this nucleus, are fimilarly fituated. When the
mechanical divifion conduéts to a parallelopipedon, divifible
only by feétions parallel to its fix faces, the molecule are
parallelopipedons fimilar to the nucleus; but, in all other
cafes, their form differs from that of the nucleus, This [
fhall illuftrate by an example.

Let achsno (fig. Go.) bea cube, hit two of its folid
angles a, s, fituated on the fame vertical line. This line will
be the axis of the cube; and the points ¢ and s will be its
fummits. Suppofe this cube to be divifible by feétions, each

_ of which, fuch as a4, pafles through one of the fummits
a, and by two oblique diagonals a4, am, contiguous to this
fummit.- This fection will detach the folid angle z; and as

there are fix folid angles, fituated laterally, viz, 2, b, 6,97, 0,7)

the fix feCtions will produce an acute rhomboid, the fummits
of which will be confounded with thofe of the cube. Figure
61 reprefents this rhomboid exifting in the eube, in fuch a
manner that its fix lateral folid angles 6, d, f, p, g, e, cor
refpond to the middle of the faces achi, crsh, bins, &c.
of the cube. But geometry fhews that_each of the angles,
at the fummits bag, dsf, psf, &c. of the acute rhom-
boid, are equal to 60°, from which it follows that the lateral
angles cbf, agf, &c. are equal to 120 degrees.
Befides, it 1s proved by theory, that the cube refults from
a decrement which takes place bya fingle range of {mall
rhomboids,

Theory of Cryftallifation. 379

thomboids, fimilar, to the acute rhomboid, on the fix ob-
lique ridges ab, ag, ae, § d, sf, sp. This decrement pro-
duces two faces, one on each fide of each of thefe ridges, which
makes in all twelve faces. But as the two faces; which have
the fame ridge for their line of departure, areon the fame
plane by the nature of the decrement, the twelve faces will
be reduced to fix, which are fquares ; fo that the fecondary
folid is a cube. This refult is analogous to that of the very

obtufe calcareous fpar before mentioned,
Let us now fuppofe that the cube (fig. 60.) admits, in
-regard to its fummits a, s, two new divifions fimilar to the
preceding fix, that is to fay, one of which paffes through
the points c, 2,0, and the other through the points 4, 7, 7
The firft will pafs alfo through the points 4, gy é and the
, fecond through the points d, f, p, (fig. 61 and 62.) of the
rhomboid; from which it follows, that thefe two divifions
will detach each a regular tetraedron bage or dsfp (fig: 62-)s
fo that the rhomboid will be found converted into a regular
eétaedron ef (fig. 63-), which will be the real nucleus of
the cube; fince it is produced by divifions fimilarly made,
in regard to the eight folid angles of the cube. co
If we fappofe the fame cube to be divifible, throughout its

whole extent, by feétions analogous to the preceding, it is
clear that each of the fmall rhomboids of which it is the af,
___. femblage, will be found, in like manner, fubdivided into an
ogtaedron, with two regular tetraedra applied on the two op-
pofite faces of the o¢taedron.

By taking the oGtaedron for nucleus, we may conftruc& -
around this nucleus a cube by regular fubtractions of {mall
complete rhomboids. For example, if we fuppofe decre-
ments by a fingle range of thefe rhomboids, having 4 for
their point of departure, and madein a direétion parallel to
the inferior edges gf, eg, 2¢ df, of the four triangles,
which unite to form the folid angle 4, there will refult four
' faces, which will be found on a level, and, like the oGtaedron
with fix folid angles, fimilar decrements around the other

five

380 - Theory of Cryftallifation:

five angles will produce twenty faces, which, taken four
and four, will be equally on a level, which will make, im
the whole, fix diftinct faces; fituated as thofe of the eube
(fig. 60.); fo that the refult will be precifely the fame as in. -
fhe cafe of the rhomboid confidered as nucleus.

In whatever manner we proceed to -fubdivide either the
cube, the rhombus, or the octaedron, we fhall always have
folids of two forms, that is to fay, oGtaedra and tetraedra,
without ever being able to reduce the refult of the divifion to’
unity. But the molecule of a eryftal being neceffarily fimi-
Jar, it appeared to me probable that the ftructure was as it’
were interfperfed with a multitude of fmall vacuities, occu-
pied either by the water of cryfiallifation or by fome other
fubftance; fo that, if it were poflible to carry the divifion to
its limits, one of the two kinds of folids in queftion would:
difappear, and the whole cry{tal would be found compofed
only of moléculz of the other form.

This idea is the more admiffible, as each oftaedron being
enveloped by eight tetraedra, and each tetraedron being’
equally enveloped by four o¢taedra, whichever of the forms
we imagine to be fupprefled, the folids that remain will join
exadtly by their edges; fo that, in this refpect, there will be
continuity and uniformity throughout the whole extent of

‘the mafs. The manner in which each o€taedron is enve-
loped by eight tetraedra may be readily conceived, if we take
gare that in dividing the cube (fig. 60.) only by the fix fec-
tions given by the rhombus, we may depart at pleafure from
any two, a2, s; 0, b; c, 2; 7,7, of the eight folid angles,
provided that thefe two angles be oppofite to each other. But
if we depart from the angles a, s, the rhomboid will have
the. pofition {hewn jig. 62. On the other hand, if we de-

. part from the folid angles 0, 4, thefe angles will become the

fummits of a new rhomboid (fg, 64.) compofed of the fame
oétaedron as that of fig- 63, with two new tetraedra applied
on ihe faces bd f, egp (fig. 64.), which were unoceupied
on the rhomboid of fg. 62. Figures 65 and 66 reprefent,
9 one

| Theory of Cryftallifation. 381

ice: the cafe in which the two tetraedra repofe on the faces
dbe, fgp, of the oftaedron; the other, that in which
they would reft on the faces bfg, dep. It is thence feen,
that whatever may be the two folid angles of the cube af-
fumed for the points of departure, we. fhail always have the
fame oCtaedron, with two tetraedra contiguous by their fum-
mits to the two folid angles in queftion; and as there are
eicht of thefe folid angles, the central octaedron will be cir-
cumfcribed by eight tetraedra, which will reft on its faces.
The fame effect will take place if we continue the divifion
always parallel to the firft fections. Each face of the’ oc-
taedron, then, however fmall we may fuppofe that o¢taedron
to be, adheres to a face of the tetraedron, and reciprocally.
Each tetraedron then is enveloped by four octaedra.

The firu@ture I have here explained is that of {parry fluor.
By dividing a cube of this fub{tance we may, at pleafure, ex-
tra&t rhomboids, having the angles formed by their planes
equal to 120° or regular oétaedra; or tetraedra, equally re-
gular. There are a {mall-number of other fubftances, fuch
as rock cryftal *, carbonate of lead (f{parry lead), &c. which
being mechanically divided beyond the term at which we
fhould have a rhomboid or parallelopipedon, give. alfo' parts
~ of various different forms afforted. together in a manner even
more complex thanin fparry fluor. Thefe mixt ftruétures
neceflarily occafion uncertainty refpecting the real figure of
the integral molecule which belong to the fubfances in quef-
tion. I have, however, obferved that the tetraedron is al-
ways one of thofe folids which concur to the formation of
{mall rhomboids or parallelopipedons that would be drawn
from the cryftal by a firft divifion. On the other hand, there
are fubftances, which, being divided in all poffible directions,
refolve themfelves only into tetraedra. Of this number are
garnet, blend, and tourmaline. I fhall foon give examples
_ Of this refult of the mechanical divifion.

* Mémoires de !’Acad. des Sciences, An 5786, p. 78°
In

. 382 Theory of Cryflallifation:

In fhort, feveral minerals are divifible into right trian-
gular prifms. Such as the apatite; the primitive form of
which is a regular right hexaedral prifm, divifible parallel to
its bafes and its planes, from which neceffarily refult right
prifms with three planes, as may be feen by infpecting
Jig. 68, which reprefents one of the bafes of the hexaedrat
prifm divided into fmall equilateral triangles, which are the
bafes of fo many molecule, and which, being taken two and
two, form quadrilateral prifms with rhombufes for their bafes.

By adopting then the tetraedron in the doubtful cafe of
which I have fpoken, we fhould reduce, in general, all the
forms of integral moleculz to three, remarkable by their fim-
plicity; viz. the parallelopipedon, the fimpleft of all the fo-
lids which have faces parallel two and two; the triangular
prifm, the fimpleft of all prifms, and the tetraedron, which 1s
the fimpleft of pyramids. This fimplicity may furmifh a
reafon for the preference given to the tetraedron in {parry
fluor, and the other fubftances of which I have fpoken. I
fhall, however, forbear deciding on this fubject, as the want
of accurate and precife obfervations leaves to theory nothing
but conjectures and probabilities.

But the effential object is, that the different forms to which
the mixt ftructures in queftion conduc, are afforted in fuch
a manner, that their affemblage is equivalent to a fum. of
fmall parallelopipedons, as we have feen to be the cafe in
regard to fparry fluor; and that the laminz of fuperpofition,
applied on the nucleus, decreafe by fubtractions of one or
more ranges of thefe parallelopipedons; fo that the bafis of
the theory exifts independently of the choice which might
be made of any of the forms obtained by the mechanical di-
vifion.

_ By the help of this refult, the decrements to which cryftals
are fubject, whatever be their primitive forms, are found
‘brought back to thofe which take place in fubftances where
this form, as well as that of the molecule, are indivifible

paral~

ee

Theory of Cryftallifation. — - 383
aie, 2 : and theory has the advantage of being able
to generalife its object, by connecting with one faét that mul-
-titude of facts which by their diverfity feem to be little fuf-
_ ceptible of concurring in a. common point.

What has been here faid will be better illuftrated by a
few examples of the manner in which we may reduce to the
theory of the parallelopipedon that of the forms different
from thatfolid.

Cryftals, the molecule of which are tetraedra with i/ofceles
triangular faces.

Garnet.

1. Primitive garnet (fig. 68.) Grenat 2 douze faces. Dau-
benton Tab. Miner. edit. 1792, p.5. Grenat dodeca>dre 2 plans
rhombes. De V'ifle Cry/fallographie, tom. ii. p. 322. var. ¥.

Geomet. chara&. Refpective inclination of any two of the
faces of the dodecaedron 120°. Angles of the rhombus
CLGH,*€ or’ G.=.199° 28! 167;;L or H.= 98° 31! 44%

Though garnets of the primitive form be in general vi-
treous on the fractures, there are perceived on them, how-
ever, laminz fituated parallel to the rhombufes which com- .

pole their furface. Let us fuppofe the dodecaedron divided
in the direction of its lamine, and, for the greater fimplicity,
let us make the feCtions pafs through the centre. One of
thefe fetions, viz. that which will be parallel to the two
thombufes DLFN, BHOR, will concur with a hexagon
which would pafs through the points E, C, G, P, I, A, by
making the tour of the eryftal. A fecond fection parallel ta
the two rhombufes GLFP, BEAR, will coincide with
another hexagon fhewn by the points D, C,H, O, 1, N. If
the divifion be continued parallel to the other eight rhom-
bufes, taken two and two, we fhall find that the planes of
the feStions will be confounded with four new hexagons ana-_
logous to the preceding. But by refuming all thefe hexa-
gons it is feen that their fides correfpond, fome of them with
; the

ee,

484 Theory of Cryftallifations *,

the fmall diagonals of the rhombufes of the —

beast Os:
é

decdedrort,

viz. thofe which would be drawn from C to G, from A to_

I, from C to B, &c. and others would correfpond with the
different ridges EC, GP, Pl, EA, &e.

1. The planes then of the fections paffing through the
fides and through the {mall diagonals of the twelve rhom-
bufes will fubdivide the whole furface into 24 ifofceles tri-

angles, which will be the halves of thefe rhombufes. 2. Since -

the planes of the fections pafs alfo through the centre of the
cryftal, they will detach 24 pyramids with three faces, the
bales of which, if we choofe, will be the external triangles
that ‘make apart of the furface of the dodecaedron, and of
which the fummits will be united in the centre.

Moreover, if we take, for example, the fix tetraedra which
have for external faces the halves of the three thombufes
CEDL, CLGH, CEBH, thefe fix tetraedra will form
a rhomboid reprefented by fig. 69, and in which the three
inferior rhombufese DL GS, GHBS, DEBS, refult
from three divifions which pafs, one through the hexagon
DLGORA (fig. 68.); the fecond through the hexagon
GHBANF, and the third through the hexagon BEDFPO.
Fig. 69 reprefents alfo the two tetraedra, the bafes of which
make part of the rhombus CLGH. One of thefe is marked

by the letters L, C, G, S, and the other by the letters H, C,

G,S. By applying what has been faid to the other nine
rhombufes, which are united three and three around the
points F, A, H (fig. 69.), we fhall have three new rhom-
boids; from which it follows, that the 24 tetraedra, con-
fidered fix and fix, form four rhomboids; fo that the dode-
eaedron may be conceived as being itfelf immediately com-
pofed of thefe four rhomboids, and in the laft analyfis of 24
tetraedra.

I thall here obferve, that the dodecaedron having eight folid
angles, each formed by three planes, we might have confi-
dered them as being the affemblage of the four rhomboids,
which would have for exterior fummits the four angles

G,

Theory of Cryftallifaiions 98s
G, B, BD, A; from which it refults that any one of the
faces, fuch as CLGO, is common to two rhomboids, one

of which would have its fummit in C, and the other in G,

and which would themfelves have a common part in the in-
terior of the cryftal.

~ It may be farther remarked, that a line GS (fig. 69.),
drawn from any one G (fig. 68.) of the folid angles com-
pofed of three planes, as far as the centre of the dodecaedron,
is, at the fame time, the axis of the rhomboid, which would
have its fummit in G, and one of the edges of that which
would have its fummit in C (fig. 68 and 69.). The com-
pofing rhomboids then have this property, that their axis is
equal to the fide of the rhombus. With a little attention it
will be eafily feen, that in each tetraedron, fuch as CLGS
(fiz. 69.), all the faces are equal and fimilar ifofceles tri-
angles.

If we fhould continue the divifion of the dodecaedron by
feCtions paffing between thofe which we have fuppofed to be
directed towards the centre, and which fhould he parallel to
them, we fhould obtain tetraedra always fmaller, and ar-
ranged in fuch a manner, that, taking them in groupes of
fix, they would. form rhomboids of a bulk proportioned to
their own.

The tetraedra, which would be the term of the divifion,
were it poffible for us to reach it, ought to be confidered as
the real molecule of the garnet. But we fhall fee, that, in
the paffage to the fecondary forms, the lamine of fuperpo-

fition, which envelop the nucleus, really decreafe by ranges

of fmall rhomboids, each of which is the affemblage of fix

of thefe tetraedra.

-. - The fulphure of zinc or blend has the fame ftruéture as

the garnet. I have divided by very clean fe&tions fragments

' of this fubftance, in fuch a manner as to obtain fucceffively

the dodecaedron, the rhomboid, and the tetraedron.

Vor. I. Ce q. Tra-

486 Theory of Cryftallifation.

2. Trapezoidal Garnet (Fig. 70.). ie

Gtenat 2 24. faces. Daubenton Tab. Miner. edit. 17
p. 5. Grenat 2 24 facettes trapizoidales. De VIfle Cry
tallograpbhie, tom. it. p. 327.

Geomet. charaé: Refpective inclination of the trape-
zoids united three and three around the fame folid angle
D, C, G, &c. 146° 26! 33";, of the trapezoids united four
and four around the fame folid angle w, a, r, &c. 131° 48! 36".
Anglesofany oneofthetrapezoids m D uw L, L = 78° 27! 46";
D = 117° 2! 8’; mor u = 82° 15/3". The value of the
angle L is the fame as that of the acute angle of the nucleus
of calcareous {par.

This variety refults from a feries of kansas decreafing at
the four edges, on all the faces of the primitive dodecaedron.
For the more fimplicity, let us firft confider the effect of this
decrement in regard to the rhombus CLGH (fig. 68.).
We have juft feen that this rhombus was fuppofed to belong
in common to two rhomboids, which fhould have for fuim-
mits, one, the point C, and the other, the point G. Let us

fuppofe that the lamine applied on this rhombus decreafe
towards their four edges by fubtractions of a fingle range of
{mall rhomboids, in fuch a manner that, in regard to the
two edges CL, CH, circumftances are the faa as if the
rhombus belonged to the rhomboid which has its fummit i ink
C; and that, in regard to the other two edges GL, GH,
the effect is the fame as if the rhombus belonged to the
rhomboid having its fummit in G. This difpofition is ad-
miffible here, in confequence of the particular ftruéture of
the dodecaedron, which permits us to obtain fmall rhom- ,
boids, fome of which haye their faces parallel to the faces of
that with its fummit in C, and the reft io that having its
fummuit inG*, ‘iit his:

* Theory has conduéted me to another refult, which is, that the fum
‘of the nucleus and lamine of fuperpofition, taken together in preportion
a as

Theory of Cryftallifation. 387

érefults of the four decrements being: thus*perfectly

to each other, the laminz of fuperpofition, applied on

ombus C L GH, and on each of the other rhombufes.

of the dodecaedron, will form as many right quadrangular
pyramids, which will have for bafes thefe fame rhombufes.
In fig. 71 may be feen the pyramids which reft on the three
trhombufes CLDE, CE BH, CGH:B (fg. 68.), and
which have for fummits the points m, e, s (fig. 71.); but
on account of the decrement by a fimple range, the adjacent

triangular faces, fuch as EmC, Es C of the two pyramids
that belong to the rhombufes CLDE, CEBH, are on a
level, and form a quadrilateral Em Cs. But we had twelve.
pyramids, and confequently forty-eight triangles. » Dividing
by two, we {hall then have twenty-four quadrilaterals, which
will compofe the furface of the fecondary cryftal. But be-
-caufe the rhomboidal bafes of the two pyramids extend more,
in proceeding from L to E or from H to E, than in proceed- _
ing from D to C or from B to C, the fides mE, Es of the
quadrilateral will be longer than the fides Cm, Cs. More-
over, we {hall evidently have mE equal to Es, and Cm
equal to Cs. The quadrilaterals will then be trapezoids,
which will have their fides equal two and two. :

I am acquainted with no cryftalline form where the ftrie,
when they exift, point out, in a more fenfible manner than
‘m this, the mechanifm of the ftru@ure. We may here
fee the feries of decreafing rhombufes which form each of the
pyramids CLDEm, CEBHs, &c. (fig. 71.), and fome-
| times the furrows are fo deep that they produce a kind of
ftair, the fteps of which have a more particular polifh and
brilliancy than thofe of their facets, which are parallel to the |
ces CEDL, CHBE, &c. of the nucleus,

latter are applied one upon the other, is always equal to a fum of
omboids; though at firft view it does not appear that this fhould be the
cafe, according to the figure of thefe lamine, which reprefent rifing pyra-
ds. See Memoires de l’ Acad. 1789, p. 525.

Cea &

388 - “‘Fbeory of Cryftallifation.

If the decrements ftop abruptly at a certain term, fot
the pyramids are not terminated, the twenty-four see
zoids will be reduced to elongated hexagons, which will
tercept twelve rhombufes parallel to the faces of the nucleus.
This is the variety to which I aig given the name-of inter-

mediary garnet..

In the fulphure of zinc dhe! regular otaedron refults from
a decrement by a range around the eight folid angles, com-
pofed of three planes, viz. C, B, O, G, F,D, A, I (fg. 68.).
The fame fubftamce affumes alfo the figure of a regular te-
traedron, by the help of a decrement by one range on four —
only of the eight folid angles before mentioned, fuch as
C, 0, F, A. This tetraedron is remarkable by its ftructure, °
which prefents an affemblage of other tetraedra with ifofeeles:
faces. - |

Cryftals the Molecule of which are triangular Prifms.

Orientai.

I give this appellation to a kind of gem known under the i
names of the ruby, /upphire, oriental topaz, according as it ©
is red, blue or yellow. It is fo rare to find cryftals of this
gem which do not exhibit marks of a precipitate formation, ©
or which have not been rolled, that hitherto we have had no }
accurate defcription of its different varieties, nor any precife_

indication of the nature of the particular angles of each vam
riety. The cryftals which enabled me to eftabhith the fol<
lowing refults were of a form fufficiently well characterifed. —
i. Primitive Oriental. |
It cryftallifes in the form of a regular hexaedral prifm aig
vifible parallel to its bafes. Theory points out other j joinings,
parallel to the planes, from which it follows, that the mole
cula is an equilateral triangular prifm. The height of thi
prifm, fuch as given by theoretic calculation, is a little lefi
than three times the height of the triangle of the bafe.
Xe Elox

Theory of Cryftallifation., 389

2. Elongated Oriental (fig. 72).
De V’Ifle Cry/fallographie, tom. ii. p. 215. A.

PGeomet. charad. Refpeétive inclinations of the triangles
TA S, IBS, 139° 54’. Angles of the triangle 1 AS,
A = 22° 54!, 1 orS= 78° 48’.

This form is the effect of a decrement by a fimple range of
{mall quadrangular prifms on all the edges of the bafes of the
nucleus. Let gd (fig. 67.) be the fuperior bafe, fubdi-
vided into {mall triangles, which reprefent the analogous
bafes of fo many molecule. The edges of the lamine of
fuperpofition will correfpond: fucceffively to the hexagons
bilmnr, ehuxyv, &c.3 from which it evidently follows,
that the fubtraGtions take place, as I have faid, by ranges of
{mall parallelopipedons or quadrangular prifms, compofed
each of two triangular prifms.

3. Minor Oriental.

Geomet. chara&t. Dodecaedron formed of two right pyra-
anids lefs elongated than thofe of the preceding variety. The
triangles which correfpond to TAS, IBS, are inclined to
each other 122° 36’. In each of thefe triangles the angle of
the fummit is 31°, and each of the angles at the bafe is
74° 30". ‘

The Jaw from which this variety refults differs from that

which produces the preceding, as it determines a mixed
_ decrement by three ranges in breadth and two ranges in’

4 height.

4. Enneagonal Oriental (fig. 73-)-

Geomet. chara@., Inclination of each {mall triangle, fuch

~ as cqitorthe adjacent bafe aciplb ged, 122° 18.

| It is the clongated oriental the {ummits of which are’

replaced by two faces, parallel to the bafes’ of the nucleus,’

with the addition of fix fmall ifofceles triangles gz, /bf,

wzm, &c. the three fuperior of which are alternate in po-

fition with the three inferior. Thefe triangles refult from aj _

decrement by three ranges of {mall quadrangular prifms on
Cce3 the

890 Theory of Cryftallifation. gi
the three angles of the fuperior bafe of the nucleus, fuch as 4,
yt Jig. 67.), andon the intermediate angles of the inferior
. bafe. It may be readily conceived, that in the decrement
which takes place, for example, on the angle g, the three
ranges, which remain unoccupied’ between that angle and
the correfponding edge of the firft lamina of fuperpofition, are,
1ft, the fmall rhombus go7z, which alone forms the firft
range; 2d, the two rhombufes os ti, pxdz; 3d, the three
rhombufes fituated on the fame line behind the two pre-
ceding. :

Cryftals of the oriental are found particularly in the king
dom of Pegu. There are alfo in France fapphires called the
fapphires of Puy. They are found at the diftance of a league
from Velai, on the banks of a rivulet near the village of
Expailly, where they are mixed with garnets and hyacinths,
Thefe fapphires have all the characters of the ftone called
oriental fapphire,

V. Differehce between Struture and Increment.

Tn what I have hitherto faid refpecting the decrements to
which the lamine of fuperpofition are fubjeted, my only
view was to unfold the laws of ftruGture ; and I am far from
believing that, in the formation of a dodecaedral cryftal, or
one of any other form having a cube for nucleus, the cryf-
tallifation has originally produced that nucleus fuch as it is
- extracted from the dodecaedron, and made it afterwards pafs
to the figure of that dodecaedron, by the fucceffive appl-
cation of all the lJaminz of fuperpofition by which it is co-
vered. On the contrary, it feems proved, that from the firft
moment the cryftal is already a very {mall dodecaedron, con-
taining a cubical nucleus proportioned to its fmall fize, and
that the cryftal afterwards increafes by degrees without
changing its form, by new layers which envelop it on all
fides, fo that the nucleus increafes alfo, always preferving
* the fame relation with the whole dodecaedron,

Let

\

Theory of Cryftallifution: 395
Let ug make this more ftriking by an example taken from.
a plane figure. What I am going to obferve refpecting this
fiure may be eafily applied to a folid, fince we may always
conceive a plane firure as a fe&tion of a folid. Let ERFN
then (jig. 74.) be an aflortment of fmall fquares, in which
the fquare AB c D, compofed of forty-nine partial fquares,
reprefents a feétion of the nucleus, and the extreme {quares
R, S, G, A, 1, L, &c. that of the kind of ftair formed by
the laminz of fuperpofition. It may.be readily conceived
that the affortment began by the fquare ABCD; and that
different files of fmall fquares were afterwards applied on
each of the fides of the central fquare, for example, on the
fide A B, firft the five fquares comprehended between I and M,
next the three fquares comprehended between L and O, and
then the fquare E. This increment correfponds with that
Which would take place if the dodecaedron began by being
a cube, proportioned to its bulk, and which increafed af-
terwards by the addition of continually decreafing lamine,
But, on the other hand, we may conceive that the affort-
ment was at firft like that reprefented by fig. 76, in which
the fquare abcdis compofed of only nine molecule, and
bears upon each of its fides only one fquare ¢, 7, f, or 73
and that afterwards, by means of the application of new
{quares, arranged around the former, the affortment has
become that of figure 75, where the central fquare a’ b! ct d’
is formed of twenty-five fmall fquares, and bears on each

_ of its fides a file of three fquares, plus 9 terminating {quare

e, 2, f' or’, and that, in fhort, by a farther application

the aflortment of fig. 75 is converted into that of fig. 74,

Thefe different tranfitions will give an jdea of the manner in
which fecondary eryftals may augment in bulk, yet retain
their form; from which it is feen that the ftruéture 1s com-

bined with that augmentation of bulk, fo that the law, ac-

cording to which ‘all the laminze applicd in the nucleus of
the cryftal, when arrived at its greatett dimenfigns, fucceflively

Cc4 decrgafe,

392 Theory of Cryftalli 5 fathom: Ree:
decreafe, 1 in departing from this nucleus, exifted sean
the rifing cryftal. ee

“The theory I have explained, fimilar in this to ee e)
theories, fets out from a principal. fa, on which it makes,
all faéts of the fame kind to depend, and which are, only as.
it were corollaries. This faét is the decrement of the laminz
fuperadded to the primitive form; and it is by bringing,
back this decrement to fintple and regular laws, fufceptible
of accurate calculation, that theory arrives at refults the
truth of which is proved by the mechanical, divifion of.
* eryftals, and by obfervation of their angles. But there ftill
remain new refearches to be made, in order to afcend a few
fteps farther towards the primitive laws to which the Creator
has fubjected cryftallifation; and which are nothing: elfe
themfelves than the immediate effects of his fupreme will,
~The object of one of thefe refearches would be to explain
how thefe {mall polyedra, which are, as it were, the rudi-
ments of cryftals of a fenfible bulk, reprefent fometimes the
primitive form, without any modification; fometimes a
fecondary form produced in virtue of a law of decrement ;
and to determine the circumftances which produce decre-
ments on the edges, and thofe which give rife to decrements ;
on the angles. I have already paid attention to the folution
of this problem, as delicate as it is interefting; but hithertg
I have only had conjectures, which, before they deferve to
be publifhed, require to be verified by more attentive laboup
and more profound meditation,

TX. On

_

“Ap 303.)

er od Py
YX. On the Principles of Equilibrium, and the Stability of

floating Bodies applied to River and Canal Boats of dif-
_ferent Forms. By Mr, Joun Grorceé EnGLisx, Teacher

of Mathematics and Mechanical Philofophy. Communicated
by the Author,

at HE principles of dynamies in general, and of ftatics in
particular, have already been fo fully explained by fome of
the ableft mathematicians in Europe, that little or nothing
of confequence is farther to be expected on thofe fubjeds,
unlefs our mode of calculus be either greatly improved or
totally changed. And as neither of thefe events is likely
foon to take place, we ought certainly, in the mean time, to
apply to the common concerns of life the principles of which
we are already in poffeffion. But fince war and merchandilé
feem at prefent to be the chief bufinefs of all European
- nations, and fince neither the one nor:the other can be
carried on to any great extent without navigation, nor can
any veffel with fafety be navigated without a proper degree
. of itability; it is therefore a matter of the greateft im-
portance to determine with accuracy the ftability of
nautical veffels of all kinds.

“However operofe and difficult the neceffary calculations,
may in fome cafes become before the degree of this effential
quality can be obtained, yet they all:depend upon the four
following fimple and obvious theorems, accompanied with
other well known ftereometrical and ftatical principles.

‘Tuzorem I. Every floating body difplaces a quantity of
the fluid in which it floats, equal to its own weight: and
confequently, the fpecific gravity of the fluid will be to that,
of the floating body, as the magnitude of the whole is ta.
that of the part immerfed.

THEOREM II, Every floating body is impelled downward,
by its own effential power, acting in the ‘direction of. a,
yertical line pafling through the centre of gravity of the,

; whole ;

$94 Mode of calculating the

whole; and is impelled upward by the re-action of the
fluid which fupports it, acting in the direétion of a vertical
line paffing through the centre of gravity of the part im-
merfed : aaciors: unlefs thefe two lines are coincident, the’
floating body thus impelled muft revolve round’ an aXlsy
either in motion or at reit, until the equilibrium is reftored.

THeorem III. If by any power whatever a veffel be
deflected from an upright pofition, the perpendicular diftance
between two vertical lines paffing through the centres of
gravity of the whole, and of the part immerfed refpectively,
will be as the flability of the veffel, and which will be pofitive,
nothing, or negative, according as the metacentre is above,
coincident with, or below, the centre of gravity of the veffel,

THEOREM IV. The common centre of gravity of any
fyftem of bodies being given’ in pofition, if any one of
thefe bodies be moved froin one part of the fyflem to
another, the correfponding motion of the common centre of
gravity, eftimated in any given direction, will be to that of
the aforefaid body, eftimated in the fame direction, as the
weight of the body moved is to that of the whole fyftem.

From whence it is evident, that in order to afcertain the
ftability of any yeflel, the pofition of the centres of gravity of
the whole, and of the part immerfed muft be determined; with
which, and the dimenfions of the veffel, the line of floatation,
and anole of deflection, the ftability or power either to right
itfelf or overturn may be found.

In fhips of war and merchandife, the calculations necef-
fary for this purpofe become unavoidably very operofe and
troublefome ; but they may be much facilitated by the experi-
mental method pointed out in the New Tranfactions of the
Swedith Academy of Sciences, firft quarter of the ycar 1787;
page 43.

In niver and canal boats, the regularity and fiaiplidfty of
the form of the veffel itfelf, tooether with the compact dif-
pofition and homogeneal quality of the burden, render that
method for them unncceflary, and niake the requifite caleu-

latloas

Stability of River and Canal Bonts. 395

lations become very eafy.. Veflels of this kind are generally
of the fame tranfverfe fection throughout their whole leneth,
except a {mall part in prow and ftern, formed by feoments
of circles or other fimple curves; therefore a length may
eafily be affigned fuch, that any of the tranfverfe feQions

. being multiplied thereby, the produé will be equal to the

whole folidity of the veffel. The form of the fection
ABCD is for the moft part either re@angular as in fig. 1.

* (Plate XTII.), trapezoidal as in fig. 2: or mixtilineal as in

Jig. 3. in all which MM reprefents the line of floatation
when upright, and EF that when inclined at any angle
M XE; alfo G reprefents the centre of gravity of the whole
veffel, and R that of the part immerfed, :
If the veflel be loaded quite up to the line AB, and the
{pecific gravity of the boat and burden be the fame, then the
point G is fimply the centre of gravity of the fetion ABCD;
but if not, the centres of gravity of the boat and burden
muft be found feparately, and reduced to one by the com-
mon method, namely, by dividing the fum of the momenta
by the fum of weights, or areas, which in this cafe are as
the weights. The point R is always the centre of gravity
of the fection MMCD, which, if confifting of different
figures, muft alfo be found by dividing. the fum of the
momenta by the fum of thé weights as common. Thefe
two points being found, the next thing neceffary is to de-
termine the area of the two equal triangles MXE, MXF, _

their centres of eravity 0, 0, and the perpendicular projected’
diftance 2 7 of thefe points on the water line EF. This
being done, through R and parallel to EF draw RT =a
fourth proportional to the whole area MMCD, either
triangle MXE or MXF, and the diftance n 2; through
T, and at right angles to RT or EF, draw TS meeting
the vertical axis of thé veflel in S the metacentre; alfe
through the points G, B, and parallel to ST, draw NGW
and BV; moreover through S, and parallel to EF, draw
WSYV meeting the two former in V and W; then SW is
3s

396: ‘Mode of calculating: the
as the ftability of the veflel, which avill be pofitive, nothing,

or negative, according as the point S is above, coincident,
with, or below, the point G. If now we fuppofe W to ress
prefent the weight of the whole veffel and burden (which,
will be equal to the feétion MMCD multiplied by the
length of the veffel), and P to reprefent the required weight
applied at the gunwale B to fuftain the veflel at the given:
angle of inclination; we fhall always have this proportign :
as VS: SW :: W: P; which proportion is general,
whether SW be pofitive or negative; it muft only in the
latter cafe be fuppofed to at upward to prevent an overturn.
In the rectangular veflel, of given weight and dimenfions,
the whole procefs is fo evident, that any farther explanation
would be unneceflary. In the trapezoidal veffel, after
having found the points G and R, let AD, BC be pro-
duced until they meet in K. Then fince the two fections
MMCD, EFDC are equal, the two triangles MMK,
EFK are alfo equal; and therefore the rectangle EK x
KF=KMxKM=KM7’; and fince the angle of incli-
nation is fuppofed to be known, the angles at E and -F are
given. Confequenily, if a mean proportional be found
between the fines of the angles at E and F, we fhall have
the following. proportions :

As the mean proportional thus found: fine LE :: KM: KF,
And as the faid mean proportional: fine 2 F :: KM: KE;
therefore ME, MF become known; from whence the area
of either triangle MXE or M MF, the diftance 2m, and)

all the other requifites may be found,
In the mixtilineal feCtion, let AB = 9 feet = 108 inches,
the whole depth = 6 feet = 72 inches, and the altitude of
MM the line of floatation 4 feet or 48 inches; alfo Jet the
two curvilinear parts be circular quadrants of 2 feet, or 24
inches radius each. Then the area of the two quadrants =
go4:7808 {quare inches, and the diftance of their centres of
gravity from the bottem = 138177 inches very nearly; alfo
the

ee eS CLC

Stability of River and Canal Boats. 397
the area of the included reftangle abie = 1440 fquare
inches, and the altitude of its centre of gravity 12 inches;
in like manner the area of the reCtangle ABcd will be
found = 5184 fquare inches, and the altitude of its centre
of gravity 48 inches; therefore we fhall have

Momentum of the 2 quadrants = 904°7808 x 13°8177 = 12301798968016

Momentum of the reétan. adie =1440" x12 = 17280"
Momentum of the reftan. ABcd= 5 184° x 48 ==248832°
7528°7808 275613 °98y66016

Now the fum of the momenta divided by the fum of the

ay 3 278613'98966016 ;
areas will give aaa ssoe eT = 37°006 inches, m3 al.
titude of G the centre of gravity of the fection ABCD
above the bottom. In like manner the altitude of R the
centre of gravity of the fection MMCD will be found to

123093" ee

be equal aaaeinte = 24°934 inches; and confe-
3

quently their cane, or the value of GR = 12°072

inches, will be found. if

Suppofe the veffel to heel 15°, oat we fhall have the fol-
lowing proportion, namely, As radius : tangent of 15° :: MX
= 54inches : 14°469 inches = ME or MF; and -confe-
quently the area of either triangle MXE or MXF =
390°663 fquare inches. Therefore, by theorem 4th, As
49306°7808 : 390°663 2:72 = mm = [AB : 5°6975 inches
=RT; and again, As radius : fine of 15° :: 12-072 = GR:
3°1245 inches = RN ; confequently RT—RN = 5°6975—
3°1245 = 2°543 inches = S W the ftability required.

Moreover, As the fine of 15°: radius :: 5°6975 = RT:
22013 =RS, to which if we add 24°934, the altitude of
the point R, we fhall have 46-947 for the height of the
metacentre, which taken from 72, the whole altitude, there
remains 25°053; from which and the half width = 54
inches, the diftance BS is found = 59°529 inches very

4 nearly,

393 Method of purifying Molaffs.
nearly, and the angle SBV = 80°—06’—42!’; from whence
SV = 58'645 inches.

Again: Let us fuppofe the mean length of the veffel to be
40 feet, or 480 inches, and we fhall have the weight of the
whole veffel equal to the area of the fection MMCD =
4936°7808 multiplied by 480 = 2369654°784 cubic inches
ef water, which weighs exactly 85708 pounds avoirdu—
poife, allowing the cubic foot to weigh 62°5 pounds. |

-And, finally, as SV: SW (i.e) as 58°645 : 2°573
85708 : 3760+, the weight on the gunwale which will
fuftain the veffel at the given inclination. Therefore a veffel
of the above dimenfions, and weighing 38 tons, 5 cwts.
23 Ibs. will require a weight of 1 ton, 13 cwts. 64]bs. to
make her incline 15°.

In this example the defleing power has been fuppofed
to act perpendicularly on the gunwale at B; but if the
veffel is navigated by fails, the centre velique mutt be found ; |
with which, and the angle of deflection, the projeéted dif
tance thereof on the line SV may be obtained; and then
the power, calculated as above, neceflary to be apphed at
the projected point, will be that part of the wind’s force ©
which caufes the veflel to heel. And converfely, if the
weight and dimenfions of the veffel, the area and altitude
of the fails, the direction and velocity of the wind be given,
the anele of deflection may be found.

X. New Method of freeing Molaffes from their fbarp
Tafte, and rendering them fit to be ufed infiead of Sugar.
From Crell’s Chemical Annals, 1798, Vol. I. Part 2.

Capet Devaux, according to the experiments made
by Lowitz, gives. the following method: Take twenty-four
pounds of molaffes, twenty-four pounds of water, and fix
pounds of charcoal coarfely pulverifed; and having mixed
shen in a kettle, boil the whole over a flow wood fire.

9 When

1
fi

Defeription' of a Dynanometer. 499
When the mixture has boiled half an hour, pour it into a
flat veffel, in order that the charcoal may fubfide to the’
bottom; then pour off the liquid, and place it over the fire
once more, that the fuperfluous water may evaporate, and
to give to the molaffes their former confiftence. T wenty-
four pounds of molaffes will produce twenty-four pounds of
fyrup.

_ This method has heen employed on a large feale with the
happieft effects ; the molaffes become fenfibly milder, and
gan be employed in many articles of food; though in difhes
where milk is ufed, or for cordials mixed with f{pices, fugar
is to be preferred.

XI. Defcription and Uje of the Dynanometer, or Inflrument
for afcertaining the relative Strength of Men and Animals.
Invented by Cit. Regnzer. From Journal de VEcole
Polytechnique, Vol. I. 6th Year.

Wu EN Sanétorius invented his balance, he: taught
us what we lofe by infenfible perfpiration; and no one,
without this difcovery, would perhaps ever have imagined °
that the matter thrown out from the body is more than half
what we receive as nourifhment. Knowledge no lefs im-
portant might be acquired, had we the eafy means of afcer-
taining, in.a comparative manner, our relative ftrengths at
the different periods of life, and in different ftates of health;
Buffon and Gueneau, who had fome excellent ideas on this
_ fabject, requefted me to endeayour to invent a portable ma-
chine, which, by an eafy and fimple mechanifm, might

conduct to a folution of this quefiion, on which they were
then engaged. Thefe philofophers were acquainted with that
Anvented by Graham, and improved by Dr. Defaguliers, at
London; but this machine, conftructed of wooden-work,
was too bulky and heavy to be portable; and, befides, to
“make experiments on the different, parts of the body, feveral
és _ ‘Machines

re ¥ ys os Fae ean
| nes

400 _ Defeription and Ufe .

machines were neceffary, each fuited to the part required to
be tried. They were acquainted alfo with the dynanometer _
of Cit. Leroy of the Academy of Sciences at Paris. It
confifted of a metal tube ten or twelve inches in length,
placed vertically on a foot like that of a candleftick, and
containing in the infide a fpiral fpring, having above it -a
graduated fhank terminating in a globe. This fhank, toge-
ther with the fpring, funk into the tube in proportion to
the weight Ging upon it, and thus pointed out, in degrees,
the ftrength of the perfon who preffed on the ball with hig
hand.

This inftrument, though ingenious, did not appear fuffi-
cient however to Buffon and Gueneau; for they wifhed not
merely to afcertain the mufcular force of a finger or hand,
but to eftimate that of each limb feparately, and of all the
parts of the body. I fhall not here give an account of the
attempts I made to fulfil the wifhes of thefe two philo-
fophers, but only obferve, that in the courfe of my experi-
ments I had reafon to be convinced that the conftruétion of
the inftrument was not fo eafy as might have been expeéted.
Befides the ufe which an enlightened naturalift may make

* of this machine, it may be poffible to apply it to many
other important purpofes. For example, it may be em-
ployed with advantage to determine the firength of draught
eattle ; and, above all, to try that of horfes, and com-
pare it with the ftrength of other animals. It may ferve
to make known how far the affiftance of well-conftruét-
ed wheels. may favour the movement of a carriage, and
what is its vis inertize in proportion to the load. Wemight
appreciate by it, alfo, what refiftance the flope of a moun-
tain oppofes to a carriage, and be able to judge whether a
carriage is fufficiently loaded in proportion to the number
of horfes that are to be yoked to it. In the arts, ii may be
applied to machines of which we with to afcertain the re-
fiftance, and when we are defirous to calculate the moying
force that ought to be adapted to.them, It may ferve, allo,

as

of the Dyrianiometars his
és a Romian balance to weigh burdens. | In’ fhort; nothing
would, be more eafy than to convert :t into an anemometer,
to difcover the abfolute force of the wind, by fitting to it a
frame of a deterriiined fize filled up with Link aR ; and
it would not, be impofhible to afcertain by this machine the
recoil of fire-arms, and confequently the firength of gun-
powder.

This se iebe ig in its form and fize, Has a near refem-s
blance to a common graphometer. It confifts of a fpring
twelve inches in length, bent into the form of an ellipfiss
from the middle of which arifes a femicircular piece of brafs,
having engraved upon it the different degrees that exprefs
the force of the power acting on the fpring. The whole of
this machine, which weighs only two pounds anda half, op-
‘pofes, however, more refiftance than may be ne¢eflary to de-
termine the action of the ftrongeft and moft robuft horfe.
The fimplicity of its mechanifm will be better illufirated by
the following defcription :

A, an sliitiaakle {pring feen in perfpeCtive, covered with
leather, that it may not hurt the fingers when ftrongly preffed
on with the hands, (/ze Plate XJ.) ° This fpring is coms
pofed of the beft fteel well welded and tempered, and:after-
wards fubjected to a ftronger proof than is indicated by its
graduation, in order that it may not lofe any of its elafticity
by ufe.

B, a piece of fteel ftrongt; faftened to the fpring by means
of a claw and ferews, in order to fupport a femicircular
plate of brafs C, mounted on the fpring, feen geometrically.
On this plate are engraved two ares, one divided into my-
riagrammes, and the other into kylogrammes. Each of thefe
arcs is ftill farther divided by points, which exprefs the
weight in pounds de marc; and all thefe degrees having
been exactly valued by accurate weights, it thence refults
that all; dynanometers of this kind may be compared with

Vou. I. Dd D, a

402 ‘ Defeription and Ufe .
8S fmall fteel fupport, adjufted like the former to thé
other branch of the fpring, and having a cleft towar :
upper extremity to receive freely a fmall copper lev
which is kept in its place by a {mall fteel pin 2. The w
of this mechani{m is feen of its full fize at H.

F, a fteel index, very light and elaftic, fixed upon its axis
by a {crew in the centre of the brafs femicircle. This index
has a final! bit of leather or cloth glued upon the {mall cir-
cular part G, in order to render the friétion on the plate
eafy, uniform, and almoft infenfible. It is to be obferved,
that this index is terminated by a double point, adapted to
the divifions on both the femicircular ares. The firft, di-
vided into myriogrammes and points, exprefling ten pounds
de marc, ferves for all experiments which oblige the {pring
to be elongated in the direction of its greater axis, as is the

cafe in trying the ftrength of the reins, in a word, for all
trials where it is neceflary to draw the fpring by the two
ends. The fecond, divided into kylogrammes and points,
exprefling pounds de marc, is deftined for experiments which
comprefs the twa fides of the fpring, as in trying the force
of the hands.

J, afmall plate of brafs which covers the mechanifm,
to prevent it from being injured. This fmall plate has on it
alfo a divided are, the degrees of which correfpond with thofe
of the firft are of the machine; and by the play of a {mall
mdex 6, which is under the plate, the movements of the
fpring may be afcertained.

K, an aperture in the covering plate, through which may
be introduced a {mall turnfcrew, for the purpofe of tighten-
ing or eafing the index as may be neceflary.

L, ‘a pallet of brafs, with a ferew, having a cap like that .
on the needle of the marinér’s compafs, in which the lower
pivot of the lever, that pufhes round the index or handle, is:
made to play. This pallet, acting asa fpring, yields to any
fudden fhock, and prevents the derangement of the mechanifm.

M, 2

of the Dynanometer. 403
M, a focket riveted on the plate J, in’ which the upper

of the leverturns. ~
; , N,N, fmall cylindric pillars that fupport the covering

te, which is fixed to them by three fcrews.

O, an iron rack, on the lower part of which the feet. cad
be placed when it is intended to try the ftrength of a per-
fon’s body.

P, a double handle of wood, with an iron hook, to be
held at the fame time in the two hands.

Q, a double hook made of iron, one end of which is to
be hooked to the end of the {fpring, and the other to a rope
faftened to a ftake, as at c, when experiments are to be made
on the ftrength of horfes, or others, that require the dyna-
nometer to be fupported by hooks.

R, the manner of holding the dynanometer to afcertain
the ftrength of the hands.

S, pofition of a man when trying the ftrength of his
reins,

T, difpofition of the dynanometer to try the ftrength of
a horfe or any other draught animal. —

The effeéts of this machine may'be thus explained: If a
perfon preffes'on the fpring with the hands, or draws it out
lengthwife, by pulling the two extremities in a contrary di-
rection, the two fides of the fpring approach each other;
and in proportion as they are brought nearer, the {mall
lever of the mechanifm pufhes before it the index, which,
by the tightnefs with which it is ferewed in its place,
will remain at the point to which it has been brought by
the pin d, in confequence of the force aéting on the fpring.

The mufcular force of the arms, or rather the ftrength of
the hands, may be tried by laying hold of the two fides
of the fpring neareft to the centre, as may be feen figure
R; fo that the arms may be a little ftretched, and inclined

downwards, almoft at an angle of 45 degrees. This pofi-
tion, which appears the moft natural, is alfo the moft con-
venient for a man to act with his full force, It is to be.

Ddz recollected,

404 Defeription and Up, Bo
recollected, that the lower arc of divifion, divided in
‘grammes, is that which ferves to exprefs the force o
hands, and of all the ations which prefs the two
of the fpring. The firength of the hands may alfo be tr:
one after the other; and if an account be kept of the de-
gree of preffure of the right hand, and then of the left, and.
thefe two fums be added together, it will be found’ that the-
fum-total is, in general, equal to the ftrength ef both the

hands when acting together. .
To try the ftrength of the body, or rather the rems, the
perfon muft place his feet on the bottom part of the rack O;
one of the ends of the fpring is then to be placed in one of
the hooks of the rack; and the hook P is to be put inte
the other end. In this pofition the body is perpendicular ;
the fhoulders only being inclined a little forwards, to be
able, in throwing back the body, to pull the fpring with
all the force which a perfon is capable of exerting. In this
ii raife a great weight
without being expofed to thofe accidents which might be
occafioned by an effort made in a more conftrained pofition, ~

fituation, reprefented by S, a man m

Nothing can be more convenient than this dynanometer
to afcertain and compare the ftrength of horfes and that of
all draught animals. Figure T fhews, in a fufficient man- ©
ner, the difpofitions neceffary for experiments of that kind.

- The trials I made on this fubjeét are not extenfive ; but as
they were conduéted with care, they may ferve to give a very
jut idea of the abfolute force of horfes of middling ftrength.
For this purpofe I employed four horfes of middle fize, in
good health and well-conditioned, which were fubjeéted fe-
parately and in fucceffion to the fame trial. The firft drew
equivalent to 36 myriagrammes; the fecond 38;; the third
26:3 and the fourth 43. The fum of all thefe is 144 my-
rlacrammes ; and if we take the mean of this fum, we
fhall have, for the ftrength of ordinary horfes, 36 myria-

- grammes, or 736 pounds de marc.

v4 XH. Mer

eee

. Method of filling up Engraving on Silver ‘With a
ble Black Enamel, as pradifed in Perfia and India.
Communicated in a Letter from Siberia to Profeffor PALLAS.
From Neue Nordifche Beytrage, Vol. V.

] AM now acquainted sith the fecret of our filverfmiths
for filling up the engraving in plate with a black, glaffy, -
durable mafs, refpecting which we have fo often converfeds
‘and it is Very fingular that the Ruffians muft have derived
this procefs from the Perfians and the Indians. puove

They take half an ounce of filver, 24 ounces of copper,
3° ounces of lead, 12 ounces of fulphur, and 2+ ounces of
falammoniac. The metals are melted together and poured
into a crucible, which has been before filled with pulverifed
falphur made into a pafte by means of water; the crucible is
then immediately covered that the fulphur may not take fire,
and this regulus is calcined over a fmelting fire until the
fuperfluous fulphur be burnt away. This reoulus is then
coarfely pounded, and, with a folution of fal ammoniac,
formed into a pafte, which is rubbed into the engraving on
filver plate. The filver is then wiped clean, and fuffered to
become fo hot under the muffle, that the fubftance rubbed
into the ftrokes of the engraving melts and adheres to the
metal. The filver is afterwards wetted with the folution of
fal ammoniac, and again placed under the muffle till it
becomes red hot. The engraved furface may then be
fmoothed and polifhed without any danger of the. black
fubftance, which is an artificial kind of filver ore ( fablerz),
_ éither dropping out or decaying. In this manner 1s all the

filver plate brought from Ruffia ornamented with black en-
* graved figures, &c,

Dd3 XIII. Dif-

[ 406 ]

XIN. Different Methods employed in Encauftic Painting, ats
cording to the Principle followed by the ancient Greek and
Roman Painters, difcovered by the Abbé REQUENO, ane

fince praBifed with much Succe/s at Rome. Communi-.
cated by Mr. CoarnLtes Heatucotre TATHAM, Ar-
chitect, bi

Tur following receipt for painting in encau/fo, copied
from an original paper, was prefented to Mr. Tatham, at
Caferta near Naples, by Mr. Philip Hackert, painter to his
Neapolitan Majefty. It exemplifies the mode fuppofed to
be practifed by the ancients in their arabefque. After this
manner a large bath was decorated in a cafino of the king of
Naples at Belvidere near Caferta, the walls and vaulted
cieling of which were entirely covered with encaufto, under
the direction of Mr. Hackert, who was fo obliging as to
accompany Mr. Tatham to vifit the fuccefs of it, which he
did, much to his fatisfattion, when upon his travels in the
year 1795. Beat

The firft preparation is as follows: Infufe a pound of gum
tragacanth * in a proportionate quantity of water, for twen-
ty-four hours, in an earthen yeffel. When this folution is
pretty. thick, add to it mineral colours of any fort, broke
into pieces without being pounded, and which muft after-
wards be prepared in the following manner ;

Put an ounce of white wax and an ounce of gum
tragacanth into a {mall earthen yeflel well glazed, toge-
ther with two or three pounds of water, and keep the vef-
fel over a brifk fire, that the ingredients may become li-
quid, ftirring them continually with a {mall ftick. When
the whole are well diffolved, take the veffel from the fire,
and, after the liquor has cooled, fkim off the wax from
the furface. The oily parts of this wax are left in the
gum water, which muft be afterwards ftrained through a
piece of linen cloth, This liquid and the colours prepared

* Commonly called gum dragon,

with

Methods employed in Encau/flic Painting. 407
with it may be kept feveral months, in bottles clofely ftop-
ped, after a little brandy or fpirit of wine is added to it, and
will be good even at the end of feveral years.

The colours moiftened with the folution of gum traga-
eanth muft, for the greater convenience, be ground with
pure water, and afterwards with the above-mentioned pre-
paration, till they become exceedingly fine ; and they may
then be employed for painting all forts of figures or land-
{capes in arabefgue, in the manner of diftemper or de gauche,
When they are perfectly dry, they are then covered with
white liquid wax, warmed by burning coals placed in a
chaffing-difh: when the wax begins to melt, it is fpread out
by means of a badger-hair brufh, to render it every where
equal ; and when cool, a polifh and luftre are given to it with
a proper rubber or piece of foft cloth.

The fecond method of preparation, which was rustle
more convenient, is the following: Having put an equal
quantity of white wax grated and of gum arabic in an earthen
veflel, with as much water as may be neceflary to render it
more or lefs thick, according to pleafure, the fame procefs
is then to be followed as in the preceding cafe: the colours
muft be finely ground with this mixture, and may then be
employed for painting.

Thefe two preparations were employed with great fuccefs,
for three years, to paint various pictures, decorations and
ornaments, ordered by the emprefs of Ruffia; and the
tranfparency of the colours produced a moft brilliant effect.
In the beginning of the year 1791 the three ableft artifts i in
encauflo, M. dell’ Era, in the hiftorical line; M. Cam-
povecchio for landfeapes; and M. Vincent Angeloni for
arabefque ornaments, ufed them with a very happy effeét,
and the pieces they produced were not inférior in luftre and
brilliancy to the fineft paintings in oil mixed with varnith.
Several trials were made in this way on walls, wood, cloth,
paper, copper, and marble; and it was found that paintings
9n the latter fubfances could be wafhed by means of a fponge
; : Dd4 . dipped

:

408 Methods employed in Encauftic Painting.
dipped in water, but that too ftrong fri@ion i sapabofs ta
the colours, and carried off a part of them. Paintings on
walls or wooden pannels refifted friction much better; but
if the hand preffed too hard, fome of the colour was hg
firoyed, efpecially i places to which the liquid wax had not
fufficiently penetrated,
(To ‘prevent thele inconveniences, trial was made of other
‘preparations, pointed out before by the Abbe’ Requeno,
avredably to feveral paffages of Pliny and Vitruvius. Thefe
trials were perfectly fuccetsful, and paintings executed with
the preparations, as hereafter mentioned, refifted much bet-
ter friGtion with a wet fponge. The mechanifm even of
painting in this manner, with thefe colours, was found
More convenient and much eafier, becaufe the colours did
not dry fo fpeedily as thofe prepared | in the firft and fecond
manner.

. The preparation of lenis agreeably to the laft method is
as follows: Take a vafe of vitrified earth, and place it over

& fmall fire with an ounge of white wax ; and when the wax is

"melted, add four ounces of olibanum (incen/9 ma/chio,) reduced
to powder, which muft be alfo diffolved with the wax. This
mixture muft be put into a fmall vetlel with water, and you
will obtain a hard brittle crayon, which muft be mixed
with the colours when ground up.

Tlie fame procefs may be followed with maftic, by taking
five ounces of that fubftance and two of wax, and this crayon
will ferve for the brighter colours. For darker colours the
srayon may be made of four ounces of afphaljos and twa
ounces of wax.

Method of making Di/lemper for preparing the Colours.

Infufe, for twenty-four hours, a pound of the gum of the
eherry-tree, and, when it is diflolved, put it into a fmall
earthen veifel, and boil it with two ounces of wax and half
anunce of olibanum reduced to a fine powder. When
this liquor is cool, take of the wax which feats on the top,

y . and

Fd

Chemical Obfervations on the Epidermis. “409
and then mix the liquid with the colours, in order to ren-
derthem more oily and fluid. Care muft be taken that this
preparation be alittle thick.

KIV. Chemical Obfervations on the Epidermis. By J. A,
. Caapraz. From Annales de Chimie, Vol. XXVI.

aks HE epidermis of the human {kin is perhaps the beft
expanded and the eafieft to be detached of any, and for that
reafon I made it the fubject of the following experiments. :

The human {kin becomes {hrivelled in hot water, and

divides itfelf into two diftin€t parts, the epzdermis and the

cutis. The latter refembles then in its confiftence a foftened
cartilage. The continued action of warm water at length
diffolves the cutis, but does not fenfibly affect the epidermis.
Alcohol kept a long time in digeftion on the epidermis
likewife produces no effect. Cauttic alkali diffolves it, and
the fame effect is produced by lime, though more flowly,
There is then an analogy between the external covering of
the human body and that which covers filk. From thefe
obfervations we are authorifed to deduce the following con-

fequences, which may be applied, without overftraining the

pe produced,

principle, to the operations of tanning. 1. If we plunge
into a tanning infufion a piece of fkin covered by its epi-
dermis, the tan penetrates only on the flefh-fide: the other
fide is fecured from it by the epidermis, which is not fufeep-
tible of any combination with the tanning principle,

2. When the epidermis is removed by the operation of
liming, the tan then fenetrates on both fides of the fkin.

3- Lime, which is generally employed for taking off the’
hair, feems to act only by diffolving the epidermis. Lime-
water has more action than undiffolved lime; but its efle&
eeafes the moment that the fmall quantity of lime held in
folution is combined with the epidermis : hence the necef-
_ fity of renewing the lime-water till the whole effect sere

XV, Of

[ 410° J

XV. Of a remarkable Cure effected by the Ufe of Carbonit

Acid Gas, communicated in a Letter to bis Excellency
Prince Demetrius de Golitzin, Minifter of the Imperial
Court of Ruffia at the Hague. By M. D. JANSENS of
Ooflerbout. From the New Tranfactions of the Imperial
Academy of Sciences at Peterfburgh, Vol. I.

Ooiterhout, Nov. 23d, 1778.

In the converfation I had the honour of having with your
Excellency on the medical virtue of carbonic acid gas, or fixed
air, I promifed to give you an account of the effeéts it might
‘produce in the putrid fever, by being injeéted into the rec-
tum; but though in the following cafe, which is certainly
very uncommon, [| have not exactly followed the method
pointed out by your Excellency, haying been ebliged to give
as much of the cinchona or Peruvian bark as pofftble, I
however believe that it ¢reatly contributed to the cure.

The wife of a bargeman at G. Berg, named N. Swart,

aged thirty-two, of a fanguine temperament and a found -

conftitution from the time of her birth, was attacked, after
her third natural delivery, according to every appearance a
favourable one, which happened on the 6th of Oétober at
two o’clock in the morning, with a fever that beaan on the
8th. It may be right to premife, that on the 6th the was

exceedingly well, and her evacuations were perfectly free.

On the 7th they flowed lefs, and fhe began to complain
of laffitude, .a great heavinefs in all her limbs attended with
a lofs of appetite, and the difappearance of milk ‘from her
breafts. At the commencement of the third day. the eva-
cuations were ftopped, and the fever came on by cold and
fucceflive fits of fhivering with reaching and pain in the
head, which was not acute, but accompanied with a fenfa-

tion like that of a weight preffing on the cranium, and frona ~

which fhe fuffered lefs when in bed than when fitting up.
Thefe fymptoms were followed by a creat heat, with vomits

ing of a bilious, ereenifh, highly corrupted ftuff: ber tongue ©

wet

af

A Cure by Carbonic Acid Gas. 411

wes covered with a vifcous matter of a yellowifh colour the
two firft days, but it was afterwards brown till the 6th.

Her breathing was fhort, oppreflive, and accompanied
with a fetid fmell. The pulfe, which was weak, beat from
go to 94 in a minute. The heat was not examined by
a thermometer. The urine was red and fetid, without
fediment. The patient had a violent thirft, and drank a
great deal of whey with lemon juice.

On the fecond day of the fever fhe was affected with
delirium, coma, reftleffnefs, and a dread of death. On
the third all thefe fymptoms increafed. On the fourth
there was an involuntary difcharge of urine, &c. On
the fifth there came on a diarrheea of a bilious and pu-
trid matter; and the delirium being then continual, fhe fuf-
fered every thing to efcape her. On the fixth the fymptoms

’ were no better. On the feventh the tonfils were white, and

this thickened fecretion, at length, covered all the parts of

‘the mouth; deglutition became difficult, there was fubfultus

tendinum, and the patient with her trembling fingers picked
the blankets. On the eighth all the fymptoms were as be-
fore, with vibices half an inch in diameter, which rofe in
{mall blifters, and appeared on, the breaft, the hands, and
other parts of the body. On the ninth thefe blifters dif-
charged blood, for the moft part thin and corrupted, the
ground of which was in fome a brown purple, and in others

red. The cheeks were alfo of a brown purple colour, the

eyes hollow, and the pupils much dilated. At laft a cold

fweat broke out on the face, the hands and feet; the mouth

.
a oe?
‘

_ quivered, and the cheeks, lips, and all the members of the

body were flightly convulfed.

All thefe bad fymptoms gave reafon to be apprehenfive
for the life of the patient; but the pulfe continuing regu-
lar gave me fome hope. .While the patient was in this
condition, being called in to confult with the phyfician who
had treated the ‘cafe according to the rules of the art, I ad-
yifed the application of carbonic acid gas by the re&tum, to-

bis) | : gether

412 A Cure by Carbonic Acid Gas.

gether with the following decoction: Twenty-five grains of
falt of tartar (carbonat of potafh) diffolved in five ounces
of a ftrong deco&ion of bark. I gave five ounces of this
decoction, in which I had put as many drops of fpirit of
yitriol (fulphuric acid), to extricate the fixed air.

This injeCtion was given twice the two firft days, and
only once daily for the three following. |

In regard to medicine, the patient took every hour, in a
cup-full of tea, the following decoétion : Cinchona or bark
m a coarfe powder, four ounces, digefted in a fufficient
quantity of common water for three hours, till reduced to
two pounds. I diffolved ina pound of this decottion a grain
of falt of tartar, to which I added the other pound, into which
1 had putas many drops of fpirit of vitriol as were neceflary
to faturate the alkali, and difengage the carbonic acid gas*.

On the tenth day all the fymptoms were the fame, ex-
cept that the fweats were lefs cold. On the eleventh they
were ftill Tefs fo; and perfpiration proceeding equally from
every part of the body, the tonfils began to look better,
deglutition was not fo difficult, and the delitriam was not
fo continual. From time to time the patient was collected,
and called for the urinal.

The twelfth and thirteenth fhe was ftill much better; the
colour of the cheeks was almoft natural, and the vibices
became of a brighter red; the convulfions ceafed, and all
- the other fymptoms had almot difappeared. On the four-
teenth a perfect crifis took place in regard to the urine and .
perfpiration. On the fifteenth the patient felt no more
fever, and had no fymptom of difeafe except great debility; _
fo that on the twentieth day fhe was perfectly re-eftablithed.

During the courle of the difeafe her breafts were flaccid
and very {mall, without milk; but having vifited her on the

* This does not appear to be the beft metlied that might have been
devifed for introducing the carbonic acid gas. In faét, the greateft part
of that cxtricated from the carbonat would be thrown off at the moment
‘¢ joining the ingredients. Rpir,

R

+
Ne

a

ee as

eS Pe

et >

a

On the Foffil Bonds oft Ouadrubedss 47%
tenth of November, I faw milk iffue from her breaft; and, -
as fhe had almoft recovered her ftrength, I advifed her to
Tet her infant try to fuck, and the milk was reftored.

i have been particular in detailing this cafe, that your
Excellency, from the circumftances both of the nature of
the difeafe and of its caufe, which was probably a floppage
of the floodings after delivery, might the better be enabled
to judge of the medical virtue of carbonic acid gas; and,
at the fame time, to fee the reafons I have had for varying
the application. I was afraid of a putrefaétion or’ univerfal
gangrene; againft which I preferibed bark ; and as the
latter could not prevent the extrication of the carbonic acid
gas, I added the fubftances neceffary to produce it.

AVI. Extraé of a Memoir on the Foffid Bones of Qua-
drupeds. By Cit. Curren. From Bulletin des Sciences,
No. XVIII. :

a HE author’s 3 object in this memeir was to collie, as

far as poflible, every mformation refpecting the various
kinds of foffi] bones hitherto found, whether feen by him-
felf or defcribed by others; to examine the fkeictons, and
to compare them w ith thofe of animals now exifting on the
globe, i in order to determine how far they are fimilar or
different. The following are the kinds which he examined :
1. The bones and tufks called by the Ruffians the bones
and horns of the mammoth. Such foflil remains are

found in various parts of Europe, This animal is a kind
“of elephant nearly refembling that of Afia, but differs from

it in the alveoli of its tufks being longer ; that the angle
formed by its lower jaw is more obtufe, and that the la-
mine of which its grinders are compofed are thinner. A
hhving animal really analogous to it is not known, though it

has hitherto been confidered as a common elephant.
a. The

‘ 1

4th On the Foffil Bones of Quadrupeds.

2. The remains of an animal which have been found é#
the banks of the Ohio in North America, and which the
Americans and the Englifh confider as thofe of the mam-~
moth alfo, though this animal is very different from the
preceding. Remains of it are found alfo in Europe and Afia
It muft be almoft of the fame height as the elephant,
but more bulky. Its tufks are fmatler ; its grindets are
armed with large cutting points, the fection of which pre-
fents, when they are worn down, double tranfverfal lo-
zenges. There are three grinders on each fide; one of
which has four points, the fecond fix, and the other eight.

Le The animal, the teeth of which tinged by copper
furnifh the turquois. Of thefe foffils there was a mine at
Sinore in Languedoc. Remains -of the fame kind are
found in the department of Ain, in Peru, and other places.
This animal muft haye refembled the preceding; but the
points of its grinders are of a conical form, and, when
worn down, their fection prefents, firft a circle, then a
femi-oval, and then the figure of a trefoil; which has made
them be confounded with the teeth of the hippopotamus.
Some of thefe teeth have twelve points, others fix, and
others four, ,

4. The hippopotamus. There are found in France, and
other countries, teeth and the fragments of jaw bones, in
which the author has never yet been able to difcover any
thing different from thofe of the common hippopotami. As
he never faw, however, a whole bone, he cannot affirm the
identity.

5.. That {pecies of rhinoceros with an elongated cranium,
the bones of which are found in Siberia, Germany, and
other countries. The author has feen teeth and portions:
of the jaws found in France, which appeared to him to be-
long to this animal. The principal characterifing mark of
this fpecies confifts in the ofleous partition of the nofe. A,
living animal analogous to it is unknown.

6. A

On the Poffil Bones of Quadrupeds. 41%

§. A grinder with two tranfverfal eminences, in the pof+
feifion of Cit. Gillet, and of which a germ is preferved in
the National Mufeum. It has no refemblance to the teeth,
nor to the germs of the teeth, of any animal, whether living
or in a foffil ftate; hitherto known. The only teeth to
which it bears a refemblance is the laft lower grinder of
the rhinoceres. This tooth indicates, then, the exiftence
ef a fixth foffil fpecies analogous to no living animal
_known.

7. The animal, twelve feet in Jength and fix in height,
the tkeleton of which was found below the earth in Para-
guay, and is now preferved in the Cabinet of Natural Hif-
tory belonging to the king of Spain at Madrid. By a mi-
nute comparifon of the bones of this fkeleton with thofe of
all the known quadrupeds, the author proves that it is a pe-
culiar and diftinét {pecies, which appreaches nearer to the
floth than to any other kind, and that it might be named
the giant-floth. Cit. Cuvier here mentions, occafionally,
an interefting difcovery he has made, that the ai, or three-
toed floth (dradypus trida&ylus, Lin.) has naturally and
anyariably nine cervical vertebra. This is the firft known
exception to the rule eftablifhed by C. Daubenton, that all
the viviparous quadrupeds have neither more nor lefs than
feyen cervical. vertebrae. |

8. The animal, remains of which are found in the ca-
verns near Gaylenreuth and Muggendorf, in the margraviate
of Bayreuth in Franconia., Several have confidered this
animal as a fea-bear; but it differs from it, as well as from
all the bears known, in the form of its head, characterifed
above all by the projection of the forehead; the want of
the {mall tooth, which the bears hitherto known have. be-
hind each canine tooth ; by the offeous canal of the hume-

Tus, through which the tracheal artery pafles; and by
feveral other circumftances in the figure and proportion of
the bones. It is however to the bear that this animal has
the greateft affinity.

g. The carnivorous animal, bones of which are foynd in

6 the

?

416 oe” Cgsale Foffil Bones: of Quadrupeds.

bones, the number of its grinders, the points with which
they are armed, indicate that this fpecies mutt belong to the
genus of the canis. It however does not exaétly, refemble any
known {pecies of that genus. The moft ftriking diftinétive
mark is, that the feventh lower grinder is the greateft in
the animal of Montmartre ; whereas it is the fifth im the
dog, wolf, fox, &c.

10. The animal, a lower jaw of which, found near Ve-
tona, has been confidered by Jofeph Monti as a portion of
the cranium of the fea-cow; -an opinion adopted by all
geologifts, though contrary to the fimpleft principles of com-
parative anatomy. This jaw, according to Cit. Cuvier, has
belonged to an animal approaching near to the mammoth,
the animal of the Ohio, and that of Sinore, though fpeci-

fically different. Its moft particular chara¢terifing mark -

confifts in the beak formed by its fympby‘is.
1r. The animal of the ftag kind, bones and-horns of

which are found in Ireland, England, at Maefiricht, Sea

It is evidently diftinct from all the ftags known, and even

~~ from the elk, to which it has been referred, on account of

the enormous fize of its horns, the flatnefs of the upper
part of them, and the branches that arife from the root.
Several’ figures of them may be feen in the Philofophicat
Tranfactions. |

. The genus of the ox alone furnithes feveral fpecies of
foffils. The fkulls of tivo which have been defcribed by
Pallas, were found in Siberia. One of thefe he referred to
the common buffalo; but he afterwards referred it to a par-
ticular fpecies named arni, originating from Thibet. Cit.
Cuvier proves, by ofteological comparifon, that this fkulb
doesnot belong to the buffalo. The other kind appeared to
Pallas to belong to the buffalo of the Cape, or the mufk-
ox of Canada. Cit. Cuyier fhews that they could not have
belonged to the former; but, not having the cranium of
the arni nor the mufk-ox, he does not {peak with certainty
“ their identity or.non-identity with thefe foffil crania.
Aira! The

" the plafter ftone of ‘Montmartre. The form of its ee :

On Atmofpheric Airs. 417

‘The author defctibes, alfo, two fortsiof crania found in the

moffes in the department of La Somme;.and which have d
great refemblance to thofe! of the urus, which are nearly oné
fourth larger.) 1’ ;
« Cit» Cuvier concludes his: refearches as follows 201. Ite
not agreeable to truth; to aflert that the animals of the fouth
have! formerly»exifted in:the north, their fpecies not being
perfectly identic. 2. That there have exifted in all couns
tries ‘animals! which do not exit at prefent, and that laretno
where!to.be fount) many known: part of the globe.:He
therefore” leaves it to geologifts to. make fuch changes or ad
ditions, ‘inipegard to their fy{téms, as: they may think necef+

fary to explain the facts which he’ has thus) eftablithed,

vw

XVII. Odbjfervations on the Conftituent ‘Paris of Atmofpberic
. Air. By Count de Morozzo. With, the Remarks of

F.. Van Humepotr. > From ibe Journal de Phyfique,
. Fruétidor, 6ib Year.

Ix the memoir which I;publifhed in 1784, on animal
refpiration in dephlogifticated or oxygen gas, I offered fome
reflections refpecting the conftituent parts of atmofpheric

. air, founded ion experiments [ had made. Layoifier, in his

Elementary Treatife'of Chemiftry, does not agree with my
experiments. That author fays, that the component parts
of atmofpheric air are 73 parts of mephitic or azotic gas, and
27 of oxygen gas, eminently ;refpirable. It-will then be
feen, adds he; that when animal fubftances are diffolved in
the nitric acid, there is difengaged.a great quantity of gas,
which. extinguifhes a lighted candle, injures animals, and

which has a perfect refemblance to that part of atmofpheric

air which is:unfit for. refpiration. If to 73) parts of this fluid
we add 27 of oxygen gas, obtained from,mereury reduced

tothe ftate of an oxyde by calcination, there is formed a

Vou. I. Ee fluid

418 On the Conflituent Parts

fluid perfectly fimilar to that of the atmofphere, and whic
has all its properties,

The. following, on the other hand, are the corollaries
which I have deduced from a great number of experiments
made to afcertain the duration of animal life in noxious
-aeriform fluids, mixed in different proportions with oxygen
gas, tending to illuftrate the real is ane of atmofpheric
air.

1. The examination by means of burning tapers is not
accurate for afcertaining the falubrity of the air. I fhall
quote only two examples, A fifth part of oxygen gas
mixed with air contaminated by the vapour of fulphur,
fuffered a candle to burn, while an animal fhut up in it
died in a few feconds. A feventh part of the fame gas
mixed with air vitiated by the vapour of charcoal, fupported
flame, while an animal died in it almoft inftantaneoufly.

2. That pure and falutary part faid to be contained in at-
mofpheric air, which forms a third of it according to
Scheele, and a fourth according to Lavoifier, is not a real
dephlogifticated oxygen gas; fince this gas united with
mephitic airs, in a much lefs proportion than a third or
fourth, fupports the flame of a candle after an animal dies
in it, which is not the cafe with atmofpheric air.

3. The real component parts of atmofpheric air are ftill
unknown; fince, with a mixture of different gafes, no-
thing has been obtained but compound gafes, which have
indeed fome properties of air, but never thofe of atmo-
fpheric air.

The author, to illuftrate the queftion, relates eight cha-
racterifing marks of atmofpheric air, acknowledged by phi-.
lofophers; and adds, that though he tried, by a multitude
of experiments, to compofe atmofpheric air, by mixing de-
phlogifticated gas with different mephitic gafes, the gafes
fo obtained always contained fomething not to be found
in atmofpheric air,

He

of Atmopheric Air. 419
He repeated the experiments of Lavoifier, by mixing 73
parts of fixed air (carbonic acid gas), obtained from lime,

with 27 of gas obtained from the red precipitate. This

mixture, indeed, exhibited to him all the charaéters and
properties of atmofpheric air, but it differed confiderably
from it in its effential property.

A candle is fuddenly extinguifhed in atmofpheric air in
which an animal has died; another animal could not live in
it an inftant. On the other hand, in this artificial mixture,
a flame burnt with vivacity; and a fecond animal, a fpar-
row, lived 25 minutes, a third 14 or 15: a light, introduced
after the death of the third fparrow, burnt ftill with a bright
flame. “ This mixture then does not form an elaftic fluid
perfectly fimilar to that of atmofpberic air, and having all
its properties.’ He tried to add to this mixture phlogifti-
cated gas, inflammable air, and that in which an animal
had died. A fecond and third animal lived in them fome
time, and a candle was not extinguithed.

Remarks on the above Obfervations, by F. Von Humbolt.

The memoir of Count Morozzo treats of a very important
fubje&t, with which I have been engaged for fome months.
The Italian philofopher has obferved the difference between

‘natural atmofpheric air and an artificial compound of azot

and oxigen; but, in my opinion, he goes too far, in affert-
ing that atmofpheric oxygen is not vital gas; though I agree
with him that we are not able to form an aeriform fluid,
fuch as the illuftrious Lavoifier announces in his Elements
of Chemiftry, perfectly fimilar to that of the atmofphere.
I however find that this difficulty confifts neither in our
ignorance of the quantity, nor of the quality of the two
gafeous bafes. The difference found between the effect of
naturM and artificial atmofpheric air, is to be afcribed to the
Slate of the combination in which the oxygen is joined to the
azot. The atmofphere-is not a mzxture: its comitituent
parts ought to be confidered as in a ftate of chemical combi-
Ee2 nation.

yd, A

hg

eae ty |

i On the Conflituent Parts, Se.

nation. tis for this reafon that the two bafes of a fpecifie
gravity fo different, that of azot and that of oxygen, do not
entirely feparate from each other, though the high regi

are moft charged with azot. ' Hence azot retains fo ftron

the laft portion of the oxygen, which phofphorus, the ful-
phure of potafh, and other acidifiable bafes ought to take
from it; and I have for this reafon feen that the nitrous gas
acts in proportions very different in decompofing the natural
atmofpheric air, or a compound of 27 of oxygen and 73 of.
azot. But how could Morozzo think to imitate the atmo-
{phere by mixing the carbonic acid and oxygen? He has
confounded azot with the carbonic acid gas. But he affures
us that his atmofpherit air with a carbonic acid bafe, gave
the fame fpecific weight as atmofpheric air. Here is a
very ftriking experiment: one cubic inch of azot weighing
0,46624 erdins, while the fame cubic inch of carboni¢
acid weighed 0,67500 grains! Morozzo tells us that a
candle burnt in his artificial mixture with a very brilliant
flame (con fiamma lucidiffima). By combining 0,25 of the
carbonic acid with 0,75 of oxygen, I have feen a wax taper
extinguifhed. The fame thing took place when in com-
pany with Taffeart in Vauquelin’s laboratory, I mixed two
parts of the carbonic acid gas with ten parts of atmofpherie
air. There is then formed a new chemical combination :

the carbonic acid lays hold fo ftrongly of the oxygen of the

atmofphere, that the affinity prefented by the lighted wax
taper is not powerful enough to take it away. In my
work on the analyfis of the mephitic vapour of mines,
which is about to be tranflated into French, it will be feen
that there exifts airs not unfit for refpiration, which aré com-

pofed of 0,27 of oxygen, 0,70 of azot, and 0,03 of carbonic
acid gas. It is the fate of the combination, and not always the

quantity of oxygen, which renders air more or lefs capable te
deftroy animal life, or to extinguifh flame.

XVIII. Cur-

[ 42x

XVII. Curfory View of fome of the late Difcoveries in Science.

[Continued from the laft Number, page 209.]
LUMINOUS FLUID.

‘Tuer are two principal opinions entertained by phi-
lofophers refpecting the nature’of the himinous fluid. Some,
with the fchool of Epicurus, think that this fluid is a conti-
nual emanation of the luminous body which throws toa
diftance a portion of its fubftance. This is what is called
the emiffion of light, and was the opinion adopted by
Newton. .

Others, among whom is Euler, think that the luminous
fluid is diffufed throughout infinite fpace, and that it is aéted
upon by the luminous bodies as the air is by fonorous bo-
dies. This opinion appears to Cit. de la Metherie much
more probable than the former.

One of the ftrongeft objections made to this opinion is, that
light is never propagated but ina ftraight line, ObjeGts cannot
beffeen, except when no opake body is interpofed between

‘them and the eye, whereas founds are heard in every kind
gf direction. Euler replied to this, by faying, that bodies are
permeable to founds. . Befides there are circumftances where
founds alfo cannot be propagated but in a right line; for
‘example, in echoes which are heard only in a very {mall
{pace. “tes

Chemifts likewife are divided in their opinions refpecting
the luminous. fluid. Some believe it to be an elementary
fubftance, and others have confounded it with fire. Richter
believes that it is compofed of the inflammable principle and
caloric. 4

Benediét Preyoft has endeavoured to eftimate the gravity
of the luminous fluid. He made to float on water very thin
round plates of tin; and thefe bodies were repelled when a
eylinder of red hot iron was prefented to them obliquely at
fome diftance, or when the rays of the fun collected into a

; Ee3 focus

422 Curfory View of fome of the late Difcoveries in Science.

focus by a lens were made to fall upon them. Prevott is of
opinion that the rays of the fun penetrating the tin-plate are
thus combined with a matter more denfe, and form therein
a very expanfible fluid; but being lefs fubtle, it becomes fuf-
ceptible of aéting by impulfion on very large maffes, and
ifuing with impetuofity from the plate, but more rapidly
from the focus, pufhes it backwards, and purfues its way
through the water, which aéts as a conduétor to this fluid.
The author conjectures, from thefe experiments, that it is
poffible to deterrmine the gravity of light. It is well known
that it takes about eight feconds te come from the fun to the
earth, that is to fay, to traverfe a {pace of about thirty-three
millions of leagues. According to fome fuppofitions, he finds
that the light which in a fecond of time falls upon the fur-
face of a fquare league, containing 2,283 toifes on each fide,
would weigh about a dram (gros) and a quarter. It may be
readily perceived that all thefe calculations are very hypothe-
‘tical; and we may add, that from fome experiments made
by Profeffor Wilfon of Glafgow*, with a view to a different
objeét, there is reafon for calling in queftion the effeé pro-
duced upon the thin plates, or tin foil, as being at all pro-
duced by the impulfe of light. Heat only feems to be here
concerned, The water at firft being of an uniform tempera- —
ture, has all its parts in a ftate of equilibrium and reft.
When the tin foil is heated, it is evident that a very active
eaufe is introduced tending to deftroy that equilibrium. Heat
being communicated by the tin to the water in conta@ with
it, that portion of the water endeavouring by its expanfion to
move from under the tin, muft tend to move the tin from its
place,
[To be continued. ]

* See the Profeffor’s experiments on fmall lighted wicks floating onoil,

ipferted in the Edinburgh Tranfaétions, Vol. IV. See alfo Count Rum-
ford’s Experiments on Heat,

XIX. Come

[ 423 ]

XIX. Communication from Dr. THORNTON, Leéurer on
Medical Botany at Guy’s Hofpital, refpeéting a fuppofea
Lufus Natura now exhibiting in London.

N the firft volume of the Philofophical Tranfactions,
No. XXIX. publifhed November 1667, you have the fol-
lowing communication, entitled,

“© Some Hortulan Experiments about the engrafting of
Oranges and Lemons or Citrons, whereby is produced an
individual Fruit, half Orange and half Lemon, growing
together as one Body upon the fame Tree.”

We have here orange trees (faith the intelligence from
Florence), that bear a fruit which is citron on one fide and
orange on the other. They have been brought hither out
of other countries, and they are now much propagated by -
engrafting. This was confirmed to us (fays the Editor of
the Tranfactions of the Royal Society), by a very ingenious
Englifh gentleman, who afferted, that himfelf not only
had feen, but bought of them, anno 1660, in Paris,
whither they had been fent by Genoa merchants; and
that on fome trees he had found an orange on one branch,
and a lemon on another branch, (which is not fo remark-
able as what follows;) as alfo, one of the fame fruit,
half orange and half lemon; and fometimes three quarters
of one, and a quarter of the other.

In the third part of the Reports of the Board of Agri-
culture, among the foreign communications, we fee, with
equal pleafure and aftonifhment, an account of the Ameri-
can apple, which, by a peculiar mode of budding *, is
half fweet and half four, half white and half red, with-
out the leaft confufion of the refpective halves.

At Mr. Mafon’s, florift, Fleet-ftreet, oppofite the Bolt
and Tun, there is a production now to be feen half peach and
half neétarine. It has all the foftnefs and yellow down of

* The manner in which the extraordinary nectarine-peach firft pro-
duecd in this country was effeéted, was by inferting the bud of one fruit
upon the flock bearing a different fort.

Ee4 the

see | 3 ‘ ®
424 Prize Queflion. |
the peach, and the fleck, red fmoothnefs of the neétarines
fuppofed to be a lufus nature, but probably i is rather the
{portings of art, than of nature, and which perhaps will be
the caufe why we fhall in future fee many other fuch vege-~
table wonders, which, .as, I have fhewn,.were known'to our —
ancettors. tiv
Refpedting my ‘promifed communication concerning the
filk.worm,, I.muft beg leave to delay it, until I have afcer-
tained for certain the difference of the Chinefe, from the .
mulberry trees, cultivated here ; the former being, Ihave rea-
fon to believe, only.a fhrub, with, a very broad leaf, and
dying down to the ground eyery year, {pringing up the next.

TNE EE Ft CPE er ee
LEARNED SOCIETY. |

Put directors of the Imperial Academy of the Searchers
into Nature, have propofed the following queftions as fub-
it for prizes.

I. In which of the known parts of vegetable produétions,
the bark (corfew), inner bark (/iber), w ood (alburnum. et
lignum), pith (medulla), does the fap afcend? Does a reflux,
of the fap towards the root, proportioned to the afcent, take
place in the bark or the pith, or in both? And, if this be
the cafe, by what way is it conveyed from the interior parts
to the bark? What courfe does it, in particular, take to pals
through the leaves to the bark ?

The Academy wifhes, in particular, that the motion of
the fap in the bark upwards may be proved or refuted ; both
by a careful repetition, varying the circumftances, of the ex-
periments which have already been adduced as a proof of it,
and by a fufficient number of weil chofen and appropriate
new experiments. The beft founded experiments, which
prove the afcent of {ap in plants, have been enumerated by
Duhamel, in Phy/figue des Arbres, b. v. chap. 2) art. 7—1T,

6 _and

: \ she

as

Prize Que/ftion. 425
and the moft important of them are as follows: 1. If a
plant «is fuffered to imbibe a coloured fluid, it afcends in the
vellels between the pith and «the bark, penetrates to the
leaves, and then proceeds through the bark a certain {pace
downwards. 2. When‘a plant or a twig is compreffed at
the bottom by a ligature; a fwelling takes place upwards
towards the ligature.. 3. When the bark of a tree is taken
off, without injuring the interior part, the upper edge of the
wound produces a greater quantity of moifture than the
under. 4. Under thefe circumftances an excrefcence is
formed on the upper part of the bark, and not on the
under; and the renovation of the inner ‘bark, which has
been ldft, takes place from the top downwards,

Ii. What beneficial ufe may practical medicine derive
from Humboldt’s well known experiments on Galvanifm and
metallic irritation ?

The Academy expects that. the difeafes and cafes, in
which Galvanifm may be ufeful, will be accurately deter-
mined by proper experiments; and that the experi
will be clearly and fully defcribed. Experiments,
on perfons apparently dead, are to be omitted, og gt

The Academy requefts all anfwers to_thefe quettiog®@ if
founded on experiments actually made aa the authors, to be
legibly written in-Latin; to be: inferibed sit any motto
according to pleafure; and to, be ‘accompa j6d with a fealed
note, haying on it the fame MOL» and containing in the
infide, the name, title and place of. refidence of the author ; 3
and to be tra pingitted, before the firft of Oétober 1799, to

Bi prefident, of. BAe G. H. R, von Schreber at

Erlangen. Seg pile des
The playa t each queftion, is a : gold medal “ae twenty

— ducats Value,. bearing the ufual impreflion, and_ will be ad-.

judged to the author of the beft papers, by the commiftionerg

~~ of the Academy, on the sth of January 1800.

ih |
MAGNETISM,

id

ot

426 Magnetifm, Mineralogy, &c.

MAGNETISM.

WEnzZEL has proved that cobalt is fufceptible of magnetic
attraction, and has magnetic poles. Klaproth has proved
that the pureft nickel, that even of the Chrifoprafus, is alfo
fufceptible of the fame attraction, and has magnetic poles.
The ferpentine of Humboldt has magnetic poles, but does
not attra iron. The cafe is the fame with feveral forts of
lava. Here then are bodies which have polarity, without
attraGting iron. Are there bodies which act upon irom
without having polarity? Tralles, a geometrician of Berne,
has taken very {mall fragments of Humboldt’s ferpentine,
which had very perceptible poles, and having placed them
clofe to very ftrong magnets, the poles of which were op-
pofite to thofe of the ferpentine, the poles of the ferpentine
became inverted,

MINERALOGY.

Several mineralogifis think that the metallic veins in
mines diminifh always in thicknefs the deeper they pro-
ceed; fo that thefe veins refemble a kind of wedge, the
bafe of which is directed towards the furface of the earth,
and the point towards the centre. But this is not precifely
the cafe. Several ¥éins appear indeed to be of that form;
but there are many others, the form of which is quite the
reverfe. Humboldt fays that the vein of Kuhchacht at
Freyberg, which contains argentiferous galena, grows
broader, inftead of becoming narrower, the deeper it goes ;
and yet it is one of the deepeft worked, as it proceeds to
the depth of feveral hundreds of fathoms. Thofe of
Golderonach in Franconia, which contain arfenical and
auriferous pyrites, are much broader at a certain depth than
at the furface.

COLD PRODUCED BY COMPRESSED AIR.

Thofe machines employed for ftrongly compreffing at-
mofpheric air are well known, Profeflor Pictet of Geneva
fays,

Phyfiology—Gravity of Water. "427
fays, he has feen this air, thus compreffed, produce a very
great degree of cold when the cocks were opened to fuffer
it to efeape. To demonftrate this in an eafy manner, let a
fmall quantity of water be put into a comprefling machine.
When the air efeapes, it iffues with a hiffing noife, and
carries with it a part of the water; and at the end of the
eperation, the water adhering to the cock, will be found
converted into ice. To explain this phenomenon, we may
fuppofe that a portion of the water, which is carried off by
the air, is reduced to an aeriform ftate, or that of vapour.
But this could not be the cafe, unlefs a pretty confiderable
quantity of caloric were combined with the vapour. The
remaining drops of water are therefore fufficiently deprived
of it to be congealed. It is in the fame manner that the
rapid evaporation of ether, applied to the ball of a thermo-
meter, makes the liquor fpeedily defcend feveral degrees.

PHYSIOLOGY.

Dr. Seoemmering has proved, by a great number of obfer-
vations, that the degree of intelligence of different animals
is always in proportion to the bulk of the brain, compared
with that of the nerves. Man has the moft voluminous
brain, and his nerves are very fmall: it is this which gives
him his high degree of intelligence. The afs has very large
nerves, and a very {mall brain. Dr. Ebel has publifhed on
this fubjeét a very interefting differtation, which we hope
foon to be able to lay before our readers,

GRAVITY OF WATER.

Bodies are dilated by warmth, and confequently become
fpecifically lighter the hotter they are. On the contrary,
they are contracted by cold, and become fo much denfer the
colder they are. But this law of condenfation is fubject to
fome exceptions: melted metal, for example, dilates to a
certain degree as it becomes folid; water experiences the

fame

» Wh Oe 7 4, ° =e ‘
\) og AL : «eae J
. .

428. . Mares

fame dilatation in’ ete To find then the ereateft .
fpecific gravity of water, we ought not to take ice, for we.
know that it fwims on water. We muft make choice of Pa
certam degree of heat between that of congelation and that
of expanfion. Experience has determined this point , to be

; about 41° of Fabrenheit. Confequenily, to find the greateft
quantity of water which can be contained in a veflel of a.
given capacity, we muii.take water at that temperature.

‘ This circumftance fhould be attended to in determining
meafures of capacity. .Some people are fo well aware of it
that they buy liquids in cold, and endeavour to fell them 1 ed
hot weather.

METEOROLOGY. 5

* On the roth inft, about twelve o’cleck at night, a re-
markable meteor was obferved by one of the mafters of the
-Free-fchool at Alnw ick, and another perfon; it appeared q
in the fouth-weft, at a confiderable altitude. At firftit was .
no bigger but far brighter than a common ftar, but prefently -
expanded into the ‘form -and fize of an apothecary’s pefile.
It was then obfcured by a cloud, which was {till illeminated
behind; when the cloud was difpelled, it re-appeared with
a direGion fouth and north, yith a fmall long ftreamer,
cutting the pefile a little below the centre, and iffuing away

to the eaftward. It was again obfeured, “and on its re-ap-

‘ pearance, the fireamer and peftle had formed the figure of a
hammer} or a crofs; prefently after the ftreamer, which’ »
made the fhaft to the hammer, or ftatk to the crofs, aflumed’
two horns, at the extreme point towards the eaft, refembling * K
a fork, It was then obfcured a third time, but when-the
cloud paffed over, it was changed into the fhape of two ha]f-- _

moons, back to back, having a fhort, thick luminous fiream
betw een the, two backs; it then vanifhed totally from their
fight, It is obfervable, that every new appearance became
_ brighter and brighter, till it became an exceedingly bril-
liant object, all the other-ftars in comparifon appearing to 4g

‘

Meizorology. 426
the ‘only dim fpecks, The time of obfetvation’ was above at
minutes. hilt Seb eitoak,

| The Decade Philofophique'contains an’ account of a biteu-
4ar phenomenon which was obferved on'the roth of Auguft
laft, at Caumont, principal town of the diftriét, at the ex.
‘tremity of the department of Calvados.—“ The weather
_ -was fine; a few light clouds fcattéred here and there in the
4 fky. The atmoiphere was loaded with vapours, the wind
: North Weft, the barometer at 28 and’a fraction, and Reau-
_ ‘miur’s thermonieter’ at between 18 and 19 degrees, abotit
: 72° of Faht. A’ circle of white clouds was formed about the
i altitude of the fun, paffed through its centre, ftretching uni-
U formly to the fame height in a horizontal planes | 'This’cir-
_ ‘ele, or belt, in its vreateft breadth, was nearly the fize' of
the fun’s femi-diameter. On this circle*were projected two

| parhelia or difks nearly of the fame fize as that of the fun,
from which they were at equal diftances; the one at the
right, the other at the left, at the diftance of. about 45 de-

. grees each from the fun. In each of thefe difks, the part op-
| pofite tothe fun wasvery luminous, to the extent of nearly three
parts of their diameter, and prefented-prifmatic colours. The
_ -reft was nebulous (that part ‘next the fun). “At ‘about 1ro
degrees from the fun on each fide, appeared two other difks |
traced upon the fame circle at equal diftances. But they
were perfectly of the fame whitenefs with the circle, and
were not quite round. A femicircle rofe above thé fun; and
formed an arch, the cord or bafe of which was a feétion of
‘the great white circle, the centre of which was the fun.
‘The radius of this femicircle was about 22 degrees, and ter-
‘minated on ‘each fide of the fan nearly at half the diftance
‘of the fun from each of the luminous difks. . This femi-
‘circle uniformly contained a yapour of a clear brown, the
“extremities of which, without any fhade, ran into the fur-
Tounding atmolphere.! This phenomenon continued - for
early a anhour. The citcle began to fade'‘on the’ North fide,
hel where

430 Dyeing.
where it neyer had been fo clearly marked out. The lnimf-
nous difk difappeared laft.

“ Thefe obfervations were made by a great reali of
people, as it was market day in the place. As prejudices
are ftill very ftrong in moft parts of the country, évery one
reafoned according to his religious or political prejudices—
Some faid that it was a fign of the anger of God againft the —
changes which had taken place: others, of an oppofite opi-
nion, faid that God had crowned the republic: others again
thought that the great circle which feemed to embrace all —
this hemifphere, announced a general peace.” The writer of »
the account concludes, ‘‘ I had no great difficulty in per- —
fuading the majority that thefe figns were the effect of the ¢
vapours and exhalations occafioned by the heat. Ten years
ago I fhould not have been fo fuccefsful.”

is

DYEING.

Cit. Chaptal, having been lately engaged inexamining the _
caufes of the fixity of certain yellow colours, has obferved, *
that the yellow colour extracted from vegetables is in general
in the inverfe ratio of its fplendour. He has endeavoured to
afcertain the caufe which renders the pale yellow more du-
rable, and has difcovered it in the exiftence of the tanning
principle, which is found united with the yellow principle *
in moft vegetables. By analyfing fuftic (morus tinétoria) he }

obtained, 1ft, a principle partaking of the nature of refins —
or gums, and which can communicate a beautiful yellow —
colour ;, 2d, an extractive principle, which is alfo yellow, —
and furnifhes a beautiful colour ; 3d, atanning principle, of
a pale yellow colour, which grows black in the air and by ©
ebullition—it tarnifhes the colour of the other two princi- —
ples. As it was neceffary to feparate the tanning principle,
in order to leave to the reft the full vivacity of their colour,
Chaptal found means to accomplith that obje& by a fimple
and cheap procefs, He boiled, with the wood, fome animal

fubftance

fe
* 2
U
Vy
*
i's
‘y

,

New Coinage. 431
fubftance containing gelatinous matter, fuch as bits of fkin,
ftrong glue, &c. The tanning principle precipitated itfelr
with the gelatinous matter, and the bath held in folution
only the principles which produce a lively and {trong yellow.
By the help of this procefs, colours as bright as thofe com-
municated by yellow weed (refeda Juteola) and quercitron
bark, may be procured from feveral vegetables.

NEW COINAGE.

We have already mentioned (p. 220.) that it was propofed
to improve our coin, and that the fubject was referred to the
Royal Academy. The following circular notice has been
fince iffued to the academicians.

** Royal Academy, Auguft 20th, 1798,
“ SIR,

“The Lords of the Committee of Council having exprefled
a defire that the gold and filver coins of this kingdom fhould
have every improvement which the prefent ftate of the arts
can afford, and the Royal Academy having agreed to take
the fame into their confideration, the prefident has accor-
dingly ordered a general meeting of the academicians on the
2oth of September next, at fevyen o’clock in the evening, to
receive the defigns or models of fuch of the members of the

_ academy as will then offer; which defigns or models are in-'

tended by the lords of the committee to be prefented for his

majefty’s infpection, previous to their being carried into
effect.

‘* The coins intended are as follow—
Gold—A two guinea piece, a guinea, and a half guinea.
Silver—Five fhilling piece, half crown ditto, one fhilling,
and fix-pence.
The head of his prefent majefty, the arms of the realm, the
lion, the crown, and Britannia.
“* In forming the defigns or models, it is defired that at-
tention be paid to the roundnefs and fimplicity of the coin ;
to

43% Saige 3
* t6. the whole ¢ or part of the infeription o on the fame, ae is.
guard againtt the ; Weating ¢ or fi ling.

Riper, a Ms « ‘¢ JOHN Ric ARDS, R. i Seoresatgi”

-In eoitfeliientd of 'the above notice, ‘a meeting took place
at the time appointed, when feveral drawings and models
were produced, ‘which were afterwards forwarded to the
Lords of the Committee of i for his mee) $s in«
fpection. be

» Much ought to be pe If hiftorical facts are not.to be -
recorded. on our coins, the whole intellect. and abilities. of!
the artifts 6f Great Britain ought to be concentrated as it.
-were in one focus to produce the acmé of excellence.

SURGERY.

_ We have to announce that a confiderable improvement
has lately been made on the German key for extraGting
teeth. Mr. Charles Brown, furgeon, having for fome time
paft turned his attention to the ftruéture and mechanical ~
powers of thofe inftruments ufed in the leffer operations of
furgery, it appeared to him, that the German-key moft
commonly in ufe, notwithftanding the various improyements
it has undergone, partly by profeffional men, and partly by
inftrument-makers, was not well calculated to extract teeth
with fafety and eafe. Having had great experience in this
particular branch of furgery, he endeav oured, and with fuc-
cefs, to remedy the defects that were {till obvious in the in-
ftrument. As the one produced by Mr. Brown pofeffes in
an eminent degree many advantages over all others, we fhall,
in a future’ number, prefent our readers with a defer iptios
of it, which the ingenious inventor has promifed to oe
us with, ilar ated with an engraving.’ In the miean time,
fach of our readers as with for a more early know ledze of its
ftructure, may fee one of them at Mr. W hitford’s, S, fur rgeon’s
inftrament-meker, in: the Cloifters, Sty Bartholomew the,
Lels, Smithfield. is Yi

AEagraved by Wlowry

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INDEX tro VOL. I.

Acrp, the zoonic, procured from animal fubftances, page 68.
wcid, the muriatic. Experiments tending to élucidate its origin,
2552 35?- :

_ Acid gas, a cure effeied by carbonic, 410,

Adrianople or Turkey Red, procefs for dyeing, 4, 126.
—— effets of mordants in the procefs, 274.
Africa, Mr. Parke’s journey into the interior of, 191, 235.
Agriculture, intelligence concerning, 110, 220, 320.
Air, cold produced by compreffed, 426.
| Mir, atmofpberic, remarks on, 437.
Alearrazas, Spanith method of manufacturing, 371.
Alcobol, on the expanfive force of the fteam of, 345.
American fugar maple, account of, 182, 322.
Analyfis of the earth of which alcarrazas are made, 373.
of the emerald of Pern, 204.
of the mineral {prings at Lemington Priors, 255, 35@.
Animal fibre, on the irritability of the, 307°
Animals, extract of a memoir on the fotfil bones of, 413.
Antiquities, intelligence concerning, 221.
Apparatus, defcription of Defvignes for impregnating water, 77.
— employed by Lavoifier to produce water, 303.
for transferring gas into bottles, bladders, &c. 303.
Arts, intelligence concerning the, 222.
Affaying, to purify lead for, 11.
Aftroncmy, difcoveries in, 59, 104.
Atmofpheric air, experiments on, 333.

ee

Bats, experiments on, 134, 136.
Bayen, Peter, biographical memoirs of, 212.

Beckmann, on foy, and the bean from which it is produced, 342.
Bentham, Samuel, Efg. account of his patent for facilitating manw-- -
facturing and economical procefies, 143.
Berthollet, on the zoonic acid, 68. - : *
Bettancourt’s experiments on the expanfive force of fteam, 345.
Biographical memoirs of P. Nieuwland, 69. ‘

— P. Bayen, 212.
Birds’ nefls, account of the eatable, 118.
Blue dye, procefs followed at Aftracan to give to cotton, 126.
Bones, extra&t of a memoir upon foffil, 413.
Vor. I, Ff Botany,

~

——_

434 INDEX

Botany, difcoveries in, page 62.

intelligence concerning, 109, 111, 336.

Botifas for cooling water, manufacture of, 374-

Braam, Vin, extraé&ts from his journal, 85.

Broken, account of the fpeétre of the, 232. °

Brugnatelii’s experiments to render paper indefiruétible by fire, 8g.

Bzurekhard, Dr. calculation of the orbit of the comet lately difco-
vered, 106.

Burja, Proféefor,on the folar and lunar period of 6co years, 32.

Butter, a kind of, produced from a tree in Africa, 238.

Canada, account of. the jumping moufe of; 285.

Cantaros for cooling water, manufa€ure of, 374.

‘Carbonic acid gas, a cure effected by, 410,

Cartwright, Mr. patent fteam engine invented by, 1.
Cavallo’s apparatus for trensferring gas, a defcription of, 395.
Chaptal on the effects produced by mordants in dyeing red, 274.
on the epidermis, and on tanning, 409.)

on the fixity of certain yellow culours, 430.

China, methodemployed to prepare foy in, 242.

Chrome, on the new metal {o called, 279, 361.

Cobalt, difcovery of a vein of, in Cornwall, irt.

Coin, propofal for improving, 220, 4,1.

Cold produced by compreffed air, 426.

Collier, Mr. Jofeph, his obfervations on iron and fteel, 46.
Comets, remarks, &c. on, 60, 104, 105, 106.

Conferva jugalis, a curious circumftance refpecting the, 307.
Copénbagen, prize queftions by the fociety of, 323.

Cryftals, theory of the ftruCture of, 35, 153, 287, 376.

Cuvier on the foffil bones of quadrupeds, 413.

Darcet’s analyfis of the earth of which alcarrazas, &c. are made,

373-

Davies's (Major-General) account of the jumping moufe of Ca-
nada, 285.

Defvignes's apparatus for impregrating water, defeription of, 77.

Difeafes, curable by metallic tractors, 251,

Dioptrics, experiments in, 22".

Dibbie, or the Dark Lake, fome account of, 239.

Difcoveries andimprovemens, view of fomelate ones, 59,208, 305, 42%

Dodd's propofal for a tunnel under the Thames from Gravefend ta
Tilbury, 223.

Dootys or head min in Africa, nature of their office, 241.

Dutch emba/fy.to China, fome particulars of the, 85.

Dyeing Turkey or Adrianople red, the procefs for, 4.

a‘ violet colour, procefs for, 56.

a new wood proper for, 92.

a blue, yellow, or green, procefs for, 126.

of the effects of mordants in, 274.

yellow colours, information concerning, 430.

Dynanometer, defcription and ufe of the, 399.

|

IN DEX. 438

Earthquakes, account of, page 106.

Earth worms, to deftroy or drive away, 169.

Economical proceffés, account of Mr. Bentham’s patent for, 148:

’ Elephants, {ome curious circumftances refpecting, 83.

Embaffy:of the Dutch to China, {ome particulars of the, 85.

Emerald of Peru, analyfis of, by Vauquelin, 204.

Enamel, black, to fill up engraved filver with, 405.

Encauftic painting, the proce(s : its antiquity and advantages, 23, 141.
————-, the procefs, according to Requeno, 406.

Englifb, Mr. John George, on river.and canal boats, 393.

Lpidermis, chemical obfervations on the, 409.

Equilibrium, principles of, applied to boats, 393.

Fabbroni, Ch, Sig. Giov. on encauftic painting, 23, 141.
, his account of the violet dye produced from the leaves of
fuccotrine aloes, 56.
Fernandez, D. report on a new wood proper for dyeing, 92.
Floating bodies, the principles of equilibrium, and the ftability of,
applied to river and canal boats, 393.
Force of men and animals, an inftrument to meafure the, 399.
Foffil bones, extra&t of a memoir upon, 413.
french National Inftitute, prizes propofed by the, 95, 326.
_—_—_ - proceedings of the, 100, 218, 328.
Frinch weights and meafures, explanation of, 245.
Furnace for converting iron into /leel, defcription of a, 55.

Galvanifm, experiments on, 319.
» prize queftion on, 425. ; ‘mba:
Gardening, intelligence concerning, 109.
Geoffroy,.De, on the orang outang, 337.
Germination, efie&ts of oxygen upon, 309.
Green dye, Aftracan procefs for a, 127.

Hamburgh, prize propofed by the fociety of, 102.
Hanhbemann’s teft for adulterated wine, 31.

Hawy’s theory of cryftallifation, 35, 46, 287, 376.
Herfzbel, Dr. opinions of, refpecting the fun, 59.
difcoveries by, 60, 104.

Hjelm, P. #. method for purifying lead for aflaying, rr.
Hochbeimer’s propofal for a new hygrometer, 367.
Hooke, Dr. defcription of his telegraph, 312.
Humbo!t on atmofpheric air,’ 419.

experiments on germination by, 309.
Hydroftatics, interefting experiments in, Or.
Hygrometer, propofal for a new, 367.

Imperial Academy, prize queftions by the, 424.

Ink, to prepare a fympathetic, 175.

Infeéts, to deftroy or drive away, 169.

Tron and fteel, obfervations on, 46.

drritability of the animal fibre, remarks. on, the, 307. w fi
bis os F f2 Facquin

436 INDEX.

Facquin on the production of founds by different gafcs, page 332.

Fapan, methods employed to prepare foy in, 342.

Jarras for cooling water, manufacture of, 374. .

Javanefe fwallow, defcription of the, 118. ; :

ale J. L. obfervations on the fpeGre of the broken, 232.
umping moufe of Canada, an account of the, 285.

Furine’s experiments on bats, 136,

Klaproth, Profeffor, on the new metal called tellurium, 78.

| Lalande, Cit. opinion refpeGiing the fun, 59, 205.
Lalande, jun. the number of ftars determined by, 106.
Lambe, Mr. William, analy fis of the mineral waters at Lemington
Priors, 255, 3.50.
Lafeyrie on the manufatture of alcarrazas, jarras, &e. 371.
Lavoifier’s apparatus to make water, a defcription of, 303.
Lead, to purify from gold or filver, to fit it for affaying, 11.
Learned fociettes, intelligence concegning, 95, 218, 323,424.
Lemington Priors, analyfis of the mineral waters at, 255, 35@
Lotus, bread made from the berries of the; 244.
Ludicke, M. on a cheap fubftitute for oi] paint, 22.
Luminous flnid, opinions concerning the, 421.
Lufus nature, remarks on a fuppoted, 423. - .

Magnetifm, influence of, om time-picces, 16.

—-—— cobalt, nickel, ferpentine, lava fuiceptible of, 426.

Maple fugar, procets for making, 182.

attempted to be made in 1634, 322.

Mathematics, difcovery in, 59.

Meafures and weights, intelligence concerning, 112.

= explanation of the French, 245.

Medicine, prize propofed by the Parifian fociety of, 99.

prize queftion by the Barcelona Royal Academy of, 325.

———— obfervations relating to, 64:

Mediterrancan, on a junction of the Red Sea with the, 12.

Meridian, method enyployed in France to meafure a portion of the,
269.

Metal, on the new one called teflurium, 78.

——-- a new ane called chrome, 274, 361.

Metallic traGors, their influence in curing difeafes, 250

Metcorolagy, obfervations on, 708. <

-- intelligence concerning, 428.

Meteors, an account of two, 606.

Mineralogy, intelligence concerning, 111, 334, 42%

Model of Paris, account of a, 222. ;

Molaff-s, to purity for ufe inttead of fugar, 398.

Money, divifions of the. French, 249.

Mosn, on the volcano of the, 69.

Moufe, account of the jumping one of Canada, 285.

Mordants, on their effects in dyeing cotton red, 274.

Muviatic acid, experiments tending to elucidate its origin, 255, 3 se

; LV aOR

INDEX. 437

Jational Inftitute, prizes propofed by the French, pages 95, 326.
ee proceedings of the French, 100, 218, 328.
Natural biftory, \ate difcoveries in, 209.
intelligence relating to, 336%

Nicholfon, Nr. P. on the mechanical power of the wedge, 316.
Mieuwland, P. biographical memoirs of, 69.
Niger, fome particulars refpefting the river, 202, 240.

Oil paint, a cheap fabftitute for, 22.

Oriental procefs for dyeing Turkey or Adrianople red, 4.

Orang outang, Wurmb’s defcription of the, 225.

- obfervations on Wurmb’s defcriptiom of the, 337.

- . Painting, the antiquity and advantages of encauftic, 23, 141.

-- the oldeft oil one in exiftence, a fhort account of, 30.

-- Requeno’s procefs for encauftic, 406.

Pallas, Profeffor, account of the procets employed at Aftracan for
dyeing Turkey red, 4.

~ on the irritability of fa fponges, 34.

Paper, experiments to render it indeftrutible by fire, 89, 173-

Paraguatan, ona new wood of that name proper for dyeing, 92.

Paris, account of 2 model of, 222.

Park's journey into the interior of Africa, 191, 235.

Parbeha, or mock funs, feen at Niort, &c. 67, 429.

Perkins’, Dr. difcovery of metallic tractors, 250.

Phenomenon, ov.a fingular one called the tpectre of the broken, 232.

Phyfiology, experiments, &c. in, 65, 427.

Plants, on the fenfibility of, 305.

Prize queftions, 95, 102, 103, 220, 3235 325s 326, 424, 425.

Prony on the comparative expanfive force of the fteam of water and
of alcohol, 345.

Quadrupeds, extra& of a memoir on the foflil bones of, 413.

Red, the Turkey or Adrianople, procefs for dyeing, 4, 126.
———______—_____—_-— effe&ts of mordants on, 274.
Red lead of Siberia, 4 new metal found in the, 279, 361.
Red fea, on a junétion of the Mediterranean with the, 128.
Regnier, defcription of the dynanometer invented by, 339.
Requeno’s procefs for encauftic painting, 406,

Roman National Infiitute, nomination of the members, 104,
Rufh, Dr. on the fugar maple, 182.

Sap, experiments on its rifing in trees, mote, 184.

in vegeta'les, prize quettion concerning the, 424.
Saphies, a thort account of them, 241.

Saturn, obfervations by Herfchel on, 60,

Schrader, Profeffor, defcription of his 26 feet telefcope, 113.
Sego, a large city in Africa, fhort detcription of, 23 5.
Senjibility of plants, remarks on the, 305.

Shea-toulou, or tree butter, account of the, 238,

Shreeter’s

j

438, IN DE X.

Shroeter's remarks on the planet Venus, page 59.
Siberia, a new metal found in the red lead of, 279, 361.
Snuff, veffels employed in Portugal for moiftening, 396.
Socoloff’s method to deftroy worms and infects, 169.

Solar and Lunar period of 600 years, on the, 23.

_ Song, tranflation of an African one, 236,

Sounds, experiments to produce by different gafes, 332.
Soy, methods employed in Japan and China to prepare, 342.
Spain, method employed in, for making alcarrazas, 371.
Spallanzani’s experiments on bats, 134.

Spectre of the broken, obfervations on the, 232.

Sponges, on the irritability of, 34.

Stars, on their number and pofitions, 61.

Steam, on the expanfive force of, 345.

Steam engine, account of Mr. Cartwright’s patent one, 1..
Steel and iron, obfervations on, 46.

’ Strength of men.and animals, an inftrument to meafure the,. 399;
Structure of cryftals, theory of the, 35, 153, 287, 376.
Subftitute for oil paint, to prepare a cheap one, 22.
Sugar maple, an account of the, 182, 322.

Sun, on the {pots of the, sg.

Swallow, detcription of the Javanefe, 118.

Sympathetic ink, from, nitrite of zinc, 175.

Tanning, obfervations on the epidermis applied to, 409.

Telegraph, on the invention of the, 312.

———- defcription of Dr. Hooke’s, 314. .

Telefcope, account of the large one at Kiel, 113.

Teft liquors for dete€ting acids and alkalis, 180.

Teylerian fociety, prize queftion by the, 103.

Theory of the firudure of cryftalsy 355.153, 287, 376.

Thornton, Dr. on.a fruit half orange half neétarine, 423.

Time pieces, on the irregularities in their rate of going, occafioned
by magnetifm, 16.

Tradors, metallic, their influence, 2§0.

Tunnel, propofed to be carried under the Thames from Gravefend to
Tilbury, 223.

Turkey or Adrianople red, oriental procefs for dyeing, 4, 126.

———_____—_-——- effets of mordants in the procefs, 274.

Faquelin’s analyfis of the emerald of Peru, 204.
on the new metal called chrome, 279, 361.

Varley, Mr. on the influence of magneti{m on time pieces, 16.

Vegetation, influence of light on, 64.

- influence of oxygen gas on, 109, 224.

Venus, Shroeter’s obfervations on, 59.

Violet dye, which refifts oxygen, acids, and alkalis, 56.

Voyages and travels—Van Braam in China, 85. Cit. Olivier in
Perfia, &c. 108. Mr. Brown in Abyfinia and Egypt, 108.
Mr. Horneman in Africa, 108. Mr. Park in Africa, 235.
Cit, Baudin in America, 111."

~.

Water,

INDE X.

Water, on the gravity of, as affeGted by cold, page 427.

-- on the expanfive force of the fteam of, 345.

- on the manufaéture of veflels for cooling, 371.

Watt, Mr. on tefts for detecting acids and alkalis, 180.

Wedge, on the mechanical power of the, 316,

Weights and meafures, intelligence concerning, 112.

explanation of the French, 245.

Wine, to difcover when it is adulterated with metals, 31.

Worms, to deftroy or drive away, 159.

Writings, experiments to render them indeftrutible by fire, 173.

Wurmb, defcription of the large orang outang by, 225.
obfervations on his account of the erang outang, 337.

439

Yel'ow dye, Aftracan procefs for a, 127+

Zoonic acid, procured from animal fubftances, 68.

END OF THE FIRST VOLUME.

Ee RST A.

Page 3, fi 34, for axles read axes——P. 13 lait Jine, for potafber
and wine fone, read potafh and crude tartar. P. 60, 1. 22, for
12 hours, read 10 bours.——P. 82,1. 18, for- mine, read ore.———~
P. 101, 1. 8 and |. 12, for frontiat, read frontian— P. 145, l. 225
for etber of vitriol, read fulphuric ether.
dated, read oxygenated.—P. 332, line 5, after muriat of, infert
mercury or~—=P. 376, 1. 17, dele the. P. 373 in the note, for
lex, read lilex.

The Binder is defired to place the Plates, in their order, before
the Index, at the end of the Volume.

ve,
*
+
pies

P. 311, 1. 29, for oxy °

a

! 4