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CONTENTS

OF THE

FOURTEENTH VOLUME.

1. A REPLY to Mr. Puayratr’s Reflections on Mr.
Krrwan’s Refutation of the Huttonian Theory of the
Earth. By Ricwarp Kirwan, E/g. LL.D. F.R.S.
and P. R. I._A. - ~ - Page 3

II. An Iluftration and Confirmation of fome Faéts mentioned
in an Effay on the primitive State of the Globe. By
Rionarp Kirwan, E/y. LL.D. F.R.S, and P.R.LA.

14

Ill. An Effay on the Colours obtained from the metallic
Oxides, and fixed by Fufion on different vitreous Bodies.
By ALEXANDER BroGniart, Direétor of the National
Manufaéory of Porcelain at Sevres, Engineer of Mines, Se.

) I
IV. Memoir on Tubes rendered harmonious by Hydrogen Gal
Read before the Society of Phyfics and Natural ‘Bisftory of
Geneva, by G. Devarive, Ex-Prefident of the Royab
Sociely of Edinburgh, and Member of the Medical Col-
leges of London and Geneva SS a: 24
V. On Painting. By Mr. E. Daves, Painter 31
VI. Extra& of a Memoir on Argental Mercury. Read
before the French. National Inflitute, by C. CorpizR,
Engineer of Mines - - - 41
VII. Extraé of a Notice, read in the French National In-
Jlitute, on a new Variety of Epidote., By CHAMPEAUX
and CrEssac, Engineers of Mines - 45
WILL. Note on a Variety of carbonated Lime, found near Port
Seguin, Department of Vienne. By C, Cressac, Engi-
neer of Mines ae A hays 48
IX. Experiments and Obfervations on certain Stony and
Meétalline Subjlances which at different Times are Jaid to
aye fallen on the Earth; alfo on various Kinds of Native
Tron. By Eowarv Howard, EB/g. ERS, 49
X. Conjiderations on Dr. Hurron’s Theory of Rain:
read before the Afkefian Society, in the Seffion 1801-2, By
Luxe Howarp, Ef. FLL. S. aa ry x38
“XI. General Confiderations on Vegetable Extragis. » By
C, PARMENTIER > ‘ee. -*) 63
XII. Defcription of a Three-blaft Fufing Furnace, conftruéted
in the Chemical Laboratory of the French School gf Manes.

Vou, XIV. No. 56. a By

-

CONTENTS.

By P. Tonerur-Narer, attached to the Council of
Mines : as - - 69
XI. On @ metallic Solution, which forms a Yellow Ink,
that appears and difappears like that of Hellot. Read
before the French National Inftitute, by C.-GiLvET-
Laumont, Affciate - . 6
XIV. A fhort View of the Craniognomic. Syftem.of Dr,
GALt, of Vienna. By L.Bosanus, M.D. Member of
the Medical Societies of Jena and Paris, and of the Society
of the Obfervers of Man - = 77
XV. Proceedings of Learned Societies - - 84
XVI. Intelligence and Mifcellaneous Articles - 92
XVII. On Painting, By Mr. E. Daves, Painter 97
XVIII. Odfervations on the Zodiac at Dendera. By the
_ Rev. Samuey Hentey, F.S.A. - 107
XIX. Memorandums, Hints, Precepts, and Recipes, for
the Ufe ee Artifts, Manufaéturers, and others ; including

~ various fort Proceffes either mew or little known 117
XX.: On a new Method of making Cement for Terraces; and
the Ufe of liquid Pitch to render them impermeable to Water,
and fecure from the Atiacks of Froft. By CasiIMiR
‘PuyMAURIN - - - 125
XXI. A fhort View of the Craniognomic Syflem of Dr. GALL,
of Vienna. By L.Bosanus, M.D. Member of the Me-
dical Societies of Jena and Paris, and of the Society of the
Obfervers of Man - - = 131
XXII, Letter from Count Morozzo to C. LacerEpeE,
Senator and Member of the French National Inflitute, on
‘an Ichneumon brought from Egypt - 139
XXIII. Of the State of Vapour fubfifting in the Atmofphere.
By Ricwarp Kirwan, E/g. LL.D. F.R.S. and

OO Ph. tia. i > - 143
XXIV. Some Conjeétures refpefting ihe Origin of Stones
which have been obferved to fall from the Clouds. By
WitiiaM Beauronrn, 4. M, - = 148
XXV. On the Hydrometer, By WitttaM SpPxER, E/g.
Supervifor and Affayer of Spirits in the Port of Dublin 151
XXXVI. A Short Account of the Mammoth. By Mr. Rem-
BRANDT PEALE - - - 162
XXVIT. New Theory of the Conftitution of mixed Gafes elu-

__cidated, By J. Datton, E/y. 169
XVI. Proceedings of Learned Societies - a2" .
XXIX. Intelligence and Mifcellaneous Articles - 180 -

XXX. On Capillary Aélion, By Joun Lusiiz, Ef.

. 193
BAX, OMMervations on the Salt of Bitumen; the AR Nee
~ ae

CONTENTS.

5

of the Hindoos. By Joun HENDERSON, Efg. Surgeon
on the Bengal Eflablifhment = 4 206
XXXII. Memoir on the Refining of Lead ; with fome Reflec~
tions on the Inconvenience of A/b Cupells; and the De/crip-
tion of a new and economical Method of conftruéting Cupells
or Refining Vefféls: read in the French National Inftitute.
By C. DUHAMEL, Member of the Inftitute and Infpeéior
of Mines . - - - - 210
XXXIII. On Painting. By Mr. E. Dayns, Painter 218
XXXIV. On the Differences which exift between the Heads
of the Mammoth and Elephant. By REMBRANDT
PeaLe, F/g. ie aire ani ee = 228
XXXV. On the Hydrometer. By Witi14M SrzER, E/g.
Supervifor and Affayer of Spirits in the Port of Dublin 229
XXXVI. Memoir on the’ Supply and Application of the Blow-
pipe. By Mr. Ropert Hare gun. Member of the
Chemical Society of Philadelphia - 2.38
XXXVII. Memoir on the Fatrication of Charcoal in the
Foreft de Renon, near Rochelle. Addreffed to the French
Council of Mines, Nivofe 30, Year 10. By C. FLEURIAU-
BELLEVUE - - - 245
XXXVIILI. On the Northern Magnetic Pole of the Earth.
By JERoME LALANDE -. - 249
XXXIX. Of the State of Vapour fubjifting in the Atmo/phere.
By Ricuarp Kirwan, Eg. LL. D. F.R.S. and
P.R.T..A. - - - 251
XL. Report, read before the Conference of Mines, on the
Specific Gravity of the Coals of Jeveral Mines of France;
and on the Difference in the Increafe of Volume awhich they
acquire by Humefation. By C. BuAvIER, Engineer 258
XLI. Memoir on the War-Tree of Louifiana and Pennfyl-
vanja. By CHanves Louis Caper, of the College of
Pharmacy - - aes - 262
XLIL. Proceedings of Learned Societies. anise S209
XLII. Intelligence and Mifcellaneous Articles. - 285
XLIV. Analyfis of the Schicferfpath from Cornwall; to which
is prefixed an Analy/fis of Carbonated Lime, and Remarks on
the Means which bave been employed to afzertain the Quan-
tity of Carbonic Acid contained in it, By Mr. Ricuanp
PirtuLies, Member of the Briti/h Mineralogical Society 289
XLV. Defeription of sthe Schieferf{path. By ARTHUR
Alkiny E/g. Member of the Briti/h Mineralogical Society

| 293
KLVI. A fhort, Account of Mr, Smipw’ si din-pump Vapour-
bath. By Mr. Henry James - - 293

XLVI. Memdir on the Supply and Application of the Blow
pipe.

CONTENTS

pipe. By Mr. Ropert Hare jun. Member of the
Chemical Society of Philadelphia - - 293 |
XLVILI. On the double Refraétion of Rock Cryftal, and an-
- other dioptric Property of that Mineral Subjtance. By C. P.
Tore“ DE NaRct, attached to the Council of Mines pW

XLIX. Preparation of the as sonal of Lime. By PR.
Van Mons 309
L. Chemical Analy/is if an uncommon Spoeide of Zeo-
lite. By Rospert Kennepy, M.D. F.R.S. F.A.S.,
and Member e the. istag eee of Pigpitenn Edin-
burgh Io
LI. En vperiments balpetiolg the Ation of ‘fome lately d sehen
Metals and Earths on the sede ick Matter of Cochineal.
By M. HERMSTAEDT - - 316
Li. On the Manner of Hunting and Sporting by the Englifb
in Bengal. By Colonel G. TRONSIDE - 319
LIL Odfervations upon the Monjfoons, as far as they regard
the Commerce and Navigation of the Port of Bombay 328
LIV. Method of obtaining inodorous Benzoic Acid. ‘By
M. F. Giese - = - 331
LV. On the Mammoth. By Governor PowNALL. 332
LVI. Remarks on the amg State whee tae By Mr.
G. J.WRiGHT 337
LVI Il: Ewtradi from a Memoir on the. Prapertiens of Yitria
Earth compared with thofe of Glucine; on the Foffils in
which the for mer of thefe Earths 1s contained; and on. the
Difcovery of a new sa i of a Metallic Nature. By
A. G. EKEBERG 346
LVIII. Obfervations on the Olinge wick Gon Bornib Acid Gas
experiences oy the Electric Spurk, cnd on the Deccmpofition
of the fame G.s by rei al Gas. By par ban DE
“y aeeepe 350
LIX. Some Account of Riowa RD Kinwaxy Eq. LED:
F,.R.S. and P. RI. A. - 353
LX. Ob/fervations on the Law of the iytosfien of Water at
Temperatures below 42°; extracied from a Paper on the
Power of Fluids to conduét Heat. By Joun DAtToNn
35
LXI. Remarks on certain Properties of Barytes in its a
bination with Mineral Acids; and on iwo new Salts never

before deforibed. By J. Hume, E/q. L ,WLALRS7
LXII._ On the Uiility of Pruffiate ts ee as a Pigment.
By Cuarres Harcuer, P/g. PLR. S. 359
LXIIL. Proceedings of Learned Socie fies a 360

LXIV. pymea aud Mycellaneous Articles = 363

THE
PHILOSOPHICAL MAGAZINE.

I. A Reply to Mr. Puayratr’s Reflections on Mr. Kir-
wan’s Refutation ‘of the Huttonian Theory of -the Earth.
By Ricwarp Kirwan, E/g. LL. DF. R.S. and
PAR TO

DEAR SIR, Dublin, Aug. 24, 1802.

W HEN I firft undertook to ftate fome objections, to
Dr. Hutton’s Theory, I little imagined I fhould call forth
fuch indignation and fuch illiberal perfonalities as appeared
in.the fecond edition of that work; but however hurt the
felf-love of an author might have been by an attack on his
favourite ideas, I had ftill Jefs reafon to forefee that the fame
ftyle of hoftility would, have been perfifted in by any perfon
to whom I had given no offence whatfoever. Mr. Playfair’s
Iluftrations of the Huttonian Theory, which [£ have feen
only a few days ago, convince me I was miftaken; be not
only attempts to. juftify the @/perities, as he calls them, of
Dr. Hutton, but aggravates them by new invectives. You
need not fear, Sir, that I fhall pollute the pages of your
journal by the vuigar mode of retaliation ; I {hall make no
reflections on his defence of Dr. Hutton’s Theory : enough
has been faid on that fubjeét. I fhall content myfelf with
repelling his unprovoked and unmerited attacks on myfelf,

To etleét this, however, I fhall be obliged to ftate his
abufive paragraphs, and thus expo! their indecency. It is
the only vengeance I fhall take; he, probably, will account
it none,

Page 119. “ To affert, that in the economy of the world
we fee no mark either of a beginning or an end, is very dif-
ferent from affirming, that the cite had no beginning, and
will have no end. The firft is a conclufion jutiitied by com-
mon fenfe as well as found philofophy; while the fecond is
a prefumptuous and unwarrantable affertion.”’ Here | mutt
deny that the firft affertion, namely, that we fee no mark of
a beginning, is a conclufion juftificd by common fenfe and
found philofophy,

No, LIL. A2 Mr,

4 A Reply to Mr. Playfair’s Reflections om

Mr. De Luc, Sauffure, and Dolomieu, were not deficient
either in common fenfe or found philofophy, yet they all
affert that we may difcover evident marks of the beginning
of the world in its prefent ftate: nay, Dr. Hutton himfelf
allows it, for he judged the aétual world to have proceeded
from a preceding, and afferts that it will have an end. What
Mr. Playfair muft then mean is, that we can fee no trace of
the beginning of this fucceffion of worlds. Of fuch fucceffion,
it is true, we can trace no beginning, becaufe it is merely ficti-
tious: but while Dr. Hutton afferted the reality of fuch a fuc-
ceffion without affigning any limit, it, was natural for me,
who was totally unacquainted with him, to infer that he
really judged it to have no beginning: this conclufion was
fo natural, that it occurred to others long before I had written
on this fubje&t. Mr. Williams, his countryman, who was
probably acquainted with him, fays, ‘* That Dr. Hutton aims
at eftablifhing the belief of the eternity of the world, is evi-
dent from the whole drift of his fyftem, and from his own
words; for he concludes his fingular Theory with thefe fin-
gular expreffions : ‘ Having in the natural hiftory of the earth
feen a fucceffion of worlds, we may from this conclude that
there isa fyftem in nature—in like manner as, from feeing the
revolutions of the planets, it is concluded that there is a
fyftem by which they are intended to continue thefe revolu-
tions. But, if the fucceffion of worlds is eftablifhed in the
fyftem of nature, it is in vain to look for any thing higher
in the origin of the earth. ‘The refult, therefore, of our pre-
fent epee is, that we find no veftige of a beginning, no
profpeét of an end.’’’—Williams’s Natural Hiltory of the
Mineral Kingdom, Preface, Ix. ;

Now, I aik what can be the meaning of thefe Jaft words, |
it is im vain to look for any thing higher in the origin of the
earth. Higher than what? Is it not plain that the meaning
is, higher than that eftablifhed fucceffion, of which fucceffion
we can trace no beginning? And what is a fucceffion of which
we can trace, and to which we affign, no beginning? Now
Dr. Hutton, in his firft edition, no where mentioned that it
had a beginning, though fuch beginning were not apparent
on bare infpeétion of the a€tual world; was not then his
meaning at leaft ambiguous?

So alio Mr. Howard, in his learned work on the Struéture
of the Earth, p. 549, fays: ‘* Dr. Hutton rejects all time,
the operations of his living renovating nature {corn all limits:
time (fays he), which meafures every thing, is to nature
endlefs and nothing.” But to return to Mr. Playfair:
** Mr, Kirwan, in bringing forward this rafh and ill-founded

Sis cenfure,

Mr. Kirwan’s Refutation of thé Huttonian Theory. 5

cenfure, was neither animated by the fpirit nor guided by
the maxims of true philofophy. By the fpirit of philofophy
he muft have been induced to reflect, that fuch poi/oned wea-
pons as he was preparing to ufe are hardly ever allowable in
{cientific conteft, as having a lefs dire&t tendency to over-
throw the fyftem than to hurt the perfon of an adverfary, and
to wound, perhaps incurably, his mind, his reputation, or
his peace.” This fevere cenfure appears to me unmerited :
of its liberality I leave others to judge. The mention of pre-
paration of poifoned weapons is perfeétly rifible, when it is
confidered that the whole argument is comprehended in ten
or twelve lines. If Dr. Hutton had lived either in Spain or
Portugal, fome hurt to his perfon might indeed be appre-
hended ; but in Britain, where Mr. Hume, with impunity,
trefpaffed much more on the received religious principles, no
danger could rationally be fufpected ; and it were idle to think
that the reputation of an author could any more be wounded
by an inference obvioufly deducible from his principles, than
by his own ftatement of thofe principles.

Mr. Playfair continues: ¢¢ By the maxims of philofophy
he (Mr. Kirwan) muft have been reminded, that in no part
of the hiftory of nature has any mark been difcovered either
of the beginning or end of the prefent order.” This I deny,
in common with thofe eminent geologifts already mentioned :
clear traces of a beginning are found. < By attending to
thefe confiderations Mr. Kirwan would have avoided a very
illiberal and ungenerous proceeding; and, however he might
have differed from Dr. Hutton as to the ruth of his opi-
nions, he would not have cenfured their tendency with fuch
rath and unjuftifiable feverity.”” I never once confidered the
tendency of his opinions, but merely their direét confe-
quences; I had nothing to do with their tendency in & mere
geological treatife. SY

Page 143. ‘‘ It has been afferted that Dr. Hutton main-
tained all calcareous matter to be originally of animal forma-
tion: this pofition, however, is fo far from being laid down
by Dr. Hutton, that it belongs to an inquiry which he cares
fully avoided to enter on.”

Page 147. * It is neverthelefs true, that Dr. Hutton
fometimes expreffed himfelf as if he thought that the prefent
calcareous rocks are all compofed of animal remains: this
conclufion, however, is more general than the facts warrant,
and, from fome incorreétnefs or ambiguity of language, is
certainly more general than he intended.’ Yet, p. 156,
treating of my account of the origin of coal mines, be pie
A 4 “ t

6 A Reply to Mr. Playfair’s Reflettions on

“Tt is indeed worth while to compare what is faid concerning
the degradation of mountains in the above quotations (from
my Geologi¢al Effays) with what is advanced concerning
their indeftructibility in another paffage of the fame volume,
namely, all mountains are not fubject to decay ; for inftance,
fcaree any of thofe that confift of red granite, &e, One can
be at no lofs about eftimating the value of a fyftem in which
fuch grofs inconfiftencies make a neceffary part.” Mr. Play-
fair then finds a grofs inconfiftency in maintaining that fome
mountains are fubjeét to decay, though a// mountains are
not; faéts proved beyond the reach of contradi€tion; but he
can fee none in his own two paragraphs.
Page 157. * The quantity of hornblende and filiceous
{chiftus neceffary to be decompofed in order to produce the
coal ftrata prefently exifting, ts enormous. It is true that
Mr. Kirwan, never at all embarrafled about preferving # fimi-
litude between nature as fhe now is, and as fhe was hereto-
fore, lays it down, that the part of the primeval mountains,
which is worn away, contained much more carbon than the
part which is left behind: this, however, is an arbitrary fup-
pofition.”’” Not quite arbitrary neither. Mountains before
the flood muft have been in many refpeéts differently cir-
cumftanced from the prefent; and if at prefent, after attam-
ing their utmoft late of confolidation, many of them are in
a {tate of decay, much more liable to it muft they have been
then. Hornblende and filiceous fehifti are not the only
ftones that contain carbon, nor are the mountains that pre-
fent thefe rocks the only mountains that contain veins of it :
many granite mountains alfo prefent them. Mr. Playfair,
indeed, pays little regard to the authorities I adduce to prove
the facts J allege; more impartial readers may poftibly pay
more.
I thall therefore quote one entitled to the higheft credit.
Citizen Haiiy, in the third volume of his Mineralogy, p. 308
_and 3009, tells us that anthracite (native mineral carbon loaded
with ftony matter) belongs exclufively to primitive countries,
and that the obfervations of Mr. Dolomieu prove the exift-
ence of carbon independently of animals and vegetables ; and.
that anthracite was, he prefumed, nothing more than pure
carbon, affociated, by accidental caufes, with a certain quan-
tity of iron and filex. And Mr. Duhamel has fhown in a
miemoir, approved by the Academy of Sciences, that the ar-
gillaceous //rata that intercede beds of coal are formed of the
etrites of the neighbouring mountains: Journal des Mines,
vill, p. 403 and Haiiy, iii, p.319. My fyflem is not then
: : quite

’

Mr. Kirwan’s Refutation of the Huttonian Theory. 9

quite original, in the farcaftic fenfe in which Mr. Playfair ap-
plies this word ; but it is evident irritation was his fole purpofe.

Mr. Playfair adds, ‘“ We may allo obje& to Mr. Kirwan,
that the filiceous part of the mountain has not been chemi-
cally diflolved ; it has only been abraded and worn away.
Mechanical action has reduced the quartz to gravel and fand,
but has not’ produced on it any chemical change; the car-
bon, therefore, could not be fet loofe.”” Mr. Kirwan has not
affumed, that carbon was fet loofe from quartz, though it
might have been from filiceous fchifti and other compound
{tones and rocks: difintegration is often effected by decom-
pofition; thus felfpar is converted into argil and filiceous
particles in many inftances; but this more frequently hap-
pens to ftones that contain iron. J:

Page 158. Mr. Playfair, objecting to ftrata formed by
tranfudation, aks what occupied the fpace of the coal bed
before the tranfudation from the upper part of the mountains,
The queftion is unfair, and very fimilar to the numerous dif-
ficulties objected to Dr. Black’s difcovery of fixed air, before
its truth was generally acknowledged. A faé is often dif-
covered, though the mode of its production be unknown; yet
in this cafe the queftion is eafily anfwered: the carbonic
part of the coal in the mountain of St. George’s here alluded
to was formed before the upper part of the mountain was
formed; itis only the bituminous ingredient that fubfequently
tranfuded from the fupervenient fuperior firata; and I fup-
pofe it will be admitted that petrol might penetrate and coa-
lefee with the carbonaceous part, without floating the upper
part of the mountain, as Mr. Playfair ludicroufly fuppofes.
This account is fo much the more probable, as this moun-
tain is formed of a mixed calcareous fione abounding in areil ;
and this fpecies of calcareous ftone is of fecondary formation,
as Mr. Haffenfraz, the author of this memoir, truly remarks,
p- 266.

Mr. Playfair concludes by remarking, ‘ that fuch reafon~
ing is fo great a trefpafs on every principle of common lenfe,
that to beftow any time on the refutation of it, is, in fome
meafure, to fall under the fame cenfure.”

Page 171. ‘* If any one afferts, as Mr. De Luc has done,
that fand is a chemical depofit, a certain mode of eryftalliza-
tion which quartz fometimes affumes, let him draw the line
which feparates fand from gravel; and Jet him explain why
quartz in the form of fand is not found in mineral veins, in
granite, nor in bafalt; that is, in none of the {tuations where
the appearances of cryfallization are moft general and beft
afcertained.””? What. is meant by a chemical depy fit, I do not
Ag underftand;

3 A Reply to Mr. Playfair’s Refleftions cn

underfland; but that fand is fometimes found regularly. cryf+
tallized is evident, for a whole ftratum of fuch fand has been
found at Neuilly: to expect that a fubftance expofed to end-
lefs friction fhould always be found in regular cryftals would
be extravagant; that of Neuilly was therefore formed on the
fpot in which it was found.—A vein filled with fand has been
found among the mines of Peregruba in Siberia. Renovantz,
a ag xiii. Gravel and fand differ only in fize, and to
expe@ either in granite rocks would be inconfiftent; but on
and befide granitic mountains gravel very frequently occurs.
The cryftallization of bafalts is fo far from being afcertained,
that, on the contrary, it has been demontftrably proved that
bafaltic prifms are not cryftallized, by thofe that have paid
moft attention to this fubjeét.—Romé de Lifle, 1. p. 4395
Haiiy Miner. iv. 476.

Page 180. ‘* The Neptunift, who has provided the means
of diffolving the materials of the ftrata, has only performed
half his work, and muft find it a tafk of equal difficulty to
force this powerful menftruum to'part with its folution. Mr.
Kirwan, aware, in fome degree, of this difficulty, has at-
tempted to obviate it in a very fingular way. Firft, he afcribes
the folution of all fubftances in water, or in what he calls
the chaotic flid, to their being created in a ftate of the moft
minute divifion. Next, as to the depofition, the folvent be-
ing, as he acknowledges, very infufficient in quantity, the
precipitation took place (he fays) on that account the more
rapidly. If he means by this to fay, that a precipitation
without folution would take place the fooner, the more in-
adequate the menftruum was to diffolve the whole, the pro-
pofition may be true; but, it will be of no ufe to explain the
eryftallization of minerals (the very objeét he had in view),
becaufe to cryftallization it is nota bare fubfidence of par-
_ ticles fufpended in a fluid, bat it is a paffage from chemical
folution to non-folution or infolubility that is required.’

.. My meaning is clearly ftated in pages 10 and 11 of my
Geological Eflays, that the folids contained in the chaotic
fluid were not diffolved by that fluid, but were contained in
that ftate of minute divifion to which, if the fluid could of itfelf
diffolve them, they would be reduced; and that, if the quan-
tity of that fluid were infufficient to hold them in folution,
this circumftance’ would haften their cryftallization, precipi-
tation, and depofition, refpectively. I did not aflert that the
folution was effected by the menftruum, but, on the con-. .
trary, denied it. Mr. Playfair’s affertion, that cryftallization is
a paflage from chemical folution to non-folution or infolu-
bility, is denied by Bergman: ‘ Sed non tantum vere foluta

im

Mr. Kirwan’s Refutation of the Huttonian Theory. 9

tu aqua determinatas acquirunt formas, verum etiam ni_fallor
Jatis attenuata.” Beraman, il. p. 15. It is fufficient that the
particles fufpended and fufficiently attenuated have an affinity
to each other.

Page 22. <¢ Barytic earth is well known to have a ftronger
attraction to fixed air than common calcareous earth has, fo
that the carbonate of barytes is able to endure a great degree
of heat before its fixed air is expelled : accordingly, when ex-
pofed to an increafing heat at a certain temperature, it is
brought into fufion, the fixed air ftill remaining united to it:
if the heat be further increafed the air is driven off, and the’
earth lofes its fluidity.” And, p. 185, “ Carrara marble may
require a heat of 6300° of Wedgwood to melt it in the open
air; but under fuch a preffure as would retain this gas it
cannot be inferred that it might not melt with the heat of a
glafshoufe furnace. ‘Jn like manner it may be true that 280
cubic inches of air acting on charcoal cannot effect the fufion
ef one grain of this marble after its fixed air is driven off
from it; but we cannot from thence draw any inference ap-
plicable to a cafe where the carbonic acid is retained, and
where the action of heat is independent of atmofpheric air.”
Now, in no experiment with which I am acquainted has na-
tive aérated barytes been fufed without the expulfion of its
air, or union with the earth of the crucible. Dr. Hope, in-
deed, fufed it in a black Jead crucible, but found it loft 23 per
cent. nearly of its weight; which is the whole, or nearly fo,
of the air contained, and accordingly it made but a very flight
effervefcence with marine acid. Hence the pofition laid
down, p. 22, that barolite or native carbonate of barytes
may be fufed and ftill retain its fixed air, is founded on no
experiment; but from all known experiments the contrary
inference is fairly deducible with refpeét to it, as well as with
refpect to Carrara marble; nor is there any reafon to think
that a lower heat, independent of the atmo{phere, could have
any other effect.

Page 201—203. The fact alluded to, namely, that thells
are found incorporated’ in the body of a rock at a great height
near Guancavelica, I have fully fated and explained in a dif-
fertation long fince printed, and which’ accompanics this
letter ; to which I fhall therefore beg leave to refer *.

Page 242. “‘ Mr. Kirwan, in order to account for the
maguitude of matles of iron found in Siberia and Peru, fap-
pofes that {mall pieces of native iron have been originally
agglutinated’ by petrol: this is, no doubt, the moft fingular
eT all the opinions advanced on the fubjeét; and, as it bor-
* See the next article in the prefent Number.—Evir.

Tows

to A Reply to Mr. Playfair’s RefleBions on

rows nothing from analogy, it admits of no proof and re=
quires no refutation.” I was, however, led into this opinion
by analogy with Mr. Gadd’s experiments in the 32d volume
of the Memoirs of Stockholm; for he tells us, that if clay
and calces of iron be plentifully mixed with oil, they will
form a mafs which will harden even under water. If Mr.
Playfair were acquainted with Mr. Chladni’s opinion, that
thefe maffes were fragments of a broken planet that fell within
the {phere of attraction of our globe, he might poffibly think
- it the moft fingular; yet even fo, it is probable he would
not facrifice the pleafure of beftowing that drftinguifhed epi-
thet on mine. However, as he judged my conjeéture, I
know not on what foundation, inconfiftent with the princi-
ples of chemical fceience, I have mixed ruft of iron with pe-

trol, and afterwards with petrol to which falphur was added,
and found it difpofed to coalefce in a few days. ‘
P. 422. * One of Mr. Kirwan’s objeétions to the depofi-
tion of materials at the bottom of the fea is thus ftated :—
€ Frifi has remarked, in his mathematical difcourfes, that if
any confiderable mafs of matter were accumulated in the
interior of the ocean, the diurnal motion of the globe would
be difturbed, and confequently it would be ue oes
The appeal made here to Frifi is fingularly unfortunate, as
that philofopher demonftrated the contrary to Mr. Kirwan’s
pofition. ‘The inftance juft given may ferve as one of many
to fhow what confidence is to be placed in that undigefted
mafs of faéts and quotations which Mr. Kirwan, without
diferimination and without difcuffion, has brought together
from all quarters.” Mr. Playfair might, however, eafily
infer, from the loofe manner in which Frifi is quoted,
(namely, in /ome of his mathematical treatifes, fo different
from my ufual manner, in which the page I take from is
mentioned,) that I had not that author before me; and, in
fact, I took it from Mitterpacher’s Phyfical Defcription of
the Earth, p. 25, who fays, that according to Frifi, in the
cafe above mentioned, the velocity with which the centre of
the globe would move would be increafed; omitting the

calculation’ and the mention that the increafed velocity
would not be /exfble for a long period of years. I hope —
therefore it is the only one out of the many quotations I
have made in which any miftake can be found: if Mr. Play-
fair could find any other, he doubtlefs would bave mentioned
it. The attempt to weaken the force of the numerous faéts
I colleéted, adverfe to the Huttonian theory, by calling them
au undigefled mafs, is curious, and, if allowable, would fur-
nifh a very convenient and expeditious method of getting rid
Q

Mr. Kirwan’s Refutation of the Huttonian Theory. %%

of them, but will not, T prefume, appear perfectly fatisfac-
tory to an impartial public.

Page 427. The fact relative to the deltas formed in the
mouth of the Bourampeuter Mr. Playfair thinks I have mif-
apprehended, becaufe major Rennell does not affert that
rivers employ a// the materials which they carry with them,
and deliver none into the fea. On the contrary, [ think, they
carry many of them into the fea, but not to any great di-
fiance, much lefs into its unfathomable depths, as Dr. Hutton
afferts. The fact relative to the extenfion of coafts is now fo
well known to all modern geologifts, that it were tinze foft to
dwell longer on it: that the deltas themfelves are diminifhed
by particles detached from them, and carried into the recefles
of the deep, is a remark which I do not recollegt to have
met with; but in fome inftances, where they confift merely
of fand, they are often diminifhed by the winds: that even
the argillaceous particles are not carried far into the fea, may
be feen in Morfe’s American Geography, p. 49, Irith edition.

I decline entering into any further difeuffion of Mr. Play-
fair’s replies to fome other objection made by me to the Hut-
tonian theory. The intelligent reader will mect with many
confident and arrogant aflertions of which he probably will
require fome proof, as in p. 481 and 482; many that are
perfectly unfatisfactory or even contradictory, as where he
allows that the impulfive motion of the waves againft the
fhores is greater at a /mail diftance from them, and yet af
ferts that the detrites of the fhores are conveyed to a great
diftance. He alfo affirms with great confidence, that as the
flowing of the tide requires jult fix hours, and the ebbing of _
it alfo fix hours, the quantity of matter moved, and its velo-
city, muft be juft the fame: p. 432. In the abftract this is
certainly true, and in the middle of the ocean; but in moft
harbours the contrary happens: thus La Lande tells us that
in the harbours of Breft, Dunkirk, Bordeaux, and Rouen, the
ebb tide is about a quarter and often half of an hour flower
than the flow: vol. iv, p.117. Thefe exceptions, I am
perfuaded, he is well acquainted with; but his burry and
impatience * (if I may be permitted to ufe his own expref>
fions) to combat my affertions Jed him to ‘overlook them,
He is much at a lof to account for the remains of elephants
and of the rhinoceros found in Siberia, and thinks it moft
probable that they belonged to antient fpecies of thofe ani- —

* Thefe are the caufes to which he afcries the many miftakes he fup-
ES me to have committed in combating the Huttonian theory; to rea-

@ he thinks me incapable.
mals

x2 A Reply to Mr. Playfair’s Reflections on

mals that could endure the feverity of a Siberian winters
p- 475. If I had advanced fuch an opinion, it is probable
he wonld be equally at a lofs to find an epithet fuficiently
fevere to f{tigmatize it.
P. 481. It is evident, he favs, that my geological writings
are the work of a man who has not feen nature with his
own eyes. This, I fuppofe, he infers from the total abfence
of obfervations made by myfelf. It is however pretty no-
torious here, that I have vifited, traverfed, and examined,
moft of the numerous mountains in this country; but I
thought that in a controverfy of this nature, the teftimonies
ef perfons who had taken no part in it, and who had feen
much more than I have, would be more effectual and con-
vincing: it is much eafier to vilify my writings than to an-
{wer them.
No abfurdity appears to Mr. Playfair fo great as the at-
tempt to connect the Mofaic hiftory of the creation of the
earth with any philofophical inquiry concerning it: this at-
tempt he thinks injurious both to the freedom of philofo-
phical inveftigation and to the dignity of religion: p. 477.
The text of Mofes he thinks covered with a veil which can-
not be torn off, and mutt be confidered as if it never exifted :
p- 478. Yet in other parts of his work he feems himfelf
fenfible of the extravagance of this affertion taken in the moft
extenfive fenfe, p. 126; he feems to limit it to the age, figure,
and motion of the earth; which no geologift ever pretended
to infer from the Mofaic text, in which no mention of them
/is to be found, no more than they have the explanation of
the aét of creation itfelf; a motion which he alfo unjufily
* afcribes to them: but the feries of events which took place
after the creation of the earth, are too plainly mentioned to.
be overlooked or mifunderftood: to fay that this account is
fo obfcure as not to be intelligible, is tantamount to faying
that it is ufelefs. It was never pretended that Mofes: in-
tended to write a treatife of geology, any more than that
Greek or Latin hificrians intended to give a treatife of aftro-
; nomy from their occafional mention of eclipfes or comets ;
nor is the genuine philofophical inveftigation of thofe pha-
nomena any more impeded in one cafe than in the other:
‘ on the contrary, due notice is taken of their accounts by all
| aitronomers. But there is a fpecies of inveftigation, abufively
7 called philofopbical, which abftraéts from hittorical accounts
either of the creation or of the flood, as if the accounts,
given of both by Mofes were unworthy of credit: to this
objection the Huttonian theory is certainly liable, though I

9 never

Mr. Kirwan’s Refutation of the Huttonian Theory. 13

never charged it upon it: fo far was I from wifhing to make
ufe of what Mr. Playfair called poifoned weapons, as he un-
juftly accufes me of having done. .

Tt is in vain Mr. Playfair feeks to compare geology with
aftronomy and zoology; neither of thefe fciences requires any
notice to be taken of the original conftitution of their ob-
jects, their actual ftate beg very nearly the fame as their
primordial ftate: but, where hybrid {pecies occur, their origin
never fails of being attended to.

In geology, the cafe is very different: here we meet with
objects whole original {tate muft have been very different from
their aétual ftate. Rocks or ftones prefenting regular forms
muf{t of neceflity have been originally in a flate from which
fuch forms could arife. Maffes now hardened into -ftone,
but prefenting the impreffions either of vegetables or of other
ftones, muft have been originally in a foft tate. Caleareous
ftones filled with fhells muft have been originally in a flate
fitted for the admiffion of thofe fhells; hence geologifts ne-
ceffarily recur to’a ftate of inanimate nature prior to the pre-
fent. This is admitted by Dr. Hutton as well as by Nep-
tunifts ; but he thinks the prefent ftate to have originated
from a gradual deftruétion of a former, as that did from a
fill more antient : {till the moft antient of thefe worlds either
refembled the prefent, or it did not: if not, we can fay no-
thing of its if it did, the fame difficulties muft occur, and
atinfetuen ty its primordial {tate muft have been different
from its fubfequent fiate, as this ftate is fuppofed to have been
fimilar to the prefent. The cryttallized or foft ftate of our
prefent recks Dr. Hutton thinks proceeded from an igneous
tufion of the materials of a prior world: but he cannot fup-
pofe this of the firft of thefe worlds; its fimilarity with ours
mutt therefore be otherwife accounted for.

I fhall here conclude my obfervations on Mr. Playfair’s
obfervations. Controverfies managed as this has been by
hint and Dr. Hutton, whofe favourite method of anfwering
objections confifts in depretiating or {neering at the under-
ftanding, and undermining the credit of their author, are a
difgrace to philofophy, and fufficiently expofe the weaknefs
of the caufe that obliges to have recourfe to fuch expedients.

$am, &c. &c.
Mr, Tillogh, Ricuarp KIRWAN,

Il. An

Lage

IY. An Wuftration and Confirmation of fome Facts mentioned
in an'Effay on the primitive State of the Globe. By
- Riewarp Kirwan, E/y. LL.D. F.R.S. and P.R.I_A.

Turre is a remarkable fact ftated in this effay, with
refpe&t to which the Mofaic account is fully at iffue with the
moft plaufible of the lately deviled philofophic theories of the
primitive ftate of the globe, namely, the emerfion of fome
portion of land from the primeval ocean previous to the crea-
tion of fifth: Mofes exprefsly affirming, Buffon, the anony-
mous. author of L’Hi/toire du Monde primitif, and many
others, exprefsly denying it. In proof of the Mofaic ac-
count, I alleged that no petrifaGtions were found imbedded
and incorporated in mafles of {tone in fuch countries as were
elevated 8500 or gooo feet above the actual level of the fea—
for inftance, in the great Tartarian platform and the elevated
regions of Siberia—though in all inferior regions of the fame
extent fuch petrifactions were abundantly found, at leaftjiu
limeftones; but even in thefe none were found in thofe ele-
vated tracts, as I proved by the teftimonies -of all the philo-
fophic travellers who have traverfed and examined them.
Bonguer and Don Ulloa* atteft the fame fact with refpect
to Quito and the lofty regions of South America, haying
met with none in ninety leagues from a little north of the
equator, to Cuenca, between 2° and.3° fouth of it, Quito
being elevated 9374 feet above the level of the fea, I even
doubted whether the petrifactions found by Mr. De Luc on
mount Grenier, at the height of 7800 feet, were incorporated
in the body of any ftony mafs; but he has fince affured me
that they were: now the fhells he found being coraua am-
monis, a fpecies of thofe called pelagic, it would thence
appear that the fea had rifen full higher, though not above
1000 feet.
To repel this proof of the Mofaic account, it has been
replied by the laborious, learned, and cloquent writer of
L’ Hifloire du Monde primitif, and others, that the keen air
exifting in thefe elevated regions had long ago decompofed
and confumed the fhells that might have been there depos
fited; but, as the ftones ftill remain, it is evident that the
{hells incorporated in their fhterior muft alfo have remained,
if any fuch were ever contained in them. .
However, it is infifted that petrified fhells have been found
at a far fuperior height to that which I flated as the higheft
* Bouguer, Figure de la Terre, p. 65. Don Ulloa, Mem, Philofoph.

vol. 1. p. 363+ ee
6 limit

Dr. Kirwan on the primitive State of the Globe. 18

fimit. at which they could be found, namely gooo feet, for
that thofe which 1 quoted as proofs of a fubfequent deluge,
found, according to Don Ulloa, at the height of 14,220 feet
in Peru, were in reality petrified. To this account, as it was
only a hearfay report of Gentil, who had it from Don Ulloa,
I own I did not give full credit; at leaft I thought the cir-
cumftance of their having been petrified and imbodied in a
rock not probable: fince that time I have met with a work,
compofed by Don Ulloa himfelf, entitled Mémoires Philofo-
phiques, Hiftoriques et Phyfiques, in the firft volume of which,
p- 34 and 364, the faét of the fhells being petrified and im-
bodied in a rock is fully ftated and confirmed: but 1 fhall
here fatisfactorily prove that the height at which they were
found did not exceed, nor even equal, gooo feet above the
level of the fea; and, fecondly, that they were left there by
a deluge that fueceeded the emerfion of land from the pri-
mizyval ocean.

Firft, Gentil tells us, Mim, Par. 1771, p. 439, in 8vo.,
that thefe fhells were found on a mountain near Guancave-
lica, a fmall town or village between 12° and 13° fouth lati-
tude, which mountain, he fays, is far from being one of the
higheft of the Cordelieres; and that on the {pot in which
the fhells were found, the mercury in the barometer ftood at
the. height of, 17 inches one line and 4 == 17,103 inches;
from which he infers that this fpot was elevated 2200: toifes
over the level of the fea, = 13,869 Englith feet. This height
I fhall now fhow to have been fallely eftimated.

Don Ulloa tells us, p. 34 of the abovementioned work,
and Gentil repeats after him, that, at the village of Guanca-
velica, near but fomewhat below this fpot, the mercury ftood
at the height of 18 inches one line and half. Now Bouguer,
Figure de la Terre, p. 36, exprefsly fays that Quito is ele-
vated from 14 to 1500 toifes only over the level. of the fea,
and is the higheft izbadbited part of the globe: Guancavelica,
therefore, which is inhabited, and mutt have been well known
to Bouguer, cannot be fo high as Quito. Quito was geo-
metrically meafured, Guancavelica was not,

Bouguer alfo tells usy zbzd. in note, that the mercury. at
Quito flands at the height of twenty inches and one line:
how then is it poffible that it fhould ftand at eighteen inches
and one line at Guancavelica, which mutt be much lower, if
the barometer were not ill conftruéted ? No difference of tem-
perature between Quito and Guancavelica could caufe fuch
an enormous difference as two inches in the mercurial height.
The art and necefity of freeing barometers from air were not

generally

,

16 Dr. Kirwan on the primitive State of the Globe:

generally known * before Mr. De Luc’s immortal work on
the modifications of the atmofphere, which was not pub-
lithed till upwards of thirty years after Don Ulloa’s experi-
ments. The air, then, remaining in his barometer, which
he probably filled at Lima, in whofe territory Guancavelica
lies, under a preflure of 28 or between 27 and 28 (French)
inches, muft have confiderably expanded and depreffed the
column of mercury under it when brought up a mountain of,
perhaps, 7000 or 8000 feet high; and hence this mercurial
column remained fo low at Guancavelica as eighteen inches
and one line.

That in thefe circumftances the air contained in the baro-
meter might caufe a difference of three inches or more be-
tween the height at which mercury purged of air would
ffand, appears by the experiments of Caffini, Mem. Par.
1740, fur la Méridienne de Paris, p.172; for he found that
the mercury, freed from air by ebullition in the tube, ftood
four or five lines higher than in barometers filled without
that precaution. Nay, cardinal Luynes found the difference
betwixt fuch barometers to amount fometimes to fourteen
lines; Mém. Par. 1768, p. 490, in 8yo. How great muft
it therefore be in barometers tranfported to greater heights
than that at which they were filled?

Moreover, Don Ulloa exprefsly tells us that the mountain
on which thefe fhells were found was every where habitable,
Mim. Philofophiques, p. 34 and 35; which it could not be,
and would be exprefsly contradi€ted by Bouguer, if its height
were 13,000 Englifh feet over the furface of the fea, From
all which T conclude that the height of the mercurial column,
if the barometers had been properly conftruéted, would have
been about 22 French inches, = 23,44 Englith ; and, as the
temperature was remarkably cold, this would mdicate a height
of about 8200 feet above the level of the fea.

But, fecondly, let the height be what it may, it is certain
that thefe fhells were depofited there after the emerfion of
land from the primitive ocean, and confequently by a fub-
fequent deluge; for Don Ulloa exprefsly tells us, that in the,
fame rocks in which thefe fhells are found, petrified wood is
alfo found; Mém. Philofophiques, p.372. This wood muft
have grown on dry land, and mutt have been floated when

* J fay, not generally known, becaufe, though Mr. Du Fay had fhown
the advantage of expelling air from the mercury in the tube, in Mém. Par.
1723, and Caffini had followed that method in meafuring the heights of
Puy de Dome and Mont d’Or in 1740, yet it was not generally adopted
until! Mr. De Luc had proved its neceffity, and perfeéted the method of
performing it, in 1772. See De Luc, i. p. 58,

the

%

On the Colours obtained from the metallic Ovides. 17

the hells were depofited, fince both are found in the fame
rocks. It muft have been brought thither by a deluge, as
no wood can at prefent grow there, as Don Ulloa alfo attelts.
‘The thells are for the moft part bivalves, which geologifts
‘allow to form petrifaGtions of the moft modern date. 5

Lafily, La Peyroufe mentions that he difcovered marine
fhells. on mount Perdu, the higheft of the Pyrenees, at the
height of nearly 10,000 feet. How he afcertained the height
is not mentioned: but that thefe fhells were depofited by the
deluge is certain; for at the fame height he found alfo the
‘bones of land animals petrified. Journal des Mines, xxxvil.

P-.59, 60, and 64.

Ill: An Effay on the Colours obtained from the metallic
Oxides, and fixed by Fufion on different vitreous Bodies.
By ALEXANDER BrRocGniart, Direéor of the National

Manufactory of Porcelain at Sevres, Engineer of Mines, Sc.
[Concluded from p. 348 of our laft volume.]

A SMALL book, entitled L’ Origine de 1’ Art de la Pein-
ture fur Verre, publifhed at Paris in 1693, and the Trazté
del’ Art dela Verrerie*, by Neri and Kunckel, feem to be
the firft works that contain a pretty complete defcription of
the art of painting on glafs. Thofe fince publithed, even the
large work of Leviel, which forms part of the arts and ma-
nufactures of the academy, ‘and what is faid’in the Encyclo-
pidie Méthodigue, are merely compilations from the two
preceding works,

It is very remarkable, that if the proceffes defcribed in
thefe works were ftriétly followed, as we did in regard to
fome, it would never be poffible to form the colours for which
they pretend to give recipes. They only put the able artift
in the way, but he muft always make amendments or addi-
tions. This was the cafe with C. Miraud, who has the
eate of preparing the colours at the manufactory of Sevres,
He was obliged, rather from his own knowledge than the in-

‘formation contained in the above books, to make the colours

‘employed for painting on glafs.

The limits of a memoir will not allow me to enter into -

shiftorical details refpeéting the art of painting on glafs: a
full hiftory of it has been given in the work of Levicl above
‘mentioned. ‘Lhe matters and fluxes which enter into the
“© There is an Englith tranflation of this work entitled Neri’s Art of
Glof. ~ . : :

Vou, XIV. No. 53. B compofition

‘

t8 Ox the Colours obtained from the metallic Oxides,

comipofition of the colours employed on glafs are, in general,
the fame as thofe applied to porcelain. Neither of them differ
but in their proportions; but there are a great number of
enamel or porcelain colours which cannot be applied to glafs,
where they are deprived of the white ground which ferves to
give them relief. When feen by refraction, feveral of them
entirely change their tone, and affume a dirty tint, which can
be of no ufe: we fhall make them known when we come to
treat of colours in particular. Thofe which ean be em-
ployed on this body change fometimes in baking, and ac-
quire a great tranfparency. In general they are not beau-
tiful; but, when placed between the light and the eye, they
then feem to anfwer the only object that can be propofed in
painting on glafs.

The baking plates of painted glafs prefents more difficul-
ties than might be fuppofed. Care muft be taken not to dis-
figure the piece, or alter the colours: all the works we have
read recommend a bed of gypfum. This method has fome-
times fucceeded ; but the glafs, for the moft part, becomes
white and full of cracks. It appears that glafs too alkaline
(and alkalies are the mof common in white glafs) fuffers it-
felf to be attacked warm by the fulphuric acid of the fulphate
of lime. We were eafily able to bake pieces of glafs much
Jarger than thofe before painted, by placing them on very
ftraight plates of earth or of foft porcelain.

Of Colours in particular.

After colleGting the general phenomena exhibited by each
clafs of vitrifiable colours, confidered in regard to the body
on which they are applied, I muft make known the moft
interefting particalar phenomena exhibited by each prin-
cipal kind of colours employed on foft porcelain and glafs in
a porcelain furnace.

Of Reds, Purples, and Violets, made from Gold.

Carmine red is obtained by the purple precipitate of Caffius:
it is mixed with about fix parts of its lux; and this mixture
is employed directly, without being fufed. It is then of a
dirty violet, but by baking it acquires a beautiful red carmine
colour: it is, however, exceedingly delicate ; a little too much
heat and carbonaceous vapours eafily fpoil it. On this ac-
count it is more beautiful when baked with charcoal than
with wood.

This colour and the purple, which is very little different,
as well as all the fhades obtained from it, by mixing it with
other colours, really ehange on all porcelain and in every

hand.

and fixed by Fufion on different vitreous Bodies. 19

hand. But it is the only one that changes on hard porce-
Jain, Its place may be fupplied by a rofe colour from iron
which does not change; fo that by fuppreffing the carmine
made with gold, and fubftituting for it the rofe oxide of iron
here alluded to, you may exhibit a palette compofed of colours
none of which change ina remarkable manner. This rofe-
coloured oxide of iron has been long known; but it was not
employed on enamel, becaufe on that fubftance it changes
too much. As the painters on enamel, however, have be-
come the painters on porcelain, they have preferved their
antient method.

_ It might be believed that, by firft reducing to a vitreous
matter the colour called carmine already mixed with its flux,
it might be made to affume its laft tint. But the heat ne-
ceflary to fufe this yitreous mafs deftroys the red colour, as
I haye experienced. Befides, it is remarked that, to obtain
ip colour very beautiful, it muft be expofed to the fire as

ew times as poffible.

The carmine for foft porcelain is made with fulminating
gold flowly decompofed, and muriate of filver: no tin enters
into it; which proves that the combination of the oxide of
this metal with that of gold is not neceffary to the exiftence
of the purple colour.

Violet is made alfo with purple oxide of gold. A greater
quantity of lead in the flux is what gives it this colour, which
is almoft the fame crude or baked.

Thefe three colours totally difappear when expofed to a
great porcelain heat.

Carmine and purple have given us in glafs tints only of a
bi violet. The violet, on the other hand, produces on
pla sa very beautiful effet, but it is liable to turn blue. “I

ave not yet been abje to difcover the caufe of this fingular
change, which I faw for the firft time a few days ago.

Red, Rofe, and Brown Colours extra&ed from Iron.

Thefe colours are made from red oxide of iron prepared
with nitric acid, Thefe oxides are further calcined by keep-
ing them expofed to the action of heat. If heated too much,
they pals to brown,

Their fiux is compofed of borax, fand, and minium, ia
fmall quantity, ty

Thele oxides give rofe and red colours capable of fupplying
the place of the fame colours made with oxide of gold. When
properly employed on hard porcelain, they do not change at
all, I baye caufed rofes, to be painted with thefe colours,
and found no difference between the baked flower and that
| ae Ba not

40 On the Colours obtained from the metallic Ownides,

not baked, except what might be expected to refult from
the brilliancy given to colours by fufion..
~Thefe colours may be employed indifcriminately, either’
previoufly fufed or not fufed. i .
_ In a great heat they in part difappeat, or produce a dult
brick red ground, which ts not agreeable. poet
~The compofition of them is the fame, both for foft porce-'
Tain and, for glafs. ‘They do not change’on the latter; but.
on foft porcelain’ they difappear almott entirely on the firft
expofure to heat, and to make ‘any thing remain they muft
be employed very deep. fi pert
“This fingular effect muft be afcribed to the prefence of lead
im the cruft or glazing. I affured myfelf of this by a very.
fimple experiment. I placed this colour on window glafs, ~
and, having expofed it to a ftrong baking, it did not change,
' I covered feveral parts of it with mmium; and again éx-
pofing it to the fire, the colour was totally removed in, the
places where the red oxide of lead had been applied.

‘By pesforming this operation on a larger feale in clofe vef-
fels, a large quantity of oxygen gas was difengaged. —
Tt appears to me that this obfervation clearly proves the:
- ation of oxidated lead on glafs as a deftroyer of colour: it
is feen that it does not. act, as was believed, by burning the
combuttible bodies, which might tarnifh the glafs, but by
diffolving, ‘ difcolouring, or volailisina with it the oxide of
iron, which might alter its tranfparency. ”

: Yellows.

Yellows are colours which require a. great deal of care in
the fabrication on account of the lead which they contain,
and which, approaching fometimes to the metallic ftate, pro-
duces on. them black f{pots. | ra

The yellows for hard and foft porcelain are the fame: they
are compofed of the oxide of lead, white oxide of antimony,
and fand. :

Oxide of tin.is fometimes mixed with them ; and when it
is required to have them livelier, and nearer the colour du
Jouci, ted oxide of iron is added, the too great rednefs of
whichis diffipated in’ the previous fufion to which they are
expofed by the action. of the. lead contained in this yellow.
‘Thefe colours when once made never change: they difappear,
however, almoft entirely when expofed to a porcelain heat.
© Thefe, yellows cannot be applied to glafs:, they are ‘too
opake and dirty, That employed by the old painters on glafs
_ has, on the contrary, a beautiful tranfparency, is exceedingly
brilliant, and of a.colour which approaches near to that of
gold. The’ procefles which they gave clearly malic

Ver

and fixed by Fufion on different vitreous Bodlicso D> a

filver) formed part of their compofitions, but, when exactly
followed, nothing fatisfaétory was obtained. . C. Mirauds,
whom I have already had occafion to mention, has found
means to make as beautiful paintings on gials as the antients,
by emploving muriate of filver, oxide of zinc, white argil,
and yellow oxide of iron. ,Thefe colours are applied on
glafs merely pounded, and without a flux, The oxide of
iron brings the yellow to, that, colour which it ought to have
after baking, and contributes with the argil and ‘oxide of zinc
to decompofe the muriate of, filver without deoxidating the
filver. _ Atier the baking, there remains a duft which has not
penetrated into the glafs,and:which is eafily removed. ¥

This yellow, when employed thicker, gives darker fhades,
and produces a ruflet..

Blues.

It is well known that thefe are obtained from the, oxide of
cobalt. All chemifts are acquainted with the preparation of
them. Thofe of Sevres, which are jultly efteemed for their
beauty, are indebted for it only to the care employed in ma-
nufaéturing them, and to the quality of the porcelain, which
appeats more proper for receiving them in proportion to the
degree of heat it can bear. itt

I remarked refpecting the oxide of cobalt'a fa&t which
is perhaps not known to chemitts: it is volatile ina violent
heat: it is to this property we muft aferibe the blueifh tint
always affumed by white in the neighbourhood of the blue.
I have placed exprefsly on purpofe, in the fame cafe, a white
piece clofe to a blue one, and found that the fide of the whit
piece next the blue became evidently blueifh.

The blue of hard porcelain, deftined for what is. called the
ground for a great heat (/es fonds aw grand feu), is tufed
with feld-fpar; that of foft porcelain has for its flux filex,
potath, and lead: it is not volatilized like the preceding, but
the heat it experiences is very inferior to that of hard porce-
Jain.

Thefe colours, when previoufly fufed, do not change at all
in the application:

Blues on glafs exhibit the fame phenomena as thofe on
oft porcelain,

Greens.

The greens employed in painting are made with green oxide
of copper, or, fomietimes, with a mixture: of yellow or blue.
They muft be previoufly fufed with their flux, otherwife they
will become black; but after this firtt fufton they no longer

hange,
. 6 B 3 ¥ hey

22 On the Colours obtained from the metallic Owides,

They cannot ftand a ftrong heat, as it would make them
difappear entirely. Green grounds for a ftrong heat are com-
péfed with the oxides of cobalt and nickel, but a brownifh
gteen only is obtained.

Blueith greens called cele/fial blues, which were formerly
édlours very much in vogue, can be applied only upon foft
oe a on hard porcelain they conftantly become fealy,

ecaufe potafh enters into their compofition. c

Thefe greens cannot be applied on glafs: they give a dirty
colour. To obtain a green on glafs, it is neceflary to put
yellow on oné fide, and blue, more or lefs pale, on the other.
This colour may be made alfo by a mixture of blue with
yellow oxide of iron. I hope to obtain from oxide of chrome
a direct green colour. The trials I have made give me reafon
to hope for fuccefs. Pure chromate of lead, which I applied
to porcelain in a firong heat, gave me a pretty beautiful
green of great intenfity and very fixed.

Bifires and Ruffets.

Thefe ate obtained by mixtures in different proportions of
manganefe, brown oxide of copper, and oxide of iron from
ombre earth. They are alfo previoufly fufed with their flux,
fo that they do not change in any manner on foft porcelain,
as lead has not the fame action on oxide of manganefe as on
that of iron, as J aflured myfelf by an experiment fimilar te
that already mentioned.

This colour fades very fpeedily on glafs.

Ruffet grounds in a great heat, known under the name of
tortoife-fhell grounds, are made in the fame manner. ‘Their
flux 1s feld-fpar: no titanium enters into their compofition,
‘though faid fo in all printed works. Titanium was not known
at the manufactory of Sevres when I arrived there. I treated
this fingular metal im various ways, and never obtained but
grounds of a pale dirty yellow, and very variable in its tone,

Blacks.

Blacks are the colours moft difficult to be obtained very
beautiful, No metallic oxide gives alone a beautiful black.
Manganefe is that which approaches neareft to it. Iron gives
an opake, dull, cloudy black, which changes very eafily ta
red; the colour-makers, therefore, to obtain a black which
they could not ‘hope for from the beft theorift, have united
feveral metallic oxides which feparately do not give black,
and have obtained a very beautiful colour, which, however,

is liable to become fealy and dull,
Thefe

and fixed by Fufion on different vitreous Bodies. 23

Thefe oxides are thofe of manganefe, the brown oxides of
copper, and a little of the oxide of cobalt. The gray is ob-
tained by fuppreffing the copper, and increafing the dofe of
the flux. ’

The manufactory of Sevres is the only one which has hi-
therto produced beautiful blacks in a ftrong heat. This is
owing rather to the quality of its pafte than to any peculiar
proceiles, fince it does not conceal them. It is by darkening
the blue by the oxides of manganefe and iron that they are
able in that manufactory to obtain very brilliant blacks.

Having here made known the principles of the fabrication
of each principal colour, it may be readily conceived that
by mixing thefe colours together all the fhades poffible may
be obtained. It is evident alfo that care in the preparation,
choice in the raw materials, and a juft proportion of dofes,
muft produce in the refults differences very fenfible to an eye
accuftomed to painting. A mere knowledge of the compofi-
a of the colours does not give the talent of executing them
well.

In recapitulating the faéts above mentioned, to prefent
them under another general point of view, it is feen:

ift, That among colours generally employed on hard
porcelain one only is fufceptible of changing, viz. carmine,
and the tints into which it enters: that its place may be
lapped by the reds of iron, and that no colour then changes.

have prefented to the Inftitute a head not baked, exe-
cuted according to this method; and the painting of two
roles, that of the one baked, and that of the other not baked.
It has been {ven that there was no difference between them.
2d, That among the colours for foft porcelain and enamel,
feveral change in a confiderable degree. Thefe are princi-
ally the reds of gold and iron, the yellows, the greens, the
eit. They have not been replaced by others, becaufe
this kind of painting has been almott abandoned.

3d, That feveral of the colours on glafs change alfo by
acquiring complete tranfparency, Thefe in particular are
the yellows and greens.

4th, That it is neither by calcining the colours in a higher
degree, nor previoufly fufing them, as fuppofed by fome,
that they are prevented from changing, fince thefe means
really alter the changing colours, and produce no eflect on
the reft. The change which feveral colours experience on
foft porcelain and on glafs does not then depend on the na-
ture of their compofition, but-rather on that of the body on
which they are applied.

Confe-

24 Tubes rendered harmonious by Hydrogen Gas...

Confequently, by fupprefling from the colours of hard
porcelain the carmine of gold, which is not indifpenfably, ~
neceflary, we fhall have a feries of colours which do not
change, and which will be abfolutely fimilar'to thofe pre-
fented to the Inftitute in the year 6. es /

IV. Memoir on Tubes rendered harmonious by Hydrogen Gas.
Read before the Society of Phyfics and Natural Hiftory of
Geneva, by G. DELARIVE, Ex-Prefident of the Royal
Society of Edinburgh, and Member of the Medical’ Col-

leges of London and Geneva*.

lw a former fitting, our learned colleague profeffor Pictet
communicated to the fociety a feries of refearches on tubes
rendered harmonious by means of hydrogen gas, and ex-
plained the different mufical phenomena to which thefe
tubes give birth. He pointed out the influénce of the length
of the tube; of its breadth, and of the place where the gas
is‘burnt; and explained the nature of the founds produced.
In regard to the caufe of the found, he offered only conjec-
tures: as his labour was not dire€ted-to that objeét, it is
under this point of view that I have refumed it.

Profeffor Brugnatelli, in my opinion, is the firft perfon
who publifhed the experiment; which I fhall endeavonr to
explain. It had been invented by a German: I fhall here
give a view of the principal circumftances attending it.

If a current of inflamed hydrogen gas be introduced into a —
tube the fubftance of which is elaftic and fonorous, fuch as
glafs, metal, dry wood, &c., this tube, after the interval of
fome feconds, will emit a harmonic found : if it be open at
both extremities, the found will be ftrong and full. The ex-
periment may, however, fucceed with a tube clofed herme-
tically at one end, provided its diamcter be fo large as to ad-
mit of acirculation of the atmofpheric air in fufficient quantity
to maintain the combuftion of the gas. The conditions ef-
fentially neceflary for this purpofe are: 1ft, That the fub-
ftance of the tube be elaftic, proper for producing an echo 3
that is to fay, for refleing the undulations which proceed
from the fonorous point: a tube of paper or pafteboafd will
emit no found. 2d, The flame muft be produced by a cur-
rent of hydrogen gas. An inflamed jet of the vapour of f{pirit
of wine or ether, a lighted taper, &c. are incapable of making
the tube emit any found.

* From the Journal de Piyfique, Fruétidor, an, 10,

Let

Tubes rendered harmonious by Hydrogen Gas. 25

Let us now examine what takes place in this experiment.
There mult be a certain point, which may be called the /o-
morous points it in at this point that the vibrations which
communicate to the air an undulatory motion are produced,
This potat is the place of combufion; for by changing the
polition of that place the founds may be varied, as M, Pictet
proved by a feries of experiments. , This gentleman. obferved
alfo in that point, by means of the fmoke with which he
filied the tube, a continual fucceffion of vibrations. Thefe_vi-
brations give birth to undulations, which are propagated with
a known and determined velocity, and, ‘iriking the fides of
the tube, are reflected with the fame velocity as that with
which they reached them, When the diftance of the fides of
the tube is fuch that the refleGtions backwards and forwards
are ifochronous with the vibrations natural to the fonorous
caufe, the found increafes in intenfity, and becomes mufi-
cally appreciable. It appears alfo that the reflected undula-
tions re-a¢t on the primitive vibrations produced in the place
of combuftion, and render them harmonically regular with
them; jor a certain fpace of time is almoft always necefla
before the inftrument has acquired a regular and fall found:
the tone of the tube will be bigher or lower according to the
ereater or lefs number of undulations which take place ina
given time,

There is another effential fact to be obferved in the expe-
riment which we here examine: the temperature of the co-
Jumn of air is not the fame throughout its whole length. At
the fonorous point, that is to fay, the place of combufiion,
the temperature is-exceedingly high; it is fuch, that the ex-
tremity of the aperture of the glafs through which the hy-
drogen gas iffues is conftantly in a ftate of incandefcence:
if an inflamed jet of the vapour of {pirit of wine or ether be
fubftituted for a current of hydrogen gas, the heat ts vifibly
weaker. According to fome experiments it appears probable
alfo that the temperature of the chamber where the experi-
ment is made, and the purity of the air in the chamber, may
have fome influence on the refult,

The objeé& of my refearches was to difcover the caufe of
thefe phenomena, and how, and by what means, thefe fouo-
rous vibrations are produced. During the combuition of hy-
drogen gas, it is well known. that there isa prodifétion of
water, and this water appears under the form of vapours.
The place of the combuttion being at a high tenyperature,
thefle repeat mutt acquire a large volume ; but, coming m-
micdiately into contaét. with air lefs heated, their volume mult
be rapidly diniinifhed, A vacuum therefore mutt be formed,
’ 5 . Anto

6 Tubes rendered harmonious by Hydrogen Gas.

into which the air rufhes to be repelled by the new vapours,
that contra& in their turn. Is it from this alternate motion,
produced by the great expanfion and fubfequent contraction
of the vapours, that the fonorous vibrations refult * ?

Such were the conje&tures which might be formed on the
probable caufe of this phenomenon, when I accidentally
met with a faét which appeared to me to give them fome
weight.

I had a thermometer tube about a line in diameter, at the
extremity of which a fmall bulb was blown. In this bulb
was a drop of water, which I withed to expel: for this pur-
pofe I expofed the bulb feveral times to the flame of a fpirit-
of-wine amp. I was agreeably furprifed to hear the tube
emit a harmonious found.

To repeat this experiment with fuccefs, the tube employed
muft be from r to 2 or 3 lines in diameter: its length may
be about from 3 to 4 or 5 inches: it muft have blown at one
of its extremities a bulb the diameter of which is about triple
that of the tube. It is not neceffary that it fhould be regular,
It even appears that, if it were a little flatted, the found
emitted would be higher. Into this bulb introduce a little
quantity of water or mercury, and then expofe it to a ftrong
heat: that of a common fpirit-of-wine lamp will, in general,
be fufficient; but the flame mutft be large and ftrong when
the operation is performed with a large tube. After the bulb
has been expofed for fome moments to the heat, it will emit
afound., ‘Tubes of a large diameter produce a found lower

* Tt appears to me probable that the found produced by the air which
rufhes into the vacuum is more intenfe than that which refults from an
expanfive force. The dreadful noife occafioned by the detonation of bub-
bles of hydrogen gas and oxygen is well known, and yet the lighteft obs
jects which furround the veffel ave'not even agitated by it; whence we may
conclude that this phenomenon is produced by the fudden vacuum refult-
ing from the deftruction of the gas. The detonation of an inflammable
yas piftol is much ftronger than that of the air-gun, though the effect is
Jefs confiderabie; probably becaufe in the piftol a vacuum fucceeds the
firft expanfive force. Every body is acquainted with that children’s play-
thing called the humming top. Jt confifts of a hollow fphere with an
aperture at the circuniference, which being made to turn rapidly on its
axis produces a very ftrong humming noile. What is the caute of this
noife? The fame, in my opinion, as that above mentioned: the centri-
fugal force expels the air from the fphere through its aperture; a kind of
vacuum is formed in it, the exterior air continually tends to enter it, and
is immediately repelled, and ‘hence’a feries of {onorous ofcillations, — The
AUTHOR.

The effect here fpoken of feems rather to arife from the velocity with
which the edge or lip of the orifice meets the air ; for the fame found may
be produced by direéting a ftream of air againft the lip when the top is
ftationary.—EpiT.

7 than

7

-

Tubes rendered harmonious by Hydrogen Gas. Dj

‘than others. The fize of the bulb appears to me alfo to con-
tribute towards the fame effet. The found will be perma-
nent for fome moments; it will then gradually decreafe, and
at length will entirely ceafe. By fuffering the apparatus to
cool, and taking care to make the liquid condenfed along
the fides of the tube to defcend into the bulb, the experiment
may be repeated as often as may be thought proper.

Such is the experiment by means of which, in my opi-
nion, the phenomenon of the harmonious tubes may be ex-
plained in a fatisfactory manner, Let us now examine what
takes place in tubes with a bulb, and what are the effential
conditions neceffary to make them emit a found, and let us
endeavour to difeover the caufe of this found. We fhall then
compare them with the tubes employed with hydrogen gas,
and fhall examine in what thefe two inftruments refemble
each other in the effects they produce, the differences they
exhibit under the fame relations, and the caufes of thefe dif-
ferences.

The effential conditions neceflary to make tubes with a
bulb refound are: i1{t, That the veffel has a bulb: I was
never able to excite fonorous vibrations in a tube fimply
clofed at one of its extremities. 2d, This bulb muft con-
tain an evaporable liquid: water fucceeds very well; but it is
attended with the diladvantage of forming in the tube, when
it paffes from the ftate of vapour to the liquid flate, a fmall
drop which often obftruéts it entirely, and, fometimes, falling
on the heated part of the glafs, occafions a rupture. Mercury
is not attended with the fame defect : Iwas never able to pro-
duce founds with ether, fpirit of wine, or concentrated ful-
phuric acid. The quantity of liquid contained in the bulb
Is not a matter of indifference; it muft be as fmall as poffi-
ble: if there be too much, the tube becomes filled with va-
pours, which completely expel the air from it, and, heating it
every where in an uniform manner, it no longer emits any
found. The third effential condition is the application of a
ftrong heat to the bulb while the reft of the tube remains
cold; for, if there be not a very ftriking difference of tempe-
rature between the bulb and the tube, there will be no fonorous
effeét. In the laft place, the prefence of atmofpheric air
is indifpenfably neceffary : if it be entirely expelled, no effeét
can be produced, Jn all the periods of the experiment it
will be found that the vapour fills only a certain portion of
the inftrument, and that it always contains air. I made
feveral trials to determine exactly the {pace occupied by the
vapour at the moment when the found is heard; and I have
found that, in {niall tubes at leaft, this {pace 1s aia «5

than

28 Tubes rendered Dhaniveepsteais by Hydrogen Gas.

than the volume of the bulb. | To determine it, I.{hut with,
my finger the orifice of the tube: at the moment when it
began to found, I immerfed the orifice in mercury, removed.
my finger, and left the apparatus to cool, The vapour be-
came condenfed ; and I could judge, by the quantity of mer-
_eury which the preflure of the atmofpheric air made to afcend
in the tube, the {pace which the vapour had. occupied.
_ Such are the four conditions effentially neceflary for ob-
taining founds: a bulb at the extremity of the tube; the
pints of a very fmall quantity of water or mercury in the
ulb; the application of a ftrong heat to the bulb while the.
reft of the tube remains cold; and, in the laft. place, the
fimultaneous prefence in the apparatus of vapour and atmo-
fpheric air. It,is not neceflary to add, that the orifice of the
tube muft always be open. | Let us now examine what may
be the caufe of the found. I wifhed firft to afcertain whe-
ther any chemical decompofition of the liquid employed took
place. For this purpofe I took a tube st fuch a length that
the liquid might be entirely condenfed in it: - I weighed it
carefully before I’made the experiment: I then made it emit
founds, and found, after producing this effect feveral times,
that its weight had neither increaled nor decreafed ; whence
I concluded that caloric produces no chemical effeét on the
liquid, and that the latter merely undergoes fucceflive eva-
poration and condenfation. Is it to this evaporation, then,
of the liquid, and its condenfation, that the founds ought to
be afcribed? At firft I believed that this queftion might be
anfwered in the affirmative ; but the following confiderations
made me change my opinion: I firft obferved that there
might be a fucceffive evaporation and condenfation, without
the tube emitting any found, on applying to the bulb a fufi-
cient heat, but Jefs intenfe than that neceflary for making
the tube found. Secondly, in making the experiment with —
a drop of water, I conftantly found that the moment when the
apparatus began to enter into action was that when the whole
of the water was evaporated, and, confequently, when the
heat a€ted on the vapour: if a fingle atom of liquid remained
in the bulb, the tube’ was mute. From. this fact I conclude
that the found is produced by the action of the caloric on
the vapour, and the reaction of the latter on the atmofpheric
air. The following is the manner in which I conceive that
this phenomenon takes place: The vapour contained in the:
bulb receives, by an addition of caloric conveyed to it from
every part in a large quantity, an increafe of volume and of
_ elatticity ; it proceeds with force from the bulb to the tube,
and expels the air contained in it; but this air and the fides

of

Tubes rendered harmonious by Hydrogen Gas. ey

of the tube take from it, at the moment of contaét, a portion
of the caloric, its volume décreafes, at the fame inftant a
vacuum ‘takes place, and the air refumes its primitive {pace.
A ‘new addition of caloric reftores ‘to the vapour its whole
elafticity, a part of which it foon. lofes in the fame manner.
This is a confequence of the ofcillations of that nature which
give to'the air an undulatoty movement. The, undulations
tefleGted by the fides of the tube become fonorous and ap-
preciable when they are ifochronous with the ofcillations
produced by the caufe [ have indicated. From fome tubes
it is mpoffible to produce any found: in thefe I am of opi-
nion that the'reflected undulations cannot harmonize with
the primitive ofcillations, and that the one deftroy the other.
In tubes with bulbs, the found, after a certain time, becomes
weaker, and at length ceafes.. This may be explamed ‘by the
propagation of heat along the fides. . When the bulb is very
warm, and the tube cold, the vapour which rifes from the
bulb fuddenly lofes a part of its volume, ‘and the ofcillations
thus produced are {trong ‘and frequent ; but when the tube
has acquired a certain decree of heat, the vapour gradually
dalbben fed in volume by pafline froma very hot temperature
into a place lels warm indeed, byt which, however, has 2
fufficient degree of heat 'to make’ the ofcillations,. which be-
come weaker and fainter,’ ‘to ceafe at length entirely. That
fuch is the caufe of the ceflation of the found may be proved
by applying a ftrong heat to the part of the tube “already
heated, maintaining at the fame time the fame degree of
heat under the bulb: by thefe means the limits of the tem-
peratures are again very abrupt, and the found will be repro.
duced in its full force.” Tt may be readily conceived’ that ‘the
fubftance of the tube muft he fonie matter a noh-conductor
of heat: glafs, therefore, ‘is preferable. = ® /

~ Let us now compare the apparatus of a tube having a bulb
with thofe ‘tubes in which hydrogen gas is empfoyed. In
the latter we have every thing necéffary for the produétion of
found, a vapour very hot, and confeqnently highly elaftic ;
for, as already obferved, the place of the combuftion is at fo
high a temperature that the beak of the glafs’is’ conftantly
vel: This hot and elaftic vapour, at the moment of its pro-
du&ion, is in contaét with the cold air, which enters the
tube at the bottom ‘and iffues’ at'the top; its volume mutt
then decreafe a moment after it has touched that cold air:
new hot vapours fiieceed ‘the former, and contraé im their
turn. This qlternate’exparifion and contraction’ gives birth
to the undulatory moyement of the air, and fonorous undula-

i5 ont j m3 49h)

tions, “li
mie We

86 Tubes rendered-harmorious by Hydrogen Gass

We have already feen that an inflamed jet of fpirit of wine
or of ether cannot make the tube found. This 1s a new
proof of what I have advanced, that to produce found there
muft be a great difference between the temperature of the
vapour and that of the furrounding air. In this cafe there
is a fucceffiye formation and condenfation of vapour, ‘for the
water {treams along the fides of the tube; but the place of
combuftion has a much inferior degree of heat to what it has
when hydrogen gas is burnt, and confequently the vapour
produced has lefs heat as well as lefs elafticity.. This cafe 1s
analogous to that already mentioned, when we faid that a fuc-
ceffive evaporation and condenfation of the liquid might be
proeneet in a tube having a bulb, without any fonorous ef-

eéts, by expofing the bulb to a certain degree of heat, but
lefs intenfe than that neceflary for making the tube emit a,
found. We fhould not be furprifed if lefs heat were produced
by the combuftion of fpirit of wine, or ether, than by that of
hydrogen gas, when it is confidered that in the latter cafe
all the caloric contained in this gas, and in the oxygen of the
atmofpheric air confumed, becomes fenfible heat, and unites
itfelf entirely with the vapour produced. On the other hand,
in the combuftion of an inflammable fubftance, fuch as fpirit
of wine, we have only the caloric of the oxygen confumed,
rendered fenfible, and which is in a great meafure abforbed
by the formation of carbonic acid gas, fo that it is only the
excefs which joins the vapour. It is therefore not aftonifhing
that we have not heat fufficient to give to this vapour all the
elafticity neceflary for the production of found: the prefence
of the carbonic acid gas refulting from the combuftion may
alfo be an obftacle to the fonorous vibrations.

In tubes employed with hydrogen gas, the found is much
ftronger than ingthofe having bulbs: befides, in the former
it is permanent, in the latter it continues only a few mo-
zacnts, The. reafon of this is asfollows: In the apparatus
«ib hydrogen gas the tube is open at both extremities, con-
feguently there is formed a current of frefh air, which enters
at the bottom and : fues at the top; this currentiof air {weep-
ing along with the hot and elaflic vapours receives their im-
pulfe, and, by taking from them a portion of calorie, dimi-
nifhes their volume: we find here, therefore, the moft effen-
tial condition for the production of an intenfe and permanent
found, viz. a great difterence between the temperature of the
ir and that of the vapour; and this difference always remains
the faise by the continual renovation of the air; but this
does not take place in tubes with bulbs, and therefore,the
found they emit is weaker and of fhorter duration. ‘
rom

On Painting, ot

From this principle, that the great difference between the
temperature of the vapour and air is neceffary for the pro-
duction of found, it may be eafily conceived that every thing
which tends to augment the heat of the current of air, and
to diminifh that produced by the combuftion of the gas, will
tend alfo to weaken or even to annihilate the found of the
tube: but thefe two circumftances are united in a warm
chamber filled with people: the current of air, inftead of
being cool, is hot, and the quantity of oxygen being there
Fefs, the heat produced will be of lefs ftrength. It needs
therefore excite no a(tonifhment, that in fuch chambers the
experiment does not always fucceed.

Brugnatelli produced founds in tubes merely by the com-
buftion of phofphorus. Some philofophers, conceiving that
the fonorous effects were owing in a peculiar manner to the
hydrogen gas, have been induced to infer the prefence of that
fubftance in phofphorus. From what has been faid, is it not
More fimple to explain this phenomenon by the production
of the phofphorous acid under the form of vapours, which
receive a great degree of elafticity from the caloric difengaged
during. the combuftion, and the volume of which is foon di-
minifhed by the contact of the cold air? We find there the
alternate expanfion and contraction neceflary for communi-
cating to the air the undalatory motion proper for producing
founds.

Such are the few obfervations I have had an opportunity
of making on harmonious tubes; I hope they will prove in
fome meafure intere{ting to thofe particularly engaged with
this branch af philofophy, and that they will contribute to-’
wards making them pay attention to this curious fact hitherto

neglected.

lee

V. On Painting. By Mr. E. Daves, Painter,
_ Essay V.

On Invention,

Thett, béld Invention, all thy powers diffufe,
Of all, thy fifters thou the mobleft mufe ;
Thee ev'ry art, thee ev'ry grace infpires,
Thee Phebus fills with all his brighteft fires.
Mason’s Fresnoy.

V \ E fhould never forget that the value of every art arifes
from the degree of mental capacity requifite to its production,
and the degree of inftruction or pleafure refulting therefrom.

Hence

3% On Painting.

Hence invention is jufily ranked as the firt and moft noble
part of the art; by it we diftinguifh the philofopher from the
mere painter, for he whofe powers are confined to imitation
deferves no better name. wn

Invention not only relates to the way in which the artift
tells the itory; but, in a higher fenfe, requires ‘the aid of
fuch probable incidents as mav contribute to its further ilaf-
tration. © Raphael, in his Paul at Lyfira, has finely con-
trived to fhow the miracle wrought, by making one of the
fpetators, -full of wonder and aftonifhment, lifting ‘up the
drapery to examine the limbs that have acquired their proper
fhape. N. Pouflin, to convey an idea of the fize of Poly+
phemus, has placed him on the diftant mountains, and, by
mterpofing a creat medium of air, has feparated him from
the figures of the {ame fize on the fore-ground, and thereby

roduced a gigantic effect that beggars all defeription. Barry,
m his picture of Elyfiam, has reprefented fpiritual beings
conduéting the earth, thereby indicating that the world is
governed by a fupreme intelligence *.

The laws that govern hiftorical painting are not confined
to it, but extend to every other fpecies of compofitton : hence
it becomes the moft noble part of the art, and from which
all the others are but as fo many branches. It not only re-
quires a thorough knowledge. of the human figure, but its
attire, with landfcape, architecture, &c.; fo that we may
jeftly term it the only univerfal part of the art.

Some men, who term themfelves artifts, move in an orbit
fo confined that their motions are fearcely difcernible without
the aid of fome ftrong magnifier. Unfortunately for the arts,
the trifler meets with the moft fuccefs; perhaps the higher
parts of the art are not fo immediately within the reach of
the capacity of the common obferver: like jewels, their in-
trinfic value is known but to few. Sir Jofhua juftly ob-
ferves, ‘¢ that the loweft ftyle will be the moft popular, as it
falls within the compafs of ignorance itfelf; and the vulgar
will always be pleafed with what is natural, in the confined
and mifunderftood fenfe of the word.” Wifdom is rather
-an unprofitable commodity ; for we too often find in life the

* The above is one of a feries of piftures preferved in the great room
of the Society of Arts in the Adelphi. In thofe pi€tures the artift may
be faid to have invented his fubjeéts alrogether, and has fo conneéted them
as to illuftraté that great moral truth, ‘¢ that the attainment of happinefs,
individual as well as public. depends on the cultivation of the human fa-
‘cultiés,” © They exhibit a fine fy fterm of ethics, at rhe fame time that they
exprefs, ama moi determined ‘and matterly way, the beauty aad advan-
tages of legiflation.- eyeoh * "y
sonaki ‘ moft

On Painting. 33

moft: ignorant the moft fuccefsful, and the moft fuccefsful
the moft honoured. .

The great artifts of former times did not only practife
hiftory, but portrait, nay even land{cape, and often excelled
in architecture: then it was that one good work was enough
to infure a man fuccefs and fortune, while now twenty hafty
ones will fearcely furnith him bread. Little and poor fpirits
haye formerly made them feparate ftudies, and their inability
difgualified them from teaching on a more liberal and exten-
five fcale, and now the praétice of many is infignificant and
contemptible.

Man loves himfelf, and of courfe is interefted in whatever
relates thereto: hence the great end of painting fhould be,
recording actions of great perfonal patience, fufferance, or
heroifm; but, above all, embodying fome important moral
truth for the edification of mankind.

Some lofty theme let judgment firft fupply,
Supremely fraught with grace and majefty ;

PF For fancy copious, free to ev’ry charm
Thar lines can cireum{cribe, or colours warm +
Still happier if that artful theme difpenfe
A poignant moral and inftruétive fenfe.

Mason’s FRESNOY.*

That part of painting termed the ornamental may pleafe
and delight; but he who in his works combines fublimity with
fentiment, may be juftly faid to have reached one of the
higheft points of human felicity, and does an honour to the
ignorant by raifing them from their own native infignificance
to rank with the higheft order of earthly beings:

The dulleft genius cannot fail

To find the moral of my tale:

That the diftinguifh’d part of men,

With compats, pencil, {word, or pen,

Should in life’s vifir leave their name,

In characters which may proclaim,

That they with ardour ftrove to raife

At once their arts and country’s praife. PRIOR.

In the choice of our fubject we fhould prefer thofe beft
known, and, if poffible, fuch a one as may carry with it a
9 porate! intereft. As a poet, Milton was particularly happy in
is Paradife Loft; it is not the deftruétion of a city, or the
conduél of a colony, but the fate,of worlds, which involved
the happinefs of mankind at large.. The Greek and Rotman
hiftory with their fables, alfo the hiftory of our own nation,
_and the works*of our beft poets, furnith infinite matter for
AMtudy, as well as thofe grand. and, fublime fubjects that occur
in the Old and New Teftament. /
Vout. XIV. No. 53. C Buy

— a5 7

34 On Painting.

But in our choice from the above, of any other work, wé
are not bound, like cattle, to follow a leader; the fubjects
unhandled are endlefs; thofe in the Bible abound from the
moft fimple paftoral to fuch as are in the higheft degree fub-
lime. Befides, by exerting a proper degtee of independence
we fhal] not only be left free to aét, but thereby fland the
greater chance to give our works the charaéter of originality.
What could be more mortifying than to have it faid that the
beft part of our picture was pitifully ftoien from another?
This would render us like the poor animal when firipped of his
borrowed clothes, in which he looked fo formidable, when be-
hold he proveda mere afs! Such a conduét cannot be juftified
by any example found in a great mafier, whatever proofs he
had given of his powers of invention, and it would be equally
unpardonable in an artift of lefs celebrity. Nothing can be
fo contemptible as that poornefs of fpirit that goes limpmg
after another, crawling over objects like a flug, and leaving
nothing but flime behind : he never can be great that does not
greatly dare. The mind, acting from its own impulfe, will
energize with more vigour than it poffibly could by feeing
objects through the medium of another’s feelings. He who
Fmitates the manner of another debafes himfelf, by giving
his company to the fervant when the mifirefs is ready to en-
tertain him. :

Prints and drawings are ufeful to pleafe the eye or enrich
our thoughts, or, by having them before us, to keep up the
fervour of the mind while employed on fimilar works of our
own: then it is we may catch a grace from a figure, a grand
or beautiful caft of drapery, or a thought that may give energy
or brilliancy to our own, and that without copying. Collec-
tions of good prints are highly valuable to the artift; they
add a noblenefs to his conceptions, aud raife and warm his
imagination: fo do fine defcriptions in hiftory and poetry.
The prints after Raphael, M. Angelo, and the Caracc?, will
afford a fund of entertainment and inftru€tion ; and fine in-
ftances of forms in the back-grounds of Titian and Paul Vero-
nefe will be found with oceafional good eompofition. Rabens’s _
prints by Bolfwert will be highly worthy attention, as welk
as thofe after the moft celebrated French and Britith artifts.

We fhould be careful not to fuffer our purfuits to be inter-
rupted by vulgar opinions or prejudices, but purfue our ftudies
full of the conviction, ‘ that patience and perfeverance wilf
lead to perfection.” Nothing can be more abfurd than to
imagine one perfon too lively for fuch a ftudy, another too
grave, or a third too fober or honeft for a'genius: the faét is,
if we fuffer the opinions of others to affect our choice of over-

power

On‘ Painting. 56
power our refolves; wer refienourfelves:up to the-moft igno=
minious)flavery,' by giving ‘up the’ right of regulating out
own lives... When we: have arrived at this partoof the art,
we muft place fome confidence in our own {kill, otherwife
we dhall) be Jiable:td: perpetual! embarraffment from the va-
lous iopinidns of-others ¥ we fhould reft fatisfied if our works
do not violate any principle in nature or-rule/of art. He
whois doubtful of) his: own \abilities will derive litle advan-
tage from the remarks of others, and the refult of his inquiry
will produce a mafs Of crudeand independent hints, that can+
mot poflibly be reconciled, or collected/into one point. A
proper confidence is neceflary; he cannot: hope to fucceed,
who, before he begins; doubts-if ‘his abilities be equal to the
undertaking. j Sy OTH’ 9 | : 40

As it is the eteat end of art-to ftrike the imagination, when
iwevhave «made ‘choice of /a fabje&!that is lofty, grand, or
‘bedutiful, we muft bercarefulthat: ithdoes not fuffer in our
hands by the intrddaction of poor or mean_ thoughts, ugly,
Anfighificant, ‘or: commonplace: objects. Baflan, whatever
fabjett he chofe,:reprefented: it»by the peafants of his own
ycountry; which deprived it of every merit but fuch as de-
‘pended on-colour and effect: “How oppofite the condué& of
*Raphaelin the Cartoons! who; knowing bow much was ex-
pected from thofe:who praétifed the great ftyle, bas infufed
all thenoblenefs he was matter of into his apofiles, notwith-
ftanding hiflory furnifhes no authority for fo doing. As.we
cannot make our hero talk greatly, we muft make him appear
capable of great ‘a¢tions;) by adding all the externals of dig-
- nity andograndeur correfpondent to high fentiment and great
a¢tion 3: power which all men with, but few attain.

As. it isiniour power, fo it is our daty, to produce that
unity which nature does-not always do.) Thomfon has finely

. heightened the death of Amelia by the thunder-ftorm. A
murder perpetrated ina gloomy day, or at night, will affect
our feelings more ftrongly than in a broad flaring light.

Events become more compact, and of courfe more inte-
refting, by making the animate {cenes of nature more dread-
ful or lovely, or by adding a more fublime caft to the human

“countenance,
“Though many things in! nature and art.exceed expectation,
yet nothing fenfible has the power to: exceed or even equal
the capacity of thought: itis from this power of the mind
the artift derives” his advantage. Mountains may be ima-
~ gined Joftier or more pi¢turefque; lakes more extenfive and
clear, rivers more rapid or! flow, rocks. more vaft and wild,
: C2 caverns

35 On Paiiiting.
eaverns more gloomy, ruins more majeftic; and: the whole
face of nature drefled in fun or fhade as beft fuits our purs
pofe, whilewe may render the human figure more beautiful
or grand. . nant ow
-. The painter of hiftory, like the:hiftorian, reprefents the
event, not the man, which is the province of the: portrait=
painter andbiographer. : trier vets tf iol
-© The Datch ‘have ‘treated hiftory undet: circumftances' fo
purely local, that Chrift has appeared)in the:ftorm in.a’ com
mon fifhing-boat: with the tri-coloured flag flying; and Da-
Hila cutting a lock from a huge black peruke of the endof
fhe 17th century. reRSIOn et OS: FOE
Two advantages refult ‘from going to remote‘ hiftory. for
our fubjects: one is, it becomes more venerable; ‘another as,
thatthe inaccuracies! of co/lume are notrfo'eafily perceived.
The two divifions of hiftory generally rank under the grand
‘Atyle, and what sir Jofhua terms! the ornamental, but which
from its delighung in variety 1s better deferibed by the»word
pidiure/que, which 3s oftener applied,:and not of fo debafing
a nature. The picturefque is founded.on.an union of the
regular and irregular, the grand! or fimple, or the ‘regular
only: for inftance, the arch of a bridge which is wniformas
fimple and grand, but being broken: it becomes irregular/or
picturefque: decorations of ivy have a fimilar effeét.’ ‘A head
and body feen in front, with the hair flowing uniformly on
each. fide, as we fometimes fee in the portraits of Georgione
and Titian, is grand: incline the head, and vary the hair on
~one fide, it’ changes its charaéter to the picturefque. — Similar
eroups, nay, even fingle figures, perfectly alike, often yeha-
racterize the higheft fimplicity of compofition, asain fome of
Raphael’s pictures, and of which there is: afine inftance by
. Titian’ in the church of the Friarsof St. Franeis at Venice ;
-an etching of which, by Le Febre, ‘is in every one’s! hand.
Pouflin fhowed it in his landfcapes, in his buildings, and
in the ftraight and parallel ftems and-uniform foliage of his
-trees. The pi€turefque, on the contrary, is feen in the con-
trafted groups of Rubens; the crofling and winding of the
oftems, wredular foliage of trees, and in broken buildings 3 dué
ever accompanied with a beautiful choice; for,. as: before, ob-
ferved, if the picturefque was to be feparated from’ the beauti-
‘ful: there would be nothing left worthy the dignity of painting.
The erand ftyle requires the greateft fimplicity of conduét :
the rejection of all. things little is neceffary to its completion,
- not only as’ to difpofition, form, the minutize of ‘colour and
effect, but'to the total difregard ofiallthe trickery of penciling :
givlsveg above
7

On Paintings 37.

above all, if our fubje& is lofty, we muft, be careful not to
admit any thought that is trifling or mean; a fault many. of
the old maflers are not entirely free from,

©The drapery fhould partake of the fame great character
all the minute. parts muft, be rejected, the folds fhould be
broad and fimple, poffefs. an eafy communication, and grace-
fully followieach other as by chance.

The application of thofe flyles muft depend om the nature
of the fubjeét all together ;, the choice of the Roman. fchool
required a fimplicity of conduct which muft neceflarily run
through the whole picture. The fubjeés of the Cartons
would fuffer by a deftruCtion of the unity, from changing the
character of any part: the unaffected compofition, folemnity _
of colour, the broad and fimple folds of the drapery, form a%
whole that would be deftroyed. by attaching fhowy colour, or
changing the charaéter of the compofition or drapery to the
picturefque. . But fportive feenes, feafts, proceflions, and
marriage ceremonies, fuch as were principally chofen by the
Venetians, perfectly agree with that pictnrefque efle& arifing
from fplendour of colour, oppofition of light and fhade, con-
traft, and yariety of draperies.

This character appears to arife (as before obferved) out of
the very nature of the fubje&t. Who that wifhed to repre-
fent an aflaffination would introduce {plendid colours, or
great vivacity of light? On the contrary, would he not ra-
ther ufe fad and folemn, ones, with darknefs, obfcurity, and
great depth? 49 Oe

What, has reduced ,the} Venetian fchool, is. want of ex-
preflion. Paul Veronefe, in his pi¢ture of Mary Magdalen
anointing the feet of Jefus, has made it a mere eating-match
of Venetian fenators; ‘arid Tintoret, in his Marriage at Cana,
has made the company f{carcely notice the miracle of turning
the water into wine. |.

True hiftory {hould never have its gravity difturbed by any
improbable or impoflible circumflance. What can be more
abiurd than Raphael’s flying apofles in the Attila, the an-
gels in the battle of Conftantine, or St, Cecilia in the fame

iéture with St. Paul, St.John, St. Auguftin, and Mary

agdalen? The fame artift in the School of Athens has
confounded all the cireumftances of time and place. How
unlike is the conduét of a creat modern artift, who, in bring-
ing together a number of great chayaclers that lived at re-
mote periods from éach other, has wifely placed them in
Elyfium? In the picture by Titian, in the church of ‘St.
Francis in Venice (formerly alluded to), we find the Virgin
- C3 and

38 On Painting.

and Child, St. Peter, St. Francis, and Venetian fenators, to
the entire deftraGtion of chronology. | ebs
Thofe who choofe to exert their fancy had better invent
their fubject altogether, and not falfify'a fa by going: to
true hiftory, where invention can never juttify the itroduc-
tion of allegoric fiction. It detraéts from the merit of Con-
ftantine as a conqueror, by bringing the hoft of heaven to
his aid: without it we may fuppofe he could not have over-
come his more powerful partner’in the empire. But the
higheft joke’ is to find Heliodorus plundering the temple of
Jerufalem (as related in the fecond book of Maccabees), and
pope Julius prefent as a fpectator.
& I Jofe my patience, and I own it too,
When works are cenfur'd not as bad, but new 5
While, if our elders break allvreafon’s laws,
Thefe fools demand not pardon, ‘but applaufe. Pore.
Without racking our invention for fables above the com-
prehenfion of the vulgar, there are many fine’ moral {tories
for the practice ‘of, thofe who can afford'the time and expenfe
neceffary to their completion; fuch as the patient refienation
of that firft of mortal men, Socrates, at his death ; Curtius
leaping into the gulf; the Decii devoting themfelves for.
their country; the fudden reverfe of fortune in Marius at the
ruins of Carthage; the folly of Candaules in expofing his
wife’s beauty to his friend Gyges ; the defire of fame in Caefar
weeping before the flatue of “Alexander ; the virtue of ‘Pho-
_cion in refufing the bribes of Alexander; and the piety of
Eneas in preferving his father from the flames of Troy ;
with numberlefs others that muft occur to every one’s recol-
JeGtion. inte
The Florentine and Roman fchools have feized on the moft
prominent parts of the arts, and, having perfeéted them, left
but little to do for thofe who followed beyond embellifhing :
whatever was ftrong and forcible they feized im their mighty
‘grafp; hence thofe who have fucceeded them as they po-
Jithed have loft vigour and expreffion. The Caracci at-
tempted it, and with fome of their fcholars were often fuc
cefsful, and for dignity and expretfion ranked next after the
above great {chools. The Venetians appear fcarcely to "have
thought of it in the rich buftle of their pictures. | Rubens
among the Flemings ranks firft: and when the Dutch at-
tempted at expreffion it was always low and vulgar; Rem-
brandt was fuch, with a defperate bad choice of figure.
Raphael for expreffion jufily ranks before any other painter,
of which there are fine examples at hayd in the Cartons. at
Windfor.

On Painting. Ei

Windfor caftle, and which by the firt judges are ranked
among the beft of his works, if not the very beft. They
are unqueftionably preferable to any of his pictures in the
Vatican, for purity of invention and hiftoric truth. His
eafel pictures are generally poor,

» By expreffion we do not confine ourfelyes to the face
merely, but to the jufinefs of the general aétion. That ex-
reflion is juftly placed at the head of the art is evident from
its difficulty, for to exprefs well we muft in ourfelves feel thes
paffion, we wifh to reprefent. He who withes to wring an-
ather’s heart with anguifh muft feel as exquifitely himfelf:
hence the neceffity of recurring to nature, and not depend-
ing on the feelings of another, as the manuerift ever mutt.
We ihall obtain but little advantage in this inftance from a
model : we mutt therefore recur to ourfelves; and in fo doing
the looking-glafs will become our beft friend: for, as Pope
obferves,

They beft fhall paint them who can feel them moft,

- The paffions, as they are called, by Le Brun are over-
charged, fo much fo as to have become caricatures. There
is no laying down rules for what muft ever depend on the
feelings. Next to nature, the antique heads of the Laocoon,
the dying Alexander, the Niobes, and many others, will be
well worth confulting: but expreffion muft be general; we
fee agony in the fingers and toes of the Laocoon as {trong
as in the face. Domenichino and Pouffin were great in ex-
preffian; but, as before obferved, Raphael is the firft mo-
dern.

It would be an unpardonable negleét to overlook a work
of Britith art, that for expreflion would difpute precedence
with the beft of the Roman fechool. Where fhall we fee pa-
ternal defpair reprefented with more force and truth than in
fir Jofhua Reynolds’s count Ugolino, or the horrors of death
pronounced in a more determined and ma(terly manner than
in the children? We need fay no more: Sweetnels and Truth
were his handmaids; and’when be died the Graces would no
longer remain on the: earth. Where encouragement has
been ‘offered, the Britith artifis have done their duty: in
portrait and land{cape they equal, if not exceed, the bett;
and in hiftory fome works have appeared honourable in the
higheft degree to the nation. They will be fufficient to fhow
to pofierity the powers of the art in the time we live: a few
good works are enough, perhaps, in an-ungrateful age *. .

© * T am juftified in“ufing ‘the words ungrateful age, by the thameful
negleét thown at the fale of Macktin’s pictures by Britith arcifts, Art,
foi C4 like

45 On Painting.

If we with to know much, we muft {ee many things of @
kind, that by comparing them we may.acquire a more per
fect idea of the thing than the real object conveys; and thofe”
ideas we are bound to improve till we underftand the true
principles of general nature, or unaccompanied with thofe?
peculiarities that mark the defects of the individuals in each
fpecies. OTe

When we have determined on a fubject, we muft with all!
due expedition make a fketch of the principal perfons con’
cerned in the event, or whatever conftitutes the feature of
the pigéture, without regard to drefs or any of the leffer in-’
cidents, as much of the fire and fpirit of the actions, as
well as the grandeur of the whole, depends on’ the firft
impreffion. We mutt then do by our fketch as Virgil faid
he did by his works, ‘* lick them into fhape;” for, as the
firft part depends on the imagination, fo the fecond is the re-
fult of judgment: we are then to prune or add till the whole
comes into perfect ordonnance, choofing fuch objects as are
ftrikingly noble or beautiful, and adding fuch acceffory cir-

cumftances as. may beft contribute to illuflrate the ftoryo’

In our progrefs with the fketch we may add a fecond or third
group, fettle the dreffes and the back-ground, whether land-'
{cape or architecture, the difpofition of the maffes, and com-
plete the whole by flightly tinting it.

We are bound to preferve a whole throughout our work,
as well as an unity of time and place: we fhould therefore
avaid every thing local; even a well-known face or figure:
deftroys intereft, by rendering the work familiar.

Laireffe whimfically defcribes a picture of the deluge,
painted by an artift of his time, as made up of abfur-~
dities. Among other things jumbled together is) ‘¢ ‘the
grave of Mahomet, rolls of Virginia tobacco, a cardinal’s
cap, a childin a gocart, pickled herrings, a fmutch-pot and
pencils, all the toys from a Nuremberg toy-fhop, the re-
cords of the imperial chamber at Spire,” and, to crown the
whole, ‘* the Vatican,’’ and the artift’s own dear {elf §* fit-
ting on the fore-ground fketching every thing after the life.’”
The man muft be ignorant indeed who could .be guilty of

like beauty, having once withered, can/ never be-reftored. Confantine,
with all his wealth and power, could not refufcitate it, but was obliged
to rob antient Rome to adorn his new city.. Roufe, countrymen, roufe !
you will add to your own immortality, and give vigour to the labours of
the artift, by encouraging the noble walk of hiftory painting. How re-
nowned have the popes Julius and Leo, with the Medici, become from
fo doing! The prefent opportunity loft may never be regained... Why
fhould we not contend for the empire of wifdom.as well as of the fea?

fuch

Oi Areental Mercury. 4t

fuch grofs’ errors. An artift’poffeffidg common fenfe will
never act fo abfurdly as ‘to mix in the fame picture things an-
tique ‘and modern} an error common among the Venetian,
Flemifh, and Dutely mafters.’ tot Lala cae

“If the fabje& we mean to handle lies in Esypt, Athens,
er Rome,’ Jet us endeavour to tranfport ourfelves thither by
the warmth and activity of our imagination, and, by remoy-
ing every thing local, lead the fpectator through the delieht-
ful and ‘magical mazes of fcience, fo that he may actually

°

imagine the {cene tranfacting before his eyes.

(De bt. Si

VI.) Extrait’ of a Memoir on Argental Mercury.' Read
_~ before! the French National Inftitute, by Co CordDIER,
~ Engineer of Mines*.

4 WE: mineral called formerly native amalgam of filver,
and which ‘ince the labours of C. Hatiy is now known under
the name of argental merciry, is one of thofé natural me-
tallic combinations, ,the mineralogical and “chemical pro-
perties of which had -been the leaft perfectly deferibed and
examined. It'is however probable that an accurate know-
ledee of this fpecies would have been obtained, had not its
great rarity prevented chemi(ts from facrificing the only fpe-
eimens of it which they pofleffed in order to fubje& them to
complete examination. The places where argental mercury
is found are the mines of Rofenar in Hungary, thofe of Morf-
feldt in the ci-devant Palatinate, now the department of
Mont-Tonnerre, and particularly thofe of Mufehel-Landtbere
in the fame country: thefe are the only mines by which it
has been hitherto furnithed.

Though this mineral is at prefent too rare to be the object
of the labours of the miner, it will be feen that it deferves the
attention of the mineralogi{t, and to make a figure among
the moft remarkable of the metallic fpecies.

Argental mercury is found always diffeminated throughout
the mafs of the veins, fometimes in very thin leaves which
fill up the fiffures, fometimes in {mall eryftals totally engaged
in the matrix, or entirely infulated in the cavities.

This mineral fubfiance has the colour and_refplendence of
filver or polifhed tin, or rather more frequently of liquid
mercury, becaufe it almoft always retains at its furface a thin
firatum of the laft mentioned metal.

Its regular forms are the dodecaedral-rhomboidal, and all
_ its modilications,

* From the Journal des Mines, No. 67.

The

4% Qn Argental Mercury.

The fmall lamellaform leaves; of argental mercury, are for
the moft part bent, and follgw the undulations of the rock. to,
which they are applied. Their furface is generally {mooth,
and polifhed, but much lefs than that of its cryftals. This
metal is eafily feratched by a piece of fharp-pointed fteel. By
feraping it lofes almoft all its fplendour, and. becomes, dull,
When rubbed.on copper.it leaves a white metallic trace,, It
is brittle and eafily broken: its contiflence approaches. to.that
of martial pyrites. Its fracture is conchoid, and exhibits no,
appearance of lamine. The fragments, of it are, indeters
mined, with very obtufe edges.

{ts {pecific gravity, determined from a mean of feveral ex-
periments, is 14'r1925 argental mercury therefore, next. to
platina and gold, is the heavieft of bodies... When this mi-
neral is heated at the blow-pipe, the mercury becomes. vola-
tilized, and a fma'l button of filver may be eafily obtained.
_. The varieties of the regular forms dre, 1{t, The’ perfe&
rhomboidal dodecacdron (fig. 1. Plate I[1), ‘The incidence
of the two contiguous faces is 120°. , The cryftals, not being
{ufceptible of any mechanical divifion, it is not!poflible ta
know precifely whether this folid be the primitive) form,of
argental mercury, as is probable, and as we thall fuppofe it
to be,. in order to have the exprefiion of the laws of decrey
ment and the value of the angles. This fuppofition can pro-
duce no error, beeaufe the reiults of the calculation»may be
eafily transferred, fo.as.to apply them to the o¢taedron, the
tetraedron, or the cube, which aré, the only other, forms
poffible. jhiot

ad, .The dodeeaedron truncated on the fix folid angles
compofed of four, planes. The-fix new faces are prodiced in
virtue of a decrement by one row : they belang to the eubey
and make with the faces of the primitive form angles of 135°,
According to the ingenious method of C. Haiiy, the abridged
expreffion of the laws of decrement which produce this

be

form is P_E.

"3d, The fame as the preceding, the place of each ridge of
which is fupplied by a facet making an angle of 150° with
the adjacent primitive face : thefe new facets take place by the
fubtraGtion of a row of mdlecule on all the edges. Its ex-

i) Ba |
preffion is P BE,
1

4th, The dodecaedron truncated on all the ridges and alf
the folid angles, and having new facets on the edges of the
truncatures which take place on the edges, and the folid
angles compofed of four planes. ‘This form, which per bie

eel

On Argental Mercury. 43

been before obferved, is the moft complex ofall thsfe exhi4
bited by mineral fubftances, Itis;produced :by the interfec-
tion of the faces which belong tothe following: fix kinds of
regular or fymmetric folids, viz. the’ cube, the | octaedron,
the rhomboidal dodecaedron, ‘the folid: with:24 trapezoidal
facets, the folid with 24 ifofceles triangular facets, and the
folid with 48 fcalene triangular facets. The complete cryflal
is terminated by 122 faces., The expreffion|of this form,

reprefented fir. 2, is: P BHAEE,

ne ) '

The incidence of the faces of the, primitive fom, with
thofe of the oftaedron is 125° 15’ 52/"s with thole of the folid
having 24 triancular facets is 153 287 4/5 with thole of the
folid Having 48 faces 16° 53” 36".

Hitherto no complete anatomy of argental mercury has
been publithed ; mineralogifts were fatisfied with acquiring
an ‘approximate knowledge of its compofition from fimple
experiments: it was therefore of importance to determine
with accuracy the elementary principles of this mimeral, and
to fix the proportions. This analyfis was attended with no
kind of difficulty *.

Sixty parts of this mineral were expofed in a crucible to
_ the ‘aétion of a low heat, which was fucceffively increafed,

and continued as long as was neceflary to volatilize all the
mercuty. The cryftals, without fuffering any fenfible lofs
of volume, were changed into fpengy maffes, which to-
wards the end of the operation funk down and united into a
metallic button: the weieht of this button was found to be
16°5 parts, from which it was concluded that the weight of
the mercury volatilized was 43°5.

This button was perfectly malleable, and had all the ap-
pearances of the pureft filver. To afcertain its purity it was
expofed to the aétion of nitric acid proved by nitrate of filver,
The folution was effected without any refiduum. re

Oxygenated muriatic acid was poured into the folution,
and the precipitate of muriate of filver was collected on the
filter. The liquor tried by carbonate of potath furnifhed no
precipitate; the filver then contained no foreign metallic
fubftance.

In regard to the ftate of the mercury in its combination,
it is certainly not neceffary to prove that it exifts in a folid
ftate. ‘To be convinced of it, nothing will be neceffary but

* The ery tals fubjeféd to analyfis were covered with a fratum of
Jiquid mercury, which was removed by. prefling them between the fingers

in foft War,
to

44 On Argental Mercury:

to confider} firftp that:it forms almoft three fourths of the
whole! mafs; in!the next> place, that the fpecific'denfity of
the natural combination not only furpaffes, by a great deal,
the mean {pecific denfity'of filver and liquid mercury, but
alfo thatiit’ 1s: much more confiderable than that of the latter
metal, whichis the heavier-of the two. The {pecific gravity
indeed of the: combination, calculated according to the for-
mula. of (C. Hatiy,- would be only 12*5448, fuppofing the
mercury liquid, whereas itis 14711925, that of the mercury
is only 13°5681. | Nai a hep ,
A hundred parts of argental mercury, folidand. |
eryftallifed, contain then of folid mercury - - 72*5,
SUIVER sy yer oe ee ian aah ae aS

100
_ Two other trials, made indeed with quantities lefs confi-
derable, gave abfolutely the fame proportions. . .

_ The identity of the refults of the analyfis of this mineral,
its peculiar fpecific gravity, its faculty of cryftallizing, its
confifience, and all the other mineralogical characters be-
longing to.it, evidently prove that it ought to be confidered
as a real chemical combination, poffefling fixed and invari;
able proportions, and that it is with propriety that, a parti-
cular fpecies has. been formed of it in the mineralogical no-
menclature. ‘

It may be of, utility to remark here how improper the de-
nomination of native amalgam was to denote this mineral
fubftance... The name ftill. employed in chemiftry and the
arts does not denote a folid combination, but. a pafte-like
mixture, compofed. of exceedingly {mall cryftals of argental
mereury, adhering to each other by the medium of a certain
quantity of liquid mercury... The confiftence of the mafles
of artificial amalgam is even very variable: it may be ine
creafed or diminifhed at pleafure, fonretimes. by adding mer-
cury, fometimes by taking away a part of this metal, inter-
pofed by means, of a proper filter, fuch as a piece of fham-
amoy Jeather. It is the difficulty, perhaps, of feparating
entirely the excefs of mercury in the folid combination that
has occafioned @ belief that filver and nyercury may be com-
bined in all proportions: this opinion feems to, be as uns
founded as that m confequence, of which arg, rendered
ductile by the means of water, was confidered as a real
combination, the proportions of which might be indefinitely

varied. » It is proper to add, that at the common tempera-

ture argental mercury 1s always perfectly folid, and -befides
m that

On a neso Variety \of Epidotes a5
that it is infoluble in liquid-mereyry: this has been afcer-
tained by experiment. Heh;
~ An exact knowledge ‘of the fpecifie denfity' of arzental
mercury, as. wel] as of the proportions of its two component
principles, has fugsefted the idea’of! making fome refearches
in regard to the denfity of folid merctiry: © Chemifis have fet
out with the fuppofition that the nioléculz of the two ‘fietals
experience no dilatation nor penetration in ‘combining :
knowing ‘the {pecific ‘gravity of filer’ “to-4449)" that of
argental mercury = 14°11g2, and the ratio of ‘the two
metals +3, it will be fqund:that.the fpecific gravity of folid
mercury ought to. be 76°2662. In the cafe of there being a
penetration of moleculz,as is probable; the teal \denfity would
he fomewhat lefs: on the other hand, if there be dilatation,
‘it will be found to be more confiderablé. In’a Wword;) this
approximative ‘refult ought the lefs'to be neglected,’ as it is
probable that it will be always very difficult to’ attain diredily
‘to an eftimation perfectly exact. jit tf ISN. ati

FS

VII... Ectrad of a Natice, read, im the French National In-
Jiitute, on a new Variety of, Fipidote, . By CHAMPEAUX
and CRESSAC, Engineers. of Mines *,
- WHA "Vadsspad)

Tx E fubftance which fornis the obje& of this’ notice|was
found in the primitive chain which’ traverfes the country of
the Grifons, and’ unites the mountains of St,Gothard to
thofe of the Tyrol! *! 2 £root ola bot at haw i
It has always been fotind united to avariety of red garnet,
which Sauffure has deferibed + as a particular fpecies. under
the name of hyacinth de Diffencis.. ' To completethe\defcrip-
tion of) this {pecies, ‘he, gives a fhort.defcniption .of the, ful
fiance which forms the fubject of} this: article, jand he. gives
it the name of phrenite, becaufe he thought he could diltin-
guith in it charaéters which brought it near to the phrenite
of Oifans, . »« )
In this defeription we fhall follow the method adopted, by
» profeflor Haiiy. od ,

Effential Chara€tter.
Divifible in a dire&tion parallel. to the planes of a right
thomboidal prifm,, which form) with each other angles of
314° ,37' and 65f 23’. yy
| * From the Fournal des!Mines, "Now 64}.
Ne 4 Voyage ‘dans ies’ Alpus, 6.1902. y hye
: Phyfical

-

46 On a new Variety of -Epidote,
Phyfical Characters.
1, Specific gravity 3°3739.. This character was proved on, the
pureft fragments that could, be procured. EAT
o> Hardnefs... It eafily feratches glafs; it is.with difficulty
{cratched by quartz ;. {trikes fire with fteel. a
Tranfparenzy:,, Pellucid on the edges.
Colour... Bright. gray... 4... yet
Eleéfricily. .None.by heat 5, acquires none by,long cons
tinued ‘friction. :

TD

;

. a Geometric Charakiers.

4 Primitive form. ;, A; wight, prim with rhombal bafess
inclination of,the planes Mand. T of the, prifm (fig. 3,
Plate FIL.) 114° 37’ and:,65°.23'.. The divifions parallel to
the planes are, generally very clofe; the laming are: feldom

obferved.in thé direction of the bafes. Sten ae
Stru&ure. Very fenfibly lamellar: the natural: joinings
feem to be fomewhat clofer in one direétion than in another.
Fradure.-Cenchoid, fhining, with fmall. cavities: it
takes place only in one direction, that of the bafes; in that
‘of thé planes of the prifm nothing is obtained but ‘lamina,
which’ manifeft the ftruéture. : wart 3
' Chemical Chara€ers.

With the blow-pipe.. On. the fir application of: heat the
colour beconres Jefs dark; the angles and the ridges then fufe
into 2 yellowifh enaniel, which grows brown in a continued
heat, and is converted into feoria: if a thin plate be fub-
jected fo experiment, it becomes.-corneous before it is fco-
rified. I i riers batho ts eGR)
Acids, cold. Acids haye no a&tion on it... agate

It refults from this examination, and particularly the ‘con-
fideration of the effential chara&er, that the fubftance in
gueftion belongs to the epidote; for it can be divided in a
direction parallel to the planes of ‘a right rhomboidal prifm,
which form with each other angles of 114° 37! and 659 23’.
It fometimes happens that there is obferved above the planes
of the prifm facets oblique to the axes, which might give
reafon to fuppofe that they are parallel to the bafes, and
thence be led into an error refpeéting the determination of
the primitive form; but an attentive examination {hows that
they belong ‘to other cry(tals-which penetrate the former ;
and befides, the examination of a form, fufficiently promi-
nent to admjt» of applying to it the laws of ftruture, has

proved that obfervation agrees with calculation,

This

tt

On anew Variety of Epidote. ' dy

{. This form, which: has not: yet been defcribed among the
known varicties of the epidote, refults:
/) aft,’ From a deerénient by-one row on the edges G of the
prifm (fig. 3.) correfpondisig itd the acute angles of the bafe.
ad, From:a mixt decrement ion the: left, by fourirows in
breadth and:three in height, on the other edges H; »
3d, From»a decrement by three rows to! the ileft on the
fame edges. This is that which-conttitutes the new variety.
~( Phe! preceding laws do not: mark entirely:the planes M

v4th, In‘ the laf place, ‘from aidecrement by ote row’ on
the acute angles B of the rhombus: of ‘the qbafez ):The Jatter
Teaching its lirits;:makes the face P difappear entirely.» ©:
) It follows from»this: ftrugture that! the charaéteriftic fign
209 VIISIC Ba sinigat Bi ys eyase ! arene
of the cryftal will be-G M “H HTE 3 and the form pro-
* . “ Fa | 4 es ee , hey F
duced being a prifinof ten planes and diedral fiimmits-(fic.'4.),
we may thence deduce the denomination of qtiadritecimal,
which will exprefs the four faces’ of the fimmits and the ten
‘of the prifim. parte Ree ene hg

Caleulation has given for the inclination 6f the ‘face x pro-
duced on the adjacent plane M 163° 23’, and on thé declin-
ing plane T 131° 177; refults which are agreeable to thofe
obtained by geometry.

Independently of. the form. already defcribed there ‘have
-beeit, obferved alfo fecondary eryftals prefenting ‘at their fur-
face parallel ftrie. This, no doubt, is. that: deferibed by
Sauffure in the following words: firiz, as if in the form of
baftions, In a word, we may mention as pferdomorphic the
forms of emarginated garnet, to which, this.epidote of Dif-
fentis has been affociated; for fometimes it covers it entirely
by being moulded. over it, and. fometimes, it, is .completely
stron by it in fach.a_.manner,, that, one of, the. two fub-
flances cannot be feen but by the fracture of the other.

‘The obfervation of this new variety proves that, the deter-
‘mination of mineral {ubftances merely by their exterior cha-
racters is excecdingly detective; for the latter, by, its, faces. is
very difiin& from the fpecies to which, it belongs, but the
geometric characters affign to it in the methodical fyftem its
‘real place, AL a Key

We fhall remark alfo that the cpidote is a fubfance the
varieties of which differ from each other -aédording to the
countries: where they have been found: tobe convinced of
this, nothing will be neceffary but to. compare that of Dau-

phiny with that of Arendal and that of Diffentis, Their
afpedt

as On a Variety of carbonated Lime,

afpeét is fo peculiar that nothing cam prove their identity but
analyfis and the laws of ftruéture.

We fhall compare this new variety of the epidote onl with
the phrenite, becaufe it is under this name that it is defaritied
by Sanffure : it differs from it by its f{pecific gravity in the
ratio of 33 to 36, and by its ftrugturey as it exhibits evident
fections in two directions, while the phrenite exhibits. | only
one: in a word, it is not electric by heat.

The ‘rock which accompanies it-is compofed of the’ fab-
ftance of the garnet, the epidote itfelf, calcareous ftone, and
quartz. -Thele elements fometimes are'in proporuions.nearly
‘equal; but it happens for the moft part that the matterof
the garnet predominates. In fome fpecimens the epidote is
difpofed in thin zones between cryftals of garnet, om which it
is moulded, it appears .alfo in amorphous maffes pretty vo-
Juminous. Nothing certain can be faid in regard to its pofi-
tion ; butit may be affirmed that it-is found i in the cavities or
fiflures of primitive mountains. We do not think that it has
ever yet been found in its proper place by any naturalift ; and
the cafe is the fame with the other produétions of St. Go-
thard. ,. The dealers in cryftals go in queft of them,, and fell
them to travellers.

VIIT. Note on a Variety of carbonated Lime found near Port

Seguin, Department of Vienne. By C, Cressac, Engi-
necr of Mines*.

Tu Is sabietys which has not yet been dateribed seats

from a combination of the three following laws of decre-
‘ment:

ift, That which ahauliees the prifmatic by a decrement of
two rows in the inferior angle ¢ (fig. 5. Pl. IIT.)

ad, That which produces the inverta by a row on the right
“and left of the angle E,

3d, That which produces the equi-axis by a dectemet of
‘one row on the edge B:

The reprefentative fien of this variety, reprefented fig. 6,
is ¢ E rE B; it has been called by C. Haiiy co-ordonate
carbonated lime. .. This. name is, deduced from the pofition of
‘the facets. apiaduced by the three decrements in qusition-

* From the Journal des Mines, No. 67.
; Thefe

On certain Stony and Met alline Subjtunces. 49

Thefe facets are fituated.on the fame fide, and are feparated
by parallel ridges.
Inclination of ¢ to g 116° 33! 54!
-ofctof 153 26 6

ofgtof 143 7 48.

IX. Experiments and Obfervations on certain Stony and
Metalline Subjiances which at different Times are faid to
have fallen on the Earth; alfo on various Kinds of Native
Iron. By Epwarv Howarp, Eq. F.R.S.

[Concluded from p. 336 of our laft Volume. ]

Tu E conneétion which naturally exifts between one mafs
of native iron and another, immediately turns our attention
to the native iron in Siberia, defcribed by Pallas; and this,
we are told, the Tartars confidered as a facred relic, which
had dropped from heaven. The nickel found in the one mafs,
and the traditionary hiftory of the ‘other, not to compare
the globular bodies of ftone from the Benares with the glo-
bular concavities and the earthy matter of the Siberian iron,
tend to the formation of a chain between fallen ftones and
all kinds of native iron. How far any real affinity exifts be-
iween thefe feveral fubftances, very obliging friends have af-
forded me an opportunity to form fome judgment. Iam
indebted to Mr. Greville and Mr, Hatchett for portions of
almoft every known native iron; and the count de Bournon
has done me the favour particularly to deferibe them as
follows.

Defcription of various Kinds of Native Iron, By the Count

de Bournon.

The great number of particles of iron, in a perfectly me-
tallic ftate, contained in the {tone from Bohemia, and the
faid particles being fo near each other, naturally lead to
fome reflections refpecting the exiftence of native iron, which,
by many mineralogifts, is ftill confidered as problematical.
Let us fuppofe for a moment, that thefe particles of iron were”

to approach {till more nearly to each other, fo as abfoluteiy

to come into contaé, and in that manner to form a kind of
chain, folded upon itfelf in the interior part of the fubftance,
and leaving a great number of cavities between the links of
the chain fo folded, Let us then fuppofe, that the earthy:
fubfiance with which thefe cavities are filled, being very
rous, and having but a fmall degree of confifience, fhould
may happen Et a yariety of caufes) be deftroyed. It ig
Vou, XIV, No. 53. D plain,

50 Experiments and Obfervations

plain, that if fuch a deftruétion were to take place, the itox
alone would remain; and, being thus left bare, it would ap-
pear in the form of a mafs, more or lefs confiderable, of a cel-
Jular texture, and as it were ramified ;-fuch a form, in fhort,
as that in which moft of the native irons we are acquainted
with have been found. May it not be fair to attribute to
fuch an origin the native iron found in Bohemia, a fpecimen
of which was prefented by the Academy of Freyberg to baron
Born, and which came, with the reft of his collection, into
the hands of Mr. Greville?) May not futh alfo, notwithfiand-
ing the enormity of its bulk, be the origin of the mafs of
native iron found in Siberia, near Mount Kemirs, by the
celebrated Pallas ?

We have already feen, in the'refults of the analyfes made
by Mr. Howard, of the various ftones above deferibed, that
he contiantly found a certain proportion of nickel mixed with
the iron they contained, This circumftance recalls to our
notice the obfervations that were made by Mr. Prouft, fome
time ago, refpecting the mixture-of nickel in the native iron
ef South America; and tends to give fome additional fup-
port to the opinion hinted at im the foregoing paragraph.

The circumftances juft mentioned naturally gave to Mr.
Howard,’ as well as to me, a defire to know whether the na+
tive iron from Siberia, and that from Bohemia, were alfo
mixed with nickel. Mr. Howard, confequently, loft no time
in proceeding upon this important inveftigation. ‘The native
iron ef Siberia prefents fome very interetting peculiarities, and
has often been referred to, but has not yet been properly de-
{cribed; it is therefore with great pleafure that I add the fol-
lowing defcription of it, and of fome other kinds of native
iron, to the defcription I have already given of the various
{tones faid to have fallen on the earth. :

I feel the greater fatisfaction in doing this, as the noble
eolleétion of Mr, Greville contains two fpecimens of this iron,
in perfect condition; one of which weighs feveral pounds,
and was fent to Mr. Greville by Mr. Pallas himfelf: on this
gccount, therefore, Tenjoy an advantage that many of the
authors who have fpoken of this iron probably wanted.

‘One of thefe pieces has a cellular and ramified texture, ana-
logous to that of fome very porous and light volcanic feoria 5
this is the ufual texture of the fpecimens of this kind of iron,
which are preferved in the various mineralogical colleétions
im Evrope. When it is attentively examined, there may be
perceived in it, not only empty cells, but alfo impreffions or
cavities, of greater or lefs depth, and fometimes perfectly
found, which appear evidently to be ‘the refult of the com-

9 _ preffion

NAR i cs .

on certcin Stony and Metalline Subftances. st

preffion of hard bodies which were fituated there, and which,
when they came away, left the furface of thefe cavities quite
fmooth, and having the luftre of polifhed metal. Here and
there, in fome of thefe cavities, there remains a tran{parent
fubftance, of a yellowifh green colour, of which I fhall treat
more particularly when I come to the defcription of the fe-
cond of the fpecimens above mentioned. It is very clear that
the cavities here fpoken of owe their exiftence to this trans-
parent fubftance ; and that the polifh of the cavities arifes
merely from the compreffion of the faid fubftance, and is the
natural confequence of its furface having been in perfect con-
taét with that of the iron. nA

This iron is very malleable: it may be eafily cut with a
knife ; and may be as eafily flattened or extended by means of a
hammer. Its ieeihé gravity is 6487 ; which,however, is very
much under that of iron which has been merely melted, and
has not been forged. The fpecific gravity of the native iron
of Bohemia, which is nearly as malleable and as eafy to be
cut, is {till lefs: I found it not to exceed 6146. This low
degree of gravity appears to be owing partly to the oxidize-
ment of the furface of the iron, and partly to there being,
in the interior part of its fubftance, a number of {mall cavi-
ties, which are often rendered vifible by fraéture, and which
have their furfaces alfo oxidized. The fraéture of this ‘iron
prefents the fame fhining and filvery white colour as the com-
mon caft iron known by the name of white caft iron: but its
nic is much fmoother and finer; it is alfo much more mal-

eable when cold. Bergman fays that this iron is brittle when
heated toa red heat. I have frequently tried it in that ftate,
and have conftantly found it to be malleable. The fame re-
mark may be applied to the native iron from South America,
and alfo to that from Senegal.

The fecond of the two fpecimens mentioned above, and
which weighs feveral pounds, prefents an afpect that differs,
in fome hefedts, from that of the preceding fpecimen. The
moft confiderable part of it forms a folid compaét mafs, in
which there is not to be perceived the fmalleft appearance of
pores or cavities; but there arifes upon its furface a kind of
ramified or cellular part, fimilar, in every refpect, to the fpe-
cimen already defcribed, ‘and every where completely con-
neéted with the fubftance of the mafs itfelf.

If the compaét part of this piece is examined with atten-
tion, it will be perceived that it is not entirely compofed of
iron in the metallic ftate, but that it is mixed with nearly
- an equal ie of the tranfparent fubftance of a yellowith

green colour, (fometimes alfo of a greenifh yellow,) already
. D2 {poken

5m Experiments and Obfervations

fpoken of in the defcription of the other fpecimen. This fub-.

{tance is mixed with the iron in fuch a manner, that if the

whole of the former could be removed, the remaining part

would confift merely of iron in the metallic flate, and would

prefent the fame cellular appearance as the preceding fpeci-

men, and the ramified or cellular part of the fpecimen now
efcribed.

This ftony part, feparated from the iron, appears in the
form of fmall nodules, generally of an irregular fhape, but
fometimes nearly globular: they have a perfectly fmooth and
{hining furface, fo as very often to prefent the appearance of
{mall balls of glafs; a cireumftance that has led many perfons
to fuppofe them the refult of a real vitrification. Some of
thefe nodules have feveral irregular facets, produced by the
compreffion of the iron in which they were inclofed; but I
have never obferved in them any appearances that could lead
me to fufpect they had the flighteft tendency whatever to
affume a determined cryftalline form.

This fubftance is always more or lefs tranfparent. It fs
fufficiently hard to cut glafs, but has no effeét upon quartz.
It is very brittle: its fracture is ufually conchoid ; but I could
perceive that it broke in any particular direction, in fuch a
way that I could confider the fra€ture as a natural one. It
becomes eleétric by friction. Its fpecific gravity is from 3263
to 3300. It is very refractory: I kept it, for fome time, ex-
poled to a degree of heat fufficiently ftrong to oxidize, to a
confiderable depth, the iron crucible in which it was placed,
without its having undergone any alteration, except that of
having acquired a greater degree of intenfity in its colour.
Its tranfparency was not at all diminifhed. I think, there-
fore, there is not the fmalleft reafon to allow any probabilit
to the opinion that it ought to be confidered as a kind of elafs.
Of all fubftances hitherto known, that with which it feems

io have the greateft analogy is the peridot, (the chryfolite of
Werner,) to which fome mineralogifts have referred it. The
refult of Mr. Howard’s analyfis of it is nearly the fame as
that of the analyfis of the peridot made by Mr. Klaproth,

The hardnefs and infufibility of this fubftance are nearly
the fame as thofe of the peridot ; but it feems to have a rather
lefs degree of fpecific gravity : that of two very perfect cryftals
of peridot I found to be from 3340 to 3375. ~The cryftalline
forms of the fubftance here defcribed, if ever we fhould be
able to determine them, would clear up our doubts refpeéting
the analogy between the two fubftances. If we confider the
compact part of the fpecimen now treated of, particularly the
ftrong connection that appears to exilt between the iron “

: the’

~

en certain Stony and Metalline Subjtances. 63

the tranfparent fubftance, and the great refiftance we experi-
ence when we attempt to feparate them, we cannot help being
furprifed, that almoft all the fpecimens of this mafs of me-
tallic iron that have been brought to Europe are in the cel-
lular ftate already defcribed, owing apparently to the total, or
almoft total, deftru@tion of the tranfparent fubftance. But, .
befides the fragility of this fubftance, the fpecimen in queftion
helps very much to explain the above circumftance, inafmuch
as many of the nodules of the tranfparent fub{tance belong-
_ing to it are in a ftate of real decompofition. Jn that ftate,
they are changed into a white opaque fubftance, which, upon
being lightly preffed or fqueezed between the fingers, crum-
bles into a gritty dry powder. This decompofition may be
obferved to have taken place in various degrees: in many of
the nodules, the fubftance is merely become friable, without
being much altered in its appearance ; whereas, fome of thofe
which are ina ftate of complete decompofition are of an
ochreous reddifh yellow colour: it is, however, eafy to di-
ftinguifh that this colour does not belong to them, but is
owing only to the oxidizement of the adjacent particles of
iron.

From the above obfervations it will not be difficult to con-
ceive the poffibility of the total, or nearly total, deftruétion of
the tranfparent fubftance; and alfo, the appearance the pieces
of iron muft naturally prefent when deprived of it. I cannot
help obferving likewife, that there appears to exift a very in-
terefting analogy between thefe tranfparent nodules and the

lobules I deferibed as making part of the ftones faid to have
Fallen on the earth. This analogy, though not a very ftrong
one, may lead us to fuppofe that the two fubftances are fimilar
in their nature, but that the globules are lefs pure, and can-
tain a greater quantity of iron.

The native iron from Bohemia is a compact mafs, fimilar
to the compact part of the large fpecimen of iron from Siberia,
which has juft been deferibed: like that, alfo, it contains a
number of globular bodies or nodules; but they are not in
fuch great proportion as in the Siberian iron. They are be-
fides perfectly opaque, and very much refemble the moft
compact of the globules belonging to the ftones faid to have
fallen on the earth, 9

¥

Examination of the Iron from South America,
~ TI have already obferved, that my experiments coincided
with thofe of Mr. Prouft. He obtained 50 grains of fulphate
of nickel from 100 of this mafs. ‘Fhe procels I have fo fre-
D3 quently

54 On certain Stony and Metalline Subjtancess

quently mentioned yielded me 80 grains of oxide of iron from.

62 of the metal; which indicates about 7+ of nickel, or about
IO per cent.

Examination of the Siberian Iron.

100 grains of this iron gave 127 of oxide of iron: hence.

it {fhould contain about 17 per cent. of nickel.
The yellow fubflance belonging to this iron was analyfed

in the fame way as the globular bodies, and the earthy parts,

of the ftone from Benares.
The proportions refulting from the analyfis of 50 grains,
and from fome previous experiments on other particles, were,
Silica - - - &: “s

27
Magnefia = - Z 13%
Oxide of iron = , 4 st
Oxide of nickel “ S =

49:

Examination of the Bohemian Iron.

26! grains of this metal left about 14 grain of earthy
matter, infoluble in nitric acid; and, by ammonia, afforded
30 grains of oxide of iron, inducing an eflimation of nearly
5 of nickel. ;

Examination of Iron from, Senegal, brought by General
O’ Hara, and given to me by Mr. Hatchett.

In this experiment, 199 grains of oxide were produced from
145 grains of metal: hence there may be an eftimation of
8 grains in 145, or between 5 and 6 per cent. of nickel.

It will appear, from a collected view of the preceding pages
and authorities, that a number of {tones afferted to have fallen
under fimilar circumftances have precifely the fame charac-
ters. The ftones from Benares, the ftone from Yorkfhire,
that from Sienna, and a fragment of one from Bohemia, have
a relation to each other not to be queftioned.

ift, They have all pyrites of a peculiar character.

adly, They have all a coating of black oxide of iron.

3dly, They all contain an alloy of iron and nickel. And,

4thly, The earths which ferve to them as a fort of con-
necting medium, correfpond in their nature, and nearly in
their proportions.

Moreover, in the ftones from Benares, pyrites and glo-
bular bodies are exceedingly diftinct.. In the others they are
more of lefs definite; and that from Sienna had one of its

: globules

oom

Confiderations on Dr. Huiton’s Theory of Rain. 55

globules tranfparent., Meteors, or lightning, attended the
-defcent of the ftones.at Benares and at Sienna... Such coin-,
cidence of circumftances, and the unqueftionable authorities
I have adduced, muf, I imagine, remove a!l doubt as to the
defcent of thefe ftony fubftances; for to difbelieve, on the
mere ground of incomprehenfibility, would be to difpute
mott of the works of nature.

Refpeéting the kinds of iron called native, they all contain
nickel. The mafs in South America is hollow, has conca-
vities, and appears to have been in a foft or welding ftate,
becaufe it has received yarious impreflions.

The Siberian iron has globular concavities, in part filled
with a tranfparent fabftance, which, the proportional quan-
tity of oxide of iron excepted, has nearly the compofition of
the globules in the ftone from Benares.

The iron from Bohemia adheres to earthy matter ftudded
with clobular bodies.

The Senegal iron had been completely mutilated before it
came under my examination.

From thefe faéts I fhall draw no conclufion, but fubmit
the following queries :

1ft, Have not all fallen ftones, and what are called native
irons, the fame origin?

adly, Are all, or any, the produce or the bodies of meteors?

And, lafily, Might not the ftone from Yorkthire haye
formed a meteor in regions too elevated to be difcovered ?

Specimens of the Benares and Yorkthire {tones have been
depofited, by the prefident, in the Britifh Mufeum.

X. Confiderations on Dr. Uutron’s Theory of Rain;
read before the Afkefian Society, in the Seffion 1801-2. By
Luke Howarp, E/g. FLL. S,

Ly an effay prefented to the Royal Society of Edinburgh,

and inferted in the firft volume of their Tranfactions, Dr.

Hutton inveftigates the rule directing the aétion and effects

of heat and cold on the atmofphere, in order to eftablith a

theory of rain on this principle, that the mixture of portions

of air faturated with water, and at differing temperatures,
will uniformly produce the condenfation of a portion of
water,

** This rule of condenfation,” fays Dr. Hutton, ** may
be applied to the theory of rain, which is the difiillation of
water firft diffolved in the atmofphere, and then condenfed
from that {tate of folution.

D4 ‘¢ The

56 Confiderations on Dr. Hutton’s Theory of Rain:

“ The caufe of rain, though often exerted, will not al-
ways prodice the full effeét; a fcanty condenfation of aque-
ous vapour preduces mi//s on the earth, and clouds in the at-
mofphere above: and taking the gradation from one extreme
of tranfparent atmofphere to the other of the denfeft cloud,
from the falling of the gentleft mift to the heavieft rain, hail,
and fnow, we have an indefinite variety of appearances, all
flowing from one fimple principle.”

On the vifible fteam produced by the breath of animals
and by heated water, in a cold atmofphere, the author re-
marks that this appearance is not the effeét of the genuine
principles of heat and cold; that, to explain it, the know-

ledge of a particular law is requifite ; and that the efleéts of -

heat and cold, in relation to air and vapour, are not uniform.
The law alluded to is thus Jaid down:

<* The diffolving power of air on water may vary in dif-
ferent proportions to the heat. The folution may vary as the
heat, or in a greater or lefs ratio, 1.e. the increments of
each may be conftant, or, thofe of the heat being conftant,
the increments of the folution may be accelerated or re-
tarded. f

«* This may be reprefented geometrically (fee fig. 4,
Plate III). Let CH reprefent the fcale of the thermometer;
am br, perpendicular ordinates, the quantity of water held
in folution by a given quantity of air of the. temperatures
aand b. Join mr, and draw the curves mgr, mdr: then
it is evident that the ordinates to m7 mark a folution varying
as the heat; the ordinates to mdr a folution varying in a
greater ratio, and to m gr in a lefs ratio than the heat.

‘¢ The ordinates to line mr, drawn from a point denoting
the temperature of the mixture, reprefent the quantity of
water contained (diffolved or not) in a unit of the mixture ;
for the ordinates mar are as the quantities contained in a
unit of air of temperatures @ and 4; and as upon mixture
the heat and water are uniformly diffolved (diffufed?), they
vary in the fame proportion, and may be expreffed by the
fame meature.

‘* Suppofing equable folution, mix equal portions of fatu-
rated air, temperatures 10 and 40; the mixture of tempe-
rature 25 is reprefented by of, which alfo reprefents the
quantity of water in a unit of the mixture, and the quan-
tity held in folution by a unit of air at temperature 25.

<¢ So two portions of temperature 40, being mixed with
one of temperature 10, the temperature produced 30 will be
exprefled by wg.

* In the curve mdr let equal portions of the folution at

6 49

‘
I ny 6.

Confiderations on Dr. Hutton’s Theory of Rain. 59

40 and at 10 be mixed; then 0 is the quantity of water
contained in this mixture at the mean heat 25, while oe is
the ordinate of folution: confequently ef is the quantity of
water that cannot be retained in folution in the mean tem-
perature produced by the mixture.

“ In the curve mgr let equal portions at 10 and 4o be
mixed ; and the ordinate being drawn in thé mean 25, sk ~
will be the whole power of folution, and the quantity of
water that air is capable of diffolving in this degree of heat;
but o p being the quantity of water actually in the mixture,
the air is underfaturated by the quantity &.

** Thus the actual curve of evaporation being known, the
effe&t of any mixture of two portions at different tempera-
ments may be afcertained. If the folution of water in air
increafes equally with the heat, there will be neither fuper-
nor under-faturation in a mixture of portions at different
temperatures.

<¢ If the folution inereafes with the heat but in a de-
ereafing rate, there will be under-faturation ; if it increafes
with the heat but in an increafing rate, there will be fuper-
faturation.

** The laft cafe applies to the phenomena of breath and
fteam * rendered vifible in mixing with air colder than them-
felves, and to various appearances that may occur in mixing
together feveral portions of air differently faturated with hu-
midity and at different temperatures: for it is mot every
mixture of air at different temperatures that forms a vifible
condenfation, this effect depending on the degree of fatura-
tion with humidity. But if two portions of the atmofphere,
both faturated with humidity, fhould be mixed, let there be
but a difference in their temperatures, a condenfation pro-
portionate to this difference will take place.

** At prefent, from the influence of the afcending fun,

* Aqueous gas at 212° (or fteam) produces vifible clouds in mixing
with air at a lower temperature; but fteam is not a folution of water in
air, neither is this appearance peculiar to it, but attends the cooling (in
contaét with air) of the tranfparent vapours of camphor and all volatile
oils, as well as of benzoic acid and other fubftances quite infoluble in air,
The fublimation of the latter very aptly exemplifies to a fpe€tator of it that
momentary produétion of fhow which has been witnefied when the ins
tenfely cold and denfe air of northern climates has been fuddenly admitted
into the moift and warm atmofphere of the apartments in ufe there.

Vifible team arifes from the differing, capacities of air aud of vapour for
caloric. The former, in acquiring temperature from the latrer, robs it of
a portion of its cozflituent caloric: hence a momentary reprodudtion of
water, which is afterwards depofited or diflolved according to circume

ftances, Note by the Author of the prefint Effay.
two

58 Confiderations on Dr. Hutton’s Theory of Rain.

two oppofite currents of air are formed in the fummer hemi-
fphere, one moving along the furface of the earth from the
pole to the equator, the other flowing above. Thefe oppo-
fite currents, while feparate, might pafs each other without
producing rain; but when fufficient portions are mixed, not

only clouds but fhowers will be produced, fince the fudden

formation of a mean degree of heat, in the mixture of two
portions of different temperatures, muft condenfe a quantity
of vapour fufficient to form rain.

«© Without this law of condenfation of evaporation nei-
ther rain nor dew could take place any where in the fummer,
hemifphere, perhaps not even in tropical Jatitudes: there
would be evaporation and ageneral tendency to faturate the
atmofphere with water, but the mixture of different portions
of air would only temper the faturauion without producing a
condenfation of vapour in the mean degrees of heat. At
night, from the influence of ‘the cold, the atmofphere
would become gradually clouded; this cloudinefs would in-
ereafe to a general diflillation of condenfed vapour, which
would be uniformly continued until the returning fummer
fhould change the ftate of condenfation to evaporation ; and
inftead of the beautiful return of feafons, tempered with va-
rious degrees of heat and refrefhing fhowers, fix months
rain and fix months drought would follow each other in an
invariable fucceffion.”’ ’

Such is the bypothefis which Dr. Hutton is willing we
fhould confider as the theory of rain, and which he proceeds
to apply to natural appearances ; feeming to experience no
creat difficulty in folving by it every problem that occurs, as
the folflitial, equinoGtial, and other periodical rains, the
comparative {tate of different climates and of land and. fea,
as to its frequency and quantity, &c. But, if, we exeept
afhort remark on hail and thunder florms (which feems only
to give occafion to a confeflion of our imperfect knowledge
of atmofpherical electricity), in no inftance does the doctor
avail himfelf of the aid of any other principle than the mix-
ture of currents of air in traverfing the irregular furface of
the globe, and confequent precipitation of water, to account
for the whole train of phenomena conftituting the fubje&t of
meteorology.

The fimplicity of this theory, the impofing air of a dia-
gram at its introduction, the ingenious and deferiptive man-
ner of the application, all contribute to render it fufficiently
plaufible. It is rather extraordinary that the objections urged

againft it by De Luc * fhould have extended no further than
* Idées fur la Météorologie, tome ii. p. 67+

it

Confiderations on Dr. Hutton’s Theory of Rain) 59

it‘ appears they did. It would however be readily granted,
I fuppofe; by each of thefe philofophers, that hypothefes,
of whatfoever kind, ought not to be admitted into fcience
without the moft rigorous examination, and that doubt has
a‘right to keep the door fhut until fome paffport of the de-
monttrative kind is obtained cither from nature or experi-
ment. A geometrical reprefentation of what may be is not
a fufficient foundation whereon to aflert what is a law of na-
ture, Let us therefore examine how far this theory, which
does hot appear to be fupported by any dire&t experiment,
will bear the teft of the excellent and decifive ones whereon
the doétrine of capacities has been eftablifhed by Black,
Crawford, and Lavoifier.

The author firft affumes, as a law of nature, the pofition,
that the folution of water in air increafes with the tempera-
ture (heat), but in an increafing ratio. On this be grounds
a fecond, the fubftance of which is, that if two portions of
air, faturated with water and at differing temperatures, ‘be
mixed, the mean proportion will not be foluble at the mean
temperature, and therefore a part will be precipitated.

The fi#ft pofition may be true, or it may not; perhaps no-
thing fhort of actual experiment can fatisfaCtorily afcertain
the actual curve of evaporation *,

The fecond depends entirely on conditions which the do€tor
has taken for granted in each of the three cafes of evapora-
tion ftated by him, and which, on the received principles of
caloric, can belong to no one of them. Thefe conditions
withdrawn, the theory of rain, like its fubjeét, falls to the
ground, and the diagram proves as unfubftantial as the bow
with which the fhower is decorated. To make this appear,
it is only neceflary to produce the following praétical refults,
which apply equally, whether we regard caloric as matter or
motion,

A homogeneous fubftance, or two fubftances having equal
capacities for caloric, being mixed in equal portions at un-
equal temperatures, the temperature of the mixture is found
to be in the arithmetical mean.

But heterogeneous fubftances, and thofe in other refpects
homogeneous, but differing in capacity, being mixed in like
manner, give a temperature which either exceeds or falls
below the arithmetical mean, and approaches towards that
of the two fubftances which poffeffed the greater capacity.

* Experiments decifive of this very queftion were made about this time,
and the refults prefented to the Literary and Philofophical Society of
Manchefter by John Dalton, efy. We ‘thall have occafion to notice his
paper further on. ,

The

~

60 Confiderations on Dr. Hutton’s Theory of Rain.

The capacity of water (which Crawford terms the com-
parative heat) being taken at 1,000, that of air proves by
his experiments to-be as 1,790, and that of aqueous vapour
as 1,550, at equal weights and temperatures.

Then if to dry air we add fucceflive portions of water at
increafing temperatures, we are forming a compound (not
merely heating a homogeneous mafs), the nature of which,
as in all other refpeéts, fo in that of the capacity for caloric,
mutt ftill continue approaching to that of aqueous vapour.

Now in any two portions of this compound, formed at
different temperatures, the capacities will differ. It. will
be lefs in that which was faturated at the higher tempera-
ture ; and whatfoever may have been the precife rate at which
the folution advanced at increafing temperatures, the mixture
of the two portions will not produce a temperature in the
arithmetical mean, but below it, as being moft influenced
by the drier portion.

Thus is the principal condition invalidated, viz. that por-
tions of faturated air at differing temperatures will poffefs,
after mixture, a temperature in the arithmetical mean. .This
argument may appear at firft fight ftill to favour theiconclu-
fion refpecting the mixture in the curve mdr, fince, if pre-
cipitation take place at the mean temperature, much more
fhould it at a lower than the mean: but perhaps it may be
eafy to demonfirate, on the fame principles as before, that
the temperature of fuch a compound, as it refults from this
circumftance of mixture only, will in no cafe affeét the
flate of folution, and that neither fuper- nor under-faturation
will enfue therefrom.

We will take for this purpofe the curve mdr, and exa-
mine the real circumftances of a folution advancing with the
temperature but in an accelerated ratio; premifing that the
queition regards the effects of heat (caloric) only as the caufe
both of increaled temperature and increafed folution, and
that, according to Crawford, equal additions of this (the
capacity of the receiving body continuing unchanged) pro-
duce equal expanfions in the common thermometer.

That the folution of water in air goes on increafing with
the temperature of the compound is true, and itis equally
fo that it increafes at the expenfe of that power which gives
the temperature ; for water held by air is itfelf in the fate of
gas, and gas of whatfoever kind requires a large proportion
of caloric for its conftitution, which is not at all meafurable
by the thermometer.

Suppofing therefore a unit of dry air at a certain tempes
rature to confilt of 0,005 meafures of liquid bale and 0,995

caloric,

Confiderations on Dr. Hutton's Theory of Rain. 6%

caloric, and that one part of caloric will raife its temperature
one degree in any part of the feale ; if we with to convert this
into a unit of yvoi// air at the fame temperature, it will not be
fufficient merely to add.the proportion of water, fuppofe 0,001 3
for this water, being itfelf a Liquid bafz, will require nearly as
much additional caloric to cenititute it gas, as the portion of
air which was neceffarily excluded. from the unit took away
with it. When we haye added this proportion of caloric
(which would have raifed the dry air many degrees in tem-
perature) together with the water, we fhall have a unit of fa-
turated air,

Further, if we would raife the temperature of the latter
10, 20, or 200 degrees, and {till preferve the faturation, we
thall find it impoffible to proceed without an expenfe of power
adequate to the rate of folution, befides that proportion which
is employed in raifing the temperature throngh thofe fuccef-
five intervals of the {cale which are taken as the ftandard of
folution,

Now, in the cafe of equably advancing folution, if, as often
as the thermometer has rifen 10°, a quantity of caloric equal
to 100° has been imperceptibly fupplied in addition, this is
of no importance in the iffue, fince the temperature is flill a
true proportionate meafure of the power of folution in the ex-
tremes and in the mean: but in thofe of accelerated and re-
tarded folution it is otherwife; for here the very terms of the
propofition require that, as we advance in-the fcale, each de-
gree of temperature may anfwer to 10, 12, 16, 24, of folution,
or inverfely, and confequently to fimilar proportions of added
power. Now if in each unit fucceflively faturated at different
degrees there enters the duc proportion of power which it
needs mutt, then in every mixture that can be made of them
the total power of folution as well as the whole quantity of
water will be prefent, and there will be neither fuper- nor
under-faturation let the temperature refulting from the mix~
ture be what it may *.

Admitting, therefore, that caloric, or the caufe of tempera-
ture, is alfo a neceflary conftituent part of aqueous vapour in
whatfoever way it be ‘raed, and that the does of capa-
cities is well founded, we muft reject the theory of Dr. Hut-
ton altogether.

P.S. Whether the phrafe of “ the diffolving’ power of air
on water” was connected in the mind of Dr. Hutton with

* The remiinder of the paper, as read before the fociety, is fupprefled
by defire of the author, who has communicated what follows in its place,
aud in which his reafons for this will appear, —Epirox.

the

62 Confiderations on Dr. Hutton’s Theory of Rain.

the idea of fome other power operating jointly with the heat,
fuch as an attraction between the bafe of air and water, I am
not qualified to determine; but were it fo, this would in no-
wife affect the previous reafoning, as the conclufion refts en-
tirely on the temperature, 2. e. in the dogtor’s view, the ca-
lorie prefent, though they are in fact two diftinét confidera-
tions which he has blended.

In the concluding part of this effay, as it was originally
written, I had difeuffed the fubject of the folution of water
in air, and the feveral modes of its precipitation, on chemical
principles; regarding moift air as a ternary compound of
bafe of air, water, and caloric, formed and fubfifting by
chemical attractions, and decompofed by the operation of
the fame. “

Having fince perufed the excellent work of my friend John
Dalton *, which I have before: alluded to, and having feen
and repeated fome of the principal experiments therein de-
tailed, I muft acknowledge that, although I might plead the
authority of a Kirwan ¢ in fupport of the chemical theory of
evaporation, I am now difpofed to give up the idea of a proper
Solution of water in air in toto.

It appears to me that nothing need be more clear, fimple,
and conclufive, than the experiments and deduétions by which
the author attempts to prove that the evaporation of water
and feveral other liquids is a procefs uniformly regulated by
their temperature, the effect of the latter in equal furfaces
being the fame im vacuo and under the full preffure of the at-
mofphere ; the prefence of which has no other influence than
by its motion to multiply the furface of the liquid and carry
away the vapour produced ; whence the difference of quantity
evaporated in equal times in a moving and a ftagnant atmo-
fphere. The folvent power of ,air on water may alfo, there-
fore, be fafely claffed among thofe caufes which are not need-
ful to the efle&t in queftion, and therefore not to be retained
in philofophical reafoning.

* Experimental Effays on the Conftitution of mixed Gafes; on the
Force of Steam or Vapour from Water and other Liquids in different
Temperatures, both in a Torricellian Vacuum and in Air; on Evapora-
tion ; and on the Expanfion of Gafes by Heat.—Manchefier Memoirs, vol. v.

art 2. 1801.
: + Of the Variations of the Atmofphere, inferted in the Irifth Tranfac-
tons 1801.

XI, General

ane
°

£263,"

XI. General Confiderations on Vegetable. Extrads. By
C. PARMENTIER.

[Concluded from p. 386 of our laft Volume. ]
Juices of Plants.

To prepare thefe juices, they recommend, to colle& the
plants when they are in full vegetation, to clean,them care-
fully, to pound them in a marble mortar, 1o prefs them in-
clofed in a hair bag, after haying added to them a little water,
but only when they are either.a little too aqueous or too mu-
cilaginous. rhe ,

All the fap-veffels of the plant, or others, are broken by
the action of the peftle ; all the liquids which they contained
flow off, together with the green fecula and the attenuated
remains of the vegetable. dvi

They recommend to purify the juices either, by reft, or by
the heat of boiling water, or by means of the white of an
egg, or by making them pafs through gray paper.

The firit method is fit for the juices of fruits,

The fecond may be employed for all the juices of herbs
deftined to make extraéts. 5,

The third may be employed for all juices, infufions, or
decoétions, that do not contain tannin,

The fourth is neceflary for) all juices the virtues of which
exift chiefly in the volatile principles.

It is preferred in pharmacy for magitterial.juices, whether
they be volatile or not; the two vifcous juices excepted.

Maceration—Infufion—Decoétion.

Tn maceration, the cold water is attraéted by the dry vege-
table fubftances : it introduces itfelf into them, {wells them
up, and renders fluid whatever is foluble.

It has been found that maceration is fufficient to obtain
from quaffia, and even quinquina, the real active parts con-
tained in them.

In infufion, caloric more abundant than in maceration
renders the water more penetrating, more active, and more
folvent; it becomes charged with a much greater number
of the principles of the vegetable. .The preparers of medi-
cines make uke of it in preference for dry herbs and for leaves,
which, like fenna, for example, cannot bear ebullition with-
out lofing their virtues.

In decoétion, the water faturated with caloric acquires a
much greater energy; it penetrates in a more intimate man-

ner

64. Confiderations on Vegetable Extradls.

ner the vegetable fubjeCted to its action; it forces to become
foluble the fubftanices which were not fo at a lower tempera~
ture; it melts and feparates thofe whieh are oily or refinous ;
it diffipates thofe which are volatile; and feveral of them it
combines or decompofes.

They expofe to the action of boiling water thofe plants or
parts of plants only which are exceedingly hard, and in which
there exifts nothing volatile; and they often fubject thefe
fubftances to maceration and infution before they expofe them:
to ebullition.

In evaporation, the water charged with the folable prin-
eiples of the vegetables gradually abandons them to unite
with caloric, and to form with ita volatile fluid known under
the name of vapour: by thefe means, the principles before
diluted become concentrated, and aflume confiftence, the

ate and name of extracts.

They prefcribe a gentle fire for the evaporation of the
juices, macerations, arid infafions, and a ftronger fire for de-
coctions, taking care to choofe large and thallow evaporating
veffels, and to ftir the liquors to facilitate the evaporation of
the water, and to prevent the extraét from being burnt.

And to prevent that alteration of which the principles of
vegetables, when highly diluted with water and expofed to
the heat of an evaporation too long continued, are fufcepti-
ble, they recommend to employ only the neceflary quantity
of water, paying attention to the folidity of the fubftances
expofed to maceration, infufion, and decoction. They take
care alfo to employ for all their operations very pure water,
fenfible that it is only when it is in this ftate that it is fit
for boiling pulfe.

During the evaporation of feveral juices or decoctions, fome
phanomena occurred which did not efcape their notice.

They remarked, when preparing feveral extraéts which
they called faponaceous, that liquors became turbid; that
their furface was covered with a pellicle which feparated into
flakes, were precipitated, and formed: incruftations fufcepti-
ble of being burnt at the bottom of the evaporating veflels.

It was Baumé in particular who paid attention to thefe
precipitates; he fays they were faline.

The preparers of fuch medicines have alfo found that,
duting the cooling of the decodtions of roots or barks abun-
dant in refinous matter, and during the evaporation of feveral
of thefe decoétions, precipitates more or lefs abundant were ~
formed, which, according to the opinion of Baumé, were
owing to the refin, more or lefs altered, of the vegetables

employed.
a Thefe

Confiderations on Vegetable Extraéts. 63

Thefe precipitates, fome of which were thought by Baumé
to be faline and others refinous, have been confidered by Pel-
letier as earthy fubftances, and are afcribed by the modern
chemifts to the union which feveral of the immediate prin-
ciples of vegetables contained in the juices have formed with
exygen, which makes them lofe their folubility in water. _

C. Defchamps junior, apothecary at Lyons, is of opinion
that they are a mixture of lime, extractive matter, oily or re-
finous fubftances in-fome, and an aftringent refinous fub-
ftance in others; fometimes of a little calcareous falt, and
fometimes of a little filex or alumine.

As the obfervations and experiments on which he founds
his opinion may, by laying afide what he thinks unfavoura-
ble to oxygen, be exceedingly ufeful in the preparation of
extracts, we refer to his memoir publithed in the Annales de
Chimie for the year 7.

It refults, from the moft effential fa&ts annuunced in the
memoir of C. Defchamps :

1ft. That there exifts, in the vegetable juices or decoétions
which he fubjeéted to examination, a neutral falt, the bafe
of which has always been found to be lime, fometimes mixed
with a little filex and alumine, and of which the acid is often
different.

2d. That this faline combination, not very energetic of
itfelf, is weakened when diluted with water, and is eafily de-
ftroyed by ebullition, like many others, when the acid in it
is not in excefs, while it maintains itfelf, and is not altered
when the acid is fuperabundant in it.

3d. That the decompofition of this falt, when it takes
place, is only momentary, fince the depofits become rediffolved
towards the end of the evaporation by the fame acid which
has abandoned them; and which then, notwithftanding the
lofs it has fuftained in its quantity, refumes fufficient force to
re-eftablifh things nearly in their firlt ftate.

Hence arifes the neceffity of not feparating depofits which
prevent acids from being acid and deliquefcent.

4th. That thefe depofits, the major part of which is lime,
which carries with it, mrore or lefs combined, fometimes an
oily extractive, fometimes a refino-aftringent fubflance, and
fometimes a little effential falt, itfelf not being decompofed,
do not take place when the juices are not diluted with water,
when maceration and infufion are fubftituted for ebullition,
and when the evaporation is effected in a gentle heat. ;

By uniting the facts contained in the memoir of C. Des-
champs with the obfervations of the chemifts above men.

Vou, XLV, No. 53. L tioned,

;

*

66. Confiderations on Vegetable Ewtra&s.

tioned, we may fee how extras: mult be prepared i gerre-
ral: but there is one which requires, peculiar procefles that
muft be made known. ina 26 9ttol

1ft, Robs of the elder and buekthora are-made with juices
which have been extraéted 24, hours befote from. thé berries
of thefe two fhrubs, NIRVLO

_ During that time; thefe juices become charged with the
extractive colouring part lodged under the fkin.of the berries,
and by thefe means acquire more virtue. raed
ad. Extract of juniper is. obtained by maceration of frefl

juniper berries which have been. bruifed. ‘They, are evapo-
rated in a gentle heat, after being .madé to: pafs through
flannel.

It'is faccharine and aromatic: it would be acrid and re-
finous, if ebullition were employed, Baumé, however, has
preferibed it; but he made it light, and recommeénded not to
bruife the berries. ;

3d. Extracts of caffia and tamarinds are all products of the
maceration and pulp of thefe fruits. ’

Infufion. of tamarinds, cold, is attended with the inconve~
“nience of fuffering their effential falt to be precipitated during
the evaporation. .

4th. Extract of the corn poppy is produced’ by carefully
infufing the dried flowers,

5th. That obtained from faffron is very abundant; almoft
the whole of its ftamina are converted into extract; fo that
it may be confidered: as ufelefs to fubject them to this pre~

paration, which, altering their virtue a little, does not re-
duce them: to a lefs volume. :
6th. The extrad& of coloquintida is made with a decogtion.
of the pulp of that fruit freed from the feeds. To render it
fweeter, and make it lefs fufceptible of griping the bowels,
it ought to be deprived of its refin.
Baumé caufed it to be rediffolved in cold water. He fil-
trated the liquor, and the refin remamed on the paper. This
operation he repeated three times. ;
7th. Opium is brought tous from Turkey. The practice
of making it near the ruins-of Thebes has been loft. The
inhabitants of Egypt fill cultivate the plant which furnifhes
it; but. only to eat the feeds, which they are fond ef, as well
as of all other emulfive feeds, 40
Opium is an extract prepared. from the expreffed juice of
the leaves, flems, and heads of the white poppy.
That ufed in commerce is. very impure. The preparer of

opium diffolves it in water, makes. the liquor pais through

flannel,.

i i,

Confiderations on Vegetable Extrads. 67

flannel, and evaporates it in a balneum marie. When he
wifhes to make it more tranquillizing than-narcotic, he fub-
jects it to both the following preparations : 4:

The firft confifts in cutting the oprum into flices, boiling
it in the quantity of water neceffary to diffolve every thing
foluble it contains, ftraining the liquor, evaporating it to 4
half, putting it into a tin cucurbit immerfed in a fand bath
over a fire maintained three months night and day, adding
water in proportion as it is evaporated, {eraping from time to
time the bottom of the evaporating veflel, to prevent the refin
which is precipitated from being burnt, ftraining the hquor
when three months are elapfed, and then evaporating.

A folid extract, called opium, is obtained by long digef-
tion of all the extraéts of opium: this is the one moft
efteemed by Baumé. The fecond procefs is that employed
by Joffe to extra&t the gluten from the farina of wheat.

The opium is expofed under the cock of a veffel which
produces only a’ fmall ftream of water, where it is kneaded :
its extractive matter is diflolved, and the refinous part re-
mains in the hands; the liquor is then filtrated, and it is
evaporated to the confiftence of extsact.

The third method of correéting opium is that recom-
mended by Baumé for freeing the extract of coloquintida
from the prejudicial refin which it contains, viz. folution,
cold filtration, and evaporation. But as the refin of opium
is more dificult to be removed than that of coloquintida,
thefe three operations are repeated fix times fucceffively.

_ 8th. It is cuftomary to purify by folation and filtration ex-
tracts of the acacia, hypociftis, cachou, and liquorice, fold
in the fhops. But an exaét pharmacopolift will prefer pre-
paring the laft-mentioned article himfelf from the liquorice
of our gardens: he will treat it by infufion, and will thus
obtain a brown extract of a fweet tafie and very agreeable,
while the other is black and acrid, and often contains char-
coal and always copper, both taken from the bottom of the
bafon by feraping it with an iron fpatula.

gth. Extra& of fenna ought to be made from an infufion
of the leaves: ftrong decoction would add to the extractive
fubftance given by infufion, a mucilaginous matter which
would deka its virtue,

1oth. Extraéts of hemlock, ftramoniam, hyofcyamns, and
bella-dona, were prepared by Storck from the unpurified
juices of thefe plants.

{t is much better to evaporate thefe juices after they have
been purified and mixed at the end of the baking, the green
fecula being feparated. :

Ea . ' rith,

68 Confiderations on Vegetable Extraés.
11th. The dry extraéts of La Garaye are al] made by fimple

maceration evaporated in a balneum maria, or in a ftove, on
flat difhes; they form very thin {cales.

La Garaye filtered his liquors a fecond time when. they
were half evaporated; but this fecond filtration is ufelefs if
there exifts no depofit, and it is hurtful if there be one; be-
eaufe in feparating it, inftead of fuffering it to be rediffolved,
the extract acquires the property of attracting moiflure more
ftrongly.

The procefs employed by La Garaye for preparing his ex-
tracts alters as little as poffible the fubftances they contain.

rath. Extracts made from fuch frefh-gathered roots as
contain mucous bodies in {tates of folution and of infolu-
bility, that is to fay, mucilage, properly called ftarch, alfo
have need, as already faid, of a prelimimary preparation. to
make them lofe the latter fubftance, capable of becoming
mouldy when by the aid of warm water it has affumed the
fiate of jelly.

But this flarch does not hurt extraéts prepared with infu-
fions or decogtions of the fame roots dried, becaufe the mu-
cilage of the roots is de(troyed or modified by the deficcation,

13th. Several pharmacopolifis having obferved this change
which deficcation produces in the fiate of the mucous part
of plants, have thought that it would be of advantage to
prepare extracts from dried plants, efpecially in regard to
plants highly mucilaginous, fuch as burrage.

Experience has taught them that extraéts more abundant,
and which keep longer without alteration, may be obtained
by this method. .

Is the extractive principle increafed by deficcation at the
expenfe of the mucilage, or does the mucilage by drying in
the plants aflume a ftate which approaches very near to that
of extractive matter?

i4th. There are fome extracts in which it is neceffary to
setain a refino-gummy or extraéto-refinous fubftance: this
may be effected by fucceffively treating the plant which con-
tains it with water and with alcohol. The refult of thefe
two folutions, intimately mixed and properly concentrated,
gives this kind of extract.

15th. Sometimes wine is employed in order to have only
one infufion to make, and to fulfil the fame indication ; but
it is probable that the end propofed in this cafe is not ob-
tained.

Wine, indeed, befides its not diffolving fo well the two
required principles, is attended with the inconvenience of
furnifhing not only the extractive fubftance proper to it, ut

alfa

Defeription of a Three-blafi Fufing Furnace. 69

‘alfo an acid, which muft neceffarily have a greater or lefs ac-
tion on the extraétive matter of the vegetables, change its
nature, and increafe in the extraéts the tendency they have
to deliquefcence.

16th. Vinegar extracts very badly the principles of vege-
tables ; it generally alters them, or is altered by them.

- It may however be ftill employed as a folvent in regard to
fquills, garlic, refinous-gums, and as a vehicle of the odours
and colours of fome flowers.

17th. Extracts by highly rectified alcohol are refins; by
weak alcohol they are refins mixed with gummy or extractive
fubftances.

Vegetable fubftances fubjected to the action of alcohol are
dry, and much divided: this aétion is affifted by a degree of
heat more or lefs confiderable. The veffel in which the ope-
ration is performed muft be fufficiently large to allow the
vapours to circulate.

When the felution has been made and filtered, water is
poured over it, and the alcohol abandons the reffn to unite
with the water; or it is fubjected to diftillation, and the
alcohol paffes eff in vapours, leaving the refin free in the
fame manner.

18th. Ifjalap, for example, has been employed, to obtain
the refin, and if it be intended to procure the gummy ex-
tract of this root, the exhaufted refiduum of the refin muft
be treated with water, after which the infufion is filtered and
evaporated. -
~ It refults from thefe general confiderations on vegeta-
ble extraéts, that the pharmacopolift, if he proceeds me-
thodically, will always have the fatisfaction of furnifhing the
healing art with medicines containing the whole of the im-
mediate products of vegetables, and confequently fufceptible
of producing the effets which effentially belong to them,

——— See

XII. Defeription of a Three-blaft Fufing Furnace, conflruéted
in the Chemical Laboratory of the French School of: Mines.
_ By P. Tornevir-Narel, attached to the Council of
Mines.

"Tuts furnace is deftined for fufing different mineral
fubftances, in order to afcertain the nature of thems; and the
experience of fix years has fhown that it anfwers the intended
urpofe, By its means a very intenfe heat is, obtained, and
it was employed by C. Clouet for repeating his experiments
; on

50 Defeription of a Three-blaft Fufing Furnace.

on the converfion of forged iron into caft fleel, which were
attended with full fuccefs. i

Chemifts who have feen this furnace feemed defirous. of
being better acquainted with the confiru@ion of it: the
council even tranfmitted drawings of it to feveral perfons ;
and what has hitherto prevented a defcription of it froma
being given was a defire to afcertain its power by longer ufe.

L jong ago conceiyed the idea of a fufing furnace, in which
the wind was diftributed in three tuyeres placed in its cin-
cumference, and at equal diftances from each other; but I
had no opportunity of realizing this idea till I became. at-
tached to the council of mines.

Nearly feven years ago a plan was in agitation for con-
ftruéting in the laboratory of the fchool a fufing furnace
capable of producing a very great degree of heat, inorder to
operate with facility and {peed on larger quantities of mineral,
and confequently to obtain more precifion in the trials which
might be made than had been obtained by the imall furnaces
before employed for docimaftic experiments,

I propoted my ideas: they were approved by the couneil
of mines; and I was ordered to caufe the furnace 1 am
about to deferibe to be conftru@ed. The principal difference
between it and thofe before ufed for the fame purpofe, is,
that im the prefent one the wind is introduced through three
tuyeres, placed at equal diftances from each other im its cir+
cumference, whereas in common furnaces it enters only by
one.

This furnace is round, both outfide and infide, and con-
ftructed of very. refractory bricks, fecured by iron hoops in
fuch a manner that they cannot be difplaced. It refts on a
Square bafe of ftrong mafon-work, raifed to a fufficient height
abave the ground to render it eafy to manage.

The bellows are four feet in length, and the mean breadth
of them is about 20 or 21 inches: they are of wood, and
the joints are covered with white leather. The upper part
confifis of five folds and two half folds; the inferior, of two
folds and two half folds; They are placed 8 or 9 feet*
above a wooden box, the joints of which are covered with
leather, and into which the wind as it comes from the bel-
lows is conveyed by a copper pipe, three inches in diameter,

adjufted to the upper part of the box. The box itfelf is fup-

ported by two iron bars built into the wail. From the lower
part of this box defcend, in a vertical direction, three pipes

* This height is arbitrary; it depends in part on the manner in which

the bellows are difpofed, and on the height of the chamber in which the

furnace is placed,

of

ee

Defeription of a Three-blaft Fufing Furnace. = 98

of copper; two inches! in'diameter, bent at right angles
about 45 inches below it, to bring them ‘into’ a horizontal
pofition, and to convey the: wind to’ the furnace, which is
about fix feet diftant.~ Phe extremities of thefe pipes are
fitted into three tuveres of forged iron, fixed at equal diftances
around the circumfrence of the farnacet thele three pipes
are: more'or lefs curved or hent, ‘to convey the wind into the
furnace by the three apertures made for that purpofe.

About fix inches below the box is adjufted, on each of the
three’ tubesy which! defeend in’ a vertical direGion, a brafs
cock about ‘three inches of interior diameter: thefe cocks
ferve to intercept entirely the communication between the
bellows and the farnace 3 and by opening them all more or
lefs, or each of them feparately, any required quantity of
wind may ‘he'obtained *.2
--Thefe cocks are well ‘fixed to the tubes, and kept in their
placé by two clips of iron fuited to the diamtters of the
tubes, and forming a kind of three coliars, which by means
of four ferews embrace’ and confine them: thefe pie es of
jron are themfelves made faft to two crutches of tron, which
fupport the box and are fixed to it by ferews.. ‘Phe box is
kept on the crutch®s by two ftraps, which embrace it at each
extremity, and are fixed by female ferews, which are fitted to
ferews'on the ends of ‘thefe traps after they have pafled
through the horizontal part of the two crutches.

To give the proper ftrength to this farnace, a folid fquare
was conftructed of mafon-work, about a foot larger on cach
fide than the exterior diameter of the fides of the furnace,
which were from 21 to 22 inches from outfide to outfide.
Bricks were placed on the ground in the middle of this erec-
tion for the extent of 18 inches, in order to form a bottom,
and on this bafe were placed the fides of the furnace con-
firuéted in the manner about to be deferibed.

T caufed to be forged two iron hoops fix tines in thicknefs,
from 2 to 2" inches in bréadth, and about 22 inches of ex-
terior diameter: thefe ‘two circles were faftened together by
three bars of iron, the diftance of their exterior edge being

* Care muft be taken, when. the, aétion of the bellows ceafes, to fhut the
gocks, efpecially hen coals are yfed in the furnace; for the hydrogen dif-
i“ ape that mineral fabftance afcends into the box and, when the
bellows are again made to adb nay inflame, and caufe a violet explofion,
or even byrit the! bellows. « Thissacadent once took place iin the furnace
here deferibed: the box burt with a loud nove on the lint, ftroke of the
bellows, che pay which filled them having fudeenly inflamed ; but by
‘good fortiine no perfor was Hurt. The fame thing happened at the houfe
wif C. Gorlier, lock(mith, of Paris : one of “his bellows Burtt with a hornd
explofionabithe moment ayhen théy) were puttiaimotions | ;

E4 2 kept

9% Defeription of a Three-blaft Fufing Furnace.

kept at about nine. inches, the height of :the bricks: thefe
bars are pierced with holes towards the end riveted om the
circles; and placed at equal diftances on their circumference.
One of the extremes of each of thefe three bars. is: left of a
fufficient length to-pafs beyond the lower circle about an
inch, in order to make them enter into three holes formed in
the brick- work which forms the bottom of the farnace, and
by thefe means: to prevent the furnace from becoming de-
ranged. od A

This kind of iron frame was filled with bricks fimilar: to
thofe employed for the bottom? of the furnace: they were
rubbed one on the other to fmooth them, and. the corners
were a little rounded; fo that, being placed upright with their
broad fides applied to the iron hoops,, the narrow fide ftood
inwards. By thefe means all thefe bricks were adjufted: in
fuch.a manner as to touch each other by their broadeft faces,
and to form’the fides of the furnace, the thicknefs of which
was equal to the breadth of the bricks, and its depth to their
Jength. Three apertures were referved for the tuyeres, which
terminate the three tubes that convey the wind, by cutting
ate as many bricks a portion equal to the thicknefs of a

rick,

Thefe bricks thus adjufted were taken from the iron frame,
and then replaced, putting between them a cement to con-
nect them firmly and to fill up the joints. The duft. pro-
duced by cutting the bricks was referved for this purpofe ;
and | defired the workman to mix with it a fmall quantity, of
clay diluted ina great deal of water, in order to make a puddle
for daubing over the bricks, and in particular to put between
them no more than was neceffary for filling the joints and
the fmall fpace left between their faces in confequence of
any inequality left in dreffing them.

The furnace thus conftrnéted was then placed on its bafe,
a ftratum of the fame mortar employed for filling up the
joinings of the bricks being firft interpofed. The extremities
of the three iron bars projecting beyond the lower circle were
placed in the holes Jeft in the bafe to receive them. The
body of the furnace encircled with iron, both by its weight
and the gentle blows given to the iron hoops above the bars
which conneéted them, expelled the excefs of the mortar, and
caufed a part of it to enter and unite with that which filled
up the joints of the brick-work of the circumference, which
rendered it immoveable,

The bellows is fecured as ufual by crutches of iron and
fupporters fixed in the wall and.to the floor: the handle is
difpofed in fuch a manner, that,the rope which makes it aé&

- atta | may

Defcription of a Three-blaf? Fujing Furnace. 73

may be pulled by the fame perfon who -manages, the fire.of
the furnace, which in certain cafes is neceffary.

The tuyeres of forged iron which) receive the ends of the
copper tubes are fecured in their proper apertures.in the cir-
cumference of the furnace by. pieces of brick and mortar
fimilar to that employed for filling up the joints; and the
ends of the copper pipes introduced into thefe.tuyeres are
luted with the fame mortar, a little thickened with brick-duft.

The aperture of thefe. tuyeres towards the interior of the
furnace is only nine lines in diameter ; on which, account, as
the volume of air furnifhed by the bellows cannot. pafs fo
quick as it is produced, it becomes: condenfed in the box
placed above the cocks. By thefe means a very uniform blaft
1s obtained, which can alfo be regulated by opening more or
fewer of the cocks.

During more than fix years, fince this furnace was con+
ftrugted, it has fuffered no derangement: it is not even
cracked. It is however worn in the infide by the violence of
the heat it has experienced, which has increafed its diameter
about two inches. The parts round the. three tuyeres have
alfo got hollowed, fothat it has need of being repairedi, It
is intended to make it deeper, and to have a kind of moye-
able muffs or linings made-of fire-clay, in order that its dia-
meter may be reduced at pleafure® it is.meant alfo to con-
ftruét it in fuch a manner, as to depofit the reft or fupport for
the crucible, not on the bottom of the furnace, but on bars
of forged iron placed at the diftance of fome inches from that
bottom, fo as to leave below them/a yacuity.in which the
blall of the bellows may be diffufed, and from which it may
rife, pafling between the bars to traverfe the mafs of charcoal
which furrounds the crucible. The blaft will then produce a
more uniform fire, and the fame can no longegbe directed
again{t the fides of the crucibles; fo that the rifk of their
breaking by fudden inequalities in the heat will be much lefs.

This alteration is going to be immediately carried into ex-
ecution, and the method propofed for doing it is as follows :

A round frame will be made of forged: iron, in which
bricks will be placed in the fame manner as above defcribed.
In the lower part of the, furnace )an aperture will be referyed
for raking out the athes, which will be clofed by means of
a door of baked earth carefully luted with clay.. Some inches
above the bottom of the furnace will be placed a grate of
forged iron, and between this grate and the bottom of the
furnace the \tuyeres will terminate, and, the blaft be intro-
duced, Muffs or linings of ‘very refractory, earth, will *

€

we Dejeripiion of a Three-blaft Fufing Furnace.

be introduced; f6:as to defeend tothis grate.” There w ‘ite he
two of them, : one within the other, ‘and both within the
body of ‘the furnace. Aethe lower part thefe muffs will be
farnithed ‘with’ a’ xin, projecting outward fo as to ‘leave be-
tween the body'of the furnace and the muffs a vacuity, which
will obé Inted'-at “the bottom with clay; and whieh’ with: be
filled svith pounded pet or any ‘other fubitance a ee cone
duétor of heat.” 0"
: The'dnterior ‘muy or bork e chien) may: be rafnnbll at
leafure to obtain a! furtaesttt ereatér or dels capaeity aeeord-
ing to the operations to be performed: Ttis propofed’' to apeee
the mufls wider at the top‘thanat the bottorit a }

vo dixplanation. of the Figures (Plate lL). d oN

Fig. 1. Plan of the bellows and of the furnaces: AB; the

bellows made of wood, the folds of which are alfo” of Wood
covered with Jeather on the joints. CD, the handle w hich
_ ferves for moving the bellows. E,a copper tube which con-
veys the wind of | the bellows into the box FG, in which it is
eondenfed. FG, a box of wood ferving as a xelerw oir for the
wind condenfed | by the bellows. H1, KL, MN, three pipes
adapted to the box FG, and which convey the atid into the
infide of the furnace by three tuyeres, I, L, N. OP, mafon-
work to fupport the horizontal pipes. Q, the furnace pro-
perly fo called, the form of which is diveuiat; and which i is
placed on the fquare mafon-work R,S,T, U.
Fig. 2. Elevation of the furnace, ' the pipes which convey
the blaft, the cocks, the condenfing box, and the bellows,
AB, the bellows mounted in’ theit ‘place, and fupported by
the iron-work neceffary for fecuring it, which is fixed in the
wall and to the floor. CD, the handle which ferves for
moving theybellows. E, the copper pipe which conveys the
blaft of the bellows to the box FG in which it is condenfed,
At G is a hole fhut by a large cork flopper, which can be
opened at pleafure. This box is fupported by two. crutches
of iron f, g, and 4,2, built into the wall, and on'which it is
fixed by two iron ftirrups 4, 7, |

Fig. 3. One of the crutches'and its ftirrup are feen repre-
fented fidewife at f, 9, 7; ‘the extremities, 7; 0, are built into
the wall; and the two ends, ps'gy of the iron ‘piece which
keeps’ the box on the horizontal traverfe of the crutch, are
tapped; and: receive ferews which make them faft to the
eruteh: fe. HY, KL, MN; ‘are ‘three pipes which con-
vey the flisdt into the interior of the furnace.’ 'Q,R,8,T,U,
melodie on which is placed ‘the furnace Qy: and whieh

ferves

Defeription of a Three-blaft Fufing Furnace. "5

ferves it as-a bottom. OP, mafonry which ferves to fupport
the three pipes that convey the wind to the furnace. AY Z,
fig, 2. are the three cocks fixed to the three pipes which pro-
‘ceed from the box to convey. the wind to the furnace.

In fig. 4., the dimenfions of which are double thofe of
fig. 2., may be feen the details of one of thefe cocks.

At ayspt, the body of the cock, is feen in front ; the ftopper
bemg taken qut fhows at rand at ¢ the two holes which re-
ceive the tubes.that communicate either with the box op with
the tuyeres. « exhibits the body of the cock feen on. oge fide ;
wv the key with its aperture , and its head y, This key,
turned round more or els in its focket, ferves to. give. more
or Jefs wind. 1,2, 3, iron clips which fecure the cocks at
the diftance they ought to be from each other,, and connect
them at the fame time to the iron cruiches which fupport
the air-box. R
_. Fig. 5. a plan of thefe two clips. They are bent at the
places marked 1, 2, 3, ta embrace ihe body of the three cocks,
and fecure them in fuch a manner that they cannot be de-
ranged when they are opened or fhut.

Fig. 6 and 7 reprefent the plane and fection of the changes
and additions propofed to be made when the furnace is ren
conftruéted. At I,L, and N, are feen the extremities of the
three pipes that enter the forged iron tuyeres, and convey the
wind to the interior of the furnace, a, 6, and c, indicate the
thicknefs at the upper part of each of the mufis and of the
hody of the furnace, between which there are two vacuities
filled with pounded glafs or fome other bad conductor of heat.
d, the grate on Lith are depofited the refts of baked earth
defined ,to receive the crucibles, ¢, the crucible, lyted and
attached with clay to a relt of baked earth, athe

Note by the Author on the Furnaces which bave feveral »
f , Tuyeres.

The advantage arifing in. large founderies from the appli-
cation of two or three tuyeres inftead of one, is well known ;
but I do, not believe that fuch an arrangement was ever
adopted in {mall furnaces, a,

_ At Treibach, in Carinthia, C. Le Febre, and Haffenfratz
member of the council and infpector of mines, faw, about
twenty years ago, a large furnace with two tuyeres; drawings
of which they brought to France, and which they repre-
fented in the third plate of 1? Art de fabriquer Jes Canons, by
Monge: two pairs of bellows fupply wind throu h two oppo-
fite tuyeres, and fince that arrangement ‘the daily product of

metal has been doubles
| In

075 = “Metallic Solution which forms a Yellow Ink.

In England, Mr. Wilkinfon has employed feveral years,
for fufing iron ore by coke, furnaces of lefs height than thofe
which he ufed before, and he fupplies wind by three tuyeres

_ placed at equal diftances in the circumference of the furnace.

XII. On a metallic Solution, which forms a,Yellow Ink,
that appears and difappears like that of Hellot. Read
before the French National Infiitute, by C., GiLLET-
Laumont, Affociate*. |

Some time ago, having thrown into the fire a folution of
a mixture of fulphate of copper and muriate of ammonia,
where it produced very agreeable colours, fome of it fell upon
a piece of paper placed in the chimney, which became of
a bright yellow colour. Having taken the paper from the
chimney, I was much aftoniflied, fome moments ‘after, to
find that it was no longer coloured: on again expofing it to
heat the colour reappeared, and difappeared in like manner
on cooling.

I tried lately to repeat this experiment; and I obtained
from thefe two falts, mixed nearly in equal parts, a folution
of a bright yellow colour when warm, and of a beautiful
emerald green when cold, which at firft gave cryftals in
oblique prifms with rhomboidal bafes, and then blue cryftals
in flat oétaedra.

This liquor and the folution of the cryftals gave a yellow
ink, which appeared yellow with heat, and difappeared with
cold, but ftill better with moifture.

I obferved' that thefe folutions are indebted for this pro-
perty only to the muriate of copper, which when employed
alone does not produce the fame effect.

On comparing this ink with that given by the muriate of
cobalt, known under the name of the fympathetic ink. of
Hellot, it is feen that all thefe kinds of ink are indebted for
the property which they have of difappearing, only to metallic
muriates, which powerfully attract the moifture of furround-
ing bodies. . : ;

The yellow ink produced by the muriate of copper and the
folutions which contain it (very different from thofe which,
being at firft invifible, remain fixed after they have appeared)
gives by-its colour a variety very diftin& from that of Hellot,
which 1s of a fea green : with the latter it forms varied tints
of an emerald green. ‘i

* From the Fournal des Mines, No, 58.

They

ES ae

Short View of the Craniognomic Syflem. ay

_ They may be made to appear at pleafure by the aid of
heat, and to difappear very {peedily by putting the writin
between ;the folds of paper fomewhat moift: but I mnt
here obferve, that it requires much care to make the experi-
ment fucceed completely, and that a certain degree of heat
muft not be exceeded ; otherwife, the paper being icorched,
the writing can no longer difappear.

XIV. A fhort View of the Craniognomic Sy/lem of Dr. GALL,
of Vienna, By L.Bosanus, M.D. Member of the Me-
dical Societies of Jena and Paris, and of the Society of the
Obfervers of Man*.

Ar all periods, a defire to find in the exterior of man cer-
tain marks. indicative of his interior faculties, his paflions,
his morals, &c., has induced the learned to eftablith fyftems
of phyfiognomy more or lefs:fatisfactory. The mott ftriking
of thefe fyftems are thofe of Baptifta Porta and Lavater, the
theory of the facial angle, and the fyftem of Dr. Gall.

In regard to the firft, who employed himfelf in comparing
the contours of the human figure with thole of beafts, ob-
fervers have determined its value, and confider his principles
as the fruit of a difordered imagination, as too bold, too little
founded on rational obfervation, and abfolutely uncertain in
its application. ms

The fyfiem of Lavater has had more fuccefs; but while we
revere the genius of that celebrated man, who was truly a ereat
obferver, we cannot help acknowledging the inftability of the
bafis on which all the opinions he advances reft; and the
mind is not fatisfied with truths which can be appreciated
only by an imagination equally exalted, and a touch fo deli-
cate as that of the author,

The theory of the facial angle, which embraces a wider
field than the fyftem of Lavater, leaves us in uncertainty re+
fpecting the detail of the faculties, and gives us only general
points of view; ‘but it prefents us with this truth, of the
greate(t importance—that the facial angle increafes in fize in
proportion to the faculties of animals: and in this it coincides

* From the Magazin Encyclopédigue, No.4, Meffidor, an. 10. Dre
Bojanus in a note fays: ** As this hiftorical explanation is by no means in-
tended to prove the truth of Dr. Gall’s'fyftem, it can lead to no decifive
opinion on this fyftem, which will be eftablifhed by its author on folid
reafoning and convincing teftimony. Tt is neceffary alfo (fiys hic) to ob-
ferve, that the paffages marked with inverted commas do not reft on the
authority of Dr. Gall,”

in

58 Short View of ihe Craniognomie Syftent
in/an évident manner with the general refults of the fyfietia
of Dr. Gall.

‘ Withowt entering into an éxaét detail of the laborious
route which this learned philofopher purfued, to be enabled
to eftablith a certain bafis in a ference hithertd hypothetical,
we fhall examine briefly his fundamental principles. _

1. The Brain is the material Organ of the internal Faculties.

Far from attempting to decide the metaphyfical queftions
on ‘the nature of the foul, or what may be fuppofed as the
occult caufe of the internal faculties, we are, however, forced
to admit a material organ for their action. "a

But, as it is obferved that thefe faculties are found only
where the brain exifts; that they are loft with it; that difeafe
and Jeefion of the brain have a fenitble influence on their de=
gree and their action; that the volume of the brain increafes
im direét proportion to the faculties of animals ; it is not’ven=
turing too far to confider the bram.as the material and inter-
mediate orgait. 14

[It might be here objected; that in feveral cafes individuals
have loft a confiderable portion of the fubftance of the brain
without the faculties being fenfibly diminithed ; but it is to
be obferved that the greater part of ‘the cerebral organs exift
double, and that the obfervations mentioned are not exact.]

“9. The Brain contains different Organs independent on each
© © other for ihe different Faculties *.

The internal faculties do not always exift in the fame pro
portion to each other. Thete are fome men who have a great
deal of genius without having a memory, who have courage
without circumfpection, and who pofiefs a metaphyfical {pirit
without being good obfervers.

Befides, the phenomena of dreaming, of fomnambulifm,
of delirium, &c. prove to us that the internal faculties do not
always act together; that there is often a very great activity
of one, while the reft are not fenfible.

Thus in old age, and fometimes in difeafe, fuch, for ex
ample, as madnels, feveral faculties are loft, while others
fubfilt: befides, a continued employment of the fame faculty
fenfibly diminifhes its energy: if we employ another, we
find it has all the foree of which it is fufceptible; and if we
teturn to the former faculty, it is obferved that it has refumed

* This idea of independence ought not to deftroy that principle of ani-
mal organifm, that all the parts are in a reciprecal ratio: it ought to mark
only, that the aclion of one organ does not abfolutely imply the fame de-
gree in another. ,
its

—

of Dew Gall of Viennass 79

its ufual vizour. It is thus that, when fatigued with reading;
an abftraét philofophical work, we proceed with pleafure to
aipoctical one, and then refame) with’ the fame attention our

ormer occupation, (fh }6 rastivb sd) os bypese i ato

_ All thefe phenomena prove that the faculties are diftinc

and independent of each other, and we are inclined to believe,
that the cafe is the fame with their material organs. i ydt

_ [We do not entirely agree with this idea of Dr. Gall, and
we believe, on the contrary, that, the feparation of the ma->
terial organs_ought),to be confidered as) the caufe 6f the di-

inétion of the internal fagulties.. It,appears, to, us/at leatt,
that by, fuppofing the faculties themfelves as originally fepa-
rated we cannot fave ourlelves-from falling into materialifm,,
which exifis when the mind is no longer confidered as unity.}

3: ‘The Expanfion of ike Organs contained in the Cranium is
““an'the direét' Ratio of the Piic2 of their corre/ponding Fa-
eulties. ' a quis

_ This principle, digtated by analogy, refts on this axiom,
t at throughout all nature’ the, faculties are always found to
be proportioned to their: relative organs ; and the truth of it
48 proved in a fpecial manner, by the particular obfervations
of Dr. Gall.) as Avia
_ _Itas however to be remarked, that exercife has a great in-
fluence.on the force,of ‘the faculties, and that an organ mo-
derately expanded, hut often exercifed, can give a faculty fu-
petior to) that which) accompanies a very extenfive organ
never put in action; as we {ee that a man of a weak con-
formation acquires, by continued exercife, ftrength fuperior
to another of a more athletic ftrudture. : ib
-» [We mufi bere mention an opinion which feems to refult
immediately from this principle, and which, however, is falles
it-is, thatthe volume of the brain, in general, is im the direct
ratio of the energy of its faculties, Obfervation has proved
to Dr. Gall, that we cannot judge of the firength of the facul-
tiess but by the development of the feparate organs which
form diftin& eminences in the cranium ; and that a cranium
perfe@lly round, of whatever fize it may be, is never a proof
of many or of great faculties.) | at
©) I do not recollect to have heard the reafon affigned by Dr,
Gall, but, in my opinion, thefe brains may be confidered as
in a ftate analogous to obefity ; and as we donot judge of the
mufcular force of a man or an animal by the volume of their
members, but by the development of the mut{cles in parti-
cular, I think we ought, in like manner, to judge of the
neg fifength

;

~ wie

80° Short View of the Cranisgnomic Syflem

ftrength of ‘the faculties by -the development of the relative
organs. OW

“In the lat place, the 4th principle, the moft important
for practice in regard to the fyftem of Dr. Gall, is:

We may judge of thefe different organs and of their facul-
ties by the exterior form of the cranium.

The truth of this principle is founded upon another, viz.
that the conformation of the cranium depends on that of the
brain; ‘a truth’ generally: acknowledged, and proved by the
anterior part'of the brain, by the impreffions in the anterior
part of the cranium, and by other facts.
~ [There are fkulls, it is true, in which an external protuberance
of the bone correfponds to an interior one; and this irregu-
larity, which is found fometimes as a difeafe, and: moft com-
monly at an advanced age, when the cerebral organs do not
oppote the fame refiftance to the cranium, .renders the prac-
tice of Dr. Gall’s fyflem, in fome meafure, uncertain.]

Guided by thefe principles, Dr. Gall examines the nature
of the fkull, compares the crania of animals and thofe of men
analogous and different in faculties. His refearches have
proved to him, in a manner almoft inconteftable, not only
the above truths, but that the faculties of animals are ana-
logous to thofe of man; that what we call inftinét in ani-
mals is found alfo in the latter, fuch as attachment, cunning,
circumfpection, courage, &c.; that the quantity of the or-
gans fixes the difference of the genus of animals, their re-
ciprocal proportion that of individuals; that the difpofition
originally given to each faculty by nature may be called forth
by exercife and favourable cireumftances, and fometimes by
difeafe, but that it never can be created in the cafe where it
has not been given by nature*; that the accumulation of
the organs takes place in a conftant manner from the hind
part forwards, from the bottom to the top, in fuch a manner,
that animals in proportion as they approach man in the quan-
tity of their faculties have the fuperior and anterior part of the
brain more expanded ; and, in the laft place, that in the moft

erfe&t animal, man, there are organs in the anterior and
Hpetir parts of the frontal bone, and of the parietals, deftined
for faculties which belong to them exclufively. ‘It is under
the latter point of view that the difcoveries of Dr. Gall agree

erfetly with the theory of the facial angle, which feems
fiill farther to eftablith the truth of them.”

In regard to the details of Dr. Gall’s fyftem, and the enu-
: '* The germ of every organ muft exift in embryo, if the expanfion of
that organ is to be afterwards called forth. ;

; mieration

|
|

of Dr. Gall, of Vienna. - 8x

meration of the different, organs which he found, it is diffi-
cult to give an exact and fatisfactory defcription of them,
when illuftrated with the number of facts and examples
which he employs to prove, in an evident manner, what he
advances; I fhall however attempt the enumeyation, being
perfuaded that it will contain feveral illuftrations of the au-
thor’s manner of confidering the fubje&t, and give a true
idea of thé method to be purfued to attain to-his refults *,

1. Organ of the Tenacity of Life,

The firft organ which the author thinks he has found is
that of the tenacity of life (tenacitas vite) : he confiders the
medulla oblongata as the feat of it; and as the circum-
ference of the large occipital foramen is in the direct ratio of
the extent of the medulla oblongata, he employs the fize of
this hole to judge of the intenfity of the life of an animal.

The obfervations which ferve to fupport this opinion are,
that this hole is generally larger in the crania of women
than thofe of men; that it is conftantly large in the cat, the
otter, the beaver, the badger, &c., animals well known to
have a yery tenacious life, Befides, there are no {peedier

means of killing an animal than to cut the medulla. ob-

longata. .
2. Organ of the Inflind of Self-prefervation.

A little further forward in the medulla oblongata, at the
place where it leaves the brain, the author places the organ

of the love of life, or of the inftinét of felf-prefervation,

As animals furnifh no inftances of fuicide, it was only,

from the human race he could procure examples in favour
of this pofition; and feveral cafes of fuicide, in which this
part of the brain was difeafed, determined him to confider it
as the organ of that faculty: he does not, however, confider
it as an abfolute truth; he waits for further examples to
ferve as proofs,

3- Organ for the Choice of Nouri/bment.

. The organs for the choice of nourifbment are found, accord-
ing to the author, in the quadrigemini tubercles; the ante-
rior of which are larger in carnivorous animals, the pofterior
more expanded in graminivorous, and which in omnivorous
are of equal fize.

4. Cerebral Organs of the external Sen/fes.
The middle part of the bafe of the brain is deftined to the

* Compare the different articles with the ¢orrefponding numbers in
the figure, P|. II.

Vot. XIV, No. 53. F external

3 i

8y Short V ivewvof the Cranit «namic Sy/lem

external fenjes; This is the region? from ‘which the tierves
diftributed to the organs of thefe fenfes proceed. 1 gD
i in. 5s, Lbe Organ of Inflin& and, Copulation,
_ The organ of inflinét: and copulation’is' fituated atithe bafe
of the occipital bone, behind the medulla oblongata and the
Jarge occipital foramen. ansbilates a e‘yords
This organ never expands but at the age of puberty; and
its increafe has.a great influence on the ae of the nape of
the neck, becaufe to this part of the cranium its mufcles_are
affixed. ggg aa va eas
In animals caftratéd before the age of puberty, the expan-
fion of this organ does not take place. “It is certain that the
Bull has the’ cheft much broader than the ox; and that
“ horfes fubjeéted to taftration before their cheft is full have
that part always flender.”’ ted 1
‘In the ape, the hare, and cock, this organ is very appa-
rent; and in pigeons and {parrows the occipital forms a par-
ticular bag, which feems to be an appendage of the head;
and it is well known that thefe animals are exceedingly ar-
dent in copulation. The fame difpofition is fometimes
found in the cranium of man; and Dr. ‘Gall has in ‘his col-
Ieétion the fkulls of feveral fools, who were diftinguifhed by
their lafeivioufnefs, and whofe occipital bone préfents an
enormous projection. tA
“6. Orzan of the reciprocal Love of Parents anil Children, *
(The organ of the reciprocal love of parents and children
occupies the whole pofterior,and fuperior part of the occipis
tal: by its pofition it is, intimately connected with the pre-
ceding organ, the action, of which. muft neceflamly haye. an
influence upon it....‘* Sometimes its, excefliye expanfion
contributes 40. produce that prolongation of the occipital iz
the form of a bag, mentioned in the preceding article.”
This organ in general is more ftriking in women than in
men, and throughout all nature moré fo'in the female than
ui the «male fex: it is very apparent, im ‘particular, among
apes, whofe love for their young is fo well knowm that ot has
become proverbial: . doidw le von
» “In general, all/animals, which fhow a great deal of: ats
tachment to their young are provided with it; andit appears
to us that pigeons, the male,and female of which both fit on
the eggs, and which feed their young by a fort of rumina-
fon, may be given as an example.”
. The cuckow, .which never rears, its.young, is almoft en-
tirely deftitute of this organ.

vA - 9. Organ

'?

of Dr. Gall, of Vienna. 83

>. Organ of Attachment and Friendfhip.

“At the pofierior and middle part of the parietals, and the
lateral part of the occipital, .is the organ of attachment or
_ friendfhip.._ , Pee 5 : es

© Its pofition brings it into intimate connection with, the
two preceding organs, and it appears that thefe organs have
an action together, -efpecially in animals deftined to live in
fociety.” Int
Does fhow the moft furprifing marks of attachment; ‘and
the inftances are furnifhed chiefly by the barbets, baffets,

nd houfe-dogs. Thefe fpecies, therefore, are diftinguifhed

ya large head, on which is found the expanfion of this or-
gan behind and above the zygoniatic apophyfis.. The greé
hound, which is the leaft fufceptible of attachment, has the
head narrower behind, and in general is deftitute of this
organe
8. Organ of Courage.

It is the pofterior and inferior angle of the parietal that
edrrefponds to the angle of courage. It contributes to en-
large the fize of the head, and-to feparate the ears from each
other. Its proximity to the three preceding organs explains
tous the fury of animals in rutting-time, and the excels of .
courage in thofe which have young, or which protect the
female and the individuals of their fociety.

- It is very ftriking in the hyena, the lion, the wolf, fome
fpecies of dogs, and particularly in the wild boar, the teme-
rity of which is well known.

On. the other hand, the afs, the gre-hound, the fheep, and
the hare, which are diftinguithed by their timidity, are en-
urely deftitute of this organ: their head is ftraight pofteriorly,
and their ears are very near to each other.

A very furprifing phenomenon feems to fupport the opi-
nion of Dr. Gall on the feat of this organ: it is a certain in-
voluntary’ motion of man when he lofes courage. He
fcratches behind his ears, as if defirous to excite the action of
the organ which gives him that faculty.

[We have remarked a mgyement in cats which appears to
have fome refemblance to the above, and which relates to the
organ of attachment. When fawning on man, they always
prefent the pofterior part of the head to rub it againtt him. |

g. Organ of the Inflin& to affaffinate.

Before the organ of courage, towards the middle of the la-
teral part of the parietals, refides the organ of the inftinét to
aflaffinate,

Fa It

84 Royal Academy of Sciences, Berlin.

Tt appears in all carnivorous animals which live on prey.
Dr. Gall found it in the crania of feyeral affaffins who had
been exccuted. J ,

su

t

10. Unknown Organs.

Two organs which correfpond to the temporal bone are as
yet unknown in regard to their funétions. ae
wit Syil « 11. Organ of Cupning..

The organ of cunning occupies the anterior and inferior
part of the parietals: it appears in all animals diftinguithed
by that faculty; fuch-as the fox, polecat, domeftic eat, the
diver *, and is in intimate connection with the organ of theft,
which conflitutes a prolongation of it towards the orbit,’and
which is found in the cat, fome dogs, and the magpie.

It is, perhaps, to the development of this organ that we
ought to afcribe the-great width in the heads of the Cal-
moucs, among whom a propenfity to thieving is a national
chara¢teriftic.

12. Organ of Circumfpeétion.

The organ of circum{peétion is found in the middle of the
parietals, above the organ of cunning and that of the inftin&
of affaffination, aes [

The exceflive development. of it’ produces irrefolution ;
want of it, ftupidity: it is very ftriking in the chamois goat;
and roe-buck, the. circumfpection of which is fingular, and
which never travel on an unknown road without great pre-
caution,

It is found alfo in animals which do not quit their habita-
tions but in the night-time, fuch as the ow}, otter, &c.

[To be continued. ]

XV. Proceedings of Learned Societies.
ROYAL ACADEMY OF SCIENCES, BERLIN.

Tu IS Academy has propofed the following as fubjeéts for

Prize Queffions: > ~ )
I. The Mathematical Clafs offers a triple prize for the beft
differtation on the obliquity of the ecliptic.

Papers on this fubject will be received till the 1ft of May
1806.

* One obfervation difficult to be arranged is, that Dr. Gall always
found this organ developed in poets : he gives no explanation, but his. ob-
fervation is correét.

II. The

Royal Academy of Sciences, Berlin: 85

If. The Clafs of the Belles Lettres has again propofed the
queftion re{fpecting the Goths and Gothicifin, with the follow-
ing variations and definitions, and offers a double prize. >

1ft. Did the northern tribes, the Goths, Vandals, Suevi,
Longobardi, Franks, Bureundians, Anglo-Saxons, &c., who
divided the weftern poffeffions among them, bring with them
from their own country any thing peculiar in their arts and
fciences? or, Cannot it be rather proved that every kind of
mental culture which thefe people acquired was obtained
from their intercourfe with the old inhabitants of the Roman
empire, and from their being mixed with them by their
conquetts ?

2d. Ought we therefore to afcribe to thefe people a peculiar
ftyle in their literature and arts? or, Are the fpecimens of
thefe arts which occur in the middle ages only modifications
of the antient Greek {tyle, produced after the decline of the
Roman empire by the new political, religious, and moral fitu-
ation of thefe people ?

3d. And, if the latter be the cafe, what are the diftineuith-
ing marks of the produétions of the middle ages in literature
and the fine arts? What is the proper order in which they
follow each other? What influence had the cultivation of
the fine arts among the Arabs on thofe of the wettern part
of Europe?” When and throngh what channels was this in-
fluence perceptible, and by what figns was it diftinguifhed ?
= Papers on this fubje& will be received till the 1it of May
1804.

IIT. The following is the queftion propofed by the Phyfical
Clafs :—Has electricity any influence on matters in a ftate of
fermentation? Does it contribute to, or impede, fermenta-
tion? Does it produce any change in the produéts of fer-
mentation? What advantage can be derived from calling
forth this matter in order to improve the art of preparing
wine, beer, vinegar, and brandy ?

Papers on this fubjeé will be received till the 1 of May
1803, |;

IV, The following is the queftion propofed by the Philo.
fophical Clafs :—Is the moral worth of an action to be taken
into. confideration in the application of a criminal law? And
if this be the cafe, how far can it be done?

aot on this fubjeét will be received till the 1ft of May
1803.

F 3 ACADEMY

86 Académy of the Ufeful Sciences, Erfurt, Sec.

ACADEMY OF THE USEFUL SCIENCES, ERFURT.
The queftion propofed laft year, which has not yet been
anfwered, is again put by the Academy as liky ea
A Prize Queftion; » “

What ufeful application can be made in chemiftry of the
temperature below zero of Reaumur’s thermometer; and
how far is it poffible, by artificial means, to lower the tem-
perature ? :

The prize for the beft anfwer is thirty ducats, and papers
will be received till the end of July 1803. ;

FRENCH NATIONAL INSTITUTE.
Prize Queflions.

The Clafs of the Moral and Political Sciences has propofed
the following queftion as the fubject of a prize:

To determine how the faculty of thinking ought to be de-
compofed, and what are its elementary faculties? .

The prize will be.a gold medal of the weight of fiye he&to-
grammes (about 7ol. fterling), and will be decreed in the
public fitting of Germinal, year 12 of the republic. Papers
will be received only to the 15th of Nivofe the fame year.

The Clafs of the Moral and Political Sciences propofed in
the year 9, as the fubject for a prize in geography, the fol-
lowing queftion : an

To compare the geographical knowledge of Ptolemy re-~
fpecting the interior of Africa with that which has been
tranfmitted to us by later geographers and hiftorians, except
in regard to Egypt and the coafts of Barbary from Tunis ta
Morocco?
_ As the papers tranfmitted to the clafs did not anfwer the
conditions, the clafs propofes the fame queftion as the fubject
of a prize for the year 11.

The prize will be a gold medal of the fame value as the
former, and will be adjudged in the public fitting of Meffidor,
year 12. The period for receiving papers the fame as above,

In the fitting of Germinal 15, year 8, the Clafs of the
Mathematical and Philofophical Sciences propofed as, the
fubject of a prize the following queftion :

‘To determine, by anatomical and chemical obfervations
and experiments, what are the phenomena of the torpor
which certain animals, fuch as the marmot, dormoufe, &c,
experience during winter in regard to the circulation of the
blood, refpiration, and irritability ; to determime what are the
eaqufes of this fleep, and why peculiar to.thefe animals, Ps
16

French National Infiitule. 87

-o Fhe. clafs was of opinion that-neither of the.two. memoirs
dranfmitted to it contained a. fafficientiHluftration of the fuby
ject-to, be: entitled, to. the prize, ,but/that the obfervations ap
them were, fufiiciently,interefting to, deferye honourable men-
non. The; author ofthe. memoir Ne,n1, »with, the, motto
Incerta facies inter vitam et mortem, does, not explain) the
necellary diftinGions:between the ways 1m which the different
claffes of animalsdpend, the, winter, and does not give fui,
cient details in-regard-to:their peculiar habits and the differ-
ences -in. their -mainaer, of lifes. He fpeaks only of fome of
the mammalia; betche gives anatomical details refpecting
the diaphragmatic menyes, and thofe known. under the name
of nerves of the eighth pair, as well.as theithymie gland, and
the mofcles which ,ferye to determine the ‘form which the
animal. affumes| during its) torpor. He. gives alfo fome en-
rious obfervations on the degree of temperature into which
the animal enters when in that ftate: it was chiefly on the
mus avellanarius’; the bat, ve/pertilio murinus ; the hedge-
hog; crizaceus europcus ; and the marmot, arGomys marmotia,
that thefe obfervations were made. di;
> One-half of the memoir Na. 2, having the motto Quid
mrum fi non afcendunt in altum ardua aggrefi? is devoted
to general obferyations on life and death, and on the different
modifications of life.. Without confidering thefe preliminary
obfervations foreign to the object which the author propofes,
in our opinion he has given them too much extent. He then
makes a diftinétion between animals which pafs the winter in
a ftate of torpor. He feparates thofe whofe torpor is properly
a deep and prolonged fleep, which:he calls vita foporofa,
from thofe whofe torpor is a real fufpenfion.of the vital func-
tions, which he calls vite interrupta. » Among the former
he examines the bear, urfus aréos; the hedge-hog; the bat,
the marmot, the dormoute, myouvus glis Schreber. 5 the wood-
rat or mufcardin, myoxus aan Schreber,; and the
hamfter, mus cricetus Linn. He enlarges :a great deal on
their habits, their. kind’ of life, and the manner in which
they pafs their fiate of torpor; but gives few details im regard
to their anatomy.’ He however obferves, as the author of
the former, the fize of the diaphragmatic nerves and the eight
trifplanchnic pair, particularly in bats, but does not: fpeak iof
the ftate of the thymus. Among animals of the fecond, he
diftinguifbes thofe which are provided with argans af .circus
Jation, as the amphibia, and thofe which haye no apparent
organs of that kind,’ asi is the cafe’ with infeéts; but of the
amphibia. he.examines only frogs, and» gives no details re~
{pecting the torpor of infects.. bis obfervations on the frog
ih F 4 ¢ are

~

88 Galvanic Society, Paris,
are very extenfive : he fapports them by very curious obferva-
tions on the refpiration of that animal’ the ftructure of ‘the
organs which ferve for that purpofe ; the properties he afcribes
to the fkin of thefe animals; the caufes which make theni
move during the time of their perfeét life, and thofe which
preferve them during their flate of torpor.” Ay
- We invite the authors to give more extent’ to thofe parts
of their labour on which they have befiowed the leaft care +
the talents they have difplayed in their memoirs do not permit
us to doubt that they will fully accomplith their objeét. >”
The clafs again propofes the fame fubje&.: The prize will
be doubled, and will confift of two'kilogrammes of gold (about
28ol. fterling). The memoirs muft be tranfmitted to the
fecretary of the Inftitute before the 15th of Meflidor, year 124
The determination of the clafs will be publifhed in the publie
fitting of Vendemiaire, year 13.

GALVANIC SOCIETY, PARIS.

The fitting of the Galvanic Society at the Oratoire, on the
r4th of October, was remarkable both on account of | the
prefence of the Jearned men and diftinguifhed philofopbers
who compole it, and of the nature of the experiments made
on cold-blooded and warm-blooded animals.

C. Aldini conduéted thefe experiments with a great deal
of method. The principal ones were as follow :

1ft. Several frogs recently fkinned exhibited in fucceffion
the phenomenon of a very fenfible contraction without the
interpofition of any metallic fubftance, and by the mere con-
tact of the nerves of each with the mufcles., vols

ad. The animal arc was feveral times obtained, and ren-
dered fenfible by the fame difpofitions as in the preceding
experiment.

3d. The phenomenon of fimultaneous mufcular con-
traction, in three frogs recently prepared, and placed at the
fide of each other in the fame direction, was produced at firft
by the aid of filver alone. But C. Aldini, being defirous to
prove that the fluid which acted on thefe animals was not
metallic eleétricity, changed the pofition of. the intermediate
frog by placing the fuperior extremity of the trunk of the
jatter parallel to the inferior extremities of the other two.
A contraétion being then obferved in the firft and laft with-
out producing any effect on that placed in the middle, C. Al-
dini concluded, that, as the fluid did not purfue the fhorteft
way of communication, it could not be the eleétric fluid of
metals, one of the general laws of which does not allow it to
deviate from: the fhorteit route.

6 si In

Academy of Sciences, Turin. 85

In ‘another feries of experiments the fame philofopher ex-
hibited the phenomena of the greateft excitability refulting
from the application of the Galvanic conductor. 1ft, Towards
the medulla oblongata of the head of a warni-blooded animal
recently feparated from the trunk. 2d, On the trunk itfelf.
3d, On the head and trunk; at the fame time making the
anus on the one hand, and the ear on the other, communi-
eate with the Galvanic battery. A {mall quantity of blood
{eattered over the table contributed, no doubt, to the energy
of this fimultaneous contraction of the two parts placed at a
remarkable diftance from each other. 4th, On a portion of
. the mufcles detached from the body of the fame animal.

5th. The crural nerve of a frog, brought into contaét with
one of the mufcles of the warm-blooded animal, exhibited
evident figns of contraétion.

6th. The heart of the fame warm-blooded animal, placed
in a veffel and fubjeéted to the impreffion of the galvanic
battery, gave no figns of excitability.. This, indeed, is one of
thofe organs which are fooneft decompofed after the death of
the individual.

The members of the fociety paid the utmoft attention to
all thefe experiments; and the prefident, C. Nauche, congra-
tulated in their name C. Aldini on the manner in which he
had conduéted them, and the zeal he’ had fhown to fupport,
by new facts, the theory of his illuftrious uncle Galvani.

From thefe facts it feems to refult, 1{t, That the animal
fluid fupplies the place in analogous experiments of the elec-
tric fluid propagated by metals. 2d, That this animal fluid
has‘no need of any other conductor than the organized parts,
3d, That the nerves and the mufcles are the fureft conductors
of this fluid; and, confequently, that éxperiments tried either
on the nervous’ plexus or the origin of the nerves muft pre-
fent the moft {triking and decitive effects. 4th, That the
different metals, in whatever manner applied, in cafes ana-
logous to thofe in quettion, perform no other functions than
that of favouring, more or lefs, the propagation of this uni-
verfal fluid, which penetrates eafily, and in preference to all
others, the neryous and mufcular parts of organized bodies.

TouRLet.

ACADEMY OF SCIENCES, TURIN.

The Galvanic Committee of this Academy, confitting of
profeffors Giulio, Vaflalli-Mandi, and Koflif continue their
experiments with great fuccefs, »

C. Giulio will toon prefent to the academy two reports ep

this

Td Academy-of Schenge ss. Turki.
this. fubjedts. In the firt, \afierjrecurring.to, the experiments
avhich-he made in 17925-4793» and 47945,0n ,feveraliplantsy
dn order to how how far they were; fenfible to the Galvanic
~ influence’ by. the fimple medium, of armang, and of, metallic
ares, he, gives an account of, new! expernents made! lately,
an conjunction with Vaftalli- Handi, on: the! different, fpecies
of fenfitive plants, fach, as the; mimo/a.pudica, the, mimo/a
eafitiva, Ahe mimofa afperatay and the rr Dyfenfetivay,w hich
»that the mufeles of their leaves are pigafible 40 the: in
HENCE of the Soalsranie'« agent called. forth by the Viol ltaic

ren the: ened he gives, an Pe ser of Ha, pallies eo
Dy experiments made onda man decapitated, September 28th,
in one of the halls of the national colleges, The principal v
thefe refults were as follow: ;

vaft, By-making one .extremity of the ri peutmauaieate
siiady the interior of one ear moitened with) a/folution, of mus
Fiate of, ammonia, and the other extremity of, the pile with
the other ear, very firong contractions were , produced in the
mufcles of the face: but the contractions ofithe;} te temporal
mufcles, the pterygoid, and mafleter, were particularly ftrik-
ing, for they elevated. and. agitated the lower, jaw with fo
much force, that the gnathing of the teeth, was | diflingtly
heard at the diftance of feveral “feet.

2d. By eftablifhing a communication between the fpinal
marrow and. the large: nervi.fympathetici and yagi,armed,
and-between different resions of the breaft moiftened with the
fanie folution, and the “other extremity of the pile--hefore
the cavities were opened very ftrong tetanic, fhocks weréob-
sained throughout the whole bedy ; fuch violent palpitations
of the heart, that the band,applied on the region)of the fifth
and fixth: ribs was-ftvongly firuck by them ;,1afpiyations and
expirations, with a bifing noife which accompanied the en-
trance and efcape of the air.»
gd. After opening the breaft the palpitations of the heart
fill continued, and could be difttnctly perceived: when, they
had ceafed, they were renewed by. eftablifhing a,communica-
tion. Ladies the heart and, the pile, the large neryi fympa-
thetict audi vagi and the pile.

4th. By arming the abdominal aorta and the plexus cce-
liacus, and then making them communicate with the pile by
means of ‘two. refpedtive ares, amet ous were * produced 1 in
the abdominal aorta. —’ Ther

Thefe experiments, added*to oties annptineeds ima mem

fd “to the academy on the 15th of Auguft Jatt, leave’no
‘ doubt

Academy of Sciences, Turina \ or

doubt .in regard to..the irritable mufcular’ contractilityoof
the arteries, and of the influence which the nerves have: in
their.action,

5th. By arming the anterior nervous branches of the lat
dorlal nerves and of the thoracic conduit, and efiablithing a
communication between that conduit and an extremity of
the pile, and the armed nerves and the other extremity,
evident contractions were produced in the thoracic canal.
Phyfiologitis know what difputes have taken place. for and
againit the irritable contractility of this canal. The experi-
ments of the Galvanic committee of Turin remove all doubts
on {he fubject: in a decisive manner it prefents, for the firtt
time, an trefragable proof of the irritability of the canal of
the chyle, and of the exiftence of mufcular fibres in the tiflue
of that canal. vil

6th. One of the eyes was plucked from its orbit, and laid
on a plate of glafs armed with a plate of lead, fo, that the
pofterior part of the ball of the eye, the trunk of. the optic
perve, and the nervous branches of the lenticular ganglion,
Were in contaét with the plate of lead: a communication
was then formed between the plate of lead and one extremity
of tlie pile and the {clerotica, and between, the tranf{parent
cornea and the other extremity of the fame pile, by means
of exciting arcs, to

The fpectators were greatly aftonithed to fee the pupil
inftantly contraét. An incifion was made in the cornea 3 and
a fine gold wire being brought into immediate contaé with
the iris and the laft filaments of the ciliary nerves, a move-
ment was obferved in the iris, anda greater contraction in
the pupil. There are irritable fibres then in the iris, note
withftanding what many authors have faid to, the contrary.
But what is the direction of thefe fibres ?. The profeffors pro-
pofe to make this a future object of refearch.

7th. By introducing an arming of lead into the anus, and
making it communicate with the pile, while another com-
munication was eftablithed between the furface of the ins
teftines and the other extremity of the pile, evident contrac=
tions were produced in the mufcular tunic of the inteftines,
efpecially when uncovered by the feparation of the exterior
membranous tunic, a continuation of the peritoneum.

8th. A long portion of the right anterior mutcle of the leg
being extended on a plate of ae armed with two plates of
lead, the two extreinities of the mufcle, when touched by the
two. ends af the! are, without the intervention of the pile, ap-
proached ¢ach other, and the nerve immediately became
: Ww fhortened

92 Vaccine Inoculation. Antiquities.

fhortened one» half. \Thefe motions took place’ even wher
the arming was removed. .

Thefe experiments were made in the prefence of the com-
miffary-general of the police, feveral profelfors of the Athe-
nzum, the members of the academy, and a great number of
other enlightened citizens. > 0

8 eS —— = a

XVI. Intelligence and Mifcellaneous Articles.

VACCINE INOCULATION.

Tur following letter, addreffed by A. van der Velden, fur-
geon and man-inidwife at Workendam, to the editor of a
Dutch Journal intitled Algemcene Konflen Letter-Bode 18025
No. 41, we have tranflated from that work.

*¢ By the encouragement of fome friends to humanity, and
fome of our principal medical men, who have exerted them-
felves very much to recommend the cow-pock inoculation at
this place, about 140 have been inoculated by me and
J. Heilijers, furgeon and man-midwife at Wondriehem. Iam
therefore induced to fend you the following information,
with the hopes that it may contribute to the prefervation of
thofe who are fuffering under the fmall-pox. In the courfe
of the prefent month [was called in by an inbabitant of this
place who had the misfortune to lofe two of his children by
a confluent fmall-pox of the moft malignant fort, and the
third, the only one remaining, was exceedingly ill of the fame
diforder. Convinced that no injury could arife to the pa-
tient, I applied the vaccine, being provided with a‘lancet
armed with good matter, and had the happinefs to find, the
fecond day after the vaccination, that the fymptoms of the
fmall-pox were much mitigated ; but on the eighth, and
particularly the ninth day after the vaccine inoculation, the
puftules of the natural pox dried up and fell off. In the
mean time the vaccine continued to operate, and the fol-
Jowing day the child was perceptibly better, and no bad con-
fequence enfued: » '“

* Tf you think this fimple cafe worth infertion in-your
Journal, as'a'further proof of the power and utility of the
vaccine, it ‘will give me great pleafure, efpecially if it fhall
benefit the public, and excite the attention of others,”

ANTIQUITIES.

M. Akerblad, a learned Swede, has opened a new field to
the lovers of antiquities, and enlarged the boundaries of our
k knowledge,

Antiquities. : 93
knowledge, by overcoming difficulties fo great, that the firft
critics of Europe have hitherto confidered them as unfur-
mountable. He has immortalized himfelf by a difcovery
which will form an epoch in literatures? and has given a fo-
lution to one of the moft curios problems in erudition by
difcoyering the antient alphabet of the: Egyptians, and ana=
lyfing it-in his Lettre fur VInfeription Egypiienne de Rofette,
Paris, 8vo. del’ Imprimerie dela Republique, year 10.

This interefting pamphlet is fold at Paris by Treuttel and
Wiirtz, bookfellers, Quai Voltaire, as well as the following
work of M. Akerblad, who feems to have been born to un-
veil the myfteries of the Eat: Infcriptionis Phenicie Oxo-
nienfis nova Interpretatio, Parifiis, an. 10, 8vo.. This is a
new explanation, much: happier than the preceding, of a
Phenician infcription which had exercifed the ingenuity ot
the learned Barthelemy and of Simon.

M, Akerblad had before explained, in the Memoirs of the
Academy of Gottingen, for 1801, another infcription which
he found in the city of Athens. He explained alfo in the
Magazin Encyclop-digue, Ventofe, year 10, an infeription in
a Coptic manufcript, which it appeared impollible to decy-
pher, becaufe’ it was written in the running hand of the
Copts, till then unknown. It only remains for us to wilh
that M. Akerblad may proceed to London to copy, in the
Britifh Mufeum, and publith with his tranflation, the famous
Coptic manufeript of Dr. Afkew intitled Pzjis Sophia,
which would throw great light on the antient philofophy of
the eaft, :

D’ANSSE DE VILLOISON,
of the National Inftitute of France.

The Society of Antiquarians of London have caufed an
accurate delineation to be made of the Greek infcription, ac-
companied by two others in honour of Ptolemy-Epiphanes,
and found on a ftone in Egypt, which has fince been
brought to London. This delineation of the Greek infcrip-
tion is of the fame fize as the original, that is to fay, 1 foot
gipehs in height, 2; feet in breadth, and containing 54

ines.

A copy tranfmitted to the Royal Society of Géttingen was
laid before the members in their fitting.on the 4th of Seps
tember by profeflor Heyne, accompanied with a commen-
tary. In the fame fitting was laid before the Society of
Gottingen, a paper intitled Previa devuncatis gras vocunt
ser ipiaones Perfepolitanis legendis et explicandis Relatio, by
G. I, Grotefend, colaborator in the {chool of Gottingen;

who,

2 Ajtronomy.

who, without being an orientalift, ‘has accidentally fallen on
the means of explaining this obfeure writing merely by’his
expertnefs' in the art of decyphering. © The refult of his:re+
fearch is, that! theféwedge-like figures are aétually chatac+
ters, and not fyllables, which proceed from right 'to lefts! that
the language of thefe infcriptions is Zendic; and that-all*the
Perfepolitan infcriptions which he has hitherto’ been’ able to
explain relate to Darius Hyftafpes, and Xerxes.) 0% ° ©

4 ASTRONOMY.

ft. One of the moft fingular phanomena in aftronomy
is, to fee the ftar Algol decreafe in light every three days.
I obferved it very fenfibly on the 29th of September. It :was
at 11 hours 15 minutes mean time that its light was ‘the
leatt.

ad. The eclipfe of the fun on the 27th of Augutt, which
I could not fee at Dijon, was obferved at Viviers by C, Fla-
guergues, and at Marfeilles by C. Thulis. The end at Vi-
viers, 18h. 13m. 24”5 at Marfeilles, 18h. rrm. 24", 1
thence conclude that the conjunction took place at 19 h.
gm. 46” true time at Paris.

3d. C. Pons, keeper of the obfervatory of Marfeilles, has
difcovered a fecond comet. I fent him a fmall prefent. I
have requefted the minifter to fend him one more confidera-
ble, in order to encourage amateurs to fearch for comets,
which are now the great-defideratum in aftronomiy. '

th. I have carefully examined the Esyptian Zodiac
which C. Denon has publifhed. I have obferved that the
ficn Cancer is found in the two lines ; it is at the end of the
afcending figns and the commencement of the defeending.
This feems to indicate clearly that the folftice was in the
middle of Cancer. This would go back to 1470 years be- _
fore the vulgar era. But I have fhown in my Aftronomy,
that in the time of Eudoxus, 370 years before the vulgat
zra, the Greeks followed this method fron’ fome antient
Egyptian tradition, which they did not corre&t-becaufe they
made no obfervations. »

-5th, The fmall tables. of logarithms juft publifhed, being
the moft correct and convenient, the minifters of the -inte-+
rior and the marine have determined that they thall be fent
to all the national {chools. DELALANDE.

NEW COMET.

In our'laft. we announced this difcovery by C: Mechain on
the 28th of Auguift, at nine in the evening, im the conftella-
tion of Serpentarius, It was rifing rapidly towards the North

Fe pole,

Tantalite, anew Metal. Silver and Tron oF

poles followine the right» fide of Serpentarius andi the oppo=
fite fide of Hercules. It was near enough to be-obferved by
the naked eye. i los
On the 2d of September C. Mechain tranfmitted to the
Inftitute a report on this comet. The elements he affigned
to it were as follow: ib coon? 109 MOHYUD .
Mean time = =.=) =.) g4h 24h 6
» Right afcenfion + +) = 249° 18 y
‘1s South declination’ +> + 6 (11 3%.
/ TANTALITE—A NEW METAL.
- A new metallic fubftance thas lately. been :difcovered in:
Sweden. It was extracted by the celebrated chemift Ekeberg
from a mineral given to him by M. Geyer. This mineral,
found in Finland, had been claffed among the ores of tin.
M. Edelerantz,; of the Academy of Stockholm, tranfmitted
afpecimeh of it to Delametherie,:who gives the following
defeription of it. It has a blackith colour, with the metallic
afpect ‘of ‘eryftals of oxidated tins) ‘Its colour is equally
dark ; its gravity is confiderable; it flrongly fcratches glafs.
Several facets are diftinguifhed in it, but the cryftal. is im-
complete. M. Ekebero has extraéted from this mineral’a
new metallic fubftance, to which he! gives the name of Tan<
talite. ‘It forms the twenty-third metallic fubftance.
| SILVER|AND ERON. acai
--C. Gayton announced,:25 years ago, that iron and filver
hit together into perfect fufiomsformed two feparate but
tons adhering by their furfaces. He thought be could thence
conclude, contrary to the opinionsof Gellert, that thefe two
metals cannot be alloyed. oni a . .
The ingenious experiments of Coulomb on magnetifn
having rendered it neceflary for that philofopher to procure
metals warranted free from iron, C.:Guyton propofed to hint
to try a button of filver from whieh at appeared'that nature
itfelf had feparated the iron, r¥bq
© The filver; indeed, did not contain aiquantity of iron which
could he rendered fenfible by chemical re-airents, finice afo+
Jution of it did not give an atom of blue with pruffiate of foda.
A portion of the fame fragment exercifed a fenfible aétion on
the magnetic bar; and Coulomb, having fubjected it to his
magnetic apparatus,foundthatit-contained a thirtieth of
iron.
It then became of importance to examine whether iron did
not contain a certain quantity of filver. This C, Guyton did
with bis ufyal ability. He affured himfelf that in iron there

y] 1s

96 Rapid Diforganization of the Human Body:

is an cightieth, or nearly fo, of filver intimately combined ;
and that this quantity is fufficient to give it very remarkable
properties, fuch as extraordinary hardnefs, and a fracture
which prefents, without continuity, rudiments. of cryftalliza-
ton. ; Teas
C. Guyton concludes from thefe experiments on filver and
iron, as well as from thofe which he made on iron and lead,
that it can no longer be faid that thefe metals refufe to form
an alloy, and that there is atually an union in their fufion ;
but that by a real quartation the greater part of the two metals
Pn while cooling in the ratio of their weight, and ex-
actly as copper and lead feparate in grand metallurgic opera-
tions.

RAPID DISORGANIZATION OF THE HUMAN BODY.

On the night of the 16th of March, 1802, in one of the
towns of the State of Maffachufetts, the body of an elderly
woman evaporated and difappeared from fome internal and
unknown caufe, in the duration of about one hour and an
half. Part of the family had gone to bed, and the reft were
abroad. The old woman remained awake to take care of the
houfe. By and by one of the grand-children came home,
and difcovered the floor near the hearth to be on fire. An
alarm was made, a light brought, and means taken to ex-
tinguifh it. While thefe things were doing, fome fingular
appearances were obferved on the hearth and the contigu-
ous floor. There was a fort of greafy footand athes, with re-
mains of a human body, and an unufual {mell in the room. All
the clothes were confumed ; and the grandmother was miffing.
it was at firft fuppofed fhe had, in attempting to light her
pipe of tobacco, fallen into the fire, and been burned to
death. But on confidering how. fmall the fire was, and that
fo total a confumption could {earcely have happened if there
had been ten times as much, there is more reafon to con-
clude that this is another cafe of that {pontaneous decompo-
fition of the human body, of which there are feyeral inftances
on record. It is to be regretted the particulars have not been
more carefully noted.

[ 97 ]
OVI. Ox Painting. By Mr. E, DAYEs, Painters
Essay VI.
On Compo/ition or Difpofition.
but in fuch order all,

As, though hard wrought, may feem by chance to fall.”
Duke of Buckingham.

Cowposrrion is the forming of a whole by the union
of various diffimilar parts; or, in a more painter-like fenfe,
the art of arranging the figures and other materials of a pic-
ture in fuch a manner that the whole may appear as if the
Tefult of chance, though produced by the moft confummate
art.

Before we proceed to offer fach rules as are to be extracted
from the works of the moft efteemed mafters, it may not be
improper to premife what previous knowledge is neceflary to
enable us to produce a compofition.

When we have occafion to fpeak of the works of certain
artifts, we with at all times to be underftood as referring
through them to nature, for it muft ever be remembered thaé
art cannot furnifb its own rules.

Some who have written on the arts have recommended
particular books for the ufe of young artifts; which is fup-
pofing a certain quantity of information fufficient to make a
painter. Where he is to begin his inquiry every one knows 5 |
where to ftop, no one can tell: one thing is certain, there’
is no danger of too much knowledge making him fpoil his
work,

It is of the firft importance to imagine well our picture.
To this end we muft take every means to become well
acquainted with the hiftory whence our fubjeét is drawn,
that we may become familiar with the characters we are to.
reprefent: hence a reference to their lives becomes neceflary,
_ that we may not miftake a bad man for a good one from the
fhow of one good aétion, This is not all; time and place
mutt be attended to, that we may not confound the cuftoms
of one people with the manners of another. The country,
alfo, fhould be characterized by its trees, rivers, monuments,
and public buildings, as well as the inhabitants by their drefs
amd inanners. i
* All this, nay more, being abfolutely neceffary, how is it
pofible that an artift with a little reading can accomplifh a
work like a hiftorical pi€ture? As well might we fuppofe the

- Vou, XIV. No. 54. G merely
» November 1802.

tose

98 On Painting.

merely reading Homer fufficient to enable us to defign from
that author without any previous hiftorical information.

He who firft acquires a knowledge of geography will not
only better underftand hiftory and biography, but receive a
higher relifh for them than had he followed a different order
of reading. What gives us an intereft in Alneas, but our
fuppofing him the founder of the mighty empire of Rome?
Otherwile, he becomes a mere robber.

As all this knowledge cannot be obtained without much.
attention, we fhall find great advantage refult from making
memorandums under their refpective heads of the cuftoms,
manners, buildings, and other circumftances conneéted with
hiftorical painting; by which means we fhall collect a mafs
of information at all times ready to refer to, and that with-
Out its interfering in the leaft with our practical ftudies.
Lord Bacon jultly obferves, ‘* The proceeding upon fome-
what conceived in writing, doth, for the moft part, facilitate
difpatch ; for though it fhould be wholly rejected, yet that
negative is more pregnant of direction than an indefinite, as
afhes are more generative than duft.””

Thole who propofe to themfelves to purfue the great and
arduous tafk of hiftory-painting, fhould be careful to guard
againft commencing their career too foon, or before they have
obtained a ftock fufficient to that end: fome have ftarted with
fo flender a capital that it has been confined to colour, chiaro-
Jfcuro, with, now and then, a fuccefsful compofition; requi-
fites that do not fink below the fuperficies.

The acquirements neceflary to qualify an artift to purfue
the great and important part of the art we are treating of, are
many: he fhould poffefs a thorough knowledge of the human
figure as far as it regards his art, and its attire, with land-.
fcape, architeCture, chiaro-f/cure, and colour: he fhould be
well read in hiftory, antiquity, and the belt poets; to
which he fhould join a tei of practical geometry,
as the foundation of perfpective; with that part of optics
called chromatics, as it explains the colours om light and of -
natural bodies; and, withal, poflefs a tolerable facility of
hand. Nothing can be more dificult than to fill up the
character of a great artift, particularly if he propofes to raife
a juft and Jafting reputation ; and, not content, like the ge-
nerality of the profeffion, to produce trifles, extends his views
beyond the prefent generation by the cultivation of works
that may flourifh in future ages. To do this, as well as the
above acquifiuions he fhould be endowed by nature with
noble and elevated fentiments; a ready and warm genius to
invent, accompanied with the greateft coolnefs to arrange ;

penetration

On Painting.’ Hf 69°
perietration ‘to apply ‘a juftnefs of charaéter, with patience
and induftry to carry him through the detail: in faét, his
nature {hould be fo formed as to poflefs the contrarieties of
hot and cold; that is, with the greateft vigour fhould be’
united the greateft cattion.

O thé godlike attribute of extending benefits beyond the

ave! Where are now the antient heroes? Their names are
Feuiaaly remembered, aid their mifchiefs have long ceafed to
trouble ; while the labours of a Homer, a Virgil, a Shake-.
fpeare, and Milton, with along lift of worthies, give bread
at prefent to thoufands! .

Some one has well obferved, “ The great end of books is
to fet the mind a-goin?” all’ we can hope from our efforts
is, to raife in the mind that fpirit of inquiry that may ulti-
mately lead to an imitation of the great, the noble, or beau-
tiful: all the réft is froth.

It was their high notions’of the art that led the old matters

to fuch an exalted perfection as to become the admiration of
the civilized part of the world, and placed them among the
firt order of mortals, or thofe who have extended their fervices
beyond their being.
Anger, hatred, and revenge, are paffions poffeffed by every
one in common with the brute; but to underttand that in-
finitely remote point of pérfe€tion which coniiitutes the foun-
dation of true art, is the reward of few.

It is a misfortune for the art, that every one imagines him-
felf a critic in painting; all are tried by their peers but the
poor painter: but let thofe who are in affected raptures at the
touch of a pencil, or the neatnefs of handling, recollect they
are the moft trifling and infignificant parts of the ait; ‘criti-
cifm fhould be general in all great works: it is a common
precept in art, that an attention to the whole fuperfedes all
confideration for the parts *.

In wit, as nature, what affeéts our hearts
Is not the exaétnefs of peculiar parts 5
’Tis not a lip or eye we beauty call,

But thé joint force and full refult of all.
Pope’s Effay om Criticifms

* It mutt not be underftood that the above precept goes to recommend
a negleét of the fubordinate parts. Over-finithing (that is, the nicely des
fining the form of each part of an objeét, as a hand, foot, &c.) is not one
of the faults of the Britith fchool. This fault, of want of care in making
out the parts, is by fome improperly aftribed to fir Jofyua 57 0 ai
That great man was not without his defects ; but we, as rational beings,
fhould avoid them. Lt wouid ve a poor juftification for the practice of a
vice, becaufe we faw it in another. Iris much to be doubted, whether
the pérfeétions of a great mafter will ever be properly felt by the mere
imitator : the reverie is certain.
Ga Petty

106 On Painting.

Petty criticifm fhould be punifhed with filent contempt...
We might as well ‘ hew blocks of marble with a razor,” or
*€ whiftle to mile-{tones,” as attempt to convince fome people.
There is an applaufe which is fuperior to all others, that is,
our own, from a conviction of well doing; or, in other words,
a-confcioufnefs that our induftry is rewarded with improve-
ment. He who is too anxioufly eager for the applaufe of
others, exchanges independence for uncertainty, and happi-
nefs for difappointment. Befides, he is in danger of falling
into a ftyle familiar and common, fuch as may belt {uit the
ideas of ordinary life and vulgar opinion. We mutt be care-
ful not to refine our delicacy to too high a pitch, otherwife
we {hall render ourfelves liable to be wounded by every petty
criticifm. Many with whom our fituation compels us to have
an intercourfe are no judges of art; others are influenced by
prejudice ; many delight to wound: but, whether the obferva-
tion be the refult of ignorance or vanity, the beft mode of
punifhment will be neglect,

We have already noticed, under Invention, the two cha=
racters of compofition, as the grand and picturefque ;. that the
former applies to grave and ferious fubjects, while the latter
appears to aflociate beft with gay and {portive ones. Beauty
and grace not only delight in, but derive their greateft power
from, mild variety: hence one of the great beauties in our
eommon writing charaéters refults from the fwell or the op-

ofition of force and delicacy in the lines, which give grace
independent of form: the fame thing enriches and adds {pirit
to a mafterly outline, to which if we join fine (we mean true}
form, it will poffefs the firt or higheft kind of excellence.
Among the profeflion there is great difference of opinion re-
lative to compofition ; we fhould therefore wifh to be under-
flood as offering thofe rules that relate to matters of tafe with
delicacy and modefty, for fear of forcing genius into one par-
ticular track of operation.

Nothing can be more falfe than to fuppofe the art of com-
pofition fubject to fome pofitive law, or that the figures of a
yroup. fhould be invariably compofed under fome particular’ ,
form. Men who look to pictures, and from them obtain all their
knowledge, are apt to run into this error, and fuppofe, be-
caufe they fee a group in fome celebrated pi€ture make fome-
what of an angle, that all figures to be well put together muft
aflume the triangle. Others, in contradiction to that doc-
trine, maintain that the true Venetian method of compofition
recuires the group to incline diagonally, that is, running
from corner to corner of the picture, afferting that the former
method “is barbarous and Trench: another jet of men call

‘ the

er,

On Painting. Ior

fhe horizontal line /mplicity, and the true Roman method,
expecting to fee a range of heads of an equal height running
throuch the greateft part of the work.

He who wifhes to°affe&t with forrow or melancholy can
only expeé to fucceed by the removal of whatever may. be
likely to pleafe, either from variety and contraft of forms,
brilliancy of colour, or ftriking effect of hight and fhade ; and
one great aid will refult from telling the ftory with few figures,
which greatly adds to fimplicity.

The great reafon why Raphael is preferred for compofition
is his poffeffing a ftyle more fimple and expreflive than any
other. Simplicity appears to have marked the characters of
the Roman and Florentine fchools, as alfo that of the Ca-
racci; after whom we mutt place Pouffin, Le Sueur, Bour-
don, and fuch others as have affefted the faine fimple and
expreflive manner.

Le Bran, though an artift of great merit, has, in many
inftances, fo crowded his compofition with incidents, that
the attention is entirely taken from what ought to conftitute
the principal feature, and the mind becomes diftraGted amidft
a multitude of events: witnefs his Crucifixion, and Slaughter
of the Innocents. Expreffion derives much of its force from
fimplicity.. Sterne, in his Sentimental Journey, was obliged
to take a fingle captive to give force to his defeription. What
ean more firongly affect our feelings than his Maria? A
multitude of objeéts rufhing on the fight defiroy intereft, and,
in fingle objects, too many parts produce the fame effect:
hence the neceflity of not over-crowding with ornaments.

It appears pretty certain that the fhape of the group muft
depend preaty on the nature of the fubje&t. A triumph mutt
neceffanily ailume a different figure to a fpectacle like a de-
{cent from the crofs, becaufe it would be fo in nature,

Diverfity does not carry with it fo much art, or the appear-
ance of art, as is generally fuppofed ; for, if we diligently at-

‘tend to nature, we fhall find an infinite variety of formed

roups refulting from the difpofition of fome men to fit,
others to ftand, the contraft of children with adults, men on
horfeback, the irregularities of ground, and a variety of other

- ¢ircumftances,—all tending to produee a diverfified and irre-

ular mafs, probably affuming, more frequently than any
yther, a general figure approaching to the pyramid.

If we examine the ott approved compofitions of the Ro-
man, Venetian, or other {chools, we {hall find not only the
general difpofition tending to the pyramidal figure, but each

roup taken feparately,—with this difference, that in the Ve~
¢tian and Flemifh it is rendered more exceffiye, Hence,
ei beats G3 from

‘102 On Painting.

from a dafh of excefs in Rubens he becomes a better matter
to ftudy than any other, but he mult be ftudied with caution,
The clofe adhefion of his figures points ont the method of
compofition, the ftriking and con{picuous manner of arrange-
ing his tints evinces the plan purfued in grouping the colours;
while the union of fhadow with thadow, and Tht with light,
is feen in the breadth and vaitnefs of his maties. By his ex-
cefs we may learn, as from Diogenes in morals, who ob-
ferved he acted like muficians, who gave a higher tone in
order to indicate a true one.
The affectation of contraft in fome artifts is abominable ; it

looks ftudioufly abfurd to fee a woman lying on the ground
with a child at her breaft, and another playing near her;
befides the common trick of mixing, in quantum fufficit,
naked with clothed figures; old men with young ones; fide
oppofed to the full face; the contraft of violent motion
with languid attitudes; and a thoufand other petty arts to
trap the unwary. Such violent oppofition will never pleafe
the judicious. Where the higheft degree of the piéturefque
is intended, it fhould never be carried to excefs. How ridi-
culous would it appear in a landfcape to fee trees crofiing
each other at right angles, or one vertical and another hori-
zontal! In this inftance we may take an example from na-
ture, whofe progrefs from feafon to feafon is by gentle and
almoft imperceptible degrees, and not by violent oppofition
from heat to cold. By the fame rule, violent fore-fhortenings
fhould be avoided; a little adds dignity, but, in general, the
figures had better be compofed than otherwife. We fhould
be careful of miftaking blufter and rant for fpirit and great-
nefs. ‘* Be not too tame neither, but let your own difcre-
tion be your tutor: fuit the action to the word, with this {pe-
cial obfervance, that you overftep not the modefty of nature.”
- Weak minds are apt, when they attempt the éxpreflive
ftyle, to give their figures the wild and extravagant attitudes
of lunatics. That grave dignity obfervable in the works of
the Florentine and Roman {chools has entitled them to the
firft place in compofition: the next is jufily held by the Ca-
raccl, whofe pupils, as they loft fight of dignity, fubftituted
buftle and {how for fimple truth. The ftyle of Guercino is
forcible and ftreng, but lefs elegant and beautiful than Guido,
which is eafily perceived in the extremities. Pouffin has
great fimplicity in his compofitions, though his figures are
fometimes too much fcattered. He is remarkable for not
fuffering any low or vulgar thought to break in on the dig-
nity of his ftory; an error fometimes committed even by
Raphael. There are admirable traits of the true Roman

8 ine ~ fimplicity

On Painting’. 103

fimplicity in the pictures of Le Sueur. They are rare jewels 5
and Le Brun’s floning St. Stephen is highly claffical.

Mott of the writers on compofition in painting feem to
imagine it to depend on. contraft, and recommend it in the
firongeft manner ;-but violent oppofition, as before ftated, not
only deftroys fimplicity, but is of all affectations the moft
difeutting. If oppofition or contraft-were a criterion of ex-
cellence, the moft violent would become the moft perfec ;
and, like a caricature, the more unlike nature the better it
would be. Variety or contrapofition is certainly neceffary ;
but the degree cannot be afcertained by weight or meafure,
it muft be learned from the works of efteemed matters.

‘Common fenfe muft dictate the neceffity of not making

all the attitudes alike, and alfo keep us from a contrary
excels.

In a fine compofition we fhall difeover, by an attentive
examination, all the parts fo depending on the whole, that
the removal of any object would deftroy the general good
arrangement.

That variety neceffary to the perfection of a group fhould
be difplayed in a fingle figure, efpecially if it be a beautiful
one. If the figure is feen in front, its grace will be increafed
by fhowing the face in profile, with a flight inelination in
the cheft*: one of the legs being ftraight, the other fhould
be thrown back; and fo of each limb ¢: but this variety muft
depend on the nature of the fubje&t, as fuch a contraft would
ill become a philofopher, apoftle, or fenator.

A fingle figure may be confidered as a group im itfelf, and
fuch a ftudied one would by no means unite with many,
any more than one taken from a number would do as a fingle
figure.

“The contraft obfervable in Raphael is not an affectation of
variety, but the refult of confummate judgment, where the
erect and inactive figure is introduced to give energy and
motion to the active. Contraft in him is the refult of ne-
ceflity arifing from deep reflection, not the ftudied and in-
fipid oppofition of_an old man, a young woman, a boy and
a girl, which we often fee in pictures. He knew well a
philofopher or aa apoftle would not move like a foldier, a
Virgin like a matron, or children like adults; which appears
to make part of that variety obfervable in. his works. He

* See Effay on Grace in the laft number of the Philofophical Maga-
zine, and the plates. :

+ See the Venus de Medicis, Apollo Belvedere, and others, remavka-
ble for grace.

G4 appears

104 On Painting.

appears alfo to have preferred the a¢tion to its termination 3
which renders the ftory more clear, and leaves the {peétator
delighted with a fufpended motion, and in expedtation of its
terminating. A man reprefented in the act of walking, and
as having terminated his ftep, will not have fo animated an
effect as one not having finifhed it. Much of the beauty of
the Apollo Belvedere arifes from the ftate of ation he is re-
prefented under. We almoft imagine he is aétually moving
when viewed in front. ,

In a great matter, every thing is the refult of reafon >
if a limb, fuch as a hand or foot, is concealed by drapery,
it does not arife from idlenefs or ignorance ; it is done to give
beauty to fome principal members, by not making too great
a difplay of parts, or to avoid what would otherwile produce
an ugly form.

The grand or expreffive ftyle will ever rank firfl; the other,
as in the hands of Lanfraneo, Cortona, &c. is only the art
of agreeably filling a Jarge picture with figures, or merely!
pleating the eye: it may juftly be termed ornamental, and
ranks infinitely below the pure picturefque. In all works of
art, the philofopber will inquire whether the bead or the band
is moft employed. Pouflin, though admirable in compofition,
often excels’in the acceflary parts. In his Pyrrhus, the
figures, and diftant ground over the river, are more beautiful
than the principal part; a prodigality avoided by Raphael;
nor is he fo noble in his beft thoughts; and his women are.
often ordinary. We with to be underftood as always diftin-
guifhing between the grand ftyle and the piéturefque. In
the former, the utmoft fimplicity is to be obferved in the ar-
rangement, and every thing like artifice avoided; while the
latter admits of, and derives much of its character from,
variety.

In a group: the artift generally prefers unequal numbers,
as 3, 5,7, 0r 9, which unite with a better grace and afford a
greater variety than any other; but, where equal numbers are’
ufed, thofe compofed of two unequal are belt, as 6, 10, and
14; but double pairs will ill accord, as 4, 8, 12, &c. The
principal part of the flory ought undoubtedly to occupy the
centre of the picture, and the group, by affuming a rotund
or femicircular form, will aifift the light and fhade, and en-
able us to bring the principal figure in hght, as well as to,
procure mafles by combining the fhadows of feveral objects
inone. In this refpeét Raphael has difplayed fo much judg-
ment, that it appears from his works evident that he would
have proved a great mafter in light and fhade had he been

permitted

On Painting, ¥Os

permitted a longer life: however, he did enough to furnith
the hint to the Venetian fchool.

In whatever way we may difpofe our group, the principal
figure ought to be rendered confpicuous, either from fitua+
tion, colour, drapery, light, or from all thefe combined. To

stalk about, “ effect of light and fhade,”’ and thereby attempt

to juftify an impropriety, would be reducing painting to a
fiyle merely ornamental indeed! and make paintings of no
ufe beyond ftopping a hole in the wall. :

As in the drama the hero of the piece has a greater part to
fuftain to diftinguifh him, fo ours muft, ‘as it were, lord it
ever all the other objects. ;

Nor pamt confpicuous on the foremoft plain
Whate’er is falfe, impertinent, and vain;
But, like the tragic mufe, thy luftre throw
Where the chief aétion claims its warmeft glow.
Mason’s Fresnoy.

Tt muft not be underftood that the principal figure fhould
be more laboured or finifhed; that would deftroy the unity
which ought to prevail through the whole. In forming our
groups, the greateft mafs ought to be in the middle, and the

ittle or feattered parts placed on the edges to give the whole
a lightnefs; while fome places require to be left blank for
the fake of repofe—for, though our picture fhould be filled, it
fhould not be crowded. As we muft alfo feck to obtain pro-
fundity proportioned to the greatnefs of the group, we fhould,
to give the whole a pleafing air from a variety in its form,
avoid placing the figures im a file. Rubens, whofe art in
grouping bis figures is great, fometimes runs into excefs by
attaching them too much together, fo as to make them appear
to cling as mfeparable; but, as before obferved, his vices
teach us what is right, The golden mean muft form the
objeét of our purfuit, we fhould avoid a monotony of forms
as well as too great a contralt; a number of extremities fol-
Jowing each other in the fame Jine ‘will generally produce a
bad effect. We fhould alfo avoid fhowing them in the fame
oint of view. Ponflin’s Sacrament of Baptifm is an excel-
lent example, where many figures are pointing, al] differing
from each other.

In exhibiting the naked we are bound to fhow the molt
beautiful parts, which is, generally fpeaking, all the joints.
The neck and fhoulders in the male o form a fine mafs
in a group. But, above all, we fhould never conceal the ex-
tremities, from the power of expreffion they difplay, as well
@5 the room they allow for the {kill and abilities of the i

a

106. On Painting.

In the female, the naked is ever pleafing, while an artful
concealment will augment the beauty and grace,

But treat the goddefs like a modett fair,

Nor over-drefs, nor leave her wholly bare; -

Let not each beauty ev’ry where be f{py’d,

Where half the kill is decently ro hide, Pore.

If our ftory requires more than one group, the fame laws
mutt influence us in the conduct of each,—they fhould cer-
tainly not exceed three. The principal one fhould prevail
over the others; and, by placing it near the centre, or in
the feeond ftage of the picture, we hall afford the fpeétator
a better opportunity of feeing it, and alfo furnifh ourfeives a
better opportunity of furrounding the principal group with
the other objects.

As we are bound to fupport an equilibrium in our compo-
fition, we ought not to crowd one part of the picture, or leave
another too naked; but this muft be done without adding
weight to weight in a horizontal or perpendicular form. The
fame holds of chiaro-/cura and colour, where mafs muft fup-
port mafs. .

The painter, fpeaking to the eye, fhould, in the choice of
his fubjeét, be careful that it admits images ftriking and

rand: it fhould burft on the fpeGtator like an unexpected
al of thunder. The horfes in the pictures of Rubens add
much to the dignity, as do alfo his fine light and fhade.
As in an epic poem, there fhould be but one action admitted
in our picture: it fhould be an entire, and above all, a great
one, and require no further aids to its illuftration than what
is contained in the picture ;—it ought to-explain the hiflory,
not the hiftory the painting. As we are not confined to the
mere letter of the ftory, we may ufe any means confiftent
with probability to illaftrate our bigs 3 as we once faw in *
a drawing of a triumph, where the artilt, to fhow the caufe
was love, decorated a car and the fhields with fuch objects
as were fymbols of that paffion; and, further, to fhow it was
connected with Thefeus and the Amazons, in the tablet of
‘an arch reprefenied that hero’s battle with thofe heroines:
but enough | an ingenious mind will find a thoufand ways
of difplaying itfelf.

~ ‘Two aétions or points of time fhould never be admitted in
one picture. M. Angelo, in the Capella Seftini, has repre-
fented Adam an e eating the fruit, and expelled the gar-
_ den, in the famé’piece! Raphael’s Peter in prifon, aud de-

livery, can hardly be called one.
Jt muft be obvious that the parts. of each figure fhould
agree

~——aied -

Obfervations on the Zodiac at Dendera, Loy

ree fo as to produce a whole: for inflance, a thin face
fhould not be united with fat hands. The fame unity is ne-
cellary between the figure and its attire, which fhould fuit
the degree and character of the perfon as well as be adapted
fo the age and fex.

We cannot do better than conclude this paper in the words

‘of fir Jofhua:—‘* My advice is this: keep your attention

fixed on the higher excellencies. If you compafs them and
compafs nothing more, you are ftill in the firft clafs. We
may regret the innumerable beauties which you may want:
you may be imperfect, but fill you will be an imperfect per-
fon of the higheft order.’”’ That great man in another place,
fpeaking of * the well-grounded painter, fays, ‘as his pre-
eminence depends not upon a trick, he is free from the pain-
ful fufpicions of a juggler, who lives in perpetual fear left
his trick fhould be difcovered.”

XVIII. Obfervations on the Zodiac at Dendera. By the
Rev, Samuzgn Henvey, FS. A.*

As the report of C. Fourrier concerning this zodiac and
its high antiquity bas made a deep impreflion on the minds
of many, and the argument thence drawn bas been deemed
of great weight, in oppofition to the Mofaic records and re-
ih religion, I fend you the following obfervations, with
the hope that they may reach thofe who otherwife might not
fee them, and have their effect upon a large clafs of readers,
who may have too lightly acceded to Fourrier’s conclufion.
Denon, {peaking of this zodiac as clearly proving the pro-

- found knowledge of the antient Egyptians in aftronomy, men-

tions the ruins which contain it, and are extani but twenty
minutes ride from Dendera (antiently Tentyra), known at
prefent under the Arabic name of Berbe. . Concerning the
etymology of this term, various opinions have been offered 3
but that by the learned De Sacy is moft generally admitted.
He conjeétured it to have been derived from Il and LPYEI,
the temple.

_ Notwithftanding this conjecture was affented to by Mi-
chaelis, Wahl, dnd Zoega, it has been oppofed by Hartmann,
who contends that Berba fignifies a pyramid or obeli/k.
Though fupported in this by Schultens, the interpretation
refts in part on a conjecture of Keifke, who for Barabi fub-
ftituted Barami, which, howeyer, in Arabic is plural; ang

* Printed, with the author’s corre€tions, from the Monthly Magazine.

708 Ob/ervations on the Zodiac at Dendera.

on the perfuafion that in Edrifi the defcription of Berba was
more fuitable Noda ia than temples. M. de Sacy replies,
with confiderable force, that Schultens would have done
more juftice to Michaelis, if, inftead of indulging conjecture,
he had opened fome Arabic defcription of Egypt; for ex-
ample, Macrizi’s, where he would have found inftances that
the term could not fignify pyramids. Accordingly, a paflage
3s cited from that author which refers to the very place,
é< Of the number of Berba is that of Dendera, which is a
wonderful edifice. It has 180 windows; each day the fun
enters by one of thefe windows, and on the next by the fol-
lowing, till at length it reaches the laft, and then returns ina
contrary direétion.”” Wanfleb (Nouvelle Relation en Forme
de Journal dun Voyage fait en Egypte,) defcribes Dendera
as the fite of a wonderful temple of the antient Egyptians—
dune grandeur et d'une hauteur DEMESURE'E § and vifible
at two leagues diftance. He alfo, applying the account of
Macrizi, and confidering the windows as double, makes them
to be as many as there are degrees in the zodiac; fo that the
fun, rifing each day in a different degree, throws his rays
through a different window, till, by, thus completing his
courfe, he finifhes that of the year. For this reafon, it is
added, the temple is regarded as wonderful. '

Taking thefe defcriptions with the other compartments
on the ceilings, given by Denon, one inference, drawn by
M. Fourrier, will be readily admitted, which is, that the
ftate of the heavens they exhibit, correfponds with the date
of the building, It remains then to determine, from the
zodiac in queftion, what this date was. Denon, on his fe-
cond vifit, thus defcribes the temple :—‘* I went to the ruins,
and this time took poffeflion of them in the plenitude of re-
pofe. I was firft of all delighted to find that my enthufiaftic
admiration of the great temple was not an illufion produced
by the novelty of its appearance, fince, after having feen all
the other Egyptian monunients, this {till appeared the moft
‘perfect in its execution, and conftructed at the happie# pe-
riod of the arts and fciences; EVERY VHING IN IT is /a-
boured, is interefling, is important. It would be neceflary
to draw the whole in its moft minute detail, to poffefs our-
felves of all that is worth carrying away.”

The date of 15,000 years before the birth of Chnift feems
but ill to agree with this account, when contrafied with the
ordinary remains of human efforts, and the uniform effect of °
human experience. The monuments of remote ages are more
remarkable for theirtude bulk than elaborate workmanfhip; _
but, if this be of the time affigned, it. follows that, in re

united

al

Obfervations onthe Zodiac at Dendera, 169

united opinions of Denon and.Fourrier, 15,000 years before
Chrift was the happiefl period of the arts and fciences. So
much for their joint decifion !

Taking, however, this calculation independently of the
ftructure itfelf, it is fairly admitted to be accurate, fo far as
it is founded on equinoéial preceffions ; but, referving difeuf-
fions on this head for a work fhortly to be publifhed *, it
will be fufficient to obferve that T had thence fixed the age of
this zodiac to the very year and day before ‘the infcription
afcertaining them was known, and which has not, even yet,
been explained.

_ The plate given from Denon f reprefents the zodiac in two

compartments, as it exifts on the oppofite plat-bands of the
portico of the temple. The two large figures that embrace
the whole, he fuppofes, reprefent the year; and the winged
emblem before their mouth, eternity, or elfe the, paflage of
the fun to the folftices. The difk, at the joining of the thighs
of the upper figure, he pronounces to be the fun, whence pro-
ceeds a etl of light that falls upon the head of Ifis, which
reprefents either the earth or the moon. ‘ The fun,”’ he con-
tinues, “ fituated in the fign Cancer, may perhaps fhow the
period of the ereétion of the temple, whilft the ficures joined
to the fizns may mean the fixed ftars, and thofe in the boats
the revolving bodies, the planets, and the comets.” After
offering thefe conjectures, this modett artift, under a convic-
tion oF their importance, refigns to others all further deve-
lopment.

Inftead of adopting what Denon has conjeCtured, it will
be proper to confider the zodiac anew. Accordingly, the
female form bent over either divifion, is ungueftionably the
Ifis, which by Horapollo is determined:to be the year. The
winged globe, according to Macrobius, is the fun commen-
cing his courte. ‘The veil on the head of the Ifis is that myf-
terious one which the famous infcription affirms no mortal
had ever withdrawn. Qn the upper bend or fhoulder of the
lower figure are eight lines or units, denoting that the fun,
at the cardinal points of the year, is in the eighth degree of

.°* A/Dilquifition on the Date, affigned by Fourrier, Commiffioner of
the Sciences and Arts in Egypt, tothe antient Zodiac there found: whence
the extraordinary Darknefs recorded by Phliegon, and that by the Hifto-
rians of China, in the Reign of Quamvu, are identified with the Dark-~
nefs at our Lord’s Crucifixion; the Difcordance between the Eclipfe noted
by Ptolemy, as feen at Arbela and Carthage, is accounted for; the further
Defideratum for afcertaining Longitude, required by the Board at Paris,
in their Report on Biirg’s lables, fupplied; and thence, in Reference to
the Prophecy of Balaam, the Birth of Chrift is fixed,
4 Sce Plate 1V,

the

110 Otfervations on the Zodiaé at Dendera:
the fign; for fo it is ated to have been by Manilius at the”
time of the Julian reform, and fuch was, according to Co-
lumella, the adju(tment of the Metonic cycle, compared with
the tables of Hipparchus. The four ftars, of eight rays each,
are the dow-ftar, which governed the Egyptian year, and,
being eight nyonths vifible in the upper hemifphere, had a
month afligned to each ray, as the fun has twelve rays to’
defignate the months of his courfe Thele four ftars here.
fignify a quadrennium, when, in ihe Roman year, an addi-
tional, or biffextile day, was added to the 365 days, which.
conftituted the Egyptian. Beneath are twelve other units,’
as making, in the biffextile year, the folar to exceed the lunar
twelve days inftead of eleven. The little circle, with wings,’
on the. breaft of Ifis, marks a new but fubordinate proceffion.
of the fun’s courfe, after the quadrennium has been com-
pleted. The waving lines extending along the figure are the
Egyptian hieroglyphic for flowing water; while the line of
ftars—each miarking, by its fix rays, as many portions of
time, and, with the fquare comprifing them, the fquare of
that numbér—feverally indicates four times fix hours, or a day.
Thefe, amounting to feventy-nine, exprefs two months orluna-
tions, and twenty days over, which correfpond to the two
lunar months added by Numa to the Roman year; .and, with
the twelve days allowed as above, compenfate for the differ-
ence between the ordinary lunar year and the folar biffextile,
while eight days, anfwering to the fun’s advancement in the
fign, complete the given number. From the bend of the leg
downward, five days are fo difpofed as to fhow the five fup-
plementary days above twelve months, of thirty days each,
that conftitute the Egyptian year. This is evident from the
ornie/s beetle annexed, which was, among the Egyptians,
an eftablifhed hieroglyphic for a month of thirty days. The
three {tars on the band furrounding the Jegs, with the four
on the fhoulder, fymbolizing conjointly feven years, ‘give
feventy-feven days as the difference between lunar and folar
time, and thus reprefent at once the fixty-feven days which
the year, by the reform of Julius, had gone back, with the
ten days between the winter folftice and the firft of January,
or fix days with which he lengthened the months in one part
of the year, and four in the other. ;
Having recourfe to the [fis of the upper divifion, it will be
found, that, inflead of eight units on the fhoulder, fhe exhi-
bits but feven, whereas the laft of the four fiars beneath them
wants two of its rays, and the units which follow ate not
twelve but eleven. To account for thefe variations, let 1t be

obferved, that, before. the Julian reform, the Roman year
being

Objervations on the Zodiac at Dendera. Int

being Junar, a month of twenty-two and twenty-three days
alternately, named Mercedonius, was inferted after the 23d
of February, to adjuft the lunar reckoning to folar; but, as
in the year of the Julian reform, the twenty-three days were
included, there would of courfe be one day’s advance on the
calendar computation, which would leave but feven days by
the lunar account for the fun’s place in the fign; whence the
eleven units below would anfwer to the ordinary differences
between the lunar year and the folar; whilft the two rays,
deficient in the fourth of the ftars, would point out the com-
mencement of the lunar year at Rome on the 1ft of March,
and the folar of Julius on the rit of January; or, in other
words, would correfpond to the augmentation of the year,
computed backward, which Numa had made. The ftars in
fquares, as before, defienatine days, which, to the bend of
the lez, amount to fixty-feven, anfwer to the beginning
of the year gone back by the Julian computation, while the
feven in addition correfpond to the fun’s place in the fign,
which, with the five fupplementary days round the legs,
make the twelve days in the laft year of lunar intercalation,
and, as the four divifions between them fhow, are coincident
again with a quadrennium.

Perfectly congruent with the whole is the pyramidal figure,
having a globe or fun at its top. It confifts of eleven grada-
tions, which anfwer to the eleven days between the folar and
lunar year, and the ninety-nine divifions upon it difcriminate
the ninety-nine days from the winter folftice, by which
Julius adjufted his reform, to the commencement of the
Roman year on the 1ft of April. Between, however, the
- Roman rft of March and the 1{t of April a month was left
out, or, in other words, had gone back a fign. This is here
expreffed by the recefs of Cancer from the zodiac, and agrees
with Virgil’s commencement of the year with Taurus :

Candidus auratis aferi¢ qoum cornibus annum

Taurus—
the precife time of which is defined by what immediately
Follows :
et adver‘o cedens Canis occidit aftro.
If, now, the fetting of the dog-ftar be placed, according to
Petau, on the fourth of the kalends of May, and the fixty-
feven days which the Roman year had gone back at the Julian
reform, thence reckoned, we come to the 26h of February,
or 1ft of Thoth, at the commencement of the wra of Nabo-
naffar, which was that likewife of the Egyptian year. The
changes in the Roman year having varied its forth, in refpect,

to its length, as well as the number of its months, and the

days

412 Odfervations on the Zodiac at Denderés

days in them, it had accordingly receded 1wo lunar mtonthes
and eight. days over, making in the whole fixty-feven, an

fo fell on the 27th of April, or day of the dog-ftar’s fetting,
whence the 28th of March would be the firft of Aries; but
as, according to Hipparchus, compared with Meton and
Manilius, Julius Cefar’s year placed the fun in the eighth
day of the fign, thefe eight days allowed, will fix the be-
ginning of Aries at the vernal equinox, and 21ft of March.

The anomalies of the Roman year being fettled by the

year of Nabonaffar, or the Egyptian, it becomes: evident,
from the pyramidal figure, with the fun on its fummit and
the cavern beneath, fignifying the vacant interlunar cave of
the moon ; that the horns of the Pan, fymbolizing the hori-
zontal beams of the dog-ftar, or completion of the canicular
year, are placed on the common boundary of the eighth and
third gradation, or day, in thé eleven, which indicate’ the
difference between lunar and folar time, or 365 and 354, to
diflinguith the eight days for the excefs beyond, the two Juna-
tions, and the three other days correfponding to the differ-
ence of the Roman lunar year, ending atthe 23d of Febru-
ary, and the year of Nabonaflar beginning on February 26,
which was the firft of Thoth by Egyptian reckoning.

The bandages round the head of the Pan exprefs the fame,
with other notes of diftinGtion; for, whilft the uppermoft
fold has eight points correfponding to eight days, as before,
the fecond exhibits five units, to denote the five Egyptian
fupplementary days, which, with the five points between
them, indicate ten days, as correfponding with the winter
folftice, December 21, whence Julius commenced his re-
form, and the 1{t of January, or his new year’s date.

But as, under this reform, the Egyptian year corrected the
Roman, fo the Roman year, thus correéted, was made by
Auguftus the ftandard of the Egyptian; for, as that confifted
only of twelve months, of thirty days each, with five days
in addition, its commencement receded one day on every
quadrennium ; confequently, from the year of Nabonaflar,

and that of the reform of Auguftus, by Julian reckoning,

fixty-four days twelve hours (the year of Nabonafflar, which

was the Egyptian, beginning at noon, according to the canon

of Ptolemy), will fhow that the firft of Thoth, five interced-
ing days being allowed between the Julian correétion, taken
as beginning from 707 of Rome, and that of Auguftus, efta-
blifhed in 725, the biffextile four days twelve hours (or,
reckoned from midnight, five days), had varied from the 21ft
of June, or fummer folftitial noon, to the agth of Auguft,
three in the mgrning, at which time Auguftus had fixed Be

7 or

Odbfervations on the Zodiac at Dendera. 113"

for fixty-four days twelve hours and four’days twelve hours’
making fixty-nine days, and exceeding ‘the fixty-feven days
of Julius by two, Auguftus intercalated between the year 709
of Rome} when Julius’s reform was completed, and his own,
fixteen years after, one day every third year in{tead of every
fourth; and fo, inftead of four biffextile days, fix were in-
ferted. Between three in the morning, when the dog-ftar’
rofe, and twelve at noon, when the fun was on the meridian,
were nine hours to complete the canonical day; thefe are
accordingly expreffed by as many lines on the laft fold of the
bandage winding round the forehead of the Pan.

Having then found, by thefe difcriminations on the zodiac,
the opening of the year, from the rife of Taurus, at the fet-
ting of the dog-ftar, which is exemplified by the folar circle
in a crefcent on the bull’s neck, it will be feen that the Thoth
thence proceeding is reprefented as a bull in a boat (for the
heavenly bodies, which were the Egyptian divinities, were
held to perform their revolutions in this manner), and as it
has been feen-from the ftar deprived of two rays on the
fhoulder of the upper Ifis, as well as from the two months
difference between the year of Romulus and Numa’s, that
the fun’s place had been altered two figns, the third boat or
month proceeds from Gemini to Cancer: accordingly, the
foremoft figure in it reprefents a prieft taking auguries from
the rife of the ftar, whilft the other is evidently Aquarius, or
the overpowering of the Nile, at the apparent new moon of
Cancer. But Cancer withdrawing from the zodiac, the over-
flow falls in with Leo; and here, accordingly, Harpocrates
appears as on the day anfwering to biffextile, which is alfo
intimated to belong to that year by the fix leaves on the head
of Aquarius, or the Nile, This being fuppreffed in the Ecyp-
tian kalendar, makes Cancer and Leo run into each other,
or confounds the laft day of one with the other’s firft. The
figure preceding Leo has the ftar of five rays, which, indi-
cating five months, marks Leo as the fifth fign, whilft the
ferpent, rifing from under his feet, exhibits the Nilotic year
thence beginning, as does the ferpent behind the Harpo-
crates, with his head ereéted from the fourth fold, a qua-
drennium. The rifing and fetting dog-ftar follow, as thus
correfponding in refpeét to fixed and moveable time. From
the overflow of the Nile, in the fign Leo, we are brought on
to the commencement of the year in Virgo. This is ex-
preffed by the torch with two flames, followed by a prieft
taking auguries at the year’s beginning, which the bull’s
head, whofe horns fymbolize the apparent new moon, and
flar of five rays above them, fufficiently evince. This alfo

Vou. XIV. No, 54, H does

134 Oljervations. on thé Zodiac at Derdera.

does the hawk, or revivifcence of nature, with a dog’s head,
and the two units above the fame ftar. , The two figures with
ftars, to intimate the five months between the rifing and fet-
ting Dog, introduce Libra? The pedeftal beneath the feale,
with the fun! on it, and a fitting figure, as if watching its
fhadow, under the index of the equinoétial balance, together
with the fun behind, and the other attendant figures, denote
the Thoth, or new year’s day, beginning from that fign
whilft the fourteen articulations in the tail of the dog will be
found to agree with the fourteenth year of the folar eycle,
concurrent with the firft lunar, when the fun entered, Seorpio.
The hieroglyphics next fucceeding, characterize again the
beginning of the year, for fuch are the hawk, crowned with
the lotus; the wolf, facred to the fun ; and the ceraftes, nifing
from anoar. The figures of the rifing and fetting ftar are
intelligible as before. We now come to Sagittarius, an hie-
roglyphic, compofed of a human body, with a bifrontal head
of a man and a lion; the Nilotic plant, which indicates the
overflow, proceeding from the veil under which both are
united. The arrow on the bow is the firft beam of the year,
whil{t the cheft, fore-legs, and body to the wing, belong to
Pegafus, or the horfe of the morning. The hind parts of
the wolf complete the reference to the new moon of Thoth,
commencing from the dawn, The two divifions on the wing
ferve to exprefs the diftinétion of the lunar and folar differ-
ence, which anfwers to the eleven feathers, whilft the twelve
intercalations between the wing and tail of the wolf, on
which a raven is feated, agree with the obtrufion of the
lunar intercalation on the common form of the folar year.
Over the wolf’s tail is a ftar of five rays, pointing at the di-
ftance between the moveable and fixed Thoth, whilft the
prieft, under the mafk of a hawk, the fymbol of a com-
mencing year, immediately follows, and, with an arrow, or
firft beam of the rifing ftar, flops the further progrefs of the
bull, which, to exprefs the moving Thoth, has an hind-leg
joined to his head. This fymbol, indeed, with the two next.

that follow, is a certain key to the whole, inafmuch as the
diftinétly mark the fixing of the firft of Thoth, the dog hold-
- ing the bull’s leg by a chain of nine links, ending with the
ar of five rays as before, whilft five of thefe ftars, f{urround-
ing the Taurine fymbol, decide their eftablithed import.
The one between the horns intimates the original rife at the
firft of April in the Roman lunar year, at the apparent new
moon, that is, the moon on its fecond day, to which add:
the intercalary month Mercedonius, and the difference is
obtained of the fun’s entrance on the fign, April 20, which.
» accords

Obfervations on the Zodiac at Dendera. rig

accords with the Roman commencement of the year on the
Palilia.. Hence, Aries is again found on the 21{t of March,
In perfect congruity with this’ is the chain of nine links an-
nexed to the ftar. For, as the fidereal revolutions in a year,
from meridian to meridian, are 366 days, there will confe-
quehtly be a day gained by fidereal reckoning: hence, as the
fun enters capricorn on the 22d of December, at noon, thefe
nine days afeertain the difference between that time and the
noon bodice 1ft of January, and thus account for the differ-
ence of ten days by the kalendar of Julius when he reformed
the Roman year.

Having then found, in this zodiac, the key to the reforms
of the Roman year, we have alfo the clue to that of the
Egyptian, introduced by Auguftus in the year of Rome 725,
correfponding to the yéar of Nabonaffar 720, and making the
difference of biffextiles fix Egyptian months, or 180 days ; but
thefe carried back from the 29th of \uguft, or fixed Thoth,
go to the moveable Thoth on the 26th of February. Thus, |
then, have we the two Thoths, before and behind Capricorn,
and thefe 180 days, from the fun’s entrance into Capricorn, |
with the four biflextiles between the reform of Julius and
Auguttus, fall in with the fummer folftice on the 21ft of
June.

But it will be remembered that one of the dog-ftars on the
fhioulder of Ifis was defective in two rays, and that Numa
augmented by two months the Roman year: if, in retrocef-
fion from Capricorn, thefe two months be cut off, we are
ftopped at the 21ft of Auguft, and thence, eight days allowed
for the fun’s advance in the fign, we are brought again to the
29th. To this month Auguttus gave his name, and Capri-
corn was his appropriate fymbol. Suetonius relates of him,
that, on confulting in his youth Theogenes, the mathema-
tician of Apollonia, when the circumftances of bis birth were
made known, Theogenes rofe, furprifed, and adored him.
The reafon of this conduét [ fhall elfewhere explain; but
here it will be proper to obferve, that, on the celebrated
gem of this emperor’s deification, the fign Capricorn is
placed in a circle, with the dog-ftar behind, which, as five
only of its rays can be feen, the others fupprefled, will accord
with the difference between the 1f of January and April,
reckoned one way, and, as Auguftus was born on the 23d
of September, adding the difference between lunar and folar
time (the Roman year being then lunar), to the rft of dena
in the other. The abfent three rays being thus accounte
for, it will be obvious that the remaining five relate to the
diftance between the 23d of September and the 1yth of Fes
willie, Hz bruary,

116 Odfervations on the Zodiac at Dendera.

bruary, to which the four biffextile days again included bes
tween the Julian and Auguftan reform, came to the 23d,
when the Roman lunar. year was intercalated; and again,
from the 1gth day of February; the eight days in the fign
reach that of the 1ft of Thoth, the year being biffextile, and
the excefs of fidereal days, from noon to noon, allowed.

It remains to obferve, that, in adjufting the Roman mode
of dating to the Egyptian, there is a nominal difference:of:
three years, which will be found to be but nominal upon:
comparing the canon of Ptolemy. Hence'what, in Romam
reckoning after the reform of the kalendar, appears to be the
722d year of the city, contrafied with’ Egyptian time, will
fall into the 725th: now, as Auguftus was in his thirty-firft
year, when he fixed the 1ft of Thoth, in the 725th year of
Rome, and made this his ff? year in Egypt, the two years
from that of Antony preceding were confidered as fupprefled.
This the annexed table will fhow: pilt

ifEra of Au- Firft of Thoth fixed to the zothl

Yeerof Romie guftus at Alex-|Dates of thejof Auguft, and, in biffextile
Seen the 37 andria, from {Roman Em- |years, to the 30th. .

f April the fixed newtpire from The afterifks mark the biffex-
es ae ae moon of Thoth./Coins. tile.

Se

The date commencing from
722 A Antony and New Rome.

Battle of Aétium on the sth
723 * of Thoth. Alexandria taken in
the month Mefori.

The death of Cleopatra, and
724 I begininng of the Czfars, after-
ward ftyled of Auguftus, in Egypt.

The years of Auguftus began to}
925 2 B be ftricken at Alexandria on coins

oe

_ The beginning of the zra o
726 3 y the Augufti at Rome, from the
|kalends of January, A. U. 727.

Thus, then, as Auguftus is ftated to have been born in the
year of Rome 691, when the Roman year is referred to
Egyptian reckoning, it will be feen that, in Roman com-
putation, his 31ft year fell into this year of reform. In perfeét
confiftence with this, and all that. has been adduced, is an -
infcription on the fouthern portal of the very temple in which
this zodiac exifts, and which, though hitherto wnapplied,
is given by Denon. It is rendered by Mr. Aikin thus: ~

~ © On account of the emperor Ceefar, god, the fon a Ju-
bata : ter,

Memorandums, Hints, Precepts, and Recipes, ec. 117

fiter, the deliverer,. when Publius Octavius being governor,
Marcus Claudius Pofthumus commander in chief, and ‘Try-
phon general, the deputies of the metropolis confecrated, in
virtue of the law, the Propyleum to Ifis, the greateft of the
goddeffes, and to the affociated gods of the temple, in the
gift year of Cefar.”” Here the infcription breaks off, but,
in the Greek, the two words @QYO TEBALTHI follow. |
For thefe the French tranflator unaccountably fubttitutes—
Le College des Prétres 4 ? Imperatrice, whereas it fimply fig-:
nifies on the facred Thoth.

Tt will now fuffice to add, that the nineteen boats under the
zodiac exhibit the nineteen years of the Metonic cycle; and
to afk, Where now are the 15,000 years before Chrifl of the
commiffioner Fourrier ?

é

XIX. Memorandums, Hints, Precepts, and Recipes, for
the Ufe of Artifis, Manufaéturers, and others; including
various fhort Proceffes either new or little known*,

{Continued from Vol. xi. p. 149. ]
Cements for Derly/bire Spar and other Stones.
I, A CEMENT for this purpofe may be made with about

feven or eight parts of refin and one of bees wax melted to-
gether, with a fmall quantity of plaifter of Paris. If it is
wifhed to make the cement fill up the place of any fmall
chips that may have been loft, the quantity of plaifter mutt
be increafed a little. When the ingredients are well mixed,
and the whole is nearly culd, the mals fhould be well kneaded
together. The pieces of {par that are to be joined muft be
heated until they will melt the cement, and then prefled to-
gether, fome of the cement being previoufly interpofed.

II. Melted fulphur applied to fragments of ftones, pre-
vioufly heated (by placing them before a fire) to at leaft the
melting point of fylphur—and then joined with the fulphur,
between, makes a pretty firm and durable joining.

Little deficiencies in the ftone, as chips out of corners, &c.
may alfo be filled up with melted fulphur in which fome of
the powder of the ftone has been mixed,—Heat the {tone

firft.

* Communications of praétical approved recipes and ufeful hints are
requetted from our correfpondents. We take this opportunity of thanking
Mefits. Gill, Pepys, an.t other friends, for their fayours in this way.

$ H 3 Temporary

118 Memorandums, Hints, Precepts, and Recipes,

Temporary Cements, €8c.

Workmen are often at a lofs for fuch a cement as will
hold firmly till they have no further occafion for it, and yet
be eafily parted when it is neceflary 5 as in fixing glafs plates
to blocks to be ground for optical purpofes, joining metallic
plates to be turned in a Jathe, &c. For fuch purpofes a ce-
ment compoled of the following ingredients will be found to
anfwer well :

III. To four ounces of refin and 1-4th of an ounce of bees
wax mielted together, add four ounces of whitening (wafhed
carbonate of lime or chalk) made previoufly red hot. The
whitening fhould be put in while yet hot, that it may not
have time to imbibe moifture from the atmofphere. This
makes a good cement for holding optical glafles on the end
of a maundril while grinding, or for fimilar purpofes.

To cement plates of metal to the chucks of a lathe in order
to turn them, the chuck fhould be heated, which is com-
monly done, by directing the flame of a candle upon it urged
by a blow-pipe; the metal fhould alfo be heated in the fame
manner until they will melt the cement applied to them.
The pieces, being then placed in contaé&, are adjufted cen-
trally while the cement cools, either by holding a pointed
ftick. in a fmall hole previoufly made in the centre of the
plate by a prick punch, or by preffing a piece of wood late-
rally again{t it. When cold it will be held firm enough,
by means of the cement, to bear being turned, and may be
difengaged at any time by again heating it.

IV. Pitch, refin, and a very fmall quantity of tallow,
melted together, and thickened by ftirring in dry brick-duft,
is employed by chafers of gold and filver articles to fupport
and hold their work.

This mixture forms a cheap cement ufeful for many pur-
pofes, as fixing fmall fteel articles on the blocks deftined to
hold them for polifhing, and is much ufed at Birmingham.
The proportions of the ingredients depend on the heat of the
weather and the particular purpofe in view. In winter, 4
larger portion of tallow is neceffary than in fummer. ey

V. Shell-lac is a very {trong cement for holding metals,
glafs, or precious ftones, while cutting, turning, or grinding
them. The metal, &c. fhould be warmed to melt it. ‘

For fafiening ruby cylinders in watches and fimilar deli-
cate purpofes, ihell-lac is alfo very excellent. ;

Memorandum.—Bees wax mixed with a little colcotha
(red oxide of iron) makes a good polifhing tool for ge 3

: ule

for the Upe of Artifts, Manufalurers, Fé. TI9

uife a little finely-wathed coleothar mixed with water for the
cutting material, applied between the tool and the lens.

fe VI. White of Eggs
mixed. up with a little quicklime (or abit of chalk burnt ina
common fire and pounded).makes a pretty good ¢ement for

glafs and porcelain... It is. not, abfolutely, neceflary that the
chalk be burnt, though. it is generally ufed fo.

Gum Arabic Cements:

VII. Gum arabic diffolved in as fmall a quantity of water
as may be, and diluted to a proper confiftence with gin or
any proof fpirit, forms avery ufeful cement for all purpofes
where gum water is commonly ufed, the fpint preferving it
from becoming putrefcent. As the fpirit evaporates, more
fhould be added. It fhould be ftirred and mixed together at
the time of ufing. 2. If plaifter of Paris be added to gum
water, it makes a cement ufeful to ladies in filligree works.

VILL, Gum ammoniac added to the folution of gum arabic
in proof fpirits very much improves the cement. It anfwers
very well for joining broken glafs and porcelain articles of
ornament.

IX. 4 fine tranfparent Glue.

Shreds or parings of vellum or parchment, boiled for a
fufficient length of time in foft water, diffolve at laft into a
very tranfparent glue. White leather, that is, fkins dreffed
with alum inftead of being tanned, will anfwer the fame end.

Lfinglafs Cements,

X. A ufeful cement is made of this fubftance by either
diffolving it in any proof fpirit by heat, or by adding to it,
when diffolved in water, an equal quantity of alcohol,

XI. An improved cement may be made by adding to the
ifinglafs, previous to its folution in proof ye one third

art of its weight of gam ammoniac, Expofe the mixture to
2 boiling heat until the ifinglafs and gum are diffolved, and
until a drop of the cotipofition becomes. ftiff inflantly as it
cools. It will at any future time melt with a degree of heat
little exceeding that of the human body, and, in confequence
of fo foon becoming ftiff on cooling, forms a very valuable
cement for muny purpofes, particularly for the very nice and
‘délicate one of fixing on the antennix, legs, &c. of infeéts in
cabinets of natural hiftory.

The eafy melting of this cement is no objection to its ufe
in cafes where the articles themfelves may afterwards be ex-
poled to moderate heat; for it owes this property only to the

H 4 prefence

120 © Memorandums, Hints, Precepts, and Recipes,

prefence of the alcohol, which evaporates very foon after it
has been applied. -

When ufed to join broken glafs or china, the pieces to be
joined fhould be previoufly warmed. Immerfion in hot water
will’ give them a fufficient degree of heat. Wipe’ off the
water before applying the cement, which may be laid on
with a pencil: then prefs the pieces together, binding them
with a {tring or a bit of foft wire if neceflary.

XII. Japanefe Cement, or Rice Glue.

This elegant cement is made by mixing rice flour inti-

mately with cold water, and then gently boiling it. Tt is
beautifully white, and dries almoft’tranfparent. Papers
pafted together by means of this cement will fooner fepa-
rate in their own fubftance than at the joining, which makes
it extremely ufeful in the preparation of curious paper arti-
cles, as tea-trays, ladies’ drefling boxes, and other articles
which require layers of paper to be cemented together. It
is in every refpect preferable to common pafte made with
wheat flour for almoft every purpofe to which that article
is ufually applied. It anfwers well, in particular, for patting
into books the copies of writings taken off by copying ma-
chines on unfized filver paper.
_ With this compofition, made with a comparatively {mall
quantity of water, that it may have a confifience fimilar to
plaftic clay, models, butts, ftatues, baffo-relievos, and the
like, may be formed. When dry, the articles made of it
are fufceptible of a high polifh: they are alfo very durable.

The Japanefe make quadrille-fith of this fubftance, which
fo nearly refemble thofe made of mother-of-pearl, that the
officers of our Eaft Indiamen are often impofed upon.

XIII. Glue of the Laplander:.

The bows of the Laplanders are compofed of two pieces
_of wood glued together; one of them of birch, which is
‘flexible, and the other of fir of the marfhes, which is ftrfl, in
order that the bow when bent may not break, and that when

unbent it may not bend. When thefe two pieces of wood

are bent, all the points of contact endeavour to difunite them-
felves, and to prevent this the Laplanders employ the fol-
lowing,cement :—They take the fkins of the largeft perches*,
and, having dried them, moiften them in cold water until
they are fo foft that they may be freed from the feales, which
they throw away. They,then put four or five of thefe,fkins
‘in a reim-deer’s bladder, or they wrap them up in the foft

Ir is probable eel-fkins would anfiver the fame purpofes—-Epat.

» Hh bark |

~

for ithe Ufe of Artifts, Manufaéiurers, (825 14X

bark of the birch-tree in fuch a manner that water cannot
touch them, and place them thus covered into:a pot of boils
ing water, with a ftone above them to keep them at the bot-
tom. When they have boiled about an hour they take them
from the bladder or bark, and they are then found: to be foft
and vifcous. In this ftate they employ: them for! glueing
together the two pieces’ of their bows, which they {trongly
comprefs and tie up until the glue 1s well dried. Thele.pieces
never afterwards feparate.—Tran/aétions of the ‘Academy of
Sciences at Stockholm. Bh ac

XIV. Jewellers Cement.

In fetting precious ftones, pieces are fometimes broken off
by accident. In fuch cafes they often join the pieces fo cor-
reétly, that an inexperienced eye cannot difcoyer the ftone to
have been broken. They employ for this purpofe a fmall
piece of gum-mattic applied between the fragments, which
are previoufly heated fufliciently to enable them to melt the
interpofed gum. They are then prefled together to force out
the redundant quantity of gum.

In the fame manner cameo heads, but without any ground,
made of pa{te (white enamel or coloured glafs) are often ce-
mented on a piece of real {tone to ferve them fora ground,
producing the appearance of. teal onyx, ‘from which they
can with difficulty be fometimes) diftinguithed.

Backs are alfo cemented to {tones in the fame manner, to
change their hue. ‘That is, behind a tranfparent ftone the
colour of which is withed to be altered, a thin plate of a
ftone of a different colour is cemented, which alters the co-
Jour of the refraéted light to.a mixed tint partaking of that of
both. In this cafe, the furfaces to be joined are previoufl
ground as flat and true as poffible.. They are called dow!lets.

XV. Turkey Cement for joining Metals, Glafs, &c.

The jewellers in Turkey, who are moftly Armenians, have
a curious method of ornamenting watch-cafes, and fimilar
‘things, with diamonds and other ftones, by fimply glueing
them on, . The ftone is fet in filver or gold, and the lower
part of the metal made flat, or to correfpond with the part to
which it is to be fixed; itis then warmed.gently, and the
glue applied, which is;fo very {trong that the parts never fe-
‘parate. This glue, which may be applied to many purpofes,
as it will ftrongly join bits of glafs or polithed fleel, is thus

wade: bea: 7
, Diffolve five or fix bits of maftic, as large as peas, in as
much {pirit of wine as will fuflice to render it liquid; in ane
bw 1% other

122 Mémorandums, Hints, Precepts, and Recipes,
other veffel diffolve as much ifinglafs (which has been pre?
vioufly foaken in water till it is {wollen and foft) in French
brandy orin rum, as will make two ounces, by meafure, of
ftrong glue, and add two {mall bits of gum-galbanum or am+
moniacum, which muft be rubbed or ground till they are
diffolved then mix the whole with a fufficient heat ;/ keep
it in a phial flopt,and when it is to be ufed fet it in hot
water.—Eton’s Survey of the Turki/b Empire. long
XVI. The procefs above deferibed may be fimplified by
adding the gum-ammoniac to the ifinglafs during its folution
in proof fpirit, and expofing. the, mixture to a boiling heat
until it is diffolved, when the folution of maftic in alcohol
aay be added. The gum-ammoniac previoufly diffolved
with the ifinglafs promotes the union of the maftic with the
mucilage. This cement has been tried in London, and found
to anfwer well: it ftands againft moifture.

Cements which refift Moifture.

Generally fpeaking, all cements into the compofition of
which gum-lac or maftic enters, of which we have already
given fome, poffefs this property.
~ XVII. A cement of this kind may be made by diffolving
ifinglafs in proof fpirit, to which muft afterwards be added a
folution of fhell-lac in alcohol.

XVIII. Another cement, which will alfo refift moifiure,
may be formed by melting by heat, without water, common
glue with half its weight of refin, to which mutt be added
fome red ochre to give it body it is particularly ufeful for
cementing hones to their frames.

XIX. Carpenters employ a cement in framing fign-boards,
&ce. to ftand the weather, which they make by adding to
a pint of well made common glue (made with water) an
eighth part of that quantity of boiled linfeed oil, dropping it
Anto the glue gently, and ftirring it all the time.

XX. White lead ground up with boiled linfeed oil to the
confiftence of paint, makes a good cement for jomning broken
porcelain, earthen ware, and glafs articles deftined to hold
water, &c. | After the cement 1s applied, between the pieces
they fhould be preffed home to each other as clofe as poffible,
The clofer the better; nor need any fears be entertained that
enough of cement will not be left in the joint; for the thin-
neft film that can be interpofed will hold firmer than a thicker
one would, The articles fhould remain undifturbed for two
or three months, and before ufing them the cement flicking
6n the outfide of the joint fhould be carefully feraped off with

a knife.
XXI. A

for the Ufe of Artifls, Manufafurers, 8c. 123
OK Ta Combe bee hardens under Water.

_Mr..Gad, in the 32d volume of the Memoirs of the Aca-
demy of Stockholm, fates, that if clay and calves (oxide) of
iron be plentifully mixed with oil, they will form a mafs
which will harden even under water.

XXII. 4 Glue infoluble in Water.

Leather-dreflers or glovers glue, that of fith, and that pre-
pared with linfeed oil, cerufe, and red lead, which cements
pretty ftrongly glafs, ftone, and wood, {till leave room to
wifh for one of a ftronger quality. :

An excellent glue may be procured from cheefe. Take
fkim-milk cheefe, free it from the rind, cut it in flices, and
boil it in warm water, ftirring it with a fpoon until it be
reduced to a firong glue which does pot incorporate with
water. Then throw away the warm water, pour cold water
over the glue, and knead it afterwards in warm water, fub-
jecting it to the fame procefs feveral times. Put the warm
glue on a grinding ftone, and knead it with quicklime until
you have a good glue. When you wihh to ule this glue you
mutt warm it: if it be employed cold it is not fo ftrong, but
it may alfo be ufed in that manner. This glue is infoluble
in water as foon as it is dry, and it becomes fo in forty-eight
hours after it has been applied. It may be ufed for glueing
wood, and for cementing marble and: broken ftone, and
earthen ware. The joining can fearcely be difcovered.

Baits alfo for catching fifh may be made of it. Fifth are
very fond of it, and it refifts water. Boerhaave obferved that
no menftruum diffolved cheefe, not even aqua-regia.—Tran/~
aétions of the Academy of Sciences at Stockholm.

XXUT. A Cement that will fland againft boiling Water,
and even bear a conjderable Preffure of Steam.

Tn joining the flanches of iron cylinders and other parts of

hydraulic and fteam-engines, great inconvenience is often
experienced from the want of a durable cement.
' Boiled linfeed oil, litharge, red and white lead, mixed to-
gether to a proper confifience, and applied on-each fide of
a piece of flannel, previoufly thaped to fit the joint, and then
interpofed between the pieces before they are brought home
(as the workmen. term it), to their place by the ferews.or other
faftenings employed, make a clofe and durable joint.

The quantities, of the ingredients may be varied without
inconvenience, only taking, care not to make. the mafs too
thin with the oil. ‘It is Tificult in many cafes inftantly to

r4 make

224 Memorandums, Hints, Precepts, and Recipes, ec.

make a good fitting of large pieces of irom work, which ren-
ders it neceffary fometimes to join and feparate the pieces
repeatedly before a proper adjuftment is obtained. When
this is expected, the white lead ought to predominate in the
mixture, as it dries much flower than the red. A workman,
Knowing this faét, can be at little lofs in exercifing his own
difcretion in regulating the quantities, It, 1s fafeft to err on
the fide of the white lead, as the durability of the cement
is no way injured thereby, only a longer time is required for
it to dry and harden.

When the fittings will not admit cafily of fo thick a fub-
fiance as flannel being interpofed, linen may be fubftituted,
or even paper or thin pafteboard; the only reafon for em-
ploying any thing of the kind being the convenience of
handling.

This cement anfwers well alfo for joining broken flones
however large. Cifterns built of fquare ftones, put together
with this cement, will never leak or want any repairs. In
this cafe the ftones need not be entirely bedded in it, an inch
or even lefs of the edges that are to lie next the water need
only be fo treated: the reft of the joint may be filled with
good lime.

XXIV. Another Cement that will fiand the A€tion of boiling
Water and Steam.

This cement, which is preferable even to the former for
fteam-engines, is prepared as follows: .

Take 2 ounces of fal-ammoniac, 1 ounce of flowers of
fulphur, and 16 ounces of caft-iron filings or borings. Mix
all well together by rubbing them in a mortar, and keep the
powder dry.

When the cement is wanted. for ufe, take one part of the
above powder and twenty parts of clean iron borings or filings,
and blend them intimately by grinding them in a mortar.
Wet the compound with water, and, when brought to a con-
venient confiftence, apply it to the joints with a wooden or
blunt iron fpatula.

By a play of affinities, which thofe who are at all acquainted
with chemiftry will be at no lofs to comprehend, a degree of
ation and reaction takes place among the ingredients, and
between them and the iron furfaces, which at laft caufes the
whole to unite as one mafs. In faét, after a time, the
mixture and the furfaces of the flanches become a {pecies of
pyrites (holding a very large proportion of iron), all the parts
of which cohere ftrongly together, |

Abel XXV, An-

New Method of making Cement for Terracess8c, 124

XXV. Another Cement of the fame Kind.

Take two parts flowers of fulphur and one part fal-ammo-
aaa and mix them together with a little water into a {tiff
alte.
_, Take alfo, borings or turnings of ,caft iron in the ftate in
which they are commonly found in works where boring and
turning are carried on, viz. mixed with fand, and fift them
finely to get rid of the groffer particles.
hen the cement is wanted for ufe, diffolve a portion of
the above pafte in urine, or in water rendered flightly acidu-
lous, and to the folution add a quantity of the fifted borings.
This mixture, {pread upon or betwecn flanches of iron pipes,
or put into the interftices of other parts of iron work, will in
a little time become as hard as a ftone.

XXVI. Blood Cement.

A cement often ufed by copperfmiths to lay over the
rivets and edges of the fhects of copper in large boilers, to
ferve as an additional fecurity to the joinings, and to fecure
cocks, &c. from leaking, is made by mixing pounded quick-
lime with ox’s blood. It muft be applied frefh made, as it
foon gets fo hard as to be unfit for ufe.

We believe, if the properties of this cement were duly in-
veltigated, it would be found ufeful for many purpofes to
which it has never been yet applied. It is extremely cheap,
and very durable.

[To be continued occafionally. J

XX. On a new Method of making Cement for Terraces; and
the Uje of liquid Pitch to render them impermeable to Water,
and fecure from the Attacks of Froft. By Casimir
PUYMAURIN.

I SHALL not fpeak of the nature of the different lime-
Sie hitherto known, as they have been fully deferibed
y various authors ; I fhall only obferve, that a cement ought
to be hard, folid, and impermeable, To obtain a hard and
folid cement it has been neceffary to employ different bodies
which, by their aggregation with lime, diffolved in water,
) abtart the fuperabundant moifture, and furnifh to
the particles of lime diffufed throughout the cement the car-
bonic acid neceffary for rendering it folid, and regenerating it

into calcareous earth.
Vitrified

$86 = News Method of making Cement for Terraces; \.

Vitrified lava, natural and artificial puzzolanay the fcoriz
ef furnaces, pounded bricks, boue-athes, have been the bafes
of all the cements hitherto made, and they have been ob- |
tzined more or lefs folid. Cements compofed in this manner
have been attended with perfect fuccefs in the fouthern parts
of Europe, little expofed to rain: ‘they do not abforb the ex- :
terior moifture, and the froft has not power to dilate their
pores or to deftroy their aggregation. Ia

The cements of Italy, Africa, Spain, and other warm coun-
tries, unite all thofe qualities which can be defired by the moft
exact obferver; but in our rainy countries, expofed to very
ftrong frofts, cements oucht to poflefs a more’effential qua-
lity than hardnefs or folidity, that is to fay, smpermeability.
Cements compofed of porous bodies cannot poffefs this qua-
lity: being bard, and having their ereateft-folidity during
fummer, the rains of autumn gradualJy penetrate to their in-
terior parts, to reduce to powder that mafs which a little be-
fore had the appearance of the greateft hardnefs,

Fhe inventors of the moft celebrated cements have feen
their experiments fail becaufe they neglected this effential
guality. The interpofition of a fat body was long ago em-

loyed. Pliny and Vitruvius recommend the thick part of
oil, and oil itfelf; but thefe bodies employed alone can never
anfwer the intended purpofe, Oil with the lime of cement
forms a faponaceous body foluble in water: the thick part of
oil contains a very large quantity of mucilage, which water
diffolves or carries off.

To preferve the bottoms of veffels, and to render them im-
permeable to water, refinous bodies have been employed, and
particularly liquid pitch. I have thought that my cement
fhould be covered with boiling pitch, as this refinous body
penetrates its pores and renders it impermeable to water.
One inconvenience, however, appeared in the ule of pitch,
which is, its property of becoming foft during the beat of
fummer. This inconvenience I remedied by befprinkling
the pitch with powder of lime: the lime combines with the
pitch, and forms on the cement an exterior ftratum of new
cement refembling the famous cement of thé Romans called
maltha. ch ; :

All the merit of my labour confifts merely in having firft
employed, for preferving cements and rendering them im-
permeable, a fat body capable of penetrating them, of filling
up their pores, and of being infoluble in water,

I fhall here give the method which I employ for making
my cement; but I muft firft obferve, that there. cannot be
one general method of compofing cements, unlefs yaar “=

an

and the Ufe of Liquid Pitch. i 127

and fand were cvesy where of the fame quality. The ob-
ferver, therefore, muft examine the nature of the compofition
of the lime he employs, and particularly the purity of the
fand and filiceous matters: he may’then vary the dofes of
the materials of his cement as may be neceffary.

Every method of making cement requires, in -general, that
the puzzolana, pounded brick, and fcoriz, be reduced to
fine powder and fifted: This precaution is neceffary for
cement which is not to be covered with a refinous body: its
furface thereby becomes fmoother and more compa, and it
is lefs liable to be penetrated by moifture. But this advan-
tage is more than compenfated by the fiffures and cracks oc-
cafioned by the fhrinking of the cement. This fhrinking
does not take place in cement made according to my method,
becaufe [ employ. all the matters hard, coarfely pounded, and
in fragments of the fize of a grain of wheat, and often as large
as peas. Thefe fragments broken in this manner prefent
a great number of angles aud cavities into which the calca-
reous part penetrates, and thus forms a kind of connected
chain, which prevents thofe cracks and fiffures fo prejudicial
to cement. The lime which I employed was made from
hard and white limettone of the hill of Cazeres, in the de-
partment of the Upper Garonne: this lime diffolves with a
fort of ebullition and a great heat, and after its folution forms
a white pafte without any mixture of gravelly parts: it is fuf-
ceptible of fwallowing, as the mafons here term it, a great
deal of fand and other hard matters, but it bas lefs ftrength
in the open air than meagre lime, which being made from
marly {tone contains im its compofition a great many
baked and vitrified argillaceous matters, which give it gyeat
firength when expofed to the open air and to water. ‘This
lime, called in the country chau de Bourret, requires little
fand, becaufe the calcined and vitrified earthy parts which it
contains form with it already an intimate mixture, or a kind’
of cement: this lime, therefore, diffolved in water, acquires
in a little tume the hardnefs of ftone.

The lime I employed then was perfe@ly pure, without any
internal mixture of heterogeneous parts, but which has no
great folidity when expofed to the open air.

‘I found that a fifth part of lime was fufficient to give to
ooo tsa that connecting quality neceflary to envelop all the
vitrified and filiceous parts of a calcareous ftratum, and, con-
fequently, to give it the greatett folidity. Such is the proces
T employed to form on a roof, confiructed for two hundred
years, the joifis of which were at a great diftance from each
other, y terrace of forty {quare fathoms, which ftill sa
. an

x28 0 New Method of making Cement for Terraces 5

and has'withftood four fevere winters and.our feorching fume.
mers.)

One precaution which I did not take, and which embar-
rafled me a good deal, was to pound the limeftone before it
was employed. The ftone diffolves in water; but fome ftones
being lefs calcined than others, their nucleus does not diffolve,
and only becomes penetrated with moifture. When thefe
are blended with the, gravel and filiceous matters employed,
at the end of fome days the cement blifters and fplits into
fmall fragments, and bits of the lime which have not been
diffolved are found in the ftate of lime flaked in the open air.

Take two meafures of river pebbles well wafhed, or frag-
ments of brick of the fize of a nut; two of tiles and iron
feales coarfely pounded, one of river fand perfeétly well
wathed, and a meafure of the lime of Cazeres, juft from the
kiln, and pounded.

Form a circle with the fand, and throw into the hollow the
lime which has been flaked, taking care to mix it thoroughly:
when the lime is well diluted leave it in that ftate for three
hours in order that the whole lime may be diffolved; then
mix with it gradually the river pebbles, the iron feales, the
tiles, and the fand. This mortar muft then be worked for
half an hour, that every filiceous {tone and fragment of tile
may be well incorporated *. .

Such is the manner in which I prepare cement. There
are two methods of employing it; either above a pavement
of brick, or below.it. The former appears to be the moft
folid during the firft year, while the other fuffers the rain
water to filter through it, but at the end of a certain time it
acquires the moft perfect folidity.

As time deftroys the timber on which the mortar is placed,
when a terrace is intended to be made on a floor it muft be
coarfely covered with fand and clay: when this covering is
dry, another, compofed of mortar and pretty fat fand, muft
be placed over it: there is no neceffity for cutting the bricks,
and the upper furface muft be rough or notched with a chifel..
This pavement muft have an inclination fufficient to make
the water run off.

In the month of July, when the two coverings are very
dry, the cement compofed in the above manner muft be ap-

hed in bands of two feet in breadth ; two workmen are
fufficient. ‘this ftratum of cement ought to be from two

* When the cement is almoft finifhed throw over it about a bufhel of
quicklime in powder, The mortar then becomes very difficult to be ftirred.
Or two pints of milk of lime are then to be added, which will penetrate
the cement in every part, ;

inches:

and the Ufe of Liquid Pitch. 129°

inches and a half to three in thicknefs; the covering on’
which it is placed ought to be moiftened with milk of quick-
lime; and the cement mutt be preffed down clofely with’
the trowel, taking care to beat it with the fharp edge of that
inftrument. It is fmoothed by the back of the trowel flightly
moifiened, The furface of the cement muft be again prefled
down, to bury the coarfer parts and render the whole fmooth.
When the firft band is finifhed the workman proceeds to a
fecond, and the two bands muft be carefully united to pre-
vent their feparation.

This cement foon dries, and at the end of an hour can fuf-
tain a ftrong preffure. It muft, however, be left feven or
eight days; after which the furface of it is to be flightly
moiftened, and then preffed down and fmoothed by means
of flat ftones in the fame manner as marble is polifhed. This
lat precaution is effentially neceffary, and the folidity of the
cement will depend on the care with which it has been per-
formed. When the terrace has been conftruéted in this
manner, the aggregation of the cement becomes ftronger,
and its pores are fmaller and lefs numerous.

In order that the cement may fucceed perfectly, it mutt
be made during the great heats of July, that the fuperabun-
dant water may evaporate, and that it may be perfeétly dry
before the autumnal rains. At the end of Augult, boil pitch,
fuch as that ufed for fhips, and fpread it over the cement by
means of large brufhes. As this coating would render the '
cement not fit to be touched during fummer, this inconve-
nience may be remedied in the following manner :—Take
lime, flaked in the open air and reduced to fine powder, and,
having {prinkled it over the pitch, remove, by means ofa
broom, the fuperfluous part of the lime which does not ad--
here toit. This lime, by combining with the pitch, will
form with it a very thin ftratum of cement fimilar to the
maltha of the Romans. At the-beginning of October a fe-
cond firatom of pitch and lime muft be laid on.

The fecond method of employing the cement:is to place it’
immediately over the ftratum of brick and clay, and then to
cover it with a pavement of brick, mortar, and fand. I have
two terraces, fifteen fathoms in length and one and a half in
breadth, which appear to me to have the greateft folidity.
lab are not fo beautiful as thofe where the cement covers
the brick; but they can ftand every kind of friction or pref-
fure.

After making a ftratum of clay and fand, fpread over it a
firatum of cement four inches in thicknefs, well beaten, and

Vou. XIV. No. 54. I add

130. New Method of making Cement for Terraces, Se.

add pebbles fomewhat larger than thofe employed in the pte-
ceeding cement, and increafe the dofe of lime in proportion:
‘the cement muf then be beaten with clubs like thofe ufed for
fmoothing the walks in the neighbourhood of Paris. Tt is
then to be left to dry for a month, after which the furface of
it mult be moiftened with milk of lime; and the bricks are
to be placed with good lime and fand.

It is not neceffary that thefe bricks fhould be ground. I
have obferved that, by cutting, their ftrength is leffened, as
it deftroys their upper half-vitrified furface: nothing then.
remains below but an earthy furface, which is foon pene-
trated by moifture, and which is eafily deftroyed by froft.
Care mutt he taken to fill up the joints with good mortar,
which muic be prefféd in and fmoothed by the trowel, and
then pitened.

Terraces conftructed in this manner fuffer the water for
fome time to filter through them in fmall quantity. This
water charged with calcareous particles {tops up tlie pores of
the cement; no more filtration takes place: and terraces of
this kind have the greateft folidity, and are exceedingly cheap.
This cement may be employed with advantage for the interior
of apartments; it alfo may fupply the place of pavements of
cut bricks, and cofts two-thirds lefs.

It muft be f{pread over a pavement of rough bricks, or
bricks picked with an inftrument, to the thicknefs of an inch
or nine lines. ‘The pebbles may be omitted, and their place
fupplied by fragments of tiles and tron {cales coarfely pound-
ed: itis then to be preffed down and fmoothed with flat
ftones, but before it is painted it muft be fuffered to dry for
amonth. It is painted and waxed im the fame manner as
brick pavement.

Such are the details of the cement I have employed, and
which has been attended with complete fuccefs. But I thal!
here repeat, that the dofes mutt be varied according to the
ereater or lefs purity of the lime and of the other matters.
employed; and the application of pitch is merely to prevent
the infiltration ef water, and the defiruétion of the cement.
by froft.

oem

ergy

XXI. 4 fhort Vieew of the Craniognomic Sy/tem of Dr. Garr,

of Vienna. By L. Bosanus, M.D. Member of the Me-

ical Societies of Jena and Paris, and of the Society of the
Obfervers of Man.

[Continued from p. $4-]
13. Organ of the Inflin& of exalting onefelf.

HE organ in the middle of the interior edge of the pa-
rietals at the upper middle part, and a little towards the po-
fterior of the head, gives us a true idea of the difficulties which
oppofe the refearches of Dr. Gall, and at the fame time fur-
nifhes us with a ftriking example of the happy opinions of
this great obferver. :

He found this organ well expanded in the chamois goat,
and {till more in the bouquetin; he obferved the fame thin
in feveral men diftinguifhed for their pride. It was difficult
‘to collect all thefe obfervations into one point of view. But
when he confidered that the chamois goat inhabits the moft
elevated peaks of the mountains; that the bouquetin always
endeavours to afcend higher; and that pride, when atten-
tively examined, is only a defire of being fuperior to others 5
he was perfuaded that it muft be this organ which produces
thefe effects different in appearance, and he confidered it as
the organ of the inftiné&t of exalting onefelf.

The head of the proud man, carried upwards and back-
wards, tends ftill more to confirm this opinion.

{It appears to us that the picture of the proud man, cone
trafted with that of the humble and modeft, renders the truth
of this idea fiill more ftriking. In the former, every thing is
directed upwards: the hair is highly frizzled; the head is
elevated ; the eye-brows are arched upwards; the eye-lids
are raifed; the {houldets are ftraight; he walks on tip-toe
and fooks om every thing around as beneath him. In the
Jatter the hair baugs down naturally; the eye-brows, eye-
lids, and head, are lowered; the body and knees are flightly
bent: in a word, every thing denotes fubmiffion, and that
he has no with of being above others.]

14. Organ of the Love of Glory.
Tf this organ is more extended on the fides, it forms that of
the love of glory; an inclination very analogous to pride.
15. Organ of the Love of Truth.
The fun&tion of the organ which fhows itelf at the pofte-

- fior and fuperior angle of the parietals is not entirely fixed by

La Dr,

132 Short View of the Craniognomic Sy/lem

Dr. Gall: he, however, has fome reafons for confidering this
angle as the feat of the organ of the love of truth, but he has.
not yet collected a fufficient number of faéts to be fully con-
vinced of it.

(We find fome difficulty in being perfuaded that there is
any truth in regard to this function aferibed by Dr. Gall to
the laft-mentioned organ. It appears to us that an organ
placed in the middle of thofe with which animals as well as
men are provided, cannot be deftined to a faculty fuch as
truth, which belongs only to the latter.

*However, the cafe with this faculty is perhaps the fame as:
with that of pride, which in animals undergoes a great mo-
dification: and we confefs we have feen two men, one of
whom, diftinguifhed by great veracity, was furnifhed with:
this organ in the higheft degree ; whereas the other, who had
a moft extraordimary propenfity to falfehood, was fo deftitute
of it, that his head at that place inftead of a cavity exhibited
a protuberance. |

In the anterior and inferior part of the frontal bone Dr.
Gall has found feveral ergans the funtion of which is very
important.

During his _firft refearches.he confidered them as the or=-
gans of the different kinds of memory ; but finding afterwards
that they were not only reproduétive but alfo productive, he
was. induced to confider them as the organs of a particular
fenfe, and to eftablifh on this obfervation the opinion, that
memory in general is only the reprodu€tive action of all the
organs: imagination, on the other hand, is their produétive
action.

The fpontaneous movement of the man who endeavours
to recollect fomething, feems to have a relation to thefe or-
gans. He carries his hand, as if involuntarily, to the bafe
of the forehead. This action, though not perceived by the
perfon who performs it, is howevertconftant, and is never
confounded with that already mentioned in {peaking of the
organ of courage.

16. Organ of the Senfe of Locality.

The organ of the fenfe of locality 6ccupics the anterior part
of the frontal bone which correfponds to the protuberances
above the orbits (profuberantie /upra-orbitales) ; it generally
accompanies thofe crania which are diftinguifhed by large
frontal finuses, and which always exhibit im the infide a -ca-
vity correfponding to an eminence of the brain.

When it acts reprodudiively it conflitutes what we call the
memory of locality (aemoria lJocalis); on the other hi

. when

.

of Dr. Gall, of Vienna. 133

when it acts productively it determines the combinations of
new localities.

It is this organ which direéts the bload-hound, in which it
is very {triking: it exifts in all the birds of paffage : it invites
them to change their place of refidence; to undertake diftant
voyages; and to find again their former place of habitation :
the ftork and fwallow are provided with‘it in an eminent de-
gree, and thefe are the animals which migrate to the greatett
diftance from our countries. Men furnifhed with it are ob-
erved to have a firong remembrance of places, and a defire
for travelling: it is therefore always found in able landfkip
painters.

‘* A general who arranges his army, and who with one
look muft obferve all the localities of the country which it
occupies, cannot difpenfe with this organ.’ Of this, the
great Frederick was a ftriking example. At an advanced
age this organ is one of thofe which gradually decreafe : it is
known alfo that memory of every kind, and 1magination, are
loft as a man grows old: the frontal finuses are then increafed
interiorly ; the action of the brain no longer oppofes fo much
refiftance to their expanfion.

17. Organ of the Senfe of Faés (Senfus Rerum),

The fenfe of facts has its correfponding organ‘ in the infe-
rior and anterior part. of the frontal .bone, in the middle of
and below the preceding: it a¢ts productively and reproduc-
tively, and in the latter cafe it fupplies‘a remembrance of
faéts and of things. — Be,

It is an organ very neceflary for education and inftruction,
which abfolutely require that one fhould remember things
paft: in old age it is fubject to. the fame changes as the pre-
ceding. ‘3 hats apes

Among animals the elephant is particularly diftinguithed
by the expanfion of this organ. This animal remembers,
with the greateft accuracy, every, civcumftance and faét.which
has any relation to it. TPO |

Among men we have found this organ not only in thofe
who had a great deal of memory in regard to facts and things,
but alfo in thofe who might be called fyfiematic heads, who
arranged faéts in order, and deduced conclufions from them ;
and in thofe who had a ready conception, and who diflin-
guifhed themfelves by a defire of knowing every thing, It
even appears to ug that the operation of combining facts to
deduce from ‘them a refult is one of the principal actions 0,
this organ: the elephant, at leaft, which keeps in its trank
water to befprinkle, as it paffes, the perfon who offended it
be, 13 the

334 A foort View of the Cramognomic Sy/tem

the preceding evening, arranges feveral facts, and deduces
from them a refult which is a real logical conclufion; and
we are acquainted with no other organ in the elephant to,
which this action can be referred.

The automatous motion of a man who perceives that he
has acted wrong, feems to fupport thefe conjeéjures: he
ftrikes the middle of the forehead with his hand.

18. The Organ of Painting and of the Senfe for Colours.

The organ of the fenfe for colours or of painting occupies
the anterior part of the frontal bone below the orbit. Dr,
Gall has obferved this organ in all painters of great talents.

“* As this difcovery did not reach us till lately, we have
been able to colleét only a imal! number of obfervations :
we have, however, obferved it in fome individuals; and it is
very apparent in the head-of Raphael, in the National Mu-
feum, No, 57.”

19. Organ of the Senfe for Numbers.

The organ which correfponds to the inferior and exterior
part of the frontal bone near the zygomatic apophyfis of that
bone has the funtion of the fenfe of numbers: it exifts in
men who have a retentive memory for numbers, and in arith
meticians, who perform with great facility the combinations
of calculation: it exifts in that kind of pie which bas the
faculty of counting as far as nine; the only inflance known
among animals.

«« We had occafion to obferve this organ on the head of a
blind perfon at the Quinze-Vingts, who is diflinguifhed by
his arithmetical talents; and Dr. Gall has in his poffeffion the
bults of { eral men which furnith very inftrudctive examples.”

20. Organ of the mufical Senfe.

Below this organ is that of the mufical fenfe, or fenfe of
founds. It aéts in the fame manner as the other organs,
productively and’ reproduétively ; it gives a memory for recol-
leéting founds; it facilitates new combinations of mufical
compofitions; it incites the birds to’ fing: it a€&ts in thofe
which are learning to fpeak, and whofe language is founded
only on this remembrance of founds.

It is abfolutely wanting in animals which have no mufical
fenfe ; it is very apparent in the parrot and ftarling; and the
great muficians Gluck, Mozart, Haydn, and Pleyel, furnith
ftriking examples of it,

a1. Organ of the Senfe for Mechanics.

In the lateral and infesior part of the frontal bone is placed
the organ of the fenfe for mechanics. The caftor, wigh panes

trutts

of Dr. Gall, of Vienna. 136

ftructs edifices, is endowed with it in an eminent degree: it
exifts in the field-moufe, and in birds which build their nefts
with a great deal of art: it is found in men who have a ta-
lent the mechanical obje&ts, who confiruét with eafe any
kind of machine, and who diftinguifh themfelves in the dif-
ferent arts that require manual labour. Though it be very
difficult to judge of the exiftence of this organ when it is
only moderately expanded, * becaufe the temporo-maxillary
muf{cle covers this part of the cranium, it is very eminent if
the faculty exifts in a fuperior degree; and it is then one of

thofe organs refpe&ting which there can be the leaft doubt.”

22. Organ of verbal Memory.

In the interior of the orbit at the bottom of the fuperior
part is the organ of verbal memory; it may be obferved at
the time of its expanfion by the-influence it has on the pofi-
tion of the globe of the eve, which it always pufhes forwards,
and more or lefs without the orbit.

Perfons provided with this organ eafily retain words in
their memory. Dr. Gall, when young, remarked this fa-
culty in feveral of his fchoolfellows, who were not only diftin-
guifhed for this talent, but alfo for very protuberant eyes,
This was the firft obfervation, which afterwards gave a direc-
tion to all his refearches. A great many obfervations in re-

gard to this organ have fince confirmed the truth of its exift-

€nce and of its funétion.

«©

23. Organ of the Senfe for Languages,

The organ at the exterior and fuperior part of the orbit is
called by Dr. Gall the organ of the fenfe for languages. Its
prefence has a confiderable influence on the pofition of the
globe of the eye; it forees it downwards and towards the
nofe, and increafes its diftance from the fuperior edge of the
orbit: in animals it does not exift, and therefore in the Jatter
the globe of the cye is directed more towards the exterior
and lateral part of the orbit.

[ts expanfion is always accompanied with a diftinguithed
talent for languages: it is very ftriking in great philologues ;
and though it be difficult to judge externally of its exiftence,
we have obferved that it has never efcaped the acute eye of
Dr. Gall, and that, in regard to this point, he has never once
been deceived,

24. Organ of Memery for Perfons.

The funétion of the organ at the upper and interior part of
the orbit has not yet been difcovered by Dr. Gall; but feveral
14 obfervations

136 A fhort View of the Craniognomic Sy/ftem

obfervations on man and animals, fuch as the dog and horfe,
have induced him to fuppofe it to be the organ of memory
for perfons. Its expanfion, like that of the preceding, mutt
have an influence on the pofition of the eye; it muft con-
tribute to remove it from the upper edge of the orbit, and to
puth it towards the exterior and lateral part, if an equal ex-
panfion of the preceding organ does not counterbalance its
effect,

25. Organ of Liberality.

The organ of liberality is placed in the anterior part of the
frontal bone, above thofe of the fenfe of locality and of the
fenfe for painting (16 and 18), and clofe to the mufical
fenfe (20): a very great expanfion of it accompanies prodi-
gality: it is wanting in mifers, and in thefe this part of the
frontal bone exhibits a cavity. Dr. Gall has in his poffeffion
numerous examples of it.

«© The proximity of the organ of mufic and of the fenfe
for painting (18 and 2.) feems often to favour the expanfion
of that of liberality ; and this, perhaps, is one of the reafons
why we fo often find prodigals among thofe men who excel
by their talents for thefe two arts.”

We conftantly obferve, that the older a man grows the
more niggardly he becomes: at an advanced age, therefore,
the diminution of this organ is fo firiking, that it fometimes
gives rife to a very confiderable extenfion of the frontal
finuses.

26. Organ of the Spirit of Comparifon.

The organ above the fenfe for facts in the middle of the
forehead is defiined for a faculty which Dr. Gall calls. the
comparative f{pirit (jrdicium compurativum). \t forms an
oblong eminence, and is found in men who in fpeaking have
-a ready command ot figures or tropes; who are not at a lofs
fpr expreflions ; who relate well, and have a great deal of

loquence.

a7. Organ of the metaphyfical Spirit.

If this organ is more expanded towards the fides, fo that
it formis.a round eminence which rifes in the middle of the
forehead, it indicates a metaphyfical fpirit. Among the
butts of the antient philofopbers that of Socrates in particular
aflords one of the moft ftriking examples of this organ.
Among the modern philofophers, I fhall mention only Kant,
as one of the moft celebrated.

[{ recollect that the forehead of one of my firft fchoolfel-
lows, whom we ftyled the philofopher, on account of his at-

. . tachment

«dlr

of Dr. Gall, of Vienna. 137

tachment to the abftract feiences, exhibited a very fenfible
expantion of this organ. ]
28. Organ of the Spirit of Ob/fervation.

The organ of the fpirit of obfervation extends over the
whole anterior part of the frontal bone, and its expanfion
brings the forehead nearer, in a greater or lefs degree, to the
vertical fine. It is found in particular in the crania of the
obfervers of all ages. The celebrated phyfician Frank is en-

dowed with it in an eminent degree; and Dr. Gall himfelf
is evidently furnithed with it, ;
29. Organ of the Spirit of Satire.

The organ of the {pirit for fatire and wit (qwitz of the
Germans, and facetie of the French,) correfponds to the
frontal protuberances. Dr. Gall obferved feveral examples
which prove the truth of this opinion; and we have never
found it to fail.

30. Organ of Mildnefs.

The organ of mildnefs is fituated in the middle of the fore-
head above that of the fpirit of comparifon (26). It forms
that oblong elevation which is conftantly found in the heads
of Chrift and Mary painted by Raphael and Coreggio, and
greatly contributes to give them an engaging character of
mildnefs and benevolence: it always accompanies the crania
of men naturally mild, and is wanting in thofe who are ma-
levolent and revengeful *.

Among animals, the roe-buck, hind, pigeon, &c. are pro-
vided with it: on the other hana, it is wanting in animals of

rey, fuch as the eagle, fiarling, tiger, fox, &c. The frontal
Boue, then, inftead of being arched and elevated, is depretled
and hollow.

31. Organ of Theatrical Talents.

A very ftriking enlargement of the fummit of the frontal
bone arifes from the expanfion of the organ for reprefenting
fentimends by geftures, or of theatrical talents.

** Dr, Gall has collected many obfervations which prove
the truth of this opinion; and it cannot fail to be obferved
by thofe who examine with attention the heads of the great
a¢tors of the different theatres of Paris.”

[We think we have obferved alfo that this organ is par-
ticularly expanded in the deaf and dumb; and this we afcribe
to the neceflity which thefe perfons are under of keeping it in

* That mildnels which refults from the principles of morality is not

here meant, but that which exifts by inftinél, without being the confe-
quence of moral reflection,

continual

138 A Short View of the Craniognomic Syflem.

eontinual aétion—an exercife which muft neceffarily favour
the improvement of it.]

32. Organ of Theofophia.

The organ of theofophia occupies the moft elevated part of
the frontal bone. All the reprefentations of the old faints
preferved to us afford very inftruétive examples ; and if there
be one deftitute of this charater, it is certain that it is alfo
void of expreffion.

An exceffive expanfion of it is obferved in religious fana-
tics, and in men become religious by fuperftition. It is the
feat of this organ which, according to Dr. Gall, has induced
all nations to confider their gods as above them in an ele-
vated place in the heavens. When we confider, indeed, this
object with a philofophic eye, there is no more reafon for
placing the deity above the globe than below it,

33. Organ of Perfeverance.

The laft of the organs hitherto found by Dr. Gall is that
of perfeverance, conftancy, and firmnefs of character: it is
fituated at the anterior and fuperior part of the parietals in the
middle of the head. When it exifts in excefs it gives obfti-
nacy ; and inconfiftency is the confequence of a want of it.

** In regard to thofe parts of the cranium in which Dr.
Gall bas not yet found organs, it is probable that his further
refearches will fome day enable him to difcover more; and
the work he intends to publifh will furnifh us with further
details on the fubject. It belongs therefore to him to con-
vince us, in an incontrovertible manner, of the truth of bis
fyftem, a detail of which cannot be fatisfactory in a treatife
fo incomplete.”

We find it neceffary to remark alfo, that all the organs
here enumerated cannot be diftinétly perceived but in indi-
yiduals who poffefs any faculty in an eminent degree; and
that it is impoffible to judge properly of a moderate talent,
when its organ is too much confounded with the neighbour-
ing ones, ©

‘© In regard to the objeétions made to the fyftem of Dr.
Gall, that it Jedds immediately to materialifm, we do not fee
the philofophical reafons on which it is founded. Even if
we fuppofe organs for the interior faculties, the immenfe di-
ftance between thought and matter ftill remains the fame ;
objects of fo heterogeneous a nature are not {nfceptible of being
claffed together. Befides, the will ftill remains entire: it is
it which ought to counterbalance the action of the organs ;
and the paffions ought to be-reftrained by morality.

XXII. Letter

{ 139 )

XXII. Letter from Count Mornozzo to C. Lacerepz,
Senator and Member of the French National Inflitute, om
an Ichneumon brought from Egypt*.

In the middle of April 1802, C. Aimet, chef de batailion
in the corps of engineers, brought to Rome a young ichneus
mon which he had caught in Egypt. I took the. earliett
opportunity of examining it; and, as I made fome-very ine
terefting obfervations in regard to the natural hiftory of this
animal, I communicate them to you with pleafure.

The Greeks and the Romans called it the achneumon: it
is the mangoujte of Buffon, and the mus Pharaonis of Pro-
fper Alpinus. It is a pretty animal, about the fize of a cat,
with a long tail; its hair is rough and of confiderable length;
it cannot be compared to any thing better than. the briftles
of the wild boar. It is radiated tranfverfely with three co-
Jours, viz. grayifh white, fawn or raffet colour, and black.
Each hair has five or fix tranfverfe rings, like the quills of the
porcupine : the length of thefe hairs from the body is an inch
or an inch anda half; they are fhorter on the tail, and ip
particular at the head, which gives to the animal a neat ap-

earance,

The head, and particularly the muzzle, are very fmall;
it has beautiful teeth like thofe of thedog; two canine, fix
incifive teeth, and eight grinders in each mandible, maki
in the whole thirty-two. It has fmall ears of a brown ¢o- |
Jour without hair; they adhere to the head like thofe of apes.
Its eyes are {mall and lively. An obfervation which I made -
in regard to the eyes will be mentioned hereafter.

Its colour varies a great deal according to the place im
which it is viewed. When obferved towards the fide of the
head it appears to be grayifh black; when looked at behind,
jt appears to be reddifh. “The legs, and particularly thofe - .
before, are fhort: it has five toes on each foot, four before and
one {maller behind, The two middle toes on eath foot are-
longer. The nails are black, like thofe of the d

The young ichneumon is very familiar and domeftie: it.
is fond of being carefled ; it is much afraid of cold; and
though the temperature of Rome is very mild, it was gratified
by having a covering now and then thrown over it; fome-
times even a chaffing-difh was placed near it. Very often it
Jies down in a round form ona chair or on the bed, which

* Fiom the Journal de Phyfique, Mgfi. or, ats» 1%
at

140 On an Ichneimon brought from Egypt.

it leaps upon with great agility, and conceals, its head be-
Hiween its thighs to keep tilelf warm.

“4 "Fhis “individual is a female: it has below its parts of fex
a large bag, which has been defcribed by all naturalifts : it is
afferted that during the great heats it opens this bag in order

_ to cool itfelf.- Jonfton gives a very good defcription of this
conduit, which is ‘as follows:—*‘* Meatum denique extra
foramen: excrementi peramplum, undique pilis cinétus, pu-
dendo muliebri non diffimilem, quem magno urgenti cetu
operifi folet. Hine fcriptores omnes indiferiminatim ich-
neumones-et mares et foeminas arbitrati funt *.’’ From this
conduit an odoriferous liquor diftills: the individual in quef-
tion, on the approach of a dog, opens this bag, and the dog
immediately retires: no odour however is perceived at the
time. The meafurement of the different parts, which 1 took
from the animal itfelf, is as follows :

-Whole length from the muzzle to the extre- Foot. In. Lin.
mity of the tail = = = 9 i5* 2

* Jt wanted, however, a fmall bit at the extremity of the

‘tail, which feemed to have been cut off, and which may be

‘eflimated at an inch or an inch anda halff.

Meafures in Detail,

1g ‘ Foot. In. Lin.
_ Length of the head + - * O14 Ne
Leneth.of the body - > - i eel,
" Length of the tail - - G4 MER io RH
2 ee ake yl Fotal 2 5 3
Circumference taken at the thickeft part of Foot. In. Lin,
the body - - SH ci Sao pe
‘Circumference of the muzzle below the eye oe:
Heish of the fore-legs - “c(h lO aad ie

‘*. The figure given by Buffon is very good, and has a perfect

gefemblance to the individual here defcribed. The figure of y

Aldrovandi is alfo very corre&t. The cafe, however, is not
the fame with thofé of Jonfton and Profper Alpinus.

- In regard to the defcription which Buffon has given of the

amoenhe: it is traced out with the fame pencil which has i
o well delineated the other animals: he has feparated fable

_* Jonfton Hift. Animal. quad. p, tos.

+ Kempfer, in‘the defeription which he gives of the ichneumon or
mangoutte in his Amaenitates Exotica, p- 574, fays that 1t was two feet
aod a half in length from the heag.to the extremity of the tail.

from

On an. Ichneumon brought from dig ypte:. I4fs +

from hiftory, and has defcribed its habits with great -pro=. :
priety. Two obfervations, however, which I had an op=
portunity of making, and which appear of importance, feem>
to have efcaped him. ; ,

1ft. That the animal has a kind of interior eye-lid, which.
paffes over the globe of the eye as in nocturnal birds; but
with this difference, that in the eye of owls this membrane.
rifes and falls in a direétion which I would call perpendicu-
lar from the bill to the fummit of the head, while in the in-_ -
dividual in gueftion it proceeds. Jaterally from the noftrils to
the ear; which induces me to believe that the animal feeks
its prey in the night-time. By means of this interior eye- -
lid it contraéts the pupil at pleafure, and it muft then fee in
obfcurity, like the cats; but in the latter the pupil is leffened
and dilated by contraétion ;. whereas in this animal the fame
thing is effected without contraction, and, as we may fay,
by mechanical means.

2d. That the four toes of the fore- as well as hind-feet are
connected to each other by a brown membrane without hair,
fuch as that of amphibious animals. I extended its toes
and examined this membrane, which is folded backwards,
fo that when the animal walks it is not feen. This certainly
indicates that the animal fwims with great facility.

This charaéter proves that it ought to be claffed among
amphibious animals. Jonfion fays of the ichneumon:—
** Amphibium eft animal et ad Niloticas ripas commoratur.””
Aldrovandi alfo confiders it as amphibious: his words are:
* Ab ordinis ratione non effe alienum opinamur, fi poft
lutram ichneumonis hiftoriam-recenfeamus, quoniam et ipfe
inter animalia avgoiepiavra, id eft promifcua in aquis et terra
degentia, reponamur, ideoque a nonnullis lutra Agypti nun-
cupatur*.”? He quotes alfo Strabo, who is of the fame opi-
nion. * Strabo quoque hanc belluam aquatilem confiftere
videtur.”” .

However, though thefe refpectable authors have confidered
this animal as amphibious +, none of them have mentioned
the fkin on its feet, which forms a kind of fins. Ariftotle,
Pliny, and Profper Alpinus, are equally filent refpeCting it.
Though this charaéter feems very effential in the defcription
of an animal which frequents the banks of rivers; while, on
the other hand, they have carefully noticed this peculiarity in
the feet of the otter and in thofe of the caftor. After what

* Aldrovandi de quad. dig. p- 298.

+ [take the word amphibous in the fame fenfe in which it was
taken by the antients; for this term, ftriétly fpeaking, can be applied
@nly to the family of the phoce,

. has

14% On an Ichnewmon brought ran Egypt.

has been here faid, will it be afferted that this is not the cafe?
By no means ; for there is no oppofing facts.

Buffon in his defcription of this animal exclaims againft
fomenclators and generic denominations. I know that
fcience will make little progrefs when people are prejudiced
in favour of their fyftems ; but there are certain characters
fo ftriking in fome animals that no error can be committed
in claffing them. He reproaches Linneus with having
made the ichneumon at firlt a badger, then a ferret; yet it
certainly belongs to neither of thefe fpecies.

Had he obferved that fkin or fort of fins which it has on
its feet, he would certainly have claffed it among the amphi-
bious quadrupeds after the caftors and beavers, which have a
fimilar membrane between their toes. Klein calls it Juéra
Algypti*; but he does not fpeak of fins. Befides, as the
ichneumons frequent the banks of the rivers in Egypt, where
they fearch in the fand for the eggs of the crocodile, of
which they are exceedingly fond, or go in queft of thofe fer-
pents which the Nile leaves among the mud after its inun-
dations, they mutt be obliged to crofs, by {fwimming, fome
arms of the river or fome canals in order to find their prey.
For this reafon nature has provided them with fins, and the
conformation of the eye induces me to believe that they
mutt alfo fearch for their food in the night-time. To this
faé& I fhall add the decided tafte which the individual in,
queftion shas for fifh, which feems to prove that the ichnen-
mon in its wild ftate eats this food.

As this animal will foon be at Paris, you will be enabled
to examine it yourfelf, and to verify my obfervations. I have
no doubt that others will be brought from Egypt: you can
examine whether the peculiarities 1 have defcribed be com-
mon to all ichneumons, or belong only to fome families.

If this animal fhould unfortunately die before it arrives at
Paris, for it has fuffered a. great deal by the change of. cli-
mate, and thefe animals, belides, do not live to a great age,
you will fee the beautiful piéture of it which M. Aimet
caufed to be executed by M. Peter, an excellent artift in this
department, who has reprefented it with the greateft exact-
neis poifible. Two figures of it are delineated under two
points of view. M. Peter kept it at his houfe for a fortnight,
to ftudy its deportment and attitudes, in order that he might
be able to give a correct-reprefentation of it.

* De quadrup, p. 66.

XXIII, Of

a

{ 143 J

XXII. Of the State of Vapour fubfijling in the Atmofphere.
By Ricwarp Kirwan, E/g. LL.D. F.R.S. and
P.R.I. A.*

V apour or moifture in the atmofphere may fubfift in
denfe air, or in air highly rarefied: that it is found in’ the
former is well known, and that it may fubfift in the latter
appears by the obfervations of Bouguer; for he faw clouds
three or four hundred toifes above Chiromboracho, and’
confequently at the height of twenty-two thoufand five hun
dred and twenty-eight Englith feet, or 4:3 miles over the
level of the fea; a height at which in the temperature of 32°
a barometer would ftand at 12°7 inches. At fuch heights,
atid at much inferior, fince evaporation proceeds much more
quickly, it is not to be fuppofed that all the vapour fo rapidly
produced is diffolved in the ambient air, but part rifes un-
combined, as it does under an exhaufted or half-exhautted re-
céiver, and in this cxfe Mr. De Luc’s {yftem is admiffible.
This emiffion of pure vapour feems to begin at heights at
which the denfity of the air is 25, (that is, at heights at which
the barometer would ftand at twenty-five inches, and thus I
fhall in future exprefs the various denfities of air,) at leatt it
is very confiderable where the denfity is twenty. This
leads me to treat of the properties and ftate of pure invi-

‘fible vapour, namely, its {pecific heat, elafticity, and fpecific

tavity.

: The immortal Do&or Black, the father of all: difcoveries
of this kind, informed me that the vapour of water, boilmg
at 212°, that is, at 180° above the freezing point, and poffet-
fing the fame fenfible heat as the water, contains nine hun-
dred and forty times more latent beat than an equal weight
of water does heated’ to 212°, or 5-222 times more latent heat
than it does of fenfible heat, counting from the freezing
point, for 186 x 5-222 = o40 nearly. In this cafe the.
preffure or denfity of’ the atmofphere is thirty, the barometer
ftanding at the heielt of thirty inches; and with Door
Black's account the experiments of Mr. Schmidt of Gieffen
very nearly agree ; for according to him the latent heat of the
vapour of water, barometer 29°84 inches, and the heat 912°,
fe times greater than its fenfible heat above the freezing
point: now 180 X 5°33 = g5g'4t. The difference or ex-
cels in his. experiment proceeds from the preffure of the at-
._* From his paper intitled, «* Of the Variations of the Atmofphere,”

Dublin, ror,

+ Gren’s Phyfical Journal, iv. p.z1g.

DY ol mofphere

144 Of the State of Vapour

mofphere being fomewhat lower, as Mr. Watt’s experiments
rove.

‘ Mr. Watt difcovered that the latent heat of fteam dimi-
nifhed in proportion as its fenfible heat increafed, Phil. Tranf.
1784, p. 335. Now the fenfible heat offteam exceeds 180°
above the freezing point when the baromeicr ftands above
thirty inches, and lefs than 180° when the barometer ftands
lower than thirty inches, as Mr. De Luc firft difcovered, and
may be feen in Sir George Schuckburgh’s and Mr, De Luc’s
tables, Phil. Tranf, 1779, p. 375. [rom thefe I have de-
duced the following table :

Heat of boilmg| The accuracy of this table even in the
water. | lower part of the fcale is fufficiently apparent
a by the refult of the experiments of Sauffure on

ebullition on Mount Blanc ; for on that enor-
212°, mous mountain, the barometer ftanding at 16
21028 | reuch inches or 17°05 Englith, he found wa-
20852 ter to boil at the heat of 68°g93° of Reaumur,
206°73 a degree which on Geneva thermometers 1s

equal to 145°56° Englifh.—Hence we fee that
203'06 diftillation may be more advantageoufly ef-
tage fected on mountains than on plains, and at
low barometrical heights than at the greater,
yet within certain limits ; for, at heights that
195°36 furpafs, 8 or so thoufand feet, the fuel, by
reafon of the rarity of the air, is more flowly
6 confumed. Hence alfo, from the knowledge
188-46 of the degree of the heat of ebullition to two
185-864 7 Ore decimal places, the ftate of the baro-
184-36 meter above or below 212° may be infer red to
13°86 | OnE Or more decimal places. The reafon of this
176-70 rapid diminution of the heat of ebullition be-
/~" low 25, inches is evidently the diminution of
refiftance, from the diminifhed weight of the atmofphere,
which then is very fenfible: but as the cold continually pro-
duced by evaporation is then alfo very confiderable,. the ézme
neceflary to procure ebullition is longer, as Sauffure remarked
on Mount Blanc. Vol. vii. in 8vo, § 2011, p. 328. He
found the heat of ebullition barometer 16 to be 68*993 de-
grees, or in Englifh meafures barometer 17°05..185°5 of
Fabr. (counting one of Reaumur at Geneva =. 2°225, of,
Fahr.) , ai 2iso
~ Hence fince, according to Mr. Watt, the fenfible heats of
the vapours of boiling water at different barometrical heights
are as the barometrical heights reciprocally, and the {pecific
: heats

Subfifting in the Atmofpheres 148

heats of the vapours of water boiling are as the fenfible heats
reciprocally, it being known, that the fpecific heat of the va-
pour of water heated to 180 degrees above the freezing point
is 940. The fpecific or latent heat of the vapour of boiling
water, whofe fenfible heat is known, (and it may be known
by the barometrical height as fhown in the above table and
the notes) may alfo be difcovered. '

Thus the fenfible heat of the vapour of boiling water baro-
meter 30 being 180° above the freezing point (212°—32°=
180°) and the fpecific or latent heat of vapour, whofe fenfible
heat is 208°56° (that is 176°56 above 32°) as itis when the
barometer ftands at 28 inches, is 958 for ++ 176756. 180::
940°958 *. Bu TGl 2 pidt la greets

As pure invifible vapour does not in my opinion (of which
I have already ftated the grounds) exift in the atmofphere
when its denfity is higher than 25, as it is in moft of the in-
habited parts of the globe, but is always in this cafe united to
air, an inquiry into its latent heat at different temperatures
below ebullition were fuperflnous. _ But as it does exift in air
whofe denfity is 25 or lef, fince it is found in air whofe den-
fity is 12°5, it becomes neceffary to examine its latent heat in
fuch cafes, in all temperatures inferior to that of ebullition.
Now, by analogy, I apprebend this latent heat in all inferior
temperatures may thus be determined,

As the /enfible heat of ebullition, when the barometer is
at 25 or below 25, is to the datent beat of the vapour at ebul-
lition, fo is the fenfible heat of water heated to any inferior
degree above 32° to the latent heat of its vapour, multiplied
by 5°222. Thus the fenfible heat of water in ebullition baro-
meter 25 being 171°4° (= 203'4°=32°) its fpecific heat is

206
87 (= sc ) the latent heat of the vapour of water at
7

22° above congelation (that is 52° on Fahr. feale) is 657
for =: 171°4° 987 :: 22°.1:6 X 5°22 = 657. The latent
heat of vapour in fuch cafes cannot be determined by experi -
ment, on account of the admixture of atmofpheric air: we
mutt therefore refort to analogy, which in this cafe is perfect.

The latent heat of pure vapour at greater heights is more
confiderable: thus at heights, at which the barometer ftands
at 20 inches, the latent heat of vapour whofe temperature is
22° above 32°, as in the lat cafe, is 730; for the heat of
ebullition 1s 194:8°, per table, = 162°8°, above 32°: and
the latent heat of the vapour at ebullition is 1039. Now +
162'8. 1039 :: 22. 140 and 140 X 5°23 = 730.

* Hence 169206, being the product of 180° xX 940, is the common di-
vidend of all fenfible hears de/ow 180°, when ree latent heat of the vapour
is foyehe ar baromerrical heights below 30 inclics.

~ Vou. XIV, No. 54. K As

146 Of the State of Vapour

As airis cooled by the reception of moifture diffolved in it,
we mutt infer that its capacity for containing heat is in-
creafed, and hence moift air is more difficultly heated or
cooled than dry air of the fame temperature. (‘or the cold
proceeds from the abforption and not from the expulfion of
caloric.)

The elafticity or expanfive force of pure vapour has been
examined at every fifth degree of Reaumur above 0 to 110°,
by Mr. Betancourt, and may be feen in an excellent work of
Prony’s, his Architecture Hydraulique: he has by a moft in-
genious calculation interpolated the expanfions anfwering to
the intermediate degrees. But Mr. Schmidt feems to have
determined this expanfive force ftill more exactly than Betan-
court. Hence I here infert this table, adding Fahrenheit’s
for Reaumur’s degrees, and diftinguifhing the expanfions in=
terpolated by calculation from thofe aétually obferved by J.
The forces are meafured by the elevation of a mercurial co-
Jumn in inches and hundreds of a French inch*.

Reaum. Fabren. i Reaum.|° Fahren. esl
1 | 34°25° | cord at | 79-229 | rorl
a eo 03 I 32) S| Beg I'OI
3 | 3875 | co5L | 23 | 93°75 | 1192
4 [40 | cop | a4 | 86” | 1267
5 | 43°25 "Ir || 25 | 88°45 | 1°39
6 | 45°5 “T5 26 | 905 1'38 TF
7} 47°75 16 I 99 1 oare5. | 14m ©
ae Bcy 20 I 28 | 95° 1r'6or
9 | 5225 | 1252 |} 29 | 97°25 | r80t

EO PMB RORY RESO: 9} OOD ep 208
it 56°75 | 342 31 | 10:7 rca I
12 59° ie 32 |104: vi2t
33 61°25 | "44 33 T06°25 2°23
t4 63°5 “5° T | 34. 108 5 2°40
ami aie sa ga 35. }110°75 | 2°68
16 68° 61 36 | 119° 2°80 I
TA Re 69I || 37 |115°25 | 3°20
18 | 735 ao. Sa iggs | wha 5
1g 74°97 84 Wi j 39 I 19°75 3 40.
BO ths Ter | go. || 40 |122 3°64

| 80. |a12° 28

* The Paris cubic inch = r‘21 Englifh. Now the En; lifh cubic inch
of mercury when its fpecific gravity is 13°6 weighs 3443°2 Englifh grains:
therefore the Paris inch weighs 4186 Englifh grains, and t-1oth of this
inch = 418°6 grains: and r-i0o0th of this inch 41°86 grains.

Notés

fubfifimg in the Atmofphere. 147

Note.—1°. Moft of the interpolations from the 88th de-
gree to the 122nd I have myfelf inferted, as thofe calculated
by Schmidt erred too widely by his own account.—Gren’s
Phyf. Jour. iv. 272.

ado. Mr. Pigtet has alfo made a fet of curious experiments
on the elafticity of pure vapour in low temperatures. E//ais
de Phyfique, p..157. He found that a grain of warm water
i vacuo evaporates in forty minutes in the temperature of
38° Fahr. under a receiver containing 1452 Englith cubic
inches*, but that it did not diffufe itfelf equally in lefs than fix
hours, and then raifed the hygrometer from 17° to 60°, that
1S 43°5 and during this whole time the cold under the re-
ceiver was conftantly decreafing, though flowly ; which de-
creafe undoubtedly contributed to the diffufion of the va-
pour.

Mr, Schmidt has alfo made a feries of experiments upon
the dilatability of air, made as dry as poffible by expofure to
hot tartarin—an object of great importance, that had never
before been examined. This table I here infert, converting
Reaumur’s degrees into thofe of Fahr. and adding from his
formula the degrees he omitted.

Reau.] Fahren. | 'Xpanhon of Reau.} Fahren, apodan oy
one inch at 32°.}) one inch at 32°.

I | 34°25° | 10044675 79°25° | "0938175
36'°5 "0089350 815 "0982850
38°75 | "0134025 83°75 | °1027525

4 | ar "0178700 | 24 | 86° *1072200
43°25 | '0223375 | 88:25. | +1116875

45'5 "0268050, 9°°5 *ITIOI55
47°75 | °0312726 92°75 | °1206225

8 | 50° "035740 | 28 | 95° "1250909
52°25 | °0402075 97°25 | °1295557

54°5 © | °0446750 99°5 | *1340250

| 56°75 | 0491425 10°75 | *1384925
a2 | 59° 0536100 || 32 | 104° "1429600
61°25 | 0580775 106'25 | *1474275

63°5 0625450 108'5 | *1518950
65°75 | °c670125 110°75 | *1563625

16 | 68: 0714800 || 36 | 113° | *1608300
70°25 | °0759475 115°25 | *1652975

72°5 "0804150 117°5 | °1697650
74°75 | 70848825 119°75 | *174@825

Bo} 77° 0893500 || 40 | 122° °1787000
212° "3574000

Note.

* Ibid. page gr.
K2

148 Conjectures refpedting the Origin of Stones

Note —1°. Hence we fee that 1000 inches or meafures of
dry air at 37 would become 1004°4675 at 34°25 Fahr. and
at 50° would become 1017°87. Hence 1000 meafures of dry
air gain ‘985555, &c. by each degree of Fahr. above 32°
(or more compendioufly 1°9856, which is true to two decimal
places) or nearly two.

ado. We fee the fource of the difeordant refults of
D’Amontons, De Luc, Lambert, Schuckburgh, Roy, Ber-
thollet, and Monge, &c. ; for they all operated upon air more
impregnated with various degrees of moifture; befides taking
the boiling point at different barometrical heights; in the
prefent experiments it was taken at 29°841 Englifh inches.

3tio. It appears that the expanfions are as the differences of
heat above 32°, as D’Amontons, Lambert and Schuckburgh
alfo noticed; though their experiments, not being made on
perfectly dry air, could not be very exact.

[ Yo be continued. ]

XXIV. Some Conjeciures refpetting ibe Origin of Stones
which have been ubferved to fall from the Clouds. By .
Wicwitam Beaurorp, A, M.*

Ts E falling of ftorres from the clonds, a natural phzeno-
menon not generally under{tood, is by no means a novel cir-
cumftance in the hiftory of nature. “Several {tones were ob=-
ferved to fall from the clouds in Yorkfhire in 1360, m Boh
mia and Saxony in 1480, in Bohemia about 1753, in
enna in 1794, in Portugal in 1796, in Yorkfhire in England
in 1795, and near Benares in the Eaft Indies in 1798. From
an analyfis made of thcfe ftones by the French academicians
in 1768, and by the Royal Society. of London in 1802, they
are ail found fimilar in their component parts to each other,
but diffimilar to al! bodies found in mines and quarries, being
compoled principally of four kinds of fubftances: the firlt
being in the form of dark ‘grains, compofed of filex, mag-
nefia, iron, and nickel; the fecond, a kind of pyrites; the
third, metallic iron; and the fourth, a gray earthy fubflance
which feryés as a cement to the others, and with which they
were coated. From thefe compofitions the matter feems to
be of volcanic origins yet it is dificult to conceive how ftoneg
of any confiderable magnitude could be thrown at fuch a di-
fiance from any volcano as thofe found in Bohemia, Saxony,
and Britain. ‘The neareft volcanos to Britain’ are thofe of
Vefuvius, Zitna, and Hecla: a fione to be thrown into Bri-

* Communicated by the Author. Ps
tan

-obferved to fall from the Clouds. 149

tain from any of thefe, would require an impetus of between
8 and 400 miles; and, if allowance be made for the refift-
ance of the air, 1200 under the greateft range of 2400 miles 5
a force not known to exift on the earth. It is true, volcanic
afhes, when colleSted in the upper regions, will be carried by
the clouds to an amazing diftance. Bat thefe are fmall light
athes, not ftones. It is evident, therefore, if thefe fubftances
originate from volcanic afhes, they muft be formed in the
clouds, where thofe afhes, meeting with carbonic, fulphuric,
and other acids, and mixing with earthy particles drawn from
terreftrial objects, are, by the eleGtric fluid in the lightning,
precipitated from the aqueous vapours which bore them up,
and, becoming united, fall to the earth in the form of fiones ;
as in fome meafure is evinced from the flathes of light and
detonation which accompany their fall.

Subftances alfo of the fame nature may be formed in the
clouds without the affiftance of volcanic matter ; for the car-
bonie, fulphuric, and aqueous vapours, which rife from mines,

umaces, bogs, vegetables, and animals, and the fmall par-
ticles of filiceous and calcareous earths which colleét in the
clouds, are decompofed or made to aflume new arrangements
by the eleétric fire, whereby the minerals are generated and
‘united to the earths, and confequently fall in the forth of
fiones. Thus ftones, by means of elestricity, are formed in the
clouds from the ferriferous principles afcending from yoleanos,
mines, and furnaces. Britain, indeed, is too far from any
volcano to fuppofe that any quantity of volcanic matter can
be wafted by the winds to this ifland; yet it contains a num-
~ der of ferrnginous mines and furnaces employed in the ma-
nufactory of that metal; from which proceeds an immenfe
quantity of gas, containing the ferriferous matter, and fuch
matter as is generally connected with it. Befides, there is
a circumftance not generally attended to by mineralogifts —
that all mines of whatever nature contain a mineralogical at-
mofphere replete with the generic principles of the metal con-
tained in the refpective mines. That Nature, by her flow but
regular operations, is daily producing nictals from their ele-
ments, will hardly be denied ; and whether the atinofpbere of
which I {peak be produced by éxhalations from. the ingre-
dients fhe employs, or a part of, the ingredients themfelves,
the cafe will be the fame as to the’ object J have in view.
' This atmofphere has a ftrong and vifible efect on the ftones
‘and vegetables which cover the foil, efpecially that which
covers mines of iron, lead, and copper. Animal and vege-
table exuvie, and other decayed mundics, arifing frony bogs,
morafles, and dirt-hills, produce a great quantity of ciaag
K an

3 50 On Stones obferved to fall from the Clouds.

and fulphuric gafes, containing the generic principles of iron,
magnefia, and nickel, &c.: thefe, uniting with filiceous, ar-
gillaceous and calcareous earths, produce in great quantities
that fpecies of iron ore termed bog ore, and that in much
greater quantities than is generally imagined. ‘Thefe ores are
produced in Jumps from 40 to 100 lbs. and more in weight,
containing from one-fourth to one-half of pure metallic iron,
intermixed with pyrites and vitrified fub{tances refembling
elafs and petrified fhells, the inhabitants of frefh-water lakes.
Whence it is evident that a number of petrifactions and mi-
neralizations are performed by water and air aflifted by the
electric fluid alone; and a number of the operations of nature
have been attributed by philofophers to the effects of fire, and
deemed volcanic, which are the efle€ts of the aqueous and
pneumatic elements.

In order to afcertain in fome refpects the truth of this
propofition by experiment, I caufed a quantity of gas, libe-
rated from water by means of fteel-filings and vitriolic acid,
to be received in a glafs veffel, to which was added carbonic
acid from the fumes of charcoal and fulpburic gas, with the
fine duft of chalk and earth, until the whole appeared a dark
thick cloud. The eleétric fpark being then pafled through
it, a flath of light and a fmart detonation enfued. After this
operation the cloud became more tranfparent, leaving at the
bottom of the veffel a quantity of water, with a gray powder,
evidently metallic, mixed with earth. If the experiment had
been performed on a larger fcale, and the ingredients varied,
the refult might have been more decided, and the phenome-
non more accurately demonftrated.

This is a fubjeét that merits every philofophic inveftiga-
tion. The magnitude of the ftones undoubtedly depends
on the quantity of generating matter, and the height from
whence it falls; yet, how ftones of fuch a weight as that
which fell in Yorkfhire could be formed in the air, might be
a fubjeét of doubt, if the fubftance had not been found of the
fame nature as thofe which fell in Bohemia and Sienna. But
it ought to be confidered that thefe fubftances are not formed
jnflantaneous in the clouds: the conftituting matter, pre-
cipitated by the eleétric fhock, is thrown by the explofion
toa point, when, from the action of the air in falling, it
becomes enveloped in the terra cementium with which the
matter is mixed. Whence, the greater the height or range
the matter has to pafs through from the time of the eleétric
fhock, the larger will be the ftones. Mot if not all the
meteors formed in the air even at great heights probably
originate from one caufe: thofe which contain the larger

portion

Qu the Hydrometer. 15

portion of inflammable air take fire at the eleCtric fhock, and
produce thofe luminous and fiery meteors fo aftonifhing to
mankind ; while thofe which contain lefs inflammable matter,
but a greater quantity of the ferriterous principles, are formed
into fire-balls or ferruginous ftones of different magnitudes,
which defcend on the earth; whilft the more light, or thofe
which are compofed only of inflammable gafes, mount into the
upper regions of the atmofphere, where, taking fire, they fly
off in luminous vapours. ‘The height to which fome of thefe
vapours are carried before they are decompofed is amazing ;
reaching into regions where we {hould imagine the atmofphere
would not be of fufficient denfity to fuftain them. But the
natural biftory of the terreftrial atmofphere has not yet been
fully inveftigated ; nor the power and effects of ele¢tricity in
the formation of lithological, mineralogical, vegetable, and
animal fubftances ;—fubjects that demand the attention of
the moft able chemifts and fagacious philofophers.
Dublin,
Sept. 16, 1S02.

XXV. On the Hydrometer. By Wiii1aM Speer, E/q.
Supervifor and Affayer of Spirits in the Port of Dublin*.

Tue hydrometer, or areometer, as it is called, is an in-
firament which afcertains the denfity of liquids, weighing
unequal mafjes with the fame weight.

This inftrament is of great antiquity, and until lately it
was {uppofed to have been invented at the end of the fourth
century, by Hypatia, the daughter of Theon, the celebrated
mathematician of Alexandria: but M. Ufebe Salverte, in a
memoir on this fubjeét, in the Annales de Chimie, vol. xxii.
has demonftrated its having been invented by Archimedes
three hundred years before the period in which Hypatia was
horn; and the very elegant Latin defcription he gives of this
wnlirument, from an author of great antiquity, fhows that,
in the form, feveral of thofe now in ufe djfler but liule from
that of the original invention.

This inftrument, from the facility and expedition with
which it may be applied, has long been in ufe for afcertain-
ing the fpecific gravity of vasious kinds of liquids; but its
application to the particular purpofe to which it is now ufed
is comparatively of modern date.

* Exera€ted from his “¢ Enquiry into che Caufes of the Error and Irre-
gularities which take place in alcertaining the Strengtus of Spirituous
Liquors, &c. London 1%02.”

K4 Until

152 On the Hydrometer.

‘Until within a period of about forty years, the ftrengths of
fpirituous liquors were moftly afcertained by other modes,
both in Great Britain, Irelagd, and on the Continent.

Proof by oil, by agitation, by firing gunpowder, by alka-
line falts, and by glafs bubbles, has been ufed,’ but in every
eafe found defeétive ; and the hydrometer was at length re-
forted to, as an inftrument calculated to afcertain thefe
ftrengths with lefs trouble and greater accuracy.

To obtain indications of ftrengths by it correétly, how-
ever, depends on circumftances that have not, until lately,
been fufficientiy underitood or afcertained; on which account
the inftrament has been complicated in various ways, by
weights and fliding rules: thefe, in fome cafes, have rather
increafed than diminifhed its irregularity.

The object of the following inquiry is therefore to bring
into one view all the caufes of thole imperfections and irre-
gularities, and, by fo doing, to prepare the way for their
removal,

Thofe irregularities have arifen from feveral caufes. In
the firft place, when Clarke’s hydrometer was conftruéted
(forty years ago), the effects of expanfion by heat, and con-
traCtion by cold, on the f{pecific gravity of fpirituous liquors,
bad not been accurately alcertained ; nor was the diminution
of bulk by penetration (or concentration, as it is improperly
called,) well underftood.

In this ftate of ignorance of thefe effects, Clarke’s hydro-
meter was conceived to be a great improvement on that which
had been in ufe before it. Precifely the fame kind of advance
‘in improvement had been made in the Trith hydrometer, fome-
what nearly about the fame period. The duty on fpirits in
both kingdoms previous to this time was paid only on two

-denominations, viz. fingle and double fpirits; the former was
proof, or under it, and the latter all fuch as were ove, proof ;
and this difcrimination of ftrength was made either by a rude
fort of inftrument which hardly deferved the name of hydro-
meter, or by dropping oil into the: fpirit: if the oil floated,
it was called fingle; if it funk, it was double.

The prefent Lith hydrometer was adopted about two or
three years’ after Clarke’s hydrometer in’ England; both of
‘which purporting to difcriminate the increafe of firenath by
per centages *, fo as to proportion the additional rate of duty

Ms to

* As this term occurs frequently in the following eflays, and may not,
perhaps, be clearly underftood by all my readers, it may not be amils to
explain it here ;—A fpirituous liquor is faid to be ten per cent. over hy-
drometer proof when it is fo firong that one hundred gallons of er

admit

On the Hydrometer. 153

fo the relative increafe of overproof, were confidered great
improvements ; and though, from the conftruétion of Clarke’s
hydrometer, it was evident that the variations occafioned by
change of temperature were then fomewhat known; yet in
Ireland the effects of thefe variations were conceived fo im-
material, and the numerous weights attached to this inftru.
ment, the difficulty of underftanding it, the certain delay
and probability of miftake, were confidered to be fo objection-
ble, that it was deemed better to ufe,an hydrometer which
paid no regard to temperature, than to ufe one liable to fo
many other objections. The variations by the ordinary
change of temperature being, however, from one to fifteen
per cent., this defeét in the conftruction of the Irith hydro-
meter is fo manifeft, that it is prefumed it would be a wafte
of time to attempt any demonftration of its incompetency.

Although Clarke’s hydrometer has not been conftructed
without a reference to temperature, yet this has heen at-
tended to only in part; and the inftrument being otherwife
very defective, it will be neceffary to exhibit thefe defects,
in order that they may be guarded againft in fuch hydrometer
as fhall be adopted inftead of it.

Till Clarke’s hydrometer was adopted, which, from the beft
information I can obtain, took place about the year 1762,
proof ipirit was made by mixing equal portions ‘of water and
the ftrongeft {pirit which could be procured: but it being
fometimes difficult to obtain this proof f{pirit for comparifon,
fuch a mixture was made by order of the ‘honourable board
of excife; and it was found, that when fix gallons of it were
mixed with one gallon of water, a wine gallon of the mixture
weighed feven pounds thirteen ounces avoirdupoife: the board
therefore declared, that the fpirituous liquor, of which the
gallon weighed feven pounds thirteen ounces, fhould be
‘reckoned one /9 fix, or one zm feven under proof.

» This definition of proof was adopted in order to accord
with a mode of examination which had been long in-ufe,
and fanétioned by the board.

The hydrometer faid to be invented by Mr. Clarke * was

at
admit an addition of ten gallons of water to reduce it to the ftrength of

“proof; and it aid to be ten per cent. under proof when one hundred
‘gallons contain’ten gallons of water more'than proof contains.

* In 1772 the States of Languedoc offered a premium for the beft me-
moir on the fubjeét of alcertaining the ftrength of brandies. This pre-
mium was adjudged, by the Royal Society of France, to M. Bories, M. D.
whofe invettigation and experiments on this difficult fubject have, 1 hum-
bly conceive, been furpailed only by thofe of the Royal Society in this
gountry. Speakiug of the various methods he had tried, he fays; “ J’eus

, recours

’

154 On the Hydrometer.

at this period brought forward, which having a fet of weights
correfponding to the above-mentioned mixture of water and
proof fpirit, and the mixture of one /o fix, or one am feven,
being that only which weighed an exaét number of pounds
and ounces, without a fractional part, per gallon, by the
ftatute of the 2d of George III. this obfcure mode of afcer-
taining proof was adopted. At this time, the eflects of heat
and cold, on the trial of the firength of {pirits by the hydro-
meter, bad not been clearly underitood ; and though Clarke’s
hydrometer, which was then adopted, by having, in addition
to the weights ufed for afcertaining the ftrengths of ipinits,
another fet of weights called weather weights, adapted to
feveral temperatures, is a demonftration that thefe effects
were not altogether unknown; yet they were confidered fo
immaterial as not to require the mention of temperature in
the act of parliament. This omiffion has added confiderably
to the irregularities of the various hydrometers fince in ule,
as by it the legal fiandard for proof is rendered very uncer-
tain, and will, by the ordinary change of temperature, vary
from five to fix per cent.

I here beg leave to quote an obfervation of fir Charles
Blagden, from the Proceedings of the Royal Society in 1790,
in his Report on the beit Method of proportionating the
Excife upon Spirituous Liquors made by Defire of Govern-
ment: |
« By the act of 2d George ITT, it is ordered, that the

allon of brandy or fpirits, of the ftrength of one to fix under
proof, fhall be taken and reckoned at feven pounds thirteen
ounces (which is underftood by the trade to mean 55 of
heat), Hence taking the weight of a gallon of water at the
fame heat to be 8lb. 5 0z. and 66 parts, the fpecific gravity
of this diluted fpirit will be found 9335 at 60: this {pecific
gravity indicates a mixture of 107 grains of water with 100
grains of pure fpirit; whence, by a computation founded on
the tables in this report, the fpecific gravity of proof fpirit
will come out 916: but the rules of correétion belonging to
Dicas and Quin’s hydrometer give the {pecific gravity of proof
{pirits about 922, at 55, equivalent to g20, at 60. The
former, 916, correfponds to a mixture of 100 parts of fpirit
with 62 by meafure, or 75 by weight of valet and the lat-
ter, 920, toa mixture of 100 parts of {pirit, and 66 by mea-
“recours a la méthode de Fahrenheit ; j'ai vu depuis, qu'elle avoit eté mife
en ufage par M. Briffon. J'entends par cette méthode celle de l’aréomé-
tre ‘eventé par Fahrenheit, et fuivi par Clarke et Defaguliers.” | He after-
wards deferibes the inftrument, and condemns it for its complications,
and being improperly graduated: from this it would appear that this in-
ftrument was invented by Fahrenheit, and not by Clarke.

5 fure,

P
x
‘
5
-

On the Hydrometer. 188

fure, or 80 by weight of water. The difference is confidera-
ble, but the firft is undoubtedly mof conformable to the
exifting acts of parliament: if, therefore, it be thought right
to preferve the term proof /pirit in our excife laws, it may be
underftood to mean fpirit whofe fpecific gravity is 916, and
which is compofed of 100 parts of reétified fpirit at 825, and
62 parts of water, by meafure, or 75 by weight; the whole
at 60 degrees of heat.”

From this extraét it appears there are no lefs than three
imperfections in this manner of defining proof fpirits. Firft,
the fpirit defined is not proof, but another fpirit, one fo fix,
or one zm feven, under proof, requiring a fubfequent procefs
to make proof: fecondly, the difficulty of procuring an exact
gallon meafure.

The late ingenious Mr, Ramfden, in a publication on this

fubjeét, printed in 1792, fpeaking of the ftandard of proof,
fays: “ Hydrometer-makers differ on this point 7£ per cent.3
and government, to avoid difputes, have been under the ne-
ceffity of paffing an act to conftitute Clarke’s hydrometer (for
a fhort time) the only legal one, though it is, in all proba-
bility, as vague as any of the others, particularly in fpirits
confiderably higher than proof. An obtitacle to afcertaining
this term (fays be) arifes from the dithiculty of obtaining pracs
tically the exact capacity of our gallon meafure: it 1s, in~
deed, {tated to contain 231 cubic inches; yet, notwithftand=
ing the great pains taken by a committee of the houfe of
commons, about the year 1758, for that purpofe, affifted by
feveral ingenious mechanics, this point was left undeter-
mined. The method they ufed was making hollow cubes
of different dimenfions, from one inch upwards, which were
executed with great care by the late Mr. J. Bird, and are now
in the repofitory of the houfe of commons: but whoever con-
fiders the difficulty of making an exaét cube, and that of
afcertaining the infide calibre with precifion, muft be fenfible
that no great reliance ean be had on the exaétnefs of a gallon
meafure obtained by this method.”
_ Thirdly, that no temperature being mentioned, the ftrength
is doubtful; and though fir Charles, in this part of his Re-
port (which has not, [ believe, been contradiéted), fays the
trade confiders the temperature to be 55, and that proof {pirit
fhould be as he fiates, by the unerring telt of the fpecific
gravity g16, at 60, (and which would be g18, at 553) yet
the fpecific gravity of proof f{pirit, by Clarke’s hydrometer,
is 924, at 55 of temperature.

From this it appears, that even Quin’s and Dicas’s ftand-
ards of proof are erroneous to an extent of three per cent. i

an

356 On the Hydrometer.

and that Clarke’s is nearly four and a half different from the
firength prefcribed by the ftatute: this is fuppofing the tem-
perature to be what fir Charles fays it is confidered by the
trade.

In Ireland the ftandard of proof is ftill more uncertain, no
definition of it whatever appearing on the ftatute, but refting
folely on the practice which prevailed in England prior to the
2d of his prefent majefty, viz. mixing water with an equal por-
tion of rectified fpirits of wine, asit is called, no f{pecific gra-_
yity of the {pirit mentioned, and the fpirit, called reétified {pint
of wine, differing materially in point of firength : neither has
the temperature been attended to, the hydrometer there hav-
ing no thermometer attached to it: the ftandard of proof has
confequently become juft what the maker of the Infh hy-
drometer pleafed: the generally received opinion, however,
ret had it to be nine per cent. over Englifh hydrometer

roof,

Two material imperfeCtions appear in Clarke’s hydrometer,
exclufive of its complexity; namely, that neither variations
of temperature, nor the gradations of firengths, have been
fufficiently attended to: with refpeét to the former of thefe,
the fame weather-weight (as it is called by the trade) is ufed,
though the temperature fhould vary four or five degrees.

The inventor, forefeeing that this was liable to weighty
objections, conceives he has guarded againft it by the direc-
tion he gives in a N. B.: but this N. B., fo far from remov-
ing doubts, only ferves to increafe them; the words about
and ear leaving room for much to be guefied at, and much
more to be apprehended, where the important points it al-
ludes ‘to are fo Joofely and indiftinétly defined. ,

May I be permitted in this place to explain the confe-
quences of this mode of including four or five degrees of tem-
perature to be indicated by the fame weight, by {tating a cafe
that has frequently occurred ?—-A merchant in Ireland fhips
for London a quantity of fpirit, avid previous to its fhip-
ment examines the ftrength by Clarke’s hydrometer: he
adjufts the firength to be fomewhat lefs than ro per cent.
(fappofe g') over hydrometer proof, the ftrength allowed to
be importable without an augmentation duty: this {pirit is
per fpecific gravity gto, temperature 55. Suppofe it to be ar-
sived in London, but the temperature is then 60; notwith-
fianding this increafe of temperature (of § degrees) the fame
weather-weight continues to be ufed in trying the firength in
England which was applied in Ireland: by this increafe of
temperature, the fpecific gravity being diminifhed to go7 ’ths,
when it comes to be proved in London, by the fame hydro-

: mictery

fel

On the Hydrometer. 157

meter, it then appears to be full one and a half per cent.
ftronger than when it was fhipped, and will now be found ta
be 11 per cent. over proof. Should this fpirit be a foreign
one, viz. brandy or geneva, it muft pay the entire augment-
ation duty of 11 per cent.; whereas, if the temperature was
fufficiently diferiminated, it fhould have paid no augmenta-
tion duty whatever.

That this cafe is not merely a fuppofition, is, I believe,
well known to feveral refpectable merchants in London, to
whom confignments of foreign fpirits have been made from
Treland, and who, in feveral infiances, have been obliged to
pay this augmentation duty of 11 per cent. Here, therefore,
the infirament proves its own errors; nor can additional
weights remedy it.

The principle on which it is conftru&ted fuppofes that the
ratio of expanfion by heat is the fame in flrong as in weak
fpirits; the fame weight for temperature is therefore applied
to both: this is totally erroneous, and is demonftrable thus :
~ Suppofe a weak fpirit to be tried, the fpecific gravity of
which, at the temperature of 35, is g60°48, let the tempe-
rature be increafed to 70, the f{pecific gravity will be 948°13 5
the diminution, confequently, 1s 12°35.

Suppofe next, the fpirit under trial to be a ftrong one, and
is per {pecific gravity at 35, 843:49; increafe the tempera-
ture, as in the firft, to 70, the fpecific gravity will be only
827-01: diminution in this fpirit 16°48; difference in the ratio

f expanfion 4°13; this difference making full three per cent.
by the hydrometer, and thus demonftrating a radical defe&
din the inftrument which cazmot le cured by additional weights.
~The fpirituous liquors of commerce being mixtures of pure
fpirit and water, and the value of this, and the duty to be
paid on it, depending on the quantities of the former which
are contained in the mixture, it becomes neceffary to afcertain
the proportion in which it enters into every fach mixture.

The eafielt and moft expeditious mode of afcertaining this
is by an hydrometer, which aéts on the following well-known
principles of hydroflatics. .

A folid body defcends im a liquid, becaufe it is heavier than
an equal bulk of the liquid: and it defcends with a force or
weight equal to the excefs of its own weight, over the weight
of an equal bulk of the liquid; or, if it be lighter than an
‘equal bulk of the liquid, it afcends with a force proportioned
to the difference of weights; but if it be of the fame weight
as an equal bulk of the liquid, it will remain where it is
placed.

Hence

158 On the Hydrometers

Hence it is evident that every variation of gravity in the
liquid will affect the indication on the hydrometer.

This gravity is known by the term /pecific gravity ; and as
the {pecific gravity of liquids is not abfolute, but relative, this
can only be determined by comparifon: the firft operation,
therefore, confifts in getting one whofe abfolute weight is
known, in order to ferve as a fixed point, and to determine,
in its turn, a comparifon of the denfity of the liquid. Pure
water having always been confidered the beft {tandard for this
purpofe, the term {pecific gravity is moft readily defined, by
faying, that it is as the weight of the liquid is comparatively
with pure water: for inftance, if a phial, which holds pre-
cifely 1000 grains of water, holds only 922 grains of a {pis
rituous liquor, the fpecific gravity of this fpirit is faid to be

Be
nie as fpirits expand by heat, and contraét by cold, this
fpecific gravity varies according to the degree of the heat of
the liquor, which is called its temperature: therefore it is
necefiary firft to afcertain what that may be, and it is done
very accurately by the thermometer. And in the experi-
ment mentioned, fuppofing the temperature to have been 55,
if the fpirit be heated to 70, the fpecific gravity will be di-
minifhed to 91545 and, if afterwards it be cooled down to
35 degrees of temperature, it will be found to have increafed
to 930.

This is a very convenient manner of trying and expreffing
what the fpecific gravity of the liquor may be; and as I fhall
hereafter have occafion to ufe the term frequently, I hope I
fhall be excufed for explaining it in this place.

All the variations of the fpecific gravity of {pirituous liquors,
and the cauies of them, may be comprifed under the follow-
ing heads, viz.

ft, Thofe arifing from heat and cold: adly, A difference
in the proportions. of the fpirit and water: and, 3dly, The
effects of penetration (or, as it 1s called, concentration
which takes place on the mixture; all of which, being
clearly define by fir Charles Blagden, in his Report on this
fubject, in the fecond part of the 8oth volume of the Tranf-
actions of the Royal Society, I fhall beg leave to give it in
his words, and lament that the propofed limits of this work
will not permit me to give the entire Report, every paragraph
of which [ conceive to be important, and demonftrates the
difficulties with which this fubjeé&t is enveloped, and very
clearly points out the way to remove them.

** Though (fays fir Charles) various jndications of the

ftrengths

On the Hydrometer. 159

firengths of fpirituous liquors have been devifed, applicable
in a grofs manner to a general ufe, it is well known that no
method admits of real accuracy but that of the fpecific gra-
vity. The weights of an equal bulk of water and pure fpirit
differ from one another by at leaft a fixth part of the weight
of the former; whence it is ebvious, that when thofe two
fluids are mixed together, the compound mut have fome
intermediate {pecific gravity, approaching nearer to that of
water or pure fpirit, as the former or the latter is the more
predominant ingredient.

‘© Were it not for a certain effect attending the mixture
of water and {pirit, which has been called their mutual pe-
netration, the fpecific gravity of thefe compofitions, in a
given degree of heat, would be fimply in the arithmetical
proportions of the quantity of each of the fluids entering into
them. i

<* But whenever different fubftances, which have a ftrong
tendenvy to unite together, are mixed, the refulting compound
is found to occupy lels fpace than the fubftances forming it
held in their feparate ftate; wherefore the fpecific gravity of
fuch compounds is always greater than would be given by a
fimple calculation from the volume of their ingredients.
Though it be a general fact, that fuch a decreafe of bulk
takes places on the mixture of fubftances which have a che+
inical attraction for each other; yet the quantity of this di-
minution is different in them.all, and, under our prefent ig-
norance of the intimate compofition of bodies, can be deter-
mined by experiment only. To afcertain, therefore, the
quantity and law of the condenfation refulting from this
mutual penetration of water and fpirit, was the firft object
to which the following experiments were directed.

** All bodies, in general, expand by heat: but the quan-
tity of this expanfion, as well as the law of its progreffion,
are probably not the fame in any two fubftances. In water
and fpirit they are remarkably different. “The whole expan-
fion of pure [pirit, from 30° to too” of Fahrenheit’s thermo-
meter, is not lefs than 1-25th of its whole bulk at 39°;
whereas that of water, in the fame interval, as only 1-145th
of its bulk. The laws of their expanfion are {till more dif-
ferent than the quantities. If the expanfion of quickfilver
be, as ufual, taken from the ftandard (our thermometers
being conftrnéted with that fluid), the expantion of fpirit
is, indeed, progreflively increafing with refpect to that ftand-
ard, but not much fo within the avove-mentioned interval ;
whilft water kept from freezing to 30°, which may eafily be
done, will abfolutely contract as it is heated, for ten or more

La degrees,

160 On the Hydrometer. .

degrees, that is; to 40° or 42° of the thermometer, and will
then begin to expand as its heat is augmented, at firft flowly,
and afterwards gradually more rapidly, fo as to obferve upon
the whole a very increafing progreflion.

“¢ Now mixtures of thefe two fubftances will, as may be
fuppofed, approach to the lefs or the greater of thofe progref-
fions, according as they are compounded of more fpirit or
more water; whilft their total expanfion will be greater ac-
cording as more {pirit enters into their compofition: but the
exaét quantity of the expanfion, as well as the law of the pro-
greffion, in all of them, can be determined only by trials.
Thefe were therefore the two other principal objects to be
afcertained by experiment.” Sir Charles then proceeds to
defcribe thofe various experiments, and which are too long
to admit an infertion of them here; but from a perufal it will
be perceived they were conducted with a degree of patient
inquiry, minutenefs of attention, and accuracy of inveftiga-
tion, feldom to be met with, and which, with the calcula-
tions grounded on them by Mr. Gilpin, clerk of the fociety,
and publifhed in the Tranfactions for 1794, have removed
thofe obfcurities with which the fubjeét had heretofore been
enveloped.

Thefe celebrated experiments, and the table deduced from
them, have been minutely examined by feveral of the ablett
philofophers in Franee and various other parts of the conti-
nent, and they are allowed to be what Mr. Nicholfon (who
has alfo minutely examined them), in his Chemical Dic-
tionary, fays, may be confidered as fundamental refults; and
it is fomewhat remarkable that, fince their publication in
1794, no perfon has hitherto availed himfelf of the important
information they contain, a§ a foundation for putting a pe-
riod to thofe irregularities and uncertainties which have been
fo long and fo univerfally complained of. ;

That hydrometers fhould be complicated in their ftruc-
tures, and erroneous in their indications, previous to this
period, is not to be wondered at.

The fpecifie gravity of the fpirit, which is the foundation
of the hydrometer indication, was but little attended to; and
thofe variations which take place in the fpecific gravity,
through the feveral caufes above mentioned, having never be-
fore that period been precifely afcertained, hydrometers, in-
ftead of being graduated by this unerring teft, have been gra-
duated by comparifon ‘with anotber infirument, called a
‘ ftandard, but no means.have been pointed out to prove that
this ftandard was correct.

Thefe tables of Mr, Gilpin, however, furnith fuch elemen-

7 nae

On the Hydrometer. 16k

tary information as has .enabled me, by the addition of four
columns, to remove all doubts and uncertainties on the fub-
jet, by demonftrating, from the fpecific gravity of the {pi-
rituous liquor, what the hydrometer indications fhould be
of every gradation of ftrength.

In the Report, which accompanies thefe tables, fir Charles
Blagden makes an obferyation which firft fuggefted to me the
utility of thefe additional columns.

‘* It may very probably be thought right (fays he), for the
future ufe of the revenue, to compute another fet of tables,
in which the degrees of heat ftanding at the head of each
table, the firft column of it fhall be even numbers of {pecific
gravity. This would be proper for looking out at once the
quantities of fpirit and water in a mixture from its heat and
{pecific gravity.”

Sir Charles, by this obfervation, alludes not to the means
of obtaining the hydrometer indication, but to an opinion he
had given in his firft Report, in 1790, that the fimpleft and the
moft equitable way of levying the duty on fpirituous liquors
would be to confider pure fpirit as the true and only excife-
able matter, inftead of the relation to the ftandard of proof,
and for calculating which one column of the table is a deci-
mal multiplier, to afcertain the proportion of this in any given
quantity of a fpirituous liquor; an idea which certainly 1s in-
genious, and, at firft view, appears to have the reeommenda-
tion of fimplicity: but as every difcrimination of ftrength
would require an operation of figures, fractions would un-
avoidably occur, from which, and the delay and danger of
errors in thefe operations, this mode, I conceived, had been
confidered practically inconvenient, and therefore was not
adopted. z

The relation to the ftandard of proof having been long re-
tognized by the different ftatutes, and in commerce, I thought
it probable it would not be laid afide; nor was it, as I con-
ceived, neceffary to do fo when a means prefented itfelf of
rendering this relation to proof equally correct as that which
he pointed out: and the new fet of tables, which at firft I
apprehended he was about to defcribe as ufeful for the reve-
nue, were thofe which would deduce the hydrometer indica-
tion of flrength from the fpecific gravity of the fpirit at a
given temperature. A table for this purpofe would, I con-
ceived, be importantly ufeful on feveral accounts: 1ft, it
would afford a mode of graduating an hydrometer on a cer-
tain principle; and, 2dly, that as it furnithed a ftandard for
every gra tation of ftrength, errors could be difeovered in thofe
infiruments that have been graduated by the delufive mode of

Vou. XIV. No, 54. L comparifon

162 A foort Account of the Mammoth.

comparifon, many of whofe difcriminations of ftrength being,
as I had reafon to believe, merely conjectural.

Before I proceed to explain Mr. Gilpin’s tables, and the
columns added to them, it becomes neceflary to define what
is meant by the term pure /pirit, and to inquire whether the
fpirit which fir Charles defcribes can with propriety be called
fuch.

‘© The firft ftep (fays he, in the Report made on this fub-
ject in 1790) towards a right performance of the experiments,
was to procure the two fubflances with which they were to
be made, as pure as poffible. Diftilled water is in all cafes
fo nearly alike, that no difficulty occurred with regard to it ;
but the fpecific gravity of pure fpirit, or alcohol, has been
given fo very diflerently by the authors who have treated of
it, that a particular fet of experiments appeared neceflary for
determining to what degree of ftrength rectified fpirit could
conveniently be brought. The perfon engaged to make thefe
experiments was Dr. Dollfufs, an ingenious Swifs gentleman,
then in London, who had diftinguifhed himfelf by feveral
publications on chemical fubjects. Dr. Dollfufs, having been
furnifhed by government with {pirit for the purpofe, rectified
it, by repeated and flow diftillations, till its fpecific gravity
became ftationary an this manner of operating: he then
added dry cauftic alkali to it, let it ftand for a few days,
eae off the liquor, and diftilled it with a fmall addition of

urnt alum, placing the receiver in ice. By this method he
obtained a fpirit whofe fpecific gravity was 8188, at 60 of
heat. Perceiving, however, that he could not conveniently
get the quantity of fpirit he wanted lighter than 82527, at
60, he fixed upon that ftrength as a ftandard. ;

Several highly refpectable authorities might be produced
to prove this {pecilic gravity to be a proper ftandard for pure
[pirit.

It [ Tobe continued. ]

——

XXVL. A foort Account of the Mammoth. By Mr. Rem-
BRANDT PEALE*. .

Tue mammoth is fo called from the Ruffian name, fup-.
pofed to have been derived from the Hebrew Behemoth,
Job, chap. xl. It is properly continued, both words being
expreffive of a large and extraordinary animal.

For a number of years paft many large and extraordinary

' * Communicated by the Author.
bones

.

A fbort Account of the Mammoth. 163

bones and teeth have been difcovered both in Siberia and
America, which at firft were generally attributed to the ele-
phant *, except fome very large teeth of the carnivorous kind
totally different from thofe of any animal known.

In Siberia they were attributed to the mammoth, whofe
fabulous ‘exiftence they fuppofed to be under ground, and of
which I{brand Ides pretends to give a defcription. In North
America thefe large bones and carnivorous grinders have
been found in great abundance on the Ohio and its tributary
ftreams, wathed from their banks, or difcovered by digging
in falt moraffes in the neighbourhood of Cincinatti; where
they are found intermixed with the bones of buffaloes and
deer, which a tradition of the Indians ftates to have been de-
firoved by a herd of thefe animals which came upon them
from the north. This event happened, the Indians believe, asa

-punifhment for their fins; but they fay the good fpirit atlength

interpofed to fave them, and, feating himfelf on a neighbour-
ing rock, where they fhow you the print of his feat and of
one foot, hurled his thunderbolts among them. All were
killed except one male, who, prefenting his forehead to the
fliafts, fhook them off, until, at length wounded, he fprung
over the Wabath, the Illenois, and the Great Lake, where he
fill lives.

Thefe bones were forwarded with great eagernefs to all
parts of Europe, and depofited in mufeums, where they at-

traéted ‘the curiofity of all naturalifts, whofe conjeCtures and
theories on them were very various, until Dr. Hunter, by a

more accurate comparifon between them andthe bones of
other animals, determined that they mutt have belonged to a
dase non-defcript animal of the carnivorous kind, fomewhat
mbling the hippopotamus and the elephant, yet effentially
different from both,
The fubjeét is now completely elucidated. Not long fince
me farmers in the State of New York, in America, digging
marle from their moraffes in the neighbourhod of New-
Windfor, accidentally difeovered feveral of thefe bones, which
were preferved by phyficians in the neighbourhood, In the au/
tumn of 1801, ny father Charles W. Peale and myfelf, having
obtained poffeflion of thefe bones, perfevered for nearly three
months, at the expenfe of much time, labour, and money, in
a fearch for the remainder of the animal; and were fortu-

* Naturalifts were led to this idea in confequence of finding, in a few
inftances in America, but frequently in Siberia, fome large graminivorous

“teeth, which probably belonged to an animal of the elephant kind, thougt

certainly of different {pecies from any known : thefe reeth are remarkable for
fize, and in the number of lamellated veins of enamel which pervade them.

La nate

——_—™_ -”

fponding parts of all animals there is a general analogy, it is

164. A foort Account of the Maminoth.

nate enough to obtain two fkeletons, found in two diftin&
fituations, and unmixed with bones of any other individual
whatever : one of thefe is preferved in the Mufeum at Phila-
delphia, and the other is now exhibiting in the Old Academy-
room, Pall-Mall, previoufly to its being taken to Paris.

The fkeleton of the mammoth bears fome general, refem-
blance to that of the elephant, yet on examination even the
general figure is found to be confiderably different; princi-
pally in the effect of the tufks, firucture of the head, promi-
nence and pointednefs of the back over the fhoulders, ils
great defcent thence to the hips, together with the compara-
tive {mallnefs of the body and the neceifarily detached effect.
of the hind-legs—proofs of greater, activity than in the ele-
phant. Ona clofer examination, the characteriftic features
are greatly multiplied; and with refpect to the hind-legs, the
idea of activity is confirmed from the ftructure of the thigh-
bones, which are extremely broad and flat, and well adapted
for great exertions of ftrength, beyond that of the elephant,
whofe thigh-bones are not flat, but round. This effeét of
ftrength likewife prevails in the ribs, which are of a very un-
ufual ftructure, being bent edgewife and having their greateft
thicknefs at top, gradually becoming fmaller towards their
junction with the cartilage; whereas in the clephant they are

bent flatwife, like thofe of the ox, and are narrow at top and

broad at the lower ends. This peculiarity in the ribs of the

“mammoth is worthy of particular notice, not only on account

of the unufual pofition of firength, but becaufe, from their

~ diftance between each other, they fhow the animal. to, have

had confiderable flexibility in its body; to which the breadth

: and proximity in the ribs of the elephant, as well as. the ox,
are a certain impediment. _Befides, as I obferved before, the

body is comparatively fmaller, in confequence of the fmall
Jength of the ribs.

The fpines of the back over the fhoulders are of an unufal
magnitude, which gives the appearance of a hump, like the
bifon, and are calculated to give power and motion to the
head, Thofe in the elephant are not fo large over the fhoulders,

~ but much more fo all the way to the facrum : confequently
- his back is more arched. The proportionate length of the
_ procefles from the fpine of the fcapula differs effentially from

all other animals. And, independently of any other variation

in form, all the bones, of the limbs in particular, are afto-
. nifhingly thick and ftrong.

We now come to the bead, where the moft ftriking features
of this animal are to be found ; and fince between the corre- '

the

A Short Account of the Mammoth. 165

the province of comparative anatomy not only to trace out
the points of diftinétion, but, fince they originate from cer-
tain fixed principles, in the difcrimination of variations,
to confirm their propriety by an examination of the princi-
ples on which they are founded. |

Although it is fufficiently evident to thofe who are accuf-
tomed to this kind of inveftigation, from the obfervation of
a few facts, that this animal muft have been carnivorous ; yet)
to others it is neceflary to introduce every proof and conclu-
five evidence. Many perfons, from a falfe impreffion, be-
lieve that teeth are determined to be carnivorous merely from
their having a rugged furface: with this opinion they very
properly afk, ‘¢ May not the vegetable food be of a coarfer
quality?” It is true that the furface is rougheft on thofe
graminivorous teeth which are employed in the maftication
of the coarfeft vegetable fubftances, not only becaufe fuch
roughnefs is requifite, but becaufe the teeth are rendered
fo from the quality of the food, the bony interftices wearing
down more eafily than the ridges of enamel, which operate
as the roughnefs ina mill-ftone. It is not therefore from
this fpecies of roughnefs that we prefume on {fo important a
determination: the roughnefs exifting on the furface of car-
nivorous teeth is of another nature, much more ftrongly
marked, and far from being rendered fo by ufage : the more
they are ufed, the mage even do they become. The tooth of
a graminivorous animal is compofed of alternate veins of
enamel and bone, which thus pervade the whole mafs : thofe
of carnivorous animals are covered with a fhell or cruft of
enamel, which is merely external, and exifts as well in the
cavities as on the ridges; which is not the cafe with other
teeth. This enamel is required in the cayities, becaule the
téeth interlock with each other, the prominences ftriking
into the cavities.
*An uniform compofition of tooth, as it refpects the inter-
mixture of enamel and bone, is obferved to prevail in thofe
of the elephant, horfe, ox, &c. principally differing from
each other in the figure which thole veins of enamel affume,
and by which alone they may be difcriminated among them-
felves. On the other hand, carnivorous teeth, incrufted with
enamel as far as the gunis, yet vary in the form and number
of their protuberances, fo as generally to defignate their
{pecies : yet among them there is a very proper diflinétion to
be obferved, which is, that thofe carnivorous animals, the
form of whofe teeth and the attachment of whofe jaws allow
them the fide or grinding motion, are always of the mixt
kind. Man, the monkey, hog, &c, are carnivorous aai-

L 3 mals,

165 | <A fbort Account of the Mammoth. .

mals, becaufe their teeth are incrufted with enamel, and be-
caufe they do eat flefh ; yet they are adapted for other food,
by the rotatory motion of their jaws and the form of their
teeth: this rotatory motion does not exift in the jaws of thofe
animals which live entirely upon flefh; for they are attached by
an oblong head or procefs inferted into a tranfverfe groove, and
confequently have no other motion than up and down. In
graminivorous animals the under jaw is attached by means
of a confiderably round head (condyloid procefs) to a pro-
minence or flat furface, fo that they rotate; and, to favour
this motion, the coronoid procefs is generally thicker and not
fo long as the condyloid; whereas in carnivorous animals
the coronoid procefs is extremely flat and long, being never
acted on except lengthwife.

But it muft not even be fuppofed that an animal may be
of the mixt kind, unlefs we obferve a capacity for maftica-
tion; without which we muft declare it exclufively carni-
vorous.

“Some obje& to the carnivorous nature of the mammoth
from its not having cutting or canine teeth. To this it ma
be replied, that if we form our rule of judgment, as to wha
conflitutes a graminivorous animal, from the confiruétion o
an ox’s jaw, the elephant would certainly be excluded, be-
caufe it has not znci/ores at leaft in the lower jaw: the fact is,
that all carnivorous as well as graminivorous animals differ
among themfelves with refpeét to the number and fituation
of their teeth; and hence they afforded to the fagacious and
celebrated Linnezus the moft infallible method of claffifica~
tion, which has fince been adopted, either wholly or partially,
by all naturalifls. The probofcis of the elephant anfwers
the purpofe of incifores': he therefore requires’no others than
grinders, which entirely fill his jaws: hence he is com-
pletely graminivorous. And although the mammoth is de-
ficient in cutting teeth, and has no otber canine teeth than
his enormous tufks, the deficiencies of which may have
been fupplied by a pair of large and powerful lips, indicated
by the uncommon -finuofity on the front of the lower jaw;
yet I am decidedly of opinion, fince it cannot be contra-
diéted by a fingle proof or fact, that the mammoth was ex-
clufively carnivorous; by which I mean, that he made no
ufe of vegetable food, but either lived entirely on flefh or fith ;
and not improbably upon fthell-fith, if, as there are many
reafons to fuppofe, he was of an amphibious nature. I there-
fore only require affent to thefe facts: 1ft, The teeth are cer-
tainly of the carnivorous kind: adly, They are not of the
mixt kind, becauig they have not the leaft rotatory sa

an

A fhort Account of the Mammoth. 167

and fo completely lock together: 3dly, Since, therefore,
they are not graminivorous, fince they cannot be of the mixt
kind, from a defect in motion, they muft be exclufively and
pofitively carnivorous.

Independently of the teeth, the under jaw of the mam-
moth differs moft effentially from that of the elephant, which
in its outline is femi-circular, from the condyle to the chin;
whereas in the mammoth the outline is diftin@ly angular,
land is much greater in the length than it is in the height,
which is the reverfe in the elephant: befides feveral other
ftriking diftin&tions in both jaws.

When the fkeleton was firft erected, I was much at a lofs
how to difpofe of the tufks; their fockets fhowed that they
grew out forwards, but did not indicate whether they were
curved up or down. I chofe, therefore, firft to turn them
upwards, not becaufe they produced the fame effect as in
the elephant, for it is evident tley could not in any pofition,
owing to two circumftances. In the elephant, taking the level
of the teeth for a horizontal bafe line, the condyle of the neck
is at right angles with it; and the perpendicular, one third
longer than the bafe line: hence they are ufeful on every
occafion, the tufks themfelves being nearly ftraight, and

ointing downwards ; whereas in the mammoth, taking the
hae of the teeth for a bafe line, the condyle of the neck is
fituated but a few inches above it: confequently the fockets
for the tufks and the condyle of the neck are in a horizontal
direétion : this circumftance, together with the extraordinary
curve of the tufks, would raife the points in the air, directed
in fome degree backward over the head, twelve feet from the
ground, and never could have been brought lower than fix or
feven feet from it. This pofition was evidently abfurd: I
therefore refolved on reverfing them; in which pofition, in
confequence of their twift or double curve, they appear infi-
nitely more ferviceable.

Six miles from the {pot where this fkeleton was difcovered
we found two entire tufks, in form exactly like thofe in the
fkeleton, but very much worn at the extremities (the point of
one I have with me), and worn in fo peculiar a manner, con-
fidering their form, as could not haye bappened in an ele-
vated pofition; unlefs on the abfurd fuppofition, that the
animal amufed himfelf with wearing and rendering them
blunt, by rubbing them againft high and perpendicular
rocks: this in a flate of nature can never be fuppofed,
whatever habits may be acquired when in a narrow confine-
ment. There can be no doubt, then, of their having been
wfed againft the ground, and not improbably in tearmg up

L 4 ) fhell«

>

h

168 A fhort Account of the Mammoth.

fhell-fith, if, as we have many reafons to fuppofe, he was of
an amphibious nature : for this fpecies of food his teeth feem
admirably adapted. All animals of fimilar habits have fimi-
lar teeth : this animal. has teeth unlike any other with which
we are acquainted: there is much reafon, therefore, in fap-
pofing his food to have been different; efpecially when we
confider the thicknefs of enamel which covers the teeth, the
peculiar manner in which they are worn, and the fmall
opening for the throat. But, whether amphibious or not, in
the inverted pofition of tbe tufks he could have torn an ani-
mal to pieces held beneath his foot, and could have ftruck
down an animal of common fize, without having his fight
ob{tructed, as it certainly would have been in the other pofi-
tion. ;

The tufks themfelves are compofed of two very diftinc&
fubftances: the internal bony or iyory part, which we find
‘in the greatett ftate of decay; anda thick, diftinét coating,
doubtlefs having undergone fome decay, yet at prefent abfo-
Jutely heavier and harder than the frefheft ivory. No part of
the {keleton is petrified, but all in their prefent ftate of pre-~
fervation from having been furrounded by a calcareous foil,
compofed principally of decayed fhells, and covered with
water even in the drieft feafons.

How long fince thefe animals have exifted, we fhall per-
haps ever remain in ignorance; as no judgment can be
formed from the quantity of vegetable foil which has accu-
mulated over their bones. Certain we are, that they exifted
in great abundance, from the number of their remains
which are found in America: we are likewife fure that they
mutt have been deftroyed by fome fudden and powerful
caufe ; and nothing appears more probable than one of thofe
deluges or fudden irruptions of the fea, which have left their
traces in every part of the globe, and which are in amazing
abundance on the very fpot where thefe bones are found:
they confit of petrifactions of fea produdtions, fhells, corals, |
&c. It is extremely probable that, whenever and by what-
ever means the extirpation of this tremendous race of animals
was effected, the fame caufe muft have operated in the de-
firuction of all thofe inhabitants from whom we might have
received fome fatisfactory account of them. Ade:

Dimenfions of the Skeleton,

Fe. In
Heicht over the fhoulders - M ° Chit.
Ditto over the hips e 9 9
Length from the chin to the rump a ~ ch eee

PE OL BO SN

New Theory of the Con/litution of mixed Gafes elucidated. 169
From” the point of the tufks tothe endof the = Fr. In.

tail, following the curve - - 31 0
Leneth in a firaight line - - - ye ke
Width of the hips and body - - 5 8
Length of the under jaw - - - 2 10
Weicht of the fame - 632 pounds
Width of the head - = - 3.2
Length of the thigh-bone - - - hag
Smalle(t circumference of the fame - ~ I 6
Length of the tibia - - - 2 0
Length of the humerus, or large bone of the

fore-leg - - - - 2 10
Largeft circumference of the faine - - 3 vias
Smalleft ditto ditto - . - Bilge:
Length of the radius - - - 2 55
Circumference round the elbow - - Siva
Length of the {capula, or fhoulder-blad - a, ee
Length of the longeft vertebra, or back-bone 2 3)
Longeft rib, without cartilage - - arg
Length of the firft rib - - - 2 0
Ditto of the breaft-bone - - - 4 0
Length of the tufks, defences, or horns - nis fat,
Circumference of one tooth or grinder - r 65

Weight of the fame, 4 pounds Io ounces
The whole fkeleton weighs about 1000 pounds.

XKVIT. New Theory of the Conjftitution of mixed Gafes elu-

cidated. By J. Dauton, Efg.* |

Ix an effay, publifhed in the Memoirs of the Literary and
Philofophical Society of Manchefter, vol. vy. part 2, I gave a
new theory of the conftitution of mixed gafes, and particu-

larly of the atmofphere, and endeavoured to illuftrate m
meaning by a plate, &c. Notwithftanding this, I am in-
formed by fome of my chemical friends that they do not
clearly underftand the hypothefis itfelf, and confequently ar
not able tq judge of its merits or defects: anda late gg
(Dr. Thomfon) in his Syftem of Chemiftry, vol. iil. p. 270
{peaking of the uniform diffufion of the different gafes of th
atmolphere, makes the following obfervation :—‘* Even Mr
Dalton’s ingenious fuppofition, that they neither attrac no
repel each other, would not account for this equal diftribu
tion ; for, undoubtedly on that fuppofition they would arrang

* Communicated by the Author,
themfelve

170 _ New Theory of the Confiitution °

themfelves according to their: fpecific gravity.” Now, as I
am perfuaded that no one acquainted with the principles of
mechanical philofophy could have written the above if, he
had underftood my hypothefis, it feems to call from me a
further explanation. I propofe therefore, 1ft, To:ftate, in as
clear a point of view as the fubject will admit, the principles
which I affume: 2d, To fhow that the confequences which I
have deduced from them are legitimate ; and, particularly, that
mixed elaftic fluids ought mo# to arrange themfelves according
to their {pecific gravity: and, 3d, To demonttrate that the
fuppofition of the gafes conftituting the atmofphere being
held in a ftate of equal diffufion by chemical afiinity, is not
only inconfiftent with the phenomena, but is completely
abfurd.

I. Principles affumed.

1. I take for granted, that the particles of fimple [un-
mixed] elaftic fluids repel one another with forcesinyerfely
as the diftance of their centres, the temperature being given.
This is a mathematical deduction from the allowed fact, that
the fpace occupied by any gas is inverfely as the comprefiing
force. (See Newton’s Principia, b. il. prop. 23.) The ad-
folute diftances of the centres of fuch particles muft vary ac-
cording to circumftances, and cannot eafily be determined ;
their re/ative diftances in a Jiquid and aérial ftate fometimes
may. Mr. Watt has fhown that fteam of 212°, and preflure
28 inches,’ is 1800 times lighter than water; confequently
the diftancés of the particles of fteam are to the diftances of.
the faid particles in a liquid ftate as 12 to 1, nearly, in that
particular cafe. Vapour in the vacuum of an air-pump, at
common temperature, will have its particles about four times
the diftance, or 48 tor. |
2. I fuppofe that in mixed elaflic fluids the heterogeneous
articles do not repel one another at all at fuch diflances as
they repel thofe of their own kind; but that fuch particles,
when brought into adtual contaét (to ufe the common lan-
guage), refift each other in all refpeéts like inelaftic bodies.
This is the peculiarity of the hypothefis, and what appears
not to be generally underflood. If I may explain by analogy,
the moft ftriking will be found in magnetifm. Two hke
poles of magnets repel one another with the fame force, whe-
ther any other bodies intervene or not, and do not affect thofe
other bodies: in the fame way I conceive two particles of any
one gas repel one another with the fame force, whetber par-
ticles of other gafes intervene or not, and do not affect thofe
other particles. A magnet is amenable to ihe common Jaws

7 of

of mixed Gafes elucidated. 17%

of motion in its collifion with other bodies, and when it is
brought into feeming contac with them ; fo is a particle of
one gas when it is brought inte feeming contaét with a parti-
cle of another fpecies; and in this cafe the bodies may be
faid to have a repulfive power: but this power is effentially
different from the other, in that it extends to no definite di-
fiance. Further, conceive a very fine capillary tube placed
perpendicular to the horizon, into which let a number of
correfpondent fmall magnetic wires, or particles, be inferted,
with their poles of the fame denomination together, or, more
firiétly, as near as their repulfive power would admit, one par-
ticle above another, the air having intercourfe amongft them.
Then, as the magnetic particles would not actually touch one
another by reafon of their repulfion, they would /eem to be
fupported by the intervening air; whereas in reality they are
fupported and kept at certain diftances entirely by the repul-
fion inherent in themfelves and their own gravitation: and
thus, I conceive, particles of gas fupport thofe of their own
kind above them, though, were they vifible, they might feem
to reft upon others immediately under them ; and the ground,
or lowell folid or liquid furface, by fupporting the loweft par-
ticle of each kind, has the weight of the whole to fuftain.
Thefe obfervations, together with a view of the plate above
alluded to, muft, I think, be fufficient to fatisfy® any one
what the hypothefis is. And it may be proper to add, there
is fomething much refembling polarity obfervable in the ul-
timate particles of bodies at the inftant of tranfition from the
liquid to the folid ftate: witnefs the congelation of water.

II. Confequences.

It is plain from the above account that I conceive any one
gas to be conttituted of perhaps ove part folid matter, and one
thoufand or more parts vacuity or pore, if it may be fo called ;
and that into this vacuity we may throw as many other gafes
as we pleafe without materially difturbing the firft, provided
we do not abfolutely fill the vacuity with folid matter (for fo
I denominate common liquids or folids). Thus, we might
have had a dozen gafes in our atmofphere inftead of three or
four, all in the fame compafs, and each retaining the fame
denfity it would have had alone. The heavier gas has no
more tendency to raife the lighter than a quantity of fhot has
to expel the air from its interftices. If therefore Dr. Thom-
fon, or any other, can fhow how one fluid, which is not dif-
placed nor any way acted on by another, fhould by its re-
aétion caule that other to move into a higher or lower flation,
then the mathematical world will be obliged to. reconfider

their

72 New Theory of the Conftitution of mixed Gafes elucidated.

their doétrine of flatics. ‘Till then I muft take the negative of
the propofition, and conclude that elaflic fluids of the greateft
and leaft fpecific gravity imaginable, on the fuppofition I hold,
will alike take the loweft and the highett ftations, regardlefs
of each other; or, in other words, they will arrange themfelves
in the fame order as if thrown into a complete vacuum. The
ta difficulty refpecting the uniform ditfufion of the gafes ”

ine removed, I think on my hypothefis the other phano-
mena can require no explanation to any perfon converfant in
pneumatics. I will take one inftance: it may be afked, How
does fulpburet of potafh abftract oxygenous gas ont of any
mixture; lime water, carbonic acid gas, &e. &c.? The an-
fwer is obvious: Exaétly in the fame way as if the gas in
gueftion was the only one in the’ veffel, and the operation
going on in a clofe vetlel,

If. Gafes held together by chemical A ffinity abfurd.

On this head it will be proper to premife certain facts:

ift, When two gales of different fpecific gravity, fuch as
exygenous and hydrogenous, are put into the fame veffel and
agitated; then, after ftanding fome time, they full continue
uniformly mixed. ;

2. They occupy the fame fpace before and after mixture ;
that is, ove meafure of each put together occupy two mea-
fures, the temperature and preffure being the fame. Mr,
Davy feems to think this principle not ftriétly true in regard
to a mixture of azotic and oxygenous*gas; but the deviation »
from it, if any, 1s extremely {mall.

3. The compound is fubjeét to the fame laws of rarefaétion
and condenfation as the fimples. “ht

There are but ¢bree fuppofitions we can make effentially
different refpecting the mutual action of heterogeneous par-
ticles of gas. ft, When two gales are mixed, their particles
may reciprocally repel one another, juft as they a€t on their
own kind in an unmixed flate: 2d, They may be neutral, or
have neither atiraGtion nor repulfion for each other: 3d, They
may have a chemical affinity or adéraédion for each other.
The advocates for the chemical adhefion of gafes will agree
with me in exploding the fr/l, becaufe, where nothing but
repulfion is manifeft, we can afcribe no effect to attraction:
the fecond, which is the one I adopt, is obvioufly inconfiftent
with their hypothefis: and as for the ¢bird, 1 can conceive
no other explanation than the following: 1{t, Two or more
heterogeneous particles may unite, and become a new centre
for the caloric to adheye to; but in this cafe the gales are no

ot aia 5 ~ ~ longer

Royal Society of Londor. 55g

longer éwo but one, and oxysenous eas and hydrogenous will
become aqueous vapour : this, therefore, would not bea cafe
of two gees held together by affinity. — 2:) Pwo wales may
feparately retain their caloric, andftill be*held ‘by chemical
affinity; that is, there may be an -equilibriim tbetween the
powers of attrattion and repulfiom: but this: isievidently \in-
confiftent with the third Jaw of condenfation;and rarefaction,

obferved in fuch compounds. + | s bodes .
Manchefter, s JoDALron.
Noy. 20. " ; Hl Sak ey ied .

Note. 1 haye lately read a paper.to the Literary and Philo-
fophical Society of Manchefter,, in which I have fhown that
the quantity of carbonic acid gas found in a given volume of
atmo/pheric air is not mere than 5.,th, part,of the whole;
and that the faid gas is held in water, not by chemical affi-
nity, but merely by the preffure of the gas, abftractedly con-
fidered, on the furface, forcing it into the pores of the water.

XXVIII. Proceedings of Learned Societies.

ROYAL SOCIETY OF LONDON,

Ta IS learned body bas recommenced its labours by be-
{towing on count Rumford the firft medal awarded from the
fund provided by the count, himlelf for difcoveries on the
nature and properties of heat.

The Copley medal has been adjudged to Dr. Woolafton.

On the firlt night of meeting, which was on the 11th of
November, the Bakerian le&ture was delivered by Dr. Wool-
alton. The fubjeét, horizontal refraction. .

On the 18th was read a paper, by, Mr, Chenevix, on the
ehemical properties of the humours of the eye; and one by
Mr. Smithfon on calamines or ores of zinc.

On the 25th, a paper, by M. Aldini, on the galvo-electri-
city of hot-blooded-as well as cold-blooded animals. The
experiments detailed in this curious paper are fimilar to thole
of which we gave an account in our laft, and to fome detailed
in a fubfequent page of our prefent number.

_ FRENCH NATIONAL INSTITUTE.

* Account of the labours of the Clafs of the Mathematical
and Phyfical Sciences during the laft quarter of the year 10.
——The mathematical part by Lacroix fecretary.

ASTRO-

T4 French National Inflitute.
ASTRONOMY,
Calculation of Obfervations of two Occultations of the Spica
Virginis by the Moon, which took place in the Year o>

Difcovery of a new Comet—Ob/ervations of the Planet dif/-

covered by Dr. Olbers.

Occultations of the ftars by the moon are fo ufeful for im-
proving geography, by determining the longitude, that they
~ have been ranked among the moft important of the celeftial
phenomena; and in this clafs thofe eafieft to be obferved,
and which give the fureft refults, are occultations of ftars of
- the firft magnitude.

The moon, by the pofition of its orbit, can eclipfe only
four; namely, Aldebaran, Regulus, Centares, and the Vir-
gin’s Spike; but the paffage of the latter behind the moon’s
difk rarely takes place. C. Lalande knows only four epochs
in the fpace between 1623 and 1790; and the year g havin
exhibited two, he took care to unite and calculate the obfer-
vations which reached him of this phenomenon.

For the firft occultation, which took place on the 3oth of
March, thefe obfervations are in number fixteen, of which
the city of Paris alone furnifhed fix, carefully made by the
moft diftineuithed aftronomers. It was from an obfervation
made by C, Ciccolini, at Florence, that Lalande determined
the longitude of that city, which he publifhed fome time
ago, exprefling his aftonifhment that the pofition of a city of
fo much importance fhould have hitherto been fo inaccu-
rately fixed.

The longitude of the moon, deduced from obfervations at
the time of the conjunction of thefe two bodies, is lefs by 13"
than that given in the tables lately tranfmitted to the board
of longitude by M. Burg.

Fourteen. obfervations of the fecond occultation, which
took place on the 24th of May, were exarhined and calcu-
lated with the fame care as the preceding. On this occafion
there was an obfervation alfo at Florence, the refult of which

ave 6 more in time in the difference of meridians between
that city and Paris, as deduced from the firft occultation.

The error of the tables of M. de Burg was,

In longitude — - - + 4!
In latitude - - --e

On the 1ft of September C. Mechain read in the fame fit-
ting a notice on the new comet which he difcovered at the
national obfervatory on the evening of the 28th of Auguft in
‘Serpentarius. It was not vifible by the naked eye: it refem-
bled two nebulous fiars which are-in the fame conftellation a
little below the equator, and from which it was diftant only
fume degrees towards the fouth, The centre of the nee

ity

7

a

Dr. Olbers’s Planet. 195

fity feemed a little more luminous than the reft; but no fen-
fible nucleus was diftinguifhed, nor any trace of a tail, After
that period the light of the comet always decreafed, becaufe
it was removing from the earth. Its apparent motion in de-
clination, which was at firft 2% degrees towards the north, in
24 hours, was not more the laft day than 30 minutes. The
motion in right afcenfion amounted towards the end to no
more than 17 minutes in 24 hours. The fucceffive decreafe
of the light of the comet, and the brightnels of the hight of
the moon, did not allow of its being obferved any longer. It
traverfed the conftellations of Serpentarius and Hercules.
During the 36 days it was vifible he determined its pofition
on 23 different days; and from his own obfervatjons he eal-
culated the elements of its orbit as follows: they have no re-
femblance to thofe of any of the preceding comets :
Perihelion diftance 10942046; the mean diftance of the earth
from the fun being fuppofed 1-0.
Paffage of the perihelion Sept. 9, 1802, at 20h. 43%/ mean
time at Paris.

Place of the perihelion in the orbit orahiy mae ap tg
Longitude of the afcending node - Io 10 162
Inclination of the orbit - - ‘57 (OF;

Motion—direét.

This comet is the 94th with the elements of the orbits of
which we are acquainted, and the thirteenth difcovered by
C. Mechain. It was obferved on the 26th of Auguft, or two
days before, by C. Pons of Marfeilles; but on thefe two days
the fky at Paris‘ was overeaft. Dr. Olbers difcovered it alfo
at Bremen on the 2d of September. C. Meffieryour fellow-
labourer, and C. Bouvard, adjuné of the board of longitude,
obferved it with great affiduity after the appearance of it-had
been announced by C, Mechain. ;

We fhall give here only four pofitions determined by
C. Mechain; the firft, the laft, and the two intermediate
ones: all the reft will be publithed in detail in ‘the next vo-

lume of our memoirs.

_ SS
Mean Lime Apperent ngut Apparent De-
at Paris, _ Afcenfion. |

clination,
Aug. 28,1802) 9" 44! 30"| 249° 19/ 68” | 6° 8’ 52” S
iO 2 34) 25% 47’ ar.1.9 41.17 N

B 3l 42.1255, 3 5 \24 18 50
[HO | 27,5 1959. 8%, 57) 135, 23,39
—_—_—_—_—nse oo ee | eo ee eee eee
Apparent mo-| 0 42 TO, +2 59 |4I 32 31
tion in 36 ria - Towards the | Towards the

| | eat LT North

The

176 French National Inftitute.—Terrefirial Refraction.

The planet which we announced in the account of the la-
bours of the laft quarter, difcovered by Dr. Olbers, of Bre-
men, has alfo engaged the attention of all aftronomers.

It was obferved by C. Mechain till the 28th of: Auguft,
and a fufficient number of its pofitions was obtained to de-
termine the elements of its orbit in fuch a manner as to en-
able us to find it again fome months hence, when it will ap-
pear in the morning after iffuing from the rays of the fun.
C. Burckhardt, adjun& of the board of longitude, prefented
fome to the clafs, which he calculated, taking into account
even the perturbations which this planet experiences from
the principal part of the reft. Thefe elements reprefent very
well all the obfervations hitherto made. C. Vidal, director
of the obfervatory of Touloufe, placed under a fky fo favour-
able to aftronomy, followed the planet of Olbers with the
fame attention and conftancy which he employed in the ob-
fervations of Mercury, which are fo difficult; and he fent to
the clafs forty, with a table containing twenty-three felect
determinations of its right afcenfion and decllnation, and a
chart of its apparent route from the 19th of May to the 23d
of Augutt. roi.)

In this period of time it. paffed over about 17 degrees in
night afcenfion and 5 in declination.

It appeared to C. Vidal as a ftar of the ninth magnitude,
and exhibited no trace of that nebulofity with which comets
are always accompanied.

NATURAL PHILOSOPHY.

Odfervation of a remarkable Phenomenon of Terreftrial Re-
Sfraftion.

The moft remarkable of the phyfical phenomena next to
thofe which infpire moft men with terror, are thofe fingular
appearances which are produced fometimes by the reflection
or réfraction of parts of the atmofphere, and towards which
the attention of philofophers has been direéted by the ob-
feryations of C. Monge. * eae Mta«

This circumftance reminded C. Dangos of an effect of ter-
reftrial refraétion which he witnefled at Malta in'1784.

On the 20th of March, about one in the afternoon, he
learned, by loud fhoutss which refounded from all the ftreets
of the town, that a new ifland had arifen in the channel of
Malta. Having afcended to one of the terraces of the ob-
fervatory, he indeed obferved a very white tract of Jand in
the middle of the water, the form of which was nearly that
of aright cone irregularly truth The (U1 sCeeummmto
complete, that fome of the failors had refolyed "10

° gO and re-

—_—_—_-—-

Academy of Dijon. 177

connoitre this ifland in order to take poffeffion of it. Tts
figure, colour, and particularly its fituation, in the line
which joins Malta and Mount Aitna, made C. Dangos foon
perceive that it was nothing elfe than the appearance of the
{ummit of that mountain, always covered with fnow, which
fome extraordinary caufe had brought confiderably nearer,
lowering it at the fame time very much below the level of
the water.

The publicity of this phenomenon did not permit
C. Dangos to obferve it with more precifion. A multitude-
of curious fpeétators, whom he could not get rid of, crowded
the terrace. But this aftonifhing fpeCtacle appeared again,
on the 17th of April 1785, at fix in the morning; a time
when the indolent, not being awake, could not interrupt the
diligent philofopher in his retreat.

On this occafion, the apparent ifland, which was better
defined than that of 1784, feemed to be 15’ 177 below the
horizon, which correfponds to a diftance of about 18000
yards: it feemed then to recede and to rife up; after which
it became confufed for a moment, and A®tna re-appeared in
its real place. The coatts of Sicily, which had been hitherto
concealed, were fully feen, and remained vifible during the
reft of the day.

C. Dangos, without attempting to explain this phzno-
menon, thinks that the humidity of the atmofphere, of which
he that day perceived very fenfible figns, had a great fhare in
it; and that.obfervations of the hygrometer ought not only
to be added to thofe of the thermometer and barometer to
determine the refrangent force of the atmofphere, but fome
day may fupply the place of each other.

Going back to the beginning of the laft century, we find,
in the memoirs of the Academy of Sciences, ‘‘ that the
mountains of Corfica, feen from the coafts of Genoa and
Provence, feem at certain hours to plunge into the fea.’’
The author of the memoir which we here analyfe, faw the
fame appearance when at the Ifles d’Heyeres in 1778: but
sth phenomenon was not fo well defined as that which he
relates.

[To be continued. ]

ACADEMY OF DIJON.

In the public fitting on the 6th of September laft, this
fociety, after adopting the plan of its labour and fixing the
nature of its occupations, thought proper to change its title
into that of Academy of the Sciences, Arts, and Belles- Lettres.
It was of opinion that this denomination, more general and

Vou. XIV. No. 54. M more

178 Explofions in Gunpowder Manufaéories.—Bleaching.

more éxpreffive, would preferve much better the remembrancé
of that illuftrious'atlociation to which it has fucceeded, and
in whole fteps it propofes ‘to tread,

C. Lefchevin read a report on the difcovery of the phe-
nomenon of feitillation by the collifion of charred wood.
Three fuccefiive explofions took place in the courfe of four
months in the powder manufactory of Vonges, notwithftand-
ing all the precautions employed to avoid them. The fre=
quent return of thefe events inducéd eovernment to fend to
the fpot C. Lemaitre, infpeétor-general, to inquire into the
caufe of thefe accidents. Having affured himfelf that no part
of the miachmery was deranged, and that no foreign fub-
ftance liad been mtroduced into the mortars, he endeavoured
to verify the fuipicions entertained in regard to the employ-
ment of charcoal in fticks. He recollected, that under cer-
tain circumflances he had obtained {parks by the collifion of
charred wood: he therefore made a'trial, and, after three or
four ftrokes, excited three firong fparks. This fact ferves to
accéunt for the explofions ; it explains why they do not hap-
pen more frequently, and points out in what manner explo-
fions may be totally prevented, by adding one caution more
to thofe already employed, namely, to pulverize the ‘char-
coal ufed in the manufaCtory of gunpowder *.. C. Lefchevin
terminates his memoir with the following reflection :—
“* Heat and light difengaged from a combuttible body being
the more abundant as the combination of oxygen with the
body is ftronger in a given fpace of time, it feems to re-
fult from the different circumftances of the phenomenon I
have deferibed, that a very flight degree of heat only is re-
quired to eflect the combination of oxygen with charcoal, and
the combuttion of the latter.’

C. Potel, in @ memoir on bleaching, communicated to
the fociety interetting details refpecting the new method fub-
fiituted for the old one for bleaching linen, &c. He exa-
mined the different agents which have been recommended
for fome years paft; gave an account of the refult of the ex-
periments he tried to afcertain the value of each of them;
and concluded his memoir by pointing out the moft advan-
tageous; fuch as odorous oxygenated muriatic acid and
cauflic alkali in vapour, which are thofe employed in his
eftablifhment. He fhowed that the ufe of /ulphuret of lime
without any mixture 1s abfolutely improper for bleaching ;
and how ill-founded is the fear of thofe who reject the new

* Jn mott of the punpowder manitfuétories in England, if not in all
of them, the praétice, we believe, has long been to pulverize the charcoal
alone: yet explofions full také place—Evivor.

procefs

Cure for Afphyxia—Acetous Fermentation. "9

Procefs becaufe they fay it Burns the cloth. He proved that
f the operation is performed by an intelligent and careful
artift, the cloth gains inftead of lofing. The author ac-
knowledges that in thefe different proceffes the agent is al-
ways the fame, namely, oxygen, which combining with the
colouring principle renders it foluble in the leys employed,
which then become much more effectual.

The ufe which C. Potel made of oxygenated muriatic acid
Bas conduéted him by accident to many trials and experi-
ments which are of the utmoft importance. He has difco-
vered that this fubftance may be employed with the greateft
advantage in all cafes of a/phyxia. Several rats which had
been found drowned, were placed on a table on which fome
of this gas was depofited: foon after the rats difappeared, and
concealed themfelves in a corner of the room, except one
which remained in the neighbourhood of the apparatus: it
had been reftored to life, but, having fuftained fome injury in
its feet, it was not able to follow the reft. C. Potel caught
thefe animals, reduced them again to a ftate of afphyxia,
and, having fubjeéted them to the ation of the gas, faw
them refufcitated before him. He repeated the experiment
with the fame fuccefs in cats: in the laft place, in imitation
of Dr. Storch, who tried on himfelf the action of hemlock,
this young chemift was induced to try on himfelf the efficacy

of his new method, and his boldnefs was crowned with fuc-
cefs. The academy has appointed commiffioners to afcer-

tain in a certain manner the property of this gas in cafes of
afphyxia.

C. Degouvenain gave the refult of a great number of ex-
periments he made on acetous fermentation, and which led
to the demonfiration of two points in theory not before

roved by any pofitive fact; one of which, when the author
publithes his proceffes, will ferve as a guide to thofe defirous
of making good vinegar. In the mean time he has applied
ie difcovery to the advantage of domeftic economy; and
eing convinced that the efficacy of aromatic vinegar, de-
nds much more on its acid nature than the aromatous
ubftances with which it is accompanicd, he made fome
whieh to be faturated required from 130 to 150 parts of pot-

afh in a thoufand, whereas the ftronge{t before known (that

of Maille) abforbs only 114.
_ Good wine combined with oxygen by a feries of ingenious

ia peculiar to himfelf, is the only fubftance he employs
‘

or making vinegar; and the refult, according to the report of
the commiffioners of the academy appointed to examine it,
is, that it is in every refpeét fuperior in quality to the moft
| M2 celebrated

180 ; Vaccine Inoculation.

celebrated hitherto known. This vinegar may be carried to
any country, and will keep any time without fear of alteration.
It pofleffes alfo another advantage, which is, that it cofts
only half as much as that known under the name of Maille.

XXIX. Intelligence and M, i/cellaneous Articles;

VACCINE INOCULATION.
Dr. Pearfon’s fecond and laft Evidence.
Mercurii, 14 Aprilis, 1802.
Admiral BERKELEY in the Chair.

Dr. PEARSON was called in and examined, and ftated,
that Dr. Heberden * authorized him to {tate, on the authority
of Dr. Lind, and Mr. Battifeombe of Windfor, that there is
now living near Windfor a perfon (the fon of an apothecary,)
who many years ago was inoculated for the cow-pox.

Did Dr. Haberdet inform you whether this inoculation
was performed from one human being to another,. or from
the virus taken immediately from the cow?

A. This is a queftion I cannot anfwer. ar)

What further facts do you know affecting Dr. Jenner’s
elaim of being the promulgator, or inventor of vaccine in-
oculation ? ;

A. [ have admitted Dr. Jenner was the gentleman whe
firft fet on foot the inquiry into the advantages of the vaccirie
inoculation ; but I apprehend that the praétice of vaccine in-
oculation, which was firft promulgated by Dr. Jenner, has
been eftablifhed almoft entirely by other practitioners, and that
his new facts, or what I confider to be new, have been, in
my opinion, difproved by fubfequent obfervers ; and that in
confequence of thofe faéts being difproved, together with the
very extenfive experience of other perfons, we owe the pre-
fent practice of the vaccine inoculation.

Will you inform the committee who thofe practitioners
and perfons were to whom you refer ?

A. The cow-pock inoculation, after Dr. Jenner’s book was
publifhed in May or Jane 1798, which contained feven or
eight cafes, (the whole refult of his experience,) was not
practifed by any perfon, that I know of, till January 17993
neither Dr. Jenner, nor any other perfon that I could find,

being in poffeflion of matter: but in January 1799, in con-

= See Dr, Heberden’s Evidence, annexed to this of Dr. Pearfon.
, fequence

Snes As,

Vaccine Inoculation. 181

fequence of a general inquiry, which I had inftituted imme-
diately after Dr. Jenner’s publication, information was given
of the cow-pock difeafe breaking out in two of the cow ftables
near London; and from thefe fources Dr. Woodville and
myfelf colleéted matter, by which, in the courfe of about
three months, not fewer, I think, than about 300 perfons
were inoculated, in addition to the feven or eight cafes of
Dr. Jenner, then the whole ftock of facts of inoculation be-
fore the public. Befides carrying on the inoculation our-
felves in this manner, we difleminated the matter through-
out the country, in particular to Dr. Jenner * himfelf; and
particularly alfo, I within that time iflued a printed letter,
direéted to upwards of 200 practitioners in different parts of
the kingdom, containing thread impregnated with cow-pock
matter. In the courle of this practice we already Jearnt that
young infants might be inoculated with fafety ; which I ¢con-
fidered to be then a new fa&, Dr. Jenner not having had the
experience, and being apprehenfive of ferious ¢ confequences
from inoculating them.

Secondly, That the inoculated arms, fo far from requiring
eau(tic or efcharotic, or other topical applications, according
to Dr. J, were fooner cured than in the inoculated {mall-pox :
That Dr. Woodville’s publication, in June 1799, appeared,
containing the cafes of upwards of 400 inoculated, up to that
time: and in Augult 1799 I publifhed a ftatement of inocula-
tion, referring to many practitioners who had turnifhed me
with’reports of inoculation with matter which I myfelf had
furnifhed: among thefe I beg leave to mention Mr. Relfon, of
Seven Oaks; Dr. Mitchel, of Chatham ; and Dr. Harrifon’s
cafes; as communicated to me by the right honourable fir
Jofeph Banks: and by that time I had alfo introduced it into
the army, through the hands of the furgeon-general, Mr,
Keate ; and reports frequently came into my hands, by his di-
rection, from the army. I had alfo by that time introduced
the vaccine inoculation into many parts of ihe continent, and
received reports of the fuccefsful practice of it; 1 particular,
from Dr. De Carro, of Vienna. In addition to thefe tefti-
monies contained in the paper above alluded to, is the refult
of my own practice in three parifhes of poor people inocu-
Jated under my fuperiniendance ; fo that im ugat paper, L be-

© See Dr. Jenoer’s Letter in Dr. Pearfon's Inquiry 1798, in which he
fivs no matter can be had. Dr. Jenner, both in letters to Dr. Woodville
and Dr, Pearfon, owns this matter excited the genuine cow-puck.—ore
of the Evidence,
+ This is alfo acknowledged in Dr. Jenner's Letter te che Evidence in
Bebruary 1759,
M3 lieve,

182 Vaccine Inoculation.

lieve, it will be found that 2000 cafes had by that time been
afforded for the public by Dr. Woodville and tmyfelf, and
the perfons with whom I was in correfpondence, and who
are mentioned in the papers alluded to. By this time, too,
fame difficulties appear to have been removed which had
been occafioned, in a great meafure, by fome faéts ftated to
the public by Dr. Jenner. In particular, 1 publithed expe-
riments of inoculation in the paper alluded to:—1ft, Of in-
oculating perfons with the cow-pock who had undergone the’
fmall-pox, to fhow that they could not‘take the cow-pock
after the fmall-pox, contrary to Dr, Jenner: adly, Experi-
ments to {how that perfons could not take the cow-pock bowl
locally and conflitutionally who had already gone through
the cow-pock, alfo contrary to Dr. Jenner: 3diy, Many per-
fons had by this time made experiments to fhow that the
cow-pock did not originate in the greafe of horfes’ heels, as
Dr. Jenner had aflerted. Thefe fentiments will be found in
a printed flatement, which I beg to deliver in as publithed
by me. ,

vi the {pring of the year 1799, whilft the above-ftated evi-
dence was colleéting, a fecond publication appeared from
Dr. Jenner, adding nothing but a few cafes of inoculation
further of the cow-pock, but recommending cautiic or ef-
charotic applications to the inoculated parts in the cow-pock,
not found neceflary by myfelf or the medical perfons alluded
to in my evidence: and 1 confider that the diftinétive cha-
racters of the cow-pock were underftood better by fome of
the above alluded to perfons than by Dr. Jenner.

The vagcine inoculation was next confiderably eftablithed
by the Cow-pock Inftitution, of which I was one of the
founders, the arrangement for which commenced at the very
clofe of the year 1799; which Inftitution has been the prin-
cipal office, I apprehend, for fupplying the world in general,
and the army and navy in particular, with matter; and where
a regular regifter is kept of each of the cafes inoculated, more
fully and accurately than had been done any where before or
fince that time ; where the authenticity of the cafes, from
the nature-of the inftitution, is eftablifhed in a manner that,
T apprehend, will be confidered as unexceptionable. This -
appears from a regifter of above 700 cafes already entered,
and open to the in{fpeétion of the fubferibers. By this time,
namely, the .clofe.of the year 1799, I think I can make it
appear that about 4000 perfons have been inoculated by Dr.
Woodville, myfelf, and correfpondents, which can be referred
tu. I here clofe my evidence, as I confider it of very {malt
importance, comparatively, what was done by others gi

: this

“>=

Sa fain

Vaccine Inoculation. 183

this time, all the faéts that I recollect. of ufe in praétice
being by this time eftablifhed, as they have been fince con-

-firmed.

Did you never hear of inoculation having been performed
by Mr. Cline *, with matter furnifhed by Dr. Jenner, pre-
¥ious to the time you began to praétife vaccine inoculation ?

A. I cannot recollect diftin€gly.

Were not feven or eigit cafes of Dr. Jenner alluded to by
you, cafes of inoculation from one human being to another ?

A. Some of them were; fome were not.

Had not many, or a large majority of your firft cafes, va-
riolous-like eruptions ?

A. The matter, which had never been in the Small-pox hof-
ital, and which I myfelf took from the cows at the two cow
ables above alluded to, fcarcely ever afforded any eruptions
like the fmall-pox; but when | obtained matter to fupply
my correfpondents in the country, not having enough of
my own, but obtaining it from the Smalj-pox hofpital, it
frequently, according to the reports of my correfpondents,
and in a few cafes where I ufed it myfelf, did produce fuch
eruptions,

Was not the matter, or virus, which you diftributed, found
great fault with on account of the eruptions it produced?

A. Mo, it was not found fault with; but many people were
difappointed, as they expeéted that one of the advantages at-
edit the inoculation was to be exempt from the eruptions.
~ Did not thefe eruptions, which were produced by «your
matter, very much difcourage practitioners and the public,
and very much retard the progrefs of the new inoculation?

A. I fhould think it did not.

Do you not know there is a cafe in Dr. Jenner’s+ firft publi-
cation of his having inoculated a child of eleven months old?

A. I believe there is one cafe.

Did not Dr. Woodville and yourfelf take the vaccine mat-
ter in Gray’s-inn Lane, for the purpofe of commencing your
experiments, from a perfon fally marked with the finall-pox ?

A. No fuch cafe is in my recolleclion.

Have thofe facts ftated by you to militate againft Dr. Jen-
ner’s declared opinions remained uncontradicted by him ?
Does he fiill maintain them, or has he publicly retracted
them?

A. [ think he has not retraéted them, (Withdrew.

® The Evidence afterwards found there hat heen a fingle cafe, but
from which no one had any benele by matter, hor was it publifhed till
the following year.

t Sce note, p. 181, on the inoculation of infants.

M 4 Dr.

184 Vaccine Inoculation.
Dr. Heberden’s Evidence.

Dr. Heberden, being called to fpeak to the flatement made
as above written, faid, ‘* That all he knew upon the fubjeét
was, about three years ago Dr. Lind, of Windfor, mentioned
to him, in converfation, there was living, near Windfor, a
young man, apprentice to an apothecary, who, when a child,
was inoculated with vaccine matter by his father, who was
an apothecary in the weft of England. With refpeét to Mr.
Battifcombe he could not fpeak, having heard nothing of it.’*
—On this extraét, from the minutes of the committce of the
houfe of commons, the following remarks have been pub-
lifhed: ‘ In his (Dr. Pearfon’s) examination of the 14th
(April) the authority of Dr. Heberden is made ufe of ta
prove what on that gentleman’s examination was found
completely erroneous, for he could not [peak to what Dr. Pear-
fon afferted he could; and of Mr. Battifcombe he had no know-
ledge. On this it is unneceflary to make any comment; the
conclufion muft be obvious.”

Thefe affertions, made from the words of Dr. Heberden’s
evidence, muft appear unwarrantable by merely publifhing
this gentleman’s explanation fubjoined, obligingly commu-
nicated at the requeft of Dr. Pearfon, who is confcious that
he had been fufficiently correét in the ftatement above given
on the authority of Dr. Heberden.

‘¢ Dr. Heberden acquie{ces in the correétnefs of his printed
evidence, with the addition of only two words, viz. “ having
heard nothing of it from him.”’ In faét, Dr. Heberden was
acquainted with Mr. Battifcombe, but received his informa-
tion refpeéting the vaccine inoculation from another quarter.
Still it is true, that when Dr. Heberden mentioned the cir-
cumftance to Dr. Pearfon upon Dr. Lind’s authority, he cor-
roborated his {tatement by adding, that Dr. Gifborne had
been made acquainted with the fame account through Mr.
Battifecombe. So that Dr. Heberden may, in effect, be faid
to have related the circumftance to Dr. Pearfon upon the
united teflimony of Dr, Lind and Mr, Battifcombe ; though,
his information in the latter cafe not having been derived
immediately from that gentleman, he could not, with pro-
priety, produce to the committee the authority éf Mr. Bat-
tifcombe for what he had heard upon the fubject.””

How to inoculate feveral hundred Perfons with the Matter
of a fingle ordinary Vaccine Pock.

A member of the Vaccine Inftitution mixed the fluid of

a fingle cow-pock with a drachm meafure of water of about

the

SE

The Planet.of Olbers. 185

the temperature of 70° of Fahrenheit. Of three fubjeés in-
eculated with this diluted matter, two took the difeafe in the
ufual way. ‘The remaining third was inoculated in each arm
with one puncture with this diluted matter, and alfo in each
arm, in like manner, with undiluted cow-pock matter ; "but all
thefe four punctures failed to produce the vaccine difeafe, the
{ubject being an adult, and probably had had the fmall-pox.

Letters from Baffora of the 17th of June, from S. Mairefty,
the Britifh conful at that place, and Dr. Milne, phyfician to
the factory, addrefled to Dr. De Carro, of Vienna, confirm
the happy refult of the vaccine inoculation, which has been
introduced into feveral parts of the Eaft by the zeal of Dr.
Carro. ‘This beneficial practice has been introduced not
only at Bagdad but alfo at Baflora. At the latter the con-
{ul fet the firft example by caufing his own fon to be inocu-
lated; and from the end of April to the 27th of June the
operation had been performed on forty fubjects with the
beft fuccefs. Dr. Milne inoculated not only the failors on
board fome fhips deftined for Bombay, but fupplied a mer-
chant who was travelling to Mafcate with vaccine matter for
that diftrict,

THE PLANET OF OLBERS.

Circumftances have been much more favourable for deter-
mining the orbit of this planet than for that of Piazzi, an
arc four times as large. A great number of obfervations
made during fix months, with great exactnefs, notwith{tand-
ing the difficulty of obferving {fo faint an object, and an in-
clination of orbit much more confiderable, give more pre-
cifion to the refults of calculation.

C.,Mechain and Meffier obferved this planet till the mid-
die of the month of Auguft; the former, with a telefcope
which was not even mounted on a parallactic machine,
which greatly increafes the difficulty of obfervation. The
comet which ©. Mechain then difcovered having obliged
him to interrapt his obfervauons, C. MefGier continued to
oblerve it alone till the 24th of September: he even tried to
obferve it on the 6th of Oétober; but the vicinity of the
horizon, and particularly the {moke of the chimneys which
furrounded the obfervatory, rendered the obfervation too un-
certain to be turned to any ufe. All thefe obfervations agree
with an uncommon precifion, and far fuperior to what could
have been expeéted from an equatorial feétor; C. Lalande
having found the difference of 30// in two confecutive
obfervations of Mercury made with a large equatorial fector
by an able afironomer ; it appeays alfo that this planet has no
where been obferved fo long as at Paris,

I have

186 Travifit of Mercury.

I have again. carefully calculated the perturbations of 'the
new planet. They are exceedingly numerous; neverthelefs
I have obtained only an approximation very far diftant. from
that perfection to which aftronomers afpire. The applica-
tion of fo many equations to calculation is attended with fe-
veral difficulties, and requives many trials, principally on ac-
caunt of the great inequality. I have not yet finifhed them,
but I hope it will be a gratification to aftronomers to be
made acquainted with the primitive orbit which I had-cal-
eulated without employing perturbations, and corrected
according to the lateft obfervations ; a labour which was in-
terrupted only for two days by the refearches. 1 began em-
ploying the perturbations—

Node 172° 27°35 ~—1inclination 34° 38/0//—longitide of the
perthelium 121° 127.197/: onthe 4th of April 1802, its
motion + 2°3” per day.

Mean anomaly, April 4th, at 10h. 51/19/”, 42° 21/9”,

Great femi-axis 2°769915 3 eccentricity 0°2463.

Sidereal revolution 1683 days 20 hours.

Thefe elements repreient the five obfervations imthe fol-
lowing manner :

Errors Apr. 4. Mav 20. July 3. Aug..g. ‘Sepi 20, /
Helioc. in long, + rg! + rod? 21-64% ~0'6" —6°0”
in lat. OO = 3:7, = 35. 4 13°5 —183
Geoe..in lat, - - - +11. -12

Obfervers—Von Zach, Lefrancais-Mechain, Mechain,
MefGer, and Burckhardt.

With thefe elements it is found that the planet on the
4th of Feb. 1803, at midnight, will have 267° 41° right af-
cenfion, and 5° 38° north declination ; which differs only a
few minutes from the pofition which Dr. Gaufs yaa
from his elements. That able aftronomer could employ ob-
fervations only to the 8th of July, and ftill propofes to rectify
his elements by later obfervations.

I hope this refult will be confirmed when I have deters
mined an ellipfe by employing the perturbations.

a he) BurckHaRrpDt,
Nov. 13, 1962. of the Bureau of Longitude,

TRANSIT OF MERCURY OVER THE SUN.

The weather on the oth of November was favourable to
the withes of aftronomers, who had an excellent opportunity
of obferving this phenomenon, lor the information of our
philofophical readers we prefent them with thofe obfervations
of the tranfit which have reached us. , In a fature number
we fhiall give other details refpecting ite

Cirecht,

, Tranfit of Mercury. 187

Utrecht, Nov. 10.—M. van Utenhoven obferved yefterday
at the obfervatory of this academy, the ingrefs of Mercury
at 12 hours 17 minutes 53 feconds, and the egrefs or the end
of the tranfit of the planet over the fun’s difk at 19 hours
19 minutes 28 feconds true time. © M. Timmers of Rotter~
dam, a ftudent here, obferved the paflage of Mercury over
the meridian to be 15 fecondsvafter the fun’s limb. He ob-
ferved alfo feveral tinies the contaé of the Sun and Mercury
on the horizontal and vertical threads of a quadrant by Bird,
in order to calculate the time of the conjunétion according
to the method of L’Ifle le Cadet. This phenomenon, which
will not be vifible again in this republic till the 4th of May
1832, was rendered much more important by the appearance
of a great many folar {pots ; a collection of fuch {pots, one or
two of which feemed to be larger than Mercury.

Leyden, Nov. 10.—Yetterday morning | had the fatisfac-
tion, with M. Bifdom, M. van der Meer, and feveral of my
pupils, to obferve at the obfervatory of our univerfity the
paflage of Mercury over the fun’s difk. Mercury it appears
mut have been onethe fun’s difk before fun-rife, as the clouds
prevented us from feeing that luminary till half after nine.
‘The fun having then broke through the'clouds for fome time,
the planet was plainly feen on the fun’s difk as a black,
round, fharply defined body, and could be eafily diftinguithed
from the folar {pots, a great many of which were then vifible
on the fun’s di{k. The planet took its courfe under a great
many of the principal {pots, and, when it approached the
fun’s limb, feemed to have a fomewhat elongated form. If
obferved the contact at the time of ingrefs to be at 12 hours
15 minutes 6 feconds, and at the time of egrefs at 12 hours
16 minutes 40 feconds, and therefore that of the planet’s was
12 hours 15 minutes 53 feconds, true civil time. The
planet employed 94 feconds from the time of ingrefs to that
of its egrefs, which agrees very well with calculation if the
diameter be taken at 17 feconds, 1 previoufly obferved the
planet’s paflave of the meridian with our meridian circle on
the 8th of November, 23 hours 43 minutes 8 feconds mean
time. I have no doubt that this tranfit will enable aftrono-
mers to improve or confirm the tables of Mercury.

Van Berck CALKOEN.

Enfchede, Nov. 13.—Obfervation of the tranfitof Mercury
over the fun’s difk at Enfchede on the gth of Novem-
ber 1802, with the day: telefcope and an achromatic tele-
feope, which magnifies the diameter 50 umes, the clock
being brought to true time by a meridian line: bat there

was

188 Tranfit of Mercury.

_ no opportunity for taking correfponding altitudes of the
. fun.

Enfthede lies 50° 16’ north latitude and 7/30” in time
eaft from Amfterdam. At fun-rife I faw the planet a good
way from the eaftern limb on the fun’s difk. There were a
great many fpots on the fun’s difk, and particularly on the
weft fide, about :o in the morning. The {ky was clearer,
though it was cloudy in the weft. We were, however, able
to follow the planet in its paflage. About 11 the fky be-
came clear in the fouth; but about 10 minutes after noon a
very thick cloud proceeded from the north, which threat-
ened to deprive us of all hope of fecing the egrefs. A few
minutes before the planet came in contact with the fun’s
limb, [ took the fmoked glafs from the telefcope, and faw
clearly the interior contaét of the fun’s limb, at 12 hours
22 minutes io feconds true time; but in-a few minutes the
weftern limb of the fun was covered by a thick cloud, fo that
no obfervation could be made of the exterior contaét of Mer-
cury with the fun’s limb.

The planet when on the difk feemed to be furrounded by
a {mall luminous circle. The fun’s limb alfo at the time of
imterior contaét feemed to quiver, and, as it were, to fwell up
a little. L. NIEUWENHUIS.

Paris, Nov. 9.—The paffage of Mercury over the fun’s
difk was obferved this morning, for the 19th time. The
weather was exceedingly favourable, and aftronumers en-
joyed, in the completeft manner, the fight of this curious
phenomenon. I was the more anxious to have a view of it,
as I -fhall never fee it more, fince the next will not take place
till the 5th of May 18323 for [ do not reckon thofe which
will be invifible in Europe. I had the fatisfaction of ob-
ferving it in the fame place where it was obferved for the firft
time, Nov. 7th, 1631, by Gaffendi, one of my moft illuf-
trious predeceffors in the Collége de France. Mercury
emerged from the fun at 8 minutes paft noon, which agrees
to a minute with my tables of Mercury, on which I have
been employed for forty years. That day, remarkable to af-
tronomers, is much more fo on account of the regencration
of France. LALANDE.

From a Corref/pondent.
STR, :

If the fubjoined fketch and account of Mereury’s tranfit on
the gth inftant, and bis contaét with the penumbra, or light
part of the largeft {pot on the fun that day, be worth infert-
ing in vour valuable Magazinc, the infertion may perhaps

5 lead

a

.Tranjit of Mercury. 189

Jead to further difquifition, and'will much oblige a lover of
aftronomy, who i3 a conftant reader of your hilofophical
Magazine *,

Apparent Time.

Firft conta& with the light part at @ Sur mae oe
Central contact - - wt er ae Os
End of contact - - hid. lls alle 5
Firft conta of Mercury with the fun’s limb 11 57 +13
Central contact ~ - = te RY
End of contact . - Me hie ey 17

Mr, Tilloch, .

~° From another Corre/pondent.

Nov. 8, 1802.—At 20h. 15’ apparent time, haying fitted
a prifmatic dark glafs to an achromatic telefeope of Dol-
lond’s, magnifying about 65 or 79 times, [faw Mercury upon
the fun’s difk, extremely diftinét, and well defined. As Mer-
¢eury was then approaching very faft towards the fun’s centre,

This correfpondent is requefted to furnifh us with the longitude
and latitude of his obfervatory, the method by which he afcertained his
time, and the nature and power of the tglefcope he made ule of,

es and

196 Tranfit of Mercury.

and the body of the fun appearing pretty fteady, I begat to
take fome diftances with a micrometer I had previoufly ap-

lied to the telefcope for that purpofe. Upon trial, however,
I found the fun’s limb fo very tremulous, that I could take
but few meafures fo fatisfactorily as I wifhed: thofe which I
can chiefly depend upon, I have here fele&ted and reduced,
by which it appears the ncareft approach of Mercury to the
fun’s centre, was at 2th. 13’ 38’ apparent time, when Mer~
eury’s centre was 59°8”’ north of the fun’s centre.

Apparent Time. Dift. Centres. © & 8
4 [208 56% a6" 58:6"
ar 6 Yo'”9 I irr
or 8 95's T
es Ae po 2. 40°F
aI 45 29°2 ee
21 46 163 3 19°0
oi a 3 40.4
Internal contact = - — sats" 56! 58/7) 2
External conta&t - at 23 58 35'1 apparent time.

The above times and obferved diftances are reduced to the
meridian of St, Paul’s church, latitude 51° 307 49”, long.
23°17 welt.

The internal conta& was alfo obferved in long. 19'24.””,
weft lat. 51° 31/47/ at 23h. 57’ 18-8”, which reduced to the
time of my obfervation gives 23h. 57/ 12°9// apparent time.
The gentleman who. made this obfervation informs me that
the houfe in which he was fituated was in fuch a continual
fhake from carriages paffing by, that he could not be certain
of the contaét to Jefs than a few feconds; alfo that the me-
thod by which he got his time was by equal altitudes taken
under the like difagreeable circumftances.

TO THE EDITOR.
Refpected Friend,

* I mutt beg room for a few lines to obviate any offence to a
refpectable body by the erroncous addition of F. L.S. to my
name, which I meet with in p. 55 of laft Magazine. I am
neither fellow nor affociate of the Linnzan Society, and,
notwithftanding the infertion of a little piece, which has
been favourably received by that body in their laft volume of
Tranfaétions, am not, nor have been, a candidate for a place
therein. Thy fincere Friend,
L. Howarpb.
We are forry to have made the miftake alluded to by
Mr. Howard. Ii arofe from a very natural aflociation of
ideasy

i ate Oa ae ee ee

-Galvanijm. 19%

ideas, Which) might eafily miflead.—His partner in bufinefs
Mr. Allan, is a worthy member, and himfelf a meritorious
contributor to the labours of the Linnzan Society.

GALVANISM. Paris, O&. 14.

C. Aldini, a native of Italy, and nephew of the celebrated
Galvani, to whom we are indebted for the difcovery of that
electricity called the Galvanic, repeated, a few days ago, in
prefence of the commiflioners of the National Inftitute, and
yefterday at the Oratoire, in prefence of the Galvanic Society,
the principal experiments; in confequence of which he af-
ferts, with juitice, that the ideas of his uncle refpecting ani-
mal éleétricity ought not to be entirely rejected, to adopt ex-
clufively thofe of Volta refpeCting metallic ele&tricity. It
refults, indeed, from the experiments of C. Aldini, that there

4s‘an animal pile and an animal circle, as there is a metallic

pile and metallic circle.
Therexperiments of which we were witneffes, and which
prove his opinion in a rigorous manner, are as follow:
_ 1ft, The {ciatic nerves of a frog being laid bare, as is ufu-
ally done, for fubjecting them to the action of the arming

and metallic circle, he contented himfelf with bringing to-

gether and putting in contact the mufcular parts of the
thighs and paws of the frog with the uncovered nerves, and
contractions of the animal took place asin the ufual Galvanic
experiment. .

ad, He took the frog by the paws, holding it with one
hand by the mufcular parts, making the nerves hang down:
he touched with a finger of the other band the nerves thus
fufpended ; and the contractions took place as by the metallic
circle and Galvanic apparatus. .

gd, For the third experiment, he made his affiftant hold
the frog by the paws or by the mufcular parts; applied his
finger to the nerves, without giving his hand to the affiltant ;
and the contractions did not take place. He then gave his
hand to the affiftant; and, having applied a finger of the
other hand to the nerves, the contractions took place as in
the other experiments. Thefe experiments were repeated on
feveral frogs. :

In the laft place, feveral experiments were made on the
head of a large dog feparated from the trunk, which had no
relation either to the animal-eircle’or pile ; but afterwards
they took one of the above frogs, and, by putting a finger
into the {pinal marrow of the dog, prefenting with the other
hand the nerves of the frog to one of the mulcles of the oe
7 ©

192 Galvanifin.

of the dog, the contractions of the frog teok place as with
the Galvanic apparatus; which, according to the obfervations
of the author, leaves no doubt refpecting the exiftence of the
animal circle and pile. Thefe ingenious experiments will
doubtlefs furnith to their modeft and Jearned author a multi-
tude of other ideas on the animal economy, particularly re-
{fpecting the nervous fluid, &c., which leave him the care
and glory to explain.

For my part, [ came out from thefe experiments charmed
and tran{ported with admiration at the fimplicity of the means
which nature employs in its phenomena that feem to us the
moft complex. It appears to me proved, that to perform a
prodigious number of its operations it contents itfelf with one
eleCtric fluid, which it puts in motion at the furface and in
the interior of the earth by a kind of Galvanic piles, which
produce, as I have explained in my Jeétures, a great number
of the phenomena of the animal and vegetable kingdom ;
and that it has employed the fame agent in the animal king-
dom, by organizing the nerves and mufcles as Galvanic piles
to execute moft of the operations of animal life by the fame

* agent, and by means of thefe fubftances the nerves and the

mufcles, which it has organized in {uch a manner, that they
difcharge, in regard to each other, the fame functions as the
different metals the contact of which excites a permanent
current of the eleétric fluid; which is the moft valuable dif-
covery for which we are indebted to the pile of Volta.

It had hitherto been tried, without fuccefs, to excite a per-
manent eleétric current without friction; and the machine
of Hierne did not accomplifh this end in a fatisfactory
manner.

This permanence of the electric fluid, for which we are
indebted to the Voltaic pile, is a difeovery, then, no lefs ad-
mirable perhaps than that of C. Aldini; and both have given
to the natural fciences a ftimulus which will aftonifh future
ages, if the refults be followed, as there is no reafon to doubt.

> Masvyver-Din, Profeffor in the
ge Special School of Medicine at Strafburgh.

. ing the impu

[ 193 ]
XXX. On Capillary Afion. ByJoun Lesuie, E/y.*

Tue principle of univerfal attraétion, having finally fub-

dued every {pecies of oppofition, is now fixed on a bafe never

‘to be fhaken. Many are the fruitlefs attempts to explain its

operation by the impulfive energy of fome invifible impalpa-
ble fluid: but thefe owe their birth to metaphyfical prejudice,
and are jufily difcarded by all fober and reflecting inquirers.
Nor is the fuppofition of fuch mechanical intermedia merely
repugnant to the {pirit of true philofophy ; it is direétly con-
tradicted by recent difcoveries. When an impulfe is com-
municated to any mafs or fyftem of particles, it is transferred
along the chain by a feries of pulfations, each particle in fuc-
ceffion feeling the ation and fuffering a momentary derange-
ment, Motion is therefore propagated in the fame manner
as found, and the celerity of its tranfmiffion muft depend on
the mutual diftance of the affected particles and the relative
force with which they are connected together. In moft cafes,
indeed, that come under obfervation, it is impoffible to di-
ftinguith the interval between the origin and the termination
of an impulfe, which is thence very generally imaginad to act
fimultaneoufly through the whole line of its communication.
But, though the rapidity of tranfit outftrips the quicknefs of
our fenfations, it ftill requires a certain lapfe of time. Nay,
on the jut eftimate of this principle,—on the duration of ef-
feét,—(refined as it may appear,) depends the theory of the
tools and manipulations ufed in moft of the mechanic arts.
Nor is the exiftence of fuch a fmall yet finite moment a
mere abftraétion ; it is the neceflary refult of the known pro-
perties of matter. Were we to fuppofe that the fun aéts on
the planets by the interyention of fome fubtle medium dif-
fufed through the celeftial {paces and endowed with the mott
powerful elafticity, a very confiderable meafure of time would
be required to propagate the impreflion. If we afcribed to
that fluid, for RE the relative denfity and elafticity of
hydrogenous gas, almoft five years would be {pent in convey-
live energy to the earth. But it is proved, by
fome late and very nice refearches of M. Laplace on the ir-
regularities of the planetary motions, that the attractive force
of the fun is exerted fimultaneoufly at all diftances. The
notion of an intermediate fluid is thus entirely precluded.
The principle of aétion at a diflance istheretore a primary

EE * Communicated by rhe Author,
Vo-. XIV. No. 55. N and

December 1802.

194 On Capillary Action.

and effential law of nature, Gravitation itfelf is only a branch
of that law, from which are derived the various conftitution
and all the diverfified properties, of bodies. The mutual action
exerted between two elementary portions of matter is, in the
Janguage of modern algebraifts, always fome funétion of their
diftance. At proximate diftances, this function mutt change,
repeatedly, and with different degrees of intenfity, from pofi-
tive to negative, or from attraction to repulfion. Hence the
varied ftructure and compofition of bodies. It is indifferent
whether we confider the elementary portions of matter as
points, atoms, particles, or molecules. Their magnitude, if
they have any, never enters into the eftimate. When the
diftance is confiderable, the law of aétion becomes confounded
with that of gravitation, and is of fuch remarkable fimplicity
as to qualify it for the happte(t application ever made of the
mathematical feiences. Could we afcertain the gradations
at near diftances, we might determine the ftruéture, affini-
ties, and mutual operations of bodies, with the fame cer-
tainty as we compute the revolutions of the planets. But
fuch a difcovery feems placed beyond the reach of the human
faculties. However, by a fcrupulous attention, we may dif-
cern certain inftances of the approximation and tranfition of
corpufeular forces. And I hold thofe faéts to be the more
valuable, as they form the intermediate link between the me-
chanical and the chemical phenomena.

Of this kind I confider the a/cenfion of water and other
liquids in capillary tubes. This fact is fo familiar that I need
not {top to deferibe it. It was firft noticed by the Academy
del Cimento, at Florence, early in the 17th century; but
feems not to have been much regarded in the fequel. After
the promulgation, however, of the Newtonian fyftem, the
fubject was revived with ardour. It was juftly confidered as
affording intuitive evidence of the reality of attraction. About
the beginning of the 18th century, Hawkfbee, in England,
made fome excellent experiments on capillary aétion ; and
Muffchenbroeck purfued the farhe courfe in Holland. Similar
experinents were performed in France; but in that country
the Cartefian philofophy was then in the height of its carcer,
and no deliberate attention could be paid to faéts which ap-*
peared to countenance an oppofite fyitem. About the fame
period Dr. Jurin publifhed, at London, an elaborate differta-
tion on the caufe of capillary action; and his explication of
that curious fact feems, either from conviétion or fupine
acquiefcence, to be almoft univerfally adopted. It is repeated
in all the elementary books of natural philofophy. It con-
tinues to maintain the fame credit: no fufpicion is ever ftarted

of

a

On Capillary AGion. 195

of its folidity, and fcarce an attempt is made to eftablifh an-
other theory. The celebrated Clairaut, indeed, has cafually
touched on the fubject of capillary action in his Treatife on
the Figure of the Earth; but his inveftigation of that phe-
nomenon is loft in a chaos of calculation. M. Lalande, who
is fo a&tive a writer, has tried to unravel it: the aftronomer
does not appear, however, to have fucceeded. I content my-
felf with this general notice of his little traét ; for to refute it
is much eafier than to render it diftinétly intelligible.

But, when we coolly confider Jurin’s account of capillary

action, we are furprifed that it could obtain fuch fuccefs. It
is in appearance fimple indeed, and plaufible; but it will not
bear the flighteft examination. The water is conceived to be
kept fufpended in the tube by the attraction of the fmall ring
of glafs immediately above the interior furface. But I afk,
Ought not the ring 4e/ow to exert an equal force in a con-
trary direction, and confequently deftroy the effect of the
former? This argument it feems impoffible to elude, and to
expand it would be fuperfluous. We muft therefore regard
the common account of capillary aétion as entirely without
foundation.
_ It may well furnifh matter for furprife and mortification to
remark fuch a glaritig overfight committed in the very porch
of the phyfical fciences. But if we extend our obfervations
we fhall foon be convinced that the popular branches of phi-
lofophy, with all their fuppofed improvement, are in general
ftill very defective and erroneous. Thofe flowery departments
have been left to the culture of a fecondary order of men,
whofe imagination was commonly more powerful than their
judgment. In every age the vigour of genius has been di-
reéted to the fublimer parts, and thofe united efforts have
reared a ftupendous monument of the penetration and re-
fources of the human mind.

In attempting to explain the mode of capillary action, the
chief difficulty feems to arife from the prejudice that a ver-
tical attraction is neceffary to account for the elevation of
liquor in the tube: yet this is affuredly not the primary di-

tion of the force; for, the action of glafs being evident]
confined within very narrow limits, that virtue muft be dif-
fafed over the internal furface of the tube, and confequently
“mutt exert itfelf /etera/ly,.or at right angles to the fides, Nor
is it difficult to conceive how a lateral action may caufe an
_afcent. We know that in fluids a force impreffed in one di-
rection is capable of propagating itelf in a// directions. The
tendency of the liquor to approach the glafs, muft e¢cafion it

yaks N32 to

196 On Capillary Aciton.

to fpread over the internal cavity of the tube, and, confe-
quently, to mount upwards.

But let us view the fubje&t a little more clofely. Suppofe
I put a drop of water upon a horizontal plate of glafs: it
will quit its globular form, adhere to the glafs, and fpread
aut till it has covered the plate with a thin aqueous film.
What then is the caufe of this phenomenon? It is furely
not the mere incumbent weight of the water; for that would
not have been fufficient even to furmount the mutual adhefion
of the particles of the fluid, or their natural tendency to ag-
¢lobulate. Befides, the fame precife effe@ will take place if
the drop be applied to the under fide of the plate. The water
therefore diffufes itfelf on the glafs in the fame manner as if
it were urged by the preffure of a column acting againft that
furface. Its attraCtion to the glafs is equivalent to this fup-
pofed preflure, and is productive of the fame confequences,
But why fhould the mere tendency of the water to the furface
of the glafs occafion a difperfive motion? The reafon is, that
the external particles could not approach without {preading
themfelves and extending the film: and analogy will inftruct
us, that the attraction of water to glafs muft increafe in pro-
portion to the proximity of its approach, tll it has reached
the term of clofett union. °

If the plate be held vertically the aqueous film will ftill
adhere, but only to a certain limited elevation, depending on
its thicknefs. I reckon the force of fufpenfion correfpondin
to each inch of width, or of the extent of the bacental
linear boundary, as equal to the weight of about the rooth
part of a cubic inch of water. Hence, if the film was only
the 100oth part of an inch in thicknefs, it would maintain a
height of ten inches; but if its thicknefs amounted to the
10th of an inch, it would fubfide to an elevation of one inch.

Suppofe I now dip the plate perpendicularly in a bafin of
water, the film will fufler a very confiderable modification.
A new portion of water greedily attaches itfelf to the film,
and deprefles it by the load of additional weight. The curve
of protuberance feems nearly an inverted parabola, and con-
fequently the preflure to be fuftained is only the third part of
what would obtain if the column had been of uniform thick-
nefs. The relative force of: attraction is therefore = +353
and if we conceive the height to be equal to the breadth,
which appears nearly the cafe, either of them wil! be denoted
by /;4r, ora little more than the fixth part of an inch:
a conclufion which correfponds fufficiently with» obferva-
tion,

If

» /

On Capillary AGion. 197

Tf two glafs plates, held near each other and parallel, be
dipped in water, the water will mount in the included fpace,
The aqueous protuberance is now confined, and the afcent of
the column is therefore greater; befides that the effect is
doubled by the ufiited action of both oppofite furfaces. Each
furface aéts only upon a thin film; but, fince the force is
fpent in fupporting the particles which adhere to this, the
height of the column mutt evidently be inverfely as the weight
fufpended, or the diftance between the glafs plates. Imagine
the interval between thofe plates to be the 1ooth part of an
inch: then each furface may be confidered as acting again{t
a.columa of the thicknefs of the 200th part of an inch; and
fince the force of attraction is equivalent to the weight of the
1ooth part of a cubic inch, the correfponding afcent muft be
two inches. In like manner, if the interval were only the
200th part of an inch, the height of the column muft be
four inches. In general, put d = the diftance between the

plates, and Sy = the height of the column.

The fame reafoning is applicable in the cafe of capillary
tubes. The attraction of the internal furface is exerted on
a thin circular lining; but this force is diluted and attenu-
ated by the preflure of the water which adheres to the film
and occupies the cavity of the tube. A circle, it is well
known, is equal to a aoa which has the circumference
for its bafe and half the radius for its altitude: confequently
the attractive power of the glafs will produce the fame effect
as if it aéted fimply againft a column whofe thicknefs is one-
fourth part of the bore of the tube. But we have already feen
that the meafure of force is expreffed by +03 and hence, if
4 denote the width of the bore, the height at which the water

will be fufpended in the tube will be = Bed Vi goa Bt

100 X zd 25d.
Thus the altitude of fufpenfion in capillary tubes is the double
of what obtains with parallel plates whofe mutual diftance is
the diameter of the bore.

The fufpenfion of water in capillary tubes muft depend
entirely on the fmallnefs of the fuperior orifice. Nor will
the effeét be in any degree altered, however much the lower
part of the tube be enlarged: for, by the laws of fluids, the
preffure is proportional merely to the altitude of the column ;
and this preflure is balanced at the upper extremity by the
adhefive force of the film, which attaches itfelf to the irfibe

af the tube.
N3 If

198 On Capillary A&tion,

If a capillary tube be inferted through another tube, and
both dipped in water, it will rife not only in the capillary
bore, but in the interftice between the two tubes. Even
though the diameter of the outer tube be confiderable, the
water muft form a fenfible elevation in the intermediate ring;
and this elevation will be determined by comparing the ex-
tent of the oppofite furfaces of glafs with the intercluded fpace
on which their aétion is fpent. The abfolute afcent in the
capillary bore continues the fame; but, if we eftimate it from
the external protuberant ring of water, it will appear evi-
dently diminifhed. Conceive the outer tube to be fitted with
a bottom, and the whole to be removed from the bafin: the
effect will ftill remain the fame, and confequently the appa-
rent altitude of the fluid in the capillary bore will be dimi-
nifhed. Let d denote this bore, d the diameter of the tube,
and d’’ the width of the outer tube, or rather that of the cif-
tern in which the capillary is plunged: then it may be eafily
inveftigated, from the principles already explained, that the

’ stelle ae:
height to which the water will rife is = — (— —
25 d
I ni 2
rapa in inches.

If the tube has its lower orifice not too wide, on removing
it from the ciftern in which it was immerfed, a drop of water
will adhere, and the column in the capillary bore will remain
at the fame height. Its fufpenfion, we have feen, is pro-
duced by the lateral adhefion of the internal film, to which
a cylinder of water attaches itfelf. If the drop at the extre-
mity be diminifhed by any caufe, fuch as the contaét of
bibulous paper, the column will fubfide; for the tendency
of the water to agelobulate then counteraéts, in fome degree,
its capillary extenfion in the tube. Cover a horizontal piece
of glafs with a fine film of water, and bring the tube with
its charge to touch it, the water will immediately defert the
cylindrical cavity and fpread over the film. ‘The attraction
which the vertical column of water, joined to its weight, bears
to the expanfive horizontal film, overcomes its adhefion to
the narrow film that lines the infide of the tube. We here
contemplate the extreme cafe; but it fhould be remarked in
general that the mutual attra¢tion of the particles of water or
other fluids muft, to a certain degree, diminifh their afcent
in capillary tubes, fince that force tends to agglomerate the
parts, and confequently oppofes any ramifications or fila-_
mentous prolongations of the fluid. This refifiance, it might

7 be

On Capillary Aion. T99

be fhown, is, like the capillary aétion itfelf, inverfely as the
width of the bore. The two oppofite effects, being thus pro-
portional, are confounded, and their difference only is ob-
ferved. In the cafe of glafs, the capillary a¢tion greatly pre-
ponderates: one confequence of this is the concavity res
marked at the topof the column; a clear proof that the lateral
exceeds the central adhefion. If the upper {urface were per-
feétly flat, thofe two forces would be in exact eqaiibrium.
But the convexity of the top of the column proves that the
fluid has a greater attraction to its own particles than to glafs.
Such is the cafe with quickfilver, which, inflead of afvending
in capillary tubes, fuflers a depreffion according to the famé
Jaw. This remarkable fact has been aferibed to fome re-
pulfion exifting between quickfilver and glafs. But I regard
fuch a duppofition as equally unneceflary and improbable.
The fame confequence would, no doubt, take place with
water in polifhed tubes of fteel or brafs. If I place a drop of
water on a {mooth furface of metal, or a globule of quick-
filver on a plate of glafs, neither of them will feem at all af-
feéted by the contaét, but will obey the attraction of their
own particles, and therefore affect the {fpherical form.

Hence the mercury in a barometer can never mount to its
true height; and the error will be the more confiderable in
proportion as the tube is narrow. If two tubes of different
diameters be carefully filled and planted in the fame bafin,
the mercurial column will ftand vifibly bigher in the wider
tube. This aberration has been generally neglected, though
it muft evidently affect the barometric calculation of the alti-
tudes of mountains *,

On the fame principle I would explain the familiar experi-
ment “of a needle fwimming on the furface of water. It is
fuperfluous to have recourfe to any fuppofed repulfion. The
internal cohefion of the water oppofes its divifion; a gentle
cavity is formed, which, prefling upwards, fupports the needle.

Above twenty years ago, that able chemift M. Guyton-
Morveau, examining into the nature of chemical affinities, at-
tempted to determine the relative attraction of a variety of fub-
ftances, from the force required to detach {mall plates of glafs
or metal from their contact with water or quickfilver. The

* Suppofe the mercurial column at the bottom of the mountain to be
30 inches, at the fumumit 15; and let the depreffion be equal to the 2oth
of an inch, which correfponds to ordinary tubes,, Then the corrected co-
Jumns are 30°05 and 15°05; butthe ratio of thefe numbers. is different
from that of 30 to 1s, and contequently it will pive a different altitude.

The common calculation will reprefenc the mountain above go feet higher
than it ought to be.

N4 idea,

:

206 On Capillary Adion.

idea, though not logicaliy accurate, was ingenious, atid had &
certain degree of fuccefs. It is evident that the force meafured
was not firiétly that of mutual attraétion, but only the weight
of the protuberant mafs of fluid the moment before its fepa-
yation. Nor does the height of this column depend on its
mere adhefion ; for it can never exceed the cohefive force of
the fluid molecules to each other. When the plate, what-
ever may be its attractive power, is raifed above a certain
limit, the attached column breaks, and part of it adheres to
the plate, while the reft falls back into the body of the fluid.
Thus, thofe experiments can afcertain the adhefion of the
plate only when st is comparatively very fmall ; in other cafes
they meafure fimply the integrant attraction of the particles
of the fluid. If capiflary action be regarded as approximate
to chemical affinity, this may be always determined, with
facility and with fufficient accuracy, by obferving the afcent
in two parallel plates fixed at fome minute but known di-
ftance from each other.

The elevation of a liquid in a capillary bore is produced by
its fpecific attraGtion to the matter of the tube. With dif-—
ferent fubftances the effets are confiderably diverfified: al-
cohol, for example, rifes little more than a third part of the
height to which water reaches. But the flighteft alteration
in the conftitution of the fubftance will fometimes occafion 4
very material difference of effect. Thus I find that, on di-
luting the alcohol, the afeent of the liquor is fearcely at all
augmented ; but, if I reverfe the procefs, and add a few drops
of alcohol to the water, the capillary column will fuffer a re-
markable depreflion. On this principle might be conftructed
a very fimple hydrometer for meafuring the ftrength of weak
liquors. And [ would invite chemitts to try capillary action
with different faline and metallic folutions, as I am confident
that many curious facts would thus be difcovered. Nothing
could exceed the fimplicity of fuch an inftrument. It is onl
neceffary to choofe a fine calibred tube, and to have it divided
on the outfide into equal parts by the point of a diamond, or
marked with enamel colours, On plunging it into the liquid
and then removing it, the precife effeét would be indicated
by the fufpended column. I have no doubt but that fuch
an infirument, in the hands of a fkilful operator, would be
brought to mark, with fufficient exa€tnefs, the proportion of
impredients contained in a compound fluid, and might in
fome cafes fuperfede the trouble of analyfis itfelf.

The afcent of water through pounded glals, fand, and
other powdery fubfiances, is juftly explained by capillary

yh action,

On Capillary Adion. 201

agtion. The effec is produced by the attraétion of the nu-
merous proximate facets ; and it is the more notable, as the
aggregate furface is very large in comparifon with the inter-
ftices to be filled up with humidity. But the abforption of
water by bibulous paper, linen, or flannel, though com-
monly referred to the fame caufe, is of a very different na-
ture. From clofe obfervation I am convinced that in thofe
inftances there occurs a real though not a permanent change
of conftitution: the folid begins to affimilate itfelf to the
qualities of the combined fluid, and becomes fofter and more
tranflucid. By means of an inftrument, contrived to mea-
fure the {malleft alteration of volume, I have proved deci-
fively that the union of water or oil with paper or linen is
accompanied with a general contraétion or concentration of
the mafs. Nay, applying a delicate thermometer, I perceived
a very fenfible extrication of heat invariably to take place
during fuch combinations. And this effect was the greater
in proportion to the previous drynefs of the folid. Thus I
have fometimes produced a heat of ten degrees by moiftening
faw-duft which had been parched before the fire. An ab-
forption of this kind is f{triétly a chemical procefs: the in-
ternal firu€ture of the folid is altered, and a force is deve~
loped very diftiné in quality and degree from what obtains
in capillary ation. The contemplation of fuch faéts ma
ferve to extend our ideas of chemical agency. The ftate of
fluidity is effential to its operation; but that quality is re-
quired only in one of the ingredients, and the refult of the
combination may be indifferently a fluid or a folid. Copper
will imbibe quickfilyer and become only more brittle; and,
on the other hand, quickfilver will diffolve a {mall portion of
copper without relinquifhing its fluid charaéter. Nay, if the
one f{pecies of combination can be produced, we may fafely
infer the exiftence of the other. Thus all ftones are found
to contain water incorporated in their fubftance, altogether
diftin& from what may infinuate itfelf in their accidental
crevices. If we reverfe the combination, therefore, and fup-
pofe the fluid to predominate, we fhall conclude that water
is to a certain degree capable of diflolving all forts of ftones.
And if, difregarding the authority of difputed fyftems, we
candidly examine the numerous facts that occur in geology,
we cannot hefitate to admit the juftnefs of the propofition.
I would not venture, however, to maintain that water is
fingly capable of diffolving the hardeft ftone; for the cohefion
of the integrant molecules will, in fome cafes, oppofe a force
fuperior to the attraction of the water. _ But the procels oe
e

202 On Capillary Ation.

be affifted by the concurrence of other agents that tend te
difwnite the folid. Jn general, the action of chemical affini-
ties admits of comparifon with the application of mechanical
force. There are fome obvious facts which at once illuftrate
and confirm this principle. For example, carbonic gas, com-
bined with water, enters into the compofition of marble; but
neither of thofe fugitive fubflances, however concealed or
difguifed, yet abandons its fpecific character. On the ap-
plication of intenfe heat their elaflicity becomes developed
with irrefiflible force, and they make their efcape, leavin
the ftony bafis in the dry cauftic flate of quicklime. — I thal
mention one other fact which exhibits the play of chemical
affnities.. Charcoal, it is well known, has the property of
imbibing air; and I have proved from experiment that this
imprifoned air exifts in a compretied or condenfed ftate. But
water, being applied to the charcoal, will be immediately
abforbed by fuperior attraction, and will diflodge the air,
which now recovers its ufual expanfion.

Sulphuric acid, potafh, and in general all the deliquefcent
falts, have the power of attracting moifture from the atmo-
fphere. - They exert areal chemical action which overcomes
the adhefion of humidity to the air. But I have remarked
the fame property to obtain more or lefs in a great-variety of
fubftances; in paper, linen, flannel, wood; nay, in ftones
and earths. The water, thus ab{tra¢ted from the atmofphere,
‘penetrates into their fubftance and difappears. The furface
of glafs fhows, in a limited degree, a fimilar power. I have
obferved that, on the approach of evening, bits of glafs be-
came covered over with minute globules long before the fur-
rounding air was abfolutely damp. About the temperature
of freezing I have noticed this dew to appear on the furface
of the glafs, when my hygrometer ftill indicated a drynefs of
five degrees. But in higher temperatures the effect was even
more {triking; and I have feen the fides of a tumbler covered
with dew when the ambient air poffeffed 15 degrees of dry-
nefs. In thofe cafes, however, the humidity is merely de-
tached from the air by the aétion of the glafs, and it remains
adhering to the furface without being abforbed into the vi-
treous mafs. The effect cannot, with any appearance of pro-
bability, be imputed to a fuppofed alkaline efflorefcence; for
it was oblerved with fine flint glafs, and the-dew collected
was always perfeétly taftelefs. When polifhed metals were
expofed, they never received any dew till the atmofphere was
abfolutely damp. They feem therefore to be entirely pafiive.

This fingular property of glafs is certainly a aici

ct)

On Capillary Aion. 203

of capillary action: it mufi therefore obtain in other kindred
fubfances. I am inclined to refer it to the fame caufe, how-
ever apparently fubtle, which has fo forcibly ftruck me in
fome other refearches. It is well underftood that phyfical is
different from mathematical, contaét. In the former there

is a finite interval whofe extent is various, depending on
the mutual relation of the bounding furfaces.. The degree
of approach is greater in fome cafes than in others, or
the contact is of a more perfect kind. I have proved
lately, I think to demonftration, that air is feparated from
the polifhed furface of metal by a much wider interval than
from glafs or other fubftances. The air therefore, charged
with its humidity, approaches fo clofe to the glafs, that the

_ latter exerts moft powerfully its fpecific attraction, and de-
taches the minute globules of water. Paper and other vege-
table fubftances, though faturated with moifture, and there-
fore capable only of difplaying capillary aétion, feem to pof-
fefs the fame property as glafs.

I confider the power of abftrating humidity from the at-
mofphere as of important confequence in the vegetable eco-
nomy. Plantsymay thus inhale liquid nutriment, when the
ambient air is ftill far from being difpofed to part with its
watery ftore. And we have feen that heat promotes the
effect. Hence certain vegetable tribes, without feeling the
beneficial influence of rain or dews, are yet capable of ex-
ifting in the fultry arid plains of Arabia. They extraét a
feanty fupply of moifture from the air by a fort of chemical
procefs. Perhaps the organic ftru€ture of the plant may con-
{pire with its phyfical quality in augmenting the effect,

The celerity of the flow of liquids in capillary fyphons de-
pends chiefly on a circumftance which, I believe,“ has not
hitherto been noticed. If we confider with a little degree of
attention the motion of water through a narrow paflage, we
fhall foon be convinced that it is not regular and uniform, The
obftruction at firft experienced occafions a certain accumula-
tion, which at length overpowers refiftance and caufes a par-
tial acceleration. In this manner, a fort of continual re-
ciprocating tide is produced in a feries of pulfes.more or lef{s
intricate. This curious effect is diftinGly vifible in artificial
jets-d’ eau, But the fame thing may be perceived in every
current of water. Hence the varying dimpled furface and
the gentle murmur, of brooks. The volume of water conti-
nues the fame; but its contours and flexures are inceflantly

_ changing, and toothe the fancy by exhibiting a picture of ani-
mation. After performing a certain cycle, however, the fame
irregularities are again repeated; and hence the aye ca-

cnce

£04 On Capillary Adlion.

_ dence of rivulets, fo clofely affociated in our minds with luxe
rious eafe and the calm pleafures of paftoral life.

If we examine carefully the afcent of mercury ina fine
thermometer, we fhall find that it mounts by a fucceflion of
ftarts. It feems to force itfelf along by a fort of vermicular
motion. Nor does the refiftance depend much on the fric-
tion experienced againft the fides of the tube; it is owing
chiefly to the wafte of force in impreffing a narrow thread of
liquid with thofe concatenated contractions and dilatations
indifpenfable to progreflive motion. I mutt obferve that the
term fluidity itfelf is merely of relative import. A folid body
may foften by infenfible gradations, and pafs into the ftate of
a fluid. In this new condition the particles are indifferent to
pofition, and therefore eafily admit of inteftine motion. But
fuch a property implies an extenfion of the fphere of mutual
connection. In a large fyftem of molecules, the flighteft al-
teration in the fituation of each is fufficient to produce a total
change of arrangement. It is otherwife when the group is
very limited. The compofition of a fluid may thus be con-
ceived to refembie a long fpring, which bends eafily and
without rifk under the fmalleft preffure; while the ftruure
of a folid may be compared to a fhort fpring, which yields
only to the application of a great force, and 1s then liable to
break. But the ation of heat extends this imaginary fpring,
and promotes foftnefs and fluidity. Thus a bit of fealing-
wax, held near the flame of a candle, gradually lofes its angles
and protuberances; an evident proof that the fphere of mu-
tual cohefion is enlarged. And every perfon muft have re-
marked that oil, during the beat of {ummer, becomes appa-
rently thin, and flows with facility. Nay, water itfelf under-
goes a fimilar change of conflitution, thongh it eludes ordi-
nary obfervation. I bend a thermometer tube, with rather
a wide bore, into a fiphon, which | infert into a tumbler of
cold water, and count how many drops fall ina minute. I
then empty the tumbler, and fill it to the fame height with
hot water; and, replacing the fiphon, | find that the drops,
which are ftill of the fame fize, fucceed each other much
more rapidly than before, infomuch as fometimes to form a
continual ftreamlet.. I conclude, from feveral trials, that the
velocity of the flow is at leaft fix times greater near the boil-
ing point than on the verge of congelation. But the dif-
ference may be rendered much more firiking in another
way. The height to which liquids are projected is pro-
portional to the fquare of their initial velocity. Provide, ,
therefore, a glafs tube three or four feet long and more
than half an inch wide: by the help of a blow-pipe, draw

5 out

On Capillary Action. 205

out the end into a tapering capillary bore, and, a little above
this, bend the fhoulder back parallel to the tube. Then,
holding the tube perpendicular, fill it with cold water, and
break off by degrees the flender ftem till the water begins
to fpirt up perhaps half an inch, Now plunge the lower
end of the tube, for the fpace of a minute or two, in boiling
water, and, on removing It, the jet will appear to dart almoft
to the height of three feet, but will gradually fubfide as the
heated portion of water is expended.

The {ame experiment will {ucceed, though in different pro-
portions, with alcohol and even mercury. Yet all thefe are
commonly deemed perfect fluids; nor can we doubt that the
application of heat will in every cafe increafe the tenuity of
the liquid fubftance, and. heighten its degree of fluidity. If
water thus experiences fuch a change, the effe& muft be pro-
portionally greater on the dilute folution of mucilaginous and
faccharine matter which conftitutes the fap of plants. The
return of fpring, by the mere phyfical influence of its warmth,
will promote the flow of the juices deftined for the nourifh-
ment of the vegetable tribes. That genial feafon, therefore,
not only reanimates the principle of life, and ftimulates the
organs of fecretion to elaborate their fluids, but quickens the
circulation of thofe fluids through the fine ramifications of
the fap-veffels. Hence the rapid growth of plants in the hot
climates. Hence, likewife, the quick vegetation remarked
within the polar circle, where, for the {pace of weeks or

~ months, the flanting rays of the fun play without intermiffion.
Verfailles,
Oftober 9, 1802."

* This paper was drawn up in great hafte for a particular occafion. It
is now printed without alteration, althongh the author is conf{cious of its
defegis in point of unity and arrangement.

XXXI. Ob-

[ 206 j

XXXI. Olfervations on the Salt of Bitumen; the Bit-Noben
of the Hindoos. By Joun HENDERSON, E/q. Surgeon
on the Bengal Eftabli/hment*. .

Sal Indus vel fubniger,vel fubrufus, obfcurus omnibus fortior.
Meffue, c. xvi.

Et alius eft Indus, qui eft niger, non nigredine napticitatis.
Avicenna, lib. ii, ©. 624.

i E faline fubftance which has lately been imported into
Britain under the name of /ali of bitumen, is not, as might
be inferred: from the title, a natural production, but an ar-
tificial preparation of great antiquity invented by the Hindis.
It is known in India by various appellations + ; but the trivial
name, by which it is familiar to thofe who have refided any
time in that country, is kala nimuc, or black falt. It is
met with in every village in large irregular lumps, for the
moft part of a dark brown colour.’

It has a ftrong faline tafte, with a peculiar fenfation dif-
fufed over the mouth, which is not eafily defcribed. At firft,
the tafte is difagreeable: but I have been told by thofe who
were in the habit of ufing it, that it not only becomes plea-
fant, but is often taken to remove a difagreeable tafte in the
mouth. When the falt is perfectly dry, it has fcarcely any
perceptible fmell, but when moiftened it fends forth a ftrong
julphureous foetor. f

It diffolves readily in a {mall portion of water, forming a
folution of a greenith colour, which emits a ftrong fulphu-
reous {mell, refembling bilge water, or the fouleft gun-feour-
ings. By expofure to the air, the fmell gradually abates,
and the greenith tint difappears, the liquor becoming as clear
as the pureft water: when this has taken place, if the folu-

* Communicated by the Author.—This prefents a curious fpecimen
of the Hindoo phyfic; and further, it may fuggeft to Britifh praétitioners
the trial of hydro-fulphurets alone or in combuftion, as in the cafe of the
prefent falt, im many untried difeafes.

+ By the Hindoos it is called dit-noben, padnoon, ands fooncher/oon; in
Arabic and Perfian MSS. melk, melk-nuft, melk-afwed, nimuct-nuft, nimu-
Gjfed, and nimuci-bindi, It is the fal-naphthicus Indus vel Indicus of the
Latin verfions of the Arabian and Perfian authors; the pharmacopeia au-
guftana of the earlier editions of the Pharmacopcia Londiuenfis, &c, It
rouft be obferved, that all the formula of which it is an ingredient in the
different pharmacopeias, are copied from the Arabian authors ; and there-
fore I doubt much whether it was ever imported into this country before,
or even into Europe in any confiderable quantity, for I find no particular
account of it in any of thefe books. It is, perhaps, the /al-q/phaltites and
fosomenus of Pliny and Galen,

tion

Odj/ervations on the Salt of Bitumen. 207

tion has been pretty ftrong, on pouring ont the water, the
infide of the veffel in which it was contained is found lined
with a cruft of a dark brown colour; a phenomenon obferved
in moft fulphur wells: this will be beft difcovered if the ex-
periment is made in a glafs veffel.

A filver fpoon laid over a freth folution of the falt became
difcoloured in the courfe of a few hours; and a little fugar of
lead put upon the fhank of the {poon, and kept over the fo-
lution during the night, was found in the morning confider-
ably blackened. A. few drops of the nitric acid added to the
freth folution caufed a milky appearance, and a little acetate
of lead poured into a glafs of it caufed a precipitate that filled
nearly one-third of the glafs. The hepatic gas 1s in fuch abun-
dance, that, by expofing a ftrong folution in a tumbler to the
air, the fulphur becomes at once evident, in the cruft with
which the glafs is uniformly found to be lined.

After a-fojution of the falt had been expofed to the air till
it became perfectly clear, a quantity of it was poured into a
china plate, and gradually evaporated by the heat of the fun:
there remained in the plate a number of cubical cryftals,
evidently pure common falt, without any other refiduum.
The falt, from the tafte, and fome curious phenomena at-
tending it, appeared to be of an uncommon degree of purity.

From thefe experiments it appears that falt of bitumen is

chiefly compofed of common {alt and hepatic air,-or, in the

language of médern chemiftry, of muriate of foda and ful-
phureous hydrogen gas, the two principal ingredients that
impregnate the mineral waters of Aix la Chapelle, Baden,
Harrowgate, Moffat, and moft of the celebrated fulphureous
fprings in Europe,

There are very few fulpburated {prings, either hot or cold, in
Hindooftan ; I only heard of one, ‘in the province of Burd-
wan,” in all the country from Hurdwar to Point Palmiras.
How far the Hindoos have fucceeded in difcovering the defide-
ratum for preparing them artificially appears from the above
analyfis, and will be confirmed by comparing a folution of
the falt with the fulphurated waters at their fources. All the
European procefles and machinery for imitating thefe waters
have been directed to the impregnation of water with gas dif-
engaged from hepar fulphuris, which produces an imitation
ef the fulphurated waters menvtioned by Dr. Coggan in his
Travels on the Rhine, but not of Moffat or Harrowgate : it
may perhaps be found that air difengaged from common falt
is different from that of bepar fulphuris, and in fulphur {prings
the falt feems to be a very univerfal ingredient. Not only
the waters already mentioned, but thofe of Corftorphine,

St,

208 Objervations on the Salt of Bitumen

St. Bernard’s Well; Broughton, Deddington, Crickle Spa;
Durham, Rippon, Shipton, Keddleftone, Sutton Bog, &c:
&c., have all common falt for their bafis. This difcovery
of the Hindoos is upwards of two thoufand years old, and
far furpafles all the attempts of modern chemifts to make
artificial fulphurated waters *: they have perhaps difcovered
the very procefs employed by nature in the formation of
them.

The Arabians and Perfians, and even the Muffulmans in
India, have generally confidered falt of bitumen a natural
production; and thofe who allow that it is made in the
country infift upon two kinds, the one natural and the other
artificial, and that the latter is only an imitation of the na-
tural. The Mahummedans have fuch a contemptible opi-
nion of the Hindoos, that they are much more difpefed to
believe it dug out of the earth, or formed from the water of
the Mare Mortuum, than that itis a prodution of Hindoo
chemiftry. Some of the chemifts to whom I fhowed it in
this country were alfo inclined to confider it as a natural pro-
duction. That it is an artificial preparation I am perfectly
convinced, from the information of the natives, from having
feen a mafs of the falt in the form of the earthen veffel in
which it had been made, and from having fucceeded, in a
great meafure, in making it: finally, Mr. Robertfon, the
gentleman who colleéted and fent it from India, writes, that
the falt is manufactured in the neighbourhood of the city of
Agra, where it may be had in any quantity. Although [
was at confiderable expenfe with the native chemifts and al-
chemifts, yet I muft confefs that I never prepared any falt
equal to what was to be got in the bazar or market-place.
I hall therefore not defcribe the different procefles performed
by my operators. I fhall only remark one part, in which
they all agreed, and that was, the igneous fufion of com~
mon falt with a very celebrated Hindoo medicine called
turp’bullat, or the three fruits, a name given by way of

%* Even in the gafeous part, the prefent artificial fulphurated waters are
faid to be different. Lu the report made to the National Inftitute of France
by citizens Fourcroy, Chaptal, &c. refpeéting the artificial mineral waters
of Mefirs. Paul and Co., they obferve, othly, finally, ‘* the fulphurated
appeared to the committee not fufficiently impregnated with fulphurated
hydrogen gas.”

4 Turp bulla is the atriful of the Arabians and Perfians, and the true
and genuine origin of thofe celebrated compofitions, long retained in the
pharmacopeias of Europe under the title of #yfbera; a word which feems
to have exhaufted the ingenuity of our lexicographers, who, I find, are
fat expelling it from their lexicons and diétionaries. It never had any
conneétion with the Greek word spupn, nor the “yphera of Scribonius

Largus. ag a
diftinétion

the Bit-Noben of the Hindoos. 209

diftinG@tion to the Chebul, Belleric and Emblic myrabolans.
I mutt here obferve, that there is not a particle ‘of fulphur,
alkali, or calcareous earth, ufed in the procefs. I have often
‘tried folutions of the ‘falt with infufions of flowers, thatiaf-
forded very delicate téfts ‘of the prefence of acids and alkalies,
‘but never difcovered)the fmalleft appearance of either.

As a medicine for man and beatt, falt of bitumen is more
extenfively ufed in Hindooftan than any article of the materia
thediea that I know of; and, except common culinary falt,
I know,no medicine the confumption of which comes near it.
It forms the bafis of thofe compofitions called mu ffalus, which
athe natives in charge of horfes, elephants, camels, and other
¢attle, are in the habit of demanding, once a month, or
oftener, as effentially neceflary to keep, them in, proper con-
dition. The Hindoos themfelves alfo ufe great quantities of

i, and-have frequent recourfe to it, to, improve, their, appetite
and digeftion. They confider it a fpecific for obitructions of
the liver and fpleen, particularly for that affection of the
fpleen called in England the a@gue, cake* ;,-which 1s, a very
frequent difeafe in India, and well known there by the sat
names peely and bofz.; Lt isa moft obftinate dilorder, ,often
continuing for years, and refifting the moft powerful reme-
tdies; after every other has failed, it has been frequently known
40 give way to a courfe of the ézt-noben. ud ;

It is in high eftimation as a remedy in paralytic diforders,
particularly for that fpecies of pally where the organs; of
fpeech are affected. It.is much ufed for different cutaneous
affections, worms, old rheumatifms, indigeftion, want of
appetite; in fhort, it is confidered the grand rettorative for
-man and beat in all chroni¢ diforders,.. Great quantities of
the falt are ufed by, the /editras, or native farriers; who feem

‘perfeétly to underftand the principle on which its efficacy
depends; for, after giving a horfe a dofe.of the falt, which is
done by mixing it with his food, they always give him water
to extricate the’ gas. Ye

* This affection is, I believe, a rare difeafe in England; and feldom
treated of in medical books. In the Eaft, it is not only often brought on
by long-continued fevers, but is a frequent primary difeafe, and under the
stitles wurm el tebal and amafi fepurz is particularly defcribed in almatt
PIEY Perfian and Arabic MS. on the practice of phyfic,

_ There is a remedy for the enlargement of the {pleen, now very popular
in Bengal, called Lynd's pill for the bfé, which, from the heterogeneous
“ingredients of which it is compofed, has generally been confidered by the
opeaétitioners there as an ufelefs tarrago: however, its efficacy has been
_fuch as to bring it into high repute. It was in analyfing this pill that L

came acquainted with the virtucs of falt of bitumen.
Mr. Lynd was a head furgeon of eminence on the Bengal eftablifhment,

boVou, XIV. No. 55. O XXXII. Me.

[ 210]

XXXIL. Memoir on the Refining of Lead 5, with fome Reflec-
» tions on the Inconvenience of Afb Cupells; and the Defcrip-
tion of a new and economical Method of conjtruéting Cupetts
<cor Refining Veffels: read in the French National Inflitute.

By C.Duvamen, Member of the Inflitute and, Infpeétor
of Mines*, ay:

Ir is well known, that to feparate filver from lead, a’metal+
Turgic procefs called refining or cupellation, performed in a
Veffel called a cupell, has been employed: it is known alfo
‘that this veffel is compofed either of the athes of the bones
‘of animals, or of thofe of vegetables, after they have been
lixiviated, to free them from the faline matters whith they
‘May contain. sort
The great quantity of wood-afhes which muft be em loved
in the conltruétion of cupells, and the difficulty of obtaining
‘them, long ago induced me to endeavour to difcover a fim-
‘pler and lefs expenfive method of conftruéting the veffels in
queftion, The old chemifts having obferved that lead be-
‘comes oxidated, or reduced into what is called Jitharge, when
expofed to heat, or the contaét of the atmofpheric air, while
‘the filver united to it retains its metallic form, nothing feemed
neceflary but to find the means of feparating thefe two me-
tals. They were conducted .to the method of accomplifhing
‘this by obferving that the oxide of lead, in its ftate of liquefac-
‘tion, eafily penetrates the fubflances which are in contact with
it, and elpecially bone-afhes, without deforming the veffels
“which are formed of them. No matter, indeed, ‘is more
sroper than the latter for conftrudting {mall refining cupells.
The difficulty, and often even the tmpoffibility, of obtain-
ae about 160 Englifh gallons of afhes for each operation of
tefining on a large feale in the German furnaces, made the
“proprietors have. recourfe to: wood-athes ; but, befides ‘that
thefe afhes are expenfive, it often happens that they cannot
be procured in futicient quantity. They are even attended
«with one inconvenience, which is, that they come off, and
‘float on the fufed lead; the refining then fails: and this
‘takes place every time that the afhes are badly prepared, that
the cupell is ‘infufficiently or not uniformly beat, or when
-the canals deftined for. the evaporation of the moifture are
neither in fufficient number, nor properly arranged, nor co-
‘yered with a ftratum of fcoria, on which is eftablifhed the
bottom, that-receives the afhes, and which ought to be eon-

® From the Journal des Mivies,, No. 64.

: . firucted

Memeir on the Refining of Lead, Sec. QIT

ftrugted of the moft porous bricks, in order that the water,
with which it is neceffary to moiften the afhes, may pene-
trate them in evaporating, may proceed to the bed of fcoriz,
and efcape by the fpiracles which are at’the bafe of the fur-
nace. |

To afcertain the proportion of lead in filver, it is fufficient
to put fome pennyweights into a {mall cupell of bone-athes
placed under the muitle of an affaying furnace. In propor-
tion as the lead becomes oxidated, it infinuates itfelf into the
cupell, and the filver at laft affumes that vivid appearance
which announces that the whole lead is diffipated, that the
filver it contained is refined, and has attained to its maximum
of purity.

In refining on a large feale, the objec alfo is to feparate
the filver from the lead, but not to make the whole of the
latter penetrate into the cupell, which is even impoffible ;
for in that cafe it would be neceffary to have a much larger
quantity of afhes for the total abforption of the metal: be-
fides, the operation would require a period ten times as long
as that ufed in general for refining, and would occafion ten
times the expenfe in fuel, and a much greater lofs of the
metals than by the ufual procefs, where the ‘greater part
of the Jead is obtained in litharge, while a portion pene-
trates into the cupell for about two inches of its thicknefs,
which muft be fufed to revive the lead. This reduétion is
alfo more expenfive, and experiences a greater lofs than the
ditharge, which is eafily fufed, and which, without paffing
through the furnace, may be employed as an article in com-
merce.

Lead ore and litharge may be fufed as in England, and
the department of the ci-devant Brittany, in a reverberating
furnace the foles or bafons of which are formed of pounded
and moifiened clay. Thefe foles can ftand the action of
heat and of the oxide of lead for fix or eight months of un-
interrupted labour.

The durability of thefe earthen foles gave me the firft idea
of the method, which I fhall hereafter propofe, for refining-
furnaces, where the only thing required is to oxidate the
Jead to obtain it in litharge, aid not to caufe the cupells to
imbibe the whole of it, as is done when the objeét is to aflay

_the-metal in order to know whether it contains filver. In

‘operating on a large fcale, the cupell, though of afhes, ab-
forbs only a part of the lead, as | have already faid, obferv-
ing at the fame time that it would be much more advan-
lee to obtain the whole transformed into litharge, the

uétion of which into lead is much eafier than that of the

: O02 oxide '

21% Memoir on the Refining of Lead;

oxide contained in the afhes, which oppofe fufion, and the
feorie of which always carry with them fome of the metal.

In acupell of afhes beat into am oval circle of iron, the
pos diameter of which is only five or fix feet and the

efs one yard, the Enghfh refine from a ton to 23 cwt. 0
lead, which is converted into beautiful litharge, except the
{mall portion which penetrates into the cupell, the thicknefs
of which is only about 23 inches, and which is fupported
under the arch of the furnace by two bars of iron. A pair
of leather belfows drive the litharge towards the anterior part
of the furnace, from which it falls, without interruption, on
the floor of the foundry, while, to fill up the vacuity left by,
the oxide running off, an ingot of lead placed clofe to the
bafe of the bellows is made to advance gradually into the ins
terior part of the furnace. This Jead, by fufing, keeps the
cupell full till towards the end of the operation. i

If I have here given a fhort view of the. procefs of the
Englifh, it is only to fhow that it is poffible to perform ope-
tations of refining by employing only a fmall quantity of
afhes for the conftruétion of cupells. Thofe in queftion do
not abforb go pounds of oxide in the large quantity of lead
which is refined.

It is then proved that metallurgifts have always endea-
voured to obtain the greateft quantity poffible of litharge,
and little afhes impregnated with oxide; but as they thought
that they ought not to deviate from the docimaftic procefs,
they have always conftruéted their cupells of athes. ;

It has been feen that in cupellation on a {mall feale, lead,
in proportion to its oxidation, penetrates the afhes. When no
more is left, the fmall button of filver remains pure at the
bottom of the bafon under a fpherical form. This operation
takes place with the more celerity, as the furface of the mafs
is always conyex in thefe {mall veflels; which allows the oxide
to flow as on am inclined plane, towards the edges of the
eyipell, where it is immediately imbibed.

~The cafe is not the fame with cupells on a large feale,
which are feveral yards in diameter: bellows muft be ap-
plied, the wind of which ferves not only for accelerating the
oxidation, but alfo for driving the litharge towards the gutter
formed for its efcape.

We have remarked the inconveniences and even the im-
poffibility of making the whole lead penetrate into the afhes
of large cupells: oxidation, indeed, isnot effected but in the
parts of the mafs expofed to the contact of the air or to the
wind of the bellows; but as litharge, towards the middle af
the bafon, could not reach its edges, it would remain there

: in

and the Inconvenience of Afb Cupells. 213

in a ftate of ftagnation, and would neceffarily oppofe the
formation of a new ftratum of oxide. This has induced me-
tallurgifts to expel the litharge by the wind of a pair of bel-
lows in proportion as it is formed, and to make it flow from
the furnace.

Oxidation then takes place only at the furface of the mafs,
and not at its lower part: if the cafe were otherwife, the
aflies of cupells would be penetrated by the oxide to a thick-
nefs the more unequal, as the operation is longer ; but I have
always remarked, that the te, or the part of the afhes im-
pregnated with litharge, in refining on a large feale, is not
‘thicker in the centre of the bafon than towards its circum-
ference, though the lead remains thirty or forty times as long
in the bottom as on the edges; fince the mafs continually
decreafes till the whole lead is reduced to litharge, and till
nothing remains but a cake of filver at the bottom of the
cupell.

If the whole lead is imbibed by the affaying cupell, it 1s
Hecaufe this fmail veffel is expofed to a heat uniform in all
its parts. As the cupell, in operations on a large {eale, pre-
fents to the action of the caloric only its upper furface, the
oxide imbibed ceafes to penetrate it at the place where the
temperature is no longer bigh enough to keep that oxide in
a fate of fufion. For this reafon, the thicknefs impregnated
is equal throughout the whole extent of the cupell ; and this
prevents the poflibility of making the whole lead penetrate
into the afbes.

From the above obfervations it may eafily be conceived,
that if the affaying of lead ought to be performed in fmall
“cupells of bone-afhes, in order that the oxidated metal may
penetrate them, and be in part evaporated, the cafe is dif-
‘ferent with refining on a large feale, where it is neceflary to
‘accelerate the operation, and to obtain as much litharge as
? poffible.

i ~~ T have already faid, that the wood-athes of which cupells
‘are made for refining on a large feale are expenfive; that
very often a fufficient quantity cannot be procured ; and that
“befides this, part of the afhes, and fometimes the whole, fe-
‘parate themfelves entirely from the fole ; which occafion a
‘confiderable lofs. I thall’ add, that to give more weight and
‘eonfiftence to the cupells, it is often neceflary to mix with
‘the athes a Jarge quantity of fand ; efpecially if the lead con-
“tas foreign f

_

n fubliances, fuch as arfenic, cobalt, antimony,

‘tin, &e. If the lead be only arfenical, after having feparated
the firftfeum, a quarter of a hundred weight of iron filings or
-calt iron turnings are now and then thrown over the whole
03 furlace

214 Memoir on the Refining of Lead;

furface of the mafs. This iron, being lighter than lead, floats
over it and abforbs the arfenic, after which the mafs mut
be feummed ; foon after, the litharge is formed without any
obftacle. This method is employed in Saxony.

_ The neceffity of adding fand to the afhes of cupells muft
have conducted to the difcovery of the following means, which
I fhall here propofe.

New Method of conjiruéting Bafons for Refining.

Without making any change in the mafon-work of the
refining furnace, called the German, care only muft be taken
to form at the bottom a fufficient number of canals for the
evaporation of the moifture, and to arrange them in the
manner betft calculated to produce that effect. Thefe canals
or fpiracles mult be covered with a bed of fcoriz, over which
a pavement is to be made of one layer of the moft porous
bricks.

On this area, which muft be concave like the fole on which
the afhes of, common cupells are beat, place founders’ fand
a little moiftened; to which may be added a fifteenth part
of argil, if it is not fufficiently eartby, in order to give it the
requifite folidity ; and the whole muft be carefully mixed.
This fand muft be rammed in the fame manner as for con-
folidating afhes; and a refining bafon is to be formed in like
manner, uniformly beat in all its parts, The thicknefs of
this cupell muft be fix or feven inches: it may be formed of
two ftrata, as will be feen hereafter.

After the bafon has been uniformly beat in every part,
about a gallon of lixiviated wood-afhes may be fifted over its
whole furface, and rendered adherent with beaters.

When the cupell is thus prepared, let down the head on
the furnace and make a moderate fire in the fire-hole; which
muft be maintained for feveral hours, in order to caufe a part
of the water, with which the fand has been moifiened, to
evaporate. The furplus will be diffipated during the opera-
tion, without any inconvenience, by canals of evaporation.

After a fufficient deficcation, raife the head and fuffer the
cupell to cool a little; fpread out ftraw or hay over it, and
arrange the ingots of lead, placing them gently on it that
their weight may not derange the fand: jt is to prevent fuch
derangement that flraw is employed, as is done in regard to
cupells of bone-afhes*. When the quantity of lead necef-
fary for filling the cupell is arranged in the furnace, let down

* Inftead of prifmatic ingots it will be better to caft the lead in hemi-

fpherical iroa moulds. Pieces of that form are lef liable to damage the
eupell, : re Se ty

- the

and the Inconvenience of Afb Cupells. arg

the head, and, having luted it round with foft clay, make
fire in the fire-hole as for the common operations of refining,

When the lead is in complete fufion, and the mafs is
Covered with feum and charred ftraw, make the fcum or
drofs run off by the gutter for the litharge with a bit of
board about a foot in length, in the middle of which is faft-
ened a rod of iron of fuflicient length to traverfe the furnace
and about a yard more.

When the lead has been well feummed feveral times, and
begins to be red, make the bellows aét, but at firft gently ;
arrange the nozzles of them in fuch a manner, that the wind
iffuing from both may be direéted to the centre of the cu-
pell; and in order that the wind may be always reverberated
on the mafs, adapt to the extremity of each nozzle a fmall
round piece of iron plate. This kind of valves, which the
French refiners call papillons, is employed for refinin
according to the German method. They are fufpende by
hinges at their upper part: at each ftroke of the bellow: the
are half raifed, and they reverberate the wind on the lead,
which accelerates its oxidation. :

After all the drofs or feum is removed, and when the lead
has become exceedingly red, and covered with a ftratum of
litharge, form, with a fmall iron hook deftined for that pur-
pofe, a fmall gutter in the fand of the cupell, which mult be
dug deeper, gradually and with caution, until the bottom of
it bé on a level with the mafs. The Jitharge then, driven by
the wind of the bellows towards the anterior part of the fur-
nace, will run by this gutter and fall on the floor of the foun-
dry, as is the cafe in the common operations of refining.

When the refiner obferves that no more litharge remains
in the neighbourhood of the gutter, he will ftop the flowing
off with a fmall quantity of moiftened afhes:. but as foon as
the lead again becomes covered with oxide, the gutter muft
be opened, and muft be dug in proportion to the diminution
of | mafs, taking care that no lead efcapes, and particu-
larly towards the end of the operation; for it would carry
with it a great deal of filver, which would be loft. You mutt
proceed in this manner till the filver has acquired its vivid
colour; taking care to increafe the fire in proportion to the
diminution of the mafs; efpecially when the operation is
nearly terminated, becaufe the filver then is collected toge- *
ther: and, as it is much more difficult to be kept in fation
than the {mall quantity of lead which remains united with it,
it could be refined only in an imperfect manner at an infuf-
ficient temperature; and inftead of about a twentieth of lead,
which the filver generally contains in the German refining-

houfes,

215 Memoir on the Rejining of Lead ;,

houfes, it) would remain charged with a great. deal more,
which would render it more difficult to proceed to a fecond
operation, called the refining of filver, by which it is carried
to the required degree of purity. The Germans call this fe-
cond procefs /ilber brennen, burning filver,

Thofe accuftomed to the refining of lead according to the
German method, will be able to perform that which I here
propofe ; for, though the cupell be of fand inftead of afhes,
the operation muft be eonduéted in the fame manner.

It has been feen that the Englifh refine a large quantity of
lead in a fall cupell: in the like manner, a great deal of
metal may be made to pafs by that which I propofe, if care
be taken to add more metal] as that which is oxidated efcapes,
If we fuppofe that the cupell is capable of containing four or
five tons of lead, above fixteen may be refined at one opera-
tion; which will not be attended with the inconveniences of
the Englith procefs, :

I have reafon to think that a cupell of fand well con-
ftruéted may ferve for feveral operations without the neceffity
of re-conftruéting it each time, as is the cafe with thofe of
afhes; but in this cafe, and before the lead is introduced,
hee muft fill up the gutter which has been made for the
itharge to run off, after having removed with a chifel the
kind of varnifh which the oxide of lead has left on the fides
of it, in order that the new fand, fomewhat moiftened, may
form an intimate conneétion with the old fand, which muft
alfo be watered in that part before the new fand is depofited.

The long duration of earthen foles in reverberating fur-
naces, where lead ore and even litharge are fufed, as I haye
already mentioned, leaves no room for apprehenfion in regard
to the action of the oxide of lead, which will a& only at the
furface of the cupell, and will penetrate only a very fmall
part of its thicknefs.

After one or more operations of refining, this cruft muft
be removed, and fufed in a furnace in contact with fuel, in
order to obtain the Jead. This procefs will be as eafy @s the
reduction of that metal contained in the afhes of common
cupells, and in a much fmaller quantity.. More litharge then
will be obtained by the new method than the old; which is
an advantage, as I have already obferved. I fhall here add, that
as the fole of fand does not abforb fo much oxide of lead as
that of afhes, it will not carry with it fo much filver; for it
is well known that lead revived from its afhes always con-
tains more than that which arifes from the reduction of
litharge. !

Intiead of fand, argillaceous earth might be employed for

the

and the Inconvenience of Afb Cupells. 217

the-conftruction of cupells,.as is the cafe in regard to the
Toles of the reverberating furnaces in the ci-devant Brittany;
but it would be neceffary to ram this earth repeatedly for fe-
veral days; otherwife it would fplit, and thefe cracks would
increafe by the fhrinking which muft refult from the heat,
and Jead would infinuate itfelf into thefe fiffures: an incon-
venience which cannot take place with fand even a little
earthy. I fhall obferve alfo, that a fole of earth would har-
den too much to allow a gutter to be dug for the paflage of
the litharge: in this cafe it would be neceflary that the place
deftined tor the oxide to run off fhould be conftru€ted with
fand or lixiviated afhes.

I fhall,add alfo, that it will be advantageous to employ two
kinds of fand in the formation of the bafon of the cupell ;
one kind. fine like that ufed by founders, and the other coarfer
and not earthy: the latter will form the firft ftratum, which,
after being beat with rammers deftined for that purpofe, ought
to be about three inches and a half in thicknefs. The fine
Yand, a littlé earthy, muft then be applied over this firft ftratum
to form a fecond, which is to be rammed like the former. Both
thefe kinds of fand muft be fomewhat moiftened before they
are introduced into the furnace, in order that they may be
better heaped up, and be confolidated by the rammers.
~ The fand-of the lower ftratum, being coarfer than that of
the upper, will abforb the moifture of the Jatter in proportion
as it evaporates ; and it will pafs without any obftacle through
the canals cifpofed for that purpofe.

The lower ftratum of fand may remain in its place when
‘a new cupell is to be ‘conftructed with fine fand, and the part
of the latter, which has not been impregnated with oxide,
smuft be mixed with new fand to form a cupell. ~ Care muft
be taken in raifing this fand not to touch the lower {tratum ;
for the fand of the latter, which is coarfe, muft not be mixed
with the other. This inconvenience may be avoided by
-beating over the bed of coarfe fand a thin ftratum of afhes, °
at which you mutt ftop in removing the fine fand of the upper
ftratum.

‘It bas been faid that the founders’ fand muft be fome-
what earthy, and that, if it is not, a litde argil muft be added
to give it cohefion: but, as it is neceflary that this argil
Should be uniformly diffufed through all the parts of the fand, _
it muft be diluted in the water with which the fand.is moift-
ened, and the whole matt be carefully mixed.

It may be objected, that as cupells of fand do not abforb
fo much litharge as thofe of afhes, more time will be required
to terminate the operation of refining ; fince, in the new wa

cefs,

218 | On Painting. |
cefs, the oxide, inftead of being abforbed, ought to flow from
the furnace. This circumftance needs excite no uneafinels ;
for the wind of the bellows, if well dire&ted, will make the
litharge flow along the gutter more abundantly than if there
had been an abforption. é

I have feen refiners in Germany, who, in conftruéting their
cupells of afhes, formed in thesmiddle of it a fmall circular -
deprefiion the diameter of which was proportioned to the
quantity of the filver which they knew to be contained in
the lead fubjected to the operation. By this excellent dif-
pofition no grains of that valuable metal remain infulated
from the cake; the whole runs into the central bafon, and
forms a cake perfectly round. JI would recommiend this
practice. -

I am certain that the cupells here propofed, if carefully
and properly conftruéted, will be attended with complete
fuccefs;. will be free from the inconveniences of thofe of
afhes, and at the fame time will be economical. Tam de-
firous, for the benefit of metallurgy, that the method here
pointed out may be put in practice: it will prove that we
ought not to be too tenacious in adhering fervilely to antient
ufages or to the common routine of workmen.

XXXIIL On Painting. By Mr. E. Dares, Painter*.

] THINK it right again to repeat, that I have not obferved
any-order in the production of thefe Effays. They were
written as the fubjeéts arofe in my mind, and the pre-
fent paper fhould be confidered rather as an introduétory
addrefs than otherwife. My motive in writing the prefent
eflay was to endeavour to remove the prejudice of thofe who
confider the arts as a ufelefs ftudy, and their produce as
things merely ornamental. But who, in a ftate of civil fo-
ciety, would be content with the ufeful or neceffary? Who
is he whofe foul feeks not after perfection ?

The motions 6f his fpirit are dull as night,

And his affections dark as Erebus:

Let no fuch man be trutted.

The fubje& of the following effay had long engaged my
attention; but I had dropped the idea of writing on it, in
confequence of fome intelligent friends obferving it would
‘be ufelefs, as no one could be fo ftupid as not to fee the ufe-
fulnefs and influence of the arts on fociety. Experience,

* Communicated by the Author.
however,

On Painting. 219

however, has taught the contrary; and I have been further
ftrengthened in my refolytion by obferving, that the French
National Inftitute, in their public fitting of April 5, had
thought the inquiry of fufficient importance to offer it as a
fubject for the premium of a gold medal *. .

Francis-fireet, Bedtord-fquare, EDWARD DavEs.
November 30, 1502.

Essay VIL.
On the Power and Ujefulne/s of Drawing.

Tam perfuaded that to be a virtuofo (lo far as betits a eentieman) isa
higher fiep towards becoming a man of virtue and good fenie, than the
being what in this age we eall a tcholar. Lord Shafiefoury.

IN this eday we have two objects in view: to fhow the
connection of drawing with painting ; and to exhibit, in as
clear a manner as we poflibly can, its ufefulnefs and influence
on fociety. .

But before we proceed it may be neceflary to obferve, that
thofe who would queftion the utility of the arts, would be
equally difpofed to queftion the utility of thele eflays that treat
about them. Of their ufefulnefs we hope to be able to offer
numberlefs proofs; but they rife fuperior to the merely ufe-
ful. For that which is neceflary is neither ornanrented nor
elegant, becaufe neceffity implies poverty, while ornament
implies abundance. Hence architecture, as an art, does not
apply to mere houfe-building.

In defence of thefe eflays, they are ferviceable by exhibit-
ing the ufefulnefs of truth ; and fo far they become an objeé&t
to all thofe who with to be acquainted with the fubject han-
dled, and to obtain a knowledge therein. But to.thofe who
never tlrink or inquire, or concern themfelves with matters
of fpeculation, or who take up with {peculations without ex-
amining them, or read only to confirm themfelves in fuch as
they have received, not any thing can become an object of
concern, or any book be ufeful. .

That man was not intended by nature for purpofes bale
and ignoble, none will deny ; and, if arguments were wanted,
they might be drawn from that eternal inquiry after what-
ever is grand, dignified, or exalted ; and, finally, after a fiate
fuperior to our prefent terreirial one, For it is not too much

© We cannot help thinking that Mr. Dayes has judged well in taking
dp this part of the i bjed. Jr is of great importance, and he has rendered
an effential fervice not only to the art itfelf, bur to its liberal profcflors, by
removing, as his arguments effectually do, ill-grounded prejudices, againgt
its indifpenfable utility in civilized fociety ; prejudices which could only
originate in, and be fottered by; ignorance and fupidity —EDiToR.

to

220 On. Painting,

to affert, that we approach the Divinity in nothing fo much ©
as in wifdom. Hence, as the arts are conneéted with wif-
dom, as men become carelefs of their culture, they become
equally incapable of fulfilling the duties of focial beings. For
knowledge is what humanizes mankind; reafon inclines
them to mildnefs, but ignorance generates prejudice, which
eradicates every tender feeling. ‘

By drawing is meant the exact imitation of all the forms
and manners which prefent themfelves to our fight; and in
knowing how to give every thing its proper and correfpond-
ing character agreeably to the fubje&t confifts the excellence
of what the artift terms @ good draftsman.

Drawing, as far as it is conneéted yvith mere imitation, is
a mechanical operation, and may be acquired by a perfon of
very moderate talents. So may a*knowledge of bodies, pro-
perties, facts, events, and fables, by reading. But the powers
of invention, the v7s poetica, which diftinguifhes the bard
from the mere verfifier or journalift, the genius from the
Mere imitator and copyilt, muft be a gift from heaven be-
ftowed at the formation of the being. Neither this poetie
energy nor the inventive powers of the artift can be taught
in fchools or academies ; but they both may be buried in ruft
and inaétion, if proper objeéts are not prefented to call them
‘Into motion. So the inventive powers of genius will be fue
tile if unaccompanied by a fkill in drawing. Without this,
the learning of the painter or feulptor cannot be fhown to
advantage: it is the /ime gua non by which all the other ac-
complifhments are difplayed. '

From what has been already ftated, the dependence of
painting on drawing muft be obvious.

Genius has been compared to fire from flint, which can
only be produced by collifion : if fo, fuccefs mutt follow where
nature direéts and perfeverance attends. Activity is a ne-
eeffary ingredient to enable us to obtain a knowledge in art ;
and fhould we find others out-f{tep us, let us redouble our
diligence, and’ comfort ourfelves with the recollection, that
2 late fpring produces the greateft plenty.

No one can poflibly judge of his powers from mere fpeeu-
lation ; the teft mutt be applied before the value of the gold
can be known. Nor will inaétivity ever difeover how far
our fortitude will enable us to overcome difficulties, our pa-
tience to bear difappointment, or our induftry enable ,us
to range the wide field of art. For, were the arts of eafy at-
tainment, they would be unworthy the notice of a great
mind. This fhould induce us to increafe our exertions in
proportion to our difappointments, remembering that to te

with

On Painting. a2t

with difficulties is noble, but to conquer is one of the higheft
points of human felicity. It isin Mah as in writing
where difficulties oocur, they arife from not clearly under-
ftanding the fubje&t. Hence, to be able to reprefent an ob-
ject juitly we muft underftand its fabrication; for it would
be in vain to think of drawing the arch of a bridge correctly
without knowing how it was keyed or put together, or even
a bafket if we did not know how it was wove.

We fhall now proceed to confider the power of drawing
in a point of view merely ufeful.

How limited muft their ideas be who confider it as * the
foundation of painting” only! We know it is fuch : for with-
out drawing it would be in vain to think of producing an
effe&t; as mere colour without form muft remain a crude
and undiltinguifhable mafs.

Drawing is not only an accomplifhment the moft elegant,
agreeable, and ornamental, but, at the fame time that it is
the foundation of painting, is of the utmoft utility to the
feulptor, the civil and naval archite&t, the engraver, the
engineer, the mathematician, and navigator. It alfo affifts
the gardener, the cabinet-maker,; the weaver, &c. In fhort,
there is fcarcely a branch of civil fociety that is not indebted
to it, from the maker of the iron rails before our houfe to
the tea-urn on our table. To it we are indebted for repre-
fentations of thofe elegant remains of antiquity that have
contributed fo much to the advancement of our knowledge of
fine form. Volumes of verbal defcription will never convey
fo true an idea of a thing as the moft flight fketch. Hence
the fource of much of our knowledge in antiquity, of which
language could convey no adequate idea.

To be able on the fpot to make a {ketch ofa fine building,
beautiful profpeét, or any curious produétion of nature or of
art, is not only a very defirable and elegant accomplifhment,
but in the higheft degree entertaining. To treafure up what-
ever ‘may occur in our travels, either for future ufe or to illuf-
trate converfation, to reprefent the deeds of the great of for-
mer ages, to preferve the features of ‘our moft valued friends,
has made this art not only one of the highe(t embellifhments
of our nature, but the delight of all ages. The greateft wri-
ters have united to praife, and empires to encourage it. It
has been in the bigheft degree morally ufeful; and, where it
has flourifhed, conferred honour on the country. In fact,
fociety could not fuftain a more fevere lofs than in being de-
prived of it; as many comforts, and all thofe elegancies that
adorn the prefent ftate of our being, muft depart with 5 :

* at

222 On Painting.

_ What has been the fate of thofe people whofe lawgivers
forbid the practice of one part of the elegant arts? It appears
they well knew, that where art refides, wifdom will ever be
of the party; and dreaded the downfall of opinions built on
a falfe bafe. .

. Wifdom is power, and power is what preferves a nation ¢
hence thofe who fhut the door againft knowledge are wilfully
‘ feeking their own deftruction: fuch is precifely the prefent
fate of the Turkith empire.

Ye gods !. what juftice rules the ball!

Freedom and arts together fall:

Fools grant whate’er ambition craves ;

And men once ignorant are flaves. Pore.

- What was the fate of Crete, that was fo renowned for her
wifdom, valour, and laws? How did fhe fink under the
tyranny and oppreffion of Rome? With their freedom de-
parted their arts, their fciences, their valour, and their virs
tues. With the lofs of liberty we lofe all the ardour nature
bas furnifhed us with to ftrengthen and fupport the flame of
genius and the ardent glow of yalour: without it we become
deftitute of. vigorous refolution, and fink below the natural
virtue and dignity of our fpecies.

Drawing may be faid to poffefs a divine virtue in its crea«
tive power, «and to be a perpetual miracle, as it preferves the
images of diftant objects, and the likenefs of thofe we love.

Without rifking our lives on the boifterous ocean, we may
enjoy at home, in a {mall book, reprefentations of ‘the fineft
productions of nature and art fituated in the remoteft regions
of the world.

The wealth of a ftate, and the degree of civilization of its
inhabitants, are {hown in the perfection of the elegant arts :
no country ever flourifhed without them.

To {peak of the power of drawing in a very limited point
of yiew: without it we could not have maps and charts;
without them we could not navigate; and without navigation
we could not poffefs the advantages of commerce. Its appli-
eation to fhip-building muft be obvious, as every part is
made to afcale. ‘As a mere power of imitation, it unquef-
tionably fets man at the head of creation, no other animal
having made even the attempt.

The arts have not only an influence on our manners but

affions, and, taken in a national point of view, are highly
ufeful. The pidtures reprefenting gallant actions or noble
achievements ronfe and flimulate to atts of heroifm and

public

——_-- - _:

= era

On Painting. 225,

public fpirit ;. while thofe of a more elegant turn exhibit ex-
amples of graceful addrefs, and incline the mind to aéts of
beneficence and virtue.

However much we may lament that hiftorical painting is
not fyfficiently encouraged, yet we muit diffent from thofe
who fupport the old but erroneous opinion, that our love of
portrait-painting arifes from a national vanity, This ridi-
culous idea tog bandied about, both by foreigner and
native, till many who take up with opinions without exa-
mining them have believed it true. We boldly affert, on
the contrary, that it is national virtue that gives it birth, and
a defire the moft rational, that of preferving the images of
‘thofe we love and delight in, conitantly before our eyes. It
argues great national beneficence and goodnefs of heart. We
may in fome meafure judge of the difpofition of the mafter.
of a houfe from the number of portraits he poffefles: they
cannot be likeneffes of his enemies. Hence his choice muft
be founded on love, and not, as the antients’ was, on pride
and vanity. The portrait-painter therefore becomes morally
ufeful by increafing that focial tie that binds fociety together,
in keeping before our eyes the images of departed worth or
exifting merit. It is only thofe who neither love nor are
beloved, that have no need of the portrait-painter.

Among the number of our own national advantages, and
which fome may think fuperior to all others, we may obferve

~ that the excellence of our artifts has turned the balance of

trade in our favour. For whereas we formerly imported vaft
quantities of prints, we now fupply all Europe, and import
very few. Even for the ‘decoration of our books we were
formerly obliged to apply to ftrangers: but Heath has added
a tafte to that department of art unknown to former engravers

in the hiftorical line. Among the topographical] publications,

thofe prints that accompany the ‘‘ Beauties of England and
Wales” mutt be highly interefting for tafie and beauty.

In the beginning of the laft century, the writers on the
continent amufed themfelves in endeavouring to aflign a
caufe for the dulnefs of us iflanders in not having produced
one hiftorical painter. Our northern latitude, being involved
in fogs, was among the reafons affigned: but the caule of
fuch abfurd inquiries has ceafed, and the mental capacity of
Britons no one will now dare to queftion.

The confequence of our nation and the arts appear to have
advanced together. The firft is evinced in our colonjal pof-
feffions ; and if we go back to the time of Henry VIII,, we .
hall eafily difcover the ftate of commerce and the comfort-
Jefs fituation of fociety compared with the prefent, sell

€

924 On Paintin.
fhed obferves”that chimnevs were a novelty, ‘as’ were pewter”
ornaments for the table. Straw formed the bed, and a’ good
hard block of wood the pillow. _ Then was the dawn of the
arts, Since which time they have’ been advancing, and are
now, thank God! matured’into’ 2 glorious midday, unde
the aufpices of his ‘prefent majeft¥2? iS sq que

It is impoffible to fpeak of thé arts without'exprefiing our
gratitude towards their great patron; and were his name’ to
flourifh in no other way, that of George IIT. will be:facred
to pofterity with thofe of Leo, Julins, and all fuch as havea
claim on eternity, as their protectors.. His majefty has done
for the arts what no monarch of this nation ever did before +
he has given, by his patronage, a turn to the national tafte
highly beneficial to the profeffion, which the public are bound
to fupport by a hberal and fair encouragement. With ‘refpe&t
to the mere aét of buying, we are bound to confider his ma-
jefty in the light of a private gentleman, who regulates his
expenditure according to his income :’ and we ought to'thank
God it is fo. : 2th

Holbein had not tafte enough to change the grotefque fa+
fhions of the court of Henry VIIT. Hé brought about a re+
volution in architeéture; but he introduced a mungrel ftyle,
inferior to the Gothic of that period. Zuccaro: was it
England in the time of Elizabeth; and during that long
reign we find little improvement in architeéture, drefs, of
in the general circle of eleganciés. It was a court of in+
trigue and vanity. In the reign of James I. Van Somer and
Cornelius Janfon paved the way for Van Dyck-—an epoch
of tafte: but this appears to have been confined to the court
and a few noble coNeétors; and the troubles of Charles his
fucceflor prevented his giving them a more genera] influence.
His reign ftands high*in the hiftory of architeéture, from hav-
ing produced Inigo Jones. Under Lely tafte funk into Indiary
gowns and flowing perukes; till fafhion became a montter in
the time of Kneller, and appeared in buckram coats, fquare-
toed fhoes, and difproportioned ‘head-dreffes in the ladies.
This fiyle of drefs prevailed till within thefe few years, when

od fenfe and a more juft tafle broke through the buckram
and whalebone, and produced the prefent eafy and elegant
mode of attire; which may be faid to mark a point of
national excellence. Reynolds contributed much to this
change; his whole life was a ftruggle with the hydra fafhion,
‘as his works evince.
_ ° The above ftatement will be found not to apply only to

the article of drefs, but to extend to every department. Let
us, for inftance, from the period of Henry VIII. par oe
is ip-

On Painting. 225
Ss

fhip-building, civil archite@ture, our furniture, plate, &e. &c.,
and we fhall find them to have nearly improved together, or
to have flu€tuated as the tafte for de/fin prevailed, till the pa-
tronage beftowed by his prefent majefty, by exciting a general
love for the arts, improved the national tafte to its prefent
great and highly refpectable ftate.

Before we difmifs the prefent effay we fhall endeavour to
point out fome of the advantages that refult from the prac-
tice of drawing, to thofe who do not make a profeflion of it.
Many muft be obvious from the former part of this paper.
To every gentleman who travels, it is abfolutely neceffary 5
for, independently of its teaching him to fee accurately, the
curious and ever-reftlefs eye of the artift comprehends more
at one view than the common obferver will notice in an age.
The volume of nature is laid open to him; his attention is
dire&ted to the vaft and minute; men and manners are not
concealed from his view, and his imagination clings to per-
feétion with ineffable delight. :

It is not too much to fay, that drawing opens the mind
more than years devoted to the acquiring of languages, or the
mere learning of words: it teaches to think. The artift
is a true logician: not content with producing effects, he is
ever inquiring after caufes founded on a vifible demonftration,
to exhibit them in his works.

&

ass On Painting.

.The influence it has on our moral conduct is, perhaps, |
one of the greateft recommendations for the ftudy of the arts.
Wo one can meditate on the order obfervable im nature, and
not reduce his conduét to a fimilar ftandard of regularity.
To have a juft relifh for what is elegant and proper in paint-
ing, fculpture, or archite€iure, mult be a fine preparation for
true notions relative to charaéter and behaviour. Should
fuch a one be overpowered by paffion, or fwerve from his
duty, we need not fear but he will return on the firft reflec-
tion, and with a redoubled refolution’ not to err a fecond
time: for he cannot but obferve, that the well-being of na-
ture, as well as of the individual, depends on regularity and
order; -and that a difregard of the focial virtues will ever be
accompanied with fhame and remorfe. Paffion is a whirl-
wind, that fhakes the buman frame, as the convulfions of an
earthquake diforder that of nature.

Every Briton that travels fhould propofe to himfelf plea-
fure and advantage, and his inquiry fhould enable him to
add to the national ftock of knowledge; for it cannot be faid
that he travels to enjoy the advantage of a better government,
or becaufe other nations havea greater conrmerce. Hence,
then, it muft be for arts and learning. And how is he to become
acquainted with the former without a knowledge in painting,
fculpture, and architecture, any more than he could with the
latter, without a knowledge in the languages of the coun-
tries he may have occafion to pafs through? Lord Bacon
fays: “ Travel, in the younger fort, is a part of education 5
in the elder, a part of experience. He that travelleth into a
country before he hath fome entrance into the language,
xoeth to fehool and not to travel.” The fame may be faid
of thofe who travel before they have obtained a knowledge in
the polite arts. How many noble works of architecture did
lord Burlington bequeath to his country! They remain mo-
numents of national tafte, highly honourable to his memory.
Let us be permitted to mention the honour the arts at pre-
fent derive from the matterly produtions of the earl of Ayles-
ford, fir G. Beaumont, fir R. Hoare, W. Scope, efq. of
Cattle-comb ; captain Lewis, of the royal navy ; capt. Mor-
daunt, aod many others, whofe works will ever‘rank among
the firft productions of the pencil. Lord Warwick is faid to
poffefs the true poetic {pirit for compofing heroic landfcape.
While we are recommending to gentlemen to learn to draw,
?t mutt not be underftood that we with to deprive the ladies
of the pleafure and advantage that mutt refult from: their
practifing an art that ftands, perhaps, before all others for

lanproving

4 lass On Painting. _ B27

improving our tafte, particularly in fuch things as are con-
nected with decoration.
> Though we recommend learning to draw thus generally,
we mutt fay it requires the utmoft caution in the choice of a
matter; for, fhould his abilities be confined, or his talte de-
praved, there is great danger of the poifon being conveyed
to the pupil: and if, in the end, his better underftanding rife
fuperior to the evil, he will, unfortunately, have much to
unlearn. Above all, if he be arrived at an age to difcrimi-
nate, objeéts worthy attention fhould be fet as examples of
imitation; he fhould not be amufed and his time wafted with
gew-gaws and trafh beneath the dignity and attention of
rational beings.

Eyery one is acquainted with the progrefs of what may
be termed common or fchool education. The matters begin
teaching the letters, and then proceed to fyllables, which
are joined into fentences: but the ultimate end is, com-
pofing themes to call forth the power of invention, and
convey a more exquifite idea of the language. Exatly
fo fhould be the progrefs in teaching drawing. If the know-
Jedge to be obtained be the human figure, we begin with
parts; as eyes, nofes, heads, hands, &c., which is the AB Cc.

+ This, of courfe, leads to the whole figure, which may be
rs compared to {pelling; that naturally conducts to the round,

or drawing from plaifter cafts; then from the life; and ulti-
mately to compofition. Should landfcape be the purfuit, the
progrefs is precifely the fame. We begin with parts or fingle
objects ; as trees, bridges, cottages, caftles, &c. Here again
is the alphabet. This we too quit to copy wholes, or a
combination of objeéts; and in the end we apply to nature,
‘which fets us free from our matter. Then we muft improve
‘by our own aétivity; and, like the bee, cull the honey from
‘every flower. As much of our fuccefs depends on the abili-
_ ties of the mafter, the greateft care fhould be obferved in the
_ ‘choice. He is but as a crutch to the lame; but we ought
~ ‘to make ourfelves fure it is found, and without flaw or fhake;
“that is, as far as our judgment will permit, or the opinion of

‘friends direct.
"He who afpires to a knowledge in the fine arts can only
hope to fucceed by turning his attention to the fenfitive part
of natote, baeticutacty by an inquiry after fuch objects as are
- ‘naturally agreeable, or the contrary: alfo fuch as, are grand
“or mean, proper or improper. This is the only foundation
of a juft and rational tafte, and, like morals, may be culti-
vated to a hivh degree of refinement. The fine arts, where
the feelings only are concerned, will pleafe, from their no-
; P2 velty,

\

858 Difference between Heads of Mammoth and Elephant.

velty, in the prime of life; but the delight will ceafe in a
more advanced period, when the fervour of the imagination
goes off. On the contrary, where we are governed by juft
principles and a thorough knowledge, they will afford feope
for fancy as well as judgment, they will grow into a favourite
entertainment, and their vigour will prevail as ftrong in the
evening as in the morning of life. This only can make the
arts truly delightful. It is not a few technical phrafes, picked
up from profeffional men, which may enable one to babble
like a parrot, that can at any time pleafe or be pleafing.
Science is a coy lady, and will not grant her favours without
being long courted. But, fhould we alpire to no higher cha-
racter than that of the mere critic, a fmall ftock of informa-
tion will fuffice; and practice will increafe confidence where
there is nothing to Jofe. Crriticifm is a lady of eafy accefs:
the want of meaning fhe fupplies with words; and the want
of knowledge is recompenfed with cunning. She flatters all;
and thofe whom nature has made weak, or idlenefs keeps
ignorant, may feed their vanity at her fhrine.

a

XXXIV. On the Differences which exift between the Heads

of the Mammoth and Elephant. By REMBRANDT

PEALE, E/q.*
Tu E drawings which accompany this (fee Plate V.)
are intended to explain the differences between the head of
the mammoth and that of the elephant. The teeth form the
mott firiking character: thofe of the elephant are exclufively
graminivorous, and confequently diftinguifhed from thofe of
the mammoth, which were intended for animal food of fome
kind, and not improbably fhell-fith, on the fuppofition that
the animal was amphibious }: and this may account for the
-peculiar form and pofition of the tufks. On examining the
head of the elephant, it will appear that the fockets fer the
tufks at A are fituated, with refpect to the condyle of the
neck at B, nearly in an angle of 45 degrees; fo that the
-tufks, which have but little curve, are directed downwards
and forwards, and may be with eafe employed offenfively
and defenfively. On the other hand, it will be obferved that
in the mammoth the focket A is nearly on a horizontal line
with the condyle B; and therefore the tufks, which are femi-
circular, could never have been elevated in the air, pointing

* Communicated by the Author.
+ See the former number, p. 162—169 of the prefent volume.
backwards,

On the Hydrometer. 425

backwards, but muft have been:as reprefented in the figure,
the points thrown out by the fpiral twift on each fide :—in
this pofition they might have anfwered in ftriking down {mall
animals, or in detaching fhell-fith from the bottoms of rivers,
or even in afcending the banks. .
In the elephant the orbit of the eye is fituated at C,
whereas in the correfponding part at C in the mammoth Is
a large mafs of bone, fo that the eye muft have been elfe-
where: to afcertain where, we mutt wait until we receive the
cranium lately difcovered on the Obio. The cheek of the
elephant is formed of two bones; but in the mammoth, befides
other variations, there is but one bone. The whole figure
of the under-jaw differs moft remarkably ; firft in the length
of the condyles or arms from E to B: in the mammoth it is:
fhort and angular; but in the elephant DE 8 forms a femi-
circular line, and at D it is long and pointed.
_ This fhort reference is fufficient to direct the attention of
thofe who with to examine them more critically ; when they
may remark feveral other characters fufhciently interefting,

XXXV. On the Hydrometer. By Witt1AM Speer, E/g.
Supervifor and Affayer of Spirits in the Port of Dublin.

[Concluded from p. 162. ]

| SHALL now proceed to explain Mr. Gilpin’s tables,
in order to demonftrate their ufe, and the ufe of my addi-
tional columns. The firft I cannot do better than in the
words of Sir Charles Blagden himfelf:

« Tables for reducing the quantities by weight, in any
mixture of pure fpirit and water, to thofe by meafure; and
for determining the proportion, by meafure, of cach of the
two fubftances in fuch mixtures, by Mr. George Gilpin,
clerk to the Royal Society, communicated by Sir Charles
Blagden :

«© Thefe tables are founded on the experiments, of which
the refults were given in the Report and Supplementary Re-
port on the beft Method of proportioning the Excife on Spi-
rituous Liquors. They are computed for every degree of heat,
from 30° to 80°, and for the addition or fubtraétion of every
one part in a hundred of water or fpirit; but as the experi-
ments themfelyes were made only to every fifth degree of
heat, and every five in the hundred of water or {pirit, the
jntermediate Lappe are filled up by interpolation in tle ufual
manner, with allowance for fecond differences, :

ne . ‘6 every

_

330 On the Hydrometer:

< Every table confifts of eight columns, and there are two

tables for every degree of heat. In the firft column of the fiz

of the two tables are given the proportions of fpirit and water
by weight, 100 parts of {pirit being taken as the conftant
number, to which additions are made fucceffively of one part
of water, from 1 to gg inclufively: the firft column in the
fecond table has 100 parts of water for the conftant number;
with the parts of {pirit decreafing fucceffively by unity, from
Too to 1 inclufively. +

“<< Tt muft be obferved, that each of thefe tables, occupy-
ing one page, is divided in the middle for adapting it more
conveniently to the fize of the paper; but the whole of each
page is to be confidered as one continued table. The fecond
column of all the tables gives the fpecific gravities of the cor-
refponding mixtures of {pirit and water in the firft column,
taken from the table of {pecific gravities in the Supplementary
Report, the intermediate {paces being filled up by interpola-
tion. In the third column, 100 parts by meafure of pure
fpirit, at the temperature marked at the top of every feparaté
table, is affumed as the conftant ftandard number, to which
the refpective quantities of water by meafure, at the fame
temperature, are to be proportioned in the next column.

‘© The fourth column, therefore, contains the proportion
of water, by meafure, to 100 meafures of {pirit, anfwering to
the proportions by weight in the fame horizontal line of the
firt column. The fifth column fhows the number of parts
which the quantities of fpirit and water, contained in the
third and fourth columns, would meafure when the mixture
has been completed; that is, the bulk of the whole mixture
after the concentration or mutual penetration has fully taken
place. The fixth column, deduced from the three preceding
ones, gives the effeéts of that concentration, or how much
fmaller the volume of the whole mixture is, than it would
be if there was no fuch principle as the mutual penetration.
The feventh column fhows the quantity of pure fpirit by
meafure, at the temperature in the table, contained in an
hundred meafures of the mixture laid down in the fifth co-
Jumn.”

_ From this account it will be feen, that every mixture of
pure fpirit and water poffible to be made, is analyfed pe
at every: temperature, as to render it a matter of no great dif-
ficulty to demonftrate, at a given temperature, all the grada-
tions of ftrength which the hydrometer fhould indicate. The
mode in which this has been done I fhall now explain.

The table which Mr. Gilpin has calculated for the tem-
perature of 55, is that which I have chofen, conceiving ii

or

pp = Pee

On the Hydrometer. 23%

for feveral reafons, to be the moft convenient. And as a
reference to it becomes neceflary, I have annexed this,
with the additional columns to it, by which the hydrometer

- indications of flrength are regularly deduced from the fpecifie
gravity of the fpirit at this temperature *.

In order to explain the manner in which I have caleu-
lated thefe additional columns, I conceive the eafieft mode
will be by an example.

It being underftood by the trade that the fpecific gravity
of proof {pirit at this temperature (55) is 922, I look at the
table for this fpecific gravity, and [ find that it is a mixture
of pure fpirit and water, in the following proportions, viz.
Ioo parts of the former to 81 of the latter (both by weight),
but that by meafure it is made by mixing 100 gallons of pure
fpirit with 66 gallons gg parts of water. 1 them find that the
diminution of bulk, by penetration, on the mixture by mea-
fure, (that by weight being unneceflary to attend to’in bring-
ing out the refult,) is 4 gallons 57 parts, as, inftead of pro-
ducing 166 gallons gg parts, there will be only 162 gallons
42 parts. I find next, that this mixture contains per cent. of
pure {pirit 61 gallons 57 parts.

Thefe being the proportions in the ftandard of proof, to
which every other gradation of ftrength is relative, the Rule
of Three demonftrates this relation in a manner requiring to
be explained by another example. Suppofe a {pirituous li-
quor is produced to afcertain the hydrometer indication ; on
weighing it in a phial adapted to this purpofe, I find that at
the temperature of 55, its {pecifie gravity 1s 848 5 by looking
into the table I perceive that this contains per cent. 93°18 of
pure {pirit. I then try how much more than proof this is by
fnbtracting 61°57 (the quantity which proof contains), and
I find that this has a redundance of pure {pirit, amounting to ©

31°61.

Therefore, as 100 gallons of pure fpirit require 66 gallons
99 parts of water to reduce it to proof, the redundant 31°61
will require 21°17. Add thefe, and from the amount 52°78
the diminution of bulk by penetration is to be deducted,
which, by the ratio in proof fpirit being 1°44, the refult
finally comes out, that this fpirit is 51 gallons and 34 parts
{about one-third) over hydrometer proof. The under proofs

require lefs calculation, the excefs of water per cent, over the

proportion which proof contains being all that is required.

* It may perhaps be neceffary to obferve here, that a reference to this
table is nor required in the ufe of the hydrometer L have conitructed,
fuither than to try whether it be correét. We

: P4 . ; Thefe

232 On the Hydrometer.

Thefe examples are, I hope, fufficient to explain this table.
The ufes to which it is applicable, are, that as it affords firft
an unequivocal flandard for every gradation of firength, an
hydrometer can be graduated on a certain principle; and,
fecondly, the errors of thofe that are graduated otherwife
may be difcovered by it, and we fhall no longer be obliged

to rely on a mere affertion, that the inftrament is correct, °

nothing more being required than to compare the fpecific
gravity of the fpirit with the indication of {trength which it
has demontftrated.

On confidering how far it might be practicable to fimplify
the hydrometer, I perceived that the makers of thefe inftru-
ments had fallen into two errors, which had very confidera-
bly increafed the neceffity for thofe complex additions with
which they are incumbered.

Firft, conceiving that the inftrument was to be valued
in proportion as it was capable of making minute difcrimi-
nations, (or of its fenfibility as it is called,) they have, by
attempts to increafe this beyond thofe limits required either
in revenue or in commerce, deftroyed its fimplicity.

In the conftru€tion of this infrument, the proportion of
the ftem to the ball is an important confideration: if the
former be too large, the inftrument will not be fufficiently
fenfible; and fhould it, on the contrary, be too fmall, the
number of gradations of ftrength it is capable of indicating
will proportionably be diminithed. ;

Thofe who have conftructed moft of the hydrometers now
in ufe, have run into the latter error; the ftem being dimi-
nifhed to a fize which rendered it neceffary to have recourfe
to complex additions to fupply the place of this injudicious
and unneceflary wafte of the fimple and proper power of the
inftrument.

From a great variety of experiments to afcertain the proper
proportion between the ball and ftem, I was finally fatisfied
that the latter would admit of fuch enlargement as to be ren
dered capable of meafuring upwards of 66 gradations or per
centages of ftrength, without any weight; and this fo clearly
and diftin€tly, as to convince me that its fenfibility and ac-
curacy were {till fully fufficient.

The fecond error alluded to has arifen from an attempt
to extend the power of the infirument beyond thofe limits,
which, with propriety, and confiftently with its fimplicity,
could be effected.

An hydrometer being a counterpoife to afcertain the weight
of a {pirituous liquor, may, with propriety, be compared to a

6 pair

i
,

On the Hydrometer. 233

pair of fcales*, of which there are various fixes and defcrip-
tions, to an{wer different purpofes, by which means their fm-
plicity is uniformly’ preferved. ,

On the contrary, it has erroneoufly been conceived, that
an hydrometer would be imperfect that did not, dy one means
or another, afcertain the fpecific gravity of all liquids at their
various temperatures: the fimple power of every inftruament
of this kind being confined within certain limits, this could
not be effected without additional complications of various
kinds to thofe which were added, to increafe its fenfibility,
fome ot which are certainly ingenious, but, I conceive,
highly unfit for the purpofe of revenue.

Should this ingenuity be exercifed on a pair of fcales,
which it would be proper to ufe in weighing a portion of
eight or ten pounds, and by complex additions render them
fufficiently fenfible to afcertain a few grains or fraction of a
grain, or fo extended in their power as to weigh 100 pounds,
is it not evident that the fimplicity of the balance, which is
its great recommendation, would be deftroyed ?

That which led to the conftruction which I finally fixed
on, was firft a quadrangula? fient, from which I had four
temperatures, VIZ. 35, 45,55, and 65; and the intermediate
degrees I managed with four fmall weights on the top of the
flem, each ferving for two degrees of temperature. The
inftrument having been graduated with thefe on, if the tem-
perature fhould be ¢wo degrees higher than the fcale, I re-
moved one weight, in order to lighten the inflruament equal
to the decreafe of {pecific gravity ; if four degrees, 1 removed
two weights; if jv degrees, I removed three weights ; and
if eight degrees, | removed the fourth; and two degrees more
brought me to a new {cale, or fide of the {tem : by this means
the infirument would accord with the variations arifing from
temperature, fo far as at moft to be but one degree different
from it. It was adjufted at every tenth degree of tempera-
ture.

This was evidently a confiderable progrefs towards the ob-
ject I was in purfuit of, as it not only remedied the great de-
fect of inattention to temperature which took place in the
Irith bydrometer, but, in a great meafure, the various defeéts
of the Englith revenue hydrometer, as, notwith{landing the
weights were reduced from 36 to 4, it accorded nearly with

* The aame of the ipfrument, which in ftriéinefs fhould be arcometers
(bydrometer being an inftrument for weighing water), demouftrates this
to be the principle on which it aéts; therefore in France it is called pefe
Liqueur, and by fome Englifh writers, a water-poile.

the

234 On the Hydrometer,

the various temperatures, and indicated 66 gradations of
ftrength. T perceived, therefore, that the principle would
an{wer, but that it could be improved ftill further; and after
various efforts I at length fixed on that conftruction, of which
I fhal] now beg leave to give a defcription.

This new hydrometer is made of hard brafs: the ball is
fhaped in the form of a pear, being nearly two inches in dia-
meter at its greateft dimenfion, and two inches and a quarter
in length: the lower ftem meafures one inch and a half, and
is in ihape a prifin, each fide meafuring one-eighth of an
inch: to the lower end of this a round weight is fixed, the
diameter of which is feven-eighths of an inch. The upper
fiem is in length five inches and a half, and is an oftagon,
each fide being fomewhat lefs than an eighth of an inch
wide: each of thefe fides is graduated for a temperature en-
graved on the top, the loweft being 35, the fecond 4o, and
fo increafing by five until it reaches 70. ‘The zero, or proof”
point, is marked ©, and the gradations of ftrength (numbered
at every fourth) amount to fixty-fix, and thofe fo clearly di-
fling, that at the over-proofs they will admit of a fub-divifion,
and by that means indicate a half per cent. Thefe divifions
are not at equal diftances; an error which takes place in the
prefent lrifh and feveral of the old hydrometers, but widen
in’ proportion as the {pecific gravity of the fpirit diminifhes ;
and, being graduated with {pirits of known ftrengths at every
four per cent., the intermediate per centages are adjufted by
interpolation.

To prevent any error which might arife fron: taking the
indication of ftreneth from the wrong fide of the ftem, an
index is applied on the top of it, with an opening to fhow
the figures which point out the temperature. This index,
which applies meredy to the purpofe here mentioned, may be
renioved lower to any part of the ftem, but above the furface
of the liquor, without affecting the accuracy of the initru-
ment, as neither its weight nor dimenfion is changed ; and
being of a different colour from the ftem (fanguined fteel) it
forms a contraft with it, and, as it were, points to the indi-
cation fought for, by which every danger of error in this re-
fpect is removed.

Although this is the only ufe of the index, when the tem-
perature fhall be found one of thofe eight marked on the ftem,
vel it is neceflary that the infirument fhall accord with the
four intermediate degrees between each of the adjoining fides:
for this purpofe one of two other indexes of different weights
arc occationally fubftituted for the firft one, in order to lighten

; the

:
‘
:

On the Hydrometer. 235
the inftrument fo as to accord with the decreafe of gravity

which takes ‘place in the fpirit by the increafe of tempera-

ture. Therefore the manner of ufing the inftrument is as
follows :

Suppofing the temperature to be 50, nothing further is re-
quired but to place the index No. 1 (each being marked fo
as eafily to be diftinguifhed) on the fide marked 50, and im-
merfe. the inftrament, which at once fhows the ftrength.
Should the temperature be 51 or 52, inftead of index No. 1,
ufe that marked No. 2: fhonld it be 53 or 54, ufe index
No. 3: the inftrament having been adjufted with thefe two
auxiliary indexes, in the one cafe at a temperature of 512,
and in the other 53!, thefe four intermediate temperatures
are fo accorded to, as to be either the aétual one, or within
half a degree of it. And they apply in all cafes, to the four
intermediate degrees of temperature, and no other appendage
required to enable the inftrument, in this plain and fimple
manner, to meafure fixty-fix gradations of ftrength with an
accuracy which, it is prefumed, is fully fufficient for either
revenue or commerce *. No weight requiring different im-
merfions to find out that which is the proper one; no tem-
perature omitted to create doubts, or falfe indications of
firength; no fraétion in the per centage to operate either
againft the revenue or the merchant; no gradation of flrength
left unafcertained or determined by conjecture ; no doubt re-
maining as to the correét ftrength of all the various grada~-
tions; and no fecond infpeétion and fubfequent combination
to be made, requiring the aid of, and liable to the errors of,
a fliding rule. “4

The following is a table for graduating hydrometers on a
certain and invariable principle, fhowing from the fpecific
gravity of the fpirit at the temperature 55, what the hycro-
meter indication of ftrength fhould be of every poflible mix-
ture of pure fpirit (or alcohol) and water, from the former
down to proof fpirit—N. B. This table is calculated on
the /uppofition that the ftandard of proof is 922, tempera-

_ ture 55.

* Even this half degree of temperature may be obtained by holding
the jar containiny the fpirit for a few moments in the hand.

Table

236

Is IL,
u
gh
= =p ee

a) eo 8
ve 2 Sb
Eb os
‘2S S -
a n

Sp. + W.

100 + 0},82736
1] ,62967
2|,83192
3] 983412
4 383026

400 + 51,83834
6},84037

7 384.235
8} ,84429
g} 84613:

100 + 10),84802
11] 584982
12},85158
13} 585330
14} 85499

100 +

100 + 25| 907150
26) 87284)
27} 97415
28} ,87544
29) 97671

187796
»87919
,08040)
| 88160
| 88277

too + 30
31

2

33

34

— |

354288393
63} 88507
371588619
38} ,88729
39} 85838
100 + 40},88945
41},89051
42/,59155
43} 89258

100 +

Spirit by

_
‘

17,37) 115,
13,19}116,38
19,02}117,14
19585]117599,

21,50/119,43
22,33!120,20
23,10)120,07

232901 2157.4)

100

44!,89 359

24,81/122,51
25,64:123,28
26,46.124,05
27.29 124,82
28512125559

28,951 26,36
29577,127513
30,00 127,90
31,43 128,08

> oO

==,

led

5,120.45

fF

33,08 130,23! 2,85

33:91)131 ,00}
34574131577;

35950 132,55

36139 1.3333

2,91
2,07
3,01
3,06 |

Wid VIL st VaR. dds XI.
ota yea JSS EES S/S 5
Boa) 2 jes blog 8 - eSB
BSEISRe(RE S|" SSE Sulsc..
BES. Sl 8 Shoo RIS ywlow Ss
EX ESL AIL SESS TISS ele BES
AZS6 23/3 “5b 944-51 &
100,00}38,43 2
0,11 | 99,20|37,72 61,26
0,21 | 93,58)37,01 60,14
0,32 | 97,88)36,31 58,98
2542 | 9719}35:62 5786
0,51 | 96,50|34,03 56573
0,60 | 95,82134,25 55303
0,99 | 95+1513358 54954
0,78 | 94,49)32,92 53347
0,36 93+83)32526 52340
0.95 | 93s 1831 61 51534
1,03 | 92,54130,07 50330
1,11 91,90 39533 49,26
1,19 | 91,27|/29,70 48,26
1,26 | 90.65!29,08 23
1,54 99,03 28,46 922
1,41 | 89,43!27,86 118,66 5525
1,48 | 88,83!27,26 [18,26 44,28
1,55 | 88,23126,66 |17,85 3430
1,62 87,64)26,07 17,46 4
1,68 |. 87 106,25 »49 41,40
1575 | 86,49 24,42 O48
1,81 | 85,93'24,36 39256
1,88 85,37|2 3380 3,66
1,95 | 84,82.23,25
2,01 | 84,27123,"0 36,87
2,07 | 83,73)22,16 35299
2;13 | 83,19,21,62 35912
2,19 | 82,66,21,09 34,25
2,24 | 82,14/20,57 33°41
2,30 | 81,63:20,06 258
2,36 | 81,12/19,55 31575
2,41 | 80,62)19,06 30594.
2,47 | $0,12]18,55 30,13
2,53 | 79:63}18,06 9533
2,59 | 79,14117,57 23,54
2.64 | 78,66:17,09 27375
2,70 | 78,18 16,61 20,97
2,75 | 77571'16,14 26,21
2,80 | 77,25115,68 5947

U -
765791522 24572

76,33)14,76 123,07
75986 14,31 2324
75244.13,88 | 22,54
75300 13:43 ¢ 21,01

on a certain and invariable Principle, 239

r: WH, |Ut:| Iv. | v. | Vi. | VIL | VIL) IX. | Xx. | XE
tan =
a Pn BTS 0) Ee
Ba; ' Se sie (a Otc i. SESISEa ES
ee & wis} Seles ieSea 2, 8/22 alfa s/o80
7 aol, s|/ es) 08 tsus FIEZSleSotsexlsk
¢ o w foe a] og] 45S o48 Slaazie 2s S68%\a6
2 ° Baljeadcla- {3 rs) o|& Ove mH 3 2 | “
22 )22 bs) 28) S48 2.886 8/eo ss ele a e|8 Ss
= ODPIF ELS EAE lESE) blo psf e-cles-s'P Re
Se |3PPele EZ SIS 22/5 2885 S82 sae
= = o a
Be BF Aare ae Be an mie

|
Zz
|

37222/134,11

74557|13,00
38,04 134,88 74,14|12,57
38,87|13 ,66) 3 73971|12,14

3907 0/1304 ed ae 11,72
40,52137-2 2,88]11,31
41,35138,00 72s47|10,90
2,18.138,78 72,06|10,49
43,01;139,56 a 365}10,08
435 et oT 5] 9,68
44-06,141,13 30) 529

|-——- Se EEE

45,49'141,91 3.53 6,90 E 0,40

46,31/142,70] 3,01 3] 8,51
47:14.143248] 3,66 8,12
47°97|144,27) 3.79 7274
48,791145.05 3,74 7537

49,62 2'145,84
50,45) '146,63
51 28, 147,42
§2,10148,20
52:93; 148,99] 3

53176 149,78

378
3,82
3,86
3°90
3.94

3:98

6,63
6,26
8} 5,91
5255

5320

7300 ae 0,31

54:58 )159,57 4,01 Ape 322 0,22
53°41)151535 4.06 ) 4,50 | 3,01 } 0,20
50,24 152,14] 4,10 | 65473 4,16 | 2,78 | 0,18
57:07|152593 4914 | 65,39] 3.82 | 2.55 | 0517

i]
57:89 153,71 4,18 65,06] 3,49 | 2:33 | 015
58572)154,50 4,22 | 64,73] 3,10 | 2.11 | 0,14
59:55|155-29 4526 ps 2,83 | 1,89 | 0,12
60,37\150, 08] 4,29 64,07] 2,50 | 1,67 | 0,11
61,20)156, 874 4,33 63,75 2,18 | 1,45 é

62,0311575 65] 4337
62,85'158,45| 4,40

100 + 75|,91837
F 79) 91901

771 91963 63,68,139,24 4544
— * ~— 78] ,;92024 64,51|160,04) 4547
79} 992085 65.34 160,83 4951

+ 4 192145
2205

66,16 161 62] 4554
663,091162.42 457

61,87

0,16. | 0,01 | 0,390
61,57

0,00 | 0,00 { 0,00 | Proof

N. B, When this Table thall be finally calculated, the fragtions in the fecond
*. and lafi column are to be rendered into whole numbers.

AXXVI, Me-

{ 238 J}

XXXVI. Memoir on the Supply and Application of the Blow-
pipe. By Mr. Rospert Hare jun. Member of the
Chemical Society of Philadelphia *,

Ta E blow-pipe is, on many occafions, an ufeful inftru-
ment to the artift and philofopher. By the former it 1s ufed,
for the purpofe of enamelling, to foften or folder {mall pieces
of metal, and for the fabrication of glafs inftruments: while
the latter can, by means of it, in a few minutes, fubject fmall
portions of any fubftance to intenfe heat; and is thereby en-
abled to judge of the advantage to be gained, and the method
to be purfued, in operations on a larger fcale. The celebrated
Bergman has amply difplayed the utility of this inftrument
in docimattic operations ; and with the perfection of the do-
cimaftic art the improvement of metallurgy is intimately
connected. It is by means of the blow-pipe that glafs tubes
are moft conveniently expofed to the heat neceflary to mould
them into the many forms occafionally required for philofo-
phical purpofes ; and by the various application of tubes thus
moulded, ingenuity is often enabled to furmount the want of
apparatus, which is the greateft obftacle to the attainment
of fkill in experimental philofophy.

To all the purpofes which I have mentioned the blow-
pipe is fully adequate, when properly fupplied with air, and
applied to a proper flame: but it appears that the means
which have hitherto been employed to accomplifh thofe ends
are all faulty.

The moft general method is that of fupplying this inftru-
ment with the breath. In addition to the well-known diffi- .
culty of keeping up a conftant emiffion of air during refpira-
tion, and its injurious effect on the lungs}; it may be re-
marked, that as the breath is deprived of part of its pure air,
is mixed with carbonic acid gas, and loaded with moifture,
it is not the moft fit for combuftion ; and the obvious impof-
fibility of fupporting a flame with oxygen gas, by this me-
thod, is alfo worthy of confideration.

Another way of fupplying the blow-pipe with air, is that
of affixing to it a fmall pair of double bellows. A contriv-
ance of this kind poffeffes obvious advantages over the mouth
blow-pipe; but, owing to the pervious nature of the mate-
rials of which bellows are conftructed, and the difficulty of

* Publifhed by order of the Societv.
+ In confequence of this, fonie artifts have abandoned the ufe of the
inftrument,

making

On the Supply and Application of the Blow-pipe. 239

making their valves air-tight, upwards of nine-tenths of the
air drawn into them efeapes at other places than the proper
aperture. A pair of bellows of this kind, belonging to an
artit of this city, which were confidered as unufually air-
: tight, were found to difcharge the complement of their upper
compartment in fix-fourths of a minute, when the orifice of
the pipe was open; and in feven-fourths of a minute when
it was clofed. Hence it appears, that fix-fevenths of the air
injected into the upper compartment efeaped at other places
than the proper aperture; and if to this lofs were added that
faftained by the lower compartment, the wafte would be
found much greater. As in operating with thefe machines,
_ © itis neceflary conftantly to move the foot, the operator can-~
4 not leave his feat; and, in nice operations, the motion of his
body is an inconvenience, if not a fource of failure. Bellows
of this kind cannot be ufed for fupplying combuftion with
oxygen gas; becaufe, as this air is only to be obtained by a
chemical procefs, the fmalleft wafte of it is of ferious con-
fequence; and as there is always a portion of air remaining
in them, even when the boards are prefled as near to each
other as the folding of the leather will permit, any {mall quan-
tity of oxygen gas which might be drawn into them would
be thereby contaminated.
It feems that the only inftrument hitherto ufed for the
f fupply of combuflion with, oxygen gas, is the gafometer of
the celebrated Lavoifier: but this machine, although admi-
rably calculated for the purpofes of that great philofopher, is
too unwieldy and expentfive for ordinary ufes.

Being fenfible of the advantage which would refult from
the invention of a more perfect method of fupplying the blow-
mee with pure or atmolpheric air, I was induced to: fearch
for means of accomplithing this objeét. Having obferved
_ the cheapnefs, ftrength, and tightnels, of coopers’ veffels, I
became defirous of forming an apparatus for my purpofe, by
means of hydroftatic preifure exerted within them. I foon
found that this could not be effected conveniently without
___ the ufe of leather. Obliged to refort for affiftance to this ma-
terial, [ endeavoured to apply it in fuch manner, as to remedy

the evils refulting from the ufe of it in the common kinds of
bellows. The caufes.of thefe evils appeared to be, the open-
__ ing of the pores and joints of thefe inftruments by drynefs,
__ and the tenfion to which they are fo frequently fubjeéted. 1
_ therefore determined to fubject the leather which I fhould
ule, to morfture and comprefion. In this I fucceeded, and
_, Gerived the expected advantage. from fuccefs, The refult of
; - my

240 Memoir on the Supply and
my attention to this fubject is the produétion of a machine,
of which there follows an engraving and defcription.

When it was firft fhown to the gentlemen of the Chemical
Society, fome of them beftowed on it the appellation of ga/o-

meter; but, as etymology does not authorize this name, it

has been changed for that of hydroffatic blow-pipe.

Fig. 1. (fee plate VI.) is a perfpeétive engraving of the hy-~
droftatic blow-pipe. Part of this figure is made tranfparent,
that the internal conftruction of the machine may be under-
ftood with the greater facility.

It confifts of a cafk A, whofe length is thirty-two, and
whofe leaft diameter is eighteen inches. It is divided, by
the partition B, into two apartments. The upper and external
apartment B A, is in depth fourteen inches. The lower and
internal apartment BC, is in depth fixteen inches; and con-
tains a fheet and pipe of copper EE, D, which defcend into
it nine inches, forming two equal compartments of that
depth. The fheet and pipe of copper are foldered together
and inferted into the partition B, as may be obferved at
fix. 2; where B reprefents the partition, EE the fheet of
copper, and D the pipe. The edges EE of the fheet were
flid down into correfponding joints in the flaves of the cafk
until the partition attained its proper fituation. Coopers’
flags were then paffed into the joints; and the hoops were
driven on the cafk. :

CF, fig. 1. is a pair of circular bellows. The bottom of
the cafk ferves as a bottom for thefe bellows. In the centre
of this bottom there is a hole, round which, at the diftance
of one inch from its centre, is a circular rim of wood. On
this is nailed a valve opening upwards, which may be ob-
ferved at B, fig. 3, where there is a tranfparent engraving of
the bellows. Under the valve B may be obferved:the hole,
and circular rim of wood, over which it is nailed. © the top
of the bellows, is a circular piece of wood, feven inches in

diameter and two in thicknefs. In its centre there is a hole.

one inch and a half in diameter. Around this hole there
is acircular rabbet, in which is nailed a valve, opening up-
wards. This yalve, and the rabbet in which it is faftened,
may be feen under the letter D, at the end of the rod. There
is alfo in this top, at the diftance of one inch from its peri-
meter, a circular dove-tailed furrow filled with lead, E. The
body of the bellows FF, is compofed of {trong hofe-leather
fo as to be water-tight. Before it was fixed to the other parts
of the bellows its form was that of a hollow fruftum of a

_.cone, of which the perpendicular and greateft diameter ion
* eac

Application of the Blow-pipe. 241

#ach eight inches, and whofe leaft diameter was fix inches
and a half. {It was more eafily faftened to its appendages
when of this conical form than if it had been cylindrical,
At the protuberances FF, it is diftended by two iron rings,
to which it is fewed fatt. .
___ FG, fig. 1, is an iron rod, by means of which the top of
the bellows may be raifed or deprefled. It paffes up through
the pipe D to the handle G, which is worked by the hand or
with the foot by means of the pendent ftirrup. An enlarged
view of this rod, and of the contrivance by which it is an-
nexed to the top, may be feen at fig. 3; where GD repre-
fents the rod, and H, H, H, H, flat pieces’ of iron branching
from it. Thefe are fixed to the circular rim K K in fuch a
manner as to include the rim II, of the fame metal, which
is ferewed faft to the top of the bellows. Suffictent room is
left to allow the pieces H, H,H,H, and the rim KK, to
move round without rubbing again{t the included rim IT,
or the top of the bellows.

A copper hood, with an opening in one fide, may be ob-
ferved at L, fig. 3. The rod GD is paffed through the centre
of this hood, until the flat pieces of iron H, H, H, H, come
in contaét with the flat part of it. The hole in the centre is
then luted. The hood may be feen in its proper fituation,
at F, fig. 1.

HI, fig. 1, is a fuction-pipe half an inch in diameter.
It paffes under the cafk in the direction of the dotted lines
at C, and turns up into the hole in the bottom of the bel-
lows. This hole, which is of fuch a fize as to fit the taper-
ing end ofthe pipe, is feen at fig. 3, and has already been
mentioned, together with a circular rim of wood, which,
being nailed ropnd it, prevents the end of the pipe from
touching the valve. The fuétion-pipe has a conical mouth
at I, into which is inferted occafionally the pipe J, faftened
to the hofe and fyphon K, Ll. The hofe is made of leather,
diftended by hollow cylinders of tin half an inch in diameter
and one inch in length. Thefe were coated with tar, after
which the leather was fewed over them *.

Fig. 1, MNO, mno, are pipes of delivery, furnithed with
cocks at N,n, and conical mouths at O,o. Each of thefe
pipes communicates with one of the compartments on each
fide of the fheet and pipe EE, D.

In the partition B, may be obferved the pipe Y; furnifhed

* This hofe may be made very perfe& by tarring, and covering it with
leather a fecond time; the feams of the firft and tecond coverings being
placed on oppolite fides. Flexible pipes thus prepared will be found ufe-
ful for many other purpofes befides that here mentioned.

- Vor, XIV. No. 55. Q with

242 Memoir on the Supply and

with acock. Each end of this pipe communicates with one
of the compartments above mentioned.

P is a table affixed to the cafk by means of irons, which
are at plealure flid into or out of ftaples. One of thefe irons,
and its ftaples, may be feen near the letter Q. They are
fattened to pieces of wood which run Jengthwife under the
table, and which are fo grooved as to fupport a block of wood
which flides between them. Through this block paffes the
fcrew S, which flides backward and forward in the opening
TRY. The ftand TV, which may be obferved under the
lamp, is loofely put on this fcrew, as a wheel is placed on
its axletree. It rifes and falls with the fcrew ; but is prevented
from turning round with it, by the upright ftrip of wood T.

Having defcribed the confiruction of the hydroftatic blow-
pipe, I proceed to an explanation of the principle and man-
ner of its action, and to a detail of the ufes to which it may
be applied.

Suppofe that as much water were poured into the cafk A,
fiz. 1, as would fill the lower apartment, and rife above the
partition B; one or two inches, Let fie. 4 be a reprefenta-
tion of the cafk when fupplied with this neceflary quantity
of water. When the machine is at reft, the top of the bel-
Jows, being loaded with lead, is deprefled as low as the folding
of the leather will permit, and the fmall fpace which re-
mains in confequence of this folding, between the top of the
bellows and the bottom of the cafk, becomes filled with wa-
ter, which leaks through the upper valve. Let the bellows
be extended by deprefling the handle at a. The upper valve
will {hut tight; and a quantity of water equal to the bulk,
which the bellows will gain by extenfion, will rife through
the pipe D, to the external apartment; and the weight of the
atmofphere being removed from the top of the valve in the
bottom of the cafk, the air will prefs through the fuction-
pipe 1H, lift this valve, and oceupy the vacant {pace within
the bellows. Ifthe hand be then removed from the handle,
the lead in the top of the bellows will again deprefs.it, and
the air drawn into them, being thereby compreffed, will force
open the upper valve, and afcend. During its afcent it will
receive a ftrong lateral tendency from the hood, which will
make it pafs out at the open fide of the hood, into that com-
partment which is immediately over this opening; and as by
turning the rod, this part of the hood may be brought under
either compartment, fo the air may be thrown into either of
them ; and one of them being filled with one fpecies of gas,
the other may be filled with another fpecies: nor can there
be any danger of mixture; becaufe, as the pipe D is ol

than

a

—

Segoe,

Application of the Blow-pipe. BA

than the fheet EE, any fuperabundant quantity of air which
may be thrown into either compartment will pafs up the pipe
and efcape.

In fig. 4, the bellows are reprefented as nearly depreffed,
and the air iffuing from the open fide of the hood into the
compartment immediately over it, which is about half filled
with air. The other compartment is reprefented as being
completely full of that fluid. The water is reprefented in
commotion, that the action of the machine may be ftrongly
marked; but the motion of this fluid is in reality fo gentle,
that the regularity of a blaft is not thereby perceptibly af-
fected.

If it be defired to fill both compartments with one kind of
air, without the trouble of turning the hood, by opening the
cock of communication in the pipe Y, any air which may be
thrown into either compartment will divide itfelf equally be-
tween both of them.

It muft be obvious that the air in the compartments on
each fide of the fheet and pipe of copper EE, D, fig. 4, is
fubjeé& to hydroftatic preflure, and that of courfe it will pafs
out at the pipes of delivery, unlefs ftopt by the cocks. Thefe
pipes are omitted in fig. 4, but have been already defcribed,
together with their cocks, at MNO, mno, fig. 1.

The leather and joints of the bellows are evidently fub-
jected to the weight of a confiderable column of water; but
this preffure, being external, tends to tighten them, and ren-
ders this part of the machine fo perfeét, that if the orifice of
the fuétion-pipe be clofed, it will be found impoffible to raife
the top of the bellows, without the immenfe force which
would be neceffary to produce a vacuum within them. This
would not be the cafe if the fmalleft leakage took place.

It is now time to give an account of the purpofes to which
the hydroftatic blow-pipe may be applied, and the manner
of applying it to them.

This inftrument may be employed to fupply with atmo-
fpheric air a {mall flame for the various purpofes ofthe
mouth blow-pipe. To effect this, it is only neceffary to
place a lamp or candle on the fiand TV, which is upheld by
the {crew S, fig. 1. By raifing or lowering this ferew, or by

fliding backward or forward the block through which it

pafles, the ftand may be fo adjufted, as that the ftraight
mouth-piece X will juft enter the flame. The handle mutt
then be worked until the blaft obtains the proper ftrength.
This generally happens when the water has rifen above the
partition B three or four aid If it fhould be raifed higher,

AY tag

°244 On the Supply and Application of the Blow-pipe.

the blaft may be regulated by turning the cock more or lefs
atN.

When an operation is to be performed on a fubject which
cannot be held over the table; by fixing the fmall hofe and
blow-pipe ab, fig. 7, into one of the conical mouths O, 0,
of the pipes of delivery, and, by placing a lamp or candle on
the edge of the table, an operator may, with the fabject m
his hand, expofe the proper {pot to the flame. In this way
elafs matraffes filled with liquors have been hermetically
fealed. : ?

Nothing can be more fteady than the ftrean of air emntted
by this infirament. The falling off in preffure, arifing from
the defcent of the water, does not perceptibly affect the flame
in a blaft of fix minutes duration; and, in the mean time,
the hand'e may be deprefled fo gently, that the moft ftrict
obfervation will not difcover the Jeafl unfteadinefs to be pro-
duced by it. Or, if the machine be filled with air, by open=.
ing the cock more or lefs, an equable blaft may be fupported
for more than the fpace of an hour. ,

In order to fupply the enamellers’ lamp with air by means
of the hydroftatic blow-pipe, it is only neceflary to fabfti-
tute this inftrument for the bellows commonly ufed for this
purpofe.. There will then be nothing novel in the manner
of operating, excepting, 1ft, That the relative fituation of the
flame and the pipe is to be regulated by turning the ferew S,
or by fliding backward or forward the block through which
it paffes; and, 2dly, That in leu of the frequent movement
of the foot, neceffary with the common bellows, in the fpace
of one minute, and with fifteen ftrokes of the handle, as
much air may be drawn into the hydroftatic blow-pipe as
will blow for one hour; and as the cafk and pipes are coms
pletely air-tight, the bla{t may be ftopped, or its ftrength in-
creafed or diminifhed at pleafure, by turning more or lefs the
cock of the pipe delivering the air.

The flame of the enamellers’ lamp is not ufed exclufively
for the purpofes of the artift from whom it takes its name.
It is this niodification of the principle of the blow-pipe which
is applied to the moulding of glafs inftruments. But in heat-
ing glafs with this flame, an inconvenience arifes from the
impoffibility of expofing both fides of any fubject to the fame
heat, unlefs it be contiantly turned round; for, if only one
fide of a large glafs tube be applied to the flame, the part
expofed to its action will be fuled before the other will be
foftened, and if it be turned round conftantly a much longer
time will be required to melt it. Indeed fome large tubes of
- refractory

On the Fabrication of Charcoal in the Foreft de Benon. 245°

refractory glafs, which are not to be melted while undergoing
this rotatory motion, may be readily fufed in any fpot con-
ftantly expofed to the aétion of the flame.

In order to produce a flame which fhould be free from the
inconveniences jut defcribed, I procured the oblong lamp
with two wicks W, X, Fig. 1. It may be obferved, that
thefe wicks are fixed on two plates, which flide in a groove,
in the direétion of the length of the lamp. They may there~
fore be made to approach to, or recede from each other.
This lamp being as reprefented in the engraving placed on
the little ftand T V, fo as that one of the wicks was before
the orifice of the ftraight mouth-piece, above X ; the bent
blow-pipe at W was fo adjufted to the other wick, that when
they were both lighted, and a blaft pafled over them, their
flames met each other as reprefented in the plate. The re-
fult of this was, that a much larger tube could be fufed by
the united action of two flames, than could be melted with
one of them; and the paris being more equally heated, a
bend could be made more regularly, and with lefs danger of
collapfing.

It may be preper to obferve that the machine reprefented
in the plate is much more complex and expenfive, than is
tequifite for the purpofes of the mouth blow-pipe, or ena-
mellers’ lamp, fimply. But it is expected that artafts, avail-
ing themfelves of the principles of the machine, will reject
tkofe appurtenances which are unneceilary to their peculiar
purpofes *.

[To be continued. }

XXXVII. Memoir on the Fatrication of Charcoal in the

~ Fore/t de Benon, near Rochelle. AddrefJed to the French

» Council of Mines, Nivofe 30, Year 10. By C. Frruniau-
BELLEVUE fT.

Fouex of every kind is fo fcarce in the neighbourhood
ef Rochelle, that there are few manufactories in that quar-
ter, and none of thofe which confume a large quantity of
that article can be eftablifhed. Wood is fold exceedingly
dear, and there is {carcely a quantity fufficient for diftilling
the wines of the country.

“ The coft of the machine reprefented in the plate was about twenty
dollars; but a machine fully equal to the purpofes of the mouth blow-
pipe, or enamellers’ lamp, may be made for one fifth of that fum,

+ From the Journal des sag 65.

3 It

246 Memoir on the Fabrication of Charcoal,

It is no doubt to this high price of wood, and the neceflity
of deriving as much advantage as poflible from the few fo-
refts in the neighbourhood, that we are indebted for a
method of fabricating charcoal which feems to be practifed
no where elfe. At any rate, from the filence refpeéting it in
the Colleétion des Arts et des Meétiers, and in La Nouvelle
Encyclopedie, and from the furprife expreffed by feveral per-
fons on feeing, in the market of Rochelle, pieces of char-
coal of. fuch a fize and length that they could be tied up and
tranfported in the form of faggots, there is reafon to pre-
fume that it is not known.

The Council of Mines, defirous to colle&t every thing that
can contribute to the fuccefs of the different eftablifhments
of the republic, requefted me to make known the procefs.
What I have been able to collect on the fubjeét is as fol-
lows : ——

The charcoal of the foreft of Benon is fold at Rochelle 25
or 30 per cent. above the price of every other charcoal fabri-
cated from the fame kind of oak brought from the neigh-
bouring departments. The wood of this foreft may have
fome {uperiority over that of others: it grows flowly, is hard
and heavy; but, as it appears that the fame means of fabri-
cation are not employed in other places, a fmall part only
of the great difference in the prices of charcoal can be
aferibed to this fuperiority of the wood.

The care taken to place the furnace in the centre of fur-
rounding walls, which, by checking the current of the infe-
rior air, renders the operation of charring more uniform and
more perfect, with fome other circumftances which will be
mentioned hereafter, feem to contribute in a fpecial manner
to the advantage in queftion.

The heaps of wood which are to be converted into char-
coal, are everywhere almoft difperfed throughout the forefts,
and remain expofed to the aétion of the air in every direc-
tion; but at Benon the charcoal is fabricated in chambers.

Thefe chambers are 20 feet*fquare: the walls, built of
rough ftones, united by means of earth, are 15 feet in height,
and are covered with planks and tiles, arranged in fuch a
manner, that between the planks a {pace of two inches is
left, to afford a free paflage to the fmoke.

The floor of the chamber is convex: a mafs of argillaceous
earth rifes in the centre about fix or feven inches, having be-
tween it and the wall a circular fpace two feet and a half in
breadth, and the four corners free for the fervice of the fur-
nace.

The only wood employed is oak, known under the =
; 6 9)

SKntis

- in the Foreft de Benon. di nO Say

of black oak, and very rarely white oak *. That cut within
the current year is ufed, and never that of the preceding.

The wood is ten, twelve, or fifteen years old, and the lower
part of the tree is never feparated.. It however, in. general,
does not exceed fix inches in diameter. It is cut into pieces
from three feet eight inches to four feet in length, called d:/-
lets.

They are placed upright, without being fplit, refling, with
the fide cut into a flope like the mouth of a flute, on the
mafs of earth, and in fuch a manner that they all touch
each other; thofe at the circumference only being a little in-
elined; and, contrary to the general praétice of thofe who
char wood, one ftory only is formed. Care is taken to mix
thefe billets with fmall branches; but twigs are never intro-
duced, except in the centre of the furnace, merely to kindle
it. Two cords of wood are fometimes employed at one
timet.

When the furnace is conftru&ted, and is very. round,
fiakes, a foot in height, are planted round it, at the diftance
of half a foot: it is then covered with dry grafs, ferns f, or
paleines §, to the thicknefs of four inches in every direétion ;
and over thefe is placed coal earth (terre de charboniere) to
the fame height on the fides, and to the height of 15 inches
on the fummit. In this ftate, there remains around this fo-
cus, called the furnace, the circular {pace before mentioned
of about a foot and a halfin breadth.

The earth employed is an argil mixed with calcareous
earth: it is never removed from this inclofure, where it is
baked to fuch a degree that it might be taken for afhes, with
which it is mixed. Itis then called terre de charboniere.
In other countries, it is known by the name of frafin or _fra-

fil.

Fire is applied in the centre by means of a light placed at
the end of a (tick, introduced by a paflage formed at the
lower part of the furnace. The crevices are ftopped as foon
as they appear, and the ufval praétice is followed in this re-
fpeét, that the fire may be perfedtly regular.

When the wood is charred, half a barrel of water is thrown
over it, and then jt is covered to the height of five or fix

* Thefe are varicties of the quercus robur. In this {pecies are diftin-
guithed the white, red, and black.

+ A-cord is eight feet in length, four feet in height, and nearly four
in breadth,

t Pueris aquilina. ‘
§ A kind of grafs of the genus /romus or Witicum,

Q 4 inches,

248 On the Fabrication of Charcoal in the Foreft de Benon.

inches with earth: it is then fuffered to cool for a day, and
the charcoal is taken out. This operation lafts eight days in
winter, and only four in fummer. At the latter period the
furnace is watched day and night.

The pieces of charcoal extraéted are often three inches
and more in diameter, and fufficiently long to be made. up
into bundles, which are tranfported on the backs of mules to
the diftance of five or fix leagues: the {mailer fragments are
put into facks.

This charcoal, which is very black, exceedingly brilliant,
and fonorous, has two qualities which caufe it to be much
fought for in preference to all others; it pofleffes more aéti-
vity, and lafts longer. It is attended with the inconvenience
of emitting an odour, but it is well known that this is one of
the characters of the beft charcoal.

It is preferred for the kitchen, and for ironing linen. For
the latter ufe it is put into iron boxes, called at Rochelle
flafques. lt is employed alfo by blackfmiths when they have
no common coals. That in large pieces is moft efteemed.

The latter is fold at feven or eight francs per cwt. delivered
at Rochelle; but if the fore{t of Benon were taken proper
care of, this price might be diminifhed *.

This method of making charcoal differs from that defcribed
in the Colleétion des Aris et des Metiers, thofe of Brie and
Burgundy mentioned in the Encyclopédie, and thofe in the
departments around Paris.

.1ft. By the inclofure of walls, which muft fecure the fur-
nace much better than the hurdles employed in thofe coun-
tries, and which the workman places when he thinks proper
on the fide from which the wind proceeds, this inclofure muft
render the charring wore uniform and more economical.

ad. By the care taken not to referve for firewood, as is
done in feveral places, the lower part of the wood, which, be-
ing more compaét than the branches, ought neceflarily to
furnith better charcoal. ,

3d. Becaufe the pieces of woad are longer, and twice as
Jarge as thofe employed in the other methods, and becaufe
they are put into the furnace without being fplit.

4th. Becaufe, inftead of raifing, as ufual, four or five fto-
ries, difpofed in the form of a cone or pyramid, one only is

* There are reckoned to be eighteen furnace chambers in the village of
Benon, and one at Lalaigne. The foreft was fo much deftroyed during
the revolution, that at pre(ent no more than feven or cight chambers are —
occupied. [r {carcely fupplics enough of firewood. No more than 20,000
weight of charcoal is fabricated on it. About thirty or forty years ago
it furnifhed ten times as much.

conftructed,

On the Northern Magnetic’ Pole of the Earth; 249

conftru&ted, which renders the aétion of the current of air
much more moderate, and prevents the confumption of the
wood, and perhaps of a part of the hydrogen, which it is ef-
fentially neceflary to preferve in the charcoal.

5th. By the practice followed at Benon of throwing a cer-
tain quantity of water over the furnace when the wood is
charred.. This praétice is not mentioned in the works al-~
ready alluded to.

The forefts of Chizai and Aunai, which, except that of
Benon, are neareft to Rochelle, furnifh charcoal, which is fa-
bricated alfo from pieces of wood of the fame fize, which are

ut Into the furnace in like manner without being fplit;

ut the difference in the choice of the wood, and particularly
in the fabrication, which takes place in the open air, makes
a difference of 25 or 30 per cent. in the price of the char-
coal. This difference is fometimes greater when compared
with that of other forefts.

In the procefs therefore here defcribed, there is a faving of

wood, aud at the fame time the product acquires a greater
walue.

XXXVIIL On the Northern Magnetic Pole of the Earth.
By JEROME LaLanDE *.

Ir has been known for more than two centuries, that the
magnetic needle does not point.exa€tly north, and that its
declinatton from that direétion is different in different places.
Refearches therefore have been made to determine the point
of the earth towards which the magnetic needle turns; and
this object engaged the attention of Dr. Halley in 1683, of
Euler in 1745, of Lemonnier in 1776, and of Buffon in
1788. About five years ago Mr. Churchman, a native of
America, came to Paris to induce governnrent to fet on foot
a voyage to the north pole, for the purpofe of determining
the pofition of the magnetic pole inthe north. in the year
1794 be publifhed a work, in which he propofes a theory by
which the declination of the magnetic needle can be deter-
mined for different periods and different places. I endea-
voured to compare it with the Jateft obfervations. Thofe of
which I have already fpoken in the Connoi/Jince des Tems ¢
were made at Nootka Sound in 48° 36/ north lat. and 129°
Jong. weft from Paris, in the year 1778; and the declina-

* From the Connoiffunce des Tents pour lan. xiic

t An. iv. p. 215% F
10m

#50 On the Northern Magnetic Pole of the Earth.

tion there was 19° 44’ weft. In the fuppofition that the lines
of direétion lie in the planes of great circles, and meet in
one point, I found it to be in 77° 4/ north lat. Euler in the
Memoirs of the Academy of Berlin ‘places it iv75°; Le-
monnier, in the Lois du Magneti/me, in 73°; and Buffon,
m 71°; which makes the differences to be very fmall. Eu-
Ter conceived two magnetic poles, which are not diametri-
cally oppofite to each other. The two obfervations whieh
form the ground of my calculation were made, however,
near enough to the north pole to enable us to determine it
independently of the fouth pole. Churchman places the
north pole in the lat. ef 60°; a difference which would be
too great.

The two obfervations here alluded to would give the longi-
tude of the magnetic pole in too doubtful a manner, as the
angle at the pole is too obtufe. I endeavoured, therefore, to
obtain an intermediate obfervation, and found that, in the
year 1770, at Norreton, im lat. 40° 10! north, and long. 77°
36’ weit from Paris, the declination was 3° 8’ *, From this
it would follow, that the longitude of the magnetic pole is
r10° 35! weft from Paris. The year, however, of the laft
obfervation does not correfpond with that of the two former
ones > but the difference on this account cannot be of much
importance.

«At the time of the tranfit of Venus over the fun’s difk in
1779, obferved at Hudfon’s Bay, in lat. 58° 48’ north, and
long. 96° 30’ weft from Paris, the declination of the magne-
tic needle was found to be, in that place, 9° 41’ weft t.
This gave me for the longitude of the magnetic pole only
86° weft from Paris. The mean of the two obfervations,
therefore, would be 98°. Euler makes the longitude 115°,
and Buffon 100° weft from Paris: Lemonnier makes it only
50°. But, as the parallel at fo high a northern latitude is
only of fmall extent, a more confiderable difference in lon-
gitude would have no great influence on the previous deter-
mination of the true pofition of the magnetic pole.

We can therefore admit the given data till a feries of
more accurate obfervations of the declination of the mag-
netic needle, and its variations, collected for different deter-
minate places, fhall enable us to deduce from them the va-
riations of the magnetic pole. The variations of the mag-
netic declination have been obferved at Paris for 140 years ;
but as this has not been the cafe in America, we {till want
the proper data for calculating the motion of the magnetic

* American Tranfaétions, p. 117.
+ Phil. Tranfactions 1769, p. 483.
pole:

a Se ee

‘
:

State of Vapour fubjifting in the Aimofphere. 258

pole: it feems only to appear that Churchman’s hypothefis
correfponds very little with the obfervations which I have
calenlated, and that the northern magnetic pole lies on the
north-weft coatt of Baflin’s Bay, nearly where the entrance
of Alderman Jones is to be fought for on Buache’s chart of
1782, and where Ferrer Maldonado touched in 1598, ac-
cording to a Spanifh memoir read fome years ago in the
Academy of Sciences; which, however, feems to deferve
very little credit.

XXXIX. Of the State of Vapour fubfifling in the Atmnfpbere.
By RicuArp Kirwan, B/g. F.R.S. and PRL A.
[Concluded from p. 143. ]

Tue dilatation of the moifture contained in the air has
been feparately examined by Mr. Schmidt, and he has fhowm
how from it the volume of air fatarated with moifture, fatu-
rated, I fay, at every degree of Reaumur, may be difcovered =
the refu'ts of his experiments appear in the following table of
the volume which :000 meafures at 32° of air would acquire
if faturated with moifiure at each degree of Reaumur above
32°, expreffed on Fabrenheit’s fcale *.

Reaum. Fahren. ig Reaum.} Fahren. a
1? | 34°25° 1010°56 70°25° | 112268
36°5 1010°78 72°5 1132°25

38°75 | 1016°45 74°75 | 1142°53

4I° 1022°21 || 20 yn i i

5 | 43°25 | 1028'58 | 79°25 | 1164°02
45°5 1034°97 81°5 1175°23

|) 47°75 | 1040°41 83°75 | 118652

SI ages 1048°52 | 24 | 86: 1198°59
52°25 {105626 || 25 $8°25 | 121144
10 | 54°5 1064°72 90'5 1223°65

56°75 | 1071-28 | 92°75 | 1279°62
1z2 | 59° 1078°52 | 28 | 95°. 137'7°0g
61°25 | 108711 97°25 | 1494°02
63°5 1095°75 || 30 99°5 1610°O2
15 | 65°75 | 1104°46 ro175 =| 1725°49

16 | 68° Tit3°21 ] 32 | 104" 1849°96
33 10625 | 1983°42
* To prevent miftakes, it muft be noted that this table is not meant to
éxprefs the dilatations of air faturated at any particular degree of leat it
would acquire at other fuperior degrees, but only the bulk that 1000 parts
ary air ar 322 would acquire by faturation at cach higher degree.
Note.

952 Of the State of Vapour

Note.—1mo. Hence we fee that air faturated with moifture
at high heats is much more expanded than dry air of the
fame temperature, as De Luc and general Roy have alfo ob-
ferved ; but in temperatures below 36°5° dry air is more di-
Jatable ; which probably induced Sauffure to conclude it was
fo at higher temperatures. At 54°5 the difference is very
perceptible; for 1000 parts dry air at 32° are expanded at
54°5°, that is, by 22°5° above the freezing point to 1044°67 5
whereas 1000 parts of air faturated with moifture are ex-
tended to 1064°72, and in higher heats, the differences of
expanfion are incomparably greater.

ado. Hence it is plain why moift air, fuch as that of the
Weft Indies, is much more fuffocating than dry air of the
fame temperature: for 1000 cubic inches of~air, faturated
with moifture at 86° of Fahrenheit, contain nearly 76 inches
of moifture which is ufelefs to refpiration.

_ 3tio. Thefe experiments agree with thofe of general Roy in
which fteam was introduced at hazard; for the general found
that from 32° to 52° each degree gave at a mean 2°588, and
confequently thefe 20° would expand 1000 inches to 1051°763
and by Schmidt’s experiments, much more accurately made,
we have 1050'33. ’

4to. Schmidt alfo obferved a peculiarity in the expanfion
of moift air, previoufly noticed by Roy; for Schmidt found
that the expanfibility of air, faturated with moifture, was
fmaller than the expanfibility of pure vapour until the 167th
degree of Fahrenheit; but in higher degrees they conftantly
approached nearer to each other. And the general obferved
that the mean rate of expanfion, which from 152° to 172°
of Fahr. was 12 for each degree, did, from the 172° to the
192°, increafe to 17°88 for each degree, and increafed fill
more after the 192d to the boiling point. The fluggifhnefs
of expanfion of air, faturated with moifture at about 32°, was
alfo noticed by the general; and he hence concludes the
mean rate of expanfion from o to 32° of Fahr. to be 2°27
for each degree, which is fmaller than that of drier air.

Thefe variations of the rates of expanfibility of moift air,
faturated at different temperatures, Schmidt very juftly attri-
butes to the variation of the degrees of affinity or adherence
of air and vapour to each other at different temperatures. At
32° Fahr. it is very firong, and alfo below thatdegree; and
hence the ftrong folvent power of air colder than the water. it
a&ts upon, remarked by Richman: but if both are equally
cold, very little moifture will be taken up by the air, as al-
ready mentioned: and hence I have faid that air diffolves

; vapour

Suififting in the Atmofphere. 253
Vapour when this is in a nalfcent ftate. But in heats above
167° or 170° air and vapour are difpofed to feparate.

5to. Hence we may deduce the impoflibility of difcovering
a co-efficient univerfally applicable to exprefs the rate of ex-
panfion of air in every ftate of moifture, as Tremley has well
noticed. (See Saujfure Voy. aux Alpes, ii. 4to.) This muft
vary with the mean ftate of hygrometers above and below the
heights to be meafured: and experiments of this kind have
not yet been made. De Luc’s co-efficient anfwers tolerabty
well for very dry air, that is, whofe faturability is greatett ;
fir George Schuckburgh’s, for air much moifter; and gene-
ral Roy’s, for air ftill moift, that is, whofe faturability is
fmalleft. Hence each fucceeds. in certain cafes, and fails in
others. The dilatation or contraétion which air faturated
with moifture at any one given degree of temperature receives
without the addition of any more moifture, at any higher
or lower degree of temperature, has not.as yet been difco-
vered: for Schmidt, who alone has attempted it, is juftly
diffident of the correctnefs of the table he has given of it;
and, in fact, it is not grounded on the indication of any
known hygrometer, and improperly fuppofes the 50th degree
to indicate the mean betwixt the loweft and faturation :
whereas the 65th degree on Sauffure’s indicates that mean ;
and 98, and not 100, indicates faturation.

According to Mr. Watt (as ftated by De Luc, Meteorolo-
gy, ill. p. 145), the fpecific gravity of pure vapour is to that
of airas 4 tog. I fuppofe he compares it with air at the
ufual denfity of 30 or 29, and at fome particular temperature
which is not mentioned ; for at high temperatures the differ-
ence muft be much greater, as appears by the foregoing tables.

M. Sauffure (Hygrometer, p. 284,) has given us the fpe-
cific gravity, not indeed of pure vapour, but of vapour dif-
folved in alr, with more precifion ; for he tells us, rmo. That
a cubic foot of perfe&tly dry air has its volume augmented by
<;th, when faturated with ten grains of moifture at about
65° Fahr. of heat, and barometer 28°77 inches (Englith).

ado. That a cubic foot of pure or perfeétly dry air of that
denfity and at that temperature weighs 751 grains (French) ;
and after diffolying 10 grains of moifture, by which it is di-
Jated ..th, this new volume weighs 751 + 10 = 761 grains:
but a cubic foot of pure air, augmented by an acceffion of
1-4th of its bulk of pure air, would weigh 751 + 7-751 =
765 grains, that is 14 grains more. Hence he infers that,
in this cafe, the fpecilic gravity of the diffolved moifture is te
that of dry air‘as 10 to 143 for 74th of a cubic foot in the
one cafe weighs 10 grains, and in the other 14 grains pa

~ But

254 _ On the State of Vapour

But I ftrongly fufpect that the original experiment, on

which this calculation is founded, is erroneous, chiefly by
reafon of the ftrong adherence of moifture to cold glafs, as
will hereafter be feen in treating of dew. From Schmidt’s
experiments it may be inferred that the fpecific gravity of
vapour, diffolved in air at this temperature, is much lower
with refpeét to that of pure air than Sauflure has ftated ; for
he tells us that about 1066 meafures of dry air in tempera-
ture 65°, would, if faturated with moifture at that tempera-
ture, occupy the fpace of about 1100 meafures, and confe-
guently receive an augmentation amounting to about 4d of
their bulk: now, transferring this ratio to the cubic foot in
Sauffure’s experiment, it appears that ~',d of a cubic foot thus
added to the cubic foot of dry air weighs 10 grains; but a
eubic foot of dry air, augmented by an acceflion of ,';d of
fimilar air, would weigh 751 + 23°46 grains, which ap-
proaches nearly to Mr. Watt’s ratio: therefore the {pecific
gravity of vapour diffolved in air at this temperature is to that
of perfectly dry air as 10 to 23°5 nearly. It fhould however
be recollected that M. Sauflure found that a cubic foot of
dry air in reality took up 11°069 grains of moifture when
faturated at this temperature, and that it was only by way
ef conceffion to thofe againft whom he argued, that he ftated
the weight taken up at 10 grains; then we fhould have of
11°069 to 21°195, or, in round numbers, as 11 to 21, or 10
to ig. And it fhould further be remarked that the tempe-
rature is given very loofely, for it is fiated to be from 14 to
15° or 16° of Reaumur. See Hygrometer, p. 104 and 284.
_ Sanflure has given usa table, by the belp of which the
abfolute quantity of vapour at any barometrical height, in a
cubic foot of air, being known, the proportion ae abfolute
ganity in a cubic foot, at another barometrical height 3°6
inches lower, may be known from the mercurial height 28°77
to that of three inches and one-half nearly,

This table I here give, adapting it to our meafures.

Barometer Thus, fuppofing the abfolute quantity
of diffolved vapour at any temperature,
28°77 | 1°0000 | and barometer 28:77 to be 10 grains
25°17 | 0°9528 | per cubic foot; then the quantity of
21°57 | 0°8899 | vapour-at a height at which a baro-
17°97 0°8264 | meter would fttand at 25°17 inches
14°37. | .0°7629 | would be 10 X 0'9528 = 9'528, and
10'77 | 0°6887 | at the height at which a: barometer
7°17 | 0°6230 | would ftand at feven inches, the quan-

|. 3357) CASI tity in a cubic foot would be only 10
XK *62g0 =.6'23. But itill it is fuppofed that at thofe great
; heights,

Katio,

fubjifting in the Atmofphere. ang

heights, at which barometers would ftand fo low, that the
air is of the fume temperature as the original experiment is
made at, namely in this cafe, as it is found at barometer
28°77 inches; but fince in reality air at great heights is ge-
nerally much colder than below, to afcertain the real pro-
portion of vapour at thofe heights it will be neceflary to find
the quantity of vapour which a cubic foot of air is capable of
holding at that temperature barometer 28°77, and the ratio
which the quantity or weight of vapour actually found, bears
to the complement at that temperature. Then, 2do. to find
the complement of a cubic foot of air at the temperature
which prevails at the given barometrical height, and dimi-
nifh it in the fame ratio in which it was found diminifhed
below ; and finally, diminifh it {till further in the ratio which
that barometrical height demands. An example will fully
explain this rule.

Thus Sauffure found, barometer 28'77 and thermometer
82° of Fahr., a cubic foot of air contaimed about Lo grains
of moifture at. Geneva. Now the complement of 82° is
nearly 15 grains, and the ratio of 10 to 151s}. Then at
Mount Blanc, on the fame hour, the barometer ftood at 16°
and the thermometer at 26:8°: the complement of a cubic
foot of air at this temperature is 5°3 grains, which diminithed
in the ratio of 2 to 3 becomes 3°53; and this, further dimi-
nifhed by the ratio which the barometrical height of 16
inches demands, namely -78 = 3°5 X *75 = 2°7 grains, by
obferyation it was found to be 1:7 : the difference is only one
grain. Voy. aux Alpes, § 2007. Wow the temperature which

reyails at thofe great, heights, may be found, will be fhown
in the fequel.

The celebrated Lambert of Berlin (Mem. Berlin 1772,)
has alfo given an eflimate of the proportion of vapour which
prevails in the atmofphere at different barometrical heights,
deduced from calculations founded on many fictions—fuch
as that of a homogencous atmofphere, of pure air diftinét
from common air, and an erroneous fyftem of the afcent of
heat; yet, as it is much eafier in its application, and in the
inftance juft quoted approaches very near the truth, I have
calculated the refults at his fyftem, which is nothing more
than that the quantity of vapour at different barometrical
heights above the earth is in the ratios of the {quares of thofe
heights. By a homogeneous atmofphere it is probable he
meant fuch a fiate of the atmofphere as prevails tn ferene
unclouded weather; and it is certainly only in fuch an at-
mofphere that any calculation can be inflituted.

Table

256 On the State of Vapour

Table of the Ratios of the Quantities of Vapour at different
barometrical Heights, the Quantity at the Surface of the
Earth being given. ;

Ratio of | Ratio of B Ratio of
Barometer. Vapour. | Barometer. Vapour. | Barometer. | Vapour.

24° 15762 12 144

30° goo |

29°5 870 |! 23° CL ae |e 121
29. 841 | 22 484 10 100
28°5 | 812 | a1 44. 9 8I
28° 784 || 20 400 8 64
ee 9 | 361 fae 49
27° 929 -|| 18 324 6 36
26°5 | 702 | 47 | 289 | 5 25
26° 676 || 16 256 | 4 16
25°5 659 | 15 225 |i 3 9
25° 625 || 14 196 | 2 4
24°5 | Goo | 13 169 I 1

‘Thus, in the example laf quoted, the quantity -of vapour
in a cubic foot at Geneva being 10 grains, barometer 28°77,
the quantity on Mount Blanc, barometer 16, fhould be *3093
for as 827°7 (= 28°77') is to 256 (= 16°), fo is 10 to0°309,
which differs from the truth by only 0*391 of a grain.

As vapours unite to air, partly through the agency of heat,
and partly through that of affinity and of ele€tricity, fo they
feparate from it, fometimes from a diminution of that degree
of heat which they poffeffed in their nafcent ftate, fometimes
from a diminution of affinity, and fometimes from an altera-
tion in their eleétrical ftate. ioe

In their firft degree of coalefeence when feparated from
air, they form aggregates of exceeding minute particles, fe- |
parated from air by the diminution of affinity, and alfo from
each other by electrical atmofpheres: thefe aggregates are of
equal and often lower fpecific gravity than the air in which
they are formed, and yet are vifible by reafon of their opa-
city; when near the earth, they are called fogs, mzffs, or
haze, (which differ only in denfity,) and when at greater
heights, clouds. ,

Vapours iffuing from water or moifture warmer than the
air to which they unite, are foon cooled by it, and thence in
great meafure difmiffed: hence the morning mifts obferved
in fummer and the winter mifts of the colder regions: even-
ing mifts, on the contrary, proceed from the fuperfaturation
ef air with vapours previoufly diflolved, arifing from the fu-

pervening

Subjifting in the Atmofpbere. . 259

pervening decreafed temperature. The inferior ftrata of the
atmofphere are fcarce ever fuperfaturated by vapours arifing
from water or moifture warmer than the air into which they
afcend ; for; before the point of faturation can be attained,
their affinity to the portion of air to which they are united is
weakened, and thence exceeded by the unincumbered affinity
of the fuperior ftrata: and this happens fucceffively on to the
higher regions ; but with diminifhed activity, by reafon of
the diminifhed denfity of the higher ftrata, until their ulte-
rior progrefs is checked by faturation; but as they are {till
continually recruited from below, their quantity is at laft fo
far increafed that they coalefce into clouds. Here the pro-
cefs recommences; for from the furface of thefe clouds a
frefh evaporation often takes place, which, after fome pro-
grefs, is again checked in its turn, and clouds are formed at
a fuperior height: thefe again give room to a further evapo-
ration, and a new ftage of clouds is formed, until the procefs
is at laft arrefted by the intenfe cold of the fuperior regions.
But the mere cold of congelation is not fufficient to arreft it;
for Bouguer informs us that clouds are formed 2500 feet
above the lower line of congelation, and that ice itfelf eva-
porates, though cooled, feveral degrees below the freezing
point, is well known. The diftance of the particles, both
of air and vapour, from each other, when fo far rarefied as
they muft be in the fuperior regions of the atmofphere, pre-
ig their coalefvence in any but the extreme degrees of
cold.

Hence we fee that in the warmer latitudes and feafons va-
rious ftrata of clouds may be formed one above the other:
Mufchenbrooek attefts that even in Holland, in Auguft 1748,
he diftinétly difcerned three. Thefe diftin& ftrata, varioufly
electrified and otherwife circumftanced, give occafion to va-
rious phenomena, the detail of which would here be mif-

vel

The clouds which commonly crown the fummits even of
Jow mountains, and often announce rain, are caufed by the
near approach to faturation at thofe elevations, and its aétual
attainment through the evaporation from thofe fummits.
But the fummits of the loftie(t mountains ever crowned with
fnow, are generally fhrowded in clouds, from the cold they
impart to the air in contaét with them, and the lofs of elec
tricity conducted away from the vapours contained in that
air by the mountain.

The heights at which the loweft clouds are formed, are
various in various latitudes and feafons; greater in the
warmer, and fmaller in the colder. In latioude 54° in Cum-

Vou, XIV, No, 55. R berland,

255 On the Specific Gravity of the Coals

berland, Mr. Crofthwaite obferved none lower than 2706
feet, and none higher than 3150, in the courfe of feveral
years *. But this country being mountainous, they are pro-
tobi Jower than m others under the fame parallel. Lam-
bert, in Berlin, latitude 52° 32’, in the month of July 1773,
found their height 7792 feet; thermometer 65°, and the ba-
rometer fomewhat below its mean height +. Schuckburgh
alfo remarks that clouds frequently reft below the fummit
of Saleve, whofe height is 2831 feet. Phil. Tranf. 1777,
p- 538; and Gentil, at Pondicherry, latitude 12°, obferved
fome at the height of 10240 feet. 11. Voy. p. 79.

The weight of clouds Sauffure efiimates at one-third or
one-fourth of that of the cubic foot of air in whieh they fub-
fift. Hygrometer, p. 270. When the barometer rifes, clouds:
are partly diffolved, as denfe air is a better folvent than rarer
air, and partly rife higher m confequence of the increafed

fpecific gravity of the inferior air; when the barometer falls,
the contrary takes place.

XL. Report, read before the Conference of Mines, on the
Specific Gravity of the Coals of several Mines of France;
and on the Difference in the increafe of Volume which they
acquire by Humeéation. By C. BhaviEer, Engineer f.

a)
‘T HE conference of mines had long been fenfible of the
neceflity of determining, with rigorous precifion, the fpecific
gravity of coals in maffes or in large fragments, in order that
it might be compared with that of the fame article as fold by
the coal merchants. This objet was at the fame time of
‘more importance, as it would make known what difference
humeétation would produce on the volume which coals oc-
cupy in their ftate of drynefs,
C. Duhamel and Blavier propofed to accomplifh this
_ object in. the execution of a labour with which they were
charged, in order to confirm the different affertions already
eftablifhed by one of them, in a memoir delivered to the
conference on the 121h Pluviofe, year 7.
Thefe comuiffioners wifhed to take as a fixedand invariable
bafe, the /olzd coal, or {uch as it is when extraéted from the
inine, that they might afterwards proceed progreflively te
‘that reduced to different degrees of attenuation, and particu-
~ * J)’ Alton’s Meteorological Gblervations, p. qt.
+ Mem. Berlin 1773, p. 44.
+ Fsom the Yourxal des Mines, No. 65.—We have inferted this paper

as it may furnith ufciul hints for fimilar experiments on the varieties of
~ wal in Britain, which are {9 numerous.

larly

of feveral Mines of France. 259

latly to thofe’ which it experiences till the moment when
it paffes into the hands of the confumer: but they were ob-
liged to confine their experiments to each of thofe kinds of
coal placed at their difpofal by the council, and which were
tranfmitted to them directly by the workers of the mines of
Creuflot, St. Etienne, Lataupe, Lubarthe, Lacomballe, and
Decife.

The method by which they were able to afcertain the fpe-
eific gravity was as follows:

After bringing the different kinds of coal above mentioned
to the uniform fize of peafe or beans, by fifting them, and
having carefully picked out all the earthy or fchiftous parti-
cles, the commiffioners filled a decalitre with each of them,
taking care to choofe thofe in the higheft ftate of drynefs,
and to pour them in without any flock, as merchants do
who meafure them on the ground or in their barges. The
weight of each deealitre being alcertained, the dry coal con-
tained in the veffel was then watered in fucceffion without
fhaking or difplacing it; and this was continued till the water
floated over the furtace. The coals thus moiftened were again
weighed, and the difference of weight indicated the fpecific
gravity required, fince this article is impermeable to water,
which only fills up the vacuities left between the grains of
the bruifed coal by their uniting under a greater or lefs ob«
tufe angle.

In regard to the increafe of weight arifing from humeéta-
tion, it will be fufficient to decant the fupernatant liquor ;
and the difference of the two, weighed as above, exprefled
this fecond refult.

They then moiftened fucceffively, and in different propor-
tions, each kind of coal; fuffered the fuperfluous water to
drain off for a quarter of an hour; and, comparing the vo-
Jume of the dry matter with that which it occupied at dif-
ferent degrees of humectation, were able to difcover the pro-
greflive increafe or diminution by employing for this purpofe
a wire placed exactly level with the furface of the veffel.

The table annexed exhibits the feries of the comparative
experiments: indicating for each heétolitre of the kinds of
coal before mentioned the weight of that article in its ftate
of drynefs; that of the water introduced, which may be
confidered as folid ; the increafe of weight in the moiftened
eoals; the augmentation of its volume arifing from greater
or lefs humeétation; the number of parts of folid coal in a
hundred parts of dry coal, and the fpecific gravity of the latter.

It follows, from the labour of C. Duhamel and Blavier,
rft, That the increafe of weight is always in the direét ratio
ef the quantity of water added, which itfglf increafes accord-

° R2 ing

260 On the Specific Gravity of the Coals

ing to the degree of the trituration of the coal, and in the
inverfe ratio of the fpecific gravity of the article. ad, That
the latter alfo is in the inverfe ratio of the weight of the liquid
which the dry coal retains after decantation. 3d, That the
increafe of volume is the more fenfible as a greater quantity
of humeétation has been produced; and that there exifls a
term at which the addition of water occafions no change, |
and beyond which the volume decreafes in determinate pro-
portions. 4th, In the laft place, that all thefe refults vary
not only in regard to the different kinds of coal, but even in
the fame kind of coal, according to its nature, its mixture
with parts more or lefs earthy, and particularly its fize or
degree of trituration.

The moft natural eonclufion to be deduced from thefe ex-
periments is, that in the fale of coals there may be imtroduced
abufes, which it will be of more importance to reform, as in
100 parts of dry coal there are fearcely 70 parts of folid coal ;
and befides, it is proved, that from humeétation carried to a
certain degree, there may refult an augmentation or diminu-
tion of volume to the lofs of the confumer or even of the
merchant himfelf.

In confequence of thefe confiderations, ©. Duhamel and
-C. Blavier, in a report dated Pluviofe 8, year 10, have con-
eluded that the fale of coals by weight is attended with the
fame inconveniences as thofe which take place in a deter-
minate meafure of capacity. They perfift in believing that
the combinations of the two methods could not be employed
but on the fuppofition of coal entirely dry, and yet by ex-
preffing a wifh that an accurate table of the fpecific.gravities
of all the coals in France, comparing them with each other
in different degrees of fize and humeétation, might be drawn
out. The refultswould at leaft be approximative data, by
help of which \it would be poffible to expofe the fhameful
traffic of fome coal-merchants, who alter the nature of their
commodity by mixtures more or lefs earthy.. This labour
would be particularly important were it accompanied with
experiments proper for determining the real value of coal in
regard to the ule for which it is bett fitted, Itas thus, for
example, that C. Blavier has already found, by repeated
trials, that the pera of Decife muft be felefted to ‘heat rever-
berating and evaporating furnaces in preference to the fmall
coal of St. Etienne; while the latter, which is fold in general
for at leaft a fourth more, may be employed with advantage
in forges and in all circumftances where a ftrong eoncen-
trated heat is required. The mixture of thefe two kinds of
coal, in the proportion of four to three, gave him an article
of fuel the more valuable, ,as, by furnifhing a more ma

} ; an

261
to the confumer a

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[ 262 J ‘

XLI. Memoir on the Wax-Tree of Louifiana and Pennfyl-
vania. By CuHaxves Louris CaveET, of the College of
Pharmacy *. ode

A NumseEr of plants, fuch as the Croton febiferum, the
Tomex febifera of Loureiro, the poplar, the alder, the pine,
and fome /abiati, give by decoétion a concrete inflammable
matter, fimilar, in a greater or Jefs degree, to tallow or wax;
that is to fay, a fixed oil faturated with oxygen. The light
down, called the bloom of fruits, and which gives a fil-
very appearance to the furface of plums and other {tone fruits,
is wax, as has been proved by M. Prouli. But the tree
which furnifhes this matter in the greatett abundance, and
which in many refpeéts deferves the attention of agricul-
turifts, chemifts, phyficians, and commercial men, is the
Myrica cerifera, or wax-tree.

We read in the Hiftory of the Academy of Sciences for
the years 1722 and 1725, that M. Alexandre, a furgeon and
correfpondent of M. Mairan, obferved in Louifiana, a tree
of the fize of the cherry-tree, having the appearance of the
myrtle and nearly the fame odour, and bearing a feed of
the fize of coriander. Thefe feeds, of an afh-gray colour,
contain a fmall offeous ftone, pretty round, covered with
fhining wax, which is obtained by boiling the feeds in water.
This wax is drier and more friable than ours. The inhabi-
tants of the country make tapers of it. M. Alexandre adds :
« This feed has commonly a beautiful lake colour, and on
being bruifed with the fingers they acquire the fame tint;
but this takes place only at a certain feafon.”

The liquor in which the feeds have been boiled, and from
which the wax has been taken, when evaporated to the con-
fiftence of an extra&t, was found by M. Alexandre to be an
effetual remedy for checking the moft ob{tinate dyfenteries.

The advantageous properties exhibited by this tree could
not but induce {cientific men to make refearches for the pur-
pofe of afcertaining the varieties of this vegetable production,
and what care was required in its culture, It was long con-
fidered as a mere object of curiofity.

Linnezus, in his Vegetable Syftem, fpeaks only of the
wax-tree of Virginia (Myrica cerifera), with jeaves lanceo-
Jated as if indented, ftem arborefcent.

Having requefted C. Ventenat to inform me how many
fpecies there are of it, he replied that Ayton has diftinguifhed
two, Viz.

* From the Annales de Chimie, No, 131.

xh, Myrica

On the Wax-Tree of Louifiana and Pennfylvania. 263

1ft, Myrica cerifera anguftifolia, which grows in Louifi-
ana. This tree is delicate, flowers. with difficulty in our
green-houfes: its feeds are fmaller than thofe of the fol-
lowing.

ad, Myrica cerifera latifolia, which grows in Pennfylva-
nia, Carolina, and Virginia. It does not rife ta fuch a height
as the former, and is perfeétly naturalized in France. Thefe
two Myrice are of the family of the diacz.

They are both cultivated at the Mu/feuwm des Plantes and
in the gardens of C. Cels and Lemonier.

C. Michault admits a third {pecies of Myrica cerifera, which
he calls the dwarf wax-tree. C. Ventenat thinks that wax
may be extracted from all the Myrice.

The authors who have fpoken of thefe trees with fome de-
tails are C. Marchal, tranflated by Leferme, Lepage-Du-
prat, and Tofcan, librarian of the Mufeum of Natural Hif-
tory. A memoir inferted by the latter in his work intitled
L’ Ami de la Nature, makes known the manner in which
vegetable wax is collected in the colonies.

** Towards the end of Autumn,” fays he, * when the
berries are ripe, a man quits his home, with his family, to
proceed to fome ifland, or fome bank near the fea, where
the wax-trees grow in abundance. He carries with him
veffels for boiling the berries, and an axe to build a hut to
fhelter him during his refidence in that place, which is ge-
nerally three or four weeks. While he 1s cutting down the
trees and conftruéting the hut, his children colleé& the ber-
ries: a fruitful fhrub can furnifh about feven pounds. When
the berries are collected, the whole family employ themfelves
im extracting the wax. A certain quantity of the feeds are
thrown into the kettles, and water is poured over them in
fufficient quantity to rife to the height of half a foot above
them. The whole is then boiled, ftirring the feeds from
time to time and prefling them againft the fides of the vef-
fels, that the wax may more eafily be detached. A little
after, the wax is feen floating in the form of fat, which is
colleéted with a fpoon and ftrained through a piece of coarfe
cloth to feparate the impurities mixed with it. When no
more wax detaches itfelf, the berries are taken out by means
ef a tkimmer, and new ones are put into the water; taking
care to renew it the fecond or third time, and even to add
more doi/ing water in proportion as itis confumed, that the
operation may not be retarded. When a certain quantity of
wax has been colleéted in this manner, it is placed on a piece
of linen cloth to drain, and to feparate the water with which
it is ftill mixed. It is then dried, and melted a fecond time

R4 for

264 Memoir on the Wax-Tree

for the purpofe of purifying it, and is moulded into the form
of cakes. Four pounds of the feeds give about a poind of
wax. That which detaches itfelf firft, is generally yellow,
but in the laft boilings it affumes a green colour, in confe-
quence of the tint communicated toit by the pellicle with
which the nucleus of the feed is covered.”

Kalm, the traveller, {peaking of the vegetable wax, fays
that in countries where the wax-tree grows, it is employed
for making excellent foap, with which linen can he perfectly
wathed.

Such was the knowledge naturalifts had of the myrica, or
at leaft no other obfervations, as far as I know, had been
publithed, refpeéting it, when a naturalift gave me half a
kilogramme of the vegetable wax of Louifiana. I was defir-
ous to analyfe it, and compare it with the wax made by our
bees, but before I undertook this labour, I wifhed to be ac-
quainted with the nature of the fhrub, and of the feeds of the
myrica. I faw this valuable produétion in the Jardin des
Plantes, and wrote to C. Defhayes, a zealous botanift, who
fuperintends at Rambouillet the cultivation of the Myrica
penn[ylvanica, to beg he would give me a few details on that
fubjeét. He was fo kind as to return an anfwer, accompa-
nied with fome of the feeds, which I took the earlicf op-
portunity of examining. ‘

This feed is a kind of berry, of the fize of a pepper-corn 3
its furface, when it is ripe and frefh is white, interfperfed
with {mall black afperities, which give it the appearance of
fhagreen. When rubbed between the hands, it renders them
unctuous and greafy.

If one of thefe {mall berries be ftrongly preffed, it divefts
itfelf of a matter in appearance amylaceous, mixed with fmal
round grains like gunpowder. The nucleus, which remain]
bare, has a very thick ligneous covering, and contains a dis
evtyledon kernel. By rubbing a handful of the berries on a
hair fieve, I obtained a gray duft, in which I could diftin-
guith, by the help of a magnifying glafs, the fmall brown
grains already mentioned, in the middle of a white powder.

I put this powder into alcohol, which by the help ofa
gentle heat, diffolved all the white part, and left the black
powder, which I collected a-part. Water poured over this
alcoholic folution, difengaged a fubftance which floated on
the furface of the liquid. J melted this fubftance, and obtain-
ed a yellow wax, fimilar to that brought me from Lovifiana,
This experiment was fufficient to prove that the wax of the
myrica is the white rough matter which envelopes the feeds.

The black powder which I feparated appeared to me to

contain

of Louifiana and Pennfylvania. 265

contain a colouring principle, and I did not defpair that f
fhould find in it the beautiful lake, mentioned by M. Alex-
andre. With this view, I bruifed ftrongly the powder, and
boiled it in a folution of acid fulphate of alumine. I was
much aftonifhed to obtain nothing but a liquor fcarcely co-
loured, and the alumine precipitated by an alkali, was only
flightly ftained.

I took another part of this black bruifed powder, and_ put
it to infufe in alcohol. I foon obtained a tincture of the co-
lour of wine lees: on heating this tin€ture, it became as red
as a ftrong tinéture of cinchona or cachou. This refit in-
duced me to believe that the colouring principle was refinous,
but by adding water I faw no precipitate formed.

I poured into this tin@ture water charged with fulphate of
alumine; a flight precipitate was produced : a folution of ful-
phate of iron roid it immediately into an ink.

What is the aftringent colouring principle which is not
foluble in alcohol, which forms no precipitate with water,
and which has fo little attraction for alumine? To find it a
feries of experiments, which the few fubftances I had in my
poffeflion did not permit me to make, would have been ne-
eeflary. The aftringent matter mentioned by M. Alexandre,
mutt be found in the decoétion of the unbruifed feeds. To
afcertain this fa&t, I boiled the feeds in a filver veffel. The
deco&tion on which a little wax floated, was of a greenifh
colour, with a tafte fomewhat ftyptic : it precipitated ferru-
ginous folutions black. Having heated it im a very clean iron
veflel, it {peedily became black. To know whether this pro-
perty arofe from the gallic acid alone, or from tannin, I
mixed a little of the concentrated decoétion with a folution
of gelatin, but no precipitate was formed.

It is therefore to the pretty confiderable quantity of gallic
acid contained in the feeds of the myrica, that the virtue of
its extraét in checking dyfentaries ought to be afcribed. In
this refpeét, I am of opinion that the leaves aad bark of the
tree would furnifh an extract ftill more aftringent than the
berries.

The following are the moft interefting refults of an exami-
nation of the wax:

When extraéted either by decoétion from the feeds, or by
folution of the white powder in alcohol precipitated by water,
this melted wax is always of a yellow colour, inclining to
“sap Its confiftence is ftronger than that of the wax made

y bees; it is dry and friable enough to be reduced to pow-
der; in aword, it is manifeftly more oxygenated than wax
prepared by thefe infeéts, Tapers made with the wax of the

- myrica

366 ‘Memoir on the Wax-Tree

- Myrica give a white flame and a beautiful light, without
fmoke, do not run, and when new emit a balfamic odour
which the inhabitants of Louifiana confider as very benefi-
cial to the fick: when diftiiled im a retort, it pafies in a
great part to the ftate of butter. This portion 1s whiter than
it was before, but it lofes its confiftence, and acquires that
of tallew. Another portion is decompofed, furnifhes a lit-
tle water, febacic acid, and empyreumaticoil. A great deal
of carbonated hydrogen gas and carbonic acid gas are difen-
gaged, and there remains in the retort a black carbonaceous
bitunien. Common wax whien diftilled, exhibits the fame
phenomena. ;

I have already faid that alcohol diffolves the wax of the
myrica, but ether diffolves it much better, and, by the eva-
poration of the liquid, it feparates im the form of {talagmites.
Neither of thefe hquids defiroy its colour. If this wax be
boiled with dilute fulphuric acid, it becomes a little whiter,
but thereis no fenfible combination of the acid with it. The
yellow wax of bees, treated in the fame manner, did not
change its colour.

Oxygenated muriatic acid bleaches both kinds of wax per-
fe&tly. The vegetable wax, however, lofes its colour with
more difficulty.

The vegetable wax diffolves in ammonia. The folution
affumes a brown colour: a part of the wax becomes fapona-
ceous. The volatile alkali bas much lefs action on the wax
of bees.

Thefe two kinds of wax, when ftrongly agitated in a boil-
ing folution of cauflic potafh, wafh and form a real foap,
as obferved by Kalm the traveller. The whitenefs which
wax acquires by this faponification is not a new phenome-
non. C. Chaptal, in his procefs for bleaching by the fteam
of alkaline lees, has proved that the colouring principle of
vegetables yields to the action of alkalies. Some chemifis
afcribe this effect to the direét combination of foda or potath
with the coloured extractive part, and a combination which
brings it toa {tate almoft faponaceous and renders it foluble.

According to my opinion, the alkali, in this operation,
exercifes over the oil or wax a double attraétion, firft direé&t -
with the conftituent principles of the oil, then predifpofing
and favouring the combination of the oxygen of the atmo-
{phere with oi] or wax. | do not know whether auy one be-
fore me ever entertained this idea; but it was fuggetled by
obferving what takes place when foap is decompofed by an
acid.. The oil is always concrete and more oxygenated than
it was before. }

It

of Louifiana and’ Pennfyivania, 267

It would be of importance for the theory of chemiftry to
make foap, if poffible, in a clofeveflel, and to examine the
air afterwards, or in different gafes containing no oxygen.

By decompofing foap of the myrica, very white wax is
ebtained; but in a particular ftate, which does not admit of
its being employed for our purpofes.

Litharge, or femi- vitreous oxide of lead, diffolves very well
in the melted wax of Louifiana. It forms a very hard mafs,
the confiftence of which may be diminithed at pleafure by
the addition of a little oil. 1f the wax of the myrica, as there
is reafon to think, retains a portion of the aftringent prin-
ciple given by a decoétion of the berries, the phyficians,
perhaps, will find ufeful properties in topics made with this
wax, ‘

By taking a general view of what has been here faid, it is
feen that the myrica may be of very great fervice in the arts.
The wax which it furnifhes is fufficiently abundant to prove
an ample indemnification for the care and expenfe of cultiva-
tion, fince a fhrub in full bearing gives fix or feven pounds
of berries, from which a fourth of wax may be extracted.
This wax is of a quality fuperior to that of bees.

The aftringent principle of the myrica, extracted on a large
feale, may be very ufeful either in medicine or in the arts:
In certain refpects it may be fubftituted for the gall-nut in
dyeing, hat-making, and perhaps in the tanning fome kinds
of leather. The colouring principle feems to be fufficiently
fixed to deferve fome attention; and, if it be true that in
Louifiana beautiful Jakes are made from it, why is it not
rendered ufeful in painting ?

In a word, when this wax becomes fufficiently common to
be fold at a Jow price, great advantage might be derived from
it in making foap.

The art of bleaching this wax requires alfo fome refearches,
when it is to be performed on a large feale with economy.
Two re-agents prelent themfelves to manufacturers—the ful-
phuric acid and the oxygenated muriatic. But as wax does
not fink in thefe liquids, means muft be found to multiply
the contact, either by cutting the wax into flices and be-
fprinkling it with oxygenated mariatic acid, or fhutting it up
when. cut in this manner, in catks, into which oxygenated
muriatic acid is introduced. j

I (hall propofe a third method, which feems to promife a
fpeedier effect. Place the wax, cut into {mall pieces, in al-
ternate firata with hyper-oxygenated muriate of lime: when
arranged in this manner, leave it for fome time dry and in con-
taét, The falt and acidulous water are then to be decompofed o

the

268 Memoir on the Wax-Tree

the fulphurie acid, taking care to pour in water gradually, at
different periods, till there is»no longer a fenfible difengage-
ment of muriatic gas. A large quantity of water is then to
be added, and. the mixture mutt be ftirred with a rod.. By
reft, the infoluble fulphate of lime is precipitated, and the
bleached wax will float at the furface.

I fhall terminate this memoir with fome obfervations on
the culture of the myrica.

C.Defhayes, to whom I am indebted for the trials I
made, has obferved, for feveral years, the wax-trees of Ram-
= What he wrote to me on this fubjeét is as fol-

ows:

“© The Myrica latifolia (Ayton) is here abfolutely in its
native country: it is in the foil proper for it; that is to fay,
in fandy and blackifh turf. We have fixteen wax-trees in
full vigour. They are four, five, and fix feet in height: one
male is feven feet. The feeds are abundant almoft every year:
I fay almoft, becaufe in fome years they fail. The fruit in
general is in that part of the Englith garden affigned to it.

“* The culture requires no care. Every year a great num-
ber of fhoots, which proceed from the roots of the large trees,
are pulled up. Thefe are fo many new fhrubs, which are
then planted at the diftance of a yard from each other.

“¢ The feeds may be fown in beds in the fpring, and then
tranfplanted: but this method is tedious. The myrica will
fucceed wherever it finds a light foil, fomewhat moift. How
many provinces are there where the cultivation of this fhrub
would be ufeful, and employ land almoft neglected !

** What advantages may not agriculture hope for from fuch
an acquifition, fince Pruffia has fo long feen the myrica
flourith in its dry, fandy plains !”

C. Thiebault, of the Academy of Berlin, gave me the fol-
_ Jowing interefting note on this fubjeét :

«* The Jate M. Splzer, author of a general dictionary of the
fine arts, had obtained from Frederic the Great a pretty ex-
tenfive piece of wafte land on the banks of the Spree, at the
diftance of half a league from Berlin, in a place called the
Moabites. However barren this ground, which prefented
only a very thin, poor turf, above fine light fand, might be,
M. Sulzer converted it into a very agreeable garden, worthy
of a philofopher. Among other remarkable things he formed
a plantation of foreign trees, confifting of five pretty long
alleys ening eaft and weft. In thefe alleys there were not
two trees of the fame kind following each other. In the al-
leys moft expofed to the north he planted none but the highett
trees, capable of with{landing the feverity of the climate.
Hence,

of Louifiana and Pennfylvania. 269

Hence, in proceeding from the north to the fouth, the firft
alley exhibited trees of about feventy feet in height, the
fecond trees of from twenty-five to thirty, and fo on, in the
form of an ampbitheatre; fo that all thefe trees had the fun
at leaft in part, and the weaker were fheltered by the fironger,

* In the moft fouthern alley I obferved a fort of fhrub
which rofe only to the height of two or three feet, and which
M. Sulzer called the wax-tree. Every perfon vifited this
alley in preference to the reft, on account of the delicious
perfume emitted by the leaves, whieh they retained a very
long time.

C. Thiebault then fpeaks of the method of extra&ing
the wax. This operation is the fame as that defcribed by
M. Alexandre.

_“ T have feen,”’ adds he, “ one taper of this wax perfume
three chambers which compofed M. Sulzer’s private apart-
ments, not only during the time it was lighted, but even for
the reft of the evening.”

The myrica cultivated at Berlin was, no doubt, more odo-
riferous than that which we poflefs, the wax of which does
not emit the fame perfume.

M. Sulzer intended to make tapers of this wax not

bleached, covered with a coating of our fineft wax. The
heirs of this academician fold the garden, but the wax-trees
ftill remain. They were planted in 1770.
* Ifit has been found poffible to naturalize the myrica ceri-
fera in the north, why fhould we neglect a vegetable produc-
tion fo valuable, which would certainly thrive in our fouthern
departments, and which requires les care than bee-hives.
The fuccefsful trials which haye been made muf excite the
zeal of our agriculturifts,

The government bas already encouraged this branch of
induftry by ordering plantations of the wax-tree. There are
nurferies at Orleans and Rambouillet which contain more
than 400 fhrubs. Refults fo fatisfa€&tory cannot be made
too public. Ufeful plants are always propagated flowly; a
barren but picturefque tree, an agreeable fhrub, are foon
adopted through fafhion: they ornament the parterres of
our modern Luculluses and the flower-pots of our Phrynes,
while our indefatigable agriculturifis exhauft themfelves in
vain efforts to enrich our meadows with a new grafs, or ta
fill our granaries with a new nourifhing grain. The vulgat,
through prejudice, long rejected maiz and potatoes, which
have aa of fo much fervice to our foldiers and to the poor,
The oak, which fed our anceftors, is no longer found in our
fore(ts, Let us, however, hope that our agriculturilts will
; at

270 Royal Society of London.

at length open their eyes to their real imterefts; and thafy
laying afide their old prejudices, they will mot difdain the
prefents which learned focieties are defirous to give themy
and which will conduce as rich to their advantage as to the
glory and profperity of France.

XLII. Proceedings of Learned Societies:
ROYAL SOCIETY OF HONDON:

Ox the goth of November, being St. Andrew’s day, the
Royal Society held their anniverfary meeting at their apart-
ments in Somerfet-place, when the gold medal (called Sir
Godfrey Copley’s) was prefented to Wilham Hyde Wol-
lafton, M.D. for his various papers printed in the Philofo-
phical Tranfactions. Mee

Afterwards the Society proceeded to the choice of the
council and officers for the enfuing yeat, when, on examin-
ing the ballots, it appeared that the following gentlemen were
elected of the council :

Of the old council—The right hon. fir Jofeph Banks, bart.
K.B.; fir Charles Blagden, knt.; Henry Cavendith, efq. ;
Edward Whitaker Gray, M.D.; right hon: Charles Gre-
ville; right hon. fir William Hamilton, K.B.; Rev. Nevil
Mafkelyne, D:D.; George earl of Morton, K.T.; Jofeplx
Planta, efq.; Benjamin count Rumford; Samuel Wegg, efqe

Of the new council—Mark Beaufoy, efq.; Andrew Dou-’
glas, efq.; fir Martin Browne Folkes, bart.; Charles Hat-
chett, efq.; Everard Home, cfq.; Thomas Barnard, lord
bifhop of Limerick; William Marfden, efq.; Jofeph de
Mendoza Rios, efq.; Francis earl of Moira; William Hyde
Wollafton, M.D.

And the officers were—Sir Jofeph Banks, bart. prefident ;
William Marfden, efq. treafurer; Jofeph Planta, efq., Ed-
ward Whitaker Gray, M.D., fecretaries.

Afterwards the members of the Society dined together, as
ufual, at the Crown and Anchor tavern, in the Strand.

The Tranfaétions of the Society for 1802 contain the fol.
lowing papers:

1. The Croonian Le&ure. On the Power of the Eve to
adjuft itfelf to different Diftances,.when deprived of the Cryf-
talline Lens.. Ry Everard Home, Efq. F. R. S.—2. The
Bakerian Lecture. On the Theory of Light and Colours.
By Thomas Young, M.D. F. R S. Profeffor of Natural
Philofophy in the Royal Inftitution,—3. An. Analyfis of a

5 mineral

Royal Society of London. bre
thineral Sabftance from North America, containing a Met
hitherto unknown.’ \ By Charles Hatchett,: Efgi F. R. S.—
4- A Defcription. of the Anatomy of the Ornithorhynchus
paradoxus. By Everard Home, Efq. F.R. S.++5. On the
Independence of the analytical and geometrical Methods of
Inveftigation; and on the Adyantages to be derived from
their Separation. By Robert Woodhoufe, A. M. Fellow of
Caius College, Cambridge.—6. Obfervations and Experi-
ments upon oxygenized and hyper-oxygenized muriatic Acid;
and upon fome Combinations of the muriatic Acid in its
three States. By Richard Chenevix, Efq. F. R.S. and M.
R. 1. A —7. Experiments and Obfervations on certain ftony
and metalline Subftances, which at different Times are faid
to have fallen on the Earth; alfo on various Kinds of native
Tron. By Edward Howard, Efq. F. R. S.—8. Obfervations
on the two lately difcovered celeftial Bodies. By William
Herfchel, L. L.D. F. R. S.—g. Defcription of the Corun-
dum Stone, and its Varieties, commonly known by the
Names of Oriental Ruby, Sapphire, &c.; with Obfervations
on fome other mineral Subftances. By the Count de Bour-
non, F.R. S—zo.Analyfis of Corundum, and of fome of
the Subftances which accompany it; with Obfervations on
the Affinities which the Earths have been fuppofed to have
for each other, in the hamid Way. By Richard Chenevix,
Efq. F.R. S. and M. R. I. A.—11. Defcription of the Ana-
tomy of the Ornithorhynchus Hyftrix. By Everard Home,
Efq. F. R. S.—12. A Method of examining refractive and
difperfive Powers, by prifmatic RefleStion. By William
Hyde Wollafton, M.D. F. R. $.—13. On the oblique Re-
fraction ef Iceland Cryftal. By William Hyde Wollafton,
M.D. F.R.S.—1q4. An Account of fome Cafes of the Pro-
duétion of Colours, not hitherto defcribed. By Thomas
Young, M.D. F.R.S. F.L.S. Profeffor of Natural Philo-
fophy in the Royal Inftitution.—15. On the Compofition of
Emery. By Smithfon Tennant, Efq.F. R.S.—16. Quelques
Remarques fur la Chaleur, et fur l’Aétion des Corps qui
Vinterceptent. Par P. Prevoft, Profeffeur de Philofophie a
Genéve, &c.—17. Of the Reétification of the Conic Sec-
tions, By the Rey. Jobn Hellins, B.D. F.R.S. and Vicar
of Potter’s Pury, in Northamptonfhire.—18. Catalogue of
500 new Nebula, nebulous Stars, planetary Nebula, and
Clufters of Stars; with Remarks on the Conftruétion of the
Heavens. By William Herfchel, LL.D. F. R. S.

APPENDIX.—Meteorological Journal kept at the Apart-
—_ - the Royal Society, by Order of the Prefident and
uncil,

FRENCH

272 French National Inflitute :

FRENCH NATIONAL INSTITUTE.

Proceedings during the laft quarter of the year 10, conti-
nued from our laf{ Number.

NATURAL PHILOSOPHY.
Of Meteors fuppofed to fall under the form of Stones.

A great deal has been faid of ftones which have fallen
from the clouds; it was long believed that this was one
-of the forms affumed by thunder in its fall; they were then
confidered as the produét of the explofion of certain lumi-
nous balls, which are fometimes obferved. The rarety of
thefe phenomena, however, which has not allowed of their
being feen ata fhort diftance by obfervers poffeffed of intel-
ligence, and at the fame time worthy of credit, and which
feems hitherto to have referved them for the eyes of the vul-
gar, fo much inclined to exaggeration, has prevented the
Jearned from believing in the exiftence of thefe ftones.

However, moft mineralogical colleétions, contain a great
number of ftones, to which this origin has been afcribed.
They exhibit exterior uniform characters : a fpecific gravity
nearly equal, and by analyfis, give the fame component parts,
among which is nickel, a fubftance rarely found at the fur-
face of the earth ; and iron ina metallic ftate, which is ne-
ver met with in volcanic productions, to which thefe ftones
in other refpects feem to be very analogous.

Thefe remarks have induced Mr. Howard, and Count de
Bournon, to think that, however doubtful the fall of ftones
from the atmofpheric regions may be, it ought to be fubjected
to accurate examination. They have collected the different
teftimonies in a paper read before the Royal Society of London,
and C, Pictet thought it proper to prefent it to the clafs, that
the attention of philofophers may be direéted to this fubje&,
in order that the phenomenon, if true, may be confirmed ;
or, if only an illufion fupported by popular error, may be
confined for ever to the clafs of errors.

CHEMISTRY.
On the Pruffiates of Barytes and Lime.

After the bafes of a theory have been eftablifhed on im-
portant facts well confirmed, and when by a methodical ar-
rangement of the feience they have been diftributed, as we
may fay, into regions, the communications between which

are known, it remains to review them in detail, in order that
all

On Mercurial Salis: 273

all the parts may be carefully deferibed, and that thefe parts
may be affigned to the regions which they compofe. Such,
it appears is the idea which may be formed of the prefent
ftate of the chemical knowledge of falts; Their general for-
mation feems to be well known, the great divifions are well
eftablifhed, and the principat facts have been exactly obferv-
ed and clafled ; but notwithftanding thefe fatisfaétory labours,
many details are ftill unknown or imperfect: Hence thé
refearches of the chemifts of the inftitute during this qtiarter
have been particularly dirested towards this objeét, and it
will be feen that they have not been fruitlefs.

The liquor charged with the colouring matter of Pruffiari
blue, having manifefted the property of taking metals from
their folvents, without producing a decompofition of the falts
with an alkaline or earthy bafe, the phenomenon of the pre=
cipitation of barytes had been confidered as an indication
of the metallic nature of that fubftance, which could not be
reduced to a metallic ftate, becaufe it had a greater affinity
for oxygen than carbon. The moft celebrated chemifts had
adopted this opinion, others had announced that precipita-
tion did not take place. Mr. William Henry thus main-
taining that pruffiates perfectly bin did not produce any
oe; confirmed himfelf the firft obfervations of
3ergman and Lavoifier, and announced that there was formed
by double affinity a real pruffiate of barytes: C. Guyton,
having long obferved that pruffiate of lime was decompofed
hy carbonate of potafh, made ufe of this experiment, and
thofe of Mr. Henry, to fix the theory of thefe phztiomena ;
and, inftead of concluding, like the Englifh chemift, that ba-
rytes differs in this refpeét from other earths, and approaches
the nature of metals, he fhows that the fame effect takes
place with lime, ftrontian, magnefia, potafh, foda; and
even ammonia, and confequently that, in all thefe cafes,
there is nothing but the neceffary refult of the concurrence of
feveral divellent forces.

On Mercurial Salis.

After treating different oxides of miercury, as already meti-
tioned in his memoir, C. Fourcroy continued to read an ac-
count of bis labour during the laft quarter; In this fecond
part he employed himfelf on the fulphates and nitrates of
mercury 5 a very complex kind of compounds, exceedingly
variable, the charaéters and properties of which have been
examined by many chemifts, without their being able to de-
termine the real differences between them, and particularly
the caufe of thefe differences, The author had already made

Vou, XLV. No. 55. S this

a4. French National Inflitute :

this kind of combination the fubjec& of his refearches, and in
179! communicated to the academy of fciences a pretty
long paper on thefe falts. He eftablifhed three kinds of
them, diftinguifhed by the proportions of acid and oxide,
and he fhowed a difference between them, founded on the
different ftates of oxidation of the metal.

Different fulphates are made not only by expofing mercury
with fulphuric acid to a greater or lefs heat, and for a longer
or fhorter time, but alfo by mixing this acid ora foluble ful-
phate with a nitric folution of mercury, more or lefs oxi-
dated. If the latter is little oxidated, a white precipitate of
fulphate little oxidated is obtained ; if it be much oxidated
a yellow precipitate highly oxidated will be obtained ; ful-
phuric acid united to two or three parts of water does not
form fulphate of mercury much oxidated, unlefs it be con-
centrated by long and ftrong ebullition; without this, the
water added for wafhing does not render the mixture yellow,
and will not make turbith mineral. The author gives the
proportions of the component parts, acid, oxygen and mer-
cury, of the different neutral or acid fulphates, little or very

much oxidated. Thefe refults are a fupplement to his labour:

of 1791 on this kind of mercurial falts.

Nitrates of mercury furnifhed him with obfervations ftill
newer and more important for fcience than the fulphates.
There are two kinds of nitrates, one much oxidated, and the
other little oxidated. The formeris precipitated, of a gray
colour, and almoft black by alkalies, and white by fulphates ;
with muriatic acid it forms mercurius dulcis. The nitrate
much oxidated, refults from long and firong ebullition, gives
no precipitate by muriatic acid, it gives a yellow one with ful-
phates, a white one with ammonia, and an orange yellow one
with fixed alkalies. Nitric folutions of mercury, are often

mixtures of the two falts. That which precipitates by water

is a folution of oxide much oxidated, or red, in concentra-
ted acid. When a nitric folution of mercury, little oxidated,
is precipitated by a fixed alkali, the firft portion of the white
precipitate, a little coloured, which is obtained, is a nitrate of
mercury infoluble and neutral,’ formed by the union of the
feparated portion of oxide with the remainder of the folution
which is not decompofed. What is new in this Jabour
is, the comparifon of the properties of the nitrite of mercury
with thofe of the nitrate. Almoft all folutions contain more
or lefs of the former of thefe falts. It is prepared by making
nitrous gas pafs into nitric folutions, which greedily abforb
it. Super-oxidated nitrate abforbs much more of it than

the nitrate little oxidated, The latter, nitrite of mer-.

cury,

On Aluminous Sulphates.—New Triple Salt. 275

eury, difengages a great deal of rutilating vapour by the ful-
phuric and nitric acids, It tinges the fkin of a dark purple
colour: while nitrate very much oxidated dyes it black, and
‘ nitrate little oxidated, like the nitrite of the fame nature, does
not change the colour of animal matters. It retains longer
in the open air its nature of nitrite than the alkaline nitrites,
which fpeedily refume the nature of nitrates. Alkaline ni-
trites, and particularly deliquefcent nitrites, may be prepared
without difficulty by impregnating the folutions of nitrates,
&c. with nitrous gas, which eafily condenfes in them.

The author, to terminate his Jabour, is to occupy himfelf
with the muriates of mercury, of which he has difcovered a
new kind, and with the fulphurets of the fame metal. It
would be a pity that the important and numerous functions
entrufted to him, fhould oblige him to difcontinue thefe ufe-
ful refearches; but, happily for the intereft of fcience; people
oe abandon acareer which they have long purfued with

uccefs,

On Aluminous Sulphates.

S. Seguin, having been employed in continued refearches
on the different ftates of the fulphates of alumine, read on
that fubje& a memoir, in which he proves That the acid
fulphate of alumine pure, that is to fay when free from thofe
fubfiances which it is neceffary to add to it in order to make
it cryftallize, does not, in any cafe, decompofe the muriate
of foda—That alum, the caufe of the cryftallization of
which is the fulphate of potath, does not experience decom~
pofition from the muriate—That alum, the caufe of the
cryftallization of which is the fulphate of ammonia, receives
no alteration from the muriate of foda, when it contains only
ay quantity of fulphate of ammonia indifpenfably neceflary
or its cryftallization—Finally, that alum, containing more
fulphate of ammonia than the quantity neceflary for its cryf-
tallization, is the only falt which experiences alteration by
the muriate of foda; and that this alteration is confined
merely to the decompofition of the fulphate of ammonia
which it contains in excefs.

A New Triple Salt.

There refults from the decompofition above mentioned, on
the one hand muriate of ammonia, and, on the other, a
triple falt, compofed of fulphuric acid, foda and ammonia,
aud which had not been Plots remarked. Pi yAbs

A mixture either of the fulphate of ammonia and muriate
of foda, or of fulphate of foda and fulphate of ammonia,

S 4 produces

246 French National Inftitute :

produces this triple falt in its full purity. In the firft of
thele two cafes, the aflinity of the fulphate of ammonia fot
the fulphate of foda oppofes the total and generally admit-
ted decompofition of the fulphate of ammonia by the muriate
of foda. ‘This triple falt acts a diftinguifhed part in the fa-
brication of fal ammoniac: it cryftallizes regularly ; does not
efflorefce in the air; has a favour, at firft pungent, then
flightly bitter ;.is decompofed by foda, which transforms it
wholly into fulphate of foda; decrepitates in the fire, {wells
upin it, and fuffers to: be difengaged, firft ammonia, and
then acid fulphate of ammonia, while pure fulphate of foda
remains at the bottom of the veffel.

A New Polifbing Rouge.

Chemiftry, which can contribute in fo effe@ual a manner
to the improvement of the arts, does not lofe this important
direction, and, in this refpeét, defcends to the minuteft de-
tails. In confequence of a report prefented to the Clafs, on
a rouge for polifhing, C. Guyton communicated fome ob-
feryations on ochry reds fimilar to thofe of Almagra in Spain,
and which, in many cafes, might be fubftituted for red
oxide of iron-or colcothar. Tie mentioned as a very ceco-
nomical procefs, and proper for giving the laft polith to the
hardeft matters, the ufe of bits of old hat, which, as is well
known, are dyed with iron. By immerfing thefe pieces of
hat for fome minutes in fulphuric acid, the iron which’ they
contain pafles to the ftate of red oxide, and they then be-
come excellent pieces’ for polifhing, and may be ufed in the
fiead of thefinett rouge,

i
Analyfis of an Ore of Uranium.

€. Sage communicated to the Clafs the ‘analy fis ‘he made
of a fulphurous ore of uranium, of a blackith brown coloat,’
without a regular form, \and brought-from. Erbenfloch in’
Saxony. } (bil). o1
This ore, which has fome external relation to that gene-
rally known under the name of pechblende, is) however
diflerent in its colour, which is brownifh and dull, and in
exhibiting fome pyritous points. . It contains iron,’ the pre=
fence of which was manifefted by the magnet, after the tor-
rification neceflary to difengage the fulphur.
it refults from the different trials to ‘which this fubftance
was fubjected by C. Sage, that 100 parts of it contain 78 of
uranium, 20 of iron, and 2 of fulphur.
‘Thinking, like all thofe who poffefs any elevation of
mind, and a philofophical fpirit in cultivating the foiehstes
that

Sulphurous Ore of Uranium.— Anatomy. 27%

that itis more proper to confecrate the names of men who
have enriched them by their difcoveries, than thofe of the fa-
bulous deities, and great men who refemble thefe deities in a
great many points, C, Sage wifhed that the name of uranium
given to this metal by the Germans, who call the planet dif-
covered by Herfchel Uranus, might be changed. In ap-
plauding thefe motives, it will perhaps be found that the
names of celebrated men ought to be affigned to thofe things
which have been the particular objects of their attention,
and that Klaproth, who difcovered this metal, has a greater
right than any other to diftinguifh it by his name. The
French feem conftantly to agree in giving the name of
Herfchel to the planet which he brought from that obfcurity
under which it had been concealed for fo many ages; and,
by the effe& of the fame fentiment of juftice, the names of
Piazzi and Olbers will undoubtedly remain to thofe dilco-
vered by thefe aftronomers.

Zoologifts and botanifts now confecrate to their matters
and friends the genera or fpecies which they difcover; and
mineralogifts no doubt will foon follow their example. The
name of Scheele, fo juftly celebrated, has already been fubtti-
tuted for that of tung /len.

ANATOMY.
Artificial Preparations in Wax.

The art of imitating anatomical preparations with wax, of
little ufe when applied to objets eafy to be obtained by dif-
fection, and which may be daily procured, fuch as thofe of
the moft vifible parts of the human body, becomes import-
ant when baste to the reprefentation of things rare or diffi-
cult to be obtained, fuch as the different objects of compa-
rative anatomy, or of things accidental and tranfient, as
monttrofities and uncommon difeafes. In the laft place, it
is almoft indifpenfable to make known to pupils certain parts
of fuch a complex nature, that the demonttrator cannot de-
velop the whole in one diffeétion.

It is to this laft clafs that we muft refer the lymphatic
veffels. The fuccefs of inje&ting them is fo variable; the
quickfilver employed for that purpofe is fo inconvenient, in
confequence of the fluidity it retains; in a word, it is fo rare
that it can be made to penetrate to the laft ramifications of
thefe veflels, even in one limb, that it is only by repeating
thefe operations for a long time, and on a great number of
fubjects, that it has been poffible to become acquainted with
the whole of this vafcular fyftem. Natural pieces, prepared

S 3 with

28 French National Inflitute.

with the greateft care and fuccefs, foon alter, becaufe the
mercury abandons their upper parts to accumulate itfelf in
the lower, the veflfels of which it dilates and ruptures.
Young anatomifts then cannot, without the afliftance of the
arts of imitation, acquire elementary notions on this objet.
The cafe is the fame in regard to preparations of the nervous
fyftem, though lefs difficult to be made from bodies, but
which, by deficcation, are foon rendered indiftinét, and al-
moft ufelefs.

It has long been found that anatomical preparations, exe-
cuted in wax, are thofe which exhibit, in the cleareft man-
ner, the qualities of fuch objects, namely, all their dimen-
fions and all their colours; while other imitations, fuch as
commion feulpture, engraving, and even painting, befides
that they are not of a nature fo delicate as thofe, of wax,
cannot exprefs, at the fame time, thefe two orders of qua-
lities. Hence this method has been exclufively preferred to
all others, and has been employed to form colleétions al-
ready celebrated. But feveral of them, while they give us
reafon to admire the hand of the artift, leave room fome-
times for regretting that it was not directed by the anato-
mift familiarifed with all the details of diffection.

The union of thefe two kinds of talents in the perfon of
C. Laumonier, affociate of the Inftitute, has given great
merit to three pieces which he fubmitted to the infpeétion of
the Clafs; namely, a lower extremity, in which he has re-
prefented the mufcles, the fuperficial veins, the extremities
of the arteries, and the lymphatic veflels; a head, exhibit-
ing the cranium open, and the brain covered on the one fide
by the dura and pia mater, and uncovered on the other,
The face and neck are prepared in fuch a manner, as to fhow
chiefly the facial nerve, the eight pair, and the cervical
branches. Another head, open at the height of the orbits,
prefents a feétion of the pofterior lobe of the brain, and 4
portion of the cerebellum, cut above its tentorium. It was
prepared with a defign to exhibit the origin of the great fym-
pathetic nerve, and more particularly the cavernous ganglion,
difcovered by the author, and defcribed with all its com-
municating branches-in the Journal de Phyfique.

Thefe pieces, executed by the order of government for the
School of Medicine, form’a continuation of others which
have been depofited there for fome years, and which are not
inferior in point of merit,

4

MEDICINE.

French National Inflitute. 279

MEDICINE.

Chemical and Medical Experiments on the Diabetes Mellitus.

Life, that phyfical, mechanical, and chemical procefs, fo
complex, exhibits in its aberrations, as in its perfect accom-
plithment, phenomena which are as much interefting to the
philofopher as the phyfician. It is under this double point
of view that C. Nicolas, affociate member of the Inftitute,
and profeftor of chemiftry in the central fchool of Calvados,
and Dr. Guedeville, have confidered the diabetes mellitus, OF
the pthy/uria faccharina.

The prefence of the faccharine matter, which, for a long
time, was found only in the fugar cane (Arundo faccharifera,
Linn.), bas, by the labours of modern chemifts, been dif-
covered not only in many other vegetable fubfiances, fuch as
the mallow, the juice of the maple, beet-root, &c. bat alfo
in the mineral kingdom, where C. Vauquelin has proved its
exiftence by his analyfis of the emerald and aigue-marine.
Some produgs of the analyfis of milk had fhown an ana-
logy between it and fugar. Dr. Willis remarked, that, in
the morbid affection in queftion, the firft fymptom of which
is a fuperabundant evacuation of urine, this fluid aflumed a
fweet faccharine quality, inftead of the acrid and pungent
favour which it has in general.

C. Nicolas and Dr. Guedeville, in the courfe of their
practice, having met with patients attacked by diabetes, ur-
dertook a comparative analyfis of the urine voided in the dia-
betic ftate and in that of health. They afcertained, by care-
ful experiments, the exiftence ‘of the mucous faccharine
matter in the former: they extracted from it acetous acid
and alcohol, while in the fecond it is not fufceptible of fer-
mentation, either vinous or acid.

The memoir of C. Nicolas and Dr Guedeville, which

may be confidered as a complete treatife on the diabetes mel-
litus, eontains a hiftory of the catifes afcribed to this difeafe,
and the means employed to combat it fince the days of ret
pocrates to the prefent time; and an exact defcription of the
Sarge it exhibits at its different ftages; the principal re-
ults of their important labour on this difeafe, obfervations
of which would be lefs rare were it not for the negligence of
many phyficians, who commit into the har.ds of quacks and
urine doélors the unfortunate patients attacked by it.

The principal caufe of the diabetes mellitus, which feems
to be moft frequent in countries where cyder, or liquors of

.

that kind, is drunk, is a fpafmodic and continual tie
$4 °

289 French National Infhitute :

of the unanimalized nutritive juices to the urinary organ,
which alters alfo the gaftric, pancreatic, biliary, &c. juices.
It feems to be peculiar to mufcular temperaments. Its feat
is placed in the fyftem of digeftion; and the urinary organ,
by the excefs of its evacuations, fupplies the want of other
excretions and fecretions which are fufpended.

The urine which paffes, as already faid, has the vinous
and acctous fermentation, gives alcohol of a difagreeable
odour, a cryftallized fugar, the nature of which is not yet
well known, inftead of wrée, uric and benzoic acid, which
it ought to contain. Ammoniacal and phofphoric falts fhow
themfelves in it only in very fmall quantity; the blood of
phtyfuric patients is exceedingly ferous, and contains feareely
any ammoniacal and phofphoric falts. Thefe phenomena
furnifh the following indications :—

ift. To remove the fpafmodic ftate. ?

2d. To reftore to the nutritiye juices the principles of ani-
malization. ;

And, to accomplifh thefe ends, to fele&t the food and re-
ee from fub{tances which contain azot and phofphoric
alts..

From thefe indications C. Nicolas and Dr. Guedeville
have prefcribed to the fubjeéts of their different obfervations,
an animal regimen, compofed of fat meat and milky beve-
rages, in which phofphate of foda is diffolved. As medi-
cines, they employed boles formed with an ‘aqueous extract
ef opium and cinchona; fometimes alfo mufk. This treat»
ment was attended with complete fuccefs *.

GEOLOGY.
Obfervations made on the Summit of Mont-Perdu.

The beauty of fites exhibited by mountains, and in partis
cular the hope of reading on thofe awful maffes the hiftory
of the revolutions which they feem to have witneffed, or at
Jeaft of their refults, continually attraé&t towards their fum-
mits thofe who have once experienced the charm of thefe
meditations, which might be called antediluvian.

C. Ramond, whofe particular ftudy it has been to make us
acquainted with the Pyreneés, and particularly Mont-Perdu,
has confirmed by a new tour, that this mountain oyerlaoks
all the furrounding peaks,

* Thofe who have feen Dr, Rollo’s and Mr. Cruickfhank’s valuable
works on the Diabetes Mellitus, will be not a little furprifed to find them
not even quoted in the preceding notice, though they prefent every one of
the facts that have been noticed in it as new! EpitT,

The

Obfervations made on the Summit of Mont-Perdu. 28

~ The ridge of it confifts of beds of black marble, filled with
filiceous nodes, which here and there contain heaps of thells,
the fummit feems to have none of them, but they are found
a little further down. Thefe beds or banks, which are ge-
nerally parallel, follow the principle direction of the chain,
and are fubjeét to fexions more or lefs confiderable on each
fide of this diretion. They are almoft all vertical, their
mean inclination being about 80° to the fouth.

The cap of fnow which covers the peak is only about fix
feet in thicknefs, becaufe the fteepnefs of the lateral decli-
vities does not admit of its accumulation ; but, in parts where
the ground is leis fteep, the thicknefs of the {now is 40 or 50
feet, and it is more confiderable in the valleys, which catch
the fnow as it rolls down from the furrounding declivities.

The fummit of Mont-Perdu prefented to C. Ramond two
plants of the phanerogamia kind, the Aretia alpina, Linn.,
and the Saxifraga retufas, Gorian. Lower down he found
the Ceraftinum alpinum, the Saxifraga grenlandica, and the
Ranunculus pamaffifolius. He is of opinion that it is not the
height of the peak, but the want of earth proper for vegeta-
tion, that renders plants fo rare on the fummit. He faw
fearcely any thing but a few remains blafted by lightning and
buffeted by the winds; and if, amid{t this deftruction, occa-
fioned by the combined action of the moft powerful meteors,
a rock ftill in its place offered vegetables a firm fupport, it
was covered by turf and plants in fuch a ftate of vigour, as
proves that it is neither the want of air, nor the lownefs of
temperature, that banifhes them from thefe regions.

The revolutions which this part of the globe has experi-
enced appeared evidently to C. Ramond, to have been oc~
cafioned by the rending of the primitive mafs, the falient and
re-entering angles of which are {till fo entire and fo tharp,
that he thinks if the caufe which disjoined them fhould ope-
rate exactly ina contrary direction, they would unite in fuch
a manner, that the joining would be imperceptible.

Thefe characters, peculiar to the mafs of Mont-Perdu, ‘‘make
it, fays Ramond, like an ifland of a few leagues in extent,
raifed by fome reyolution on the back of the Pyreneés.”

GALVANIC SOCIETY, PARIS.

Dr. Nauche, prefident of the fociety, with the fenators
Aboville and Lefpinaffe, has made’ a curious obfervation,
which is of fome importance on account of the inferences
that may be deduced from it. He has found that it is pof-
fible to make a blind perfon, however great the degree of
blindnefs, to perccive very lively and numerous flathes of

5) light,

282 Galvanic Society, Paris.

light, by bringing one extremity of the voltaic pile nto com-
munication with the hand or the foot, and the other with the
face, the fkin, of the head covered with hair, and even the
neck. There exifts a line of demarcation, beyond which no
flafhes take place.

Dr. Nauche has alfo confirmed with his fellow labourers,
Tourlet. Legallois, Bonnet, Douffin-Dubreuil and Pajot-
Laforét ;

1ft, That reiterated applications of galvanifm, when they
comprehend the half of the trunk, produce in the _perfon
{ubjected to them great agitation, many reveries, involuntary
tears, increafed fecretion of faliva, an acid or alkaline tafte, a
great fecretion of urine, an increafe of heat and tranfpiration,
abundant fweat in the galvanized parts, great difturbance in
the ftate of the pulfe, which is accelerated, and often imper-
ceptible at the moment of the commotions.

ad. That the aétion of the galvanic fluid may be increafed
by drawing it off by a fharp point, which does not appear to
act at the moment of contact.

He has been able alfo to ftimulate the organs feparately,
by direéting to the nervous trunks, which diftribute them-
felves to thefe organs, or which communicate with them, the
two extremities of the pile, of the circle of cups or of the gal~
vanic trough. Heremarked that, by making the application
a bath charged witha faline folution, a ftrong galvanic bath
may be obtained, the effects of which are mild, and fome-
times more adyantageons than thofe obtained by other pro-
ceffes.

p Paris, Dec. y7th.

Tn the laft fitting of the Galvanic fociety, M. Robertfon
repeated experiments on the combuttion of phofphorus and
metals, by means of a very large pile compofed of plates of
copper and zinc. M. Gantherot announced that platina is
a worfe conductor of the galvanic fluid thaniron. Medical
applications were not negledted, and among’ the ufeful
refults the following were mentioned: The cure of a gutta
ferena, with which a domeftic of M. Gillet-Laumont, mem-
ber of the council of the mines, had been affeéted, by M.
Nauche, the prefident: of a fciatica, on the coachman of the
fecond, by M. Dudanjeon; and of a palfy in the right arm,
by M. Pajot-Laforét. The fociety appointed M. Laplace,
Aboville, Lefpinaffe, Suc, Dubreuil, Paroiffe and Judelot,
to make experiments at the national eftablifiment of the
Quinze-Vingts on perfons born blind.

THE

Prize Queffions. 283

THE BATAVIAN SOCIETY OF THE SCIENCES AT
ROTTERDAM.

On the 21f of Auguft, the fociety propofed the following
new prize queftions,

it. What are the phenomena obferved in regard to
the origin and progrefs of waves, in laying the foundations
of piers, at greater or lefs diftances? What means have
from time to time been difcoyered, and tried with more or
lefs advantage to reftrain or to leffen the deftructive confe-
quences of the courfe of the wayes? What can be deduced
from thefe phenomena, for explaining the caufe of waves;
and what ufe can be made of this knowledge, to improve the
means already adopted for fubduing the waves, or to render
them more powerful ?—To be anfwered before the 1f of
March, 1804.

od. What is the reafon that the experiments in regard
to the conducting power of bodies for caloric, are fo uncer-
tain and often contradiétory? and what is the fureft and
propereft method to afcertain the quantity of this conducting
power both in folid and fluid bodies ?—To be anfwered be-
fore the ft of March, 1803.

The prize for each quettion is a gold medal of the value
of 30 ducats. The papers mutt be tranfmitted, poft paid,
under the ufual conditions, to the direétor and firft fecretary
of the fociety, Oliver Chriftian Eickma.

THE JABLOWNSKY. SOCIETY OF THE SCIENCES AT
LEIPSIC. :

This fociety has propofed the following prize queftions for
the year 1803. f

Hiflory—An account of the connection which fubfifted
between the kingdom of Poland and) the. rand. Duchy of
Lithuania, before and after the union eftablifhed by the
affembly of the States at Lublin in 1569-

Natural Philofophy.—Hittorical account of the theory of
attraction, and. the application made of it from the time of
Newton to that of Laplace.

Economy.—WV hat foreign trees and fhrubs, ufeful on ac-
count of their fpeedy growth, their duration, and their fitnefs
for fire-wood ; or applicable to the purpofes of dyeing, tan-
ning, or making furniture, can be cultivated and natural-
ized in the German pleafure-grounds?

The prize for each willbe a gold medal of the value of
24 ducats; and the papers mutt be tranfmitted, under the
ufual conditions, to profeflor Wieland at Leipfic, before the
end.of February, 1803.

r ELECTORAL

284 Eleforal Academy of Mentz, $c.
ELECTORAL ACADEMY OF MENTZ.

This fociety have pyblifhed a new volume of their tranf-
actions, 1799-1802, large oftavo, with plates. The con-
tents are, i{t. Chemical examination of fome. foflils, by
Tromfdorff. 2d, Experiments on a proper method of prepar-
ing cinnabar in the dry way, by Buchenholzen. 3d. A view
of the principles of the Derivation Calculus of the two French
analyfts, Lagrange and Arbogart, with a comparifon be-
tween it and the Differential Calculus. 4th and 5th. Ho-
meyer’s eflay, which obtained the academical prize. 6th.
Obfervation on fome rare kinds of fern, with three plates by
Wildenow. 7th. On the A/plenium, and fome plants of
the fame family, by Bernhardi. 8th. Obfervations on ftrip-
ping off the bark of fruit trees as the means of increafing
their produce. gth. On the action of common faltpetre
and common falt ‘on animal bodies, by Thilow. roth. Ex-
amination of the origin of harmony, and its progreffive for-
mration, with three plates. rrth. Stuffo, no deity of the

Thuringians, by Wolf, 12th. Eloge of M. A. H. Frank, by

Bellerman.
ROYAL ACADEMY OF-SCIENCES AT BERLIN.

The following papers have been read before the Society
fince the commencement of the prefent year :—

‘Jan. 7. A continued account of the new planets, by pro=
feffor Bode. 14. On the noble pride of men of letters, by
the director de Caftillon. 21. A paper on the queftion, To
what extent were*the antients acquainted with the art of
painting? by counfellor Hirt. 28. A public -fitting, M.
Mertan read the eloge of Mr. Selle; M. Teller, the eloge:
of M. von Wollner; profeffor Bode, a hiftory of the difco-
very of the new planets; profeffor Klaproth, an examina-
tion of the laft experiments on galvanifim.

Feb. 4. A chemical examination of the calculi found in
the ftomachs of horfes. 11. On the certainty of the mathe-
matical feiences, by profeflor Burja. 18th. A continuation
of moral and philofophical thoughts, by M. Ancillon. 25.
On the means of promoting mental culture in the ci-devant
Poland, by M. Gedike.

March 4. A fuccin& account of the manner in which the
vaccine has been introduced, brought into repute, and pro-
pagated at Vienna, by Dr. De Carena; read by M. Wal-
ter, junior. 11. Obfervations on the developement of the
funétions which contain multiple fines and co-fines of
arcs. 18. On the oldeft evidences of geology and phyfivlogy,
and particularly men; by M. Trembley. .25.:On fome
words of number, and their etymology; by M, Battide. 5;

April

J ee Oe

Medicine, 285

April 1. Some obfervations on the cow-pock ;.by Dr.
fufeland.” 8. On fome elementary theorems of philofophy 5
oh M. Grufon. 29. On the influence of the will; by M,

ein.

May 6. On the genealogy of the houfe of Proffia, 4th
period; by M. Verdy. 13. An examination of the queftion,
What is manuring? by M. Hermbftadt,. 20. Experiments
towards afcertaining the nature of fome. vegetable alkalies ;
by M. Bernoulli. 17. On improying the regulations in re-
gard to criminals; by M. Zollner. 24. On the art of drefi-
ing; by count de Guyon.

July 1. A fecond memoir on artificial meadows; by M.
Baftide. 8. Aftronomical intelligence; by profeffor Bode.
15. Refle&tions and general principles in regard to mannfac-
tures and exclufive privileges; by M. de Caftillon. 22. On
fynonyms, and the richnefs and elegance of languages; by
the abbé Denina. 24. On the black gum of the elm-tree;
by profeflor Klaproth.

Aug. 5. A public fitting. The eloge of M. de Carmer,
and the eloge of M. de Moulines; by Dr. Merian. On the
antiquity and riches of the German language; by the abbe
Denina. On the organs of fmell in man and in animals;
by M. Walter, junior.

Sept. 16. Some remarks on the foul of man; by M.
Prevoft, of Geneva. Account of the new planet of Olbers;
by profeffor Bode, 23. A fourth memoir on hiftorical pro-
blems; ‘by M. de Chambrier. 30.. Geographical obferva-
tions on the county of Hohenftein; by M. Gerhard.

= ee eee

a

ALIII. Intelligence and M: icellaneous Articles,
MEDICINE.

V \ E copy the following article from an Edinburgh paper;
it is an extract of a letter figned Civis : . é

«« While I was at Smyrna there was a girl afflicted with
a cancer in her lips, and the gum was affected. The Eu-
repean phyficians confulted on the meafure to be taken, and
agreed that they faw no other method than to cut it out;
and the girl had already fubmitted herfelf to that decifion.
By an accident of that nature which men cannot account for,
an old Armenian came to them juft in time to prevent the
application of the knife. * Do nothing,” faid the Arme-
nian, T will cure her;’”? and when be had pledged himfelf
Mrongly, the phyficians confented. He procured a Be

velfe

286 On the Weavil in Sta Bread:—Antiquities, Be.

yeffel newly tinned in the infide (an effential circumftance},
and having poured a certain quantity of olive oil into it, he
made it boil over a fmall fire, fufficient to keep it gently agi-
tated; and fo for three times in twenty-four hours. With
this the oi! refolved itfelf to the confiftency of an ointment,
and, by conftantly rubbing the part affeted, he cured her in
fourteen days.—Nothing elfe was done.

The phyficians fappofed that the oif received its virtue from
the tin, and that it was communicated by its long boiling
oyer the fire.”

ON THE WEAVIL IN SEA BREAD.

The fatal effects of the weavil in fea bread have Jong been
feverely felt by feamen employed on long voyages: rewards
have been humanely offered by the legiflature for a cure or pre-
ventative, but hitherto without fuccefs. The following fa& was
difcovered by accident, and is now offered to the public as a
hint worthy the attention of thofe who may be employed in
fupplying {hips with provifions, or to captains and the owners
of veffels, and may, in all probability, leffen, if not wholly
remove, an inconvenience fo injurious to our invaluable na-
vigation :—A bag belonging to a powder-mill fell into 4
cauldron of liquid nitre; it was immediately taken out,
plunged into cold water, and hung up to dry: feveral days
after this circumftance the bag was filled with fea-bifcuit
and fent on board a Weft Indiaman, where it was ftowed
away amongft the captain’s flock. The veflel was nine
months out of England before fhe proceeded on ber paflage
home, when fhe got becalmed, and remained fo Jong in that
fituation, that her crew were foreed to be put on half allow-
ance, more particularly fo, as their bread was much deftroyed
by the weavils, and was hourly confuming. The captain at
this time wifhing to make ufe of the bag above mentioned,
which had not been opened fince the fliip left England, or-
dered it to be examined, when, greatly to his furprife, the
whole contents were found to be perfectly found, without
any appearance of haying been injured by any infec what-
ever; a circumftance folely to be attributed to the quality of
the bag.

ANTIQUITIES, &c.

A number of rare manufcripts and other valuable articles
have heen brought to this country by Mr. Cripps, of Suffex,
and the Rev. Mr. Clarke, which we underftand are princi-
pay intended to enrich the library of Jefus college, Cam-

ridge, The whole colleftion made by thefe gentlemen, il-
luftrating

ee

; Apparent Aitra&ion of floating Bodies. 287

luftrating the natural and moral hiftory of the various people
they vifited, in a journey from the 69th degree of north lati-
tude to the territories of Circaffia and the fhores of the Nile,
fills 183 cafes, The botanic part contains the herbary of the
celebrated Pallas, enriched hy the contributions of Linnzus,
and his numerous literary friends. With the minerals are
feveral new fubfiances, and the rareft productions of the Si-
berian mines. Among the antiquities are various infecriptions
and bas-reliefs, relative to obfervations made in the plain of
Troy, and which were announced by M. Chevalier, in France,
in the laft edition of his work. The medalic feries contains
feveral coins of Greece, and of the kings of Parthia, hitherto
unknown. The manu(cripts are in Hebrew, Coptic, Arabic,
Abyfiinian, Perfian, Turkifh, and the language of Thibet
Tartary: and in the Greek and Latin languages are feveral
mauufcripts of the claflics, of the gofpels, and the writings
of the earlieft fathers of the church. In addition to thefe,
the collection contains Greek vafes, gems, feulptures, and
many remarkable Egyptian monuments, from the ruins of
the city of Sais, difcovered by thefe travellers in the Delta
after the evacuation of Egypt by the French: alfo numerous
original drawings, maps, charts, plans, models, and feeds of
many rare and ufeful plants; the habits, utenfils, idols, of
the inhabitants of the Aleutan ifles, brought by Billings to
Ruffia after his expedition to the countries lying between
Kamtfchatka and the north-weft coaft of America, with
many geographical obfervations, the publication of which
was fo long withheld by order of the Ruffian government.

ON THE APPARENT ATTRACTION OF FLOATING
Bopiges. By a Friend to Phyfical Inquiries.

It is.a well known faét, that when bodies which are afloat
upon water come within a {mall diftance of each other, they
will fuddenly ruth together: this fudden approach has ufually
been attributed to a mutual attraction of the floating bodies;
and it is common to float two cork balls in a veffel of water,
for the purpofe of demonftrating this fuppofed attraction.
A few years ago the following experiments were made, with
a ftrong perfuafion that the abovementioned circumftance
was not owing to the attraétion of the cork balls; and if any’
one who is now of opinion that it is owing to a mutual at-
traction of the balls, will make the experiments themfelves,
itis probable that they will have doubts on the fubject, or
totally alter their opinion.

1. June 1797. ‘I'wo cork balls (one larger than the other
confiderably) were floated on water; when brought 7

eac

Galvanifm.

each other, they approached in the-ufual manner, as if by
fome mutual influence. This was expected.

. 2, The larger ball was ftuck on a piece of wire, and was
holden near the {naaller one, which was floating whilft this
(the larger one) was entirely out of the water. There was
under thefe circumftances, not any apparent attraction what-
ever.

3. The larger ball on the wire was then totally immerfed
in the water, and, though near the other ball, there was ‘not
any apparent attraction.

4. The ball on the wire was then raifed partly above the
furface of the water near the floating ball; then the fmall
ball approached, and the ufual appearance of attraction took
place.

The following is offered as an explanation of the above
fa&ts; and is fuppofed to be the chief, if not entire caufe, of
thofe effects :

Round each cork ball, when floating on water, may be
feen an elevated circular mafs of water, raifed probably from

the fame caufe (whatever that may be) by which water rifes:

in bread, fugar,. &c.: now it appears that when thefe two
circular mafles or rings of water touch each other they unite,
and, by endeavouring to form one mals, carry the two cork
balls with them until they touch.
London, Nov. 2, 1802.
GALVANISM.

On the 20th of November profeffor Aldini repeated, int
two courfes, at Mr. Wilfon’s anatomical theatre, Great
Windmill-fireet, formerly that of the celebrated Dr. Hunter,
the galvanic experiments which he performed before the
French National Inftitute, and Jately at Oxford. The firft
courfe, deftined for the medical ftudents, was opened by
Mr. Wilfon, who prefented profeffor Aldini®to his pupils,
with fome obfervations on his interefting difcoveries, The
fecond courfe, which commenced inimediately after, was
honoured by the prefence of his excellency general Andreoffi,
ambaflador of the French republic, accompanied by feveral
gentlemen of his fuite; M. Areyropoli, charge d’affaires of

the Ottoman Porte, Sir William Hamilton, Dr. George”

Pearfon, Dr. Lettfome, and a great many other gentlemen.
Mr. Cuthbertfon aflifted the profeffor in arranging the ap-
paratus, and Mr. Hutchins, a medical pupil, provided the
anatomical preparations. The experiments were performed
with neatnefs and precifion, and gave much fatisfaction to
the {peCtators, who teftified their approbation by loud and
repeated applaules.

} Ses Fe | Se EE a

[ 289

XLIV. Analy/is of the Schiefer[path from Cornwall; to which
is prefixed an Analyfis of Carbonated Lime, and Remarks on
the Means which have been employed to a/certain the Quan-
tity of Carbonic Acid contained init. By Mr. Ricuarp
Puittiips, Member of the Britifh Mineralogical Society®.

From fome experiments made upon the fchieferfpath, I
was induced to believe that it confifted of lime combined with
a much greater quantity of carbonic acid than, according to
the analyfis of Bergman (Eng. edit. vol. i. ps 32.) is contained
in carbonated lime. I refer to his analyfis of this fubftance,
fuppofing it to be the laft, and perhaps the only one ever
made of it, fince it is quoted by Hatiy, Traité d2 Minera-
logie, tome il. p. 128; and by Brochant, tome i. p. 548, as
well as by other late writers on the fubject. By the analyfis
of Bergman, pure carbonated lime confifts of
Carbonic acid = 34

Lime ~ = 55
Water - - il
oOo

~ In order to afcertain the quantity of water, which, as above
ftated, is very confiderable, the following experiments were
made :

~ Exp. 1. 100 grains of pure carbonated lime (double re-
fra¢ting {par) were expofed, in a filver crucible, to a red heat
for about twenty minutes. * On weighing them when cold
they were found to have diminifhed 1°8 grain. _ It will here-
after be fhown that a part of this lofs was probably water :
yet a portion of it is to be attributed to the difengagement of
carbonic acid; for, upon putting the remaining carbonated
lime into water coloured blue by fyrup of violets, the folution
inftantly aflumed a deep green colour.. Hence it appears that
ie method is not to be relied upon in order to diffipate water
only. ie’

Exp. 11. 400 grains of carbonated lime were introduced
into a coated glafs retort, having a receiver adapted to it.
Soon after the application of heat, a very minute quantity of
water appeared in the neck of the retort; but it was entirely

diffipated before it had reached the mouth of it. Owing to
this, and the extreme fmallnefs of the quantity, it was entirely

impoffible to afcertain or even to eftimate its weight. No
More water appeared upon the application of a much ftronger
* Communicated by the Author,
Vou. XIV. No. 56. T heat
January 1803.

290 Analyfis of Carbonated Lime.

heat to the retort. This experiment was repeated with fimi-
lar refults.

Exp. III. To find the quantity of carbonic acid contained
in carbonated Jime, I made ufe of a veffel nearly fimilar to
that defcribed in * page 365 of the 12th volume of the Phi-
lofophical Magazine. :

Into this veflel was put a fufficient quantity. of nitric acid
of the fpecific gravity 1°40, noting at the fame time the
aggregate weight of the vial, tube, and acid; and 1co grains
of fragments of carbonated lime were gradually added to the
nitric acid. When the laft portions of it were decompofed,
on weighing the vial, &c. it had received an addition of 56
grains. Hence 44 grains, which were carbonic acid, were
expelled. On repeating this experiment with quantities of
carbonated lime greater than 100 grains, proportional refults
were afforded. .

Exp. 1V. To determine the quantity of lime, 100 grains
of carbonated lime reduced to powder were put into a platina
crucible, and ftrongly heated in a wind-furnace for about two
hours: the refidaum was pure lime; it weighed 559 grains.
Upon repeating this experiment I obtained a refiduum weigh-
- dng 55°05 grains. Thefe refults differ but little: their mean,
55°475, is therefore aflumed as the quantity of lime con-
tained in Ico parts of the carbonate.

According to the above experiments, carbonated lime con-

tains Carbonic acid - 44
Lime - - 55'475
Water and lofs 525
1007000.

In comparing the above with the analyfis by Bergman
there appears a difference of 10 of carbonic acid and nearly
10°5 of water. Kirwan, (Mineralogy, vol. i. p. 87.) on
remarking the difference of the quantities of carbonic acid)
obtained by himfelf and Bergman, fuppofes the latter em-
ployed fulphuric acid to difengage the carbonic: and this
conjecture feems well founded; for, if carbonated lime be put_

into falphuric acid, the fulphate of lime formed, and rari

down infoluble, fo envelops a part of the carbonated lime-
that the complete aétion of the fulphuric acid is prevented zy
and as it does not appear that Bergman obtained the water
by direct experiment, he feems to have affumed its quantity

* The experiments there related upon the fatin fpar were repeated ;
but it did not appear to contain more than the ufual proportion of carbonic
acid.

from

Analyfis of the Schiefer[path from Cornwall. gt

from the deficiency occafioned by the incomplete action of
the fulphuric acid.

Still apprehending that refults fo diffimilar might arile
from inaccuracy in the method T had employed, more mi-
nute attention was paid to the difengagement of the carbonic
by the ftronger acids. The following experiment was infti-
tuted to determine the quantity of muriatic acid carried over
by the effervefcence it excited, This acid was preferred to
the nitric for two reafons: being very dilute, and its action
confequently increafed, the error is fhown in its greateft de-
gree; and fmall quantities of it are much more readily de-
tected than of nitric acid.

Exp. V. 200 grains of fragments of carbonated lime were
put into muriatic acid of fpecific gravity 1°17 in the vial al-
ready mentioned, having a Woulfe’s apparatus fo adapted
that the carbonic acid difengaged might pafs through water.
After the effervefcence had ceafed, the vial containing the
muriate of lime was heated in water for nearly an bour, in
order to expel the carbonic acid, which, although difengaged
from the lime, was held in folution by the water of the dilute
muriatic acid. By thefe means the lofs was ‘6 more than
when nitric acid of 1°40 was ufed, occafioned by the more
rapid effervefcence. "

To the water through which the carbonic acid had paffed
nitrate of filver was added, which occafioned the formation
of fach a quantity of muriate of filver as, from comparing
the degree of turbidnefs, was nearly equalled by °6 of mu-
riatic acid. ‘The flight diffimilarity evidently refulted from
the evaporation of the water of the muriate of lime by the
heat employed to extricate the laft portions of carbonic acid.

. The ftronger effervefcence which a dilute acid excites, is
not the only inconvenience attending it; the water is capable
of combining with a quantity of carbonic acid, which rea-
ders it neceflary to employ heat, as in the above-mentioned.
experiment, which is totally unneceflary when a concentrate
acid is made ufe of.

Analyfis of the Schieferfpath.

Some fragments of {chieferfpath being put into muriati¢c
acid, ftrong effervefcence took place, and nearly the whole
was foon diffolved : the folution was colourlefs; a very mi-
nute quantity of a finely divided white fubftance remained
undiffolved. The folution, divided into parts, exhibited with
Teagents the following appearances:

ruffiate of potath, a lie precipitate. —
Tinéture of galls, a dark brown precipitate. .
T 2 Ammonia,

292 -Analyjis of the Schieferfpath from Cornwall.

> Ammonia, a fall quantity of reddith browh precipitate.
Oxalate of ammonia, a copious white precipitate.
Sulphuric acid and fulphate of foda both produced plentiful

white precipitates ; he Liter not immediately: the folution,

therefore, contained neither ftrontia nor barytes.

~» Carbonate of potafh alfo occafioned a plentiful white pre-

- “eipitate: upon heating the folution after filtration no further

. depofition took place, as would have done had the folution
‘contained magnefia, "

The infoluble white refidaum was boiled in fulphuric and
‘nitric acids, but neither of them diffolved any part of it:
potath diffolved it entirely : had it been alumina, its ftate of
extreme divifion would have admitted of its eafy-folution in
acids: it therefore appears to be filica. The fame appearance
took place with folution of the fchieferfpath from Germany.

From thefe preliminary experiments it appears that the

fchieferfpath is a carbonated lime intermixed with oxide of
iron and a very fmall quantity of filiea; fo fmall, indeed,
that, had it not always appeared in every folution which was
‘made of the foreign as well as the Englith, I fhould have
been’ induced to fafpest that its prefence was rather acci-
‘dental, than neceffarily entering into the compofition of the
mineral. )
Employing the method which has already been mentioned,
200 grains loft by folution in nitric acid of 1°40 fpecific gra-
vity 86°8 grs. of carbonic acid, equal to 43°4 per cent. Now,
according to the analyfis juft given of carbonated lime, 44
parts of carbonic acid are united to 55°475 of lime: hence
43°4 of carbonic acid muft be combined with 54°718 of
lime, forming together 98-118 of carbonated lime.

The nitric folution was confiderably diluted with water, in
-order to effe& more readily the fubfidence of the filica ; which
being carefully colleGted, afler repeated wafhing, and dried in
a glafs veflel by the heat of an Argand’s lamp, weighed ‘1 of
a grain, equal to ‘o5 per cent, ne

The oxide of iron precipitated by ammonia was fubmitted
toa red heat, and treated with carbonaceous matter {fo as to
render it magnetic: on weighing, it was found equal. to -8
“percent, 00 parts confit of

Carbonate of lime - 98118 ty
Silica - - "O85 Cea
Oxide'ofiron == - 8
98*968
Lofs - ~ 1°03%
| 102°000

XLV. Dew

| [.-298:h,
XLV. Defcription of the. Schieferfpath. By. Antuvr,
Auxin, E/q. Member of the Britifh Mineralogical Society.

SB ecitos re Calcareus fpathum fchiftofum : /Ver-
ner, Argentine: Kirwan. Spath {chifteux: Brochant.

Colour: yery dilute yellowith white ; by being kept for a
few minutes in a red ‘heat, it becomes flightly reddifh white.
" Luftre, internal; fhining pealy. yp

“FraCture: waved-lamellar, © = igs :

Fragments: for the moft part blunt-edged, wedge-fhaped :-
it is tranflucid even when in mafs, and at the edges 1s occa=
fionally tranfparent., It is brittle; may be fcratched by the
nail, and has a flightly unctuous feel : fpecific gravity 2°740.
' This mineral differs from common calcareous {par in its
fuperior brilliancy; and efpecially in the total abfence of the
rhomboidal figure in its fragments. The fpecimen analyfed*,
and from which the above defcription was taken, differs from
the general account of this mineral by Widenman, Emmer-
ling, Brochant, &c. in being more tranfparent: it is probably
from Polgorth tin-mine, and is covered in various parts with
cryftallized oxide of tin and chlorite: on breaking the fpe-
cimen, a fmall quantity of fluor fpar was found. It may be
well to remark, that Cornwall, and probably the fame mine,
has produced a calcareous fpar of the ufual rhomboidal frac-
ture and of a brilliant pearly luftre: it contains. ne filica,
and appears to be lime combined with the ufual quantity of
carbonic acid and a little oxide of iron: fpecific gravity 2°723.

XLVI. 4 /hort Account of Mr:SuitH’s Air-pump Vapour-
bath, By Mr. HENRY JAMES, 9 =

To Mr. Tilloch. - iA

Perr me, Sir, {6 lay before the readers of your Maga
zine fuch an account-of a Philofopbical Apparatus (not Tefs
ufeful than ingenious’) as may in fome meafure corpefpond
with the general intention of fo valuable a publican Jar
__ The Air-pump Vapour-bath, after fifteen years almoft con-
fiant attention, and at a very confiderable expenfe, has at
eh been brought to. fuch a degree of perfection as to be
applicable, with good effeéts, in fhe of the moft dittrefling
complaints to which fuffering humanity is liable. The ap-
plication of this apparatus is now at Jength committed to the
direétion of medical men, fo that, I truft, its good properties
will not, as heretofore, be overlooked ; or, what amounts to
. "© See the preceding article,

\ the

294 Account of Mr. Smith's Air-pump Vapour-bath.

the fame thing, will not, from want of profeffional diferi-
mination, be faffered to fink into oblivion, With this part
of the bufinefs, not being a medical man, I have nothing to
do: leaving it, therefore, in better hands, I fhall attempt,
1ft, Some account of its origin; 2dly, What, 2 priori, might
have been expeéted from it in a philofophical point of view 3
and, laftly, Such an explanation of its principles as, I hope,
may prove that it has a fair claim to its daily increafing po-
pularity. es
Ift. Mr. Smith, of Brighton, my father-in-law, from the
ftory of king Edward, at the crufades, having had the poifon
of an arrow fucked from a wound by the mouth of his fair
queen, long ago conceived the idea of this Apparatus. His
firit attempts at putting it in execution were rude, and almoft
laughable: but the great engine of his mind, on this as on
other occafions, rofe fuperior to all difficulties ; and at length
the accomplifhment of his objeé&t rewarded his perfeverance ¢
for what will not perfeverance achieve ! j (a tay
With every poffible refpeét for the faculty, may we’ not
here take the liberty to exprefs our furprife that they fhould
have left this ext nfion of the powers of the cupping-glafs to
be difcovered by an individual altogether unacquainted with
the principles of their fcience ? For the intelligent reader
will prefently be informed, that the Air-pump Vapour-bath
aéts upon the fame principle as the cupping-glafs; and, to
ufe the inventor’s own words, ‘is neither more nor Jefs
than a cupping-glafs on a large feale.”’ This defcription is
accurate as far as it goes; but Mr. Smith did not at the time
take into account, that by means of his apparatus, fomenta¢
tion can be applied, and its temperature regulated, with a
degree of certainty and accuracy which, I apprehend, were
never attained, or fo much as expeéted, before this happy
difeovery. For I think it requires little fagacity to obferve,
that in fomenting with flannels the temperature can never be
for a minute equably preferved; but the limb muft be ex-
pofed to various degrees of heat andcold during the applicae
ton.
adly, To thofe of your readers who have vifited the tops of
high mountains, it is unneceffary to defcribe the effeéts of the
diminution of atmolpheric preffure. M. de Sauffure, who
has publifhed an interefting account of his journey up Mount
Blanc, ftates it moft forcibly. He found that the mercury
in his barometer funk to 16 inches anda line (177145 inches
Englifh), and that the air had confequently little more than
half the preffure of that on the plains. In fuch fituations, the
@tteries on the furface of the body, deprived of their accuf-
| somed

%

Account of Mr. Smith's Air-pump Vapour-bath. 295

tomed preffure, do not, as ufual, refift the impetus given to
the blood by the contraction of the heart, which has been
found to occafion difficulty of refpiration, violent retching,
and even vomiting of blood.

I need not tell you, that the preffure of the atmofphere
in its mean ftate is equivalent to a weight of 15 pounds to
every {quare inch. It has thence been computed, that the
preflure of the circumambient fluid upon the furface of the
whole earth is equivalent to the weight ofa globe of lead 60
miles in diameter. If every {quare inch of the human body,
therefore, fuftains a preffure of 15 pounds, every fqnare foot
mut fuftain that of 2160.pounds; and according to this cal-
culation, every ordinary fized man has to fupport a weight of
between ,15 and 16 tons for bis common load. Such an
enormous preflure, if not counterbalanced by the elaflicity of
the air within our bodies, would crufh usin a moment. If
a portion of this preflure be removed from any part of the
body, as is the cafe, for inftance, when a leg or arm is en-
clofed in the cylinder of this Apparatus, and the air partially
extracted, the effect of this unequal preffure foon becomes
(perceptible to the patient. Should the exhauftion be carried
to its utmoft extent, it requires no ftretch of imagination to
conceive the effects that would be produced !

The quantity of atmofpheric preilure on the human body
fometimes. varies near a whole ton, from natural caules.
When it is diminifhed fo much, many people, pariicularly
the nervous, find themfelyes inaétive and irritable. It is
fomewhat furprifing that the fpring of the intefnal fluid,
mentioned aboye, as counterpoifing atmofpheric preflure,
fhould exaétly balance it when artificially augmented, and
even when naturally diminifhed, but not when ariificielly
diminifhed. Thus, though we perceive no evident diften-
fion of the blood-veffels on the furface of the body from
the natural diminution of atmofpheric preflure; yet the cafe
is widely different when the diminution is artificially pro-
duced, as can be effected to any extent within the cylinder
of this Apparatus. Thus animals in'the receiver of an air-
pump become immediately uneafy, and can live but a very
{hort time in air artificially deprived of no more of its preflure,
than by the barometer, appeared to take place on the top of
Mount Blanc. I am aware that this phenomenon may he
accounted for on other principles; namely, that a certain
quantity of oxygen gas diffufed through a given {pace, will not

uftain anieial {a half fo long as twice the quantity diffuled
oe the fame fpace. There may be fomething in this;
but, [ hunrbly think, it is not fufficient alone to account for

IT 4 the

296 Account of Mr. Smith’s Air-pump Vapour-bath.

the immediate uneafinefs and early death of the enclofed
animal. : .

What proportion of thefe confequences is to be attributed
to retarding the impetus of the blood returning to the heart,
and confequently producing an earlier collapfe of that organ,
T leave to anatomifts and phyfiologifts to determine. | |”

It was once the fafhion among phyficians to explain the
funétions of the human body by mechanical principles alone
to confider it as an hydraulic machine, and its fluids as af-
cending and defcending by the ordinary powers of fuch en=
eines: From having applied the laws of dead matter to the
functions of the living body too extenfively, they bewildered
themfelyes, and contradicted each other. Neverthelefs, in
this age of perfeéted anatomy and improved phyfiologv, we
find Dr. Darwin, who is faid to have done as much for the
latter fcience as fir Ifaac Newton did for natural philofophy,
propofing ‘ to {till the a€tion of the heart and arteries by
mechanical means.” This, he fuppofes, may be effected by -

~ fufpending a bed fo as to whirl the patient round, with his
head neareft the centre of motion. For this purpofe, a per=
pendicular fhaft might have one end pafs into the floor, and
the other into a beam in the ceiling, with a horizontal arm,
to which a fmall bed might be attached. The effects of
whirling a patient in this fituation, fo'as by the centrifugal
force to propel the blood from the fuperior’ into the inferior
parts of the body, would certainly be confiderable, and, he
obferves, might probably add to the means of curing fevers.

Be this as it may, the relief which many perfons have ex-
perienced from the ufe of the Air-pump Vapour-bath, autho-
rizcs me to affirm, that it is capable of producing, with eafe
and fafety to the patient, all the good effeéts which Dr. Dar-
win could poflibly expect from his centrifugal machine.

It would neither be compatible with my attainments, nor
your plan, to defcribe the medical ufes of the Air-pump Va-
pour-bath. I fhall therefore barely mention, that it has been
found extremely beneficial in a variety of difeafes {pecified in
a treatife lately publifhed, intitled, ‘* Fa€ts and Obfervations
refpecting the Ufe of Smith’s Air-pump Wapour-bath in
Gout, Rheumatifin,Palfy, &e. &e."%

Lattly, It only remains that I offer you fome explanation
of the mechanical principles of the Apparatus,according to
the references on the annexed plate.

Explanation of the Plate.

Fig. 1. (Plate VII.) a view of that end of the machine to
which the exhaufter, &c, are affixed. A, the body of the
machine.

Account of Mr. Smith's Air-pump Vapour-lath. 297

machine. B the boiler containing the fluid, the fumes of
which are thrown into the cylinder, through the ftop-cock H,
and heated by means of a fpirit lamp C, which ought always
to be withdrawn immediately on turning the ftop-cock G,
hereafter mentioned. D athermometer, {howing the tem-
perature of the fumigation. E the exhaufter for producing
a partial vacuum within the cylinder, after tne fumigation has
continued a proper time. F the efcape-valve of the exhaufler,
to which a flexible pipe is adapted to convey the air from the
chamber, if vitiated by the nature of the affection for which
the application is made. G the ftop-cock of the boiler.
H another ftop-cock ‘to prevent the valyes of the exhaufter
from being injured by the hot fumes, as they enter the ma-
chine during the fumigation.

Fig. 2. a perfpective view of the machine from the other
end, where the limb is admitted. I the body of the machine,
made of ftrong copper tinned in the infide, ordinary tinned
iron itfelf not being fufficient, in all cafes, to refift the preflure
of the atmofphere. | K the mouth of the machine, te which
is attached a ftrong bladder, cut fo that one end of it may go
over, and be firmly fecured to it by means of a ligature; the
other fo that it may be drawn over the limb, when pafled
through it into the machine, and fecured upon it by means
of a roller.

The conftrustion of the machine juft defcribed, is adapted
to the leg or arm only. Its principle, however, may be ex-
tended, and one might be made to include a greater portion
of the body. Such an attempt is making. One of the moft
obvious confequences of its application muft be, a temporary
expanfion ‘of the veffels of the part from whence fo great a
preffure is removed. This mutt powerfully affift nature in
removing obftructions formed in them, which often fpeedily
produce inflammation, and terminate in fuppuration and
abfcefs.

Dr. Hamilton, of the London Difpenfary, has obferved,
that the mode in which it niuft act is agreeable to found the-
ory, and that the more it is applied to praétice, the oftener
will facts occur to recommend it.’ That eminent pbyfician
*‘ not only views it as valuable to remove local affections of
the extremities, but alfo to afford relief in other parts of the
body, where obftru€tions may have taken place.” In the
fame letter he obferves, that “ the machine, by having a
condenfing pump fixed to it, may be wled as a bracer, and
that with’ beneficial and powerful efleéts.” This may be
done merely by reyerfing the valves in the pump.

Thefe
6.

298 ‘99 Memoir on the Supply and

~ Thefe confiderations, however, I -fhall leave to your mes
dival readers, to whom I with to fubmit this important query
—Is the application of the principle zuft alluded to, ever likely
to be of ufe in relieving the ruptured ? d
No, 5, Cumberland Place, I am, Sir, yours, &ee

New Road, Marylebone, Henry JAMES,
January 8, 1803. shoe

XLVII. Memoir on the Supply and Application of the Blow-
pipe. “By Mr. Ropert Hare jun. Member. of ihe
Chemical Society of Philadelphia.

[Concluded from, p. 245.]

Terk avirniotc blow-pipe may be filled with jany..of
the gales, by exhaufling them from the inverted jars, of the
pneumato-chemical apparatus: and if it be defired to confine
different {pecies of gas, by clofing the cock of communica,
tion between the compartments, one of them may be filled
with one kind of gas, and afterwards, by turning the hood,
the other compartment may he filled with another kind, To
make this underftood, let a, fig. 5, be a pneumato-chemical
tub, with a fhelfc, and an inverted glafs jar 4. _ Suppofe
that the tub were filled with water, and the jar with gas.
Lute the pipe J, fig. 1, to the mouth of the fuction-pipe at I;
pafs the fyphon L under the jar, as may be obferved in fig. 5,
and then extend the bellows. The bellows will become filled
with the air of the jar; and this being difcharged into that
compartment of the cafk which is oyer the open fide of the
hood, the bellows will be ready fer another extenfion ; the
repetition of which would foon exhauft the jar of its air, al-
though it fhould be of the largeft fize.

This method of filling the machine is very convenient in
a laboratory well fupplied with pneumato-chemical apparatus.
But itis a principal convenience of the hydroftatic blow-pipe,
that it may be filled with any gas, immediately from the re-
tort, bottle, or matrafs, made ufe of in obtaining it. Let D,
fig. 6, be a feparate reprefentation of the pipe D, fig. 1.
Let B. be a matrafs containing the fubftance from which the
air is to be obtained, and Jet C be a fyphon luted to the neck
of the matrafs. The air iffuing from the matrafs muft be
emitted from the mouth ofthe fyphon at the lower end of
the pipe D. Suppofe that this pipe were in its proper fitua-
tion at D, fig. 1, the air iffuing from the mattafs would be
difcharged

eee ee ee ee ee

—s oo

Application of the Blow-pipe. 299

difcharged into that compartment of the cafk under which
the mouth of the fyphon fhould be placed, and if the cock
at Y fhould be clofed, this compartment alone would become
filled ; but if'this cock fhould be open, the air would divide
itfelf equally between both compartments. It muft be ob-
vious, that while one matrafs and fyphon are empioyed in
filling one compartment with one fpecies of air, the bellows,
or another matrafs and fyphon filled with different fubftances,
may be employed in filling the other compartment with an-
other fpecies of air; and thus the oxygen, and hydrogen
gafes or oxygen yas, and atmofpheric air, may at the fame
time be confined in the fame veffel without their mixing with
each other.
_ Thofe who defire to experiment largely with oxygen gas
will find it advantageous to make ufe of a caft iron matrafs,
with a fhort and large neck narrowing inwards, and about
fifteen inches of a gun barrel. The neck of the matrafs being
made large and fhort, it will not only be eafily filled, but will
be readily freed from any caput mortuum which may be left
in it. The gun-barrel muft be ground to fit the neck of the
matrafs.
The fyphon for conveying the gas into the cafk may be
fitted to the eun-barrel with a cork.
The hildlophical world has been for fome time acquainted
with the intenfe heat produced by combuftion fupported with
oxygen gas. By means of the hydroftatic blow-pipe, every
artilt may, witb little trouble and expenfe, avail himfelf of
the intenfe heat produced ‘by this combuftion *.
_ Probably there are not at prefent many operations in the
‘arts which require greater heat than may be produced by the
ordinary means; but it is certain that the knowledge of a
procefs cannot precede an acquaintance with the heat necef-
fary to effect it; and this moft intenfe fire being placed
within the reach of the artift, it is highly probable that cafes
may be difcovered in which it may be applied with conve-
nience and utility.

The moft convenient way of making ufe of oxygen gas for
fmall operations, is to fupply one of the compartments of the
hydroftatic blow-pipe with that gas; to retain the gas thus
confined for thofe moments when the greateft heat is re-
quired; and, by means of the other compartment, to make

* Ina former page I mentioned the gafometer of Lavoifier as bein
too complicated for ordinary application to the {upply of oxygen gas.
fhould alfo have noticed the apparatus of Sadler and the gafometer of
Seguin; but, if [ am not miftaken, thefe, although very ingenious inven-
tigns, are liable to the fame obje€tion,

) ule

1
goo Memoir on the Supply and.

ufe of atmofpheric air when the heat produced by it. is
fufficiently intenfe. Jt mutt be obvious, if the conical
mouths, O,o, of the pipes M, N, Q, m,n, 0, fig. 1, be far
nifbed with flraight mouth-picces, that any Jamp or candle
placed on the ftand TV may be readily fhifted fromy one
mouthpiece to the other, when it fhall be defired to expofe
any fubjeét fucceflively to the heat produced by atmofpheric
air and oxygen gas, ae
If it be withed to make ufe of the heat produced in the
combuftion of charcoal with oxygen gas; after haying con-
fined a fufficient quantity of this gas, it will be neceflary to
fix in the conical mouth of the pipe, communi aiiae with
the compartment containing the gas, the larger end of a
common brafs blow-pipe, the orifice being: directed down-
wards. Under this orifice the body to be acted on muft be
placed, {fnpported by a piece of charcoal, in the form of a
parallelopiped, the charcoal being ignited in the part conti-
guous to the body. Things being thus arranged, by turn .
ing more or lefs the cock of the pipe in which the blow-pipe
fhall be fixed, a ftream of oxygen may be precipitated on the
burning fpot, with the proper degree of rapidity *.
This method of fupporting the-combuftion of carbon with
oxygen gas is nearly the fame as that by which the celebrated
Lavoifier performed: his experiments; excepting that in the
place of the hydroftatic blow-pipe he made ufe of his gafo-
meter. en's '
In the introduGtion to this paper it was mentioned that
fome experiments had been performed which feemed to in-
validate the opinion that the employment of larger quantities
of oxygen gas would be the only means. of inereafing the
power of caloric. I fhall proceed to give an account of thefe
experiments, but will firft retrace the ideas which led to them.
In operating with the combuftion of carbon and oxygen
gas, great evils were obferyed to refult from the difficulty of
placing the fubject of the operation in the-focus of the heat,
without interrupting the ftream of air by which this heat was
fupported. Not only was the focus widened by this interrup-.
tion, and the intenfenefs of the heat thereby leflened; but
the ftream of air oxidated thofe fubftances which were com-
buttible, and cooled thafe which were otherwife, in the places
where jt impinged preyianfly to its union with the charcoal.
* In detailing theufes of the hydroftatic blow-pipe, it may be proper
to mention the facility which it gives to the employment of the gafes for
medical purpofgs. When this machine is filled with any gas, the bag to
be made ufe of in refpiring it may be inflated by fixing it to the mouth of
the pipe of delivery communicating with the gus.
Added

Application of the Blow-pipe. ot
Added to this, the charcoal was fo rapidly confumed, that the.
es aéted on became fo much buried, that it was diffi-
_ €ult to follow it with the eye, or the orifice of the pipe: and
~fome fubftances were obferved to run into the pores of the
_ coal, and elude examination. _
__. To ayoid thefe evils, it was thought. defirable that means
~“Mright be difeovered of clothing the upper furface of any body
which might be fubjected to this fpecies of operation with
fome burmng matter, of which the heat might be equal to
that of the incandefcent carbon, with which thie lower furface
might be in contaéts or by which bodies might be expofed
on folid fupports to a temperature equal or {uperior to that
of the porous charcoal uniting with oxygen.

It foon occurred that thefe defiderata might be attained by
means of flame fupported by the hydrogen and oxygen gafes 5
for it was conceived that, according to the admirable theory
of the French chemifts, more caloric ought to be extricated
by this than by any other combuftion.

By the union of the bafes of the hydrogen and oxygett
gafes, not only is all the caloric of the oxygen gas evolved,
but alfo a much larger quantity, which muft be neceflary to
give the particles of the hydrogen their fuperior power of re-
‘pulfion. The product of this combuttion 1s water in the ftate
‘of fteam, which retains heat fo flightly, that it acts merely as
‘a vehicle to deliver it to other bodies. What is neceflary to
prefetve to water its form of fluidity, is the only portion of
the caloric extricated in this combuftion, which is perma-
nently abftracted.

The combuftion of carbon with oxygen gas has been
hitherto confidered as the hotteft of all fires, The caloric

— Po in this eafe proceeds from the oxygen gas alone,
oa ae product of this combuftion is carbonic acid gas,
which ab(tra&s the large quantity of caloric, neceffary to give
» it the form of permanent air, but which adds nothing to the
heat of the combuftion. | Hence it is evident, that more ca-
4, Ioric is evolved, and lefs abftraéted, in combuftion fupported
Wer the hydrogen and oxygen gafes, than in that {upported by
; “oygen gas and earbon. ;
ty. ‘However, the intenfenefs of the heat of combultion is not
only dependent on the quantity of caloric extricated, but alfo
on the comparative fmallnefs of the tiine and fpace in which
the extrication is actomplifhed, But in this refpeét the
aériform combuftible bas. obvioufly the advantage over thofe
which are folid, as its fluid and élaftic properties render it
fulceptible of being rapidly precipitated into the focus of
combutftion,

.

gc2 | Memoir on the Supply and

combuttion, and of the moft {peedy mixture with the oxi-
dating principle when arrived there.

The opinion of the intenfenefs of the heat produced by the
hydrogen and oxygen gafes thus upheld by theory, derives
additional fupport from the practical obfervation of the great
heat of a flaine fupported by hydrogen gas while iffuing from
a pipe; and alfo of the violent explofion which takes place
when it is mixed with oxygen gas and ignited; for it appears
that this explofion can only be attributed to the combination
of an immenfe quantity of caloric with the. water which is
either held in folution by thefe gafes, or formed by the union
of their bafes.

Such was the reafoning which originated the defire of em-
ploying the flame of the hydrogen and oxygen gafes. But
before this could be accomplifhed it was neceflary to over-
come the difficulty of igniting a mixture of thefe aériform
fubftances without the danger of an explofion. It was for
the purpofe of furmounting this difficulty that the hydroftatic
biow-pipe was furnifhed with two compartments, by means
ef which the machine might be at the fame time charged
with different fpecies of air, without any poffibility of mix-
ture, One of thefe compartments being fupplied with oxy-
gen and the other with hydrogen gas, two common brafs
blow-pipes a,b, fig. 8, were joined at their orifices to two
‘tubular holes in the conical fruftum of pure filver c, of which
the mean diameter is one-third, and the length is three-
fourths of an inch. ‘The diameter of one of thefe holes is
large enough for the admiffion of a common brafs pin. The
other hole 1s a third lefs. They commence feparately on the
upper furtace of the filver fruftum near the circumference,
and converge fo as to meet in a point at the diftance ofa line
and a half from the lower furface. In the fpace between
the lower furface and the point of meeting, there is a per-
foration of the fame diameter as the larger hole. The man-
ner in which this perforation and the tubular holes commu-
nicate one with the other, may be underftood from the lines
in the form of the letter Y, in the tranfparent reprefentation
of the filver conical fruftum at d. The pipes ab were then
fitted. into the mouths O, 0, of the pipes of delivery, fig. 1;
fo tbat the blow-pipe inferted into the larger hole of the fruf-
tum fhould communicate with the compartment containing
e hydrogen gas, and that the other fhould communicate
vith that which contained the oxygen gas. The cock of the
communicating with the hydrogen gas was then turned
das much was emitted from the orifice of the cylinder

' as

Application of the Blow-pipe. 303

as when lighted formed a flame fmaller in fize than that of
acandle, Under this flame was placed the body to be acted
on, fupported either by charcoal or by fome more folid and
incombuttible fubftance. The cock retaining the oxygen gas
was then turned, until the light and heat appeared to have
attained the greateft intenfity. When this took place, the
eyes could fcarcely fuftain the one, nor could the moft refrac-
tory fubftances refift the other.

However, it is worthy of notice that the light and heat of
this combuftion do not become evident until fome body is
expofed to it, from which the light may be reflefted, or on.
which the effect of the heat may be vifible. This is not the
cafe with combuftion fupported by oxygen and carbon; for
no fooner is a ftream of oxygen gas direéted on ignited car-
bon, than an effulgence is produced, which imprefles the
mind of the beholder with an idea of the greateft heat being
produced by it.

It is in this different appearance of thefe different fpecies »
of combuttion that we may difcover the reafon why philofo-
phers have neglected the one, while they have beftowed much
attention on the other *.

In lieu of the conical fruftum reprefented at-cd, that at
de may be ufed. The tubular holes of this laft-mentioned
fruftum do not meet, but deliver their air, at feparate orifices,
into an excavation in the lower part of the fruftum. The
dotted lines reprefent the tubular holes, and the arched line
the excavation. This 1s about three lines in diameter, and
enters into the filver about the famedifiance.

At f are reprefented pipes which are ufed for the fufion of
platina, or fubjeéts of the larger kind. They confift of a large
and a fmall pipe, the orifice of the one being inferted into
that of the other, as may be underftood from the dotted lines
near f, )

The purity of gafes contained in the hydroftatic blow-pipe
may be at any time examined by charging eudiometers from
the fyphon and leathern pipes hanging to the cocks ZZ, fig. t.
T hefe cocks are foldered to curved pipes, one of which is
reprefented in the figure. By turning the cocks roynd, the

* The inferiority of the light emitted by the flame of the hydrogen and
oxygen gafes, to that which irradiates from bodies expofed to its action,
adds one to the many inftances in combuftion in which the quantity and
colour of the light extricated do not feem to be fo much dependent on the
quantity of oxygen gas confumed, as on the nature of the fubftances hedted
or bumed. In this, therefore, we may find fupport for the idea, that the.
light extricated by fire, or emitred by heated bodies, proceeds-not only

from the decompofition of pure air, but from that of the combuflibie, ax
the fieated bodies themfelyes.

mouths

304. Memoir on the Supply and

tnouths of the curved pipes may be brought down to the fur-
face of the ivater; this gives a facility to the difcovery of any
heavier gas which may be mixed with one which is more
light, as the fluid, whofe fpecific gravity is greater; will be
found on the furface of the water:

I fhall now defcribe the changes effefted on the moft fixed
and refraétory fubflances by the flame of the hydrogen and
oxygen gafes,

In order to avoid a tediotis recurrence to an awkward
phrafe; I fhall generally, in the fubfequent part of this paper,
diftinguith the flame of the hydrogen and oxygen gafes by
the appellation of ga/eous flame:

By expofure to the galeous flame, either on fupports of
filver or of carbon, barytes, alumine, and filex, were com-
pletely fufed.

The produéts of the fufion of alumine and filex were fub=.
ftances very fimilar to each other, and much refembling white,
enamel, BY 3) .

The refult of the fufion of barytes was a fubftance of an
afh-coloured caft, which after long expofure fometimes ex-
hibited brilliant yellow fpecks. If it be certain that barytes
is an earth, thefe fpecks muft have been difcoloured particles
of the filver fupport, or of the pipes from which the flame
iffued,

Lime and magnefia are extremely difficult to fufe, not only
becaufe they are the moft refractory fubftances in nature, but
from the difficulty of preventing them from being blown on
one fide by the flame: neverthelefs, in fome inftances by ex-
pofure on carbon to the eafeous flame, {mall portions of thefe
earths were converted into black vitreous mafles. Poflibly
the black colour of thefe produés of fufion may have been
eaufed by iron contained in the coal; for in the high tem-
perature of the gafeous flame, a powerful attraction is reci-
procally exerted by iron and the earths.

‘Platina was fufed, by expofure on carbon, to the combuf-
tion of hydrogen gas and atmofpheric air. But the fufion of
this metal was rapidly accomplifhed by the gafeous flame,
either when expofed to it on carbon or upon metallic fup-

rts,

A fmall quantity of this metal in its native granular form,
being ftrewed in a filver fpoon, and paffed under the gafeous
flame, the track of the flame became marked by the con-
glutination of the metal; and, when the heat was for fome
time continued on a fmall fpace, a lump of fufed platina be-
game immediately formed. ;

About two penny-weights of the native grains of ed

when

Application of the Blow-pipe. 305

when fubjeSted to the gafeous flame’ on carbon, became
uickly fufed into an oblate fpheroid as fluid as mercury.
his fpheroid, after being cooled, was expofed as before. It
became fluid in lefs than the fourth of a minute.

Had | fufficient confidence in my own judgment, I fhould
declare, that gold, filver, and platina, were thrown into a
ftate of ebullition by expofure on carbon to the gafeous flame;
for the pieces of charcoal on which they were expofed became
wafhed or gilt with detached particles of metal in the parts
adjoining the {pots where the expofure took place. Some of
the particles of the metal thus detached exhibited fymptoms
of oxidation.

As the fufion of lime and magnefia by expofure on carbon
was accomplifhed with great difficulty and uncertainty, it
became defirable that means might be difcovered of effecting
this fufion with greater eafe.

By the union of the bafe of oxygen with iron, the whole
of the caloric of this claftic fluid is fuppofed to be extricated.
This confideration, together with fome praétical remarks on
the heat of burning iron, induced me to employ the com-
buftion of this metal in conjunétion with that of the hy-
drogen and oxygen gafes.

Some pieces of iron wire, each of about half an inch in
length, were quickly thrown into fufion and rapid combuf-
tion by expofure on carbon to the gafeous flame. When
either lime, magnefia, barytes, alumine, or filex, were thrown
on the iron in this ftate, they became inftantly melted and
incorporated with the metal. It remains a queflion whether
in this cafe the earths were fufed or diffolved, and whether
the fubftances which refulted from their union with the iron
were mixtures or combinations. If they were combinations,
according to the prefent nomenclature, they fhould be deno-
minated ferrurets.

The difficulty of igniting fome fubftances which are only
fufceptible of combuftion at very high degrees of heat, has
hitherto excluded them from the laboratory. By means of
-the gafeous flame, fuch fubftances may be employed with
ithe greateft facility in fmall analytical operations.

Of the nature of the fubftances above deferibed are the
carburets of iron and fome peculiar fpecies of native coal.

Among the carburets of iron, the Englifh plumbago ts
eftcemed the belt. Some pieces of this. fubftance, obtained
from the beft Englith black-lead pencils, were readily thrown
into combuttion by expofure to the gafeous flame either on
carbon or on fome larger pieces of American plumbago. It
was found that cither lime or magnefia was fufible when

#@ Vor. XIV. No. 56. U expoted

305 On the double Refraétion of Rock Cryftal.

expofed to the fire thus produced. This, however, may have
been caufed by the iron contained in the carburet; for the
fufed earths and plumbago generally adhered to each other.
There is a peculiar fpecies of native coal found on the
banks of the Lehigh in this ftate, which it is extremely dif-
ficult to ignite; but when expofed to a high degree of heat,
and a copious blaft of air, it burns, yielding an intenfe heat
without either fmoke or flame, and leaving little refidue. By
expofure to the gafeous flame on this coal, both magnefia and
lime exhibited ftrong fymptoms of fufion. The former af-
fumed a glazed and fomewhat globular appearance. The
latter became converted into a brownith femivitreous mafs.

The heat of the gafeous flame is very much dependent on
the proportional quantities of the gafes emitted. On this
account, the perforations in the keys of the cocks N,n,
fiz. 1ft, fhould be narrow and oblong, to admit of a more
gradual increafe or diminution in the quantity of gas emitted,

I have now concluded my communications on the fubjeé&
of this paper, and fhall be happy if they have been found
worthy of the time and attention beflowed on them by the
fociety. ; .

XLVIII. On the double Refraétion of Rock Cryfial, and an-
other dioptric Property of that Mineral Subjlance. By-C. P.
ToRELLI DE Narcl, attached to the Council of Mines*,

Douvste refraétion, that fingular property of rock eryf-
tal t, and of feveral other minerals, has long engaged the at-
tention of mineralogifts and philofophers, though they em-
ployed it in no other manner than as a diftinguifhing cha-
racter. C, Haiiy fayst: .** It would be difficult to find a
more ftriking charaéter than that deduced from double re-
fraction, fince it depends on the eflence of the minerals in
which it exifts.”’

C. Rochon is the firft philofopher who employed this pro-
perty of rock cryftal to meafure fmall angles; and he read on
“the 26th of January and gth of April 1777, to the Academy
of Sciences, two memoirs on the application he made of it,
‘and the: exaét refults he obtained. This difcovery mutt be
-of the greateft utility, if means fhould be found to conftruét
the inftrument he invented at fo moderate a price as to bring

* From the ‘Yournal des Mines, No. 66.
+ Limpid hyalin quartz, Hatiy Traité de Mineralogie, vol. ii. ps 427+

t Vol. i: of his Treatife, p. 254.

~

Y

>

On the double Refraétion of Rock Cryftal. 307

it within the reach of thofe who might have occafion to mea-
fure angles with it.

A defire to accomplith this object induced me to undertake ©
fome refearches in regard to the cutting of rock cryftal, and
experiments on its double refraGtion, founded on thofe made
by Beccaria and Rochon. With rock cryftal alone I formed
mediums doubly refringent. This is the name which Rochon
gives to thefe inftruments cut cylindrically and compofed of
two or three prifms of this fubftance, which are perfectly
achromatic, and produce very ftrong double refraction. [
conftruéted one with three prifms, in which the angle of
double refragtion is one degree eight minutes: and I find
that larger may ftill be obtained.

I fhall not here indicate the direCtion in which TI cut my

~ different prifms of rock cryftal in order to obtain the maximum

of double refraétion, becaufe I have {till fome experiments to
terminate before I can acquire a thorough knowledge of them.
Among thofe which I cut for my experiments, there is one
which produces effects fo fingular that I think it my duty to
defcribe it. ; ‘

This prifm, the fection of which is an ifofceles triangle,
has one of its angles obtufe, and of more than 100 degrees.
When one looks through the two faces which form the ob-
tufe angle, and in a direction parallel to the face oppofite to
it, the objeét appears neither difplaced nor fenfibly coloured,
but only inverted in {uch a manner, that what is on the right
appears on the left; and vice verfa. If a capital L, for ex-
ample, cut out and applied to the pane of a window, be
looked at, the horizontal line of that letter, inftead of being
on the right below the vertical one, appears to be fituated on
the left. By continuing to look at this letter, if the prifm be
turned on itfelf, and in fuch a manner as if it were traverfed
by an axis parallel to the direétion in which the letter is
viewed, the image of the letter turns at the fame time as the
prifm ; but it moves twice as quick—fo that, if the prifm
makes one turn, the image of the letter makes two. I made

‘ other very fingular experiments with this prifm ; but as it

would be too tedious to detail them here, I fhall referve them
for a memoir, in which I fhall explain the means I em-
ployed to afcertain the rules which muft be followed to cut
rock eryftal in the direétion that produces the maximum ot

* its double refraétion, and to be able to conftruct, without

repeated trials; the inftrument invented by Rochon, to mea-
fure, with very great precifion, diltances of every kind.: I
{hall treat of its application to mines; and fhall deferibe the
‘ U2 method

308 On the double Refraétion of Rock Cryflal.

method I purfued to meafure the deepeft wells and the longeft
galleries.
I fhall conclude this note with a fuccinét account of fome
experiments which I made with the ifofceles prifm of rock
cryftal already mentioned. By applying it to a fimple ca-
mera ob/cura, the objects painted in an inverted pofition, when
this prifm is not ufed, are made to appear in their proper
fituation. By adapting it to alironomical telefcopes, the fame
effect will be produced in regard to objects, which, when feen
through the two convex glafles that compote it, appear inverted.
This prifm fupplies the means of {hortening telefcopes de-
ftined to view terre(trial objeéts, becaufe, by employing it
with a convex eye-glafs only, and an objeét-glafs fimple or
achromatic, inftead of three, four, or-five eye-glaffes, objects
which without its interpofition would have appeared inverted,
will be feen in their proper pofition, By thefe means, one,
two, three, or even four eye-glafles would be faved, and the
teleleope might be thortened by nearly the whole Jength oc-
cupied by thefe eye-glatles. Light alfo will be gained; for
this prifm oceatfions no lofs in this refpect, the matter of
_which it is formed being exceedingly tranfparent; nor will
any thing be loft in regard to diftinctnefs; for, as the prifm
1s very pear the eye, the faults which might arife from any
_inexactnets in the polifhing of its two furfaces will not be
-fenfible.

In employing this tclefcope it muft be remembered, that
at the fame time that it inverts objects by turning them up-
fide down, it turns them from right to left, and what appears

-,on the right in the field of the telefcope is really on the left :

_ for example, if a man going from right to left be yiewed with
it, he will appear in the telefeope as if going from left to
right, but in bis natural fituation: whereas, 1f viewed with
the fame telefcope, taking from it the prifm of rock cryttal

_ and leaving only the cye-glafs which inverts the objeéts, the
man would appear. not only to be proceeding in a dire&tion
contrary to that in which he really is advancing, but he would
appear alfo inverted—the common effect of telefcopes whicla
have only a convex eye-glals.

Expecience alone can {how whether this method of fhort-
ening land telefcopes can be as ufeful as it appears curious,
aud whether it, will be poffible to conftrug one at fuch a

- moderate price as to maintain a competition with common
telefcopes, without which this inttrument would remain
among the uumber of thofe, difcoveries which are rather

. eurious than ufeful.

XLIX. Pre-

[. 309, ]

XLIX. Preparation of the Phofphuret of Lime. By
J.B. Van Mons*.

Puospaurer of lime affords to the amateurs of amufing
chemiftry a curious compound, on account of the property it
has of difengaging, when a few bits of it are thrown into
water, a quantity of gafeous bubbles, which, on reaching
the furface of that liquid, inflame fpontaneoufly with a beau-
tiful white flame, and give rife to fucceflive detonations,
which may be compared to a running fire of mufketry. But
the preparation of this phofphuret is often unattended with
fuccefs on account of the air, which, by following the ufual
procefs, cannot be excluded’from the veflels, and which ox-
idates and even acidifies the phofphorus ; in which cafe, the
combuftible lofing its action on the water, no detonating gas
is engendered; and the correction, by which the inconye-
nience of oxidation is avoided, by putting the phofphorus at
the bottom of the veflel, and the lime at the top, does not
give a homogeneous product, but a faturated:phofphuret, by
the vaporization of the phofphuret, which brings it to a ftate
improper for uniting itfelf with the lime. Thefe different
obliacles may be avoided by proceeding in the following
manner:

Fill a fmall glafs matrafs, with a flat bottom and a long
narrow neck, two-thirds, with one part of carbonated lime
(white marble, wafhed chalk, or prepared oyfter-fhells).
Place the matrafs in a fand-bath, and apply a heat capable
of expelling the carbonic acid from the lime. When you
think that the decarbonization is near an end, introduce in
portions a third part of phofphorus, at very {mall intervals,
and conftantly maintaining the matter at a dark red heat.
The phofphorus fufed, eh prevented from burning by a re-
mainder of carbonic acid gas which is difengaged from the
lime, diffufes itfelf throughout the whole mafs of the mat-
ter, contracts an union with the lime, lofes its volatility, and
forms phofphuret, After the whole phofphorus is intro-
duced, Jet the fire be fuddenly flackened, and fiop the ma-
trafs with a flopper having a pneumatic valve to prevent ac-
cefs of the air, and to fufler to efcape the gas which the mat-
ter that remains fome time puffed up continues to difengage.
When the matter is fufficiently cooled, take it from the
matrafs, and put it, taking care not to touch it with the

# From Yournal de Chimie et de Phyfique, par J. B. Van Mons, No. 7.
U3 fingers

310 Chemical Analyfis of

fingers or other moift bodies, into heated glafs flafks which
can be hermetically clofed. ;

The phofphuret of lime, when well prepared, is a com-

paét mafs of a pale reddifh brown colour inclining to choco-
late. It inflames by the leaft humidity, and emits in the
air an odour of garlic mixed with that of phofphorated hy-
drogen gas.
_ The fame phofphuret may alfo be prepared direétly from
lime, by direéting, by means of a gafometer with a column
of water, through a hole formed in the belly of the matrafs,
on the red matter, at the moment of adding the phofphorus,
a delicate current of carbonic acid gas.

L. Chemical Analyfis of an uncommon Species of Zeo-
ite. By Ropert Kennepy, M.D. F.R.S. F.A.S.,
and Member of the Royal College of Phyficians, Edin-
burgh*.

Tue zeolite fubjected to the following experiments pof=
feffes fome of the diftinguifhing properties common to other
ftones of the fame clafs, but differs in-certain refpects from
any variety with which I am acquainted. I found it, more
than three years ago, in the bafaltic rock on which the caftle
of Edinburgh is built; and it was inclofed within a mafs of
prehnite.

The colour of this zeolite is in fome parts nearly white,
in others grayifh white. It is compofed entirely of ftraight
fibres arranged in bundles or maffes of different fizes, all the
fibres of each mafs converging towards a common point.
The whole fpecimen is an aggregate of thefe maffes, the bafes
of which are in contaét with the prehnite, and are impreffed
with the form of its furface, which is rounded or botryoidal.
The crofs fraéture prefents the irregular and ragged ends of
the broken fibres, termed the ackly fra€ture by Mr. Kirwan.

Although the fhape and arrangement of the fibres appear
‘plainly to be the effects of cryftallization, yet I have not been
able to trace a perfectly regular, determinate form in any of
them. However, when the ftone is broken, fome of them
can be readily feparated Jongitudinally, in a pretty entire
‘ftate, and feem in moft inftances to be four-fided and rec-
tangular. Their length is from half an inch to two inches;
but their thicknefs does not exceed 1-4cth or 1-50th part of
aninch. None of thefe fibres can be broken acrofs, fo as to

* From the Edinburgh TranfaCtions, vol, v.
prefent

an uncommon Species of Zeolite. eo aee

.
prefent an_even furface; for they break irregularly, and be-
come divided at the point of fracture into very minute fpi-
cule, which alfo affume a fomewhat reétangular fhape.

The fmall fpicule or fibres are tranfparent and colourlefs,
with a confiderable degree of Juftre; but the unbroken part
of the ftone poffeffes lefs Inftre than the feparate f{piculz, and
much lefs tranfparency, from a want of compactnels, and
from the effect of many minute cracks. :

Its hardnefs is not eafily determined, on account of brittle-
nefs; but when a piece of it is rubbed againft ¢lafs, though
the fibres crumble down very quickly, yet the olafs is flightly
{cratched at the fame time. Small fragments of it can be
broken with the fingers, or crufhed by preflure, into very
flender fpicule, which are fharp, and apt to penetrate the
hands when touched. Although the cohefion of its compo-
nent parts be fo weak, yet it bends, and yields in fome mea-
fure before it breaks, and is not eafily ground to powder in
a mortar.

I found the fpecific gravity of different pieces of the fpeci-
men, taken in diftilled water at the temperature of 60°, to
vary from 2'643 to 2°740.

This ftone has the property of appearing luminous in a
dark place, both by friétion and by heat. A very flight de-

ree of friction produces this effeét; for a perfon can eafily
itinguith a phofphoric light, even if he draws his finger
acrofs it. When ftruck with a hammer in fuch a manner
that {mall fragments are driven off, they appear luminous in
paffing through the air, aud continue to fhine for a moment

after falling on the ground; and a hard body drawn over it

leaves a track of light, which remains a fecond or two vifible,
When a piece of the ftone is pounded quickly in a mortar, a
ftrong light is emitted; but after being wholly reduced to
powder, it no longer fhines,

The light which it gives by flight friGtion, is fully equal ta
that produced by two quartz pebbles rubbed or {truck againit
each other firongly.

Small fragments of this zeolite placed on a piece of hot
iron or of clay, allio become luminous, and {hine with nearly
as much brightnefs as common blue fluor does, when heated
in the fame manner. By being made red-hot, however, it

is deprived of the property of giving light afterwards by heat,

though it ftill appears faintly luminous by friction. In all
thefe experiments it is a reddith white light which it emits,
accompanied at times with reddifh momentary kind of fla(hes.
It san be melted without difficulty into glafs, Whena
U'4 {yall

om Chemical Analyfis of

{mall piece of it is heated gradually with the blow-pipe, it
firft becomes white and opaque; a number of fiffures are then
formed, by which its bulk appears fomewhat increafed ; and
after the flame is made fufficiently intenfe, it melts into a glo-
bule of colourlefs glafs, the tranfparency of which is imperfeét
on account of many minute air-bubbles. Although thus
fufible by ftrong heat, yet a very low degree of ignition
fcarcely affeéts it. A piece of the ftone, after having been put
inte a crucible, and expofed for a fhort time to a fire which
made it juft vifibly red-hot, was not altered in appearance,
and had not loft more than ;3,th part of its weight. Ina
temperature, however, about 20° of Wedgwood, I found that
a fragment of this zeolite became opaque, and more eafy to
pulverize than in its natural ftate; at go® it did not melt, but
was glazed on the furface, adhered to the crucible, and had
begun to fink down; and at 120° melted into an imperfect
glafs of a light greenith yellow colour, deficient in tranf-
parency, which acted ftrongly on the crucible.

In temperatures fufficiently high, it lofes from 4} to 5
per cent. of its weight; but to produce this effect, the heat
mutt be equal at leaft to 20° or 25° of Wedgwood. Part of
the volatile matter thus driven off, is carbonic acid; for the
zeolite, when reduced to powder, and mixed with acids, pro-
duces a flight effervefcence. I found, by three different ex-
periments, that the lofs of weight after the effervefcence was
about 3 per cent.; confequently, the remaining 2.or 2} parts
may be prefumed to confift of moifture.

This fubftance produces a jelly, as moft other zeolites do,
with the ftronger acids. When ground to powder, and mixed

- with the fulphuric, nitric, or muriatic acid, the mixture be-
comes a firm jelly in a few minutes, provided the acids are
not much diluted, or ufed in too great quantity. That which
is formed by the ation of the nitric or the muriatic acid, is
nearly tran{parent; but the ftone contains fo much lime, as
will prefently be fhown, that with the fulpburic the jelly is
white aud opaque, on account of the fulphate of lime which
js generated,

The prehnite in which it was inclofed, as already men-
tioned, is of a light green colour, with fome Iuftre, and
a‘confiderable degree of tranfparency. It gives fire with
fteel, can be readily melted with the blow-pipe, and froths
up much before fufion.

Having made thefe preliminary experiments refpeéting the
general pyoperties of the zeolite, I fubjeéted a partion of it, in
the next place, to analyfis, to afcertain of what earthtgit was

compofed,

an uncommon Species of Zeolite. 313

compofed, and found that it confifted almoft wholly of filex
and lime, with a certain proportion of foda. The following
were the methods by which it was analyfed :

1. One hundred grains, reduced to fine powder in a mortat
of flint, were mixed with 500 grains of muriatic acid and
1000-grains of diftilled water. The powder was immediately

attacked by the acid; fome heat and momentary effervei-

cence were produced, and in a few minutes the filex appeated
floating in a loofe and very divided ftate. The mixture being
heated on a fand-bath, became in a fhort time a thin tran{-
parent jelly. I expofed this jelly to a gentle heat (lefs than
200° of Fahrenheit) till it became nearly dry. Water was
then poured on it, and the mixture, after being digefted for
fome time, was filtered. The undiffolved part collected on
the filter, when fufficiently wafhed, was dried and heated
red-hot for a quarter of an hour. It weighed 51; grains,
was perfectly white, and proved on examination to be pure
filex, unmixed with any other earth.

2. The filtered folution, which was tranfparent and nearly
colourlefs, after being faturated with cauftic ammonia, depo-
fited afmall quantity of a brownith white precipitate. avis
colleéted this precipitate on a filter, and wathed it, I expofe
it for a few minutes to a red heat. It then weighed one gram,
and had become brown, and was found to confift of half a
grain of oxide of iron, and half a grain of argil.

3. In the next place I added a few drops of fulphuric acid
to the folution, to difcover if it contained any barytes or firon-
tian. The acid produced no precipitate. The folution was
then evaporated to a {mail quantity, and boiled with carbo-
nate of ammonia. Some carbonate of lime was thrown down,
which, after being wafhed, and expofed for a few minutes to
a very low red heat, weighed 57 grains. ‘To drive off the
carbonic acid, and afcertain the real quantity of lime which
this precipitate contained, I put it into a {mall crucible of
Cornifh clay, which was incloled within a Heffian crucible,
and heated it for three hours. The fire was raifed flowly at
firft, but was afterwards increafed to 80° of Wedgwood. The
lime adhered flightly, and weighed 317 grains. By treating
it with fulphuric acid I detected fome flight traces of mag-
nefia, the re(t being wholly converted into fulphate of lime.

4. The different earths having been thus feparated from
the folution, it was evaporated to drynefs for the purpofe of
obtaining the foda, which’I had learned by previous experl~
ments would be wholly taken up witb the other foluble parts
of the zeolite, when decompoled by acids. After the eva-

, poration

314 Chemical Analyfis of

poration a white falt remained, which was heated gradually
ma crucible to volatilize the muriate of ammonia ak im
the courfe of the analyfis. When white vapours ceafed to
rife, the heat was increafed to rednefs, and a falt was left
which weighed 17 grains. On rediffolying it in a {mall quan-
tity of water, and boiling the folution with carbonate of am-
monia, a minute portion of carbonate of lime was precipi-
tated, which weighed one grain ; equal to about half a grain
of pure lime. I obtained the falt by a fecond evaporation ;
and after it had been expofed again to a very low red heat, it
weighed 16 grains, and confifted wholly of muriate of foda.

According to Mr. Kirwan’s experiments, 16 parts of mu-
riate of foda in cryftals contain 8°5 parts of fada; but the 16
parts above mentioned, by having been dried in a red heat,
and confequently freed from water of cryftallization, would
contain fomewhat more than 8°5 parts of foda. However,
the proportion of foda in 109 parts of the zeolite may be
ftated at 85 parts, which, though probably rather lefs than
the real quantity, muft be very nearly correct.

Having finifhed the experiments juft defcribed, I analyfed
the zeolite a fecond time ; and made ufe of nitric acid, for
the purpofe of afcertaining whether any muriatic acid en-
tered into its compofition. By the teft of nitrate of filver, I
found that fome traces of the muriatic acid could be diftin-
guifhed, although the quantity was very {mall. With regard
to the proportion of the earths, the refults of the fecond
analyfis correfponded almof exactly with the former.

I alfo expofed fome of the zeolite to the aéction of the ful-
phuric acid in the following manner, with the view of ob-
taining the foda only, the earths being difregarded. One
hundred grains*, reduced to fine powder in the flint mortar,
were mixed with 250 grains of fulphuric acid, diluted with
twice its weight of water. Some heat and very flight effer-
vefcence were produced, and the mixture foon became thick
and gelatinous. It was then evaporated flowly to drynefs in
a fand-bath in a cup of Chinefe porcelain; and the dry mafs
was pulverized and boiled for half an hour with water, and
_ filtered. Having wafhed the undiffolved refiduum fufficiently,
I boiled the filtered folution with carbonate of ammonia,
which precipitated fome earthy matter. After this had been
feparated by. filtration, the folution was evaporated to drynefs

_ ® [made ufe of {mall quantities only of the zeolite in all theft experi-

ments; becaufe, as the fpecimen appears to be the on'y one of the kind

' which has been found, I wifhed to preferve as much of it entire as pot-
fible.

by

- én uncommon Species of Zeolite. 4r5

by agentle heat; atid the faline mafs left was put into acrus
ciblé, and heated flowly to rednefs. A white falt remained
in the crucible, which weighed 19 graitis. To’ free this fale
from any remains of earthy falts which might be mixed with
it, I diffolved it in a fmall quantity of water, added fome car-
bonate of ammonia, and’ boiled the mixture for a few mt-
hutes, by which means a flight earthy precipitate was thrown
down. “This being feparated as before, the falt was again
éolleéted by evaporation, and heated to rednéfs. It now
weighed 173 grains, and was found on examination to be
pure fulphate of foda *.
_ By Mr. Kirwan’s eftimation, 171 parts of dty fulpbate of
foda contain nearly eight parts of alkali ; confequently, from
Too’ parts of the zeolite there have been obtained by the pro-
cefs laft defcribed eight parts of foda. This refult corre-
fponds with the former, in which the alkali was colleéted in
the ftate of muriate of foda, as nearly as can be expected in
fuch experiments ; and it muft be remembered, that the pro-
portions of the component parts of neutral falts are not af-
certained with precifion.

According to the different experiments now detailed, roo
parts of this zeolite contain,

Silex (No. 1.) - - - 55
Lime (No. 3 and 4.) - - 32
Argil (No. 2.) .- = - ~ 5
Oxide of iron (No. 2.) - - 5
Soda, about - - - - 8:5
Carbonic acid and other volatile matter 5°

98°
with fome traces of magnefia and muriatic acid.

The ftone which has now been defcribed refembles fome
of the varieties of tremolite mentioned b Sauffure +, 1n the
property of giving a phofphoric light by A tion. Its fpecific

gravity alfo is fomewhat greater than that of the ordinary

inds of zeolite, as ftated by mineralogifis. Excepting in

thefe particulars, however, it has the principal characters of

* The experiments which fhowed that foda was the alkal'ne bafis of
thid falt, hve nor been ftated here ; becaufe I formerly gave a defeription
of the methods ufed ih examining the fatne falt, in the paper on whinftone
and lava, publithed in part 1. vol. vy. Edinb. Tranfac. To avoid unne-
ceflary repetition, I beg leave to refer to that paper, both with regard
to the manner in which I endeavoured to determine t: € purity of the faline
matter, and alfo that of the filex and fome other earths.

+ Voywges dans les Alpes, 1923. .

a zeolite ;

316 Aaion of fome lately difcovered Metals and Earths

a zeolite; for example, in its internal compofition, in having
been found in a whin rock adhering to prehnite, and in pro-
ducing a jelly with acids. Tremolites have a higher {pecific
gravity than this ftone, are more infufible, and are confider-
ably different in their compofition*. Befides, fuch kinds of
tremolite as I have examined cannot be decompofed by acids
even when boiling, and muft be heated with potath or foda
before their component parts can be feparated ; but the fub-
ftance in queftion is completely decompofed by acids, like
the greater number of zeolites, in a very few minutes, and
without the affiftance of heat. For thefe reafons it appears
to me to be a zeolite.

LI. Experiments re[peing the Ation of fome lately difcovered
Metals and Earths on the Colouring Matter of Cochineal.
By M. HERMSTAEDT fF.

To prepare the cochineal for thefe experiments, two ounces
of Mexican cochineal of the firft quality, being reduced to
fine powder, were boiled ina tin bafon with 74 ounces of
diftilled water. . The liquor was then filtered and meafured :
it had loft two ounces by evaporation. It was then divided
into portions of 2 ounces for each experiment.

A piece of kerfeymere dipped in this tin€ture when taken
out was of a lilac colour.

Exp.1. A faturated folution of very pure cobalt in nitric
acid was dropped into a portion of the tinéture of cochineal.
The tinéture became very clear, affumed a yellowifh red co-

Jour, but remained diaphanous. After twelve hours there
was depofited a precipitate of a fulphur-red colour; which,

however, was in fuch fmall quantity that it was impoffible to
colleé& it. {

Exp. II. Part of the folution of cobalt in nitric acid was
diluted with water heated to ebullition in a glafs veflel, and
kept boiling for three minutes, with a piece of kerfeymere
24 inches {quare. The kerfeymere thus prepared being then
immerfed in the warm tincture of cochineal, immediately
affumed a faturated bright red colour, leaving the tincture

* Kirwan’s Mineralogy, vol. i. p.278. Traité de Mineralogie par
Haiiy, tome iii. p. 153 and 227.
+ From Scherer’s di/gemeines Fournal der Chimie, January 1802.
cvlourlefs.

on the Colouring Matter of Cochineal. 317

colourlefs. The ftuff, after it was wafhed and dried, retained
a bright mordoré colour. . i
Exp. TIt. A neutral folution of cobalt in fulphuric acid

-was added to the tin@ture of cochineal. The tin¢ture afflumed

a darker colour, and a violet precipitate was depofited. A
piece of ftuff impregnated with this folution of cobalt, and

then dipped in tinéture of cochineal, acquired a faturated
violet colour.

Exp. 1V. A neutral fulphuric folution of uranium gave
with tin@ture of cochineal a precipitate almoft black; but
when a piece of ftuff was dipped in the fame folution, and
then dyed with tincture of cochineal, it aflumed a very agree-
able grayifh colour inclining to green, 4

Exp. V. A folution of cobalt in nitric acid, treated in the
fame manner, gave the fame refults; but with this difter-
ence, that the colour on the fluff was a little brighter.

Exp. VI. Fifteen grains of tungftic acid were put intoa
glafs veffel, and fix ounces of diftilled water being poured
over it, the whole was reduced by evaporation to four ounces.
The folution affumed a turbid afpeét, and a blueifh white
colour. A part of this folution being poured into tincture
of cochineal, communicated to it a bright violet colour. A
piece of kerfeymere, being boiled for three minutes in this
folution, was immerfed in the warm tinéture of cochineal :
when taken out it was of a bright ponceau (poppy) colour.

Exp. VII. Fifteen grains of concrete molybdic acid were
diffolved in water as above. It diffolved entirely, and the
folution became clear and tranfparent.. Being dropped into
the tincture of cochineal, a dark violet precipitate was ob-
tained. A piece of kerfeymere boiled in the acid folution
affumed a colour approaching to bright green, which, when
the fiuff was dried in the fun, paffed to a gray inclining to
bright blue. A piece of kerfeymere impregnated with the
fame folution,. being immerfed in warm tincture of cochi-
neal, affumed a very agreeable violet colour. — ;

Exp. VIII. Arfenic acid, being mixed with the tinéture
of cochineal, the dark red colour of the latter was transformed
into yellowifh red, but without ar depofit being formed.
A piece of kerfeymere was then boiled for three minutes In
a very dilute folution of the fame acid, and the ftuff thus
prepared was immerfed in warm-tinéture of cochineal. The
ftuff immediately affumed a bright fcarlet colour inclining
ftrongly to yellow, Drying, and, in particular, prettng with

' a hot iron, made this colour lofe a little of its brightnels, and

caufed it to ate darker. Exp. IX.

g18 AGionof fome lately difcovered Metals and Earths

Exp, 1X. A folution of arfeniate of foda flightly acidu-
lated was applied as a mordant to another piece of kerfey-
mere, and by immerfion in tinéture of cochineal a dark
gordoré colour was obtained. .

Exp. X. The fame was repeated with alkaline arfeniate of
foda: an agreeable lilac was obtained.

Exp. XI. Common white arfenic diffolved in water, gave
a lilac colour fomewhat dark.

Though the.author intended, only to try the a€tion of the
metals lately difeovered on the colouring matter of cochineal,
tefults before obtained from lead induced him to fubjeét this
metal alfo to fome new trials. He undertook at the fame time
to afcertain how far the ufe of nitrate of tin is indifpenfably
neceflary in dyeing common fcarlet, by endeavouring to fub»
ftitute for that falt muriate of the fame metal. Thefe re-
fearches gave rife to the following experiments :

Exp. XU. A folution of acetite of lead being poured into
_tinéture of cochineal, a violet blue precipitate was formed.
A piece of kerfeymere prepared with acetite of lead was then
immerfed in the fame tin€ture, and a very agreeable violet
colour was obtained. :

Ey. XIIL. A folution of fine Englith tin in pure muriatic
acid was expofed for four weeks in an open veffel to the.ac-
tion of the air. A piece of kerfeymere being boiled in this
folution, and then immerfed in warm tincture of cochineal,
it afflumed a bright {carlet colour.

This refult is the more remarkable, as it has hitherto been
believed that it was impoffible to dye fcarlet without a folu-
tion of tin in aqua-regia; and indeed the red obtained by
employing. common, muriate of tin inclines to violet. It ap-
pears, therefore, that the oxygen of the nitric acid brightens
the colour. As thefame {tate of oxidation may be communi-
cated to muriate of tin by expofure to the air as.by nitric
acid, the expenfe occafioned by the ufe of this acid and
that of fal-ammoniac may be fpared by fubftituting muriatic
acid, whichis much cheaper.

Exp, X1V. A piece of kerfeymere was boiled for three
minutes 1n a neutral folution of muriate of barytes, and then
ammerfed in tincture of cochineal. The ftuff affumed a dark
colour, which, after being wafhed and dried, changed to an
agreeable violet. :

Exp. XV. Nitrate of barytes employed as a mordant gave
a poncean red exceedingly agreeable.

£1p. XVI. Acetite of barytes tried for the fame purpofe,
gave

on the Colouring Matter of @ochimeal, 319

er adark red ponceau; which, however, pofleffed great —
rightnefs. ; ;

Exp. XVII. A’piece of kerfeymere was dipped for three
minutes in a folution of muriate of ftrontian, and then im-
merfed in a bath of cochineal. It affumed a dark colour;
which at firft imitated that of fearlet, but which by drying
paffed to crimfon.

Ew. XVII. A neutral folution of nitrate of ftrontian
produced a bright reddifh brown, ’

Exp. XIX. Acetite of ftrontian produced a bright pone
eau,

The refults of thefe experiments prove, not only that the
metals and earths fubjected to trial poffefs a certain chemical
affinity for the colouring matter of cochineal, and are capable
of fixing it on ftuffs, but that they poffefs alfo the property
of producing with the fame pigment very different fhades.
They prove befides, that the nature of the acid, which ferves
as a folvent to thefe fubftances, exercifes a great influence
on the fhades produced.

The refults obtained with the oxide of arfenic and the acid
of that metal, are no Jefs worthy of attention. The difference
of the colours produced is particularly remarkable. The oxy-
gen, no doubt, had the greate(t {hare in this phamomenon,
as this principle manifefts, in a very evident manner, its
great influence in the production of fearlet by the muriate of
tin oxidated by the air.

;

:
:
LIL. On the Manner of Hunting and Sporting by the Englifb
in Bengal. . Communicated by Colonel G. [RONSIDE™. °
|

Few parties of pleafure can be more agreeable’ than thofe
for hunting, formed by ladies and gentlemen in Bengal, par-
‘ticularly at fome diftance from the‘ prefidency of Fort: Wil-
liam, where the country is pleafanter, ‘and game of every
kind in greater plenty. Any time between the beginning ot
November and end of February is taken for thefe excur-
| fions; during which feafon the climate is delightfully tem-
onan the air perfe@lly ferene, and the fky often without a

cloud.

To tranfport the tents and other requifites, for the accont-

ab.
niogaee>
YT ot,

By

* From the Aiea Annual Regifler Jur 1801

320 On the Ma@hod of Hunting and Sporting

modation of the company, to fome verdant fpot, near to a
grove and rivulet, previoufly felécted, elephants and camels
are borrowed ; {mall country carts, oxen, and bearers hired,
at no confiderable expenfe, the price of all kinds of grain,
and wages of courfe, being exccedingly reafonable. Nor does
the conmmanding officer of the troops within the diftrié often
refufe a guard of fepoys to protect the company from the
danger of wild beafts, (for fuch generally refort to the haunts
of eame,) or the depredations of {till wilder banditti, now and
then pervading the country. :

The larger tents are pitched in a fquare or circle, while
thofe for the guards and fervants ufually occupy the outer
fpace. Every marquée for a lady is divided into two or three
apartments, for her camp-bed, her clofet, and her dreffing-
room; is carpeted or matted, and is covered with a {preading
fly, for defence againft rain, or exclufion of cafual heat, the
air ventilaung powerfully between the vacuity (about two
feet) of the tent and its canopy in unremitted undulation.
The doors or curtains of the marquée, wattled with a fweet-
feented grafs, are, if the weather chance to become fultry,
continually fprinkled with water from the outfide; and a
chintz wall, {tained in handtormely-figured compartments,
encompaffes the whole.

For the fupply of common food, if no village be very near,
petty chandler fhops enow are engaged by the family banyans
(houfe ftewards) to accompany them, glad to profit of fuch

dortunity of gain. Liquors and every fpecies of Euro-
SH ptcles are provided by the party themfelves.

Horfes are employed for the conveyance of the gentlemen,
and palanquins for the ladies, with. their female attendants;
and, where the roads will admit of it, clofe and open Englifh
carriages alfo, BG

Part of the morning fpaorts of the men, commencing at
dawn of day, confift in roufing and chafing the wild boar,
the wolf, and antelope (or gazelle), the roebuck, the mutk,
the red and other deer, hares, foxes, and jackalls: betides
the common red, the fpotted and the fmall moofe, there are

ten or twelve forts of hog or fhort-briftled deer. Boars,are
ufually found amongft the uncultivated tracts, or the more
regular plantations of fugar-canes, which give to their fleth
othe fineft flavour imaginable. Wolves and jackalls are feen
rowling and lurking, at break of day, about the fkirts of
ii. and villages, or retiring from thence to their dens

t within woods; or within pits, hollows, or ravines, on the

eet - Hares fhelter ig the faine fituations as in England.
a ; ; Uhe
ie

Sah

by the Englifh in Bengal. 321

The hog, roebuck, and mufk deer, conceal themfelves amongft
the thickeft heath and herbage, and the antelope and large
deer rove on the plains. All thefe animals, however, refort
not rarely to the jungles (or very high coarfe and implicated
grafs), with which the levels of Hinduttan abound, either to
gtaze, to browfe, or in purfuit of prey.

A country of Afia abounding in fuch variety of game, is,
of courfe, not deftitute of wild beafts; the principal of which
are the tiger, leopard, panther, tiger cats, bear, wolf, jackall,
fox, hyzena, and rhinoceros. The leopards are of three or
four kinds.

Or the gentlemen divert themfelves with fhooting the fame
animals; as alfo common partridge, rock partridge, hurrial
or green pigeons, quail, plover, wild cocks and hens, eur-
Jews; black, white, and gray peacocks; florikens, ftorks of
feveral kinds and colours, together with water hens, Bra-
miny geefe, cranes, wild geefe and ducks, teal, widgeons,
Tnipes, and other aquatic fowl, in infinite abundance; many
of them of extraordinary fhape, of glowing variegated plu-
mage, and of unknown fpecies; whofe numbers almoft cover
the water whilft they fwim, and, when alarmed, and flufhed
from the lakes, like a cloud, abfolutely obfcure the light.

The foxes are fmall, flenderly limbed, delicately furred
with a foft brown hair, and by no means rank in fmell;
fecding principally upon grain, vegetables, and fruit. They
are exceedingly fleet and flexible, though not ftrong or per-
fevering. When running, they wind in fucceffive evolutions
to efcape their purfuers, and afford excellent fport. Their
Aholes are ufually excavated, not in woods, but on hillocks,
upon a fmooth green {ward or lawn, where, in a morning or
evening, they are feen playing and frifking about with their
young. They feed generally amongg the corn, and are often-
eft found within ficlds of muftard or linfeed, when it has
fprouted up high enough to conceal them.

A minor critic, on perafal of Aufop’s or rather Pilpay’s
fables, ridiculed the idéa of foxes feeding upon grapes ; but,
had he confulted any Afiatic natural hiftory, he would have
learnt that they fubfift upon grain, pulfe, and fruit, particularly
grapes and pine-apples when within their range, much more
than upon fleth or fow]. Or, had he turned to the Bible, he
would have there found the following paffage in confirmation
of it:—*“* Take us the foxes, the little foxes, that fpoil the
vines, for our vines have tender grapes.””—Canticles, c. ti.
ver.

Jackalls are rather larger than, Englith foxes; but of @

OL AIV. No. 560° XG brown

32% On the Manner of Hunting and Sporting

brown colour, clumfier fhape, and not fo pointed about the
nofe. In nature, they partake more of the wolf than of the
dog or fox, Their real Afiatic name is fhugaul, perverted
by Englith feamen trading to the Levant ¢where they are in
plenty on the coafts of Syria and Afia Minor) into jackalls,

Of the partridge there are feveral kinds, one with a white
belly, and another fomething like groufe, only more motley
feathered.

Plover too are various; and, when the weather becomes
warm, ortolans traverfe the heaths and commons in immenfe
flocks.

There are no pheafants in the woods of Bengal or Bahar
nearer than the confines of Aflam, Chittagong, and the range
of mountains feparating Hindu(tan from Tibet and Napaul.
But there, particularly about the Morung and in Betiah,
they are large and beautiful, more efpecially the golden, the
_burnifhed, the fpotted, and the azure, as well as the brown
Argus pheafant. é

As for peacocks, they are every where in multitudes, and
of two or three fpecies. One tract in Oriffa is denominated
More-bunje, or the Peacock Diftrict,

Cranes are of three forts, and all of a czrulean gray: the
yery lofty one, with a crimfon head, called /arus; the fmall-
eft, called curcurrab, (the demoi/elle of Linneus and Buffon,)

‘uncommonly beautiful and elegant, whofe fnow-white tuft,
behind its fearlet-glowing eyes, is the appropriate ornament
for the turban of the emperor alone; and the middle-fized
one with a black head, the common grus. They return to
the northern mountains about the autumnal equinox, after
ceffation of the periodical rains, with their young, in myriads
of flights, frequent as the wood pigeon in North America;
and fometimes, when the*wind is very violent, flocks of them
mount to a vafi height in the air, and there wind about in
regular circles, feemingly with much delight, and venting
ali the time a harfh difcordant feream, heard at a confiderable
diftance.

In the wilds of Hindufan certainly originated the common
domeftic fowl, for there they are difcovered in almoft every
foreft. They are ali bantams, but without feathers on their
legs ; the cocks are in colour ajl alike, what fportfmen call
ginger red; they have a fine tufted clutter of white downy.
feathers upon their rumps, are wonderfully ftately in their
gait, and fight like furies. The hens are invariably brown.
It is extremely pleafant, in travelling through the woods early
in a morning, to hear them crowing, and to perceive the

‘4 hens

q

by the Englifh in Bengal. 323

hens and chickens fkulking and feudding between the buthes.
food, they are neither fo palatable nor tender as the tame
owl,

Florekins are amongit the mon defcripta, I believe, in or-
nithology. A drawing can alone exhibit an adequate repre-
fentation of this fine bird; it harbours in natural paftures
amongft the long grafs, on the extremity of lakes, and the
borders of fwampy grounds, lying between marfhy foils and
the uplands. Hence its flefh feems to partake, in colour and
relifh, of the nature and flavour of both the wild duck and
the pheafant; the colour of the flefh on the breaft and wing
being brown, but on the legs perfectly white, and the whole
of the moft delicate, juicy, and favoury flavour conceivable.

There are only three claws to its feet; the roots of the fea-
thers of the female are of a fine pink colour.

When the cock rifes up, fome fine black velvet feathers,
which commonly lie fmooth upon his head, then ftand up
ereét, and form a tuft upon his crown and his neck.

When fet by dogs, it lies clofe, and fcarcely ever rifes till
the fowler is fo near as almoft to tread upon it. The neft of
it is made amongfi the grafs.

You read of them in defcriptions of antient knightly fefti-
vals of the Nevilles, Percys, Mortimers, Beauchamps, Mon-
tacutes, De Courceys, Mohuns, Courtenays, and Mowbrays,
under the name, I believe, of flaaderkins; but whether they
were then native of England, [ am uncertain.

The height of the cock florekin of Bengal, from the ground,
when he ftands, to the top of his back, is feventeen inches.

The height from the ground to the top of his head, when
he holds it upright, is twenty-feven meches.

The length from the tip of his back to the end of his tail,
is twenty-feven inches.

In no part of fouthern Afia did I ever hear of woodcocks ;
but amongft the breed of fnipes there is one called the painted
fnipe, larger than ordinary, and which well compenfates for
want of the former.

Fifhing, both with lines and diverfity of nets, is the em-
ployment of other fets of the party; or the hawking of he-
rons, cranes, ftorks, and hares, with the falcon; and of par-
tridge and leffer birds, with the fparrow and fmall hawks.

Ladies now and then attend the early field : ifat be to view
the courfing or hawking, they mount upon {mall gentle(t (for
they are all gentle) female elephants, farmounted with arched-
canopied and curtained feats; otherwife they ride on horfe-
back; more frequently however in palanquins, under which,
as well 43 under the elephants and hortes, the birds, (parti-

X2 cularly

324 On the Manner of Hunting and Sporting

cularly the white ftork or paddy bird,) when pounced at by
the hawks, and the little foxes, when hard preffed by the
dogs, often fly for fhelter and protection. In general, how-
ever, the ladies do not rife betimes, nor ftir out till the hour
of airing. ”

The weapons in ufe on thefe expeditions are, fowling-
pieces, horfe piftols, light lances or pikes, and heavy {pears
or javelins; and every perfon has, befides, a fervant armed
with a feymitar or fabre, and a rifle with a bayonet, carrying
a two-ounce ball, in the event of meeting with tigers, hyz-
nas, bears, or wild buffaloes. Some of the ladies (like Tha-
leftris or Hypolita, quite in the Diana ftyle,) carry light bows
and quivers to amufe themfelves with the leffer game.

_ The dogs are, pointers, fpaniels, Perfian and European

_ greyhounds, and firong feroctous lurchers. | Near Calcutta a
few gentlemen keep Englith hounds; but their fcent quickly
fades, and they foon degenerate.

But the livelieft {port is exhibited when all the horfemen,
elephants, fervants, guard, and hired villagers, are aflembled
and arranged in one even row, with fmall white flags (as
being feen furtheft) hoifted pretty high at certain diftances,
in order to prevent one part of the rank from advancing be-
fore the reft. Proceeding in this manner, in a regular and
progreffive courfe, this line {weeps the furface like a net, and
impels before it all the game within its compafs and extent.
When the jungle and coppice chance to open upon a plain,
it is a moft exhilarating fight to behold the quantity and va-

‘riety of animals iffuing at once from their coverts: fome aré

driven out reluétantly, others force their way back into the
brake. During this fcene of development, rout, and di-
fperfion, prodigious havock is made by the fowlers, falcon-
ers, and huntfmen, whil{t the country people and children,
with {ticks and ftaves, either catch or demolifh the fawns,
leverets, wild pigs, and other young animals, which have
returned into the coppice.

Inftances occafionally occur, where the natives of the vi-
cinage petition the gentlemen to-deftroy a tiger that has in-
felted the diftrit, to the annoyance and devaftation of their
flocks and fhepherds, and perpetual alarm of the poor cot-
tagers themfelves. Although an ‘arduous and perilous adven-
ture, and what the gentlemen all profefs, in their cooler mo-
ments, to reprobate and decline, yet, when in the field, they
generally comply with the folicitation, and undertake the ex-
ploit. ‘Their inftant animation, not unattended with emo-
tions of benevolence and compafiion, prefently fuperfedes every
dictate of prudence, and, fpite of their predetermination, they

proceed

oe

by the Englifh in Bengal. 325

proceed to the affault, the villagers all the while ftanding
aloof. If conduéed deliberately, with circumfpection, and
with the aid of the fepoys, they foon accomplifh their pur-
pofe, and bring in the moft dreadful and formidable of all
tremendous beafts, amid{t the homage and acclamations of
the peafantry.. But fhould they lofe their prefence of mind,
prolong or precipitate the conflict, aét with incaution, or at-
tack the exafperated infuriated favage with tumult and con-
fufion, the event is often fatal, by his feizing, lacerating, and
erufhing, every creature within his reach ; nor ceafing to rend,
tear, claw, and deftroy, to the very moment of his deftruction,
or of his flight.

Sometimes do the natives entreat the gentlemen to rid
them of wild buffaloes, (the largeft of all known animals, the
elephant excepted,) that have laid wafte their cultivation ;
and at others, to clear their vaft tanks, or {mall neighbouring
lakes, of alligators, which devour their fith, or do mifchief on
fhore. So much hazard is not incurred, however, by achieve-
ments of this fort, as from the encounter of a tiger; for though
the hides of thofe creatures refift a balk from a firelock at
common mufket diftance, they are by no. means impenetra-
ble to fhot from a rifle, or other pieces with a chamber, or of
a wider calibre. ,

A drum, with a banner difplayed from the hall-tent, gives
fignals to the company for their meals.

Breakfaft is a moft delightful repatt: the fportfmen return
keen, frefh, ruddy, and voracious: and the appearance of the
ladies in fimple loofe attire, the elegant difhabille of cleareft
muflin with plain floating ribbons, and difhevelled treffes,
captivate to fafcination. Nor is the palate lefs gratified +
Englith, French, Italian, and Dutch viands, all combine to
provoke it, by a profufion of cold vigtuals, falted and dried
meats and fifh, hams, tongues, faufages, hung-beef, fallads,
chocolate, coffee, tea, freth milk, preferves, fruit, and eaes,
rendered {till more grateful by the moft {prightly cheerfulnefs
and Auroral gaiety.

After breakfaft, conveyances of different forts are prepared
for an airing, not merely for the fakejof airing only, but to
view fome natural or artificial curiofity or manufacture ; fome
noted town, diftinguifhed mofque, celebrated pagoda, re-
nowned dirgah, or venerable maufoleum’; fome confecrated
grove, the fequeftered refidence of fakeérs, or fome extenfive
profpect from the fummit of rugged cliffs, impending over
an expanfe of water, bordering perhaps a level lawn, whole
verduire is vaulted only, not concealed, ly a diffufed affem-
blage of ftately colurnniated. palms af four different {pecics,

X3 tufted

326 On the Manner of Hunting and Sporting

tufted and foliaged only, in graceful inclinations at their ca-
itals, all equally ornamental, the date, the cocoa-nut, the
eau and the palmyra.

Between the airing and an early dinner, the hours are ir-
regularly difpofed, as chance may dictate, or caprice fuggeft.
Some play at cricket and quoits, fwim, jump, fence, runa
match of horfes, or fhoot at a mark; whilft others direét the
mountaineers and woodmen (who rove about in bands for
this exprefs purpofe) where to inveigle, entangle, or kill
beafis, birds, fifh, and fnakes, for which they are furnifhed
with variety of implements, fuch as matchlocks, tiger- bows,
fpears, darts in grooves, balls in tubes, pellet-bows, limed
rods, ftakes, and bufhes; fafcinating allurements, fuch as
painted, fpotted, and foliaged fcreens, bells, mets, and
torches, bundles of twigs, rufhes, and reeds, artificial ducks
and decoy birds, with traps, gins, fprings, fnares, and other
ftratagems and inventions of wonderful enchantment, imge-
nuity, mechanifm, and contrivance.

It is fomewhat extraordinary, but neverthelefs a fact, the
influence of fafcination poffefled by the tiger, and all of his,
(the feline) fpecies, over many other creatures. *Spied by deer
particularly, they {top at once, as if ftruck by a fpell, while
the tiger lies flill, his eyes fixed on them, and quietly await-
ing their approach, which they feldom fail to make gradually
within his fpring; for the large royal tiger cannot run fpeed-
ily or far. The glow of their eyes is fierce and powerful,
I myfelf once pafled a royal tiger in the night near a wood,
and could plainly perceive the fcintillations from his eyes.
He was deterred from approaching us by the light of flam-
beaux, and the noife of a fmall drum which we carried, and
was beat by a fervant for the purpofe of fearing him away.

Wherever tigers roam or couch, a number of birds conti-
nually colleé or hover about them, fcreaming and crying as
if to create an alarm. But the peacock feems ‘to be particu-
Jarly allured by him; for the infiant a flock of pea-fow! per-
ceive him, they advance towards him direétly, and begin
ftrutting round him with wings fluttering, quivering feathers,
and briftling and expanded tails. Of this enticement the
fowlers alfo make their advantage ; for, by painting a brown
cloth fcreen, about fix feet fquare, with black fpots or flreaks,
and advancing under its cover fronting the fun, the birds
either approach towards them, or fuffer them to fteal near
enough to be fure of their mark, by a hole left in the canvas
for ibem to fire through.

Several other inftances of the fafcination of animals I have
myfelf been witnels to ise Bengal, Three or four times, —

a line

by the Englifb in Bengal. 327

a line of troops were marching in a long uninterrupted feries,
paffed a herd of deer; I obferved that when their attention
was taken off from grazing, by the humming murmuring
noife proceeding from the troops in paffing, they at firft and
for a while ftood ftaring and aghaft, as if attracted by the
fucceffive progreffion of the files, all clothed in red. At
length, however, the leading ftag, ‘ vir gregts ip/e,”’ firikin
the ground, fnorted, and immediately rufhed forward rte
the ranks, followed by the whole collection, to the utter dif-
may and confufion of the foldiery: thus running into the
very danger one naturally fuppofes they muft have at firft
been anxious to avoid. The men, who were apprifed by the
found of their approach, ftopped, and made way for them.
Over the heads of the others, who were heedlefs and inatten-
tive, they bounded with wonderful agility, and fled over the
plain.

Driving one evening along the road in a phaéton, and
pretty falt, I perceived a young heifer running near the car-
riage, with her eyes intently fixed upon one of the hind
wheels ; by the whirling of which the animal feemed com-
pletely firuck and affected. Thus purfuing her object for
about a quarter of a mile, fhe, by a fudden impulfe, rapidly
darted forward towards the wheel, which then ftriking her
nofe, the attention of the creature became interrupted by the
violence of the friction, and was, of courfe, withdrawn: fhe
then immediately ftood ftock full, and prefently after turned
about flowly and made off.

Beyond all other animals, however, ferpents poffefs moft
eminently this occult power: frequently are they feen re-

volved on the branches of trees, or on the ground, meditating
their prey, either birds, fquirrels, rats, mice, bats, frogs,
hares, or other animals.

The ladies, as they are inclined, either read, walk, fwing,
exercife thensfelves in archery, or at fhnttlecock in the groves;
or they fing and play in their tents. Others, whilft at work,
are read to by their companions; of all amufements, perhaps,
the moft delectable, *

At the end of a convivial dinner, every foul, provided the
weather prove fultry, or they find themfelves fatigued, retires
to repofe,

On rifing from this fiefta, (of all liftlefs indulgences the moft
foothing, comfortable, and refre(bing, and certainly moft
wholefome, all aniinals inclining to fleep after nourifhment,)
carriages are again in readincls, or light boats where a ftream
or lake is near, to give the company the-evening’s refpiration,

X4 (which

328 Obfervatisns upon the Monfoons.

(which the inhabitants of colder regions tafte only in poetical
defcription,) breathing health as well as recreation.

The twilight being ihort under the tropics, the day, of
courfe, fhuts in prefently after fun-fet, when cards and dice

become part of the evening’s entertainment. Chefs, back=

gammon, whift, picquet, tredrille, quinze, and loo, are the
favourite games. Thefe, with domettic fports, antics, gam-
bols, tricks, pranks, and frolics, where the humour prevails ;
together with the flights of jugelers, feats of tumblers, (in
which performances the Hindus are expert adepts,) and
dances of the natives, wile away the time, and beguile it not
unpleafantly to the hour of fupper, the principal meal; when
a repaft, enlivened by every elevation of {pirit and kindly dif-
pofition that can conduce to promote good humour and feftive
hilarity, terminates the day.

Thefe parties generally continue, with fome variation in
the amufements, fifteen or twenty days; and the diffolution
of them is as generally lamented, with heart-felt regret, by
the individuals who compofe them.

—

LIII. Od/ervations upon the Monfoons, as far as they regard
the Commerce and Navigation of the Port of Bombay *.

Our readers will not require to be told that our year is
divided into two grand feafons, or, as they are called, the
fouth-weft and north-eaft monfoon; that the firft generally
prevails from May to the middle of September inclufive, the
other during the remaining months; yet we muft premife
this as an introduétion of what follows.

We need fearcely to obferve, that during the fouth-weft
mionfoon all the ports and roadfteads on this fide of India
deny approach; fo much fo, that between the 15th of
May and the 1ft of September fhips are precluded by their
policies from touching upon the Malabar coaft, or from lying
in Surat roads between the 1ft of May and the i ft of Sep-
tember. Generally fpeaking, the monfoon is confidered to
extend from Dunder-head, the fouthern extremity of Ceylon,
to the Perfian Gulf; in order to attain which, they who
fhould fail at this feafon would be obliged to make what is
called a fouthern paflage, tbat is, go firit to the fouth of the
equator before they could firetch over to the weflward; a
voyage that would occupy, for Mufcat about forty days, and

* From the Afiatic Annual Regifler for 1802.
te
8

Obfervations ‘upon the Monfoons. 329

to Bafforah about two months. The fame objeétion exifts
againft failing at this feafon to any part of the Arabian coatt.
As for the Red Sea, it is confidered in vain to’attempt enter-
ing it at this feafon; nor can it be faid to be favourable to
fail now to the Cape, the Mauritius, or any port to the wefts
ward.

To the other fide of India, on the contrary, it is now the
mott advantageous period of departing. From the middle‘of
April, even to the middle of Auguft, a voyage to Madras may
be made in about 12 or 15 days; to Bengal from 15 to 20
days: after this time it becomes exceflively tedious, from the
neceffity of keeping to the eaftern fide of the bay, to avoid
the violent weather on the Coromandel coaft. For the fame
reafon the fouth-weft monfoon is eligible to leave Bombay
for any. of the ports in the Gulf of Bengal or the Streights of
Malacca; hence alfo it is the feafon for failing to China:
after the 20th of Auguft, however, what is called the direét
paflage to China becomes very precarious, with much pro-
bability of finding blowing weather in the Chinefe feas.

With regard to the ports from which fhips maybe expected

to arrive at Bombay during this monfoon, it may be laid’
down as a general ples that the quarters favourable to {ail to
during any feafon, ‘are thofe that it‘is unfavourable to expeét
arrivals from, and vice verfa: hence from the Perfian Gulf,
.the Red Sea, the Cape of Good Hope, -and the weftward in
general, this is the moft feafonable period to expect arrivals :
from Mufeat a trip may now be made in 10 or 12 days, from
Mocha in 20 days, and Suez in abdut a month. It fhould
be remarked, that after September the Red Sea admits of no
egrefs ; fhips confequently remaining there beyond that time,
mutt continue there all the north-eaft monfoon, and are faid
to have loft their paffage: on this account, the 25th of Au-
gut is the lateft day to which our cruifers are allowed to re-
main at Suez. From the Capea paflage may be made in
five or fix weeks; from the Mauritius, in three weeks or a
month,

The fouth-weft monfoon is alfo the moft favourable feafon
in which a paffage may be made from Batavia or any ports

to the eafiward through thefe fouthern ftreights: from Ba-
tavia to Bombay, in particular, a paflage may be made in
about 35 days. From Madras and Bengal, during the fouth-
welt monfoon, it is neceflary tomake the fouthern paflage
in order to reach Bombay: this will require, in a paflage
from Madras, from 30 to 40 days,’and from Bengal from
45 to 60 days, from the neceffity of working out of the river,
and beating down the bay to clear Acheen Head. From the

Streights

$30 Obfervations upon the Monfaons.

Streights.of Malacca it is an arduous tafk to fail for this port,
or even to any one on the peninfula of India, owing to the
difficulty of working round Acheen Head.

We have now to treat of the north-eait monfoon, or the
feafon which may be confidered as included between the 15th
of Auguft and the 15th of April; in which the firft circum-
fiance that occurs to us to remark is, that our coaft is ren-
dered in a peculiar manner fecure and favourable to naviga-
tion ; it is now confidcred the molt eligible period for {ailing
to the Perfian Guif, and in general to all poris to the weft-
ward. To Mufcat the trip is generally 15, and to Buflorah
28 days. The time fuitable for failing to Mocha and Suez
is from the middle of February to the middle of March, when
a paflage may be made to the firft in 18 days, to the fecond
in 25. Ifa thip be delayed till the latter end of March or the
beginning of April, the paffage becomes more tedious, bein
then obliged to. make the land to the fouthward of the ifland
of Socatra before the gulf can be entered, on account of the
foutherly winds which prevail, and a current fetting to the
northward. After the 15th of April, a thip bound to the
Red Sea would be very likely to lofe her paflage.

Between the 15th of Auguft and the 15th of September it

may be confidered favourable to fail to Madras and Bengal ;
but after this time the feafon is fufpended, owing to the fet-
ting in of the north-eaft monfoon on the other fide of India,
which clofes the ports on the coaft of Coromandel, Gol-
conda, and Orifla, between the 15th of O&ober and the 15th
of December; at leaftthis period is excepted in common
policies of infurance. After this time, again, a paflage may
be made to Madras in 30, and Bengal in 50 days. This
feafon may be deemed unfavourable to the coafl of Pegue .
and the Streights of Malacca; but for tbe Streights of Sunda,
Batavia for example, it is the beft adapted—a paflage thither
may be made in 35 days.
_ With regard to the feafonable imports in this monfoon, it
is at no time more advantageous than now for coming from
the Coromandel coaft, and, in thort, the whole bay: a paf-
fage may be madejfrom Madras in 20 days, from Bengal in
a month, and Penang a month. From the Perfian Gulf it is
no lefs favourable, the paffige from: Mufcat:being about. ten
days; and from Bufforah 28. The Red Sea is now clofed ;
nor is it reafonable to expeét arrivals from the Cape or the
Streights of Sunda; from the latter, in. particular, it is almott
impoffible at-this {eafon to make a tolerable patlage.

LIV. Me.

{ 331 }

LIV. Method of obtaining inodorous Benzoic Acid. By
M. F. Gizse*.

Tue benzoic acid, fuch as we obtain it in the dry or
humid way, always retains a peculiar ftrong agreeable odour,
which has hitherto been confidered as a particular character
of this acid. The numerous experiments I have made on
this acid fhow that chemifts in this refpeét have been in
an error, and that the benzoic acid may be deprived of all its
odour without injuring its principles or altering its nature.

I was led to this obfervation by remarking, that the fame
acid extraéted from the urine of graminovorous animals,
when deprived of all urinous odour, is perfectly incdorous.
This circumftance induced me to believe that the odour of
the benzoic acid might be foreign to it; and to afcertain this
fact I made the following experiments : .

I united odorous benzoic acid to a folution of potafh, and
then precipitated by muriatic acid. On each repetition’ of the
experiment the odour was fenfibly diminifhed, and after the
third it had totally difappeared.

As the acid retained all its characters, this feems to prove
that in thefe operations it had experienced no particular mo-
dificationf. This refult, was previoufly indicated by its ace
quiring, in the progrefs of the experiment, the odour of ben-
zoic acid obtained in the humid way, which is much weaker
than that of the fame acid obtained by fublimation.

I afterwards invented another method, more direét and
lefs troublefome, for depriving this acid of its odour. It is
founded on the greater folubility of the benzoic acid in fpirit
of wine than in water; and on the folubility of the benzoic
oil, which is the principle of its-odour, in diluted fpirit of
wine. This method is as follows:

Diffolve benzotc acid in as fmall a quantity as poffible of
fpirit of wine: filter the folution, and drop water into it until
no more precipitate is formed, or until the precipitate formed
begins to be rediffolved. Separate the liquor by filtration,
and dry the acid, which remains on the filter, at a gentle
heat.

* From Scherer’s Allgemeines Yournal der Chimie, February and March
1802.

t Ucan certify that a {pecimen of this :acid, fhown to me by the au-
thor, was abfolutely free from odour. L requefted M. Giefe to fubject the
inodorous acid to fublimation, in order to afcertain whether a decompofi-
tion experienced by the heat was not the caufe of its odour. He complied
with my requeft; but he obferved no alteration in the acid, nor had it re-
fumed its odour,—ScHerer,

I fhall

332 On the Mamihoth.

I fhall here add, that having faturated the benzoic acid
with lime, and deconipofed the benzoate thence refulting by
the muriatic acid, I obtained an acid without odour; and
that M. Richter obtained the fame inodorous. acid by decom=
pots the benzoate of potath by ‘acetite of lead, and then the

yenzoate of that metal by the fulphuric acid : but of all thefe
methods that by fpirit of wine is to be preferred.

LY. On the Mammoth,’ By Governor POWNALL,

To Mr. Tilloch.
SIR,_ (2 ; 36)

-# READ, at Bath, the account which the Philofophical
Magazine, publifled by you, gave the public of the mam-
moth. In my way from Bath'to this place, I continued a
few days in London; I went twice to fee the fkeleton’ of this
enormous aninral: the firft time to take a general view of its
and fome days after, when [ had fully reafoned in my recol-
je&tion on the general conftruétion of it, I went a fecond
time to examine it in detail, «as far as my fuperficial know-
ledge in comparative anatomy would enable me.

I fhall not in this letter go over all the parts to which I
gave my attention, bui notice only thofe parts on which fome
‘doubts remained with thofe who had not feen it, and which,
‘rightly underftood, lead'to fome probable conjectures as ta
the mode and time of its exiftence in Jife. Iam, Sir,

Your moft obedient humble fervant,

Everton Houfe, ; J. POWNALL,
Jan. 1, 1803.

DOUBTS were made as to ribs being fet edgeways, fo
different from all other animals of our earth ; yet fuch is the
fact, as appears not only from’ the infertion of their heads,
bat from their curvature; alfo from their fides, wherein is
the groove into which the cartilages, by which they are con-
neéted, were inferted. | Thefe ribs appear to be of the fame
form and to be in the fame pofition as the ribs‘of fifhes, and
fo defigned for the fame purpofe, to refift an external com-
preflure of more weight and force than the preffure of the
atmofphere.

The printed: defeription’ left: it totally undecided whether
this animal had hoofs or'toes. On examining the fetting on
of the foot, it appears that it hath the eight ufual bones, in
two rows, four in each row, in the carpus, which all animals
having digits or toes have: and it hath five toes, whereon,

as

a".

On the Mammoth. 333

ae appears from the form of the end-bones, it had nails, not
claws.

The pofition given to the tufks feemed doubtful ; but, on
a view of the faét, itis decifive that they could not have been
placed otherwife. They are of a fpiral curvature of one
guarter turn: they are fo inferted into the head as to go back
alongfide the fhoulders, but at fuch a diftance, as, by the
turn of the head with fome curvature of the body, to reach
the fides and hinder parts, and from their conftru@ion and
pofition point out evidently, at leaft to me, that they were
weapons of defence againft fuch of its enemies as might at-
tack it in the flank or rear, and of deftruétive offence alfo in
fuch cafe. Of this more hereafter.

The neck is fo {hort that the animal could not reach the
ground with its mouth: the line from the withers to the end
of the under-jaw is about one-third of the line from the wi-
thers to the ground. I did-not take an aétual meafure of
this, but I will venture to affert it from my habit in drawing.

This animal, if a grazing animal, might indeed, as the
moofe deer do, feed on young fhoots of the woods, or the
bark ; or, by going into moraffes up to the breaft in water,
feed on the long graffes and water-plants which grow there-
in: but it is decidedly a carnivorous animal. The woods of
the earth in which this animal could live, move, and futtain
its being, muft have been totally diferent from fuch as at
prefent coyer the face of the earth; otherwife his enormous
form, with the pofition of his tufks, muft have rendered him
incapable of penetrating or pafling through them.

Now here. let the ingenuity and wit of our. philofophers
moft renowned as naturalifts fearch into the fa@, and tell
us what fort of animals could have been his prey, and where
fuch could exift in fufficient abundance to fuftain this enor-
mous animal ; and if any fuch ever did exift, which we now
know nothing of, how he could, . be his capacity for velocity
{uppofed to be what it may, how he could hunt them in woods
into which he could not penetrate, and through which he
could not pafs.

The queftion then arifes and remains in doubt, Where
muft we look for his habitation and his food? Not being
able to find either in the prefent ftate of the earth, my re-
fearch is led to feek it under fome other ftate of this planet.
In fearching for fuch {tate of things, I go to the firft informa-
tion we can obtain of the Ai/lory of this fact, in the divine
book of Genefis, written under infpiration: and there | am
tanght that the original ftate of this planet, in the fir/ period
of its exiflence, was that of an aqueous planet. ‘lhe waters,

over

ge

334 ‘On the Mammoth.

over the face of which the Spirit of God moved, covered the
whole furface of the globe, and had remained in that ftate
for two uncertain periods, until the working of nature under
the command of God forced up and elevated the earth in
parts, fo that the waters were gathered together, which took
60 in a third period of the progreffive exiftence of this our
anet.
i But apart all authority, any true philofopher, who meets
by tracing back the operations of nature in her progreffive
advance to the prefent ftate of the planet, will find it in its
firft period an aqueous planet; will find that light or caloric,
or whatever that firft power was, {pecially gave courfe to other
powers; and that the powers of evaporation, both expanfive
and attractive, were and are the caufes of the feparation of
the elaftic fluid, the atmofphere; that the earth has been
thrown up from the bottom of thefe waters by various ex-
plofions and volcanic eruptions: and that the earth became,
under thefe proceffes, in its vegetative ftate, a fit habitation,
firft, for the fowls of the air and all flying infeéts; and next
for the beafts of the field and all creeping things ; and laftly,
for man, exaétly according to the philofophic defcription
given in the divine narrative. But while he confiders this
advancing progreflion, he will find nothing to decide as to
the length and continuance of each of thefe periods. That

. thefe periods are not to be underftood as days, is part of the

fa&. Becaufe three of thefe periods were paft, according to
the narrative itfelf, before that divifion of time took place,
which was not till the fourth period.

I fhall now, grounding myfelf on the fact as above ftated,
affume that this planet was, in its firft period of exiftence, an
aqueous planet; and finding nothing to decide or determine
the continuance of this period, affume alfo that it continued,
according to the courfe of nature in her progreffion, in this
ftate for an indefinite period ; and further, that in this period
and in this ftate of the planet ‘* God created great whales
and every living creature which moveth, which the waters
brought forth abundantly after their kind.” I find it difficult
to conceive that thefe waters, which are defcriptively faid
thus to bring forth fo abundantly, fhould remain for four
periods of the planet’s exiftence totally unproductive till the
fifth. The only way that I find to reconcile this difficulty
in the divine narrative, is, that thefe marine beings are
omitted to be noticed until they are claffed with all other
living terreftrial creatures under one head, according to the
order of method, not the order of time, in the fifth period,
when the earth became a proper habitation for fuch vas

tria

On the Mammoth. 395

trial creatures. Whether the general denomination of great
whales, fo peculiarly expreffed here, extended to the levia-
than, the behemoth, and other fpecies of great animals, I
am not critic enough to judge: but that there were feveral
other great animals in thefe waters is a fact.

On this ground I am difpofed to think that, if any remains
of any great animals are found amid the wreck which the
parts of this planet have fuffered in the revolutions of its na-
ture, whofe {pecies are not now to be found in living exift-
ence, and to whom the prefent ftate of the earth could nei-
ther give an habitation or food, even a cautious naturalift
may, on theory founded in a combination of circumftances,
fairly fuppofe that thofe great animals had their exiftence
under the circumftanees of the firft period of this planet as
an aqueous one, and were deftroyed by the revolution which
converted it into a terreftrial one; and that even thofe who
were not deftroyed in that cataftrophe muft have become an-
nihilated, as the prefent ftate of the earth is not fuited to
their exiftence.

The fkeletons of this fpecies of animal, which is by a Ruf-

fian word denominated mamouth or mamoud, as being enor-
mous like the elephant, and which might juft as properly have
had the name leviathan, or behemoth, given to it, are found
in different and diftant parts of the world, and under different
climates, as on the banks of the Ohio, in the dominions of the
ftate of New Youk, and on the banks of the Obie in Siberia.
This cireumftance again points out that thefe animals muft
have inhabited fome element wherein the climates did not
vary to the degree in which they now do on the earth, and
whereby there was a.genera] free communication from one
fide of the globe to the other, which doth not now take
place. Moreover, as the earth is now conftituted, and as the
animals thereon exilt, the indigenous animals of Europe and
of America, howfoever fimilar in their external apparent
claffes, are variations in the one country from what they are
in the other.
_ Befides the fkeletons of thefe animals called mammoth,
there have been found in other regions of the earth parts of
other fkeletons of enormous animals, The fkeleton of one
fuch, which is now in Spain, was found in South America.
This, from the drawing made of it, appears to differ from
the mammoth: but, having been accuftomed to doubt the
vaguenefs of drauglits, I can {uppofe that this may, on-exa-
mination, be found to be of the fame nature ”.

There
* We have reafon to believe, from a correét drawing, and fome parti-
ewlars which have reached us of the animal here alluded tu, that it is ofa
ditterent

*

336 On the Mammoth.

There are alfo found, in different regions in the earth, the

exuviz and remains of animals of a fcale in magnitude
much beyond thofe it affords in its prefent ftate, about which
it feems almoft impoffible to fix any line of conjecture. They
are found in all ftrata, the marine ones chiefly in calcareous
ftrata: this fkelcton lay in a calcareous ftratum.
' The fuppofition that this animal was a marine one, and
dwelt in the ocean, relieves the account of it from all diffi-
culties as to its habitation and food. What the woods of the
prefent earth deny, the ocean gives full and free courfe to—
all its enormous animal capacities of motion. The a’ undant
Supply of the ocean could give food for this carnivorous ani-
mal, and food which came within its power to attain, on the
banks of flat fifth, and in the beds of fhell fith. This removes
all difficulty as to its fuftenance. That the ocean did bring
forth fuch food in fuch abundance, the phenomena of the
marine animal compofition of the firata of the prefent ftate
of the earth evinces.
That this animal was carnivorous appears to Be a decided
fa& ; it might therefore live in an element where was no
grazing foods from its enormous bulk it would require a fup-
ply of animal food which the earth could not give, and whicli
could only be found in the abundance which the waters bring
farth.

There are parts in the debris of the fkulf which have fome
comparative refemblance to the whale, as to the purpofe of
breathing under water; and from the width of the jaws,
Jomewhat fimilar to that of fifh, one may imagine, when
imagination is fet to work, that this animal might have had
in thofe parts fome glands calculated to carry on the famé
operation as the gills of fifh perform. The ribs, as obferved
above, more fimilar to thofe of fifh than to thofe of terref-
trial animals, are by their conftruétion and pofition ordained
to refift a much heavier and more forcible external compref-
fure than the atmofphere creates.

I fhall make no apology for any part of this ¢heory, be-
eaufe, being declared to be theory, every one is at liberty to
approve or difapprove the whole or any part thereof; yet I

_ gannot but think that fome very fober analytic philofophers
may repofe their imaginations if not their conviction upon
it, until the prefent or fome future fyftem of philofophy fup-

lies them with a better. I will therefore venture to fay to

any philofophical fociety, royal or liberal,

' ; Si quid novilti reétius iftis,

Candidus imperti: fi non, his vrere mecum.

different fpecies from the mammoth. We {hall here mention only one
fpecific difference—its ribs are nearly cylindrical. —Eprr. ;
I will

en

On the prefent State of Aéroflation. 337

T will not clofe my refle€tions on this fubje&t, which was
found in North America, and is now exhibited in London by
Mr. Peale, a young American, by whofe perfevering induftry it
was dug up, without faying in very truth, and not in compli-
ment, that this exhibition will derive every advantage which
can arife from an object of this fort, from the modett feien-
tific knowledge and the precifenefs of information which this
young man, in the true analytic way of an American, ex-
plains it; and from the colleétion of other articles with which
he accompanies fuch explanation as with a commentary.

LVI. Remarks on the prefent State of Aéroflation, By
Mr. G. J. WRIGHT*.

SupsrQuent to the difcovery of marine navigation, the
daily proofs of aérial flight, as witnefled among the feathered
tribe, ferved to fuggeft to the antients the probability of
piercing the unexplored regions of the atmofphere: various
have been their attempts for this purpofe, which (agreeably
to the then pre-emineuce of mechanical over the other
branches of philofophy) were confined to the invention of
machines to affift man himfelf in imitating the motions of
the feathered race, but more particularly to the contrivance
of flying automata, as may be learnt from the writings of
many authors.

To enumerate and particularize thefe inventions would be
of no avail, efpecially as the bare recital of many of them
would at once confirm their abfurdity ; fo that we may reckon
nothing to have been practically concerted toward aéroftation
till the experiment of one Gufman, a Portuguefe friar, who
is reported, early in the 18th century, to have launched a

aper bag into the air; which however foon fell, after attain-
ve, #4 height of 200 feet. ;
any doubts have arifen refpecting the truth of this ftate-
ment, principally from the fuppofed unacquaintance of the
hilofophers of that early period with the qualities and vary-
ing denfities of aérial fluids, as alfo the little probability that
an elaftic fluid could be confined, for any length of time, by
paper, of which it has been afferted that the pores are indeed
impermeable to air, though water eafily percolates them:
hence it has been inferred that the asitelei of water are finer
than thofe of air. ’Tis certainly true that air may be con-
fined by paper, provided fuch air be deftitute of moifture, and

* Communicated by the Author,

Vot. XIV. No 56. i incapable

Py “a *.@ een ae
Sl - rre neal Ba U ~o r " igs seeieee.

338 On the prefent State of Aérofiation.

incapable of exerting a chemical action thereon: but if water
pafles the pores of paper, it is moft probably occafiened by
its firft effecting a folution of the mucilage, by which means
the reft of the fluid finds an eafy paflage ; for, the hotter the
water, the quicker does it percolate; and this is not attributable
to any fuppofed attenuation of the individual particles of the
fluid, but to an aciual folution of the paper itfelf; otherwife
the ftrength of each fingle fibre would remain unimpaired
by the difference of temperature in the water; the contrary
to which the manufacture of paper itfelf will evince.

The difficulty, therefore, of obtaining the gafes in a flate
of drynefs in fo: large a quantity as is required for aéroftatic
experiments, will ever remain an impediment to the ufe of
paper for any other than balloons of {mall diameter, and on
the principle of Montgolfier. Two brothers of this name,
natives of France, confidering the difference in the fpecific
gravity of heated and cool air, juftly imagined, that if a bag,
ufficiently large, were filled with the former, the weight of
the inclofed heated air and bag together would be lefs than
an equal bulk of atmofpheric air of ordinary temperature, and
that {uch an apparatus would afcend till it fhould attain that
elevation where the refpective gravities would correfpond.

Experiment fully verified the opinion they had formed,
and M. Pilatre de Rozier was the firft to make trial of its
fecurity.

The inconveniences peculiar to machines rendered buoy-
ant by heated air, arofe from the impoffibility of keeping up
the elevated temperature of the inclofed air without the con-
pi renewal of fuel, and that in large quantity; whereby

e travellers were expofed to great danger from the occafion-

ally fudden and unavoidable expanfion of the flames, and their

inability to command that uniformity of rarefaction fo necef.
fary to the fafety of the voyage.

As aérial chemiftry had been before this time making rapid
advances, fo the philofophical world, through, the: indefati-
gable labours of the honourable Mr. Cavendifh, had been

- made. acquainted with the properties of inflammable air,
whofe fpecific gravity, in a tolerably pure ftate, is at leatt
twelve times. lighter than atmofpheric air. Doétor Black
firft applied this newly difcovered gas to balloons, by fuggeft-

~ ing its inclofurein anvair-tight bag, as capable of raifing it-
felf into the atmofphere, agreeably to the common hydrofta-
tical axiom, that bodies immerfed in a fluid heavier than.
themfelves muft inevitably float in that fluid; and that, as,
the denfity of fluids is proportionate to their heights, fo the
lighter body will continue to rife till its gravity. fhall corre-
fpond

On the profent State of Aéroflation.~ 339

fpond with that of an equal bulk of the fluid in which itis
immerfed. Although Dr. Black undoubtedly firft fuggefted
the propriety of applying inflammable air to aéroftatic pur-
poles, Mr. Cavallo had the honour of firft putting it into
practice, which we find him to have been engaged in per-
forming in the year 1782: but his experiments went no
further than a demonftration of the doétor’s fugeeftions ; and
the afeent of foap-balls filled with inflammable air (a3 being
the firft experiment of the kind) is an original idea, for
which we are indebted to him.
- The firft infammable-air-balloom was launched on the
continent by Meffrs. Roberts and a Mr. Charles in the year
14783; and the greater expediency of thefe latter machines
over thofe elevated by heated air, foon raifed them to that
pre-eminence they feemed juftly entitled to: yet even with
thefe there was conjoined the difadvantage of not being able
to raife or lower them without a lofs of ballaft in the firit, and
of gas in the latter cafe. | This fugeefted the idea of inclofing
‘a bag of heated air in one of inflammable air, whereby, on
varying the temperature of this inner balloon, the whole ap-
paratus could be raifed or lowered ad /ibitum, without lofs of
gas or ballaft. But as the vicizity of fire to hydrogen air and
common air endangers a mutual explofion, fo this unfortu-
nate plan deprived the world of that moft intrepid philofopher
M. Pilatre de Rozier, who has the honour to bear the palm
of aéroftation, in being the firft man who ever abandoned him-
felf to the atmofphere in a balloon...
_If we confider the natural difpofition of Frenchmen, ever
rompting them to the purfuit of novelty, we fhall not be
irprifed ‘to find them wari advocates for the progrefs of this
new art; eccentricity in the choice of their refearches and
ammufements having feek ever a- prominent trait in their na~
tional charaéter. Enlivened by the native foftnefs of their
climate, their difpofitions’ partake of that gaicty which is to
be found only in a country like theirs, where a lefs flugeifh
atmofphere and more uniform temperature tend to prelerve
a conftant vivacity of mind. <A latitude fo favoured with
ferenity of feafon produces an abundance of vegetables and
fruits, the want of a greater mixture of which in the diet of
Englifimen caufes the more prevalent fedatenefs of their
manners, fubdues a tendency to volatility, and keeps them
from wandering from one purfuit to another. Hence we
are lefs likely to watnefs amoug ourfelyes that fudden enthu-
fiafm for the progrefs of any new art, and efpecially of this
(to fome) feemingly unimportant one: we have therefore bad
very few inftances here of balloon excurfions undertaken by
Y2 really

340 On the prefent State of Aéroftation.

really philofophical men; and, except Mr. Baldwin, fione,
have contributed aught to the fcience. His treatife *, com-
piled from the memoranda of a fingle voyage, is without its
equal, and under fuch a philofopher the art muft foon have
attained all the perfection it could be capable of; while its
prefent low ftate can be attributed only to the impoffibility of
finding his rival. The treatife of Mr. Cavallo is an excel-
lent book for practical purpofes; and in thefe two volumes
we find all the yet afcertained facts relating to aéroftation { $
the pamphlets compiled by others being of no value, as con=
taining for the moft part a repetition merely of trifling occur-
’ rences of no avail to futare balloonifts.

Subfequent to the experiment of Meffrs. Charles and Ro-
berts, many voyages were undertaken, both in France and:
this country, during the years 1784 and 1485: and after the
public curiofity was in fome meafure abated, the purfuit itfelf
unk in the general opinion, and received attention only from
a Mr. Blanchard, a French gentleman, who for years before
had been devifing various methods to fly by mechanical
means. This amateur (who has made near fifty aérial voy-
ages, and who, in his feveral attempts to improve the art,
has met with fome unfortunate accidents) is tbe original in-
ventor of the parachute; but his effay therewith was not at-
tended with fuccefs to himfelf§, although the animals he at
times had committed to it for defcent never experienced the
flighteft fhock. Excepting then Mr. Blanchard, we find the
art making no further progrefs; and even the attempts of this
gentleman for the purpofe proved abortive. ‘

The fecond era of aéro{tation may be faid to commence
with the eftablifhment of the aéroftatic fchool at Mendon, in
the vicinity of Paris ||; and the firft immediate fervice of a
balloon appears to have been derived in the battle of Fleurus,
in the Auftrian Netherlands, where, from an elevated ftation
the French aéronaut beheld the movements of the enemy $
and by indicating the fame by a telegraph purpofely attached
to the car, the battle is reported to have been gained by the
French, principally from this contrivance to overlook the ope-

* Aéropaidia, or Narrative of a Balloon Excurfion from Chefter; by
T. Baldwin, A.M. 1786.

+ Hiftory and Pragtice of Aéroftation; by Tiberius Cavallo, F.R.S.
London 178s.

t Inthe French language we have Deéfeription des Expériences Aérofla-
tiques, par M, Fayas St, Fond, 2 tom.

§ In an experiment at Bale, in venturing to defcend by his-parachute,
he unfortunately broke his leg. :

\| See the account of the French aéroftatic inftiwute in te fixth volume
of the Monthly Magazine. ;
rations

On the prefent State of Aéroftation. 341

rations of the combined armies. Various reports have at
times reached us concerning the pretended flourifhing {tate
of this aéroftatic fchool; but during the few years of its efta-
blifhment no improvements appear to have been made further
than the compofition of the varnifh, which is brought to the

eateft perfection ; and Mr. Garnerin informed me the efta-
Biihisent itfelf is now given up.

We find then that the apparatus itfelf has undergone no
confirmed improvement; perhaps from the purfuit being ge-
nerally attended to by enthufiafis in novelty, ftrangers to ge-
nuine fcience natural or mechanical. Thus an agronaut in
the prefent day is compelled to go in the direction of the
wind ; and in defcending, calmly fits in his car to be knocked
again{t every tree, houfe, or hedge, that may come in his
way. So long, therefore, as aérial adventurers are liable to
fuch dangerous dilemmas, it is no wonder we find fo few in-
clined to repeat their voyages; as the tranfitory enjoyment of
a view above the clouds, is feldom fufficient to incite a fecond
attempt under fuch threatening circumftances.

The reftoration of peace affording to foreigners an oppor-
tunity of vifiting this country, whether prompted by curiofity.
or to exhibit the productions of their inventive genius, this
erifis proved a means of again exciting the attention of the
Englith public to the almoft forgotten fubjeét of aéroftation,
as revived by the advertifements of Mr. Garnerin; a man of
an ingenious turn of mind, without that collateral acquaint-
ance with the feveral fciences on which refts the only fure
foundation for improving the arts, and efpecia!!y this pecu-
har branch of philofophy, which feems to be his native forte.

Having made a number of aérial voyages, his mechanical
acquaintance with the requifites for infuring fuccels was con-
firmed by frequent experience; but further than this we do
not find him to have attained. He is alfo the firft acronaut
that has fucceeded in a fafe defeent by'the parachute—an ex-
periment which is of the firlt confequence to the progrefs of
aéroftation. The late voyages made in this country by this
latter gentleman are frefh in the memory of every one, and
we have only to regret that fo experienced an adventurer
fhould poffefs fo fmall a fhare of the knowledge requifite to
raife aerial navigation to the perfeétion it might perhaps
otherwife foon attain. .

As an advocate for afcertaining the fue of whatever may
be dubious in the prefent ftate of our knowledge, | felt anx-
ious to feize fo happy an opportunity of inveltigating what
degree of diminifhed preflure the human conftitution could
fupport, as prefented in the intended experiment with the pa-

X¥3 rachute ;

342 On.the prefent State of Aéroflation,

rachute: for this reafon I offered to Mr. Garnerim, that, as-
his balloon was capable of carrying four perfons, it would be
fully adequate to the conveyance of two, together with the,
parachute and ballaft: under fuch circumftances it would be
neceflary to fufpend the parachute beneath the car; and my
intention was to occupy the latter myfelf. An offer fo ad-
vantageous for fecuring Mr. Garnerin’s machine (otherwife
left at randoms) was rejected by him, from the acknowledge-
ment of his doubts re{pecting the event of fo novel an expe-
riment. But I truft this experiment will not long remain
unattended to by fuch as may have an opportunity of per-
forming it: the effects fubfequently taking place from the
Jofs of a weight of upwards of 200 pounds at an elevation of
10,coo feet, are not fo terrific as might be imagined; as
‘during this after-afcent no danger could attach to the ma-
chine; for, its neck being open, and thereby affording an exit
to the gas, now fomewhatmore expanded by the abfence of
the mechanical preffure of the 2-0 pounds juft loft, yet gra-
dually {till more expanding itfelf as it attains in this alcenfion
a zone of air of Jeffer denfity, would neceflarily prevent any
rupture from that caufe ; while, if the a¢ronaut found his re-
fpiration too much affected to allow his attainment of the ut-
moft height futmountable under thefe circumftances, he could
have nothing to fear fo long as he has the yalve at command.
Neither have we any caufe for apprehenfion from the velocity,
likely to take place, if the traveller is not too near to the body
of the balloon, or in a fitting pofition; in both which cafes
it 3s doubtful whether the approximation. to a vacuum * in
the wake and immediately in the vicinity of the lower pole
of a large fpherical body, afcending with great velocity, might
not endanger a/phywia, from the fuddenly diminifhed denfity
of the air received into the lungs +.

At the fame time, to fuch as defcend by a parachute from
a balloon left at random, I would advife an attention to the
following fimple precaution, which cannot fail of infuring the

* Agreeably to what we learn in projeétiles, that a body moving with a
velocity of 1200 feet in a fecond, leaves behind it an aétual vacuum; alfo
exemplified in the common exercife of fwinging, where a flightly fuffo-
cating fenfation is experienced in the retrograde morion of the machine,
oecafioned by the perfon fitting in the wake formed by the recoil of his
own body. ; ,

+ As I have no intention to fpeak.in this place of the effeéts likely to
enfue to an aéronaut in cafes where, the valve being unexpeéted|ly found out
of repair, he is obliged to remain at the then unavoidable equilibrium, I
fhall referve thefe points of difeutlion as the fubjeét of a paper I propofe to
tran{mit at a future opportunity, in immediate reference to the probable
effecls of diminithed atmofpheric preflure on the animal fyftem.

{peedy

os

On the prefent State of Aéroftation, 343

fpeedy defcent and recovery of the latter. In afcending with
a parachute according to the prefent conftruction (the aéro-
naut being out of the reach of the neck of the balloon), it will
be advifable to leave the neck open aboutia foot or more’
previous to the afcent procure a cord whofe length muft equal
half the perpendicular circumference of the balloon when at
its full-diftenfion 3 attach one end of the cord to the zenith
of the balloon externally, or to the netting immediately over
it, and (leaving it detached throughout the whole of its re-
maining length) to the other end faften a weight of about
20 pounds. I fay, when the feparation between the para-
ehute and balloon is made, the latter, being deftitute of any
other poife, will gradually yield to this above-mentioned
weight, and by its means the open neck of the balloon will
progreffively be made to afcend; while the zenith will be
drawn downwards, the machine thereby inverted, and the
preffure of the external atmofpheric air will in a fhort time
force out the inflammable gas, and the whole bag quickly
defcend *.

It would appear, from the above fhort review of the ftate
of aéroftation, that we have as yet made no further progrefs
than the attainment of the means of rifing into the atmo-
{fphere, of afcending and defeending a very limited number
of times, and of departing from the machine in fafety in cafe
of any immediate with on the part of the traveller when his
ftay therewith appears hazardous, As thefe are matters fufs
ficient to difpel apprehenfion from the minds of thofe who
may be inclined to attend to this branch of philofophy, it
may not be amifs to fubjoin thofe requifites and precautions,
an attention to which will not fail to enable the amateur to

urfue this modern difcovery with expedience and economy.

The ftuff uniformly made ufe of in the conftruétion of bal-
loons to be raifed by inflammable air is filk luftring, (taffetas
lufiré,) which is a fabftance extremely well calculated for the
purpofe, as poffefling the valuable properties of clofenefs of
texture and uncommon ftrength, yet of little weight +: a

% the

* Finding Mr. Garnerin, notwithftanding repeated applications, averfe
tomy accompanying him in the manner I propoled, 1 advifed him to take
advantaye of this exfy method of securing his machine ; but he chofe
rather to follow his own uncertain projet at fiftening the neak of the bal-

, inorder that, as it afterwards continued to afcend to a more rere at-
molphere, the force of the éxpaniding inflammable air (thus prevented from
efcaping) might ov.rcome the refittence of the fill, and caufe a rupture
fafficient to’ let our the vas: but iv our {niall iMand the machine might
pe been irrecoteralily loft in the ocean before thefe eiteéts had taken

ace. é
+ Balloons to be raifed by heated air are conttrudted of linen foaked

Y 4 bp

344 On the prefent State of Aéroftation.

the price of this filk, though more moderate in France, is im
this country fo high * us to augment the expenfe of a middling-
fized balloon almoft to a prohibition to any but the wealthieft
individuals. I.do not fee, therefore, why ftrong ecambric
muflin, rinfed in drying oil+, (previous to fewing the pieces
together,) fhould not fully anfwer every purpofe. After pro-
viding the neceflary quantity of the ftuff, and each piece hav-
ing been properly prepared with the drying oil, let the cor-
re{ponding edges be fewed together in fuch a manner as to
leave about half an inch of one piece beyond the edge of the
other, in order that this may, in a fubfequent row of {litches,
be turned over the latter, and both agai fewed down toge-
ther: by fo doing, a confiderable degree of ftrength is given
to the whole bag at the feams, and the hazard of the gas
efcaping doubly prevented. Having gone in this manner
through all the feams, the following method of Mr. Blan-
chard is admirably calculated to render them yet more per-
feGtly air-tight. The feam being doubly ftitched as above,
lay beneath it a piece of brown paper, and alfo another piece
over it on the outfide; upon this latter pafs feveral times a
common fire-iron heated juft fufficiently to foften the drying
oil in the feam : this done, every interftice will be now clofed,
and the feam rendered completely air-tight.

The neck of the balloon being left a foot in diameter and
three in length, and all the feams finifhed, the bag will be

ready to receive the varnifh, a fingle coating-of which on the -

in a folution of alum or fal-ammoniac and common fize: Mr. Ca-
vallo recommends a gallon of water to a pound of each of the two ingre-
dients: it may then be fewed into the required fhape, and afterwards once
varnifhed on the outfide with merely drying linfeed oil, adding a fmall
quantity of neat’s-foot oil to prevent its being fticky. The /iquor filicum,
or liquor of flints of the chemifts, prepared by melting together one part
_ of fand or powdered flints and four parts of fixed alkali, might, perhaps,
be advantageoufly fubftituted for the faline ingredients above mentioned,
as rendering paper or cloth varnifhed therewith perfectly incombuftible.

* Silk luftring may be purchafed on the continent at five fhillings the
yard, but here for not lefs than nine. ,

+ In rendering oil drying for aéroftatic purpofes we fhould avoid the
ufe of metallic oxides, as litharge, &c., which rot the ftuff of the enve-
lope; befides that hydrogen gas, by gradually reducing the metals, cor-

_ rodes fuch varnith, turning it black, and in time caufing it to crack. The
beft method to prevent thefe inconveniences is to allow the oil to ftand for
feveral weeks over unflaked lime, or to diffolve in it a fmall quantity of
gum-fandarac, gum-lac, maftich, feed-lac, or common refin; all of which,
when finely powdered, may be diffolved in linfeed oil by well boiling,
thus communicating to the oil the property of drying, yet retaining clafti-
citys Silk and canvas for umbrellas, &c, are varnifhed with a folution of
either refin or gum-lac, melted with drying linfeed oil to the confiftence of
a thick balfam, fo as not to run about: thus varnifhed they are very little-
heaviex than before, though impermeable to air or water.

outfide

On the prefent State of Aéroflation. 345

outfide is found preferable to the former method of giving an
internal as well as an external coat. The compofitions for
varnifhing balloons * have been varioufly modified; but,
upon the whole, the moft approved appears to be the bird-
lime varnifh of M. Faujas St. Fond, prepared after Mr. Ca-
vallo’s method as follows :
“* Inorder torender linfeed oil drying, boil it, with two ounces
of fugar of lead and three ounces of litharge + for every pint
of oil, till they are diflolved, which may be in half an hour.
Then put a pound of bird-lime and half a pint of the drying
oil into an iron or copper veflel whofe capacity fhould equal
about a gallon, and let it boil very gently over a flow char-
coal fire till the bird-lime ceafes to crackle, which will be in
about half or three quarters of an hour: then pour upon it
two pints and a half more of the drying oil, and let it boil
about an hour longer, ftirring it frequently with an iron or
wooden fpatula. As the varnifh whilft boiling, and efpe-
cially when nearly done, fwells very much, care fhould be
taken to remove in thofe cafes the pot from the firé, and re-
place it when the varnith fubfides; otherwife it will boil
over. Whilft the ftuff is boiling the operator fhould occa-
fionally examine whether it has boiled enough; which may.
be known by obferving whether, when rubbed between two
knives and then feparated from one another, the varnith
forms threads between them, as it muft then be removed
from the fire: when nearly cool, add about an equal quantity
of fpirit of turpentiné: in ufing the varnifh, the ftuff mutt be
ftretched and the varnifa lukewarm: in 24 hours it will be
dry.” ae )
Biers balloon fhould be provided with a valve fo con-
ftru&ed as to open inwards, having alfo-a {pring to keep it
fhut. The {tring by which this valve is regulated muft pafs
through a {mall hole in the lower part.of the balloon to the
car; its length mutt be fuch as to allow feveral. coils of it to
remain in the boat: this is a requifite precaution, as, when
the inflammable air is much expanded, the horizontal dia-
meter of the balloon is fo much more extended, and its lower

* As the elaftic gum, known by the name of Indian rubber, has been
much extolled as a varnifh, the following method of making it, as prac-
tifed by Mr. Blanchard, may not prove unacceptable :—Diffolve claftic
gum, cut fmall, in five times its weight of reétified effential oil af turpen-
Ber inereal {pirit of turpentine of the fhops,). by keeping them fome days
together; then boil one ounce of this folution in cight ounces of drying
linfeed oil for a few minutes ; firain the folution, and ufe it warm,

+ The metallic oxides are lefs exceptionable in the outer varnith of a
balloon than internally, as the firft foaking in drying oil ferves to thield
the external varnish from the action of the gas,

pole

345 Memoir on the Properties. of ¥iiria Earth

pole confequently drawn proporiionably upwards, that the
firing of the valve will be otherwife out of the traveller’s
reach; an accident which has frequently obliged them to
climb up into the netting to regain it, The valve itfelf
fhould be covered with foft leather, reaching an inch or two
beyond its edge every way. Its fituation fhould be upon
the equator *, (and not, as generally directed, near the top,)
elfe the lighteft gas will be that which will efeape; not to
mention alfo the greater inconvenience in the latter cafe,
arifing from the eftablifhment of a complete current of atmo-
fpheric air through the balloon by the neck and valve toge-
ther (the neck being generally left open a few inches), where-
by a quantity of the lighter gas is carried off greater than one
would imagine. To obviate this, the neck and valye fhould
never be both open at one time; and I apprehend the acci-
dents frequently oceafioned by the ufually rapid defeent and
rebounding of a balloon, are to be attributed to an inattention
to this precaution; the gas being violently carried out of the
valve by a current of air running through the balloon, and
this current inereafing with the velocity of the defcent; fo
that, when the valve is again clofed, the balloon is found to
have decreafed in levity much more than was wifhed for.

The car for balloons may be left to the option of the ama-
teur, remembering that light weight, and the property of
floating if defcending over water, be attended to.

: iy [To be continued. ]

LVI. Extra from a Memoir on the Properties of Yitria
Earth compared with thofe of Glucine; on the Foffils in
which the former of thefe Earths is contained; and on the
Difcovery of anew Subfiance of a Metallic Nature. By
A. G. EKEBERGH. . .

‘Tue firft part of this memoir contains an account of
fome experiments, made by M. Ekeberg, to eftablifh the
difference between glucine and the earth difcovered in the
gadolinite, and called yttria or gadoline; but as the pe-
culiar nature of each of thefe earths is already well known

* The opening of the valve being fometimes required during the rapid
afcenfion of a balloon, and being foliowed alfo by a quick defcént, the

equator is pointed’ out as the moft proper fituation in which to place the ~

talve, to prevent the atmofpheric air fomrufhing in either cafe into the
bulloon. ;
+ From the Tranfactions of the’ Academy of Sviences at Stockholm for
1fo2, firft quarter, : _
to

a
:

compared with thofe-of Glucine. 349- °

to chemifts, it is here needlefs to repeat what-has been
already faid on that fubjec.

As the other is interefting on account of its novelty, we
fhall lay before our readers the obfervations made on it by
the author, /

Though the mineral fubftance I difcovered, fays he, con-
tains yttria, it could not be clafled in a fyfem of minera-
logy as a {pecies of earth, on account of the more abundant
mixture it contains of another fubftance equally remark-
able, and which muft increafe the clafs of metals, already
yery numerous. [ found this fubftance in two foffils, ob-
tained from different places: in one of them, it was united
with iron and manganefe ; and in the other, with the former
of thefe metals and gadoline,

This new metallic fubftance is diftinguifhed by its info-
lubility im all acids. The only re-agent which has any
action on it is cauftic fixed alkali, When fubjected to heat
with this alkali, if the mafs be then lixiviated, it partly dif-
folves in the water, and fuffers itfelf to be precipitated from
that folution, by means of an acid—but without the preci-
pitate heing in any manner attacked, whatever be the quan- -
tity of the acid employed. When feparated by the filter,
and dried, it remains under the form of an exceedingly fine
white powder, which does not change its colour even at
a red heat. If the remaining ma{s’ be treated with acids,
the fame powder is obtained, Its {pecific gravity, after be-
ing brought to red heat, is 6500. It is futible by the blaw-
pipe, by the addition of alkaline phofphate and borate of
foda, but communicates no colour to the flux.

Expofed to a ftrong heat in a crucible, without any other
mixture than pounded charcoal, it»is reduced to a button
moderately hard, having fome metallic fplendour at its fur-
face, but a dull blackith fracture, Acids have no other
aétion on this kind of regulus, but that of bringing it to the
itate of white oxide in which it was before. The circum-
ftances of the reduction, as well ag the fpecific gravity of
this fingular fubftance, feem to aflign it a place among the
metals, and [ have fufficient reafons for being penne
that it is none of thofe already known, ‘The fubfiances
with which it might be confounded are the oxides of tin,

ungfien, and titanium, which are foluble in cauftic alkalies,
and which, under fome circum{tances,, refift acids, But
the oxide of tin is eafily diffolved and reduced: tungften
immediately difcovers itfelf by its folubiliry in ammonia,
and by the blue colour which it communicates to phol-

phate

+
;

348 Memoir on the Properties of Yttria Earth

phate of foda: the oxide of titanium gives a hyacinth co-
lour to borax, and becomes foluble in acids by fufion with
carbonate of potafh*.

Before I deferibe the chemical analyfis which I under-
took of the two fubftances, which I confider as ores of the
new metal, it is proper I fhould give a defcription of their
external characters. In order to avoid circumlocution, when
neceflary to name them [ fhall venture to give them a ge-
neric denomination. Taking advantage of the ufage which
admits mythologic appellations, and to exprefs the property
which the new metal has, of not becoming faturated with
the acids in which it is immerfed, I fhall apply to it the
name of Tantalus. For the ore compofed of tantalus, iron
and manganefe I propofe the name of tantalite; and for the
ore containing yttria, that of _y¢/rotantalite, which will not be
found longer than that of /iderotitanite.

The fpecimen of tantalite was given to me by M. Geeger,
direétor of the mines; who affured me that this fubftance
has been known fince 1746, and confidered as a problematic
variety of the garnet of tin, (zimmgraupen.) It is found
near the farm of Brokaern, in the parifh of Kimito, and go-
vernment of Abo, in Finland, in a large mountain on the
borders of the Baltic. The matrix is compofed of white
quartz and mica, with veins of red feldfpar in large Jamine,
matters of which the fides of the vein are formed: the tita-
nite is found difperfed throughout it, in the form of garnet.

What I faw was in detached cryftals, of the fize of a
walnut, and the beft defined feemed to approach the oc-
thaedral form ; they were charged with parcels of feld{par and
mica.

Its furface is fmooth, fhining, and blackifh.

Its fracture is compaét, and has a certain metallic fplen-
dour: the colour of the fracture is not every where the fame ;
it varies between grayifh blue and the black of iron.

When powdered, it is blackifh gray inclining a little to
brown.

It has fufficient hardnefs to ftrike fire with fteel.

I have not obferved that it has any attraétion for the
magnet.

- Its fpecific gravity 1s 7°953-
- The yttrotantalus is found in the fame place and in the
fame matrix asthe gadolinitc. Klaproth fays that the latter

* J had, however, entertained fome fufpicions in regard to the identity
of the new (ubftance and the laft-mentioned metal; and | was not fully
convinced of its not exifting, but by comparing it with the titanized iron
of Norway, which J decompofed for that purpofe,

*

43

=

compared with thofe of Glucine. 349

is found incrufted in a granitic mafs¢ but though the confti-
tuent parts of granite are found there from time to time, it is
no lefs certain that the real matrix is nothing elfe than feld-
{par, as is evidently feen in the large mine of Ytterley. The
mica and quartz found there form diftin@ parts, and do not
enter, into combination with the feldfpar* ; but in general it
is a rock of feldfpar, interfeéted by large veins of mica, in a di-
rection almoft perpendicular; and itis in the proximity of thefe
veins that the gadolinite as well as the yttrotantalus mutt
be fought for. -The firft is generally found attached on one
fide to a vein of argenteous mica, and the reft of its volume
enveloped by feldfpar. The fecond never adheres immedi-
ately to the mica. The clumps (rognons) which it forms,
become enveloped with a thin crutt of feld{par, feparate from
the grand mats by thin ftrata of grayifh black mica. The
veins charged with thefe rognons are rarely infulated ; feveral
of them are found together, feparated only from each other,
and from the principal rock, by fimilar fides of mica. It
was thus that I for the moft part found thefe fubftances
placed by nature, and it is very rarely that they are found in
grains diffeminated throughout the rock of feld{par. .

The largeft rognons which I found of the ore of the yttro-
tantalus had not attained to the fize of a walnut. The
fracture of them was granulated, of an iron black colour, with
a metallic fplendour. |

Its hardnefs is not confiderable ; it can be fcraped by means
ef a knife, but with difficulty.

When powdered it is of a grayith colour.

It exercifes no aétion on the magnet.

I found its fpecific gravity to be 5130; but as it was not
podible for me to find a piece entirely free from feldfpar, I
* ected that its real oravity muft be a little more confider-
able,

We fhall terminate this extra& by a fhort view of that.
part of M. Ekeberg’s memoir, which relates to the analyfis
of the gadolinite, and the comparifon of the yttria with
glucine, which in feveral works has been confidered as being
of the fame nature.

Gadolinite, when pure, is fufficiently compa& to ftrike
fire with fteel.
_It is found cryftallized in an imperfect manner, like fomé
kinds of garnets.
It contains glucine.
* Lfpeak here only of the maffes of the principal reck, without deny -

ing the potfibility of finding there fome fragments in which the three fub-
flanccs are intermixed.
Befides

459 On the Change which Carbonic Acid Gas

_ Befides the diflin@tions eftablifhed by Klaproth and Vau-
- guelin between the gadoline and glucine, thefe two earths
appear to be different by the following peculiar properties :

The {pecific gravity of gadoline differs confiderably from that
of glucine, which is only 2°967, while that of gadoline is 4-342.
The lafi earth is the heavieft of all the earthy fubftances

known; fince it furpafles by 0-482 the gravity of barytesy.

which weighs only 4:000.
It is foluble in alkaline carbonates.
It is abfolutely infoluble in cauftic alkalies. .
It is not, like glucine, precipitated by fuccinates.: |

Se ee ee eee

LVIII:. Obfervations on the Change which Carbonic Acid Gas
experiences by the Eleétric Spark, and on the Decompofition
of the fame Gas by Hydrogen Gas. By THEODORE DE
Saussure*. (ROE

I. Change which Car!onic Acid Gas experiences by the Elec
tric Spark.

Dr. PRIESTLEY had obferved that carbonic acid gas
dilated by the electric {park, and experienced a modification
which prevented it from being entirely abforbed by lime water,
or by alkalies. C. Monge examined with the greateft care
what took place in this experiment, and found that the gas
produced by eleétrifation was inflammable gas. I thall here
defcribe in a few words the principal refults of this obferva-
tion: A column of carbonic acid gas, of 34 inches, contained
by mercury, rofe to 35 inches and a half, after having been
traverfed for a long time by electric {parks, which circulated
between iron conduGtors. It could not be dilated any more
by further eleétrifation. The wires as well as the mercury
were oxidated. Potafh could only abforb 21 inches and
a half of this column of acid gas: the remaining.14 inches
were inflammable gas., C, Monge accounts for thele phe-
nomena by fuppofing that the carbonic acid gas does not
experience the leaft alteration in its principles, and he rea-
fons nearly as follows: The conductors and the mercury, by
decompofing the water held in folution in the carbonic acid

as, produce two oppofite effects, of which nothing 1s ob-
fra but the difference. | 1{t. The volume of the acid gas
is dimninifhed, by being deprived of the water which it held
in folution. 2d. The volume of the elaftic fluid is augmented,
by the developnient of the hydrogen gas of the water de-

* From the Journal des Mines, No. 68.

'

compofed ¢

experiences by ihe. Bleéric Spark. 35%

sompofed. The refiduums of, gas after the operation are @
mixture of hydrogen gas, refulting from the decompofition
of the water, and carbonic acid gas deprived of water.

This very ingenious explanation® was without doubt the
only one which could prefent itfelf at the time when it was
given. Had it been juft, it would have been neceflary, by
reftoring to the acid gas'condenfed by defiecation, the water
it had Jott, to dilate it again, and to augment about 12 inches
the column in gueftion., As C.-Monge did not fubmit his
explanation to this decifive proof, 1 thought proper to at-
tempt it.

I caufed to cireulate for 18 hours electric fparks in the
bulb of a matrafs which contained 13 cubic inches of pure
carbonic acid gas, and without any mixture of water fuper-
abundant to that which it might naturally bold in folution.
The mereury, in which, the inverted matrafs was immerfed,
rofe to about the half of its neck. After eleGtrifation, the
metallic fluid was found oxidated black, as had been obferved
by Monge and Prieftley; but my conduétors, which were
of copper, were not fenfibly altered. The elaftic fluid had
experienced a {mall dilatation, which appeared to me not to
exceed the tenth part of ‘a cubic inch. [ then made about
a grain of waterf to pafs in contact with the aériform gas
contained in the matrafs. .1 let it remain there for feveral
days, without perceiving amy dilatation in the volume of the
gafes, the refidua of the operation. 1 then moiftened, with a
drop of water which I introduced, the whole infide of the
matrafs—but in vain—the mercury conftantly remained at
the fame height. [ however found, om abforbing by potath
the refiduum of the acid) gas, that acubic inch of carbonte
acid gas. had difappeared, and had been replaced by a quan-
tity nearly equal, or rather faperior, to the inflammable gas.
The 20 cubic centimetres. oecupied:in the neck of the ma-
trafs a column four inches in length; and the acid gas, had
the fuppofed explanation been jult, would have been dilated

* Tt fuppofes that the carbonic acid gas may hold in folution a great
quantity of water, Bat this, affériion is not proved by any other direét
experiment, Dr. Prieftley was notable to calcine carbonate of harytes
bur by the help of a cusrent of aqueous vapour, which he caufed to cir-
culate on that earth brought toared heat. This refult may. be explained
be Dog affinity alone of the warer for the barytes. [It is befides poflible

the carbonic acid gas diifotves at a red héat a certain quast'ty
water, and dilates much ih this folution, without producing thee effedts
at the temperature of the aunofphere. :

+ Iris needlefs to obferve here, that water cam abforb no more than ite
own volume of acid gas with the preflure of the armofphere, and thas
the drop of water introduced into the matrafé could not produce by, this
abforprion any ferfitle change in the volume of the claftic fluid.

through

352 On the Change which Carbonic Acid Gas

through all that {pace. I then thought that this inflammable
gas did not arife from the decompofition of the water, but
from that of the carbonic acid itfelf by the metal. I indeed
found that this gas was not hydrogen gas, but carbonous gas
perfeétly pure. I burnt roo parts of it on mercury, with
about a third of oxygen gas. I did not perceive water after
this combuftion, which left for refiduum 77 parts of car-
bonic acid gas.

The dilatation which the latter experiences by electrifa-
tion may be explained by the different denfities of the car-
bonous gas and the carbonic acid gas. I was not able. to
verify the obfervation of C. Monge refpeting the dilatation
experienced by the carbonic acid gas, after electrifation over
mercury.

If it was not poffible to reduce entirely the acid gas into
carbonous gas by thefe proceffes, it was becaufe the firft
ftrata of metallic oxidation prefented an obftacle to further
oxidation, by preventing the points of contaét. The deve-
lopment of the carbonous gas produced therefore an analo-
gous effect.

It refults then from my obfervations, that the change
which carbonic acid gas undergoes by eleétrifation does not

arife from the decompofition of the water, but from the par-

tial decompofition of the carbonic acid gas, which becomes
carbonous gas, giving up a part of its oxygen to the metal
introduced in thefe experiments.

II. Decompofttion of Carbonic Acid Gas by Hydrogen Gas.

Tt was long fuppofed that carbonic acid gas could be
decompofed by hydrogen gas; but no one was able to
effect it, though many experiments were made on that fub-
ject. Thad obferved, that a mixture of equal parts of hy-
drogen gas and carbonic acid gas, contained by mercury
and left to itfelf, had decreafed in volume in the courfe of a
year. When I then caufed the refiduum of acid gas to be
abforbed by potafh, and had burnt the hydrogen gas, I found
that there was formed in this combuttion carbonic acid gas:
but thefe refults were not very fenfible ; and what took place
in this operation was to me mere conjecture. Since that
time I have been able to confirm in a decifive manner this
firft obfervation, by caufing the ele@ric fparks to circulate in
a mixture of carbonic acid gas and hydrogen gas. Ina few
moments I faw the volume of the gas decreafe, drops of
water formed, and the acid gas pafs almoft entirely to the
ftate of carbonous gas. The following are the details of one
ef thefe experiments: I introduced into a cylindric glafs jar

ae, about

Some Account of Richard Kirwan, E/q. 353

about nine lines in diameter, and clofed by mercury, a mix-
ture of four parts in yolume of carbonic acid gas, and three
parts of hydrogen gas. The {pace occupied by the two aéri-
orm fluids united formed a long column of feven inches, fo
that each part in volume of the glafs correfponded to one
inch in length of the column. I-caufed the electric {park to
circulate by iron conduétors. The condenfation of the gas,
which at firft took place very rapidly, became always flowers
after twelve hours electrifation, its progrefs was almoft infen-
fible. The very fine drops of water, formed during the ope-
ration in the upper part of the tube, difturbed its tranfpa-
rency. The column of aériform fluid was reduced to four
inches. ,[t then experienced in its length a diminution
equal to three inches. I then introduced into it potath, which
could abforb only one inch of carbonic acid gas. The three
remaining inches were carbonous gas almoft pure. I burned
by means of the electric fpark, 100 parts of it with oxygen
gas, and they left for refiduum 64 parts of carbonic acid gas.
‘It is feen, then, that three inches of carbonic acid gas were _
decompofed, and paffed to the fate of carbonous gas, by
combining a part of their oxygen with the hydrogen gas in-
troduced.. It is feen alfo that the latter, by lofing the
elaftic ftate to form part of the water refulting from this com-
bination, produced the condenfation obferyed in the yolume
‘of the two gafes.

Tt is to. be remarked, that the mercury and conduétors in
this experiment were not confiderably oxidated.

~ It has long been obferved, that hydrogen gas, confined by
water in contaét with atmofpheric air, decreafes very flowly
in volume, and then burns with a flame lefs vivid. It has
been fuppofed that this gas filters through the water in the
‘atmofphere ; but there is nothing to fupport this explanation.
‘In my opinion, it is more probable that the carbonic acid
gas of the atmofphere filters alone through the water, ac+
cording as it is decompofed by the hydrogen gas, which de-
ereafes in the ratio of this decompofition.

LIX. Some Account of RICHARD Kirwan, Ejg. LL. D.
F.R.S. and P.R.ILA. |

Tus gentleman, who has diftinguifhed himfelf fo much
by his philofophical and geological labours, was bred to the
law, and exercifed his feftion as a barrifter, till infirm
health, and the death of his elder brother, a member of the
Trith parliament, occafioned him to become an experimental

Vor. XIV. No. 56. Z inquiret

354 Some Account of Richard Kirwan, Ejy.

inquirer into the phenomena of nature. Having devoted his
attention to chemiftry and natural philofophy, he fet out in
this new mode of life, in or near London, about the year
1979 or 1780. He made his debut with fome papers read
in the Roya! Society, for which he received the Copley
medal, about the year 1781. The titles of thefe papers are
as follow :—Experiments and Obfervations on the Specific
Gravities and Attractive Powers of various Saline Sub-
ftances: read Nov. 16, 1780.—Continuation of thefe Experi-
ments and Obfervations: read April rr, 1782.—Conclufion

of the Experiments and Obfervations concerning the Attrac- .

tive Powers of the Mineral Acids: read Dec. 12, 1782.—
Remarks on Mr. Cavendifh’s Experiments on Air: read
Feb.5,1784.—Remarks on Specific Gravities, taken at differ-
ent Degrees of Heat; and an eafy Method of reducing them
to a common Standard: read Feb. 17, 1785.—Experiments
on Hepatic Air: read Dec. 22, 1785.

’ Mr. Kirwan returned to his native country about the year
1789, and fome time after was appointed Prefident of the
Royal [rifh Academy; a place which he continues to hold,
with honour to himfelf and advantage to the philofophical
world. The papers with which he'‘has enriched the Tranf-
‘actions of the learned body over which he prefides are: An
Effay on the Variations of the Barometer: read March 1,
1788.—Obfervations on Coal Mines: read Jan. 10, 1789.—
Experiments on the Alkaline Subftances ufed in Bleaching ;
and on the Colouring Matter of Linen Yarn: read April 4,
-1789.—On the Streneth of Acids and the Proportion of In-
eredients in Neutral Salts: read Dec. 24, 1790.—A Com-

parative View of Meteorological Obfervations made in Ire- |

land fince the Year 1788, with fome Hints towards forming
Prognottics of the Weather: read Feb. 2, 1793.—Reflections
on Meteorological Tables, afcertaming the precife Significa-
‘tion of the Terms Wet, Dry, and Variable: read July 23,
“1793.—State of the Weather in Dublin from the rft of
June 1791 to the1ft of June 1793.—Examination of the
fuppofed Ieneous Origin of Stony, Subftances: read Feb. 3,
1793.—ffav in Anfwer to the following Queftion, propofed
-by.the Roval Irify Academy’: What are the Manures -moft
advantageoufly applicable to the various Sorts of Soils, and
what are the Caufes of their beneficial Effe&t in each parti-
eular Inftance? réad Jan. 4, 1794.—Meteorological Obfer-
‘vations ade in Ireland in the Year 1793: read Jan. 25, 1794.
—Experiments ‘on a’ New Earth found near Stronthian in
Scotland: réad Jan. 9, 2794.—Of the Compofition and Pro-
portionof. “Sg if Bitumens and Mineral Coal: read Dec. 19,

* sh - : _ : 1795.—

» Expanfion of Water at Temperatures below 42 Degrees. 355

1795-—Synoptical View of the State of the Weather in Dub-
lin: read Jan. 9, 1796.—Thoughts on Magnetifm: read
March 19, 796.—On the Primitive State of the Globe, and
its fubfequent Cataftrophe : read Nov. 19, 1796.—Synopti-
cal View of the State of the Weather at Dublin in the Year
1796.—Synoptical View of the State of the Weather at Dub-
lin in the Year 1797.—Additional Obfervations on the Pro-
portion of real Acid in the three antient known Mineral Acids,
and on the Ingredients in various Neutral Salts and other
Compounds: read Dec. 16, 1797.—Eflay on Human Li-
berty : read July 28, 1798.—Synoptical View of the State of
the Weather at Dublin in the Year 1798.—Synoptical View
of the State of the Weather at Dublin in the Year 1799.—
Obfervations‘on the Proofs of the Huttonian Theory of the
Earth, adduced by Sir James Hall: read Feb. 8, 1800.—An
Mlufration and Confirmation of fome Faéts mentioned in an
Effay on the Primitive State of the Globe: read May 5,
1800.—An Effay on the Declivities of Mountains: read
April 28, 1800.—Of Chemical and Mineralogical Nomen-
clature : read March 24, 1800.—Remarks on fome Sceptical
Pofitions in Mr. Hume’s Inquiry concerning the Human
Underftanding, and his Treatife of Human Nature: read -
Oétober 20, 1800.—Synoptical View of the State of the
Weather at Dublin in the Year 1800.—Of the Variations
of the Atmofphere: read May 11, 1801.—Synoptical View
of the State of the Weather at Dublin in the Year 1801.
Mr; Kirwan is alfo the author of the following works : Effay
on Phlogifton ; Elements of Mineralogy, 2 vols. ; Geological
Effays; Effay on the Analyfis of Mineral Waters; and

- (in the prefent volume) A Reply to Mr, Playfair’s Reflections

on Mr, Kirwan’s Refutation of the, Huttonian Theory of the
Earth ; and an Illuftration and Confirmation of fome Facts
mentioned in an Eflay on the Primitive State of the Globe.

—

LX. Obfervations on the Law of the Expanfion of Water at
Temperatures below 42°; extraéted from a Paper on the
Power of Fluids to condu&t Heat, By Jounx DALtTon*.

My firft attempt was to afcertain the precife degree of

cold at which water ceafes to be further condenfed, and like-

wife how much it expands in cooling below that degree to

the temperature of freezing, or 32°... For this purpofe I tak

a thermometer tube, fuch as wou have given a fcale of 10
* From Yournals of the’Roval Inflitution of Great Britain,

Z2 jachys

356 Expanfion of Water at Temperatures below 42 Degrees.

inches with mercury from 32° to 212°, and filled -it with
‘pure water. I then graduated it by an accurate mercurial
_ithermomieter,’ putting them together into-a‘bafon filled with
water of various degrees of heat, and ftirring it occafionally.
As it is well known ‘that water does not expand in propor-
tion to its heat, it:does not therefore afford a thermometric
{cale of equal parts, like quickfilver.
‘From repeated trials agreeing in the refult, Ifind that the
water thermometer is.at the loweft point of ‘the fcale it is
capable of, that is, water is of the greateft denfity, at 421° of
ithe mercurial thermometer. From 41° to 44° inclufively
‘the variation is fo {mall as to be juft perceptible on the {cale;
~-but above or below: thofe degrees the expanfion has an in=
»ereafing ratio, and:at'32° it amounts to 1-8th of an inch, or
‘about -4.th part of the whole expanfion from 421° to 212°, or
‘boiling heat. During the inveftigation of this fubjeét, my at-
-tention was arrefted by the circumftance, that the expanfion of
water was the fame for any number of degrees from the point
of greateft condenfation, no matter whether above or below
it: thus, I found that 32°, which are 104 ° below the point of
‘greateft denfity, agreed exactly with 53°, which are 103°
‘above the faid point; and fo did all the intermediate degrees on
‘both fides. Confequently, when the water thermometer ftood
sat 53°, it was impoflible to fay, without a knowledge of other
circumftances, whether its temperature was really 53° or 32°.
Recolleéting fome experiments of Dr, Blagden in the Philo-
fophical Tranfaétions, from which it appears that water was
cooled down to 21° or 22° without freezing, I was curious to
fee how far this law of expanfion would continue below the
freezing point, previoufly to the congelation: of the water,»
and therefore ventured to put the water thermometer in-
‘to a mixture of fnow and falt, about 25° below the freez-
ing point, expecting the bulb to be burft when the fudden
congelation took place. After taking it out of a mixture of
fnow and water, where it-{tood at 32° (that is 53° per fcale),
_f immerfed it into the cold mixture; when -it rofe, at -firft
-flowly, but increafing in velocity, it paffed.60°, 70°, and, was
going up towards 80°, when I took it out to fee if there,was
any ice in the bulb—but it remained perfectly tranfparent.
[ immerfed it again and raifed it to 75° per fcale, when in
an inftant it darted up to 128°; and that moment taking it
out, the bulb appeared white and opaque, the water within
being frozen. Fortunately it was not burft; aud the liquid
which was raifed thus to the top of the feale was not thrown
‘out, though the tube was unfealed. Upon applying the
hand, the ice was melted, and the liquid refumed its isp
) is

Remarks on certain Properties of Barytes, 357

This: experiment was repeated and varied, at the expenfe of
feveral thermometer bulbs; and it appeared that water may,
be cooled down in fuch circumftances, not only to 21°, but

to 5 or 6°, without freezing, and that the law. of expanfion
above mentioned obtains in every part of the fcale from 421°
to 10° or below; fo that the denfity of water at 10° is equal
to the denfity at 75°.

LXI. Remarks on certain Properties of Barytes in its Com=
bination with Mineral Acids; and on two new Salts never
- before defcribed. By J. Hume, E/g.*

From a number of experiments I have occafionally made
on barytes, but chiefly on it when combined with mineral’
acids, I have been Jed to draw fome conclufions and obferve.
phenomena, which, I believe, have hitherto been either to-
tally unknown, or fo very imperfeétly detailed, as, no doubt,
to have frequently been a fource of error. This earth, for I
am not yet difpofed to clafs it with alkalies, certainly poffeffes
peculiar habitudes, or rather, when compared with thofe of
other earths and alkalies, and its own combinations com-
pared with each other, fome fingular anomalies, which I
have fever yet feen pointed out by chemical writers.
Amongft many others, the following appear the moft pro-
minent, and therefore demand firft to be noticed.

1. That fulphate of barytes is completely /c/ud/e in ful-

huric acid ; forming a faline fluid or acidulous fulphate, ana-

gous, in fome of its characters, to phofphate of lime and
many other falts, with capacity for excefs of acid; decom-
pofable by water alone, which returns it to fimple fulphate ;
and this falt never has been enumerated by any author.

2. That carbonate of barytes is alfo totally decompofed by,
and foluble in, fulphuric acid, forming, of courfe, the {ame
acidulous fulphate. Refpeéting any figure this new falt may

ut on, I have not. yet been able fully to determine; but [
rongly fufpeét it may, under particular circumftances, be
made to cryftallize. LymnT

3. That nitrate of barytes, not in cryftals only, but even a
faturated aqueous folution, is perfectly in/oluble in nitrous
acid of the ufual {pecific gravity. .

4 That carbonate of barytes may entirely be changed inta
nitrate by nitrous acid in its concentrated tate, The converle
of this has hitherto been maintained.

* Communicated by the Author,

5. That

358 Remarks on certain Properties of Barytes..

5. That muriate of barytes is virtually iz/olwble in mu-"
riatic acid. oO £79791

6. That carbonate of barytes may be rendered into muriate
by concentrated muriatic acid.

7. This may not appear to be, with propriety, placed after:
the others ;- it ought neverthelefs to be named, fince no au-
thor has given any account of it. It is, that fulphate of:
ftrontian has alfo a capacity for fuper-faturation; forming,
like No. 1, an acidulous fulphate in /o/ution, and decom-
pofable by water.

In feveral chemical works, written by very eminent men,
I have frequently obferved fome of the above refults very
nearly accomplithed ; and have been amazed to find fuch
palpable truths had efcaped their notice: yet, on a careful
examination of the context, I confefs, I could never find a
fingle proof that any one of thefe peculiarities of barytes has
been known to the full extent as above detailed. In refpeé to
No, 1, there is no mention of an acidulous fulphate nor of
fluidity, in an eflay, where I expected to find it, written in
1790 by C. Fourcroy*. Jt may alfo be remarked, that in
a more modern work by the fame very excellent chemift,
{peaking of fulphate of barytes, he expreffes himfelf thus:
<* I] parait cependant diffoluble par des moyens que la nature
nous cache encore, puifqu’il eft vifiblement criftallifé par
Veau. On ne peut pas le faire criftallifer artificiellementt.”
The fame author had affirmed the perfeét infolubility of car-
bonate of barytes in nitrous (or nitric, for it is not yet de-
cided) acid: ** L’acide nitrique Je plus concentré n’a abfo-
Jument aucune aétion fur le carbonate de barite natif en mor-
ceau, ce fel y refte intact abfolument comme dans I’éau f.”
This is quite contrary to the refult of my experiments, even
with little more heat being employed than the common at-
mofpheric temperature. Indeed, regarding the effect of mi-
neral acids upon the native carbonate of witherite, for it
would be unfair, in this place, to fpeak of artificial carbonate,
the fame author fums up his opinion in one fentence: ‘ Que
Jes acides ne |’attaquent point en maffe, et lorfqu’ ils font con-
centrés §.”” Since no part of this analyfis has yet been re-

* * Analy'e de Carbonate de Baryte natif, &c. § 3.

+ Syfteme des Conn, Chimique.—*‘ It, however, appears to be foluble
by means which nature fill conceals from us, fince it 1s evidently cryftal-
Yized by water. It cannot be made to cryftallize artificially.”

Ibid... “ The moft highly concentrated nitric acid has abfolutely no
a€tion on native carbonate of barytes in bits. This falt remains in it ab-
folutely unattacked, as in water,”

§ Analyfe, &c. § 4.—<* That the acids do not attack it in a mafs, and
when they are concentrated.”
bncinen tap” tracted,

Utility of Pruffiate of Copper as a Pigment. 359

tracted,. but, on the contrary, if poflible, more completely
confirmed by the author’s writings fince that period, I have
been lefs fcrupulous in applying thefe quotations to my pur-
pofe. Though another author has, in one folitary fentcnce,
apparently flatly contradicted C. Fourcroy, yet, on a clofer
infpeétion of the work, (ade édition confid:rablement aug-
mente, which I fhould call a herd edition, it does not appear
that any one of thefe habitudes or anomalies has been clearly
demonttrated to exift. The fentence is, to. fay no more of
it, evidently conditional, and no mention made either of con,
centration or dilution: ‘*'Tous les acides minéraux decom-
pofent ce fel,” (meaning carbonate de barite.*.) But my
doubts were completely removed, at leaft refpecting what I
have ftated at Nos. 3 and 4, when I.read a whole page t+,
where we find detailed a moft circuitous procefs for purifying
nitrous acid by litharge and nitrate of filver.

I purpofely forbear to mention any method I purfued to
accomplifh each combination; as it appears*to me to be
within the limits of the meaneft capacity, and obvious to
every chemift to obtain the fame refults. ;
No. 108, Long Acre,

January 24, 1803.

LXII. On the Utility of Pruffiate of Copperas a Pigment,
By Cuarres Harcuett, Efg. £.R.S.t

r
Tue accidental difcovery made by Diefbach of the pig-
ment called Berlin or Pruffian blue, about the year 1710,
and which afterwards \was publifhed) by Woodward in the
Philofophical Tranfactions for 1724, was foon adopted by
artifts and manufaéturers, fo that in’a thort time the great
utility of this colour was completely eftablifhed : it is there-
fore remarkable, that but little attention has been fubfequently
paid to the colorific properties of the other metallic pruttiates.
_The experiments made by Mr, Brown with the pruffic lix-
iyium; on various metallic folutions do not merit particular -
attention, as the refults evidently fhow that a very large por-
tion of the alkali remained unfaturated with pruffic acid, and
thus the effects appeared different when the lixivium was pre-
pared with blood or with mufele §.
Bergman has, however, more accurately examined the pro-

* Analyfe, &c. § 7.—“ All the mineral acids decompofe this falt.””
4 Manuel d'un Cours de Chimie, La Grange.

t From Journals of the Royal Inftitution of Great Britain,

§ Philofophical Tranfaétions 34 P+ 17:

4 perties

360 Royal Society of London.

perties of metallic: precipitates, (Opufcula, tom. ii, p. 385),
and efpecially notices the various colours of the pruffiates ;
but neither he nor any other chemift, as’ far as I am ac-
quainted, has pointed out to artifts the utility of pruffiate of
copper as a pigment. During fome late experiments, I was
much ftruck with the beauty of this precipitate, and was
therefore induced to make feveral trials of it as a paint: the
refults exceeded my moft fanguine expectations. I after-
wards prepared a large quantity, which-at my requeft feveral
ean (particularly B. Welt, efq. P.R.A., John Trum-

ull, efq., and fir H. C. Englefield,) were fo obliging as to try
in oil, and in water ; and I have had the fatisfaction to learn,
that in beauty and intenfity it furpaffes every brown pdint
now in ufe, with the additional advantage, that, by reafon of
its purple tint, it forms with white various fhades of bloom of
lilac colour, which do not! appear liable to fade like thofé
which are formed by means of lake.

The pruffiates obtained from acetite, fulphate, nitrate, and
muriate of copper, are all very beautiful; but the fineft and
deepeft colour is afforded by the muriate. I have found alfo
that pruffiate of lime can be better depended upon for this
purpofe than pruffiate of potafh. The beft mode, therefore,
of forming this pigment, is to take green muriate of copper,
diluted with about ten parts of diftilled or rain water, and to
pour in pruffiate of lime until the whole is precipitated: thé
pruffiate of copper is then to be well wafhed with cold water
on the filter, and to be dried without heat.

LXIII. Proceedings of Learned Societies.
.7 ;
ROYAL SOCIETY OF LONDON.

An account of a journey to the fummit of Whararai, 2
mountain in the ifland of Owhyhee, by Mr. Archibald
Menzies, naturalift on board the Difcovery, captain Van-
couver, was read on the gth and 16th of December. y
~ In January 1799, the Difcovery, being ftationed in Ka-
rakakooa bay, Mr. Menzies was defirous of making a bota-
nical excurfion into the ifland of Owhyhee, in company with
fome other'gentlemen of the expedition, and, in particular,
of afcending a conical mountain in the neighbourhood, called
‘Whararai. For this purpofe he was furnifhed with a nume-
rous company of attendants by the king of the ifland, under
the command of one of the chiefs, who was made refponfible
for his fafety, and for his perfeét accommodation with pro-.
vifions of all kinds, and who executed his tafk with as much

| fidelity

Royal Society of London. | 365

fidélity a the whole troop performed their labours with ala-
crity.. Mr. Menzies had a portable. barometer of. a fimple
conftruction, by which he afcertained the height of different
places as accurately as the time would allow. The ifland
appeared to’ be in general in a ftate of high cultivation: the
provifions for the journey confifled of live hogs, poultry, dried
fifth, yams, and cocoa-nuts, in quantities that loaded more
than twenty men, They left the fea-fide the 17th of Janu-
ary, after coming by water to the foot of the mountain, the
barometer ftanding at 3o"10, the thermometer at 81°, at
noon. The road was through lava and other volcanic pro-
dutions for about three miles: here the plantations of bread-
fruit trees began, and the country was fertile and pleafant s
the night was paffed in the uppermoft village, confifting of a
few feattered huts. Beyond this was a thick foreft, fkirted
by fruitful plantations of bananas and plantains: about three
miles within the foreft, the elevation appeared te be 2600 feet
above the fea. The thermometer was 59°, at noon. The
natives conftruéted a number of fmall huts, which afforded
fhelter to the whole party for the night at the upper extre-
mity of the foreft, Here the thermoimeter was at 58°, in
the evening: the uniformity of temperature at heights confi-
derably denen Mr. Menzies attributes to the fhelter of the
foreft, and the evaporation from the trees. But the next
morning the thermometer was at 43°. The. fummit of the
mountain was rugged and barren: Mr. Menzies arrived at it
in a few hours from the laft ftation. It afforded a very ex-
teinfive view of the ifland, although parts of it were hidden
by clouds: its moft confpicuous features were two other
mountains, of which the fummits are covered with perpetual
fnow, bearing E.N.E. and S.E. by E. of Whararai. On
this hill there is a very deep crater of a volcano, with afhes
and cinders appearing quitc frefh: the natives confider it as
the habitation of evil fpirits, whom: they attempt to pacify
by offerings of various kinds. The party of travellers {pent
the whole of this and the following day on the mountains
and paffed the night in caverns thatched with plantain leaves;
and ftrewed with grafs and mats for the occafion. The fo-
phora tetraptera was in flower, as a frnall fhrub ; in the lower
parts of the ifland it becomes a tree, of which the natives
make their fpears, and which takes a fine olith. The do-
dona vifeofa thrived on the fummit of the bil and a fmall
fhrubby geranium was found there. The height appeared to
be 85c0 feet above the fea, The thermometer was lower at
fun-fet than at feven in the morning. .

Mr. Menzies défeended on the fouth-eatt fide of the ml

an

362 Royal Socicly of Edinbungh:

and arrived in the afternoon at a deep cavern, where he paffed:

the night. Hence he made a fruitlefs attempt to afeend the
fnow-clad mountain, on the other fide of the valley, in which
the natives accompanied him with the greateft reluétance :

the fame cavern received him the following night. The.

centre of the ifland between the three mountains is barren
and uninhabited: it appears to be elevated about 5000 feet
above the fea. Returning towards the ihore, the party ar-
rived the next evening at a village nine or ten miles from:
Karakakooa bay, furrounded by fields and plantations in the
higheft poffible ftate of cultivation; its elevation appeared to
be about 2000 feet. Here they were entertained by an ex-
hibition of much grace and great activity in the performance
of a female dancer belonging to a {trolling party. The next
day was the Jaft of the excurfion; and the natives were dif-
miffed with rewards of knives, files, {ciffars, looking-glaffes,
and tape, of which a fmall portion was furrendered by each»
to the king. The barometer now ftood at 30°12, and the
thermometer at 74°.

On the 13th of January the Society refumed its fittings
after the Chriftmas holidays. An interefting paper, by
Charles Hatchett, efq. on the alloying of metals, was read
on that evening, and continued on the evening of the 23d.
It refults from his experiments that platina fhould not be
employed as an alloy for gold, as it makes the gold affume a
white colour. A number of experiments were made. with
pieces of gold coin, to afcertain the effects of the excels of
motions fimilar to what they experience by rubbing in the
pocket, and by being tran{ported from one place to another.
By thefe it was found, that copper in the proportion of 1-12th
was the beft alloy -for gold; and that the. deficiency found of
Jate in the gold coin was not owing to the wear of circulation;
as, ina quantity of guineas rather loofely packed, and fent to
fome diftance by the coach, the wear was all upon a few, and
on thofe the impreffion was quite obliterated: yet they were
not found much deficient in weight, the work being by the
action preffed in, and not:as it were filed off.

ROYAL SOCIETY OF EDINBURGH.

This learned body has publithed the fecond part of the fifth
volume of. its Tranfaétions, which prefents the following
papers:—Remarks on a mixed Species of Evidence in Mat;
ters of Hiftory; with an Examination of a new Hiftorical
Hypothefis in. the Mémoires, pour la Vie de Petrargue: by
the Abbé de Sade: by. Alexander Frafer Tytler, efq.—De-
feription of an Extra-uterine Foetus; by Mr, Thomas feliz

zard,

a

Royal Society of Gattingen, Sec, 363

zard.—Meteorological Abftract for ‘the’ Yeats 179%, 1798,
and 1799; by Mr. Playfair—A new and univerfal Solution
of Kepler’s Problem; by James Ivory, Efg.—Defcription of ©
fome Improvements in the Armis and Accoutrements of Light
Cavalry, &c.; by the Earl of Ancrum,—A new Method of
exprefling the Co-efficients of the Development of the Alge-
braic Formula (a* + 6 — 2ad cof. g’), by means of the Pe-*
rimeters of two Ellipfes, when 7 denotes the half of any odd
Number; with an Appendix, containing the res ee of
a Formula for the Rectification of any Arch of an Elhpfe: by
Mr. William Wallace.—Chemical Analyfis of an uncommon
Species of Zeolite; by Dr. Robert Kennedy.

ROYAL SOCIETY OF GOTTINGEN,

‘The following prize queftion has been propofed for the
year 1804:

As many obfervations and theories refpeéting the nature,
principles, and laws of atmofpheric phenomena, which if
fubjeéted to proof and more accurately known might be of
great importance and utility in improving the prefent fyfem
of meteorology, are contained in the works of the old and
modern naturalifts of the 16th century, the Society requires
a hiftory of meteorology from the time of the Greeks
and Romans to the prefent period, drawn from authentic
fources, and materials felected with critical attention to the
objec in view. The prize will be 50 ducats, and the papers
muft be tranfmitted to the fociety before the month of Sep-
tember of the above year. :

LXIV. Intelligence and Mifcellaneous Articles.

FROM PROFESSOR PICTET.
P © Paris, January 1, 1803.

ROFESSOR PICTET prefents ‘his moft fincere refpeéts
to Mr. Tilloch, and embraces the opportunity of a friend to
fend him one or two communications, which may prove in-
terefting.

In the fitting of the National Inftitute of December 29, a
letter was a from M. Mollet, profeflur of natural philo-
fophy at Lyons, in which he announced two faéts which
appear to be new. The firft is the appearance of a {mall
light in the air which furrounds the orifice of an ye

when

364 ! Galvanifie.

when difcharged in the dark. This experiment does not! al=
ways fueceed ; and the caufe of the differences: obferved! in
this refpe@ i$ not yet known.

The fecond fact is the inflammation of any combuftible
tnattér, fuch as'a fmall bit of liner rolled’ up, when put inte
the narrow catia) in which the lower extremity of a pump
for condenfing the dir generally terminates. Two or three
firokes'of the pifton are fufficient to inflame it, according as
the current of air produced is more or lefs rapid.

Tn the fame fitting M. Seguin concluded a memoir, which
he had announced in the preceding, on the difcovery he pre-
tends to have made of a new febrifuge principle, abfolutely
different from any of thofe before employed with greater or
lefs fuccefs. He confiders it as much fuperior to cinchona,
on account of the certainty of its effects, and the facility with
which it can be procured. This febrifuge is nething elfe
than gelaiine, or common ftrong elie. He purifies it, mixes
it wth a little fugar and orange flower water, and rolls it out
into large cakes, which he cuts into faye!! squares of the fize
of an inch, weighing about a gros. Tine dofe is from two
gfos to thirty-two, according * the age and circumftances
of the patient. It is diffolved in water in fuch a manner
that the beverage retains a confiderable degree of confitt«
ence ; and it is fwallowed at once when the fit comes on. The
fame thing is repeated at the néxt fit, and it is feldom necef-
fary to take a third.

The author has mentioned a titimber of perforis to give
tefiimony of the fuccefs of this remedy, all from the indivi-
duals who depend’on his vaft eftablif{hments of tanning and
agriculture. ‘

The Inftitute has appointed a commiffion, compofed of
Berthollet, Fourcroy, Des Effarts, and Portal, to examine
the meioir, and give in @ report On it after repeating the
experiments. |

M. Seguin has atifdunéed 4 feries of memoirs, in which
he fays,he will develop the whole theory of fever, deter-
mine what is the febrile! primciplé properly fo called, and
what is the mode of aétion 6f febrifuge medicines. The re-
fulis are waited for with a mixture of impatience and doubt.

GALVANISM.

Proféffor Aldini repeated his experiments on Galvanifin at
thé Anatomical Theatre, St. Thomas’s Hofpital, during the
Jatt month. As the profeffor does not, fpeak the Englith
language, Mr. Aftley Cooper explained to. the gentlemen
prefent. The Galvanic troughs, confifting of 129 ne of

ilver

Galvanifm. 355
filver,and zinc plates, of twolinches fquare, with the metallic
communications, were under the direction of Mr. Pepys jun.

The firft feries of experiments avas.on frogs. The head
being fevered, the {ciatic nerves and the whole of the mufcles
of the thighs and:legs were laid bare; a portionlof the verte-
br was cut away between the two nerves, leaving a fmall
portion as a holding part. >

Ep. T. The prepared limbs being held: by: the portion: of
the vertebrze, the mufcular part of the thigh or knee was
brought by the operator in :contaét with the nerves. .,Con-
tractions inftantly took plage without any metallic commu-
nication.

Exp. U. Two prepared frogs were laid on the-furface of a.
dry earthen plate, the oppofite knees and the vertebres
commurnicating ;.as foon.as a metallic are was made by a
bow of wire, touching the nerve and mufcle of one of the
frogs, violent contractions took placein both,

Exp. Ill. Three prepared frogs »were Jaid. in the fame
order as in Exp. Il, only the parts of .the.animal were not
in contact, except by a itreak of water drawn by the finger
from one to the other acrofs the plate. As foon as a
metallic communication was made.between the. nerve and
mufcle of one, all the three were thrown into motion, and
at the fame inftant. -If glafs: bars or metallic ones witha
fmall portion of wax on one end are ufed, no contraétions
are excited. r

Exp. WV. ‘Aprepared frog being: held-by the foot and a
portion of the vertebra, andthe other foot being brought. in
contact with a filver waiter, fuch violent contractions were
excited as to caufe the limb apparently.to leap along the plate.

Exp. V. ‘The operator having hold.of the feet of a pre-
pared frog with one hand, and by vetted hands communicat-
ing with three perfons or more, the laft perfon completed the
circle by touching the vertebre ; in doing which contraction
inftantly took place. ery! he Ta

Exp. VI. Twovprepared frogs being laid in the order be-
fore mentionéd on an.eartben plate,-a third was laid between
them reverfed, the toes touching the vertebre of the two.
On a metallic communication being made, the two outward
ones violently contracted, without any fenfible effect on the
middle one, though itferved as the conductor to one.

The fecond feries was on a decapitated dog, in which the
troughs were made by a flexible metallic Conductor to com-
municate with the defired/part. __ ;

Exp. VII. A wire of tin-communicating with one end of
the trough being introduced into the reétum of the animal,
the feadt being placed againft the fevyeted trunk, the commu.

nication

366 Galvanifm.

nication was made into the ear by a wetted wire, or flexible
conduétor, joining the oppofite end of the troughs. The con-
traétions were fo violent as to throw the animal forward on
the table.

_Exp. VIII. The communications were exactly as in the
lafl experiment, but the head was feparated about fix inches
from the trunk, and only communicated by the moifture on
the table. On forming the circle, the contractions were
nearly as before.

Exp. 1X. The head being removed, the communication
was made with the fpinal marrow; upon which the intercoftal
mufcles were excited fufficiently to exfpire and infpire the at-
mofpheric air with fuch force, as to blow out a lighted taper.

Exp. X. Rabbits which had been decapitated exhibited
feveral of the before-mentioned phenomena. Two trunks or
two heads placed together experienced contraCtions on the
communication being made.

Exp. XI. A portion of the diaphragm being laid on an
earthen plate, was fubject to contraction on the communi-=
cation being made.

Exp. X11. The heart was not fubje& to contraétion by the
Galvanic fhock; but was affected mechanically, as it ufually
is by glafs, refin, or any infulating pointed body.

Exp. XIII. Galvanic attraction was made fenfible by the
operator holding a prepared frog by its feet, placing the other
hand on the fpinal marrow of the dog, and bringing the
fciatic nerves of the frog nearly in contaét with the expofed
ribs of the dog: the nerves were inftantly attracted, and
contraction took place. )

Exp. X1V. The contration of the pupil of the eye, by

connecting the optic nerve with one end of the pile and
touching the iris with the other conduétor, was fhown. This
experiment was propofed by Mr. Babington.
_. The furgeons and pupils of Guy’s and St. Thomas’s Hof-
pital very handfomely prefented the profeffor with a gold
medal*, as an acknowledgement of his attention and appli-
cation in elucidating feveral of thefe compound experiments
to their complete fatisfaétion. —

* On one fide are the arms of Guy’s and St. Thomas’s Hofpital ; on
the other-is the following infeription, furrounded with raifed oak leaves:

* +» Johanni Aldino,
Praclaro Phyfico,
> 5 Digno Galvani Nepoti,
— Recens Experimentis co:nmonftratis,
Profeifores et Scholares
Nofocom. St. Thome et Guy. 4

Libenter perfolvunt.

_ Mpcccsit. Londini. |

The |

:
4

Galvanifm. 3647

* The following account of fome experiments‘on' a human
fubject we copy from the newfpapers : (hiy

* The body of Forfter, who was executed on Monday the
17th of January for murder, was conveyed to a houfe not far
diftant, where it was fubjeSted to'the Galvanic procefs by
profeffor Aldini, under the infpe&tion of Mr. Keate, Mr.
Carpue, and feveral other profeffional gentlemen. M. Aldini
fhowed the eminent and fuperior powers of Galvanifm to be
far beyond any other ftimulant in nature, On the firft’ap-
plication of the procefs to the face, the jaw of the deceafed
criminal began to quiver, the adjoining mufcles were horribly
contorted,’ and one eye was actually opened. In the fubfe-
quent part of the procefs, the right hand was raifed and
clenched, and the legs and thighs were fet in motion. It
appeared to the uninformed part of the by-ftanders'as if the
wretched man was on the eve of being reftored to life. This,
however,-was impoffible, as feveral-of- his friends, who were
under the fcaffold, had violently pulled his legs, in order to
put a more fpeedy termination to his fufferings. The expe-
riment, in fact, was of a better ufe and tendency. Its object
was to fhow the excitability of the human frame, when this
‘animal ele&tricity is duly applied. In cafes of drowning or
fuffocation, it promifes to be of the utmoft ufe, by reviving
the aétion of the lungs, and thereby rekindling the expiring
fpark of vitality. In‘cafes of apoplexy, or diforders of the
head, it offers alfo moft encouraging profpeéts for the benefit
of mankind. | The profeffor, we underftand, has made ufe of
Galvanifm alfo in feveral cafes of infanity, and with complete
fuccefs, It is the opinion of the firft medical men, that this
difcovery, if rightly managed and duly profecuted, cannot
fail to be of great, and perhaps, as yet, unforefeen utility.”

To render the preceding account more interefting, we fhall
1 the following, either new, or not bea rac known,
1. Taking the ceffation of excitability to the Galvanic fti-
-mulus as the criterion of life, the heart is not the u/timum
but the primum moriens; for, while the mufcles of the limbs
were excited to ftrong contra¢tions for even 7 hours’ apparent
death by fufpenfion of a hot-blooded animal, the heart was
utterly incapable of being excited to action, either by applying
the extremity of the metallic are to the furface or to the in-
“terior of this organ.

2. The lungs were equally inexcitable as the heart.

3. Not only were the mufcles, but the fkin and cellular
membrane, exeited to aétion by the Galvanic fiimulus. i.
” 4. The

368 Galvanifm,

4. The.contractions of the mufcles were excited by the
metallic arc or wire applied to the nerves fupplying fuch
mufcles; but the nerves themfelyes. were not affected, not
eyen the largeft nerve of the human body, the {ciatic nerve.

5. Motion or raifing up of the arm was produced (as if by
volition) by the Galvanic ftimulus.

6. A milky or coagulated matter was formed by repeated
contractions of the mufcle in contaé&t with the copper wire,
or wire of copper plated with filver: and the fame appearance
was.feen when a plate of tin foil was interpofed, for then this
white matter was formed on this tin foil. .

7. (When the parts ceafed to give out motion, or lefs mo-

tion, the motions were renewed with augmented force, by —

wetting them with folution of fal-ammoniac.

8. It is fearcely. meceflary to remark, that the Galyanic fti-
mulus excited contraétions in parts which gave out no aétion
to fulphuric acid, volatile alkali, and other ftimuli,

Of the practical Ufes of Galvanifm.

The,ufes in, common life of new facts are not always im-

mediately apprehended ; fo, that, although nothing very con-
clufive,can, be faid, the prefent facts may be hereafter of great
utility. In the meanwhile we obferve :
4. That Galvanifm maybe a moft powerful aid in reftor-
ing the vital actions fufpended by fubmerfion, by fufpenfion,
&c. although it does not aét upon the lungs and heart ; but
if, at the fame time that it excites the mufcles in general, warm
oxygen gas be applied to the lungs, and frictions and the hot
bath be employed, much more may be effected than without
Galvanifm.

2. In many difeafes confifting in ceffation of aétion, the
parts may be excited to action by this new ftimulus, zf i be
duly applied. For this purpofe a machine is required which
will of itfelf, without manual affiftance, apply effectually the
Galvanic fluid: for any length of time. Such an inftrument
has been conftruéted by Mr, Cuthbertfon, and will no doubt
hereafter be as commonly ufed as our prefent electrical ma-
chines.

3. In comparing eleétricity to Galvanifm, it muft be confi-
dered, that the former aéts by its inten/ity, and the latter by
‘its paeniiy :.that the former, fo intenfe, and fufficient if pro-
perly direéted to knock a man down, fhall yet not be in guan-
tity enough to melt an iron wire or one of platina; but the
latter fhall melt thefe metals, yet fcarcely produce a fhock.

Se

@
MISCEL-

Chemical Notices. mQO 369

MISCELLANEOUS.

i. Hildebrandt, in a feries of experiments on the action of
both the carbonate and pure ammonia on copper, found no
folution take place without the prefence of atmofpheric air.
Hahnemann had afcribed the aétion to the carbonic acid ob-
tained from the air, but this he has proved is without foun-
dation. If the oxide of copper is ufed, a blue folution is pro-
duced without the admiffion of the atmofphere.

2. According to Vauquelin, the boracite called magnefio-
ealcareous borate by the French chemitts, is not a triple
compound, confifting of boracic acid, magnefia and lime.
When tranfparent and cryftallized, he finds in it none of the
latter fubftance, but only boracic acid and magnefia. When
opake, it is rendered fo by lime, not in chemical combina-
tion.

3. An analyfis of the waters of Plombiers, by Vauquelin,
gives per pint:

1 gr. 1-6th of fulphurated foda,
5-8ths of muriated foda.
2-3ds of filex. ‘
1-4th of carbonate of lime. —
1 gr. 1-12th of carbonate of foda.
1-half of animal matter. _
This animal matter is like albumen, and is only held in
folution by the foda; as an acid inftantly feparates it, and
caufes it to precipitate. .

4. Brugnatelli recommends nitric ether to be prepared in
the following way:—lInto a tubulated retort put one ounce of
fugar and two ounces of alcohol: to the retort adapt a large
receiver covered with wet cloths; fecure the joint with pafted
paper, then pour in three ounces of concentrated nitric acid

y the tubulure: ebullition takes place, and an excellent ether
of an orange colour paffes into the receiver, which will not
redden vegetable blues: as foon as the ether is all received,
nitrous gas is evolved? the receiver muft be immediately
changed. By treating the refiduary fugar with more nitric
acid, oxalic acid very pure will be obtained.

5. Mr. Dabit, in the Annales de Chimie, No. 127, gives an
account of fome experiments on the refiduum of fulphuric
ether, from which he is induced to believe, that he has dif-
eovered an acid of fulphur in a ftate of oxygenation interme-
diate between the fulphuric and fulphureous acids. As yet
he has not obtained it in a free ftate; and” he founds his

Vou. XIV. No. 56. Aa ~*» conclufions

370° Optical Improvement.—Galvani/m.

conclufions upon the phenomena prefented by its faline
compounds.

In faturating the refidaum. of ether, mixed with water,
with carbonate of lime, he obtained a folution which gave
by evaporation a falt that cryftallized in parallelopipeds,
having but little tafte, and being foluble in 1co parts of cold
water. This falt was decompofed by fulphuric acid. By the

action of oxygen gas, or of nitrous acid, it was converted -

into fulphate of lime; and, by being heated with charcoal,
it gave a fulphuret of lime. .

When it was mixed with a folution of carbonate of pot-
afh, foda, or ammoniac, a double decompofition took place,
and the ftronger acid combined with the alkalies.

Mr, Dabit has noticed fome of the properties of its alka-
line combinations, which are extremely analogous to thofe
of the fulphites, He propofes to call the acid the oxygenated
fulphureous acid, But the application of the name will moft
probably be.generally confidered as premature; and new
charaéters will be required to diftinguifh it from the ful-
phureous acid, before its exiftence as a peculiar body can be
implicitly admitted.

6. Dr. Benzenberg, in an effay on the improvement of
object glaffes for telefecies*, warmly recommends that the
glafs be fuffered to cool in the pots without ftirring, and
that the mals be then divided in a horizontal direction, fo
that the variation of denfity may be regular, and then, by a
proper form of the glaffes, the errors of refraction may be
corrected. The idea.is not new, but it does not appear to
have been carried into practice. Dr. Benzenberg confiders
achromatic telefcopes as promifing much more than reflec-
tors, and thinks that they intercept much lefs light.

4. Mr. Sprenger of Jever gives an account} of his method |

of adminiftering Galvanic electricity in cafes of deafnefs. A
fmall ball is applied to the external orifice of the ear, anda
much larger one is held in the patient’s hand; the commu-
nication is then formed and interrupted alternately by means
of machinery, once in every fecond, for about four minutes
daily, for a fortnight or more. He afferts that he has thus
reftored the \enfe of hearing to forty-fiye perfons, and to four
‘of them that of fmell alfo. All who were completely deaf
experienced relief, almoft without exception; but a partial
deafnefs did not appear to receive the fame benefit. The ear
was filled with wool, to avoid taking cold. The degree of
advantage obtained was e(timated by an inftrument invented

* Gilbert’s Annals. + Ibid.

Artificial Cold. 371

by Profeffor Wolke, in which a hammer falls from a certain
oi of a Reach fo as to ftrike an elaftic plate with a ve-
ocity capable of precife determination. Thefe experiments
relate to a fubject fo important that they muft not be pafled
unnoticed, however improbable it may appear that Galvanic
ele&tricity fhould have any material advantage over electricity
otherwife excited, and however we may be difpofed to believe
the report of other obfervers, that the relief is in generak in-
confiderable and only temporary.

ARTIFICIAL COLD.
Mr. Lowitz (Journal de Chimie et de Phyfique, by Van

Mons,) concludes, from various experiments on. artificial
cold, of which a particular account is to be publifhed in the
Tranfaétions of the Academy of Peterfbourg,

1. That the principal caufe of the cold produced during
the folution of falts in water, depends upon fome agency of
their water of cryftallization ; for falts deprived of this wa-
ter, inftead of producing cold, produce heat. Sai

2. Amongft the liquid acids, the muriatic acid is moft
efficacious for forming freezing mixtures; the nitrous acid
is next to it in order; and the fulphuric acid is leaft pow-
erful.

3. The liquid acids produce cold only becaufe they oc-
eafion a quick folution of the fnow, or falt, of the freezing
mixture.

4. Cauftic potafh and the muriate of lime furpafs very
much, as cooling agents, the acids and the other faline fub-
ftances. |

5. The beft proportion of the mixture of fnow and muriate
of lime, is two parts of the firft to three parts of the laft,
mixed as accurately as poflible.

6. Five pounds of muriate of lime are fufficient to freeze
thirty-five pounds of mercury.

7. The deliquefcent falts are much more proper for pro-
ducing ebld than the efflorefcent falts, }

8. That the deliquefcent falts may produce the highelt
poffible degree of cold, it is neceflary that they contain the
greateft poflible quantity of water of cryftallization ; and that
they be ufed in dae powder.

. The fnow employed thould be that: which has newly
fallen, light and dry; and the experiments fhould be made
at the commencement of a froft, and not during a thaw.

10. It appears that the fuperiority of the deliquefcent
falts to the acids is owing to the circumflance of their be-

Aa2, coming

342 Preferving Animal Subftances.—Humboldt’s Travels.
‘coming fluid at the fanie time that they caufe the fnow ‘to
“diffélye. |! 0 ss
* ‘rf. Cauftic potafh and muriate of lime poffefs, among
other advantages, that of being eafily reftored, unaltered, to
“their folid ftate, after an experiment, by evaporation. =~

} PRESERVING ANIMAL SUBSTANCES..

Mr: Chauffier employs, for preferving animal matters from
putrefaction, a folution of oxygenated muriate of mercury,
kept conftantly in a ftate of faturation. The preparations
remain immerfed in it for a certain number of days; and,
after they are thoroughly impregnated with it, may be dried
‘by expofure to light and air. After the procefs, they are no
longer fufceptible of being eafily decompofed ; they preferve
their form, become poffeffed of a great degree of hardnefs,
and are not fubjeé to the attacks of infects.

HUMBOLDT’S. TRAVELS.

The Berlinifche Monat/chreft,'a journal publithed monthly
‘at Berlin, ‘contains an interefting extra€t of a letter from
‘M. Alexander von Humboldt, in which he gives an account
-of the progréfs of his travels through South America.” It is.
written from Contreras, near Ibagua in New Grenada. Be-
fore he left Carthagena he ‘paid a vifit to the foreit of Tur-
baco, celebrated: for the. fize of its trees: fome of them are
eight feet in diameter, and are of the kind named: cavanif-
lefia mocondo, before obferved by Jacquin, who travelled in the
“time of Francis I. -M. von Humboldt, who had propofed to.
go to Peru, could not refiit the defire he entertained of pro-
“ceeding to Santa-Pé-de-Bajota to fee the celebrated botanift

“Mutis, 72°years of ace, and one of the friends of Linnzus. °
Thus, inftead of proceeding by fea to Guayaquil, which
‘was much more convenient, he purfued the route to Quito
by land throuzh Santa-Fé. He firft navigated, for forty-five
~days, along the river De la Madelaine, amidft the moft dread- _
ful tempefts and the moft dangerous cataraéts. During this
part of his journey he conftru¢ted a topographieal chart of
the country on four folio fleets, a copy of which was kept
by the viceroy. When he arrived at Honda, in five degrees
north latitude, he vifited the mines of Mariquita and Sainte-
Anne. In that country he found confiderable plantations of
cinnamon and nutmeg-trees; and whole forefts of the tree
which furnifhes cinchona, and of the almond-tree, called by

botanifts caryocar amygdaliferum.

M. von Humboldt was at that time accompanied by a
young

7

Salts of Irons 393°

youtg Frenchman named; Defieux},towhom the Spanit,
government had entrufled the care of-thefe, plantations. Our
travellers at length reached the entrance of the Cordilleras,
(/a Bocca del Monte), clinvbed up the firft eminences, and
came to the plain of Bajota, one, of,the higheft of the globe.
This plain was) fermerly:a lake, eontdining.a furface of 32
{quaré leagues: inthe middle of itis fituatedithe town of Santa-
Fé... M. von Humboldt was received hete.as if,in triumph :,
fixty perfons on horfehack came to meet him; and the vene-.
rable Mutis had prepared a houfe for him, near ,to),his own.
The:king of Spain devotes 10,000 piaftres. per annum to this,
botanical, eftablithment. » For fifteen years pat, thirty, draft{-;
men have been employed im it under the direction; of Mutis.
They, have. executed 3000 ‘drawings. in. folio, which, are,
finithed with all the delicacy of miniature painting... M. von,
Humboldt could compare the botanical collection of Don,
J. Celefiino Mutis;only to!that of SirJofeph Banks. M. von
Humboldt meafured.the altitude of the mountains: which
farround Santa-Fé,:feveral of, which, rife to, the, hefght of
2000-and 2400;toWles: -From Santa-Fé; hewas to proceed
to Quito, ‘and. thence to Limia. ..He was, to be at Acapulco,
in the month of May laft year, and, after travelling through
Mexico, he was to return to Europe by the Philippines and
the Cape of Good Hope. Such a journey, undertaken by fo
_ enlightened a man, promifes the happieft refults to {cience,

SALTS OF IRON*,

The fulphate, muriate, and acetite of iron, at their mini-
mum of oxidation, may be obtained in a very eafy manner
by means of the artificial fulphuret of iron. When artificial
fulphuret of iron is ated upon by muriatic acid, or fulphuric
acid in a ftate of dilution, -or acetons acid, the fulphureted
hydrogen. gas, difengaged during, the Pye of folution,
prevents, any hyper-oxygenated falt from being formed by the
action of the atmofphere; and a clear fluid, in all cafes, of a
fhade of green, is obtained, which, when freed by heat from
any fulphureted hydrogen diffolved in it, gives a perfedtly
white precipitate with the alkaline pruffiates, and is not found
to alter the colour of folution of galls,

To form the leaft oxygenated nitrate of iron, by means of
the artificial fulphuret, an acid of a fpecific gravity not greater
than 112 mutt be ufed; and the folution muft be made with-
out the affiftance of heat. After having been freed from ful-
phurated hydrogen, by being boiled for a minute or two, and

CT APF em Jou nals of the rey Inflitraion.op eat Britain.

a3 then

374 Salts of Iron.

then filtrated, it is found fimilar im its colour and phyfical
iad to the weakelt folutions of the other oxygenated
alts. Totts

When the fulphate and muriate of iron, at the minimum
of oxidation, are obtained in the folid form, by evaporation
from their folutions, ‘they appear in regular cryftals, which
in each falt are a different fhade of a very pale green colour;
their taftes are exactly fimilar, being aftringent, and leaving
in the mouth the fenfation of fweetnefs.

- The leaft’ oxygenated nitrate of iron cannot eafily be pro-
cured pure in the eryftallized (tate; for when the folution of
it is heated for ie one of time, a new arrangement of its
principles takes place ;’ portions of ‘the acid and of the water
of the foltition are decompofed ; in confequence of which
ammoniac is formed ; and an oxygenated nitrate of iron, with
excels of bafe, is depofited. + bl

» Amongft the falts of iron, at the minimum of oxidation,
T have found the muriate the moft:convenient for exhibiting
the experiments of Prouft, and in eudiometrical proceffes
with nitrous gas. It is more foluble in water than the ful-
phate, and very much more foluble in alcohol. D.

ERRATUM.
Page 82, lines 3 and 4, for “ organ of inftin@ and,” read ** organ
of inttinét of.”

Byes ‘\. INDEX

ee

- 7

INDEX To VOL. ‘XIV.

;

Acapemr of the Ujeful Sci
ences, Erfurt, 86
Academy of Sciences, Tl 89

Academy of Di ijony title: of,
| changed, x onong7
Acetite of leads. On dyeing

with, 318
Acid. Anew one, . 369
AG&ion at a diflance. A primary

law of nature, 193
Aéroftation. .. Remarks on, 337-

Aikin on Schieferfpath, 293)

Air, ftate of, in charcoal, 202
Air. \Ligtt-and heat liberated
from, 363
Agus Vapour-bath defcribed,
- 293°

Albumen aD in mineral waters,
369

Alloying of metals. On, — 362
Alphabet, antient, of the E. goptians,

ei}

difcovered, 93
Alumine fufed, . (
Aluminous fulphates. On, 275
Amalgam, native, of = On,

Aealyfi fis of ore of enim ob)
carbonate of lime, 289: of
fchieferfpath, 291: of zeolite,
310: of watersof Plombiers,369
Anatomy, g 277
Animal pe Ta preferve,

Antiquities,
Antiquarian Society, ane 93
Argental Mercury. ih
Arfenic acid, On Shing 7

Afe: cupells. Inconvenience of,

210
Afkefian Socictyy 55
A/phyxias” A cure for, 179
Affaffination, Organ of, 33

Affayi Ing. On, 213
Ajcenfion of water in’ capillary
tubes. On, 9% 194.

Aftronomical notices, 94, 174, 185
Aimofphere. On the fate of va-

pour in the, 143, 258
Atmofphere. Preflure of, 294

Attachment. Organ of, 83
Attraaion. Univerfal, 193 ; of
floating bodies, 287
Balazvin's balloon excurfion, 340
Balloons. On; 337
Baraeite, On, 369
Reaoteticiess A caufe of error in,
199

Barytes On certain properties of,

357

Barytes, pruffiate of, 272; fufed,
304, 305; on dyeing with,
318

Batavian Society of Sciences, 283
Beauford on ftones from the

' clouds, 148
Belles Lettres. Prize queftion i iby

5
Bengal. On hunting in, 319

Benzoic acid, to obtain inodo-
“rows, 331; on vapour of, whea
cooled fuddenly, §7, note.

Biography. 353

Biftre' ‘colours for glafe and ac

‘eelain, ; _
5 . Bitumeny

376

Bitumen, falt of. On, 206
Black (Dr.) fixft. fuggefted air
balloons, 338
Blacks for glafs and porcelain, 22
Blanchard’s ‘balloon improve-
ments, 340
Blaft furnace of the French
School of Mines defcribed, 69
Blavier, on {pecific gravity of
coals, 258
Bleaching. Remarkson, 178
Blow-pipe.. Au improved, 238,
2g
Blues for glafs and. porcelain, 21
Bojanus on Gall’s Craniognomic
Syftem, 77
Bombay., On Monfoons at, 328
Brain, the material organ of in-
ternal faculties;
Brogniart on vitrified colours, 17
Brown for glafs and porcelain, 19
Brugnateili on ether, . 369

Cadet on:the wax tree,
Caloric. A prize queftion, 283
Camphor. On vapoursof, 57 note
Cancer. “Remedy for,’ 285
Capillary ation. Leflie on, 193
Carbonated lime. On a variety
of, 48; analyfis of, 289
Carbonic acid gas. Change pro-
_ duced on, by eleétricity, 3505
decompofition of, by hydro-

. gen, 352
Cafia. Extrac& of, 66
Cavallo’s experiment on balloons,

gta 339
Cavallo’s work on balloons, one of
the beft, 340
Cements, various. To prepare,
Ii], 123
Champeauxx and Crefac ona ee
variety of epidote,
Gharcoal, On icantillation oe
collifion.of, 178. State. of air
< ip, 202. On makings. > 245
Charles.and Roberts’ balloon,.339
Chemical efecis. New, .. 200
Ghemifity. Prize qué@llion in, 36

. 262.

INDEX.

China. Painting on, 17
Chry/folite, (of Werner) seni

- on,

Circum/pection. Organ of, 84
Coals. Onfpecific gravity of, 258
Cobalt. Experiménts on with

cochineal, 316 .
Cochineal. Experimentson, 316
Cold, artificial. On, 370
Cologuintida, Extra& of, 66
Colours from metallic oxides,» ri
Comet. A new,

Combuftion, f{pontancous, of Fl
human body, Inftance of, 96
Compofition in painting. On, 97
Copper. Aion of ammonia on,
369

Copulation. Organ of infting
of, 82.
Cordier on argental mercury, 41
Courage. Organ of, Ato SZ
gp Syftem. Dr. Gall’s,
TT.

Creffac on epidote, 455, On car-.
‘bonated lime, ° 48

; Gunning. Organ of, 84.
Cupells. On'a new kind of, 210

Datit on an det of fuiphar, 369
Dalton on expanfion of water at

low temperatures, 355.
Dalton’s theory of the conkitu-

tion of mixed gafes, 169
Davy on falts of irony >» 373.
Dayes on painting. . 397.

Deafnefs cured by Galvanifin, »3 710
Deco&ion, .On,?- > % iG
Déelarive on tubes diodpied here
_ monious by hy drogen, Gasy 24
Diabetes Mellitus. Ong ofo1279
Difpofition in painting. Onyx Qz,
Double. refraction of rock. or
_-tal, applied to-optics, » 306

Drawing. Power. and ufefulnefs
of, ii, yeBQ
Dubamel, On cupells, 218

Dyeing» Experiments in, 316

ons
Eatt}, On the Huttonian the-

ory

Extraas, vegetable. To prepare,

Fluids, compound.

INDE”

ory of the, 3; on the primi-
” tive ftate of, 14

Eciiptic. Obliquity of, aprize .

- © queftion,

4.
Economy. A: prize queftion, 283
Ekeberg on yttria, glucine, and

tantalite, “346
EleGoral Academy, Mentz, 284
Eleétricity.. A prize queftion, 85
Elephant's head. compared with

that of the Mammoth, 228
Epidote. On a new variety of,

45

Ether, nitric. To prepare, 369
Expanfive force of vapour. Ta-
bles of, ~ 146

63

Fohrifuge principle, anew, 364
Fermentation, A prizequettion, 85
Fleuriau, on making charcoal,
245
Inftrument
propofed to determine the pro-
portion of ingredients in, 200
Food. Organ for the choice of 81
French National Inftitute,86,173,
, ew BR
Friendftip. Organ of, 83
Fuel for great beats: New, pro-
pofed, 305
Furnace. Defcription of the Three-
blaft, in the French School of
Mines, 69
Fufion. Colours fixed by, 17

Gadolinite. On, 349
Gall's (Dr.) Craniognomic Sy{-
tem, 77
Galvanic experiments, Aldini’s,
88, 191 288, 364; Giulio and
Vaffalli-Eandi’s, 89; Paris So-
ciety’s, 281
Galvanic Society, Paris, $8, 281
Galvanifm. Aldini’sexperiments,
364: applied to cure deafnefs,

34°
Garaye’s method of making ex-
tracts, 68

377
Garanerin’s balloon excurfions, 341

| Gafes, mixed. New theory of

the conftitution of, 169
Geography. A-prize queftion, 86
(Geology, = 3y 14, 280
Giefe on benzoic acid, 330
Gillet- Laumont’s fympathetic
ink, 76
Glajs, - Painting on, 17
Giafs attra&s moitture, 203
Globe. On the formation of the,

4
‘Glues. To prepare, T1g, 120

Glory. Organ of the love of, 131

Glucine. On, 346
Gravitation. A branch of a pri-
mary law of nature, 194

Greens for glafs and porcelain, 21

Hare’s improved blow-pipe, 239,
298
Hatchett on pruffiate of copper,

359
Hemlock. Extra& of, 67
Heat. To produce the greateft,
301
Henderfon on Bit-Noben, 206

Henley on the zodiac found at
Dendera, 107
Hermflaedt’s experiments in dye-
ing, 316
Hildebrandt on the a&tien of am-

monia on copper, 369
Hindoo chemifiry. On, 206
Hints to artif}s, 8c. 117

Hiftory. A prize queftion, 283
Howard, (id. Elg.) on ftones
fromthe clouds, © 49
Howard, (Luke, Efq.) on Dr.
Hutton’s theory of rain, 55
Humboldt’s travels, 372
Hume on barytes, 357
Hunting, On, . 1g
Huttonian theory of the earch.
Mr. Kirwan on,
Hution’s theory of rain. On, $5
Hydrogen gas applied to produce

founds in tubes, 24
Hydrometers. Mr. Speer on, 151,
229

Hydrometer

378
Hydrometer.” A new one pro»
pofed, 200
Hyd: oftatic Bloew-pipe. New, 238, 8,
29
Hyofcyamus. Extra of, 67
Ichneumon defcribed, 139
Zmpulfe. How it a&s, 193
Infujion of vegetables. On, 63

Ink, fympathetic. Anew, 76
Infiing. Organ of, 82
Jnwention neceflary to a painter,
Tr F 31
Tron, native, Count Bournon on,
49

Tron alloyed with fiver, 95
dron. Salts of, 373

Tronfide (Col.) on hunting, 319
Fablown/ky Society, Leiptic, 283
‘Fupanefe cement. Toprepare, 120
Fewellers’ cement, 121
Juices of plants. ‘To prepare,

in pharmacy, 63
Funiper. Extra& of, 66
Gurin's account of capillary ac-

tion, not true, 195

Kennedy on zeolite, 310
Kirwan, (Richard, Efg.) fome
account of, 353
Kirwan’s reply to Mr. Playfair’s
refleGtions on his refutation of
the Huttonian theory of Be

earth,

Kirwan on the primitive ftate %;
the globe, 14: On the {tate of
vapour fubfitting in the atmo-
{phere, 143; 251

Lalande on magnetic pole of the
earth, 249

Lambert’s (of Berlin) eftimate of

vapour in atmofphere, 255
Latent heat in water and in
fteam, 143
é. @, Qn refining, 210: On
dyeing with, 318
Learned Societies _ Proceedings
of, 84, 173, 270, 360,

Leflie on capillary a¢tion, 193

INDEX.

Liberality.’ Organ of, 136: ~
Life. Organ of the tenacity of, $t
Lime, carbonated. On a variety
of, 48: analyfis of, 289: par-
tially fufed, 304: profiiate of,
f 272
Liguorice. Extraé ee 67
Love, reciprocal, of parents and
children, Organ of, 82
Lowi'z’s experiments on artifi-
cial cold, 371

Maceration of vegetables. On, 63
Magnefia partially fufed, 304, 305
Magnetic pole of the canbe: La-

lande on, 249
Mammoth. On the, 162, 228, 332
Mathematics. Prize queftion in,

84

Medicine, 179, 209; 279, 285,
: 293, 364
Mercurial faits. Qn, 273
Mercury, argental. On, 41
Mercury. ‘Tranfit of, over the
fun, 186
Metal. A new one, 95, 346

Metals. A&tion of, on cochineal,

316

Meteors, On, 49, 148, 272
Meteorology. A prize queftion, 363
Mildnefs. Organ of, 137
Mineral waters, art patel On,
208

Moifture, cements whiich refift,
122

Molybdic acid. On dyeing with,
317

Mons on phofphuret of lime, 309
Monfoons. On the, * 328
Moral philofophy. Prize quef-
tious in, 85,86
Morczzo’s account of an ichneu-
mon, 13
Morveau’s method of determining

relative atiradions, Not accg-
rate, 199

, Moticn. How propagated, 193
Muriate of tine On dyeing
with, 318
Needle

4

Se ee ee

INDEX.

Needle fwimming on water. Caufe
of, 199
Nar<i. On double refraGtion, 306
Native iron. Count Bournon on
the origin of, 49: of Siberia,
50: of Bohemia, South Ame-
Tica, and Senegal, 51, 53, 54
Navigation. Remarks on, 328

Nitric ether. To prepare, 369
Olbers’ planet, 185
Opium. On preparing, 66

Optical inftruments, Propofedim-

_. provement of, 306

Ore of Uranium. "Analyfis of, 276

Organs, and their faculties, judged
of by their form,

Oxygen and hydrogen gas. hg
heat excited by, 238, 298

Oxygeniated muriate of mercury,
preferves animal matters, 372

Painting. On porcelain and glafs,

17
——— Mr. Dayes on, 31, 973

Parmentier on vegetable extracts,

3

Peale on the Mammoth, 162,228
Perido'e; Remarks on, 52
Perfeverance. Organof, 138
Pharmacy. On vegetable prepa-
rations in, 63
Phillips on {chieferfpath and car-
bonate of lime, 289
Phofphuret of lime. To prepare,

309

Phyfics. Prize quettions in, 85,
86, 2%3

Phyfiognomy, Remarks on, 77
Piet on meteors, 272

| Pigment. A new, 359
Plaifler for terraces, 125

Plants. T prepare the juices of
in pharmacy, 63: fubjected to
Galvani{m, go

Plants abforb moifture from the
air, — 203

Platina. Fufion of, 304

Pluyfair’s vefieEtions on Mr. Kir-
wau's refutation of the Hut-

tonian theory of the earth, re: -
plied to by Mr. Kirwan,
Plombiers, Waters of analy{ed, 369
Poppy. Extra& of, 66
Porcelain. Pairiting on, 17
Pownall (Governor) on the
mammoth, 332
Powder mills. On explofions
at, 178
Precepts and recipes for pen
&c. 117
Prize queftions, 84, 86, 283, 363
Pruffiates of barytes andiime, 272
Pruffiate of copper. Mr. Hatchett
on, 359
Purples for porcelain and aint
I
Rain. Con fiderations on Dr. Hut-
ton’s theory of, 55
Recipes for artifts, &c. 117
Reds for poréelain and glafs
painting, from gold, 18: from

Iron, 19
Refining of lead, 210; of filver,

216
Refradion, terrefirial. A curious,

176
Rice glue. To make, 120
Robs. To prepare, 66

Roberts and Charles’s balloon, 339
Rozier’s balloon, 338; his fate,

339
Rock eryftal, Double refraction
of, applied to optical eee

3

Rofe colvurs for- glafs and porce-
lain, 19
Rouge. Anew polihhing, 276
Royal Academy of Sciences, Berlin,
84, 284

R yal Society of Gottingen, 93, 363
Royal Society of Londm 173,2 is

gvo
Royal Séeicty of Edinburgh 362
Saffron, Extract of, 66

Sal ammonias. Hints refpedtingy

276
Salts, Anew ‘triple, 275: ano-
» therfnew, 370
Salt of bitumen. Ong 206

Salts

480 I Ne DSEXX 1

Salts of iron. Davy on, 373
Sauffure, on carbonic acid gas,

ele&tricity, and hydrogen < 52
Sauffure’ stableof vapourin air2 54

Schieferfpath. Analyfis of, 291;
defcription of, 293
Schmid’s table of expanfions of

moitt air, 251
Self-prefervation. Organ of the
inflin& of,. 8t
Senfés, various. Organsof, 81,
132
Senna. Extrat of, 67
Silex, fuled, 304, 305
Silver alloyed with iron, 95. On
refining, 216

Smith’s air-pump vapour-bath,

293
Snow. Formation of, illuftratsd,

note, ag y
Societies, Learned, 84, 173; 279,
360

Speer on hydrometers, 151, 9
Sporting. On, 319
Steam. A cement that will fand
againtt, : 123
‘Stones from the pious” How ard

on, 49. Beauford on, 148. Pic-
tet on, 272
Stramonium. Extra& of, 67
Strontian.. On dyeing with, 319
Sulphates. Aluminous, 275
Sulphate of foda and ammonia. A
new falt, 275
Sulphur. New acid of, 369
Sun, Attractive force of, 193
Sympathetic ink, A yellow, 76
Tamarinds, extract of,. 66
Tawlahve. A new mckah 94+ 346
Telef ope improved, 306: ‘im-
proved object glaffes for, 370
Tin, improved method of ufing
in dyeing, 318
‘Torpor of certain animals in win-
ter. On the, 87. A prize
queftion
Travels. Humboldt’s, 352
Truth. Organ of the love of, 131
Tubes rendered harmonious, by
dey eenget gas, 24

Tubes, capillary. On, 194

Tung. Sic acid, On dyeing with,
I

Turkey cement, er

Varmfb for balloons. 345
Uranium, Ore of, analyfed, 276,
Experiments on, with cochineal,
316
Vapour fubjifting in the tiene
On {tate of, 143, 251
Vaccine inoculation. New fa&s
in, 92, 184. Dr. Pearfon’s
evidence, 180. Dr. Heberden’s,

18
Vegetable extras and juices. On,
6
Vegetables abforb moifture rake
the air, 203
Vegetable wax, how collected,
263
Vinegar. Improved procefs for
making,
Violet colours for glafs and por-
celain, 18

Water. A{cenfion of, in capillary
tubes, 194. ‘Union of, with pa-
per, produces heat, 201. Ab-
forbed by vegetables from the
air, 203. Experiments on the
flowing of, 204

Water, Law of expanfion of, 3555
below a certain degree, dilates

by cold, 356
Waves. Power of, a prize quef-
tion, 283
Wax. To bleach, 266, Prepa-
rations In, 277
Wazx-tree. On the, 262
Weavil in fea bread. 'To prevent,
286,

World. On the formation of the, -

4, 14.
Wright on acroftation, 337
Yellows for glafs and porcelain,

20
Yttria earth. On, 346
Zeolite. Analyfis of, 310

Zodiac found at Dendera, Mr.
Henley’s obfervations on the,
107

END OF THE FOURTEENTH VOLUME,
» Printed by Wirxs and Taytor, Chancery-Lane.

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