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TABLE OF CONTENTS.

NUMBER LV.—JULY.

Page

Mr. W. Sturgeon on the Thermo-Magnetism of Homogeneous
Bodies; with illustrative Experiments (continued)........
Mr. J. E. Drinkwater on Simple Elimination ..............
Prof. Encke on the Solar Eclipses and Transit of Mercury over
the Sun’s Disc in 1832............ 2+ eeeeee ee ceee corres
Rev. P. Keith on the Conditions of Life (continued)
Proceedings of the Royal Society ........---.+eeeee- eure
—— Geological Society... 0 5.0. 00004. ee
Astronomical: Societys: 2)... 206.0505.
Zoological Society -.........+2..+5+-
at the Friday-Evening Meetings of the Royal
Institution of Great Britain ..........00..0.--ceeee eee
Dr. Forster’s Account of an Aérial Voyage made in a Balloon
on Saturday the 30th of April 1831
MANN. PCE) a siete Se nin ibte = mie in ain Scientist ay eloyerec nad shana
Occultations of Planets and fixed Stars by the Moon, in July
1831. Computed for Greenwich, by T. Henderson, Esq. ;
and circulated by the Astronomical Society..............
Dr. Burney’s Results of a Meteorological Journal for 1830,
kept at the Observatory of the Royal Academy, Gosport,
PUB SRS Chain b elRcts plete eh eleierel nim helm ote Mint aie sie ga 'ee
Mr. Giddy’s Extract from the Meteorological Journal kept at
ROUZADCE 555 «cis 5 ite =ainrtelern'e * Sle oil ois foie asa (ales fetter ope ete teag ote
Meteorological Observations. ......... ce.ss-seeseeeccees
Meteorological Observations made by Mr. Thompson at the
Garden of the Horticultural Society at Chiswick, near
London; by Mr. Giddy at Penzance, Dr. Burney at Gosport,
and Mr. Veall at Boston

eevee reer ee ee ee ee es ee

ee ee

NUMBER LVI.—AUGUST.

Mr. J. W. Lubbock on some Problems in Analytical Geometry.
Mr. J. Nixon’s Particulars of the Measurement, by various
Methods, of the instrumental Error of the Horizon-Sector
described in Phil. Mag. vol. lix. (continued) ........++++-
Mr. W. J. Henwood’s Notes on some recent Improvements of
the Steam-Engines in Cornwall.........-0.++eeseseeeee
Mr. J. Prideaux on Chemical Symbols and Notation ; in Reply
to Professor Whewell

Vinssus O12 019 0:09.05 00 EDO MOE » DBO 4 6 010.8

1

80

iv CONTENTS.
Page
Mr. H. J. Brooke on Poonahlite, a new Species of Mineral; on
the Identity of Zeagonite and Phillipsite, &c.; and other

MGIiepePIINDICES tiles ie aes ao ss Wath eatir asia 3 109
Rev. H. Coddington on the Theories of Achromatization, &c.

RRC COP IDEs) GTI cde sas csa'e x craic » -'ss' se eiores 112
Mr. W. Sturgeon on the Thermo-Magnetism of Homogeneous

Bodies; with illustrative Experiments.................- 116
Rev. P. Keith on the Conditions of Life............ . 124

Mr. G, Innes on the Statement in the Nautical Almanac for
1833, of the Time of Beginning of the Solar Eclipse of the
16th of July in that Year ; together with the correct Times
of that Eclipse, computed for Greenwich............ ... 135

Errata in Schumacher’s Ephemeris of the Distances of the
four Planets Venus, Mars, Jupiter, and Saturn, from the
Moon’s Centre, &c., for 1833, published by the Admiralty.. 136

Mr. S. Sharpe on the Theory of Differences .............. 137
Prof. Airy’s New Optical Experiments.............0000005 141
Proceedings of the Geological Society .................- 143
——_——-_—————- Zoological Society .................. 145
General Scientific Meeting at York—On the Rapid Flight of

Tnseataied: pnd isin.’ picts’ Late ie) 8a, I Sittin ¢ PSEC 150
Process for preparing Hydrocyanic Acid—Vanadium, a New

Br etaL oh six ron BE ee enc Aten PAC Pree A be, 151
Magnesium........ pha. tieisin, AAs lei eo. ae 152
IM: Gay-Hussacion:Oxalic Aeiditying.cv work. aia) A 153
M. H. Braconnot on Gallic and Pyrogallic Acid...... ..... 154

Mr. J. Hemming’s Analysis of Tennantite—New Patents .... 157
Occultations of Planets and Fixed Stars by the Moon, in August
1831. Computed for Greenwich, by T. Henderson, Esq.;
and circulated by the Astronomical Society—Meteorological
ROUELY BENING coals) 3 5) 4.5 a= 5 ms oats Daca hh lel aa 158

NUMBER LVII.—SEPTEMBER.

Mr. 1. J. Brooke on Isomorphism., ..5.;.. 05.24% 25. denchiaes 161
Mr. J. J. Waterstone’s Exposition of a New Dynamico-Chemical
BAMMNCLLE e tw acche thy Wythe nad hie salt aieichcsote Reve Dolla toe e ere 170

Mr. J. Blackwall’s Examination of M. Virey’s Observations on
Aéronautic Spiders, published in the Bulletin des Sciences
ORS Te Ee a alo aati PR LIRE 180

Mr. H. J. Brooke on Mengite, a new Species of Mineral; on the
Characters of Aeschenite ; on Sarcolite, as distinct from Anal-
cime and Gmelinite; with other Mineralogical Notices..... 187

Mr. J. F. Daniell on a New Register-Pyrometer, for Measuring
the Expansions of Solids, and determining the higher De-
grees of Temperature upon the common Thermometric
Redle: (commnucd)'s, cia mae spies os <bidh.sjalify acon 191

CONTENTS. ¥v
Page
Rev. J. Challis on the Theory of the Compressibility of the
Matter composing the Nucleus of the Earth, as confirmed by
what is known of the Ellipticities of the Planets.......... 200
Mr. R. Phillips's Analysis of some Salts of Mercury ........ 205 ©
Mr. J. Prideaux’s Experiments on Vanadiate of Ammonia, and

on some other Compounds of Vanadium ..........+.-+-- 209
New Books:—Dr. Paris’s Life of Sir Humphry Davy (contznued) 214
Proceedings of the Royal Society......... ene PUM io} sSNA Se 223
——__________ Zoological Society ................06. 229
Mr. A. Connell’s Preparation of lodic Acid ............+..- 235
New RTIC HOOKS: <a. 4. sy tncssepteeresis She paihata nda s ital alos ia 236

Mr. Saull’s Geological Museum—Occultations of Planets and
fixed Stars by the Moon, in September 1831. Computed
for Greenwich, by T. Henderson, Esq. ; and circulated by
the Astronomical Society ..............-- SMe oe 237
Meteorological Observations........ omih atrial ecreriye = 238

NUMBER LVIII.—OCTOBER.

Mons, L, Elie de Beaumont’s Researches on some of the Revo-
lutions which have taken place on the Surface of the Globe;
presenting various Examples of the Coincidence between
the Elevation of Beds in certain Systems of Mountains, and
the sudden Changes which have produced the Lines of De-
marcation observable in certain Stages of the Sedimentary
PRES Motes Seale eset ete ncn NS CE cess 2 aie ais iereine (att 241

Mr. J. Blackwall on an undescribed Bird of the Family Falconide 264

Mr. H. J. Brooke on Monticellite, a new Species of Mineral; on
the Characters of Zoizite ; and on Cupreous Sulphate of Lead 265

Mr. J. F. Daniell on a New Register-Pyrometer, for Measuring
the Expansions of Solids, and determining the higher De-
grees of Temperature upon the common Thermometric

Cale (CONHNBER) Fae oso cs crc tepek no bie, ates CE Rick co sioiteee 268
Prof. Encke on the Calculation of the Orbits of Double Stars

ETE S TICE OE SCE REID BTR SSS See om 279
Mr. J. Nixon’s New Method of Levelling the Axis of a Transit

CON OM ares yo Merri crepe kp sulk 28, Se Minn 284
New Books :—Young’s Elementary Treatise on the Differential

MI Te ae Te cer ga ce rise a. chee eae 287
Procé@a@nsaw Of 10 FLOVAN SQOCIELY «a5 0. cc ene dense esas ees 293
———_———. Zoological Society .........-+....205. 302
M. Rouchas’s Red Colouring Matter produced by the Action

of Nitti npn AICONG!, ©... 6. ee «cs ue omai mae ae 313
Perchloric Acid—Red Solutions of Manganese— Powerful

Blectro- Mapai tay veces seen psec cena enis's s slaaAihine 314

Marking-

vi CONTENTS.

Page

Marking-Ink for Linen—Monthly American Journal of Geo-
logy and Natural Science ...... 1.2.2... sees ee ecco eee 315
Mr. Harvey's Researches on Naval Architecture .......... 316

Alterations and Errata in Mr. Waterston’s “ Exposition of a
New Dynamico-Chemical Principle ”—List of New Patents 317

Occultations of Planets and fixed Stars by the Moon, in
October 1831. Computed for Greenwich, by T. Hender-
son, Esq.; and circulated by the Astronomical Society—
Meteorological Observations ...........-e.ee ce eeerees 318

NUMBER LIX.—NOVEMBER.

Me Berzelis On « Vanaa ren is )ai5ei 2.2 ayede era oy: ofe vat her orehaie alps 321
Mr. J. Nixon’s Particulars of the Measurement, by various Me-
thods, of the Instrumental Error of the Horizon-Sector de-
scribed in Phil. Mag. vol. lix. (contznued)...........+000 337
Dr. £. Turner's: Notice:on Oxalte Acid wie v.05. o. sen haste 348
Mr. J. F. Daniell on a New Register-Pyrometer, for Measuring
the Expansions of Solids, and determining the higher De-
grees of Temperature upon the common Thermometric
oo | RTS OCLs es ls er Se oo Se 7 RC: 350
Mr, W. S. MacLeay’s Correction of a Quotation in a Paper
«« On the Impediments to the Study of Natural History,”
published in the Phil. Mag.and Annals for May 1831 .. .. 357
Mr. W. J. Henwood’s Notice of a Geological Survey of the
Mines of Cornwall; with a Programme of an intended Ar-
rangement of the leading Details of the Metalliferous Veins,
AE ne Aven Toke seperate Sei iee Pe * 358
Dr. W. Henry’s Experiments on the Disinfecting Powers of
increased Temperatures, with a view to the Suggestion of a

Substitute for Quarantine ce oc) te calle aja) cin «\ayelof get ee « 363
New Books :-—Rennie’s Edition of Montagu’s Ornithological
Dictionary: ( comlaneed ) oc. . iets ielaislpac tess as joasasniese eyes = pace

Dr. Paris’s Life of Sir Humphry Davy, Bart. (continued).... 379
Proceedings of the British Association for the Promotion of

PICIENGE Eo) cuave) ois lore oe. ayo: 6(Aincsueregace Pe role intelerou tel ierate VR cil
eee ee Zaplopicnl Society). -i.ctcte cua «sare wists 389
Dr. Thomson on theAtomic Weight of Barytes............ 392
M. Serullas on the Oxichlorates .............-.00 00000008 394

Occultations of Planets and fixed Stars by the Moon, in
November 1831. Computed for Greenwich, by T. Hen-
derson, Esq.; and circulated by the Astronomical Society—

Meteorological Observations.............+..ss0essecee 397
Calendar of the Meetings of the Scientific Bodies of London
FOL UGG mse fala ca eI STINE ahciete ati elS ©: sPipeld sico's so ontpbegaiekath 400

NUMBER

CONTENTS. Vii

NUMBER LX.—DECEMBER.
Page
Prof. Whewell on Isomorphism ; in Reply to Mr. Brooke.... 401
Unequal Refrangibility of Light on the undulatory Theory .. 412
Rev. R. Murphy on the Symmetrical Functions of a specified

Number of the Roots of an Equation ................ ee 413
Mr. A. H. Haworth’s Decas tridecoma Novarum Plantarum Suc-
(GTS, ERE, “03S REO Ore Seed rae 414
Mr. H. J. Brooke’s additional Remarks on Isomorphism...... 424
New Books :—Dr. Paris’s Life of Sir Humphry Davy ...... 426
Mr. Rennie’s Edition of Montagu’s Ornithological Dictionary
(continued). 2020. 2. PIAS PIR Pie Die th cts alinise: syd ato! 429
Proceedings of the Geological Society..............--.. 433
———__————— Linnean Society ...............+--..- 437
Astronomical Society ...........-..-- 442
——_—__———— Zoological Society .............-.-.. 447
PRA GTAR GS 2 25 3 ace, eerie eles rapes © aleista, olate's: aim spstmlet we 465
M. Serullas on the Preparation of Oxichlorate of Potash—
Separation of Antimony and Tin.................-+-+- 467
White’s Ephemeris — Mr. Johnstone on Vanadium — New
PAtCHtg ATi SUS vo dtet ds SAS Bp eiSbiecnocls ard - 468

Occultations of Planets and Fixed Stars by the Moon, in
December 1831. Computed for Greenwich, by T. Hender-
son, Esq.; and circulated by the Astronomical Society—
Meteorotopical Observations. 2. .5.0...cc0 sua oacieces «as 470

GENERAL ANALYTICAL InpExto the First Ten VoLuMEs
of the New SERIEs,

PLATES.

I. An Engraying illustrative of Mr. Srurcron’s Experiments on the
Thermo-Megnetism of Homogeneous Bodies.

If. A Plate illustrative of Mr. Danzett’s New Register-Pyrometer.

ERRATUM.

P. 32], last line, for present read next.

THE

PHILOSOPHICAL MAGAZINE

AND

ANNALS OF PHILOSOPHY.

———

[NEW SERIES. ]

JULY 1831.

I. On the Thermo-Magnetism of Homogeneous Bodies ; with
illustrative Experiments. By Mr. Wo. Sturceron, Lecturer
on Experimental Philosophy at the Hon. East India Company’ s
Military Academy, Adiscombe*.

[ With a Plate. ]

1. | ee or nine years have now elapsed since Dr. See-

beck, a Prussian philosopher, unfolded a most import-
ant secret of nature, by the discovery of magnetic powers in
various metallic combinations, by merely submitting their
points of union to different degrees of temperature ;—a dis-
covery of equal, if not superior interest, to that of electro-
magnetism by Cirsted the illustrious Dane. Each of those
discoveries marks a distinct and important epoch in the hi-
story of experimental science, and each philosopher now en-
joys that degree of fame to which he is so justly entitled.

2. Philosophers in every civilized country have repeated
the experiments of those celebrated men,—admired the beauty
and interest of the phenomena they present, and vied with
each other in adding new facts to those already known. Heat,
magnetism, and electricity are now blended in our experi-
ments, and new sciences have been reared upon the pheno-
mena they have jointly presented to our notice.

3. The discovery of C&rsted, and the train of curious and
interesting phenomena to which it has directed our view, rest,
principally, upon the action of metallic combinations, and a
mode of excitation, which to philosophers have long been

‘ known ;—whilst the discovery of Seebeck, on the contrary, not
only depends upon new arrangements, but also upon the novel

* Communicated by the Axthor.

N.S. Vol. 10. No. 55. July 1831. B mode

2 Mr. W. Sturgeon on the Thermo- Magnetism of

mode by which he calls forth the electric powers, and interro-
gates the magnetic phenomena they display.

4. In this mode of research, however, as well as in the
former, combinations of two, or more distinct metallic bodies
were still employed; and it appears that, by whatever inge-
nious contrivances other philosophers have pursued the in-
quiry, combinations of two, or more bodies have generally been
considered necessary for the display of thermo-magnetic phz-
nomena. I am not aware, however, that any experiments are
yet before the public illustrative of thermo-magnetic action
in one solitary piece of metal, or other homogeneous body.

5. In my “ Recent Experimental Researches in Galvanism,
Electro-Magnetism, &c.” a small work lately published, I
have stated that simple metallic bodies not only display dif-
ferent electric powers as regards each other, but also that
the various parts of each separate metal are relatively in dif-
ferent electric states at one and the same time, although in
close connection with each other by the best known conduct- .
ing material; that is, by the metal itself. And I have shown
by several experiments on homogeneous metals, that those
magnetic powers, which are regarded as inseparable from the
electric, can readily be brought into play either by the gal-
vanic or by the thermo process,—a circumstance, which to
me appeared highly confirmatory of the hypothesis.

6. Since writing that work, I have been induced to prose-
cute those inquiries to a still greater extent; and the experi-
ments and observations which are now about to be described,
appear to me to permit no further question as to the existence
of thermo-magnetic powers in most, if not in all, of the homoge-
neous metals; individually, and independently of any con-
nection with each other. And the phenomena they display,
are, in many cases, as decidedly obedient to certain unerring
laws, as in any thermo-magnetic arrangement whatever.

7. My first experiments for the detection of magnetism
by heat in single pieces of metal were not very successful ;
although the pieces were alloys, and consequently not homo-
geneous metals. I found however, after some trials, that by
hardening one end of a piece of steel, and keeping the other
end quite soft, the thermo-magnetic energies were always
called into play when any part near to the centre of the bar
was heated, and the extremities left at the ordinary tempera-
ture of the atmosphere.

8. Brass also, by the same treatment, displays thermo-
magnetic properties, which are easily detected by the galvano-
meter. It is a remarkable fact, however, that the electric cur-

rent in these metals proceeds in opposite directions as regards
the

Homogeneous Bodies; with illustrative Experiments. 3

the hard and soft ends. In cast steel the current in the bar
is from the hard to the soft part; but in brass.it flows in the
contrary direction. Fig. 1. (Pl. I.) is the shape of the steel or
brass bar, which I find very convenient in these experiments:
the extremities, which are a little bent, dip into the cups of
the galvanometer. There is no occasion, however, to employ
a galvanometer with brass; the bar, when heated at the bend,
may have its extremities brought into close contact, and one
side held over and parallel to the compass-needle; and the
nature of the deflection will indicate the direction of the elec-
tric current. When the bar is of steel, the direction of the
electric current will be indicated by the arrow: when brass
is employed, the current flows in the opposite direction.

9. I have magnetized the steel in all the various ways that
I could think of; but I have not found that its being a magnet
has any perceptible influence, either on the dzrection or the
power of the electric current excited within itself by heat.

First Class of Experiments with single pieces of Bismuth.

10. Bismuth is one of the metals wherein the magnetic
powers are finely developed by heat: the energies are
promptly displayed, even by small specimens cast into certain
forms; and, as their character can be examined without the
aid of a multiplying galvanometer, the phanomena are very
easily exhibited. Experiments on bismuth are therefore well
calculated to impress immediate conviction on the mind, as
to the distinguished and interesting character of the thermo-
magnetism of homogeneous bodies.

11. The first piece of bismuth which I employed in these
researches was cast into the shape of a rectangular frame, not
very unlikethe rim of an old-fashioned knee-buckle. Each side
of this frame was a rectangular prism, the faces of which were
each *3 of aninch broad. The sides, however, were not very
smooth, but no file was employed to level the inequalities. The
length of the frame outside measured 3°2 inches, the breadth
1:2 inch. he experiments were made by heating, at different
times, various parts of the frame in the apex of the flame of a
spirit-lamp: and, when any selected point was thus heated for
a few moments, one of the longest sides was immediately held
over, and parallel to a delicately suspended compass-needle ;
on which, the magnetism of the earth was pretty accurately
neutralized by means of a distant bar magnet: and the de-
flections of the needle were taken as an indication of the di-
rection in which the electric currents flowed round the me-
tallic frame.

12. The needle which I have employed is four inches long,
furnished with an agate cap, and suspended on a fine steel

point ;

4 Mr. W. Sturgeon on the Thermo-Magnetism of

point; it is also inclosed in a box with a glass cover. Care
was taken to neutralize the metallic frame between every two
experiments, by plunging it into cold water.

13. Fig. 2. will represent this frame of bismuth. It was
heated successively at the points a, 6, c, d, close to the angles ;
but those angles were kept out of the flame of the spirit-lamp.
These points were selected for the points of heat, from a no-
tion which I had previously entertained, that heat might pos-
sibly be obstructed by turning sharp angles, and thereby in-
fluence the direction of the electric currents to which it gave
birth.

a, the current flowed from 6 to a

When the point J b, .sscssscccceseseessenessees 5 to a
of heat. Was ak]) Gy. ss. vadcdecstdecceveeeawadsl Oto la
Gh uei vescthcadécackabbarersee MP EONOL

To prevent confusion, the side a 6, only, is chosen to show
the directions of the electric currents. It is to be understood,
however, that those currents were,continuous round the rect-
angular frame.

14, When the experiments were repeated, the direction of
the current changed when the point of heat was at 5; at all
the other points the currents proceeded as at first. By vary-
ing the situation of the point of heat several times near to 6,
it was found that, when applied anywhere within half an inch
of the angle, the current was from 6 to a as at first; but when
the point of heat was one inch distant from the angle 6, the
current invariably proceeded from ato. From these re-
sults it was evident, that between half an inch and one inch
from the angle, there was a point which, if heated, no electric
current would be excited. By various trials this neutral point
was found to be situated at a little more than half an inch
from the angle 6. So that in general, if all the first half-inch
were heated, the current would proceed from 6 to a; but if
the more distant half-inch from the angle was heated, the
current flowed in the opposite direction. Again, as this last
current was also in the opposite direction to that excited by
heating the point a, there would evidently be another neutral
point still nearer toa. This point was determined at nearly
half way between the angles a and 6, but a little nearer to
the former than to the latter.

15. In this way the situation of the point of heat was varied
in the side cd. One neutral point only on this side was de-
tected, which was nearly half-way between the angles c and d.
If any point in, or the whole of the half nearest to, c were
heated, the current proceeded from d toc; but if heat was
applied to the other half nearest to d, or to any particular
point in that half, the current flowed from c to d. és

16. by

Homogeneous Bodies ; with illustrative Experiments. 5

16. By consulting the direction of the arrows in fig. 2. the
reader will easily ascertain the direction of the electric cur-
rents when any particular part of the apparatus is heated; for
by heating any point within the range of any individual arrow,
that arrow will point out the direction of the electric current.
Or, if the whole length of that arrow be heated at the same
time, the current still flows in the same direction, and is con-
tinued in every part of the frame. The same explanation
will also apply to all the other figures, unless otherwise ex-
pressed.

Second Class of Experiments.

17. These experiments were also made with a rectangular
frame of bismuth exactly of the same length as the former,
and about 1°75 inch broad. More care was taken in the
casting, and the frame was a better figure.

18. The direction of the arrows in fig. 3. will point out the
course of the electric current when any point opposite to them
is heated. It will be observed by consulting that figure, that
every angle is a neutral point; and that the long sides have
each one neutral point, and when this is heated, no current is
excited.

19. ‘There is a circumstance connected with these experi-
ments which is well worthy of remark. On the side ab of
the rectangle, and near to b, there was a protuberance on the
inner face: when the point of heat was between this pro-
tuberance and the angle J, no current was excited; but on
the other side of the protuberance being the point of heat, a
powerful electric current was put into motion; so that, strictly
speaking, the arrow ought not to reach to the angle . The
protuberance was afterwards filed down, and that part levelled
with the rest of the side: no difference was produced in the
thermo-magnetic character of that part of the frame by the
change thus made. Hence it would appear, that, the internal
structure of the metal alone, operates in giving direction to
electric currents excited by heat. This opinion will appear
much better supported by experiments and observations,
which will be spoken of in the sequel.

20. I must notice in this place, that the thermo-magnetic
energies in this rectangle vary considerably by heating dif-
ferent points. When the point of heat is in the side a 0, the
current which sets in from 6 to a is much more powerful than
the opposite current from a to 6; so that by heating any part
in the half nearest to a, a stronger current is excited than by
heating a point similarly situated with regard to d.

21. When either of those halves is uniformly heated, a

needate

6 Mr. W. Sturgeon on the Thermo-Magnetism of

needle is more deflected than if the heat were confined to a
single point. When the whole side ad is uniformly heated, in
consequence of the superior energies attributable to the half
nearest to a, the current is directed from b to a; but the
energies of this resulting force are necessarily very feeble.

Third Class of Experiments.

22. Three rectangular frames of bismuth, which I shall
distinguish by the letters A, B, C, were cast in the same mould,
and from the same mass of metal. The longest side of each
frame measured 4°5 inches, and the shorter sides 2 inches.
The weight of the whole was 21 ounces; so that the average
weight of each was 7 ounces. ‘They were cast under different
circumstances, as regards the temperature of the mould, agita-
tion, position, &c.

23. The rectangle A was cast whilst the mould was quite
cold; its plane horizontal, and its longest sides parallel to
the magnetic meridian. The metal was all poured into the
mould (which was simply a groove in one of the flat sides
of a Bath brick) at one particular point, which was in one of
the longest sides of the rectangle, and about 1:5 inch from one
of the angles. The metal consequently flowed from this point
to every other part of the mould. ‘T'wo' powerful bar mag-
nets were applied to the two longest sides whilst the bismuth
remained in a fluid state; they were drawn from the centre,
of each long side of the rectangle in precisely the same man-
ner as is practised in magnetizing a needle by the double
touch. The process was continued till some time after the
metal was set. The mould was kept perfectly at rest all the
time.

24. The rectangle B was cast whilst the mould was quite
warm from the heat communicated to it by the last casting.
The magnetizing process was carried on as before, but the
metal was agitated as much as possible all the time. The
position of the mould was the same as whilst casting the rect-
angle A. The magnets in both cases were so applied, that
if the magnetism of the earth had any influence in arranging
the particles of the fluid metal*, those artificial magnets would
have tended to promote that arrangement.

25. The rectangle C was cast whilst the mould was quite
hot, and with its longest sides at right angles to the magnetic
meridian. No magnet was applied to the bismuth, but con-
tinued agitation was kept up till long after the metal was set.

™ From some previous observations, I had formed an idea that this
might possibly be the case.

26. Experi-

Homogeneous Bodies ; with illustrative Experiments. 7

26. Experiments with the rectangle A.—The arrows in fig. 4.
will, in general, indicate the direction of the electric currents
in this piece of bismuth. There are, however, circumstances
connected with the experiments which require some further
explanation.—I shall endeavour to point out these particulars
with some degree of minuteness, commencing with those which
were observed when the point of heat was on the side ab;
and proceed successively with the other sides according to the
regular order of the letters.

Side ab. Current.
Close tore sce ceeece NOME sess secr. 7
Point of | °® sang hadts a «.. very feeble ee PES aisha
let < centre of a6........ more powerfu

| one inch from 6 ... very powerful
Lclose to b............ very powerful from d to a.
Neutral point °5 inch from 8.

Side be.
: close to .....eeee6e Powerful ......
pe a {centr of bc......... powerful vo Lfrom ee
re Close to C.....+00ee.. powerful ...... from c to d.
Neutral point *25 from c.

Side ed.
(close to c............ powerful ......
| one inch from c ... feeble .........
< centre of cd......... powerful ...... f aie
| one inch from d ... more air eet eee
(close. to d............ powerful ...... from d toc.

Neutral points °75 inch from d, and 1°5 inch from c. The
latter was the gate or point at which the metal entered the
mould.

Side da.—To whatever part of this side of the rectangle
heat was applied, the electric current flowed from a to d; but
the energies were more powerful when the point of heat was
close to d, than when in any other part of the side d a.

27. It will be observed that in this rectangle there are only
two of the angles, a and d, which are neutral points. The
other angles, c and d, when heated produce very powerful
electric currents; indeed, much more so than when the point
of heat is in any other part of the metallic frame. When those
two angles are heated at the same time, their energies being
excited in the same direction, conspire to produce effect on the
needle, which becomes much more deflected than when one
angle only is heated, Precisely the same thing happens when
any other two or more points are simultaneously heated, the

energies

from d to c.
Point of
heat

8 Mr. W. Sturgeon on the Thermo-Magnetism of

energies of which are directed in one and the same way round
the rectangle.

28. In the side cd there are two neutral points; one of
which is exactly at the gate, or that point at which the metal
was poured into the mould. I mention this circumstance more
particularly, because I have observed that, when the point of
heat is situated on different sides of the gate in any of these
frames of bismuth, there are generally opposite currents eli-
cited ; or, in other words, the gate is generally a neutral point.
The letter o in figs. 4. 5. and 6. denotes the gate in each.

29. Experiments with the rectangle B.—By consulting fig. 5,
it will be observed that the greater part of the side ad is neu-
tral. No deflection of the needle could be produced when the
point exceeded one inch from either of the angles a or 8,

30. The side cd has three neutral points, one of which is
at the point o, where the metal entered the mould. The two
short sides, 6c and da, have each one neutral point. In ad
it is at equal distances from the angles a and d. In dec the
neutral point is nearer to ¢ than to 0.

31. The opposite angles a and c are decidedly neutral
points; but when the angles d or c were heated, very power-
ful currents were excited. The arrows on each side of the
angle & are both directed the same way, and consequently
would represent that angle of one uniform character ; but it
was found by repeated trials, that there are two neutral points
very close to the angle 4, but on different sides; and so close
to each other, that it required a very fine-pointed flame to
heat one of those points without heating the other also.

32. Experiments with the rectangle C.— There are three
neutral points in each of the long sides of this rectangle; one
of which is at 0, the point where the metal entered the mould.
In each of the short sides there is one neutral point, situated
nearly at their centres, as is shown by fig. 6.

33. The angles c and d are perfectly inactive when uni-
formly heated; but the angles a and 8, although represented
by the arrows as causing conspiring currents on both sides of
each angle, have, in fact, each of them two neutral points very
close to each other; so that the needle will be deflected vari-
ously by heating different adjoining points about either of
those angles.

34. When those parts of the rectangle which are opposite
to the arrows 77 are simultaneously heated, the energies of
the conspiring currents become very powerful indeed; and
the needle may be driven round on its pivot through a whole
circle by following it up with the side of the rectangle. The

electric currents excited in this rectangle are more powerful
than

Homogeneous Bodies; with illustrative Experiments. 9

than in either of the two former; particularly when heated
opposite to the arrows iz. The thermo-magnetic powers of
A and B, however, when those rectangles were heated at two
or more conspiring active points, would frequently deflect the
needle over an arc of 30° or 40° by the first impulse.

35. The rectangle A was so exceedingly sensible by the
slightest inequalities of temperature in its various parts, that
the heat imparted by the finger and thumb by which it was
held, would excite an electric current of sufficient energy
to deflect the needle 4° or 5°. Indeed, the temperature of
the metal was very seldom so far equalized as to render its
electric powers completely inert. The natural changes in the
temperature of the atmosphere seem to be almost sufficient
to perpetuate electric currents, without any artificial change
whatever.

Fourth Class of Experiments.

36. As it had appeared from the preceding experiments,
that considerable thermo-magnetic action was elicited by bis-
muth when cast into the shape of rectangular frames, I was
desirous to ascertain if those powers were communicated to it
by employing it in that particular shape; or if it would still
display thermo-magnetic phenomena when cast into other
forms. ‘To set this question at rest, I cast several circular
rings, or frames of bismuth. The exterior diameter of each
ring was 4 inches, and the interior diameter 3°5, leaving the
metal °25 inch thick. They were cast with the plane of the
mould horizontal, and open at the upper surface. The height
of each ring when in that position was about *4 inch.

37. By applying the flame of a spirit-lamp to various parts
of each ring, and immediately presenting the metal to the
compass-needle in precisely the same way as had been done
with the rectangles (11.), several active points in each ring
were soon discovered, the energies of which were continuous
throughout every part of the circular frame, putting the whole
circle into a state of thermo-magnetic activity. Several in-
active or neutral points were also found in these rings, by
heating which, no perceptible influence was exercised on the
needle by bringing the metal close to it. These results left no
question remaining as to the magnetic power being innate and
natural to the metal; and not communicated to it by its assu-
ming any particular form. It must certainly be acknowledged,
however, that the rings have never displayed the thermo-
magnetic enemy in so exalted a degree as I have observed
in the rectangles; but this difference of energy may possibly
be attributable to the difference in the extent of surface which

N.S. Vol. 10. No. 55, July 1831, C can

10 Mr. W. Sturgeon on the Thermo-magnetism of

can be exposed to the needle by having the bismuth in those
varieties of shapes; for when the metal is in the shape of a
circular ring, it is impossible to bring any more than a very
small portion of its surface at any one time sufficiently near
to the needle to examine the character of the magnetism
which it displays. With rectangles, or other straight-sided
frames, it is quite otherwise; for with those, the metal may not
only be brought parallel and close to the needle for a consi-
derable extent, but, if the frame be sufficiently long, it can be
made to operate on both poles of the needle at the same time,
—an advantage of considerable importance in experiments of
this delicate character*.

38. Fig. 7. will illustrate the thermo-magnetic character of
one of these rings, and will be sufficient, also, to give a toler-
ably good idea of the thermo-magnetism displayed by similar
rings of bismuth generally: although some trifling difference
as to the energy, number, and situation of the active points will
frequently be found amongst them; for, in the present state
of the inquiry, it is next to impossible to procure two exactly
alike; nor is it easy to predict an active or an inactive point
in a ring of bismuth which is symmetrical in all its parts.

39. It will be observed, by contemplating fig. 7, that the
gate o is a neutral point. This I have also shown (28) is the
case in rectangles; and, indeed, I believe that the gate will al-
ways be found in that state, into whatever form of open frames
bismuth may be cast.

40. For the convenience of bringing a greater part of the

* Should it be asked why the multiplying galvanometer was not resorted
to in these delicate experiments, the answer would be, that that instrument,
however valuable it may be for some purposes, is quite inapplicable in
these inquiries; where every metal, excepting that under examination,
should studiously be avoided, and on no account be permitted to enter
the thermo-magnetic circuit. Errors frequently occur by employing the
multiplier whilst examining the thermo-magnetic character of very small
specimens of metals. Besides, the circuit in that instrument is frequently
much too long to be penetrated by the feeble energies which are sometimes
displayed in homogeneous bodies, but which are easily detected in short
circuits, through which they will pass with very great freedom. Doubts, also,
regarding the correctness of the results, would necessarily have presented
themselves, had any other metal been permitted to enter the circuit ; and
with very great propriety indeed, might every experiment have been ques-
tioned, had the galvanometer, with its copper multiplying wire, mercurial
cups, &c. been employed in an inquiry which professes for its object the
contemplation of the thermo-magnetism of homogeneous bodies alone.
Moreover, these researches, as will presently be shown, have led to dis-
coveries which could never have been made by the employment of the
multiplying galyanometer ; and the character of several of the experiments
is such, as entirely to preclude the use of that instrument in their exhibi-
tion.

edges

Homogeneous Bodies ; with illustrative Experiments. 11

edges of curvilinear frames as close as possible to the mag-
netic needle, I cast several into an elliptical form; the diameters
of each of which were nearly as to 3 to 1. Every one of these
frames became magnetic by heating at various points, in the
manner already described ; and the thermo-magnetic energies
were as promptly displayed in every part of the curve by heat-
ing an individual point, as in any thermo-magnetic circuit
whatever.

41. I must not omit to mention a very extraordinary cir-
cumstance which occurred whilst varying the experiments
with one of those elliptical frames; because the same cause
frequently produces very singular changes in the thermo-
magnetic character of curvilinear and other frames of bis-
muth.

42. Having proceeded in the usual way (11), I succeeded
in detecting several active points in the ellipse. The direc-
tions of the various currents which were excited by heating
those points are indicated by the arrows in fig. 8; the
arrow always pointing in the direction of the current when
any point was heated within its length. This done, I made a
deep curved notch in the inner side of the rim at the point d,
fig. 9, by means of the convex side of a half-round file. ‘This
small alteration in the edge of the frame caused such a won-
derful difference in the activity of its thermo-magnetism as to
surpass anything I had hitherto observed. The magnetic
energies not only became very much exalted, but in several
parts of the frame had completely changed their direction.
When heated at the points 0, orf, the deflection of the needle
was at least three times greater than before the notch was
made. When those two points were heated at the same time,
the conspiring magnetic energies thus excited, deflected the
needle 50° at the first impulse; and by changing the direction
of the frame to promote the deflections, the needle was soon
made to sweep an arc of more than 200°; and by following
the oscillating needle with the edge of the frame, the former
was driven, by the thermo-magnetic forces of the latter, several
times quite round the whole circle*.

Remarks

* My motive for making this deep notch in the side of the frame, was
that of checking the progress of the heat in one direction more than
another, when applied to either side of it,—an object which I had in view
from the commencement of these experiments, and which I had in vain
attempted to accomplish by means of angular points (13); and from fre-
quent disappointments by the apparently fortuitous results in the preced-
ing, and many other experiments which I have not mentioned, I had lost
all hope of arriving at anything like interposition, in any other way than
that of modifying the crystallization of the metal. The results of this ex-
periment, however, were very singular; and I have since found, that

C2 similar

12 Mr. W. Sturgeon on the Thermo-magnetism of

Remarks on the preceding Experiments.

43. It would be needless (indeed almost endless) to de-
scribe all the peculiarities which have attended the numerous
repetitions of the preceding experiments; and the variety of
circumstances under which I have cast rectangular, triangular,
and curvilinear frames of bismuth; as the phenomena already
described, with a few summary remarks, will ‘pourtray their
general character.

I am not certain that any peculiar property is communi-
cated to bismuth by the magnetic process (23), or by the
position of the metal as regards the cardinal points, whilst
casting. I have frequently cast rectangles under these cir-
cumstances, but have not found more regularity in the display
of their thermo-magnetism than in those which were cast
under circumstances quite different.

In general, small, and well-formed rectangles (17) (fig. 3-)
operate with much greater regularity, as regards the angles,
than those which are of larger dimensions (figs. 4, 5, 6). But
it frequently happens that the energies of the latter are much
superior to those of the former.

The currents, more frequently than otherwise, proceed in
opposite directions, when excited on different sides of an
angle. And in those cases where it happens otherwise, the
neutral point is situated almost close to the angle.

The gate is invariably a neutral point when the mould is
not very hot at the time of casting, and more frequently than
otherwise in castings generally.

The thermo-magnetic character of frames of bismuth,
whether angular or curvilinear, may be considerably modified
by removing, or partially removing, crystalline groups, or by
altering their forms. (41, 42 and note.)

Every part of a continuous ring or rectangular frame of

similar results frequently happen from the same cause : this however is not
always the case; it takes place most frequently in those frames which,
whilst whole, are not very active; and a neutral point ought to be se-
lected for the situation of the notch. I have frequently reduced parti-
cular parts of circular rims of bismuth with a hot iron, and sometimes
with the flame of a spirit-lamp, instead of a file, and with similar results,
There is another method of exhibiting a very remarkable and nearly
allied property of thermo-magnetism, much more decidedly than by that
of filing,—by experiments which do not properly belong to this class,
although they were suggested by the results of the experiment last de-
scribed ; besides, there are impediments of which I must warn the reader,
before I can possibly describe the method of arriving at anything like suc-
cess. The circumstances, however, which I have called impediments,
emanate from the display of a very interesting class of phanomena, which
J shall presently describe.
bismuth

Homogeneous Bodies ; with illustrative Experiments. 1%

bismuth becomes magnetic by heating the smallest possible
point.

The phaenomena generally, are sufficiently striking to be
exhibited in a lecture-room, and to be observed by the most
distant auditor, provided the needle be neutralized. Two,
or more rectangular frames may be selected, and properly
adjusted side by side, so that their combined energies may be
made to operate simultaneously on a very large needle. In
this way the experiments may be made on a very extensive
scale.

Fifth Class of Experiments.

44, The experiments which I am now about to introduce
present phenomena, perhaps somewhat less complicated,
though by no means less curious, than those I have already
described.

I had observed, whilst experimenting with a rectangular
frame of bismuth of large dimensions, that the needle would
sometimes be deflected in one direction and sometimes in the
other, even when the point of heat was not varied. Struck
by this unusual phenomenon, I proceeded to examine it with
some degree of minuteness, and with an intention of ascer-
taining its cause.

45. Before noticing this apparent anomaly, I had con-
stantly held the plane of each rectangle in the plane of the
magnetic meridian, and with its lower edge as close as possi-
ble to the needle,—a position, which I considered as the most
likely to obtain true results, because, when so placed, the
upper edge of the frame, in consequence of its great distance,
could not affect the deflections of the needle produced by the
thermo-magnetic forces in the lower side. This position of
the frame would certainly have been better than any other for
ascertaining the direction of single electric currents, or those
thermo-magnetic forces which are circumfused in the appa-
ratus of Seebeck, and other similar combinations; although
a slight degree of inclination either to the east or west, with
such compound apparatus, would not very materially have af-
fected the results. I soon became convinced, however, that
the anomaly which I had noticed proceeded entirely from
that cause; for if the plane of the rectangle inclined to the
east, the needle would be deflected in a contrary direction to
that which it assumed, by inclining the plane of the rectangle
to the west. By several trials it was found, that when the
plane of the frame became nearly horizontal eastward (still
keeping the end north), a greater deflection was obtained than
by holding it at any other angle on that side of the meridian.
And by placing it in a similar position to the west of the me-

ridian,

It Mr. W. Sturgeon on the Thermo-magnetism of

ridian, the greatest deflection was again produced in the op-
posite direction to the former.

46. Considering this as one step at least towards the dis-
covery of the cause of this novel phenomenon, I proceeded
to examine the opposite side of the frame, which I supposed
might possibly present similar effects. or this purpose I
heated one of the points in that side which by previous trials
was found to be very active, and then placed it directly over
the magnetic needle, keeping the plane of the frame in the
magnetic meridian, and the same end north as had been in
that position whilst experimenting with the other side. ‘The
needle was deflected in precisely the same direction as I had
always found it to be by a similar position of the frame, and
with the same point of heat. I afterwards inclined the plane
of the frame sometimes eastward, at others to the west; but
in no instance could I obtain the least indication of results
similar to those which I had noticed whilst the opposite side
of the frame was nearest to the needle. Thinking that the
different active points might possibly operate under different
laws, I next heated the point which had before presented
the extraordinary phznomenon, still keeping the other side
nearest to the needle; but nothing remarkable was noticed by
this variation of the experiment. The needle continued to be
deflected in one uniform direction, whatever inclination was
given to the plane of the rectangle. I tried the other sides of
the rectangle in precisely the same way, but obtained no un-
usual results. It now appeared evident that one side of the
frame was endued with peculiar properties which the other
sides could not be made to exhibit, which soon proved to be
the fact.

47. When this side was heated at one particular point, two
distinct electric currents were called forth; one of which may
be distinguished by the name of general current, because it
pervaded every part of the metallic frame; the other cur-
rent was perfectly local, and could be traced only to a short
distance from the point of heat. It never reached further
than the angle, and returned into itself on the opposite face
of the solid prism which formed that side of the frame.

48. From this singular result, it appeared likely that some
inaccuracy might possibly have occurred in the conclusions
I had already drawn from the former experiments. Fortu-
nately the rectangles were not broken, and I had an oppor-
tunity of examining them again: but it seems that they were
of too small dimensions to produce local currents, as I found
them to operate exactly as at first. On trying one of the
circular rings, however, another curious fact was discovered,

which

Homogeneous Bodies ; with illustrative Experiments. 15

which at that time was not a little surprising. A reference to
fig. 10. will assist the illustration of this singular property
discovered in the ring of bismuth.

49. When the outside of the ring at 6 was held for a few
moments in the point of a well-defined flame of a spirit-lamp,
the electric current in every part of the ring was in the direc-
tion of the exterior arrow; but when the inner side of the
rim opposite to} was similarly heated, the current proceeded
in the contrary direction, as indicated by the interior arrow.
And so directly opposite and close to each other were these
two active points, that a transverse section of the metal at the
point 4, would have embraced them both. I have since that
time observed active points similarly situated in other pieces
of bismuth.

50. Experiments with a solid Prism of Bismuth.—That side
of the rectangle (47) which had exhibited /ocal electric cur-
rents was now cut from the frame, for the purpose of ascer-
taining whether phenomena similar to those described (47)
would be exhibited by this prism when examined as a distinct
individual mass. Fig. 11. will represent this prism or bar of
bismuth: when heated at 0, the former active point, the bar be-
came highly magnetic, displaying those energies in a very ex-
alted degree. The electric current was traced from the point of
heat towards the end c, along that side of the prism which in
the figure is hid from view. It proceeded across the end c, as
shown by the curved arrow; and returned to the heated point
along the front face of the prism: so that when heated, if the
front face a, b, c were placed over and parallel to the needle,
and the end ¢ north, the north end of the needle would be
deflected towards the east; and by simply turning the prism the
other side up, the needle would be deflected towards the west.
By thus turning the bar, at suitable times to promote the de-
flections, the needle could be made to sweep an arc of 90°.

51. The other two faces of the prism were nearly neutral,
och of them partaking of the opposing currents in the active
sides.

52. The bar was afterwards heated at various parts of its
surface, and the direction and energy of the currents ascer-
tained by the deflections of the compass-needle. It was ulti-
mately found that when the whole of the end ¢ was uniformly
heated, the most powerful current was excited; its course was
still in the same faces of the prism, but its direction was reversed.

53. When the end a was uniformly heated, no thermo-
magnetism was elicited, until, as the heat advanced in the bar,
the temperature became disturbed at the point 6. ‘This ac-
complished, those powers were again roused from their qui-

escence,

16 Mr. W. Sturgeon on the Thermo-magnetism of

escence, and displayed phenomena precisely of the same cha-
racter as when the bar was heated at the point 6 only.

54. The neutral end a was now cut off at the point b; and
the remaining bar displayed thermo-magnetism to whatever
end heat was applied. The currents still passed over the same
faces, and, as regards the point of heat, uniformly set out over
the same face and returned by the other. Hence the apparent
contrariety in its direction when the bar was heated at dif-
ferent ends. These results led to further experiments with
bars, and other forms of solid homogeneous metallic masses ;
some of which have developed very curious phenomena, which
appear to observe an uniformity in the laws of their exhibi-
tion.

55. Experiments with a cylindrical Bar of Antimony.—This
bar was 8 inches long and ‘75 inch diameter. It was very
far from having an uniform surface, being much more ca-
vernous on one side than the other, from air-bubbles whilst
casting. It was heated at various points of its surface by a
very fine-pointed flame of a spirit-lamp; and its magnetism
thus excited was traced by its action on the compass-needle.
It was ultimately discovered, that whatever point near to the
extremities of the cylinder was selected for the point of heat,
the electric current invariably flowed over the same parts of
its surface; and when either of the ends was uniformly heated,
whilst the other was kept at the temperature of the atmo-
sphere, the bar became highly magnetic; exhibiting phzeno-
mena similar to those already spoken of as appertaining to
the prism of bismuth (54). The electric current constantly
passed over the dense and opposite cavernous sides, whilst
the intermediate longitudinal lines were nearly neutral.

56. Fig. 12 will give a good idea of the direction of the
electric currents excited in this bar of antimony when one of
its ends was uniformly heated. The cylinder is supposed to
be divided into halves in the plane of its axis, and termi-
nating on each side by the dense and cavernous parts of its
surface. The two halves are placed edge to edge, with their
convex sides upwards. The dotted line in each half will re-
present the neutral line, or that longitudinal line on each side
of the bar, which when placed parallel over the needle, no
deflection was produced. The active lines are cd, and a),
ab: the two latter correspond to each other when the halves
of the cylinder are replaced or brought together. It is to be
observed, however, that the thermo-magnetic energies of the
cylinder were not confined to two longitudinal lines; for every
part of the surface near to the heated end was more or less
magnetic; but in consequence of the recuryed ss .

which

Homogeneous Bodies ; with illustrative Experiments. 17

which the electric currents flowed over the surface, there were
necessarily two longitudinal lines more active than any other
part. These lines passed through the dense and opposite
cavernous sides, and may be termed the lines of greatest
energy. The neutral lines were also a consequence of the
recurved flow of the electric currents by intersecting them at
right angles; and as those intersections were in a series of
points nearly parallel to the axis, those neutral lines were
nearly parallel to the axis also.

57. When the other end of the cylindrical bar was heated,
the lines of greatest energy were still on the same parts of the
surface, but the electric currents flowed in an opposite direc-
tion to the former; so that to whatever end of the bar heat
was applied, the current uniformly proceeded from the heated
end along the dense side cd, and returned over the opposite
or cavernous part of the surface ab, a b.

58. The thermo-magnetic energies never reached to the
cold end of the bar, but returned to the point of heat in di-
rections indicated by the arrows, and at no great distance
from the heated end. The same laws hold good in all cylin-
drical bars of antimony of small dimensions, which are not
of an uniform density on every side of the axis. I have
broken several into fragments for the purpose of examining
their internal structure, and have always observed, that when
they have displayed phenomena similar to those last de-
scribed, their density is not uniform; and the side of the cy-
linder, which in a transverse fracture will exhibit the most
compact texture, may generally be predicted by an observance
of the thermo-magnetic phanomena which it will display
whilst whole.

59. Cylindrical bars of antimony of an uniform density on
every side of the axis, and more than two inches diameter,
diaplay thermo-magnetic pheenomena with very great preci-
sion, and a rigid observance of certain laws.

60. When a bar of this description, and 6 or 8 inches
long, has been cast in a vertical mould of sand, let its ends be
struck off with a sharp-edged hammer, making the sections
transverse and not ragged. Apply the flame of a fierce spirit-
lamp for a few moments to the convex surface close to one
end of the cylinder, and immediately place the heated side
downwards, over and parallel to a delicately suspended com-
pass-needle. If the heated end of the bar be placed north,
the north end of the needle will be deflected eastward, show-
ing that the electric current by which it is deflected is flowing
along the lower side of the bar, from the point of heat towards
the cold end.

N.S. Vol. 10. No. 55. July 1831. 1 61. Let

18 Mr. W. Sturgeon on the Thermo-magnetism of

61. Let the same point be again heated in a similar manner,
and again place the cylinder over the needle with its heated
end north, but with the point of heat upwards. The north
end of the needle in this case will be deflected towards the
west, or in the opposite direction to that which it assumed in
the former experiment. This deflection of the needle indicates
the electric current to be flowing in the cold side of the cylin-
der from south to north, or in the opposite direction to that
in which it flows in the heated side.

62. Heat the same point again: but instead of placing the
heated or opposite side of the cylinder over the needle, as in
the former cases, place one of those parts of the surface over
it, which is about 90° from the point of ‘heat, still keeping the
cylinder parallel to the needle. In this position the latter is
scarcely affected; and by a few trials a line will be found on
the surface of the cylinder, and nearly parallel to its axis,
which has no action whatever on the needle. ‘This is one of
the neutral lines; and by a few trials on the other side of the
point of heat, another newfral line will be discovered. ‘These
lines are generally at about 90° from a line drawn from the
point of heat to the other end of the bar, and parallel to the
axis.

63. This latter line is one of the lines of greatest energy ;
the corresponding line of greatest energy being parallel, but
on the opposite side of the cylinder (56).

64. Similar phenomena will be displayed by making any
other part of the convex surface near to the ends of the cylin-
der the point of heat. The current uniformly flows over the
surface on the heated side from the point of heat, expands
into two distinct tides which sweep the surface of the metal,
and reuniting on the opposite side recurves into itself at the
heated point of the cylinder.

65. The general distribution of the electric force on the
surface of the cylinder by heating it as directed (60, 61, 62),
will be pretty accurately indicated by the arrows in fig. 13.
The cylinder is supposed to be divided into halves, and
its convex sides upwards, as in fig. 12 (56). The straight
arrows indicate the lines of greatest energy; and the edges
ab, ab, which coincide when the halves are replaced, are in
one of the neutral lines: the other neutral line is cd in the
centre of the figure.

66. The thermo-magnetic energies can hardly ever be
traced more than four inches from the point of heat: they are,
however, excited to a certain extent by the slightest disturb-
ance of temperature near to either of the ends of the cylin-

der.
67. When

Homogeneous Bodies ; with illustrative Experiments. 19

67. When any point is suddenly made pretty hot, without
elevating the temperature of the opposite side, which can easily
be done when a cylinder is employed of more than two inches
diameter, the electric force is very considerable, and will de-
flect the needle to an angle of 20° or 30°; and by dexterously
turning it the other side up before the returning needle ar-
rives at the magnetic meridian, another impulse is given, and
the angle increased on the other side. ‘Two or three turns of
the cylinder in this way will cause the needle to sweep a con-
siderable arc; but the arc over which the needle passes will
be very much increased if the needle be followed up by the
active sides of the cylinder, still keeping the one parallel to
the other. :

Remarks on the preceding Experiment.

68. There is a peculiarity in the phenomena displayed in
this experiment which has not been observed in any of the
rest:— When acylinder of antimony is cavernous on one side,
I have shown (57) that the electric current invariably flows
over the same parts of the surface; but in cylinders of uniform
density on every side of the axis, the law of thermo-magnetic
action is very different, and the route of the electric current
over the surface of the metal entirely depends upon the situa-
tion of the point of heat.

69. When a cylindrical bar of antimony is uniformly dense
on every side of its axis, it will invariably present a regular
crystalline form at every transverse fracture. The general
contour of the section is that of a series of exceedingly thin,
concentric crystalline laminz, of which the whole face of the
fracture seems to be composed from the centre to the surface
of the cylinder. Aided by a magnifier, the eye is enabled to
trace apparent radiating veins, which by close inspection are
observed to separate the laminz into distinct parcels or tall
narrow bundles, with their edges inclined to each other at
various angles, both salient and re-entering: and the apparent
veins, which are frequently nothing more than an angle at
which two bundles of laminz unite, give to the fracture a
beautiful glittering appearance. Some of those radiant veins,
however, are absolutely the flat facets of laminze, or more fre-
quently the sloping edges of bundles of them, which have a
brilliancy far superior to any other part of the fracture. The
general position of the laminz, however, is, that their flat sur-
faces are presented to the axis of the cylinder: and although
there are certainly objections to this position being uniformly
determined by the erystalline lamina, because of several of
the piles or bundles being posited at various angles, yet the

Le major

20 Mr. W. Sturgeon on the Thermo-magnetism of

major part of those piles are absolutely set in that position,
and not a single crystalline film has its plane determined at
right angles to the axis of the metal. Hence it is that the
edges of the greatest part of the bundles of laminz are pre-
sented to view at every transverse fracture, and may be com-
pared to tall narrow bundles of thin metallic leaves, or slips
of paper, placed round a central nucleus, with one of their
narrow ends presented to the centre and the other towards the
surface of the cylinder; which position, together with others
which some of those bundles assume, give to them the ap-
pearance of radii, with various degrees of splendour. Fig. 14.
will assist in giving an idea of the general disposition of the
strata of crystals in a transverse section of an uniformly dense
cylinder of antimony.

70. If the sharp edge of a hammer be applied in the direc- .
tion of the axis, the cylinder may be completely dissected
from its surface to its centre; or the crystalline layers may
be peeled off one after another with very great accuracy, as
far as the dissection is required to be carried on. Whena
cylinder of antimony is thus disrobed, it presents an exceed-
ingly beautiful appearance: the refulgent facets of its crystals
are exposed to view, which stud its surface as if it were
decked in a most brilliant coat of mail; whilst the multitude
of spangles which those facets display are now seen to be dis-
posed in the crystalline arrangement already described.

71. Assuming, then, that the general crystalline arrange-
ment is that of concentric laminz, two hypotheses may per-
haps present themselves for an explanation of the thermo-
magnetic phenomena elicited in an uniform cylindrical bar
of antimony, one of which, it appears to me, will ultimately
be found to be the true theory.

72. First, then, it may be supposed that the opposite faces
of each metallic film are in different states of electricity, or at
least that they have different thermo-magnetic qualities. If
it could be satisfactorily proved that this were the case, their
concentric arrangement would reconcile the phanomena to
all those which are displayed by the juxta-position of any
pair or series of pairs of dissimilar metallic plates, and each
bundle of films would become an electric column. In that
case the thermo-magnetic character of the inner surface of
each film would be to its outer surface as bismuth is to anti-
mony; for the current in a pair of those metals flows through
the point of heat from the former to the latter; and the rest
of the circuit answers no other purpose than that of a con-
ductor. When the point of heat is close to the edge of a
transverse fracture of a cylinder of antimony, two, or a very

ew

Homogeneous Bodies ; with illustrative Experiments. 21

few more of these plates or crystalline films may possibly be
the only parts excited; and the rest of the bar assume the
character of a conductor only; in which case the current would
flow, at the point of heat, across the films from the internal
to the external parts of the cylinder; the direction which ex-
periment discovers it to proceed in: besides, it is possible that
the crystalline laminze may individually have different electric
powers.

73. The other hypothesis supposes, that as the crystalline
strata are only in juxta-position, and not very firmly united,
it is possible that the heat applied at any point on the surface
of the cylinder would meet greater obstacles in its progress
whilst passing from film to film than any which it would fall
in with whilst flowing over the surface of those films, or over
. the general surface of the metal: and as heat is well known to
affect electrical phenomena generally, and as it is the exciting
agent in this particular class, it may be supposed that, by its
travelling at different rates in those directions, the electric
powers of the metal may also be put into motion, and assume
certain uniform directions as regards the directions in which
the heat flows with the greatest and least facility *.

74. Experiments with solid Cones of Antimony.— When a
solid cone of antimony, uniformly dense on every side of its-
axis, is made the subject of experiment, the surface near to its
base displays thermo-magnetic phenomena of precisely the
same character as those which have been described in the ex-
periments with a cylinder (60, 61, 62).

75. The cones which I have employed were 4°5 inches
high, and the diameter of the base 225 inches.

76. When any of these cones were heated at any point of
the side near to the base, the current uniformly proceeded
from the point of heat over the surface towards the apex,
and returned on the opposite part of the surface to the base.
This was the direction of the lines of greatest energy, but
like the cylinder, the surface of the cone becomes generally
thermo-magnetic by this process, and the direction of its
forces are easily traced by the compass-needle.

77. Fig. 15. will represent the surface of a cone of antimony
in a state of thermo-magnetic action: the cone is supposed
to be divided into halves from its apex to its base, and in

* These hypotheses are offered merely as conjectures, without any in-
tention of insisting on either of them, until experiment affords more data
in their favour. If I mistake not, however, some of those which I have yet
to describe will bear directly on the subject.

the

22 Mr. W. Sturgeon on the Thermo-magnetism of

the plane of the neutral lines. The same explanation will
apply to this figure as to the cylinder, fig. 13. (65.)

78. It is not necessary that the point of heat be exactly in
the edge of the base to produce the greatest effect, for the
direction of the electric force is still the same, and quite as
energetic, when the point of heat is at some short distance
from the base. Neither is it necessary that any point be made
very hot, unless it can be done very suddenly; for the powers
excited are decisively exhibited when the selected point of
heat is held only for a few moments in the apex of the flame
of the spirit-lamp, and the cone immediately applied to the
compass-needle, before the heat has time to spread, to any
great extent, over the conical surface.

79. When the apex of the cone of antimony is heated, the
electric force is exceedingly feeble, and its direction quite un-
certain. In general, the thermo-magnetic forces displayed by
sheating any point nearer to the apex than to the base are
comparatively insignificant, and their directions not easily
predicted.

80. A cone of antimony which had exhibited the pheeno-
mena already described, was cut in two by a saw, at about
15 from the apex, and parallel to the base. The small cone
operated precisely as the original one, of which it was a part;
but the energies were by no means so powerful.

81. The frustum presented phenomena as if it had been
a complete cylinder, and the electric currents were as de-
cidedly traced when the point of heat was near to the section
as when it was near to the base.

82. When cylindrical bars or cones of bismuth are ex-
perimented with in the manner I have described with an-
timony in those shapes, the thermo-magnetic phenomena are
precisely of the same character, and are regulated by the same
laws; so that whatever phenomena be displayed by the one
metal will also be displayed by the other, provided the cylin-
ders or cones be well cast, and of uniform density on every
side of the axis.

83. In bismuth, however, it sometimes happens that in con-
sequence of an irregularity of crystallization, which it is prone
to assume, there will be one point, and sometimes two, which
when heated will display thermo-magnetic phenomena very
different to those I have before spoken of; but these are irre-
gularities which have nothing to do with the general character
of the phanomena, and but seldom occur.

84. Observations.— Whatever peculiarities there may be in
the crystallization of antimony and bismuth when in igre

oe)

Homogeneous Bodies ; with illustrative Experiments. 23

of other forms, they exhibit arrangements exceedingly similar
to each other when cast into cylinders, which are regularly
and uniformly cooled on every side; and there is so little dit-
ference in the general aspect of a transverse fracture of the
two metals, that were it not for the difference of colour, it
would require some practice to distinguish the one from the
other. From this circumstance it appears highly probable,
that the same cause, whatever it may be, is the fountain of the
thermo-magnetism in both metals.

85. It has been intimated to me by some very scientific
gentlemen, that impurities in the metal may possibly be the
cause of all the thermo-magnetic phznomena which I have at-
tributed to homogeneous bodies; and I must confess that for
some time I had entertained a similar opinion: experience
and observation, however, by no means sanction the conces-
sion. Some other cause than that of impurity in the metal
is unquestionably in active operation ; and to some other cause
we must direct our attention before we can accomplish an
explanation of the phenomena in question. A very small
portion of tin added to bismuth, not only dispossesses it of its
magnificent crystalline ramifications, but also of the superla-
tive display of its natural innate thermo-magnetism: more-
over, that small morsel of tin not only paralyses the thermo-
magnetism natural to bismuth as a homogeneous metal, but
absolutely transfers its thermo-magnetic character as regards
other metals, from one extremity of the range to the other;
so that if pure bismuth be regarded as the most positive metal,
its alloy with tin will be the most negative substance, either
simple or compound, with which we are acquainted ; and
antimony, which has hitherto claimed the negative extremity
of the range, is highly positive to this simple alloy.

66. The thermo-magnetism natural to antimony becomes
completely stagnated when mixed with tin or lead, and the
crystals of the metal become insignificant shapeless specks.
Zinc also, which when in larger masses displays its innate
thermo-magnetism in a degree superior to any other metal
except antimony and bismuth, becomes comparatively inert
by a mixture of tin or lead.

And what perhaps may appear a more convincing fact than
all the rest is, that antimony and zinc, which separately, as
homogeneous bodies, display fine crystalline forms, and also
active thermo-magnetism, will, if mixed together as an alloy,
become robbed of. both those distinguished characters at once,
and the resulting metal appears as compact as the finest
steel.

87. Whatever may be the notions entertained as pelier

the

24 Mr. J. E. Drinkwater on Simple Elimination.

the mass or quantity of metal employed in heterogeneous
thermo-magnetic combinations, I find that in the display of
the thermo-magnetic phenomena of homogeneous bodies, the
quantity employed is an essential consideration; for in several
of the metals, although no trace of thermo-magnetism can be
detected in small pieces, its powers are promptly developed in
masses of considerable dimensions, and the Jaws of its phz-
nomena may be determined with precision. Zinc, when in large
masses, displays thermo-magnetic phenomena in a very ex-
alted degree, but in small pieces hardly any trace of that
power is to be found. Copper is a still more striking instance
of the superior thermo-magnetic powers of large masses.
Those powers could not be detected in a few ounces of the
metal; but in a mass weighing 60 or 70 pounds, they would
become very conspicuous. But a mass of copper of a hun-
dred weight, however heated, would not deflect a needle half
so far as it would be deflected by a single ounce of bismuth
or antimony. Yet, insignificant as these powers are in some
bodies, I have succeeded in detecting them in every metal of
which I had a sufficient quantity at command; and I have no
doubt that they may be discovered in all the metals,

Artillery Place, Woolwich.
[To be continued. ]

II. On Simple Elimination. By J. E. Drinkwater, Esq.*

(1). HE theory of elimination is intimately connected with

the general theory of the resolution of algebraical
expressions, and has engaged the attention of mathematical
writers in a corresponding degree. When the number of
equations and of unknown quantities is considerable, the labour
necessary for the extrication of any one of them becomes very
great, even in the case of simple equations,—a case which is
perpetually recurring in physical investigations. ‘The well-
known rule given for this purpose by Bézout will be found on
trial more laborious than it appears in its concise enunciation,
and no simple demonstration has yet been given of this or
any analogous general theorem. The investigation by Laplace
in the Mémoires de ? Académie des Sciences, 1772, p. 2, which is
there only incidentally introduced, is both diffuse and difficult.
The following method of obtaining the final equations may be
easily identified with those of Laplace, Bézout, and Cramer,
although the coefficients are obtained in rather a different and,
as it is thought, a more convenient form.

* Communicated by the Author.

(2). Let

Mr. J. E. Drinkwater on Simple Elimination. 25
(2.) Let the equations be

A, + X,7+ Yyy+ Z,24+ Mitt ansei(72). =O
A, + Xor + Yoy + Zoz + Tot + «.. (n) = 0
7A, + X.t + Yny + Z,2 + Tit + .. (2) =0

the number of equations and of unknown quantities being 7,
and X,, representing the coefficient of x in the mth equation.

(3.) Write down the series of natural numbers 1 2 34... 7,
and underneath it all the permutations of these 2 numbers,
prefixing to each a positive or a negative sign according to the
following condition :

Any permutation may be derived from the first by consi-
dering a requisite number of figures to move from left to right
by a certain number of single steps or descents of a single
place. Ifthe whole number of such single steps necessary to
derive any permutation from the first be even, that permuta-
tion has a positive sign prefixed to it; the others are negative.
For instance, 4213 ... m may be derived from 1234 ... ”, by
first causing the 3 to descend below the 4, requiring one single
step; then the 2 below the new place of the 4, another single
step ; lastly, the 1 below the new place of the 2, requiring two
more steps, making in all four. Therefore this permutation
requires the positive sign.

(4.) The same permutation may be derived in various ways,
and it is necessary therefore to show that this rule is not in-
consistent with itself: thus the same permutation 4213 ...
might have been obtained by first marching | through three
places, then 2 through two; and, lastly, 3 through one, making
six in all, an even number as before. Without accumulating
instances, it is plain, if g be the smallest number of steps by
which any number 7p reaches the place it is intended finally
to occupy in that permutation, that if p should advance in
the first instance m places beyond this, it must subsequently
return through m places; or, which is the same thing, it must
at a later period of the march, allow m of those which it has
passed to repass it, so that it will regain its proper place, after
the number of steps has been increased from q to g+2m,
which, by the rule, require the same sign as g. ‘The same
reasoning applies to every other figure; and hence the con-
sistency of the rule is evident.

We may, therefore, derive any permutation from any other
by altering the sign of the one chosen, according to the change
made in its order, and generally it will be found convenient
to derive each from the one immediately preceding it.

(5.) We thus get the series +1234 ...+.. 7

— 2134 weveee n
42314 vovoee mM XC.
N.S. Vol. 10, No, 55. July 1831. E Take

26 Mr. J. E. Drinkwater on Simple Elimination.
Take the product XYZT...... (n) of all the letters coeffi-

cient of the unknown quantities, and affect it with the succes-
sive terms of this series (with their proper signs), considered
as a series of indices. We thus form the series

+ Ki YZ, Layese eve (n)

—= a) 2a a etetes (2)

eV 2 Lg woes (2)
&

c
which we shall denote by f{ XYZT ... (m)}

(6.) It will be observed in all the terms of f{ XYZT... (n)}
that the order of the factors remains unchanged, the indices
alone being permuted. If any change is made in the order of
the factors under the symbol, it is obvious that'the only possi-
ble change produced will be a change of sign, which will be-
come positive or negative according to the same rule of signs
already explained among the indices. For instance

S{XIZNT ...(n)} = —f{XYZT ... (n)}

and so of any other. An odd number of single steps by the
requisite number of letters requires the negative sign; an even
number, the positive sign. The entire order of the factors may

n.(n—1)

be inverted in single steps, and accordingly as this

number is even or odd, f{ XYZT...(n)} = + f{(n)...TZYX}.

(7.) The function of n factors f{(7) ...... TZYX} may be
expressed in a series of functions of »—1 factors, by consi-
dering that the permutations of numbers are obtained by
successively adding each at the end of the permutations of the
n—1 others. Attending also to the change of sign necessary
to bring each factor in succession to the end of the product
under the symbol, which is necessary in order to keep the
products of » factors in the same order in each term so ob-
tained,

S{(n) ... TZYX} = X, f{(n—1)...TZY}
—Y,f{(n—1)... TZX}+Z,f{(n—1) ... TYX} —&e.

or inverting the order of the factors under the symbol in every

term,

SF {XYZT...(n)} = +X, ffYZT ...(n—1)}
—Y,f{XZT...(n—1)}+Z, f{XYT... (n—1)} —&e-}
The sign of the first term on the right-hand side of this equa-
tion may be made different from that of all the others, by
making X under the symbol successively occupy every place
from the first to the last, the order of the others remaining
unchanged. xi

e

Mr. J. E. Drinkwater on Simple Elimination. Q7

We thus get,
S {XYZT...(m)} = + X,f{YZT ... (n—1)}

—Y,, {XZT...(n—1)} —Z,f{YXT so. (n—1)}—&e.}

(8.) If any factor in f{ XYZT...(z)}, as X, be divided into
two parts, X = V+ W, the function may be similarly divided,
so that

S{VLW)YZT... @} HS{VVZT ... @} +P{WYZT.... (n)t
placing each part of X in the same relative position (which in
this example is the first) which X itself occupied before the
division.

(9.) If any quantity which does not vary from one equation
to the other, and which therefore is not liable to be affected
with an index, is found under the symbol, it may be consi-
dered a constant coefficient of every term of the developed
function ; and written as such on the outside of the symbol: of
this nature are the unknown quantities themselves, so that for
instance, f{XYaZT ...(n)} = wf {XYZT... (n)5
and so of like quantities.

(10.) Premising these properties of this function, it is easy
to show that the final equations derived from those proposed
in (2) are f{AYZT ... ()} + xf{XYZT ...(n)} =0

f{XAZT ... (a)} + yf {XYZT... (n)s =0
&c

(11.) In the proposed equations let A+ Xx = B, and sup-
pose the theorem proved for »—1 equations, we have,
B, + Yyt+Z,2 + Tit ++ (n—1) = 0
B, + Yoy + Zz + Tot + + (n—1) =0

Byaat Yn1y + Zn® + Trt + eee (n—1) =P)

Be +¥ny +Zn% +7Tné + + (n—1) =0
From the x—1 first of these we get, by the supposition,
S{BZT ... (n—1)} + yf {YZT ... (n—1)} =0
S{YBT ... (n—1)} + zf{YZT ... (n—1)} = 0

&e.

Multiplying the first of these by Y,, the second by Z,, &c.,

we get, by comparison of the result with the last of the pro-
posed equations,

B,f {YZT...(n—1)}—Y,, f{ BZT....(n—1)} —Znf {VBT...(n—1)} —&es = 0
We have already seen (7) that this expression is equivalent

to+ f{BYZT ... (n)}
me S{BYZT ooo (n)} = 0, OF restoring the value of B
=f{(A+Xz).YZT.. (n)}

dividing

28 Professor Encke on the Solar Eclipses

dividing the value of B (8), and withdrawing « from under
the symbol, (9)

S{AYZT ... (n)} + of {XYZT... (n)} = 0

which establishes the theorem to be true for 7, if true for 7—1
equations. The simple equation A, + X,z = 0 evidently con-
forms to the rule, which is therefore true when 7 = 1; it is
therefore generally true.

(12.) The rapidity of this method is best estimated by
examples. Take three equations, in which by the rule

The series of indices is + 123—132+4+231—2134 312—321;
therefore

A,(Y.Z,— YZ) ay A(Y;Z, — Y,Z;) 5 A, Y,Z, "y, Y,Z;)
X,(Y.Z;—Y3Z,)+ X.(Y3Z,—Y,Z3)+ XY, Z,—Y.Z,)
For four equations the series of indices, deriving each from
the one preceding it, is +1234—1243+1342—1324 + 1423
—1432 + 2143—21344+2314—2341 4+ 2431—241343124—
3142 + 3241—3214-+ 34129—3421 4+ 4132—4123 + 4213 —
4.231 +4321 —4312

+z7=0

feeany

A(XYZT) =

Ai { Yo(ZsTs—ZsT3)-+¥3(ZiT:— ZT) + ¥4(ZoTs—ZsTo) } +

Aot Vi( Zila Zo Ta Na Qua a) dV Zee Ce &c.— 9)
X,{ Yo(ZsT,— Z4T3) + ¥5(Z4T2— ZoT4)+ Y4(ZoT3— ZsTo) } +

Xo{ ¥\(Z4T3— ZT) + ¥3(ZiTs—Z4T,) + ¥4(ZsT, — Z, Ts) } +&e.

and since 7 +

III. On the Solar Eclipses and Transit of Mercury over the
Sun’s Disc, in 1832. By Professor ENcKE*,

N 1832 there will be two solar eclipses, and a transit of
Mercury. The latter phenomenon only will be visible at
Berlin. No lunar eclipse will happen.

Solar Eclipse 1833, February 1. App. time of

Berlin.
Beginning on the earth in general.........cseeeeesseevees 85 6!

in 176° 52’ east longitude from Ferro.
8 49 south latitude.

* From the Berlin Astronomical Ephemeris for 1832, page 200—205.
Beginning

and Transit of Mercury in 1832. 29
App. time of Berlin.
Beginning of the central (annular) eclipse ....ss00+4. 9° 13/
in 160°23’ east longitude from Ferro.
8 8 south latitude.
Annular eclipse at NOOD...sscseessereeeesseeseessesereers LL IE
in 223° 25’ east longitude from Ferro.
15 12 south latitude.
End of the central eclipse on the earth.......0eseeere 13° 6
in 280°47’ east longitude from Ferro.
11 51 north latitude.
End of the eclipse on the earth in general ....+-+++0+++ 14 13
in 264° 19/ east longitude from Ferro.
11 10 north latitude.

Visible in the Pacific, the western parts of America, and the
Isthmus of Panama, as also in the eastern parts of New Hol-
land.

Paramatta, Beginning ......... 17°48! app. time of Paramatta.
ni! Ghedad west OVO

Magnitude ........- 4, inches.

Mexico, Beginning.......... 4 28 app. time of Mexico.
Middle....... seoseee’ 5 35 at Sun-set.
Magnitude......+++ 8°7 inches.

Transit of Mercury over the Sun’s Disc, May 4 and 5, 1832.
App. time of
Entrance of the centre of Mercury on the sun’s een:

disc, seen from the centre of the earth, May 4, 21"58/ 20/
Shortest distance 8! O!"5 ..sscecccseeseeeee May 5, 1 22 53
%’s centre leaving the ©’sdisc......... — - 447 8

At the moments of the centre of % entering upon, and
leaving the sun’s disc the sun is respectively in the zenith of
the places whose geographical position is

61° 28! east of Ferro’......-.. 16°18/ north latitude.
319 16 —— eccecsevseee 16 23

All Europe and the greater portion of Africa see the whole
duration, Asia only the beginning, America only the end of
this transit.

In order to calculate the effect of parallax on the time of
beginning and termination for any place in latitude 4, and
east longitude from Ferro 7, we may find the angular di-
stance of this place from a point whose

east longitude from Ferro........6. =A= 166° 18!"8
north latitude.......ssceseserereseerees = B= + 53 57°0
by this formula:
cos £ = sinBsin > + cos Bcos > cos (A—/);
then the actual entrance of %’s centre on the ©’s dise will
take place at the apparent time of the place of observation :
May 4. 19> 54/ 6! 4+ 1— 118'"6 cos §

lor

30 Professor Encke on the Solar Eclipses

For the termination of the transit put
NW = 229° 15) =B! = + 2° 56'0; and calculate
cos ¢' = sin 6! sin ¢ + cos f! cos > cos (A'—I);

and %’s centre will leave the ©’s disc
ic May 5. 25 42! 55” + 2+ 118'"8 cos ¢
apparent time of the place of observation. The contacts of
the limbs will respectively take place about 1’ 33’ sooner or
later.
For Berlin, where
o = 52°31"'2, 1=31° 3!5,
we find cos = +0°3873 cos = —0°5375

3’s centre enters on x. atc, § 21257! 34" § App. time of
==) == .leayes the ©’s disc 446 5 Berlin.

The entrance on the ©’s disc takes place 32° eastward, the
parting from the ©’s disc 87° westward, of the northernmost
point of the ©’s disc.

The duration of the transit of each second in arc of §’s
diameter over the ©’s disc is = 17'3 in time.

Solar Eclipse, July 27, 1832. App. time of
Berlin.
Beginning on the earth in general......seeccesseersereee OF 11’
in 294° 29’ east longitude from Ferro.
10 59 north latitude.
Beginning of the total eclipse on the earth........... 1 6
in 280° 5/ east longitude from Ferro.
12 53 north latitude.
Total eclipse at NOON .....scescsssssscscseccccscssssescesece 2 AT
in 349° 23’ east longitude from Ferro.
24 34°5 north latitude.

End of the total eclipse on the earth......ssccsseereeeee 4 31
in 54°24! east longitude from Ferro.
2 47 south latitude.
End of the eclipse on the earth in general......0. 5 26 -
in 38°11’ east longitude from Ferro.
4 23 south latitude.

The eastern limit of visibility of this eclipse runs through
Europe, from the north coast of Ireland above Greenwich,
along the boundary of Germany and France, to the coast of
Dalmatia. To a country to the westward it will be visible ;
in Germany it will not be visible. The western limit em-
braces the greatest part of North America and a great oe a

out

and Transit of Mercury in 1882. 31

South America. Almost all Africa may see it; but only the
west coast of Asia.
For calculating the beginning and end of the eclipse for
places in Europe the following formulze may be made use of:
Let the longitude of a place from Berlin = / (negative
if west), the corrected latitude = ¢, and let the following
values be calculated :
wu = 1°8816 cos ¢ sin (45° + 2)
v = 1'7773 sin ¢ — 0°6177 Cos ¢ cos (45° + 7)
au! = 0°4926 cos @ cos(45° + 2)
wv = 01617 cos > sin (45° + 2)
m sin M = + 0:2404 — u
m cos M = + 071431 —v
nm sin N = + 1:0862 — w/
ncosN = + 01554 —v/
m sin(M—N) = cost,
where ) must always be taken positive and less than 180°.
The time of beginning and termination of the eclipse will
then respectively be :
sin

h sh —N) =
3h 41 7, 00s (M N) + ia

apparent time of the place of observation expressed in hours
and parts of an hour; the upper sign referring to the begin-
ning, the lower to the termination of the eclipse. The angles
which, at those two moments the respective radius of the sun’s
disc at the point of contact forms with the horary circle of the
sun’s centre, counted from north through east to 360°, will be
respectively iQ=90°+ N+,

and the magnitude of the eclipse in inches will be

= 25.sin3*.

Elements of Solar Eclipses.
Apparent time of Berlin.

February 1. July 27.

® V1» 9f 25's) 2849! 2"7
Longitude of ( and ©.......00064/912° 8! 45!2/124°26! 47!""5
Horary motion of ¢ in longitude 30 24 °8 87 51 ‘1

SG gees sas 2 32-2 2 235
f, OP ccseicaspectsssthatseesel tO). 1 Of D|+0. & Sao
Horary motion of «( in latitude |— 2 49°1/+ 3 30°5
TB PAVAMEME DT faskeesees<nssss oty ees 54 43 °8 G1 14 *4
O'S PATANAR sAistiadass cosesevecess 8 °7 8 °5
(.’S SemidiaMeter ......eeceeeeceeees 14 54°8 16 41 °3

@’s semidiameter ...sscesseeeeeeers 16 15°83 15 47 ‘0
Elements

32 Rey. P. Keith on the Conditions of Life.

Elements of the Transit of Mercury.
Apparent time of Berlin.

Beginning. | End.

May 4 and 5 |225 o! o” 454g! ol
©’s right ascension ...++. wovcee eee 42°21! 500 [42° 38! 19!"9
casscccaswercceIha GO. Gh "lL tO oikiaemec
Horary motion of © in PR UAE IRE Fe oat 5? a eras

sooeti—" lL oe7 |" a toe
©’s northern declination..........|16 18 1°0 |16 22 50°6
0's etetellLowol sock 16 Zo one
©’s horary motion in declination] + 42 °7 |4 42 °6
B's = Se A qoregied 1 '- 1 O8"6
©’s semidiameter ..-ccecescceeeeees 15 52 °4 15 52°3
$’s [distance 1=3"'] DEDy 5°37
©’s parallax ..sececsesseeceeesveeeee 8°5 8°5
8's « scaveusaetblaen lends 15°35 15°38

IV. Of the Conditions of Life. By the Rev. Parrick Kriru,
JS Ors od

HAT is life?—The great variety of definitions by which
physiologists have attempted to exbibit an idea of life,
shows that it is no easy task to do so correctly. The subtile and
untangible character of the subject to be defined is doubtless
the grand cause of the difficulty. Bichat, a French physio-
logist of great celebrity, defined it as follows: “La vie est
Yensemble des fonctions qui resistent a la mort +,”—Life is
the totality of the functions that resist death. It is a trait
from the pencil of a great master, but it is by much too indefi-
nite to exhibit a distinct view of the subject. Functions seem
to be rather the result of life, than to be life itself. But what
is the amount of their resistance? for death finally overcomes
them; and of what class of bodies are they predicable ?—
Richerand defined it thus: ‘La vie est une collection de
phénoménes qui succedent pendant un temps limité dans les
corps organisés{,”—Life is a collection of phanomena that
occur during a limited period in organized structures. But the
boundaries of this limited period are left undefined, and must
consequently be supplied by the imagination of the reader.
They may include even the phenomena of death, for anything
that the definition shows to the contrary. Mr. Lawrence’s

* Communicated by the Author.
+ Recherches Physiologiques. { Traité de Physiologie.

definition

Rev. P. Keith on the Conditions of Life. 33

definition is very brief. It is as follows: “ Life is the active
state of the animal structure*.” This evidently excludes the
torpid state. It excludes also vegetables, which it might
indeed be made to embrace by the insertion of a single word.
But if life may exist even in a state of rest, surely it cannot
be well defined, merely by calling it a state of action.

A writer, who regards the above definitions as savouring
too much of materialism, not to say atheism, gives us another
definition,—the briefest of all: ‘Life is inherent activity +.”
This, it must be acknowledged, is scanty enough: but it
is abundantly comprehensive; for it includes everything of
which inherent activity can be predicated, be it mind, or be it
matter. Yet this is going a great deal further than its author
intended, seeing that it is an approach to the materialism of
which he accuses others. There is an inherent activity in the
movements of the Aurora borealis, the merry dancers of the
North; but it is not life. There is an inherent activity in the
vivid coruscations that dart across the sky, and illuminate the
loaded atmosphere in a night of electrical tempest; but it is not
life. There is an inherent activity in the cause that occasions
the eruption of a burning mountain,—that subterraneous ar-
tillery which melts the solid and primeeval rocks, and upheaves
them in floods of liquid lava; but it is not life. Yet according
to the definition we ought to say that it is life, because it is a
manifestation of inherent activity. Now inherent activity is
not even an entity, but an abstraction. It is not life, but a
property of life. It is not peculiar to living bodies, but is
possessed by many bodies that are thought to be inert. What
are chemical, magnetical, and electrical repulsions and attrac-
tions, if they are not examples of inherent activity ?

It would be presumption in me to attempt to do that which
the above distinguished physiologists, or their more orthodox
criticizers, have failed to do; namely, to exhibit a correct
idea of life, by the selection of a single trait. But as their

* Lawrence On Physiology. 52.

+ Remarks on Scepticism; by the Rev. T. Rennel. 1819.

{Mr. Rennel’s work, not long ago, made some noise in the world. We
believe, however, that this writer is destined to find his place in the temple
of fame among those worthies who in former times insinuated charges of
atheism against Newton and Locke; and we trust that the same freedom
will be claimed for the philosophy of mind, which has of late been ably as-
serted, by Professor Sedgwick and others, for Geology and Zoology. Surely
nothing can be less calculated to confirm the religious belief of mankind than
attempts to persuade them that every discovery or new view in philosophy is
hostile to religion. Can those be justly charged with irreligion who refuse

to assign arbitrary limits to the power of the Deity, as to the properties
which he may confer on matter?

We shall have to notice a recent instance of misrepresentation similar to
that to which we here allude, in our next.—Ep1t.

N.S. Vol. 10. No. 55. July 1831, Ir failure

34 Rev. P. Keith on the Conditions of Life.

failure seems to be attributable, chiefly, to an unnecessary
effort at brevity,—brevis esse laboro, obscurus fio,—perhaps it
might be worth our while to try the effect of a fuller enumera-
tion of particulars. What we lose in point and neatness, we
may gain in perspicuity; and upon this principle I submit the
definition that follows:—Life is that attribute or energy of or-
ganized structures which renders them susceptible to impres-
sions, and enables them to discharge functions. It is real, or
it is potential:—real, if the energy is in operation; as in the
case of an animal in motion, or of a plant protruding its buds
and blossoms ;—potential, if the energy is dormant, as in the
case of an egg not hatched; or of a seed not sown; or, as in
the case of the hybernation, whether of plants or animals. Life
originates in precedent life, and terminates in subsequent
death, which is an extinction of all vital functions, and of all
possibility of vital functions.—Taking this definition, with its
illustration, as our text, we proceed to remark that life in the
exhibition of its phenomena always presupposes the existence
of certain peculiar conditions, previous, concomitant, or con-~
sequent, without which it has never been known to manifest
itself, and of which the most essential are the following,—pa-
rentage, organization, aliment, aération, temperature, death.

Parentage.—There was a time in which philosophers be-
lieved in what was called the doctrine of equivocal generation
—that is generation springing from a fortuitous concourse of
atoms having an appetency to combine themselves into living
forms. ‘This doctrine was taught and maintained by the most
celebrated philosophers of antiquity. Plants were regarded
by Diogenes as being generated from a mixture of earth and
putrid water; the water acting upon the earth, and moulding
it into form*. Plants whose seeds are not apparent were re-
garded by Theophrastus as being propagated by spontaneous
generation, because some tribes of animals were thought to
be so propagated +; and parasitical plants were regarded as
springing from some corrupted matter generated on the tree
producing them{. The poets of antiquity had the same fic-
tions. Ovid replenishes his post-diluvian world with animals
that sprang up out of the earth sponte sua, excited by heat
and moisture§. The philosophy of the dark ages was not
likely to correct the errors of antiquity; and when a better
philosophy was introduced, at the time of the revival of learn-
ing, it could not be expected to correct them all at once.
Even Bacon, the great reformer of philosophical methods,
still gave his sanction to the doctrine of equivocal generation,

* Theophr. Teg: Puta iarogias, lib. iii.

t+ Tlegs Qutwy airiy, lib, i.

} bid. lib. v. § Metamorph, lib, i.
as

Rev. P. Keith on the Conditions of Life. 35

as may be seen by perusing his Sylva Sylvarum. ‘The mosses
that grow on trees he regards as being nothing more than a
sort of excretion which the tree cannot assimilate; and the
misletoe he represents as being produced, not from seed, but
merely from superabundance of nourishment.

Yet the truth of the doctrine began to be at last suspected,
and subjected to the test of observation and experiment. It
was a scrutiny which it could not stand, and beneath which it
fell refuted. The credit of the retutation is due partly to
Harvey, who contended that all animals spring from an egg
deposited by a parent,—omne animal ex ovo; and partly to
Francisco Redi, an Italian philosopher and physician, whose
experiments are well known, together with their result;
namely, that there is no such thing as a generation of insects
from putrefaction. Similar investigations were applied to the
vegetable kingdom by Malpighi and others, with similar re-
sults, demonstrating that all plants spring from seed, the pro-
duce of a parent,— omnis planta e semine. In short the doctrine
of equivocal generation came into universal disrepute; and
the stories of showers of frogs that fell from the clouds, and
of armies of insects engendered by the east wind, and wafted
on its wings, together with the marvellous account of a plane
tree that sprang up spontaneously out of a brazen tripod, as
related by Theophrastus, were no longer credited.

Such was the triumph of truth over error. Yet the very
progress of the science that achieved it gave rise to new
doubts. In the advance of microscopical discovery, a new
world was laid open to the view of man, namely, that of the
animalcula infusoria and spermatica. ‘The most successful of
the earlier operators in this department were Leuwenhoeck,
Needham, and Swammerdam. Leuwenhoeck estimated the size
of the smallest of these minute animalcules, and found that
upwards of 1,000,000 of them might be contained in a space
not larger than that occupied by a grain of coarse sand *.
Concerning their origin every philosopher had his own opinion.
Some regarded them as being generated by parents of the
species, rather from analogy, than from any direct proof, which,
in objects so minute, it must be next to impossible to obtain.
Buffon regarded them as being, not the product of generation,
not germs or embryos, not either animals or vegetables, but
merely organic and moving particles proper to compose a
living being.—If this were really the case, the species or vari-
eties of animalcula would be interminable, as there would be
no end to new combinations of organic particles, and no cer-
tainty of finding tomorrow the species you may have met

* Phil, Trans. Abridged ; vol, ii, 377. and vol. iii, 203,
KF 2 with

36 Rev. P. Keith on the Conditions of Life.

with today. But the contrary of all this is the fact. The
species are not interminable, but circumscribed, and in some
of them the mode of propagation has been actually ascertained.
But animalcules have been found in infusions that have been
boiled, roasted, and even subjected to the heat of a blowpipe ;
and this has been regarded as a proof that they have not pro-
ceeded from anything possessing life. Yet some species of
seeds will survive even the action of boiling, and their germs,
as we may suppose, are not less vivacious than themselves ; and
if the infusions in question were deprived of everything vital,
whence came the animalcules?—They must have come from
without. They must have penetrated the containing vessels;
—a fact which cannot be admitted without due evidence.
Fray affirms that he found animalcules in mineral mixtures *;
and the same doctrine has been again advanced by Brownt,
who finds them in rock, glass, ashes, soot, when ground to
an impalpable powder and mixed with a little water. But as
this question may be said to be yet sub judice, we will adopt
the proposition of Cuvier, and say with him, “ La vie ne nait
que de la viet,”— Life originates only in life.

This proposition has been a good deal carped at, unfairly,
as we think, by Barclay§, who disapproves of the doctrine
which it contains altogether, and asks whether the first indivi-
dual, or the first pair of any species, could have come into ex-
istence in this manner ?—The answer is ready. Cuvier’s ob-
ject was not that of tracing phenomena to their first causes,
which may lie concealed for ever from human view, but merely
to such causes as fall within the sphere of human observation,
and are cognizable by human means. This is philosophy ;
this is physiology. ‘The study of a first cause is religion; and
our knowledge of it is derived, chiefly, from revelation. We
do not say that it must necessarily be excluded from physio-
logical research; but if the individual inquirer chooses to ex~
clude it for the purpose of keeping separate two subjects that
are perfectly distinct, he is not therefore to be regarded as an
atheist. What light has Dr. Ure thrown on geology by his
boasted introduction of the agency of a first cause ?— But, says
Barclay, what are we to make of the animalcula infusoria ?
It has not been proved that they are the product of generation ;

* Essai sur U Origine des Corps organists : Barclay.

+ [Justice to Mr, Brown requires from us a remark on this point. It will
be found, on perusing that gentleman’s papers on Active Molecules (Phil.
Mag. and Annals, N.%., vol. iv. p. 161, vi. p. 161), that he nowhere ascribes
animal life to them, as the cause of their motion, and consequently ought
not to be stated as regarding them to be animaleula. In the latter paper,

indeed, he has expressly denied that he considers the active molecules to
be animated.— Enir. |

t Legons d'’Anat. Compar,: Barclay. § On Life and Organization. ng
anc

Rey. P. Keith on the Conditions of Life. 37

and yet they are evidently endowed with life.—To this we
will reply by the following question. Has it been proved
that they are not the product of generation?—If the higher
orders of animals, the animais with which we are best ac-
quainted, are evidently the product of generation, ought we
not to conclude from analogy, that other and inferior orders
of animals, with which we are less acquainted, are the product
of generation also? or at the least of some process analogous to
it, and leading to a similar issue. On this ground we rest
satisfied of the legitimacy of Cuvier’s conclusion.

Organization.—A very general and very good division of
the bodies existing in nature, is that by which they are dis-
tributed into two primary classes of organized and unorganized
productions. If we suppose a gradation by which all natural
bodies are placed according to their rank in the scale of being,
the unorganized substances will be found at the bottom. They
exhibit no indications of life, no susceptibility to impressions,
no sympathy of parts, no functions. Still they possess a de-
finite number of properties by which they are readily charac-
terized. Their properties are physical or chemical ;—gravity,
elasticity, mobility, affinities, attractions, repulsions. ‘They
display also a gradation among themselves. Some of them
are found merely in shapeless lumps that accident seems to
have thrown together, and that accident may again disperse ;
—masses of rock, masses of minerals. Others are found to pre-
sent themselves in regular and symmetrical forms, whether in-
dividually or in the aggregate ;—crystals, masses of crystals.
If we regard the fabric of the earth which we inhabit, we find
that it is moulded into an immense and globular mass; but it
is destitute of all organization, as are the fluids with which it
is watered, and the gases with which it is surrounded. The
same remark may be extended, as we presume, to the heavenly
bodies also;—the sun, the stars, the planets, and their sa~
tellites.

Organized bodies form the second class. They stand higher
in the scale of being, and are endowed with nobler properties.
They are the sole receptacles of life, which has never yet dis-
played itself except in such fabrics. ‘They consist, in their
living state, partly of solids, and partly of fluids in motion.
The fluids are the materials out of which the solids have been
formed,—chyle, blood,—sap, proper juice; or they are secre-
tions, or exhalations, or excrements coming from the solids ;
—bile, urine, perspirable matter,—gum, nectar, perspirable
matter. In the aggregate they form a fabric which is com-
posed of a definite system of individual fabrics or organs,
which constitute in their assemblage an individual a

plant,

38 Rev. P. Keith on the Conditions of Life.

plant, an animal. An organ is a fabric adapted by its struc-
ture to the performance of a function;—a hand, a foot, a leaf,
—-prehension, progression, aération. Bichat has remarked
that the organs destined to the higher functions of the higher
orders of animals—the organs by which they communicate
with the external world—are more symmetrical in their form
than other organs, and many of them double, as the eyes, the
ears, the hands, the feet; or divisible into two corresponding
halves, with a manifest medial line,—as the brain, the tongue.
The higher the function the greater the symmetry of the or-
gan *. We may extend this remark to vegetables also. It will
not be found to apply so generally, nor in the same degree; but
it is easy to discern traces of the fact. The leaves and petals
are among the most important of all vegetable organs, and they
show this peculiarity very conspicuously. ‘They are divisible
into an anterior and posterior surface; and into a right and
left side separated by the intervention of a midrib. ‘The in-
terior organs of the flower may be regarded as divisible into
two equal and similar halves; the spongiolz of the radicles
may be regarded in the same light; and perhaps the beautifully
twisted form of the spiral threads should be regarded also
as an example of the symmetry in question. An assemblage
of several organs all concurring to the production of a single
result constitutes an apparatus,—the visual apparatus, the di-
gestive apparatus, the lacteal apparatus. An assemblage of
organs possessing the same or a similar structure constitutes
a system,—the vascular system, the osseous system, the nervous
system. The immediate constituents of organs are tissues,—
the cellular tissue, or the fibrous tissue.

Of all living bodies whether plants or animals, the principal
mass is composed of the cellular tissue. It enters into the
composition of almost every organ, and binds and cements
together the fibres that pervade it. Particularly, it forms
the principal mass of succulent plants, and a notable portion
of many parts of woody plants. It abounds in succulent
fruits, and in the lobes of all seeds. It consists of clusters
of little cells or vesicles containing an inclosed fluid, which
Grew compared in their aggregate aspect to the bubbles formed
upon the surface of liquors in a state of fermentation.—The
foetus seems a homogeneous mass of cellular tissue filled with
a gelatinous fluid. As the organs begin to show themselves
this mass becomes more condensed. As the bulk of the organs
increases, the proportional bulk of the tissue diminishes. It
is the receptacle of lymph and of fat, and is at all periods of

* Recherches Physiologiques, par Nav. Bichat. 8.
life

Rev. P. Keith on the Conditions of Life. 39

life that on which depends the plumpness or embonpoint of the
individual*.

Of all living bodies whether plants or animals, a notable
portion is composed of the fibrous tissue. The fibres are
arranged in groups or bundles passing longitudinally through-
out the whole extent of the organ, as in the slip of Aspidzwm
Filix-mas ; or in the nerves, muscles, and tendons of the ani-
mal fabric. When viewed superficially, a group appears to
be merely an individual fibre; but when inspected minutely,
and under the microscope, it proves to be made up of fibres
smaller and minuter still, firmly cemented together and forming
in the aggregate a strong and elastic thread, but capable of
being split into a number of component fibriles, till at last
they become so fine that you can divide them no longer. But
in some organs they are arranged in thin plates or lamine,
as in the net-work of the cortical and woody layers of plants;
and in the composition of the sclerotica and periosteum of
animals +.

Every organ is invested, and if admitting it, lined, with an
envelope of fibrous or of cellular tissue; and every living in-
dividual is enveloped with a covering of bark or of skin, or at
the least with a fine epidermis. If the tissues are themselves
examined with a view to ascertain the elements of their own
composition, they will be found to consist of fine films or f:briles,
which seem to be themselves composed of multitudes of minute
and gelatinous globules closely compacted together, and dis-
tinguishable only by the microscope. Their diameter is re-
presented as not exceeding the ,,),5th part of an inch; but
their existence is by some doubted. Beyond this, the analysis of
the dissector cannot go. Here his anatomy ends. If he pro-
ceeds to chemical analysis, he will find that the proximate prin-
ciples of the animal solids are chiefly albumen, fibrin, gelatin ;
the remote principles being azote, oxygen, hydrogen, carbon,
with the azote predominating t.

Of the vegetable solids he will find that the proximate
principles are chiefly albumen, fibrin, gluten, sugar, gum,
extract; the remote principles being carbon, hydrogen, oxy-
gen, with the carbon predominating §. When the proximate
principles of animals, albumen, fibrin, gelatin, are converted
artificially from a fluid to a solid state, as by the action of
heat or of other chemical agents, multitudes of minute globules,
similar to those of the blood, are said to be developed in the

* Anatomie Générale, par M. Bichat. 98.
+ Anat. Générale, tom, ii. 251. t Magendie, by Milligan. 10,
§ Davy’s Agricultural Lectures,
niass.

40 Rey. P. Keith on the Conditions of Life.

mass*. It is a presumption in favour of the globulous struc-
ture of ultimate, living tissue.

Do the vital powers reside in the fluids, or in the solids, or
in both? Some physiologists would confine them to the solids.
But if the solids originate in the fluids, how can the fluids
themselves be destitute of vital powers? They would thus
present the singular anomaly of communicating that which
they do not possess. Mr. J. Hunter believed in the vitality
of fluids; or, at the least, in the vitality of the blood. But
Blumenbach can see no ground for adopting this opinion.
If you grant vitality to the blood because it is the material
out of which the living solids are formed, as well, says he, may
you grant it to water because the Nymphez and many other
remarkable plants are nourished by it}. We do not think
that the case is fairly put. Blood is an elaborated fluid fit for
immediate assimilation, and the vegetable fluid corresponding
to it is not water, but proper juice.

Bichat is also of opinion that fluids do not possess vitality,
because they are incapable of contraction and of sensibility.
Fluids he regards as merely passive, and solids only as active }.
But fluids are stimulants, or exciters at least, and thus they
act upon solids. The blood stimulates the heart to action,
and ardent spirits stimulate the brain. After all, Bichat admits
that the fluids begin to acquire animalization and vital proper-
ties in the course of their elaboration in the system. The chyle
is more animalized than the alimentary mass; the blood than
the chyle. This is granting enough to sanction the vitality of
some fluids; and the vitality of all fluids is not contended for.
But why should we doubt the possibility of endowing a fluid
with vitality; or in what respect is it more easy to conceive a
solid endowed with it than a fluid? The rudiments of the
solids exist already in the fluids, that is, in the fluids elaborated
for nutrition; so that the former can be nothing else than a
more compact aggregation of the minute and semi-organized
globules of thelatter, effected by the agency of the living powers
of the plant or animal in some specific and determinate man-
ner. The fluids of the human body are represented by Bichat
as being to the solids in the ratio of 9 to 1; and the fluids of
vegetables as being to the solids in a greater ratio still. Many
of them contain globules of a regular figure and magnitude,
particularly the blood, lymph, and chyle; and the spermatic
fluid contains millions of animalcules. The fluids yield by
chemical analysis the same principles as the solids §.

[To be continued.

* Edwards Del Influence des Agens physiques sur la Vie.
+ Blumenbach’s Physiology, by Elliotson. 21.
t Anat. Génér, 24. § Magendie, by Milligan. 14.
V. Proceed-

Varig
V. Proceedings of Learned Societies.

ROYAL SOCIETY.

May 3.— ih hee was read, “ On the effect of Water, raised to
Temperatures moderately higher than that of the At-
mosphere, upon Batrachian Reptiles.” By Marshall Hall, M.D., &c.

Dr. Edwards had found, by aseries of experiments, that the batra-
chian reptiles, when immersed in hot water, live for a shorter time in
proportion as the temperature of the water is higher; and that at
108° of Fahrenheit they die almost instantaneously. ‘The author of
the present paper observes, that the extinction of life in these cases is
owing to a cause of a more immediately destructive agency than the
mere suspension of respiration : he finds that if only the head of the
animal is placed under water of 120°, the animal struggles, but soon
ceases to move ; but if the spine as well as the limbs be immersed,
convulsions supervene, and the muscles become rigid : in both cases
the action of the heart continues. If one of the limbs, which after the
extinction of sensibility still remains flexible, be separated from the
body, and placed in water of 120°, its muscles contract and become
rigid; this effect taking place first in the superficial, and next in the
deep-seated muscles. When the nerve, separated from the other
parts, was alone placed in hot water, the muscles were not affected :
and when the muscles had been made to contract by hot water, they
were no longer capable of being affected by irritations applied to the
nerve. The heart removed from the body, and placed in hot water,
gradually contracted and remained rigid. Hence the author concludes
that the death of the animal, when occasioned by the sudden applica-
tion of heat to the surface, is not owing to asphyxia, but to a posi-
tive agency, destroying the functions of the nervous and muscular
systems ; the muscles of involuntary motion being affected in like
manner with those of voluntary motion.

A paper was read, entitled an “ Account of a new mode of pro-
pelling Vessels.” By Mr. Wm. Hale. Communicated by Richard
Penn, Esq. F.R.S.

The author ascribes the want of success which has hitherto attend-
ed all attempts to propel vessels by a discharge of water from the
stern, to the injudicious plan of the apparatus employed, and not to
any defect in the principle itself: for he considers that the reaction
upon the vessel from which a volume of water is thrown, depends in
no degree on the resistance it meets with from the medium into
which it is ejected, but simply upon the momentum given to the mass.
The author proposes to accomplish the object of propelling water by
means of an instrument having the form of an eccentric curve, re-
sembling the spiral of Archimedes, made to revolve on an axis. The
resistance offered to the water in which it is immersed results from
the different distances of the two ends of the spiral propeller from the
axis. This propeller acts in a box having also a somewhat spiral
form, and the space between the two ends of the spiral, after descri-
bing one turn, is open to allow of the exit of the water driven out
by the propeller. The bottom of the box has a circular aperture, of

N.S. Vol. 10. No. 55. July 1831. G which

42 Royal Society.

which the radius is equal to the distance of the shorter end of the
propeller from the axis. The water within this circle meets with no
resistance until it arrives at the line joining the two extremities of
the propeller, when it is immediately acted upon by the eccentric
curved surface of the propeller.

A paper was read, entitled, “ Additional thoughts on the use of
the Ganglions in furnishing Electricity for the production of Animal
Secretions.” By Sir Everard Home, Bart., F.R.S.

The author considering animal heat as depending on the ganglions,
infers from the analogy of the structure of the abdominal ganglia with
the electrical organs of fishes, that animal heat arises from the elec-
tricity supplied by these ganglions.

May 12.—A paper was read, “On a peculiar class of Acoustical
Figures ; and on certain forms assumed by groups of particles upon
vibrating elastic surfaces.” By Michael Faraday, Esq., F.R.S.,
M.R.I., Corresponding Member of the Royal Academy of Sciences
of Paris, &c.

When elastic plates on which sand has been strewed are thrown
into sonorous vibrations, the grains of sand arrange themselves in
lines which indicate the quiescent parts of the plate, and have been
called the nodal lines. This fact was discovered by Chladni, who
also observed that the minute shavings cut by the edge of a glass
plate from the hairs of the violin bow employed to produce the vi-
bration, collected together on those parts of the plate that were
most violently agitated, that is, at the middle of the lines of oscilla-
tion, or portions into which the plate is divided by the nodal lines.
The same phenomenon is exhibited by lycopodium, or any other
very light and finely divided powder. ‘This subject was investi-
gated by M. Savart, who, ina paper read to the Royal Academy of
Sciences at Paris in the year 1817, endeavoured to account for this
latter class of phenomena by deducing from the primary divisions
of the parts of vibrating bodies, certain secondary modes of divi-
sion, comprising parts that remain horizontal during every stage of
the vibration, and which therefore may admit of the settlement there
of light powders, while heavier powders can be stationary only at
the points of absolute rest.

This explanation not appearing to the author to be satisfactory,
he made a great number of experiments, which are detailed at length
in the present paper, showing that the immediate cause of these
motions exists in the surrounding medium, and is to be found in
the currents arising from the mechanical action of the plate, while
vibrating upon that portion of the medium which is in contact with
the plate. These currents are directed from the quiescent lines
towards those parts where the oscillation is the greatest, and meet-
ing from opposite sides at these central points, thence proceed
perpendicularly from the vibrating surface to a certain distance ;
and finally, receding from each other, return again in a direction
towards the nodal lines. The combination of these motions consti-
tutes vortices carrying with them any light particles which may lie
in the way of the currents. While in motion, the powders sustained

by these vortices appear in the form of clouds, the particles of sae
ave

Royal Society. 43

have among themselves an intestine motion of revolution, rising in
the centre of the heap, and rolling down again on the outer sides.
The powders are collected in the same situations on the vibrating
plate, although the plate may be considerably inclined to the hori-
zon, and remain there even when the inclination is so great as to
prevent grains of sand from resting on the nodal lines. A piece of
gold leaf laid upon the plate was raised up in the form of a blister
at that part which corresponded with the centre of the clouds, even
to the height of one-twelfth of an inch.

On attaching small pieces of card to different parts of the surface
of the vibrating plate, the currents of air are modified in various
ways, as shown by the different positions of the clouds, and the pro-
duction of partial accumulations of the powders. When a tuning-
fork is made to vibrate, and a little powder of lycopodium is
sprinkled over it, the powder collects into clouds on the middle of
the upper surface, and also forms heaps along its sides, exhibiting
in a striking manner the intestine revolution of their particles. These
effects are also well illustrated by vibrating membranes ; for which
purpose a piece of parchment was stretched, and tied while moist
over the mouth of a funnel, and made to vibrate by means of a horse-
hair, having a knot at the end, passed through a hole in the centre
of the parchment; the hair being drawn between the finger and
thumb, to which a little powdered rosin was previously applied.
The phenomena were still more conspicuous when the parchment
was made to vibrate under a glass plate held near it. When the
interval between the membrane and the glass plate was very small,
the whole of the powder was sometimes blown out at the edge, in
consequence of the vibrating membrane acting as a bellows.

Reasoning from the theory which the author had framed in ex-
planation of these phenomena, he conceived that if the currents
were weakened by placing the apparatus in rarefied air, they would
no longer be capable of sustaining the light powders, which would
then be collected, like the heavy powders in air, at the nodal lines.
Ina denser medium, such as water, the reverse should happen ; the
heavy powders should be carried along by the more powerful cur-
rents then produced, and would accumulate in the vibrating parts.
All these conclusions were found to be fully verified by actual ex-
periment.

May 19.—A paper was read, entitled, “« A Table facilitating the
Computations relative to Suspension Bridges.” By Davies Gilbert,
Esq. V.P. R.S.

The table here communicated is supplementary to those accom-
panying the paper “On the Mathematical Theory of Suspension
Bridges,” which was published in the Philosophical Transactions for
1826, and is deduced from the first of the tables there given ; but
admits of a far more ready application than the former to all cases
of practical investigation. It consists of five columns, exhibiting
respectively the deflections or versed sines of the curve; the lengths
of the chains; the tension at the middle points, or apices of the
curve ; the tensions at the extremities ; and the angles made by the
chains with the horizon at the extremities.

G2 A paper

44 Royal Society.

A paper was read, entitled, “ Researches in Physical Astro-
nomy.” By J.W. Lubbock, Esq. V.P. and Treasurer of the Royal
Society.

The first part of this paper relates to the theory of the moon.
The method of solution pursued by Clairaut consisted in the inte-
gration of differential equations, in which the true longitude of the
moon is the independent variable: the time is then obtained in
terms of the true longitude; and by the reversion of series, the lon-
gitude afterwards obtained in terms of the time. This method
is the one adopted by Mayer, Laplace, and Damoiseau. The au-
thor has been led, by reflecting on the difficulties of this problem,
to believe that the integration of the differential equations in which
the time is the independent variable would be at least as easy as
the former process ; and it would possess the advantage of employing
the same system of equations for the moon as for the planets, The
lunar theory proposed by the author, and developed in this paper,
is an extension of the equations given in his former Researches in
Physical Astronomy, already published in the Philosophical Trans-
actions; by including those terms, which, in consequence of the
great eccentricity of the moon’s orbit, are sensible; and by sup-
pressing those which are insensible from the great distance of the
sun, the disturbing body. He has not yet attempted to obtain nu-
merical results, but proposes at some future time to engage in their
computation.

In the second part of the paper, he investigates the precession of
the equinoxes, on the supposition that the earth revolves in a re-
sisting medium ; an investigation which may also be considered as
a sequel to the author’s last paper on Physical Astronomy. The
effects of the resistance of such a medium is to increase the latitude
of the axis of rotation (reckoned from the equater ef the figure)
till it reaches 90°. Such is now the condition of the axis of the
earth: but as the chances are infinitely great against this having
been its original position, may not its attainment of this position be
ascribed to the resistance of a medium of small density acting for
a great length of time,—a supposition which may account for many
geological indications of changes having taken place in the climates
of the earth? The operation of such a cause would be also sen-
sible in the case of comets: and the accuracy with which the ec-
centricity of the Halleian comet of 1759 is known, would appear to
afford a favourable opportunity of verifying this hypothesis.

A paper was read, entitled, “An Account of the Construction and
Verification of the Imperial Standard Yard for the Royal Society.”
By Captain Henry Kater, F.R.S.

The scale of the standard, of which an account is given in this
paper, is constructed in the manner described in the Philosophical
Transactions for 1830. The support is of brass 40 inches long,
17.5 inches wide, and 0.6 of an inch in thickness. A brass plate
seven-hundredths of an inch thick was made to slide freely upon the
support in a dove-tail groove formed by two side plates, and was
then fixed to the support by a screw passing through its middle.
This plate carries the divisions, which are fine dots upon gold aie

et

Geological Society. 45

let into the brass; the scale is divided into inches, and there is one
inch to the left of zero, which is subdivided into tenths. The scale
is the work of Mr. Dollond. The paper is concluded by an account
of the precautions which were taken to ensure the accuracy of the
plane surface on which the bar rested, while the comparisons were
made with the microscopic apparatus described in the Philosophical
Transactions for 1821. The results are given in a table.

A paper was read, entitled, “An Experimental Examination of
the Blood found in the Vena Porte.” By James Thackeray, M.D.
Communicated by Sir Astley Cooper, Bart. V.P.R.S.

The author, in the course of an inquiry into the properties of the
blood, was led to notice some peculiarities in the contents of the
vena porte, and to investigate this subject more minutely. The
results of the experiments which he made for this purpose are
chiefly the following. The blood contained in the vena portz is
darker than that of the other veins, inclining more to a ruddy hue
than to the Modena red. Being less homogeneous, it has the ap-
pearance of being less perfectly elaborated. Its specific gravity was
found to be very variable, but it is in general less than ordinary
venous blood. It coagulates much more quickly, and contains a
larger proportion of serum, but a much smaller proportion of al-
bumen, than blood taken from other veins. The serum obtained
from it is redder than common serum, in consequence of its retain-
ing much of the colouring matter of the blood: it has also a greater
specific gravity, and yields, on exsiccation, a greater weight of solid
matter. On the application of heat, it concretes more quickly, but
much less completely, than blood from the jugular vein ; which pe-
culiarities are attributed by the author to the different state and
imperfect formation of the albumen contained in it. The crassa-
mentum of the blood from the vena porte does not expel its serum
so fully as blood from other vessels ; but it remains a soft mass,
unless artificial means be employed, and it yields a considerably
smaller quantity of fibrin.

GEOLOGICAL SOCIETY.

May 11th, and 25th.—At the meetings held on these evenings, a
paper was read, entitled “‘A Sketch of the principal Secondary and
Tertiary Formations of Germany,—by Roderick Impey Murchison,
Esq., Pres. G.S., F.R.S. &c.”

This communication is derived from a series of memoranda which
the author has extracted from note books, written as he passed through
various parts of Germany in the last three years ; and he presents it
to the Geological Society in the hope, that it may rouse the atten-
tion of his countrymen to the increasing geological interest of that
country, and to the various valuable native publications which de-
scribe its subdivisions. He endeavours to point out, in ascending
order, all the German formations from the surface of the carboniferous
rocks up to the newest tertiary deposits, showing, as far as is possible,

their analogies and discrepancies when compared with those of
England;

46 Geological Society.

England; and entering into detail on such points only as fell directly
under his own observation. He refers for an account of places not
visited by himself, to the general work of M. Boué, and to various
local authorities.

In citing, with much praise, the recently published maps and sec-
tions of Hoffmann on North-Western Germany, the English inquirer
is cautioned against the general application, in Germany, of that part
of the table of superposition, in which the coal measures are desig-
nated as some beds, subordinate to a vast thickness, 3000 or 4000
feet, of red sandstone and conglomerate, the whole of which are
grouped by Hoffmann under the one term of rothe-todte liegende. It
is shown, on the contrary, that, however well this classification may
apply to a small part of Germany, it is by no means the rule in the
N.E. part of Bavaria, in Bohemia, and Westphalia; in all of which
countries there are successions in the carboniferous series, very simi-
lar to those in England, accompanied with large expansions of moun-
tain and transition limestones. The author, therefore, adopts that
view of Professor Sedgwick which restricts the name of rothe-todte-
liegende to those sandstones and conglomerates which surmount the
carboniferous series, and separate it from the kupfer-schiefer and
magnesian limestone.

In describing the kupfer-schiefer and overlying limestones, zech-
stein, &c. the author cites M. Klipstein’s late work on the Wetterau
and Spessart; and he confirms the conclusions already drawn by Prof.
Sedgwick in his comparison and identification of the same strata
with the magnesian limestone of England.

New red sandstone series—In this vast group the author, following
the classification of Humboldt, Hoffmann, and other modern writers,
points out that in Germany it is divided into three great systems ; an
inferior and a superior red sandstone, each abounding in variegated
marls, the one separated from the other by that great limestone for-
mation called the “‘ muschelkalk”’. The lowest system or biinter sand-
stein being described first in general terms, detailed sections of it are
then given from Alsace, where the author found it to be capped by
muschelkalk, and charged with some peculiar plants, chiefly Conifer
and Ferns, first discovered in it by M. Voltz, and since described by
M. Adolphe Brongniart ; he likewise found in it many bivalve and
univalve shells, approaching very nearly in character to those of the
muschelkalk and superior formations, but, as well as the plants,
differing essentially from any fossils of the magnesian limestone and
inferior formations. The frequent occurrence of salt and gypsum is
noticed—numerous instances of great dislocations and elevations of
the beds are enumerated, particularly on the northern flank of the
Hartz—in the south of Hanover, a section across the Thuringerwald,
by a new road, is given—and places are cited where the red sandstone
is prismatized, in contact with trappean or igneous rocks.

Muschelkalk.—This most important limestone formation, averaging
in thickness from 600 to 800 feet, is seen in Wirtemberg, Bavaria,
Gotha, and Hanover, to rest upon the biinter sandstein, and to be

capped

Geological Society. 47

capped by keuper. A triple subdivision of the muschelkalk, established
by Hausmann, is spoken of, in which each subdivision is characterized
by its peculiar fossils.

For a full account of the muschelkalk of Wirtemberg the reader is
referred to Alberti’s Konigsreich’s Wiirtemberg, by which it is shown,
that all the salt-mines of that kingdom occur in this formation. The
Saurian remains found in it by M. Jager consist of Plesiosaurus,
Ichthyosaurus, and an unknown reptile, in addition to which Count
Miinster has procured from the same limestone, the jaws and teeth of
a crocodile, plates of a turtle, many parts of fishes of new genera, &c.
By way of comparison with the muschelkalk of Germany, the author
gives a sketch of the same formation in Lorraine, where the fine col-
lection of M. Gaillardot of Luneville is specially spoken of, in which,
in addition to many Sanrian remains, there are bones of gigantic
tortoises, with the characteristic fossils of the formation (such as
Ammonites nodosus, A. biplicatus, Mytilus socialis (Schlot.), Encrinites
liliformis), and two species of the remarkable fossil called Rhyncolites.

Keuper,—This formation of purple, red and green sandstone and
marls is stated to be of enormous thickness at Stuttgart, where it is
seen reposing on muschelkalk, surmounted by lias; and a detailed
section at that place is given, in which are specified the beds of red
sandstone containing the greatest number of the fossil plants de-
scribed by M. Jager. Calamites are mentioned as being found in the
lower quarries, and in the upper certain Equisetaceous plants, which
very much approach to the characters of the plants of the lias and
oolitic series of England : 2 new species of Saurians, (Cylindricodon
and Cubicodon of Jager,) are also mentioned. The exact range of this
formation in the North of Germany is to be found in Hoffmann’s
New Maps.

The author believes that the upper red and green marls of the En-
glish series are the true representatives of the kewper, and that the
only group in the red sandstone series of Germany hitherto un-
observed in England, is the muschelkalk ; and he invites geologists
to attempt to discover the equivalent (however feeble) of that lime-
stone formation, by seeking for it as a bed of separation between
the upper red marls and the lower new red sandstone of this island.

Lias,—The lias marls and gryphite limestone, with many identical
species of English fossils, are stated to be well developed in Wirtem-
berg, the north of Bavaria, Hanover, Westphalia, &c.

After instituting a close comparison between the fossil contents of
the lias of Wirtemberg and that of England, in Saurian and other ani-
mal remains, drawn chiefly from the work of M. Jager, the author gives
in great detail, a section on the right bank of the Maine at Banz, near
Coburg, a spot to which his attention was first directed by M. de Buch,
where the beds are very analogous in mineral characters and suc-
cession to those of the coast of Whitby, and where the most asto-
nishing profusion of fossils has been collected through the indus-
try of MM. Theodori and Gezer, all of which now ornament the
Ducal museum of Banz. Amongst these are 6 species of Ichthyo-
saurus, 5 of which are known in England (Ichthyosaurus cai

eing

48 Geological Society.

being the most abundant) :—Fishes, 6 or 7 genera, (Dapedium,
Clupza, Cyprinus, &c.)—Pterodactylus— Crustacea, 2 species, Ammo-
nites, 11 species, of which about two-thirds are figured in Sowerby’s
Mineral Conchology—Belemnites, 12 species, Scaphites, Nautili and
numerous other univalves as well as bivalves common to the English
lias. Some of the higher beds are described as containing Trochi,
Helicine, and Spirifere. Pentacrinites Briareus of the English lias
is likewise stated to be of common occurrence, and that a species of
Fungia, a genus of corals hitherto unobserved in the lias of England,
also occurs.

Inferior Oolite.—The inferior oolite of Germany is next described, as
being quite analogous to that of the Hebrides and the coast of York-
shire, viz., a great arenaceous formation, for the most part highly fer-
ruginous. It contains many characteristic British fossils, and uni-
formly caps the lias throughout Wirtemberg, Bavaria, Hanover and
Westphalia, and in some parts (near Banz and in Franconia) it
passes up into an iron-shot, true oolite (Oolitischer eisen-stein of
Minster).

The ferruginous grits of this formation, it is stated, are not to be
confounded with the lias grits, from which they are clearly distin-
guished both by fossils and superposition.

A very detailed section is then given of all the strata exposed
in the gorge, called the Porta Westphalica, by which the Weser
escapes into the plains of Minden, and where all the sub-formations
of the oolitic series, consisting of shales, grits, bands of oolite, &c. are
well exposed. The beds are here considerably inclined, and include
representatives of the English series, from the top of the lias to the
shales of the age of the Oxfordclay. All this system of the inferior and
middle oolite, passes, it is observed, beneath the Biickeburg range of
hills, containing sandstone and calcareous shale with workable seams
of coal, which group the author agrees with M. Hoffmann in refer-
ring to the upper system of the oolitic series, and states that it con-
tains many marine shells ; whilst he distinctly shows that it is not
the green-sand, of which there are clear sections in the immediate
neighbourhood,

Middle Oolite-——Jura Kalk, &¢—The mineralogical characters of
the middle oolite of central and southern Germany are pointed out as
being essentially different from those of rocks of the same age in
Westphalia and Hanover: so that instead of the shales, grits, &c. just
described, they consist in one part of compact, cream.coloured lime-
stone, and in another of dolomite. In Franconia (the great region of
bears’ caves), in the hills opposite Banz, and in many other places, the
dolomite usually caps the limestone, the latter containing the greater
number of the fossils. In these groups and in the inferior oolite,
Count Minster has detected nearly all the species of Ammonites
figured from this part of the series in the Mineral Conchology, with
many other new species ; and has also procured at least sixty species
of Scyphia from the middle Jura kalk, and many other zoophytes now
figured in Goldfiiss,

Solenhofen Slate-—The Jura limestone or middle oolite is observed

within

Geological Society. 49

within a certain limited district, between Kehlheim on the S.E. and
Pappenheim on the N.W., to pass upwards into a slaty, compact
limestone, which is exposed in plateaux overlying dolomitic Jura
kalk on both banks of the river Altmihl, but is of sufficiently
fine texture, in only a few quarries near Solenhofen, to be worked as
lithographic stone*. The quarries are then described, and their
fossil contents, as collected by the author or observed by him in the
collections of Count Miinster and others, are enumerated. Seeing
the prevalence of Pterodactyli, Insects, Crustacee, and Tellinites,
and knowing that these fossils, together with certain plants, are
also found in the Stonesfield slate of England, and further that these
slaty beds at Solenhofen immediately surmount limestones, which
by their contents are found to be the equivalents of the middle and in-
ferior oolites of England on which the Stonesfield slate also rests—he
is led to consider it probable that the Solenhofen and Stonesfield
slates are of similar age; an opinion which he believes has been re-
cently expressed by Dr. Boue.

The whole of this slaty group of Solenhofen, &c. is seen near the
mouth of the Altmiihl to thin out between masses of dolomite ; the
whole being surmounted by green-sand and cretaceous deposits.

The author inclines to the opinion that the higher members of the
oolitic groups of England, viz. Coral Rag, Portland Stone, &c., have
not yet been defined in any part of central Germany, though they
may exist in Hanover ; and he is unable to say whether the limestone
of Nattheim, Heidenheim, &c., so abundant in corals, is referrible to
the upper part of the great oolite or to the coral-rag.

Green Sand.—It is remarked that wherever this formation shows
itself in Germany, it is nearly always divisible, as in England, into
lower or siliceous sandstone, and upper or cretaceous sandstone ;
the former known in certain districts as the guader sandstein, the
latter as the plédner kalk. Numerous sections exhibiting these two
formations are given in various parts of southern Hanover and the
northern flank of the Hartz, where the lower sandstone is sometimes
an highly ferruginous rock, at others a white sandstone, in which
character it ranges from the northern flank of the Hartz into Saxony
and Bohemia. In Westphalia the green-sand series is said to ap-
proach still closer to the mineral type of the English group, and sec-
tions are described near Bidofeld, Soest Weil, &c. in which not only
an upper and a lower green-sand with many characteristic fossils are
described, but also traces of a separating stratum of blue marl or gault.

Chalic.—The author states that the chalk is quite as clearly sepa-
rated from the pliner kalk in Hanover, as the chalk of the South
Downs is from the malm rock or upper green-sand in Western Sussex.
He remarks that on the northern flank of the Hartz, Professor Sedg-
wick and himself observed it to be quite vertical, whilst the under-
lying green-sands were by great faults thrown up into unconformable
juxtaposition; and he further refers to a memoir recently read by
himself, in which the chalk with flints is stated to occur in southern

_* For a specific account of this range, see Von Buch’s Letter to Brong-
miart, 1823,
N.S. Vol. 10. No. 55. July 1831. H Bavaria,

50 Geological Society.

Bavaria, resting in horizontal strata on the granite of the Bohemian
mountains ; and he points out as a necessary inference arising there-
from, that the Hartz and Bohmerwald-Gebirge have been elevated
at distinct periods.

Tertiary Formations—Those peculiar transition-tertiary forma-
tions described by Professor Sedgwick and the author at Gosau, and
in the Austrian Alps, are stated to have been not as yet discovered in
central Germany, but only along certain points encompassing it, such
as at Maestricht, in the Baltic, the Carpathians, and the Alps. The true
tertiary formations, though of considerable extent in different parts of
the country, particularly in Hanover, Westphalia, &c., are stated to
have been hitherto little attended to by native authors. Without en-
deavouring to give anything like a general account of the tertiary de-
posits of Germany, the author rapidly enumerates several localities
where there are great exhibitions of sands, clays, lignite, &c. of the
age of the plastic and London clays, particularly at Hesse Cassel,
and the environs, where the brown coal, &c. of this epoch is traversed,
and in parts prismatized by the overlying basalt (Meisner, &c.). The
lower tertiaries are again spoken of as appearing in many points near
Frankfort. In the environs of Mayence, Wisbaden, &c. it is shown
that they pass upwards into a great estuary deposit of white limestone
and marl, in which fluviatile and land-shells greatly predominate over
those of marine origin, and at Monbach are associated with bones
of large mammalia, so that the author inclines to the belief of the
previous existence of a vast estuary or brackish lake in this spot, the
waters of which have been let off by the fissure through the Taunus
Mountains in which the Rhine now flows.

The low countries of Westphalia, Osnabruch, Briinde, &c. are
specially cited as regions in which a vast development of tertiary ma-
rine strata exists; and little doubt is entertained that when fully
examined they will afford representatives of most of the formations
from the calcaire grossier to the crag inclusive, the latter having
been already discovered at Antwerp, &c.

The deposits of unmixed lacustrine origin in central and southern
Germany, such as Oettingen, Steinheim, &c. are merely named, having
been already alluded to in a memoir upon CEningen, in which the
author endeavoured to prove that deposit to be one of the most recent
on the surface of the earth; and he terminates this communication
with an account of a more newly discovered accumulation of the
same nature at Georges Gemiind near Roth, which, from its organic
remains, is proved to be of an age intermediate between the gypseous
period of the Paris basin, and the youngest lacustrine formations.
Beds of sandy marl, and whitish concretionary limestone are said to
occur in isolated patches, crowning low hills of keiiper sandstone at
heights of about 150 feet above the present drainage of the district,
and containing subordinate layers of calcareous. ferruginous and
bony breccia, in portions of which, collected by the author, Mr. Pent-
land has discovered Palg@otherium magnum; Anoplotherium, new
species, resembling 4. commune, and a new genus allied to Anthraco-
therium or Lopihodon. Mr, Clift has identified fragments of the er

an

Astronomical Society. 51

and bones of the hippopotamus, ox, bear, &c. Count Munster had pre-
viously collected from the same place, remains nearly similar, with the
addition of Pal@otherium Orleani, Mastodon minutum, Rhinoceros pyg-
meus (Miinster), Ursus speleeus, and a small species of fox. Judging
from the appearances on the spot and the evidences there offered of
the gradual accumulation of this deposit, the author is of opinion that
all these animals were of contemporaneous existence, and that this
intermixture of quadrupeds of so old a period as the gypseous lime-
stone of Paris, with others, the genera of which now inhabit our pre-
sent continents, has supplied a valuable link in the chain of fossil
zoological affinities.

The following books are referred to in the memoir: Keferstein,
Teutschland, geognostisch-geologisch dargestelt ; with Maps &c.—
Boué, Synoptische Darstellung.—Boué, Geognostisches Gemialde
von Deutschland, 1829.—Merian, Umgebungen von Basel, 1821.—
Hoffmann, Nord-westlichen-Deutschland ; with Maps, Sections, &c.
Berlin, 1830.—Klipstein, Kupferschiefergebirge der Wetterau und
- des Spessarts, Darmstadt, 1830.—Alberti, Die gebirge des Koni-
greich’s Wurtemberg, 1828.—Schwatzenberg, Petrographische carte
von Kreise, Cassel, 1825.—Von Buch, Letter to Brongniart, Jour-
nal de Physique, Oct. 1822.—Zincken, Ostliche Hartz, Brunswick,
1825.—Hausmann, Uebersicht der jungeren Flétzgebilde im Flusz-
gebiete derWeser, Gottingen, 1824.—Oeyenhausen, Von Dechen und
De La Roche, Geognostische Umrisse der Rheinlander; with Maps,
Sections, &c., Essen, 1825. Together with many memoirs in Leon-
hard’s, Karsten’s and other journals.

ASTRONOMICAL SOCIETY.

April 8.—The following communications were read :—

I. Extract of a letter, dated March 24, 1831, from M. Cauchoix,
of Paris, to the Rev. R. Sheepshanks :—

“| have just finished an object-glass larger than that of Sir J.
South. Two satisfactory trials of it were made on the 17th and 22nd
of March, by Messrs. Bouvard, Arago, Mathieu, and Gambard, on the
trapezium of Orion, Venus, a difficult double star, and Saturn, with
magnifying powers of from 200 to 1000 ; and though the sky was
covered with light whitish clouds, the images were distinct and _bril-
liant, without any colour or scattered light. J subjoin the exact mea-
sures of the object-glass, and the various magnifying powers employed
up to the present time. M. Gambard, who has made more observa-
tions with this telescope than any other person, thinks that stronger
eye-glasses may be easily adapted to it.

Old French feet. | Metres. |English feet.

| ———

i al fi i.
Diameter of the convex lens........ 5 Lge ed! bE 0°354 1 1°86
———_- --—. concave flint-glass to 70 0°34] 1 1:50
— real aperture...... 1 OF 25 0°335 YrPeyg
Focus of the object-glass............| 23 7°b0 7700 | 25 3:00
Powers employed.,..... 201, 324, 397, 461, 786, and 1000.
H 2 « These

52 Astronomical Society.

««These powers are not exaggerated, but have been measured.with
scrupulous care ; so that you may be assured no future trial will give
them less than the numbers here quoted.”’

II. A communication from the Astronomer Royal, containing the
results of all the observations, which have been made at the Royal
Observatory at Greenwich, of the sun’s zenith distance, at or near
the solstices, from the time of Bradley to the present time.

Mr. Pond states the latitude of the Royal Observatory, which re-
sults from Bradley’s observations, to be 51° 28! 40,323 ; and that
which is obtained from his own observations to be 51° 28! 38",077 ;
the difference being 2',256.

II]. A communication from Sir Thomas Brisbane, consisting of ob-
servations of the moon, and moon-culminating stars, during the years
1829 and 1830, made at Makerstoun witha four-feet transit. Sir
Thomas Brisbane states in the letter accompanying his paper, that
«the observations were almost entirely made by Mr. Dunlop.” The
paper contains the observed differences in AX between the moon
and the moon-culminating stars, observed before and after her culmi-
nation, and also the number of wires used in each observation.

IV. On the theory of the eye-glasses of telescopes ; by Professor
Littrow, Associate of the Society.

V. The reading of a paper by Francis Baily, Esq., ‘On Lacaille’s
Catalogue of 398 principal Stars,” was begun.

May 13.—The following communications were read :—

I. Mr. Baily’s paper, “On Lacaille’s Catalogue of 398 principal
Stars,” was concluded.

In this paper Mr. Baily has entered into the merits of this cele-
brated catalogue. The method adopted by Lacaille for determining the
right ascensions was that known by the name of equal altitudes: for
when he commenced his astronomical career, the transit instrument
was but little known, and not fully appreciated ; and although it had
been introduced into the observatory by Roémer, yet it was soon
abandoned for the mural quadrant, which at that time was consi-
dered a more manageable and accurate instrument, and capable of
giving at one view both the right ascensions and the declinations.
The instrument used for this purpose was a 3-feet quadrant : and he
usually took about 14 or 16 altitudes on each side of the meridian.
The culmination of the stars being thus determined, he compared
them with a Lyre or Sirius (whose absolute right ascension had been
ascertained by frequent comparisons with the sun), and thus computed
their right ascensions relatively to those stars. The declinations were
determined with two different instruments: one a 6-feet sector, and
the other a 6-feet sextant; the divisions of which were examined
with great care by himself, and the trifling discrepancies noted and
allowed for.

By the help of these instruments, Lacaille determined the positions
of nearly 400 of the principal stars in the northern and southern he-
misphere: and the catalogue which he thus produced, and which is
the subject of the present memoir, is worthy of being placed in com-
petition with those of his distinguished contemporaries, Mr. or

as

Astronomical Society. 53

has examined this catalogue with great care, and has discovered a
few errors, which seem to have escaped the diligence of its illustrious
author.

When Lacaille had finished his observations and his catalogue, he
was at aloss for the means of publishing them ; since his own limited
income would not warrant the expense. He tried several modes of
doing this, and at last agreed with his bookseller to compute for him
an astronomical ephemeris for ten years, if he would printa sufficient
number of copies for distribution amongst his scientific friends and
correspondents. Such was the origin and cause of the Fundamenta
Astronomie,—a work which was not published for sale, and which
can therefore only be obtained accidentally from time to time as it
occasionally passes from the hands of those to whom it was originally
presented. It is consequently very rare ; and those who possess it
ought (as M. Delambre emphatically expresses it) to preserve it as a
precious relic.

As the catalogue has never yet been reprinted, in the extended and
perfect form in which it exists in that work, Mr. Baily conceived that
he should be rendering an acceptable service to astronomers in pre-
senting it to them, thus corrected, through the medium of this So-
ciety, accompanied with a comparison of the places of all the stars
visible in this latitude, with those given by Bradley; and a reference
to every observation of every star; together with notes accompany-
ing the whole. Mr. Baily has also mentioned another motive which
induced him to examine the comparative merits of this catalogue at
the present time: since above one-third of the stars are so situated
that they cannot be observed in this latitude, on,account of their great
southern declination. These stars, therefore, he justly remarks, will
afford a favourable opportunity of comparison with the same stars as
observed by Sir Thomas Brisbane at his observatory at Paramatta ;
whose valuable and extensive observations are now in the course of
reduction at the public expense ; and thus enable us to determine,
with considerable precision, the annual variation of at least 136 prin-
cipal stars in the southern hemisphere. Mr. Baily closes his paper
with a few remarks on the scientific life of Lacaille.

Il. A letter from Mr. Dawes, dated April 23, 1831, of which the
following are extracts :—

«T beg to call the attention of the Astronomical Society to an in-
teresting circumstance respecting the triple star ¢ Cancri. [ am not
aware of any published observations relative to the positions of the
stars composing it, since those of Sir James South, made at Passy
in 1825. Possibly, however, such may exist, and may render my pre-
sent communication unnecessary, or, at any rate, less interesting.

“The evenings of the 19th and 20th of this month proving favour-
able for delicate observations, | directed a five-feet achromatic tele-
scope to this object. This instrument was constructed for me last
year by Mr. Dollond ; and from the perfectly round, clean, and very
small discs with which it exhibits the fixed stars, it is peculiarly
adapted for the examination of very close and delicate objects. It is
mounted equatorially, with horary and declination circles, each of ib

ect

54 Astronomical Society.

feet diameter, and is furnished with a position and _parallel-thread
micrometer, possessing a variety of magnifying powers, from 55 to
625. ‘The instrument was fitted up with a special view to the exami-
nation of the positions and distances of the multiple stars. Each part
of the micrometer screw-heads is equal to 0',5559219.”

Mean result, Pos. of AB = 59° 13! nf (16 obs.) Dist. = 1,095 (7 obs.)
Pos. of AC = 60 17 sf( 5 obs.) Dist. = 5 ,592 (5 obs.)

After giving the observations, Mr. Dawes proceeds thus :—

“«‘ Now, if we compare these results with the measurements of Sir
W. Herschel in 1781, and of Sir James South in 1825, a very extra-
ordinary variation appears. In 1781-90, Sir W. Herschel’s measure
of the position of AB was 86° 32! nf. In 1825°27, a mean of 43
measures (the means of the six different sets on as many nights,
agreeing admirably together) gave as the position 32° 10! nf, offering
a difference of 54° 22’ from the position in 1781. Now, however,
the angle lies as nearly as possible midway between the two, being
27° 19! less than that of 1781, and 27° 3! greater than that of 1825;
while the distance, as measured by me, is only 0,009 greater than
the result of 15 observations by Sir J. South. It would therefore,
appear as if the motion had been performed in a direct sense (or nf sp)
for perhaps thirty or forty years; and that the star B had then come
to a stand, (or appeared to do so), faced about, and is now proceed-
ing in the opposite direction, which is the same pursued by the star
C. But this is an extravagant idea; and unless there exist obser-
vations in the intervening period to invalidate the supposition, I think
we may arrive at a solution of the difficulty in a more simple manner;
namely, that in the forty-nine years elapsed since Sir W. Herschel’s
measurement, the star B has performed almost an entire revolution, in
a retrograde sense, or np sf, only about 27° or 28° being wanting to
complete it.

“Mr. Herschel, in his notes appended to Sir J. South’s valuable
paper, forming the first part of the Philosophical Transactions for
1826, has mentioned an observation of this star by his father in 1802,
“at which time,’ it is said, ‘no measures cuuld be procured.’ Now,
supposing this to be the only observation recorded during the inter-
val, it may be asked, Would not Sir W. Herschel have been struck
with any remarkable alteration in the relative positions of A and B,
even supposing the circumstances were not such as to admit of mea-
surements? To this it may be replied, that it is highly probable the
star B would, about the year 1802, have arrived at that point of its
orbit in which it would be nearly opposite to its place in 1781; and
the stars differing but little in size, it might not be noticed, especially
in unfavourable circumstances, which preceded ; and, consequently, it
might easily be imagined to have sustained but little, if any, alteration.

“‘ The position of B now observed is the more remarkable, because,
had it pursued the course formerly assigned, its angle relative to A
would now be about 24° or 25° nf. That an error of 35°, or any
thing like it, should be committed in my measurements, appears quite
improbable ; since, if we examine them, we shall find that the extreme
difference of all the sixteen measures taken on the two evenings is

only

Zoological Society. 55

only 3° 35’. And I may here observe, that in measuring both posi-
tions and distances, I always derange the former measurement so
completely, that the situation of the wire could not by possibility be
taken fora measure. Thus, each individual measure is not a previous
one, altered and amended, but is entirely new and independent,

“It will be seen that the above observations corroborate the pre-
sumed motion of tne star C in direction, and indicate a considerable
acceleration in it since 1825, compared with the mean velocity during
the previous forty-two years; while the distance continues very nearly
the same as it was at that date. Compared with Sir J. South’s ob-
servations, the change of angle amounts to 7° 38! in six years, or
1°,267 per annum ; while, previously, the mean motion was supposed
to be only 0°,5813. Butin the observations appended to the mea-
sures by Messrs. Herschel and South, in 1822, we were forewarned
to expect an acceleration, if the motion were orbitual. My observa-
tions of the star C, however, being made on one night only, may be
liable to an error of one or two degrees, especially as the position of
the star B, and its extreme proximity to A, render the measures of C
difficult.”

III. An Index to the Society's Catalogue, by Lieut. W. S. Strat-
ford, R.N.; so arranged that the number of any star contained in the
Catalogue may be found immediately, provided there be given the
name of the constellation, and the letter by which the star is distin-
guished, or the number of the star in one of the following catalogues;
viz. Flamsteed’s, Piazzi’s, Bradley’s, Lacaille’s, Fallows’s, Zach’s, &c.,
preference being given to each catalogue in the order of succession.

1V. A paper containing micrometrical measurements of 364 double
stars, by J. F. W. Herschel, Esq.

ZOOLOGICAL SOCIETY.
April 26, 1831. Joshua Brookes, Esq. in the Chair.

Mr. Vigors exhibited, from the collection of Mr. Leadbeater, an
undescribed species of Cockatoo from New Holland, and pointed
out its distinctive characters, which may be expressed as follows :

Prycrotornus Leapseateri. Plyct. albus; genis, collo in

Jronte, pectore, tectricibus alarum inferioribus, abdomineque
medio roseo-tinctis ; criste elongate occipitalis plumis basi roseis,
apice albis, macula flava in medio notatis; pogontis remigum
rectricumque internis roseis, illorum saturatioribus.

Statura Plyct. sulphurei, Vieill.

Eleven species of Chetodons, forming part of the collection of
Fishes from the Mauritius presented by Mr. Telfair, were laid on
the table. Seven of these were referable to the genus Chetodon as
restricted by M. Cuvier; and among them Mr. Bennett pointed out
more particularly the Chet. strigangulus, Sol.; the Chet. vittatus,
Schn.; the Chet. Lunula, Cuv. & Val.; and two species which he
believed to be new to science, and which may be thus characterized :

Cut, FLAVEScENS, Chat. flavus; ore, fascia oculari, lined

pinnas dorsalem analemque posticé ambiente, apiceque pinnarum

ventralium

56 Zoological Society.

ventralium nigris ; lateribus argenteo vittatim guttulatis ; pinna
caudali recta, apice laté hyalino.

Ds sews 53,,)&c-

Affinis, ut videtur, Chet. virescenti, Cuv. & Val. Differt colore
flavo; pinnis verticalibus posticé nigro tenuiter cinctis ; lateribus
obscuré argenteo-guttulatis.

Cut. Zoster. Chet. brunneo-niger ; zona lata medid ventreque

argenteis ; pinnd caudali recté albd: fascia oculari nulla.
yas vas atrlnlPs D7. sian es

The remaining species exhibited types of the genera Heniochus,
Cuv.; Zanclus, Cuv. & Val.; Holacanthus, Lacép.; and Plataz,
Cuv.: the Heniochus being the species recently described by
MM. Cuvier and Valenciennes as the Hen. monoceros. In this
individual the spine in front of each orbit is strong, almost equalling
the single spine which projects from the middle of the slope of the
head; and the whole contour of the anterior part of the fish ap-
proaches very nearly to that of Taurichthys, Cuv. & Val.

Mr. Gray exhibited several living specimens of the Rana Ru-
beta, L., the Natter-jack of Pennant, a reptile intermediate in form
and habits among the British Amphibia between the Toad and the
Frog. He stated that this animal, the indigenous existence of
which has frequently been doubted, is found abundantly on Black-
heath, and on other commons in the neighbourhood of London.

Mr. Gray also exhibited several specimens of the genus Rhyn-
chea, Cuv., and pointed out from among them two distinct species,
which may be thus characterized :

Ruyncnza Carensis, Sav. Rhynch. remigibus angustis, fascits

latis flavis sex notatis, infra griseis, nigro-vermiculatis, flavoque
JSasciatis ; secundariarum macula pogoni externi, fascidque po-
gonit interni, flavis.
Long. a ae 93 unc.: tarsi, 214 lin.: digiti unguisque medii,
205 in.

Ruyncu#a picta. Rhynch. remigibus sublatis, externis flavo
late 7-fasciatis, infra griseo nigroque vermiculatis, interno obso-
leté flavo-fasciato: secundariarum apicibus, maculd ultima fascie-
JSormi pogonit externi, fascidque pogonii interni, albis.

Long. corporis 104 unc. : tarsi, 194 lin.: digiti medii, 19 lin.

The wing-coverts of both species are spotted with yellow in the
young state; and in the adult state are metallic olive with black
bands.

Mr. Gray added that the three figures of birds of this genus which
were published by Buffon, and which had of late years been re-
garded by M. Temminck and by M. Cuvier as representing various
states of but one species, were none of them sufficiently correct in
the details to enable him to refer either of the present species to the
representations given in the ‘ Planches Enluminées; but that the
figure of the Rhynchea Capensis given by Savigny in the ‘ Oiseaux
d’Egypte’ [tab. 14. fig. 2.|, furnished a faithful representation of
the first species exhibited by him. He had not, however, obtained
this bird from the Cape of Good Hope, his specimens being from

India

Zoological Society. 57

India and China. The second species, Rhynchea picta, he had re-
ceived from Africa as well as from India and China.

Mr. Vigors called the attention of the Committee to the Frigate-
bird ( Tachypetes Aquilus, Vieill.), and dwelt upon those peculiarities
of its organization which point out its station in the series of na-
tural affinities that connect the orders of birds. Although it possesses
the webbed feet which constitute the technical character of the Na-
tatorial Order, the weakness of its legs and their complete covering
of feathers preclude it from employing these members in the same
manner as the typical groups of the Swimming Birds ; while on the
other han its great powers of wing and tail adapt it for powerful
and long-continued flight, and evidently connect it with the Rap-
torial Order, which it also resembles in its manner of taking its
food. It is in fact rather an inhabitant of the air than of the water;
and it has been believed that it derives support during its unlimited
flights not merely from the strength and expaasion of its wings and
the singular mechanism of its tail, but also from the buoyant nature
of the inflated sac beneath its throat. A proof of the correctness of
the opinion that this pouch is really an air-sac, and that it is filled
with air, which passing through the bones becomes rarified and ca-
pable of imparting a high degree of buoyancy, has recently been
obtained from the anatomical notes made by Mr. Collie, late Sur-
geon of H.M.S. Blossom, who accompanied Captain Beechey in
his voyage to Behring’s Straits; notes which will shortly be pub-
lished in illastration of the natural history of that expedition. “The
pouch beneath the throat of this bird,” says Mr. Collie, ‘is of a
yellowish red colour, and when distended, the feathers on its upper
and posterior surface are separated to some distance from each
other, and exhibit very distinctly the quincuncial order in which
they are implanted. On first looking at this pouch, I was a little
surprised at finding that it did not communicate with the mouth or

Jauces in any way that I! could perceive. I succeeded in inflating
it only by long and forcibly blowing into the trachea. I desired the
man who had the skinning of the specimens brought on board to
inflate the pouch before commencing the skinning, and to let me
know when he had advanced to the shoulders. He however dis-
located the shoulder-joint first, when the distended pouch imme-
diately collapsed. ‘The trachea had been tied. As soon as I was
informed of this, I had little doubt that the pouch had been in-
flated from the lungs; and on observing two wide openings, one
anterior to the humeral articulating face of the scapula, the other
the usual opening of the joint, I hesitated not to infer that it was
through the first of these the air had passed in, and that the dislo-
cating of the joint, by which its capsular ligament was torn, had
allowed the air to escape at the opening which corresponds to that
on the head of the humerus, and which immediately leads, as well
ax the other just mentioned, into the centre of the scapula. I now
opened the trachea immediately before the sternum, and again
attempted inflation from that part, but in vain. 1 tried it also, but
with no better success, from the larynx. 1 next examined with the

N.S. Vol. 10. No. 55. July 1831. ] blowpipe

58 Zoological Society.

blowpipe near the opening of the scapula, in the cellular substance
under the skin, and soon detected a small opening that conducted
the air to the pouch, which was readily inflated by blowing through
the opening, and so long as it was shut the pouch continued dis-
tended. That this opening was not artificial,—the effect of the
rupture of the fine membrane lining the air-bladder,—was evident
from its not opening directly into it, but only after a passage of
some length, gradually enlarging. That this was the sole opening
into the pouch appears proved from the fact that after detaching
the sac from all the parts beneath, 2. e. from all the parts excepting
the skin, it did not permit the gas to escape except by this open-
ing, and that it continued to be capable of inflation from it. I was
satisfied in discovering it on one side ; and of course inferred that it
was similar on the other, the opening of the scapula being similar.”

At the request of the Chairman, Mr. Martin read the following
notes of the dissection ofa female Testudo Greca, Linn., which died
in the possession of Oct. Morgan, Esq. The animal was of the
usual size, its dimensions being as follows: the carapace in length
13 inches ; the plastron 94 inches in length; and the circumference
of the shell, 18 inches.

«‘ The plastron being removed, the viscus which first attracted
notice was the liver, of large dimensions, stretching across from side
to side, and quite covering the stomach. Its structure was very
firm, and its colour a dull ochre. It consisted of two lobes, both
deeply fissured. In the cleft of the right lobe was situated the gall-
bladder, of the size of a large nut, and containing green bile. The
cystic and hepatic ducts united, and entered the duodenum 13 inch
below the pylorus.

‘«« On the liver being turned aside, the stomach presented itself; its
coats were firm and thick, especially in the pyloric portion, which
was produced long and narrow to the extent of 33 inches; the
total length of the stomach was 63 inches.

« The small intestines, remarkable also for their firmness, mea-
sured 2 feet 8 inches in length, and terminated in large intestines
very little exceeding them in circumference. In the Testudo In-
dica lately dissected, there was no cecum; but in the present
species the cecum existed ; its form was globular. On the left side
the large intestine assumed a sigmoid flexure with a bold sweeping
fold, and then took on a straight and short course to the cloaca ;
the length of the large intestines was 1 foot 8 inches. They con-
tained feculent matter in small quantity, consisting of fibrous vege-
table substance. There were no longitudinal bands.

“The cloaca, into which opened the bladder and oviducts, was
in length 2 or 3 inches. The bladder in the present instance
did not exhibit that immense volume which was so remarkable in
the Test. Indica: it was of amoderate size ; both in this respect and
in figure resembling a pear. It was united to the sides of the upper
shell by a broad peritoneal ligament, and was connected also to the
pelvis by several fibrous bands. Its coats were extremely thin and
fibrous; and it contained a small quantity of thick fluid.

The

Zoological Society. 59

« The oviducts were before their opening into the cloaca united
for a considerable distance, and were there thick and firm, becoming
gradually thinner as they proceeded upwards, their course being in
an indefinite convoluted manner. Throughout the greatest part of
their length there ran a number of longitudinal folds, which became
fainter, and were at length obliterated as the oviducts proceeded.

« The ovaries contained a multitude of eggs of various sizes, and
of a round figure ; fifty of them at least were nearly as large as a
pigeon’s egg: they were not covered with a shell, and were filled
with a thick yellow yelk.

« The kidneys laid upon the lungs (which extended over the
carapace), to which they adhered ; their figure was somewhat 3-sided,
from a broad flat base, with a rounded apex : their length was 25
inches. ‘Their surface was convoluted in a very singular manner,
the folds being divisible, producing an appearance not unlike that
of the cerebellum, which they also resembled in colour.

“ On the mesocolon and near the intestine was situated an oval
glandular body of a dark colour, and of the size of a sparrow’s egg,
containing white gritty specks. From this, which I suspected to
be the spleen, a large vein proceeded along the mesentery, and uni-
ting with several others, entered the liver ; all the veins proceeding
from the viscera along the mesentery were very large and full of
dark blood.

« The tongue was thick and fleshy, about an inch in length and
two-thirds in breadth, white in colour, and covered thickly with
elongated papilla ; the tip was rounded, the base heart-shaped.
Between the glottis and base of the tongue so slight a distance in-
tervened, that the larynx might be said to open directly into the
mouth, the glottis rising to a point corresponding with and adjusted
to the heart-shaped indentation at the base of the tongue. This
elevated apex is divided downwards and a little way longitudinally
by the rima. The larynx is supported posteriorly by the os hyoides,
which is broad, flat, and pointed with double barbs, resembling
some double-barbed arrow-heads : it is however composed of three
bones, viz. a body, and two long curved bones united by cartilages
to it, the body itself ending in two long cartilaginous processes ;
where the osseous processes arise there is also on each side a small
cartilaginous projection. An inch below the rima the trachea divides
into two branches, or bronchi, which run down for a little way, on
each side of the neck, but shortly, in consequence of the bend of the
neck, almost at the back of it, and describing in their course a large
sigmoid inflexion, they then subdivide and immediately enter the
lungs. About half an inch below the great division a strong muscle
of two or threc lines in breadth passes across, arising from the ver-
tebre of the neck on one side and united to the same on the oppo-
site, thus acting as a constrictor on the two tubes, and being doubt-
less of use in the deglutition of air. The length of the trachea and
the great branches to the lungs was 74 inches ; the rings were per-
fect. The subdivisions of the bronchi before entering the lungs are
surrounded closely by numerous yellow glands.”

I 2 May

60 Zoological Society.

May 10,1831. W. Yarrell, Esq. in the Chair.

A letter, addressed by Richard Thursfield, Esq. to Dr. Roots,
was read, in illustration of the history of a hybrid between the Hare
and the Rabd:t, which was lately living at the Society’s Farm. A
gentleman who was rearing a pair of tame rabbits, placed with them,
when they were about two months old, a young buck hare appa-
rently about the same age, which became in a short time as domes-
ticated as its companions. When the doe rabbit was old enough,
she had, by the buck rabbit and the hare, a litter, consisting of three
young ones, which resembled in all respects the mother and buck
rabbit, and of three mules. Two of these mules shortly died: the
third, a female, was reared with rabbits of her own age, and when
six months old produced one young one: she was afterwards bred
from eight times, by tame rabbits and by a wild one, but no oppor-
tunity occurred of placing a buck hare in confinement with her.
Her progeny by a white tame rabbit, with which she bred twice,
consisted of two young ones, which were perfectly gray, and of
two which were spotted: the latter are still alive, and breed regu-
larly, producing from five to eight at atime. The average weight
of the progeny of the mule female was about five pounds ; one,
however, weighed six pounds and a half. She died shortly after
coming into the Society’s possession.

Mr. Owen, having examined the body of this hybrid animal after
its death, reported that its size and colour were those of the Hare,
but that its hinder legs were shorter than in that species, and agreed
rather with those of the Rabd:t. The length of its small intestines
corresponded with that of the hare; its cecum was seven inches
shorter ; while its large intestines measured one foot more than
those of the hare.

Mr. Bennett called the attention of the Committee to the speci-
men of the Sociable Vulture ( Vultur auricularis, Daud.), which has
been an inhabitant of the Society’s Gardens for nearly two years.
His object in adverting to this bird was to correct an erroneous im-
pression which might be produced on the minds of those who had
never seen an individual of the species, by the statement made by
M. Ruppel, in a late Monograph of the genus to which it belongs,
that considerable doubts as to the existence of such a species might
reasonably be entertained. M. Ruppel’s doubts appear to have been
excited by the fact which he reports, that the stuffed skin in the
collection of the Duc de Rivoli at Paris, which has been regarded
as that of the Vult. auricularis, is evidently factitious ; the folds of
the skin on the head and neck having been produced in that speci-
men by artificial means. These doubts must, however, be at once
dissipated by the existence of a living specimen brought from the
Cape of Good Hope, according in every particular with Le Vail-
lant’s description of the Oricou, and having the remarkable folds of
skin which pass up the sides of the neck and round the ears developed
even to agreater extent than is represented in his figure. A specimen
of the Pondichery Vulture ( Vultur Ponticertanus, Daud.), the eed

other

Zoological Society. 61

other species in which the naked neck has on each side a longitudi-
nal fold of skin, was laid on the table: and it was pointed out that
in this bird the fold of skin terminates an inch below the opening
of the ear, while in the Sociable Vulture it passes upwards and sur-
rounds the upper part of the ear; and that the breast-feathers of
the Pondichery Vulture are short and rounded, while those of the
Sociable Vulture are very long and somewhat sabre-shaped.

Mr. Gray stated, that since M. Ruppel’s Monograph was written,
he had apprised that scientific traveller, in answer to his previous
inquiries on the subject, that a specimen of another vulture rejected
by him as a doubtful species (the Vultur Angolensis, Lath.) exists
in the British Museum, to which it was presented on the return of
the unfortunate expedition up the river Congo.

Mr. Owen resumed the reading of his Memoir on the Anatomy of
the Orang Utan (Simia Satyrus, L.), portions of which had been
communicated by him to the Committee at several of its previous
Meetings. On this occasion he limited himself to the myology of
the lower extremities.

He commenced by remarking, that no anatomist can contemplate
the lower extremity of a Quadrumanous animal, or experience the
degree of mobility of which the several parts of it are susceptible in
the living or undissected body, without being prepared to find cor-
responding modifications of the muscular system and consequent de-
viations from the structure of these parts as they exist in man. It is
accordingly in this part of the body that the most remarkable diffe-
rences in the forms, proportions, and attachments of the muscles are
found to obtain between the ape and the human subject; and it will
not therefore be matter of surprise to find, that in the Orang Utan,
whose inferior extremities, from their shortness and flexibility, are
so well adapted to the various agile movements of a climber, there
exists a high degree of this deviation from the human structure,
and an approximation, in some measure symmetrical, to the arrange-
ment of the moving powers in the upper extremity. Variations of
more or less consequence occur, indeed, so frequently as to render
it necessary to consider the whole of the muscles serviatim; and
each of them was accordingly described separately as regarded
its attachments, form, and relative position. These details are
necessarily abridged in the present abstract, except as regards
the muscles of the hinder hands, which require a developed notice
to render their structure intelligible.

The gluteus magnus is a thin narrow muscle, inserted lower down
the thigh bone, and having a more posterior origin than in man :
its extent of action is consequently increased, though its strength
is diminished. The gluteus medius is also relatively longer than in
man, and is four times as thick as the preceding muscle. The glu-
te@us minor is narrow, long, and thin. The pyriformis is narrower
than in man. The tendon of the obturator internus passes as usual
between the gemini, of which the inferior is much the largest. The
obturator externus is considerably larger than the internus. The
quadratus femoris has very little of the square in its shape, being

much

62 Zoological Society.

much longer than it is broad, and becoming narrow and rounded at
its insertion.

The biceps cruris consists of two portions, each maintaining a
distinct course and having a distinct insertion: one of these may
be termed ischio-fibularis, and is inserted into the head of the f-
bula; the other may be termed femoro-fibularis ; its insertion is
into the outer edge of the fibula from the head to the middle of the
bone, and into the fuscia in front of the leg. The semztendinosus
and semimembranosus have the same origins as in the human sub-
ject, and the latter muscle a similar insertion; but the semitendino-
sus separates from it at the lower part of the thigh, and continues
fleshy for some distance below the knee-joint ; after which the ten-
don expands into a broad strong aponeurosis, which is attached along
the anterior and inner aspect of the ¢ébza to within a short distance
of its lower extremity. In its insertion, the semilendinosus of the
Chimpanzee approaches more nearly to the human type, being im-
planted by a narrower tendon in front of the ¢2bia immediately be-
neath the insertion of the gracilis; but both these muscles are
inserted lower down than in man.

Mr. Owen remarked, that the names of these last-mentioned
muscles by no means agree with the proportion of tendon found in
them either in the Orang or the Chimpanzee, the fleshy portion
being in these animals of much greater extent ;—a fact which is in
accordance with a law that receives many illustrations from the
myology of the Orang Utan, viz. that the extent of the fleshy part
of a muscle is in proportion to the quantity of motion it has to
produce: and this is generally indicated by the degree of motion
allowed by the structure of the joint which is the centre of the mo-
tion in question. Thus in the human subject it is very rare that an
individual can, by the contraction of the flexors of the leg, bring
the heel in contact with the back of the thigh; but in the Orang
Utan this action is readily performed, and without the slightest op-
position at the knee-joint.

The tensor vagine femoris exists distinctly in the Chimpanzee, but
no trace of it was found in the Orang. A more powerful rotator of
the thigh inwards exists in both animals in a peculiar muscle, which
may be termed invertor femoris. It was first discovered by Dr.
Traill in the Chimpanzee ; and its origin, form, and insertion in that
animal agree with those which are met with in the Orang Utan.
Mr. Owen considers that from its insertion into the under and outer
part of the trochanter major, and consequently very near to the
centre of motion, it can have little effect in drawing the thigh up
towards the body as compared with the power of the proper flexors
of the thigh. It appears rather to have reference to that structure
of the hip-joint which, in the Orang especially, from the absence of
the ligamentum teres, and in the Chimpanzee, from the yielding tex-
ture of that ligament, permits a greater extent of inward rotation
than can be accomplished in man.

The sartorius is inserted lower down than in man. The rectus
cruris corresponds with the same muscle in the human subject ; but

the

Zoological Society. 63

the vasti and crureus are much weaker and thinner, and are evi-
dently little adapted to support the thigh and trunk upon the #2bia.

The psoas magnus and iliacus internus are, on account of the form
of the pelvis, proportionally longer muscles than in man. Beneath
them exists a small distinct muscle passing from the fore part of the
ilium, over and attached to the capsule of the hip-joint, to be inserted
into the root of the trochanter minor. This muscle is not found in the
Chimpanzee. The pectineus is a narrower muscle than in man, and
gives off, in the Chimpanzee, a small slip, which is continued under
the femoral vessels and outwards to the origin of the sartorius. The
gracilis is a very powerful muscle in the Orang, but is comparatively
of less bulk in the Chimpanzee, in which it is inserted beneath the
sartorius. On this muscle being removed, a number of others appear
passing from the pelvis to the inner part of the thigh, among which
it is difficult to select those which are precisely analogous to the
muscles in the corresponding region of the human subject. Mr.
Owen, however, distinguished the adductor longus ; an accessory
adductor avising trom the upper part of the symphysis pubis ; the
adductor brevis ; and the adductor magnus.

The gastrocnemius preserves nearly a uniform thickness and
breadth throughout its course, and is continued fleshy down to the
os calcis: it has no sesamoid bone, as possessed by some monkeys
(e. g- Macacus cynomolgus, Lacép.), at either of its origins. The
soleus has only one origin, and is continued fleshy to the os calcis.
The tendon of the popliteus contains, behind the knee-joint, a fibro-
cartilaginous sesamoid body, which was noticed by Camper, who
states that it exists also in baboons, dogs, cats, &c.: this body, how-
ever, is not found in the Chimpanzee.

In the Orang Utan there are some important differences in the
disposition of the flexors of the toes, as compared with the Chim-
panzee and inferior Simie ; thus the muscle analogous to the flexor
longus pollicis pedis sends no tendon whatever to the thumb of the
foot, and its origin is extended above the knee-joint in a manner
analogous to the flecor sublimis in the upper extremity. It has two
origins, one from the outer condyle in common with the gastro-
cnemius internus, the other from the head of the fibula, and is con-
tinued down the posterior part of that bone and the interosseous
ligament to within an inch of the tarsus; under which it passes
through a broad synovial sheath, deeper seated than, and external to,
the flexor longus digitorum ; becoming tendinous centrad, but con-
tinuing fleshy on the dermal aspect till it has reached the sole.
There it divides into two stout perforating tendons, which are in-
serted into the distal phalanges of the third and fourth toes. Im-
mediately after the division each tendon gives origin to a lumbri-
calis muscle, which terminates in a thin aponewrosis attached along
the tibial side of the proximal phalanges of the third and fourth toes.

The flexor longus digitorum pedis arises as in the human subject,
but continues fleshy till it has passed under the abductor pollicis ;
it then gives origin to a /umbricalis muscle, and divides into three
tendons. The CD aitcalis terminates in the middle tendon of the

three.

64 Loological Society.

three. The innermost or first tendon goes to the distal phalanx of
the second toe; it also gives rise to a /umbricalis, which is inserted
into the tibial side of the proximal phalanx of the same toe. The
second tendon, after receiving the insertion of the dumdricalis before
mentioned, goes to form the perforated tendon of the fourth toe.
The third or outer tendon is inserted into the distal phalanz of the
fifth toe, and also gives origin to a dumdricalis, which terminates in
the tibial side of the proximal phalanx of the same toe.

The flexor brevis digitorum pedis arises from the posterior part of
the os calcis, its fibres passing transversely over the insertion of the
tendo Achillis. At about two inches from its origin it gives off a small
tendon, which is inserted into the second phalanz of the second toe.
It then continues fleshy for an inch further, and terminates in the
perforated tendon of the third toe.

Thus all the toes from the second outwards, have a flexor tendon
inserted into the distal phalanx: they have also alumbricalis tendon
attached to the proximal phalanz, and the second, third, and fourth
have tendons inserted into the middle phalanx. As each perforating
tendon gives origin to the dumbricalts muscle of its respective fin-
ger, these not only assist in the flexion, but act as guys on the
tendons, from which they originate, preventing them from starting
from the long concavity of the sole over which they travel: they
also afford a variety of independent motions to the fingers. The
tibialis posticus has the usual origin; its tendon passes along a dis-
tinct sheath close by the internal madleolus ; it is inserted into the os
cuneiforme internum, The tendon has no sesamoid bone where it
passes over the astragalus. In the Chimpanzee it is inserted into the
os naviculare.

The muscles in front of the leg are covered with a strong fascia,
into which the tendons of the semitendinosus and biceps are inserted;
it affords origins for the muscles situated beneath it, and becomes
very strong at the ankle, binding down and forming sheaths for
the several tendons. The ¢zbialis anticus arises from the anterior
inner and posterior aspects of the ¢ibza, embracing it, as it were, and
giving the appearance of a rickety convexity to the leg; it passes
over the malleolus internus posterior to the centre of motion, and is
consequently an extensor of the foot; it also turns the sole inwards,
In close connection with this arises another muscle, not found in
man; it becomes tendinous about three-fourths down the leg, and
is inserted into the base of the metatarsal bone of the thumb, which
it extends: this muscle is found in the Chimpanzee, and also, ac-
cording to M. Cuvier, in the inferior Simze@. The extensor longus
pollicis makes its appearance as usual between the tzbza/ts anticus and
extensor longus digitorum ; it is inserted into the base of the phalana:
(the female specimen that was dissected had only one phalanz to the
hinder thumb), The digitorum tensor longus has the usual origin,
continues fleshy to the ankle-joint, there divides into three tendons,
which diverge at the middle of the foot, and are attached to the
third, fourth and fifth toes; each tendon expanding into a sheath
over the back part of the phalanges. ae

he

Soological Society. 65

The extensor brevis digitorum pedis arises from the os calcis, and
divides into three portions; the strongest of which gives two ten-
dons to the second toe, one being inserted at the base of the proximal
phalanx, the other expanding over the second and distal phalanges
like the tendons of the extensor longus. The remaining portions go
to the fibular aspect of the third and fourth toes.

The peroneus longus and brevis arise together from the outer, fore,
and back part of the fibula ; on the latter aspect they are in con-
nection with the flezor longus pollicis. The tendon of the peroneus
brevis is inserted into the base of the metatarsal bone of the little
toe. The tendon of the peroneus longus passes under the cuboid
bone, without the interposition of a sesamoid bone, crosses the foot,
and is implanted into the metatarsal bone of the thumb of the
hinder hand, of which, as far as the structure of the articulation
will permit, it isa flexor. There is no peroneus tertius.

The thumb is very short, consisting, in the female at least,
of only two bones, set on at right angles to the foot, and at a
great distance from the toes, In this part, however, the power of
a considerable muscular apparatus is concentrated. Receiving no
tendon from the flexor longus pollicis, it is rendered more inde-
pendent in its actions; not being necessarily flexed, except in the
action which turns down that side of the foot to which it is attached,
and by which it is brought closer to the object to be seized. On
the sole of the foot we find an abductor and an adductor pollicis, both
powerful muscles inserted at very open angles into the phalanz ;
which, when they cooperate in their contraction, they must draw
down in the diagonal with great force. Between these are situated
two more direct flexors, constituting what is usually termed the
flexor brevis pollicis.

The space between these muscles, which in man and the Chim-
panzee is filled by the tendon of the flexor longus pollicis, in the
Orang Utan is occupied by a small peculiar muscle which arises
from the metatarsal bone, and is inserted into the phalanx. Ina
young male Orang that had two phalanges the flexor brevis was
inserted partly into the second phalanx. The extensor brevis pol-
licis arises from the os naviculare and os calcis, and is inserted into
the base of the proximal phalanx, when there are two.

On the dorswm of the foot may also be observed interossei ex-
terni of a penniform shape; they are attached to the fibular aspect
of the proximal phalanges of the toes. There was also an adductor
minim digiti, and interossei interni, but not any trace of transver-
salis pedis,

Mr. Owen concluded his observations with some remarks on the
structure of the principal joints of the lower extremity, and on the
degrees of mobility of which they are susceptible.

In the hip-joint the most remarkable circumstance is the freedom
of motion in the rotation inwards; this is, however, more limited
than in the opposite direction. The motions of flexion and ex-
tension, abduction and adduction, are also very free. On examining
the cause of the limitation of the inward rotation, he found it to be

N.S. Vol. 10. No. 55. July 1831. K a strong

66 Royal Institution of Great Britain.

a strong band of ligamentous fibres arising from the posterior margin
of the cotyloid cavity, and passing along the back part of the cap-
sule to the root of the great trochanter ; when this was divided the
rotation inwards was as free and extensive as happens in other cases
after a division of the digamentum teres. The synovial membrane is
reflected over a greater part of the anterior and upper than of the
back and under part of the cervix femoris. The marginal ligament
of the articular cavity is four lines in depth, a remarkable thickness
for the size of the cavity. The blood-vessels enter the joint by the
usual notch, and supply abundantly the process of synovial and
adipose substance called the gland of Havers.

The motion at the knee-joint is sufficiently free to allow the heel
to be brought to the buttock, and even beyond, as in natural
flexion it is carried external to the thigh. The only circumstances
remarkable in the structure of the joint are, that the internal lateral
ligament is longer, and the ligamentum mucosum stronger and of a
more ligamentous nature, than in the human subject.

The motion at the ankle-joint is so free, that the dorsum of the
foot can be brought into apposition with the fore-part of the leg;
and it is worthy of remark, that when this motion is produced, the
effect on the tendons passing behind the ankle-joint is such, as to
cause a flexion of the toes similar to that which is produced in
perching birds by bending the darsus upon the leg. In the opposite
direction the foot may be brought so far back as to form a right
angle with the leg. Lateral motion is also very free, especially the
turning of the sole inwards, to which aspect it naturally inclines.
A certain degree of motion is allowed between the first and second
set of tarsal bones. The ligaments of the ankle-joint are disposed
as in the human subject, one at the inner and three at the outer side.

The ligaments that connect the metatarsal bone of the thumb to
the internal cuneiform bone, are two in number, one at the upper
and the other at the lower or plantar aspect ; these limit the motions
of flexion and extension, but allow very freely abduction and ad-
duction. From this circumstance when the peroneus longus acts on
the foot in turning the sole outwards, its tendency to bend the me-
tatarsal bone upon the foot is resisted, and this bone is rendered a
fixed point without the necessity of the counteraction of a mus-
cular antagonist.

FRIDAY-EVENING PROCEEDINGS AT THE ROYAL INSTITUTION
OF GREAT BRITAIN.

May 27.—Mr. Britton: Remarks on and Illustrations of the Old
Domestic Architecture of England.

In the library, amongst many other things, were some Davy Pro-
tectors taken from the bottom of the Magicienne, now in dock at
Woolwich As usual, the iron had been removed to a great extent
by the action of the salt water, aided by voltaic influence, and had
left its bulk of that soft aggregate of plumbago, silicium, &c, remain-

ing under such circumstances. But it was curious to remark that the
mass

Intelligence and Miscellaneous Articles. 67

mass was impregnated with a substance resembling oil, which had
been formed by the union of the carbon of the iron with hydrogen
and oxygen, probably during the action of the water.

June 3.—Mr. Ritchie on Electricity, as the probable cause of all
the phenomena of artificial and terrestrial magnetism.—Mr. Ritchie’s
object was to bring forward a connected and illustrated view of what
had been done by Biot, Ampére, Barlow and others, in support of the
hypothesis here announced.

June 10.—Mr. Faraday on the arrangements of particles on the
surfaces of vibrating elastic bodies.—This was the same subject as
that of the paper, by Mr. Faraday, read lately to the Royal Society ;
and though treated experimentally and very differently at the Royal
Institution, yet as the philosophy of the two communications is the
same, a reference to our report of that paper, which will be found
at p. 42, will be sufficient here.

Mr. Faraday announced that since the reading of his paper, he
had reason to believe that the principles there referred to, combined
with the cohesive force of fluids, would enable him to explain the
crispations that form on water lying upon similar vibrating plates.
He is now engaged in these experiments.

This was the concluding evening of the Session.

VI. Intelligence and Miscellaneous Articles.

ACCOUNT OF AN AERIAL VOYAGE MADE IN A BALLOON ON
SATURDAY THE 30TH OF APRIL 1831, BY T. FORSTER, M.B.
F.L.S. &c.

O* Saturday, April 30, 1831, Dr. Forster, who had long been
desirous of pursuing his observations on the clouds in the lofty
regions of the air, engaged to ascend with Mr. Green’s balloon;
and at half-past five o’clock in the evening, the air being calm and
fine, and the barometer standing at 29-29, thermometer 63°, wind
variable and gentle, the aéronauts proceeded to the gardens of the
Dominican Friars at Moulsham near Chelmsford, and at a quarter
before six they left the ground, amidst the huzzas of hundreds of
spectators. The balloon, which was forty eight feet in vertical and
thirty two in horizontal diameter, and filled with carburetted hy-
drogen from the gas-works, rose at first with a gentle motion, and
was carried by a mild easterly breeze over the village of Writtle.
At the elevation of about a thousand feet they hung out the anchor,
which is found to give additional steadiness to the car; in a few
minutes more they perceived the balloon checked in its velocity,
and a change of current was evident; by this current they were
carried nearly back again, the balloon still ascending and pro-
ceeding, though very slowly, ina remarkably gentle S.W. current ;
when they had got beyond the N.E. end of Chelmsford, and
at the elevation of probably about four thousand feet, when nearly
over the Convent of New Hall, the current again changed; they
threw out some more ballast, and the balloon began to mount ra-
pidly in a sort of irregular spiral course, but so gently as to be
K 2 scarcely

68 Intelligence and Miscellaneous Articles.

scarcely perceived to move; till at length, at the altitude of nearly
six thousand feet, it became perfectly motionless, and so remained
for almost a quarter of an hour. Dr. Forster describes the sensation,
at this period, to be most delightful ;—balanced in the air, under
a floating and inflated bag, in a perfectly calm and tranquil region,
among the grotesque forms of evaporating clouds, and viewing in
delicious tranquillity a vast and apparently concave panorama of
country, bounded on one side by the sea, and everywhere inter-
spersed with towns and villages, and the yellow and varied tint of
the fields, the aérial travellers enjoyed a temporary repose from
the noise and bustle of the world, which is seldom felt on the sur-
face of the earth. More ballast being thrown out, the balloon
again rose, and Dr. Forster now felt a disagreeable sensation, like
pressure on the tympanum of the ears, just like what Garnerin,
MM. Charles and Roberts, and others have described; in conse-
quence of which he determined to open the valve, and they rapidly
descended again into an inferior current, which carried them to
Broomfield, where they eventually landed at twenty minutes before
seven o'clock.

During, and subsequently to this aérial voyage, Dr. Forster made
and recorded the following observations :

Ist. That the balloon, when rising gently, gyrated in the same di-
rection as the earth and planets do in their diurnal rotatory motion,
that is from right to left: this motion was however so gentle, that
it was only to be ascertained by observing objects below; in coming
down the balloon oscillated in the same direction.

Qndly. The currents of air which they successively met with in
ascending, came down during the next day in the same order
of succession: the S.W. wind for example, into which they got,
came down first on the following morning, and brought the rain.
From repeated experiments, Dr. Forster has reason to believe this
to be the case with most of the upper currents of air.

$rdly. The wavy cirrocumulus clouds are far beyond the reach
of all balloons, and even when the clouds are seen from the greatest
altitudes they seem as much above the ordinary clouds as they do
above the earth.

4thly. Dr. Forster in comparing his elevation in the balloon to what
he recollects of his Alpine ascents over the high Swiss mountains, is
induced to account for the less degree, and in his own case absence,
of giddiness experienced in balloons, to the idea of complete insula-
tion: as when a person hangs over precipices, or sits on pinnacles,
the notion of unsafe terrestrial attachment is the cause of the giddi-
ness. Dr. Forster noticed, during the voyage, the manner in which
clouds subside in an evening : he has also made some observations
on the peculiar effects produced by different circumstances of sail-
ing in boats at sea, and has compared them with those produced by
aérial floating, which he purposes, before long, to communicate to
the public; as also some physiological observations on the sea sick-
ness which some persons feel; and on the very peculiar deafness
experienced at great elevations, in diving bells, in mines, and on

change

New Patents. 69

change of weather, when the barometer rises or falls rapidly. One
remarkable observation which Dr. Forster made, was, that on the
occasion of descents from mountains, the deafness felt has always
been accompanied by a sense of fullness about the ears; but this
very unpleasant accompaniment of the difficulty of hearing was not
felt after the descent from the balloon ; the deafness in the Jatter case
being simply dullness of hearing. In both cases it soon goes off,
The sensation which is experienced when up in the higher regions
of the air is not actually deafness, but a snapping in the ears;
which goes off as one begins to descend; and the deafness which
comes on in descending still lower, and which is worse on arriving
at the ground, seems to be a sort of counterpart to the sensation ex-
perienced aloft. This very curious subject deserves further investi-
gation.

With respect to giddiness, and the fear of any danger from the
sudden falling of the balloon, Dr.Forster observes, that having been
accustomed to mount to very great aititudes, he felt neither of
these disagreeable annoyances ; but observed that on looking directly
down, at the grapple hanging below, and on the ground beneath,
he felt a disagreeable sensation, scarcely amounting to vertigo; but
such as would have become so in persons not accustomed to great
heights; and he therefore recommends aérial travellers to keep
their eyes on the horizon rather than the ground directly below
them, particularly if the car be large enough to admit of the choice.

The basket in which Dr. Forster ascended was a small one con-
structed for the purpose of lightness ; but he is constructing a light
circular willow basket capable of holding a proper set of instru-

ments, in order to be ready, should a fit opportunity for another
ascent occur.

P.S. Two parhelia were seen at five o’clock on Monday evening,
May 9th, at Chelmsford.

LIST OF NEW PATENTS.

To J. Revere, Weybridge, Surrey, doctor of medicine, for a new
and improved method of protecting iron chain cables, iron boilers,
and iron tanks, from the corrosion produced on them by the ac-
tion of water.—27th of November.—2Z months allowed to enrol spe-
cification,

To W. Church, of Haywood House, Warwickshire, esq-, for certain
improvements in apparatus applicable to propelling boats and driving
machinery by the agency of steam, parts of which improvements are
also applicable to the purposes of evaporation.—29th of November,
—6 months,

To R. Dalglish, junior, Glasgow, calico-printer, for improve-
ments in machinery or apparatus for printing calicos and other
fabrics.—6th of December —6 months.

To H, Blundell, Kingston-upon-Hull, merchant, for improve-
ments in a machine for grinding or crushing seeds and other olea-

ginous

70 New Patents.

ginous substances, for the purpose of abstracting oil therefrom,
and which machine, with certain improvements or alterations, is
applicable to other useful purposes.— 6th of December.—6 months.

To R. Edwards, Dewsbury, Yorkshire, leather and flock seller,
for an improvement on, or substitute for, glass, sand, emery, and
other scouring-paper or substances.—6th of December.—6 months.

To S. Brown, Billiter-square, London, Commander in the Royal
Navy, for certain improvements in the means of drawing up ships
and other vessels from the water on land, and for transporting or
mooring ships, vessels, and other bodies, on land, from one place
to another.—6th of December.—6 months.

To J. G. Lacy, Camomile-street, London, gun-manufacturer ;
and S. Davis, East Smithfield, Middlesex, gun-lock maker, for a
certain improvement or improvements in the construction of guns
and fire-arms.—6th of December.—6 months.

To J. Dixon, Wolverhampton, and J. Vardy, of the same place,
for certain improvements in cocks for drawing off liquids.—1 3th of
December.—2 months.

To T. Walmsley, Manchester, manufacturer, for improvements
in the manufacture of cotton, linen, silk, and other fibrous substances,
into a fabric or fabrics applicable to various useful purposes.—13th
of December.—6 months.

To W. Needham, Longour, Staffordshire, gentleman, for certain
improvements in machinery for spinning, doubling, and twisting, silk
and other fibrous substances.—13th of December.—6 months.

To S. Parlour, Croydon, Surrey, gentleman, for certain improve-
ments on lamps, which he denominates Parlour’s Improved Table
Lamps.—13th of December.—2 months.

To J. L. Benham, Wigmore-street, Middlesex, ironmonger, for
certain improvements on shower and other baths, Communicated
by a foreigner.—13th of December.—6 months.

To R. Witty, Basford, in the parish of Wolstanton, Staffordshire,
engineer, for certain improvements in apparatus for propelling car-
riages, boats, or vessels, and for other purposes, by the power of
steam.—13th of December.—6 months.

To B. Redfern, Birmingham, gun-maker, for a lock, break-off,
and trigger, upon a new and improved principle, for fowling-pieces,
muskets, rifles, pistols, and small fire-arms of all descriptions —Dated
the 17th of December 1830.—2 months.

To A. Graham, a citizen of the United States of North America, but
now residing in West-street, Finsbury, London, gentleman, for cer-
tain improvements in the application of springs to carriages. Com-
municated bya foreigner.—17th of December.—6 months.

To D. Papps, Stanley End, in the parish of King Stanley,
Gloucestershire, machine-maker, for certain improvements in ma-
chinery for dressing or roughing woollen cloths.—23rd of December,
—2 months.

To W. Wood, Summer Hill, Northumberland, near Newcastle-
upon-Tyne, for the application of a battering-ram to the purpose of
working coal in mines.—23rd of December.—4 months.

To

Lunar Occultations in July 18$1. 71

To M.E. A. Pertius, No. 56, Rue du Bac, Paris, spinster, for the
fabrication or preparation of a coal fitted for refining and purifying
sugar and other matters. Communicated by a foreigner.—23rd of
December.—6 months.

To J. Ferrabee, Thrupp Mill and Foundry, Stroud, Gloucester-
shire, engineer, for improvements in the machinery for preparing
the pile or face-of woollen or other cloths requiring such a process.
—23rd of December.—6 months.

To J. Blackwell and T. Alcock, both of Claines, Worcestershire,
machine-makers, and lace or bobbin-net manufacturers, for certain
improvements in machines or machinery for making lace, commonly
called bobbin-net.— 13th of January, 1831.—6 months.

To S. Seaward, Canal Iron Works,in the parish of All Saints,
Poplar, engineer, for an improvement or improvements in apparatus
for ceconomising steam and for other purposes, and the application
thereof to the boilers of steam-engines employed on board packet-
boats and other vessels.— 15th of January.-—6 months.

To W. Parker, Albany-street, Regent’s Park, gentleman, for
certain improvements in preparing animal charcoal.—15th of Ja-
nuary.—4: months.

To J. and G, Rodgers, Sheffield, cutlers; and T. Fellows, jun.
New Cross, Deptford, gentleman, for an improved skate.—18th of
January.—2 months.

To A. Smith, Princes-street, Leicester-square, St. Martin's in the
Fields, engineer, for certain improvements in machinery for pro-
pelling boats and other vessels on water, and in the manner of con-
structing boats or vessels for carrying such machinery.—22nd of
January.—6 months.

To J. G. Ulrich, Nicholas Lane, London, chronometer-maker,
for certain improvements in chronometers.—22nd of January.—
18 months,

LUNAR OCCULTATIONS.

Occultations of Planets and fixed Stars by the Moon, in July 1831.
Computed for Greenwich, by THomas Henperson, Esq. ; and
circulated by the Astronomical Society.

Immersions. Emersions.
j Angle from
Stars’ Angle from 4

1831. Names, Sidereal| Mean ; |Sidereal} Mean

Magnitude.
Ast. Soc. Cat.
No.

: ‘ ¥ foveal tedtegs| aie
time, |solartime, 5 g £ time, |solartime. | 3
I
of oo C)
ZAM] ip zm!
EIS So ER ae al i lr TH pe) (PRR PRE Rr fal i |
eit) HV h-| 5 hm). om} 5

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‘(penunuos) ATV

ANNUAL

N. S. Vol. 10. No. 55. July 1831.

74 Meteorological Summary for 1830.—Hampshire.

ANNUAL RESULTS FOR 1830.

Barometer. Inches.
Greatest pressure of the atmosphere, March 26. Wind N. W. 30-620
Least ditto ditto January 20. Wind E. 28-600
Hapge-of the quicksilver- vc 6. = rye. cok lov oy be oe ck Bek 2-020
Annual! mean pressure of the atmosphere .........+..... 29-918

Mean pressure for 175 days with the moon in North decl. 929-930
for 179 days with the moon in South decl. 29-951

Annual mean pressure at 8 o’clock A.M. .............. 29-917
at’ DO; CLOCK Tee Mn temas Bete arch 29-919
ah OS COC ae eer eis Se a 29°920
Greatest range of the quicksilver in January............ 1-990
Least range of ditto in October: >see Sens} 0°750
Greatest annual,variation in 24 hours in January ........ 1°050
Least of the greatest variations in 24 hours in May ...... 0-330
Aggregate of the spaces described by the rising and falling
GP the quite ks W yer. Se orw-aais wea cw eter vee -wrereier th eee 72'330
INGER GN CUANDO ss ne wens Stoke vel rele uN hoe Eke. Sate ae 234
Six’s Thermometer. Degrees
Greatest thermometrical heat, July 29. Wind E.......... 84
ee cold, February 2. Wind N.E..... 13
Range of the thermometer between the extremes ........ ia
Annual mean temperature of the external air........... 49°80
ee at 8: ALM. .% 2 48°33
—_—_—- ————- at 8 P.M..... 48°85
Oe I eee at2 P.M, .... 5409
Greatest range in Pourmary so). a... - cee ene fee aoe 40:00
Least of the greatest monthly ranges in September....... 24:00
Arnal Mea TAREE: he jane ee pee Argan eicistre <j e+ ass 30°75
Greatest monthly variation in 24 hours in February ....... 26-00

Least of the greatest variations in 24 hours in November .. 16°00
Annual mean temperature of spring-water at 8 o'clock A.M. 50-29

De Luc’s Whalebone Hygrometer.

Degrees.
Greatest humidity of the atmosphere, in April............ 100
Greatest dryness of ditto, in March,............-00000 46
‘Range of the index between the extremes.............. 54

Annual mean state of the hygrometer at 8 o’clock A.M... 738

———_ at 8 o'clock P.M... 78°5
—————_——_——_—_ ————~ at 2 o'clock P.M. .. 68-2
— -——- at 8, 2, and 80’clock 9 73°5
Greatest mean monthly humidity of the atmosphere in Feb. 82:3
dryness of dittoin May........ 65°3

Position

Meteorological Summary for 1880.— Hampshire. 75

Position of the Winds. Days.
From North to North-east..............2.. 32
North-eastanowtiastywici-t o> cissverein’ «'bi «fs 42
=== ast LO MSO AeAStr aw. Lal vor eicieiace cla tute
=) SOUP CAS PLO OULD pele had cite caialien Pelei soso 42
as\-> Sonthtomsouti-West a.) niaciesee ceté chess 16

=== Sonthemesu to, WES. 2. 2. eects) ccarele 965

a2 = - WEEE OR NOEL AWESL co. aman ole ond oes 575
— i NOTteNVERS LO. NOLEDis 5,60. Se eehy oe serie « 52

365

Clouds, agreeably to the Nomenclature, or the Number of Days on
which each Modification has appeared.

Days: Days
CIDTUS ro 40 1. es 234 Onorulusges oss. 209
Cirrocumulus.. 119 Cumulostratus... 217
Cirrostratus... 333 NIM DESIR Ai, Oerercte 199
Stratis... « HP nage:
General State of the Weather. Days.
A transparent atmosphere without clouds... .. 49
Fair, with various modifications of clouds..... 1572
An overcast sky without rain............... 965
ye SLPS SO Ae ote ati min wie a alate tele 5
Rainy haily-and-snow soi 2 wre Seater sselave steerer 57
365
Atmospheric Phenomena. No.
Anthelia, or mock-suns opposite to the true sun 2
Parhelia, or mock-suns on the sides ofthetrue sun 14
Paraselenz, or mock-moons...........2-+e+ 6
DIAN URLOS Recs serrata sa rcisie tee exe. ° aputicse oats ee
MEIGS ahr ct en eae eens eoske, aa cg cco s.s 21
Rainbows......... Pa ESTO I TT 14
eens teenies sere, eee ent 8 90
PENIEE TE! OOTEMIER fe. Ate oot eGtare ole wines < * ple ly
Lightning, days on which it happened...... pats 4
Thunder, ditto Ni Waa ge gas lea laa 5
Evaporation. Inches.
Greatest monthly quantity in May.........- 4°80
Least monthly quantity in February........ 0°72
Total amount for the year....... Sete atels. wore. 28°60
Rain.
Greatest monthly depth in November......--- 4695
Least monthly depth in October..........+-- 0°595

Total amount for the year, near the ground,... 28*350

The instruments with which the observations were made are the
same as those in former years, with the exception, that instead
of the horizontal thermometer, a Six’s thermometer has been used.

L2 BAROME-

76 Meteorological Summary for 1830.— Hampshire.

BAROMETRICAL PressuRE.—The mean pressure this year is
+i, of an inch higher than the mean of the last fifteen years ; but
the number of changes is less than in any year in that period.

On the 19th of January a depression of 1:05 inch of mercury
occurred, with a strong wind, first from South-east, and then from
the North-east, accompanied with a heavy fall of snow.

The mean of the pressures at 8, 2 and 8 o’clock coincides with
the annual mean pressure.

TremMPERATURE.—The mean temperature of the external air this
year is lower than that of any year since 1816. The mean tem-
perature of January and the first part of February was very low,
and we have never registered so low a degree of temperature as
that which occurred in the night of the 2nd of February. There
is a difference of half a degree between the annual mean tempera-
ture at 8 A.M. and 8 P.M., the latter being the highest. The
annual mean temperature of spring-water this year is the lowest
during the last ten years.

Winps.—The duration of the South-west wind this year is un-
precedented, being more than one-fourth of the period; the wind
from the West is the next in duration; but that from the South
has prevailed the least number of days.

The North-east and South-east winds are equal in point of time.

The number of strong gales of wind, or days on which they have
prevailed this year, is as in the following scale:

N. | N.E.| E. | S.E.| S. |S.W.| W. | N.W.| Gales.

Ay | bos |. i 6 45 )| ASH 8) 4) 103

January was very cold and cloudy, with frequent falls of snow ;
it having snowed more or less on fifteen days.

February was rather dry and mostly frosty, with a cloudy atmo-
sphere, and occasional gales of wind. The minimum temperature
in the night of the 2nd was the lowest that had occurred the last
fifteen years,

March was fine, calm, and very dry, and a high pressure pre-
vailed the latter part of the month, when the spring began to open.

April commenced with a snow-storm for several hours, and was
alternately fine and showery, with frequent strong gales. In the
night of the 4th the frost was severe, and did much injury to the
bloom of the trees in open situations. Vegetation was checked the
first part of the period by the cold nights and hoar frosts; but
the warm rains, followed by clear sunny days during the latter part,
caused a rapid growth.

May was dry and pleasant, with much warm sunshine till the
20th, when the air became arid and blighty, and the roads very
dusty, insomuch that vegetation began to droop. The latter part
of the month was showery, accompanied with strong gales.

June was cold, showery and windy. The crops of grass, from
the nature of the weather in the spring, were generally sat

ut

Annual Meteorological Results at Penzance. 77

but from a continuance of wet, much of the early cut grass was
spoilt before it could be put in ricks sufficiently dry.

July was also cold, showery, and windy till the 12th; but the
latter part of the month was fine and dry, with four or five hot
days and nights, which matured the wheat.

August was fine and dry till the 8th, during which time much
exertion was made by the agriculturists in securing the wheat
crops. The remainder of the month was showery and windy ; and
as scarcely any good opportunity occurred to get in the wheat in
a dry state, much was lost out of the standing sheaves in the fields
before it could be carried.

September was wet and windy, which occasioned difficulties in
getting in the barley and oat crops, both of which were abundant,
and far superior in quality to those of several years past. The fruit
crops were also abundant, but they were generally deficient in na-
tural flavour, and mostly worm-eaten.

October was very dry, calm, and fine, with a high atmospheric
pressure.

November was boisterous and wet, which caused floods in many
places; but the air was mild for the season, with the exception of
a few days.

December was also wet and windy, and after the 10th, cold and
frosty, with snow at intervals, and a low pressure.

The frequency of aurore boreales in the autumn was remarkable:
fair descriptions of their appearances may be seen under the monthly
meteorological reports in this work.

Extract from the Meteorological Journal kept at Penzance by Mr.
Gippy.

ANNUAL RESULTS.

Register de

rometer. 7

Barometer Thermometer. 3 3
Se
25
py

30°50 | 29:00 |29:970 | 48 | 23 | 37:0
30:20 | 29°45 |29°877 | 53 | 19 | 40:0
30°32 | 29.35 |30°018 | 61 | 39 | 48'8
30°10 | 29°20 |29°735 | 62 | 32 | 49°5
30°25 | 29°30 |29°814 | 65 | 42 | 54:5
30°10 | 29°30 |29°830 | 67 | 45 | 567
30°20 | 29°32 |29°895 | 76 | 49 | 60°5
30°25 | 29°40 |29°835 | 68 | 47 | 58:3
30°30 | 29°25 |29°805 | 64) 45] 55°4
30°40 } 29°82 |30:120 | 62 | 43 | 54:0
30°30 | 28°95 |29°730 | 58 | 39 | 49°5
30°40 | 28-60 |29-625 | 53 | 25 | 43:0

30°50 | 28-60 |29°8546) 76 | 19 | 50°6 |42°475/175 |190

1829 | 30°50 | 28°85 |29°8710) 71 | 19 | 50°4 |43:045 |182 183. NW.

The rain-gauge is at the ground-level, and the dry days comprehend
those days on which no fall whatever takes place,—not the slightest
shower.

METEORO-

78 Meteorological Observations for May 1831.

METEOROLOGICAL OBSERVATIONS FOR MAY 1831.
Gosport :—Numerical Results for the Month.

Barom. Max. 30-303, May 9. Wind N.E.—Min. 29-478. May 1. Wind S.
Range of the mercury 0-825.

Mean barometrical pressure for the month ......... Shep secseeeeeee 29-920
Spaces described by the rising and falling of the mercury....... coves 4096
Greatest variation in 24 hours 0:286.—Number of changes 22.

Therm. Max. 72°. May 25. Wind S.E.—Min. 35°. May 6. Wind N.
Range 37°.—Mean temp. of exter. air 54°76. For 31 days with © in 6 52°85
Max. var. in 24 hours 20°:00.—Mean temp. of spring-water at 8 A.M. 49-60

De Luc’s Whalebone Hygrometer.

Greatest humidity of the atmosphere, in the evening of the 29th.... 94°
Greatest dryness of the atmosphere, in the afternoon of the 18th... 43
Fear gcse Miesete tate sacnecs crates ancsacaesssuccsanvesaasoneccesstaaane 51
Mean at 2 P.M. 57°-5.—Mean at 8 A.M. 62°-7,—Mean at 8 P.M. 68°5
of three observations each day at 8, 2, and 8 o’clock.......... 62:9
Evaporation for the month 6-35 inches.

Rain in the pluviameter near the ground 2-07 inches.

Prevailing winds, S.E. and N.E.

Summary of the Weather.

A clear sky, 53; fine, with various modifications of clouds, 1533; an over-
cast sky without rain, 43; rain, 53.—Total 31 days.

Clouds.
Cirrus. Cirrocumulus. Cirrostratus. Stratus. Cumulus. Cumulostr. Nimbus.
25 10 25 0 22 15 13

Scale of the prevailing Winds,

N. N.E. EeeSBe Se eS Wie Wick Nn Days.
33 8 4s 85 2) ay 1 1 31

General Observations—This month has been alternately wet and dry ;
the dry period was from the 5th to the 19th, during which time no rain
fell here, and the air was frequently arid with a North-east wind, accom-
panied with a great evaporation.

For several days upwards of three-tenths of an inch evaporated, and on
the 18th, the day before the rain came on, half an inch in depth ascended
from the evaporator, which clearly indicates the greater power of the air
in eliciting heat, and carrying off so much moisture from near the surface
of the earth immediately before the change from dryness to rain, and
which was verified by the hygrometer’s, then pointing out the maximum
dryness for the month.

There were several hoar frosts in the first part of the month, when great
blights prevailed, and their effects have since been made manifest by the
trees being much thinned of their fruit. Comparatively speaking there
were but a few warm days this month, and the mean temperature of the
external air is about one degree under the mean of May for many years past.

On the 5th, at three P.M. a heavy flash of lightning was experienced
here, and was succeeded by a loud clap of thunder; distant thunder also
frequently occurred in the morning of the 24th.

At half-past ten o’clock in the night of the 30th, a few light corasca-
tions ascended due North from an aurora borealis, which was low in the
Northern horizon, and two meteors fell over it. This may be considered
late in the spring for its appearance, as the evening twilight in that quarter
is getting long, and being of a similar appearance to that of an aurora, it
renders it imperceptible in the summer months, fail

he

Meteorological Observations for May 1831. 79

The planet Mercury was seen here with the naked eye in the fine even-
ings, from the Ist to the 13th; and Venus was seen at ncon of the 16th,
notwithstanding she is still in the superior part of her orbit.

The atmospheric and meteoric phenomena that have come within our
observations this month, are one solar and two Junar halos, two meteors,
one rainbow, one aurora borealis, lightning and thunder on the 5th, distant
thunder on the 24th, and four gales of wind, namely, two from the North-
east, and two from the East.

Occultation of Jupiter and his Satellites by the Moon.—The following
were the apparent astronomical times here, on June the Ist, when the
immersions and emersions of Jupiter and his Satellites occurred, with the
exception of the 4th Satellite, the times of whose immersion and emersion
are given by approximation.

IMMERSIONS. EMERSIONS.
The 4th Satellite at... 12"40748* | The 4th Satellite at ... 132497 6°
The lst Satellite at... 12 57 50 | The lst Satelliteat ... 14 6 10
Jupiter’s western limb at 12 59 49 | Jupiter’s western limb 14 7 50
Jupiter’s centre at ..... 13 1 45 ) Jupiter’s centre at...... 14 9 47
Jupiter’s eastern limb at 13 3 42 | Jupiter’s eastern limbat 14 11 45
The 2nd Satellite at... 13 6 10 | The 2nd Satellite at... 14 12 25
The 3rd Satellite at... 13 10 41 | The 3rd Satellite at... 14 17 43

The occultation of Jupiter lasted 1 hour 8 minutes 3 seconds, From
the motion of the Satellites the times of their occultations do not exactly
agree with that of their primary.

Jupiter was not so nicely dichotomized on the Moon’s enlightened limb
as on her dark side: and after his emersion he appeared with an apparently
enlarged disc, and shone more brilliantly than before his immersion, as well
as his Satellites.

REMARKS,

London. — May 1. Cloudy: showers. 2. Heavy rain, with thunder.
3. Showers: fine at night. 4. Showers, with intervals of bright sun.
5. Fine in the morning: showers: clear and cold at night. 6. Fine: cloudy:
clear at night, with severe frost for the advanced state of vegetation.
7, 8. Fine: frosty at nights. 9—13. Fine, but cold and very dry. 14. Fine:
slight frost at night. 15,16. Fine. 17,18. Verydry. 19. Fine: rain at
night. 20. Cloudy: heavy thunder shower in the afternoon. 21, 22. Over-
cast. 23. Cloudy: thunder in the afternoon. 24. Fine: dull and hazy,
with thunder at night. 25—28. Fine. 29. Wet. 30. Cloudy: fine.
31. Foggy in the morning: fine.

Penzance.—May 1. Fine. 2,%.Clear: showers. 4,5, Fair: hail showers.
6—s. Fair. 9, 10. Clear. 11. Fair. 12, 13.Clear. 14, 15. Fair.
16. Clear. 17. Fair. 18. Clear: a shower. |19. Fair: rain. 20, Fair.
21. Clear. 22. Fair, 23. Fair: foggy. 24. Foggy: fair. 25. Fair.
26. Fair: rain at night. 27.Rain. 28, Fair: rain. 29. Rain. 30. Fair:
rain. 31, Rain.

Boston. — May 1.Fine. 2.Cloudy. 3.Rain. 4. Cloudy: rain a.m.
andpv.m. 5.Fine:rain p.m. 6,7. Fine. 8.Cloudy. 9—12. Fine.
18—15. Cloudy. 16—19.Fine. 20, Cloudy: shower p.m. 21. Cloudy.
22.Fine. 23, Cloudy: rain, with thunder and lightning early a.m, 24, Fine.
25. Cloudy. 26, Fine. 27—30.Cloudy. 31, Fine.

Meteoro-

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THE

PHILOSOPHICAL MAGAZINE

AND

ANNALS OF PHILOSOPHY.

——.

[NEW SERIES. ]}

AUGUST 1831.

VII. On some Problems in Analytical Geometry. By
J. W. Lussock, Esq. V.P. § Treas. R.S.*

Lt the equation to any curve surface of the second order
be

Ar +Cy?+Ke+ Bry+ Lzy+ Mrz+ Du+ Ey+ Nz4+F=0,
(F (Xs Ys z) = 0)

the coordinate axes x, y, x being inclined to each other at any

angle, and let ¢ be the distance of any point (#, 8, y) from

(x,y %), (25%, =) being situated on the curve surface.

ge? = (w—a)? + (y—B)* + (zy)?

+ 2(c—a) (y—B) cosxy + 2 (y—B) (zy) coszy +
2(z—y) (w@—a) cosxz (1

If Q is a Maximum or minimum and A is some indeterminate
quantity,
a{2de+ By+ Ms+ D}\ =2-a+(y—f)costy+(z—y) cosrx (2)
af{2Cy+ Br+ Lz +E} =y-B+ (e—«) cosry+(z-y) cosey (3)
a{2K24+Ly+Me+ N} =2-y+(e—«) coszxr+(y—P) coszy (4)
Eliminating 4,

{2Ar+ By+Mz + Di {y—B + (t—2) cosay + (z—y) cos zy}
={2Cy+Be+ Le+ E} {e—a + (y—f) cosry +(2—y) cosrs} (5)

{2 Cy+Bea+Let+ E}{ s—y + («—«) cos za + (y—f) coszy}
={2k2+ Ly+Mr+N}{ y—B + (e—«) cosy + (s—y) coszy} (6)
which are the equations to curve surfaces whose intersections

determine the points from which the normals can be drawn
from the point «, 8, y to the curve F' (2, y, 2).

* Communicated by the Author,

N.S. Vol. 10. No, 56. Aug. 1831. M Let

82 Mr. Lubbock on some Problems in Analytical Geometry.

Let D=0, E= 0, N= 0; then multiplying equations (2)
(3) and (4) first by x, y and z respectively, then by e—a, y—B
and z—y respectively, and then by «, 8, y respectively, and
adding together the results, # being the distance of the point
a, B, y from the centre, and r the distance of the point in which
the normal cuts the curve surface, from the centre,

ra=r+yt+ 24+ 2xry cosxry+2zycoszy + 2ercossx
R= 248 +7°+ 2aPcosry+2yBcoszy+2yacoszx
» is therefore evidently independent of the direction of the
axes X, ¥/, 2
Eliminating 2, y, z from the equations
A{2Ax+ By + Mz} =x2+ ycosxy +2 cos xz
A{2Cy+ Bat+ Lz} =y+xrcosry + zcoszy
a{2Kz+Ly+ Mr} =2+4+ rcoszx + ycoszy
which obtain upon the supposition that a, 6, y = 0, in which
72

Casey A "a.
2F
7?
4k#C4+4404+44K4+2°4+ B24
—2F*) —2BLcoszr—2BMcoszy —2ML cosyr pr
8AKC —2 AL2—-2K B’—-2CM*? —2MLB

—cos xx cos xy) —2 M (cos xr— cos ry cos xy)
8AKC—2AL? —2K B-2CIM-2MLB

2Csin?sxr+2 Ksin2ry +2 sin?zy
44 F: —2L (cos zy—cos xx cos vy)— 2 B (cos ry a

—8 F3) 1— cos? zy — cos?ry — cos*ze+ 2cos xx cosry cosz
1 y y ycoszy} _ G4
8AKC—2AL2?—-2K B2—2CM*—2MLB rg

If m,n, p are the principal axes of the surface,
the coefficient of * = m? +n? + p?
of 7? = mp? + m?n? + n2p?
and the quantity independent of 7 = m? n° p* because m?, n*, p
are evidently the roots of the equation.
If the curve surface be referred to conjugate axes m’, n!, p’
so that

3

Az=m' pl, C = m?n?, K = m?n?
B=0, L=0, M= 0, F=—\n? nip?
re a (m’? i nie 4 p) rs
+(p? rn? sin? yz + p? m” sin? z 2 + mn? sin? x y) 1°
—m! n! pl? (1 —cos? zy—cos” © y—cos® 227

+2 cos zx cos xy cos zy) = 0.
Whence

Mr. Lubbock on some Problems in Analytical Geometry. 83

Whence
m'? + n? + p® = m® + n° + p
pin? sin?y + p? m2 sin? zx + mn! sin * xy
=pnr+pm + m? n?
m!? nip? (1 —cos? zy—cos® xy —Cos*2 x +2 COs 2x COS TY COS zy)
= mn? p®
which are the known properties of the conjugate diameters ;
the first and third of these theorems appear to have been first
proved by M. Livet, in the thirteenth Number of the Journal
de ? Ecole Polytechnique; and the second by M. Brianchon
in a memoir “ Sur la Théorie des Axes conjugués, et des Mo-

mens d’Inertie des Corps,” Journal de ? Ecole Polytechnique,
vol. viil. p. 65. .

If a’, y/, 2! are the coordinates of any point in the normal

drawn from the origin, which coincides with the centre, of the
curve surface,

Av 4+Cy+K24+Bay+Lzey+ Mer+F=0
ay! vz
a eee
(2 Aa! + By! + M2) (y +2 cosay+ 2 cos zy)
= (2Cy+Ba + Lz) (e+ y coszy + z! cos x z)
(2Cy' + Bal + L#) (2 + a cosza + y' cos zy)
= (2K2 4+ Ly + Mo’) (y+ a cosry + z! cos zy)

which are equations to conical surfaces whose intersections are
the principal axes of the curve surface,

Av? + Cy 4+ K2+ Boy+ Ley + Mrz + F=0.
Transferring the origin to the point a, P, y
Adc +Cy+K2+Bry+Lzy+ Mez+ Dat Eyt
Ng + £='0
D=-—2Aa—BB-—Cy
E =—2C6—-—Ba—Ly
N=—2Ky—L6-—Mae
foAr + By + Mi +D} {y'—B + (a'—a) cosry + (xy) cos ty }
={2Cy + Be +L? +E} {af—a + (y’—B) cos Ty +(x/—y) cos x}
{2Cy + Bo + Le + EB} {2 — 7 + (2-4) (cosee + (y!—B) cos xy}
={2K/+Ly +Mz +N} {y/— B + (2-4) cos zy + (x'—y) cos zy}

In order to have the equations to these conical surfaces
which determine the principal axes in the most general case
possible, it is only necessary to substitute in the preceding

M2 equations

84 Mr. Lubbock on some Problems in Analytical Geometry.

equations the values of «, 6, y, found by elimination, in terms
of A, B, C, D, E, L, M, N from equations of lines 29, 30, 31.

If the equation to the curve surface be in the form
n? p? x? +m? p?y? + mn? 2° = m? n? p*, and a, 8, y are the co-
ordinates of the point, as before, from which normals are drawn,

my (w—a) = na ( y—B)

n° x (y—B) = py (2-7)

pa (z—y) = mz (4—a)
These are the equations to cylinders which have for their bases
equilateral hyperbolas, and which pass through the centre of
the curve surface and the point «, f, y.

Let 2’, y',2' be the coordinates of any point in the normal
drawn from the point «, 8, y to the point x,y,z in the curve
surface, .

t—a w—a z—a 2-4
ype 6 zy Ry
Eliminating 2, y, z between these equations,
(ay —B a)? {m?(z'—a) + n° (y'—BY + p?(2—7)}
= (n?—m’)? (2! —a)? (y/—B)?
(ya! —a y!)? {m? (a! —a)? + n® (y'—B)? + p? (n'—yP}
= (m?—p?) (ey)? (e=2)°
(6 z'—y y')? {m? (a'—a)? =f n? (y'—6)? + oy (2! —y)*}
= (p—m®)? (y'—8)? (2!)
which are the equations of conical surfaces whose intersections
are the normals which can be drawn from the point a, f, y to
the curve surface,
The equation to the cone which circumscribes the surface
n? p? x* de m? p* y? ate m? n2 x? — m? n® p*,

and whose vertex coincides with the point a, 8, y, is

n? p*(x—a)* + m? p? (y—B)? + mn? (2-7)?

— p* (Bx—ay)?—m? (az—yx)*—n* (yy—B2)? = 0;

and the equation to the plane of contact is

wpac+mp By +n? myz = mn? p*
These equations relative to the circumscribing cone are given
in various works on analytical geometry.

If the ellipse

ng? + m? y? = m2 nt
be considered, and if the axes x and y, be at right angles,
Ax = m (x—a)
ay =n? (y—B)

and

Mr: Lubbock on some Problems in Analytical Geometry. 85
and eliminating A,
(m?—n*) ry—may+ npr =0
which is the equation to an equilateral hyperbola (see fig. 1.),

which cuts the ellipse in the points to which normals can be
drawn from the point a, 8. The asymptotes to the hyper-

bola are parallel to the principal axes of the curve; it passes
through the centre and the point (a, 6) ; the coordinates of
2 n?
m—n

its centre are When « or 8 = 0,

m?—n*
the hyperbola merges into two straight lines at right angles
to each other; and when the point («, @) coincides with the
centre, these lines become the principal axes of the curve.

If the equation to the curve be y° = 2p, the equation to
the corresponding hyperbola is

ry —(e—p)y+ pp = 0.

The centre is situated on the axis of the parabola at a distance
a — p from the vertex. This construction is given by Apol-
lonius. See Bossut, Histoire des Mathématiques, vol. i. p. 37.
If 2! and y' be the coordinates of any point in the normal,
a! —a Sabah Dipelleg
"doer OR mae
and eliminating x and y between this equation and the equa-
tions
n? x + my? = m?n?; (m°—n*)cy—may +n’ pe = 0,
we have :
fm? (x!—a) + n*(y'—p)?} {Br—ay}?—(m'—n'y (a'—a)* (y'—AY = 0

which is the equation to the normals drawn from any point

ape.
When m = 2, the ellipse becomes a circle; in this case
pam

86 Mr. Lubbock on some Problems in Analytical Geometry.

62—ay = 0, which is the equation to the line joining the
centre of the circle and the point « 6.
It is evident that since the hyperbola
(m?—n*?)xny—mayt+n’px=0
is the same for all similar ellipses, there will be one, as fig. 1.,
which touches the hyperbola.

In this case two of the normals, as P N;, P N,, coincide and
become equal ; after this the ellipse diminishes, one branch of
the hyperbola ceases to cut the ellipse, and only two normals
can be drawn from the, point «£ to the ellipse.

When the ellipse touches the hyperbola, the values of aa

are the same in both.
Let 2/2? + my? = n/m’ be the equation to this ellipse,
then
{ (m?—n*) 2—m*? ain’? 2 = my {(m?—n*)y + n? B}
nm on?

and since — > ——
m2 m!?

{(m?—n?) c—m*a} n? x = my {(m°—n°) y + n° B}
and eliminating x and y between this equation and the equa-
tions
(m? — n®)xy—mayt+nwBar =O
and my? + n? x = mn?
m—n? = fit ot 4+ n3 Br }+
the equation to the evolute of the ellipse.
And hence from any point within the evolute of an ellipse

four normals can be drawn from any point to the curve, from
any point without it only two.

On the Determination of the Foci.
Let n° x? + my? = m? n°
and let the the curve be referred to any other coordinates
x! and y' by putting
a(x! +a!) + b(y + B') for x
and a’ (a! + a!) + U(y' + 6’) for y
Ax? + Bay + Cy? + Da+ Ey+iF=0
A=ra+ma?®, B=2(n?ab+ ma'l), C= n?b?+ mb”
D=2 (naa! + nab pl + ma?a + mabp’)
E = 2(n?b? pl + n2 b? a! + m? bd? B! + m? b? a!)
F = n2 a al? 4 n2 6? BP +2n? a!B! +m? be? iS eb 2 m2? al ba! B! —m* n=
Now let the equation 42!+ Ba'y! + Cy? + Da'+ Hy’+F=0
be

Mr. Lubbock on some Problems in Analytical Geometry. 87

be transferred to polar coordinates by putting ra" for x" and
rb" for y',r being the distance of any point from the origin,

(Ad? + Bab" + CBP?)r? + (Da! + ED')r+ F=0

—Da’—Eb!
iis { + {(D?—4AF) a? + 2(DE —4BF) a’ b” \
+ (E—4cF) 0"
2 (Ad ae Ba' pl ae Cor)

and since a? + J? + 2a"b"cosry = 1

— Da'!—Eb’”
r =| { D’—4 AF + 2(DE—2 BF— D?—4 AF) cos a}
+{H?—4 CF—D°+4AF}b"}2
YX, (A qll2 ae Ba! bl + Co)
which value of 7 will be rational in terms of a” and Bb” if

F?—4CF—-D’?+4dF=0
DE—2 BF — (D—4AF) cosxy =0
putting for A, B, C, D, E and F their values above, it will be
found, after many reductions, that these equations may be put
in the form
(a’b aE ab’ (p? a al?) —_ (a® a 6?) m2 a n2
(ab —al/) (a! 6+ BP? cosx’y’) = (n?—m?*) (a? cos a! y! — a b)
In these equations «' and 6! are measured from the center
of the curve in the direction of the axes x’ and y': the equa-
tions to the same curve, found either by similar substitutions
for the quantities 4, B,C, D, Z, and F' or by transforming
the last two equations, referred to coordinate axes coinciding
with the principal axes of the curve, are
(a°—b”) (a?— 6") + 2 (bb’—aa') aB = (a*—b”) (m?—n?2)
aa’ (a#°—B*) + (a°—b”) a8 = aa! (m?—n?)
making 8 = 0 in these equations
e=m—n, a= + Wf (m—n?)
making « = 0, B= + Vo (n?—m?)

If m > n, the latter value of 6 is imaginary, and therefore
these curves cut one another in two points only, which are si-

tuated on the major axis at the distance + 4/ m?—n” from the
centre. This result is entirely independent of the quantities
a, b, a’, ’, that is, of the direction of the axes 2’ and y/; and
hence it is evident that there are only two points from which
the distance r to the curve is rational in terms of a” and b”.
These points are called the foci.

The

88 Mr. Nixon on the Measurement of the

The curves whose intersections give the foci are equilateral
hyperbolas. (See fig. 2.)

It is easy to show generally that the equation to the curve
mene Av?+Bry+Cy+De+Hy+F=0,
the foci result from the intersection of the curves:
{ B?—4 AC} (2°—y*) + {2 BE—4 DC} wx—{2 BD—-4 EAhy
+ B-—4CF-— D?+4AF=0
§ B—4ACtay+ {BD—2AE}x + {BE—2DCily+2BF—ED

—}{B—4 ACh + {2BD—4 AE} y+ Di—44 Fhoos xy =0

VIII. Particulars of the Measurement, by various Methods, of
the instrumental Error of the Horizon-Sector described in
Phil. Mag. vol. lix. By Joun Nrxon, Esg.*

pee horizon-sector may be described, sufficiently for our

present purpose, as a telescopic-level, having attached to
each side of its telescope a vertical plate with a divided arc
carrying at the centre of the divisions a short horizontal axis
on which moves an index supporting a spirit-level. The Ys
are fixed to a bar of brass, of which one end, formed into a
sort of horizontal axis, connects the bar to a frame or stand
beneath, which latter serves, by means of rack-work, &c. to.
raise or depress the telescope.

* Communicated by the Author: see Phil. Mag. vol. lix. p. 130.
First

instrumental Error of his Horizon-Sector. 89

First Method.—By finding the horizontal inclination of the
upper surface of the telescopic tube, resting within its Ys, with
the bubble of its level at the reversing point.

Support for the Sector.—A block of compact micaceous sand-
stone, (estimated to weigh two tons and a half,) hewn, with
trifling waste of the material, into a pillar nine feet long, and
of the average diameter of two feet, was set up, at the bottom
of a pit four feet and a half deep, with its thicker end based
on bedded rock. ‘The excavation being gradually filled up
with earth well rammed down, the pillar became so firmly
fixed, that no change of situation of the observer, nor appli-
cation of his utmost force against its sides, affected its inclina-
tion more than a fraction of asecond. After a lapse of some
days (extremely variable in the temperature), the top of the
pillar was worked as even and as horizontal as practicable.

Three cylinders of lead, each three inches in diameter and
nearly an inch thick, introduced within the lower part of the
frame of the sector, served effectually to keep it steadily in its
place upon the pillar.

Description of the Proof-Level.—The level tube, made to
order by the celebrated Fortin of Paris, is twelve inches long,
one inch in external diameter, but considerably less within,
the sides (to prevent flexure) being so thick as to require some
care in reading off the divisions without parallax. Each end
of the tube is cemented intoa brass socket or hollow cylinder
one inch and a half in length. ‘The scale contains 230 divi-
sions, of one millimetre each, etched on the glass and stained
red, each division being equal to little more than half a se-
cond, equivalent to one sixteenth of an inch for one second.

The frame of the level was a well-squared bar of mahogany
full 17 inches long, 1°5 broad, and 2 inches deep (or high).
At equal distances from the ends two horizontal brass plates
2 of an inch long, 4 of an inch thick, and nearly of the breadth
of the bar were fastened to its upper surface by two strong
screws. For the support to Fortin’s level-tube each plate
carried a Y (formed out of the same piece of brass as the plate)
placed at a distance of 10 inches asunder, with their angular
points in a line parallel to the (vertical) sides of the frame.

A brass plate $ of an inch long, 4 of an inch thick, and of the
breadth of the frame was secured to each end of its under surface
by four long screws driven in nearly at the corners of, and
level with* the plates. These plates (previously attached to the
frame) were ground to a true plane upon two} contiguous

* In the measurements no part of the screw-heads would come in con-
tact with the cylindrical rings of the sector.
+ The diameter of neither plate being equal to the length of the bar.

N.S. Vol. 10. No. 56. Aug. 1831. N iron.

90 Mr. Nixon on the Measurement of the

iron (?) surfaces (used in grinding the receivers of air-pumps),
fixed parallel to the horizon and level with each other by
means of an adjusted spirit-level.

A few trials with the proof-level indicated that the cylin-
drical ring of the sector the nearest to the object-glass was
slightly conical; for although the proof-level had but little
play between the shoulders of the two rings, yet the nearer it
was moved towards the eye-end shoulder the greater the de-
viation of the bubble in the opposite direction; the total range
being about four seconds.

To obviate this cause of inaccuracy, a long smooth hone
having an even surface was fixed upon a table, and at one
end of the hone was secured, in a line with it, a board rising
some little above the level of the hone. Hence by drawing
the proof-level to and fro, and always in one direction, with
one plate on the well-oiled hone* and the other on the board,
the outer end of each plate was ground down at one and the
same angle. To reduce the inward ends of the plates the
hone was equally raised above the ’
level of the board. The plates were Be eae
now of the figure in the margin, so
much only of the original surface
being left as would come in contact with the cylindrical rings
of the sector exactly over their Ys.

To each side of the frame, at an equal distance from the end
of it, was attached an upright piece of wood, both pieces being
notched above for the reception of a level-tube furnished with
a divided scale of about 4, th of an inch to 2”. This cross
level, which served to set the brass plates transversely level,
was adjusted in the following manner. A brass bar, 20 inches
long, 4 inches broad, and } an inch thick (including the
rim), professedly ground to an even surface, was placed upon
the stone pillar and secured at the corners by four heavy
weichts. The bar being of uniform thickness and the top of
the pillar nearly horizontal, the proof-level could be placed
with its ground plates in contact with the upper surface of
the bar and reversed in direction without displacing the bubble
of the cross level beyond the limits of its scale. Hence the
plates would be horizontal in a ¢ransverse direction when the
middle of the bubble stood at a point of the scale equal to the
mean of the readings before and after reversing the frame.

The brass bar, although certainly not perfectly even, could

* To prevent the plates being durred in the operation the hone was
constantly supplied with oil, and no other force applied than the weight of
the bar.

not

tnstrumental Error of his Horizon-Sector. 91

not be more than 1’ or 2’ out of plane; a quantity too small
to vitiate the measurements *.

Measurement of the equivalent angle of the divisions of the
level scales.

1. Sector levels.—The sector was placed upon the pillar
in the shade, weighted, and the bubble of the cross level brought
to its mark. When the sector had acquired the temperature
of the air, (noted by a thermometer placed close to the pillar,)
the zero of the index carrying the level then uppermost was
made coincident with that of its arc. With the nut of the
stand the bubble was brought nearly to the beginning of the
scale, (numbered onwards from the eye-piece towards the ob-
ject-glass,) and by-and-by noted and registered for both ends
in one column A. With the nut of the zndez the latter was
moved until the bubble had run nearly to the object-end of
the scale, and its ends, perfectly stationary, registered in another
column B. ‘This process forms one observation. Secondly,
with the nut of the stand the bubble was again brought towards
the eye-end, and by the nut of the index afterwards moved
towards the object-end of the scale. ‘This constituted the se-
cond observation. When five observations were completed,
the total arc was read off without disturbing the instrument,
and the process repeated up to about ten observations, when
the final arc was read off. Half the difference between the
sum of the column A and that of the column B is the de-
grees of the scale answering to the arc last read off, and di-
viding the latter by the above difference we obtain the value
in seconds of one division of the scale. ‘This value we can
confirm by the arc first read off and the difference of the two
columns up to the time of reading off. ‘The results are sub-
joined.

Right-hand Index Level.
March 6th, 1880., Arc 6’ 17" 19° =1'74 |'Temp. 86°5
fi 1°76 36

Left-hand Index Level.
Mintch . ...°-1880; | Arc* 7!) 5! 19.<3.1"98 ="Pemp. 48°

8 0 1°91 <9.—, 40

April 14th, 1830. 10 38 1:96 — 60
May Aepimdyers« 8 23 1:39 — 68
6 32 1:90 — 67

* Admitting the rings of the sector to form together the frustum of a
cone of which the axis (during the measurements) is inclined 16” and the
upper surface 28", the error (minus) introduced by an inaccuracy of adjust-
ment of the cross level amounting to 10’, would be equal to (28—16) =
12” x versed sine of 10’; or to 000005,

N2 Tn

92 Mr. Nixon on the Measurement of the

In most of the measurements the range of the bubble was
confined between points of their scales made use of in the
subsequent operations, but the result was not materially dif-
ferent from that obtained by trials on nearly the whole extent
of the scales.

Fortin’s Level.—The value of its divisions was variously
ascertained: Ist, Precisely as just described, the tube being
laid upon the under surface of the horizontal bar of one index
of the sector ; to which it was attached, in one case by a string,
and in another by a little glue.—It was fixed parallel to the
telescope of the sector with the surface of the fluid within the
tube equally bisected longitudinally by the line passing through
the middle of its divisions. (When transferred to the proof-
frame, (the cross-level of the latter being at its mark,) before
the tube was fastened within its Ys, it was made to have
the surface of the contained fluid bisected as just described.)
Another method of finding the value of the divisions when
the tube was attached to the proof-frame, was to place it upon
the rings of the sector, and compare the run of its bubble at
different variations of inclination of the sector, with that of
the levels of the latter. This method is free from every ob-
jection to which the other is liable, except that of regulating
a large instrument by a smaller and inferior one. ‘The re-
sults were as follows :

March 5th, 1830. Fortin’s level-tube attached by strings
to index bar of sector.

Are 30765 1° ==0"60. (Temp. 45°
Sed: dl 0) "60 — 43

April 1830. The level-frame fastened at its ends, by rib-
bons, to the cylindrical rings of the sector, and compared with
the right-hand level of the latter ;

AC: cossks seuss) BE Op Pv emp, 75
April 1830. The frame glued to the inside of the vertical
arches of the sector, and compared with the left-hand level
of the latter;
PAR GES weak 1° = 0/63: \ Temp: (52°
April 1830. The brass sockets of the level glued to the
index bar of the sector, and a ribbon passed tightly over the
middle of the glass tube and the index-bar. ‘The run of the
bubble amounted to 1721 divisions.

Are Egy T= "60" “Temp. 60°
April 1830. Repeated with the ribbon cut off, which caused
the bubble to run immediately exactly 1/’, from one end towards
the middle of the tube. The result was unsatisfactory, yes
the

instrumental Error of his Horizon-Sector. 93

the great discordance between the values by the first and se-
cond arcs,
Arc 10/29% 1°=0"'"65 Temp. 60°.

April 1830. Same as last, but the final arc only was
read off.

Arc 9/337 1° =0”65 ‘Temp. 60°.

The experiments on levels differently mounted (given in Phil.
Mag.and Annals, vol. v.), led me to anticipate some of the above
discordances. Probably they were increased by the weight of
Fortin’s level-tube, which might be sufficient, when resting
upon the index-bar (which has no apparatus to clamp it to its
arc), to depress it gradually. On this account it would have
been advisable to have made two sets of observations, one
with the telescope elevated, and the other with it depressed.
In the former case the weight of the tube would tend to give
an arc in excess, and in the latter case in defect.

(In reply to my inquiries, M. Fortin informed me that he
had not ascertained the value of the scale with extreme exact-
ness, but that the divisions would be about half-a-second sez-
agesimal each.)

Process of measuring the horizontal inclination of the cylinder.

There are three methods. One is, to place the upper sur-
face of the (supposed) cylinder exactly parallel to the horizon
by means of the; proof-level, and then to take it out of its Ys
and replace it within them reversed in direction; the conse-
quent deviation of the bubble of the sector-level being double
the horizontal inclination. Or, if we have previously deter-
mined the reversing point of the sector-level, the difference
between that point and the one at which the bubble stands
when the surface of the cylinder has been rendered horizontal
by the proof-level, gives, without reversion of the cylinder,
the inclination required. In this method it is not necessary
that the proof-level should be strictly parallel to the cylinder,
or its plates truly horizontal in the transverse direction ; but,
onthe other hand, we measure the inclination by the sector-
levels which are inferior to that of Fortin. As it is almost
impossible to place the cylinder with its upper surface hori-
zontal to the fraction of a second, it must be noted which end
of the cylinder stood the highest, and the amount, in the case
of the thicker end, must be apt aed from the measurement.

Every visible particle of dust being carefully removed from
the cylinder and the Ys, the proof-level was placed upon the
gard with one side of the bar resting within and against
the adjacent are of the sector, and the opposite side of the bar

against

94 Mr. Nixon on the Measurement of the

against the other arc*. ‘The cross-level of the sector being
exactly, and that of the proof-level nearly at their respective
marks, the latter was rendered perfectly so (a little at the ex-
pense of the sector cross-level) by moving the arcs a second
or so out of a vertical plane. ‘The proof-level and that of
the sector being read off, the former was replaced reversed
in direction, and read off, and finally, the cylinder being re-
versed within its Ys, the sector-level uppermost was read off,
but not before the proof-level had been replaced, as its weight
was found to alter the sector-level about 1".—The process
was then repeated, on the opposite surface of the cylinder,
with the other level of the sector. In these observations it was
always noted whether the telescope pointed north or south,
and the readings for all the levels were registered in two co-
lumns, one for the north ends, and the other for the south
ends of their bubbles.

The conical figure of the object-end ring of the sector has
already been pointed out. With the reduced piates the proof-
level could, however, be pushed close to the shoulder of either
ring without causing a deviation of more than half-a-second
in Fortin’s level. In reversing the sector the effect of the
conical ring would be even more insignificant; the play within
the Ys being scarcely perceptible.

The measurements with the reduced plates were made,
April 13th, 1830; Fortin’s level tube being secured within
the Ys of the frame by broad ribbon passed round the sockets
of the tube and the frame, and made perfectly tight by stitch-
ing together the ends of the ribbon with strong thread.—On
placing the eye in the plane of the horizontal plates of the
proof-level, their contact with the surface of the cylinder was
so uninterrupted, that scarcely a glimmering of light could be
seen ‘anywhere between. The temperature being 49°, the
horizontal inclination appeared to be 31"°1 by the right-hand
level, and 29"2 by the other; mean 30""15. ‘The discrepancy
may arise from that surface of the eye-end ring, which is
uppermost when the right-hand level is made use of being
slightly corroded; or partly because the scales of the two
levels have not had their angular equivalents determined with
equal accuracy.

Second Method.—The cylinder being placed within its Ys
with the bubble of its level at the reversing point, the incli-
nation is found by placing the proof-level upon it direct and
reversed; half the run of the bubble giving the inclination re-
quired.

In this method, especially when the cylindrical error is con-

* The arcs are not exactly parallel to each other. .
siderable,

bs

instrumental Error of his Horizon-Sector. 95

siderable, some care is required in keeping the plates hori-
zontal in the transverse direction, and in making the proof-
level parallel to the cylinder; both sources of error tending
to give a measurement in defect. In some instances it was
attempted to place the proof-level parallel in direction to the
cylinder, by bringing the middle of each end of the former to
the highest point of the adjoining shoulder of the latter; the
bar being prevented from toppling by a delicate wedge of
mahogany gradually introduced between the sides and the arc
until the cross-level of the frame arrived at its mark. When
the proof-level was placed in contact with both ares (which
was more frequently the case), the deviation from parallelism
with the cylinder could not possibly amount to a tenth of a
degree,—a quantity too small to be sensible in its effect on the
measurements*.

It does not appear that there were any trials of this method
with the plates reduced, and the results of those made pre-
viously were, for the reason assigned, too discordant to be
worth transcribing.

Third Method.—This differs from the preceding one solely
in completing the measurements without reference to the levels
of the sector; the proof-level being noted, both direct and
reversed, when in contact with the cylinder before as well as
after the latter is reversed within its Ys. If the angular points
of the Ys are level with each other, the proof-level will give
the inclination of the cylinder alike before and after the latter
is reversed; otherwise, if the inclination be made too much
before, it will come out equally in defect after reversing the
cylinder +.

Fortin’s level-tube being glued at the sockets to the Ys of
the frame, the inclination of the cylinder given April 16th,
1830, temperature 58°, by the third method, was 26"-9 with
the left-hand level upwards, and 29"-1 with the other level
uppermost. On the same day, the measurements repeated at a
temperature of 56° were respectively 27-3 and 29-2; the mean
of the whole being 28""1, or 2" less than by the first method.

Multiplying the mean of the two methods by 0°586 (the Ys
opening at ‘an angle of 90°), we obtain 17-1 for the constant
error of collimation of the sector t.

* When we measure the inclination of a plane, if we do not place the
level-tube exactly at right angles to a level line drawn on the plane, we
obtain a measurement (in defect) equal (when the deviation and inclina-
tion are both small) to the correct quantity divided by the secant of the
angle of deviation.

+ By precisely the same process may be found the inclination of the
(mathematical) axis of rotation of a transit instrument having unequal
pivots. { See page 429 of last volume. ;

t

96 Mr. Nixon on the instrumental Error of his Horizon-Sector.

It is a good verification of the measurements to find the
reversing points of the proof-level the same on the cylinder
as on a plane made as nearly horizontal in every sense as pos-
sible. But it is to be remarked that unless the plates of the
proof-level are true planes, the reversing point may not be
the same on the cylinder as on the plane. For want of a per-
fect plane this satisfactory confirmation could not be obtained;
but the reversing points with the proof-level on the cylinder,
as may be seen from the statement below, agreed within the
fraction of a second of their mean value.

April 13th, 1830. Temp. 50°. Reversing point...... 105°
105
107
107

Mean 106

April, L6th, 1880... Vem, 58° pexcavegecstiaes t demaiaulas oe SS
113
113}
1142
1134
Ls
1134

Mean 1132

AprTl 16th; 4830. | Tetnp. 56° 8s sce eeie lieth tate eee
114
114
1142
1122
1122
112
1112

Mean 113}

(One division is equal to about half a second.)

There is this serious objection to all the three methods, at
least in their application to the sector,—that the inclination of
the cylinder cannot be measured on that part of its surface
which comes in contact with the Ys during the process of ad-

justing the instrument.
(To be continued. |

IX. Notes

[ 97 ]

1X. Notes on some recent Improvements of the Steain-Engines
in Cornwall. By W.Jory Henwoop, F.G.S. Member of
the Royal Geological Society of Cornwall.

To Richard Taylor, Esq. F.S.A. F.LS. Sc.
Dear Sir,

HE same excuse which was offered by Mr. Farey for his

long silence on the subject of my paper* may, perhaps,
now serve for mine on that of hist. I shall not attempt a
regular discussion of his papers, as the digressions and the
many objects they embrace, would, ! fear, be unsuitable to
your pages, and tiresome to your readers. I purpose confining
myself to the various alterations and improvements which
have been made in this county since Messrs. Boulton and
Watt, and their agents, ceased to superintend the steam-
engines on our mines; with the addition of a few incidental
observations on some of Mr. Farey’s statements.

In my former communication to you on this subject, I said
that “variation in the elasticity of the steam employed by
no means affects the invention [my views would have been
more correctly expressed, had I said the merit or principle of
the invention | of expansive working ;? and, notwithstanding
Mr. Farey’s indignant attempts, he has advanced nothing
which bears the semblance of proof of the contrary.

‘Mr, Farey says{, Mr, Watt “ proposed in 1782 to work
his engines by stopping the supply of steam when the piston
had only moved one-fourth of its course.” Will that gentleman
particularize the engines in this county which now expand
more than three-fourths of their stroke? ‘ Mr. Watt’s en-
gines with such boilers” (which will not retain steam of more
than 32 pounds per square inch above the atmosphere) “ can-
not be made to exert a competent power to drain deep mines,
unless the supply of steam to the cylinder is continued until the
piston has run through more than half its course {.” This
I humbly apprehend will depend on the size of the engine,
and the weight to be lifted, I hope I shall not be charged
with ‘‘altering” this sentence so as to make it ** very indefinite.”

In 1801-2, Captain Trevithick erected a high-pressure
engine of small size at Marazion, which was worked by steam
of at least 30 pounds: on the square inch above atmospheric
pressure. In 1804, as Mr. Farey admits §, the same gentle-
man introduced his celebrated and valuable wrought-iron

* Phil. Mag. and Annals, N.S. vol. vii. p. 323.
+ Ibid. p. 421, and vol. viii. p. 305. t Ibid. p. 309.
§ Ibid. p. 313.
N.S. Vol. 10. No. 56, Aug, 1831. O cylindri-

98 Mr. W. J. Henwood’s Notes on some recent Improvements

cylindricai boilers*, now universally used in this county. To
these, every one at all acquainted with the Cornish improve-
ments ascribes a great part of the saving we have obtained.
This will further appear from an extract from a valuable work
edited by John Taylor, Esq. F.R.S.+: the monthly con-

sumption of coal in Dolcoath mine was in

“1807, 5112 ee and the mine eee 160 fath. level under
} being sunk below the §adit: adit 42 f. deep.
1808, 5184 ———— S—&s —___— 170 fathom level.
1809, 5688 ———— ————
1810, 6840 ———— ————_— 180 fathom level.
1S Ad Okey ee Sete eee
1812t,4752. —————- _- ———__- 190 fathom level.
ISI WS) SS SS

1814, 5413 ek
TSR) es ee eae ates
1816§,6826 9 pena
1817, 3102 a) ea a

The alteration in the boilers, was the introduction of Capt.
Trevithick’s cylindrical boilers in place of the common waggon
boilers, which had until then been there in use.

In 1811-12, Capt. Trevithick erected a single acting en-
gine of 25-inches cylinder, working with but two valves (the
exhausting valve being wanting) at Huel Prosper Mine in
the parish of Gwithian, which of course had a cylindrical
boiler, in which the pressure of steam was more than 40
pounds on the square inch above atmospheric pressure; and
the engine was so loaded that it worked full seven-eighths of
the stroke expansively. Mr. Woolf, as Mr. Farey states ||,
came to reside in Cornwall about the year 1813, and his “ first
engines for pumping water from mines were set up by him in
1814, at Wheal Abraham and at Wheal Vor mines in Corn-
wall; they had each two cylinders.”

If the use of high-pressure steam acting expansively were
a part of Mr. Woolf’s patent, to which he could establish a
legal and exclusive right; why did he not prefer a claim on
Capt. Trevithick, or the adventurers in Huel Prosper Mine,
who were using an engine of that description before that gen-
tleman’s arrival in Cornwall? The answer is obvious. Mr.
Taylor remarks 4, “ During the whole of this year (1814),

* Phil. Mag. and Annals, N.S. vol. i. p. 127. + Records of Mining,
p- 163. { Alteration in the boilers this year.

§ In this year the old engine was replaced by a new one ;—of this more
hereafter. || Phil. Mag, and Annals, vol. viii. p. 308.

4 Records of Mining, p. 156.

Jeffery

of the Steam-Engines in Cornwall. 99

Jeffery and Gribble’s engine at Stray Park performed the best
duty, being the first that reached 35 millions, and maintain-
ing for twelve months an average rate of $2 millions. Woolf’s
engine at Wheal Abraham was first reported in October in this
year, and performed 34 millions. Number of engines reported,
29; average duty, 20,534,232.” In the early part of 1816,
a single engine of 76-inch cylinder was erected at Dolcoath
mine by Messrs. Jeffree and Gribble (see preceding note), in
place of an old and defective double one; which accounts for
the diminished consumption of coal which the extract from Mr.
Taylor’s notice of Dolcoath exhibits. In the same year Mr.
Woolf replaced an old engine of 63-inch cylinder, but which
had for a short time previously been worked by higher steam
than usual, with one of 66-inch cylinder at Huel Abraham:
the latter, if I am not mistaken, was set to work about the
12th of November.

I believe I have now satisfactorily shown that Mr. Woolf,
instead of being the first to introduce the expansive action of
steam in one cylinder, was positively preceded several years
by Capt. Trevithick, and probably so, a short time, by Messrs.
Jeffree and Gribble. Mr. Farey says, ‘‘ He” (Mr. Woolf)
“altered another old engine at Wheal Unity, by adding a
small cylinder to it; the performance was improved in about
the same degree as that of the old engine with one cylinder *.”
Perhaps Mr. Farey may not be aware that after being altered
the Huel Unity engine did not answer expectation, and the
nossels which Mr. Woolf had put in were thrown out and
replaced by others; this only made the matter worse, for the
engine would not then keep the water (‘zm fork”); to remedy
the defect these were removed, and those first put in were re-
placed. But, to mend the matter, for several years before the
engine was stopped, the use of the small cylinder was dis-
pensed with, and the engine worked as a common Watt’s
single engine; in which mode it is at present worked on Oppie’s
shaft in Poldice mine.

Whilst on the subject of alterations, I may remark that
Mr. Woolf had intended adding a small cylinder to the old
engine (48-inch cylinder, single) at Huel Vor but the un-
toward result of his experiment at Huel Unity, prevented his
making the attempt, although a cylinder was purchased for
the purpose. This was subsequently, after much labour in
enlarging the apertures, used by Messrs. Jeffree and Gribble
as onlinder for a small double acting rotatory engine erected
to move a stamping apparatus on the same mine, where it is

* Phil. Mag. and Annals, N.S. vol. viii. p. 312,
O02 still

100 Mr. W. J. Henwood’s Notes on some recent Improvements

still at work. Mr. Farey continues *, ‘ In a short time after
Mr. Woolf’s patent expired, most of the old Boulton and
Watt’s engines in Cornwall were altered to work by high-
pressure steam on his system: some few had an extra cylinder
added.” Instead of the pressure of steam in general use being
raised at that period, I assert no such alteration took place
in a more marked degree, then, than had before obtained ;
and the alteration which at all took place was not in conse-
quence of Mr. Woolf’s assertions or performances, but of those
of Capt.Trevithick. Will Mr. Farey name an engine to which
a cylinder was added (that it might be worked on what he calls
Mr. Woolf’s system) after the expiration of that patent? He
proceeds}, ‘* The advantage of the change from low-pressure
to high-pressure steam, on Mr. Woolf’s system, was manifest
in all cases; but it was greater or less, according as the steam
was used stronger and with more or less expansive action.”
Now, I maintain that there is not a shadow of ground for this
assertion, and I challenge Mr. Farey to prove its accuracy.
He says, ** Previous to 1826 the steam cases were not clothed,
but exposed to the air.” That the steam cases of Boulton
and Watt’s engines were covered with lath and plaster whited
on the outside, is notorious; their steam pipes were also
encircled with straw ropes plastered and whited. ‘The steam
case at Dolcoath engine was surrounded with a casing of sheet-
iron ; the interval of about four inches being filled with straw,
hemp, saw-dust, and other imperfect conductors of heat.
Mr. Farey says §, “ Mr. Hornblower, who practised that sy-
stem” (expansive working) “‘in two cylinders, did not suc-
ceed so well as Mr. Watt himself, who only used one cylin-
der.” I repeat, that “ variation of the elasticity of steam em-
ployed by no means affects the principle of the invention ;”
the superiority of one cylinder over two being proved with
low-pressure steam, it appears to me “ignorance in spite of
experience” to expect a contradictory result by variation of
tension only; and, still stumbling over the results of his own
experiments as well as those of Messrs. Watt and Horn-
blower, Mr. Woolf’s engine with two cylinders at Huel Al-
fred was a signal failure.

The improvements which came prominently into notice in
1827 were commenced by Capt. Grose, at Huel Hope mine
in Gwinear parish, in 1825. They do not in any part consist,
as Mr. Farey states||, in ‘ using better boilers ;” for they are

* Phil. Mag. and Annals, N.S. vol. viii. p. 312. + Ibid.
{ Ibid, p. 312-313. § Ibid. p. 312, note. \| Ibid. 313.

precisely

of the Steam-Engines in Cornwall. 101

precisely similar to those which he before says* were “ first
brought into use for high pressure steam by Mr. 'Trevithick
in 1804;” but in different arrangement of the flues+ round
them; first introduced at Huel Hope, afterwards at Huel
Towan, and subsequently in many other mines (the Consoli-
dated, Huel Vor, &c.); in some degree by more attention to the
temperature of the hot well; and in a great proportion by
carefully covering all the vessels containing dense steam with
bodies which transmit heat very slowly.

That these originated with Capt. Grose, and were borrowed
from him (without acknowledgement) by Mr. Woolf and others,
will appear from the following extracts from Messrs. Lean’s
monthly reports.

Huel Vor Mine.
Trelawny’s Engine.
Sims and Richards,
Engineers. ||

lHnel Towan Mine.| Consolidated Mines.
Wilson’s Enginef. Best Engine.§ .
rine Grose, Engineer. Woolf, Engineer.

43-5 millions.
43-1

Jan. 48-9 millions. |Taylor’s 42-8 millions.
Feb. 518 —— Ditto 48-5 ——

March} 53:55 —— Huel Fortune41-9 —— 45-2) =
April 61-8 —— Ditto 44-] —— Ajo
May 60-6 —— Ditto 43-9 —— 46-9 ——
June 61-7 —— Pearce’s 42-7 —— 49-1] ——
July 62:2 —— HuelFortune40-8 —— 45-5 —
Aug. 61-7 —-- Pearce’s 43-2 —— 50-8 ——
Sept. | 60:1 —— Huel Fortune42-5 —— 50- = ——
Oct. 61-3 — Woolf's 63-7 —— 47-83 =——
Nov. 56-1 —— Ditto 67 —— ee nee

Dec. 57-7 Ditto 62-4**—_—

Millions.
1827: average of all the pumping engines reported 31-9

Huel Towan, Wilson’s engine ...... 58°1
—— Consolidated Mines, 12 hahaa:
; . 48°6
average of best engine ......
re - Woolf’s engine ¥ eee eeeeee ees ereeeeeee 64:4
—— Huel Vor Trelawny’s engine......... 47°2

* Phil. Mag. and Annals, N.S. vol. viii. p. 313, note.

+ Brewster’s Journal, vol. ix. p. 159.

{ Wilson’s engine was at that time the best on Huel Towan.

§ In the first nine months; the same engine was not every month the
best.

|| Trelawny’s engine is the best on Huel Vor.

§ Woolf’s engine was not reported until October 1827.

** At an experiment made by some Cornish engineers in this month the
duty was 63°6 millions,

1828.

102 Mr.W. J. Henwood’s Notes on some recent Improvements

Huel Towan Mine.| Consolidated Mines. Huel Vor Mine.

: Sas | : Trelawny’s i
1828, | Wilson’s Engine. | Woclt’s Engine. Sims and be
as Grose, Engineer. | Woolf, Engineer.* Enci f
ngineers.

not reported.t
76:1

75:8
81-9
81-6
77°8

2

74
73-6

METTLE

Millions.

1828: average of all the pumping engines reported 37:2
Huel Towan, Wilson’s engine... 77:2
ee Consolid. Mines, Woolf’s engine 62°5
Huel Vor, Trelawny’s engine...... 55°

I think the foregoing details prove, not only that Captain
Grose led the van of the more recent improvements, but that
he has kept far in advance of its strides. The importance of
the saving thus obtained cannot be more plainly shown than
by the following extract from Mr. Taylor’s valuable “ Re-
cords” t. ** In 1825, all the drainage of the Consolidated Mines
was effected by three engines only; they were hard pressed
by the increased depth of the mine and quantity of water, and
derangement happened, which, added to the bad state of some
boilers, and the pit-work, which suffered from the engines
being unavoidably worked too fast, the duty of the engines
fell off considerably, and, as the reports will show, did not
average quite 30 millions; at that time the monthly consump-
tion was

Job’s engine (90-inch cylinder) 4992 bushels.

Pearce’s do. (58 do. ) 3615 ——
Bawden’sdo. (90 do. ) 8427 ——
17034

s* At the present time (1829) six engines are at work, as,
to remedy the evils above stated, and to provide for sinking

* For all 1828, it took the lead of the Consols’. engines.

+ In this month an experiment was made by Cornish engineers, duty
87-2 millions; and in April 1830 by Mr. Rennie and myself, duty
92,260,202 by calculation, and by waler delivered as determined by a float
83,602,022.

t+ Records of Mining, p. 164.

deeper

of the Steam-Engines in Cornwall. 103

deeper, three additional ones have been erected, and the con-
sumption of fuel now stands as under, the mines being 20
fathoms deeper than in 1825:
Job’s engine (90-inch cylinder) about 2050 bushels.
Pearce’s do. (65 do. \(altered)2130 ——
Bawden’s do. (90 do. ) about 2050 ——

Taylor’s do. (70 do. ) 1480 ——

Woolf’s do. (90 do. ) 1710 ——

Shears’s do. (70 do. ) 1180 ——
10,600

« The average duty of the six engines is now reported at
more than 50 millions.” This difference I attribute entirely
to Capt. Grose’s improvements. Mr. Farey has thought fit to
charge me* with keeping back the fact of our engines having
only one cylinder, and being worked with high-pressure steam,
acting expansively. If he will refer to Brewster’s Journal,
vol. ix. p. 160, and vol. x. p. 42, he will find papers (which
although inaccurate in some minor details are substantially
correct) in which the elasticity of the steam employed is_par-
ticularly mentioned. He has also said that I have, in quoting,
“altered” his expressions, so as to make them “ very inde-
finite’ +. I believe my quotations present his ideas in quite as
definite a form as that in which they stand in the original;
and I do not base this assertion on my own opinion only.

I may now be asked, in what respect Mr. Woolf has been
a benefactor to Cornwall? I reply, In introducing accurate
workmanship and some attention to proportion in the con-
struction of engines, both which disappeared on Messrs. Boul-
ton and Watt’s removal. These I take to be the only benefits
he has conferred on the county; but they are favours of no
mean order, as those who know the state of the engines in
Cornwall, before his arrival in the county, will readily admit.

I pass over some points of minor importance on which
I could have desired to make a remark or two, as I fear I have
already trespassed too long on your -patience, and I am half
ashamed that the discussion has assumed so unconnected a
form; but however much I may be disposed to enter further
upon it, I shall deny myself the honour, unless the inquiry be
in future directed to but one point at a time. Yours, &c.

Perran Wharf, near Truro, Ww. J. Henwoon.
April 11, 1831.

» Phil. Mag, and Annals, N.S. vol. vii. p. 423. + Ibid. p. 422.

X. On

[ 104 ]

X. On Chemical Symbols and Notation; in Reply to Pro-
essor WuHEwELL. By Mr. Joun Pripreaux, Member of
the Plymouth Institution.

To the Editors of the Philosophical Magazine and Annals.
Gentlemen,

N the last Number (May 1831) of the Journal of the Royal
Institution, is an article by Professor Whewell, “ On the
employment of Notation in Chemistry ;” going to show the
advantages of using symbols in that science; and to remove
anomalies in the foreign notation, by reducing it to mathema-
tical consistency and symmetry. I concur with all that is
therein stated of the practical convenience and utility of such
symbols, and I am glad to see Professor Whewell’s eminent
name enlisted in their advocacy. ‘They constitute a prompt,
impressive and peculiarly legible short-hand ; expressing in a
few letters and dots what would occupy several lines of writing,
and what no writing will give with the same distinctness,—
a great point in a science of which the materials and modifi-
cations are so numerous and so complex. In experimental
notes they are of great service, placing constantly before our
eyes the entire analysis of every material employed; and for
the same reason, as well as on account of their compactness,
are aptly suited for comparison and tabular classification. But
I am not yet convinced that it is desirable to sacrifice this
graphic simplicity, in order to convert them into an algebraic
notation; to which, when requisite, they are easily accommo-
dated. Such of your readers as feel interested in this question,
and have not seen Professor Whewell’s paper, would do well
to read it before proceeding with this.

The chemical symbols of Berzelius were contrived ‘ pour
faciliter expression des proportions chimiques, et de nous
mettre en état d’enoncer briévement et avec facilité le nombre
d’atémes élémentaires qui se trouve dans chaque corps com-
posé.” ‘To this purpose they seem happily fitted; exhibiting,
in signs no less natural than compact, the entire constitution
of the substance through all the grades of analysis.

Thus an atom of potassium, K (/alium in Berzelius’s Latin),

oxidized with one atom oxygen K, forms potash; an atom of
nitrogen N, with five atoms oxygen N, forms nitric acid, and

K N forms nitrate of potash.

In this concise symbol we see the acid and alkali, and the
elementary composition of each: the bases expressed in their
initial letters; and oxygen, the great modifier of chemical

properties ;

Mr. J. Prideaux on Chemical Symbols and Notation. 105

properties,—the pivot, as it were, round which chemical agency
revolves,—is exhibited, in a manner equally characteristic, pro-
minent and compact, by dots, corresponding to the number of
atoms placed over the symbol.

Again, H is hydrogen; H* three hydrogen; and NH? am-
monia. C is carbon, C*? two carbon; and C*N cyanogen.
HC°N is hydrocyanic acid; and NH*HC?°N hydrocyanate of

ammonia.
Al is aluminum; Al alumina; S sulphur; Ss sulphuric

acid; and AIS sulphate of alumina. A compound salt is
expressed by joining its proximate ingredients through the

sign +; thus Al S+NEBS is sulphate of alumina and am-
monia. When one Of the constituents is in more than one
atomic proportion, it is preceded by the indicatory multiple :

thus NH?S+3 Al S is ammoniacal alum, which crystallized

with 25 atoms water becomes NH? S+3AI1S+ Ag*.
(It is my custom to write the salifiable bases in inclined,

and the acids in erect letters, NH°S+3Al S+ Aq, which is
attended with some conveniences; but has not received the
sanction of Berzelius, and might, though in my practice it
has not so occurred, possibly interfere with his mineralogical
symbols.)

A principal objection, in the paper above quoted, is, that
the symbols are joined in the way which, in algebra, denotes
multiplication.

But this juxta-position KN, and the employment of an
index figure, NH?, as practised by Berzelius, lead the chemist
into no error, because their subjects are not susceptible of
algebraic powers, or of being multiplied into each other. We
can have neither cube nor square of H (hydrogen), nor ob-

tain a multiple of K by N: and the cases in which atomic
calculation would necessarily generate such products are so
rare that the letters x, y, &c. may be substituted, or the actual
symbols adapted to the occasion; without general destruction
of their conciseness, by multiplication of signs, brackets and
letters. Chemical mathematics are mostly simple, but a dif-
ference is to be made in the symbols, according to the more
or less compound character of the individual subjects of cal-
culation. If simple bodies were concerned in the process, we
should represent them as 0, oxygen; c¢, carbon, &c. If
alkalies and acids, as potash, nitric acid, &c. we should state
them /,n; or C, n’, if preferred. But with respect to tri-silicate

N.S. Vol. 10, No. 56. Aug. 1831. iy of

106 Mr. J. Prideaux on Chemical Symbols and Notation ;

of alumina, sulphuret of iron, arseniuret of cobalt, &c., we
should employ a single letter for each, unless their decompo-
sition were concerned in the research. In short, however
contrived, they must be variable and varied, as in other sci-
ences, for algebraic adaptation; and they would be analytical
so far only, as decomposition is connected with the calculation,
as will be exemplified below.

Although juxta-position implies multiplication in algebra,
the signification is arbitrary; and in another science, equally
mathematical, with elements susceptible of every mathematical
power, we can so place them without fear of understanding
CLV as Cx LxV, or 534 as5x3%x4. This position implies
naturally (if the word be allowable) the meaning Berzelius
attaches to it, alliance or combination; the truth of which is
illustrated in the paper under review; in which one of the
ablest algebraists of the age, in the very act of publicly ar-
raigning it, writes

Protoxide of manganese mn + 0 Mn
Sesquioxide .........00000 mn + 30 Mus
Dentoxidetes..i..s23085..) mn 20 Mann

and by the same rule would write the oxides of osmium,
Om Omm, Ommmm.

Two cases are quoted from Herschel, to exemplify the ad-
vantages of a more mathematical system. One describing
‘the decomposition of oxynitrate of silver by hyposulphite
of lime.”

“‘L represents lime; S, sulphur; s, silver; O, oxygen; N,
nitric acid. He says, ‘ we have for the atoms present, before
the decomposition,

{L +2(S+0)} + {N+(s+0)}
which afterwards group themselves thus :
=(L+N)+(S+s)+(S+ 30)
that is, one atom of nitrate of lime, one of sulphuret of silver,
and one of free sulphuric acid.’ ”

The other is of kindred character; and they are given as
‘“* very instructive examples of the use which may be made of
such a notation.” The system of Berzelius is said to possess
no such advantages.

Of the case quoted it may be observed, that the sign + al-
ternates with every letter, whether indicative of intimate com-
bination, mixture or decomposition; and that an incompatible
mixture is made = equivalent to a compatible one* :—that

* The sign = in Mr. Whewell’s paper is employed only in the second

example; but the circumstances being the same, it is needless to quote

both.
the

zn reply to Professor Whewell. 107

the symbols are severally constructed for the occasion, free
from the restrictions of any rule of intelligibility; lime, com-
posed of an atom of calcium and one of oxygen, being signified
by L; whilst oxide of silver, also of an atom of each ingre-
dient, is made (s + O): sulphuric acid, one atom sulphur and
three oxygen, is (S + 30); whilst nitric acid, of five atoms
oxygen to one nitrogen, is only N. The chemistry is in fact
sunk in the mathematics, simple as they are; and the scheme,
without the text, is totally unintelligible.

Berzelius would express it thus: Ag N with Ca 8
gives Ca N, AgS and S

Ca being lime; Ag, oxide of silver; S*, two atoms hyposul-
phurous acid, &c.

Here you have the whole process (its chemical probability
being not in question) in the symbols, as well as the proxi-
mate and ultimate analyses of each ingredient.

We may now contrast the proposed notation with the ex-
amples before given of the symbols.

Berzelius. Whewell.
Nitrate of potash KN (k+0)+(n+5 0)
Hydrocyanate STI CON rarer
yd Heisitnia NH*HCN (n-4+3h)+(a4+20+h)
Ammoniacal, 341 S4NWS {Salpotst3q}+G+a-+s 40)
Do. contracted.
Nitrate of potash ......cesesseseees K+n/
Hydrocyanate of ammonia...... Am+thedn
Ammoniacal alum. .......sseeeees (3 Al+s/)+(Am-+s’)

The multiplication of lines and brackets in the proposed
notation gives it, in my view, a comparatively perplexed ap-
pearance, though algebraically just. ‘The unvarying sign +
alternating with every letter, loses the distinctive property, in
which consists its value. ‘The increased length of the formula
destroys its graphic character: and in the contracted notation
this graphic property and the analytical expression are both
incomplete.

To apply this notation in the case quoted from Herschel,

{(c +0) + 2(s + 0)} + {(n + 50) + (ag + 0)}
={(c+0) + (n+ 50)! +(s + ag) + (s + 30).
or, contracted, (C + 2s’) + (Ag + n’)
=(C +n’) + (Agt+s) +5.
Here the full notation appears confused by the needless
P2 multiplicity

108 Mr. J. Prideaux on Chemical Symbols and Notation.

multiplicity of terms, &c.: the contracted does not apply; but
both together will do very well. This simple case, then, amply
illustrates the need of varying the structure of our symbols
according to the occasion, when employed mathematically.
The chief objection made to the mineralogical signs of Ber-
zelius is, that “ the analysisitself is not recorded” by them.
But here would seem to be some misunderstanding. Their
difference from his chemical symbols is, that they do express
the result of analysis only, apart from atomic relations; the let-
ters signifying merely the names; and the figures giving the
relative quantities of the common ingredient, oxygen; and, by
consequence, the constituents, from the known proportions
in which they contain it. Thus apophyllite is given by Ber-
zelius, (Nouveau Systeme de Minéralogie, p.225,) KS®+8 CS i
+16 Aq: recording, that the oxygen in the lime is 8 times ;
in the silica, 6+8 x 3 = 30 times; and in the water, 16 times
that in the potash: whence the respective ingredients may be

read off, on the scale of equivalents, K 5°95; Ca, 28°25;

Si, 60; Ag, 18. And the cases quoted at p. 449 of Professor
Whewell’s paper are rather equivalent than identical.
Berzelius employs these signs in mineralogy, because “ quant
aux formules chimiques, elles sont sujettes 4 changer d’aprés
des changemens dans nos idées du nombre des atomes élé-
mentaires dont chaque substance est composé.” Nouv. Syst. 190.
This is exemplified in the change of some of his own views
since that treatise was written. He would then have construed

the above formula, chemically, thus: K Si*+8 Ca Si?+ 32 Ag.
Now he regards potash and lime as each containing a single

atom of oxygen; and the chemical formula would be K Si?

+ 8CaSi + 16 4q; or without grouping K +8Ca+ 10Si
+16Aq; the proportions being still preserved. And hence
these signs seem peculiarly adapted to the purpose of minera-
logical record.

The mineralogical notation proposed in the article quoted,
would require a local and chronological date to every re-
corded analysis, or would involve them in the hypothetical
changes of atomic chemistry. Had the above analysis of
apophyllite been so stated, the quantities of lime and potash
would have been reduced one half by the publication of
Berzelius’s last atomic table; and the silica would have been
reduced two thirds by the formula being reprinted in En-

land.
: With respect to the grouping in these formule, the vee
of

Mr. Brooke on Poonahlite and other Minerals. 109

of Professor Whewell appear to me to be just. The crystalline
form must be affected by the state of the combination; and
arbitrary or hypothetical statements may impede our attain-
ment of correct views on a subject of prime importance in
mineralogy.

But I cannot yet see the propriety of sacrificing the con-
cise and graphic perspicuity of the Berzelian symbols, for the
purpose of reducing them to a notation, perhaps not very
much more generally applicable to mathematical use; far less
so to that of temporary record and tabular comparison in
operative chemistry ; and in mineralogy of hazardous admissi-
bility. Yours, &c.

Plymouth, June 4, 1831. J. PRIDEAUX.

XI. On Poonahlite, a new Species of Mineral; on the Identity
of Zeagonite and Phillipsite, Sc. ; and other Mineralogical
Notices. By H.J. Brooke, Esq. F.R.S. L.S. 5 G.S.

To the Editors of the Philosophical Magazine and Annais.
Gentlemen,

I SEND you herewith a few mineralogical notices, which
will probably interest some of your readers.
I am yours, &c.
June 11, 1831. H. J. Brooke.

Thulite.

In a list of minerals which I published in 1823, as an Ap-
pendix to an elementary work on Crystallography, I described
this mineral as having a cleavage parallel to the planes of a
rhombic prism of 92° 30', which description was given on the
authority of some fragments of a reddish mineral received by
Mr. Heuland, from Sweden, under the name of Thulite. I since
find that the mineral I then measured was Bisilicate of man-
ganese. Ihave lately obtained and measured the true Thulite,
and have found it agree in its cleavages and angular mea-
surements with Epidote, as it had been before found to do by
Mr. Levy.

Reagonite.

In the same list of minerals I described the crystalline form
of Zeagonite as an octahedron, with a square base ; and I did
this upon the authority of a crystal from Vesuvius, so named
in the ticket by which it was accompanied. The crystal I then
measured has since been called Zircon, but whether analysed
or not I do not know. I have lately obtained specimens of
the Zeagonite described by Gismondi, which I shall probably

make

110 Mr. Brooke on Poonahlite,

make the subject of a distinct communication, having satis-
factorily ascertained that Zeagonite, Abrazite, Aricite and
Phillipsite are one and the same mineral.

Velvet Copper Ore of Werner.

On dissolving this mineral in dilute nitric acid, a skeleton
remains which is insoluble in any acid; and when the very
minute portion J had to examine was placed on charcoal before
the blowpipe with a drop of nitrate of cobalt, it ultimately be-
came black; whence I concluded it to be silica. The part dis-
solved in the dilute acid contained sulphuric acid, copper and
zinc.

Native Nickel,
so called, although a sulphuret. I have measured the fibres
of this substance, and find them regular hexagonal prisms with
apparent cleavages oblique to the axis, but the cleavage planes
are too imperfect for accurate measurement.
Poonahlite.

I am indebted to the kindness of Mr. Heuland for some
specimens of a beautiful variety of apophyllite from Poonah,
in the East Indies, accompanied by some slender crystals,
which I at first supposed were mesotype or needle-stone,
but which differ from both substances in measurement; the
Poonahlite being a rhombic prism of 92° 20'.. The crystals
traverse the mass of the apophyllite and matrix instead of
forming groups in the cavities; and among several hundred
crystals which I have examined on my own and on Mr. Heu-
land’s larger specimens, I have not observed one with a na-
tural termination. The hardness is nearly the same as that
of needle-stone, as far as I can discover from an experiment
on very small crystals.

Glaucolite.

This mineral has a cleavage parallel to the planes of a
rhombic prism of 143° 30! nearly.

Couzeranite.

This is described in Leonhard’s Handbuch, as a right rect-
angular prism, and by Dufresnoy in the Ann. de Chim. et de
Phys. xxxviii. p. 280. as an oblique rhombic prism; and it would
appear from the analysis of the latter to be a distinct species
of mineral. Mr. Heuland has lately supplied me with a spe-
cimen containing this substance in small imbedded crystals ;
on examination of which I find that it has the form, cleavage,
and angular measurements of felspar. The crystals are small,
and the matrix in which they are imbedded is partly white
and partly black. Those in the white part are colourless and

transiucent;

the identity of Zeagonite and Phillipsite, §c. 111

translucent ; those in the black part are black and opaque,
and probably coloured by the same kind of matter as colours
the matrix. Hence the analysis of the black crystals, which
are the only ones yet analysed, must fail to give the true con-
stituents of the mineral, and the theoretical chemical formula
must be incorrect. The crystals are similar in form to the
small single crystals of felspar coated with chlorite, which are
brought from St. Gothard.

Pseudomorphous Crystals from a Mine at Haytor, in Devonshire.

In the year 1827 some crystals were found in this mine,
which were described by Mr. W. Phillips and Mr. Levy, under
the name of Haytorite*. It was obvious that the substance of
the crystals was calcedony ; and as they nearly agreed in form
and angular measurement with Humboldtite, it was supposed
they might have derived their pseudomorphous character
from crystals of that substance, although from the solidity and
state of aggregation of some of the crystals which were first
discovered, it was difficult to imagine the mode by which the
borrowed forms could have been produced. It is, however,
equally difficult to comprehend the manner in which the well-
known pseudomorphous crystals of steatite, imbedded in the
same substance, could have been produced. ‘These present
the forms of quartz and of carbonate of lime, and they con-
sist of steatite apparently homogeneous with the mass in which
they are imbedded. We might indeed suppose that a cavity
partly occupied by crystals of quartz and carbonate of lime
had been filled by steatite; that subsequently the quartz and
carbonate of lime had disappeared and left moulds which were
afterwards filled by the same kind of steatite. But it is not easy
to conjecture how the mould and the casts formed at very dif-
ferent times should be homogeneous. With regard, however, to
Haytorite,there cannot now exist a doubt ofits pseudomorphous
character ; many of its crystals being hollow, sometimes very
thin, and the inner surfaces mammillated like ordinary calce-
dony. I have also a crystal of this substance which presents
a form analogous to the common hemitrope crystals of sphene
from St. Gothard, with a deep re-entering angle, and evi-
dently formed within a polished cavity which it has only par~
tially filled. But in addition to the evidences of pseudomor-
phism presented by many of the crystals of Haytorite, there
haye been found in the same mine other pseudomorphous
crystals representing several of the forms of carbonate of lime,
some of which are solid, and some hollow: among these are

* See Phil. Mag. and Annals, N.S. vol. i. p. 38, 40, 43,—Epir.
groups

112 Mr. Coddington’s Reply to Dr. Goring.

groups of very obtuse rhomboids, masses resembling pearl-
spar, acute scalene dodecahedrons, and six-sided prisms with
flat summits, or terminated by planes of the equiaxe crystal of
Haiiy ; and in one instance that lies before me, the calcedonic
cast represents one of those crystals of carbonate of lime
which are frequently observed, in which a change from a flat
to a modified termination of the hexagonal prism has only
partially taken place.

XII. On the Theories of Achromatisation, §c. in reply to Dr.
Goring. By The Rev. H. Coddington.

To the Editors of the Philosophical Magazine and Annals.
Gentlemen,

Y name having been brought before the public by Dr.
Goring, in an article contained in the last number of the
Edinburgh Journal of Science, in a manner which, though
apparently complimentary, must lead readers to consider me
as a framer of apparently fine theories, which answer no good
purpose in practice, a character for which those who know me
are well aware that I entertain very little respect, I would re-
quest leave to make a few observations in reply, through the
medium of your Journal, which I presume must find its way
wherever any scientific periodical work is taken in.

Dr. Goring states that my work on the Reflexion and Re-
fraction of Light, whether considered as a work of originality,
or as a compilation from the writings of our first opticians,
is admitted to be the best publication of the kind at present
extant. So far I am obliged to him: but in the next article
he ‘* ventures, though well aware of what he is doing, to im-
pugn the infallibility of exact science in the case of the theories
of achromatisation of Professor Robison, Professor Airy, and
Mr. Coddington, on the ground that no artist is able to make
an achromatic instrument according to them.”

Now, Sir, the plain truth of the matter is, that my work
contains, to the best of my knowledge, exactly those theories
which have guided all artists, from the elder Dollond down-
wards, who have been competent to refer to a theory at all.
To these I have added one other, (to which Dr. Goring alludes
in a note,) out of respect to its inventor Professor Airy. It is
one of singular ingenuity and beauty, and gave every promise
of a good result, but is probably imperfect, like many other
speculations of the present day, since it certainly does not
answer the end proposed. The author is well aware of this,

and

Mr. Coddington’s Reply to Dr. Goring. 113

and speaks of it, with his accustomed modesty, as of a youth-
ful production, which has at least done no harm, except, in-
deed, as it appears, exhausting Mr. Tully’s patience.

Dr. Goring, confessing that he cannot discover the least
flaw in our theories, proposes to oppose them by facts, a prac-
tice which I cannot too highly applaud, being most firmly con-
vinced that no theory can be considered as worth a farthing,
except for the indirect advantage of exercising the intellect,
until experience has shown that it is complete and satisfactory.
Instead, however, of keeping this promise he proceeds to lay
down certain “ propositions, which rest only on the basis of
the evidence of the eyes or experience.” Some of these pro-
positions unfortunately my own limited experience enables me
most flatly to deny. I will beg leave to quote them in order,
with a few remarks.

1. “ When achromatism is obtained by the adjustment of
lenses to particular intervals, as in the case of the Huygenian
eye-piece, such achromatism is absolute and perfect, and not
like that effected by the combination of a concave lens of flint-
glass with a convex of plate or crown glass, which never effects
a complete neutralization of the chromatic aberration, as is
well known.”

The Doctor seems here to confound together two distinct
modifications of chromatic dispersion, which affect such instru-
ments as a telescope or a microscope quite independently, and
must be corrected, if necessary, on quite different principles,
as I have endeavoured to explain, after Professors Robison,
and Airy. The achromatism is in neither case perfect, and
it is impossible to compare them, because they depend, though
in different manners, on the apertures of the lenses employed
as object-glasses and eye-pieces respectively, which are hardly
connected with each other by any laws whatever.

2. “ The only kind of achromatism, produced by convex
lenses, which is known in practice, is when two are adjusted
to an interval equal to one half the sum of their focal distance
or thereabouts.”

Every person who knows anything of the construction of
a telescope is well aware that an erecting eye-piece, consisting
of four lenses, is, when properly made, just as achromatic as
the Huygenian.

3. “ Many modifications of this combination may be made,
as by doubling or tripling the eye- and field-glasses.”

This is very true, and I have applied it with complete suc-
cess, in order to correct a defect totally unconnected with
chromatic dispersion.

N.S. Vol. 10. No. 56. Aug. 1831. Q 4. “In

114 Mr. Coddington’s Reply to Dr. Goring.

4. *In order to form a truly achromatic erecting eye-piece,
there must be a compensation both in that part which erects
or forms the image, and in that which views it; therefore no
achromatic erecting eye-piece can be made with so few as three
lenses.”

This is altogether incorrect both in theory and in practice.
In an erecting eye-piece the compensation of dispersion may
take place any how, provided only that it be completely ef-
fected on the whole. Erecting eye-pieces of three lenses are
not used, though they may be made perfectly achromatic, be-
cause they are liable to another defect which cannot be com-
pensated.

5. An erecting eye-piece can only be made really achro-
matic, (if we do not employ concaves of flint glass,) by com-
bining two Huygenian eye-pieces.”

Did this gentleman ever examine the day eye-piece of a
common hand telescope ?

6. “Such an eye-piece could only be used for viewing an
image, and could never be employed as an engyscope, because
it would have no external focus in front of the bottom glass.”

This is like No. 4, inaccurate, both as to the fact and the
reason. Any erecting eye-piece may be used as a microscope,
though it would serve little purpose on account of the very
small magnifying power that can be thus obtained. Nobody
would, however, find fault with it on that account, any more
than he would condemn a good carving-knife, because it would
not shave him clean. ‘The Doctor then observes, that I have
been at the pains of falsifying my own theories, practically at
least, to the best of my abilities, by presenting to opticians
a compound microscope, termed achromatic, which is con-
structed according to them. He says, “I assert point blank,
that his instrument is as complete a failure as anything of the
sort I ever attempted myself. I have examined one of these
instruments of the latest and most improved construction,made
by Mr. Cary, and can, I think, be positive that both the chro-
matic and spherical aberration of the objective part was wholly
untouched, and that the eye-piece, consisting of four glasses,
was achromatic.”

The history of this instrument is briefly this: On a critical
examination of all the four defects to which a compound mi-
croscope of the ordinary kind is liable, I judged, from theory,
aided in some little degree by my own experience and that of
others, that two might be wholly removed in an instrument of
small volume and price, and the other two so much reduced
as to produce a microscope which might prove very useful to

naturalists

Mr. Coddington’s Reply to Dr. Goring. 115

naturalists who could not afford to purchase very expensive
instruments. As to my success I may appeal to the Doctor
himself, who confesses in the next line that NorTHING CAN
SURPASS THE BEAUTY OF THE FIELD OF THIS MICROSCOPE,
though his firm conviction that this instrument ought not to be
good has so far warped his judgement as to make him assert,
that “nothing more can be made to grow in it [the field ] than
in that of any ordinary compound microscope having a well-
figured object-glass of the same power, and angular aperture,
used with an Huygenian eye-piece, also of equal power with
that applied to the instrument in question.”

Several persons have, to my knowledge, compared my in-
strument, which be it remembered costs but six guineas
and a half, with “ ordinary compound microscopes” made by
the first opticians, for which they had paid twenty or thirty
guineas, and have declared it decidedly superior in every re-
spect. Ifthe Doctor means that it is not so perfect as a com-
pound microscope with an achromatic olyect-glass, I agree with
him most cordially. Neither is a twenty-guinea telescope,
though good of its kind, equal to Sir James South’s twenty-
foot equatorial. Let the Doctor produce me a microscope,
or an engyscope if he likes that word better, with an achromatic
object-glass, which shall magnify distinctly 360 times in linear
measure, pack into a compass of about 24 cubical inches, and
cost but six or seven guineas, and I shall be perfectly satisfied
to yield the palm to him.

In the mean time I earnestly conjure him not to diminish
the value of his own praiseworthy exertions, by incautious
attacks on persons who, if they allow themselves to reply to
him, may easily show that while he diverts himself with
throwing stones, he forgets that he dwells in a house of glass.

I remain, Gentlemen, yours, &c.

Trin. Coll. Cambridge, H. CoppincTon.
July 8, 1831.

P.S. I beg leave to add that I have no pecuniary interest
whatsoever in the instrument which has thus unexpectedly
furnished a subject for controversy. I furnished designs to
Mr. Cary, who in a very spirited manner undertook the ne-
cessary experiments at his own cost, and I certainly feel an-
xious that no unfounded charges should prevent him from de-
riving a fair remuneration from the sale of the microscope.

Q 2 XIII. On

f u6é j

XIIL. On the Thermo- Magnetism of Homogeneous Bodies ; with
illustrative Experiments. By Mr. Wm. Srurceon, Lecturer
on Experimental Philosophy at the Hon. East India Company's
Military Academy, Adiscombe.

[Concluded from page 24.]

Sixth Class of Experiments.

88. Experiments with irregular Masses of Antimony.

ei object of these experiments was that of ascertainin

if the same laws of thermo-magnetic action, as regards
the crystalline arrangement of the metal and point of heat, as
those which were developed in the experiments with cylinders
and cones of antimony could be traced in masses of an irre-
gular figure, by making the point of heat in various parts of
those fine smooth extensive faces of crystalline laminze which
are to be met with only in fractures of large masses which
have been very gradually cooled from fusion.

89. The experiments were made by heating, separately,
particular points in those lamellated faces, and then tracing
the direction of the electric currents by expeditiously apply-
ing the antimony to a magnetic needle, and noting minutely
the character of the deflection; and it appears, from the uni-
formity of the results of a considerable number of experi-
ments on various pieces, that the thermo-magnetic phzno-
mena elicited in irregular masses have precisely the same re-
lation to the position of the metallic films and point of heat
as those displayed by cylinders and other regular forms of
antimony.

90. It will not be necessary to enter into a detailed account
of the several experiments which were instituted for this in-
quiry, as a description of those which were made on one of
the irregular pieces, and of the resulting phenomena, will be
sufficient to illustrate the whole. And I have every reason to
believe, that the same laws which govern these phzenomena,
will be found to appertain to all similar crystalline arrange-
ments of antimony; that they will uniformly be developed
under similar circumstances, and consequently that they are
intimately related to the crystallization of the metal.

91. The piece of antimony on which these experiments
were made, weighed about three pounds; it was separated by
the blow of a hammer from a large mass, and the frac-
ture exposed a smooth triangular face of parallel crystalline
plates, without presenting any intersecting edges of metallic
Jamine whatever. This triangular face will be represented
by figs. 16, 17, 18; and the arrows in those figures will show

the

On the Thermo-Magnetism of Homogeneous Bodies. 117

the directions of the electric currents as indicated by the de-
flections of the magnetic needle, when the point of heat was
near to the angles a, 6, c, respectively.

92. When the spirit-lamp was held for a few moments at
the angle a, still keeping the point of the flame on the face
of the fracture, the electric streams were diffused over every
part of that surface from the point of heat towards the op-
posite edge; as shown by the directions of the arrows, fig. 16.
Comparatively strong currents were detected in the edges a 6,
and ac; but in consequence of the general flow of these cur-
rents being nearly at right angles to the edge bc, no magnetic
force could be detected when that side was held over and
parallel to the needle. On leaving the face abe, the electric
tide swept the general surface of the metal, flowing in various
directions, and returning by numerous windings to the point of
heat. By this distribution, and consequent attenuated state
of the electric force, the thermo-magnetic energies were com-
paratively very feeble on every part of the metal excepting the
face abc; on which alone they were displayed with prompti-
tude and regularity.

93. When the point of heat was at 4, the whole of the tri-
angular face became again magnetic, displaying phznomena
of precisely the same character as those which had been eli-
cited when the point a was excited; and the distribution of
the electric forces had again a decided reference to the point
of heat; emanating therefrom, and flowing with as great an
uniformity over the surface of the fracture as if it had been
a conductor from the copper to the zinc of a single galvanic
pair. ‘The arrows in fig. 17. will indicate the distribution of
the electric force over the surface of the lamellated fracture
when the point of heat was at b.

94. When the fracture was heated at c, the thermo-mag-
netic phenomena were again displayed with very nice pre-
cision and uniformity on that particular face of the metal;
whilst on the other parts of the surface they were confused
and irregular; showing that the electric forces on those parts
were dispersed in various directions, and enfeebled by their
separation, or by their returning to the point of heat, through
the body or general mass of the metal. Fig. 18. will show the
direction of the electric tide on the face abc, when the point
c was excited by the flame of a spirit-lamp.

Remarks.

95. ‘The uniformity displayed in the results of the preced-
ing class of experiments confers on them a very interesting
character in these investigations. In connexion with those on

regular

118 Mr. W. Sturgeon on the Thermo-Magnetism of

regular masses, these experiments establish a very important
point, by exhibiting in the most striking and satisfactory man-
ner an intimate connexion between the crystalline arrange-
ment of the metal, and the distribution of the electric powers
by heat; for, to whatever point in the flat lamellated face of
this system or group of parallel scales heat was applied, the
electric forces were directed over the planes of the laminz
from the heated point; and having traversed the general sur-
face of the metal, returned to that point again, across the edges
of the films, in precisely the same manner as in the experi-
ments with solid cones and cylinders,—a circumstance highly
demonstrative that the thermo-magnetic forces in both sets of
experiments have the same specific origin, and are actuated
by the same cause. The fountain of all the phenomena ap-
pears to be in the crystalline arrangement of the metal, and
the direction of the electric and magnetic forces to be refer-
able to the point of heat.

96. It very often happens that fractures such as have been
described (88) (91), are bordered on some of their sides with
piles or groups of laminz, unfavourably situated for experi-
ments of this kind; presenting their thin edges, instead of
their planes, in the face of the fracture. When, however, the
method of experimenting becomes known, these trifling in-
conveniences are not of much consequence to the uniformity
of the thermo-magnetism displayed by the smooth part of the
fracture under examination.

97. In the first place, the flat scaly surface on which the
experiments are to be made, ought to be as extensive as pos-
sible; at least two inches across; if larger, the better. Should
any side of this face present groups of the thin edges of la-
minz, they may be easily removed, either by the saw or by the
hammer: if those groups be not very extensive, their re-
moval will not be necessary.

98. The principal circumstance next to be observed is, that
the flame of the spirit-lamp does not touch those unfavourable
crystals. The selected point of heat must always be on some
part of the flat lamellated face under examination, and near to
some angle. A momentary heat must suffice, and the plane
immediately and dexterously applied to the magnetic needle;
the deflections of which will unerringly indicate the electric
current to be flowing over that surface from the heated point
to the opposite side.

99. I have succeeded in discovering a method of forming
square bars or prisms of antimony, which observe a rigid
uniformity in the display of thermo-magnetic phaznomena, by
heating them either partially, or equably, at one end only.

And

Homogeneous Bodies ; with illustrative Experiments. 119

And I now find that I can predict with certainty the mag-
netic character of any side of the bar, by paying attention to
certain circumstances connected with its casting. I have cast
several sets of square bars, of an uniform size and figure, under
precisely the same circumstances, and have never yet found
one single bar to deviate from the general law. One of those
sets consisted of fifteen bars, all of which observed the same
laws of thermo-magnetic action. I have, however, in vain tried
to obtain them of an uniform power, the thermo-magnetism
of some of them being much more energetic than that of others.
This circumstance, which I hope soon to obviate, and some
others which I find associated with the display of their thermo-
magnetic phenomena, but which I have not yet had time to
investigate, prevents my giving a description, in this place, of
the circumstances under which I have hitherto cast these prisms
of antimony; the thermo-magnetic character of which can
easily be predicted before the metal enters the mould*.

100. In general, these bars possess a considerable degree
of power as thermo-magnets ; and when four, or more of them
are properly combined, their conspiring energies on the mag-
netic needle may be very satisfactorily exhibited to every
auditor in the most spacious lecture-room.

101. I have also been enabled to cast discs of antimony,
which do not vary from each other in the character of their
thermo-magnetic qualities. I have not however, as yet, had time
to investigate the whole of the circumstances which I suspect
to be connected with the communication of that power to the
metal, and therefore beg permission to reserve the detail of
the experiments till another opportunity. I mention them
in this place merely as facts, which I can at any time repeat.
I will further observe, however, that I am of opinion that the
thermo-magnetism displayed in the prisms and discs already
noticed, may be traced to the same source as that displayed
in other forms of antimony; that is, to the crystalline arrange-
ment of the metal; and that electricity is intimately associated
with the process of crystallization generally. ‘This opinion
is highly favoured by the well-known fact of electro-polarity
being exhibited in the tourmaline and some of the crystallized
gems: and as regards the metals, I imagine that the experi-
ments and observations I have hitherto detailed, are amply

* It is next to impossible to cast bars of antimony of considerable di-
mensions which will not exhibit magnetic phenomena by heat; indeed,
bars of almost any size, or masses of any figure whatever, whether regular
or irregular, display those powers more or less. It however requires con-
siderable attention to obtain several pieces of antimony which will observe
an uniformity of thermo-magnetic action.

demonstrative

120 Mr. W. Sturgeon on the Thermo-Magnetism of

demonstrative of the connexion in that class of homogeneous
bodies. And I am inclined to believe, that future labours in
this curious philosophical field of research, will ultimately
establish crystallography amongst those interesting sciences,
which are subordinate branches, and obedient to the laws, of
electricity.

103. There are, however, thermo-magnetic phenomena dis-
played by homogeneous metals, when experimented with in
certain forms, which do not appear to be very reconcilable to
the hypothesis of electro-crystallography. ‘They seem to de-
pend upon some other cause than any which that hypothesis
embraces: and as they are exhibited under different circum-
stances to any which have yet been noticed, the experiments
by which they are elicited will require to be described as a
distinct class.

Seventh Class of Experiments.

104. Notwithstanding the opinions which have been set
forth to show that thermo-magnetic energies are not exalted
in combinations of metals, by employing them of large dimen-
sions, and that a pair of particles, however small, or wires
exceedingly thin, will develop the same extent of power as two
bars of considerable dimensions; I was led to imagine that
the same law might probably not extend to the innate mag-
netism displayed in homogeneous metals by heat. My in-
quiries were therefore directed to large masses of those metals,
in which, whilst experimented on in small pieces, I was unable
to discover the least trace of this extraordinary power; and
the results were such as to answer my anticipations in the most
ample and satisfactory manner.

105. Experiments with large Masses of Zinc.—The first
piece of zinc in which I detected thermo-magnetic action was
a rectangular cake, or flag, which had neither been rolled nor
hammered. It was about 14 inches long, 8 inches broad, and
‘75 inch thick, and weighed about 17 pounds. This mass
of zinc, when heated at one corner only, displayed magnetic
powers in a very exalted degree, and would deflect a compass
needle, on which the magnetism of the earth was not neutral-
ized, 20°, by the first impulse, when one of its edges was
held in the magnetic meridian and close to the glass cover of
the instrument; but in consequence of a fracture in one of its
edges, the thermo-magnetic phenomena were not so nicely
regulated in this piece as I have found them to be in other
masses of zinc, which are uniformly sound on every side.
I will therefore describe experiments which were made on a
whole sound flag of zinc, weighing 42 pounds, 2 feet long, 8°5
inches broad, and about 1 inch thick.

106. The

Homogeneous Bodies ; with illustrative Experiments. 121

106. The thermo-magnetic phenomena were promptly and
uniformly displayed by this mass of zinc, and were precisely of
the same character as those which I have observed in experi-
ments with all similar masses that I have yet examined. The
have an evident reference to the point of heat; and I believe
they may be taken asa general standard for those which would
be developed by all similar masses when operated on by the
same process.

107. The experiments were made by heating one corner of
this mass of zinc in a common fire, and keeping the other
parts of the metal as cool as possible. When thus heated, the
mass was held in various directions over the magnetic needle,
the deflections of which were taken as an indication for the
direction of the electric currents. In this manner the thermo-
magnetic powers of the zinc were ascertained, whilst it was
partially heated at its several angles in succession.

108. If a, 6,¢,d, fig. 19. be permitted to represent one of
the flat faces of the zinc-plate, then the arrows in that figure
will give a tolerable representation of the directions of the
electric forces, as indicated by the deflections of the compass-
needle when the point of heat was at the angle d. By con-
templating this figure, it will be observed that the electric
forces are projected, as it were, from the heated angle into the
body or field of the mass, over which they become generally
diffused; but separating and expanding in different directions,
they sweep the surface of the metal in recurving tides towards its
edges, by which routes they again return to the heated point.

109. The straight arrows in fig. 19. would seem to indicate
that the electric forces in those parts of the metal were di-
rected in right lines, which is not strictly correct. ‘Those
arrows are drawn to show the lines of greatest energy, or those
parts of the metallic surface which, when presented to the
needle, produce the greatest deflections, and are the deter-
mined resultants of the numerous curvilinear forces which are
in active play during the transient disturbance of temperature
in the metal.

110. It will appear evident by inspecting the figure, that
on the surface of the rectangular mass, there would necessarily
be two neutral lines, one on each side of the diagonal arrow,
which would be determined at right angles to the aggregate re-
curving electric forces, and may be represented by the dotted
lines dn,d n. These lines, are those in which amagnetic needle,
unsolicited by any other force, would arrange itself, and were
discovered by its uniform repose whilst situated close to those
parts of the metal. The situations of the neutral lines, how-
ever, are not constantly the same; for as they are determined

N.S. Vol. 10. No. 56. Aug. 1831. K by

122 Mr. W. Sturgeon on the Thermo-Magnetism of

by the direction of the electric forces, and those forces again
by the distribution of heat, the situations of the dotted lines
dn, dn, will also vary with the circumstances of heat.

111. When one of the ends ad, fig. 20. of the rectangular
mass is uniformly heated, the distribution of the electric
forces will be indicated by the arrows in that figure. Here
again, it will be observed, that the electric forces are projected
Jrom the heated end into the area of the plate, and by re-
curving sweeps, return to that end again along the parallel
margins of the metal. In this case, the neutral lines, and lines
of greatest energy, are parallel to each other, and also parallel
to the sides ab, dc of the rectangular plane.

112. As a similar distribution of the electric forces to that
represented by fig. 19. is uniformly elicited by heating any
of the angles separately, the same system of arrows will serve
to illustrate that distribution, to whatever angle heat may be
applied. If, for instance, the angle a were to be heated, the
points of the straight arrows dc, da, would then be directed
to a, or towards the point of heat; whilst the feathered end
of the former would be directed towards 6, and that of the
latter towards the angle d. The central or diagonal arrow
would be directed from the angle a to the angle ¢; and in
the same way the system of arrows may be considered to be
situated with respect to any other heated angle. ‘The system
of arrows in fig. 20. will also apply to either of the ends of
the metal when uniformly heated between the angles.

113. As both faces of the zinc exhibited thermo-mag-
netism of the same character in all the preceding experiments,
whatever has been stated concerning those experiments will
equally apply to both sides, or flat faces of the metal, and
I imagine to all similar masses of zinc. I must here observe,
that the electric forces very seldom reach to the cold end of
the mass, but approximate thereto in proportion to the ad-
vances of heat. They are the most powerful near to the
heated point, and become more and more languid as they
recede from it, till at length their energies are entirely lost
in the more remote parts of the metal.

114. Experiments with Masses of Copper.—Copper is one
of those metals, the thermo-magnetic energies of which are
not very easily detected in separate homogeneous masses, un-
less they be of large dimensions. The most satisfactory re-
sults I have ever obtained from experiments on this metal
were elicited by a rectangular mass, about two inches thick,
and weighing about 95 pounds. ‘This huge piece of copper,
which by the interest of Mr. Marsh I was permitted to ex-
amine, belongs to the Royal Arsenal. The experiments Hes

made

Homogeneous Bodies ; with illustrative Experiments. 128

made in precisely the same manner as those described with
masses of zinc; and the results, excepting in degree, were ex-
actly the same in both metals. The thermo-magnetic energies
were very promptly and uniformly displayed in this mass of
copper, but were exceedingly feeble when compared to those
developed by a mass of zinc less than half its size. With
the latter metal, a needle, on which the terrestrial magnetic
powers were in full play, could be made to sweep an arch of
100°; whilst with the unwieldy mass of copper, it required
the soliciting terrestrial force to be entirely cut off from the
needle in order to obtain a sweep of 6° or 8°.

115. There does not seem to be that uniformity in the dis-
play of thermo-magnetism by thin metallic plates as is ob-
served to be developed by those of considerable thickness.
The phznomena, when thin plates are employed, although
the metal be neither rolled nor hammered, assume a very ca-
pricious character, and appear to be governed by laws which
are not easily traced to any general standard.

116. I am not at present prepared to say to what cause
these phenomena are attributable: they seem to be of a
distinct order, and not referable to the laws of crystallization.
They may possibly be traced to a difference in the progress
of heat in the several parts of the metal, moving with dif-
ferent degrees of celerity in the margin and body or area of
the mass. Should this conjecture be correct (and I have some
reasons to think that it is true), I imagine that this class of
experiments will exhibit a very prominent feature amongst all
those, which, from time to time have been advanced for the
solution of the highly important problem of terrestrial mag-
netism, more particularly in that branch of the inquiry which
relates to the diurnal variation.

117. Experiments with Spheres of Zinc.—To carry the ana-
logy of experiment still closer to terrestrial magnetic action, I
have had cast, globes of zinc of different sizes, with a view of de-
tecting some law by which their thermo-magnetic energies are
exhibited when heat is partially distributed over the surface of
the sphere, in imitation of the sun’s action on the face of the
earth. One of these globes is solid, and about 5°54 inches
diameter, weighing nearly 23 pounds; another, which is
hollow, and 10 inches diameter, weighs 64 pounds, the thick-
ness of the metal being about °75 inch.

118. With these spheres I have as yet gained but little
information, owing, as I suppose, to the difficulty which I have
experienced in keeping the various parts of their surfaces at
temperatures sufficiently remote from each other, I have,
however, succeded in deflecting a needle by applying to it the

R 2 10-inch

124 Rev. P. Keith on the Conditions of Life.

10-inch globe, partially heated, to a much greater angle than
any that has ever been ascribed to diurnal variation. This re-
sult, insignificant as it may appear, and far from answering my
expectations as to the extent of magnetic power developed by
the sphere, sufficiently warrants the prosecution of the inquiry.
The experiment has demonstrated the existence of the mag-
netic power in a homogeneous sphere of zinc, and the deve-
lopment of that power by heat. ‘The field of inquiry is thus
successfully penetrated, and future investigations may possibly
lead to the most interesting results.

119. A sphere of 10 inches diameter, which is the largest
I can at present command, is much too small for experiments
of this character. With a globe 30 or 40 inches in diameter,
experiments might be made on a magnificent scale, and I ap-
prehend with the most satisfactory results. A metallic sphere
of such dimensions, with the necessary machinery for experi-
ment, would require a sum, which perhaps but few indivi-
duals would be found willing to lay out on an inquiry which of
is more of a national than of an individual interest. Researches
of this nature would be the most likely to be successful were
they pursued under the patronage of governments, or of
wealthy scientific associations. ‘The experiments might then
be carried on under advantages the most favourable to insure
regularity and uniformity in the results, provided they were
conducted under the superintendance of persons who have
proved themselves competent to the task. They might also
be pursued to an extent which no individual could hope to ar-
rive at, and with a success that probably might at once set
this sublime philosophical problem completely at rest.

Artillery Place, Woolwich.

N.B. I have succeeded in magnetizing an iron sphere by
means of a thermo-electric combination. The same sphere
becomes very highly magnetic when under the influence of
the electricity excited by a small galvanic pair immersed in salt
water; giving direction and inclination to a magnetic needle,
highly imitative of those phenomena as exhibited by the ac-
tion of the earth. A description of the apparatus and mode
of experimenting will be given in my next communication.

XIV. Of the Conditions of Life. By the Rev. Patrick Kriru,
[Conc'uded from page 40.]

Aliment.— ALL substances capable of affording nourishment

to living beings are aliments; and no living

being can subsist any great length of time without the use of

them.

Rev. P. Keith on the Conditions of Life. 125

them. Ifa plant is deprived of the access of the moisture of
the soil, it languishes, and withers, and dies. If an animal is
deprived for a length of time of all nourishment, a feeling of
pain is excited in the region of the stomach, followed by faint-
ness and loss of strength, which, without new supplies of food,
would ultimately and inevitably terminate in death. As plants
cannot range the fieldsin quest of nourishment, it was necessary
that some provision should be made to furnish them with due
aliment, without any effort of their own; accordingly the Creator
has provided that they shall find their food in the moisture of
the soil in which they grow. ‘Their food is thus already
digested, and they take it up in a fluid state by the slow and
protracted process of absorption. Animals, on the contrary,
having functions to perform incompatible with a stationary
mode of existence, and with the assumption of food by the
slow process of absorption, are furnished with the means of
taking in, at certain intervals pointed out by the sensation
of hunger, a competent supply of aliment in a solid state,
which they have the means of digesting, and of preparing for
final assimilation.—The food of plants consists chiefly in the
moisture which they find in the soil, containing in solution a va-
riety of alimentary ingredients. But we have reason to believe
that they derive part of their food from the atmosphere also.
The leaves attract and absorb the moisture. They inhale also
its gases; and there are plants that live and thrive without any
other food. The Epidendron Flos-aéris may be quoted as an
example.—The food which animals affect is of various de-
scriptions according to the species. Some animals are grani-
vorous, as many birds. Some are graminivorous, as the sheep
and the ox; others are carnivorous, as the lion and the tiger.
Man eats almost anything, and drinks almost anything, but
he likes to have his victuals cooked.

It has been thought that a line might be drawn dividing the
animal from the vegetable kingdom upon the ground of the
character of the food affected by each. Such, particularly, is
the opinion of M. Mirbel*. Plants feed, it is said, upon un-
organized substances—earths, salts, water, gases; animals upon
substances already organized; that is, either upon other animals,
or upon vegetables.— We do not regard it as a very good, ora
very correct rule. Animals thrive well upon milk alone, which
is not an organized substance. If you say that it is the product
of an organized being, let it be remembered that it is also
a very good food for vegetables. In short, the chief food of
plants as well as of animals is either animal or vegetable sub-
stances in a state of solution; and though animals may feed

* Traite d' Anat, et de Phys, veg.
upon

126 Rev. P. Keith on the Conditions of Life.

upon substances that are still in an organized state, yet they
cannot convert them into nourishment till they have destreyed
their organization in the stomach. Is it certain that all animals
require a food that has once been organized?) What is the
food of Cancer salinus ?

A better criterion for distinguishing the animal from the
plant will be found in the attribute of sensation. For though
there may be some phenomena that give countenance to the
idea of vegetable sensibility, yet they are not such as the phy-
siologist can confidently rely upon; and as the attribute of
sensation distinguishes the animal from the plant, so their as-
sumption and assimilation of aliment, and their origin and
mode of growth, will distinguish them both from the mineral.
If this last criterion had been kept in view, the noted definition
of Linnezus would have been less incorrect: “‘ Lapides crescunt ;
vegetabilia crescunt et vivunt ; animalia crescunt, vivunt, et sen-
tiunt*,”—Stones grow; plants grow, and live; animals grow,
live, and feel. But the truth is that stones do not grow in the
sense in which plants and animals grow; not by the intro-
susception and distribution of aliment throughout their whole
substance, but merely by the apposition of new particles added
to the external surface. In this respect the definition is faulty.
In other respects it is perhaps well enough; and in brevity
and decision of tone it will not be easily surpassed.

Upon the principle which we adopted in our definition of
life, namely, that of a copious enumeration of particulars, I
submit the definitions that follow, with a view to mark out the
boundaries of the three kingdoms of nature :—A mineral is a
mass of lifeless matter, inorganic, inert, insentient; not aug-
mentable by nutrition, but attaining its bulk merely by the
external and mechanical or chemical apposition of new parts
or particles.—A vegetable isa living and organized body, inert,
insentient; springing from and producing a germ that is aug-
mentable by nutrition; and fixed, by a root, to the soil, from
which it absorbs its principal nourishment already in a fluid
state.—An animal is a living and organized being, self-moving,
sentient; springing from and producing a germ that is aug-
mentable by nutrition, and ranging in quest of aliment, which
it takes up chiefly in a solid state, and subjects to the action
of digestive organs.

There are assignable limits, then, which separate the three
kingdoms of nature; between the mineral and vegetable, orga~
nization ; between the vegetable and animal, sensation. In
an unorganized body there is no community of interests among
the different parts, and no part that is necessary to the well-

* Philosophia Botanica, 2.
being

Rey. P. Keith on the Conditions of Life. 127

being of any other part. Cut or chop off any portion you
please from a block of marble, and the remaining portion shall
know nothing of it. In an organized body, every organ is use-
ful to every other organ, and no organ is made for the sake of
itself alone. Each sympathizes with all the rest, and each has
a common interest in the welfare of the whole. The aliment
which a plant or animal takes up it distributes to every member.
Manure and water the root of a plant, and the leaf and flower
will soon give indications that they participate in the benefit
conferred; lop it severely, and the branches will suffer.—Give
toan animal its due supply of food, and every organ is refreshed.
Cut or chop off from it a limb, or part of a limb, and you ex-
cite a sympathy throughout the whole fabric, with a feeling of
pain and of injury expressed by cries, or manifested by con-
tortions of body. .

Yet the limits separating the several kingdoms are not, in
all cases, conspicuously displayed.—Look at the lower orders
of vegetables—the algze, the fungi; and in some of them it is
with difficulty that you can discern even the faintest traces of
organization. A mere crust adhering to the surface of a rock,
as In the case of many of the lichens; or a mere mass of jelly
_ covered with a fine epidermis, as in the case of many of the
tremellz, is all that you have for a plant. It is but little ele-
vated above the level of the mineral.— Look at the lower orders
of animals, and you find the same want of characteristic marks
among them. ‘The organization of a polype seems to be but
iittle beyond that of a tremella: but its power of loco-motion,
which is evident, and its capability of sensation, which is pre-
sumptive, are tokens that indicate its superiority to the plant.

As you advance to the higher orders of vegetables, the orga-
nization begins tobe more complex, and the plant more perfect;
and thus you rise through the several orders till you reach the
highest and most perfect of all, producing root, stem, branch,
leaf, flower, and fruit, in the perfection of their kind, and giving
indications of organic and living function, and of the process
of internal nutrition, in the absorption, elaboration, transmis-
sion, and distribution of alimentary fluids in peculiar and ap-
propriate vessels. As you advance to the higher orders of
animals, the organization begins to be more complicated also,
and the animal more perfect, establishing the physiological
maxim—that of all organized beings, whether plants or animals,
the perfection of the individual is in the direct proportion of
the complexity of its organization. Hence the organization
of the animal is soon found to surpass in complexity that
of the vegetable. Both havea variety of organs in common—
tissues—the cellular, the lamellar, the vascular, the fibrous.

Both

128 Rev. P. Keith on the Conditions of Life.

Both have an alimentary and a sexual apparatus; for both
grow and propagate their kind. Both have an apparatus for
the propulsion and distribution of fluids, which they have the
capacity of assimilating to their own substance.—But animals
have additional faculties, and the additional faculties in ques-
tion have their source in additional organs; while the organs
conferred correspond to the wants of the individual. The food
of the plant is already digested ; but the animal has its food to
digest. Hence the necessity of a stomach. ‘The plant is sta-
tionary; but the animal moves. Hence the necessity of a
muscular apparatus. The plant is insentient; but the animal
is endowed with the faculty of sensation. Hence the cerebral
system, the source of thought, perception, consciousness, me-
mory, volition, loco-motion. In the lower orders of animals
these additional properties are not very distinctly marked ; but
as you ascend the scale, they become more and more visible
till at last you reach man, in whom they exist in the highest
degree.

Aeration.—No living being can thrive, or even continue to
exist, without the access and contact of atmospheric air.
The seeds of vegetables will not germinate if placed in vacuo.
Ray introduced some grains of lettuce-seed into the receiver
of an air-pump, which he then exhausted: they did not ger
minate, but they germinated upon the re-admission of the air;
which shows that access of air is a condition necessary to the
germination of seeds*. The experiments of Homberg seem
indeed to militate somewhat against this conclusion. They
are recorded in the Memoirs of the French Academy for the
year 1669; and the inference deduced from them is, that seeds
in general do not germinate if deprived of atmospheric air;
but that cress-seed, lettuce-seed and a few others will germi-
nate even in the vacuum of an air-pump. But the same ex-
periments when repeated afterwards by Boyle, Muschenbroek,
and Boerhaave, with a much better apparatus, did not confirm
the latter part of the result. On the contrary they all tended
to prove that no seed germinates in the vacuum of an air-
pump, and that in the cases of germination mentioned by
Homberg, the vacuum must have been very imperfect. ‘The
same experiments were again repeated by Saussure the younger,
who says that the seeds of peas gave indications of germination
in vacuo in the course of four days, but never effected any de-
velopment of parts beyond the mere protrusion of the radicle+.
— We conclude, then, upon the whole, that in a perfect vacuum
no seed will germinate; but that in the most perfect vacuum
hitherto formed by human art, some seeds may germinate.

* Phil. Trans. No. xiii. + Saussure sur la Vég. chap i, sect. 1.

The

>

Rev. P. Keith on the Conditions of Life. 129

The same condition is necessary to the vegetating plant.
Grew having discovered, in a leaf that he was examining, a
number of little bags or bladders, filled as he thought with
air, drew the conclusion, and maintained the doctrine, that
leaves are the lungs of plants. M. Papin, with a view to as-
certain the point in question, introduced into the receiver of
an air-pump an entire plant, root, stem, and leaf: the con-
sequence was, that it very soon died. He then introduced a
plant by the root and stem only, with the leaves and branches
exposed to the influence of the atmosphere: still the plant
died after a while; but it lived much longer than in the former
case, and warranted him in concluding, as he thought, that leaves
are indeed the lungs of plants*. Whether this conclusion
was legitimately drawn trom the premises, or noi, we will not
at present stop to inquire. Enough was done to show that
plants cannot continue to live without the access and contact
of atmospheric air. They will not even grow with vigour
unless they have an abundant supply; as he who has the ma-
nagement of a hot-house too often discovers to his cost. The
plant that grows where there is no free circulation of air springs
up slender and sickly. The plant that is exposed to the action
of the stormy blast springs up stout and robust.

Of the truth of the same conclusion as applicable to animals,
it will scarcely be necessary to offer any formal proof. It comes
so completely home to every one’s own experience, that he
must be a bold man who would deny it; yet if proof were
wanted, it would be found in the death of many a poor mouse
that has been placed in the receiver of an air-pump for the
purpose of experiment.

There are, it is true, some apparent exceptions to the above
rule. It has been said of the Truffle, that it vegetates without
the access of air, because it vegetates wholly under ground.
But it is very well known that air penetrates the soil toa depth
beyond that at which the Truffle is found. It does not there-
fore vegetate without aération. For the same reason it has
been thought that the roots or bulbs of plants whose stem dies
down to the ground in the winter must needs vegetate without
air. But air is conveyed to them in the moisture of the soil;
and of some of them it may be said that they hybernate rather
than vegetate in the winter: at any rate they are not deprived
of the access of air+. But itis in the animal kingdom that the

excep-

* Phys. des Arb. liv. ii. chap. 3.

+ [We may add, in confirmation of this reasoning, that it has been shown
by Mr. Bowman, (Trans, of Linn, Soc. vol. xvi. p. 413, &c.) that the squa-
me of the subterranean stem of Lathraa squamaria are real leaves and
organs of aération, But the same botanist remarks, that Cuseuta, Listera

N.S. Vol. 10. No. 56, Aug. 1831, S Nidus

130 Rev. P. Keith on the Conditions of Life.

exceptions are the most striking;—not in the department of
Fishes, though their element is even the water; but in that of
the Amphibia. Live toads, snakes, and lizards have been
found imbedded in solid masses of stone, or of coal, at a great
depth below the surface, and without any possibility of the
access of air*. They are facts occurring about as often, and
are about as well authenticated, as the sight of a mermaid.
We cannot well refuse our assent either to the one or the
other; and yet we cannot give it without a sort of sceptical
reluctance. Yet if the fact in question is anything different
from that of a long protracted hybernation, we are altogether
without the means of accounting for it.

Temperature.—The phzenomena of life have never yet been
exhibited except within a certain and limited range of tempe-
rature. ‘Too great a degree of heat, or too great a degree of
cold, is equally injurious to it. Ata very low temperature,
as towards the poles, plants and animals are often frozen to
death. Ata very high temperature, as at the equator, they
are apt to perish through excess of heat. But they have the
capacity of preserving their due temperature under the influ-
ence of many opposing causes. In the midst of the frosts and
snows of winter, plants maintain a temperature which is always
above that of the surrounding atmosphere; and even under
the burning heat of a vertical sun their temperature is never
raised very high. But different plants affect different tempe-
ratures, and you cannot well naturalize them in climates to
which they are not indigenous. You may indeed have all
varieties of them in the same latitude; but it shall be in the
conservatory, or in the hot-house, and if not, it shall be at
different altitudes. ‘Tournefort noticed this fact, in the case
of the plants growing on Mount Ararat; and Humboldt gives
us a similar account of the vegetation of the mountainous dis-
tricts of South America. In ascending the Andes within the
tropics, oranges, pine-apples, and all manner of delicious fruits
and vegetables, are found on the lower grounds. Maize,
plantains, indigo, cacao, at an altitude of from 3000 to 5000
feet. Cotton, coffee, sugar, at the same altitude, but ascending
still higher. Wheat, and other European grains, together
with the oak and other forest trees, at the altitude of from
6000 to 9000 feet. The pine still lingers at an altitude of
13,000 feet above the level of the sea. From 13,000 to 15,000
feet, you have grass and lichen, which last creeps up still

Nidus Avis, Monotropa, and Orobanche, are destitute of true leaves, and
are consequently incapable of drawing sustenance from the atmosphere.
These latter plants, therefore, appear to present real exceptions to the rule
here vindicated by Mr, Keith.—Epir. |
* Phil. Mag. March 1817. .
higher,

Rev. P. Keith on the Conditions of Life. 131

higher, adhering to the surface of the porphyritic rock, and
insinuating itself even under the perpetual snow *.

Similar observations are the result of our inquiries into the
animal kingdom. The bear is a native of the polar regions.
The elephant, lion, and tiger are indigenous only to countries
near the equator. A forcible and sudden change of climate
would be fatal, we may believe, to either. For although bears,
lions, and elephants are found to live in countries of which
they are not natives, it is only under the protection and fos-
tering care of man. Man lives in almost all climates, but not
with equal comfort. He can accommodate himself to cold
climates by means of clothing; and to warm ones by going
without it. The Greenlander inhabits regions bordering on
80° of north latitude, where the mercury freezes in the ther-
mometer, that is, at 40° below zero; and yet the temperature
of the blood never falls much below 96° of Fahrenheit. ‘The
negro lives under the hot and burning suns of the torrid zone,
and yet the temperature of the blood never rises much above
96°. Further, plants and animals seem to be endowed with
extraordinary capabilities in extraordinary circumstances.
On the banks of a thermal river in the island of Lugon, the
largest of the Philippines, Sonnerat found the Aspalathus, or
African Broom, and the Vitex Agnus-castus growing, and, as
we may suppose, thriving, though their roots were swept by
the water at a temperature of 174°. In Italy Conferve are
are said to be found occasionally in the thermal springs,
though heated even to the boiling point. In the above island
of Lugon, Sonnerat saw fishes frolicking in a hot spring of the
temperature of 158°. Inthe province of Quito in South Ame-
rica, Humboldt saw fishes thrown up from the bottom of a
volcano, together with water and heated vapour, that raised
the thermometer to 210°. This was quite high enough to
have killed and boiled European fishes; but the fishes in
question were still alive.

Wonderful as the above relation is, it is surpassed by the
following facts. In 1760 when Du Hamel and Tillet were
conducting some experiments that required the heat of an
oven, a girl was found who offered to go into it, to note the
height of the thermometer, and who performed her task with
the most perfect nonchalance ; the mercury standing, ultimately,
at 288°. The curiosity of philosophers being roused by the
announcement of this fact, Sir Charles Blagden, Sir Joseph
Banks, and some other men of science exposed themselves to
a heat, first of 220°, and afterwards of 260°, without suffering
any particular inconyenience. ‘The pulse was quickened to
140 beats in a minute; water was boiled and beef-steaks were

* London Encyclopedia, Andes. + Library of Useful Knowledge.

S 2 dressed ;

132 Rev. P. Keith on the Conditions of Life.

dressed; and yet the temperature of the body never rose be-
yond 101° of Fahrenheit*. Thus there is in plants and in
animals something that resists and controls the influence of
chemical agents, and that something is the attribute of life.
The dead animal substance, the beaf-steak, was broiled, but
the living animal substance remained unaffected.

Connected with temperature we have the very singular phze-
nomenon of the hybernation of plants and animals, that is,
of some peculiar species of them; for all plants and animals
do not hybernate. The state of hybernation is a state of tor-
pidity, induced by a low temperature, and lasting till the colds
of winter have gone. ‘The living functions are suspended.
In plants there is no absorption, no nutrition, no flux of juices.
In animals, there is no respiratien, no assumption of aliment,
nor circulation of fluids; or, if this last process is at all carried
on, itis inthe most languid manner. Yet life is not extin-
guished ; it is not even injured,’ but rather it is preserved
from accidents that might be fatal to it; and when the return
of spring restores again the due temperature, the individual
resumes its living functions, and its hybernation ceases.

Among plants, the bulbous-rooted are said to hybernate,
and the bulb is regarded as being the winter-quarters of the
future plant. ‘They do not however hybernate in the strictest
sense of the term; for if you leave them in the soil for the
winter, and inspect them now and then, you will find traces
of the growth and development of the infant plant, even in
the season of hybernation.— But the hybernation of animals is
the most complete. In them the living functions are really
and truly suspended, and no traces exhibited of the growth
of parts. The snake, the dormouse, the swallow+, the bat,
are examples of hybernating animals. They roll themselves
up into the smallest compass possible, and, as it may best suit
the species, take up their winter-quarters in the earth, or in
clefts of rocks, or in holes of walls looking to the south. If
you detect them in their hiding-place, you may handle them
or pinch them or roll them about; and they shall know
nothing of it till they are exposed to the influence of a gradual
warmth. ‘Their torpor is said to be the most profound at the
temperature of from 5° to 7° above zero. If they are sud-

* Phil. Trans. (abridged by Hutton), vol. xiii. p. 695.

+ Much has been written about the annual disappearance of swallows ;
some maintaining that they hybernate; others that they merely emigrate.
It is certain that such stragglers as have not joined in the general flight
do actually hybernate. This [ can affirm with confidence, from the fact of
my having once found, in the midst of winter, a solitary swallow, in a
torpid state hybernating under the thatch that covered the ridge rafter of
the roof of a carpenter's shop. It revived upon being exposed to the
warmth of a fire; but the weather being still too cold, it soon died.

denly

=

——

Rey. P. Keith on the Conditions of Life. 133

denly exposed to a temperature that is either much lower or
much higher, they are roused indeed into life, but the expo-
sure kills them. The natural and gradual increase of return-
ing solar heat is that which suits them the best.—Thus the
attribute of life preserves them even in hybernation, and is
ready to give them fresh activity when the due temperature
returns.
Death.—By an irreversible decree of the original Giver of
life, every living being must submit to the stroke of death,
which is, as we have already observed, an extinction of all
living function, and of all possibility of living function. ‘There
is no exemption, there is no escape. ‘There is no way of
eluding the grasp of this ghastly King of Terrors;— mors nescia
flecti ;—mors ultima linea rerum. It seems a hard condition,
because it deprives us of all we hold dear. What a boon,
what a blessing is life! And what would a man take in exchange
for it?—Even vegetables seem to be conscious of its value,
though we regard them as being destitute of the faculty of
sensation. In the “fine frenzy” of the poet, the trees of the
forest are made to rejoice, and corn-covered valleys to laugh
and to sing*. Much more is the blessing of life cognoscible
by animals who are endowed with organs of sense and of
feeling.—See how the tender lamb frolics in the enjoyment
of its newly acquired existence !—See how the birds wanton
in air !—See, above all, how man appreciates the value of the
gift;—and see his “longing after immortality,”’—when parti-
cipating, freely, in the gratifications which life presents, he
reflects upon the plenitude of its delights, and mingling reli-
gion with his mirth, ascends in holy meditation to the idea of
a kind Creator, and even to the glories of a future world.
However, life is liable to many accidents that tend to cut
short the thread by which we hold it. Wounds, diseases,
poisons, are often fatal to the life of man, as well as to other
animals. A violent blow on the temples will extinguish life
in an instant. Plague, pestilence, and famine, will speedily
produce the like effect; and a few drops of concentrated prus-
sic acid introduced into the animal circulation will cause almost
immediate death. But if the individual should fortunately
escape all fatal accidents, still a term will come beyond which
life cannot be protracted; still it will be worn out at last by a
natural and gradual decay.—Observe its progress in the plant,
and the symptoms of approaching dissolution. ‘The root re-
fuses to imbibe the nourishment afforded by the soil. The
juices are but feebly propelled, and their assimilation effected
with difficulty. The bark becomes thick and woody, and co-
vered with moss or lichens. ‘The shoot becomes stunted and
* Psalm Ixy,
diminu-

134 Rev. P. Keith on the Conditions of Life.

diminutive; and the fruit palpably degenerate, both in quantity
and quality. ‘The terminal branches fade the first, then the
larger branches, and then the trunk and root. The vital
energy of the fabric languishes, and is at last totally extin-
guished; and the plant, now exposed to the chemical action
of surrounding substances which it cannot any longer resist,
withers and dies away, presenting to the eye a decayed and
rotten appearance, and crumbling into the dust from which it
originally sprang.—Observe its progress in the animal, and
you will find that the symptoms are of a similar character.
It has been said indeed of man, that it is the body only, and
not the mind, that suffers decay and death. But it is evident
that the mind is liable to decay and to death as well as the
body. If the organ perishes, its function must inevitably
perish. Ifthe brain dies, its function—mind—must cease. As
well might you expect that digestion should continue when
life has left the stomach, as that mind should continue when
life has left the brain. If the eye becomes dim, and the ear
dull of hearing, and the palate incapable of tasting, and the
nostril devoid of smell; so the memory becomes weak, the
judgement erroneous, the understanding embarrassed, the will
slow in its decisions, and the organs that are subject to it slow
in their obedience; inducing “second childishness and mere
oblivion;” and exhibiting man in his state of dotage “sans
mouth, sans teeth, sans eyes, sans every thing.” It is but a
step further to the total extinction of life, and cessation of all
living function; that is, in other words, to the death of both
the body and the mind.

During life, all was activity, all was vital, or spontaneous
motion, all was the exercise of organic function. In plants,
absorption, assimilation, and distribution of fluids, with growth
and development of parts. In animals, prehension, digestion,
and assimilation of food; with growth, loco-motion, intellec-
tion; and in man the faculty of speech ;—all referable to the
agency of that subtle, invisible, and incomprehensible some-
thing called life, which counteracts and controls mechanical
and chemical agencies, and converts them to its own purposes.
—If I move my arm from the pendant position, and raise it
to a horizontal or upright position, the agency of gravitation
is counteracted. If the materials that compose the living
fabric do not tend to putrefaction, the agency of chemical affi-
nities is counteracted. But in death there is no longer any
resistance opposed to these agencies, no living action, no spon-
taneous motion, no exercise of organic function: in short,
the fabric is no longer a living system. Chemical and me-
chanical agencies affect it merely, exerting themselves in their
full strength, and reducing it, sooner or later, to the panera

an

Mr. Innes’s Correction in the Nautical Almanac for 1833. 135

and elementary principles out of which it was originally
formed.

Sleep has been said to be the image of death. But it is
only a transient suspension of some of the functions of life.
The exercise of function fatigues the organs, and hence they
require a period of repose. Such is sleep, which lasts only
till the fabric is recruited. NHybernation might be said to
be the image of death also; but it depends entirely on tem-
perature. When the temperature sinks to a given degree,
hybernation begins; and when it rises again to the same degree,
the exercise of function is resumed. But if death once super-
venes, its dominion is perpetual; and its empire not to be es-
caped from. It is “the undiscovered country from whose
bourn no traveller returns’—the “‘cheerless night that knows
no morrow.”

Omnes una manet nox,
Et calcanda semel via lethii— Hor. Ode 28. lib. i.

that is, as regarded in a physiological light; for the morning
that is yet to “dawn on the night of the grave” we are not
taught to look forward to as a consequence resulting from
the established order of things, but as an event emanating
from the fiat of the Almighty*.

Thus the phenomena of life and of death are plainly and
palpably distinct. ‘They are opposite, and irreconcilable, and
cannot be mistaken. Life composes, death decomposes; life
rears a fabric, death destroys it; where life extends, the inte-
grity of the fabric is maintained; where life ends, decomposi-
tion with putrefaction begins. Such is the victory achieved
by death, and the inevitable doom of every thing that lives.

Ruckinge Rectory, Kent, April 26th, 1830. P. Keiru.

XV. On the Statement in the Nautical Almanac for 1833, of
the Time of Beginning of the Solar Eclipse of the 16th of
July in that Year; together with the correct Times of that
Eclipse, computed for Greenwich. By GrorceE Innes, Esq.

To the Editors of the Philosophical Magazine and Annals.
Gentlemen,

JN the Nautical Almanac for 1833, I find the beginning of

the solar eclipse of the 16th July, stated to be at 16" 5™
It appears to me probable that the units and fraction of a
minute have fallen out in printing. About four years ago, I
calculated the times of the above eclipse for Edinburgh and
Greenwich Observatories, using Delambre’s tables of the sun,

* (John y. 28, vi, 39, 40, Rom. vi. 23, 1 Cor, xv. 36, 44, 51,—Eprr.}
and

136 Further corrections in the Nautical Almanac for 1833.

and Damoiseau’s Lunar Tables of 1824. The times which I
obtained for Edinburgh were inserted in Professor Jameson’s
Journal for October—December 1828 ; and the following are
the results for Greenwich.

According to Burckhardt’s tables the times are about 19°5
seconds earlier. Bessel’s corrections of the Solar Tables had
not reached me when I made the computations.

Mean time. Apparent time.

D HH. M. Ss. H. M. s.
The eclipse begins, July16 17 4 5:8 16 58 23:0
Greatest obscuration — — 17 55 4% 17 49 21:2
App' ecliptical conj” — — 17 58 16°6 17 52 33°6

End of the eclipse .... — 18 49 21:9 18 43 38:7

Digits eclipsed at greatest obscuration, 8°" 47! 48!-3 on the
north part of the sun’s disc.
The moon will enter the sun’s disc on the west limb at
37° 12’ 20” from his vertex, in reference to the horizon.
I am, Gentlemen, &c.
Aberdeen, April 27th, 1831. GrorceE INNEs.

XVI. Errata in Schumacher’s Ephemeris of the Distances of
the four Planets Venus, Mars, Jupiter, and Saturn, from the
Moon’s Centre, &c. for 1833, published by the Admiralty. By
A CorRESPONDENT.

“ee following errata have been kept back for some time,

and would have been reserved for publication in the

Nautical Almanac for 1834, but that the advantage resulting

from the discovery of them would be diminished by the delay.

Page.

“ fo} i il

9. Sept. 17. xxi"... for 105 515 read 100 5 15
17. May 2. ——..... -— 88 44 29 88 44 29
18. May Bl eeiK eee -— 69 339 —— 109 2 39
46. Jan. 22. Log.dist. — 0°95266 —— 0:05266

Bl. June Qs. ccccccccenes ——) 5D AD’ 4. V——— — 54842 de
56. November 1. November 30. Dec. S.

GS MINCE Disseessse odes jor 35 6 20°2 — 3. 62032
66. September 20. ... — 9 42 37°7—— 9 22 37°7
68. November % ...... — 12 33 53:°9-—— 12 43 53°9
75. June 30.

76. July 31. Hrs Ni

77. August 31.

88. July 19. Log. dist. for 0°63651 —— 0'69651

98. May $1. nh id 55110. No. —et DEB bd LON
99. June 7. Log. dist. — 6:97029 —— 0'97029
110. May Llescrcccceeee —= 322 2646 —— 322 27 46

Chislehurst, July 1, 1831, )
XVII. On

wa 7iAl

XVII. On the Theory of Differences, by SAMUEL SHARPE,
Esq. F.G.S.*

Prop. LPO interpolate a maximum or minimum in a
series, by means of the theory of differences.

This perhaps may be useful on many occasions, in practical
astronomy, when the observer has a series of altitudes at equal
intervals, without all the data, such as time and latitude, ne-
cessary for the more rigid formula. As for instance; From
a series of altitudes near the meridian, to find the meridional
altitude and approximately the time of transit; which is a far
more accurate method than that commonly used by sailors,
of watching the sun’s ascent till it becomes stationary, which
gives the time of noon with extreme inaccuracy, and the me-
ridional altitude single and uncorrected by others.

And again; From a series of declinations near the solstice
to determine the solstitial declination.

To explain the signs make

Quantities First Second Third
observed. | Difference. | Difference. | Difference.

and w’ and /' the quantities sought.
: By a well-known formula in the theory of differences, we
ave

rAd (pl 4 7 aa 1__9
ut Aly =a =ut+ = Aut eB Atu+ Ee aeame:
and by expanding and rearranging, [1]

AN us (4 Amu Abu Adu he? baw A’a ILAtuy h (Aru Aru
Bary Ae a ts hea et BTN

hit Atu
Aa [2]

which for convenience we will write
Als
Fie (3)

and if we consider this value of « as a maximum, we may
make two equal values, one on each side of it; viz.

! ! I !
nau (“P04 (2) + (“F*)c4 (A) > 4

* Communicated by the Author.

N.S. Vol. 10, No, 56. Aug. 1831. 4 ly and

}! ji h'8
W=u+5-A+—5,B4+5-C+4

138 Mr. S. Sharpe on the Theory of Differences.

and
h'—a h'i—a h'—a h’—a
u=u+( . )a+( : ) B+ ( = \c+ ( 5 ) Dis]
by expanding the binomials and subtracting one equation from
the other, we have
QaA 4ah'B . 6ah?+2a° 8ah*+ 8a? h!
Cas: Lae!

—

then dividing by =, and, as a may be infinitely small, re-

jecting those terms which then involve a,
‘ Aa }! B jl C Ae
O=A+—-2B+ 558 aby 5 wae Jee
whence by Newton’s method of reversing a series, we have

h! A 8 A?C A’
Ss at gE hg eee
!
when w’ is a maximum; and with this value of = we shall
know from our original equation the value of w! as a maximum.
As an example I shall take the following declinations of
the sun from the Nautical Almanac for 1829.

June 19 | 23°26! 30”

43!
20 | 23 27 13 — 24!
+ 19 — }
21 | 23 27 32 ‘ — 25 5 + 1"
22 | 23 27 26 $i — 25

23 | 23 26 55

in which A = +544, B= —11", C= —0"38.
D being +005 may be neglected.
U

es = 2°46 — 0°31 + 0"-24, and h’ = 2 days 9° 15",

being three hours wrong; and
ul = 130" — 62"-8 — 49 4+ u = 23° 27! 33!"3,
being 0'*5 wrong.
These results are as accurate as could be expected, consi-
dering the original values of « do not contain tenths of a se-

!
cond; and if the value of = had been known from other

data, the resulting value of u’ would have been exact.
Prop.

Mr. S. Sharpe of the Theory of Differences. 139

Prop. I1.—To determine the point of contrary flexure in a
curve; or to interpolate a term in a series, such that its second
difference is = 0 by means of the theory of differences.

Instead of w+, as in the former Proposition, we now have
u+u : :
Ut Ms = yl, Consequently by expanding the three equations
[3] [4] and [5] we have
3a°h! 16h” a? + a*

BS Lae NAESR

a

whale a’ Oe “We
Dividing by 77> and rejecting the terms then containing 4,

}! hi?
we have o=B+—>-3C+-—, 6D

Le, Bp, GD
pay ae 27 C
and hence we have in equation [1] the value of w’.

By this proposition and a series of altitudes of a star in the
east or west, we may deduce the time of its passing the prime
vertical, and its altitude when there.

Hence if P be the hour-angle at the pole,
L, the latitude of the place,
A, the altitude on the prime vertical,
D, the star’s declination,

; cos A : sin D
sin P= con Ti and sin L = aa
Prop. I11.—From a set of observations made at equal in-
tervals to obtain one more correct, corresponding to the mean
of the times. Or it may be stated, To correct the mean of a
set of observations by help of the theory of differences.
Let there be seven observations; then

(See Baily’s Tables.)

+ A®*u

u+3Au + SA*u + A®u

u+4Au + 6A?u + 4Ar%u
u,=u +5AuU + 10A2u + 10A%u
te=u+6Au + 1l5A2u + 20A*%u

neglecting the higher differences.

Now the mean of these quantities gives us
U, = t + S$Au + 5A*u + SAU,
which is evidently too great by 2 Aru + 4 Abu.
T2 Hence

Rg
hu udu ua
S
ae
ro
>
S

140 Mr. S. Sharpe on the Theory of Differences.

Hence, with seven observations,
uw; = mean of observations —2 mean of second differences ,
and thus we may construct the following table:

Number} Mean Quantity

of Obser-| of the eaueht Value of Quantity sought.
vations.| ‘Times. ae
1 |m “a ... | The observed quantity.
9 |m+ a ay Mean of observation.
2
3 |Im+h uy Do. —1 mean of A?
3h d
4 |m+ Us ses | Do. — mean of A®
3} 2
Bay NT A, Veg. vane Do. — mean of A?
5h 2
Ge tge ls Do. —3 mean of A®*
7 |Im+3h| ws o Do. —2 mean of A®

Remark,— This proposition may be used on all occasions
to which the rule is applicable, that “ by a single observation
is meant the mean of a series,” (see Requisite Tables, Baily’s
Tables, &c.) and in particular in learning the time from a
single altitude observed ; when we consider that many persons
have occasion to learn the time, who have neither instrument
to observe a transit, nor leisure to take equal altitudes.

Prop. 1V.—From an observed place of the moon, and four
given places in the Nautical Almanac, to determine the time
at Greenwich.

This is I believe not in general solved analytically, but syn-
thetically ; thus,

ist, Assuming the time at Greenwich, by help of the differ-
ence of longitude known approximately.

2ndly, By the theory of differences determining the moon’s
place by equation {1}.

I lpi
Vale 5 Fau peeeh A?u +
3rdly, Thence correctly the assumed time.

This equation is computed more conveniently by means of
tables of the coefficients of A, A® and A’, but if such tables are
not at hand would be more easily computed in the form [2].

Aru A*) as on) + (“).

h! (h!—h) (h! —2h)
Tae. ee

q +73 1 a a a ie a a

. i!
Au= F(ax- oe og
But

Prof. Airy’s New Optical Experiments. 141

But it would be more accurate to solve the proposition by di-
rect analysis; and writing this last equation as before,

hl? he

—- C.

}!

h h?
By reversing the series, we have
Ht hu (ay HB ak bar
Sih) Ae Mow A Baia)
Remark.—The rule given in the Nautical Almanac is ac-
cording to equation [1], but upon the supposition that the
tables are not accurate beyond A’u, and consequently that

Aeu+ A*u,

A*u ought to be = 0, and therefore 2 is used in-
stead of A®u: thus
h' ih —h) 7 KRut+A ru
ES = Aut a = ( Seta but now that

the tables are sufficiently accurate it would be better to use
Aru.

And hence it seems to me that Mr. Baily has committed an
oversight; for wishing to introduce A*w, he has still employed

9 2
Aetan, which was used only on the supposition that A%u

ought to be neglected, and has written
}! (h'—hy A? ut A®uy hi (h'—h) (h'—2 hy
2h ( 2 ) + 6A at,
corrected in the Errata to
Bh —h)/ Aut A2u,\ . #! (h!—h) (h!—3 h)
oT 3 )+ 6H atu
instead of equation [1].

i!
ul =u+ >- Aut

Al
wut > Au+

XVIII. New Optical Experiment by Professor Airy.

[We are indebted to the kindness of a Cambridge friend for
the following account of some new optical experiments made
by Professor Airy: it announces some remarkable dis-
coveries, which have an important bearing in the verifica-
tion of the undulatory theory of light.)

AN instructive variation of the experiment of Newton’s co-
loured rings (suggested by the consideration of Fresnel’s
formula for the intensity of reflected vibrations) has lately
been made by Professor Airy. When a lens is placed on a
plane

142 Prof. Airy’s New Optical Experiments.

plane glass it is well known that a set of rings is seen whose
centre is remarkably black: and it is indifferent whether com-
mon light or polarized light be used, the only difference made
by the latter being that when the plane of polarization is per-
pendicular to the plane of reflection, and the angle of inci-
dence is the polarizing angle, the rings disappear; but on
altering the angle of incidence either way, the rings still ap-
pear with the centre black. If, however, a lens is placed on
a metallic surface, and the incident light is polarized in the
plane perpendicular to the plane of incidence; while the angle
of incidence is small, the centre of the rings is black; when it
is equal to the polarizing angle of the glass the rings disappear
(though there is still copious reflection from the metal): then
on the smallest increase of the angle of incidence the rings
are seen with their centre white, and they continue so till the
angle of incidence = 90°. It is indifferent whether the light
is polarized before or after reflection; and a remarkable effect
may be thus produced: if common light is incident at an angle
greater than the polarizing angle, the rings have a dark
centre; but on placing a plate of tourmaline (with its axis
perpendicular to the plane of reflection) between the eye and
the lens, the rings are seen with a bright centre. The Pro-
fessor conceives that the whole of these experiments are in
the highest degree favourable to the theory of undulations
with transversal vibrations as given by Fresnel, and to the idea
(which is a necessary part of that theory) that polarization is
not a modification or physical change in the light, but a reso-
lution of its vibrations into two sets, one in one plane, and the
other in the plane perpendicular to the former, one of which
sets sometimes is suppressed and sometimes describes a dif-
ferent path. The last experiment (where the character of the
rings is changed after they are formed) appears almost de-
cisive of this point. From the manner in which the rings
alter when the tourmaline is turned, the Professor infers that
the phases of the vibrations in the plane of reflection are more
accelerated by reflection at metallic surfaces than those of the
vibrations perpendicular to the plane of reflection. The dark
centres, it is to be observed, are never so dark as when the
lens is placed on glass; and the bright ones are never very
bright.

The result of the following experiment, like those of the
former,was anticipated by theoretical considerations, and shows
the clearness with which, by Fresnel’s theory, the effects of
modifications can be traced whose very nature is inexpressible
on any other theory. In the common polarizing apparatus,

plane-

Geological Society. 143

plane-polarized light is incident, and the light emerging from
the interposed crystal is resolved into two streams of plane-
polarized light (by the analysing plate), of which one only is
transmitted to the eye. It is known that circularly or ellipti-
cally polarized light will, if incident on the crystal, form rings ;
but it has not been remarked as a general theorem, that rings
will be visible if the analysing plate be so constructed as to
resolve the light emerging from the crystal into any two kinds
of light, of which it suppresses one and transmits the other to
the eye. Now by means of Fresnel’s rhomb, or (imperfectly)
by a film of mica, the analysing plate may be made to resolve
the emergent light into two circularly-polarized rays, one of
which it transmits to the eye, while the other is suppressed.
Supposing the light to be thus analysed and supposing the
incident light to be circularly polarized, theory gives this
result: the tint will depend only on the gain or loss of the
extraordinary on the ordinary ray: there will be no brushes:
the appearances will not alter as the crystal is turned about
the incident ray. These conclusions are completely supported
by experiments on uniaxal and biaxal crystals and unan-
nealed glass. Iceland spar, for instance, shows rings without
brushes: nitre, &c. exhibit the lemniscates in their whole ex-
tent without any interruption.
Cambridge, July 25, 1831.

XIX. Proceedings of Learned Societies.

GEOLOGICAL SOCIETY.

June 8th,— A LETTER was read, from Joshua Trimmer, Esq.

to the Rev. Dr. Buckland, V.P. G.S. “On the diluvial
deposits of Caernarvonshire, between the Snowdon chain of hills and
the Menai strait, and on the discovery of marine shells in diluvial
sand and gravel on the summit of Moel Tryfane, near Caernarvon,
1000ft above the level of the sea.”

The object of this paper is to point out evidences of extensive dilu-
vial action in that part of Caernarvonshire which lies at and near the
N.W. base of the mountains of Snowdonia. This district is traversed
in adirection from N.E. to S.W., and nearly parallel to the mountain
chain, by two remarkable beds of roofing slate, well known by the
name of Penrhyn Slate, dipping usually to the S.E. at a considerable
angle, and extending along a series of hills of moderate elevation,
between the Snowdonian chain and the Menai strait. Great part of
the surface of these hills, and of the still lower ground between them
and the Menai, is so covered by accumulations of drifted gravel, sand
and clay, that the slate is seldom accessible, without first penn

own

144 Geological Society.

down through a thick bed of this diluvium. It occurs, not only in the
valleys, but on the sloping sides and summits of hills, sometimes en-
tirely covering the hills, at others accumulated around small project-
ing crags. It is spread indiscriminately, and with little reference to
the rivers that now intersect the country: its greatest observed thick-
ness is about 140ft.

A large proportion of this gravel is composed of pebbles and blocks
of various sizes, derived from rocks that occur in Caernarvonshire ;
many of these are less rolled than pebbles of another class that are
mixed with them, and which have come from a greater distance, and
must have been drifted upwards by some violent inundation, in a
direction contrary to that of the rivers which descend from Snowdonia
into the Menai. Among these pebbles are several which can be iden-
tified with the granite, sienite, green-stone, serpentine and jasper of
Anglesea: other granite pebbles agree with no rock in Anglesea or
Wales, and resemble the granite rocks of Cumberland; some may
have come from Ireland or the S.W. extremity of Scotland.

There are also chalk flints, which can have come from no nearer
source than the chalk of the county of Antrim.

This diluvium occurs in great thickness in the lower region of the
valley of the Ogwen, usually from 60 to 100ft; forming its bed, and
often occupying both sides of the valley through which it flows. These
sides, for a considerable distance, afford indications of having received
their last form from the bursting of a lake higher up in the valley of
the Ogwen.

Shells, and fragments of shells, like those on the shores of the ad-
jacent sea, are reported by the workmen to have been found in the
sand and gravel at an elevated spot near Moel Taban, on the right
bank of the Ogwen, nearly opposite the quarries of Penrhyn. Mr.
Trimmer did not see them here ; but on the summit of Moel Tryfane,
on the south of Caernarvon, towards Bethgellert, in a sinking made
through sand and gravel, in search of slate, at about 20ft below the
surface, he found marine shells in a bed of sand; they were for the
most part broken, resembling the broken shells on the adjacent beach;
when dry, they adhere to the tongue: the fragments are too indistinct
to identify species; the genera Buccinum, Venus, Natica and Turbo
occur among them. Mr. Trimmer found similar broken shells also
in the diluvium of the low cliff near Beaumaris.

Beneath the diluvial deposits of this district, when the surface of
the slate-rock is newly laid bare, it is found to be covered with
scratches, furrows and dressings, like those observed by Sir James
Hall on the summit of the Costorphine and other hills near Edin-
burgh. These furrows and dressings were noticed several years ago
by Mr. Underwood : they are referred to the action of the diluvial
currents which overspread the country with gravel: some of the
larger blocks amid the gravel have also deep scratches upon their
surface.

Where the diluvium is argillaceous, the surface of the subjacent
slate has been so protected by it, as to remain sound and fit for use

as

Zoological Society. 145

as roofing slate up to its line of contact with the incumbent clay ;
but where the diluvium is of sand or gravel, admitting ready access
of water through it to the subjacent slate rock, the slate is often in
a shattered state, and bent and decomposed to the depth of many feet
below the line of contact.

At the close of this Meeting, which terminated the Session, the
Society adjourned till Wednesday the 2nd of November.

ZOOLOGICAL SOCIETY.
May 31, 1831. _N. A. Vigors, Esq. in the Chair.

At the request of the Chairman, Mr. Gould exhibited a specimen
of the male of the Urogallus medius ; the Tetrao hybridus of Gmelin
and Dr. Latham, and the Tetrao medius of M. Temminck.

Mr. Yarrell observed that this individual, with one other example of
the same rare species, also a male, was found among a considerable
number of the Tetrao Urogallus of both sexes, brought from Nor~
way by a boat partly laden with lobsters for the London market.
Some of the older writers considered this bird to be a hybrid pro-
duced between the Wood Grouse and the Black Grouse, and had
named it accordingly: modern authors have, however, established
its distinction as a species; and the female and its egg are now
known. Notwithstanding the general resemblance between these
two large Wood Grouse they are decidedly and very obviously dif-
ferent. Inthe Tetrao medius the beak is black ; the shining fea-
thers on the front of the neck and breast are of a rich Orleans-plum-
colour ; and of the 18 feathers of the tail the outer ones are the
longest. In the Cock of the Wood the beak is white; the feathers
on the front of the breast are of a dark glossy green ; and the centre
feathers of the tail are the longest.

The organ of voice in the Tetr. medius is peculiar. The trachea
of this bird and that of the Tetr. Urogallus were exhibited ; and Mr.
Yarrell pointed out that the trachea of the Tetr. medius, eleven
inches in length, has no loose fold, like that of the Tetr. Urogallus,
but descends in a straight line to thelungs. From the thyroid car-
tilage two pairs of muscles follow the course of the trachea, one pair
firmly attached to the trachea itself, the second pair suspended
loosely in the cellular tissue. Both these pairs of muscles, after an
extent of eight inches, are lost in a membranous expansion, form-
ing a sheath, which invests the inferior fourth portion of the trachea,
and from which sheath one muscle only on each side is sent off,
immediately above the bifurcation of the bronchia, to be attached
to the inner surface of the sternum.

The stomach is a true gizzard of great muscular power, and the
intestines and ceca, as in all the Grouse tribe, are very long: the
ceca in the present instance measured each three feet in length.

There is reason to believe that this bird inhabits the Apennines
as well as the more northern localities assigned to it. Mr. Fox in
his ‘ Synopsis of the Newcastle Museum’ quotes a note of the late _
Mr. Tunstall which states that “he knew some old Scotch gentle-
men who said they remembered, that when young, there were in
Scotland both the Cock of the Wood, and the Tetr. hybridus.”

N.S. Vol. 10. No. 56, Aug. 1831. U Mr,

146 Zoological Society.

Mr, Yarrell availed himself of the opportunity to state that the
hybrid Grouse of White’s ‘ Natural History of Selborne’ is believed
to be a young black Cock, having nearly completed his first moult.
He added that he was indebted to Mr. Sabine for the information
that the Tetr. rupestris of Pennant’s ‘Arctic Zoology’ has been killed
in Perthshire, and that the specimen is preserved in the collection of
Lord Stanley, the President of the Society.

At the request of the Chairman, Mr. Martin referred to the notes
of the dissection of a specimen of Testudo Greca which he had laid
before the Committee on the 26th of April, and stated that the
correctness of these notes had been subsequently confirmed by the
examination of another individual of that species, in which he had
observed the same lengthened form of stomach ; similar intestines ;
and a cécum agreeing with that previously described. The urinary
bladder also corresponded in form and size. The trachea bifurcated
in the same manner; and the bronchi@ had the same remarkable
sigmoid flexure, and were furnished with the compressing muscle
which he had before noticed.

Mr. Owen remarked that he had ascertained the existence of a
cecum in another species of Tortoise, (Emys concentrica, Leconte,)
which he had recently dissected.

The preparation of the cecum of the Testudo Greca having been
laid upon the table, it was pointed out that the part so termed in
this instance consisted of a pouch formed by the oblique insertion
of the small into the large intestine, the upper end of the latter
being dilated as in the human subject into a cecum caput coli: but
that it by no means corresponded with the ceca of birds, and might
almost be regarded as wanting when contrasted with the develope-
ment of the same part in some of the Ophidian Reptiles, as in the
genera Python, Boa, &c.

A living individual, apparently referable to the Gulo barbarus, L.,
was exhibited. It was presented to the Society by Edmonstone
Hodgkinson, Esq, of Trinidad, who describes it as being ‘ playful
and gentle, although easily excited, and very voracious. It is ex-
ceedingly strong, as is indicated by its shape ; and it has the same
antipathy to the water as acat.” Mr. Hodgkinson suspects that it is
a native of Peru. He obtained it inVenezuela, where it was presented
to him by the President, General Paez. The name he received with
it was ‘the Guache ;’ but this appellation, it was observed by Mr.
Bennett, was probably erroneously applied to the present animal,
belonging rather to the Coati, the orthography of which is variously
given as Coati, Couati, Quasje, Quachi, and Guachi. The latter
form occurs in the ¢ Personal Narrative’ of the Baron Von Hum-
boldt, where it evidently refers to a nocturnal species of Nasua.

The form and general appearance of the animal were remarked
to be altogether those of a Mustela, to which genus it is probable
that it should be referred, together with the typical Gulo barbarus.
A specimen of the latter was placed upon the table, from which the
living animal was shown to differ by the absence of the large yellow
spot beneath the neck : a remarkable distinction in this group, but

on

Zoological Society. 147

on the occurrence of which, unless confirmed by several specimens,
it was considered improper to propose regarding it as a distinct
species.

A stuffed specimen and a skeleton of the Acouchy (Dasyprocta
Acuschy, lllig.) having been laid on the table, the following notes
on the anatomy of that animal were read by Mr. Owen.

«‘ The subjects examined were the male and female <Acouchies
which were exhibited to the Committee on the 23d of November
last by Mr. T. Bell, in whose possession they remained alive till
May, when they both died in one of the remarkably cold nights of
that month.

« The following circumstances were common to beth animals.

«On laying open the cavity of the abdomen the intestines were
found to be generally adherent to each other and to the parvetes of
the cavity, arising from recently effused 1 mph: they were also of
an unusually dark colour, owing to their contents.

« The stomach consisted of a simple cavity, of a full oval shape,
without any contraction between the cardiac and pyloric portions.
The esophagus had a course of nearly an inch within the abdomen
before its termination. This is acircumstance worthy of notice, and
which occurs in a marked degree in most of the Rodentia. The
inner cuticular membrane of this part terminated abruptly at the
cardia. The villous coat of the stomach was without ruge, and of
a gray colour, whilst that of the intestines immediately beyond the
pylorus was stained of a very dark colour; showing that the pylorus
had acted as a very effectual valve.

« The ca@cum was of a capacious size, and had the same sacculated
appearance as in the Guinea-pig ; it occupied the whole of the iliac,
lumbar, and part of the hypochondriac regions of the right side,
and was disposed in a sigmoid form ; the colon at its commencement
followed the curvatures of the cecum, and was attached to it by a
continuation of the peritoneal membrane ; about six inches from the
caecum the feces became divided into pellets. The cecum itself was
filled by a black tough pultaceous mass, of a slightly acid odour ;
and the same coloured matter, but in a more fluid state, was con-
tained in a greater or less quantity throughout the small intestines.

«The liver consisted of four principal divisions and a lobulus
Spigelu ; the gall-bladder was imbedded in a cleft in the right di-
vision, and contained a small quantity of dark-coloured watery fluid.
The pancreas consisted of two separate lobes. ‘The spleen was of a
very dark colour, pointed at the lower extremity, and about one
inch and eight lines in length.

« The kidneys were prominently situated in the hypochondriac
regions, the right being nearer to the diaphragm by one half its
length than the left. Each was about one inch in length and con-
globate. The supra-renal glands were of an oval shape six lines by
two in their dimensions, situated anterior to the upper extremities
of the kidneys, but unattached to them ; the right closely adhering
to the vena cava inferior, the left to the vena emulgens of its own side.

« The viscera of the chest, like those of the abdomen, presented
traces of general inflammatory action,

U2 «The

148 Roological Society.

“‘ The lungs were divided into three lobes on the left side and
four on the right, the fourth being the dobulus medius seu impar,
occupying the space between the pericardium and diaphragm. The
heart terminated obtusely, with a slight indication of a double apea.
The aorta gave off the carotids and the subclavian arteries by a
common trunk.

“‘The rings of the trachea were incomplete, their extremities
being separated behind by a small space. ;

“The cricoid and arytenoid cartilages were of large size as com-
pared with the thyroid ; the apices of the latter were continued into
each other; the chorde vocales were very short but distinctly
marked, and with a small sacculus on each side. There were no
cuneiform cartilages ; the epiglottis was triangular with the apex
prolonged into a small mucro. Viewed from above, the aperture of
the /arynz was circular, and was directed from behind forwards.
The tongue was subacuminate, minutely papillate above, with a
middle longitudinal line extending half an inch from the tip: it had
no elevated posterior part as in the Guinea-pig, Beaver, Hare, &c.
but at the root of the tongue there were numerous elongated cuti-
cular processes, and on each side of the Sauces a fold of membrane,
whose action is evidently to obviate too rapid transmission of the
food through the fauces.

“In the male the testes were found within the abdomen, with the
extremity of the epididymis projecting through the abdominal ring;
but as the whole gland could be pushed with ease through the
aperture, the Acouchy cannot be considered one of the true festi-
conda. The levatores penis were very distinct, arising from the upper
part of the pubes and terminating in tendons which ran along the
convexity of the dorsum penis to the glans.

“In the female the ovaries were found of very small size and
apparently in a scirrhous state.

*« In both there were small clavicular bones, about the thickness
of a small pin, and eight lines in length, which were connected by a
ligament of the same length to the sternum. Their office appeared to
be to afford a fixed point of attachment to a muscle arising from
the transverse processes of the cervical vertebre analogous to the
levator clavicule in Apes, and to give origin to part of the deltoid,
by which it is better adapted to draw forwards the humerus.”

The following notes on the anatomy of the Thibet Bear ( Ursus
Thibetanus, F, Cuv.) were also read by Mr. Owen. The subject
examined was a young individual which had lived about two years
in the Society’s Garden.

‘An extensive abscess was found under the scapula, which ap-
peared to have communicated with the cavity of the chest ; but the
lungs, heart, and liver having been removed before the animal came
under my hands, I had no opportunity of ascertaining the connec-
tion it had with diseases of those parts.

“The length of the animal from the nose to the root of the
tail was 3 feet 4 inches: that of the intestinal canal 33 feet. Every
part in the abdomen was loaded with fat. The stomach resembled
the human in shape, and had a well marked contraction nen

the

Soological Society. . 149

the cardiac and pyloric portions; the muscular parietes of the
latter were half an inch thick; and, as in the Bears generally,
had a tendinous appearance externally on each side. The intes-
tines were simply villous internally. The biliary and pancreatic
secretions entered at a distance of four inches from the pylorus.
There were four or five longitudinal ruge@ in the terminal six feet
of the intestinal canal; and the diameter was smallest at this part.
There was no cecum, nor any valvular apparatus in any part of the
intestinal canal.

«“ The anal follicles were two in number, of the size of hazel-nuts.
One of them was filled tensely with a yellowish-brown cheesy sub-
stance, which had a strong acetous odour; the contents of the other
were of more fluid consistence, but had the same odour ; the excre-
tory orifice was just capable of admitting a common probe; the
lining membrane was thin, of a white colour, but not so distinctly cu-
ticular as is commonly found ; it resembled more the lining mem-
brane of the urinary bladder. Each follicle was surrounded by the
fibres of a muscle which was inserted into the crus penis.

“The spleen was of a trihedral shape, 7 inches in length, 13 in
breadth, of a light mottled pink colour and granular texture ; the
splenic vein contributed to form the vena porte in the usual manner.
The pancreas was of about the same size as the spleen ; but the py-
loric portion bent at right angles with that which passed behind the
stomach.

« The kidneys consisted each of about thirty lobules. The ureters
terminated separately but close together at the neck of the bladder.
The urinary bladder was a narrow oblong bag, and about half an
inch of the urachus still remained permeable from the fundus
vesice.

« The tungue was long, broad, and thin at the extremity, with the
edges turned down. On the upper part was a longitudinal mesial
groove extending four inches from the tip. The surface was uni-
versally papillose, and with the simple papile were intermixed
numerous small white petiolate papille. Ata distance of five inches
from the tip there were eleven large fossulate papile, forming two
sides of a triangle whose apex is towards the epiglottis. Nearer to
the epiglottis were numerous cuticular pointed processes directed
backwards. The lytta, or worm of the tongue, was 5 inches in
length, about the thickness of a crow quill, and bent upon itself
near its middle part : it had fibres of the linguales muscles inserted
into its anterior extremity, but laid loosely for the rest of its extent
among the cellular texture in the interval of the linguales and
gore lossi. The velum palati was terminated at its lower margin

a short bifid woula, the azygos wvule consisting here of two quite
distinct muscles.”

A pair of the middle tail-feathers of the Phasianus Reevesii,
Hardw. and Gray, ( Phas. veneratus, Temm.) were exhibited; for
one of which the Society is indebted to the liberality of John Reeves,
Esq., of Canton. ‘These feathers measured each about five feet six
inches in length. The bird from which they were obtained is the

first

150 Intelligence and Miscellaneous Articles.

first individual of this rare and magnificent species ever brought
alive to Europe. It was presented to the Society by Mr. Reeves,
and is now living at the Garden in the Regent’s Park, A second
individual died on the passage to England.

XX. Intelligence and Miscellaneous Articles.

GENERAL SCIENTIFIC MEETING AT YORK.

f Nets following notice has been circulated by the Council of the
Yorkshire Philosophical Society, and we are happy in com-
plying with their request to give it publicity in our pages.

«“ The Council of the Yorkshire Philosophical Society having re-
ceived intimation from men of scientific eminence in various parts
of the kingdom, of a general wish that the friends of science should
assemble at York during the ensuing autumn, we are directed to
announce that the Society has offered the use of its apartments for
the accommodation of the meeting, which will commence on the
26th of September, and that arrangements will be made for the per-
sonal convenience of those who may attend it. It will greatly faci-
litate these arrangements if all who purpose to come to the meeting
would signify their intention as early as possible (by a letter, post-
paid) to the Secretaries.

« WILLIAM VERNON Harcourt, Vice-President.
« Won. Gray, Jun,
¢¢ Joun PHILLIPS,

“ Yorkshire Museum, York, July 22, 1831.”

} Secretaries.

ON THE RAPID FLIGHT OF INSECTS.

In passing along the Manchester and Liverpool railway, at a
speed of about twenty-four miles an hour, ascertained by a stop-
watch, I observed one of the smaller humble-bees, I think the Apis
subinterrupta, flying for a considerable distance and keeping pace
with the train apparently without the slightest effort; in fact, the
little traveller was going at a rate far more rapid than ours, for its
accompaniment was not ina straight line but in that well-known
zigzag mode of flight observable when these insects are hovering
from flower to flower in search of food. Several house, blue-bottle,
and horse flies were also repeated visitors : our rapid motion seemed
to have no manner of effect upon them, for when it suited their pur-
pose they darted onwards, for a few feet or yards or balanced them-
selves steadily over any given point; though in an instant, whenever
either their efforts relaxed, or they thought it expedient to part
company, they were faraway inour rear. I should observe, more-
over, that the wind at the time was blowing obliquely against us
with a current of such strength, {that I] occasionally had some
difficulty in keeping my hat on. Under all circumstances, there-
fore, of the wind’s opposition and their irregular motion, I consi-
dered that the locomotive powers of these insects could not be well

less

er

Intelligence and iscellaneous Articles. 151

less than from thirty to forty miles an hour. Compared with the beau-
tifully arranged muscular powers of these minute beings in the crea-
tion, how insignificant are those which science, with all its advan-
tages, has hitherto been able to accomplish by mechanical means!
D. T.

PROCESS FOR PREPARING HYDROCYANIC ACID.

Mr. Thomas Clark of Glasgow has published an account of a
method of preparing this acid, in the Glasgow Medical Journal,
from which the following is extracted :

Expose some crystallized ferrocyanate of potash to a moderate
heat until water ceases to be separated; put the dried powder into
an iron bottle, furnished with a tube to conduct gas; the bottle is
then to be put into a moderately strong fire, and to remain there
as long as gas is evolved; in this operation the cyanide of iron is
decomposed, but not the cyanide of potassium, this salt remaining
mixed with the oxide of iron and charcoal resulting from the de-
composition of the cyanide of iron; the cyanide of potassium is
to be dissolved out by water, and the solution, after filtration and
evaporation, is to be set aside to crystallize; the salt obtained, after
drying in a gentle heat, being deliquescent, is to be kept in well-
stopped bottles.

If the cyanide of iron should not have been entirely decomposed,
crystals of ferrocyanate of potash will be obtained with the cyanide
of potassium: they are easily distinguishable, and are to be sepa-
rated.

To prepare hydrocyanic acid, of the strength proposed by Vau-
quelin, admitted into the last Dublin Pharmacopeeia, and of about
one-fourth the strength of Magendie’s solution,

Take of tartaric acid.......... sie = sheath ‘seus))) hen CAIUS
cyanide of potassium............ 3
Gistilled water... as 2 aces ca.cc seen /L OUNCE,

First dissolve the tartaric acid in {the water in a small vial; then
add the cyanide of potassium and immediately cork the vial, the
cork for a short time being firmly kept in by the finger ; then agitate
the vial in a vessel of cold water to lowér the heat produced.
When all action has ceased, set the vial aside in a cool and dark
place for twelve hours, in order that the bitartrate of potash may
form and subside; the clear solution is to be poured off and pre-
served for use. ———
VANADIUM—A NEW METAL.

M. Sefstrém, Director of the School of Mines at Fablun, while
examining a kind of iron remarkable for its extreme softness, dis-
covered a substance, the properties of which differ from those of
all previously known bodies, but the proportion was so small that
it would have been tedious and expensive to procure enough for a
detailed examination of its properties. ‘This iron was from the ore
of Taberg in Sméland, which however contained merely traces of
the substance in question, M. Sefstrém finding that the pig-iron

contained

152 Intelligence and Miscellaneous Articles.

contained a much larger quantity than the iron prepared from it,
thought that the scoriz.formed during the conversion of the cast
into wrought iron would be still richer: this conjecture was con-
firmed by experiment ; and M. Sefstrém being enabled thus to pro-
cure a sufficient quantity of the new substance, he examined its
properties, in conjunction with M. Berzelius.

The name of Vanadium, from Vanadis, a Scandinavian divinity, is
provisionally given to the substance. Vanadium forms an oxide
and an acid with oxygen; the acid is red, pulverulent, fusible, and
on solidifying becomes crystalline ; it is slightly soluble in water,
reddens litmus, gives yellow neutral salts and orange bisalts. Its
combinations, with acids or bases, dissolved in water, possess the
singular property of suddenly losing their colour, assuming
if again only at the moment of returning to the solid state; and if
then redissolved they preserve their colour. This phenomenon
appears to have some analogy with the two distinct states of the
phosphoric acid and phosphates.

Hydrogen gas reduces vanadic acid at a white heat; a coherent
mass remains, which has a weak metallic lustre, and conducts elec-
tricity perfectly ; but it is not certain that the reduction is complete.
Vanadium thus obtained does not combine with sulphur, even when
heated to redness in an atmosphere of its vapour. Oxide of vanadium
is brown, almost black; it dissolves readily in acids, The salts are
of a very deep brown colour, but on the addition of a little nitric
acid, effervescence occurs, and the colour becomes of a very fine
blue.

Sulphuretted hydrogen, and even nitrous acid reduce vanadic
acid combined with another acid, to the blue matter, which appears
to be a compound of vanadic acid with the oxide of vanadium,
analogous to the compounds formed by tungsten, molybdena,
iridium and osmium. ‘The oxide and acid of this metal produce
other combinations, which are green, yellow and red, and all soluble
in water. When the oxide of vanadium is produced in the humid
way, it is soluble in water and the alkalies. The presence of a salt
renders it insoluble, and upon this effect may be founded a process
for precipitating it. The vanadates dissolved in water are decom-
posed by sulphuretted hydrogen, and converted into sulpho-salts,
of a fine red colour. Chloride of vanadium is a colourless fluid,
very volatile, and produces a thick red vapour in the air; the flu-
oride is sometimes red, at other times colourless, but always fixed.
Before the blow-pipe vanadium colours fluxes of a fine green, like
chrome.——Ann. de Chim, xlv. p. 332.

It appears that this new metal has also been discovered by M.
del Rio, in a lead ore found in Mexico. —Jézd. xlvi. p. 205.

MAGNESIUM.
A report was made to the Academy of Sciences, on the 21st of
February, on the mode adopted by M. Bussy, for obtaining mag-

nesium in a metallic state, which is by decomposing chloride of -

magnesium by means of potassium. Magnesium is a brilliant metal,
of

OO a a

Lntelligence and Miscellaneous Articles. 153

of a silvery whiteness, perfectly ductile and malleable, fusible at a
comparatively low temperature, and, like zinc, capable of sublima-
tion at a temperature very little higher than that of its fusibility,
and condensing under the form of small globules. It does not de-
compose water at the ordinary temperature; it oxidizes at a high
temperature and is converted into magnesia, slowly when it is in
rather large pieces, but when it is in fine dust it burns with great
splendour, throwing out sparks like iron in oxygen gas.—Royal
Inst. Journal, May 1831.
ON OXALIC ACID. BY M. GAY-LUSSAC.

I was aware with all chemists, that oxalic acid when heated is
partly volatilized, and that the remainder is decomposed, yielding
a mixture of carbonic acid and an inflammable gas*. As I was de-
sirous of knowing more particularly the nature of the inflammable
gas, I put some very pure crystals of this acid into a glass retort,
which was gradually heated. At 208° Fahrenheit, the acid was
completely fused; at 230° an elastic fluid was disengaged with the
vapour of water ; the volume of gas gradually increased as the tem-
perature of the acid rose by the loss of the water of crystallization ;
from 248° to 266° the evolution of gas was extremely rapid, and
it continued until the oxalic acid was completely decomposed, but
with some variations of temperature, which were not precisely
noted.

This ready decomposition of oxalic acid, by a very moderate heat,
is the more remarkable, because unforeseen, and because the
oxalic acid is considered as one of the most stable of the vegetable
acids. Its decomposition by concentrated sulphuric acid, into equal
volumes of carbonic acid and oxide of carbon, is not opposed to
this opinion, and is readily explained by the powerful affinity of
sulphuric acid for water, in consequence of which it destroys and
carbonizes a great number of organic vegetable substances.

The examination of the elastic fluids, obtained by the decompo-
sition of oxalic acid, has shown me that they are very nearly a
mixture of 6 parts of carbonic acid gas, and 5 of oxide of carbon.
These proportions varied but little inthe course of the operation,
yet towards the end the proportion of carbonic acid was rather
larger.

The decomposition of the oxalic acid by a moderate heat made
me suspect the intervention of sulphuric acid. 1 found, in fact,
that in employing this acid the oxalic acid began sensibly to de-
compose at the same temperature as when it was alone; that is to say,
at from 230° to 239° of Fahrenheit. But an essential difference is,
that with sulphuric acid equal volumes of carbonic acid and oxide
of carbon are obtained, as Débereiner has observed, while oxalic
acid alone gives the same gases in the proportions of 6 to 5,

This difference led me to think, that during the decomposition of
oxalic acid, without the presence of sulphuric acid, another com-
pound must be formed to explain the loss sustained of oxide of

* See Phil. Mag. and Annals, N.S. vol. ix. p. 161.—Eprr.
N.S. Vol. 10. No. 56, Aug. 1831. X carbon

154 Intelligence and Miscellaneous Articles.

carbon. An experiment performed with this view showed that the
water given off by the oxalic acid was acid, and that it contained
formic acid, This acid appears at first in but small quantity, be-
cause it is mixed with so much water, but it distills more and more
concentrated, and towards the end of the operation, when the oxalic
acid is dried, it has a very penetrating smell and a sharp taste.
According to the proportions found of 6 volumes of carbonic acid
for 5 volumes of oxide of carbon, and supposing that it is the de-
ficient volume of this gas, which with the assistance of water forms
formic acid, it will appear that for 12 proportions of oxalic acid
there is formed one volume of formic acid.

This theoretical result appeared to me to agree very well with
experiment ; but I did not satisfy myself of it by a direct mode.
The hydrogen was unquestionably supplied to the formic acid by
water, and not by the oxalic acid, for the carbonic acid and oxide
of carbon ought to have been produced in equal volumes; added
to which, it is a necessary consequence of the well-known nature of
oxalic acid, as.shown by the experiments of MM. Dulong and
Dobereiner. I may remark, that if the decomposition is not urged
too strongly, nearly all the oxalic acid is destroyed; no sensible
quantity being volatilized.

The observations which I have now made, appear to me to ren-
der it imperiously necessary no longer to separate oxalic acid from
the other combinations of oxygen and carbon,—carbonic acid and
oxide of carbon; it may be arranged among the acids into which the
radical enters in two proportions, and the name proper for it would
be hypocarbonic acid, analogically with the hyposulphuric, and hy-
posulphurous acids, &c.; but it may perhaps be better to delay this
change of nomenclature.— Ann. de Chim. xlvi. p. 218.

ON GALLIC AND PYROGALLIC ACID. BY M. HENRI BRACONNOT,

According to Berzelius pure gallic acid can be obtained only by
sublimation; that obtained by infusion, he conceives, always con-
tains tannin, while M. Braconnot, on the other hand, considered
that procured by infusion quite pure. To determine the question
Braconnot prepared some by each mode, and the results of his ex-
periments are, that they are distinct acids ; to that prepared by infu-
sion he appropriates the name of gallic acid, while the sublimed acid
he distinguishes by the term of pyrogallic acid.

Some very white gallic acid, which gave no precipitate with ge-
latin, was exposed to a heat insufficient to obtain any sublimate; it
dissolved into a brown liquid which crystallized on cooling; it con-
tained, in fact, much gallic acid, with an additional brown matter
that gave an abundant precipitate with gelatin,

Thirty grammes of gallic acid, previously well dried, were gra-
dually heated in a proper apparatus to obtain the sublimed acid ;
three grammes and a half were procured; it was very white, and yet
the aqueous solution precipitated gelatin. The residue of this
sublimation, redissolved in water, gave a brown liquor, which be-

came

Intelligence and Miscellaneous Articles. 155

came much darker with persulphate of iron, and of a blueish black
colour with the protosulphate of iron; these are characters which,
as we shall presently see, Indicate the presence of pyrogallic acid,
but not that of gallic acid; the same brown liquor was abundantly
precipitated into a glutinous elastic mass by gelatin. It therefore
contained a different kind of tanning from that which exists in the
gall-nut. It may -be inferred from these results, that heat, by acting
on gallic acid, occasions its elements to unite in a new order to give
rise to tanning matter and pyrogallic acid. Bouillon-Lagrange has
already remarked that the sublimed acid possesses characters which
prevent its being confounded with common gallic acid. According
to Berzelius it does not redden litmus paper; Braconnot always
found it todoso. Suspecting that this effect might be derived
from the tanning matter which it retains, that was separated by oxide
of tin; it still however reddened litmus paper, but not so strongly
as gallic acid.

The taste of pyrogallic acid is sharp and bitter; it requires 24
parts of water at 55° Fahrenheit, for solution, whereas gallic acid
requires 100 parts at the same temperature. When sublimed a
second time the greater part is decomposed, leaving a residue of
tanning matter or of charcoal. Like the gallic acid it is soluble in
zther; the aqueous solution is perfectly colourless ; but exposed
to the air it becomes gradually coloured and eventually deposits
a brown matter which has the properties of ulmin, which increases
more and more as the water lost by evaporation is renewed, and in
some days the acid is entirely decomposed.

Ifa solution of persulphate of iron be poured into one of pyrogallic
acid, the latter is instantly decomposed by the oxygen of the per-
oxide of iron, which becomes protoxide. ‘The solution becomes of
a very dark-brown colour, which by spontaneous evaporation yields
aremarkable quantity of colourless transparent crystals, that may
be separated from a brown matter by alcohol; these crystals are
protosulphate of iron. The brown spirituous solution contains no
more iron: evaporated with a gentle heat it leaves a residue,
which re-dissolved in water, yields a very sour astringent solution,
containing free sulphuric acid and a tanning matter which precipi-
tates gelatin abundantly.

The protosulphate of iron gives a blackish blue colour to a solu-
tion of pyrogallic acid. If into an aqueous solution of the same
acid only a very little of the persulphate is put, so as to decompose
only a part of the acid, the protosulphate of iron produced gives
eventually a blue colour to the solution. These reagents act ina
very different manner with gallic acid; for the persalts of iron al-
ways give a fine blue colour with it, while the protosalts occasion
no change.

When nitrate of silver or protonitrate of mercury is added to an
aqueous solution of pyrogallic acid, the whole of the metal is in
stantly precipitated in the metallic state.

A saturated solution of pure gallic acid in water is not rendered
turbid by nitrate of silver; after some time the solution becomes

X 2 brown,

156 Intelligence and Miscellaneous Articles.

brown, and metallic silver is precipitated ; with protonitrate of mer-
cury it gives an orange yellow precipitate, which becomes gra-
dually of a dirty green colour.

When pyrogallic acid is slightly heated with concentrated sul-
phuric acid, it does not impart any particular colour, and is not sen-
sibly decomposed, which is rather a remarkable circumstance.
Purified gallic acid was treated in the same way, with the intention
of discovering a tanning matter: the acid assumed a fine purple
colour, which disappeared on the addition of water, and crystallized
gallic acid was precipitated. if the solution of gallic acid in sul-
phuric acid be exposed to a greater heat, part of the purple colour
yet remains; but almost the whole of the gallic acid is converted
into a powder of a fine brown colour, which has the characters of
ulmin, and without the development of tanning matter.

The compounds of pyrogallic acid with bases were not examined,
except the pyrogallate of alumina, which is easily obtained by dis-
solving freshly precipitated gelatinous alumina in pyrogallic acid.
A very acerb liquor is formed, which is rendered turbid by heat, and
becomes transparent again on cooling, precisely like acetate of
alumina. I: produces an exceedingly abundant white coagulum
with gelatin. The pyrogallate of aiumina is capable of being cry-
stallized. It appears to redden litmus paper even more strongly
than the acid itself, as if the alumina in this case also acted like an
acid. The gallate of alumina also possesses properties similar to
those just described.-

According to the opinion expressed by Berzelius, that which
chemists have imagined to be pure gallic acid contains much
tannin ; endeavours were made to combine the latter with the sub-
limed acid, with the intention of reproducing a substance similar
to gallic acid; but every effort was unsuccessful.

From the observations which have been detailed, M. Braconnot
concludes:

Ist, That gallic acid obtained in the humid way, and properly
purified by animal charcoal, may be considered as pure and un-
mixed ;

2ndly, That when it is exposed to heat it is converted into a
tanning matter and pyrogallic acid ;

3rdly, That on combining the latter with tannin, gallic acid can-
not be reproduced.— Ann. de Chim. xlvi. p. 206.

ANALYSIS OF TENNANTITE.

To the Editors of the Philosophical Magazine and Annals.

If the subjoined analysis of an ore of Tennantite copper from a
recently opened mine is worthy of insertion in the Philosophical
Magazine, it is at your service. I confess, I regret deeply that the
mineralogical knowledge which was formerly attainable from your
magazine has recently fallen off. Why do not Dr. Turner, Mr.
Heuland, Mr.Brooke, and others, step forward to communicate the
knowledge they possess and keep up the zest for so interesting a

science ?

=“

New Patents. 157

science ? Well may collectors complain that the world is dead
to the science—well may dealers complain that they have no
inducement to collect—when the science is suffered to die away
for want of encouragement from those who ought to promote it by
the dissemination of that information which they possess.
I remain, yours, &c.
An Otp CoRRESPONDENT.

Analysis of a specimen of Tennantite from Trevisane Mine in the

parish of Gwennap, in Cornwall. By J. Hemming, Esq. Vice-

President of the London Mechanics’ Institution, and Lecturer at

that Institution, and also at the Russell and London Institutions.

SiCa ah aencierieycreishezelskatals s\slempsienace?
GO PREG) pie<jsusns are rabeide giat ites 48-4
ATSCBIG ALE. §, ic pake at Shlede ees telly 11-5
BEOUIR ALE AEE ee 14-2
Balser hoe Stayer g< bie eis ave Q1°8
99-19

Can any of your Correspondents give any account of the che-
mical tests for the new metal ¢ Vanadium’ ? or the process by which
Mr. Johnstone discovered what he calls the Vanadiate of lead, from
the Lead Hills, and, as he says, Alston Moor,—but more probably
from the neighbourhood of Keswick ?

[ Mr. Brooke seems to have anticipated our correspondent’s com-
plaint, as will appear from the present Number. A notice of Vana-
dium will be found in p, 151.—En1rT.]

LIST OF NEW PATENTS.

To C. M. Hannington, Nelson Square. Surrey, gentleman, for
an improved apparatus for impressing, stamping, or printing, for
certain purposes.—Dated the 22nd of January 1831.—6 months
allowed to enrol specification.

To L. Schwabe, Manchester, manufacturer, for certain processes
and apparatus for preparing, beaming, printing, and weaving yarns
of cotton, linen, silk, woollen, and other fibrous substances, so that
any design, device, or figure, printed on such yarn, may be preserved
when such yarn is woven into cloth or other fabric. — 22nd of
January.—6 months.

To R. Winch, Gunpowder Alley, Shoe Lane, London, printer’s
joiner, for certain improvements in printing machines.—29th of
January.—-6 months.

To J. Bates, Bishopsgate-Street- Within, London, esq., for cer-
tain improvements in refining and clarifying sugar. Communicated
by a foreigner.—3 1st of January.—6 months.

To J. C. Schwieso, Regent-street, London, musical-instrument
maker, for certain improvements on piano-fortes and other stringed
instruments,—2nd of February.—6 months,

LUNAR-

158 — . Meteorological Observations for June 1831.

LUNAR OCCULTATIONS FOR AUGUST.
Occultations of Planets and fixed Stars by the Moon, in August 1831.
Computed for Greenwich, by Tuomas Henperson, Esg. ; and
circulated by the Astronomical Society.

ss Immersions. | Emersions.
Jee)
s
Stars’ 8 ac Angle from Angle from!
1831. Names. 5, wz |Sidereal} Mean | |Sidereal| Mean
se 2 time. |solartime.| 36] 8 | time. |solartime.| 5 ¢
pt Weal se| Eo
< A 4 zm
Fr Ser ee Osi. ek a EL aX) | cg
Aug. 1) f Tauri ...) 5°6 379 23 37| 14 57 1183] 96] O 39] 15 59 | 269
2\71 Tauri ...| 5°6 503 G2 241 13 40} 94] 54}|23 18] 14 34 | 298
6 Tauri...) 5 510 23 29] 14 45 | 1386} 96} O 21) 15 37 | 256
& Tauri ...| 5°6 piled 23 25) 14.41 1115) 75).0 25] 15 41 | 277
80 Tauri...| 6 515 0 26| 15 42 | 17 | 339] ) almost touching Star.—

Occulted to places furthe
North.

81 Tauri ...| 5°€ 517 O 31| 15 48 35|357| 0 50| 16 6 |359| 322

(99) Tauri | 5°6 516 O 87] 15 53 |164/126| 1 11] 16 27 | 230) 192

Aldebaran 1 528 SI'S) 13 3 151/133] 4 6| 19 22 | 241 | 236
3/111 Tauri 6 640 OD OW Sale 25 | 349 | 22 12| 13 24 | 357} 320

115 Tauri | 5°6 651 22 59| 14 11 |147]| 108] 23 37| 14 49 | 237 | 197
8) Mercury aWal see Mee 4 38| 19 30 121] 82] 5 26| 20 17 |215|175
1]|/y Virginis*| 4 } deny 18 3} 8 45 | 42] 81/|Under |horizon,| ...
29148 Tauri...| 6 468 Dens

15 34 |107] 78] 3 17] 16 47 |289| 277

* DoubleStar.

METEOROLOGICAL OBSERVATIONS FOR JUNE 1831.
Gosport :—Numerical Results for the Month.
Barom. Max. 30-241. June 20. Wind S.W.— Min. 29-681. June 11. Wind W.
Range of the mercury 0-560.
Mean barometrical pressure for the month ...... Uibabatsdekee ssa . 30-001
Spaces described by the rising and falling of the mercury............ 3-640
Greatest variation in 24 hours 0:315.—Number of changes 24.
Therm. Max. 74°. June 22. Wind W.—Min. 48°. June6. Wind N.
Range 26°.—Mean temp. of exter. air 61937. For 31 days with © in II 60°68
Max. var. in 24 hours 21°-00.—- Mean temp. of spring-water at 8 A.M. 50-48
De Luc’s Whalebone Hygrometer.
Greatest humidity of the atmosphere, in the evening of the 11th.... 90°
Greatest dryness of the atmosphere, in the afternoon of the 3rd... 40
Range of the index .............-+++- Sooneeeasadboadoades Beene eiten ssc rk one 50:
Mean at 2 P.M. 54°-5.—Mean at 8 A.M. 60°2.— Mean at 8 P.M. 68°
of three observations each day at 8, 2, and 8 o’clock......... 60°9
Evaporation for the month 5:30 inches.
Rain in the pluviameter near the ground 1-555 inch.
Prevailing winds, S.W. and W.
Summary of the Weather.

A clear sky, 3; fine, with various modifications of clouds, 16; an over-

cast sky without rain, 63; rain, 4.—Total 30 days,

Clouds.
Cirrus. Cirrocumulus. Cirrostratus. Stratus. Cumulus. Cumulostr. Nimbus,
22 14 28 0 27 17, 17

Scale of the prevailing Winds,
N. N.E, Roe SE ee mee.) OW. .o ANGE Days.
4 l Gin = Baie eae 8}. 5 30

General

Meteorological Observations yor June 183\, 159

General Observations.—This month has been alternately dry and showery ;
but from the powerful influence of the solar rays in June, the showers of
rain were seasonable, and aided the growth of the crops.

In the morning of the 9th at nine o’clock, a large double halo appeared
round the sun, with two parhelia outside of the exterior halo; the inner
edge of the interior halo was twenty degrees distant from the sun’s centre,
and the inner edge of the exterior halo was 22° 35’, while each of the
parhelia was twenty-six degrees from his centre, and they had white trains
seven or eight degrees long.

In the night of the 12th there was sheet-lightning from ten P.M. till
three A.M., when it was accompanied with thunder and heavy rain; the
lightning, which was vivid and of a blueish colour, had nearly ceased to dis-
charge itself from the clouds when the rain came on.

In the afternoon of the 14th two parhelia appeared at the exterior edge
of a large solar halo, from half-past four P.M. till sunset.

Hay-making began here about the middle of the month: the hay was ricked
in dry order, and was found to be average crops, and more in some places.
The wind having prevailed nearly the whole period from the western side
of the meridian, there has been no arid, but rather a moist air, which, with
much sunshine, has had a beneficial effect on the growth of the wheat,
so much so, that with a fortnight’s fine, dry weather it would be fit for the
sickle. Comparatively speaking the barley and oats are rather backward
in growth, yet, like the wheat, they have a promising and plentiful ap-
pearance.

The mean temperature of the external air this month, is equal to the
mean of June for many years past.

The atmospheric and meteoric phenomena that have come within our
observations this month, are, four parhelia ; one lunar and six solar halos ;
four meteors ; one rainbow ; thunder on one day and lightning on two days;

and five gales of wind, namely, four from the South-west, and one from
the West.

REMARKS.

London.—June 1. Fine. 2. Fine, with a very dry atmosphere. 3, 4. Fine.
5. Fine: rain at night. 6—8. Fine. 9. Fine: slight rain at night.
10. Showers. 11. Fine: rain at night. 12. Cloudy. 13, Showers.
14, Very fine. 15. Fine, with showers. 16.Fine. 17. Showers: fine.
18. Overcast. 19. Rain: fine. . 20—23. Very fine. 24. Cloudy: fine.
25. Cloudy: rain at night. 26,Rain: clear. 27. Fine: heavy showers in
theafternoon. 28. Fine. 29. Wet. 30. Cloudy.

P.S. The barometrical observations could not be taken on the 22nd, the
day of the Fete. The columns are consequently left blank. The thermo-
meters, being in a different place, were registered.—R. T.

Penzance.—June 1.Fair, 2—4.Clear. 5. Fair. 6—8. Clear. 9. Fair:
rain. 10. Fair: showers. 11. Fair: rain. 12. Fair. 13. Fair: rain at
night. 14,15. Fair. 16. Clear: showers. 17. Fair: showers. 18. Fair:
rain. 19—21.Fair. 22,23. Clear. 24.Fair. 25.Fair:rain. 26. Fair.
27. Fair: showers. 28—30. Fair.

Boston.—June 1, 2. Fine. 3. Fine: very heavy dew early a.m. 4.Cloudy.
5. Cloudy: rain p.m. with thunder. 6—8. Cloudy. — 9, 10. Cloudy: rain
p.M. 11.Stormy:rain early a.m. 12. Cloudy: rain early a.m. 13. Cloudy:
shewers a.m. andp.m, 14. Cloudy. 15. Fine: rain with thunder p.m.
16,17.Fine. 18. Cloudy: brisk wind. 19. Cloudy: heavy rain early A.M.
20,21. Fine. 22. Cloudy. 23.Fine. 24, 25. Cloudy: rain early a.m.
26. Rain. 27. Fine, 28. Rain, 29. Cloudy: rain a.m. and P.M.
30. Cloudy.

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THE

PHILOSOPHICAL MAGAZINE

AND

ANNALS OF PHILOSOPHY.

——<—

[NEW SERIES.]

SEPTEMBER 1831.

XXI. OnIsomorphism. By H.J. Brooxe, Esq. F.R.S. L.S.
& G:S*

GOME new and important theoretical doctrines relative to
the chemical composition of minerals have, within a very
few years, been advanced, and very generally adopted, on the
continent. They have also been favourably received by some
persons in this country, apparently on the credit of the pro-
posers, and without much, if any, inquiry into the merits of
the doctrines themselves.

The theory of Isomorphism was first introduced by Mr.
Mitscherlich, and was founded upon the observation of a very
near agreement in the forms of crystals of certain chemical
compounds. ‘Thus sulphate of iron and sulphate of cobalt
crystallize in oblique rhombic prisms, and apparently of the
same measurements; and hence the atoms or molecules of the
oxides of iron and of cobalt are assumed to be zsomorphous, or
to possess the same zdentical forms; and the same apparent
agreement having been found to subsist among the arseniates
and phosphates of lead, the molecules of the arsenic and phos-
phoric acids are also assumed to be isomorphous.

From other observations it appeared, that barytes, strontian,
and oxide of lead ought to be isomorphous; and hence that
the salts of those substances, when produced by the same
acid, ought also to be isomorphous.

But on examining the sulphates and acetates it was disco-
vered that their respective angular measurements were not

* Communicated by the Author.

N.S. Vol. 10. No. 57. Sept. 1831. bf alike,

162 Mr. Brooke on Isomorphism.

alike, and they were ascertained therefore nat to be strictly
isomorphous. The sulphates are right rhombic prisms, and
a corresponding dihedral angle. of each afforded the following
measurements: ;

Sulphate of barytes............ 101° 42’
strontian.......+. 104
lead \...cesasteneeees 103 42

It became necessary therefore that the doctrine of isomor-
phism, in the strict sense of the term, should as a general prin-
ciple be abandoned; and it is not unreasonable to conclude
that the crystals which suggested the theory, and which ap-
pear to measure alike, may really differ in some small quantity
which the goniometer does not detect.

But although the doctrine of isomorphism, or absolute
identity of form, cannot be supported, it has been said that
the forms in each respective case belong to the same system of
crystallization, and they have therefore been termed plesio-
morphous by Mr. Miller, of Cambridge, in a paper on some
artificial crystals, read to the Cambridge Philosophical So-
ciety, in March 1830; and if even the class of primary form
can be indicated with certainty by the chemical composition
of a crystallized body, a benefit will so far have been con-
ferred on science by the theory of Mr. Mitscherlich.

But the doctrine of isomorphism has been carried much
further by Mr. Rose, and other eminent chemists on the con-
tinent, and has given rise to a theory, from which some check
to the progress of mineralogical chemistry is greatly to be
apprehended.

It is well known to mineralogists, that there is a consider-
able diversity in the chemical composition of some minerals
which have been regarded as belonging to the same species.
Among the most remarkable examples are amphibole, pyrox-
ene and garnet.

Before the theory of isomorphism was proposed, it was
conceived that amphibole was composed of some invariable
elements in definite proportions, although, from the disagree-
ment in the analysis of different specimens, neither the nature
nor the proportions of those elements had been accurately
determined.

It was also supposed that the differences in the actual com-
position of different specimens were occasioned by the acci-
dental mixture of extraneous matter with the real constituent
elements of the mineral. This view is taken by Hauy, and
is illustrated in reference to amphibole as follows:

Analysis

Mr. Brooke on Isomorphism. 163

Analysis of a black variety from Cabo de Gato, a green
from Zillerthal, and a white from St. Gothard.

Black. Green. White.
Silex: .:.sivieee 42 vey (SO woe 284
Witney ocak oak WSIS Heo 30°6
Magnesia....0. 10°99 «.. 19°25 «. 18
Alumina..ics.. 7°69 6. | 0°75
Oxide of iron.. 22°69... 11

But the matrix of the black contains a considerable portion
of alumina, that of the green much magnesia, and the white
is found in magnesian carbonate of lime; and hence the dis-
agreeing composition of the three varieties may, he says, so
far be accounted for.

That well-known mineral the Fontainbleau sandstone af-
forded an example of a mixture obvious both to the sight and
the touch. But the form being that of carbonate of lime, it has
been deemed a crystal of that substance mixed with a very
large proportion of siliceous matter; and if the quartz had
been present in very much smaller grains, or even in ele-
mentary particles, there is no reason to conclude that the
mixture might not equally have taken place ; for small quan-
tities of silex frequently occur as foreign matter in minerals,
and are so regarded even by the advocates of isomorphism,
and there does not appear any absolute limit to the propor-
tion that may be so involved.

Haiiy appears, therefore, to have been warranted in ascri-
bing the differences of composition of amphibole, from dif-
ferent localities, to mixtures of foreign matter derived more
or less from the bed or matrix in which the crystals were pro-
duced.

The theory, however, which Rose and others have engrafted
on the doctrine of isomorphism in its strict sense, is, that the
supposed isomorphous elements may become substitutes for, and
replace each other, in any indefinite proportions, without vary-
ing the form of the mineral in which the substitution has taken
place.

But the truth of isomorphism in simple binary compounds
having been disproved, the very foundation of the theory of
isomorphous substitution would appear to be destroyed; and
it will be afterwards seen, that this theory both wants the di-
rect support of facts, and leads to contradictory results.

In the Annals of Philosophy for June 1826, is a classifica-
tion of minerals by Berzelius, founded, as he says, upon the
property of isomorphous bodies to replace one another in indeft-
nite proportions.

¥2 According

164 Mr. Brooke on Jsomorphism.

According to this classification 1 atom of silica may com-
bine in eudyalite with 1 atom of soda or lime or zirconia or
protoxide of iron or protoxide of manganese, without any
change of crystalline form; or it may combine with either of
these alone, or, according to the law of replacement or sub-
stitution, with several of them, or even all together, in any in-
definite proportions. In_fetstein it may combine with 1 atom
of soda or potash. In a particular kind of garnet, with 1 atom
of lime or magnesia or protoxide of iron or protoxide of man-
ganese. In pyrope, with 1 atom of lime or magnesia or prot-
oxide of iron or oxide of chrome. UHence soda, potash, lime,
magnesia, protoxide of iron, protoxide of manganese, zirconia
and oxide of chrome, may mutually replace each other in
their combinations with 1 atom of silex, without affecting the
form of the crystallized compound; and hence according to
the theory ‘they are strictly zsomorphous atoms.

Paranthine is said to consist in part of 2 atoms of silex com-
bined with 1 of soda or lime ; and stilbite appears composed
in part of 3 atoms of silex combined with 1 of soda or lime.
But if soda and lime are isomorphous in reiation to 1 or 2 or
3 atoms of silex, there is not any obvious reason why all
the other elements that are deemed isomorphous in relation to
1 atom should not be equally so in relation to 2 and 3 atoms;
and as it appears that some of these are isomorphous in re-
spect to alumina also, when that substance acts the part of an
acid and replaces the silex, as it may do according to this
theory, it follows that the others must also be so; and hence
there is introduced a play of composition into the chemical
constitution of minerals, which in the happiest manner puts
an end to the chemical distinction of species.

Berzelius has given the chemical constitution of some va-
rieties of amphibole, as follows:

Grammatite...... 1 atom of Zri-silicate of lime,
and 1 bi-silicate of magnesia.

Actinolite......... 1 atom of tri-silicate of lime,
and 1 bi-silicate of magnesia,
or of protoxide of iron.

Hornblende ...... 1 atom of tri-silicate of lime,
and 1 —— _ bi-aluminate of magnesia,
or of protoxide of iron.

But if the doctrine of isomorphous substitution is to be
regarded as a general principle, these can be only particular
cases of a more general] formula; for it is not, I suppose, pre-
tended by the theorists, that atoms which are isomorphous in

respect

Mr. Brooke on Lsomorphism. 165

respect of stilbite and paranthine are not so in relation to
amphibole; and if they are so, then amphibole should consist
Of ..ceseeeeeeeeee 1 atom of fri-silicate of X,

or tri-aluminate of X,

and 1 atomof 67-silicate of X,
or bi-aluminate of X.

X being any or all the eight elements given above, and to
which others might be added, in any imaginable proportions.

M. Beudant, who admits the doctrine of isomorphous sub-
stitution, has in his Mineralogy limited the general formula
expressing the theoretical composition of amphibole within
still narrower limits than those of Berzelius; for he restrains
the composition of actinolite to single atoms of tri-silicate of
lime and bi-silicate of iron, and that of hornblende to tri-alu-
minate of lime and bi-aluminate of iron.

There is not, however, a single analysis of any variety of
amphibole that I have yet seen, and there are nearly twent
published by Leonhard in his Handbuch, and by Bondsdort,
as given in the Annals of Philosophy for October 1822, which
affords the slightest ground for M. Beudant’s imaginary
composition of hornblende. Nor is there a single analysis
that corresponds with exactness to any of the other formulz
of Berzelius or Beudant. The reader may therefore satisfy
himself, by comparing the theoretic formula with the pub-
lished analyses, that the theory of isomorphous substitution
is not in respect of amphibole supported by the observed facts;
the evidence of which ought, on the contrary, in reference to
so fundamental and important a change in the doctrines of
cheinistry, to have been both distinct and conclusive.

It must also be recollected that the chemical formule which
the doctrine of isomorphism has been brought forward to
reconcile and support, are in very many instances, as their
author Berzelius has candidly acknowledged, little more than
theoretical assumptions founded upon the actual results of
analysis; the essential together with the accidental or foreign
matter, being all taken, and parceled out in such proportions
as are required by the atomic theory for producing definite
compounds. But in doing this there is generally some in-
tractable surplus of one or more of the elements, which is left
out and is therefore regarded even by the new theory as in-
trusive matter. ‘The results of analysis may also occasionally,
as Berzelius has remarked, be equally well represented by
two or more different formule, according to the proportions
which may be taken of the actual ingredients, and the manner

in

166 Mr. Brooke on Jsomorphism.

in which these may be distributed in forming binary com-
pounds; and hence what might appear as isomorphous sub-
stitution under one formula, might become foreign matter
under another, which equally well represents the original
analysis.

But even if the varying results of analysis had supported
the new theory, it might fairly have been inquired, whether
the known disagreements in chemical composition could not
be accounted for upon any other probable supposition.

Now the obvious one of accidental mixture, which is so
apparent in the Fontainbleau sandstone, might probably have
rendered any new theory unnecessary,—for the observation
and the statements of Hatiy already given might generally
have furnished an explanation of the disagreements in ques-
tion; yet even if those disagreements could not in all cases
have been explained by reference to the matrix, but that the
mineral should be found to contain matter which is also foreign
to that matrix, such matter might still have been present at
the time the mineral was formed, and hence might have be-
come enveloped in it.

But the supporters of isomorphous substitution will pro-
bably say, that all which might be considered foreign matter,
ought to appear in the mineral in indefinite quantities, and not
in those near approaches to definite proportions which have
given rise to the new theory. This argument is not however
really opposed to the supposition of the disagreements being
occasioned by mixture of foreign matter.

I shall suppose, for the purpose of illustration only, that
amphibole consists essentially of a single atom of tri-silicate
of lime, and that all else which might be discovered by
analysis is accidental mixture. But it may be said, that the
magnesia and iron and manganese which are present in am-
phibole are frequently combined nearly in definite proportions
with the silica, and perhaps as tri-silicates, affording a pre-
sumptive agreement in favour of substitution.

But if we suppose the proportion of silica present when the
mineral was formed to have exceeded that which was neces-
sary to combine with the lime in the production of our sup-
posed amphibole, there does not appear any ground for con-
cluding that the remainder of the silex might not combine in
definite proportions with the other matters that were present,
although foreign to the constitution of amphibole; that the
same circumstances which determined the composition of a
tri-silicate in the amphibole, might not occasion the produc-
tion of éri-silicates of the foreign matter ; and that the pee

anc

Mr. Brooke on Isomorphism. 167

and extraneous silicates thus produced might not be cemented
together and cased up, as it were, by the true amphibole, in
the same manner as the sand in the Fontainbleau mineral:
and if this were the case, the result of analysis would be such
as it now appears, approaching more or less nearly to definite
composition, as the different foreign ingredients happened to
be present in quantities more or less nearly corresponding to
definite proportions.

But the theory of isomorphous substitution appears to
involve the much more general chemical law, that any indefi-
nite number of binary compounds may combine together in all
possible proportions ; that 1 atom of silicate of lime may, not
merely mix, but combine with 100 or 1000 atoms of silicate of
soda, together with as many of silicate of potash, and a dozen
other substances. For the doctrine of substitution implies,
that if 1000 atoms of silex should exist in circumstances fa-
vourable to the production of a compound mineral, and that
in the formation of such mineral there should be required
1000 atoms of lime to be combined with the silex, and only
999 atoms should be present, these would, according to the
existing doctrines of chemistry, combine with 999 parts of the
silex, and the remaining part would combine with a particle
of magnesia or iron, or some other matter supplied from the
other elements surrounding it. But this separate binary atom
must, according to the new theory, become at the same time
chemically associated with the 999 parts of silicate of lime; for
it would otherwise be simply mixed, as any other foreign
matter accidentally present might be, and would not then be
a constituent part of the mineral, as the theory of substitu-
tion requires.

But an inquiry here presents itself, whether, if the differing
atom be only plesiomorphous, it may still act as the substitute
for the atom of lime; and if it may, would the crystal so formed
be isomorphous, or only plesiomorphous.

M. Beudant appears to adopt the theory of zsomorphism, in
its strict sense, in those compounds in which silica and alumina
act the part of acids; but in relation to certain carbonates, he
assumes the theory of plesiomorphism, and ingrafts upon it
a new theory of his own, relative to the dependence of the
angle of the plesiomorphous crystal upon the number of its
substituted or replaced atoms. He says, in page 60 of his
treatise on Mineralogy, that where the carbonates of lime,
iron, or magnesia exist together in a mineral in any propor-
tions, the angle of its primary form is an arithmetical mean
of the angles of the primary forms of its component parts.

Thus

168 Mr. Brooke on Fsomorphism.

Thus if the primary rhomboid of carbonate of lime and mag-
nesia, consisting of 1 atom of each, measure 106° 15’

And if carbonate of lime measure.......seceeeveeere 105° 5!

Carbonate of magnesia Must MEASUTE.....eeeeeereee 107 25

together...... 212 30
the half, or 106° 15’, being the angle of the compound.

Again, if a mineral contain 10 atoms of carbonate of lime,
and 1 of carbonate of magnesia, its angle may, according to
this theory, be found as follows:

10 times 105° 5’, the angle of carb. of lime, is 1050° 50’

once ... 107 25, the assumed angle of car- 107 25

Donate of MBeNEsIa os. cclscoehsons oaemsedearesiars
g ; j , oats
together...... 1158 15
of which 1-11th, or 105° 17’ 43", should be the angle of the
compound mineral.

But this theory is at variance with accurately measured cry-
stals, and has doubtless arisen from some error in M. Beudant’s
experiments which has escaped his notice.

A mineral from Zilierthal named Breiinnerite may be ad-
duced as an instance of disagreement with M. Beudant’s
theory. The mineral was analysed by myself, and afterwards
by Stromeyer, and found to consist of

Carbonate of magnesia 86 or 9 atoms
Carbonate of iron....... 14 or 1 atom

If the angle of carbonate of magnesia be, as before given,
107° 25', that of carbonate of iron being known to be 107°,
the angle of the compound must obviously, according to M.
Beudant’s theory, be Jess than 107° 25', whereas it has been
found by repeated measurements to be 107° 30’.*

But the theory of isomorphous substitution appears also to
be at variance with itself by affording contradictory results.

Thus it is said by Berzelius that paranthine may be com-
posed of bz-silicate of lime and silicate of alumina, or bi-sili~
cate of soda and silicate of alumina. Hence these two com-
pounds are regarded as isomorphous, and may produce
square prisms of paranthine. But sodalite, whose crystals
are regular dodecahedrons, are composed as the soda pa-
ranthine it is said may be; and hence the two paranthine com-
pounds may give dissimilar forms, and the elements lime and
soda are and are not isomorphous.

Again, according to the formula given by Berzelius to ex-
press the composition of ewdyalite, zirconia being isomorphous

nearly.

* See Phil. Mag. and Annals, N.S. vol. i. p. 397.—Enrr. t
with

“=

Mr. Brooke on Isomorphism. 169

with the substances already enumerated, ought therefore to
replace or be replaced by any of them without occasioning
any change in the form of the compound. Therefore eudya-
lite, whose form is a rhomboid, might be composed wholly of
silicate of zirconia, acompound which occurs as a square prism
in zircon; or it might be composed wholly of silicate of iron
or magnesia, which is the composition of olivine, whose cry-
stalline form is a right rhombic prism. Hence the same che-
mical formula, denoiing a silicate of any or all of nine ele-
ments which are assumed to be zsomorphous, represents the
composition of at least three different minerals, whose re-
spective forms are a square prism, a right rhombic prism, and
a rhomboid.

But there are other difficulties in the way of isomorphism,
which do not appear to have been considered, and which arise
out of results that are at variance with the assumption of any
fixed relation between the crystalline form of a mineral and
the forms of its constituent molecules.

The crystalline form of sulphur is either a right or an
oblique rhombic prism, according to the circumstances under
which it crystallizes. Hence, unless some new element not
hitherto discovered enters into the composition of one of these
forms, the crystalline form of even a simple substance de-
pends upon the mode of arrangement of the molecules in the
crystal as well as upon their figure.

The crystalline form of silver, of copper, and of bismuth, is
a cube, and the sulphurets of these metals, (as sulphur must
be regarded as isomorphous in respect of each,) might be ex-
pected to present similar forms. But the sulphuret of silver
is a cube, that of copper a right rhombic prism, and that of
bismuth also a right rhombic prism, but differing in its angle
from the sulphuret of copper.—Arsenic combines with sul-
phur in two different proportions, and producing different
primary forms. Hence the proportion of a common element,
and therefore an isomorphous one, occasions a change, even
in the system of crystallization.

Sulphuret of silver and sulphuret of lead are both cubes,
and hence silver and lead should be isomorphous. But chlo-
ride of silver is a cube, and chloride of lead a rhombic prism.

These remarks are thrown together for the purpose of
calling the attention of those by whom the theory has been
perhaps over-hastily received, to a closer investigation of its
merits; that ifit be really founded on sound principles, its ap-
parent inconsistencies may be explained, and if otherwise, that
it may not remain an impediment to the progress of analytical
research into the true chemical composition of minerals.

N. S. Vol. 10, No. 57. Sept. 1831. Z XXII. Lx-

Rare. |

XXII. Exposition of a New Dynamico-Chemical Principle.
By Mr. Joun James WaTrERstoNE*.

“ The new discoveries, in short, reveal to us the world of secret motions,
whose laws are probably analogous to those of the universe, and which
deserve to be the subject of our most earnest meditations,”

@rsted on Thermo-Electricity, Edin. Encyc.

WHEN we reflect on the progress which has been made,

and is still making, in the physical sciences, and more
especially in those which investigate the active properties of
matter ; when we behold that insatiable thirst after discovery,
that enlightened spirit of inquiry,which so universally pervades
the philosophic world, it becomes a source of exalted gratifi-
cation to trace the steps which have led to so many brilliant
results, and in contemplation of the future to look forward to
that period when all that is now concealed under the veil of
mystery shall finally be exposed in the sublime grandeur and
simplicity which so eminently characterizes the works of na-
ture. ‘The illustrious example which Newton held forth to
posterity, of a philosopher who applied mathematical reason-
ing with so much success in explaining the grander phzno-
mena of the universe, introduced the same system amongst
those who succeeded him; which, joined to experimental ana-
lysis, have unfolded a series of the most splendid discoveries
in every department of natural philosophy. Heat, electricity,
magnetism, and light, are the principal fields in which the
powers of induction have been most conspicuously displayed.
The late discoveries and researches of Young, Ciirsted, See-
beck, &c. have shown that those sciences are intimately con-
nected, and that the actual principles of nature, if we except
perhaps gravitation, interfere with each other in such a man-
ner as to lead us to conjecture they may all be particular
modifications of one agent. If we, however, consider the nu-
merous insulated facts which experimental investigation is so
fertile in producing, that cannot even be generalized under any
special laws, or included under any common analogy, we must
be sensible that a vast distance yet separates us from the pri-
mary causes of all those phenomena.

Experiment, however ably conducted, has as yet shown
nothing in heat, electricity and magnetism, but simply and
exclusively the existence of force, and it seems doubtful if it
will ever lead us directly to the knowledge of the essential
nature of those powers. Heat is an example of a repulsive
energy existing between the constituent atoms of bodies, and all

* Communicated by the Author.
the

Exposition of a New Dynamico-Chemical Principle. 171

the different situations in which it and various substances are
placed in relation to each other, serve only to exhibit instances
in which the quantity and intensity of the repulsive power
varies, thereby enabling experimentalists to deduce general
laws which govern a diversified series of phanomena.—Elec-
tricity and magnetism, on the other hand, present still more
curious instances of invisible forces exercising functions which
rival gravitation in the important parts they sustain in the
ceconomy of nature. Modern discoveries have developed the
intimate nature of their connections; and the display of polar
forces being their most remarkable feature, is so peculiar to
them alone, that we are induced to look upon them as modifi-
cations of the same elementary principle. ‘These powers are
likewise connected with heat and light, which latter are in
most cases coexistent.—Hlectricity is the basis of chemical
affinity, and heat is either absorbed or evolved in chemical
action; the former is in most cases accompanied with a simul-
taneous change in the latter, whilst the latter in peculiar cir-
cumstances induces electrical phanomena.— Magnetism is
weakened or destroyed by an excess of heat; whilst the more

refrangible rays of light possess evident magnetic properties.
Thus are all those subtle agents connected together in the
different effects which they communicate to matter, and in the
variety of forces which harmonize the routine of natural pha-
nomena. Gravitation alone appears to be excluded from this
system of interference; no difference in its intensity, as far as
experiment has yet shown, being consequent upon any change
which may take place either in temperature or in electric state.
Are we then to conclude that heat and electricity are removed
from the sphere of its action? that they act independently of
its general influence? If such is their relation to each other,
our conceptions of relation and quantity are violated, and the
nature of their existence must not only be different but contra-
dictory to every thing of which we can form the remotest con-
ception. Experiment, however, warrants no such conclusion ;
the process appears too delicate, and the magnitude of the
results may, like the parallax of the fixed stars, be placed far
beyond the range of our means of observation, without at the
same time justifying doubts which may be entertained either
of the intimate connection of gravitation and caloric, or of the
real magnitude of these heavenly bodies.—Is it not more con-
sonant to reason to consider them as inseparably combined in
their operations ? We know that both powers surround every
particle of matter, exist in the same space, and generate mo-
tion, at the same time and in the same place: may we not
therefore with justice conclude, that so far from acting inde-
pendently, gravitation may communicate to heat all the pro-
Z2 perties

172 Mr. J. J. Waterstone’s Exposition of

perties by which it is distinguished, and that they may both
be examples of the same elementary force exhibited through
different media?

Such conjectures, although derived from an extensive and
minute survey of the facts elicited by experiment, are yet pre-
vented from ever becoming of practical utility, by our igno-
rance of motion. How does it originate? In what manner are
its effects so complex, and its development so varied? These
are questions which first naturally arise, and indeed compre-
hend al) that can form the object of philosophic inquiry. The
first, relating to its origin, has often been investigated both
by physical and metaphysical authors: many abstract specu-
lations have engaged the attention of the latter, but they uni-
versally partake of the usual defects of that science, referring
every effect to a primary cause, which in whatever way it may
be defined in words, fails to convey any definite conception or
satisfactory meaning to the mind. Disgusted with such idle
and inconclusive reasoning, and despairing of being practically
useful to science by prosecuting such inquiries, it is not sur-
prising that philosophers have never devoted themselves to
investigate this subject on simple physical principles, by the
application of which alone we may expect to further the pro-
gress of natural philosophy.

Two opinions are entertained by philosophers relating to
this subject: the first, that the absolute quantity of motion in
the universe is always the same, suffering neither the smallest
increase or diminution; the second, that ** motion is much
more apt to be lost than got*,” and that therefore “ some other
principle is necessary for conserving it,” to supply the con-
tinued loss incurred ‘by reason of the tenacity of fluids and
attrition of their parts, and the weakness of elasticity in solids.”
The former doctrine was maintained by the Cartesians, who
defended their opinions by the aid of such extravagant hypo-
theses, that Newton and his followers, by showing the obvious
absurdity of their demonstration, adopted the contrary belief,
not so much from the satisfactory proofs brought forward in
support of it, as because it was contradictory to the great
principle of Des Cartes, which was naturally supposed to have
partaken of the general fallacy of his vortical system. Later
philosophers, although ardent admirers of Newton and his
philosophy, have yet rejected his doctrine, and in refutation
of it have brought forward mathematical proofs of its fallacy,
which if not conclusive, are atleast plausible and ingenious.
To prove either hypothesis however, involves reasoning distinct
from the abstract comparison of quantities. An intimate ac-

* 30th Query, Newton’s Optics.
quaintance

a New Dynamico-Chemical Principle. 173

quaintance with nature is requisite. ‘The constituent principle
of the attractive and repulsive powers, and their mode of ope-
ration, may differ from all we can deduce in comparison.
When we therefore perceive matter, once in a state of motion,
gradually arrive at a state of rest, without any visible trans-
ference of its power, having no direct proof to the contrary,
we are induced to consider it absolutely lost. Still the fol-
lowing simple analogy appears to afford evidence of the con-
trary, and authorizes the conclusion, that momentum like
matter cannot by natural means be annihilated, the existence
of both being of equal importance in the ceconomy of nature.
A body when falling towards the earth, gradually accumulates
a quantity of momentum, which is visibly lost when it arrives
at the ground. In this instance the momentum, before it is
transferred to the falling body, is invisible; why may not, there-
fore, the same momentum after collision, be again reduced to
the same invisible state without being actually destroyed ?
The manner in which it appears and disappears is certainly
different, but the latter may be governed by laws as unalter-
ably fixed as those of the former, although from the com-
plexity of the attending circumstances their influence cannot
so readily be appreciated. ‘Thus after collision, in the above
example, undulations or vibratory motions are always ob-
served to take place. These changes are influenced by the
nature of the composing substance, which again is an imme-
diate consequence of the peculiar molecular forces of the ulti-
mate constituent particles. Since we have this reason to sup-
pose that their molecular forces are, like gravitation, subject
to fixed laws, and are every way of like importance and uni-
versality, it becomes highly probable that they are alone the
invisible agents which abstract this momentum of collision,
without any evidence of its existence being afterwards per-
ceived.

These views of the transference of motion are further de-
serving of attention by their accordance with the simplicity
of nature, and by tending to clear science of all those auxi-
liary causes, the introduction of which, though necessary to
explain the contrary hypothesis, has yet proved a serious
obstacle to the progress of true philosophy. If founded on
truth, they induce a lively hope that matter and motion alone
will be found sufficient to explain all the phenomena attend-
ing the grand cycle of nature’s operations, and that that
system of unity and simplicity which the advancement of dis-
covery is always bringing further into view, will at length be
completely unfolded, and all the physical sciences eventually
traced to the varied development of these two principles.

Two

174 Mr. J. J. Waterstone’s Exposition of

Two opinions are at present entertained of the origin and
nature of gravitation. In the first, no intermedia are deemed
necessary to convey its influence; whilst in the second, di-
rect impulsion is considered essential, and a subtle fluid or
zther is supposed to transmit the power from one region of
space to another. ‘This last doctrine has been reckoned by
some unphilosophical, by introducing a clumsy mode of ex-
plaining that, which certain refined metaphysical speculations
on causality do not require to be explained. But although
the cause which is sought may not on these metaphysical prin-
ciples be necessary, yet it will always remain inconceivable
how two bodies in an absolute vacuum will move towards
each other in accordance with the laws of gravitation; and it
is certainly preferable to adopt the contrary opinion, more
especially if we discover a certain arrangement of the fluid
which will explain the development of an attractive and re-
pulsive energy on the most simple and evident mechanical
principles.

In the following three articles it has been attempted to show,
how an attractive force may exist between two particles pro-
portional to the quantity of matter in each, and which is in
every other respect subject to laws similar to those of gravi-
tation. As it is intended at present to introduce and explain
the general principle alone, without entering into mathemati-
cal details, the systematic arrangement which would otherwise
become necessary, will not be so particularly attended to as
briefness in demonstrating what will be sufficient to convey a
distinct notion of the system; reserving for a future oppor-
tunity its mathematical elucidation and further extension in
explaining a diversified series of chemical and electrical phe-
nomena. The following particulars define what is intended
to be understood as properties of matter coexistent with per-
fect solidity, and are the foundation of all the reasoning after-
wards made use of.

Postulates.—Let it be granted that,

1st, Perfect solidity is accompanied with an inseparable
union of parts.

Many may deny this as an unwarrantable assumption; but
although hypothetical, it is but a corollary to the doctrine
which is at present supported by the most enlightened and dis-
tinguished philosophers, who have inferred from the combining
ratios of the simple chemical elements, that matter is divisible
to a certain extent only, after which no force is capable of
effecting any change in the relative situation of its parts ; and
that when a plenum exists within the surface of the ultimate
particle, no disunion of parts can be effected*.

* See Phil. Mag. vol. Ixii. p. 360; Ixiii. p, 372.—Eprt.
2nd, Per-

a New Dynamico-Chemical Principle. 175

2nd, Perfect solidity is accompanied with perfect elasticity.

This proposition, although inserted in the form of a postu-
late from being dependent on the foregoing, is yet capable of
being demonstrated. If after collision two elastic bodies re-
cover their shape with a force equal to that by which they have
been compressed, they will recoil from each other without any
alteration being effected in the sum of their motions. This
will likewise happen, however much we consider the extent of
compression to be enlarged or diminished; perfect elasticity
being always consequent to an equality existing betwixt the
force of the contracting and that of the dilating vibration.
This vibration may be therefore conceived to be infinitely re-
duced; the body will then be perfectly solid, and this finally
becomes the limit of perfect resiliency.

Exposition of a principle by which it is proposed to explain
the manner in which a mutual attraction may exist be-
tween two particles of matter by the direct impulse of an
intermedium.

I. Let there be an infinite number of particles of cylindric
form, the length of each being indefinitely greater than its
breadth; and let them be extended through space at finite
equal distances from each other; and let an indefinite velocity
be then communicated to each, which may cause them to as-
sume a rectilineal motion in different directions. What will be
the after state of the medium so constituted ?

Each rigid line will pursue an undeviating course, until it
meets with another moving in a contrary direction, when a
collision will take place, and by 2nd postulate a perfect re-
flexion, without the sum of their motions being diminished,
although the whole momentum will then be stored up in the
particles in a different manner, a considerable portion being
gradually abstracted to effect a rotatory movement, whilst the
rectilineal velocity becomes greatly diminished. ‘Thus let the
line ab, having at first a motion in the direction c7, impinge
against another df, having likewise a recti-
lineal motion in a contrary direction es.
Let p be the point of concourse: then by

fd 62832 ab? x 6:2832
iaep. * d lQcp
are the spaces which would be afterwards
described by e and c respectively during
one revolution of the line fd, ab; and the
ratio of the rotatory to the rectilineal momentum, will there.
1'5708 ep d 15708 cp
“5a36ap 8° ~sa3607

dynamical formula

fore be if no elastic force is supposed

to

176 Mr. J. J. Waterstone’s Exposition of

to be exerted. Since perfect resiliency however occurs, the
force of impact will be reflected in contrary directions, and the
supplementary momentum will be exerted at p on fd in the
direction pv, and on/fd in the direction pw in both lines; it
will therefore tend to augment the rotatory, and simultaneously
lessen the rectilineal motion. ‘The actual ratio which these
quantities will have to each other, after the condition of the
medium is established, will be influenced by the following cir-
cumstances; Ist, It is equally probable that the point of con-
course p may be anywhere situated in the lines ab, df; the
extreme cases are, when it coincides with their extremities or
centres of gravity: in the former by the above formula the
rotatory motion is 3ths of the whole; in the latter it is 0; the
mean quantity or ;%ths will, therefore, show the ratio of the
whole quantity of rotatory momentum generated in the me-
dium by this cause singly, and ;%ths that of the remainder,
by which the lines continue their rectilineal motions. 2ndly,
The rotatory motion by the diversified concourse of the
particles will be performed simultaneously
in planes perpendicular to each other.
For while a revolves in the plane arb;
another particle may communicate a rota-
tory impulse in any other direction va,
which by a well-known principle in dyna-
mics will cause the line ad to revolve at
the same time in the planes azb, arb,
perpendicular to each other. In this manner the whole quan-
tity of rotatory momentum effected by the first cause will be
nearly doubled, whilst the elastic recoil will tend further to
diminish the rectilineal motion of the particles. Before ascer-
taining exactly this ratio, the principles of chance, require to
be employed in estimating the frequency of peculiar modes
of concurrence, and thus discovering the mean results of the
combined action of the whole medium. It is not intended,
however, to enter upon this investigation at present, as it is
unnecessary to prove the truth of what has been advanced,
that the primitive momentum is separated into two parts, one
of which is employed in sustaining a rectilineal and the other a
rotatory motion.

II. Let a rigid plane be introduced into this medium : What
will be the corresponding change in its relative density? Let
the line a 6, having a rectilineal motion in the direction de,
and a rotatory motion hg, impinge against the plane of which
AB is a section; the whole momentum in the line will imme-
diately after the first collision be separated into Ist, a reflect-

ing impulse in the direction af; and 2ndly, the influence oe
the

a New Dynamico-Chemical Principle. CH7

the remaining force in continuing the motion towards A B,
and bringing the other extremity 4 likewise in contact with
it, thus inducing a contrary rota-
tory motion, which by encoun- *&
tering and balancing the former 3
will concentrate the whole force *,
in the centre of gravity, and thus *,
cause the line to shoot forwards :
from AB in radiating lines wx;
nearly the whole momentum be-
ing now exerted in a rectilineal
direction. Thus the lines after
collision with the plane AB will
convey a newly acquired impulse
radiating from every point of its
surface, and the rectilineal force thus generated will be com-
municated from one part of the medium to another. For we
may suppose the fluid surrounding the plane to be divided
into concentric films, and the primary rectilineal impulse oc-
casioned by the introduction of the plane’ to be communicated
from the first to the second, from the second to the third,
and outwards successively. After the mutual reflection which
takes place between the first and second, the former will
have given away a portion of its rectilineal force, whilst the
supplementary portion is converted into a rotatory motion.
The same interchange will take place between the second and
third films, whilst at every collision an absolute loss of recti-
lineal momentum will be incurred, which will continually re-
place the vibratory reflections of the first film on the rigid
plane. The radiating influence will be thus conveyed through
boundless space, its intensity diminishing in a ratio of the
distance. The balance of forces which before the introduc-
tion of the plane AB had preserved the homo-
geneity of the medium will be now destroyed,
and the density of its relative parts will be pro-
portional to the intensity of the rectilineal ve- »
locity of the component particles. Thus the
difference between the density of the fluid at
any point surrounding the plane, and of the
same before the introduction of the plane, will
decrease in a ratio expressed by some function
of the distance of that point from the centre of
impulsion. This ratio if énearly developed will 4% A
he represented by a curve // originating at a
finite distance ak from the axis ab expressing the density of
the medium at the surface of the plane at a, and gradually
N.S. Vol. 10, No. 57, Sept. 1831. 2A approaching

178 Mr. J. J. Waterstone’s Exposition of

approaching the asymptote m 7, which is parallel to ab; their
mutual distance am being proportional to the density of the
fluid at an infinite distance from a, or to every part of it be-
fore the introduction of the rigid plane.

III. Let a second rigid plane be introduced and placed at
a distance from the first, indefinitely greater than the extent
of its longitudinal dimensions. What are the effects conse-
quent on this arrangement ?

Let A B be the relative position of the two planes, which
let first be considered parallel, and intersected by a common
perpendicular AB. Let « A, 6 B, represent
their indefinite extension. ‘The rareness of
the medium occasioned by the impulsive force
radiating from the plane being proportional «
to the quantity of rectilineal force exerted
amongst the particles in the same space, and
the sums of the intensities of the rectilineal
motion proceeding from both planes being
greater in the interior space ABthaninBC
AD, on the exterior sides, it follows that the H
medium will be denser in the latter than in C
the former, and more particles will thus im-
pinge in the same time on the exterior than on the interior face
of each. The equilibrium which kept the first plane at rest
before the introduction of the second will be therefore de-
stroyed, and a motion communicated to each, which will cause
them mutually to approach with an accelerating velocity;
and this by the decomposition of forces will likewise take
place at whatever angle the particles are inclined to each other.
Thus the effect consequent on this new arrangement will be the
development of a mutual attractive force.

Observations. —'The foregoing principle is founded on a
simple mechanical effect, which may be made the subject of
experiment. ‘Take a small glass cylinder, suspend it by a fine
thread, and communicate to it a spinning motion round that
centre. Bring it now gently in contact with a glass plate; the
instant that collision takes place the cylinder will be thrown
from the plate with considerable violence, whilst its revolving
motion will have almost totally disappeared. ‘This experiment,
which is easily performed, corroborates what is mentioned in
the first part of Article II. and affords a satisfactory proof of
the efficacy of the general principle. As acorollary to Articles
II. and III. we have to observe, that if the finite particles
were rigid planes of uniform thickness, the attractive power at
the same distance would be proportional to the extent of sur-

face; in other words, to the quantity of matter contained in
the

|B

a New Dynamico-Chemical Principle. 179

the particle. Again, since the intensity of all radiating in-
fluences are inversely as the squares of the distance, it is ex-
tremely probable, although not yet demonstrated, that the at-
tractive power generated by the above principle will likewise
follow the same law. When the distance, however, is so small
that the peculiar shape of the particles will modify the effect,
polar forces will be developed, and the planes will gradually
arrange themselves in a parallel direction, while other peculiar
changes relating to chemical phenomena will simultaneously
take place. These modifications of the influence of the me-
dium when the mutual distance of the rigid planes is small,
will be more complex and interesting according to their
number and mode of clustering together. Thus if we were
to suppose every particle to be composed of an indefinite
number of rigid planes arranged in a fixed order, and kept
in their relative places by the balancing influence of an attrac-
tive and repulsive force, an accordance may be discovered with
the theory now generally adopted, that the atomic weights of all
the chemical elements are simple multiples of that of hydro-
gen; and that the particular properties of the particles of every
different substance result from their individual organization.

The introduction of another medium, the particles of which
may be considered as indefinitely larger than those of the first,
and yet indefinitely smaller than the elementary plane, opens
a new and wide field for the display of an unlimited number of
curious phenomena. ‘These, as far as the subject has as yet
been explored, appear to coincide remarkably with the known
properties of heat,whilst other simple combinations are likewise
successful in explaining many other interesting facts in che-
mistry. Before entering, however, into this boundless region
of inquiry, the circumstances which influence the variable ratio
of the attractive force, and other preliminary theories, must be
subjected to a course of mathematical examinations ;—this will
perhaps form the subject of a future communication.

In conclusion it may be observed, that were the size of the
particles indefinitely reduced, whilst their velocity was inde-
finitely augmented, the density of the medium would be simul-
taneously diminished, whilst the quantity of force existing
in a finite portion by remaining constant may be conceived
sufficient to impel bodies with powers of equal intensity to
those which are exhibited in nature; and this more especially
since we may likewise suppose the rigid planes which consti-
tute these bodies to be indefinitely reduced in thickness, whilst
they still present the same superficies: thus by lessening the
quantity of matter acted upon, the intensity of the action will
be proportionably more vivid and efficacious. Thus were

2A2 the

180 _ Mtr. J. Blackwall’s Examination of

the velocity of the particles such as would carry them in void
space from one extremity of the planetary regions to another
in a second of time, the ratio of their magnitude and mean
distance will approach that of the stars which form a nebula;
whilst the mean space described in the medium by a particle
before the direction of its motion is altered by impingeing
against others, may be indefinitely smaller than any conceiv-
able magnitude. However extreme the rapidity of this action
may be considered, it is yet finite, and cannot therefore be
reckoned irrational or contrary to the institutions of nature.
It is the true primitive standard to which all velocities [upon
the hypothesis] may be compared, as from it every other
motion in the universe is derived.

Professor Ciirsted, as far back as 1813, in his work on the
Identity of Electricity and Chemical Affinity, deduced, from
an extended series of experiments and general view of science,
*¢ that all effects are produced by a fundamental power ope-
rating in different forms of action.” It is remarkable that the
principle we have been explaining is in perfect unison with
the sentiments of this eminent philosopher. A medium is
supposed to envelope the universe, every particle of which is
a minute reservoir of power, which is conserved in the recti-
lineal and rotatory motion with which it is endowed. ‘These
motions, by the introduction of the gross particles of different
substances, are alternately transformed into each other; and
thus the primordial power of CHersted’s doctrine by the varied
structure of the particles of matter ‘* operates in different
forms of action,” and is everywhere developed in the diversi-

fied series of natural changes.
St. John’s Hill, Edinburgh, April 14, 183].

XXIII. An Examination of M. Virey’s Observations on Aéro-
nautic Spiders, published in the Bulletin des Sciences Na-
turelles. By Joun Brackwat1, Esq. F.L.S.*

HE Bulletin des Sciences Naturelles for July 1829, p.131—
134, contains a notice, from the pen of M. Virey, of

my memoir on Aéronautic Spiders, printed in the Transac-
tions of the Linnzan Society, vol. xv. part ii.; and it is parti-
cularly deserving of attention, that the author, by an extraor-
dinary misapprehension, originating apparently in an imper-
fect acquaintance with the English language, not only distorts
the facts I have promulgated and perverts the arguments
founded upon them, but even attributes to me opinions the

* Read before the Linnean Society, May 4, 1830; and communicated
by the Author.

very

M. Virey’s Observations on Aéronautic Spiders. 181

very reverse of those advanced in my paper. Of the great
injustice done to me in that article I have every reason to
complain, were I disposed to give way to personal feelings ;
my sole object, however, in animadverting upon it is the pro-
motion of science, being impressed with the belief that the
principal errors into which M. Virey has fallen, if suffered to
remain unnoticed, must tend to retard its progress. That I
should be thus forced into collision with a distinguished fel-
low-labourer in the field of natural history, I sincerely regret.
As it would be tedious to enter into a minute consideration
of the various misconceptions on the part of M. Virey, ad-
verted to above, I shall particularize such only as directly mili-
tate against the theory I have endeavoured to establish re-

lative to the ascent of aéronautic spiders in the atmosphere.
In narrating the fact observed by me in October 1826,—
namely, that the tissues usually denominated gossamer-webs
are formed at the surface of the earth, and are afterwards
raised into the atmosphere by ascending currents occasioned
by the rarefaction of the air contiguous to the ground when
heated by the sun in serene weather,—M. Virey states that I
witnessed the ascent of webs more than a hundred feet long,
(“des trainées de plus de cent pieds de long de ces toiles,”)
and that I investigated the process employed by the spzders
in fabricating “‘ ces subtils calicots,” as he facetiously terms
them, in reference to the manufacturing district where my
researches were made, “ pour s’élever dans atmosphere et
franchir au loin les espaces.” Now, so far from ascribing the
construction of these webs to spiders, in the instance referred
to, I attribute their formation to the adhesion of the slender
filaments of which they are composed on being brought into
contact by the mechanical action of gentle airs. That the
filaments are produced by spiders I am perfectly well aware,
but I have no where asserted that these animals convert them
into the webs termed gossamer; neither have I affirmed that
they employ such webs to effect their aérial excursions, as
M. Virey intimates: on the contrary, the accomplishment of
their purpose is shown by me to depend upon ascending cur-
rents of rarefied air impingeing against the fine lines emitted
from their spinners, which generally remain distinct through-
out their entire length. The occurrence of spiders upon
gossamer-webs I represent to be entirely accidental ; and that
the former are instrumental in promoting the ascent of the
latter I positively deny: yet M. Virey professes to say on my
authority, that the animals aspire “ a les faire envoler, en les
fixant légérement a l’extrémité d’un corps en pointe.” My
account of the height to which I have seen these webs raised
in

182 Mr. J. Blackwall’s Examination of

in the air appears to have been mistaken by Mr. Virey for a
statement of their length. This is the more surprising, as L
have plainly indicated that they rarely exceed a few feet in
longitudinal extent.

I forbear to offer any comments on the inaccuracy and con-
fusion so conspicuous in M. Virey’s survey of my opinions
concerning the insufficiency of winds, evaporation, and elec-
tricity to occasion extensive and simultaneous ascents of gossa-
mer-webs and spiders, and shall dismiss his review of my
memoir with a few strictures upon the following passage,
which clearly proves that not even my most careful exposi-
tions of the inferences I have deduced from exact experiments
have escaped perversion. ‘Ces animaux” (spiders) ‘* peu-
vent s’élever avec leurs tissus, et tantdt retomber selon le
degré de gravité qui domine et les fait alors précipiter sur la
terre. D’ailleurs, certaines particules d’air raréfie ne peuvent-
elles pas se trouver comme renfermées dans le tissu gazeux de
ces araignées et prendre a la maniére des ballons un mouve-
ment ascendant? L’auteur s’attache a développer Vidée de
cette possibilité; il montre que des araignées peuvent expulser
des fils A une certaine distance et les attacher par la matiere
gommo-visqueuse dont ils sont formés, 4 un lieu plus ou
_ moins éloigné.” In experimenting with a view to demonstrate
the fact, that spiders do not raise themselves into the atmo-
sphere by the exercise of any physical power with which they
are endowed, I repeatedly separated from the spinners of in-
dividuals, when they were ascending, the fine lines which con-~
tributed to give them buoyancy. ‘The result was conclusive.
The animals were quickly precipitated to the ground, and the
detached lines rose with increased velocity in consequence of
being acted upon by a diminished gravitating force. How
completely the true nature and object of this investigation
have been misunderstood by M. Virey appears from the first
sentence of the extract just given from his paper, upon which
it would be superfluous to offer any comment. After inquir-
ing, in the next place, whether the upward direction taken by

ossamer-webs may not be ascribed to the rarefied air in-
closed in them, M. Virey adds, that I have endeavoured to
develop this idea; a piece of information which perplexes me
not a little, as I am wholly unconscious of having made any such
attempt. But the most remarkable circumstance remains to be
considered. Itis assumed by M. Virey, in opposition to the fact
which I have uniformly and strenuously maintained,—a fact,
let it be remembered, confirmed by direct experiments care-
fully conducted and accurately detailed,—that I have rendered
it manifest that some spiders are capable of propelling on
ines

M. Virey’s Observations on Aéronautic Spiders. 183

lines to a distance. On what grounds this assumption, so
contrary to the whole tenour of my experience, is founded, I
have yet to learn.

I shall now proceed to examine the observations on the
ascent of spiders communicated by M. Virey to the French
Institute in June 1829, and published in the Bulletin des

- Sciences Naturelles for October in the same year, p. 130-134 ;
availing myself of the opportunity thus afforded, to introduce
several interesting particulars which have recently come to
my knowledge. Having already rendered it sufficiently ap-
parent that M. Virey does not comprehend my views relating
to the ascent of gossamer-webs and spiders, any notice of the
allusion made to them in the present article is unnecessary ;
I pass on therefore to the author’s remarks on the power
which he supposes spiders to possess of darting out their lines
to a distance. ‘ Je m’étois assuré déja,” he writes, * que
jusqu’a la distance de deux pieds environ, une araignée savait
lancer prestement un fil vers un point quelconque, |’y attacher,
et s’enfuir soudain sur cette corde. II faut que dans Je nombre
de leurs filiéres elles aient des tubes éjaculateurs, puisqu’elles
lancent ces fils indépendamment d’autres sur lesquels elles
s’avancent, et qu’elles émettent en méme temps.” This opi-
nion, which has been entertained by so many eminent natura-
lists, may be refuted without difficulty. If spiders be placed
on a twig fixed upright in a glazed earthen vessel with per-
pendicular sides, containing a sufficient quantity of water com-
pletely to encompass its base, they will be found totally inca-
pable of escaping from their place of confinement in a still
atmosphere; but when exposed to a current of air, or when
blown upon with the breath, the case is otherwise, as many
species may then be perceived to emit from their spinners a
little of their viscous secretion, which being carried out in a
line by the agitated air, becomes attached to some object in
the vicinity, and affords them the means of regaining their
liberty.

These facts were first established by me in 1826, in the
manner here described ; and in the summers of 1828 and 1829
I repeated the experiment with about thirty distinct species of
spiders under every variety of circumstances which appeared
likely to influence the result. My former conclusions, how-
ever, were most unequivocally confirmed, and I am confident
in asserting that these animals have not the power of darting
their lines even through the space of half an inch.

It is certain that spiders can open and close the orifices of
their spinners at pleasure, and can allow their liquid gum to

escape

184 Mr. J. Blackwall’s Examination of

escape so as to form one line or more of greater or less tenuity
and strength, as may suit their convenience. When suspended
by a vertical thread, for example, they frequently suffer another
thread to be carried out horizontally, if blown upon in that
direction; but that they have tubes so organized as to enable
them forcibly to project their lines to a distance, as M. Virey
conjectures, is quite inadmissible.

The curious fact, that all spiders possessing an apparatus
for spinning are not endowed with the instinct to let out their
lines when placed on a twig insulated by water and exposed
to a current of air, I have proved by numerous experiments:
and as this is the case with some of the more common species,
as Aranea domestica and Clubiona atrozx, I take this oppor-
tunity of calling the attention of investigators to the circum-
stance, which if unnoticed might occasion them some dis-
appointment*.

M. Virey, who has experimented with various species of
spiders, and especially with the young of Lpeira diadema, in-
forms us that “ on doit faire ces observations dans une cham-
bre close, ou lair trés calme ne puisse recevoir aucune agita-
tion.” Being unable to detect the presence of any lines which
he considered could contribute to the ascent of these animals,
he concludes that the phenomenon must take place without
their concurrence. ‘ Réfléchissant,” he remarks, ‘‘ aux moyens
par lesquels ces insectes gravissent dans l’air, une seule chose
m’a paru la plus vraisemblable, c’est qu’a l’aide des huit pattes
que l’animal peut faire vibrer avec agilité, 71 nage dans Pair.
On concoit que ces membres rapprochés, ramant quatre a
quatre simultanément de chaque coté, frappent l’air comme des
ailes, et peuvent fort bien enlever cet insecte d’ailleurs si léger.
Ce procédé parait le seul possible dans ce cas. D/ailleurs
Pextréme rapidité, ou ]’agilité incroyable de ces pattes en tré-
pidation, comme la vibration des ailes chez les oiseaux ou les
insectes diptéres qui planent dans lair, font qu’on ne peut
pas toujours bien distinguer leur mouvement.” And again, * Il
est donc plus probable que ces petites araignées volent avec
leurs pattes, que de supposer des effets électriques, ou l’agita-
tion de l’air, ce que nous avons démontré faux par l’observa-
tion directe.” In this bold but fanciful conjecture M. Virey
has been anticipated by Dr. Lister, who, in treating upon his

* It would appear, however, from a notice respecting the habits of
Aranea domestica published in the Zoological Journal, vol. i. p. 283, that,
under certain circumstances, the instinct in question is manifested by that
species of Spider.—Enir.

** araneus

M. Virey’s Observations on Aéronautic Spiders. 185

*araneus subfuscus, minutissimis oculis é viola purpurascen-
tibus, tardipes, et gressu et figura cancro marino non adeé dis-
similis,” observes, “* Certé egregius funambulus est, et miri-
ficé filorum ejaculatione delectatur : neque solim in aére, uti
superiores, vehitur ; sed ipse etiam ascensum velificationémque
molitur, pedibus sc. arctils ad se invicem applicitis sese quo-
dammodo librat, cursum promovet regitque nihilo secits quam
si illi essent 4 natura concessze alee vel remorum ordines*.”
The extreme liability of air to be put in motion, and the ex-
ceeding levity of the lines of very small spiders, are facts which
M. Virey, in the prosecution of his researches, has not at-
tended to with sufficient minuteness. This is evinced by his
supposing that in a close room the air could not be agitated
to such a degree as to affect the results of his experiments.
Have then, I would inquire, the temperature of the body, the
motion of the limbs, and the act of respiration been altogether
overlooked as causes of disturbance? It would appear that
they have; no allusion whatever being made to them, in this
respect, by M. Virey, who even recommends that the hand be
passed before young spiders, when afloat, in order to deter-
mine whether they are supported by a line or not; a proceed-
ing calculated to mislead the inquirer, if executed with haste,
as it generally must be, by disturbing the air and occasioning
a deflection of the line, which consequently might escape his
observation.

These difficulties are entirely avoided by my mode of ex-
perimenting. ‘The vessels containing the twigs on which the
spiders are placed being generally locked up in a book-case,
or put under bell-glasses, the tranquillity of the atmosphere
immediately surrounding the prisoners is ensured without de-
triment to their physical powers. If then they are endowed
with the capability of flying, what is to prevent them from ex-
ercising it when thus stimulated to exertion? Every facility is
afforded them which they can enjoy when at liberty, except
that of air in motion; yet they are never found to escape from
the twigs by flight, notwithstanding their best endeavours to
quit them are persisted in pertinaciously. I have tried this
experiment with several hundred spiders of nearly thirty dis-
tinct species, including the Epeira Diadema in various stages
of growth, and uniformly with the same success. In a calm
atmosphere they are quite incapable of regaining their liberty,
but if placed in a current of air, many species let out their
lines with the utmost facility, along a ed when attached to
any object, they pass in security.

* De Araneis, p. 85.

N.S. Vol. 10. No. 57. Sept. 1831. 2B To

186 Mr. Blackwall’s Observations on Aéronautic Spiders.

To obviate such objections as might be urged against the
use of glass or glazed earthen vessels by the advocates of the
electrical hypothesis of the ascent of spiders, I have in many
instances employed polished vessels of silver, tin, iron, &c.
without producing the least difference in the results. I am
not ignorant that these results have been represented as abso-
lutely subversive of my views. Spiders, it is argued, are com-
pelled to dart out their threads by the electrical excitation
occasioned by currents of air, the phenomenon being con-
sidered inexplicable on any other principle whatever ; but it is
not found expedient to assign a reason for this sudden con-
version of the power ascribed to these animals of propelling
their tines to a distance, into a merely involuntary action en-
tirely dependent upon air in motion. The fallacy of the fore-
going supposition may be proved by placing spiders of the
same species on copper rods insulated by water, and subject-
ing them to the influence of a stream of air so slight as scarcely
to be perceptible. Under such circumstances, any electricity
induced in the spiders by the feeble current must be carried
away as speedily as it is excited, by so excellent a conductor
as copper; nevertheless, the animals can emit or retain their
liquid gum at pleasure, as lines may frequently be seen stream-
ing from the papillae of some individuals; while others, on the
same rod, do not let out any, and may be instantly diverted
from their purpose, should they make the attempt, by the
most trifling causes of disturbance. It is manifest, therefore,
that spiders do not fly, in the strict sense of the word; and
that they are not raised into the atmosphere by the agency
of electricity is equally evident; in short, not a doubt can be
entertained by those whose minds are open to conviction, that
their ascents are effected by means of upward currents of air
impingeing against the lines which proceed from their papillee.

The two species of aéronautic spiders, whose proceedings
are detailed in the Linnean Society’s Transactions, vol. xv.
part ii., I have ascertained to be Thomisus cristatus and Lycosa
saccata, both of which are distinctly mentioned as aéronautic
spiders by Dr. Lister*. ‘The first I have described as having
two pair of eyes situated in the anterior part of the head and
arranged thus, *,.* ; the second as having three pair in front
whose arrangement is thus represented by dots 22. ‘The
species noticed in my paper as remarkable for the skill it dis-
played in spinning its way up the sides of a phial in which it was
confined, and for having existed seventy-five days without
food or moisture, was T. cristatus; L. saccata being neither so

* De Araneis, p. 79, 80, 85.
expert

Mr. Brooke on Mengite, and other Minerals. 187

expert in climbing, nor so tenacious of life under similar cir-
cumstances. I may remark, that in experiments instituted to
decide how long spiders can live without food, the influence
of season should not be disregarded. In winter, unless a high
temperature be maintained by artificial means, the vital func-
tions are performed with much less energy than they are in
summer: of course the natural demand for sustenance, if it do
not cease altogether, is greatly diminished in the former period,
and the animals suffer little comparatively from abstinence.

Another spider of a diminutive size, frequently observed to
take aérial excursions, is the Drassus ater of Latreille, which
appears to be identical with the Aranea obtectrix of Bechstein.

Aéronautic spiders, properly so called, or those species
which znstinctively employ their lines to sail in the atmosphere,
will probably be found almost exclusively among such as are
active during the day and decidedly erratic. Numerous facts
tend to corroborate this idea, the correctness or inaccuracy
of which can only be determined by more extended observa-
tions.

XXIV. On Mengite, a new Species of Mineral; on the Cha-
racters of Aeschenite; on Sarcolite, as distinct from Anal-
cime and Gmelinite; with other Mineralogical Notices. By

H. J. Brooxe, Esq. F.R.S. LS. § G.S.

Ilmenite.

A MINERAL under this name is said to have been de-
scribed in 1821 in Kastner’s Archiv., &c. No. 1. by Prof.
Kupffer of Kasan. It was discovered by Mr. Mengé, near
Lake Ilmen in Siberia, accompanied occasionally by a tita-
nious iron-ore in modified rhomboids, of which a description
and figure, but without measurements, were given by Mr. Levy
in the Phil. Mag. and Annals, N.S. vol. i. p. 26.

Probably from having seen only the iron-ore, Prof. Rose
of Berlin has stated that this was the ilmenite of Kupffer.
The ilmenite is, however, a distinct substance, having for its
primary form a right rhombic prism of 136° 30', the terminal
edge being to the lateral edge very nearly as 17 to 11. The
colour is a more intense black than the rhomboids of titanious
iron, and the surfaces of some of the crystals are perfect and
brilliant. I have not observed any cleavage; the fracture is
uneven to conchoidal with a vitreous lustre. Spec. grav. 5°43.
Scratches glass slightly. ‘The matrix is cleavelandite.

The crystals I have examined are generally small, length-.

2B2 ened

188 Mr. Brooke on Titanious Iron and Aeschenite.

ened in the direction of the axis of the prism, and modified
as in the accompanying figure.

PEUMeSeerecctarvscccerss yo ity Ee
ee ae
Symbols: ....s000s60000)-10,)G, -G.
M,M'= 136° 20!
M,e = 133 10
Mil e= asians
MF n=l dhsp
he = 104 44
ee = 150 32
ee’ = 101 10

Titanious Iron.

The spec. grav. of the titanious iron is 4°74, Hardness
much less than oligiste iron. The measurements of Mr. Levy’s
figure are Olig. Iron. Axot. Iron.

Dk awe = dae
Pp, below 85 36 86° 10' = 85° 5g!

I give the axotomous iron on the authority of Mr. Haid-
inger’s Mineralogy.

Mr. Levy’s e3 does not occur on the crystals I have seen ;
but I find the planes of an obtuse rhomboid, produced by
tangent planes on the terminal primary edges, and calling
these 51, they give the following measurements:

al,bl = 141° 96!
b1,0/1 = 114 38

Aeschenite.

This mineral, which was also discovered and brought from
Siberia by Mr. Mengé, and at first considered by him as
gadolinite, has been analysed by Hartwell, and named by
Berzelius; but as far as I can discover, not otherwise described
than by a very imperfect notice given by Mr. Levy in the first
volume of the present series of the Phil. Mag. p. 27. Some de-
tached crystals I have lately obtained have enabled me to give
the annexed figure and measurements, as taken from rough
planes by the common goniometer.

M,M! = 127°
M.A = 116 30!
M,e = 169 18
Ac = 143

1 1
Assuming the symbol of the plane e¢ to be B, cis E, and a
terminal

Mr. Brooke on Mengite and Sarcolite. 189

terminal edge of the prism is to a lateral edge nearly as 16
to 19. Its spec. grav. is 5°14. Hardness, between that of
apatite and felspar. The colour of the fragments is brownish
yellow, that of gadolinite being green.

Mengite.

The mineral I am about to describe I have named after
Mr. Mengé, who discovered it with the preceding ones near
Miask, and whose mineralogical labours have probably not
been exceeded by those of any of his contemporaries.

The Mengite occurs in imbedded crystals in masses of fel-
spar and mica in a granitic rock. Its primary form is an
oblique rhombic prism, whose terminal and lateral edges are
to each other nearly in the ratio of 13 to 18. The planes are
too dull for the reflective goniometer, and those of the larger
crystals not sufficiently flat to afford very accurate measure-
ment by the common goniometer.

The crystals of this substance present the accompanying
figure, the measurements being nearly as follow:

P,M = 100°
M,M'= 95 30!
P,za = 140.30
Mcyt=, 135
Pye = 187-80

The laws of the planes..........

1
re BSAMME 10 DELiiicscccsscctecdescess™ OSA, SE, iG;

The colour of the crystals is reddish brown. Hardness,
between that of apatite and felspar. Spec. grav. 4°88. No
regular cleavage. Fracture uneven, and the fractured sur-
face dull. It has not been analysed, but from its specific
gravity it is probably metallic. It is frequently attached to
and penetrated by crystals of Aeschenite, and sometimes of
zircon.

Sarcolite from Vesuvius.

This mineral appears to have been first observed by Dr,
Thomson, who, as Haiiy states, sent some fragments of crystals
to him for examination, from which he inferred that the cube
was its primary form, and conjectured that the mineral might
be a variety of analcime. Hence red analcime has been called
sarcolite, and the same name has also been given to red

melinite. A specimen, with which I have been favoured by
Mr. Heuland, and a fragment of a crystal which I have re-
. ceived

190 Mr. Brooke on Sarcolite and Wollastonite.

ceived from Dr. Donati, have enabled me to give the annexed
figure and measurements of this substance; the primary form
of which is a square prism, whose terminal and lateral edges
are in the ratio of 62 to 55 very nearly.

Mher planes: ....c..0.. aie, b1,. b2nc. due
3
are produced by the laws A, sd oY. oAr B, G, G.

P,al = 157°19!
Pa2; =. 128 33
P.d:,.= >, 90

bee tye 198 25
M,é1 = 153 20
M,a2 = 123 34
M,o2 = 102 28
M,e = 153 26
M,d = 135

The plane 52, as the symbol denotes, and as appears in
the figure, occurs singly on each angle, instead of being ac-
companied by a corresponding plane on the other side of c.

Wollastonite from Vesuvius.

This is the same mineral as was, according to the ticket
accompanying specimens from Vesuvius, formerly named
Surlonite or Zurlite. 'The crystals are generally very imperfect,
and the surfaces very dull; a specimen, however, in the pos-
session of Dr. Somerville presented some bright and well-
defined crystals, an examination of some of which has en-
abled me to give the annexed figure and measurements. The
primary form is an oblique rhombic prism. There is one
cleavage parallel to P, and three others parallel to the three
planes a3, h, c2; that parallel to #4 is the brightest, and I
have supposed it parallel to the edge of the prism, and have
thus assumed a different cleavage angle from that usually
assigned to tabular spar. I have, however, found acleavage
corresponding to the plane /, in specimens from the Bannat,
in which the cleavages usually observed and hitherto quoted
are those parallel to P andc2. The ratio of the terminal
and lateral edges of the prism which I have taken as the
primary is very nearly as 25 to 40, and the obtuse angle of
the terminal plane is 91°°56!. The planes are more than
usually perfect, several of the measured angles having agreed
exactly with those given by calculation.

Planes

Mr. Daniell on a new Register- Pyrometer. 191

Planes al, a2, a3, cl, c2, el, €2, €3, FYS- $23 Bile
5 3 1 3 2 1 |

3 1 1
Symbols O, O, O, A, A, E, E, E, D, b, B, H.

P,al = 159°30!
P,a2 = 150 23
P,a3 = 129 42
PA = 110 12
P,f1 = 132 55
P,,f2 = 120 42
P,M = 104 48
P.g' = 1 86 8
Pyebi =) 146007
Poe@! c= 133 33
Pje3 = 115 33
Pg = 93 52
M,M'= 95 38

Some of the crystals are hemitrope, the plane of revolution
being parallel to the terminal plane.

XXV. On a new Register-Pyrometer, for Measuring the
Expansions of Solids, and determining the higher Degrees
of Temperature upon the common Thermometric Scale. By
J. Freperic Danie.t, Esq. F.R.S.*

[With a Plate. ]

i the year 1821 I published in the Journal of the Royal
Institution} an account of a new pyrometer, and the re-
sults of some experiments with it, which were the means of
correcting the highly erroneous notions which had, up to that
time, been generally entertained of the degrees of temperature
beyond the boiling point of mercury. The instrument was
capable of affording correct determinations, connected in an
unexceptionable manner with the scale of the mercurial ther-
mometer; but, although applicable to scientific investigation
in careful hands, it could be inserted only into experimental
furnaces of a particular construction, which greatly limited
its use. The great desideratum still remained of a pyrometer,
which might universally be applied to the higher degrees of
heat, as the thermometer has long been to the lower; and
which, in addition to its use in delicate researches, might eflect
for the potter, the smelter, the enameler and others, in the

* From the Philosophical Transactions for 1830: Part II, and revised

by the Author. + Vol. xi. p. 309.
routine

192 Mr. Daniell on a new Register-Pyrometer,

routine of their business, what the latter daily performs for
the brewer, the distiller, the sugar-refiner, and the chemist.

I shall now have the honour of laying before the Royal
Society a description of a contrivance which, I trust, will be
found to answer all the desired purposes; and which, while
simple enough to be intrusted to the hands of common work-
men in every variety of fire-place, I hope to prove, by the
results of my experiments, to be sufficiently delicate to extend
considerably our knowledge of the expansion of metals, upon
which so much labour has been bestowed by some of the first
philosophers.

I was not aware, at the time when I wrote the account above
referred to, that the subject had been previously investigated
by M. Guyton de Morveau, and that he had proposed to
apply the expansion of platinum as a measure of high tempe-
rature, and more particularly to the purpose of connecting the
indications of Wedgwood’s pyrometer with the mercurial
scale and verifying its regularity. I have since carefully
studied his laborious papers in the Annales de Chimie*, and
the Mémoires de 0 Institut+, which appear to have been but
very little known in this country; and previously to entering
upon the more particular object of the present paper, I must
claim indulgence for a few remarks upon the general state of
the inquiry at the time when its pursuit was abandoned by
that able philosopher.

M. Guyton’s pyrometer consisted of a small bar or plate of
platinum 45 millimetres (1.77 inch) long, 5 millimetres (about
0.2 inch) broad, and 2 millimetres (about 0.08 inch) thick,
placed in a groove formed ina piece of highly baked porcelain.
One extremity of this bar rested upon the solid end, which
terminated the groove, and the other pressed upon the short
arm of a bent lever, the longer arm of which terminated in a
point and moved on a pivot over the graduated arc of a circle ;
indicating by its motion any lengthening of the bar by increase
of temperature. The short arm of the lever was 2.5 milli-
metres and the long arm 50 millimetres in length, and the
latter carried a nonius by which the tenths of a degree might
be read off. The whole was constructed of platinum ; and a
plate of the same metal was made to press, in the manner of a
spring, upon the extremity of the index, to prevent any dis-
placement when withdrawing it from the fire. The description
of this instrument in the first Essay, published in the year
1803, was not accompanied by any explanatory figure; and
the notice in the Annales terminates by announcing that the

* Tome xlvi. p. 276.
+ 1808, Second Semestre, tome ix.—181]1, ibid. tome xii.
inventor

for Measuring the Expansions of Solids, $c. 193

inventor had at that time only begun “a series of experiments
to determine its march, to compare it with the pyrometer
pieces of Wedgwood, and to ascertain the degree of confidence
which might be placed in the indications of the latter.” The
second Essay did not appear till the year 1808, and in it M.
Guyton observes that ‘“‘many persons had expressed a wish
to be made acquainted with the improvements which he had
made in the instrument since its first construction; and that
he had determined in consequence to give a fresh description
of it accompanied by drawings, which might enable artists
who undertook its construction to render it comparable. He,
however, thought it right to give a previous account of the
labours of others in this branch of science, and to remove
certain errors which had prevailed up to that time concerning
the pyrometer then most in use (Wedgwood’s), and which
might possibly prove most commodious, and consequently
most useful, if once the degree of exactitude could be deter-
mined of which it was susceptible.’ The remainder of the
paper is taken up with an account of the most accurate expe-
riments upon the expansion of the metals from the time of
Newton.

The third and last Essay was delayed till the year 1811;
and in it no further description of the platinum pyrometer is
to be found; but a laborious comparison,

Ist, of the indications of the platinum pyrometer with those
of the mercurial themometer ;

2nd, of the same pyrometer with that of Wedgwood; and

3rd, of the degrees determined by these instruments with
those previously known of the expansion, ebullition and fusion
of various substances; in a range of temperature comprising
the highest degrees of the thermometric scale and the lowest
of Wedgwood’s.

Now it is very remarkable that all M. Guyton’s efforts in
this paper are directed to the valuation of the degrees deter-
mined by Mr. Wedgwood’s clay pieces; but that he carries
the comparison of the platinum pyrometer by actual experi-
ment no higher than the melting point of antimony. He
clearly establishes a great error in Mr. Wedgwood’s original
estimation of his degrees to that point ; and, by calculation
upon this basis, continues the correction to the melting point
of iron, “en admettant toujours une progression uniforme
jusque dans les plus hautes températures.” The experimental
comparison was obviously stopped by some practical difficulty
at higher temperatures; and it is easy to perceive in what this
must have consisted. Platinum at a red heat becomes very
soft and ductile; and the lever against which the pyrometric

N.S. Vol. 10. No. 57. Sept. 1831. ZC bar

194 Mr. Daniell on a New Register-Pyrometer,

bar pressed, being of such very slender dimensions, would
obviously be liable to bend, and thus frustrate the experiment:
in addition to which, I can speak from my own experience,
the platinum spring plate and the centre pin would be liable
to a change of texture, which would impede the motion of the
lever, and it would finally become welded to the index; for a
very moderate pressure at a high temperature would produce
this effect.

The conclusion, indeed, of these Essays seems to admit that
the author did not expect that the platinum pyrometer could
ever come into general use: ‘enfin, ces corrections ne peuvent
manquer d’ajouter a l’utilité du pyromeétre d’argile, soit dans
les travaux chimiques, soit dans les arts; quand méme le
pyrometre de platine, plus exact mais moins usuel, serait ré-
servé pour en assurer la marche, et pour servir 4 des recher-
ches plus importantes.”

M. Guyton, however, although he abundantly proves the
incorrectness of Mr. Wedgwood’s estimate of the higher
degrees of temperature, is very far indeed from establishing
the point at which he so earnestly laboured, namely, the re-
gularity of the contraction of the clay pieces; or from substi-
tuting a more correct value of the degrees throughout the
whole range of the gauge than the one which he so completely
overturned. His comparative experiments with the platinum
pyrometer, at the boiling points of mercury and linseed oil,
and the melting point of antimony, led him to reduce the
equivalent of each degree from 130° Fahr. to 62°°5. The
zero point of the clay pyrometer was thus carried back to 517°
instead of 1077°; but it seems to have escaped his notice that
this zero point was declared to be a red heat visible in the day-
light,—a description which cannot be mistaken, and which
clearly could not be below the temperature of boiling oil,
melting lead, or boiling mercury; all of which are, however,
placed above it in M. Guyton’s table. M. Guyton also places
the melting point of silver at the 22nd degree of Mr. Wedg-
wood’s scale instead of the 28th, which was, according to his
own determination, a correction first suggested by Sir James
Hall in the 9th volume of Nicholson’s Journal. Taking the
value of each degree at 62°°5 Fahr., it fixes this point at 1892°
Fahr., which agrees very nearly with my own experiment in
the paper before alluded to; but continuing the calculation
up to the melting point of iron, upon the supposition of an
uniform progression, the 130th degree corresponds with 8696°
Fahr., which, although only about half the amount 17977°
assigned by Mr. Wedgwood, is very far removed from the
result of my calculation 3479°.

Never-

for Measuring the Expansions of Solids, &c. 195

Nevertheless, it is a curious fact, that M. Guyton’s Essay
contains proof that his determination is erroneous, and that
mine is a near approximation to the truth. As a collateral
means of verifying the indications of instruments intended to
measure high degrees of temperature, he refers to the calori-
meter as capable of affording the necessary data by a calcula-
tion from the amount of heat communicated to known quan-
tities of ice or water by bodies in a state of incandescence;
and he quotes the very exact experiments of MM. Clement
and Desormes, who had in this manner determined the fol-

lowing points :

By the Liquefac- By the Heat com-
tion of Ice. pe Water.
ahr.

Fahr. :
Temperature of soft iron melted ... 3988° ...... 3902°
Cast iron just on the point of melting 3164 ...... —-
ME SPORE cane nadudiansndacadenenvauakn DLAs eee
NE NAN EL ak ceacinn pices BAR a peeall she
Tron just ceasing to be Spe veceee 1979
EW ST CPE TRS ee
IES ia dem axneraaze ran ninnans 5 Srty esis 4 OO

My own determinations of the melting point of cast iron,
3479°, of that of copper, 2548°, and of a red heat, about 1000°,
agree very closely and satisfactorily with these results, with
which I was unacquainted at the time of my experiments.
M. Guyton’s remark upon the latter is: ‘II suffit de jeter un
coup-d’ceil sur les résultats, "pour recueillir de nouvelles preuves
univoques de la nécessité de réduire les valeurs données par
Wedgwood aux degrés de son pyrométre. Mais je ne crains
pas de dire que ces réductions sont ici portées trop loin, ainsi
qu’on peut en juger en les rapprochant de celles auxquelles
jai été conduit par l’ensemble des expériences rapportées dans
cet essai. Ce n’est pas que je veuille répandre des doutes sur
exactitude des observations dont je dois la communication
aux deux habiles chimistes ci-dessus cités; mais il est aisé de
faire voir que la différence des résultats est due, pour la plus
grande partie, a la différence des procédés; de sorte que les
évaluations quils ont données aux degrés de l’échelle de
Wedgwood, peuvent, en derniére analyse, et en prenant les
termes moyens dans la latitude que comportent des opérations
aussi délicates, servit plutét 4 confirmer qu’a détruire le sys-
teme de correction que j’ai établi.”

It is worthy of observation, that had the degrees of Wedg-
wood’s pyrometer been valued from this determination of the
fusing point of iron, the result would have better corresponded
with the whole series of phanomena. Instead of 130° Fahr.
as fixed by the inventor, or 62°*5 as corrected by M. Guyton,

2C2 they

196 Mr. Daniell on a New Register- Pyrometer,

they would have been estimated at about 20° Fahr.; and taking
Mr. Wedgwood’s original determination of the fusing point
of silver at 28° of his scale and the zero point at 1077°, the
former would come out about 1650°. By raising the zero
point a little, (and it is much more probable that the tempe-
rature of a red heat fully visible in the day-light is above 1077°
than below it,) we arrive at something like an approximation
to the truth. These wide discrepancies, and the practical
disuse of both Mr. Wedgwood’s and M. Guyton’s pyrometers
for a long time past, prove the expediency of further investi-
gating a subject of so much interest and importance.

The pyrometer, which I shall now proceed to submit to the
judgement of the Society, consists of two distinct parts, which
I shall designate as the Register and the Scale.

The first is a solid bar of black-lead earthenware, eight
inches long, seven-tenths of an inch wide, and of the same
thickness, cut out of a common black-lead crucible. In this
a hole is drilled three-tenths of an inch in diameter, and 74
inches deep. At the upper end of this bar and on one of its
sides about six-tenths of an inch in length of its substance is
cut away to the depth of half the diameter of the bore. When
a bar of any metal 6} inches long is dropped into this cavity,
it rests against its solid end; and a cylindrical piece of porce-
lain about 14 inch Jong, which I shall call the index, is placed
upon the top of it, which projecting into and beyond the open
part, is firmly confined to its place by a ring, or strap of pla-
tinum ; which passing round the black-lead bar and over the
piece of porcelain, is made to press upon the latter with any
required degree of tension by means of a small wedge of por-
celain inserted between the bar and the strap on the side of
the former. It is obvious that when such an arrangement is
exposed to a high temperature, the metallic bar will force the
index forward to the amount of the excess of its expansion
over that of the black-lead, and that when again cooled, it will
be left at the point of greatest elongation. It may also be
observed, that the exact indication of this amount is not in the
slightest degree interfered with by any permanent contraction
which the black-lead may undergo at high degrees of heat;
as any such contraction will take place at the moment of the
greatest expansion of the metal, and the index will still mark
its point of furthest extension upon this contracted basis.

The problem now consists in the accurate measurement of
the distance which the index has been thrust forward from its
original position; and although the amount can in any case
be but small, there is no reason why it may not, be determined
with the same precision as is now commonly attained in similar

quantities

Jor Measuring the Expansions of Solids, &¢. 197

quantities in astronomical and geodetical operations. For
this purpose the scale is constructed of two rules of brass,
accurately joined together at a right angle by their edges, and
fitting square upon two sides of the black-lead bar, and of
about half its length. At one end of this double rule a small
plate of brass projects at a right angle, which plate, when the
two sides of the former are applied to the two sides of the re-
gister, is brought down upon the shoulder formed by the notch
cut away at its upper end, and the whole may be thus firmly
adjusted to the black-lead bar by three planes of contact.

On the outside of this frame another brass rule is firml
screwed down, which projecting beyond it, and bending a little
so as to bring its end opposite to the cavity in the black-lead
bar when applied to it, supports a moveable arm exactly 54
inches long, turning at its fixed extremity upon a centre, and
at its other carrying an arc of a circle, accurately divided into
degrees and thirds of a degree, whose radius is exactly 5 inches.
At the centre of this circle upon the arm, and of course at the
distance of half an inch from the centre of motion, another
lighter arm is made to turn, one end of which, being the exact
radius of the circular arc, carries a nonius with it, which moves
upon the face of the are and subdivides the former graduation
into minutes. ‘The other end crosses the centre; and at the
exact distance of one-tenth of the radius, or the distance be-
tween the two centres of motion, terminates in an obtuse steel
point turned inwards at a right angle. These graduations
and distances are laid down with the greatest precision by
Mr. Troughton’s dividing engine. This part of the apparatus
may be regarded as a pair of proportional compasses attached
to the end of the brass rule and frame, whose longer legs
carrying the arc and nonius are to its shorter as ten to one;
and the opening of the latter being regarded as a chord of a
small circle, is magnified in the same proportion by the for-
mer, and measured upon the scale. A small steel spring let
into the larger arm is made to press upon the smaller, so as
to adjust the nonius to the commencement of the graduation ;
and when forced back it tends to restore it to its original
position.

The annexed figures, in which all the parts are drawn of
their real dimensions*, will assist the comprehension of the
preceding description. Plate II. fig. 1. represents the scale.
A A is the principal brass rule, upon the under side of which
the frame a a a aaa isadjusted by the screws b 6, and which

_ * In our plate the pyrometer is represented about one third less than
its real dimensions,—Lv1v.
supports

198 Mr. Daniell on a New Register-Pyrometer,

supports upon its bent extremity c, the arm B moving upon
the centre d, and terminating in the arc of the circle e e.

C Cis the lighter arm moving upon the centre fupon the arm
B, and carrying at one end the nonius g, and.at the other the
steel point /, the distance of which from the centre fis exactly
half an inch or one-tenth of the radius fg, and equal to the
distance of the two centres fd. 7 is a small lens represented
as lying down, but which may be raised by the centres & and Z
perpendicularly above the nonius to facilitate the reading.
m m is the steel spring, which being fixed in a cavity cut out
of the arm B, presses upon a small pin 2 on the arm C, and
throws the radius back to the commencement of the arc.

Fig. 2. represents the register. D D D Dis the black-lead
bar, with its cavityo 0. At ppp p itis cut away to the depth
of half the bore. q q is the porcelain index, which is placed
upon the top of the metallic bar, and confined to its place by
the pressure of the platinum strap r acting by the force of the
small porcelain wedge s.

When an observation is to be made, the metallic bar is
placed in the cavity of the register, the index is to be pressed
down upon it and firmly fixed in its place by the platinum
strap and porcelain wedge. ‘The scale is then to be applied
by carefully adjusting the brass rules to the sides of the black-
lead bar, and fixing it by pressing the cross piece (a') upon
the shoulder: holding the whole together steadily in the left
hand, the moveable arm should be so placed that the steel
point (2) of the other leg of the compasses may rest upon the
edge of the porcelain index, against which it will be pressed
with some force by the spring: then moving the arm gently
forward with the right hand, the point will slide along the end
of the index till it drops into a small cavity (¢) formed for its
reception, and which exactly coincides with the axis of the
metallic bar in the register, and the centre of motion of the
compasses on the brass rule. The minute of the degree must
then be noted, which the nonius indicates upon the arc. A
similar observation must be made after the register has been
exposed to an increased temperature and again cooled; and
the number of degrees or minutes which the nonius will then
mark will, by a simple calculation from the known length of
the radii and angle, give the length of the chord comprised
between the original position of the compasses and the point
to which they have moved, or the distance which the index
has been forced forward. Such an operation appears complex
in the description, but is in fact extremely simple after a little
practice, and does not require more than a few seconds for its

performance. The scale of this pyrometer being completely
detached

for Measuring the Expansions of Solids, &c. 199

detached from the part which is exposed to the fire, obviates
one important objection which has always been made to other
contrivances of the same nature, from the uncertain degree of
heat and expansion to which they are liable; while the sim-
plicity of that part of the arrangement which alone is subjected
to great heats, renders it little liable to injury; and together
with the cheapness of the materials of which it is constructed,
occasions but a very trifling expense for replacing it when
injured.

The calculation of the absolute expansion of the bar indi-
cated by the scale may be performed as follows:—As radius
to double the sine of half the arc read off, and found in a table
of natural sines, so will the radius B be to the chord of the
same arc; and this divided by ten (the radius of B being ten
times the length of the radius f/) will give the length required.
Suppose the arc read off upon the scale to be 4°,

Radius. Sineof2°. — Inches. Inch,
then 10000000 : 0348995 X 2: : 5 : °3489950 — 10 = ‘0348995.

Now in working out this proportion it will be observed,
that the multiplication by 2 and by 5 being both constant
may, in conjunction with the division by 1°0, be omitted ; and
leaving out also the final division by 10, the case resolves itself
into seeking the sine of half the arc, read off upon the scale, in
a table of natural sines, and reading it as the decimal of an inch.

Moreover, the chords of small arcs are so nearly propor-
tional to their ares that, the number of degrees measured upon
the scale never exceeding 10, they may be considered without
sensible error as denoting equal increments of expansion. The
following short Table of the value of a degree, and minutes
of a degree, may therefore be useful in practice.

TaB.e I.
ao V, Inch.
ie Opes OOS oo
030 = *004386
020 = 00290
OTS" "O02Z1sS
010 = :*:00145
Oro =" "00072
0 2 = +*00029
Oo 1 = 00014

_ The chord of ten degrees derived from this Table by mul-
tiplying ‘00872 by 10 would therefore be -0872, whereas it is
more accurately ‘0871; but the difference being only ;5,555dth
of an inch may, in most cases, be disregarded.

{To be continued. |

XXVI. On

[ 200 ]

X XVI. On the Theory of the Compressibility of the Matter com-
posing the Nucleus of the Earth, as confirmed by what is known
of the Ellipticities of the Planets. By the Rev. J. CHauuis,
Fellow of the Cambridge Philosophical Society*.

Pk. YOUNG suggested that the increase of density towards

the centre of the earth, might be owing to the com-
pressibility of the material of which it is composed. Laplace,
adopting the suggestion, obtained, in an addition to a Memoir
on the Figure of the Karth (Mém. Acad. Scien. An. 1818) the
law of the increase of density in proceeding from the surface
to the centre, on the suppositions that the relation between the

2
pressure (p) and density (g) is expressed by p = ad ( 5 —1),

(@ being the density at the surface), and that the chemical
composition of the nucleus of the earth is the same throughout.
He found that on these suppositions the requisite degree of
compressibility, and the proportion of the density at the sur-
face to the mean density, were not by any means at variance
with what we know on these points by experience. ‘The cause
assigned in this theory for the increase of density towards the
centre, and the relation between p and g, are of so simple a na-
ture, that I have been induced to inquire how far the theory
is confirmed by what is known of the ellipticities of the planets.
I here repeat the investigation of Laplace, modified for the
purposes I have in view. Suppose the mass of the planet to
be spherical. If 7 be any distance from its centre, and eg =
$ (7), the attraction on a particle of the mass at a distance R
from the centre is Bh , the integral being taken
from r =0 to r= R. To express this force in the manner
in which terrestrial gravity is usually expressed, let M = the
earth’s mass, a = its radius, and g = 32} feet, the measure
of the accelerative force of gravity at the earth’s surface:
2 2 -
then ar : PART EMIS, is the force expressed as re-
quired. Suppose that f/7*d7r(r) = (r). Then attraction

(Aye fate x ee, Now —dp=AedR;

2
and —dp= — ae ede.
Ang a? (RK) —W(0 Qk’ od
Therefore a a ‘ pe w0) ia ae

* Communicated by the Author,
Hence

Rev. J. Challis on the Ellipticities of the Planets. 201

2 2
Hence ¥ (R) — (0) + onary , Ede = 0; and dif

2M (Rige aRd

ferentiating, R?¢ (R)+ Qneaee\ dR? ar aa) = 0.
ahiat =,

Qn 9 as

Hence finally, eae: + ¢Re=0, ¢ being eee P .

k? M
The integral of this gives a = ae » 4 being the value
of g at the centre. Legendre has calculated (Mém. Acad. Scien.
An. 1789), that according to this law of density, ifc = the

: 2 SUS ts
earth’s radius, and gc = = , the ellipticity would be 568° and
1

if gc = =, the ellipticity would be 379° But it is plain from the
nature of solid substances that gc cannot be so great as z, for
then g would be = 0. In proportion as the value of g Ris near
to x, the density is small, and decreases rapidly as R increases:
and because solid substances do not admit of this rapid change
of density, and at their surfaces possess a certain limited den-
sity, therefore it is probable that we shall not be far wrong by

assuming gc = of, In fact, this value gives an ellipticity

of aa to the earth, which is very near the experimental de-

termination.

If now we calculate the attractive force of Jupiter at his
equator, by means of the period of his fourth satellite, and
the law of the inverse square of the distance, we shall find
that the ratio of the centrifugal force at his equator to this

force is But because the law of the inverse square

1
11°95"
does not accurately hold by reason of the planet’s spheroidal
shape, this value requires a correction. When the correction
has been made according to the formula given in the Méc.

Céleste, liv. iii. art. 35, the ratio becomes The ratio

12°348°
of the centrifugal force to gravity at the equator of Saturn,
calculated from the period (79°33 days) and mean distance
(64°36 equatorial radii) of the extreme satellite, and from the
time (10" 15’) of Saturn’s rotation, will be found to be ane"
Correcting as before, the ratio becomes } nearly. Calcu-

N.S. Vol. 10. No. 57. Sept. 1831. 2D lating

202 Rev. J. Challis on the Ellipticities of the Planets.
lating now the ellipticities of Jupiter and Saturn by Clairaut’s

=, we shall find

Theorem, on the supposition that gc =

for Jupiter — and for Saturn. The measurements of
Professor Struve determine the ellipticity of Jupiter to be
ar , and Herschel obtained < for the ellipticity of Saturn.
It must be observed that the above calculations take into
account only the first power of the ellipticity, and therefore
cannot be very accurate with respect to Jupiter and Saturn,
the ellipticities of which are not very small. We may, how-
ever, affirm that the ellipticity of Jupiter accords very well
with the theory we are considering. ‘That of Saturn is consi-
derably less than what the theory gives. Herschel remarked
an anomaly in the shape of this planet, which, however, sub-
sequent observations have not yet confirmed; viz. that the
equatorial diameter was not so large as a diameter about mid-
way between the equatorial and the polar. It would seem, if
this be true, that some cause has operated to compress the
parts about the equator. The same cause would account for
an ellipticity less than what our theory requires. Possibly
the rings may have something to do with this.

Venus, Mercury, and the Sun, in as much as they possess
no ellipticity discoverable by instruments, do not contradict
the theory. But Mars forms an exception. Its ellipticity is

: ; 1 :
ascertained by observation to be wei whereas the ratio of the

centrifugal force to gravity at its equator, which ratio differs
little from the ellipticity that the theory gives, will be found
1
to be 5a
the earth, +1294 the ratio of the volumes, and 24°67 hours the
period of its rotation. The great ellipticity of this planet,
considering the time of its rotation and its small size, is re-
markable, and seems not to be in accordance with Clairaut’s
Theorem, unless we suppose the gravity of the planet to di-
minish in passing from the equator to the pole.

If the cause assigned in this theory be sufficient to account
for the increase of the density of a planet towards its centre,
then on the supposition that the nuclei of the planets are all
as to chemical composition homogeneous, and are similarly
constituted, though of different mean densities, the equation

by taking *1386 for the ratio of its mass to that of

~
\

sel } re . . .
Gorm) = ought to be nearly true for all, since it is nearly

true

Rev. J. Challis on the Ellipticities of the Planets. 203

true for the earth. Let us see what will follow from sup-

posing this equation to be generally true. If the mean den-

sity of the earth be d, then M = pees and g? = BRS
y Bee tea 2. kas

Now the velocity (V) of propagation in a medium in which
2 —
p= ee —1), is = / 20, where the density is ® This

may be shown by a separate consideration of this particular
case, or be inferred from a general proposition respecting the
velocity of propagation, which I gave in the Phil. Mag. and
Annals of Philosophy, for May 1830*, where it was proved
that if p + C =a?e'*", V may be found from the equation

V?— a e"(1l+n)=0. We have then, ale = . ;gf=
3g8 | xe G5 ae eed
Viad? and g*c?, or anak i waite Now Laplace has

calculated that according to this theory the ratio of the mean
density to the density at the surface of the earth is 2°42; and
according to our supposition the same ratio holds true for the
planets.

o 2
Therefore if D = the mean density of the planet, a = 7
2 2 . . =
or ae =e 54 nearly. Hence if v = the velocity of pro-

pagation in the material which composes the nucleus of the

2 :
earth, z f= 51, 0rv= es ca : v being calculated

from this, is found to be 10°13 times the velocity of propaga-
tion in air:—a result far from being improbable. Generally,

ae g's Vig ee he Sy ee a
Wan = at Whence goles aig ft artic Pres

- ve Me m being the mass of the planet, M of the earth.

* I have there shown that, the velocity of uniform propagation
__ the velocity in the medium

F Maoriiolag ef thadensty: This equation bears the same relation to
space
time
motion itself, and will not seem unimportant to those who consider that
the one phanomenon is nearly as frequent as the other. As the proposi-
tion is quite new, and in some degree contradicts the received mode of
determining the velocity of propagation, it is not likely to meet with im-
mediate attention: I have therefore adverted to it here,

2 D2 The

the propagation of motion, as the equation, uniform velocity = x

204 Rev. J. Challis on the Ellipticities of the Planets.

The following values of a are calculated from the masses of

the bodies of our system, as given by Laplace. For the Sun,
54°31; Jupiter, 5°33; Saturn, 3:06; Uranus, 1:97; the Earth,
1; Venus, ‘981; Mercury, *651; Mars, -5; the Moon, :23.
It is observable that the order of magnitude of these quan-~
tities is the same as the order of the bodies arranged accord-
ing to their masses. It follows, therefore, from our theory,
that because in the greater masses the velocity of propagation
is greater, the materials of which they are composed possess
greater elastic force. This may be owing, not to any differ-
ence in the constituent elements, but to a greater degree of
proper caloric, or of the force, whatever it be called, by which
the constituent atoms are held in their positions relatively to
each other. For it is not unreasonable to suppose that the
proper underived caloric of any mass, such as we know exists
in the earth and forms the principal part of its caloric, is some
function of the mass, and is specifically greater as the mass is
greater. The Sun, which is the largest, is the hottest body
of our system. According to this view, if there be granite at
the surface of the moon, it will be more compressible than
the granite of the earth; it will possess both a density and a
compressibility depending on the mean density and compres-
sibility of the moon’s nucleus.

The theory we have been considering requires us to believe
that the interior of a planet is solid, and not fluid. On the
supposition of fluidity, it would be difficult to account for the
contradiction presented by Mars to Clairaut’s Theorem. May
we not conjecture, that this planet is hollow about its centre,
or in the direction of its axis? Generally speaking, the least
bodies of the solar system are the densest, if we set aside the
satellites, which seem to partake of the density of their pri-
maries. But Mars is not so dense as Mercury, Venus, or the
Earth. This fact favours in some degree the conjecture. .

Assuming the truth of our theory, we may readily conceive
that any change in the state of the internal heat of the earth,
would give rise to great changes at its suxface, and perhaps
produce effects like those exhibited by geological phano-
mena.

Upon the whole, a review of the planets seems to favour
the idea, that any increase of density towards their centres, is
owing either wholly, or at least in part, to the compressibility
of the matter of which their nuclei are composed.

Papworth, St, Everard, Aug. 10, 1831.

XXVIII. Analysis

[ 205 ]

XXVII. Analysis of some Salts of Mercury. By R. Pur.utes,
E.RS. L. & E. &c.

W HEN two parts of mercury are heated, for a short time,

with three of sulphuric acid, some protosulphate of
mercury is formed ; but if the heat be continued, the mercury
is converted almost entirely into bipersulphate, even before
the evolution of sulphurous acid gas ceases, or the whole of
the metal is dissolved. When this bipersulphate of mercury
is put into water it is decomposed, and a yellow precipitate,
formerly called turpeth mineral, is thrown down.

This salt was, I believe, first minutely examined by Four-
croy (Annales de Chimie, tom. x. p. 109.), and according to his
analysis, it consists of

Salphuric Cid 5 2.5secscscecscssssscee 10
MECrenny Gsivse. fecevescosveusneneeseme" 16
OXYGEN. veceecscccsveccsccccscrsccsese I]
WUCAUCR cas dadpivea seta de sinlid aviedactin stan chi Ss

100
MM. Braamcamp and Sequeira (Ann. de Chimie, tom. liy.
p. 123.) give as the result of their analysis,
Si WRNIG ACI a. cee suodushaasecede, 19
Peroxide of mercury ..........- aees Naa.
Loss, attributed to moisture ...... 00°3

100:0
Dr. Thomson (System, vol. ii. p. 660.) observes, that sup-
posing it to be a compound of 1 atom acid +1 atom per-
oxide, its constituents will be
Sulphuric acid..... Sapasactsvabsonen Mantes
Peroxide of mercury .......se.s0008 84°38

100-00

In his Attempt, &c. (vol. ii. p. 403.) also Dr. Thomson con-
siders this to be the true composition of this salt. Wishing,
however, to determine its nature, as well as that of the salt re-
maining in the solution from which it is precipitated, I put
200 grains of bipersulphate of mercury into about a quart of
cold water; the yellow sulphate precipitated weighed 141-1
grains; the solution was then heated, by which 8-4 grains
more were obtained ; afterwards sulphuretted hydrogen threw
down 14°5 of bisulphuret of mercury.

To ascertain the composition of the yellow sulphate, I heated
100 grains in a solution of soda; the peroxide of mercury
separated weighed 86°9 grains; to the solution, after super-
saturation with muriatic acid, muriate of barytes was added, and

37°3

206 Mr. R. Phillips’s Analysis of some Salts of Mercury.

37°3 grains of sulphate were precipitated, equivalent to 12°6
of sulphuric acid One hundred grains, therefore, yielded of
Sulphuric acid ........0sesseeees coe 126
Peroxide of mercury .'......+00+6. 86°9

Loss See veseoseoesesscsoseseosecsses eee °5

100°0
I ascertained the quantity of peroxide of mercury also, by
decomposing the salt with sulphuretted hydrogen; 100 grains
ave 94°8 of bisulphuret of mercury = 88-2 of peroxide.
Taking the mean of these experiments, the salt consists of
Sulphuric acid). ...ececccseossesse 19°6
Peroxide of mercury............ 87°5

100°1
I therefore consider the yellow sulphate of mercury, as a
subpersulphate constituted of

Three atoms of sulphuric acid (40x 3) = 120 or 12-2
Four atoms of peroxide of mercury (216 x4) = 864 87°8

——————

984 100°0
or it may be regarded as consisting of

Two atoms of persulphate of mercury (804432) = 512
One atom of dipersulphate.......s0008 (40+432) = 472

984

This however is so unusual an atomic constitution, that I
have not admitted its existence until after repeated analyses ;
it will be observed, that if we add the oxygen to the mercury,
in Fourcroy’s analysis, the resulting peroxide will amount
to 87, with which the results of my experiments very nearly
agree.

With respect to the sulphuric acid and the peroxide of mer-
cury remaining in solution, and which have been supposed to
constitute a peculiar supersalt ; it may be observed, that when
four atoms of bipersulphate of mercury are acted upon by
water, a compound of three atoms of acid and four atoms of
oxide is precipitated, while five atoms of sulphuric acid re-
main in solution: this acid, however, prevents the decompo-
sition of the whole of the bipersulphate by dissolving a por-
tion of it; the quantity remaining in solution depends, to a
certain extent, upon that of the water employed ; thus, when
using a quart of water, as in the above related experiment,
nearly 150 of the yellow subpersulphate were precipitated
from 200 of the bipersulphate, but when only half the quan-
tity of water was used, 155 were obtained from an equal

weight :

Mr. R. Phillips’s Analysis of some Salts of Mercury. 207

weight: in the former experiment, therefore, about one-tenth
of the bipersulphate, and in the latter rather less, remained
undecomposed.

Having some reason to suppose that the compounds of
carbonic acid and mercury had not been sufficiently examined,
I collected all the evidence on the subject, which I have been
able to obtain from the numerous authors whom I have con-
sulted. Dr. Thomson (System, vol. ii. p. 658.) says; * Car-
bonic acid does not attack mercury, but it may be combined
with its oxide by pouring an alkaline carbonate into nitrate
of mercury. The precipitate in that case is a white powder,
composed according to Bergman of

DACTEULY sccencsseccvesatstess, GU'9
Oxygen and acid.......... 91

100°0
** Supposing the carbonate a compound of 1 atom carbonic
acid +1 atom peroxide of mercury, it will consist of

Caniinic AiG « cacateee se cade cass ts Oe
PETRI O esp at tp e¥eo scones cdecneest GO 1G

100:00.”

It must however be very evident that the salt obtained by
Bergman was not a percarbonate so constituted ; and pro-
bably it was not a percarbonate at all; for 90-9 of mercury
require nearly 7°3 of oxygen for conversion into peroxide, and
consequently there is left only 1°8 for carbonic acid: if we
suppose it a protocarbonate, it must consist of about 90°5 prot-
oxide and 9°5 carbonic acid; but for reasons, which I shall
presently state, I am inclined to believe that it contained no
carbonic acid whatever.

In his Attempt &c. (vol. ii. p. 397.) Dr. Thomson does not
mention any percarbonate of mercury; but he informs us that
he obtained a white protocarbonate of mercury, by adding car-
bonate of soda to a solution of nitrate of mercury ; the preci-
pitate lost 14°44 per cent. by solution in nitric acid, and Dr.
Thomson considers it, therefore, as a sesquiprotocarbonate of
mercury, composed of

One atom and a half of carbonic acid 33 or 13°7
One atom of protoxide of mercury 208 — 86°3

241 100°0
Although, as already mentioned, I have referred to many
chemical writers, for evidence as to the existence and com-
position of protocarbonate of mercury, yet except what I have
quoted from Dr. Thomson, my an have been attended
with

208 Mr. R. Phillips’s Analysis of some Salts of Mercury.

with but little success; it is indeed true, that Berzelius (Essai
sur la Théorie des Proportions Chimiques, table, p. 21.) states,
that what he calls carbonas hydrargyrosus, consists of 9°47 car-
bonic acid +90'53 protoxide of mercury, or an atom of each;
but this, I take it for granted, is merely theoretical composi-
tion.

Berthollet (Mémoires d’ Arcueil, tom. iii. p. 89.) after men-
tioning the precipitation of pernitrate of mercury, by carbo-
nate of soda, to which I shall again advert: says, ‘ On a fait
la méme expérience avec une dissolution nitrique de prot-
oxide de mercure. Le précipité était d’un jaune clair; il
a fait, aprés avoir été bien lavé, une vive effervescence avec
Vacide nitrique. Lorsqu’on pousse fort loin les lotions, il prend
une couleur noiratre; et méme sa surface se noircit lorsqu’
on le laisse sous l’eau;” and he afterwards adds, “ le prot-
oxide se combine avec lui, [l’acide carbonique, | et peut former
un carbonate, lequel cependant peut étre décomposé par la
seule action de l’eau qui lui enléve l’acide carbonique, quoique
difficilement.”

Upon considering these statements, Iapprehend that Berthol-
let took the yellow precipitate for a carbonate, and the black
one for protoxide of mercury derived from its decomposition.

To procure protocarbonate of mercury, I mixed a solution of
carbonate of potash with one of protonitrate of mercury; the
precipitate at first produced was of a yellowish colour, and it
remained so until excess of the alkaline carbonate was added ;
it then became immediately of a dark colour, and eventually
as black as the precipitate formed by caustic potash: I have
therefore no doubt that the yellowish precipitate, first ob-
tained, was a subprotonitrate, and it dissolved in nitric acid
without effervescence; if the solution of the nitrate be added
to an excess of that of the carbonate, the precipitate is at
once black.

Two hundred grains of the precipitate procured with excess
of carbonate of potash, and dried by exposure to the air, were
dissolved in a weighed vial of dilute nitric acid; the loss of
weight was only 0°5 of a grain, and was evidently one of mani-
pulation merely ; this experiment I have repeated with similar
results.

Under these circumstances, I am of opinion that a white
or yellow protocarbonate of mercury cannot be formed; that
when the protocarbonate is precipitated it is ofa black colour,
but loses its carbonic acid by drying in the air.

Berthollet states that percarbonate of mercury cannot be
formed; he says indeed, correctly, that when bipermuriate of
mercury is treated with carbonate of potash, it is not enon

ut

Mr. J. Prideaux’s Experiments on Vanadiate of Ammonia. 209

but he is wrong in supposing that a percarbonate is not pro-
cured by adding the carbonate tc a solution of pernitrate:
I mixed solutions of these salts and obtained a precipitate,
which had an ochre yellow colour; it was dried by exposure
to the air, lost 4°4 per cent. by dissolving in dilute nitric acid,
and the solution when decumposed by soda gave 96:1 of per-
oxide; this salt is therefore a dipercarbonate, consisting of

Two atoms of peroxide of mercury (2162) = 432 or 95:2
Moe *AtOnY Oh Car wume ACO scrcevencscssscceesca == ee 4°8

454 100°0

XXVIII. Experiments on Vanadiate of Ammonia, and on
some other Compounds of Vanadium. By Mr. Joun Pri-
pEAUX, Member of the Plymouth Institution.

To the Editors of the Philosophical Magazine and Annals.
Gentlemen,

N the absence of detailed information on vanadium, a sum-
mary of experiments on the minute scale, on a portion of
vanadiate of ammonia, with which I was favoured in a letter
from Professor Berzelius, about a month since, may be not
unacceptable to your chemical readers. It was accompanied
by the information, that the atomic weight of vanadium is
855°87: that it combines with 1, 2 and 3 atoms of oxygen,
with the latter quantity forming vanadic acid; that by driving
off the ammonia, in an open vessel, the acid would be ob-
tained; and that by the same process, out of access of air, the
oxide would be produced.

The acid was the first subject of experiment. It is a dull
orange red powder, as described in your last Number, p. 152 ;
and the neutral salts it forms with alkaline and earthy bases
are white; which would hardly have been expected, consider-
ing the analogies of vanadium with chrome. With excess of
acid, however, they are yellow.

1. Vanadiate of potash is very soluble, and showed no dis-
position to crystallize, although evaporated slowly to dryness,
with frequent intervals of cooling, and afterwards redissolved
and left to spontaneous evaporation.

2. Vanadiate of soda is scarcely so soluble, but not more
disposed to crystallize.

3. The quantities employed amounting to only about 2 grains
of each salt, and the indisposition to crystallize being perhaps
due to the smallness of the quantity, the two solutions were
mixed and abandoned to spontaneous evaporation; the glass

N.S. Vol. 10. No. 57. Sept. 1831. 2E being

210 Mr. J. Prideaux’s Experiments on Vanadiate of Ammonia,

being occasionally made to vibrate, by striking on the edge
with a steel blade. The salts were, however, left on the glass
in two successive coatings; and a film, which had formed upon
the liquor, was studded beneath with brilliant globules, in
which no facets could be discovered by the microscope.

4. Vanadiate of ammonia is much less soluble, falling like
cream of tartar; it crystallized freely, on cooling, in acute
rhombic blades, like spear-heads.

5. Vanadiate of lime is still less soluble than the last, and
also crystallized in cooling. Crystalline form not unlike the
other, but thicker. The crystals were, however, so irregular
that but few could be defined.

6. Vanadiate of barytes. A solution of 1°482 grains of
vanadiate of ammonia, containing an atom of water, was mixed
with a solution of 1*312 grain of chloride of barium; the whoie
fluid became full of coagula, which settled, by boiling, into a
heavy white power. The residual liquor,was evaporated and
tested in the usual manner, and the decomposition was found
complete, so far as could be ascertained by this mode.

This precipitate affords a convenient method of recovering
the vanadic acid used in experiments. Mixing together the
various soluble vanadiates, solution of muriate of barytes
may be added, in slight excess, keeping the liquor hot. ‘The
vanadiate of barytes will quickly subside, and may be readily
washed. It is then (whilst quite recent) to be thrown into
40 or 50 parts of water, with a little excess of sulphuric acid;
when it will assume the deep orange colour of bi-chromate
of potash. It may digest for half an hour, with occasional
shaking ; when carbonate of ammonia is to be added, a small
lump at a time, letting it dissolve gradually, and mixing up
the liquor well before each addition, till the liquor is neutral,
avoiding much excess of the carbonate. ‘The precipitate will
then be white or will become so by boiling in the liquid; and
after washing to remove the adhering solution will not be
discoloured by fresh sulphuric acid. The liquor will contain
sulphate and vanadiate of ammonia, which are to be separated
by crystallization.

In the following experiments, solution of vanadiate of am-
monia was dropped into excess of the metallic solutions; the
persulphate of iron was prepared by heating protosulphate in
a test-tube with nitric acid, and contained that acid in excess;
—the others were all pure.

Immediate Effect. | After 12 Hours.
Sulpate § No precipitate; the liquid assumed | A pulverulent yellowish-
oe oi i, a greenish-yellow hue, becoming white precipitate; the
rene: gradually yellower and turbid. liquid orange yellow.

Green

and on some other Compounds of Vanadium.

colour, with a tint of green.

Immediate Effect.
ue An abundant flocculent dark slate
Ss bh A coloured precipitate, leaving the
oF alg liquid a paler shade of a similar

ae deep orange.

An orange-coloured precipitate at

oy Little or no precipitate; the liquid
| first contact, appearing greener
|

> pera on mixing with the blue solution ;
Copper settled, pale yellowish green,
: leaving the liquid a deeper shade
e yok the same colour.

Nitrate of Slight precipitate, pale salmon-co-

Cobalt. loured, liquid scarcely altered.
( Precipitate copious and heavy, of
saeete } nearly the same colour as the
hong above, settling paler and more

orange ; the liquid colourless.

Corrosive ( An orange precipitate; heavy,
Subli- settling yellower ; the liquid dull
mate. pale yellowish green.

Tartar

F dissolv n shaking ; teres
Emetic. ed on shaking ; and giving

J A brownish orange coagulum, re-
| that hue to the liquid.
L

211

After 12 Hours.

The precipitate unchang-
ed; the liquid greener,
like soluticn of sul-
phate of iron.

Unchanged.

The precipitate inclines
to orange colour; the

liquor remains _ yel-
lowish green.
Unchanged.
The precipitate almost

bleached, probably by
taking down excess of
lead.

The precipitate yellow;

liquid the colour of
chlorine.
The liquid opalescent,

dull pale green by re-
flected, and orange by
transmitted light; no
precipitate.

With vanadium as a base, the operations were more embar-
rassing. The oxides formed simultaneously, during the decom-
position of vanadiate of ammonia, and were difficult to separate.
One of them would seem to possess acid properties; and the
other to be partly converted into that in washing, and partly
to combine with it, forming a soluble compound, not precipi-
tated either by alkalies or acids*. The experiments were in-
conclusive, and the description of them must be very general.

Two portions of vanadiate of ammonia were decomposed
by heating in a close platinum crucible: one of them had been
recovered from former experiments, by precipitation with
barytes, as above described, and probably was not free from
sulphuric acid. The other had only been converted into
vanadic acid, redissolved in liquid ammonia and crystallized.

The first left an oxide of a deep blue or green colour, al-
most black. As it was supposed to contain sulphuric acid, it
was subjected to that acid, a drop of which turned the part
with which it lay in contact, light green; but the addition of a
few drops of water, after some hours, to give fluidity to the
whole, turned it deep blue, and syrupy, like undiluted sul-
phate of indigo. After twelve hours digestion, about 30 parts

* See our last Number, p. 152,—Eprv.

2h? more

212 Mr. J. Prideaux’s Experiments on Vanadiate of Ammonia,

more water were added, by which it was dissolved; and after
the subsidence of a yellow sediment the solution was pale
blue and strongly acidulous. The yellow sediment dissolved
in liquid ammonia, and was vanadic acid.

Carbonate of barytes in fine powder was added to the solu-
tion, to get rid of the excess of sulphuric acid. It produced little
effect, til] heat was applied; when effervescence took place,
the liquid became pistachio-green, and a flocculent dark olive
precipitate appeared; which gradually subsided, leaving the
liquor stiil blue and acidulous. Liquid ammonia did not
render it neutral, until a nearly black precipitate had fallen in
considerable quantity ; almost the whole of which was taken
up again by ammonia in excess.

In the second attempt the precaution was taken to add car-
bonate of ammonia in decomposing the salt, that the first
impression of heat might fill the crucible with an atmosphere
of that substance. ‘lhe remaining oxide, however, still con-
tained vanadic acid.

The solution in muriatic acid was blue, and could not be
neutralized without precipitation. Before neutralization took
place, liquid ammonia threw down an olive precipitate, and
made the liquor green, as above. ‘The green liquid, poured
off, and gradually neutralized with ammonia, gave a dark-
brown precipitate. The olive precipitate dissolved green, the
brown one blue, in muriatic acid.

After various experiments, in none of which did the oxide
of vanadium neutralize the acid employed, or yield with it
a crystallized salt, the solutions were mixed together, and
thrown into an excess of caustic potass, largely diluted. A
deep brown light precipitate fell, doubtless hydrate of the
oxide (most probably of the protoxide), leaving the liquor of
the same colour but transparent. A portion of this liquor was
withdrawn, and mixed with bi-carbonate of potash, when it
bleached, but without precipitating. The remainder was then
poured off and tried with muriatic acid, in slight excess, which
produced the green colour mentioned before, but without
disturbing the transparency. Caustic potash was then slowly
added, and whilst still acidulous, an inky precipitate fell; after
which a reddish brown one followed, when the liquor became
neutral. }

The reddish-brown and purple precipitates were both solu-
ble in acids, alkalies, and distilled water, and were therefore
difficult to wash ; both also reddened litmus paper. ‘The brown
precipitate became purple on the surface, when no great depth
of water lay on it, and at the same time square plates formed
in it, very small and thin, iridescent by reflected, but deep

yellow

and on some other Compounds of Vanadium. 213

yellow by transmitted light, which dissolved green in muriatic
acid without neutralizing it. None of these on being dissolved
in alkali and neutralized, produced precipitates in the metallic
solutions, similar to those with vanadiate of ammonia, and
therefore none appeared to contain vanadic acid; nor did I
succeed in obtaining a solution of the brown precipitate in an
acid, either neutral or which could be neutralized with am-
monia, without precipitation; a difficulty which I attribute to
its absorption of oxygen in washing. Attempts to obtain more
of it by boiling the other oxides with de-oxydating substances
were also frustrated by the difficulty of separating it after-
wards.

The solutions and precipitates were then mixed with nitric
acid in excess, and boiled together to dryness; redissolved in
solution of potash and boiled until colourless ; slightly acidu-
lated with muriatic acid; precipitated with muriate of barytes ;
and reconverted into vanadiate of ammonia, as above. A small
bulb was then blown on a bit of glass tube, which was drawn
out at half an inch from the bulb, and cut off, in the con-
tracted part, so as just to allow the vanadiate of ammonia to
enter. This salt was mixed with about half as much carbo-
nate of ammonia, and put into the bulb, which it filled. The
orifice was then nearly closed, at a spirit lamp; the neck
thrust into the end of a quill, which was stuffed up with tow
from the other end, so as very much to impede the access of
air. ‘The bulb was then heated over a spirit lamp, till am-
monia ceased to pass off: yet the oxide thus prepared did
not yield either a neutral solution, or one disposed to crystal-
lize, with sulphuric acid; and contained itself a large propor-
tion of acid. Nor did it, after various experiments, give re-
sults which could elucidate those above related.

Vanadium gives, particularly in the reducing flame, a green
bead with borax, of a tint rather yellower than that from
chrome.

Upon the whole the brown powder appears to me to be
hydrate of the protoxide; the purple, a combination of that
substance with the deutoxide; and the crystals, the same com-
bination, but with the protoxide in larger proportion. The
deutoxide seems to possess acid properties; to be soluble in
acids as well as alkalies; and to yield, with metallic solutions,
precipitates different from those with vanadic acid. The oxide,
both brown and mixed,. dissolves blue in acids; but the so-
lution becomes green by the addition of alkali, though still
highly acidulous. ‘The square crystals dissolve green in acids,
and the water becomes green when lying upon the surface of
the oxide, as it changes to purple. Hence the solution of

protoxide,

214 Notices respecting New Books.

protoxide, in peroxide of vanadium, would appear to be green
when the latter is in excess. But I cannot claim much faith
for the inferences from these minute experiments, which
must be resumed (unless we have more precise information
in the meanwhile) if, by finding vanadium in our own neigh-
bourhood, I can obtain a larger supply. I have examined a
considerable number of phosphates and arseniates of lead,
in which Mr. Johnstone’s description led me to suspect that
substance; and some primitive iron ores, yielding a particu-
larly soft metal; but have not hitherto found any traces of
vanadium. Yours, &c.

Plymouth, Aug. 10, 1831. J. PripEaux.

XXIX. Notices respecting New Books.

The Life of Sir Humpury Davy, Bart. LL.D.late President of the
Royal Society, Foreign Associate of the Royal Institute of France,
&c. &c. By John Ayrton Paris, M.D. Cantab. F.R.S. &c.
Fellow of the Royal College of Physicians.

= 4 bate great end of biography,” Dr. Paris remarks, “is not to

be found, as some would seem to imagine, in a series of dates,
or in a collection of gossiping anecdotes and table talk, which,
instead of lighting up and vivifying the features, hang as a cloud
of dust upon the portrait ; but it is to be found in an analysis of
human genius, and the development of those elements, to whose
varied combinations, and nicely adjusted proportions, the mental
habits, and intellectual peculiarities of distinguished men may be
readily referred.”

Although we admit this to be a just description of the proper
aim and end of biography, yet we confess we should have great
pleasure in quoting from Dr. Paris a variety of anecdotes which
illustrate what he terms “superficial peculiarities ;’ for they are
not only amusing, but they tend, to a certain extent, to elucidate
the progress of Sir H. Davy’s genius in cultivating the science,
whose limits have been so greatly extended by the variety, spendour
and importance of his discoveries. In the present instance, how-
ever, so much is due to the merits of the philosopher, that we can
dwell but little upon the characteristics of the man.

Humphry Davy was born at Penzance in Cornwall, on the 17th
of December 1778 ; his ancestors it appears had long possessed a
small estate at Varfell, in the parish of Ludgvan, in the Mount’s
Bay, on which they resided. His father was a carver of wood; and
of him Dr. Paris observes, what indeed may be said of the father of
many an illustrious son, that he “is not able to discover that he
was remarkable for any peculiarity of intellect; he passed through
life without bustle, and quitted it with the usual regrets of friends
and relatives.” His mother, whose maiden name was Grace Millet,

appears

Notices respecting New Books. 215

appears to have possessed remarkable placidity of temper, and an
amiable and benevolent disposition.

When very young he was placed at the Grammar School in Pen-
zance, whence he went to Truro, where he finished his education.
Although quick and industrious in his school exercises, he was
found very deficient in the qualifications for the class of his age ;
but by industry and attention he subsequently acquitted himself to
the entire satisfaction of his master.

In his boyish days he was fond of romance, of writing verses and
ballads, of fireworks, shooting and fishing. The taste for poetry
increased with his years, and Dr. Paris has given some specimens of
his poetic talent which are not unworthy of his genius. At twelve
years of age he composed an epic poem, of which, however, not even
a fragment has been preserved. His love of fishing he always re-
tained: it appears, indeed, to have increased, rather than dimi-
nished with his years.—‘* His temper during youth,” says Dr. Paris,
‘‘ is represented as mild and amiable. He never suppressed his feel-
ings, but every action was marked by ingenuousness and candour.”

In February 1795 he was apprenticed to Mr. Borlase, a surgeon
and apothecary, and afterwards a physician at Penzance; and al-
though his mind had been for some time engrossed with philoso-
phical pursuits, it does not appear that he had any decided turn for
Chemistry, until after he had been placed with Mr. Borlase ; but he
then commenced the study of it with ardour. “ As far as can be
ascertained,” says Dr. Paris, “ one of the first original experiments
on chemistry performed by him at Penzance, was for the purpose
of discovering the quality of the air contained in the bladders of
sea-weed, in order to obtain results in support of a favourite
theory of light ; and to ascertain whether, as land vegetables are
the renovators of the atmosphere of land animals, sea vegetables
might not be the preservers of the equilibrium of the atmosphere
of the ocean. From these experiments he concluded, that the dif-
ferent orders of the marine Cryptogamia were capable of decom-
posing water, when assisted by the attraction of light for oxygen.”
He seems also to have paid attention to Geology while with Mr.
Borlase ;—during his walks his usual companion was a hammer, with
which he procured specimens from the rocks on the beach.—*« In
short,” observes Dr. Paris, “it would appear that, at this period, he
paid much more attention to philosophy than to physic; that he
thought more of the bowels of the earth than of the stomachs of
his patients; and that when he should be bleeding the sick, he was
opening veins in the granite.”

During his stay with Mr. Borlase he became acquainted with
Mr. Davies Gilbert (then Giddy), who accidentally hearing that he
was fond of chemical experiments, expressed a desire to have some
conversation with him; and during this he soon discovered ample
evidence of young Davy’s singular genius, and the consequence was
an offer of the use of his library or any other assistance he might
require for the pursuit of his studies.

In October 1798 Davy quitted Penzance to superintend the
Pneu-

216 Notices respecting New Books.

Pneumatic Institution at Bristol, established by Dr. Beddoes for the
purpose of investigating the medicinal powers of factitious airs or
gases. “It is now generally acknowledged,” says Dr. Paris, ‘ that
the Art of Physic has not derived any direct advantage from the
application of a class of agents, which undoubtedly held forth the
fairest promise of benefit.” ** The investigation, however,” he con-
tihues, “ into the nature and composition of the gases paved the
way to some new and important discoveries in science; so that to
borrow a Baconian metaphor, although our philosophers failed in
obtaining the treasure for which they so eagerly dug, they at least,
by turning up and pulverizing the soil, rendered it fertile. The
ingenuity of the chemist will for ever remain on record; the phan-
toms of physicians have vanished into air.”

In a letter to Mr. Davies Gilbert, dated Clifton, November 12,
1798, Davy says, ‘“‘ We are printing in Bristol the first volume of
the West Country Collections, which will I suppose be out in the
beginning of January.” Dr. Paris informs us that “the work an-
nounced in the above letter was published in the commencement
of the year 1799, under the title of ‘ Contributions to Physical and
Medical Knowledge, principally from the West of England; col-
lected by Thomas Beddoes, M.D.’”

The following are Dr. Paris’s observations on this work: ‘“ ‘The
first two hundred pages, constituting very nearly half the volume,
are the composition of Davy, and consist of essays ‘ On Heat, Light,
and the Combination of Light;’ < On Phos-oxygen, or Oxygen and
its Combinations ;’ and ‘ On the Theory of Respiration.’

‘¢ His first essay commences with an experiment, in order to show
that light is not, as Lavoisier supposed, a modification or an effect,
of heat, but matter of a peculiar kind, suz generis, which, when
moving through space, or in a state of projection, is capable of be-
coming the source of a numerous class of our sensations.”

«A small gunlock was armed with an excellent flint, and on
being snapped in an exhausted receiver, did not produce any light.
The experiment was repeated in carbonic acid, and with a similar
result. Small particles were in each case separated from the steel,
which, on microscopic examination, evidently appeared to have un-
dergone fusion. Whence Davy argued, that light cannot be caloric
in a state of projection, or it must have been produced in these ex-
periments, where heat existed to an extent sufficient to fuse steel.
Nor, that it can be, as some have supposed, a vibration of the ima-
ginary fluid ether ; for, granting the existence of such a fluid, it
must have been present in the receiver. If, then, light be neither
caloric in a state of projection, nor the vibration of an imaginary
ether, it must, he says, be a substance suz generis.” ~

** With regard to caloric, his opinion that it is not, like light,
material, has been already noticed. In the present essay he main-
tains the proposition by the same method of reasoning as that by
which he attempts to establish the materiality of light, and which
mathematicians have termed the ‘ reductio ad absurdum.’ ”

“In his chapter on Light and its Combinations,” he indulges in

specu-

Notices respecting New Books. 207

speculations of the wildest nature, although it must be confessed
that he has infused an interest into them which might almost be
called dramatic. They are certainly highly characteristic of that
enlightened fancy, which was perpetually on the wing, and whose
flight, when afterwards tempered and directed by judgement, en-
abled him to abstract the richest treasures from the recesses of
abstract truth.”

‘«« Taking it for granted that caloric has no existence as a ma-
terial body, or, in other words that the phenomena of repulsion do
not depend upon the agency of a peculiar fluid, and that on the
contrary, light is a subtile fluid acting on our organs of vision
only when in a state of repulsive projection ; he proceeds to examine
the French theory of combustion; the defects of which he con-
siders to arise from the assumption of the imaginary fluid caloric,
and the total neglect of light. He conceives that the light evolved
during combustion previously existed in the oxygen gas, which he
therefore proposes for the future to call PHos-oxYGEN.”

«In following up this question, he would seem to consider light as
the Anima Mundi, diffusing through the universe not only organi-
zation, but even animation and perception.”

«« Phos-oxygen, he considers as capable of combining: with addi-
tional proportions of light, and of thus becoming ‘luminated phos-
oxygen!’ From the decomposition of which, and the consequent
liberation of light, he seeks to explain many of the most recondite
phznomena of nature.”

“ We cannot but admire the eagerness with which he enlists
known facts into his service, and the boldness with which he ranges
the wilds of creation in search of analogies for the support and il-
lustration of his views. He imagines that the phos-oxygen when
thus /uminated, must necessarily have its specific gravity consider-
ably diminished by the combination, and that it will therefore oc-
cupy the higher regions of the atmosphere; hence, he says, it is
that combustion takes place at the tops of mountains at a lower
temperature than in the plains, and with a greater liberation of light.
The hydrogen which is disengaged from the surface of the earth,
he supposes will rise until it comes into contact with this dwminated
‘acne de when by its attracting the oxygen to form water, the

ight will be set free, and give origin to the phznomena of fiery
meteors at a great altitude.”

“The phaznomena termed ‘ Phosphorescence,’ or that ]Juminous
appearance which certain bodies exhibit after exposure to heat, is
attributed by this theory to the light, which may be supposed to
quit such substances as soon as its particles have acquired repulsive
motion by elevation of temperature.’—* The eiectric fluid is con-
sidered as light in a condensed state, or, in other words, in that
peculiar state in which it is not supplied with a repulsive motion
sufficiently energetic to impart projection to its particles; for he
observes, that its chemical action upon bodies is similar to that of
light; and when supplied with repulsive motion by friction, or by
the contact of bodies from which it is capable of subtracting it, it

N.S. Vol. 10. No. 57. Sept. 1831. 2k loses

218 Notices respecting New Books.

loses the projectile form, and becomes perceptible as light. It is
extremely probable, he adds, that the great quantity of this fluid
almost every where diffused over our earth is produced by the con-
densation of light, in consequence of the subtraction of its repul-
sive motion by black and dark bodies; while it may again recover
the projectile force by the repulsive motion of the poles, caused by
the revolution of the earth on its axis, and thus appear again in the
state of sensible light; and hence the phenomenon of the Aurora
Borealis, ov Northern Lights.”

«In considering the theory of respiration, he supposes that phos-
oxygen combines with the venous blood without decomposition, but
that on reaching the brain, the light is liberated in the form of
electricity, which he believes to be identical with the nervous fluid.
On this supposition, sensations and ideas are nothing more than
motions of the nervous ether ; or light exciting the medullary sub-
stance of the nerves and brain into sensitive action !”

“ He thinks it would be worth while to try, by a very sensible
electrometer, whether an insulated muscle, when stimulated into
action, would not give indications of the liberation of electric fluid,
although he suspects that in man the quantity is probably too small,
and two slowly liberated, to be ascertainable. In the torpedo, and
in some other animals, however, it is unquestionably given out per-
ceptibly during animal action.”

«‘When any considerable change takes place in the organic matter
of the body, so as to destroy the powers of life, new chemical at-
tractions and repulsions take place, and the different principles of
which the body is composed enter into new combinations. In this
process, which is called putrefaction, Davy, in pursuance of this
theory, thinks that in land animals the latent heat of the system
enters into new combinations with oxygen and nitrogen, but that
in fish no such combinations occur, and hence the luminous appear-
ance which accompanies their putrefaction.”

Dr. Paris very justly characterizes these essays as extraordinary ;
but ‘I am not quite sure,” he adds, “ that amidst all the meteors
of his fancy there may not be a gleam of truth. I allude to his
theory of Respiration: it certainly does not square with the phy-
siological opinions of the day ; nor did that of Newton, when he
conjectured that water might contain an inflammable element ; but
it was the refraction of a great truth, at that time below the hori-
zon.” We admit with Dr, Paris, that the theory of phos-oxygen and
luminated phos-oaygen has scarcely a parallel in extravagance and
absurdity, and with him we also “ happen to know that in after life
Davy bitterly regretted that he had so committed himself; any
allusion to the subject became a source of painful irritation.”—
This was precisely the effect produced upon him by the notice
which Chenevix took of his theory in his treatise on nomenclature.
After all, Dr. Paris rightly observes, “ the reader, however, will
be disposed to treat him with all tenderness when he remembers
that the author of these essays was barely eighteen years of age.”
In a letter to Mr. Gilbert, dated Clifton, February 22, 1799, he

gives

Notices respecting New Books. 219

gives an account of the discovery that two pieces of canes rubbed
together gave a faint light, which he shows was occasioned by the
silica contained in the epidermis. In the same letter he announces
a more important fact— I made a discovery yesterday, which
proves how necessary it is to repeat experiments. The gaseous
oxide of azote is perfectly respirable when pure. It is never dele-
terious but when it contains nitrous gas. I have found a mode of
obtaining it pure, and 1 breathed to-day, in the presence of Dr.
Beddoes and some others, sixteen quarts of it for near seven
minutes. It appears to support life longer than even oxygen gas,
and absolutely intoxicated me. Pure oxygen gas produced no al-
teration in my pulse, nor any other material effect; whereas this
gas raised my pulse upwards of twenty strokes, made me dance
about the laboratory like a madman, and has kept my spirits in a
glow ever since. Is not this a proof of the truth of my theory of
respiration? for this gas contains more light in proportion to its
oxygen than any other, and I hope it will prove a most valuable
medicine.”

In the year 1800, appeared in one octavo volume, ‘ Researches,
Chemical and Philosophical ; chiefly concerning Nitrous Oxide, or
Dephlogisticated Nitrous Air and its Respiration. By Humphry
Davy, Superintendant of the Medical Pneumatic Institution.’—This
is a work containing the results of great labour and numerous ex-
periments. Dr. Paris remarks that “it may perhaps appear ex-
traordinary to the reader of the ‘ Researches,’ that although they
were published not more than eighteen months after the appearance
of his ‘ Essays on Heat and Light,’ no allusion is made in them
either to his theory, or his new nomenclature. In relating his ex-
periments upon respiration, he employs the conventional janguage
of the schools, and the word ‘ phos-oxygen’ does not once occur
in the volume. This is fully explained in a communication made
by him to Mr. Nicholson, and which was printed in his Journal a
short time after the publication of his Essays in the West Country
Contributions; in which he says, ‘As facts have occurred to me
with regard to the decomposition of bodies, which I had supposed
to contain light, without any luminous appearance, I beg to be con-
sidered as a sceptic with respect to my own particular theory of
the combinations of light, until 1 shall have satisfactorily explained
these anomalies by fresh experiments. On account of this scepti-
cism, and for other reasons, [ shall in future use the common
nomenclature ; excepting that, as my discoveries concerning the
gaseous oxide would render it highly improper to call a principle,
which in one of its combinations is capable of being absorbed by
venous blood, and of increasing the powers of life, azote,—I shall
name it, with Dr. Pearson, Chaptal and others, NrrroGENe; and
the gaseous owide of azote | shall call Nrrrous OxipE.”

“There is one circumstance connected with the views enter-
tained in this work,” observes Dr. Paris, “‘ which must not be passed
over without notice. Jn several passages he advocates the theory
of the atmosphere being a chemical compound of oxygen and nitro-

2F2 gen;

220 Notices respecting New Books.

gen; whereas in later years he was amongst the first to insist upon
its being simply a mechanical mixture of these gases.” Soon
after the appearance of the ‘ Researches,’ Davy was invited by
Count Rumford to the Royal Institution, which had been recently
formed under his auspices ; he arrived at the Institution on the 11th
of March 1801, inthe capacities of Assistant Lecturer on Chemistry,
Director of the Laboratory, and Assistant Editor of the Journal of
the Institution : in about six weeks he was appointed Lecturer on
Chemistry instead of Assistant; and in May 1802 he was styled
Professor of Chemistry.

On the 2st of January 1801, Davy gave the introductory lec-
ture to the first regular course; this was exceedingly well received
by a numerous audience, and was printed ; he had previously given
occasional lectures, but this must be considered as the commence-
ment of his splendid career. This course of lectures, as appears
from a printed sy!labus, was divided into three parts :—the che-
mistry of ponderable substances ; the chemistry of imponderable
substances ; and the chemistry of the arts. From this period he
continued regularly to increase in fame and popularity ; his first
paper in the Journal of the Royal Institution is entitled ‘ An Account
of a New Eudiometer;’ this was simply a small graduated tube di-
vided into 100 parts, immersed into a solution of protosulphate or
protomuriate of iron, impregnated with nitric oxide: as Dr. Priestley
had not only employed this gas as a eudiometrical substance, but
had shown the power of sulphate of iron in absorbing it, Dr. Paris
very justly remarks, that this test “ can only be regarded as a con-
venient modification of that of Priestley, in which nitrous gas was
presented to the atmospheric air to be examined, without the inter-
vention of any third body.”

The Royal Institution Journal contains several other communica-
tions from him, under the titles of ‘ Observations on different me-
thods of obtaining Gallic Acid ;* ‘ On the Processes of Tanning,
&c.’ All the new facts were embodied in an elaborate memoir, and
read before the Royal Society, of which he was elected a Fellow on
the 17th of November, 1803; in 1801 he had communicated to the
Society his first paper, entitled ‘ An Account of some Galvanic Com-
binations, formed by single metallic plates and fluids, analogous to
the Galvanic Apparatus of M. Volta.’ After this followed the paper
to which we have above alluded, and then ‘An Account of some
Analytical Experiments on a Mineral Production from Devonshire,
consisting principally of Alumina and Water. The Rev. William
Gregor had detected the presence of fluoric acid in this substance.
“The subsequent experiments of Berzelius, however,” Dr. Paris
remarks, ‘‘ cleared away the obscurity in which the subject was still
involved. He showed that this mineral not only contained in its
composition a small portion of the neutral fluate of alumina, but he
demonstrated the presence of a subphosphate of that earth, to no in-
considerable amount. Much has been said of the error committed
on this occasion by Davy, in overlooking thirty-three per cent. of
phosphoric acid ; but the phosphate of alumina is a body that might

very

Nolices respecting New Books. 221

very easily have escaped notice at a period when mineral analysis was
in a far less advanced state than it is at present.” We profess utter
ignorance as to the parties who have said much on this occasion :
the mistake might be readily pardoned at all times by those ac-
quainted with the difficulties of chemical analysis ; this will be still
more readily admitted, when it is recollected that Berzelius himself,
certainly one of the most skilful analysts that ever existed, actually
overlooked sixteen per cent. of the same acid in uranite.

His next paper was entitled ‘An Account of analyzing Stones
containing a fixed Alkali, by means of Boracic Acid’: for this and
the above-mentioned papers the Society awarded him the Copley
medal. This communication was followed by the Bakerian lecture,
read on the 20th of November 1806. According to Dr. Paris, this
paper “‘ unfolded the mysteries of general voltaic action ; and as far
as theory goes, may be almost said to have perfected our knowledge
of the chemical agencies of the pile. This grand display of scientific
light burst over Europe like a spendid meteor, throwing its radiance
into the deepest recesses, and opening to the view of the philosopher
new and splendid regions.” The subjects investigated in this memoir
are arranged by Dr. Paris as follows :—the changes produced in
water by electricity; the agencies of electricity in the decomposi-
tion of various compound bodies ; the transfer of certain constituent
parts of bodies by the action of electricity; the passage of acids, al-
kalies and other substances, through various attracting chemical
menstrua, by means of electricity ; general observations on these
phenomena, and on the mode of decomposition and transition ; the
general principles of the chemical changes produced by electricity ;
the relations between the electrical energies of bodies and their
chemical affinities ; the mode of the action of the pile of Volta, with
experimental elucidations ; general illustrations and applications of
the foregoing facts and principles. Dr. Paris gives a_very able
analysis of this paper, which we should be glad to copy if our space
would allow. It is no small commendation of this paper that the
author received for it the prize of the French Institute.

Davy’s second Bakerian Lecture was read on the 19th of November
1807. Of this lecture Dr. Paris also gives an analysis, for which we
must refer to his book: to stamp the value and importance of this
communication, it would be sufficient to say that it announces the
discovery of the metallic bases of the alkalies, potash and soda. On
this subject Dr. Paris well remarks, ‘thus then was a discovery ef-
fected, and at once rendered complete, which all the chemists in
Europe had vainly attempted to accomplish. The alkalies had been
tortured by every variety of experiment which ingenuity could sug-
gest, or perseverance perform, but all to no purpose ; nor was the
pursuit abandoned until indefatigable effort had wrecked the patience
and extausted the every resource of the experimentalist. Such was the
disheartening, and almost forlorn condition of the philosopher, when
Davy entered the field :—he created new instruments, new powers,
and fresh resources; and Nature, thus interrogated on a different
plan, at once revealed her long cherished secret.”

It is observed by Davy in his Bakerian Lecture, that “an account of

the

222 Notices respecting New Books.

the manipulations employed and the difficulties overcome would ex-
ceed the limits of a lecture.” Well knowing how valuable every
minute circumstance is to the chemist, Dr. Paris searched into the
archives of the Institution ; the result of the examination of the
Laboratory Register, we shall give in Dr. Paris’s words: ‘“ It appears
from this register that Davy commenced his inquiries into the com-
position of potash on the 16th, and obtained his great result on the
19th of October, 1807 *. His first experiments, however, evidently
did not suggest the truth: he does not appear to have suspected the
nature of the alkaline base until his last experiment, when the truth
flashed upon him in the full blaze of discovery. His first note,
dated the 16th, leads us to infer that he acted on a solid piece of
potash, under the surface of alcohol, and several other liquids in
which the alkali was not soluble; and that he obtained gaseous
matter, which he called at the moment ‘ alkaligen gas,’ and which he
appears to have examined most closely, without arriving at any con-
clusion as to its nature. On the following day, he for the first time
would seem to have developed potassium by electric action on potash
under oil of turpentine, for the note records the fact of ‘ the globules
giving out gas by water, which gas burnt in contact with air ;’ and
then follows a query, ‘ Does it (the matter of the globules) not form
gaseous compounds with ether, alcohol, and the oils?’ Here, then,
he evidently imagined, that the matter of the globules, which he had
never obtained from potash, except when acted upon under oil of
turpentine, had formed gaseous cumpounds with the ether, alcohol
and oils, in his previous experiments, and given origin to that which
he had termed ‘ alkaligen gas.’ ”

«« He then leaves the consideration of this gas, and attacks the un-
known globules, which probably did not present any metallic ap-
pearance under the circumstances in which he first saw them, for
they must have been as minute as grains of sand. I rather think
that he commenced his examination by introducing a globule of
mercury, and uniting it with a globule of the unknown substance ;
for his note says, ‘Action of the substance on mercury, forms with
it a solid amalgam, which soon loses its alkaligen in the air ;’ and
from the note which succeeds, he evidently considered this alkaligen
(potassium) as volatile, as he says ‘it soon flies off on exposure to
the air.”

“ October ]9.—It is probable that in consequence of the property
which the unknown substance displayed of amalgamating with mer-
eury, he devised his experiment of the 19th. He took a small glass
tube, about the size and shape of a thimble, into which he fused a
platinum wire, and passed it through the closed end. He then put
a piece of pure potash into this tube, and fused it into a mass about
the wire, so as entirely to defend it from the mercury afterwards to
be used. When cold, the potash was solid, but containing moist-
ure enough to give it a conducting power ; he then filled the rest of
the tube with mercury, and inverted it over the trough; the appa-

* On the same day he decomposed soda, with somewhat different pha-

nomena,
ratus

Royal Society. 223

ratus being thus arranged, he made the wire and the mercury alter-
nately positive and negative.” Dr. Paris then gives an engraving
of the autograph account of the results, the substance of which is
as follows :—‘‘ When potash was introduced into a tube having a
platina wire attached to it ——so— and fused into the tube so as to
be aconductor, i. e. so as to contain just water enough, though solid,
and inserted over mercury, when the platina was made negative,
no gas wus formed, and the mercury became oxydated, and a small
quantity of the alkaligen was produced round the platina wire, as was
evident from its quick inflammation by the action of water. When
the mercury was made the negative, gas was developed in great quan-
tities from the positive wire, and none from the negative mercury,
and this proved to be pure oxygene.—A capitan Experiment,
PROVING THE Decomposition oF Porasu.”

On the subject of this great discovery, Dr. Paris observes, “ In
the progress of our ascent, it is refreshing to pause occasionally, and
to cast a glance at the horizon, which widens at every increase of
our elevation. By the decomposition of the alkalies and earths,
what an immense stride has been made in the investigation of na-
ture! In sciences kindred to chemistry, the knowledge of the com-
position of these bodies, and the analogies arising from it, have
opened new views and led to the solution of many problems. In
geology, for instance, has it not shown, that agents may have ope-
tated in the formation of rocks and earths, which had not been pre-
viously known to exist? It is evident that the metals of the earths
cannot remain at the surface of our globe ; but it is probable that
they may constitute a part of its interior ; and such an assumption
would at once offer a plausible theory in explanation of the pheno-
mena of volcanoes, the formation of lavas, and the excitement and
effects of subterranean heat, and might even lead to a general theory
in geology.”

[To be continued. ]

XXX. Proceedings of Learned Societies.

ROYAL SOCIETY.

June 2nd — PAPER was read, “ On the Caves and Fissures in

the Western District of the Mendip Hills.” By
the Rev. David Williams, A.M. F.G.S., Rector of the parishes of
Bleadon and Kingston-Seamoor, in the County of Somerset. Com-
municated by Davies Gilbert, Esq. V.P.R.S.

The first cavern described in this paper is situated at Uphill, at
the very western extremity of the Mendip Hills. Its present en-
trance is about midway in a mural face of transition limestone,
about a hundred feet high. The fissure leading into it is nearly
vertical, and was discovered by some quarry-men casually inter-
secting it. Some bones and teeth being found there, the author was
induced to pursue the exploration of the fissure; in the course of
which he discovered bones of the rhinoceros, hyena, bear, ox,
horse, hog, fox, polecat, rat and mouse, and also of birds. The bones

of

224 Royal Society.

of the animals of the larger species were so gnawed and splintered,
and evidently of such ancient fracture, that no doubt could exist of
the cave having been a hyena’s den, similar to Kirkdale and Kent’s
Hole. All the ancient remains were found in the upper regions of
the fissure, and were so firmly imbedded in the detritus, as not to
be extracted without difficulty with the pick-axe. Further on he
found a wet tenacious loam, abounding with an innumerable quan-
tity of bones, belonging exclusively to birds. After working six
days he came to a cavern, ten or twelve feet high, extending about
forty feet from north to south, and varying from eight to twenty
feet from east to west ; the floor of which was covered with bones
of sheep: and on digging into the mud and sand of which it con-
sisted, the bones of sheep, birds, cuttle-fish, and foxes, were disco-
vered. Some fine stalactites depended from the roof, and partial
spots of stalagmite appeared on the floor. Ina fissure that branched
from the mouth of the main entrance there were found, among the
sand, a piece of black Roman pottery, and two coins, one of Didius
Julianus, and the other of Julia Mammea, together with bones of
sheep, cuttle-fish, foxes, and birds.

The author considers that there exist evidences of the operation
of water at three distinct periods of time :—the first indicated by
the bones of the hyzna, and the other gnawed bones firmly im-
bedded in the diluvial detritus: the second, when sand was depo-
sited by the sea in the second fissure, that washed in through the
vertical chimney, and that inundated the whole valley up to Glas-
tonbury: the third irruption of the sea occurring within these fif-
teen hundred years, and choking up the adit from the level by which
the sheep and foxes had entered, floating in the bones of the cuttle-
fish, and depositing the thin crust of mud which covered the sand.
The coins and pottery he supposes to have been introduced through
this entrance from the level.

The author next gives an account of the Hutton caverns, situated
on the northern escarpment of the range, commonly called Bleadon
Hill. This cavern had been discovered some time ago and noticed
by Mr. Catcott in his “ Treatise on the Deluge:” but afterwards it
became inaccessible by the falling in of the roof and sides. The
author, led by some indications of pieces of ancient bones in the
rubbish of some old pits, sought for this cavern by sinking a shaft,
and succeeded in opening into it. The chambers he reached are
probably the western extremity of a very extensive range of ca-
verns, occurring in a region bearing marks of great disturbance,
abounding in chasms and fissures, and containing a great number
of bones. The principal of those discovered belong to the elephant,
tiger, hyena, wolf, boar, horse, fox, hare, rabbit, rat, mouse, and
bird. No trace of the bones of the ox were discovered here, al-
though in the cave at Banwell Hill, about a mile distant, they
abound; while, on the other hand, no vestige of the horse is met
with.

Among the remarkable specimens found in the Hutton caverns
were the milk-teeth and other remains of a calf elephant about two

years

Royal Society. 225

years old, and those of a young tiger just shedding its milk-teeth ;
and also the molares of a young horse that were casting their coro-
nary surfaces ;—the remains of two hyznas of the extinct species ;
and two or three balls of album grecum.

The Banwell caves, lying about a mile to the east of Hutton, are
next described. They are the property of the present Bishop of
Bath and Wells ; and contain remains of the bear, wolf, fox, deer,
and ox. Of the bear there are at least two species ; one of which
appears to be the Ursus speleus of Blumenbach, and must have
been an animal of immense size and strength. These remains were,
in general, not associated according to the animals they belonged
to, but indiscriminately dispersed : thus the head of a bear lay by the
femur of an ox, and the jaw of a wolf lay by the antler of a deer.
Hence the author infers that these bones, after accumulating for
ages, were carried in by a tumultuous rush of waters, and mingled
together before their final deposition. He concludes that the se-
veral animals whose remains are deposited in the Banwell and Bur-
lington caves belonged to a very different age and period from
those found at Hutton and Uphill.

An account is also given of two caves at Burrington Coomb,
lying about six miles to the east of Banwell, in one of which, though
similar in appearance to the caves already described, no ante-
diluvian remains of animals lave been found. Several human
skeletons, and flint knives and celts, were discovered there by Mr,
Williams ; from which it has been inferred that it had formerly been
used asa burying-ground. Inthe upper caverns, remains of the bear,
elk and polecat, were discovered; the two former evidently of the
extinct species.

June 9.—A paper was read, entitled “‘ Researches in Physical As-
tronomy.” By J.W.Lubbock, Esq., V.P., and Treasurer of the Royal
Society.

The author extends, in the present paper, the equations he has
already given for determining the planetary inequalities, as far as the
terms depending on the squares and products of the eccentricities, to
the terms depending on the cubes of the eccentricities and quantities
of that order, which he does by means of a table, similar to the one
given in his lunar theory ; and applies them particularly to the deter-
mination of the great inequality of Jupiter, or at least such part of it as
depends on the first power of the disturbing force. That part which
depends on the square of the disturbing force may, he thinks, be most
easily calculated by the methods given in his lunar theory. He re-
commends it as particularly convenient to designate the arguments of
the planetary disturbances by indices. The bulk of the paper is oc-
cupied by the tables, and by examples demonstrating their use.

A paper was read, “On the Theory of the Elliptic Transcendents.”
By James Ivory, A.M., F.R.S., &c.

Fagnani discovered that the two arcs of the periphery of a given
ellipse may be determined in many ways, so that their diflerence shall
be equal to an assignable straight line ; and proved that any arc of
a lemniscate, like that of a circle, may be multiplied any number

N.S. Vol. 10. No. 57. Sept. 1831. 3 of

226 Royal Society.

of times, or may be subdivided into any number of equal parts, by
finite algebraic equations. What he had accomplished with respect
to the arcs of the lemniscates, which are expressed by a particular
elliptic integral, Euler extended to all transcendents of the same class.
Landen showed that the arcs of the hyperbola may be reduced, by a
proper transformation, to those of an ellipse. Lagrange furnished us
with a general method for changing an elliptic function into another
having a different modulus; a process which greatly facilitates the
numerical calculation of this class of integrals. Legendre distributed
the elliptic functions into distinct classes, and reduced them to a re-
gular theory, developing many of their properties which were before
unknown, and introducing many important additions and improve-
ments in the theory. Mr. Abel of Christiania happily conceived the
idea of expressing the amplitude of an elliptic function in terms of
the function itself, which led to the discovery of many new and useful
properties. Mr. Jacobi proved, by a different method, that an elliptic
function may be transformed in innumerable ways into another similar
function, to which it bears constantly the same proportion. But his
demonstrations require long and complicated calculations ; and the
train of deductions he pursues does not lead naturally to the truths
which are proved, nor does it present in a connected view all the
conclusions which the theory embraces. The author of the present
paper gives a comprehensive view of the theory in its full extent, and
deduces all the connected truths from the same principle. He finds
that the sines or cosines of the amplitudes, used in the transformations,
are analogous to the sines or cosines of two circular arcs, one of which
is a multiple of the other; so that the former quantities are changed
into the latter when the modulus is supposed to vanish in the alge-
braic expression. Hence he is enabled to transfer to the elliptic
transcendents the same methods of investigation that succeed in the
circle : a procedure which renders the demonstrations considerably
shorter, and which removes most of the difficulties, in consequence of
the close analogy that subsists between the two cases.

A paper was read, entitled, “ An Experimental Investigation of the
Phenomena of Endosmose and Exosmose.” By William Ritchie, Esq.,
M.A., F.R.S., Professor of Natural Philosophy in the Royal Institu-
tion of Great Britain.

Mr. Porret had, in the year 1816, announced the discovery, that if a
vessel containing water be divided into two compartments by a dia-
phragm of bladder, and placed in the voltaic circuit, the water would
rise on the negative side above its level in the positive compartment.
M. Dutrochet discovered, that if alcohol be placed in one of the cham-
bers, and water in the other, without employing the voltaic battery,
the water will percolate through the bladder, and the fluid will rise in
the chamber containing the alcohol: an action to which he gave the
names of Endosmose and Exosmose, according to its direction with
regard to the side of the membrane considered ; comparing its two
sides to those of a Leyden jar in opposite electrical states, This
electrical theory has been combated by M. Poisson : but the true expla-
nation of this singular phenomenon does not appear to have been yet
given.

Royal Society. 227

The experiments of the author, of which an account is-given in this
paper, were made with a glass tube, about an inch in diameter, one
end being drawn out into a slender tube of the interior diameter of
one eighth of an inch, and having a piece of bladder tied over the
other end. When this Endosmometer, as it has been called, is by means
of a small fannel introduced into the narrow end filled with alcohol,
and immersed in water, the water penetrates through the blad-
der, and the spirit rises rapidly in the narrow stem. The author
found on trial that this action was apparently not affected by a pow-
erful current of voltaic electricity passed through the bladder, by in-
troducing positive and negative wires on both sides of it. On sub-
stituting a strong solution of sulphate of zinc for the alcohol, the same
negative result was obtained.

The author considers the action of the animal membrane to be the
consequence of its strong attraction for water, an attraction to which
it owes its hygrometric properties : while, on the other hand, the
membrane has no attraction for alcohol, which has itself a powerful
attraction for water. The water, therefore, finds its way easily through
the membrane, and uniting with the alcohol, is carried off by it, and
diffused through the liquid, making room for the other portions that
successively come over. Whalebone and quills have similar hygro-
metric properties, and may be substituted for membranes with the
same effect. All substances readily soluble in water give rise to the
phenomena of endosmose, on the same principle as alcohol, such as
gum, sugar, and salts. The phenomenon bears a striking resem-
blance to the rise of the sap in the capillary vessels of plants, both
being probably dependent on the same principle; the filamentous
texture of the roots performing the function of the membrane, and
the contained sap that of the attractive fluid; by the agency of which
the external moisture of the earth is imbibed and raised into the
interior of the plant.

June 16.—A paper was read, “On the Tides in the Port of
London.” By J. W. Lubbock, Esq., V.P., and Treas. R.S.

This paper contains a discussion of observations of the tides
made at the London Docks, and registered in various Tables, showing
the time and height of high water, not only at different periods of
the moon’s age, but also for the different months of the year, for
every minute of the moon’s parallax, and for every three degrees of
her declination. ‘The tables themselves were registered by Mr.
Dessiou of the Admiralty ; but the arrangement of the tables and
the methods employed are due to the author. The tides in the river
Thames are extremely regular; and as the rise is considerable, the
observations on them are easily made. Those at the London Docks
present an uninterrupted series from the opening of the Docks in
1804 to the present time ; which is more extensive than any extant,
with the exception only of that made at Brest by order of the French
Government. Some observations are also given of the tides made du-
ring one year at the East India Docks, under the superintendence
of Captain Eastfield, and which were undertaken at the suggestion
of the author, and made with extreme care.

2G2 The

228 Royal Society.

The author gives an account of the mode by which the several
tables were constructed ; and enters at length into the various ma-
thematical considerations which the subject involves.

The author was enabled, by the kindness of the Chairman and
Directors of the London Dock Company, to present to the Society
the books containing the complete series of original observations on
the tides referred to in this paper.

A paper was read, “On the Friction of Fluids.” By George
Rennie, Esq., V.P.R.S.

The object of the author in this paper is to trace the relation sub-
sisting between the different quantities of water discharged by
orifices and tubes, and the retardations arising from the friction of
the fluid. The results of the experiments hitherto made with a
view of ascertaining the effects of the friction attending the mutual
motion of solids and fluids, are exceedingly discordant, and there-
fore undeserving of confidence. Whether, for example, the retarda-
tion from friction be proportional to the surfaces, or to the velo-
cities, are points by no means satisfactorily determined.

The experiments of the author were designed to measure the re-
tardations experienced by solids moving in fluids at rest; and of
fluids moving over solids. For this purpose, he employed a cylinder
of wood, about eleven inches in diameter and two feet in length,
traversed by an iron axle, upon the upper part of which a small
pulley was fixed. A fine flexible silken cord was wound round the
pulley, at one end, and had a weight attached to the other end. A
frame was provided, allowing the apparatus to slide up and down;
and the cylinder to be immersed at various depths into the river
Thames. When the velocities were small, the retardation was found
to be nearly as the surface : but with great velocities it appears to
have but little relation to the extent of the surface immersed. The
resistances of iron discs and wooden globes revolving in water were
found to be as the squares of the velocities.

From the experiments made on the quantities of water discharged
by orifices of different shapes and sizes from vessels kept constantly
full, the author concludes, that they are in the ratio of the areas of
the orifices, independently of their shape ; and nearly as the square
roots of the heights. In pipes bent at various angles the retarda-
tion occasioned by the flexure was not in proportion to their num-
ber.

A paper was read, “ On the Sources and Nature of the Powers on
which the Circulation of the Blood depends,” By A. P. Wilson
Philip, M.D. F.R.S. L. & Ed.

In the first part of this paper the author discusses the opinions
which ascribe the powers that maintain the circulation in the veins
to the elasticity of the heart, the resilience of the lungs, and the
dilatation of the thoracic cavity in the act of inspiration. He shows
experimentally that the circulation continues unimpaired when all
those causes have ceased to operate; and that the very structure of
the veins, the coats of which are so pliable as to collapse by their
own weight, when empty, renders it impossible that the motion pF

the

———

Roological Society. 229

the blood could be maintained in them by any cause corresponding
to a power of suction in the heart,

The latter part of the paper is occupied by an inquiry into the
sources and nature of the powers which really support the circula-
tion of the blood. The capillaries, he observes, maintain the mo-
tion of their blood long after the heart has ceased to beat; this
motion not being immediately affected even by the entire removal
of the heart ; but being accelerated, retarded, or arrested, according
as the action of the capillaries is increased, impaired, or destroyed,
by agents of which the operation is wholly confined to the vessels
themselves, As the destruction of the heart does not immediately
influence the motion of the blood in the capillaries, so the action of
this organ, when in full vigour, can produce no motion of the blood in
the capillaries, when these vessels are themselves deprived of power.
Experiments are related with the view of proving that the arteries
and veins, and more particularly the latter, are also capable of car-
rying on the blood they contain, even in opposition to the force of
gravitation, with the greatest ease, and without the aid of any ex-
traneous power. With regard to the nature of the power exerted
by the blood-vessels, the author shows that the capillaries are as
readily influenced by stimulants and by sedatives, as the heart itself;
and that the arteries and veins may also be made to obey the action
of stimulants ; and further, that the power of the vessels bears the
same relation to the nervous system as that of the heart, which is
peculiar, and very different from the relation subsisting between
that system and the muscles of voluntary motion. From the whole
of the facts and experiments stated in this paper, the author de- ,
duces the conclusions, that the circulation is maintained by the
combined power of the heart and blood-vessels, and that the power
of both is a muscular power.

ZOOLOGICAL SOCIETY.
June 14, 1831. Joshua Brookes, Esq. in the Chair.

A letter addressed to the Secretary of the Society by Charles
Telfair, Esq., Corr. Memb. Z. S., dated Port Louis, December
15th, 1830, was read. It referred to previous unsuccessful
attempts on the part of the Society’s valuable correspondent to
transport from the Mauritius to England living Gowramies and
Tanrecs, and promised a repetition of the experiment. Mr. Tel-
fair states that he has now a pair of living Tanrecs fully grown
ready to send to England when he can place them under proper
care, ‘ They live on boiled rice, but will probably not exist long
upon that alone, as their natural food is chiefly composed of worms,
insects, lizards, and the eggs of snails, of which it would be difficult
to carry a sufficient supply in a living state on board ship. Fresh
supplies might, however, be obtained at Madagascar or the Cape of
Good Hope, at St. Helena, Ascension, and the Cape de Verd
Islands ; and the animals might thus arrive in good health in En-
gland, where they would probably survive for some time burrowing
under a dungheap, or living in straw in a bhot-house or green-

house,

230 Soological Society.

house. An opportunity would thus be furnished of observing their
habits. Inthe Mauritius they sleep through the greater part of the
winter, from April to November, and are only to be found when
summer heat is felt, which being generally ushered in by an electric
state of the atmosphere, the negroes (with whom they are a favour-
ite food) say they are awakened by the peals of thunder which
precede the summer storms or ‘pluies d’orage.’ Even in summer
they are not often seen beyond the holes in which they burrow,
except at night. Their favourite haunts are among the old roots
of clumps of bamboos. They have a very overpowering smell of
musk at all times, which is increased to an extraordinary degree
when they are disturbed or frightened: yet their flesh is considered
so savoury by the negroes that they are unwilling to sell those
which they catch, and would not exchange it for any other food,
except perhaps for the ‘ ourite,’ which is the Catfish hung up in
the sun until it acquires a most fcetid smell, tainting the atmosphere
to a great distance ; in this state it is a chief ingredient in their fa-
vourite ragout. This mode of living may be one of the causes of
the peculiar odour of the skin of the woolly-headed race, which no
ablutions can remove, and which is not less distinctive of their race
than the colour of the skin itself.”

Mr. Telfair then refers to the collection of Fishes last presented
by him to the Society, portions of which were exhibited at the
Meetings of the Committee on the 12th and 26th of April. He
is continuing his ichthyological collections, and states the proceed-
ing which he adopts in the preservation of the specimens to be as
follows. ‘‘ The moment the fish is caught it is thrown intoa tub of
rum; and the numbers are gradually augmented until there is no
further room and the spirit begins to acquire a slight smell of the
fish. They are then taken out; washed in fresh rum; and again
put into clean spirit. They are then ticketed and numbered with
lead and wire, and are ready to be put up in the preparation bottles
as opportunities for their embarkation offer: this is done with fresh
spirit also.” The success of this method was shown to be in many
instances almost complete, the fishes exhibiting great beauty and
brilliancy of colour. In some cases, however, it is less successful,
and even the same species varies considerably in its state of preser-
vation. Thus of the Julis decussatus, (Sparus decussatus, J.W. Benn.)
two specimens almost equal the brilliancy depicted in the ‘ Fishes
of Ceylon’ [Plate xiv.], while a third has parted with nearly the
whole of its colouring, and retains merely the markings. The iron
wire employed in affixing the leaden numbers has generally rusted
so as to stain the fishes where it has been in contact with them, and
has in some instances been so weakened by corrosion as no longer
to retain the lead.

Mr. Telfair concludes by referring to the neighbouring island of
Madagascar, and to the interest attaching to its natural productions
so far as they have been already investigated. He remarks how
imperfect this investigation yet is, and gives a historical sketch of
the various attempts made by European naturalists during the last —
twenty years, but few of which have been attended with even mode-

rate

Roological Society. 231

rate success. In several instances they have been fatal to the zealous
individuals who have devoted themselves to the pursuit, the climate,
especially that of the coast, being generally ill suited to Euro-
peans. A new attempt is about to be made under the auspices of
Mr. Telfair and the Mauritius Natural History Society, from which
he anticipates considerable additions to science, the individual se-
lected being well adapted for the purpose by long practice in col-
lecting and preserving specimens, and by being thoroughly accli-
mated to Madagascar, in which he has on several occasions resided
for a considerable time.

Mr. Owen, having had occasion to examine recently with Mr.
Yarrell the body of a Gannet, (Sula Bassana,)which died at the So-
ciety’s Garden, read his notes of the examination, They referred
chiefly to the situation and connections of the air-cells, and differed
in some particulars from the observations recorded by Montagu,
who states in the ‘Supplement to the Ornithological Dictionary’
[article Gannet], that “by reason of some valvular contrivance the
skin could not be artificially inflated through the lungs;”’ and adds,
“it is also clear that there is no direct communication between
the sides.”

“In the examination our attention was chiefly directed to the
air-cells, which in this bird, as inthe Pelican, have a most extensive
distribution, We commenced by gentle but continued inflation
through the érachea, a pipe having been introduced into the upper
larynx : in a short time the integuments of the whole of the lateral
and inferior parts of the body rose, and the air-cells seemed com-
pletely filled, especially that which is situated in front of the os

Jurciforme, Being thus satisfied that they all had a free commu-
nication with the chest, we next proceeded to see at what points
these communications took place, and in what degree the air-cells
communicated with each other. For that purpose the air-cells on
the left side of the body were Jaid open, and shortly after those of
the opposite side collapsed, indicating the existence of apertures of
communication, although the septum which ran along the middle
line of the body appeared at first sight imperforate. There was a
free communication between the lateral air-cells of the same side of
the body from the os furciforme to the side of the pelvis ; but the
air-cell in front of the os furciforme remained still tensely inflated.
The lateral air-cells had a free communication with the cavity of the
chest at the azilla, at which part the air had entered these cells
during the inflation. The pectoral muscles and those of the thigh
presented a singular appearance, being as it were cleanly dissected,
having the air-cells extended above and below them; the axillary
vessels and nerves also passing bare and unsupported by any sur-
rounding substance through these cavities. We traced the air-cells
down the side of the humerus, ulna, and metacarpal bone, into all of
which the air entered, and even into the bone corresponding to the
first phalanx, which agrees with what Mr. Hunter has deseribed
in the Pelican. (Animal (Econ. p. 92.)

“ As none of these proceedings had any effect on the air-cell in
front of the os furciforme, which still continued distended, it was

evident

232 Soological Society.

evident that inflation by the humerus could not have filled it except
through the medium of the lungs themselves. We next proceeded
to detach the integument from this air-cell to see its shape and ex-
tent ; this required to be done with great care, as it adhered pretty
closely to the skin and roots of the feathers: it was of a globular
form, about four inches in diameter, and communicated with the
thorax at its anterior aperture below the trachea.

« Numerous strips of muscular fibres passed from various parts
of the surface of the body, and were firmly attached to the skin; a
beautiful fan-shaped muscle was also spread over the external sur-
face of the air-cell anterior to the os furciforme. The use of these
muscles appeared to be, to produce instantaneous expulsion of the
air from these external cells, and by thus increasing the specific
gravity of the bird to enable it to descend with the rapidity neces-
sary to the capture of a living prey while swimming near the surface
of the water.

«« With respect to the general anatomy of this bird, it may be
observed that we found the two small glands at the termination of
the trachea, which are noticed by Montagu, and which exist in ad-
dition to the ordinary pair lying above the bronchig, The stomach
corresponded exactly with the figure given by Sir Everard Home
(Comp. Anat. pl. xlvi.), the pyloric orifice being provided with the
bilobed valve which is there represented, though not described in
the text ; it evidently opposes a too ready egress of the contents
of the stomach.”

Mr. Vigors exhibited a collection of African Birds which had
been presented to the Society by Henry Ellis, Esq., of Portland
Place. They consisted of about one hundred and thirty species,
many of them of extreme rarity and value, and a great portion un-
known to the cabinets of England. They came immediately from
Algoa Bay ; but were supposed to have been collected far in the
interior of the country. Mr. Vigors expressed his intention of lay-
ing before the Committee at an early Meeting, a descriptive cata-
logue of the whole collection, as well as whatever particulars he could
collect respecting the locality from which it was brought. He named
and characterized in the mean time the following apparent novelties
from the Insessorial Birds.

Turpus eurrarus. Turd. supern? olivascenti-brunneus, subtis sub-
rufescenti-albidus ; strigis tribus genarum, guttis rotundis pectoris
abdominisque, tectricumque alarum notis brunnescenti-atris ; tec-
tricibus alarum, rectricibusque tribus utrinque lateralibus ad apicem
albo notatis.

Statura paulo minor quam Twurdi iliact, Linn,

PyRRHULA ALBIFRONS. Pyrr. nigra, capite nuchdque ferrugineo
nitore subtinctis ; fronte maculdque remigum albis.

Longitudo corporis, 73; ale, 4; caude, 3; tarsi, 3; rostri, 3,
altitudo 2.

Proceus cuttuRALis. Ploc. supra pallid? olivaceo-brunneus ;
capite colloque in fronte aurantiacis, corpore subtus aurantiaco-

flavo; gulé juguloque nigris, rostro attenuatiore.

Longitudo corporis, 64.
PLocEus

Roological Society. 233

Proceus sPiLonotus. Ploc. capite supra corporeque subtus au-
rantiacoflavis ; guld, jugulo, dorsoque summo nigris, hoc flavo
maculato ; uropygio fusco-lutescente ; alis caudaque fuscis,

Statura pracedentis ; rostro fortiore.

PLoceus curysoGasteR. Ploc. capite genis corporeque toto supra
saturate castaneo-brunneis; guld flavo et brunneo variegata ; cor-
pore subtus aureo-flavo.

Statura precedentium ; at rostrum mult6 validius.

LAMPROMORPHA* CHALCOPEPLA. Mas, Lamp. supra splendidé
viridis, cupreo nitens ; subtits alba, lateribus viridi-cupreo fascia-
tis ; strigd in capitis medio, secundd superciliart, alteraque maxil-
lari, maculis tectricum alarum, remigum, rectricumque, duabus
mediis exceptis, albis.

Foem. aut mas jun. ? Lamp. corpore supra metallic viridi ; ca ite,
nucha, regioneque interscapulari cupreo splendentibus ; collo in

Sronte pectoreque rufescenti ; abdomine albo, lateribus viridi-eneo

*fasciatis; caudd ferrugined, viridi-eneo Jasciata ; rectricum
trium utringue lateralium pogoniis, omniumque apicibus albo
notatis.

Statura Cuculi aurati, Gmel.

CoryTHAIx PORPHYREOLOPHA. Cor. collo, abdomine medio, pec-
tore, regioneque scapulari gramineo-viridibus, his subrufescenti-
bus ; fronte strigdque per oculos splendidé viridibus ; capite cris-
tato, alis, cauddque splendenti-purpureis ; remigum fascia latd
subpurpurascenti-coccineis ; dorso abdomineque mts, tectricibusque

Jemorum fusco atris ; rostro pedibusque atris,

Statura Cor. Perse, Ml.

Bucco nanus. Bucco supra niger, sulphureo striatus ;_strigd su-
pereiliari gracili, alteraque per totam longitudinem alarum ex-
tendentelatd, aurantiis ; guld crissoque sulphureis, abdomine.fus-
cescenti ; fronte coccineo.

Longitudo corporis, 44; rostri ad frontem, +) ad rictum 53,.

Yunx Pectoratis. Y. supra pallide brunnescenti-griseus, fusco
graciliter undulatus ; nuchd scapularibusque nigro notatis, caudd
nigro fasciatd ; subtis albidus, collo in Sronte confertim, femorum
tectricibus minis confertim, nigro fasciatis, abdomine nigro lie
neato ; maculd grandi pectorali ad gulam extendente rufa ; remi-

__ gibus fuscis, pogoniis externis Serrugineo fasciatis.

Statura Y, Torquille, Linn.

June 28, 1831. Rey. W. Kirby in the Chair,

A letter from Sir Robert Ker Porter, Corr. Memb. Z. S.,
dated City of Caraccas, Venezuela, March 25, 1831, was read. It
announced his having recently obtained possession of a specimen of
the American Lapir, (Tapir Americanus, Gmel.), which it was his

* A group including the shining Cuckoos of Africa, India, and New Hol-
land, indicated in the Transactions of the Linnean Society, vol. xv. p. 300.
Mr. Vigors expressed his belief of having lately seen a name attached to
this group by some modern author ; but he could not call to his recollection
the work in which it occurred.

N.S. Vol. 10. No. 57. Sept. 1831. 2H intention

234 Zoological Society.

intention to transmit to the Society at the earliest opportunity. It
embraced a full description of the animal ; and entered at consider-
able length into an account of its habits. The letter was accompa-
nied by two drawings of the Tapir, and by sketches of its proboscis-
like upper lip. 4

Mr. Gray exhibited the skins and skulls of two Mammalia brought
from China by Mr. Reeves, together with the skull of a third, of
which a skin was also in his possession. On these he proposed to
found three new genera, the characters of which may be given as
follows :

HELIcrIs.

Dentes primores $: laniarit ++: molares 3%; e quibus 3} ante-
riores falsi conici compressi ; carnivori ++, in maxilld superiort
3-lobati, cum processu interno subcentrali lato 2-acuminato ; tu-
berculares 34, superiores mediocres transversi, inferiores exigut.
Caput elongatum. Pedes breves; plante ad calcaneum jferé
nude ; digiti5—5; ungues valide, anteriores longe compress@.
Cauda cylindrica mediocris.

This genus, which inhabits eastern Asia, has the general appear-
ance and colouring of Mydaiis, combined with a dentition resem-
bling that of Gulo or Mustela, but differing from both the latter
genera in the large internal central lobe of the upper carnivorous
tooth. The species exhibited may be characterized in the follow-
ing terms:

HELIicTIs MoscHaTA. Hel. supra argentata, pilis singulis basi
cinereis apice argenteo-albis, so at argenteo a latera corporis et
versus apicem caude dominante, capite pedibusque anticis in

Jusco-cinerascentem vergentibus ; striga inter, aliisque duabus pone,
oculos, macula interauriculari nuchalique, labio superiore, mento,
guld, gastreo medio, femoribusque internis, albis.

The entire length of the animal is 23+ inches, of which the tail
measures 8. It inhabits China, and smells strongly of musk.

Mr. Gray added that the Gulo orientalis of Dr. Horsfield’s ‘ Zoolo-
gical Researches in Java’ appeared to him to form a second species
of the genus, closely resembling the Chinese in its general characters,
and in the disposition of its colouring, but differing in its browner
colour and in the larger proportion of white upon the head and
back. The internal lobe of the upper carnivorous tooth in the Ja-
vanese animal is also described as being anterior and very minute.

PAGUMA.

Dentes primores % equales: laniarii ++: molares % % 3 quorum
utringue in maxilla superiori 3 falsi parvi compressi, 1 carni-
vorus brevis obtusé $-lobus cum processu interno centrali, 2 tuber-
culares subquadrati interné subangustati antice non producti
in maxilla inferiore 4 falsi, 1 carnivorus, 1 tubercularts. Pedes
postici plantigradi, ad calcaneum usque nudi callosi. Caudatonga
attenuata.

In the number and disposition of its teeth this genus agrees with
Viverra, from which, however, it differs in their conformation. It
is much like Ictides in colouring, but has about the face the pale

marking

Intelligence and Miscellaneous Articles. 235

marking of Paradorurus; the skin has the odour of civet. From
the genus Viverra it is distinguished by the shape of its skull, the
cerebral cavity being in it much larger, the space between the eyes
broader, and the nose much broader and shorter. The species was
characterized in the following terms :
PacuMa LARvATA, Pag.grisea ; fascié alba frontalitransversa,
alteraque longitudinal per frontem ad nasum ductd; caudé
apice nigrescentt.
Gulo larvatus. Ham. Smith in Griff. Transl. Cuv. Régn. An. ii.
p. 281, c. fig.

Viverra larvata. Gray, Spic. Zool. p. 9.

The third genus described was founded on a glirine quadruped,
nearly allied to the Bamboo-Rat (Mus Sumatrensis, Raffl.?), with
which Mr, Gray associated it under the following characters.

/RHIZOMYS.

Dentes primores 3% maximi, elongati, triangulares, acutati: mo-
lares 3 3 radicati, subcylindrici, coronis transversim subparal-
lelim porcatis ; superiores interne lobati, Caput magnum. Ocult
parvi apertt. Auricule nude conspicue. Corpus crassum sub-
cylindricum. Pedes breves validi, digitis 5—5. Cauda mediocris,
crassa, nuda.

In teeth and general appearance this genus is most nearly allied
to Spalax, from which it differs in its tail of moderate length, its
exposed eyes and ears, and the more complex character of its
molar teeth. The species of Rhizomys live moreover upon, and
not under, the ground, being found about Bamboo-hedges, on the
roots of which they principally subsist. The following were stated
to be the distinctive characters of the two species known.

Ruizomys Sivensis. Rhiz. pallidé cinerascens unicolor.

Hab. in China. D. Reeves.

Ruizomys Sumarrensis. Pallidé fuscus, pilis raris albidis in-
terspersis ; corporis lateribus pedibusque saturatioribus ; genis
pallidioribus, occipite nigrescenti lined longitudinali alba, pec-
tore albido.

Mus Sumatrensis, Raffles, Linn. Trans. xiii. 258? Temminck,
Mus. Leyd.

Spalax Javanus, Cuv. Hage Anim., ed, 2., i. 211.

Hab. in Sumatra, Raffles? Temminck; Java, Cuvier.

The latter species seems to have been first observed by Colonel
Farquhar, in whose collection of drawings, preserved in the Museum
of the Asiatic Society, a representation of it is found. Of the former
we owe the discovery to Mr. Reeves.

XXXI. Intelligence and Miscellaneous Articles.
PREPARATION OF IODIC ACID. BY ARTHUR CONNELL, A.M.

HE methods which have been hitherto followed for the formation

of iodic acid, may be reduced, Mr. Connell remarks, to three :
Jirst, the action of alkaline solutions, giving rise to the formation of
a 2 > a hydrio-

236 Intelligence and Miscellaneous Articles.

a hydriodate and an iodate, from the latter of which the iodic acid
may be separated by the original method of M. Gay-Lussac, and
more perfectly by the recent method of M. Serullas (Ann. de Chim.
et de Phys. xliii. pp. 127 and 217); secondly, the action of euchlo-
rine, as suggested by Sir H. Davy; and, thirdly, the action of water
on the perchloride of iodine, and subsequent separation of iodic
acid by means of alcohol, as also proposed by M. Serullas (see Phil.
Mag. and Annals, N.S, vol. ix, p- 149): to these Mr, Connell pro-
poses to add the agency of nitrie acid, which he thinks will be found
to equal in facility of execution any of the preceding processes.

The vessel employed was a rather large and tall flask, into which
fifty grains of iodine and an ounce of fuming nitric acid were put;
the acid was made to boil, and as soon as any iodine sublimed and
condensed on the sides of the vessel, it was washed back again into
the liquid by agitation. After the process had been continued
some time, a precipitation of white crystalline grains was observed
to take place; and the operation of boiling and washing back the
sublimed iodine was continued until the free iodine had to a great
extent disappeared. The whole was then decanted into a shallow
basin and evaporated to dryness. Any free iodine which had re-
mained was soon dissipated by the heat. The residue of the eva-
poration consisted of whitish crystalline grains, which were iodic
acid, retaining a little nitric acid, from which they appeared to be
freed by one or two solutions in water, and re-evaporations, when
they lost most of their crystalline appearance, and became a whitish
deliquescent mass, occasionally with a light purplish tint, from a
tendency to decomposition by the heat of evaporation. Where no
particular precautions were taken to prevent loss in the state of
vapour, and where the process was not continued until the entire
disappearance of iodine, the quantity of acid obtained approached
that of the iodine employed; a larger proportion of iodine might
probably be used, with the same quantity of acid. — Jameson’s
Journal, June 1831, p. 72.

. NEW SCIENTIFIC BOOKS.
Just published.

The Twenty-second Number of Professor Leybourn’s Mathema-
tical Repository is published. It contains solutions to twenty
questions in different parts.of pure and mixed mathematics (and as
many new ones for future solution) by various contributors.

The separate papers are: 1. Two indeterminate Problems, by
James Cunliffe, Esq. late of the Roy. Mil. Coll. 2. Analysis and
Construction of a Geometrical Problem, by C. F. Barnwell, Esq.,
A.M, F.R.S. F.S.A. 3. A History of the Investigations respecting
the Properties of Rule Surfaces, or such as can be generated by
the motion of a right line subjected to certain conditions, by T. 8.
Davies, Esq. F.R.S.E, F.R.A.S. 4. An Inquiry into the Author
of the Second and Third Properties of the Stereographic Projection
of the Sphere, completing the Inquiries of Delambre on that Sub-
ject in his History of Astronomy, by the same Gentleman. 5. Hore

Arithmetice,

Intelligence and Miscellaneous Articles. 237

Arithmetice (No. 8.); or Historic Memoranda respecting circum-
stances connected with his new method of Continuous Approxi-
mation to the Roots of Numerical Equations, by W. G. Horner,
Esq. 6. Analytical Investigation of the Curious Property of Lines
of the second order which formed the Prize Question of this num-
ber (geometrical demonstrations of which had been given in their
proper place by Messrs. Davies and Woolhouse), by T.S. Davies,
Esq. F.R.S.E. &c. 7. Researches in the Geometry of Three Di-
mensions (incomplete), by the same Gentleman. 8. Pascal’s first
work, being on Conics, together with an account of other papers of
his on the same subject, by Leibnitz. 9. Solutions of the Sixty
Problems in the Rev. John Lawson’s Geometrical Analysis of the
Ancients, by the Rev. Charles Wildhore.

The Number also contains lists of the mathematical papers pub-
lished in the Transactions of different learned Societies; and of the
Questions proposed in the Cambridge Senate House on examination
for degree of A.B, and for Smith’s prizes.

MR. SAULL’S GEOLOGICAL MUSEUM.

W. D. Saull, F.G.S. &c. has recently become the possessor of
the extensive Geological Museum of the late Mr. Sowerby, of Mead
Place, Lambeth, the whole of which is now stratigraphically arranged,
with the addition of Mr. Sauil’s previous collection of fossils, and will
be open for the inspection of scientific gentlemen, and _ friends,
every Thursday morning, at his residence No. 15, Aldersgate-street,
City.

LUNAR OCCULTATIONS FOR SEPTEMBER.

Occultations of Planets and fixed Stars by the Moon, in September
1831. Computed for Greenwich, by THomas HENDERSON, Esq. ;
and circulated by the Astronomical Society.

Immersions. Emersions.

Cat.

Angle from

Sidereal | Mean .; |Sidereal| Mean | ~
time. solartime.| 5 ¢ time. |solartime.) ©
(2)
D Az

Stars’
1831.| Names,

Magnitude.
Ast. Soc.
No

reel ae aT iy cena i) Tia 5 AD i v7

h
Sept.11| y Libre... | 4-5 |1764| 20
19| 58 Aquarii| 6 |2690\ 2
20) x% Aquarii | 5°6 |2776| 22
22) 33 Ceti..... 6 125) 3
30} o* Cancri...| 6 |1094| 4

7 **
7| 14 34 | 141)174!) 3 22) 15 29 | 263
3) 10 7 |122) 110/23 17} 11 21 | 288
5
tf

15 011380] 152| 4 10] 16 5 | 278
15 30 | 69} 29) 5 11) 16 34 | 275

METEORO-

238 Meteorological Observations for July 1831.

METEOROLOGICAL OBSERVATIONS FOR JULY 1831.
Gosport :—Numerical Results for the Month.

Barom. Max. 30-348. July 6. Wind N.E.—Min. 29-606. July 13. WindS.E.
Range of the mercury 0-742.

Mean barometrical pressure for the Month .......s.ceceseseseeseseeee 29999
Spaces described by the rising and falling of the mercury............ 3190
Greatest variation in 24 hours 0-259.—Number of changes 15,

Therm. Max. 79°. July 9. Wind W.—Min. 52°. July 3. Wind W.

Range 27°.—Mean temp. of exter. air 64°°68. For 31 days with © in 63°40
Max. var. in 24 hours 22°-00.— Mean temp. of spring-water at 8 A.M. 51-81

De Luc’s Whalebone Hygrometer.
Greatest humidity of the atmosphere, in the evening of the 23rd.... 100°
Greatest dryness of the atmosphere, in the afternoon of the 9th ... 43-0

Range Gh MG IHIeR a ifenecarsnansnsnecusssipeacnQurpnsebaagetnecnscasnesdenccue 57-0
Mean at 2 P.M. 55°-2,—Mean at 8 A.M. 61°4.— Mean at 8 P.M. 67:5

of three observations each day at 8, 2, and 8 o’clock......... 61:4
Evaporation for the month 4-55 inches.
Rain in the pluviameter near the ground 3-465 inch.
Prevailing winds, West.

Summary of the Weather.
A clear sky, 43; fine, with various modifications of clouds, 153; an over-
cast sky without rain, 73; rain, 33.—Total 31 days,

Clouds.

Cirrus. Cirrocumulus. Cirrostratus. Stratus. Cumulus. Cumulostr. Nimbus.
23 16 Q7 3 28 23 16
Scale of the prevailing Winds.

N. N.E. Be SE Sst SW We Nee Days.
2 4 TOG li 6 8 Qh 31

General Observations.—This month has been fine, with the exception of
four or five days, when much rain fell here. In the evening of the 5th,
Venus was in conjunction with x Leonis, and they formed a small isosceles
triangle with Saturn. At midnight of the 8th several flashes of lightning
ascended from the horizon in the north-east quarter. The 9th was the
hottest day in the shade, and there were a few flashes of lightning in the
night in the south-east horizon. Sheet lightning also occurred the fol-
lowing evening. Much rain fell on the 11th, 12th, and 14th, which was
accompanied with lightning and thunder. Distant thunder and lightning
also occurred in the afternoons of the 16th and 28th. In the afternoon of
the latter day the edge of a thunder-storm passed this place, and proceeded
with some violence in its electrical effects in the direction of Berkshire.
Not only in Hampshire, but in most other counties, thunder-storms have
often occurred through the month, so that the period may be said to have
been a war of the elements.

On the 19th, 20th, 21st, and 22nd, a hard gale blew from the South-
west, and on the following day it blew equally hard from the opposite
point of the compass, with a copious rain, and a considerable decrease in
the temperature of the air.

The rain and wind lodged some of the corn in this neighbourhood.

From the 25th to the end of the month the weather was dry and warm,
and on several days a thermometer in the sun’s rays rose to 120 degrees,
which had the effect of ripening the wheat, and harvest commenced here
at the close with every prospect of good average crops.

Soon after ten o’clock in the night of the 30th, an aurora borealis ap-
peared, whose upper arch, though not well defined, was about 16 i

1B

ae

Meteorological Observations yor July 1831. 239

high in the magnetic north ; but the lower arch was low, and could not be
traced in consequence of a dark vaporous herizontal cloud before it. At
a quarter past ten several bright yellow columns, 20° in altitude, rese
from the aurora under Polaris, when one brilliant meteor descended be-
tween that star and Dubhe in Ursa Major. Coruscations continued to
rise between the true and magnetic north till a quarter to eleven, when the
moon was several degrees above the horizon, and the aurora disappearing.
It was lately mentioned at Portsmouth by a public lecturer on aérology,
that Jupiter’s attraction of the atmosphere of the earth is greater than
has been generally supposed ; and that when the moon is near him, he has
so powerful an attraction over our atmosphere, as to disturb its elasticity
and draw it up considerably out of its spheroidal form, by which means
electrical action and a condensation are produced, so as to cause heavy rain ;
and that the effect is greater when Jupiter crosses the northern part of
the Pacific Ocean in his north declination, and the South Sea and Atlantic
Ocean in his south declination, in consequence of the abundance of va-
pours arising from them. This opinion (conceived to be new by the
lecturer), although not new to men of scientific pursuits, certainly deserves
the strictest investigation in a meteorological point of view, it having been
verified in almost all the lunations this year, even in this latitude, when
the moon has been near Jupiter; and as this planet is 1312 times larger
than the earth, it is not surprising if we admit the principle of attraction
of the heavenly bodies, that he should conjointly with the moon exert so
great an influence over our atmosphere.

‘The mean temperature of the external air this month is nearly half a
degree higher than the mean of July for many years past.

The atmospheric and meteoric phenomena that have come within our
observations this month, are, two solar halos; one meteor; one aurora
borealis ; lightning on eight days and thunder on four, and five gales of
wind, namely, one from the North-east, three from the South-west, and
one from the West.

REMARKS.

London.—July 1,2. Fine. 8. Slight rain: fine. 4:Very fine. 5. Fine:
slight rain at night. 6—9. Very hot. . 10. Thunder at noon, with slight
rain: very heavy storm to the eastward, 11. Hout. 12. Heavy showers.
13. Rain in the morning: fine. 14. Cloudy: rain at night. 15. Rain,
with some thunder in the afternoon. 16. Cloudy, with thunder showers.
17—19. Fine. 20. Cloudy and windy, with slight rain. 21. Fine.
22. Fine, with slight showers. 23. Fine: rain atnight. 24—27. Very
fine and warm. 28. Sultry: thunder, with rain towards night. 29, Very
hot: thunder in the afternoon. 30, 31. Very fine.

Penzance.—July 1.Fair, 2. Fair: rain. 3. Fair. 4. Misty: fair. 5. Rain:
fair. 6.Clear. 7.Fair: clear. 8.Clear. 9,10. Fair. 11. Fair: rain.
12. Fair: thunder-shower. 13. Showers. 14. Fair: showers. 15. Fair:
rain. 16. Fair: shower. 17. Fair. 18.Showers: fair; 19. Misty: rain.
20. Rain: showers. 21,22.Showers. 23. Heavy rain. 24—27. Clear.
28. Fair. 29—31. Clear.

Boston. — July 1, 2. Fine. 3. Cloudy. 4, Fine: Therm. 74° 3 p.m.
5.Cloudy: raina.m. 6.Cloudy. 7,8.Fine. 9. Fine: Therm, 78°5, 1 p.m.
10. Cloudy: rain p.m. 11. Cloudy. 12. Fine. 13. Cloudy: rain a.m.
ande.m. 14. Fine: rain, with heavy thunder-storm 1 p.m. 15,16. Rain.
17—19. Fine. 20.Cloudy. 21. Cloudy: rain early a.m. 22. Stermy.
23—25.Fine. 26.Cloudy. 27.Fine: Therm. 74° 4p.M, 28. Cloudy.
29. Fine: Therm. 80° 1 x.m. 30. Cloudy: rain early a.m. $1. Fine.

Meteoro-

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THE

PHILOSOPHICAL MAGAZINE

AND

ANNALS OF PHILOSOPHY.

—=>——_

[NEW SERIES.]

OCTOBER (1831.

XXXII. Researches on some of the Revolutions which have
taken place on the Surface of the Globe; presenting various
Examples of the Coincidence between the Elevation of Beds in
certain Systems of Mountains, and the sudden Changes which
have produced the Lines of Demarcation observable in certain

Stages of the Sedimentary Deposits. By L. Exe pe Brav-
MONT*.

Two great views, one a succession of violent revolutions,

the other the elevation of mountain-chains by forces act-
ing from beneath, having been successively introduced into
geology, it was natural to inquire if they were independent
of each other; if mountain-chains could be raised without
producing real revolutions on the surface of the globe; if the
frightful convulsions which must have accompanied the up-
burst of masses so great and of an aspect so contorted as
those of high mountains, were not the same with those revo-
lutions on the surface of the globe which are proved to have
taken place by the mineralogical and zoological lines of de-
marcation observable in the sedimentary deposits.

The principal object of the researches, of which the follow-
ing is a brief sketch, is to show, term for term, the connection
of these two series of facts.

It will be necessary to premise a few words respecting the
principles on which these researches have been conducted.
The expression sedimentary deposits (terrains de sediment) in
which we, in some measure, sum up our knowledge of those
masses so widely spread over the surface of our planet, so

* Extract forwarded to Mr. De la Beche in May 1831, and communi-
cated by the latter to the Editors.

N.S. Vol. 10. No. 58. Oct, 1831. 9 | naturally

D2 Elie de Beaumont’s Researches on some of

naturally carries with it the idea of horzzontality, that it is never
without surprise we first hear of sedimentary beds observed
in a vertical or nearly vertical position.

As early as 1667, Stenon maintained that all inclined sedi-
mentary beds were upraised; and since the observations of
De Saussure on the Valorsine conglomerates, geologists have
generally agreed in considering those sedimentary beds which
are frequently observed in mountainous countries either in-
clined at considerable angles, placed vertically, or even thrown
over, as not having been formed in that position, but as having
been so circumstanced, in consequence of phenomena which
have taken place at a greater or less time after their original
deposition.

There are few countries where these phzenomena have been
produced at so late a period, as to affect all the sedimentary
deposits there existing, even abstracting the alluvion of modern
rivers, which in all cases has not yet been disturbed by any
phznomena of this nature.

We observe along nearly all mountain chains, when we at-
tentively examine them, that the most recent rocks extend
horizontally up to the foot of such chains, as we should expect
would be the case if they were deposited in seas or lakes of
which these mountains have partly formed the shores; whilst
the other sedimentary beds tilted up, and more or less con-
torted on the flanks of the mountains, rise in certain points
even to their highest crests. Thus in each chain, or rather
in each system of chains, the series of the sedimentary rocks
is divided into two distinct classes, and the point of separation
of these two classes, variable from one system to another, is
one of the circumstances which best characterizes each parti-
cular system.

At the same time that the position of the ancient and in-
clined beds furnishes the best proof of the elevation of the
mountains of which they constitute a part, the geological age
of these beds affords the best means of determining the rela-
tive age of the mountains themselves; for it is evident, the
first appearance of the chain itself is necessarily intermediate
between the period when the beds, now upraised, were depo-
sited, and that when the strata were produced horizontally at
its feet.

There is nothing so essential to remark, as the constant
clear line of separation between these two series of beds in
each chain. This kind of observation is sanctioned by long
experience. Geologists have, in fact, been long accustomed to
employ the absence of parallelism in the stratification of two
systems of beds, the one supporting the other, as ANDROS

j the

the Revolutions which have taken place on the Globe. 243

the clearest line of demarcation that can be found between
two systems of consecutive sedimentary deposits. This idea,
which has been developed in the lessons: of the most distin-
guished professors, has, it may be said, become common. It
was indeed on a fact of this nature, generalized certainly be-
yond measure, that Werner founded his principal division in
the series of rocks. Now it follows from this difference,
always clear and without passage, between the upheaved beds
and those which are horizontal, that the elevation of the beds
has not been effected in a continuous and progressive manner,
but that it has been produced in a space of time comprised
between the periods of deposition of the two consecutive rocks,
and during which no regular series of beds was produced ;—
in a word, that it was sudden, and of short duration.

It has been in vain attempted to explain the geological facts
observable in high mountain-chains, by the action of the slow
and continuous causes now in force on the surface of the globe.
No satisfactory result has been obtained by these means. In
fact, everything shows that the instantaneous elevation of the
beds of a whole mountain-chain is an event of a different order
from those which we daily witness. It is evident that such a
convulsion would interrupt the slow and progressive forma-
tion of the sedimentary deposits, and that some anomalous
circumstance would be nearly universally observable in that
point of the series of rocks which should correspond with the
moment when an elevation of beds took place. It is well
known that those geologists who have most carefully exa-
mined the sedimentary deposits, and those naturalists who
have investigated the remains of animals and vegetables which
they contain, have generally remarked that between different
terms of the series of these rocks there are sudden variations,
not only in the position and local character of the beds, but
also in the fossil animals and vegetables entombed in them.
From observations which did not comprise a sufficiently ex-
tensive area, some of these variations (to lessen the value of
which too many attempts have perhaps been subsequently
made) were at first supposed more general than they really
are. When two formations appear to pass insensibly into
each other, there is never more than a small depth of beds
of which the classification may remain uncertain; and when
certain fossils are common to two successive formations, they
generally constitute a fraction, often even inconsiderable, of
the total number of species found in each of the two forma-
tions. ‘This is more particularly seen in the comparison in-
stituted by M. Deshayes (in a work impatiently expected by
geologists) between the catalogues of the species of shells

212 discovered

244 Elie de Beaumont’s Researches on some of

discovered in the three groups, which he distinguishes in the
beds above the chalk, and the catalogue of species now ex-
isting. It is sufficient, that in the series of superimposed beds
there are points more remarkable than ,others, on account of
the changes they exhibit, both in the deposits and in the in-
habitants of the same country, to be struck with the accordance
of the two orders of considerations above noticed.

Among those observations which render it impossible to
consider the dislocation of beds which characterizes a moun-
tainous country as the result of local phenomena, which may
have been repeated in an irregular and successive manner,
we may place in the first rank the constancy of the direction
in which sedimentary beds are tilted up even for immense
distances.

Practice has taught miners from time immemorial the prin-
ciple of constancy in directions, and it is one of those circum-
stances which they most usefully employ in their researches.
The observation of constancy in the direction of beds in the
coal-measures, has served to discover a bed of coal at a di-
stance, though invisible on the surface. It was by combining
the observations made in numerous metallic mines, that Wer-
ner arrived at the conclusion, that, in the same district, all
the veins of the same nature were due to cracks parallel to
each other, formed at the same time, and subsequently filled
at the same period. The remarkable phenomenon of con-
stancy of direction has been gradually shown to be more im-
portant, by the labours of those geologists who since De
Saussure and Pallas have attentively examined mountain
chains. It has been admitted by degrees, that the circum-
stance which best characterizes mountain-chains, when com-
pared with each other, is the direction which the elevation
of the beds has impressed upon them,—a direction naturally
observable in the crests composed of such beds. For more
than thirty years M. Humboldt has pointed out the equally
remarkable accordances and discrepancies observable in the
direction of mountain-chains, whether close to, or remote from,
each other. M. von Buch has also shown that the mountains
of Germany are divisible into at least four systems, clearly
distinguishable from each other by their directions. So clear
a mode of distinction even led him to conceive that the various
mountain systems were produced by phzenomena independent
of each other; and it is at the same time very probable, that
not only, as is proved by observation, all beds upheaved at the
same time have been so raised in the same direction, but also
that this constancy in the direction of the upraised beds in a
certain assemblage of mountains, is the result of this ia

ts)

the Rewolutions which have taken place on the Globe. 245

of beds having been thrown up at the same time by a single
effort of nature: whence it would follow that the number of
the epochs of elevation would not be unlimited, but that it
would at least be equal to that of the directions of those chains
which are clearly distinct,-—a number not incompatible with
that of the solutions of continuity observable in the sedimen-
tary deposits.

it became necessary, in order to carry the subject beyond
these vague and general views, that a comparison should be
instituted between the number of those lines of demarcation
observable in the sedimentary deposits, and the same number
of mountain systems. It has been attempted to accomplish
this by combining the two great principles above noticed ;
namely, that the highly inclmed sedimentary beds are up-
heaved strata, and that in each mountainous district all the
beds upheaved at the same moment have been so raised in the
same general direction.

The examination of the surface of Europe has in this man-
ner already led to the determination, both with respect to age
and direction, of the twelve systems of mountains to be suc-
cessively noticed in the sequel, as also their relation to twelve
solutions of continuity observed in the series of sedimentary
deposits.

I. System of Westmoreland and of the Hundsruck.—:The cor-
respondence of this nature which may be referred to the most
ancient geological epoch has been made known by the re-
searches of Professor Sedgwick, recently communicated to the
Geological Society of London. ‘The mean line of bearing of
the different systems of slate rocks in the lake mountains of
Westmoreland, is shown by this author to be nearly N.E. by
E., and S.W. by W. This causes them to abut successively
against the carboniferous zone; from which it follows that
they must also be unconformable to it. Professor Sedgwick
strengthens this inference by reference to detailed sections :
and from the whole of the evidence he concludes, that the
central lake mountains were placed in their present position,
not by along continued, but by a sudden movement of eleva-
tion, before or during the period of the old red sandstone*.

Professor Sedgwick has also shown that if lines be drawn
in the principal bearing of the following chains,—viz. the
southern chain of Scotland, from St. Abbs Head to the Mull
of Galloway; the grauwacké chain of the Isle of Man; the
slate ranges of the isle of Anglesea; the principal grauwacké

* From other circumstances to be noticed in the sequel, it appears very
probable that this movement of elevation was anterior to the deposition
of the most recent strata of the transition series.

chains

246 Elie de Beaumont’s Researches on some of

chains of Wales, and the Cornish chain,—they will be nearly
parallel to each other and to the line of bearing of the lake
mountains. The elevation of these chains, which produce
marked effects on the physical character of Great Britain, is
referred by Professor Sedgwick to the same period; and the
parallelism is not considered accidental, but as offering a con-
firmation of the general principle,—that mountain-chains, all
elevated at the same period of time, present a general paral-
lelism in the bearing of their component strata.

The surface of continental Europe presents many moun~
tainous countries, in which the predominant direction of the
most ancient and disturbed beds is, as has been remarked for
more than thirty years by M. Humboldt, but slightly re-
moved from a N.E. and S.W. line. Such is, for example, the
direction of the grauwacké and slate beds in the mountains of
the Eiffel, the Hundsruck, and of Nassau, at the feet of which
were probably deposited the coal-measures of Belgium and
Saarbruck. Such is also the direction of the slate, grauwacké,
and transition limestone beds of the northern and central parts
of the Vosges, on the edges of which there are several small
coal basins.

The parallelism of this direction to that observed by Pro-
fessor Sedgwick in England, added to the fact, thatin the Vosges
this direction of the slate and grauwacké strata is not carried
into the coal-measures, leads us naturally to suppose that the
inclined position of these parallel beds of England and the
Continent is due to the same catastrophe, the most ancient of
any of which traces can at present be clearly recognised.

Further researches may perhaps show the relation that
may exist between the different parts of the Westmoreland
slate rocks, and more effaced and older elevations of strata
than this now under consideration.

II. System of the Ballons (Vosges) and of the Hills of the Bocage
(Calvados).—The observations noticed in the preceding article,
only prove that the system of Westmoreland and the Hunds-
ruck have been elevated before the deposition of the carboni-
ferous series; but it would appear that it had been elevated
even before the deposit of the more recent transition rocks.
In fact, among those beds which we are in the habit of com-
prising in the general denomination of transition rocks, there
is a widely extended class which has not been affected by the
N.E. and S.W. elevation of the ancient slates, and which
may have been deposited on these beds, previously upheaved.
Such are the marly and arenaceous limestones with Ortho-
ceratites, Trilobites, Hysterolites, &c. which occur in Podolia,
in the environs of St. Petersburg, in Sweden, and in Norv:

where

the Revolutions which have taken place on the Globe. 247

where they are in general but slightly removed from their
original horizontal position. Such are also the transition rocks,
so rich in organic remains, of Dudley and Gloucestershire,
which appear to have been deposited at the foot of the pre-
viously elevated mountains of Wales, and which are them-
selves only affected by dislocations of a more recent date.

Such would also appear to be a part of the transition beds
of Southern Ireland, known by the recent researches of Mr.
Weaver. This distinguished geologist remarks that some
parts of the system resemble, both in mineralogical and zoo-
logical characters, the rocks of Tortworth in Gloucestershire.
The principal rock masses in the South of Ireland are com-
posed of grauwacké, quartz rock, and limestone; they con-
tain crinoidal remains, Trilobites, Orthoceratites, Ellipsolites,
Ammonites, Euomphalites, Turbinites, Neritites, Melanites, and
several species of Terebratula, Spirifer, Producta, and other
bivalves, Hysterolites, and many genera of Polyparia. The
anthracite and accompanying pyritiferous strata are charged
with the remains or impressions of plants, belonging chiefly
to the genera Equisetum and Calamites, with traces of Fu-
coides.

The transition rocks of the Bocage (Calvados) and the in-
terior of Britanny bear a great resemblance to those described
by Mr. Weaver in the South of Ireland. They are like them
composed of numerous beds of slate, grauwacké, quartz rock,
and limestone, containing fossils of the same class, and pre-
senting mines of anthracite.

Finally, I am induced to refer to the same epoch the slate
and grauwacké rocks with anthracite (worked for profitable
purposes, and which contain vegetable impressions differing
but little from those discovered in the coal-measures), which
form the S.E. angle of the Vosges, and which appear to rest
against the granitic masses of the environs of Gerarmer, Re-
miremont, and Tillot; masses which probably were themselves
raised at the formation of the old N.E. and S.W. lines of
elevated strata. Independently of the geological relations
which are apparent between the different parts of the vast
deposit of transition rocks above noticed, they have also in
common remained unaffected by the ancient N.E. and S.W.
system.

When these beds are not horizontal, they are dislocated
in directions the most marked of which, probably produced
immediately after their deposit, is comprised between an
FE. and W. line and one E. 15° S. and W. 15° N. Thus
the masses of granite and porphyry which, in the S.E. part

of

248 Elie de Beaumont’s Researches on some of

of the Vosges, constitute the summits of the Ballon d’ Alsace
and the Ballon de Comté, range from E. 10° or 15° S. to W.
10° or 15° N., and have thrown up the anthracitic rocks in
this direction. ‘The coal-measures of Ronchamps are deposited
at the foot of these mountains on the edges of the upheaved
beds. The Ballon d’ Alsace rises 2586 English feet above the
town of Giromagny, built on a level with the coal-measures ;
and the Ballon de Gebweiler, situated more to the N.E., rises
3067 English feet above the same point. Among those in-
equalities on the surface of the globe, the date of which we
can with probability refer to so remote an epoch, we cannot
cite any more considerable.

The transition beds of Britanny and of the Bocage of Nor-
mandy, on which the coal-measures of Littry and Plessis
are deposited, run in a direction comprised within the above-
mentioned limits, as is also the case with the transition beds
of Ireland, so ably described by Mr. Weaver. The South of
Ireland is a hilly and diversified region, composed of ridges
having generally an east and west direction, and attaining
their greatest elevation in the mountains of Kerry, where Gur-
rane ‘I'val, one of Magillycuddy’s Reeks, near Killarney, rises
3410 feet above the sea. The transition rocks of the same
region have a general direction from east to west, and dip
to the north and south with vertical beds in the axes of the
ridges. The strata, as they diminish in inclination, on each
side form a succession of troughs, the beds dipping rapidly to
the north or south, and bending to horizontality between the
ridges.

These rocks decline gradually towards the north, and finally
pass beneath the unconformable deposits of the old red sand-
stone and carboniferous limestone of the midland counties; a
discordance rendered particularly striking by the horizontal
position of the carboniferous limestone of some districts.

In Devonshire and Somersetshire the grauwacké and slates,
sometimes containing small seams of carbonaceous matter, also
present a nearly east and west direction, and are seen clearly
to have been upheaved previous to the deposition of the Exeter
red conglomerate or todte liegende, because the latter covers
the edges of the former, as may be seen in many situations.

The grauwacké chain of Magdeburg has also a direction
comprised within the above-noticed limits; and according to
the observations of Professor Sedgwick and Mr. Murchison,
it contains the abundant impressions of true coal plants. This
same direction is again observed in the older rocks of the
Hartz, where we are certain that the dislocations were in part

effected

the Revolutions which have taken place on the Globe. 249

effected prior to the deposition of the secondary beds which
extend at the foot of the mountains; and particularly before
the formation of the coal-measures of Ilefeld.

This system, joined to that previously noticed, and perhaps
also to others which have not yet been studied, has produced
an undulated surface and a dislocated structure in the ancient
land (ur und uebergangsgebirge), in the inequalities of which
the first beds of that mass of rocks was deposited which
Werner named fletz gebirge, and the English and French
geologists secondary deposits, deposits of which the carboni-
ferous series (old red sandstone, mountain limestone, and coal-
measures) constitutes the lowest part.

III. System of the North of England.—From the latitude of
Derby to the frontiers of Scotland, the surface of England is
divided by a mountainous axis, which, taken as a whole, runs
nearly from south to north, stretching a little towards the
N.N.W. In that chain which, being wholly formed of beds
of the carboniferous series, is called the great carboniferous
chain of the North of England, the forces of elevation appear
on the whole to have acted (though not without considerable
deviations) on a line bearing nearly north and south (inclining
but a few degrees to the N.N.W. and S.S.E.). Hence great
faults have originated, by one of which its western limit is
tracked through the Peak of Derbyshire. This is prolonged
through an anticlinal line into the high western moors of
Yorkshire, and there the western escarpment of the chain is
accompanied by enormous breaks from the heart of Craven
to the foot of Stainmoor. Another enormous break, passing
under the escarpment of the Cross-fell range, meets the pro-
longed line of the Craven fault at an obtuse angle near the
foot of Stainmoor. By this last fault the insulated position of
the lake mountains is at once explained.

In Professor Sedgwick’s memoir, whence the above is de-
rived, we find direct proofs that all the fractures above men-
tioned took place immediately before the formation of the
conglomerates of the new red sandstone (rothe todte liegende),
and he affords the strongest reasons for believing that they
were produced by an action both violent and of short duration ;
for we pass at once from the inclined and disrupted masses to
the horizontal conglomerates now resting upon them; and
there is no trace of any effect that indicates a slow progress
from one system of things to the other. Lastly, Professor
Sedgwick, speculating on the origin of the phenomena de-
scribed, points to the different crystalline rocks which appear
near the carboniferous chain (toadstone of Derbyshire, and
whinstone of Cumberland).

N. S. Vol. 10. No. 58. Oct. 1831. 2K The

250 Elie de Beaumont’s Researches on some of

The elevation of the chain of the North of England has
very probably not been an isolated phenomenon. If we glance
at the geological map of England by Mr. Greenough, and
that which accompanies the memoir of Dr. Buckland and
Mr. Conybeare on the environs of Bristol, we are naturally
led to remark that the problematical rocks which pierce and
dislocate the coal deposits of Shrewsbury and Colebrooke
Dale, and those which constitute the Malvern Hills, appear
connected with a series of fractures which run nearly north
and south, being prolonged across the recent transition beds
and the carboniferous rocks to the environs of Bristol.

The coast, with a north and south direction, which bounds
the western part of the department of La Manche, may pro-
bably also be due to a fracture of the same class as those of
the great carboniferous chain of the North of England.

IV. System of the Pays Bas and of South Wales.—From the
environs of Aix-la-Chapelle to the small isles of St. Bride’s
Bay, Pembrokeshire, over a length of about four hundred
English miles, the different portions of the carboniferous series,
wherever they are not concealed from observation by more
recent formations, are seen in a greater or less state of com-
plete dislocation. ‘There are situations, as at Liége, Mons,
Valenciennes, the Boulognais, and the Mendip Hills, where
they have suffered very considerable contortions and disloca-
tions. Throughout a large portion of this extent, these beds,
which in no part rise to great heights, are covered by more
recent deposits, resting horizontally on their edges. ‘The vast
sheet of recent deposits which covers the carboniferous series
between the environs of Boulogne and those of Bristol, might
even throw doubt on the mutual connection of the dislocations
in the Pays Bas and the coasts of the Bristol Channel: it is
nevertheless certain that the dislocations in both situations
possess common characters; such as not widely differing from
an east and west direction, without however preserving the
same line of bearing for great glistances, and only producing
small protuberances on the surface of the land, notwithstand-
ing the contortions of the beds in the interior.

In the environs of Liége and Aix-la-Chapelle, the direction
of the carboniferous beds becomes nearly parallel to that of
the argillaceous slates and grauwacké of the Eiffel and the
Hundsruck; but it is probable that this arises from the frac-
tures of the carboniferous series having been inflected in such
a manner as to follow the ancient dislocations of the pre-
existing rocks; for it would be difficult not to admit, from the
facts previously noticed, that the elevation of the slate and grau-
wacké of the Eiffel and the Hundsruck, following a direction

nearly

the Revolutions which have taken place on the Globe. 251

nearly N.E. and S.W., was not referrible, like that of the
analogous rocks in Westmoreland, to a much more remote
epoch.

The dislocation of the coal-measures of Saarbruck is also
probably referrible to the same epoch as that of Glamorgan-
shire and the Pays Bas, as it offers nearly the same direction
and characters.

In the environs of Bristol the magnesian conglomerate
horizontally covers the edges of the dislocated carboniferous
beds, and the grés de Vosges is seen at Saarbruck in the same
position. The elevation of the beds now under consideration
ought therefore to be anterior to the deposition of the mag-
nesian conglomerate of Bristol and of the grés de Vosges;
but as the todte-liegendes (grés rouge), properly so called,
does not on any point rest on the carboniferous beds elevated
in the direction in question, we may be permitted to presume
that their elevation took place after the deposit of the todte-
liegendes.

V.. System of the Rhine. — The Vosges and the Swartzwald
form two groups of mountains, to a certain extent symmetrical,
terminating one opposite the other in two long cliffs, the ge-
neral directions of which are parallel to each other, and to
the course of the Rhine which flows between them from Bale
to Mayence. These two cliffs, between which extends the great
valley of Alsace, are the most clearly defined characters of
that assemblage of mountains which M. von Buch has grouped
together under the name of the system of the Rhine. They
are partly formed by beds of the grés de Vosges, and appear
due to great fractures or faults, with a direction nearly S. 15°
W., and N. 15° E., which have broken them after their depo-
sition. The epoch of this disturbance has necessarily preceded
that of the deposition of all those beds which extend from one
cliff to the other, forming the slightly undulating base of the
basin of Alsace, and among which occur the red or variegated
sandstone (grés bigarré), the muschelkalk, and the variegated
marls (marnes irisées). The last three formations have ex-
tended round the mountains constituting the system of the
Rhine, and mark out the winding of the coasts, bathed by the
sea during that period of tranquillity which succeeded those
commotions, the effects of which have been so well preserved.

VIL. System of the South-west coasts of Britanny, of La Vendée,
of Morvan, of the Bihmerwaldgebirge, and of the Thuringerwald.
—The oolitic series, comprising the lias and its inferior sand-
stone, has been deposited in an assemblage of seas and gulfs
which marks out the windings of the various systems of moun-
tains above noticed, and at the same time those of a peculiar

2K2 system,

252 Elie de Beaumont’s Researches on some of

system, distinguished by the N.W. and S.E, direction of the
greater part of its ridges and valleys, and by the beds of the
red or variegated sandstone (grés bigarré), the muschelkalk,
and the variegated marls (marnes irisées) being thrown out of
their original position, as well as all the more ancient rocks.
In the centre of France, near Avallon and Autun, the granitic
and porphyritic protuberances of Morvan stretch from N.W.
to S.E., disturb the coal-measures, and raise a peculiar arkose,
contemporaneous with the variegated marls, to their summits ;
whilst the lias and another arkose, which forms its lowest part,
extend horizontally to the feet of the same protuberances and
form the plains which surround them. The same direction,
and in part the same geological circumstances, are observable
in the hills, partly granitic, of the S. W. coast of Britanny and
La Vendée. These circumstances also appear in that part
of the Bohmerwaldgebirge which separates Bavaria from Bo-
hemia, in the Thuringerwald, and in the lines of disturbance
in the muschelkalk and the variegated marls (euper) which
according to the excellent map of M. Hoffmann run in the
same manner from S.E. to N.W. across the nearly flat coun-
tries situated between the Hartz and the Taunus. It therefore
appears that the elevation of the different parallel chains above
mentioned, is referrible to that revolution on the surface of
the globe to which the sudden difference observable between
the variegated marls and the lias is due.

VII. System of the Pilas, the Cote @ Or, and of the Erzge-
birge.— Professor Sedgwick has summed up, in his last Address
to the Geological Society of London, our knowledge respect-
ing this system. It includes (in Eastern France) the higher
elevations of the Céte d’Or and Mont Pilas, the Cevennes,
and a portion of the Jura chain. It may be traced towards
the valley of the Rhine, where it is suddenly cut off; but it re-
appears in the chain of the Erzgebirge, between Bohemia and
Saxony. It never rises into mountains of the first order, but
is marked throughout (as may be seen on a good physical map)
by many longitudinal ridges and furrows, ranging nearly pa-
rallel to each other in a direction about north-east and south-
west. So far the statement is only an enumeration of certain
connected facts in physical geography. But it is followed by a
coordinate series of geological phaenomena.

A number of formations, including in the ascending order
the whole oolitic series, enter here and there into the compo-
sition of the geographical system above described ; and, with-
out exception, wherever they appear all are in turn elevated,
broken, or contorted; yet in their lines of range they pre-
serve a parallelism to the general direction of the ridges. On

the

the Revolutions which have taken place on the Globe. 253

the contrary, wherever rocks of an age not older than that of
the green-sand or chalk, appear in the vicinity of any portion
of this system, they are either found at a dead level and
expanded from the neighbouring mountains into horizontal
planes, like the sea at the base of a lofty cliff; or if, since their
first deposit, they have undergone any great movement, it is
shown to have no relation to the bearing of the older ridges,
and to have been produced at a later period.

From all these combined facts follow three important con-
sequences. Ist, That the whole system of parallel ridges, from
one end to the other, was elevated at the same period of time,
after the development of the oolitic series, and before the de-
position of the green-sand and chalk. 2ndly, That the action
of elevation was violent and of short continuance, for the in-
clined strata are shattered and contorted; and between them
and the horizontal strata there is no intermediate gradation of
deposits. 3rdly, That the. period of elevation was followed by
an immediate change in many of the forms of organic life.

VILI. System of Mont Viso.—The French Alps and the
S.W. extremity of the Jura, from the environs of Antibes
and Nice to those of Pont d’Ain and Lons-le-Saulnier, present
a series of crests and dislocations with a direction towards the
N.N.W., in which the older beds of the Wealden formation,
the green-sand, and the chalk, are upheaved as well as those
of the oolitic series. The pyramid of primitive rocks of
Mont Viso is traversed by enormous faults, which from their
direction evidently belong to this system of fractures. The
eastern crests of the Devolny, north from Gap, are composed
of the most ancient beds of the system of green-sand and chalk,
thrown up in the direction in question, and elevated more
than 4700 English feet above the level of the sea, At the
feet of these enormous escarpments, are horizontally deposited,
near the Col de Bayud, and at more than 2000 feet lower
down, those upper beds of the cretaceous system which are
distinguished from the rest by the presence of Nummulites,
Cerithia, Ampullaria, and other shells, the genera of
which were long considered as not extending deeper in the
series than the tertiary rocks. Thus it was between the two
portions of that which is commonly termed the series of the
Wealden formation, green-sand, and chalk, that the beds of
the Mont Viso system have been upraised.

IX. Pyreneo-Apennine System. — Professor Sedgwick pre-
sented a summary of this system, in his last Address to the
Geological Society of London, and I must not omit to men-
tion that important parts of the whole evidence were added
by Professor Sedgwick himself and Mr. Murchison, during

their

254 Elie de Beaumont’s Researches on some of

their last travels on the Continent. This system includes the
whole chain of the Pyrenees, the northern and some other
ridges of the Apennines, the calcareous chains to the N.E. of
the Adriatic, those of the Morea, nearly the whole Carpathian
chain, and a great series of inequalities continued from that
chain through the N.E. escarpment of the Hartz mountains
to the plains of Northern Germany. Through the whole of
these vast regions the principal inequalities range nearly pa-
rallel to each other, and have a mean bearing about west-north-
west and east-south-east. So far again the statement is purely
geographical, and its truth is seen at once in glancing over
any good physical map of Europe; and will be still more clearly
comprehended, by comparing some of the principal ranges of
colour on Von Buch’s great geological map with the bearing
of the Pyrenees. But it is followed by a series of co-extensive
geological phenomena.

Through all parts of this great system, formations of the
age of the green-sand and chalk have had an enormous deve-
lopment, and without exception, their strata are ruptured and
contorted, and often lifted up to the very pinnacles of the
mountains. But on the contrary, wherever any tertiary for-
mations approach the confines of this system, they are stated
to be either in a position almost as horizontal as the surface
of the waters in which they were deposited; or if they have
been moved at all, it is by forces uninfluenced by the parallels
of the older chains. And the same three conclusions, with
a mere difference of dates, follow here as in the former case.
All the great parallel ridges and chains of this second system
must have been suddenly and violently elevated, and at a pe-
riod of time between the deposition of the chalk and the com-
mencement of the tertiary groups; and the corresponding
change in organic types is, in this instance, still more striking
than in the former.

X. System of the Islands of Corsica and Sardinia. — The
beds named tertiary are far from constituting a continuous
whole. Many interruptions are observable in them, each of
which may have corresponded with an elevation of moun-
tains effected in countries more or less near our own.

An attentive examination of the nature and geographical
disposition of the tertiary rocks in the north and south of
France, has led me to divide them into two series: one, which
is composed of the plastic clay, the calcaire grossier, and the
whole gypseous formation, including the upper marine mars,
scarcely passes to the S. or S.W. of the environs of Paris;
whilst the other, represented in the North by the grés de Fon-
tainebleau, the upper freshwater formation, and the fahluns,

comprises,

the Revolutions which have taken place on the Globe. 255

comprises, with few exceptions, nearly the whole tertiary de-
posits of the South of France and Switzerland, and especially
the lignite deposits, such as those of Fureau (Bouches du Rhone),
and Keepfnach (Switzerland). The grés de Fontainebleau,
resting on the marls of the gypseous formation, is the lowest
portion of this series, in the same manner that the lias sand-
stone, resting on the variegated marls (marnes irisées), is the
lowest portion of the oolitic series. The former is to the ter-
tiary arkose of Auvergne, what the latter is to the Jurassic
arkose of Avallon. ‘The two tertiary series are not less di-
stinguished by the remains of the large animals which they
contain, than by their mode of occurrence. Certain species
of Anoplotherium and Palcotherium discovered at Montmartre,
characterize the former, whilst other species of Paleotherium
and nearly all the species of the genus Lophiodon, the whole
genus Anthracotherium, and the more ancient species of the
genera Mastodon, Rhinoceros, Hippopotamus, Castor, &c., cha-
racterize the latter.

The line of demarcation existing between the first and se-
cond of these tertiary series would appear to correspond with
the elevation of the system of mountains under consideration,
the predominant direction of which is from north to south,
The beds of the second series are, in fact, those which alone
mark out the boundaries of the mountains.

Among the dislocations with a north and south direction,
we find the chains which border the high valleys of the Loire
and Allier, in a similar line of bearing to which are the vol-
canic masses of the Dome mountains, and at the bottoms of
which the fresh-water rocks of Limagne, of Auvergne, and
of the high valley of the Loire have been accumulated. The
valley of the Rhone which, quitting Lyon, also runs in a north
and south direction, is in like manner filled up to a certain
level by a tertiary deposit, the inferior beds of which, analo-
gous to those of Auvergne, are also of fresh-water origin,
while the upper beds are marine, and in a great measure cor-
respond with the fahluns of Touraine.

The same direction is observable in the islands of Corsica
and Sardinia, in many valleys and small chains of the Apen-
nines and of Ystria, in the disposition of many volcanic masses
and metalliferous sites of Hungary, and the chain which,
commencing in the middle of Servia with the Caponi, is
prolonged, parallel to the meridian between Macedonia and
Thessaly on the one side, and Albania on the other, bordering
the valleys of the Drino and the Arta on the east. .

It is worthy of remark, that the directions of the system of
the Pilas and the Cote d’Or, of the system of the Pyrenees,

and

256 Elie de Beaumont’s Researches on some of

and that of the islands of Corsica and Sardinia, are respectively
nearly parallel to those of the system of Westmoreland and the
Hundsruck, of the system of the Ballons and the hills of the
Bocage, and of the system of the North of England. The cor-
responding directions only differ in a few degrees, and the two
series have succeeded each other in the same order; leading to
the supposition that there has been a kind of periodical recur-
rence of the same, or nearly the same, directions of elevation.
XI. System of the Western Alps.—The opinions in accord-
ance with which M. Jurine named the granitic rock constitu-
ting Mont Blanc Protogine, can no longer be sustained. The
tertiary beds which have been deposited horizontally in that
part of the valley of the Rhone which runs N. and S. are
constantly contorted and thrown up as they approach the
Alps. A similar observation has been made in the valley of
the Danube by Professor Sedgwick and Mr. Murchison, who
found the cretaceous and tertiary beds to extend horizontally
to the foot of the Bohemian mountains, and to be thrown up
on entering the Austrian Alps. Messrs. Lyell and Murchi-
son have made analogous observations on the tertiary rocks
of Lombardy. Professor Buckland and M. Brongniart have
pointed out the tertiary aspect of the fossil shells discovered
at the Diablerets, at more than 8000 feet above the level of
the sea; shells the relative age of which certainly does not go
back beyond the last portion of the cretaceous epoch.
Although we are generally accustomed to consider the
union of those mountains bearing the single name of the Alps
as constituting an undivided whole, we can easily recognise
that this vast assemblage is due to the crossing of several
systems, independent of each other, and distinct both in age
and direction. We should therefore not feel surprise that
their structure is more confused than that of a chain thrown
up by a single effort, such as the Pyrenees. Throughout nearly
their whole extent, and especially on their eastern side, we
still perceive traces of numerous small chains of mountains
with the same direction as the Pyrenees, and elevated in like
manner prior to the deposition of the tertiary rocks. The
system of Mont Viso is strongly marked in the French Alps.
These traces of comparatively ancient dislocations are, how-
ever, often marked by disturbances of a more recent date.
The highest and most complicated portions of the Alps,
those near the Mont Blanc, Mont Rose, and the Finsteraar-
horn, are principally due to the crossing of two recent systems
which meet at an angle of from 45° to 50°, and which are di-
stinguishable from the system of Mont Viso and the Pyreneo-
Apennine system, as well by their age as their directions. In
consequence

the Revolutions which have taken place on the Globe. 257

consequence of the crossing of these two systems of furrows
and ridges, the French Alps form an elbow near the Mont
Blanc, and after having followed a direction from E. }° N.E.
to W. 34° S.W. from Austria to the Valais, they suddenly
turn to fall into a line from N.N.E. to S.S.W. If there was
only a simple curve m a single chain of mountains which
merely formed an arch, we should find the direction of the
beds to bend and pass from the direction of one of the sy-
stems to that of the other. We however observe, that the
direction of the beds and crests distinctly belong either to one
or to the other, and that the two systems penetrate each other,
as we should conceive they must do if they are the produc-
tions of two entirely distinct phenomena.

In the Western Alps, that is to say, to the westward of the
St. Gothard, and particularly in the mountains of Savoy and
Dauphiny, the greater part of the dislocations are referrible
to two systems of ridges, the mean direction of which is N.N.E.
and S.S. W., or more exactly N. 26° E., and S. 26° W. The
constant direction of the beds in these mountains has long
since been remarked by De Saussure, and more recently by
M. Brochant; and they with reason concluded, that in all those
parts where this direction predominated, the beds were thrown
up by a single operation of nature.

It is easy to determine the geological date of this event; for
we have only to examine what are the formations which have
been disturbed, and what the deposits which extend horizon-
tally on the edges of the dislocated and more ancient strata.

In the interior of that system of ridges of which the Western
Alps are principally composed, we do not find beds more re-
cent than the chalk, because these ridges have been formed on
a surface previously made mountainous, at the epoch of the
systems of Mont Viso and the Pyrenees. But on the skirts,
as also at the two extremities of the space occupied by the
ridges to which the character of the Western Alps is due, we
find that the dislocations which have produced the ridges are
carried into the most recent tertiary deposits, as well as into
the secondary rocks which support them: whence it follows,
that the elevation of the beds in the system of the Western
Alps took place after the deposit of those recent tertiary beds,
named shelly molasse (mollasse coquilliére), beds contempo-
raneous with the fahluns of 'Touraine.

XII. System of the principal Chain of the Alps (from the
Valais to Austria), comprising also the Chains of the Ventoux,
the Liberon, and the St. Baume (Provence).—The valleys of
the Isére, the Rhone, the Saone, and the Durance, present
two very distinct detrital and transported formations, between

N.S. Vol. 10. No. 58. Oct. 1831. 2L which

258 Elie de Beaumont’s Researches on some of

which there is a want of continuity, and a sudden variation
of character, constituting a new interruption in the series of
sedimentary deposits.

The waters which have transported the materials of the
first of these formations would appear to have been received
into lakes of fresh water which covered, in one direction, the
N.W. portion of the department of the Isére, La Bresse, and
perhaps, Alsace, and even the environs of the lake of Con-
stance; and in the other, the portion of the department of the
Basses Alpes between Digne, Manosque, and Barjols: whilst
the materials of the second formation appear to have been
violently carried by temporary currents which have discharged
themselves into the Mediterranean, These latter currents
are generally known as diluvial currents, though they offer
nothing in common with the Deluge of history, and though
their passage took place before the human race appeared on
our continent, where they destroyed animals of species now
extinct. Discussions will still perhaps be carried on respect-
ing their origin, which may have merely been the result of
the melting of the snows, instantaneously effected when the
principal chain of the Alps was elevated ; but it seems generally
admitted that their passage immediately followed the last dis-
location of the Alpine strata.

If we cast a general glance on the Alps and neighbouring
countries, we may observe that the crests of the St. Baume,
the Lebaron, the Ventoux, and the Montagne de Poet, in the
South of France, the principal chain of the Alps from the
Valais to Austria, and the less elevated crest, comprising the
Pilate, &c. in Switzerland, are so many different chains, which,
notwithstanding their inequality, are comparable with each
other both as respects their parallelism and their common
analogies to the system of the Western Alps. This parallelism
and these analogies would alone afford us powerful reasons
for believing that the whole of these mountain-chains were
formed at the same time, and are only different parts of a single
system of fractures produced at the same moment. We can
at furthest conceive the idea of dividing them into two groups,
—that of Provence, and that of the Alps; but we are prevented
from doing this by the analogous relations observable among
the different fractures, and by a general movement which we
may consider the surface of a part of France to have suffered
when it contracted a double slope; ascending in one direction
from Dijon and Bourges towards Le Forez and Auvergne,
and on the other from the shores of the Mediterranean towards
the same countries. These opposed slopes present at their
junction a kind of crest, situated precisely in the line of eleva-

tion

the Revolutions which have taken place on the Globe. 259

tion of the principal chain of the Alps. This line, which may
be observed to run ina more or less marked manner from the
confines of Hungary to Auvergne, appears to be connected
with the principal anomalies unveiled in the interior structure
of our continent by geodesical measurements and observations
with the pendulum. We may even suppose that the forma-
tion of this line gave, as it were, the signal for the appearance
of the craters of elevation of the Cantal and Mont d’Or, round
which the volcanic cones of Auvergne have been subsequently
thrown up.

The two opposite slopes, above mentioned, were not pro-
duced until after the existence of those lakes in which the
older transported substances were accumulated ; for it can be
ascertained that the bottom of the lake which covered La
Bresse and the N.W. portion of the department of the Isére
has suffered a considerable elevation from the north towards
the south, and that the bottom of the lake which extended
between Digne, Manosque, and Barjols, has been elevated to
a great degree from the south towards the north,

The ancient deposits of transported substances, forming
horizontal beds at the bottom of the latter of these lakes, on
the edges of tertiary deposits, previously dislocated when the
Western Alps were thrown up, are in their turn dislocated near
Mezel (Basses Alpes) in the direction of the small chains which
ridge Provence, such as the Ventoux and Lebaron, parallel
to the principal chain of the Alps.

To determine the date of this last order of dislocations it
will be sufficient to remark, that the diluvian deposit is in no
part affected ; that it covers the edges of the dislocated beds
with no other slope than that which the current impressed on
them at their origin; and that thus the elevation of the beds
in question necessarily took place between the older deposit of
transported substances and the passage of the diluvian cur-
rents.

If we attentively consider, on a terrestrial globe of suffi-
cient size and good execution, the most prominent and the
most recent systems of mountains which ridge Europe, we
may remark that each of them forms a part of a vast system
of parallel chains, which extends far beyond the countries
geologically known to us. But as in all the parts of each of
these systems situated in well examined portions of Europe,
it has been more and more observed that parallel chains are
in general contemporaneous, there is no reason to suppose
that this law should suddenly cease, if its verification should
be pushed still further, It is therefore natural to consider,
until direct observations may show the contrary, that each of

2L2 these

260 Elie de Beaumont’s Researches on some of

these vast systems, of which the European systems are re-
spectively portions, originates in a single epoch of dislocation.
From this view I am led to suppose, for example, that the
principal chain of the Alps is contemporaneous with a vast
assemblage of mountain-chains which spread round the Medi-
terranean, and being prolonged across the continent of Asia,
run paraliel to a great circle which should pass through the
middle of Morocco and the north of the Birman empire, and
appear at the same time connected with each other by paral-
lelism and by the similarity of their relations to the great de-
pressions of surface filled by the sea, or but slighty raised
above its level. Besides the principal chain of the Alps,
and the small chains of Provence, this system comprises, in
Europe, the Sierra Morena, and a large portion of the Spa-
nish chains, on the one hand, and the Balkan on the other: in
Africa, it includes the Atlas: in Asia, the central trachytic
chain of the Caucasus, crowned by the peak of Elbrouz, more
elevated than the Mont Blanc, as also the long series of moun-
tains which under the names of Paropamissus, Indou-Kosh,
and Himalaya, bound the plains of Persia and Bengal, and
contain the most elevated mountains on the surface of the
earth.

Iam also led to suppose that the system of the Western Alps
constitutes a portion of a vast system, comprising the chain of
Kiol in Scandinavia, the chains which in Morocco run from
Cape Tres Furcas to Cape Blanc, and the Littoral Cordilera
of Brazil.

Finally, I am led to suppose that the chains of the Pyreneo-
Apennine system observed in Europe, form a portion ofa vast
system comprising certain chains in the north of Africa, of
Egypt, of Syria, of the Caucasus, the chains which bound
Mesopotamia on the north-east, and even the Ghauts of Mala-
bar, and which appears in another direction, across the Atlan-
tic, in the Alleghanies.

The appearance of a new system of mountains which,
judging from the result of our observations, has produced
such violent effects on countries near them, could only have
exercised an influence in distant countries by the agitation
caused in the waters of the sea, and by a greater or less change
produced in their level,—events which may be compared to the
sudden and passing deluge noticed among the traditions of all
nations as having occurred at nearly the same epoch. If this
historical event was the last which has taken place on the sur-
face of the globe, we are naturally led to inquire which is the
mountain-chain referrible to the same date: and perhaps we
may be justified in observing that the chain of the Andes, Hl

volcanic

the Revolutions which have taken place on the Globe. 261

volcanic vents are still in activity, (or more exactly the long
cliff (_falaise) surmounted or bounded by volcanos which run
on a great semicircle of the earth from Chili to the Birman
country,) presents the most extensive, the most clearly defined,
and as it were the least obliterated feature observable in the
present exterior configuration of the globe.

It has been shown, as Professor Sedgwick justly observes,
that paroxysms of internal energy, accompanied by the eleva-
tion of mountains, and followed by mighty waves desolating
whole regions of the earth, were a part of the mechanism of
Nature; and what has happened again and again, from the
most ancient up to the most modern periods, may have hap-
pened once during the few thousand years that man has been
living on its surface. We have therefore taken away all an-
terior incredibility from the fact of a recent deluge.

If the general result of the preceding observations be exact,
we may briefly express it by saying, that the independence of
sedimentary formations is both a consequence and proof of
the independence of mountain-systems. having different direc-
tions. Many traces of interruptions in the series of sedimen-
tary deposits are, perhaps, so slight in Europe, only because
they correspond with mountain-systems which, like that so
strongly marked on the shores of Mozambique and Madagas-
car, have not sent any ramifications into our countries.

But if the number of the surface-revolutions of the globe,
and of really distinct mountain-systems be still undetermined,
and if the series formed by these successive terms be still im-
perfectly known, the observations already made nevertheless
circumscribe within certain limits that law, which when they
shall be all completely known may be manifested in their suc-
cession. From the circumstance of the present heights of
Mont Blanc and Mont Rosa, dating only from the later sur-
face-revolutions of the globe, it is clear, that whatever defini-
tive place other and higher mountains may occupy in the same
series, this series will never take that gradually and regularly
decreasing form which should lead to the conclusion, that the
limit was attained. Nothing will show that phenomena the
last paroxysms of which have been so violent should not
be reproduced. However provisional the succession of terms
may be which results from the preceding memoir, it is diffi-
cult to foresee a modification which should so change its
' aspect, as to lead to the supposition, that the mineral crust of
- the globe has lost the property of being successively ridged in
various directions. It is difficult to conceive a change which
would permit us to assure ourselyes that the period of tran-

quillity

262 Elie de Beaumont’s Researches on some of

quillity in which we live will not be disturbed in its turn by
the appearance of a new system of mountains, the effect of a
new dislocation of the land we inhabit, and of which earth-
quakes teach us the foundations are not immovable.

The independence of successive sedimentary formations is
the most important result obtained from the study of the su-
perficial beds of our globe; and one of the principal objects
of my researches has been to show, that this great fact is a
consequence, and eyen a proof, of the independence of moun-
tain-systems having different directions.

The fact of a general uniformity in the direction of all beds
upheaved at the same epoch, and consequently in the crests
formed by these beds, is perhaps as important in the study
of mountains, as the independence of successive formations is
in the study of superimposed beds. The sudden change of
direction in passing from one group to another has permitted
the division of European chains into a certain number of
distinct systems, which penetrate, and sometimes cross each
other without becoming confounded. I have recognised from
various examples, of which the number now amounts to twelve,
that there is a coincidence between the sudden changes esta-
blished by the lines of demarcation observable in certain con-
secutive stages of the sedimentary rocks, and the elevation of
the beds of the same number of mountain-systems.

Pursuing the subject as far as my means of observation and
induction will permit, it has appeared to me, that the different
systems, at least those which are at the same time the most
striking and recent, are composed of a certain number of
small chains, ranged parallel to the semicircumference of the
surface of the globe, and occupying a zone of much greater
length than breadth; and of which the length embraces a
considerable fraction of one of the great circles of the ter-
restrial sphere. It may be observed in support of the hy-
pothesis of each of these mountain-systems being the product
of a single epoch of dislocation, that it is easier geometrically
to conceive the manner in which the solid crust of the globe
may be elevated into ridges along a considerable portion of
one of its great circles, than that a similar effect may have been
produced in a more restricted space.

However well established it may be by facts, the assem-
blage of which constitutes positive geology, that the surface
of the globe has presented a long series of tranquil periods, *
each separated from that which followed it by a sudden and
violent convulsion, in which a portion uf the earth’s crust was

dislocated, —that, in a word, this surface was ridged at intervals
in

the Revolutions which have taken place on the Globe. 263

in different directions; the mind would not rest satisfied if it
did not perceive, among those causes now in action, an ele-
ment fitted from time to time to produce disturbances dif-
ferent from the ordinary march of the phznomena which we
now witness.

The idea of volcanic action naturally presents itself when
we search, in the existing state of things, for a term of com-
parison with these great phenomena. ‘They nevertheless do
not appear susceptible of being referred to volcanic action,
unless we define it, with M. Humboldt, as being the influence
exercised by the interior of a planet on its exterior covering
during its different stages of refrigeration.

Volcanos are frequently arranged in lines following frac-
tures parallel to mountain-chains, and which originate in the
elevation of such chains; but it does not appear to me that
we can thence regard the elevation of the chains themselves as
due to the action of volcanic foci, taking the words in their
ordinary and restricted sense. We can easily conceive how
a volcanic focus may produce accidents circularly and in the
form of rays from a central point, but we cannot conceive how
even many united focz could produce those ridges which follow
a common direction through several degrees.

Volcanic action, such as it is commonly understood, could
not therefore be itself the first cause of these great phzeno-
mena; but volcanic action appears to be related (and this is
a subject which has long occupied M. Cordier, though he has
considered it under another point of view) with the high tem-
perature now existing in the earth.

Now the secular refrigeration, that is to say, the slow dif-
fusion of the primitive heat to which the planets owe their
spheroidal form, and the generally regular disposition of their
beds from the centre to the circumference, in the order of
specific gravity,—the secular refrigeration, on the march of
which M. Fourier has thrown so much light, does offer an
element to which these extraordinary effects may be referred.
This element is the relation which a refrigeration so advanced
as that of the planetary bodies establishes between the capa-
city of their solid crusts and the volume of their internal
masses. In a given time, the temperature of the interior of
the planets is lowered by a much greater quantity than that on
their surfaces, of which the refrigeration is now nearly insen-
sible. We are, undoubtedly, ignorant of the physical pro-

erties of the matter composing the interior of these bodies ;
But analogy leads us to consider, that the inequality of cooling
above noticed would place their crusts under the necessity of
continually

264 Mr. Blackwall on a new Species of Hawk.

continually diminishing their capacities, notwithstanding the
nearly rigorous constancy of their temperature, in order that
they should not cease to embrace their internal masses ex-
actly, the temperature of which diminishes sensibly. They
must therefore depart in a slight and progressive manner
from the spheroidal figure proper to them, and corresponding
to a maximum of capacity; and the gradually increasing
tendency to revert to that figure, whether it acts alone, or
whether it combines with other internal causes of change
which the planets may contain, may, with great probability,
completely account for the ridges and protuberances which
have been suddenly formed at intervals on the external crust
of the earth, and probably also of all the other planets.

XXXIII. On an undescribed Bird of the Family Falconidz.
By Joun Brackwat1, Esq. F.L.S. &c.*

[pUENc the last two years, five specimens of a minute
Hawk, no account of which, there is reason to believe,
has yet been published, have been brought to Manchester, at
different periods, from Brazil. On inspecting this new species,
it is evident from several peculiarities in its organization, that
it should occupy a situation, in a natural arrangement of birds,
intermediate between the Hawks and true Falcons; as it unites
in itself certain features characteristic of each of those groups.
Its short bill, curved from the base, the upper mandible of
which is furnished on each side with a small festoon; the
shortness of its wings, notwithstanding the second quill-feather
is the longest, and the first has the inner web slightly emar-
ginated near its termination; the moderate length of the tail
and legs; the reticulated tarsi, and the acrotarsia feathered
from the knee to the middle,—plainly indicate that it must be
referred to the genus Gampsonyz, established by Mr. Vigors.

Order. Raptores. Illiger.
Family. Falconida. Leach.
Subfamily. Accipitrina. Vigors.
Genus. Gampsonyz. Vigors.

G. Holmii. The bill, which is much curved, is black faintly
tinged with blue. Plumage on the forehead and cheeks
pale orange; that on the top of the head, back, scapu-
lars and upper part of the wings, dark cinereous brown.
Greater wing-coverts and feathers of the spurious wings

* Communicated by the Author.
white

Mr. Brooke on Monticellite, and other Minerals. 265

white at their extremities. Each quill-feather of the
wings has a broad margin of white on its inner web,
and the secondaries and tertials are tipped with white.
Upper tail-coverts and feathers of the tail deep cine-
reous; the latter, with the exception of the two mid-
dle ones, which are plain, having a border of white
on their inner webs. A white collar passes over the
back part of the neck, immediately behind which is a
narrow parallel band of a chestnut colour. On each
side of the breast a black spot is conspicuous. All the
inferior parts are white except the thighs, which are of
a bright rust colour, and the under coverts of the wings,
which exhibit a slight tint of the same hue. Legs and
feet yellow. Claws dark horn colour inclining to black.
Colour of the eyes not known. Total length 9 inches ;
wings, from the carpus to the tip of the second quill-
feather, 5,2, ; upper mandible, from the point to the gape,
in a straight line, ;; under mandible, ;° ; tarsi, 1.

The specimen from which the foregoing description was
taken occupies a place in the Manchester Museum.

That G. Holmii bears a striking resemblance to the
G. Swainsonii of Mr. Vigors cannot be denied; the white
collar and chestnut-coloured band on the neck of the former,
and the pure white plumage of its abdomen, constituting the
most obvious points of difference between the two species.

To Edward Holme, M.D., the learned and accomplished
President of the Natural History Society of Manchester, (who
has uniformly promoted my zoological investigations by every
assistance which his extensive knowledge and valuable library
could supply,) this bird is respectfully dedicated.

XXXIV. On Monticellite, a new Species of Mineral; on the
Characters of Zoizite; and on Cupreous Sulphate of Lead.
By H.J. Brooke, Esq. F.R.S. LS. §& G.S.*

Monticellite.
I OBTAINED a year or two since from Mr. G. B. Sowerby,

a specimen said to have come from Vesuvius, containing
some imbedded crystals of a substance which I believe has
not been before noticed, and of which I am not aware of having
seen any other specimen. The matrix is crystalline carbonate
of lime; and besides the mineral I am about to describe, it
contains particles of black mica, and some minute crystals of
pyroxene. On the supposition of its being an undescribed mi-
neral, and from Vesuvius, I have named it after Mr. Monti-

* Communicated by the Author.

N.S. Vol. 10. No. 58, Oct. 1831. 2M celli,

266 Mr. Brooke on Zoizite.

celli, who has published a work in illustration of the minerals
found in the neighbourhood of that mountain. The general
aspect of the crystals is that of quartz, and might by a cur-
sory observer be mistaken for it. The colour generally is
yellowish, but there are some crystals nearly colourless and
nearly transparent; and on placing a portion of the specimen
in dilute muriatic acid to dissolve the carbonate of lime, I
found that the surfaces of the yellowish crystals became dull,
and were covered with a yellowish powder, leaving the crystals
less coloured than they were at first.

The primary form is a right rhombic prism of about 132° 54’,
a terminal edge being to a lateral edge as 1 to 1-046 very
nearly.

I have not observed any cleavage planes on the fractured
surfaces, and the crystals are too small to allow of much other
examination in this respect. The hardness is between that of
apatite and felspar. ‘There is no crystal sufficiently free from
the matrix to allow of the specific gravity being ascertained ;
nor are the surfaces of the crystals sufficiently perfect to afford
very accurate measurements. ‘The following therefore may
admit of some slight correction :

Plaviés®s KOR. ieee, Fe

a Sigh ey
Symbols .....sessseeees Be By G:
M,M'= 132° 54!

M,e = 145 00

ee = 141 48

hc = 138 46

Mk) = 113. 33
Zoizite.

This mineral has been confounded with Epidote by Haiy,
probably from the occurrence of crystals of that substance in
the Zoizite of Hoff; and in this mistake he has been followed
by most other writers on the subject.

The late W. Phillips says, * it cleaves parallel to the planes
of a right rhombic prism of about 60° and 120°.”

Mr. Haidinger, in his Treatise on Mineralogy, says that
Epidote and Zoizite are easily distinguished by their colours.
And in reference to the angle which I had given as that of
Zoizite, differing from the angle of Epidote, he says; ‘ this
would render it necessary to consider Zoizite as a particular
species.” Hence it is clear that Mr. Haidinger could not
have examined this mineral; for ifhe had, he must immediately
have perceived its difference from Epidote.

I have lately obtained a small crystal of Zoizite with terminal

planes,

Mr. Brooke on Cupreous Sulphate of Lead. 267

planes, from which it is evident that the primary form is an
oblique rhombic prism, and from the angles given below it
approaches very nearly, if it be not the same as that of
euclase. It has also a bright cleavage through the oblique
diagonal, similar to that of euclase, and no very distinct
cleavage in any other direction.

The annexed figure exhibits the form of the crystal I have
alluded to, the terminal planes of which are, however, too
imperfect to afford accurate measurements.

ela = 193° 30! (about)*

ac = 107 20 ... Pyc9 = 107° 20!
pe "et 45°... Pct = 120 30
a == 145 20

bb’ = 116 30

The perfect identity of the forms of Zoizite and Euclase
depends obviously on the relative démensions of the primary
forms, as well as upon the angles of the prisms; and as those
dimensions can be deduced only from accurate measurements
of the terminal planes, it is to be hoped that those who possess
better crystals will supply the deficient angles, and complete
the description of the form.

Cupreous Sulphate of Lead.

A specimen I have lately obtained of this substance has
enabled me to give the annexed figure and measurements of
the crystals. ‘The primary form is an oblique rhombic prism,
a terminal edge of which is to a lateral edge as 19 to 8 very
nearly, the plane angles of the terminal plane at the extre-
mities of the oblique diagonal being 59° 12’.

Planes ...... cl, €2, ¢c3, C4, c5y h.

Symbols....

PB

P,c3

Pyct

Pyc5

M,M’ =

* Corresponding planes of euclase, as measured by W. P. (See his
figure.)

2M2 Hemitrope

268 Mr. Daniell on a New Register-Pyrometer,

Hemitrope crystals occasionally present themselves, the
plane of revolution being parallel to the plane 4, which trun-
cates the edge of the prism. The angle at which the two
planes P then intersect each other, is 154° 30!.

XXXV. On a new Register-Pyrometer, for Measuring the
Expansions of Solids, and determining the higher Degrees
of Temperature upon the common Thermometric Scale. By
J. Freperic Daniewy, Esq. F.R.S.

[Continued from p, 199.]

| SHALL now proceed to show the degree of confidence
which may be placed in this new pyrometer, by comparing
the result of its indications with those of the best experiments
upon the expansion of metals. Those of MM. Dulong and Pe-
tit* are well adapted to this purpose. These able philosophers,
in their celebrated prize Memoir on the Measure of ‘Tempe-
ratures, and on the Laws of the Communication of Heat, have
given, from experiment, the expansion of rods of platinum
and iron at different intervals between the freezing point of
water and the boiling of mercury. Their mode of experi-
menting was unexceptionable; but it is to be regretted that
they have not corrected their final results for an error of cal-
culation which has been pointed out by Mr. Crichton+ which
is by no means unimportant to the reasoning which they have
founded upon them. The error, however, affecting the amount
of expansion in volume, is reduced to one-third in the linear
expansion, which is the subject’of the present investigation, and
may therefore be disregarded.
The following Table of the expansion of iron and platinum
is extracted from their work.

Taste II.
Temperature deduced Mean absolute Mean absolute
from the Dilatation Dilatation cf Iron | Dilatation of Platinum

of Air. for 180 degrees. for 180 degrees.

° ° pi Dey othe

From 32° to 212 28200 37700

° ° 1 pes: wis.

From 392° to 572 22700 36300

Whence we deduce the linear expansion of platinum for
180° Fahrenheit, from 32° to 212° ‘00088420: and for 180°,

* Ann. de Chimie et Physique, vii. 113.
+ Annals of Philosophy, New Series, vol. vii. p. 241.
from

for Measuring the Expansions of Solids, §c. 269

from 392° to 572° 00091827: and of iron, from 32° to 212°
00118203: from 392° to 572° -00146842, showing an increas-
ing dilatation in each when referred to an air-thermometer.

The bars of the different metals used in the following expe-
riments were all exactly 6°5 inches in length.

Exp. 1. A square bar of platinum 5%ths of an inch thick,
was carefully arranged in the black-lead register, which was
placed in the apparatus represented, upon a diminished scale,
at fig. 3. (Plate II.) ais an iron tube about two inches diameter,
and closed at the botom: 0 is a black-lead tube closed at the
top, and fitted to the mouth of the former by grinding: c is a
smaller black-lead tube projecting from the side of the latter
near its upper end, and likewise fitted to its place by grinding.
The whole forms a kind of alembic, which may be readily put
together, and in which mercury may be easily boiled on a
common fire, and the vapours collected without loss or an-
noyance to the operator. The register was fixed in its place
by a wire, so that when mercury was poured into the iron
bottle it was prevented from floating. ‘The mercury in this
experiment rose a little above half the length of the register.
The whole apparatus was then placed upon a fire, and in ten
minutes the mercury began to boil: in ten minutes more it
freely distilled over; and in ten minutes further the apparatus
was removed, the register taken out and allowed to cool. The
arc measured upon the scale was in this instance 1° 17/.

The experiment was repeated, merely having the head of the
alembic off, and suffering the mercury to boil freely in the iron
bottle for a quarter ofan hour. The arc measured was 1° 23'.

The register was next allowed to float upon the mercury,
so that when the head of the alembic was adjusted and the
mercury made to boil, it was not immersed in the metal, but
surrounded by its vapour: the reading was 1° 16'. A repeti-
tion of this arrangement gave 1° 23.

In another repetition of the experiment, the time was ex-
tended to twenty minutes from the first boiling of the mercury;
the reading of the scale was 1° 20.

Again; the time was reduced to ten minutes, and the
measurement was 1° 23'.

In the various repetitions of this experiment the mercury
freely distilled over, and the temperature was such, that every
part of the black-lead tubes, in which the vapour circulated,
would just scorch, but not blacken, a piece of writing paper
held against them.

The following Table collects these results into one view, and
exhibits the expansion denoted by each reading, and the mean
result,

TABLE

270 Mr. Daniell on a New Register-Pyrometer,

Taste III.
1°17!/)=-01119
1 23 = °01206
116 = :01105
1 23 = :01206
1 20 = +011638
1 23 = :01206—Mean 1° 20' = ‘01163.

The temperature of the atmosphere was about 64° during
these observations.

Exzp.2. <A bar of soft iron, of the same dimensions as that
of platinum, was substituted for the latter in the register. The
experiment was repeated five times; twice with the register
immersed in the mercury, and three times exposed only to the
vapour. The time of exposure varied from twenty minutes
to ten, from the first moment when the metal began to boil.

The following Table exhibits the several readings and the
appropriate expansions.

Taste IV.

2°13' = :01933

2 33 = °02224

210 = :01890

2423 =) 02079

2 20 = :02036—Mean 2° 20! = 02036.
The greatest variation from the mean was therefore only
_, 6 —dths of an inch in the platinum experiment, and

10°000

ToGo dths in the iron.
We shall now compare these results with the preceding

determinations of MM. Dulong and Petit.

The Expansion of Platinum.
Length of Bar.

From 32° to 212° = *000884:20 X 6°5..00086. ='005747300
From 392° to 572° = *00091827 X6°5....666.. ="'005968755
°011716055

From 212° to 392° = Mean of the above.... =°005858027
Total expansion from 32° to 572° ...ssseseeeeeee ='017574082
Add for the expansion from 572° to 660°,
the temperature of boiling mercury, calculated
at the highest rate :—
180°: °005968755 : : 88° : 002918058.... =°002918058
~ 020492140
Deduct expansion for 32°, the experiment with
the pyrometer having been made at 64° ... =*001021742
Calculated at the lowest rate :—
180° : 005747300: : 32°: 001021742
Real expansion of the bar by Dulong and Petit =*019470398
If

for Measuring the Expansions of Solids, Sc. 271

If from the real expansion thus obtained......sseesee0e 01947
we deduct the apparent expansion obtained by the
PYEOMELEL os «oasis sinesiiagnintebeane we svie'ss seers env oecss'vessee 701163

the remainder -00784

will be the expansion of the black-lead.

The Expansion of Iron.
Length of Bar.
From 32° to 212° = 00118203 X6°5....00+. ='007683195
From 392° to 572° = *00146842 X 6'5...e0004. =°009544730

*017227925
From 212° to 392° = Mean of the above..... ='008613962

Total expansion from 32° to 572°..+eccceeeseee = "025841857
Add for the expansion from 572° to 660°,
the temperature of boiling mercury, calculated
at the highest rate :—
180° : 009544730: : 88°: '004666311.... =*004666311

‘030508198
Deduct expansion for 32°, the experiment with
the pyrometer having commenced at 64° .... =*001365901
Calculated at the lowest rate :— ens
180°: :007683195 : : 32°: °001365901
Real expansion of the bar by Dulong and Petit 029142297

From the real expansion.....cccssessersssereesecesceseseeee “O2Z914
deduct the apparent expansion obtained by the
PYTOMEHEL..cceeesecescensccccseveccuscssssvssccscasssccesses "02036

The remainder ‘00878
is again the expansion of the black-lead as obtained
by this series of,experiments.
Expansion of 6:5 inches of black-lead.
From 64° to 660° by platinum bar .......seeeeeeerrees “00784
by iron bar sesecessescseeesereeeereeee *OO87S

Mean 00831
either determination differing from the mean by less than
rospotths of an inch.

This close agreement in results from two metals whose
expansions differ so much from each other is highly satisfac-
tory; but the great delicacy of the instrument may be still
better appreciated from the following experiment of the ex-
pansion of nine different metals from the temperature of 62°
(the temperature of the air at the time of observation) to 212°.

Exp. 3.

272 Mr. Daniell on a New Register-Pyrometer,

Exp. 3. Bars of the following metals were successively
placed in the register and immersed in hot water, which was
gradually heated to the boiling point, and kept boiling for ten
minutes in each instance. The following Table exhibits the
readings of the scale and the appropriate expansions.

Tas._e V.
Platinum......... 0°19' = -:00276 from 60° to 212°

Iron (soft) ...... 0 35 = *00508

Copper... 0 47 = 00683 -——
Tin (grain)...... 0 56 = ‘00814 ——
ZiNC.ccccccccccseee 1 40 = 01454 ——
Leadishvassvsostons,, 1, 25, = OlZS ——.
Brass.....cc0000008 0 55 = ‘00799 - a
Gold (fine) ...... 0 36 = *00552 ———_
Silver (fine)...... 0 56 = ‘00814

In the subsequent Table, I have given the absolute expan-
sions of the same metals from 32° to 212° from the best au-
thorities; and for the sake of comparison have added from
calculation their expansion from 62° to 212°, by reducing the
former in the proportion of 180: 150.

Tasce VI.

Length of Bar. From 32°? to212°. From 62? to 212%. —_ Authorities.
Platinum -00088420 x 6-5 = -005747300 = -004789416 Dulong & Petit.

Iron...... :00118203 x 6-5 = -007683195 = -006402662 Dulong & Petit.
Copper... -00171821 X6-5 = -011168365 = -009306970 Dulong & Petit.
ane tecte: 00217298 x 6.5 = -014124370 = -011770308 Lavoisier & Lapl.

Zinc... .. 00294200 x 6-5 = -019123000 = -015935833 Smeaton.
Lead...... °00284836 x 6-5 = -018514340 = -015428616 Lavoisier & Lapl.
Brass..... °00193000 x 6-5 = -012545000 = -010454166 Smeaton.
Gold... .. -00146606 x 6-5 = -009529390 = -007941158 Lavoisier & Lapl.
Silver.... -00190974 x 6-5 = -012413310 = -010344424 Lavoisier & Lapl.

Upon deducting from the amount of these several absolute
expansions the apparent expansions in the black-lead register,
we shall obtain the expansion of the latter from 62° to 212°,
as derived from the several metals. The results are com-
prised in the following Table.

Taste VII.
Expansion of Difference

: Expansion of the Metal Rars. Black-lead Register. from Mean.
Platinum .... absolute -00478

apparent °00276

—— == £00 =°00202 eee —°00032
Tron ..seeeeee. absolute 00640

apparent 00508

eee =°00132 eee —’00102
Copper

for Measuring the Expansions of Solids, 8c. 273
Taste VII. (Continued.) bas

Expansion of Difference
Expansion of the Metal Bars. Black-lead Register. from Mean.

Copper...... absolute *00930
apparent ‘00683

oss == "OO2Z47 3... -- "00013
Tin ........... absolute ‘01177

apparent ‘00814

eee ='00363 eee +°00129
Zinc .....06. absolute *01593

apparent ‘01454

eee ="00139 ... —: 00095
Lead......... absolute ‘01542

apparent 01223

ee. ='003519 ... +:00085
Brass.....-+6. absolute °01045

apparent ‘00799

eee ='00246 ... +:°00012
Gold......... absolute -00794

apparent 00552 ...

00242 ... +:°00008

Silver ........ absolute 01034
apparent ‘00814

eee =*00220 eee —*00014
Mean 00234

In five instances out of these nine, the difference of the
expansion of the black-lead from the mean does not exceed
rod soodths of an inch, two being in deficiency, and three in
excess: and it is worthy of observation that they are the metals
whose dilatations have always been considered the most re-
gular, and concerning which there is the least difference of
authorities, viz. gold, silver, platinum, copper, and brass.
The greatest difference is in the tin, which amounts to nearly
70.0q0dths of an inch in excess; and it is more than probable
that the absolute expansion of this metal has not hitherto been
obtained with sufficient precision, and that it even varies in
different states. I shall return to this subject in the second
part of this paper, which I reserve for a future communication;
in which I hope to be able to lay before the Society observa-
tions and tables of the dilatations of metals to their melting
points. It is my intention in this first part to touch no further
upon the subject of expansion than is sufficient to establish
confidence in the pyrometer as a measure of heat.

Another confirmation of the precision of these observations
wy, be derived by calculating the expansion of the black-lead

S. Vol. 10. No. 58. Oct. 1831. 2N register

274 Mr. Daniell on a New Register-Pyrometer,

register for the 150°, from the greater expansion previously
determined by the boiling point of mercury for

596° : :00831 :: 150° : °G0209

which only differs +53%;5;dths of an inch from the above
mean.

Exp. 4. It was a principal object to ascertain whether any
and what difference existed in the expansion of different spe-
cimens of the black-lead earthenware: two or three registers
which I had cut out of the same crucible gave me almost
identical results by exposure to boiling mercury. I then se-
lected another specimen by a different manufacturer. Its
grain was very fine, and its texture more close and compact
than the former. It was twice exposed with the platinum bar
to boiling mercury. The first time it was boiled for a quarter
of an hour, and the arc measured was 1° 45’.. The second
time the boiling was continued for only ten minutes, and the
reading was precisely the same. ‘The expansion was there-
fore 01526.

Absolute expansion as before...... ‘01947
Apparent Expansion . .ecccseseseesees “O1526

Expansion of black-lead........+6.. "00421

Exp. 5. The same register of the fine-grained black-lead
was exposed for a quarter of an hour with the iron bar to
boiling mercury: the arc measured on the scale was 2° 49!
= expansion ‘02457.

Absolute expansion as before......... °02914
Apparent expansion ...ccccerescesesseee “02457

Expansion of black-lead........0+.0+0. *00457

Fine-grained black-lead by platinum ‘00421
by iron...... ‘00457

Mean... °00439

the two experiments differing from the mean by less than
ze%saodths of aninch. This shows that the fine-grained ware
expands less than the coarser, and proves the necessity of
ascertaining the expansion of each register for itself by boiling
in mercury; at least till some means be taken to insure their
uniform composition. Every register should also be marked
with a reference to its proper expansion; and I would recom-
mend all those who may use the instrument for delicate re-
searches, to verify this point for themselves; as they may easily

do with the apparatus before described.
Exp. 6. The expansion of the last specimen of black-lead
ware

Sor Measuring the Expansions of Solids, &c. - 275

ware being nearly the least which has fallen under my obser-
vation, I repeated with it the experiment of the dilatation of six
of the former list of metals to the boiling point of water; as
the accuracy of these observations is a point which it is of the
greatest importance to establish.

The subjoined Table contains the results.

Taste VIII.
Platinum... 0°22’ = :00319 from 60° to 212°

Tron ...e006.. O 39 = *00566
Copper...... 0 54 = ‘00785
Brass ....s06. O 59 = *00857 Seana
Gold.........5 O 41 = °00595
Silver. ...... 0 58 = ‘00843

The differences of the observed expansions and the real are
also subjoined and ranged by the side of those obtained by
the first series of observations.

Taste IX.
i Expansion of the Metal Bars. Expansion of Black-lead. :
Platinum absolute -00478 Second Series. First Series.

Differ. from Differ. from

apparent °00319 Mean. Mean.
=00159 + -00000 ... -00202 —-00032

Iron ...... absolute -00640
apparent -00566

=:00074 —-00085 ... -00132 —-00102
Copper ...absolute -00930

apparent -00785
=00145 —-00014 ... -00247 +-00013

Brass..... absolute -01045
apparent -00857

Gold...... absolute -00794
apparent -00595

—- =00199 +-00040 ... -00242 +-00008
Silver ..... absolute -01034
apparent -00843

—— =-00191 +-00032 ... -00220 —-00014

Mean -00159 ....... sddotcevisess -. 00234

The agreement of this second series with each other is quite
as close as that of the first; and it is worthy of remark, that
the greatest variation from the mean is in both cases with the
iron in deficiency, and nearly to the same amount of one half.
It is not unlikely, therefore, that there may be some error in
estimating the abvoliite dilatation of this metal, which is pro-
bably something greater than we have assumed.

If we estimate the expansion for these 150° to the boiling
point of water from the result obtained by the boiling of mer-
cury, we shall have the following proportion :—

596° : 00439 :: 150°: 00110
2N2 which

=:00188 +-00029 ... -00246 +-00012

276 Mr. Daniell on a New Register-Pyrometer,

which does not differ quite ;>5,59dths of an inch from the
foregoing mean.

Having thus, I trust satisfactorily, established the accuracy
of the pyrometer, and the degree to which confidence may
be placed in its indications, I shall conclude this part of my
subject with the details of some experiments upon the fusing
points of different metals. I shall designate the registers of
coarse and fine-grained black-lead respectively by the letters
A and B.

Exp. 7. About 30lbs. of the clippings of thin sheet copper
were very gradually melted in a crucible in the blast furnace
of the Royal Institution. The platinum bar was adjusted in
the register B, and when the metal was about half run down,
it was placed perpendicularly with the index upwards in the
crucible, and held down with a pair of tongs. The crucible
was then gradually fed with the clippings till the melted metal
covered about two-thirds of the register. In this situation it
was kept ten minutes, and when it was lifted out some of
the metal remained unmelted. A crust of oxide, mixed with
metal, had also affixed itself to the upper part of the black-
lead. This was partially dissolved away and loosened by im-
mersing the register with great care, when cold, in a diluted
mixture of sulphuric and nitric acids. ‘The whole was thus
easily removed, and the black-lead exhibited a perfectly clean
surface. The arc measured upon the scale was 5° 49', de-
noting an expansion of *0508. The temperature of the labo-
ratory was about 65°.

I am indebted to the kindness of Mr. Mathison for unex-
ceptionable opportunities of taking the melting points of gold
and silver at the Royal Mint, who also most obligingly assisted
me in the operations. Two new registers were prepared, which
I shall designate as II. and III.: their rates of expansion
were not determined till after the experiments.

Exp. 8. The register I]. was carefully adjusted with the
platinum bar. About 90lbs. of fine gold were weighed, and one
of the ingots was cut into ten pieces for the purpose of gra-
dually feeding the crucible, and keeping the temperature down
to the true melting point during the observation. The re-
mainder was melted in a black-lead crucible in a wind-furnace.
When just fused, one of the pieces was thrown in, and the
melted metal immediately congealed upon the surface. The
register, which had been slowly heated in another crucible to
a dull red, was then taken up with a pair of tongs and plunged
perpendicularly into the gold about two-thirds of its height.
In this situation it was kept ten minutes, and during the time
two more lumps of the metal were thrown in. It was then

carefully

Sor Measuring the Expansions of Solids, &c. 277

carefully lifted out and set apart to cool. Its surface was per-
fectly clean, only a few small globules adhering to it, which
were easily removed. I may here remark, that stirrers of the
black-lead earthenware are constantly used at the Mint for
agitating the melted gold. The arc measured from this ex-
periment was 6° 10!, equivalent to an expansion of -0537.
Temperature of the air about 65°.

Exp. 9. The register III. was fitted with the iron bar, and
also heated to a dull red. The temperature of the melted
gold was prevented from rising by constant feeding with the
pieces; the crucible being never left without some portion
unmelted. It was then plunged beneath the surface of the
metal as in the preceding experiment, and held in that situa-
tion for ten minutes. ‘The arc measured was 9° 2', indicating
an expansion of ‘0787.

Exp. 10. The rates of expansion of the two last registers
were determined by boiling them for ten minutes each in
mercury. ‘The results were as follow:

Arc. Expansion.
II. with the platinum bar ...... 19°50 = °0159

III. with the iron bar .........00. 2°38 = *0229

Exp.11. About 50lbs. of pure silver were melted in a black-
lead pot: a little scum floated upon the surface, which ap-
peared at first like drops of oil upon a basin of water. I was
afterwards informed that the metal had been refined with nitre,
and the dross was owing to the action of a little remaining
potash upon the crucible. Two registers had been prepared
for the platinum and iron bars; but the observations were
lost from the same action upon their substance. They were so
deeply corroded in a line which corresponded with the level
of the fluid metal, as to render it impossible to apply the scale,
with any certainty, to their surfaces.

Exp. 12. Two new registers were selected, whose rate of
expansion was found by boiling in mercury to be equal; the
arc in both cases being with the platinum bar 1° 20/ = -0116.
They were marked IV. and V.

IV. was adjusted with the platinum bar. An ingot of silver,
which had been refined by cupellation, weighing about 35lbs.,
was placed in a black-lead crucible in a wind-furnace. When
somewhat more than three-fourths were melted, the register,
previously heated to a dull red, was plunged into it as before,
and held down for ten minutes. When lifted out, its surface
was found perfectly good, and the few adhering globules of
metal were easily removed. When cool, the scale was applied,
and the are found to be 4° 10' = expansion ‘0363. ‘Tem-
perature of the air 65°.

Exp. 13.

278 Mr. Daniell on a New Register-Pyrometer.

Exp. 13. The iron bar was placed in the register V., and
having been previously heated was plunged into the same pot
of metal. The silver at first set about the black-lead and ad-
hered to it in a large lump. At the expiration of ten minutes
this was just melted off, and the instrument was raised out of
the crucible in a perfectly clean state. When cool, the arc
measured was 7° 24' = expansion °0645.

Exp. 14. I made several attempts at the Royal Institution
to ascertain the melting point of cast iron; but owing to the
large quantity of the metal necessary; to the difficulty of
keeping the temperature steady by constant feeding; and to
the failure of crucibles,—I did not succeed. I am under obli-
gation to Mr. Parker of Argyle-street, for the readiness with
which he afforded me every facility of performing the experi-
ment at his foundry.

I selected a new register for the occasion, which was
marked I. Its rate of expansion was not determined till after
the experiment. A crucible was prepared capable of con-
taining about 35lbs. of the metal. It was filled with pieces of
the best gray iron, and placed in a powerful wind-furnace,
which admitted of the operator standing immediately above
the crucible with complete command over it. When the metal
was melted, the crucible was lifted from the furnace, and the
dross skimmed off its surface. It was then replaced; a lump
of the same iron was thrown into it, and the register, pre-
viously heated red hot, was immersed in the fluid to about the
same depth as in the former experiments. It was kept in this
situation by means of a pair of tongs for ten minutes, and after-
wards gently lifted out and laid upon hot sand. A thin scale
of iron adhered to the black-lead, which when cold was easily
removed, and retained the form of the bar like a sharp cast,
and left the surface of the register perfectly clean and bright.
The arc measured after the experiment was 6° 16! = expan-
sion 0546. Part of the lump of metal remained unmelted.

Exp.15. Another register, which had been prepared with
the iron bar, was immediately immersed in the fluid metal.
The fire, however, had been allowed to fall, and the iron al-
most instantly congealed ; and in attempting to lift the register
out, it was found to be set fast and broke. ‘The experiment
was so far instructive, that it proved how nearly the exact
melting point had been attained in the preceding experiment.
The iron bar was removed uninjured.

Exp. 16. The register I. with the platinum bar was boiled
in mercury for ten minutes: the arc afterwards measured was
1° 20/ = expansion ‘0116.

Exp. 17. About 30lbs. of zinc were carefully melted in a

crucible

On the Calculation of the Orbits of Double Stars. 279

crucible set in a common fire, assisted with the bellows.
The register A was prepared with the iron bar and held down
in the metal, which was supplied from time to time so as to
insure its very gradual fusion, and some portion always re-
maining in the solid state. In ten minutes time it was re-
moved, and when cold the arc measured was 2° 45', equivalent
to an expansion of :0239.

A dry stick of deal plunged into the melted metal for a few
seconds caused a violent ebullition, and was deeply charred.
The zinc in this state did not appear red in the light.

Exp. 18. About 12lbs. of zinc were melted in a smaller
crucible: the register B prepared with the iron bar was im-
mersed in it; but instead of being gradually supplied, the heat
was allowed to increase after fusion till it began to burn: at
this point there was an evident blush of red upon its surface.
The arc measured upon this occasion was 4° 7! = expansion

0358.
[To be continued. ]

XXXVI. On the Calculation of the Orbits of Double Stars.
By Professor Encke.

[Continued from vol. ix. page 410.]

N making the corrections for the purpose of fulfilling the
equations of condition, one may be guided by the conside-
dp

ration that k = ¢ Fp = constant.

If, therefore, several p have been observed at intervals of time
not too great, but likewise not too small, so that we may put,
approximately, oP in place of ae and if the distances ap-

pear to be more certain at one epoch than at another, one
may correct the distances at the other epoch, having
9191 ree = 92 g, Pe
1 2
We have already observed, that the angles of position appear
to be capable of a more accurate determination than the di-
stances. On account of the uncertainty of the observations of
the angles of position, it will not be advisable to take A ¢ too
small. As soon as one is pretty near the truth, and a rough
drawing will, in most cases, lead us so far, these trials appear
to be most adequate to the purpose on account of the simple
form of the equation. In the beginning it will, however, be
necessary

280 Prof. Encke on the Calculation

necessary to change « more frequently than is desirable, as
ae = 4 sin 2°) will exceed 1 when z exceeds 30°.

This calculation may, however, be abbreviated, as the cal-
culation of ab may be saved by immediately substituting the
values of (15) in the equations (16). Combining the value of
a b with one of the equations (16) in which the same differences
of the excentric anomalies occur,—for instance, the third equa-
tion (15) with the first (16),—we obtain

MP vie __ (1234) tang 2 ¢ tang Z 2(B—a)— sin 2 (B—a) 1
k(ty 4) (0 1 2) = tang 22, ~~ sin (B—a)? sin 2y
consequently in every equation we shall have a function of this
form : eye Qn —sin2z

hdd a 4 sin a
whose value may be given in a table.
The function may be reduced to the following form:

x (2)

= i2(1+ cotang z*)—4 cotang x
= $2 + 4(xcotang x—1) cotang z
We have now, if A, B,C stand for the numbers of Ber-
noulli, viz.
A=7,B= 7 C= 7 &c,
these equations :
9%

— pee
1234” C

gs

a See eee
123456"

_ 2 2
z cotang c—-1 = —A>>2°—B

22

dll fe 3 2° 5
cotang s =— —A 7 7-Bi54" Cae Be as

Having due regard to the following relations:

Be; oe 1234 ° 9
we obtain for (x cotang x—1) cotang ~ this series:

A eatt Bi pes eto hal
and

pa 2 3 2 5 Ce
x(z)=—=- Art Tag Br + Tange C2i+ ieee Da". os
By this series the value of the function may be easily calcu-
lated for small values of x; for greater ones the finite ex-
pression is accurate enough for calculation. The limit of the
conver-

of the Orbits of Double Stars. 281

convergency of the series may be most easily investigated by
introducing instead of A, B, C, &c. the sums of the reciprocal
even powers of numbers; if

1 1
+ 3 a Ae eeccece

1
alt ge
1 1 1
sr ih 6 lic IRA eccene
1 1 1
oe

e=1+ Bea tig aaah fe ts

it is well known that

n= a2 ™

Ea NPE |
2B y

e 1234 ”
2°C .

= —————. 7
123456

consequently,
Qa « 4b & G6e 2 8d 2
AO) iT Sei lV NMM ib gM THATS

In the distant terms of the series the ratio of two successive

powers of <, say 23 ey and ca Winker ee

coefficients let be represented thus :
2h, and PP eg
T us
will more and more approach to unity, so that the series will
always. converge for z<a. Making « = 47 we have x (37)
= 47, consequently
By 20. «Be... ea 5e
NO ET ALE: AE RRS Rinne
Within the limits x = 0 and « =17, the change of this
latter function is only the fourth part of that of the quantity
2a—sinZ«. This change may, however, be still more di-
minished, and the transcendental function to be introduced
may be made still more like a constant quantity by combining
it with a divisor by which the first power is made to disap-
‘ : 2xe—sin2xr
pear. If we choose sin « for this purpose, we have or
exactly the same quantity employed by Gauss in his Theoria
Motus, for solving the problem of determining the elements
N.S. Vol. 10. No, 58. Oct. 1831. 2 from

282 Prof. Encke on the Calculation

from two radii vectores, and the inclosed angle. This quantity
changes between x = 0 and x = 37 from 3 to 37; and the
introduction of this quantity would have the additional ad-
vantage that, if two equations were combined, in which B—a
and 6 +a, or the other similar combinations occur, the ratio
of sin (8—a) and sin (@+«) is very simply represented by
equations (9). As this advantage, however, disappears in the
case of the other combinations, it appears more convenient to
use tables for the function :

Qxe—sin2x

sebghies 4. 2 Sin x?
93 95 gi
—| 9 — 2 SS " 4 x eceeee
A+ rag Be"+ raga5 C+ Tesa567 © :
for z = 0 the value of this quantity is = 4
HON = "OO. he eee eececawecovetcesccten eee

and for the intermediate values the changes are nearly con-
stant. A table for this expression has likewise been appended
atthe end. It gives the values for every ten minutes of 2;
and for the convenience of the calculation the logarithms of
the values of the function divided by the number of minutes
contained in the radius have been given, or

2a—sin2 x ]

(18) log 4 (e) = log | Saas * saa776 }

The value of 2 expressed in minutes of an arc will always
have to be combined with these values.

This function being introduced, and making
tang 2 ¢ watt
tang 2¢,
(19) (1234) =N,
tang 2 ¢, ae 8
tang 2%

the equations (16) will assume this form:

(1234)

(1234)

k(tg—t,) =N_ tangg re vy (B—a)+(012)

(tt) = Ny tang &, 22) y (y—a)+(018)

(20) k (ts—t2) = N, tang % =e) v(y—P)+ (02 3)

sin 2a

k (t,—t,) = Nacotangt, vari v (y +B) +(0 1 4)
k(t,—t,)

of the Orbits of Double Stars. 283

# (gt) = Nyeotang’ FA o (y +a) + (024)
k (t,—#3) = N cotang¢ nee b (B+a)+(0 3 4)

in all which, if the numbers of the tables are made use of, the
angles 8—« &c. are to be expressed in minutes of an arc.

In applying them the process will be nearly as follows.
The observed angles p &c. give a preliminary knowledge of
the values of «, 8, , which will be sufficient for taking the func-
tions ) (—«) &c. from the table so accurately that their sub-
sequent alterations will never be considerable, their values
for an interval of 90° being confined between 3 and 3.

Making next,

N tang iid (012) —
ra et ee Me A dy
N, tang & (01 3)
9 1 ol ed — —
(21) t,—t, vy ct) Sayles tz—t, ae d, 9
N, tang % a (023)
me v (y—B) = © » ey nei d,, Xe.
we obtain equations of this form:
_,, B=s
hi) sin 2 Sy He
(22) k= ¢ AE: + d,
EAI Sat ¢
ihe sin 2@ A hb

In the first approximation the quantities c, &c. are consi-
dered as accurately determined, and that value of «is sought,
which, with its corresponding 8 and y, will satisfy two equa-
tions. Trials will soon effect this purpose. By means of these
values the quantities c are corrected, and they will then be
obtained with an accuracy which hardly requires any further
correction. The new values of «, B, y, thence deduced are
now substituted in thethird independent equation, with the view
of ascertaining whether all observations belong to the same
ellipsis. Small differences are then corrected by an alteration
of the times. In the cases of greater differences the distances
for the less accurate observations must commonly be changed,
and then, indeed, the ¢¢, %,, and the areas of the triangles on
which they depend, must be found by a new calculation.

The formule (A), (B), (C), (6), (8), and (20), which only

202

are "

&

284 Mr. Nixon’s New Method of Levelling

are required, being so very simple, and the calculation being
more than sufficiently accurate if conducted with five decimal
places, the time required for the calculation is not very con-
siderable. If cases should occur in which observations only
for which x exceeds 90° could be combined, one might either
directly calculate the formula, or use this form:

tay _,\_. 90° , cotang

It appears to be most convenient to begin with trials of
assumed values of «. We have agreeably to the above-given
notation :

a = 7(E,—E,) — }(E,—E)).

It will easily be decided whether « is to be taken negative
or positive, whenever it differs considerably from 0. If there
is no semi-revolution between any two successive observations,
a will always be < 45°. The quantities B + a, y + #, being
by their nature always positive, and at the same time < 180°,
if the period of the observations does not embrace a whole
revolution the quadrants in which £ and vy are to be taken, are
consequently fully determined.

As soon as a, 8, y and then likewise a6 have been deter-
mined, only two of the equations (4) are required for deter-
mining a, b, and s, and for obtaining, consequently, the pro-
jected ellipsis in magnitude and position with regard to the
star at rest. If, however, we have been at the trouble, which
cannot well be dispensed with, of adapting all four observa-
tions to the same ellipsis, we may obtain these data more
easily by a symmetrical combination of the same.

{To be continued. ]

XXXVII. New Method of Levelling the Axis of a Transit
Instrument. By J. Nixon, Esq.*

| bs’ the subjoined figure, A is an achromatic object-glass,

firmly secured within one of the pivots of the hollow axis of
the transit instrument. a is a stop furnished with adjustable
cross lines placed within the other pivot exactly at the sidereal
focus of the object-glass A.

B is another object-glass fixed within the opposite pivot
having its corresponding stop and cross lines situate at 0.

D and E are two upright columns, each carrying a hori-
zontal bar to which a pair of Ys is fastened. These columns
might be attached to the Ys of the transit, but it would be
more prudent to fix them independent of it.

* Communicated by the Author. ;
C is

the Axis of a Ti vansit Instrument. 285

C is an achromatic telescope fitted up with adjustable cross
lines placed at the sidereal focus. It rests within the Ys
of the support D, or those of the support E, according as it

a)
(|

i Rem eg
(

(Se (SEES re PSS)

7 An
Ere gas
- ~~}
wil ee dake NA OD eid el ey
C s

=

|

is required to look with it through the object-glass A or B.
(A vertical slip of thin mother-of-pearl, having a well-defined
dot about the middle, would be better than cross-lines.)

The wires of the telescope C, and ‘those within the axis of
the transit, will require no other illumination than what is de-

rived

286 New Method of Levelling the Axis of a Transit Instrument.

rived from the transit lamp placed on the bar of the support
opposite the one in which the telescope C rests during an ob-
servation.

To make the mathematical axis (or line of rotation) of the
transit parallel to the horizon, the line of collimation of the
object-glass A, and afterwards that of B, must be rendered
parallel to the line of rotation, ‘This will be the case when
the line of collimation of the telescope C, placed against either
object-glass, preserves during a revolution of the axis of the
transit its parallelism to that of the object-glass to which it is
directed. The line of collimation of both object-glasses being
now parallel to the line of rotation, point the line of collimation
of the telescope C exactly at that of the object-glass A, and
note the level (g) attached to the former. ‘Then remove the
telescope to the Ys of the support E, and point it accurately
at the intersection of the cross lines of the object-glass B. In
the event of the line of rotation being horizontal, the bubble
will revert to its previous position; otherwise half the devia-
tion will be the inclination of the line of rotation.

As it may be difficult to make the line of collimation of the
object-glasses rigorously parallel to the line of rotation, the
telescope must be twice pointed at the object-glass; one ob-
servation taking place before, and the other after the axis of
the transit has described half a revolution. ‘The mean of the
two readings of the level will then be equivalent to one reading
with the cross lines perfectly adjusted.

In bringing the line of collimation of the telescope of the
transit to be at right angles to the line of rotation, the latter
must be levelled (after the method described) before as well as
after the axis is reversed ; otherwise, at least in the case of the
pivots being unequal in diameter, the adjustment cannot be
accurately effected.

When the line of collimation of each object-glass has been
rendered parallel to the line of rotation, and the telescope C
left correctly pointed at the cross lines of the adjacent object-
glass, take the axis of the transit instrument out of its Ys, and
replace it within them reversed in direction. The other ob-
ject-glass will now be brought nearest to the telescope C; and
should the line of collimation of the latter be found strictly
parallel to that of the object-glass, it will prove that the pivots
are of the same diameter.

Leeds, August 4, 1831. Joun Nixon.

Erratum.— Vol. ix. page 428, line 37, for the angular
opening of the Y, read half the angular, &c.

XXXVIII. No-

{ 287 ‘;

XXXVIII. Notices respecting New Books.

An Elementary Treatise on the Differential Calculus: comprehending
the complete Theory of Curve Surfaces and Curves of Double Cur-
vature. By J. R. Youne.

Ho” cursory soever be the survey we take of the present state
of physical science, we must be convinced how extensively
dependent it is upon the Differential and Integral Calculi, in some
or other of their varied modifications. So complete, indeed, is this
dependence, that he who attempts to pursue any one branch of
physical inquiry beyond its simplest and most elementary state, will
find his progress at once arrested, if he be not provided with this
apparatus of research: and those who have penetrated most pro-
foundly into the arcana of nature and of nature’s laws, have uni-
formly concurred in the statement—that the principal desiderata
are improved methods of effecting the mathematical processes to
which the individual inquiries give rise. Several branches of philo-
sophical investigation, indeed, seem to admit of no boundary, save
that which the imperfection of our mathematics impresses on them ;
and every improvement which the calculus receives is sure to open
new facts and new views, and often new paths of inquiry, which the
mere experimentalist could never have suspected. The time may
come, too, when sciences which as yet seem to acknowledge no dis-
coverable quantitative laws, and especially with respect to the modi-
fication in the intensities of the producing forces, shall offer a splen-
did triumph to human perseverance, and fall as completely under
the dominion of the symbolic methods, as the system of the celestial
motions in the writings of Laplace can exhibit in our own time. This
consummation is neither so visionary nor so remote as to discourage
our hopes or paralyse our exertions: it rather, on the contrary, ani-
mates us with redoubled assiduity, whilst it offers the most cheering
encouragements to future labourers. Already some gifted minds are
intent upon marking the probable boundaries, and the proper route
to be pursued ; others are penetrating the dense and tangled masses of
foliage, with which the baneful tree of error has overrun the soil,
and intercepted our view of the recesses of nature's works ;_ while
others again, more'humbly but not less usefully perhaps, stand at the
entrance to encourage the young adventurer, and to point out to him
the surest and the most successful route he can pursue. It falls to
the lot of few to open new paths; but every man of science may
more or less contribute to the ulterior object of all their exertion, and
facilitate the progress of the young philosopher by removing the ob-
stacles that would arrest his career. It is true, that in the capacity
of elementary writers or scientific lecturers, all men will not be alike
successful, whatever their actual attainments may be; for the peculiar
faculties of the mind are as much displayed in the composition of an
elementary book, in the verbal explanation of a process, or theillus-
tration of a principle, as in any higher order of intellectual exertion.
Higher, indeed, we have called it ; but we are not sure that there is
less loftiness of view, whilst we are certain that there is often much

more

288 Notices respecting New Books.

more logical clearness, displayed in a happy development of first
principles, than the subsequent investigation commonly exhibits, At
all events, it is a task in which there are more failures than are com-
mensurate with the difficulty ; except it be admitted that to produce a
good elementary book be an undertaking of a higher order than is

commonly supposed. In mathematical science this is peculiarly the ”

case ; and in that branch to which Mr. Young’s book is devoted, this
difficulty has been felt more strongly than, perhaps, in any other. The
universal complaints which we hear of the unintelligibility, not to say
inconclusiveness, of the processes and reasonings which stand at
the threshhold of the Differential Calculus, must convince us that
there is a radical defect somewhere, and stimulate our search for its
place and its essential character.

Is there too wide a chasm between the processes of common alge-
bra as now practised, and the elementary steps of the Calculus? Is
there something in the leading notions which the science involves,
which too greatly transcends the superficial conceptions of the undis-
ciplined mind ? or, finally, is there something in the doctrine itself
repugnant to the conclusions which the ancient geometry, or the
scarcely less satisfactory reasonings of the algebraic analysis has fur-
nished examples of ? With respect to its compatibility with the vulgar
conclusions of ‘‘ common sense,” we might reply,—that the faculties
of uneducated mind take cognizance only of general appearances
of similarity, and neglect the more recondite differences, as wellas the
more recondite agreements that may subsist amongst the objects of
its occasional contemplation ; and therefore that its decisions are
valueless on topics foreign to those it is conversant with, and even on
its most familiar topics viewed under a novel aspect. To penetrate
further than this, we must do more than perceive the individual facts,
—we must class them, and reason on their appearances. This is
the first step in science. To do this, however, we must make a vi-
gorous effort to dethrone the host of prejudices which have usurped
the place of reason, for it is no easy matter to reject the hasty gene-
ralizations of common sense, which, being acquired during the vague-
ness of early and desultory speculations, are almost always ranged
on the side of error. Those processes of algebra, too, which are com-
monly studied prior to entering upon the Calculus, are too often mo-
dified to meet some fanciful or pertinacious objections of the man of
mere common sense, rather than framed as an introduction to the
kind of thinking which this science involves. It is presented as the
end, rather than the beginning of mathematical science. Such a pro-
cedure might have been well adapted to Goldsmith’s ‘‘ loveliest village
of the plain,” and its interesting pedagogue ; but as the first step
towards those profound inquiries which characterize the physics of
the present day, it is impossible to imagine how works could he
worse adapted than our common treatises on algebra. This is the
source of much of the difficulty that is felt in laying down the princi-
ples of the Differential Calculus ; and considerable dexterity is re-
quired to enable the preceptor to lead his pupil to frame even a tole-
rable conception of the character of the science, Still this is not the

only

i -

Notices respecting New Books. 289

only source; for after all, there is much vagueness (even amongst
those who have become considerable adepts in the practice of the
Calculus) in the reasons which are commonly offered for the validity
of its processes. This vagueness is displayed in the preliminary steps
of the inquiry in a striking degree. Amongst mathematicians of
considerable eminence, we shall find confusion and contradiction pre-
vail, as to the fundamental axioms, the fundamental definitions, and
the fundamental reasonings of the science: and it almost invariably
happens that the student acquires considerable practical dexterity long
before he is able to unravel the mysteries of prime and ultimate ratios,
of fluxions or rates of increase, or any of the other principles which have
been made the basis of the method. If he have courage to persevere
(more as acalculator than a metaphysician) till he can learn the method
of operating ;—if he can solve a few problems by means of the Calcu-
lus thus acquired ; and if in addition he can verify these results by an
appeal to some geometrical properties already known ; then he learns,
and thus he learns, by degrees, to feel confidence in the power and
accuracy of his rules. He infers that because it gives right results in
the cases he has tested, it therefore will in all. Yet why it should
give right results in any one case, he cannot make out in any plausible
manner: and, indeed, the vagueness and confusion which he expe-
rienced at the outset, when he attempted to master the reasons, dis-
couraged and disgusted him too much to render it an agreeable un-
dertaking to attempt the investigation anew. He thus willingly takes
it upon trust, or on the authority which belongs to mere induction,
instead of laying a broad and satisfactory basis upon a course of in-
disputable logical demonstrations. It is a painful fact,—but there is
reason to fear that it is the case of nine mathematicians out of ten,—
that they have no clear view of the first principles of the Differential
Calculus, however expert they generally are in the application of its
rules to the solution of problems: and it is in consequence of this
painful fact, that we hail with pleasure the little work of Mr. Young,
as a panacea, in some degree, for the evil we complain of. It is
of the utmost importance that the young student should be inspired
‘with clear views of the nature of the relations contemplated in the
science: that his mind should be put in attitude to perceive the force
of the reasoning—and that the ulterior objects of the Calculus should
open upon his understanding with the utmost possible distinctness. This
can only be effected by an author deeply in love with truth, and whose
mind is enlarged by an extended survey of the subject upon which he
writes ;—an author who conducts his inquiries and develops his
conceptions with due regard to method, and who is, moreover, en-
dowed with a happy elegance of diction ;—such a writer will not alter
what has already been done well, for the mere purpose of differing
from others, but will avail himself of the labours of his predecessors so
far as they contribute to the great object he has in view. Yet he will
always throw them aside when they are defective, illogical, irrelevant,
or unnecessarily operose ; and so modify them, where they admit of
modification, as to alter the visual appearance, or even the received
and familiarized phraseology, as little as is compatible with a clear and
N.S. Vol. 10. No. 58. Oct. 1831. 2P _ perspicuous

290 Notices respecting New Books.

perspicuous detail of the logic of the science, and the practice of the
art. This is precisely the purpose by which Mr. Young seems to have
been directed, There are no affected changes of method: there is
no parade of original plan, or of novelty of principle ; and yet there
is much original matter, much original reasoning, and, what is of
more value than all questions about originality in an elementary
treatise, there is a perspicuity, a unity of method, prevailing in all
its parts, that renders it, more than any book we have seen, peculiarly
adapted to instruction. It is professedly composed ‘for the Use of
Students in Schools and Universities ;” and we think the science is
brought more nearly to the level of school-boy capacities, than any
work we have consulted brings it to the understanding of a University
two-year man. We are persuaded that with due attention to the
steps of explanation and demonstration, any student with ordinary
powers of mind, and tolerably familiar with elementary algebra, may
master the difficulties of the Differential Calculus by means of this
work with very great facility ; and this once effected, he will proceed
to its diversified applications with a success that can never attend
the labours of those who take first principles upon trust, and lean
for the truth of the processes themselves, upon the authority of an
imperfect evidence.

It is not, however, as an elegant and perspicucus development of
the first principles of the Calculus, merely, that we have admired,
and therefore recommended, Mr. Young’s little work: we have found
much to commend in it of a more profound character; much that we
look for in vain in larger works, and indeed, in all English works.

We have already occupied so much of the room that we can devote
to this notice, that we cannot possibly enter into particulars; and,
indeed, we have greatly exceeded the limits of our plan, so that no
apology will be expected from us if we refer those readers who are in-
terested in this branch of mathematics, to the book itself, rather than
transcribe it into our pages. We feel, however, that we should appear
too abrupt to our readers and unjust to Mr. Young in closing without
noticing one or two of his chapters. One is the discussion of the
failing cases of Taylor's theorem (p.98.): a chapter which offers a
fair specimen of that happy facility in the discussion of an intricate
and embarrassing question, which pervades the work, and which we
think marks the perfection of didactic writing. This theorem, the mere
accidental notice of which has conferred immortality on its author, is
made the basis of almost all those mathematical processes employed in
physical inquiry which in any way involve the Differential Calculus ;
and it has been aptly denominated by the late lamented namesake of
the gentleman whose work we have now under review, (Dr. Thomas
Young,) ‘a universal Solvent of Analytical difficulties.” Whether
this appellation be too strong or not, we shall not here inquire; but
it has long been known, that as a general expression, it is subject to
some limitations in its application. The knowledge that such limita-
tions did exist, and our ignorance of any test by which their presence
might be recognised, has long rendered the settlement of this ques-
tion a matter of anxious interest to the mathematician and philoso-

pher.

Notices respecting New Books. 291

pher. Many explications and discussions have appeared at different
times, more or less converging towards a correct theory of these
cases ; and we think the doctrine may be called complete as it ap-
pears in the work of Mr. Young *. :

The doctrine of curves and curve surfaces is also developed with a
neatness and elegance which we do not recollect to have seen in any
English work ; and though Mr. Young refers to Monge and Leroy as
the authors whom he has principally had in view as models, yet upon
looking into the work of the latter, we remark several great improve-
ments in the execution; and as to that of the former, the portions which
it could contribute to any elementary work are necessarily very few.
We were particularly pleased with the demonstrations of the theo-
rems of Euler and Meusnier upon the curvatures of surfaces, and with
the somewhat novel way in which the evolutes of curves of double
curvature are explained (p. 224.). Regard, however, must be had
to alittle correction on p. 225, as supplied in the Errata. We have
remarked a few typographical errors in other parts of the work which
it would be well to annex to the list already given, and which we
hope the publisher willdo. The paralogisms of some other writers,
—distinguished ones too—are pointed out in the Preface, and in the
body of the work; and many steps which have hitherto been deemed
unquestionable, have been shown by Mr. Young to be altogether
fallacious. We wonder, indeed, when wesee them pointed out, why
they did not occur to ourselves nor to anybody else till now ; and
we look upon the aptitude displayed in these detections to be highly
characteristic of a mind which looks with a laudable anxiety to the
purity of the fundamental principles of science.

The advantages furnished by the Syndics of the Cambridge Univer-
sity press in bringing out mathematical books, amounts almost to a
monopoly; and the general prepossession of the public in favour of
Cambridge men actually completes that monopoly, and shuts the
door against all competition from mathematicians less advantageously
situatedt. Taking all circumstances into account, we doubt whe-

ther

* We would suggest to Mr. Y. that the remark at p. 106, needs no qua-
lification, the same remaining true from h= 0 toh =a, both inclusive ;
for when # = a, although the expression becomes then

eset Wa etic Shai:
it nevertheless continues true, because all the imaginaries on the right side
will destroy each other.

Mr. Young has established, too, that when negative powers of / enter
into the development, the terms which precede the first such power of h,
is the true expansion: and it seems, we would hint, to depend on the same
principle, viz. that all the infinites neutralize each other.

+ “It is very easy to account for the appearance of more mathematical
publications from Cambridge,” says Dr. Abram Robertson, “ than from any
other place in this kingdom. The members of that University, who persevere
in the study of science, and who are conscious of their ability either to
elucidate its truths, or enlarge its boundaries, can look with confidence to
the syndics of the press for assistance, to render their writings profitable to
themselves, and useful to the public. All apprehension as to the pecuniary

2P2 risk

292 Notices respecting New Books.

ther the well-intended attempt of the founders of those funds to
encourage the publication of valuable books has not been indirectly
the cause of much injury to science, by shutting out from the contest
all but a privileged body of competitors. It is like a statesman who
shall offer a bounty to one manufacturer and refuse it to another : it
is easy to see the consequences of the latter, and draw the parallel
between the two cases. And its ill effect has been greatly aggra-
vated by the enormous tax on paper, from which the University en-
dowed presses enjoy an exclusive exemption, and the duty on adver-
tisements, by means of which alone, an unknown or unpatronized
author can bring his works before the public. We are led to make this
remark by the following strain of just complaint in which the talented
author, whose work has formed the subject of the preceding remarks,
concludes his Preface, and with which we shall conclude our present
notice.

«<T am not, however, so sanguine as to look for much public en-
couragement of my labours, however successfully they may have been
devoted: it is not customary to place much value, in this country,
upon any mathematical production, of whatever merit, that does not
emanate from Cambridge. The hereditary reputation enjoyed by
this University, and bequeathed to it by the genius of Barrow, of
Newton, and of Cotes, seems to have endowed it with such strong
claims on the public attention and respect, that everything it puts
forth is always received as the best of its kind. If this be the case
with Cambridge books, of course it is also the case with Cambridge
men, and accordingly we find almost all our public mathematical si-
tuations filled by members of this University. It is true that now
and then, in the course of half a century, we find an exception to
this; one or two instances on record have undoubtedly occurred,
where it has been, by some means or other, discovered that men who
had never seen Cambridge knew a little of mathematics, as in the
case of Thomas Simpson, and of Dr. Hutton; but such instances are
rare. Itis not for me to inquire into the justice of this exclusive sy-
stem; but, while such a system prevails, there need be little wonder
at the decline of science in England: while all inducement to culti-
vate science is thus confined to a particular set of men, no wonder
that its votaries are few. It is to be hoped, however, that in the pre-
sent ‘liberal and enlightened age,’ such a state of things will not
long continue, and that even the poor and unfriended student may be
cheered up, amidst all the obstacles that surround him, in the labo-
rious and difficult, but sublime and elevating career on which he has
entered, by a well-founded assurance that his exertions, if successful,

risk of printing is removed ; and those who write with a view to publish are
at once stimulated by the laudable desire of fame, and animated by the hope
of a fair and honourable recompense for their labour in the sale of their
productions. In other places, mathematicians may be equally successful in
their attainments, and authors of treatises as worthy of public attention ; but a
wish to present them to the world is checked by the deterring consideration of
an immediate and serious expense, and an uncertain and slow indemnification.”

—Reply to a Monthly and Critical Reviewer, p. 39.
will

Royal Society. 293

will not be the less appreciated because they were solitary and unas-
sisted.”

XXXIX. Proceedings of Learned Societies.

ROYAL SOCIETY.

June Aah, PAPER was read, entitled, ‘“ A critical and ex-

& perimental Inquiry into the Relations subsisting
between Nerve and Muscle.” By Wm. Charles Henry, M.D., Phy-
sician to the Manchester Royal Infirmary. Communicated by Wm.
Henry, M.D., F.R.S.

It has long been a subject of controversy among physiologists
whether muscular contraction is the immediate consequence of the
action of a stimulus on the muscular fibre, or whether it is neces-
sarily dependent on a change taking place in the nerve distributed
to the muscle, and excited by the stimulus, This question, the
author observes, is one which, from its very nature, is incapable of
a direct solution, because the intimate connection of nervous fibres
with every part of the muscles renders it impossible to distinguish
on which of these classes of textures the impression of the stimulus
is primarily made. The continuance of the motions of the heart
after the destruction of the brain and spinal cord, and even after the
entire removal of the heart from the body, has been adduced as
an argument of the independence of the contractile property of the
muscular fibre: but this argument the author considers as incon-
clusive, because the nervous fibres remaining in the heart, and
expanded on the interior of its cavities, may still be capable of per-
forming their usual functions, and act as the medium of excitation
to the muscular fibres : an hypothesis strongly supported by the
analogy of the voluntary muscles, which, though usually excited to
action by changes taking place in the central portions of the ner-
vous system, may yet, when removed from this influence, be made
to contract by irritations applied to the trunks of the nerves that
supply them.

As narcotic poisons act exclusively upon the nervous system, the
author conceived that uhey might afford the means of eliminating
the action of the nerves, and thus enable us to discover what share
they contribute towards muscular contraction. On applying the
empyreumatic oil of tobacco, or the hydrocyanic acid, to the sciatic
nerves of a rabbit, he found that the functions of that part of the
nerve which was in contact with the poison were destroyed, and that
irritations applied to that part no longer excited contractions in the
muscles. But when the portion which had been so affected was
cut off, and the galvanic wire applied to that extremity of the nerves
which remained attached to the muscle, contractions were produced.
Similar results were obtained when the poison was applied directly
to the brain. When, on the other hand, the poison was applied
to mucous surfaces so as rapidly to extinguish life, the muscles
throughout the whole body were paralysed, and lost all capability of
being excited to contraction.

The

294 Royal Society.

The inefficacy of opium applied to the cardiac nerves in arresting
the motions of the heart has often been alleged as a proof that those
motions are independent of the nerves. But the author found on
trial that a solution of opium injected into the cavities of the heart,
or introduced into the intestine, immediately arrested the muscular
actions of these organs. :

These phenomena appear to the author to accord best with the
hypothesis that the immediate antecedent of the contractions of the
muscular fibre is a change in the ultimate nervous filament distri-
buted to that fibre.

A paper was read, entitled, «« Experiments on the Length of the
Seconds’ Pendulum; made at the Royal Observatory at Greenwich.
By Captain Edward Sabine, of the Royal Regiment of Artillery,
F.R.S.

The experiments described in this paper were made with the
original convertible pendulum constructed by Capt. Kater, and em-
ployed by the author in Portland Place, in the year 1817; except that
the tail pieces were removed, and the moveable weight dispensed
with: and they were made on the vacuum apparatus established in
the south-west angle of the Pendulum-room, the place assigned for
it by the Astronomer Royal. Having had reason to suspect that the
retardation of the vibrations of the pendulum performed in circular
arcs, when the weight was above, was greater than that assigned by
the formula commonly employed, the author first investigates the
correction necessary to be applied from this cause. He next as-
certains the reduction to a vacuum for the small residue of air
which the apparatus still contained, or for the small portion which
may have introduced itself by leakage. ‘The alteration of rate for
each degree of Fahrenheit is then determined to be 0.441, a quan-
tity almost exactly the same as that which was deduced from a
former inquiry. The result of the present inquiry is, that the vibra-
tions of Captain Kater’s pendulum, which at 57° were found to be
86069.1 are at 62°, 86066.9. At this latter temperature, the length
of the seconds pendulum, in vacuo, would be 39.13734 inches.
Tabular details of the experiments accompany the paper.

A paper was read, “On recrossed Vision ; being the Description
of adistinct Tribe of ocular Phenomena, supplementary to a Ra-
tionale of the Laws of Cerebral Vision, recently published.” By
John Fearn, Esq. Communicated by Captain John Grover, F.R.S,

The phenomena described in this paper, and which the author
designates those of recrossed vision, are cases in which objects placed
between and very near the eye, such as the two sides of the nose,
appear on opposite sides of the sphere of vision: the object.on the
right side of the nose being seen to the left by the right eye, and
that which is on the left of the nose being seen to the right by the
left eye. These and other phenomena illustrative of the well-known
law by which we estimate the position of objects with relation to
the eye to be in a line drawn from its image in the retina through
the centre of the eye, are considered by the author as requiring
further explanation. Not satisfied with the theory of Berkeley, that

the

Royal Society. 295

the mind is guided by the perceptions received from the sense of
touch, in interpreting the signs furnished us by the sight, the author
proposes to explain these phenomena by an hypothesis of his own,
which he states in the following words. ‘‘ Over and above the gift
of two external or cranial eyes, man has been by his adorable
Creator endowed with an internal cerebral organ, which performs
the office o¥ a third eye, by being the common recipient of impres-
sions propagated either from one, or both of the external eyes; and
the mind, in her chamber of percipience, steers with regard to ex-
ternal objects by the same principle on which the mariner steers by
his compass. Thus the two cranial eyes are analogous, in principle
and situation, to two magnetic compasses placed upon a ship's deck;
while the third, or cerebral eye, corresponds to another compass
placed in the cabin below ; and the mind, situated like the captain-
mariner in his cabin, knows, from consulting the cerebral eye, on
what point of direction the body is steering ; although the mind no
more perceives either any external object, nor yet any image in the
cranial eye, than the mariner perceives (even in the vulgar sense
of the word perceiving ) the far-off land, or haven, towards which he
is surely making his way.”

A paper was read, “On the Thermostat or Heat Governor, a
self-acting physical Apparatus for regulating Temperature ;” con-
structed by Andrew Ure, M.D., F.R.S.

The principle of the instrument here described is the unequal
expansion of different metals by heat. A bar of zinc, alloyed with
four or five per cent. of copper, and one of tin, about an inch in
breadth, one quarter of an inch thick, and two feet long, is firmly
and closely riveted along its face to the face of a similar bar of
steel of about one third in thickness. The product of the rigidity
and strength should be nearly the same, so that the texture of each
may pretty equally resist the strains of flexure. Twelve such com-
pound bars are united in pairs by a hinge joint at each of their ends ;
having the zinc or alloy bars fronting one another. At ordinary
temperatures these bars will be parallel, and nearly in contact ; but
when heated, they bend ~utwards, receding from each other at their
middle parts, like two Jows tied together at their ends. When a
more considerable expansion is wanted, a series of such bars is laid
one over the other. The movement thus resulting is applied by the
author in various ways to regulate the opening of dampers, letting
in either cold air or cold water, or closing the draught of a fire-
place, as the case may be. He proposes its employment to regu-
late the safety valves of steam boilers, as working with more cer-
tainty than the common expedients.

A paper was read, “On the Determination of the Thickness of
solid Substances, not otherwise measurable, by Magnetic Devia-
tions.” By the Rev. William Scoresby, F.R.S. Lond. & Edin.
Corresponding Member of the Royal Academy of Sciences of Paris,
&e,

In the first part of this paper, the author states the results of a
series of experiments undertaken by him with the view of ascertain-

Ing

296 Royal Society.

ing whether all bodies are equally and uniformly permeable to the
magnetic influence. Out of a great number of substances not ferrugi-
nous, but of various qualities, thickness, and solidity, which were
subjected to trial, no instance occurred of their offering any per-
ceptible obstruction to the action of a magnet on a compass, when
interposed between them. No interruption to this action occurred
even when the intervening bodies were iron ores, of which several
were tried, excepting in one or two cases in which the ore was found
to be itself magnetic. Hence the author was led to conceive that
an accurate estimation of the magnetic influence transmitted through
solid substances, might afford an excellent mode of ascertaining the
thickness of such substances which might not be otherwise deter-
minable. In order to judge of the degree of accuracy with which
this might be accomplished, he instituted various sets of experi-
ments ; first placing the magnet in a line pointing to the centre of
the compass, and on a level with it, in the east and west magnetic
direction ; and secondly in positions more or less oblique to this di-
rection. He found reason to conclude from these trials, that the
degree of accuracy attainable by this method was such as to render
it highly advantageous in mining operations. Thus the thickness of
a mass of freestone rock on the Liverpool and Manchester rail-way,
three feet two inches in thickness, was determined by this method
to within the eighth of an inch of its actual measurement, exhibiting
an error of only one 334th part of the whole.

Many experiments were made to determine the effect which the
form, dimensions, quality, and number of magnets have on the ex-
tent of their directive influence on the compass. It was found that
little, ifany augmentation of power results from increasing the thick-
ness of the magnet ; but that, with magnets of similar form, the di-
rective forces are nearly in the direct ratio of their lengths. The
author gives the results of an extensive series of experiments on the
combined influence of several magnets, arranged, either in contact
or in juxta-position, in a great variety of ways. The contact of
dissimilar poles was in all cases productive of an increase, and that
of similar poles of a diminution of efficiency.

In the second part of this paper the author enters into an investi-
gation of the law of the magnetic directive power with reference to
distance: in which he finds it convenient to estimate all distances
in multiples of the length of the magnet employed, or, more cor-
rectly, of the interval between its two poles. From the established
law of magnetic force,—namely, that it is in the inverse duplicate ratio
of the distance,—the author deduces formule for estimating the di-
rective power of a magnet on a compass at different distances. The
combined action of four magnets, on a compass of Captain Kater’s
construction, which was five inches in diameter, will afford a tole-
rably accurate measurement of the thickness of any solid intervening
substance, when about forty feet thick ; but even at the distance of
eighty-two feet the deviation produced by the magnet will be two
minutes of a degree, and therefore still very appreciable. But the
sensibility of the compass to the magnetic influence might ria Sas

urther

Royal Society. 297

further increased, by the application of a small directing magnet,
placed in such a situation as to neutralize the greater part of the
directive influence of the earth. By this means the author obtained
a deviation in the compass of about 5‘, at a distance of 61 feet,
which extended through a variety of solid materials including soil,
stones, and brick-work.

In the third part of this paper the author treats of the practical
application of the magnetical influence in engineering, in tunneling,
and in mining, for determining the thickness of solid masses in dif-
ferent situations where circumstances preclude the possibility of
direct measurement. He adduces a variety of instances in which
the information thus obtained would prove of the greatest value, in
directing the operations in progress, or determining those to be un-
dertaken, and frequently in preventing the occurrence of accidents
which the want of such knowledge may occasion. He concludes
with a statement and explanation of various practical directions for
the employment of the method recommended.

A paper was read, ‘‘ On a new Register-Pyrometer for measuring
the Expansions of Solids.” Part II. By J. F. Daniell, Esq. F.R.S.,
Professor of Chemistry in King’s College, London.

In this paper, which is a sequel to that published in the Philoso-
phical Transactions for 1830, the author prosecutes the series of
experiments he had commenced on the dilatation of the metals :
pursuing the comparison between the results of the experiments of
Dulong and Petit, with those given by his own instrument. He
finds a striking accordance between them in the case of copper, as
he had already done with respect to iron and platina. He gives the
result of some trials which he made with a view to obtain registers
of uniform composition, so as to preclude the necessity of deter-
mining the rate of expansion in each individual instance. The re-
sults of his experiments on the dilatation of the metals are given in
tables ; the first showing in arcs of the scales the expansions of four
metals from 62° to 212°, and thence to 662° of Fahrenheit ; and
their respective melting points: and the second, exhibiting the ex-
pansion of certain alloys to the same points. The experiments on
the melting point of cast iron give a mean of 2768°, and present a
remarkable coincidence with the corrected temperature deduced
from the expansion of a platina bar, plunged into melted cast iron,
which was 2786° ; thus affording a conclusive proof of the accuracy
of the pyrometer, and of its competency to determine fixed and
comparable points of very high temperature. The author accord-
ingly thinks himself warranted in recommending the introduction
of the instrument extensively in all arts and manufactures, where it
is an object to regulate high temperatures, and where it is calcu-
lated to determine many questions of the highest importance both
to practical and theoretical science.

‘Two papers were read ; the one entitled, “ On the Influence of
Screens in arresting the Progress of Magnetic Action :"’ the other,
“On the Power of Masses of Iron to control the attractive Force of
a Magnet.” by William Snow Harris, Esq. F.R.S.

N.S. Vol. 10. No. 58. Oct. 1831. 2Q The

298 Royal Society.

The object of the first paper is to show that every substance
susceptible of magnetism by induction, when interposed as a screen,
tends to arrest the action of a magnet upon a third substance: this
intercepting power being directly as the mass and inversely as the
susceptibility to induced magnetism, Thus, although a single plate
of iron, about the sixteenth of an inch thick, effectually intercepts
the action of a revolving magnet on a disc of copper, the same re-
sult is not obtained when the disc acted upon is also of iron, instead
of being of copper ; unless the mass of iron interposed be very con-
siderable. The screening influence he found to depend on the mass
of iron that is interposed, and not on the surface merely. He was
led to suspect that a similar effect might be obtained by employing
substances not of a ferruginous nature, provided they were inter-
posed in considerable masses, and the result of his trials justified
his conjecture. An account is given of several experiments made
with large masses of silver, copper, or zinc, of about four inches in
thickness, which being interposed between a revolving magnetic
plate and a delicately suspended disc of tinned iron, completely in-
tercepted the action of the magnet on the iron.

The author considers this interceptive property to be more or
less common to every class of substance ; and that in order to render
it sensible, it is only necessary to employ the bodies in masses, bear-
ing some direct ratio to their respective magnetic energies. Thus
lead, having a weaker magnetic energy than copper, must be em-
ployed in a larger mass in order to produce an equal effect ; and to
render the screening power of ice sensible would require it to be
above thirty feet in thickness, If, instead of interposing the screen
of iron immediately between the revolving magnet and the sus-
pended disc of copper, the iron be brought very near the under
surface of the magnet, a similar neutralizing influence is exerted.

In the second paper, the investigation of this subject is resumed,
and the neutralizing power of a mass of iron investigated under
different circumstances. From the experiments detailed by the au-
thor, he is Jed toinfer that substances highly susceptible of receiving
transient magnetism, are the most efficient in their operation as
screens ; this operation being referrible to their neutralizing power.
It is, however, very difficult to render this power sensible in the case
of non-ferruginous bodies, unless they be actually placed between
the magnet and the substance acted upon, so as to neutralize effec-
tually the actions of those points which are nearest to each other.
The attractive force exerted between a magnet and a mass of iron
he finds to be always in the direct ratio of this controlling or screen-
ing power of the iron, or, in other words, to its neutralizing power
in similar circumstances,

The author suggests that a temporary magnetic state may be
conceived to be induced in a substance in two ways: either by the
immediate action of the magnet upon each individual particle of the
given substance, or else by the action of each particle of that sub-
stance on the next in succession, producing a propagation of ma
netism from the one to the other. It may also, however, take pla

Royal Society. 299

in both these ways at the same time. But these different modes of
action appear to be in some inverse ratio of each other: for when
the retentive or absorbing power of the substance is considerable,
the power of the magnet becomes soon controlled ; because the par-
ticles of the substance first acted upon, begin to operate as screens
to the succeeding ones, and the induced magnetism, after a certain
point, proceeds entirely by communication from particle to particle,
until the whole power is expended. When, on the contrary, the
retentive power of the given substance is small, little or no screen-
ing energy exists between its particles, in which case the magnetic
excitement will depend upon the influence of the magnet on each
individual particle: hence it is only by the succession or multipli-
cation of effect resulting from a great number of particles, that we
at length render the controlling power of such a substance sensible.
The diminished action of a magnet on a disc of copper, when inter-
sected by radiating grooves, seems to be owing to this cause, since
a portion of the substance, requisite to the full development of the
magnetic energy, is removed. In confirmation of this reasoning it
was found that the number of oscillations of a delicately suspended
bar, made in vacuo, in a given arc, surrounded by a mass of copper
formed into rings, did not sensibly differ when, in the one case, that
mass was made up of concentric rings, and, in the other, was eutirely
solid: while, on the contrary, by removing a very thin external
lamina from the former, the number of vibrations was sensibly
changed.

The concluding part of this paper is occupied by speculations on
the nature of magnetic action: the author being disposed to regard a
magnet as rather in a passive than an active state, when exhibiting
the phenomena of magnetic attraction. This attraction he con-
siders as the result of an impression first made on the magnet by the
iron which appears to be attracted by it: because he finds that with
different masses of iron of the same quality, the force at the same
distance is unequal; being with some pieces very sensible, whilst
with others it is altogether inappreciable. He views a magnet as a
substance put into a peculiar state or condition, in consequence of
which it exhibits certain properties when subjected to external ex-
citation ; in a way analogous to the elastic force of a spiral spring,
which is not called into action unless that spring is stretched by a
weight suspended to it, or by some other extraneous force. In the
case of magnetism, the exciting substance is likewise affected in a
similar manner with the magnet which it excites ; and the analogy
of the spiral spring may be further pursued, in order to render the
two cases corresponding, by supposing the weight which elongates
the first spring to be itself another similar spiral spring, which is
also elongated while exerting its force on the first. Under these
circumstances the separation of the coils will be greatest at the
upper end of the whole combination of springs, and least at the lower
part, presenting a contrariety of states at the two extremities, ana-
logous to the opposite polarities of the two ends of a magnet.

2Q2 A paper

300 Royal Society.

A paper was read, ‘On the Atmosphere of Mars.” By Sir James
South, F.R.S.

The author refers the origin of the hypothesis of the “Extensive
Atmosphere of Mars” to the observations of Cassini and Reener,
made at Briare and Paris in the year 1672. By the former it would
seem that a star of the fifth magnitude became invisible with a
three-feet telescope when at a distance of six minutes from the
planet ; whilst by the latter the same star, after having undergone
occultation by the planet, could not be perceived with a large tele-
scope till Mars had receded from it a distance equal to two thirds
of his own diameter ; although with the same instrument stars of
similar magnitude might be easily distinguished even when in con-
tact with the moon’s limb.

As opposed to these observations, the author advances his own.
One, dated Blackman-street, February 19, 1822, in which a star of
the ninth magnitude as seen with the five-feet equatorial suffered no
diminution of its apparent magnitude, at a distance of 103 seconds
from the planet. A second, on the night following, when the star
42 Leonis having been seen within a second of a degree of the
planet’s limb prior to occultation by the planet, was perceived after
emersion, when only one second and one tenth from it; the instru-
ments of observation in this instance were the five-feet equatorial and
the thirty-inch Gregorian reflector, the former instrument being used
by the author, the Jatter by Mr. Henry South, The third was made
at Campden Hill, on the 17th of March of the present year, with an
eight-feet achromatic of six inches aperture; and in this the star
37 Tauri was with a power of 320,seen actually touching the planet's
limb.—The star in neither instance suffered more diminution of
brightness than might fairly be attributed to the diffused light of
the planet.

From these observations, and the apparently contradictory ones
of Cassini and of Reener, the author of this paper infers, that the
existence of the extensive atmosphere of Mars is a subject highly
meriting further investigation.

He then directs attention to the fact that 37 Tauri was of a red
colour when in contact with Mars ; whilst 42 Leonis was under
similar circumstances of a blue colour: and, from inferences de-
pendent upon observation, states, that the apparent anomaly is
easily reconcilable, and that an hypothesis is not wanted to account,
on the occasion alluded to, either for the red colour of the one star,
or the blue colour of the other.

A paper was read, “ On the Inflexion of Light.” By John Bar-
ton, Esq. Communicated by Davies Gilbert, Esq. V.P.R.S.

The design of the author in undertaking the experiments of
which he gives an account in the present paper, is to carry on the
investigation of the phenomena of the inflexion of light from the
point at which it was left by Newton. He begins by examining
these phenomena in their simplest form, comparing the appear-
ance of the shadow of an opaque body on a screen of white paper
at different distances, with the appearance it would exhibit if the

rays

Royal Society. 301

rays passed by the edge of the body, without suffering any deviation
from a rectilinear course. It is well known that, under these cir-
cumstances, the real shadow is broader than the geometrical
shadow, indicating a deflexion of the rays from the edge of the
intercepting body. By varying the distances at which the obser-
vations are taken, it is found that the rays are not bent at a sharp
angle, but pursue a curvilinear course, the concavity of which is
towards the shadow, the curve itself resembling an hyperbola. A
luminous halo also appears beyond the shadow ; the breadth of
this halo agreeing accurately, at all distances, with the space which
the penumbra should occupy, if the rays were not bent. ‘The author
thinks it impossible to reconcile the explanation of these pheno-
mena given by Newton, with his own hypothesis concerning the
action of solid bodies on light, as stated in the ‘ Principia :” for, in
that hypothesis, the rays passing nearest to the edge of an intercept-
ing body are supposed to be bent towards the edge, as if attracted ;
whereas the explanation proceeds upon the supposition that they
are bent from that body, as if repelled. The actual hyperbolic
course of the rays is also inconsistent with that hypothesis, which
would assign to them a parabolic path. It also appears that the
breadth of the spectrum made by receiving the sun’s rays through
an aperture one tenth of an inch, or more, in width, is less than if _
the rays proceeded in straight lines; but if the aperture is very
much diminished, the result is reversed, the real spectrum being
broader than the geometrical spectrum.

The author conceives, that the whole of the observed phenomena
will admit of explanation, by assuming that light consists of mate-
rial particles, endowed with a power of mutual repulsion, in which
case they would obey the laws of elastic fluids ; and the course of the
rays might admit of comparison with the motions of the particles
of air, or other similarly constituted fluids, in flowing past an obstacle
opposed to their progress. He shows how this hypothesis furnishes
an explanation of the detlexion of the rays, and of the curvature of
their path ; and why that path resembles an hyperbola. He sup-
ports this theory by the analogy of the laws of heat, considered as
the properties of a material fluid, with those of light ; both exhibit-
ing the phenomena of reflexion, refraction, and polarization. The
author is inclined to believe that, besides the deflecting force, the
presence of which is already established, there exists also an in-
flecting force, which bends some of the rays towards the intercepting
body; and states a variety of considerations in support of this fact.
He explains, on the same principles, the phenomena described by
Newton under the appellation of fits of easy reflexion and easy trans-
mission, which Dr. Young has explained on the undulatory theory,
by the principle of interferences: but which may be considered as
analogous to the alternating movements of elastic fluids striking
against an opposing body, or entering by a narrow aperture; move-
ments which, in air, give rise to vibrations constituting musical
sounds,

The Society then adjourned over the Long Vacation, to meet
again on the 17th of November, ZOoLo-

302 Soological Society.

ZOOLOGICAL SOCIETY.
June 28, 1831. Rev. W. Kirby in the Chair.

Mr. Vigors exhibited, on the part of Captain Cook, specimens of
several Birds recently presented by that gentleman to the Society,
and also of some other Birds shot by him in the South of Europe,
some of which were interesting on account of their rarity, and others
with reference to the localities in which they were obtained. Among
them was a specimen of the Pica cyanea (Corvus cyaneus, Pall.), a
species not included by M. Temminck in the ‘Oiseaux d'Europe’,
which had been killed by Captain Cook in Spain. There were also
specimens of the Falco tinnunculoides ; of the Sturnus unicolor,
Marm., killed in Spain; of the Lanius meridionalis, Temm., a species
referable to the genus Collurio as recently distinguished by Mr.
Vigors ; of the Sylvia conspicillata, Marm., killed in Spain ; of the
Saxicole cachinnans and stapazina, Temm., also killed in Spain ; and
of the Fringilla domestica, Linn., which is met with in great num-
bers in Spain, and consequently extends far beyond the southern
limits assigned to the species by M. Temminck.

A collection of Birds presented to the Society by H. H. Lindsay,
Esq. of Canton, were laid upon the table. They were accompanied
by a letter from that gentleman to the Secretary, of the date of
Jan. 25, 1831, stating that the collection had been formed during
the summer of the previous year in the neighbourhood of Manilla,
and adding some notes respecting the various species, as well as the
names in the Tagallo or native language of the country. The col-
lection consisted of about fifty-six species, fifty of which at least had
not previously been in the Society’s Museum, or in any other public -
collection in England.—Mr. Vigors pointed out tie different species ;
and announced that a catalogue of them was in preparation, which
would shortly be submitted to the Committee. In the mean time
he characterized the following species.

Hrerax ERYTHROGENYS. Hier. capite et corpore supra, cauda

JSemoribusque intensé atris ; guld, collo in fronte, corporeque subtis
albis ; striga@ a rictu ad aures extendente rufa ; rostro albo, pe-
dibus nigris,

Statura Hier. cerulescentis.

Bureo noLospitus. But. superné brunneus, subtus brunnescenti-
rufus; capite, fasciisque duabus remigum rectricumque fusco-
atris ; nuchd et dorso, collo in fronte, pectore abdomineque toto,
tectricibusque alarum maculis albis ocellatis, harum maculis dimi-
nutioribus.

Statura tertid parte minor quam Buteo Bacha; ei speciei simil-
lima, differt tamen capite levi, corporeque toto maculato.
CAPRIMULGUS MACROTIS. Cap. intensé brunneus, rufo undulatus,
corpore subtus cauddque rufo fasciatis ; capite aurito scapulari-
busque rufo-brunneis, fusco undulatim punctulatis nigroque no-

tatis ; Lorque jugulari albo ad nucham extendente rufo.

Longitudo corporis, 15; rostri ad frontem 3, ad rictum, 14; ale
a carpo ad apicem remigis 2d, 103; caud@, 7; tarsi, .

Daceto Linpsayi. Dac. corpore supra brunneo, olivaceo et viridi

nilente,

Zoological Society. $03

nitente, guttis rufo-albidis notato, pectore abdomine crissoque albis,
illorum plumis, mediz abdominis exceptis, olivascenti-viridt mar-
natis ; capitis pileo saturate olivascenti-viridi, vittd superciliari
ties circumdato, deinde vitta per oculos nigra, alteraque sub-
oculari ferrugined marginato ; guld juguloque ferrugineis ; striga
utrinque maxillari lazulind ; remigibus fuscis ; rectrictbus omni-
bus ad apicem, duabus utringue externis ad latera, ferrugineo
notatis ; rostro subbrevt.

Longitudo corporis, 103; rostri, 13; al@ a carpo ad apicem re-
migis 3tia, 41; caude, 44, tarsi, 5. ‘ asf.

Daceto Lessonit. Dac, corpore supra brunneo, olivaceo et viridt
nitente, albido guttato ; capitis pileo saturaté olivaceo-viridi, vitta
superciliari ceruleo-viridi circumdato, deinde vitta alterd nigra
marginato ; collo in fronte corporeque subtus albo, pectoris abdo-
minisque plumis viridi-brunneo marginatis ; strigd utrinque maz-
illari viridi ; remigibus fuscis ; rectricibus omnibus ad apicem,
tribus utrinque externis ad latera, ferrugineo notatis ; rostro sub-
longo.

Longitudo corporis, 113; rostri 12; ale a carpo ad apicem re-
migis Stie, 45; caud@, 43; tarsz, 3.

Muscicara occipiTatis. Musc. corpore supra pallide lazulino,
capite colloque splendidioribus ; abdomine lazulino-albido ; ma-
culd occipitali grandi, torqueque gracili jugulari, sericeo-atris.

Longitudo corporis, 64.

RuIPIpuRA NIGRITORQUIs. Rhip. cinereo-grisea ; corpore subtis,
rectricumque, duabus mediis exceptis, apicibus albis ; fronte, tor-
queque jugulari nigris ; remigibus rectricibusque fuscis.

Longitudo corporis, 7.

IRENA CYANOGASTRA. Ir. nigrescenti-cyanea ; capite supra, fascia
tectricum alarum, uropygio, crissoque splendenti-cyaneis ; collo in
JSronte, genis remigibusque atris.

Statura Irene Puelle, et simillima ; differt abdomine caudaque
cyaneis, haud nigris, dorso cyaneo haud lazulino, et rostri culmine
plus elevato.

OrioLus AcRoRHyYNcHUS. Or. aureo-flavus ; vittd a rictu per
oculos extendente sinciputque obtegente latd, remigibus totis, rec-
tricumque basibus nigris ; rostro flavo, culmine elevato.

Longitudo corporis, 12; ale a carpo ad apicem remigis 4ta, 6 ;
cauda, 44 ; tarsi, 1; rostri, 12.

PsiTTaAcuLa RUBIFRONS, Psilt. viridis, subtus pallidior ; fronte,
dorso imo, rectricumque tectricibus coccineis ; remigibus cauddque
viridi-fuscis, rostro subelongato rufo.

Statura paulld major quam Psitt. Galguli.

Picus spitotornus. Pic. dorso alisque sanguineo-coccineis ; sub-
tits sordide albus, fuscescenti tiletos 3 capite colloque nigris,
guttis albis maculatis ; hujus maculis grandioribus ; remigibus
cauddque fuscis, harum pogoniis internis albo maculatis.

Longitudo corporis, 113.

Picus movestus. Pic, supra ater, alis ad latera apicesque subru_
Jescentibus ; capite in fronte genisque obscure coccineis, occtpit.

,
g ula

304 Ro0logical Society.

guld, jugulo, colloque grisescenti-atris, plumis macula minutissimd
albé ad apicem terminatis ; rectricibus duabus medvis elongatis.

Longitudo corporis, 15; ale a carpo ad apicem remigis 4tz, 6 ;
caud@, 6; tarst,1; rostri, 14.

LAMPROMORPHA AMETHYSTINA. Lamp. supra splendidé ame-
thystina ; abdomine albo, SJasciis viridi-amethystinis ornato ; rec-
tricibus lateralibus albo notatis.

_ Longitudo 73.

This description is taken from a bird in the state of change, the
amethystine feathers on the back, tail and breast, appearing par-
tially through a ferruginous ground, but sufficiently numerous and
defined to indicate the adult plumage. A younger bird in the col-
lection has nearly the whole of the upper body ferruginous with an
amethystine feather here and there breaking out. In a note ap-
pended to the description of the species, Mr. Lindsay states that the
natives considered them of extremely rare occurrence.

Nycricorax MAnivirnsts. Nyct. supra castaneo rufa ; collo in
Jronte, abdominis lateribus, femorum tectricibus, alarumque tec-
tricibus infertoribus pallidiori-rufis ; capite colloque supra nigris,
criste pennis longis pendentibus albis, apice nigro; pectore ab-
domine crissogue albis, ;

Statura paulo major quam Nyct. Caledonica, cui simillima; dif-
fert tamen colore cristz, colli in fronte, tectricumque inferiorum
alarum.

July 12, 1831. W. Yarrell, Esq. in the Chair.

Skins of numerous species of Mammalia obtained in Dukhun,
(Deccan), East Indies, were exhibited by Major W. H. Sykes, Corr.
Memb. Z.S. They were accompanied by a Catalogue of the Mam-
malia noticed by Major Sykes in Dukhun, which included also ob-
servations on the habits of each species, with occasional remarks on
their rarity or abundance, on their geographical range, and on
other interesting points connected with their history.

The following species were enumerated :—

Semnopithecus Entellus, F. Cuv. Makur of the Mahrattas.—Is
found in large troops in the woods of the Western Ghauts; and is
not venerated by the Mahratta people, nor do they object to its
being killed.

Macacus radiatus, Geoff. Waanur of the Mahrattas.—Inhabits
the woods of the Western Ghauts in small troops.

Pteropus medius, Temm, Wurbagool of the Mahrattas.—Is very
numerous in Western India, and such variations are found in the
colouring of different individuals in the same troop, that two or
three species might be supposed to be included in it, Some indi-
viduals have a greater length of body (144 inches) than is given to
the Pter. Javanicus by Dr. Horsfield.

Nyctinomus plicatus, Geoff. (Vespertilio plicatus, Hamilton ?)—
This Bat bears a very close resemblance to Dr. Horsfield’s Nyct.
tenuis.

RutnoLopuus Duxkuunensis, Sykes.—Rhin, supra murinus,

UMyra

Zoological Soczety. 305

infra albido-brunneus: auribus capite longioribus : antibrachio
corpus longitudine equante.

This Bat belongs to the same section as Dr. Horsfield’s Rhin.
ensignis, but differs from that species in being much smaller ; in
having the ears larger and more rounded ; the nose-leaf with the
upper lobe concave, ridged beneath and revolute above ; and the
front lobe oblong and notched inthe centre. It differs from the
Rhin. crumeniferus, Pér, and Le Sueur, (which is the Rhin. marsupi-
alis of M. Geoffroy’s lectures, andthe Rhin. Speorts of M. Desmarest,)
in being much smaller, this species having the fore arm nearly half
as long again as the Dukhun bat. The upper nose-leaf also is much
more produced, and finally the colour of the fur in this species is
reddish. The fore arm of the Rhin. Speoris as figured is 2 inches
2 lines long, and the body and head 2 inches 2 lines. In the Duk-
hun species the fore arm is only the length of the body. Expan-
sion of its wings 10 inches.

Sorex Indicus, Geoff. Cheechondur of the Mahrattas.—These
troublesome and disagreeable animals are very numerous in Dukhun,
but much more so in Bombay. The sebaceous glands in an old
male were observed to be very large, and the odour of musk from
them almost insupportable; while in an adult female the glands were
scarcely discoverable, and the scent of musk very faint. The
Sorex Indicus and Sor. giganteus are regarded by Major Sykes as
specifically identical, he having killed them in the same room, and
seen them frequently together.

Ursus labiatus, Blainv. Aswail of the Mahrattas.—In the skulls
of many individuals of this species which he has examined, Major
Sykes has never seen more than four incisor teeth in the upper and
six in the lower jaw; the two centre teeth standing a little in front
of the line of the rest. One individual, now in his possession, is so
young that he does not conceive that the deficient incisors can have
fallen out ; nor is there any appearance of dentition having existed
in the places which they should have occupied. He remarks that
it might be deemed advisable therefore to remove this animal from
the genus Ursus.

Lutra Nair, F. Cuv. Juhl Marjur or Water Cat of the Mah-
rattas.—The Otter of Dukhun differs only from the Nair in wanting
the white spots over the eyes, in having a white upper lip, and in
being somewhat larger.

Canis Dukuunensis, Sykes.—Kolsun of the Mahrattas.

Can. rufus, subtis pallidior: cauda comosd pendente : pupilla ro-

tundata.

This is the wild Dog of Dukhun. Its head is compressed and elon-
gated; its nose not very sharp. ‘he eyes are oblique: the pupils
round, irides light brown. ‘The expression of the countenance that
of a coarse ill-natured Persian Greyhound, without any resemblance
to the Jackal, the Fox, or the Wolf, and in consequence essentially
distinct from the Canis Quao or Sumatrensis of General Hardwicke.
Ears long, erect, somewhat rounded at the top, without any repli-
cation of the fragus. Limbs remarkably large and strong in relation

N.S. Vol. 10. No. 58. Oct. 1831. 2R to

306 Roological Society.

to the bulk of the animal; its size being intermediate between the
Wolf and Jackal. Neck long. Body elongated. Between the eyes
and nose, red brown: end of the tail blackish.

From the tip of the nose to the insertion of the tail 33 inches in
length: tail 84 inches. Height of the shoulders 163 inches.

None of the domesticated Dogs of Dukhun are common to Europe.

The first in strength and size is the Brinjaree Dog, somewhat
resembling the Persian Greyhound in possession of the Society, but
much more powerful.

The Pariah Dog is reterable to M. Cuvier’s second section. They
are very numerous, are not individual property, and breed in the
towns and villages unmolested.

Amongst the Pariahs is frequently found the Turnspit Dog, long
backed, with short crooked legs.

There is also a petted minute variety of the Pariah Dog, usually
of a white colour and with long silky hair, corresponding to a com-
mon Lap-Dog of Europe; this is taught to carry flambeaux and
lanterns.

The last variety noticed is the Dog with hair so short as to ap-
pear naked like the Canis gyptius. It is known to Europeans by
the name of the Polygar Dog.

Canis PALLIvES, Sykes.— Landgah of the Mahrattas.

Can. sordidé rufescenti-albidus ; dorso nigrescenti ferrugineoque
vario; pedibus totis pallidé ferrugineis: cauda sublonga pen-
dente.

This is the Wolf of Dukhun. Its head is elongated, and its muzzle
acuminated: a groove exists between the nostrils. Eyes oblique:
irides yellowish bright brown. Ears narrow, ovate, erect ; small
for the length of the head. Tail pendent, thin but bushy, extend-
ing below the os calcis. General colour of the fur a dirty reddish
white or whited brown. Along the back and tail very many of the
hairs are tipped black, mixed with others tipped ferruginous. The
tail ends in a black tip. The inner surface of the limbs, the throat,
breast and belly, dirty white. Legs pale. From the ears to the
eyes reddish grey, with a great number of short black hairs inter-
mixed; from the eyes to the nostrils, light ferruginous. The fur
from the occiput to the insertion of the tail is two or three inches
long, gradually shortening as it approaches the sides; hence all
over the body very short and lying close.

The description is taken from two three-parts grown animals.

Length from tip of nose to insertion of tail 35 to 37 inches; of
the tail 11 to 12 inches; the hair extending two inches beyond the
measurement.

These animals are numerous in the open stony plains of Dukhun;
but are not met with in the woods of the Ghauts.

Canis aureus, Linn. Kholah of the Mahrattas. — Jackals are
numerous in Dukhun. Major Sykes had in his possession at the
same time a very large wild male and a domesticated female.
The odour of the wild animal was almost unbearable. That of
the domesticated Jackal was scarcely perceptible.

CANIS

Zoological Society. 307

Canis Koxrer, Sykes.—Kokree of the Mahrattas.

Can. supra rufescenti-griseus, infra sordidé albus ; caude comose

apice nigro ; pedibus rufescentibus : pupilld elongatd.

The Fox of Dukhun appears to be new to science, although it
much resembles the descriptions of the Corsac. It is a very pretty
animal, but much smaller than the European Fox. Head short;
muzzle very sharp. Eyes oblique: zrides nut brown. Legs very
slender. Tail trailing on the ground; very bushy. Along the back
and on the forehead fawn colour with hair having a white ring near
to its tip. Back, neck, between the eyes, along the sides and half
way down the tail reddish grey, each hair being banded black and
reddish white. All the legs reddish outside, reddish white inside.
Chin and throat dirty white. Along the belly reddish white.
Ears externally dark brown, and with the fur so short as to be
scarcely discoverable. Edges of eyelids black. Muzzie red brown.

Length <2 and 22: inches: of the tail 114 to 12 inches.

Viverra Indica, Geoft., (Viv. Rasse, Horsf.) Juwadee Manjur,
or Civet Cat of the Mahrattas.—There are two varieties of this
species of Viverra in Dukhun; one inhabiting the woods along the
Ghauts; the other the country eastward of the Ghauts. The
former has the ground colour much grayer, and the lines more dis-
tinctly broken into spots. The other variety has a ferruginous tint,
and the four black longitudinal lines or stripes on the sides of the
neck are more marked: it attains the length of 284 inches.

Herpestes griseus, Desm. Moongus of the Mahrattas.—Some
specimens of this animal measure from 193 to 204 inches from the
tip of the nose to the insertion of the tail, and the tail 15 to 165
inches.

Paradozurus Typus, F. Cuv. Ood of the Mahrattas——This
animal is by no means rare in Dukhun. Its carnivorous propensi-
ties are very strong, but it may be fed entirely on rice and clarified
butter. Inthe stomachs of some individuals examined at Poona,
were found fruit, vegetables, and Blatia.

Hyena vulgaris, Cuy. Turrus of the Mahrattas.—Hyenas are
numerous in Dukhun, and are susceptible of the same domestica-
tion as a dog.

Felis Tigris, L. Puttite Wagh or striped Tiger of the Mahrat-
tas.—Royal tigers are so numerous in the province of Khandesh
that 1032 were killed from the years 1825 to 1829 inclusive, accord-
ing to the official returns. They are much less numerous in the
collectorates of Poonah, Ahmednuggar, and Dharwar.

Fel. Leopardus. Cheeta of the Mahrattas.—This is regarded by
Major Sykes as the Leopard of M. Temminck’s monograph of the
genus Felis. It is a taller, longer, and slighter built animal than
the succeeding, which he considers as the Panther. It differs also
in more of the ground colour being seen, in the rose spots being
much less curved, and in other particulars. The natives of Dukhun
consider the Cheeta and succeeding Cat as distinct animals. The
Cheeta is extremely rare. On the couatrary, the

Fel. Pardus, Beebeea Baugh of the Mahrattas, is so abundant that

2R2 472

308 Soological Society.

*

472 were killed from 1825 to 1829 inclusive, in the four collec-
torates of Dukhun. It exactly resembles the animal figured as the
Panther of the ancients in Mr, Griffiths’s Translation of the ‘ Régne
Animal.’ It differs from the preceding in its smaller size, stouter
make, darker ground colour, and in its crowded rose rings.

Fel. jubata, L., and Fel. venatica, H. Smith. Cheeta of the
Mahrattas.—These animals appear to be identical, the specific diffe-
rences deduced from the hair originating in domestication. A skin
of the wild animal has a rough coat, in which the mane is marked,
while domesticated animals from the same part of the country are
destitute of mane and have a smooth coat.

Fel. Chaus, Guid. Mota Rahn Manjur or larger wild Cat of the
Mahrattas.

Fel. torquatus, F. Cuv. Lhan Rahn Manjur or lesser wild Cat of
the Mahrattas.—The specimens from Dukhun differ only from the
Fel. torquatus figured in the third volume of the ‘ Histoire Naturelle
des Mammiféres in the ears externally being tipped dark brown,
and in having two narrow stripes behind the eyes instead of one.
The sexes resemble each other in colour, marks and size.

Mus giganteus, Hardw. Ghoos of the Mahrattas. —In fully
grown individuals of the well-known Bandikoot Rat, none of the
teeth are tuberculous. Its body attains a length of 16,7, inches ;
the tail 11,45, inches.

Mus decumanus, Pall. Chooa of the Mahrattas—The Norway
or brown Rat abounds in Dukhun.

Mus Musculus, L.—The Mouse is comparatively rare in Dukhun.

Another Mouse was observed by Major Sykes, which he believes
to be new. It is bright light chestnut above, reddish white below.
Tail much longer than the body: size of the common mouse.
Found only in fields and gardens.

Scrurus Eveuinstonit, Sykes.—Shekroo of the Mahrattas.

Sc. supra nitidé castaneus, infra rufescenti-albidus ; caud@e dimidio

apical pallidé rufescente.

This very beautiful animal is found only in the lofty and dense
woods of the Western Ghauts. It is of the size of the Sc. maxi-
mus, and the general arrangement of its colours is the same ; but
its colours are invariable, and do not present those differences
which exist in the Sc. maximus.

Ears and whole upper surface of the body, half way down the
tail, outside of the hind legs and half way down the fore legs out-
side, of a uniform, rich reddish chestnut. The whole under surface
of the body, from the chin to the vent, inside of limbs and lower
part of fore legs, crown of the head, cheeks and lower half of tail, of
a fine reddish white, the two colours being separated by a defined
line and not merging into each other. Feet of a light red. Fore-
head and down to the nose reddish brown, with white hairs inter-
mixed. Jrides nut brown. Ears tufted. Length from the tip of the
nose to the insertion of the tail 20 inches ; of the tail 154 inches.

Dedicated to a very distinguished person and a zealous promoter
of scientific research, the Hon, Mountstuart Elphinstone.

Se.

Zoological Society. 309

Sc. Palmarum, Briss. Khurree of the Mahrattas.—The Palm
Squirrel is very abundant in gardens in Dukhun.

Hystrix teucurus, Sykes.— Sayal of the Mahrattas.

Hyst. cauda alba.

This animal appears to be distinct from the European species,
which it closely resembles in form and covering. It is nearly a third
larger. All the spines and open tubes of the tail are entirely white,
which is not the case in the Hyst. cristata. The spines of the
crest also are so long as to reach to the insertion of the tail. The
ears are much less rounded, and the nails are shorter, infinitely
deeper and more compressed, and with deep channels below.
The white gular band is more marked; and, finally, the Asiatic
species is totally destitute of hair, spines where wanting being
replaced by strong bristles even down to the nails.

Lepus nigricollis, F. Cuv. Sussuh of the Mahrattas.—This species
of Hare is very common in the stony and bushy hills of Dukhun.

Manis pentadactylus, L. Kuwlee Manjur or tiled Cat of the
Mahrattas.—Very common in Dukhun, living on white ants.

Sus Scrofa, L. Dookur of the Mahrattas— Wild Hogs are nume-
rous in Dukhun, and the males attain to a very great size. Every
village also abounds with Hogs, but any property in them is equally
abjured by individuals and the community. These village Hogs are
of the same colour as the wild animal, mostly a rusty black, and the
only variations are slate black or slate intense brown ; but it is not
above two thirds of the size of the latter. Tail never curled or
spirally twisted.

Equus Caballus, L. Ghora of the Mahrattas—A fine breed
of Horses exists on the banks of the Beema and Mahn rivers in
Dukhun, supposed to have been improved by the Arabian blood.
The variety called Pony by us, and Tuttoo by the Mahrattas, is
sedulously propagated.

Equus Asinus, L. Gudha of the Mahrattas.— The Ass of Dukhun
is very little larger than a good mastiff or Newfoundland dog. It
is said to be found wild in Katteewar.

Camelus Dromedarius, L. Oont of the Mahrattas—The Dro-
medary is rarely bred in Dukhun, but is in very general use. The
two-humped Camel is not known.

Moschus Meminna, Erx\. Peesoreh of the Mahrattas.—This beau-
tiful little animal is found in considerable numbers in the dense
woods of the Western Ghauts, but never on the plains.

Cervus equinus, Cuv, Sambur of the Mahrattas.—Abounds in
the Ghauts of Dukhun and in Khandesbh, and is no doubt the same
as the Malayan Rusa figured in Mr. Griffiths’s Translation of the
‘ Régne Animal’. It wants the size of the Cerv. Aristotelis of Bengal,
also called Sambur (not Samboo), and is not so dark in colour.

Cerv. Muntjak, Zimm. Baiker of the Mahrattas.—This beautiful
species of Deer is a native of the Western Ghauts of Dukhun, and
is never seen on the plains. It has large suborbital sinuses, which it
uses in the manner of the Ant. Cervicapra.

Antilope Cervicapra, Pall. Bahmunnee Hurn of the Mahrattas.—
This animal abounds on the plains of Dukhun, in flocks of scores,

but

310 xoological Society.

but is not met with in the Ghauts. The suborbital sinuses are ca-
pable of great dilatation, and the animal applies them to objects as
if for the purpose of smelling.

Ant. Bennerrtil, Sykes. Ant. cornubus nigris, lyratis, apicibus
levibus leviter introrsum antrorsumque versis, ad basin ultra me-
dium annulatis (annulis 8-9) ; rufescenti-brunneus, infra albus,
Jascia laterali haud conspicud ; fascia media strigaque ab angulo
oculi ad oris angulum extensa nigris ; cauda nigra.

Kalseepee or Black Tail of the Mahrattas. Goat Antelope of Eu-

ropeans,

This Antelope is found on the rocky hills of Dukhun, rarely
exceeding three or four in a group, and very frequently soli-
tary. It helongs to the same section as the Ant. Dorcas. Horns
erect, slightly diverging from each other, bending slightly back-
wards at first, subsequently with their points bending forward:
ringed for 2 of their length. The whole upper surface and out-
side of the limbs rufous or red brown. Under surface and inside of
the limbs white. Tail black. A black patch on the nose. A black
narrow streak from the anterior corner of each eye towards the angle
of the mouth, Suborbital sinuses very small; in dried skins not
observable; nor does the animal dilate them unless very much
alarmed. Limbs long and slender ; black tufts at the knees. Body
light. The female has horns, but they are slender, cylindrical, and
without rings. The buttocks present a heart-shaped patch of white.
Unlike the Ant, Cervicapra it carries its tail erect when in rapid mo-
tion. It stands as high as the Bahmunnee Hurn, but has less bulk.

There is another Ante/ope found in Dukhun, which Major Sykes
has not yet identified, on account of the immature age of his
specimen. It is brown above, whited brown below. Horns cylin-
drical, pointed, without rings, Its general appearance is that of
the Ant. rufescens and Ant. silvicultria.

Capra Hircus, Linn. Bukee of the Mahrattas.—The goats in
Dukhun are gaunt, stand high on their legs, have the sides much
compressed, and are covered with long shaggy hair, which in most
is black, Ears nearly pendent. Jrides ochrey yellow or reddish
yellow. Tail always carried erect in movement.

Ovis Aries, Linn.—The variety of Sheep most extensively bred
in Dukhun, has short legs, short thickish body, and arched
chaffron. The wool is short, crisp and coarse, and is almost univer-
sally black. In most individuals there is a white streak or line from
the anterior angle of each eye towards the mouth, and a white
patch on the crown of the head.

Ant, picta, Pall. Damalis risea, H. Smith. Rooee of the Mah-
rattas. Nylghaz of the Persians,—This animal is an inhabitant of
the Western Ghauts of Dukhun.

Bos Taurus, var. Indicus. (Bos Indicus, Linn.) Pohl and Byl of
the Mahrattas——This animal, remarkable for its hump, is when
early trained to labour or to carriage nearly destitute of it. Dwarf
cattle are not met with in Dukhun.

Bos Bubalus, Br, Male called Tondgah ; Female, Muhees of the

Mahrattas.

Zoological Society. 311

Mahrattas—The Buffaloe of Dukhun is the long-horned variety,
and is mostly bred in the Mawals or hilly tracts along the Ghauts.

Major Sykes subsequently called the attention of the Committee
to a Monkey presented by him to the Society, and now living at
the Gardens. It was obtained at Bombay, where it was believed
to have been taken from Madagascar; and as it has some characters
in common with the Cercopitheci (especially with the group of which
the Cerc. Sabeus forms a part) and the Semmnopitheci of India, it
was remarked that it may ultimately prove to be a connecting link
between the African and Asiatic monkeys. It wants the long limbs
of the Semnopitheci ; and although its tail is very long, it is not par-
ticularly thin. Major Sykes referred it provisionally to the Semno-
pitheci, until by an examination of its posterior molars its real station
in the system should be determined.

It is thus characterized :

SemMn.? ALBoGULARIS, Sykes. Semn.? supra flavo nigroque,
infra albo nigroque irroratus ; guld alba; artubus nigris : mysta-
cibus latis aures pené obvelantibus ; superciliorum pilis rigidis
exstantibus.

Hab. in Madagascar ?

Its canines are remarkably long (nearly 3 of an inch), slender,
sharp; the incisors very short and even. Head rounded and short.
Ears very small, nearly rounded, and for the most part concealed in
the long hair about the head. Eyes deeply seated, and shaded by a
continuous arch of long hairs directed forwards. rides broad; of
a brown ochre colour. Hair forming a bunch on each cheek and
resembling whiskers: no beard. Cheek pouches rudimentary only,
not observable externally, even when filled, being concealed by the
bushy hair of the cheeks. Thumbs of anterior hands short and di-
stant ; those of the posterior long. Whole of the upper surface of
the animal of a mingled black and yellowish ochre colour, each
hair being banded black and ochre; the black prevailing on the
shoulders, the ochre on the back and flanks. Under surface griz-
zled white and black. Anterior limbs uniform black ; posterior black
with a little of the dorsal colour. Chin and throat pure white.
Tail black, half as long again as the body.

The manners of this monkey are grave and sedate. Its disposi-
tion is gentle but not affectionate: free from that capricious petu-
lance and mischievous irascibility characteristic of so many of the
African species, but yet resenting irritating treatment, and evincing
its resentment by very smart blows with its anterior hands. It never
bit any person on board ship, but so seriously lacerated three
monkeys, its fellow passengers, that two of them died from the
wounds. It readily ate meat, and would choose to pick a bone,
even when plentifully supplied with vegetables and dried fruits,

Mr. Gray exhibited a specimen of a Tortoise which he regarded
as the type of a new genus in the family Emydide, 1t is charac-
terized as follows ;

PLATYSTERNON,

Sternum latum, antice truncatum, posticé emarginatum. Scutella
sterni

312 Soological Society.

sterni 12: quorum duo anteriora brevia, luta, per totam sterni
latitudinem extensa. Symphysis scutellorum pectoralium abdo-
minaliumque extremitatibus tecta: scutellis axillari inguinalique
magnis ; inter que scutellum tertium accessorium ts simile ; scu-
tella hec tria in suturam symphysis inserta.

Caput maximum, cute corned continud tectum. Cauda longissima,
teres, attenuata ; superné serie unica, inferné duplici, sgquamarum
tecta ; haud cristata.

This genus is intermediate between Emys and Chelydra. It has
the broad sternum and simple tail of the former genus; and pos-
sesses, in common with the latter, a large head, and the peculiar
plates which are situated between the outer extremities of the pec-
toral and abdominal, and the marginal dorsal plates. It differs from
Chelydra, however, in the peculiar plate which covers the symphysts
of the sternum being here comparatively very small, not exceeding
in size the axillary and inguinal plates, and in its being inserted in
the same line with them.

The only species known was characterized as the

PLATYSTERNON MEGACEPHALUM,. Plat. capite brunneo, obscure
nigro radiato : testd superne saturate brunned, infra pallide flava :
marginibus scutellorum sulcis aliquot obscuris striisque radian-
tibus confertis.

Long. teste, 34 unc.; sterni, 23: latitudo teste, 25; sterni an-
ticé, 23: long. capitis 25; caudex, 3.

Hab. in China.

In illustration of the conterminous genus Emys, Mr. Gray exhi-
bited a specimen of the Em. Caspica, Schw., recently obtained from
the Mediterranean.

Mr. Gray also exhibited a specimen of the animal (Ocythoé) found
in the shells of the genus Argonauta, in illustration of some obser-
vations on the disputed question of its parasitic or non-parasitic
nature. He stated that he had lately examined ten specimens, four
of them referable to Ocythoé Cranchiz, and the remainder to Ocy-
thoé antiquorum ; there being, however, little to distinguish them
except the size. All these specimens, as well as all those which
have been figured, were females, and had eggs inclosed in the hin-
der part of the shell, in the cavity which is uniformly found behind
the body of the animal. In all, the posterior s7phon was placed more
or less exactly in the keel of the shell, but the body did not always
occupy a symmetrical position with regard to it, the eye of one side.
being sometimes nearer to the spire than that of the opposite side,
Only one or two of these individuals had their bodies marked with
the ridges of the shells, the impressions of which were, however,
mostly observable upon the arms. The animals all appeared to be
retained in the shells by the inflection of the anterior pair of arms.
Mr. Gray added that he had also lately seen several specimens pre-
served without shells, and having their bodies shaped exactly like
that of the common Octopus, without the slightest appearance of
their having been inclosed in shells: the history of these specimens

he

Intelligence and Miscellaneous Articles. 313

he was unable to trace, and he could not therefore atlirm that they
were found in the state in which he observed them.

From these facts Mr. Gray stated that he was inclined to regard
it as probable that the Ocythoé is only parasitic in the shell of Ar-
g2nauta ; that the shells are only resorted to by females during the
breeding season for the protection of their eggs ; and that the chief
purpose of the dilated portion of the anterior arms is to retain the
animal in the shell. He remarked, that no author, so far as he was
aware, had distinctly stated of his own observation that these parts
are expanded in the form of sails before the wind, a service which
they seem to be incapable of performing, except in poetic fiction.

XL. Intelligence and Miscellaneous Articles.

RED COLOURING MATTER PRODUCED BY THE ACTION OF
NITRIC ACID UPON ALCOHOL, &c. BY M. ROUCHAS.

b iy yar equal quantities of nitric acid and alcohol act upon each

other, the products are, azote, nitrous and nitric oxide, car-
bonic, acetic and nitrous acid, water, and nitric ether : if one part of
alcohol and three parts of acid be used, oxalic acid is obtained.
M. Rouchas remarks, that having lately caused three parts of nitric
acid to act upon one part of alcohol, the above-mentioned products
not only resulted, but also that when ammonia, potash, or soda, or
their carbonates or bicarbonates, were added to the solution, a fine
red colour was produced, which he considers as a new fact. The
same effects are produced by sugar, starch, and some other vege-
table substances.

M. Rouchas observes that this colour does not appear to be
similar to that which accompanies purpuric acid; and he concludes
from his experiments :

Ist, That nitric acid, while acting on alcohol, sugar, starch, &c.
among other well-known products, occasions the formation of a
peculiar non-azotized red colour,

2ndly, That the alkali acts in developing the colour merely by
neutralizing the excess of nitric acid which exists in the solution,
and thus separating it; for afresh quantity of nitric acid has the
property of causing the red colour to disappear, and it may be re-
produced by a fresh addition of an alkaline substance,

Srdly, That this red principle is chemically composed of the
same elements as sugar, alcohol, starch, &c., the hydrogen being
in smaller quantity.

4thly, That the red colour developed on mixing sugar or gums
in solution with nitrate of silver, arsenic acid with sugar, chlorine
or bromine with sugar, is identical with the red principle obtained
when nitric acid acts upon sugar, alcohol, &c,

Sthly, That nitrate of silver, nitric acid, arsenic acid, chlorine
and bromine, act upon the vegetable substances submitted to their
agency, the first three by dehydrogenating them by means of their

N.S. Vol. 10. No. 58. Oct. 1831. 28 oxygen

314 Intelligence and Miscellaneous Articles.

oxygen, and the last two by combining with their hydrogen, on
account of the great affinity for it to form hydracids.—Journal de
Pharmacie, March 1831.

PERCHLORIC ACID.

M. Sérullas has discovered that perchloric acid is obtained by
distilling chloric acid. The watery part is to be rejected as use-
less, and a colourless dense liquid is observed to adhere to the sides
of the vessel. When the heat is increased, and which ought to be
sufficiently strong to heat every part of the body of the retort, the
liquid passes into the receiver; this is perchloric acid: although
concentrated, it does not inflame paper like chloric acid, but it
gives to the paper, when put in contact with a red-hot coal, the
property of forming very vivid sparks.

During the distillation of the chloric acid, chlorine and oxygen
separate, and a portion of the latter combining with the undecom-
posed chloric acid, it passes to the state of perchloric acid, which
is very permanent, and may be distilled at a high temperature with-
out any decomposition. The acid distilled has a light rose colour,
probably derived from a little manyanesiate of potash contained in
the chlorate of potash; but on concentrating it by heat, it becomes
colourless. To be quite sure that the chloric acid is pure, it may
be redistilled. This process is much preferable to that of Count
Stadion, which is complicated, and also dangerous in the execution.
There remained some doubts as to the composition of perchloric
acid. M. Sérullas has ascertained that it is composed of two atoms
of chlorine and seven atoms of oxygen.—Jbid. p. 142.

RED SOLUTIONS OF MANGANESE.

The red colour of the sulphate of manganese procured under
certain circumstances, has been attributed to the presence of per-
oxide, deutoxide and red oxide. Mr. Pearsall is, however, of opi-
nion that it is caused by manganesic acid. Among other reasons
which he assigns for this opinion, are the following : the red solu-
tions of manganese and the solution of manganesic acid are both
alike in colour and in bleaching power ; both become colourless by
the same agents, and lose their bleaching power by losing their
coloured state; they are similarly affected by reagents, and afford
similar red crystallized salts: when deprived of colour they afford
a crystallized colourless proto-salt, and both are compatible with
certain other solutions of other substances.— Journal of the Royal
Institution, Aug. p. 62.

POWERFUL ELECTRO-MAGNET.

Professor Henry and Dr. TenEyck have constructed an electro-
magnet for Yale College, which is stated to have sustained 2063
pounds. The magnet is wound with 26 strands of copper bell-wire,
covered with cotton thread, 31 feet long; about 18 inches of the
ends are left projecting, so that only 28 feet of each actually sur-
round the iron; the aggregate length of the coils is therefore

728 feet.

Intelligence and Miscellaneous Articles. 315

728 feet. Each strand is wound on a little less than an inch ; in
the middle of the horse-shoe it forms three thicknesses of wire, and
on the ends or near the poles it is wound so as to form six thick-
nesses. With a battery of 43 square feet, the magnet suspended
2063 pounds. The effects of a larger battery were not tried. It
induced magnetism in a piece of soft iron so energetically as to
raise 155 pounds. When two batteries were employed so that the
poles could be rapidly reversed, a curious fact was observed. After
one of the batteries had been removed, the curvature, with a weight
added, in all 89 pounds, remained suspended and did not fall when
the poles were reversed. This effect must have been instantaneous,
otherwise the weight must have fallen ; as there was an instant when
the magnet could have had no power. It was attempted to decom-
pose water by this magnet, but without success.—Jbid. Silliman’s
Journal,

MARKING-INK FOR LINEN.
M. Henry, senior, recommends the following as a marking-ink
for linen tu be employed in hospitals.
Sepeeror ramming 002) 3 PONS Mi iiet, FNC ba, ths 1 pound.
Acetic acid (Vinaigre de Bois) sp. gr. about 1-052.. 2 pounds.
Mix the iron filings with half the vinegar ; shake the mixture
frequently, and as it becomes thick, add the rest of the acetic acid,
pe Sb Digs ee RD Mtl as Ld abe he Ea aE 1 pound.
Heat the mixture to favour the action of the acid upon the iron;
and when it is dissolved, add

Senprate ofiron: | 672 6 ot dd as alec ss s(x, or POUHOR,
1 gl pk a ERD ca ca ld ae Ua ahaa 1 pound.
Previously dissolved in water.........._... ae eres: 4 pounds.

Mix them thoroughly while hot; these quantities usually give
12 pounds of product. ‘In order to employ it, the linen is stretched
upon a table, and copper characters [stencils?] and a hair-brush
are used.— Journal de Pharmacie, J uly 1831.

MONTHLY AMERICAN JOURNAL OF GEOLOGY AND NATURAL
SCIENCE.

We have lately received the first Number (for July) of this work,
which is published at Philadelphia, and conducted by G. W. Fea-
therstonhaugh, Esq., F.G.S., &c. &c. Of the design, as expressed in
the Prospectus, which contains some candid remarks on the state of
the cultivation of natural history in the United States, and on the
means necessary for its improvement, we highly approve. Of the
execution also, so far as the Number before us will enuble us to form
a judgement, we are happy to express our approbation. Desirous of
seeing our Transatlantic brethren the emulous yet generous rivals of
the cultivators of science in Britain, in every department of human
knowledge, Mr. Featherstonhaugh’s Journal has our most cordial
wishes for its success,

The Number begins with the “ Prospectus,” which is followed by
an “ Introduction,” giving some excellent remarks on the Mosaic
history of the Creation, as fully reconcileable with the inferences of

282 geology,

316 Intelligence and Miscellaneous Articles.

geology, but leaving geologists to the free exercise of induction from
observed facts, in ascertaining the circumstances and phenomena
under which that work of Omnipotence was effected. This is suc-
ceeded by a notice by the Editor (illustrated by a good lithograph)
of Rhinoceroides Alleghaniensis, a new fossil genus of Pachydermata,
a portion of a jaw of which has been discovered in the diluvium or
alluvium of Pennsylvania, agreeing in most of its proportionate di-.
mensions with that of Rhinoceros, but differing from it by “ the great
space between the intermaxillary suture (very distinct in the fossil,)
and the place of the first molar, being in the fossil twice as much as
in the recent R. Indicus;”’ and also by “ the occupation of two inci-
sors in the fossil, of the space allotted to one incisor in the R. Indi-
cus.”

The next article, which is also by the Editor, is ‘‘ On the An-
cient Drainage of North America, and the Origin of the Cataract of
Niagara,” illustrated by a lithographic “ flat view” of that cataract.
In a note to this paper, we have the following remark on a subject
not long since discussed in our pages: ‘ That the recession of these
falls is effected as Mr. Lyell supposes, we have never doubted ; but
a long and familiar acquaintance with the cataract has induced us to
adopt the opinion we have just seen announced by the Rev. W. D.
Conybeare (Phil. Mag. and Annals, No. 52, April 1831, page 267),
that in forming the first estimates of this [Mr. Lyell’s] computation
[that Lake Erie will be reached in 30,000 years] ‘some partial degra-
dation of the strata has been here mistaken for the general retrogra-
dation.’”” We then have “ The Diary of a Naturalist,” kept at the
Bartram Botanic Garden, near Philadelphia. Some observations on
the vagaries of nomenclature recently exhibited by certain French
geologists, compose the next article. The remainder of the Number
consists of some excellent remarks on the adjudication of the first
Wollaston prize to Mr. Smith, animadverting with much justice on
Dr. Brewster's treatment of the Geological Society on that account ;
an account of Lord Bridgewater's bequest, from the Phil. Mag. and
Annals for March last; an essay by a correspondent on the “ Influence
of Climate on the Fruitfulness of Plants,’ and various scientific me-
moranda, including a notice of some newly discovered remains of the
Mastodon, among which is a skull in better preservation than any yet
discovered of this animal.

Again we express our cordial wishes for the prosperity of this work,
which we are convinced will perform very important services to
science.

September 28, 1831.

MR. HARVEY’S RESEARCHES ON NAVAL ARCHITECTURE.

Mr. Harvey of Plymouth has received from the Emperor of Russia,
a splendid diamond ring, on account of his recent researches on
ship-building. A very flattering letter accompanied the present.

ALTERA-~

New Patents. $17

ALTERATIONS AND ERRATA
In Mr. Waterston’s “‘ Exposition of a New Dynamico-Chemical Prin-
ciple,” inserted in the Phil. Mag. and Annals for September *.
1:5708 cp
5236 df
beginning with “‘if no elastic force is supposed to be exerted. Since
perfect resiliency however” &c., and ending with “ further to diminish
the rectilineal motion of the particles.”

Insert in place of the above.—If we suppose it equally probable that
the point of concurrence p, may be anywhere situated in the lines
ab, df, the extreme cases will be where it coincides with their extre-
mities and centres of gravity. In the former by the above formula
the rotatory momentum would be 3 of the whole, in the latter it is 0.
The mean quantity or +3, will therefore be the ratio of the whole
quantity of rotatory momentum generated in the medium on this
supposition. But amidst the diversified concourse of the particles,
there are peculiar modes of concurrence which do not hold with this
supposition and which in regard to the total effect throughout the
medium will tend to augment the above ratio.

In page 175 leave out the words following the formula

Page 170, line 23, for actual read active.

— 174, — 31, — particulars — postulates.

— 177, — 28, — will continually replace the, read will be
continually renewed by the

— 179, — 34, — theories read theorems.

LIST OF NEW PATENTS.

To W. Sumner, Hose, Leicestershire, lace-maker, for certain
improvements in machinery for making lace, commonly called
bobbin net.—Dated the 3rd of February, 1831.—6 months allowed
to enrol specification.

To G.G. Gardner, New York, but now residing at Thread-
needle-street, gentleman, for an improved roving machine. Com-
municated by a foreigner.—11th of February.—6 months.

To W. W. Richards, Birmingham, gun-maker, for certain im-
provements in the touch-holes and primers, suitable to percussion
guns, pistols, and all sorts of fire-arms fired upon that principle.—
11th of February.—2 months.

To J. Gunby, George-street Sand Pits, Birmingham, artist, for
an improved method or methods of combining glass with metal,
metals, or other substances, applicable to various useful and orna-
mental purposes.—11th of February.—2 months.

To C. Guillotte, Crispin-street, Spitalfields, machine-maker, for
an improvement in the rack applicable to the battons of looms, or
machinery for weaving plain or figured ribbons. Partly communi-
cated by a foreigner.—11th of February.—6 months,

* Communicated by Mr. Waterston.—We received this article last
month, but too late to allow of its insertion in its proper place.

LUNAR

318 Meteorological Observations for August 1831.

LUNAR OCCULTATIONS FOR OCTOBER.

Occultations of Planets and fixed Stars by the Moon, in October
1831. Computed for Greenwich, by THomas HENDERSON, Esq. ;
and circuluted by the Astronomical Society.

Immersions. Emersions.

Stars’
Names. Sidereal| Mean

time. |solartime,| 3
i}

Magnitude.
Ast. Soc. Cat.
No

h m| h m
w-57 5 | 255/22 33] 8 35 44):
eer 17 39

8 26| 18 26 | 303
1 39] 11 36 | 334
0 59| 6 54 |274
0 24) 10 18 | 321
ty)
ty)
1

12} 10. 5 | 352

24| 10 17 | 229

OV i 1 15 eo
412} 14 5 |308
23-19} 9 9 | 308
) touching Star.
Occulted to places furthe
South,
2 6| IL 55 | 245 | 207
7 10 | 16 51 | 250 | 243
5 40) 15 6 | 288) 249

75 Tauri...) 6

(99) Tauri} 5°6 | 516) 0 20] 10 13 | 93| 54
Aldebaran} 1 | 528) 3 5] 1259] 84] 63
24/115 Tauri | 5-6| 651) 22 33] 8 23 76] 38
119 Tauri | 5:6

120 Tauri | 6 | 667} 115} 11 5 |139] 99
26| ¢ Geminor.| 6 | 951) 5 57| 15 38 |100} 74
30| ¢ Leonis...} 4 es 4 52} 14 18 | 38) 35

METEOROLOGICAL OBSERVATIONS FOR AUGUST 1831.

Gosport :— Numerical Results for the Month.

Barom. Max. 30-296, Aug. 22. Wind N.E.—Min. 29-655, Aug.7. WindS.E.
Range of the mercury 0-641.

Mean barometrical pressure for the month .........ssssecseessesesers 29-986
Spaces described by the rising and falling of the mercury............ 3:599
Greatest variation in 24 hours 0-317.—Number of changes 16.

Therm. Max. 77°. Aug. 1. Wind N.E.—Min. 52°. Aug.17. Wind N.
Range 25°.—Mean temp. of exter. air 65°'13. For 31 days with © in (065-43
Max. var. in 24 hours 22°-00.— Mean temp. of spring-water at 8 A.M. 52-98

De Luc’s Whalebone Hygrometer.
Greatest humidity of the atmosphere, in the evening of the 9th....... 92°
Greatest dryness of the atmosphere, in the afternoon of the Ist...... 44-0
Rangelofithemndexis:sgetscessttccsus¥suethds aeseu 3. -cd= aide. s.0ccceuceecuaeens 48-0
Mean at 2 P.M. 55°-5.—Mean at 8 A.M. 64°4.— Mean at 8 P.M. 70:2
of three observations each day at 8, 2, and 8 o’clock......... 63°3
Evaporation for the month 3-35 inches.
Rain in the pluviameter near the ground 1-815 inch.
Prevailing wind, West.
Summary of the Weather.
A clear sky, 2; fine, with various modifications of clouds, 21; an over-
cast sky without rain, 5; rain, 3.—Total 31 days.

Clouds.

Meteorological Observations for August 1831. 319

Clouds.
Cirrus, Cirrocumulus. Cirrostratus. Stratus. Cumulus. Cumulostr. Nimbus.
24 19 30 0 26 20 14

Scale of the prevailing Winds,
me ONE. BE Oe. WS INL. Days.
3h 2 Sepia | Ne Oe 73 6 31

General Observations. — This month has been remarkably fine, dry, and
warm, so that very little interruption was experienced in getting in the full
crops of corn, which were carried in good condition in this neighbourhood.
The only heavy and continued rain was on the 2nd instant, when upwards
of an inch fell in seven hours, accompanied with lightning and thunder,
and crossing winds; but on this occasion there was scarcely any difference
in the pressure of the atmosphere. In the evenings of the 10th and 11th
twelve meteors appeared ; many of them were large, with long sparkling
trains. On the 17th lightning and thunder again occurred, and, as neaily
opposite winds prevailed at the same time, a smart shower of rain fell here;
for cpposite winds, which of course have different temperatures, invariably
condense the atmosphere they pervade, and induce rain. Some injury was
done by the lightning in Hampshire. On the 18th, 19th, 20th and 21st,
strong gales of wind blew, first from the West, then from the North.

The mean temperature of this month is about one and a half degree
higher than the mean of August for many years past, which was occasioned
by the comparative dryness of the weather, and the consequent strong ter-
restrial radiation.

The atmospheric and meteoric phenomena that have come within our
observations this month, are, two solar halos ; seventeen meteors; lightning
and thunder on two days ; and four gales of wind, two from the North, and
two from the West.

REMARKS,

London.— August 1. Fine: rain at night. 2. Heavy showers, with thunder.
3. Rain. 4. Cloudy: lightning at night. 5. Warm, with heavy thunder-
showers. 6—8. Veryfine. 9.Fine: rain. 10—15. Fine. 16. Slight
fog: sultry: lightning at night. 17. Fine in the morning, with showers at
intervals: a very heavy thunder-storm in the afternoon, with rain in tor-
rents, mixed with hail; the latter however was so nearly melted that it did
but little damage. 18.Fine. 19, 20.Windy: rain at nights. 21.Showers:
fine. 22—29. Very fine. 30. Fine: cloudy at night, and windy. $1. Rain:
fine, but cool at night.

Penzance.—August 1—3.Clear. 4,5.Fair. 6. Heavy showers. 7,8. Fair.
9. Showers. 10—12, Clear. 13—16. Fair. 17.Clear. 18. Fair:
showers. 19. Showers. 20—23. Clear. 24. Rain. 25.Fair. 26, Fair:
rain. 27. Misty. 28,29. Clear. 30.Fair. $1. Misty: rain.

This month has been unusually dry; the quantity of rain fallen is 1°8150
of an inch, which is less by 0°3000 of an inch than has fallen in the month
of ge during the last ten years, and 2:0757 below the average of that
period.

Boston.—August 1. Cloudy: rain at night. 2—4. Cloudy. 5. Rain:
thunder and lightning a.m.: rain all day. 6. Foggy. 7. Fine: rain, with
thunder and lightning p.m. 8. Cloudy. 9. Cloudy: rain at night.
10,11. Fine. 12.Cloudy. 13,15. Fine. 16, Cloudy: heavy rain, with
thunder and lightning. 17. Cloudy: rainr.m. 18. Fine. 19. Stermy:
rain early a.m. 20, Stormy: rain p.m. 21. Stormy. 22, 23. Fine.
24.Fine: rainer.m, 25,26.Fine. 27.Cloudy. 28—30, Fine. 31,Cloudy.

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THE

PHILOSOPHICAL MAGAZINE

AND

ANNALS OF PHILOSOPHY.

—

[NEW SERIES. ]
NOVEMBER 1831.

XLI. On Vanadium. By M. BErzexivs*.

ANADIUM was discovered in the year 1830 by Sef-
strom, in a Swedish iron, remarkable for its ductility,
obtained from the iron mine of Jaberg, not far from Jon-
koping in Sweden. The name of this metal is derived from
that of Vanadis, a Scandinavian divinity. It is not yet known
under what form, or in what state of combination, vanadium
occurs in the ore of Jaberg. It is also found in Mexico, in a
lead mine at Zimapan. Del Rio, who analysed this mineral
in 1801, announced the discovery of a new metal in it, which
he called Evythronium; but the same mineral having soon af-
terwards been analysed by Collet Descotils, he asserted that
erythronium was merely impure chromium. Del Rio himself
adopted the opinion of the French chemist, and considered
the mineral as a subchromate of lead; thus the metal, so near
being discovered, remained thirty years unknown to chemists.
Since the discovery of vanadium by Sefstrom, Wohler has as-
certained that the mineral of Zimapan contains vanadic and
not chromic acid.

I have had an opportunity of studying the properties of this
metal, and those of its combinations, by means of specimens
presented to me by M. Sefstrém for that purpose.

M. Sefstr6m having ascertained that the finery cinder of the
cast-iron of Jaberg contained more vanadium than the iron
itself, made use of it to obtain the metal, which occurs in it in
the state of vanadic acid. For this purpose he uses the fol-
lowing process: the finery cinder is powdered and mixed with

* Traité de Chimie, tom. iv. p. 642. See also the present volume of Phil.
Mag. and Annals, p. 151, 157, and 209; andthe Miscellaneous Articles in
the present Number.

N.S. Vol. 10. No, 59. Nov. 1831. yaa be nitre

322 M. Berzelius on Vanadium.

nitre and carbonate of soda, in the proportions of one part
of cinder, one of nitre and two parts of carbonate; this mix-
ture is strongly calcined for an hour. The soluble portion of
the powdered mass is dissolved by boiling water, the solution
is filtered, and the excess of alkali saturated with nitric acid
and afterwards precipitated with muriate of barytes or acetate
of lead. ‘The precipitate is vanadate of barytes or lead, con-
taining also some phosphate of barytes or lead, silica, zircon,
and alumina. Whilst it is still moist, it is to be decomposed
by concentrated sulphuric acid; the solution immediately be-
comes of a deep red colour, and after having digested the mix-
ture for half an hour, alcohol is added to it, and it is again
digested ; zether is then formed, and the vanadic acid i is re-
duced to the state of salifiable pele the solution of which is
blue; and when it begins to assume a syrupy consistence,
it is mnied in a platina crucible with a little fluoric acid to
separate a portion of silica, which it is almost impossible to
get rid of in any other manner; the evaporation is continued
over the naked fire, and the sulphuric acid is at last expelled
at a red heat. The residue is impure vanadic acid. It is
fused with nitre, added in small portions at a time. ‘The va-
nadic acid combines with the potash and expels the nitric
acid, and nitre is added until it is found that on cooling a
small portion of the mass it ceases to be red. The alkaline
carbonates may be employed ; but when nitre is used, the zir-
con and alumina remain less acted upon, when the vanadate
of potash is dissolved. ‘The mass is afterwards dissolved in
water, and after filtration the residue is slightly washed; it still
contains vanadium, and ought not to be thrown away. A piece
of sal ammoniac, larger than can be dissolved by it, is to be
put into the filtered liquor. As this salt dissolves, a white
pulverulent precipitate is formed, which is vanadate of am-
monia, insoluble in a saturated solution of sal ammoniac.
The phosphate of ammonia remains dissolved; but when the
solution is alkaline, which happens when a carbonate is em-
ployed to dissolve the vanadic acid, insoluble subphosphate
of ammonia always precipitates. ‘The vanadate of ammonia
ought to be washed, first with a solution of sal ammoniac,
and afterwards, to remove the sal ammoniac, with alcohol of
0°86. It is to be again dissolved in boiling water, mixed with
a little ammonia, filtered and left to crystallize. It is from
this salt that vanadic acid and oxide are afterwards obtained,
by heating it gently in open vessels to procure the former, me
in closed vessels to prepare the latter.
The residue which has been mentioned is a compound of
vanadic acid, alumina, zirconia and silica. ‘The vanadium is
extracted

M. Berzelius on Vanadium. 323

extracted from it by means of an alkaline hydrosulphuret, by
fusing the residue with sulphur and carbonate of potash. Sul-
phovanadate of potash is formed, from which sulphuret of
vanadium may be precipitated by sulphuric acid.

Vanadium is very difficult of reduction by the usual methods,
that is to say, by heating the oxide in a charcoal crucible ; for
it is reduced only at the places in which it is in immediate
contact with the charcoal, and the interior is a suboxide, as in-
fusible as the metal itself at the temperature at which man-
ganese undergoes fusion.

With potassium the reduction is easy; pieces of vanadic
acid, which have been previously fused, are to be mixed with
pieces of potassium of equal bulk in a porcelain crucible; the
cover is to be well fastened on, and the crucible is to be heated
with a spirit-lamp. The reduction occurs almost instantane-
ously with a kind of detonation. The crucible, when cold, is
to be put into water to dissolve the potash, and the reduced
vanadium is to be collected on a filter; it is obtained in the
state of a black powder, which shines in the sun, and takes a
grayish metallic lustre underthe burnisher. But in this way a
true idea of the aspect of the metal is no more obtained, than
of that of gold precipitated from solution by the salts of iron.

When the method discovered by M. Rose for the reduction
of titanium is employed to reduce vanadium, the experiment
succeeds more completely than with potassium. For this pur-
pose, chloride of vanadium is prepared, by passing a current
of dry chlorine over a mixture of vanadic acid and very dry
charcoal. This chloride is a volatile fuming fluid, and it is to
be introduced into a glass bulb blown on a barometer tube; a
current of dry ammoniacal gas is passed through the tube until
the chloride is entirely saturated. Sal ammoniac sublimes,
which may be expelled from the tube by another spirit-lamp.
The reduced vanadium remains in the bulb, and an inconsi-
derable portion is reduced at that part of the tube which is
kept hot. On cutting the bulb afterwards in two, the vanadium
is found in the state of a silvery white stratum, which on the
side next the glass reflects like a mirror, and is white like po-
lished steel. If water and atmospheric air are not entirely
excluded, a small quantity of black powder is found in the
middle of the mass; this is suboxide of vanadium, and is easily
detached.

Vanadium is white, and when its surface is polished it re-
sembles silver considerably, or molybdenum, which of all
metals it is most like. It is not ductile, and is easily reduced
to a powder of an iron-gray colour. I have not enough of it,
nor are my specimens in a convenient form, to determine its

: ih specific

324 M. Berzelius on Vanadium.

specific gravity. It is a good conductor of electricity, and
strongly negative to zinc. The powder of vanadium, obtained
by its reduction with potassium, takes fire at a heat below red-
ness, burns without energy, and leaves a black unfused oxide.
Vanadium dissolves readily in nitric acid and in aqua regia;
the solution has a fine blue colour. The sulphuric, muriatic,
and fluoric acids do not attack it at all, even when they are
concentrated and boiling. It is not oxidized by the alkaline
hydrates, and it may be heated with them to redness without
undergoing any alteration if the air be excluded. The solution
of vanadic oxide in the acids, or of vanadic acid in an excess
of caustic potash, does not give metallic vanadium by zine.

Oxides of Vanadium.—Of this metal there are three com-
pounds with oxygen :—

Ist, Suboxide of Vanadium.—It is obtained by reducing
vanadic acid by hydrogen gas at a red heat, or by fusing va-
nadic acid in a cavity made in charcoal. In the first mode,
the suboxide preserves the form and lustre of the crystalline
facets of the acid, but it becomes black; by the latter pro-
cess a coherent mass is obtained, which is easily reducible
to powder, possesses a semimetallic lustre and the colour of
plumbago. Hydrogen passed over the suboxide does not de-
compose it at the highest temperature which can be imparted
to it in a porcelain tube heated by a small wind-furnace.
This suboxide, by whatever process obtained, provided it be
coherent, is a good conductor of electricity, and infinitely ex-
ceeds copper, and even gold and platina, as a negative electro-
motor.

It has not hitherto been combined with other bodies, or
with acids or bases. That which is reduced by hydrogen gas
gradually oxidizes in the air, but without any alteration of ap-
pearance; and the lower the temperature at which the oxide
is formed, the more readily oxidation occurs. Its oxidation is
apparent by throwing it into water, which becomes of a fine
green colour by dissolving a compound presently to be treated
of. When heated in the air, it takes fire and burns, leaving
an unfused black residue. Chlorine gas converts it into
chloride and vanadic acid. It is composed of 89°538 parts
of vanadium, and 10°862 parts of oxygen; 100 parts of the
former are combined with 11-6843 parts of the latter.

2ndly, Oxide of Vanadium.—Vanadate of ammonia cannot
be employed in the preparation of this oxide in the same way
as the molybdate and tungstate of ammonia, which yield the
oxides of their metals when they are heated. The oxygenated
compound of vanadium obtained by this method, contains the
three degrees of oxidation of this metal. In order to obtain

pure

M. Berzelius on Vanadium. 325

pure oxide of vanadium in the dry way, 9°5 parts of suboxide
of vanadium are to be mixed with 11°5 parts of vanadic acid,
and the mixture is to be heated to whiteness, in an atmosphere
of carbonic acid gas. In the moist way, it may be obtained
by precipitating a blue vanadic salt, previously treated by
sulphuretted hydrogen, sugar or alcohol, in order to destroy
all the vanadic acid which it may contain. This solution is to
be precipitated by carbonate of soda, added slightly in excess.
A grayish white precipitate is formed, which is collected on a
filter and washed, without the contact of the air. It is to be
pressed between folds of filtering paper and dried in vacuo.
It is gray, inclining to brown: it is hydrated oxide of vana-
dium, sometimes containing traces of carbonic acid. When
heated to redness in vacuo, it yields water and leaves the oxide
in the state of a black powder, which does not blue litmus
paper that has been previously reddened. Oxide of vanadium
is not fusible at the temperature at which glass softens. It is
insoluble in water, but if it remains long in it the water becomes
gradually green, in consequence of increased oxidation. The
hydrate rapidly oxidizes in the air, and becomes first brown
and afterwards green; when dried it is black: it will be again
noticed. Oxide of vanadium which has been heated, dissolves
slowly but completely in acids; the solution is blue, and the
oxide acts as a base; but it combines with bases and forms
salts, which may be calied vanadites. ‘The alkaline carbonates
dissolve it; the solution, which is of a deep brown, contains a
vanadate and a bicarbonate; the bicarbonates also dissolve it,
and assume a blue colour: it appears that this solution con-
tains neutral double carbonate of vanadium and alkali. Oxide
of vanadium is composed of 81:056 parts of vanadium, and
18°944 of oxygen, or 100 parts of the metal combine with
23°369 parts of oxygen, that is to say, with twice as much as

in the suboxide.
3rdly, Vanadic Acid.—This is obtained by exposing vana-
date of ammonia to a heat near redness in an open platina
crucible, and stirring it occasionally. ‘The vanadate decom-
poses, becomes at first black, and afterwards, in proportion
as it absorbs atmospheric oxygen, of a red brown colour,
which, by cooling, becomes gradually pale, and finishes by
turning to a rust colour. ‘The finer the sal ammoniac is
powdered, the paler is the colour of the acid. The acid
thus obtained, when triturated, becomes of the colour of the
hydrate of iron, which forms on the surface of the metal im-
mersed in water. It is tasteless and inodorous; it reddens
the colour of moistened litmus paper. As soon as it is red
hot it fuses. In this state it sustains a white heat without
losing

326 M. Berzelius on Vanadium.

losing oxygen, if it be preserved from the influence of com-
bustible bodies. When fused it crystallizes on cooling, and
then exhibits a phenomenon, which merits observation. It
solidifies at a heat which is invisible in daylight ; but the mo-
ment that solidification commences, a luminous circle extends
from the periphery to the centre, where, owing to latent heat
becoming free, the mass remains red hot as long as the cry-
stallization continues. The acid contracts much on solidify-
ing, and is readily detached from the crucible: it is then of
a yellowish red colour, and formed entirely of a mass of inter-
laced crystals. Cavities frequently occur containing small and
perfectly regular crystals, the form and size of which may be
determined, when opportunity offers of repeating the experi-
ment with about 300 grains. Fused vanadic acid is translu-
cent at the edges, and has a yellowish colour. When it is
impure, or when it has been in part reduced to the state of
oxide, it does not crystallize; but at the moment of its solidi-
fication, excrescences are produced in the form of cauliflowers,
and the solidified mass is blackish. If the acid contains a
very small quantity of oxide, it crystallizes, but afterwards
assumes a violet colour. Vanadic acid is not a conductor of
electricity. It is slightly soluble in water, to which it imparts
a bright yellow colour. If the pulverulent acid be put into
water and well stirred, it mixes with it so as to produce a
turbid fluid of a yellow colour, which does not become clear
for several days: 1000 parts of boiling water scarcely dissolve
one part of vanadic acid, but the cooled solution remains trans-
parent. The acid is deposited by evaporation in the form
of red concentric rings. The last portion gives yellowish
microscopic crystals, but they become green when heated.
It is a compound of vanadic oxide and acid, produced appa-
rently by the influence of dust floating in the air; a pheno-
menon similar to the partial reduction of a solution of oxyman-
ganic acid, which is attributed to this cause. It is in general
impossible to crystallize vanadic acid in the humid way, and
it is equally so to extract it in an isolated state from a solution,
because it combines equally with acids and bases. _ It is easily
reduced to the state of oxide, especially under the influence
of an acid; red nitric acid, sulphurous acid, several vegetable
acids, especially the oxalic and tartaric, alcohol, sugar, &c.
effect this reduction at a moderate temperature. Muriatic
acid dissolves and becomes of an orange colour; but soon
afterwards chlorine is disengaged, and the solution then pos-
sesses the property of dissolving gold and platina. Vanadic
acid, fused on charcoal by the blowpipe, leaves a coherent
mass, of the colour of plumbago, which is the suboxide of

vanadium:

;

M. Berzelius on Vanadium. 327

vanadium: with the phosphate of ammonia and soda it gives
a fine green colour to glass, which appears brown while it is
hot. ‘The blue colour of the salts of vanadium cannot be pro-
duced, even on adding metallic tin to the flux. With borax’
it also gives a green glass. In this reaction vanadium resem-
bles chromium, but the green colour produced by the former
may be changed to yellow by the oxidating flame, which does
not happen with chromium. ‘This change is easily effected,
especially with the glass of borax. With carbonate of soda it
is not reduced to the metallic state. Vanadic acid is composed
of 74:0449 parts of vanadium and 25°9551 of oxygen, that is
to say, $5°0533 of the latter, and 100 of the former; conse-
quently the metal is combined with three times as much oxy-

en as in the suboxide. Its saturating capacity is equal to
one third of the quantity of oxygen which it contains, that is
to say, 8°6517.

4thly, Intermediate Oxides of Vanadium.—We have seen
that the suboxide and oxide of vanadium, when exposed to
the influence of the air, acquire the property of colouring
water green. The vanadic oxide and acid combine together
in different proportions; two of these compounds have the
property of forming with water a solution of a fine green co-
lour. Other compounds are purple and orange coloured.
They pass, by the influence of the air, from one degree of
oxidation to a higher one.

a. Purple Oxide.— If vanadic acid be kept for twenty-four
hours in a badly corked bottle, and water be then added to
it, it becomes of a green colour. The mass is then to be poured
upon a filter, and when the green liquor is filtered a fresh
portion of water is added; the fluid which then filters is much
deeper coloured and brownish; a fresh quantity of water
assumes a fine purple colour, and when the washings have
been thus continued for some time, the water passes through
colourless. The residue exposed for some time to the air
acquires the property of reproducing the phenomena which
have been described, and eventually a new purple liquid is ob-
tained. This solution holds but little matter in solution; it
may be preserved in a full bottle hermetically sealed, but on
exposure to the air it soon becomes green and afterwards yel-
low. The vanadic acid appears to be combined with the
greatest quantity of oxide of vanadium that it is capable of
rendering soluble. It may be called a subvanadate of vana-
dium.

b. Vanadate of Vanadium. — If hydrate of vanadium be
allowed to dry in the air, and then digested in a very small

quantity

328 M. Berzelius on Vanadium.

quantity of water, it becomes of a green colour, which is beau-
tiful, but so deep that the solution appeares opake. The solu-
tion, when filtered and evaporated zn vacuo, leaves a blackish
cracked residue, without any trace of crystallization, and which
is completely resoluble in water. This same combination is ob-
tained, when a solution of a neutral salt with a base of oxide of
vanadium is mixed with neutral vanadate of potash, If the
solutions are moderately concentrated, a great part of the new
green compound formed is deposited in the state of deep co-
loured powder; and if the solution is too dilute to give a
precipitate, one is obtained by dissolving sal ammoniac in it.
The precipitate is insoluble in absolute alcohol, but it dissolves
in alcohol of 0:86. The solutions of this substance diluted so
as to become perfectly transparent, have a very fine green
colour. A small quantity of alkali deepens the colour, but
does not destroy the green compound. The addition of a
caustic alkali in excess occasions in a short time a brown pre-
cipitate, which is a vanadate of the alkali added. ‘The carbo-
nates of soda and potash change the green colour to brown,
without precipitating anything; an excess of carbonate of
ammonia does not destroy the colour. Vanadic oxide, mixed
and digested with vanadic acid, forms the same compound,
which may also be produced in the dry way by heating an
intimate mixture of 10} parts of oxide, and 23-1, parts of va-
nadicacid. The mixture fuses, and gives a glass of a deep green
colour, the powder of which dissolves gradually in water.

c. Bivanadate of Vanadium.—This compound is obtained
by mixing a neutral salt of vanadium with one of bivanadate
of potash; this salt is solid and green like the preceding, the
tint of which is deeper; its solution in water is of yellowish
green. It is less soluble than the preceding, and is more com-
pletely precipitated by sal ammoniac.

d. Supervanadate of Vanadium.—All the purple and green
compounds oxidize in the air, especially when they are very
dilute. Their colour becomes first greenish yellow, and after-
wards orange yellow. By spontaneous evaporation, they yield
crystals of a pale orange yellow colour, which lose their water
and become green when heated in the fire; 22°5 parts of water
dissolve one part of this orange compound, consequently it is
much more soluble than vanadic acid alone.

Sulphurets of Vanadium.—The affinity of vanadium for sul-
phur is but weak at moderately high temperatures ; it may be
mixed with sulphur, and the mixture may be distilled without
undergoing combination; and even when it is heated to red-
ness in an atmosphere of sulphur, vanadium is not sulphu-

retted.

M. Berzelius on Vanadium. 329

retted. Nevertheless, there are several modes of obtaining
sulphurets of vanadium; hitherto, only two have been formed,
proportional-to the oxide and vanadic acid.

1. Sulphuret of Vanadium.—This is obtained in the dry way
by exposing suboxide of vanadium to a current of sulphuretted
hydrogen at a red heat. Water, hydrogen, and even sulphur
are disengaged, and the vanadium is slowly converted into a
sulphuret. This sulphuret is black; it becomes compact by
pressure; when burnished it has not a metallic lustre. Heated
in platina foil, it burns with a blue flame, and leaves upon the
platina a circular pellicle, which is translucent, blue at the cir-
cumference and purple nearer the sulphuret. Water does not
remove this pellicle, but it disappears at a red heat, leaving
minute drops of vanadic acid. In this state sulphuret of va-
nadium is entirely insoluble both in sulphuric and muriatic
acids, and in the caustic alkalies. Nitric acid converts it into
sulphate of vanadium.

The salts of vanadium are not decomposed by sulphuretted
hydrogen, but the hydrate and the salts of vanadium are con-
verted by the hydrosulphurets into sulpho-vanadates, which
dissolve in water; the solution has a rich purple colour. Acids
poured into these solutions occasion a brown precipitate, which
soon subsides and then appears black; it is the sulphuret of
vanadium: it may be washed and dried without undergoing
any alteration; it dissolves with a purple colour in the alkaline
hydro-sulphurets. ‘The alkaline carbonates also dissolve it
when boiling, but the colour of the solution is brownish yel-
low. he sulphuric and muriatic acids do not decompose it,
although the liquid from which it has been precipitated re-
tains a bluish tint, in consequence of the decomposition of a
small quantity of nascent sulphuret. It is composed of 68-023
parts of vanadium, and 31-977 parts of sulphur.

2. Supersulphuret of Vanadium.—The affinity of sulphur for
vanadium is so weak, that when a current of sulphuretted hy-
drogen is passed into an aqueous solution of vanadic acid, the
precipitate is merely oxide of vanadium intimately mixed with
sulphur, from which the acids separate the oxide without dis-
engaging sulphuretted hydrogen, and leave the sulphur. To
obtain the supersulphuret of vanadium, vanadic acid must be
dissolved in an alkaline hydro-sulphuret, or the solution of a
neutral vanadate of an alkali must be decomposed by sul-
phuretted hydrogen, and the sulphuret must be afterwards
precipitated by sulphuric or muriatic acid. The colour of the
precipitate is brown, but much less deep than that of the pre-
ceding sulphuret; and there is this peculiar circumstance at-
tending it, that at the time of the addition of the acid it de-

N.S. Vol. 10. No. 59. Nov. 1831. 2U composes

330 M. Berzelius on Vanadium.

composes a portion of the supersulphate of vanadium in its
nascent state, and much more than of the sulphuret under the
same circumstances. ‘lhe supersulphuret of vanadium may be
dried and kept without suffering any alteration ; it appears to
be black, but the powder is brown. At a high temperature
it yields sulphur, and is converted into sulphuret: it dissolves
in the same menstrua as the sulphuret, but its solutions have
a deep colour resembling that of strong beer. Sulphuric and
muriatic acid do not decompose it. It is composed of 58°647
parts of vanadium, and 41°353 of sulphur.

Phosphuret of Vanadium.—When vanadium is heated to
redness in an atmosphere of phosphorus in vapour, they do not
combine; but when phosphate of vanadium is heated to white-
ness in a charcoal crucible, it is reduced, and gives a porous,
gray, unfused mass, which may be compressed, and has then
the colour and lustre of plumbago.

Alloys of Vanadium.—This branch of the history of vana-
dium remains to be investigated. M. Sefstrom, who is prin-
cipally occupied with metallurgic researches, intends to make
it the subject of extensive investigation. ‘The experiments
which I have had an opportunity of making on the subject
prove that vanadium combines readily with other metals; it
is sufficient to fuse by the blowpipe on charcoal several me-
tallic vanadates, to reduce them to the state of alloys of vana-
dium; but in this case they are deprived of ductility. In ex-
periments upon vanadium, the surface of platina crucibles is
often alloyed with vanadium, which does not alter either the
colour or the metallic lustre of the platina; but when it is
afterwards heated to redness, the alloyed parts are covered
with a layer of fused vanadic acid which preserves them from
further oxidation. When they are heated to redness, and af-
terwards washed with potash (and this is repeated five or six
times), the vanadium is separated. Neither bisulphate of potash
nor borax mixed with nitre when melted in the crucible suc-
ceed so well. Ihave not found that the crucibles were in any
way injured.

Salts of Vanadium*.—The salts which contain oxide of
vanadium as a base are, with few exceptions, of a superb azure
blue colour when in solution. In the solid state and com-
bined with water, they are either of a deep or light blue colour,
and sometimes greenish. Without water they are generally
brown, and sometimes also green. Both the brown and green
salts give blue solutions. ‘Their taste is astringent and rather

* In this translation we have entirely neglected Berzelius’s newly in-
vented nomenclature. It has increased the difficulties of the science, with-
out adding one advantage, that we can perceive.—Epit.

sweetish,

M. Berzelius on Vanadium. 331

sweetish, like those of iron. The greater number of them are
soluble in water; the caustic alkalies occasion a precipitate,
which is at first of a grayish white colour, and which after-
wards becomes of a liver brown; an excess of alkali dissolves
the precipitate, producing a solution of a brown colour. Am-
monia added in excess gives a brown precipitate, and the li-
quid becomes colourless. ‘The carbonates occasion grayish-
white precipitates: sulphuretted hydrogen does not render
them turbid, but the hydrosulphurets occasion a black preci-
pitate, and when added in excess they redissolve it, occasion-
ing a fine purple colour; ferrocyanate of potash occasions a
lemon-yellow precipitate, which becomes green in the air.
Infusion of galls gives a precipitate of so deep a blue colour
that it appears black.

Chloride of Vanadium.—This salt has not been obtained in an
anhydrous state: it can only be formed by passing the vapour
of chloride of vanadium over a mixture of suboxide of vana-
dium and charcoal heated to redness: when sulphate of vana-
dium, dried as much as possible, is mixed with chloride of
potassium and fused, the mass contains nearly the whole of
the vanadium. It appears that the vanadium is converted into
acid at the expense of the sulphuric acid.

Chloride of vanadium (muriate ?) is very easily obtained in
combination with water. If vanadic acid is dissolved in con-
centrated muriatic acid and heated, chlorine is evolved; but
when it is digested with suboxide of vanadium or with vana-
dium, chloride is obtained free from chlorine. The same effect
is produced by adding to the solution a little sugar, sulphu-
retted hydrogen, or alcohol. The solution has a fine blue co-
lour. If, on the contrary, concentrated muriatic acid be poured
upon oxide of vanadium prepared by calcining vanadate of
ammonia in close vessels, a brownish black solution is obtained,
and a little chlorine is disengaged, owing to the decomposition
of a little vanadic acid. ‘The brown liquid, saturated as per-
fectly as possible with oxide, suffered to evaporate spon-
taneously, becomes concentrated to a certain point, but is not
rendered dry. Diluted with water, it retains its brown colour;
but when evaporated with heat, it becomes gradually completely
blue. This change takes place immediately when sulphuric
acid is added, even to the concentrated liquid; and in this
case neither precipitation nor the evolution of any gas occurs.
It appears that the brown chloride differs only from the blue,
in being in a different isomeric state, which the sulphuric acid
instantly changes. The blue chloride gradually concentrates,
and in thin layers it dries, leaving a brown varnish, which is
no longer perlectly soluble in water. Evaporated at a mode-

2U2 rate

332 M. Berzelius on Vanadium.

rate heat, it is entirely converted into this brown mass, which
is a subchloride. It gives no appearance of crystallization.
Concentrated chloride of vanadium may be mixed with ab-
solute alcohol without precipitation. Ammonia oceasions a
greenish gray precipitate, which may be washed without dis-
solving, and which appears to be a subchloride containing
ammonia.

Bromide of Vanadium.—This salt resembles the blue chlo-
ride in all respects. Hydrobromic acid dissolves anhydrous
oxide of vanadium, the solution is blue. The concentrated
bromide, mixed with absolute alcohol, becomes in a few se-
conds gelatinous, because the alcohol seizes the water ; but it
becomes liquid in proportion as the alcohol evaporates. When
dried it becomes brown, but it redissolves almost entirely in
water. Ammonia precipitates a greenish gray double chloride.

Iodide of Vanadium.—lIts solution is blue like that of the
preceding salts, but it becomes quickly green in the air. By
spontaneous evaporation it becomes a semi-fluid brown mass,
which when diluted is of a blackish brown colour. Sulphuric
acid then disengages iodine. It appears to contain a mixture
of vanadate of vanadium and of ioduretted iodide of vanadium.
I have not examined it very minutely.

Fluoride of Vanadium. — In solution it is blue, and when
dried brown, and redissolves in water. By spontaneous eva~
poration it becomes greenish and ofa syrupy consistence, and
greenish crystals are formed. In this state it is soluble in
absolute alcohol, which does not restore its original blue co-
lour; sulphuretted hydrogen easily produces this effect. ‘This
fluoride combines with the alkaline fluorides, with which it
forms salts of a light blue colour, very soluble in water, but
not in alcohol.

Filuo-silicate of Vanadium.—The solution is blue; when eva-
porated at 140° Fahrenheit it gives a spongy light blue co-
floured mass. By evaporation it becomes green, and resembles
the fluoride.

Cyanuret of Vanadium.— When hydrate of vanadium is
treated with hydrocyanic acid, it becomes brown, and it may
be washed without becoming green or dissolving. I afterwards
treated it with cyanuret of potassium; it dissolved, but the
solution left to spontaneous evaporation only gave vanadate of
potash, exhaling at the same time the odour of hydrocyanic
acid. The ferrocyanate of vanadium precipitates in a bulky
mass, of a fine lemon colour with a greenish tint. It is not
soluble in diluted acids; by exposure to the air it becomes of
a fine green; the perferrocyanate of vanadium precipitates in
a gelatinous mass of a yellowish green,

Sulphate

M. Berzelius on Vanadium. 333

Sulphate of Vanadium.—This salt is obtained by dissolving
vanadic acid or oxide (as obtained by the calcination of vana-
date of ammonia) in sulphuric acid, mixed with an equal
quantity of water, and by passing sulphuretted hydrogen into
the solution diluted with water, in order to reduce the last
traces of the vanadic acid dissolved. Oxalic acid may be used
for the same purpose; the liquid is to be evaporated until the
excess of sulphuric acid begins to concentrate; the salt is then
deposited in the form of a transparent crystalline crust of a
dirty blue colour. ‘The excess of acid is to be drained from
the salt, and then it is to be washed with absolute alcohol.
The salt gradually swells, and is reduced to a light crystalline
powder of an ultramarine blue colour; it is then washed with
alcohol, which it always renders of a blue colour, although
but a very small quantity is dissolved. It is afterwards dried
by being placed under a receiver, with a vessel containing
snlphuric acid or chloride of calcium. An essential difference
appears to exist between the salt which crystallizes in the
concentrated acid and the blue pulverulent salt; but I do not
know in what it consists. It is probable that the former is a
supersalt ; for the blue powder which I analysed is neutral
sulphate. In this state sulphate of vanadium appears but
slightly soluble in cold water; it first diffuses itself through
it, and dissolves with extreme slowness, but in hot water it
dissolves readily: the supersulphate is deliquescent in warm
moist air, and becomes of a syrupy consistence; while the same
quantity of sulphate, kept under water, remains almost en-
tirely insoluble. It is rather difficult to obtain this salt in
regular crystals.

The best method of crystallizing it is to let the dry sulphate
deliquesce, and to suffer it to remain for some weeks. A very
slight excess of acid often favours the experiment, which
never succeeds in moist weather. The crystals consist prin-
cipally of an aggregation of prisms; but I obtained some
which were very short simple right prisms with rhombic bases,
having small triangular oblique facets at the summit of each
acute angle. Their colour resembles the fine blue of sulphate
of copper, but is perhaps rather deeper. This salt contains
17-9 per cent. of water, the oxygen of which is to that of
the base as 2 to 1. This also is the composition of the pow-
der precipitated by alcohol. Sulphate of vanadium is decom-
posed by heat; the oxide is converted into vanadic acid at
the expense of the sulphuric acid; sulphurous and anhydrous
sulphuric acid are disengaged, and fused vanadie acid re-
mains. If hydrate of vanadium be digested in a slightly con-
centrated solution of the sulphate, the hydrate is dissolved,

and

$34 ._ M. Berzelius on Vanadium.

and a soluble subsalt is obtained, which dries by spontaneous
evaporation into a blue transparent varnish, which becomes
brown and loses water when heated to 212° Fahrenheit. The
water redissolves it; but the solution exposed for a long time
to the influence of the air becomes green, and the salt is
eventually converted into vanadate of vanadium, which is de-
posited, and leaves the neutral blue salt in the state of a con-
centrated solution.

Sulphate of Vanadium and Potash. — This is obtained by
mixing, in proper proportions, the solutions of the two neutral
salts. ‘The double salt does not crystallize, but dries into a
gummy mass, of a light blue colour, which contains no trace
of crystallization.

Nitrate of Vanadium.—Nitric acid dissolves vanadium, its
oxide and suboxide; the solution has a blue colour, which is
not altered by boiling: but when hydrate of vanadium is dis-
solved to saturation in nitric acid, and the solution is suffered
to crystallize spontaneously, it becomes green when it has ac-
quired a certain degree of concentration, and at the instant of
complete desiccation the acid decomposes and leaves vanadic
acid, which retains a small quantity of combined nitric acid.

Phosphate of Vanadium.— The neutral salt gives a blue
syrup, which does not crystallize, and which, when dried with
heat, becomes white and swells like alum dried in the fire.
At a white heat it becomes round and agglomerates, but it
does not fuse. It is then of a deep colour, and completely
insoluble in water. The phosphate may be obtained in very
small blue crystals by mixing it with a certain excess of
phosphoric acid, and evaporating the solution at the tempera-
ture of 123° Fahrenheit. After some time the neutral salt is
found crystallized in the midst of a colourless mother-water,
which is merely concentrated phosphoric acid; it may be
afterwards removed by alcohol. In the air these crystals ra-
pidly deliquesce; when a concentrated solution of phosphate of
vanadium is mixed with absolute alcohol, a grayish blue gela-
tinous precipitate is formed, which when washed with alcohol
and dried is almost white, and does not alter in the air. It does
not completely dissolve in water, and appears to be a subsalt.

Arseniate of Vanadium.—-A solution of this salt containing
an excess of arsenic acid gives by evaporation a crust com-
posed of small crystalline grains of a light blue colour, which
may be deprived readily of the excess of acid by washing
with water. It dissolves so very slowly even in hot water
acidulated with arsenic acid, that it might be thought inso-
luble; water, nevertheless, is capable of holding much of it in
solution. Muriatic acid dissolves the crystals readily. If aoe

aci

M. Berzelius on Vanadium. 335

acid be saturated with hydrate of vanadium, a very concen-
trated solution is obtained, which furnishes by evaporation a
crystallized neutral salt, and also a gummy mass which appears
to be a subsalt. Alcohol acts upon the arseniate in the same
manner as upon the phosphate.

Borate of Vanadium.—A solution of borax precipitates the
salts of vanadium of a brownish gray colour. ‘This precipi-
tate is dissolved by an excess of boracic acid. ‘The solution
is blue, but it soon becomes green in the air. If an attempt
is made to restore the blue colour by passing a current of sul-
phuretted hydrogen into it, oxide of vanadium and subsul-
phuret are formed, which remain dissolved in the boracic
acid, and colour the solution of an intense brown. Sulphuric
acid quickly precipitates this solution, and the precipitate
consists of subsulphuret of vanadium. Subjected to spon-
taneous evaporation in the air, the solution soon becomes
green, and leaves at last a solid mixture, of a greenish brown
colour, of sulphate and vanadate of vanadium, sulphur, and
boracic acid in crystalline scales.

Carbonate of Vanadium.—It appears that this salt cannot be
obtained in the moist way. I have stated above that the pre-
cipitate formed by the alkaline carbonates in the salts of vana-
dium consists of hydrate free from carbonic acid, or contains
only traces of it; the presence of carbonic acid depends upon
accidental circumstances, as happens with the oxides of cobalt
and nickel.

Silicated Vanadium.— Prepared by double decomposition ;
this salt forms a greyish precipitate, which becomes green by
drying. Water does not separate anything from the green
powder.

Molybdate of Vanadium.— When sulphate of vanadium is
mixed with molybdate of ammonia, both in solution, a liquid
of a fine purple colour is obtained similar to that of tungstate
of molybdenum. On this account I imagined that there was
an exchange of oxygen, and that vanadate of molybdenum was
formed. But when a molybdate is mixed with vanadate of
ammonia, it becomes yellow and not purple. ‘The purple
colour disappears gradually in the air; it is at first replaced by
blue, then by green, and lastly by yellow, without the solution
becoming turbid. :

Tungstate of Vanadium.—This salt is precipitated in the
form of a brownish yellow powder. It dissolves in a sufficient
quantity of water, and when it is left in the liquid it dissolves
without the addition of water, in proportion as the oxide of
vanadium acidifies. The solution eventually contains a yellow

combination of the two acids.
Chromate

336 M. Berzelius on Vanadium.

Chromate of Vanadium.—Chromic acid dissolves hydrate of
vanadium. ‘The solution is of a brownish yellow colour, and
by spontaneous evaporation. leaves a brown polished varnish,
without any trace of crystallization. This varnish does not
completely redissolve in water, and the fresh solution is yel-
low. Sulphuretted hydrogen precipitates a greenish mass,
and the liquid becomes colourless.

Oxalate of Vanadium.— Oxalic acid saturated with hydrate
of vanadium, and evaporated, gives a blue varnish, which is
transparent and dissolves slowly in cold water, but more
readily in warm water. ‘This salt mixed with oxalic acid gives
a blue crystalline salt, which is very soluble in water. It re-
mains to be determined whether the first is a neutral or sub-
salt, and whether the second is, as it appears to be, a super-
salt.

Tartrate of Vanadium.—This salt is of a light blue colour,
the remarkable beauty of which is derived from its not be-
coming green by contact with the air. In the dry state it
forms a transparent splintery mass, which requires many hours
for solution in cold water, but hot water dissolves it more
readily. Ammonia dissolves it; the solution has a fine purple
colour, which it loses by the acidification of the oxide of vana-
dium when it is exposed to the air.

Oxalate of Vanadium and Potash.—This salt gives a blue
mass, which does not crystallize. Oxalic acid and the bin-
oxalates decompose vanadic acid, and form blue salts of vana-
dium.

Tartrate of Vanadium and Potash. — This salt has the ap-
pearance of a splintery extractive mass; its colour is blue with
a strong shade of violet. It may be obtained also by dissolv-
ing vanadic acid by means of bitartrate of potash: in this case
part of the tartaric acid is decomposed. Ammonia does not
precipitate the double tartrate, but it imparts to it a magni-
ficent purple colour, which is destroyed by the action of the
air.

Citrate of Vanadium.— This salt is uncrystallizable, and
gives a splintery mass of a very deep blue colour. It redissolves
slowly in cold water; the solution is of a pure blue colour.
Ammonia dissolves it, and assumes a yellowish brown colour,
which gradually disappears by oxidation when exposed to
the air.

Acetate of Vanadium. — Dilute acetic acid dissolves very
little hydrate of vanadium. The liquid is of a pale blue colour,
and yields a deposit when suffered to evaporate spontaneously;
this is a white powder, whilst the excess of acid evaporates.
When evaporated in a stove it becomes green, and the resi-

duum

Mr. Nixon on the Instrumental Error of his Horizon-Sector. 337

duum is no longer soluble even in concentrated acetic acid.
Acetate of potash does not precipitate the salts of vanadium.
Concentrated acetic acid dissolves hydrate of vanadium, but
the solution becomes green by spontaneous evaporation, and
leaves a granular powder, composed of deep green opake
microscopic crystals, the form of which is either a cube or a
very short rectangular prism; they dissolve very slowly in
water; the solution is of a deep green colour.

Formiate of Vanadium. — Artificial formic acid dissolves
hydrate of vanadium, and gives by spontaneous evaporation
a blue, opake, saline mass, which is easily soluble in cold
water; but this solution, which contains no excess of water,
becomes gradually green by contact with the air. ‘The salt
when perfectly dried is of a violet colour, with a tint of brown,
and is not completely soluble in water.

Succinate of Vanadium.—Succinic acid dissolves very little
hydrate of vanadium; the solution is but slightly coloured.
By evaporation the succinate is obtained in the state of a
white powder, mixed with crystals of succinic acid. Neverthe-
less, the salts of vanadium are not precipitated by neutral suc-
cinates, but the mixture soon becomes greenish.

Benzoate of Vanadium.—A boiling solution of benzoic acid
dissolves a little hydrate of vanadium; submitted to a slow
evaporation the solution deposits a yellow powder, and the
excess of acid crystallizes around it.

[To be continued. ]

XLII. Particulars of the Measurement, by various Methods,
of the Instrumental Error of the Horizon-Sector described in
Phil. Mag. vol. lix. By Joun Nixon, Esq.

[Continued from page 96. ]
By the Eleventh Method.
Theory.— [ET E (next page) represent the eye end, and O

the object-glass end of the (horizontal line) of col-

limation of a perfect telescopic-level (or of the horizon-sector)
correctly adjusted for taking a level. If we increase the diame-
ter of the cylindrical ring nearest the object-glass, by for in-
stance coiling a quantity of thread about it, the line of collima-
tion will be elevated in the direction FP; and on reversing the
telescope within its Ys, it will be equally elevated in the op-~
posite direction, or GQ*; the angle PEO = QOE being
* Admitting the Ys to have the same angular opening; but it is evident

from the demonstration given in page 429 of last volume, that were the
Ys unequal the theory would be equally applicable.

N.S. Vol. 10. No. 59. Nov. 1831. 2X the

338 Mr. Nixon on the Measurement of the

the instrumental error. Then if we place a second or proof
telescope with its object-glass nearly in contact with that of

the imperfect telescopic-level P, and make their lines of col-
limation parallel to each other, we shall find, on reversing the
latter, that the line of collimation of an object-glass substi-
tuted for the eye-tube E will be inclined to that of the proof
telescope HR by ¢wvce the instrumental error. As the rays
of light from the intersecting point of the cross wires of the
telescopic-level pass out of the additional object-glass into
that of the proof telescope parallel to each other, make Q'/R
parallel to QO, and Q'RE will be double the angle PEO =
QOE. Or, more simply, if we make E/O! parallel? to the
horizontal line EO, the line QR is elevated, and RE de-
pressed by an angle equal to the instrumental error.

Description of the Apparatus.

On an oak table (A) 3°5 feet long and 2 feet broad, which
stood against the eastern wall of a long room having but one

North

window (to the south), was placed a deal plank (B) 6 feet
long, 3°5 inches broad, and very nearly 6 inches thick, or
high; equal lengths of the plank overhanging each end of
the table. To prevent the plank upsetting, a bar of wood
about a foot long and 3 inches square, was fixed to each side
of it, their bases being slightly elevated above that of the plank,
that the latter might not bend by the bars coming in contact
with the table.

Two blocks of wood (CC) 3°5 inches high, 2°5 inches
broad, and of the length of the breadth of the plank, were
glued to its upper surface, one at a distance of 6 inches, and
the other at that of 17 inches from its south end. Firmly glued
to these blocks, stood an achromatic telescope set in a stout

mahogany

Instrumental Error of his Horizon-Sector. 339

mahogany frame (D) about two feet long and 2°5 inches
square, each end of the frame projecting equally beyond its
subjacent block. The sidereal focus of the object-glass was
full 20 inches, forming with the eye-tube a total focal length
of nearly 30 inches. Within the eye-tube, between the first
and second glasses, was placed a stop containing a vertical
slip of very thin mother-of-pearl divided on one edge by
fine horizontal lines into equal parts of about 1! 20" each,
together with two fine spider threads crossing each other, a
few seconds to the east, and in the plane of the slip of pearl, at
an inclination to the horizon of about 30°. By means of
the micrometer screw
(H), worked by the
milled head-nut (F)
placed outside the
tube, the intersecting
point of the threads
could be gradually
moved upwards or
downwards, parallel
to the divided edge
of the fixed slip of
pearl. The handle
(G) served to slide
the whole apparatus,
parallel to the sides
of the eye-tube, to
that distance from
the eye-glass at which
the threads appeared
most distinct. Four screws, with sliding slips of brass be-
neath their heads (of which two (I I) are represented in the
diagram), were used in the usual manner to alter the situation
of the point of intersection of the threads.

The proper object-glass (1) of the sector, fitting tightly
within the thicker end of the cylinder, is 13-1 inches in focal
length, and protrudes about 2 inches beyond the cylinder.
Within the opposite end of the cylinder, the eye-piece being
withdrawn, was fixed an additional object-glass (J) of 10°3
inches focal length, protruding about 4 inches. ‘The stop
containing the (adjustable) horizontal and vertical wires is
fixed within the cylinder, and was made the joint or common
focus of the two object-glasses. The sector being placed about
the middle of the length of the plank, with its cylinder nearly
on a level, and in a line with the telescope (D), the stand of
the sector was moved laterally until the vertical wire of the

2 cylinder,

340 Mr. Nixon on the Measurement of the

cylinder, as seen through the telescope, appeared to be bi-
sected by the intersecting point of the threads of the latter.
This being effected, the stand was glued at the sides (only) to
the surface of the plank, and the slight deviation in the bi-
section of the wire, occasioned by the setting of the glue, recti-
fied by the lateral adjusting screws (I I) of the telescope.

Illumination of the Wires. —In the daytime a square foot of
white pasteboard set up on the plank at a distance of about
six inches from the northern object-glass of the cylinder, was
so inclined as to reflect the light from the window up the cy-
linder and telescope. At night, or on a gloomy day, the
lantern (M) of a transit instrument was substituted, and so
situated that the tube (N) containing the lens was of the
height and in a line with the cylinder and telescope. In lieu
of a lamp, a white wax taper, about one-third of an inch thick
and five inches long, was fixed within the socket of the lantern,
the summit of the taper standing an inch or two above the
level of the lens-tube (N). The wires of the cylinder and
threads of the telescope could now be seen, on looking through
the eye-glass of the latter, with the utmost distinctness in
front of the pale taper mildly illuminated by the light reflected
from the tinned sides of the lantern. When the taper had
burnt down nearly to the level of the lens-tube, the light be-
came so intense that the wires appeared to split; and, on
the other hand, when the taper stood too high, they looked
dim and ill defined. In general, whether the lantern or paste-
board was used, a piece of black cloth was thrown loosely over
the object-glass of the telescope and the adjacent one of the
cylinder, its loose folds being so arranged as to exclude all
light, except that which passed through the further object-
glass of the cylinder.

Adjustment of the Wires to the Sidereal Focus. —'The tele-
scope, previously to its.being glued to the plank, was pointed,
when the ground was covered with snow, to some park rail-
ings at a distance of several miles, and the eye-tube pushed
in or drawn out until the railings could be seen with the
greatest distinctness*. The telescope being then considered
as properly adjusted, the spider threads were moved by the
handle (G) to such a distance from the eye-glass as produced
the clearest vision of the minute particles of dust adhering to
their sides. To confirm the accuracy of the latter adjustment,
the lantern was placed a little beyond the eye-glass, and the
threads viewed through the object-glass by an excellent 20-
inch (military) achromatic by Dollond, of which the sidereal

* The telescope could not conveniently be adjusted upon a star.
focus

Instrumental Error of his Horizon-Sector. 341

focus had been ascertained in the way described. On com-
mencing the verification, the latter was placed, purposely, out
of focus, but when altered so as to produce distinct vision of
the threads, its eye-tube was found, on every trial, to be at the
circle marking the sidereal focus.

The object-glasses within the cylinder were placed at a di-
stance from the cross wires fixed between them equal to their
respective sidereal foci (the cylinder and telescope being si-
tuated as represented in the figure, p. 338) by drawing out or
pushing in the tube containing the proper object-glass of the
cylinder, until the wires, as viewed through the telescope, ap-
peared as distinct as possible. The cylinder being reversed,
the additional object-glass, now brought close to that of the
telescope, was similarly adjusted.

(New) Method of setting a Wire vertical.— The uppermost
(L) of the transverse levels of the cylinder having its bubble
at the mark, the slip of pearl had its divided edge rendered
parallel to the upright wire of the cylinder by unscrewing in
a very slight degree the eye-tube containing it*. The cylin-
der was then reversed within its Ys, and the bubble of the
transverse level brought to its mark by turning the cylinder
within its Ys. On looking through the telescope, if the slip
and wire were found parallel, both were considered as perpen-
dicular ; otherwise one half. of the deviation was corrected in
the slip and the other in the wire, the bubble of the deranged
level being in the last place restored to its mark by its ad-
justing nuts. After the cylinder had been inverted and the
wire placed parallel to the (undisturbed) slip, the other trans-
verse level was similarly adjusted. In setting the lines of col-
limation parallel, or in reading off the great levels during the
subsequent observations, the bubble of the transverse level
uppermost was carefully kept to its marks.

Reference-Level.— The horizontal piece of brass (K) in
which works that part of the screw situated between its head
and the threads was so thin as to be elastic, thus rendering the
measurements made with the micrometer discordant and un-
certain. Recourse was therefore had to the great levels of the
sector (omitted in the figure), not however without reluctance,
the unsteadiness of the floor now requiring the addition to the
apparatus of a reference-level. ‘To the upper surface of the
westernmost (O) cf the pieces of wood projecting from the
sides of the plank was fixed a bar of oak (P) with its eastern
side glued to the plank. ‘The bar was mounted with a spirit-

* The slip being only a few seconds distant from the intersection of the
threads, the eye could estimate the parallelism with sufficient accuracy.

level

342 Mr. Nixon on the Measurement of the

level tube (having a scale of ,),th of an inch for 1") placed
parallel to the sides of the plank; and no measurements were
made by the great levels until the ends of the bubble of the
reference-level were brought, by an alteration of the situation
of the observer, to be stationary between two certain divisions
of its scale.

(New) Verification of the Adjustments of the Foci. — It has
already been stated that the cylinder and telescope were placed
on the plank in a line, and devel with each other. In this po-
sition, before the stand of the sector was glued to the plank,
the line of collimation of the telescope was made parallel to
that of the proper object-glass of the cylinder (that is, the in-
tersection of the wires of the cylinder appeared to be in a line
with, or intercepted by the intersection of the threads of the
telescope); when first one and then, on inverting the cylinder,
the other great level were carefully read off. In the next place,
the stand of the sector was taken off the plank, and replaced
with a board 0°85 inch thick, introduced between it and the
plank. The cylinder being now raised nearly an inch above
the level of the telescope, their lines of collimation were once
more made parallel, and the great levels again read off*. ‘The
results were:

Bubble. Bubble.

\ 42°; 113° Left do. 33°; 123°
312; 1223

Sector-stand placed on
plank; right hand level
Ditto on removal of board... 404; 1304

Mean 414;1312 —— 324; 123

Sector-stand placed on board 41; 131 — 33;123
(The divisions of the scales are about 2" each.)

Flexibility of the Plank.—As one end of the cylinder was
very probably a few ounces heavier than the other, the distri-
bution of gravity might be sensibly varied, in case the flexure
of the plank was considerable, on reversing the cylinder
within its Ys. As a two-pound weight could however be
placed on any part of the plank without affecting the paral-
lelism of the lines of collimation, its flexibility was undoubtedly
too slight to vitiate the measurements. But on fixing a se-

* With Kater’s horizontal floating collimator the parallelism of the rays
might be elegantly demonstrated. Point the wires of a telescope having
a very large object-glass exactly at those of the ccllimator, the telescope
being placed as much as possible above the level of the collimator without
losing sight of its wires. The tube of the collimator may now be raised
several inches in level by gradually augmenting the quantity of quicksilver
within the trough, yet without disturbing the apparent interception of the
wires of the collimator by those of the telescope.

cond

Instrumental Error of his Horizon-Sector. 343

cond telescope at the northern extremity of the plank as a
counterpoise to the one at the opposite end, and introducing
a narrow bar of wood between the table and the plank, on
which the latter would altogether rest without touching the
table, the cross of the threads of the telescope, which had
been previously set to bisect the horizontal wire of the cy-
linder, was found to have started from it to the amount of
several seconds.

Process of Measurement. — The line of collimation of the
proper object-glass of the cylinder having been made pa-
rallel to the axis of the latter (which was easily and most
accurately effected by the cross threads of the telescope), it
was then made parallel to that of the telescope by elevating
or depressing the cylinder by means of the rack-work of the
stand, rather than by the more expeditious, yet uncertain ap-
plication of the micrometer, which, with a view to insure its
steadiness, had been long undisturbed. In the next place,
by reversing the cylinder within its Ys, the additional object-
glass was brought close to that of the telescope, when its line
of collimation was found to be so nearly parallel to that of the
telescope, that it could be rendered Jevel with it by unscrewing
a little the additional object-glass, which was not well centred,
within its cell. This effected, the cylinder was inverted within
its Ys, and on looking through the telescope, the intersection
of the wires of the cylinder appeared above the level, and con-
siderably to the right of the point of intersection of the threads
of the telescope. To measure the difference of Jevel of these
two points of instersection, evidently equal to the quadruple of
the instrumental error, both the great levels were read off;
then the horizontal wire of the cylinder being brought by the
rack-work of the stand to the level of the intersecting point
of the threads of the telescope (by which it appeared to be
bisected), the reading off of the levels was repeated. Ex-
ample, February 9th, 1830.

Cylinder reversed ; additional object-glass and that of tele-
scope together.

Bubble.

Right-hand level (scale, 1° = 175) «..... 464°; 136°}

Left-hand level (scale, 1° = 1°92) ...... 50 3 141
The line of collimation of the telescope level with the hori-

zontal wire of cylinder. Bubble.
Right-hand level ........ccececccccccscceees 19°F; 109°F
Left-hand 16vel siscnsccsssccesccccqvesesccocs 254; 1164

To confirm the measurements the cylinder was again re-
versed, which brought the proper object-glass of the cylinder
close

344 Mr. Nixon on the Measurement of the

close to that of the telescope. The levels were then noted
before and after the parallelism of the lines of collimation had
been effected.

When the line of collimation of the proof object-glass had
been made parallel to, or more correctly, /evel with that of the
telescope by unscrewing it within its cell, the cross wires of the
cylinder intersected each other at
E, about 1’ to the west of C, or point
in which they were situated pre-
viously to reversing the cylinder ;
but on turning the cylinder half
round within its Ys, the intersec-
tion was removed to D, about 11’
east of C. The axis of the (re-
versed) cylinder, situated at F,
must therefore have been about
6' out of its previous direction; a
consequence either of the Ys being
of an irregular figure, or of the cylinder not being straight.
Two systems of cross wires, one for each object-glass, would
certainly have been preferable.

Having discovered that the tube containing the additional
object-glass did not fit sufficiently tight within the cylinder,
beyond which it projected considerably, the evil was remedied
by applying glue to fix it. Still there existed some degree
of doubt whether the tube was not sensibly deflected by its
own weight.

The average of twenty-five measurements in April 1829,
and January and February 1830, with the room constantly at
45° Fahr., made the instrumental error between 12-0 and
i6"-6, mean 13-8. Those of 1829 were made before the
present object-glass of the cylinder was substituted for the
original one of greater focal length, on a plank 5°5 feet long,
5 inches broad, but only 3 inches thick. The average of
these (four) measurements was 14!*1.

By the Eleventh Method varied.— With an efficient micro~
meter, a more simple or accurate method than the one just
described could scarcely be devised. However, as the error
was of necessity to be determined by the spirit-level, the mea-
surements were repeated with such improvements in the ap-
paratus and variations of the method as promised the most
successful results.

Two iron brackets, driven, at a distance of 30 inches from
each other, into a seam of the stone wall forming the east side

of the room, and from which they projected nearly a foot,
supported

Instrumental Evror of his Horizon-Sector. 345

supported a deal plank 44 feet long, 5 inches broad, and 3
inches thick, secured to them at a distance of 4 inches from
the wall *.

To the upper surface of the plank, planed as horizontal as
possible, was glued towards its northern end the stand of the
sector. The cylinder contained, as before, its own and an
additional object-glass, but the latter was more effectually
fastened within it at the slit used for the eye-tube by two broad-
headed screws driven in at some distance from each other.
South of the sector stood the telescope, moveable, with the two
blocks of wood to which it was glued, along the surface of the
plank. Into its upper surface were screwed parallel to its sides
the brass Ys of the proof-level, carrying Fortin’s level-tube.

As the plank did not prove perfectly steady, a mahogany
bar, mounted with two brass Ys supporting a level-tube, was
glued to its surface parallel and nearly close to the western
side of the sector-stand. ‘The tube, 14 inches in length and
one in diameter, had a scale of ;!,th inch to 2", With the aid
of this reference-level the minute inclination given to the
plank by moving the telescope along it could be detected,
and readily corrected by placing one or more light weights
upon a proper part of the plank.

As the axis of the reversed cylinder could not be made
parallel to the line of collimation of the additional object-glass
without disturbing the cross wires of the cylinder, it was of
the utmost importance that one of the latter, when the bubble
of either transverse level stood at its marks, should be truly
horizontal. After this had been effected as correctly as was
practicable by the former plan, the telescope was pointed first
at one and afterwards at the other extremity of the wire;
Fortin’s level being noted in both instances. ‘The inclination
of the line being proved by the slight difference observed in
the two readings, it was gradually altered until it would endure
this severe test. The cylinder being inverted, the other trans-
verse level underwent a similar scrutiny.

As the pearl slip was of unquestionable steadiness, one of
its divisions was substituted for the cross threads of the tele-
scope, and could be brought with rigid accuracy to be in a
line or level with the horizontal wire of the cylinder, by gra-
dually withdrawing from beneath one of the blocks fixed to
the telescope a sheet of thin paper previously introduced be-
tween the plank and block. At the same time the vertical
wire of the cylinder, as dimly seen through the diaphanous
pearl, divided the slip into two equal vertical sections.

* Suggested by Captain Kater in his description of the floating colli-
mator.

N. S. Vol. 10. No. 59, Nov. 1831. 2Y Method

846 Mr. Nixon on the Measurement of the

Method of Observation.—The telescope being in a line with
and of the height of the cylinder, with the proper object-glass
of the latter at a short distance from that of the telescope, the
division of the pearl slip was got in a line with the horizontal
wire of the cylinder, before, and (as an additional precaution)
after the cylinder had been inverted; the reading of Fortin’s
level following each observation. The cylinder being reversed,
the telescope was moved southwards until its object-glass stood
at the proper distance from the additional object-glass; when
the process of making the division of the slip level with the
wire previous and subsequent to inverting the cylinder, to-
gether with the simultaneous noting of Fortin’s level, was re-
peated. (It is almost superfluous to state that the latter was
never read off until the bubble of the reference-Jevel stood be-
tween its marks.)

There were now sufficient data to determine the difference
of inclination of the axis of the cylinder resulting from the
latter being reversed within its Ys; which difference it has
been demonstrated is equal to double the instrumental error.

To prove that the great excentricity of the additional ebject-
glass did not vitiate the results, the two last measurements
(marked in the subjoined list with an asterisk) were made with
the line of collimation of the additional object-glass rendered
parallel to the axis of the cylinder, on reversing it within its
Ys, by altering the cross wires with the utmost care.

List of the Results of the Measurements.
April 8th, 1831. Temp. 57°. Error = 13!*2

—_- —- — Sp AE Conga
—S> oo ——-- 582 —— «=13°7
—- | —«§» —— 59 - —— += i116
April-Sth,' 183i.) N56 Se gag
BY gin a 62 te 1
— 63 13 *3*

The mean of the whole is 12!8, but if we reject the fourth
measurement it will become 13!'*1.

By the Tenth Method.

Theory.—Having demonstrated that the axis of the faulty
cylinder deviates, when reversed, from the opposite of its
previous direction by double the instrumental error, it is evi-
dent that the line of collimation of a telescope made parallel to
the axis of the cylinder before, and that of another telescope
made parallel to it after the reversing took place, would be
inclined to each other by twice the error.

Apparatus.—In addition to the apparatus first employed,
two

Instrumental Error of his Horizon-Sector. 347

two substantial blocks of wood were glued, nine inches asun-
der, to the upper surface of the plank towards its northern
end; (occupying the place of the lantern as represented in the
figure, p. 338.) These blocks, notched in the middle in a line
with the cylinder and telescope, supported, on a level with the
two latter, a tube of wood 14 inches long and 1°5 inch in dia-
meter, containing within its southern end the additional ob-
ject-glass and tube, and a fine eye-piece (by Dollond) within
the northern end. Distinct vision of the cross lines, fixed at
right angles to each other, between the first and second glasses
of the eye-tube, being obtained by regulating their distance
from the moveable eye-glass, the object-glass was adjusted to
the proper focus by pointing the tube (telescope) at the sails
of a distant windmill.

Method of Observation.—The cylinder being removed, its
place within the Ys was supplied by a tin tube (of the same
diameter) blackened within, which reached so nearly from the
object-glass of one telescope to that of the other that all false
light could be excluded by a large piece of black cloth cover-
ing the tube and object-glasses. Having placed the lantern
a little beyond the eye-glass of the round telescope, the inter-
secting point of the cross threads of the square telescope were
moved by their micrometer screw until they bisected the ho-
rizontal wire of the round telescope where crossed by the ver-
tical one. Removing the lantern to beyond the eye-glass of
the square telescope, the bisection, on looking through the
round telescope, did not appear quite perfect or certain, being
slightly affected by evident parallax.

Lastly; the cylinder containing its proper object-glass only,
being substituted for the removed tin tube, the line of colli-
mation of its object-glass, which was situated close to that of
the round telescope, was made parallel by the rack-work of
the stand to that of the latter; or rather, as nearly so as the
almost impossibility of placing one wire exactly before another
would admit of. The cylinder being reversed, the great levels
were read off, before, and then again after the line of collima-
tion of its object-glass had been made parallel, by the rack-
work of the stand, to that of the square telescope. In making
the bisections, the lamp stood on separate apparatus near
the eye-glass of the opposite telescope.

The results (scarcely worth transcribing) varied in eighteen
measurements from 15-5 to 27-5; mean 21-3, or 8” more
than by the Lleventh method.

Joun Nixon.
{To be continued.]

2Y 2 XLIIL. Notice

f. 948) J

XLIII. Notice on Ovalic Acid. By Euwarv Turner, M.D.
F.RS. L. & E. &c., Professor of Chemistry in the University
of London*.

N a former Number of this Journal+ I had occasion to
publish some remarks on the volatility of oxalic acid; and
about the same time M. Gay-Lussac published in the Annales
de Chimie et de Physique, vol. xlvi. p. 218, a short memoir on
the easy decomposition of oxalic acid by the agency of heatt.
In my notice the sublimed acid is described as supporting a
temperature of 330° Fahrenheit, without any decomposition ;
while M. Gay-Lussac, speaking of the crystals in their ordi-
nary state, describes them as being decomposed at so low a
temperature as 236° Fahrenheit. As these statements may
be thought contradictory, while at the same time a correct
knowledge of these facts is required for understanding an in-
teresting point of theory,—the action of the sulphuric on oxalic
acid,—I have re-examined the subject with the hope of cor-
recting any inadvertence which may have been committed.

In the experiments which I have made with this view, the
heat was applied through the medium of a small mercurial
bath, heated by alamp: the acid to be decomposed was con-
tained in a small glass tube, the sealed end of which was
plunged into the bath, and its other extremity connected in
the usual manner with a mercurial trough. The tempera-
ture was ascertained by fixing the bulb of a thermometer in
the bath during the whole continuance of the experiments.
By operating in this way I found that my former statement
was strictly correct. Oxalic acid containing only one equi-
valent of water, whether prepared by merely heating the or-
dinary crystals or by sublimation, sustained a temperature of
330° without yielding either water or gas. As the thermo-
meter rose from $30° to 340°, gas began slowly to appear, and
at 370° it was freely disengaged. It hence follows that the
best temperature for subliming oxalic acid is 330°: it then
sublimes with rapidity, and yet there is no loss by decomposi-
tion; but before exposure to this degree of heat, the acid
should previously be dried as much as possible at a lower
temperature.

But it does not necessarily follow, because my statement is
correct, that that of M. Gay-Lussac should be erroneous. On
the contrary, though we differ as to the precise degree of heat
at which decomposition takes place, I find that crystallized
oxalic acid, containing one equivalent of real acid and three

* Communicated by the Author.
+ Phil. Mag. and Annals, N.S. vol. ix. p. 161.

[t See also Phil. Mag. and Annals, vol. x. p. 153,-—Eprt. }
of

Dr. Turner’s Notice on Oxalic Acid. $49

of water, is decomposed by heat at a lower temperature than
the same acid after two equivalents of water have been re-
moved. Thus, on operating with the fully hydrated acid in
the same manner as with that which had fully effloresced on
the sand-bath, fusion took place at 209°, as stated by M.
Gay-Lussac, and not at 220° as I had found in heating some
crystals, which must previously have lost a little of their water
of crystallization. As the temperature of the bath rose to
230°, the fused mass remained quite tranquil, yielding a little
water, but not a particle of gas. At 240° there was still
scarcely any gas, and very little at 250° or 270°. Even at
290°, though there was violent ebullition from the rapid
escape of aqueous vapour, yet the evolution of gas was by no
means abundant: it became free at 310°, and was rapid at
320°. In a second careful experiment the results were pre-
cisely similar. lt is therefore apparent that oxalic acid, as
deposited in crystals from solution, is decomposed at a consi-
derably lower temperature than when it contains only one
equivalent of water.

My observation on the decomposition of oxalic acid by sul-
phuric acid induces me to dissent from the explanation which
M. Gay-Lussac has suggested. Sublimed oxalic acid, acted
on by a considerable quantity of strong sulphuric acid, began
to effervesce by being kept for a few minutes in a vessel of
boiling water. The action indeed was slow, but it was per-
fectly distinct and continuous, the disengaged gas consisting
as usual of equal measures of carbonic oxide and carbonic
acid. ‘The effervescence was much more free at 220°, and
still more so at 230°; and yet the same acid, exposed to mere
heat, would not have yielded a particle of gas at the tempera-
ture of 330°. Oxalic acid, in its most hydrated state, if mixed
with a large excess of sulphuric acid, is decomposed at nearly
the same temperature as it is after having lost two-thirds of its
water, effervescing with moderate freedom at 220°; whereas
it may be heated by itself to 230° without decomposition.
As the temperature in all these experiments was ascertained
by the same thermometer, they are quite independent of any
error in graduation. Such an error, which must be slight if
it exist at all, cannot account for the comparative results ob-
tained in my own experiments, though it may in part explain
the discordance in the observations of M. Gay-Lussac and
myself. It may surely therefore be inferred, that the decom-
position is not due to the sole agency of heat; and we may,
I apprehend, continue to explain the phanomenon on the
principle which has been hitherto generally admitted.

1 concur with M. Gay-Lussac respecting the composition

of

350 Mr. Daniell on a New Register-Pyrometer,

of the gas evolved from fully hydrated oxalic acid when de-
composed by heat. According to my observation, the ratio of
carbonic oxide to carbonic acid is always nearly as five to six.
A similar mixture is evolved from the acid after two-thirds of
its water has been withdrawn, provided the heat be slowly
applied; but when the decomposition is very rapid, I have
generally obtained a still smaller proportion of carbonic
oxide. On one occasion this gas did not exceed 31 per cent.
The statement of M. Gay-Lussac relative to the appearance
of formic acid, and the explanation which he gives of its pro-
duction, appear to me perfectly correct.

XLIV. On a new Register-Pyrometer, for Measuring the
- Expansions of Solids, and determining the higher Degrees
of Temperature upon the common Thermometric Scale. By

J. Freperic DaniE.1, Esq. F.R.S.

[Concluded from p. 279.]

SHALL now collect together the results of the preceding

experiments, for the purpose of showing what conclusions
may be derived from them with regard to the degrees of tem-
perature which they indicate when referred to the common
thermometric scale. I shall make the calculations first upon
the supposition that equal amounts of expansion denote equal
increments of temperature; and I shall thus be enabled to
compare the present series with that which I formerly obtained
with my first pyrometer, and to offer a few remarks upon the
differences of the two.

I shall adopt the corrected temperature of 662° (350° cen-
tigrade) for the boiling point of mercury, as proposed by
MM. Dulong and Petit; which agrees very closely with the
amount employed in my first calculations, and which, deduct-
ing 62° for the mean temperature at which my experiments
commenced, gives 600° for the interval tor which the several
expansions were determined.

The first column of the following Table refers to the num-
ber of the experiment; the second to the mark of the register
and the bar which was employed; and the third to the amount
of expansion in the same, occasioned by boiling mercury, or
600° of temperature upon Fahrenheit’s scale. The fourth
column exhibits the arc measured upon the scale; and the
fifth the equivalent expansion. ‘The sixth contains the cor-
responding temperature; the seventh records the state of the
metal, which was the object of the experiment; and in the
eighth I have recapitulated the corresponding results of my

former Essay.
TABLE

Jor Measuring the Expansions of Solids, &c. 351

TaBLe X.

ee : F a o,.
2|Mark of|.20°/$5 | .g BPE
S 2 Register | & S/F = | & | Temperature.| Metals observed. EEE
g*Eland Bar| &°|2 £73] & ane
3 5 S\4 am) 5 2h

a Re a |e
= ae P ° 2 - °
7 |Platinum}0152) 5 49 |0508/2005+465|2070|Copper, fusing point.| 2548

II

8 |Platinum|-0159| 6 10 |-0537/2026+65/2091| Gold, fusing point. | 2590
Iil

Tron |'0229} 9 2 |:0787|/2061+65/2126) ditto ditto

12 |Platinum|]‘0116} 4 10 |-0363/1877-+65,1942) Silver, fusing point. | 2233
13 et 0203) 7 24 |-0645/1906+65/1971 ditto ditto
14 Pieaean 0116) 6 16 |'0546|2824+-65|2889) Iron, fusing point. | 3479
17 i 0203] 2 45 |0239).708+-65| 773) Zinc, fusing point. | 648
18 ips 0245) 4 7 |0358) 876465) 941] Zinc, inflaming.

The most remarkable fact displayed by the preceding com-
parison is the beautiful accordance of the results obtained
from two metals whose expansions are so different as those of
platinum and iron. The temperature indicated by the latter
exceeds that by the former in the instance of the fusing point
of gold 35°, and in that of silver only 29°; and this excess is
in accordance with the conclusion of MM. Dulong and Petit,
exhibited in Table II., that the expansion of iron increases
in the higher degrees in a greater proportion than that of
platinum.

The discrepancy between the temperatures derived from
the observations with my first pyrometer and the present are
considerable, but may be sufficiently accounted for by the dif-
ferences in the circumstances of the experiments, without im-
puting inaccuracy to the instrument. In the paper to which
I have before alluded, I stated that “ I did not offer the re-
sults as positive and accurate determinations of the different
degrees, but only as nearer approximations than any that had
yet been furnished from actual observation. The only method
which I had it in my power to adopt for the purpose, I do
not consider to be susceptible of absolute accuracy. he ar-
rangement made consisted of a muffle of black-lead placed in
an excellent draught-furnace. This muffle was furnished with
a door, through a round hole in which the stem of the pyro-
meter was passed up to the shoulder. Another door, which
‘could be stopped at pleasure, admitted a full view of the in-

terior,

$52 Mr. Daniell on a New Register-Pyrometer,

terior. The metal to be tried was placed in a small black-
lead receptacle, of the same thickness as the pyrometer tube,
in the middle of the muffle. Now it is evident that the pyro-
meter so situated would indicate the mean heat of the whole
of the muffle; which heat might, and did, vary in different
parts. Of two pieces of silver of the same size placed within
an inch of each other, one fused some time before the other.”
I also suggested that “* means might be contrived to surround
the instrument with the metal in a state of fusion; but that it
required particular opportunities, which it was to be hoped
that those would avail themselves of who had them in their
ower.”

That the latter method is the only one which can admit of
accuracy will be evident from a few reflections. Setting aside
the inequality of the heat of different parts of the same
heated muffle, which however is a consideration of the utmost
importance, it is obvious that its temperature must consider-
ably exceed the true melting point of the metal exposed to its
influence. Just as a piece of ice would never melt in a cham-
ber of the temperature of 32°, but would require a consider-
ably higher heat in proportion to its mass to supply the ca-
loric which becomes latent during the process,—a mass of iron
would exhibit but little signs of liquidity till subjected to a
heat much above its true point of fusion. When once ina
liquid state, beth would rapidly rise to the temperature of the
medium to which they were exposed. When metals are melted
for the purposes of the arts, they of course require to be heated
very far beyond their fusing points, that they may flow into
the minutest fissures [hollows] of the moulds in which they
are cast, notwithstanding the cooling influences to which they
are suddenly exposed. In some of the finer castings of brass,
the perfection of the work depends upon the intensity to which
the metal is heated, which in some cases is urged even beyond
the melting point of iron. With a fire whose power in all
cases must so greatly exceed the temperature required, it is
necessary to bestow great care in supplying the metal gra-
dually, as we have before described; as it is inconceivable
with what rapidity it rises after the solid pieces are completely
dissolved. Evidence of the same fact may be derived from the
experiments of MM. Clement and Desormes, which I have
before quoted. They calculated the heat of melted iron at
3988°, and of iron just on the point of melting at 3164°,—a
difference of 800°. And it is clear from the circumstances of
the experiment, that the former must have considerably ex-
ceeded the true melting point, or it never could have been
transported in a liquid state from the crucible to the appa-

ratus

for Measuring the Expansions of Solids, &c. 353

ratus in which the water was heated or the ice melted. It is
probable that the process which they employed, of the calori-
meter, was not susceptible of great accuracy; but the discre-
pancy of the results from those which I obtained from the
metal in analogous circumstances is not great.
Iron just melting ........-. 3164° by the former
2889 by pyrometer
—— 275° difference.
Iron melted at a high heat 3988 by the former
3479 by pyrometer
—— 509° difference.

A similar excess also appears in their determination of the
heat of melted copper, and obviously admits of the same ex-
planation.

After performing these experiments upon the melting points
of the metals, I was desirous of ascertaining the effects of the
most intense heat which it was possible to produce in a fur-
nace; and to measure the utmost limits of expansion in a
platinum bar. For this purpose I made use of an excellent
wind-furnace in the Royal Institution, in which upon former
occasions hob-nails had been completely fused into a button.

Exp. 19.—The register I, which had not been the least in-
jured by the previous experiments, was fitted with a new bar
of platinum which had been drawn as a wire, was ;°;ths of an
inch in diameter and very ductile. The iron bar was also
adjusted to a new register, and both were placed upright in a
well luted crucible. About half an inch of powdered charcoal
was strewed upon the bottom to prevent any adhesion; and two
soft iron nails, and a piece of unglazed Wedgwood’s porcelain,
were thrown in for the purpose of affording some indication
of the degree of heat attained. The crucible was then set in
the furnace, another smaller crucible inverted upon it, covered
with coke, and the heat urged to the utmost for two hours.
The fire was suffered to burn out, and the crucible with its
contents removed for examination. It was sound, but the
luting had been completely fused. The nails were found melted
into two complete buttons, and the porcelain was partially
fused upon the surface.

The register I. appeared to be uninjured, but the platinum
ring and wedge were loose, evidently from a contraction hav-
ing taken place in the substance of the black-lead. This was
no doubt owing to the heat having exceeded that at which it
had been originally baked. ‘The amount of expansion conse-
oagneth could not be measured. The platinum ring, both of
this and the other register, exhibited a remarkable change of
texture; they had become very rough and crystalline, and

N.S. Vol. 10. No. 59, Nov. 1831. 22 were

$54: Mr. Daniell on a new Register-Pyrometer,

were perfectly brittle, breaking easily between the fingers.
The platinum bar also, which there was some difficulty in
removing from the cavity, presented a very extraordinary ap-
pearance. It was apparently embossed with crystals, and was
evidently larger at the lower end than at the top: it was also
something contracted in length. Upon examination with a
lens no regular facets could be detected, but it had the appear-
ance of a bar constructed of plates of native platinum loosely
welded together.

The register which contained the iron bar was considerably
bent, and had several transverse clefts in its substance, owing
possibly to its having become inclined in the crucible. Partial
fusion had taken place upon the surface of the bar, which had
run down and formed a knot at its lower extremity. About
an inch of the same end was found to have been converted
into steel, but all the rest retained the character of soft iron.

Exp. 20.—I repeated the last experiment with the same
platinum bar in the register I. The arrangement was pre-
cisely the same, with the exception of the second register with
the iron bar, and the fire was maintained with equal intensity
for an equal time.

The iron nails were found perfectly melted, and the porce-
Jain superficially fused as before. ‘The ring and wedge, how~
ever, were fixed in their places, and the index undisturbed,
but the measure was unfortunately lost from an accident.
The texture of the platinum ring was changed, as in the pre-
vious experiment, and the bar tightly fixed in the cavity. By
frequent gentle concussions it was removed without injury
to the black-lead, which had some slight marks of fusion upon
its surface, but was in a perfectly good condition. The bar
was in a still rougher state than before, highly crystalline, and
exhibited several large longitudinal clefts in its substance. It
was found, by measurement with callipers, to be ,1,th of an
inch larger in diameter at its lower than at its upper end,
and seemed to be approaching a state of complete disintegra-
tion. It was, however, perfectly hard and inflexible. My
intention was to have again exposed it for several hours to
the same degree of heat, with the expectation that the disin-
tegration would have been complete, and that it would actually
have fallen in pieces during the operation: in the mean time
I chanced to make it red hot upon a common charcoal fire ;
and upon attempting to lay hold of it with ‘a pair of tongs the
two ends dropped off, and I only withdrew the small portion
which I had grasped, and which was flattened and fractured
by even this slight compression. ‘The two ends were after-

wards carefully, but with difficulty, raised from the fire, fin
when

for Measuring the Expansions of Solids, &c. 355

when cold were perfectly hard and inflexible. I again heated
a portion of the bar to a dull red, and it crumbled to powder
from a slight blow with a hammer.

Exp. 21. — It being a point of the greatest interest to
ascertain the maximum of expansion which took place in the
platinum previous to this remarkable change of structure, I
adjusted the original platinum bar, with which the greater part
of my experiments had been made, and which presented a
perfectly smooth surface, and was very soft and ductile, in the
register I. A crucible was placed in the same wind-furnace,
containing only a little charcoal powder, with the iron nail
and fragments of porcelain as test pieces. The fire was urged
to the utmost; and when it had been continued two hours
the cover was removed, and the register, previously made
red hot, was carefully introduced, the cover replaced, and the
ignited fuel heaped upon it. At the expiration of a quarter
of an hour it was lifted out.and cautiously cooled. An ex-
cellent measure was obtained, and the arc determined to be
7° 24’ = expansion ‘0645.

The test pieces were found in the same state as in the pre-
vious experiments. The platinum bar was loose in the cavity,
and had not altered its form; but its surface had assumed a
slightly crystalline texture, and it had become very hard and
inflexible.

The expansion registered would, upon the hypothesis be-
fore assumed of equal amounts of expansion denoting equal
increments of temperature, indicate a heat of 3336°; or, add-
ing the initial temperature 65°, =3401°. Butit must be remem-
bered that this is probably rather the temperature at which
the change in the structure of the platinum took place, than
the utmost heat of the furnace. ‘The latter may possibly ex-
ceed the degree at which the expansion of the metal ceases,
and at which its particles evidently form a new arrangement ;
but this point cannot at present be determined. The coinci-
dence of this result with that obtained in the former series of
my experiments, is very remarkable. ‘The temperature at
which I obtained the fusion of cast iron at that time was cal-
culated at 3479°, and was produced by the utmost energy of
an excellent wind-furnace; and this, it will be observed, is
within 80° of the present maximum.

Exp. 22.—Being desirous of ascertaining whether the re-
gister and platinum bar had undergone any change in their
rates of expansion by the intense heat to which they had been
exposed, I again adjusted the latter in the register I, which
had now been once immersed in melted iron, and three times
subjected to the action of the wind-furnace, and boiled thena

2Z2 for

356 Mr. Daniell on a New Register-Pyrometer.

for ten minutes in mercury. ‘The arc measured was 1°19/ =
expansion ‘01148: the difference of 1/ may safely be ascribed
to the uncertainty of the reading.

The temperatures thus determined will require correction,
if we adopt the conclusion derived from the experiments of
MM. Dulong and Petit,—that the dilatability of solids, re-
ferred to an air-thermometer, increases with the heat. The
amount of this correction will be as the rate of increase; and
according to those gentlemen is 11°6 of the centigrade ther-
mometer, or 20°°8 Fahr. from $2° to 572°, or the calculated
temperature is to the true as -00091827 : 00088420. Sup-
posing the increase of dilatability to continue the same for
equal intervals of temperature, which however has not yet
been proved, the following Table will exhibit the corrected
temperatures derived from the preceding experiments with

the platinum bar. .
Taste XI. Observed. Corrected.

Melting point of silver .........ccsecseesvee 1942 ... 1873*
— COPPET ..rocscecccceevssee 2070 ... 1996
= MOMS ads batnecndemdovassun/ S091) sony OLE
| HEOR isan cxessndduceecseess 2E8Q: 040) 2786
Temperature of the maxi- : platinum... $401 ... 3280
mum of expansion of... ;
If we reason in the same way from the increase of the dila-
tation of iron, as laid down by the same authors, the discre-
pancy between the temperature derived from the platinum and
iron is very considerable; the melting point of silver coming
out 1682°, and that of gold 1815° by the latter: but I con-
ceive that the determination of this point in the iron is open
to. objections which do not apply to the platinum, and my
suspicion is confirmed by the anomalous expansion of the iron
exhibited in Tables V. and IX., and to which I shall recur
upon a future occasion. ar
The general utility of the pyrometer, however, will in no
way be affected by any uncertainty in these corrections. The
indications which it is capable of affording will always be
positive determinations, which it will be easy to modify by
calculation, as our theories may improve. For all common
purposes (and I must own that [ look forward with hope that
this instrument will prove eminently useful in many of the
common processes of the arts) it will not even be necessary to
note the expansion indicated by the arc measured; but each
minute of the degree may at once be valued in degrees of

* Mr. Prinsep, from a laborious series of experiments upon the expan-
sion of air confined in a bulb of gold, determines the melting point of silver
to be 1830°,—Phil, Trans. 1828, p. 94. :

Fahrenheit’s

ne —_

Mr. W. S. MacLeay zn reply to Ruralis. 357

Fahrenheit’s scale at the time of taking its rate of expansion
by the boiling of mercury: and a Table of such values should
be furnished for each register by the maker of the instrument.
The following, for example, would be the proper Tab ef or
register I, which has been so often referred to, in which the
arc for the boiling of mercury or 600° (without adding the
initial temperature) was 1° 20!.

TasLe XII.

=) Expansion. Temperature. oy; Expansion. Temperature.
1 0c 008 (27450 0 1ON=") 00145 ash 75
0.30: = :00486 = 225 0) -Su==):0007 201237

0 20 = :00290 = 150 0 §2 = 00029 = 15

0 15 = :00218 = 112 | Oo 1 = :00014 = 7°5

With such a Table an intelligent workman could employ
the instrument without any material error. Those who might
object to the expense of a platinum bar may substitute an iron
one for ordinary purposes, and the cost of the black-lead re-
gister can never be an obstacle to its general use. Other sub-
stances might obviously be employed in its construction, but
the facility with which it can be worked, its small expansion,
its infusibility, and the impunity with which it bears the most
sudden changes of temperature (as when red hot it may even
be quenched in water without injury), will probably always
give the black-lead ware the preference. The only precaution
to be taken with it is to expose it previously, out of the con-
tact of air, to a heat at least as great as that in which it is in-
tended to employ the instrument.

XLV. Correction of a Quotation in a Paper “ On the Impedi-
ments to the Study of Natural History,” published in the
Phil. Mag. and Annals for May, 1831. By W.S. MacLeay,
Esq., M.A. F.L.S. §c.

To Richard Taylor, Esq. &c. &c.
Dear Sir,

Your Correspondent who signs himself ‘ Ruralis,” has
in the Phil. Mag. and Annals for May last given us a me-
lancholy picture of ‘ the Impediments to the Study of Natural
History.” In his list of them, however, I think he has omitted
to make mention of that impediment which I fear has most
thwarted his own progress in the science. But this is of the
slightest consequence ; and indeed were it all, I would not have
troubled you on the present occasion. But I must beg of your
Correspondent that in future, when he does me the honour to
quote from any work of mine, he will cite the exact words,
and not make me the author of downright nonsense. I have
nowhere said that “the discovery of a natural system, being
the

358 Mr. Henwood’s Notice of a Geological Survey

the work ofan all-wise, all-powerful Deity, can only be hoped
for from a cautious process of inductive and analogical rea-
soning.” And yet this stuff is put within commas, as if I had
written it. Allow me to say also, in reply to the editorial note
affixed to this singular quotation, that I have nowhere desig-
nated “* any attempt to unravel” the Plan of the Creation, as
the Natural System.

By the way of conclusion, I may remark that your Corre-
spondent is happily not in any way obliged to trouble his
brains with the “ repulsive and inscrutable” innovations of
“ revolutionary Zoologists.” And therefore advising and hoping ~
that in future he will stick close to ‘* the familiar and popular
Entomology” which amused him ‘in those happy days long
gone by,” I remain, my dear Sir, yours &c.

W.S. MacLeay.
XLVI. Notice of a Geological Survey of the Mines of Corn-
wall; with a Programme of an intended Arrangement of the
leading Details of the Metalliferous Veins, §c. By W. Jory

Henwoon, £.G.8.

To Richard Taylor, Esq. &c. §c.
Dear Sir,

ib the year 1829, at the desire of R. W. Fox, Esq. of Fal-

mouth, and C. Fox, Esq. of this place, who also defrayed
the expenses incidental thereon, I made an examination of the
leading geological features of several of the mines in Corn-
wall; and a short residence in the neighbourhood of Tavi-
stock, in the summer of 1830, afforded me an opportunity
of extending my investigations to some of the mines there.
The results of these inquiries were communicated to the Royal
Geological Society of Cornwall, in October last, and were to
have been honoured with a place in the forth-coming fourth
volume of their Transactions.

But in consequence of the liberal aid and encouragement
of most of the noblemen and gentlemen resident in, and con-
nected with, this county, as well as of several distinguished sci-
entific men elsewhere, I have commenced a survey of all the
mines in Cornwall; and I have now examined all those west
of Redruth. Besides noticing the geological relations of the
veins, (*lodes”, ‘cross courses,” “ flucans,” “ slides,” and
‘elvan courses”,) and of the rocks they traverse, I ascertain
the temperature of every stream I find running or jetting out
of the unbroken rock, and make experiments on the electro-
magnetic properties of the veins*.

After having gone through all the mines, I shall endeavour
to arrange and classify my observations; and the Council of

* Fox, Phil. Trans, 1850, part ii.

the

of the Mines of Cornwall. 359

the Cornwall Geological Society have kindly permitted me to
withdraw the before-mentioned paper, in order to its being
incorporated with the rest. When completed, I intend leaving
my work at the disposal of the noblemen and gentlemen whose
liberal assistance has mainly contributed to its completion.
But before I proceed, I am anxious to submit to your geolo-
gical readers a Programme of the manner in which I had
intended arranging the details, and I shall be exceedingly
obliged to any of them who will trouble themselves to point
out the defects, and to suggest improvements. ‘Those who
are unacquainted with the interior of a mine will doubtless
notice in this outline many points of interest not described ;
the contact of veins at various depths, unseen ; and a general
scantiness of information. I may observe, that the excavations
are not always extended to the points at which interesting
phenomena may be expected; operations may have been
suspended, and the sides of the excavations either fallen to-
gether, been filled with water, or with foul air which ex-
tinguishes candles; the vein may have been entirely worked
away, and in most cases the sides are after a short period
inyested with a crust of ferruginous matter, which rapidly
accumulates. In a few instances I have not deemed it pru-
dent to expose myself to falling rubbish, on decayed wood, or
on rotten ladders. None but those who have experienced the
like can fully feel the many vexatious disappointments I have
had to suffer, in meeting an immovable barrier sometimes but
a few fathoms, or even a few feet, from my object; after having
crept hundreds of fathoms on all-four, and often on the belly,
through mud and water, often beneath tottering rocks. ‘These
inconveniences, to which geologists who confine themselves to
the neighbourhood of the surface are not exposed, have been
every-day occurrences with me; and I venture to hope that
they may with some propriety be offered as an apology for the
deficiencies which my outline will at every step present.
I remain, &c.

Perran Wharf, near Truro, Ww. J. Heywoop.
August 11, 183].

PROGRAMME.
Cookskitchen Mine, parish of Illogan, near Redruth, is
situated on the northern side of the granitic range, of which
the nearest hill (Carnarthen Cairn) is only about half a mile
distant, and its acclivity is at an angle of about 7°. The
phznomena of the interlying of granite and slate which here
occur have been often referred to, having for a considerable
time been supposed to be peculiar to this mine. ‘The eastern
part of its surface is nearly horizontal; but towards the west
it rapidly declines.

Lode. Direction in Dip in

Depth and Composition or Contents, |
Slate. | Granite.} Slate. | Granite. i

Small western? |........ 8°W.of NJ ....... 119f™*. Veins of radiated quartz, with
Cross course i friable granite intenposeds ic)... +...
(Cross Veltils sem cee rs tk HUBUE-IN.| sreratetereats 119 £™’. Two veins of radiated quartz, with}
Titde “aks a vein of friable granite between them .
= a2 ross t 35° E lof N. 50: | 33 f™° (In slate.) Angular masses of slate}

with a vein of radiated quartz on E, dg

|
87£™*. Friable granite mixed with radiated]
quartz; a vein of granitic clay on W. sid
...|Surface to 10 fathoms ........ “to
10 fathoms to 40..... denatehetliatarels © aie oe |

South lode ....

40 fathoms to 49....... SSE GN nis si Pei

49: Tathomsn jas: s.sevalate aoe pleiyin ein |=\<(ofaic’aiata
54f™*, Brown iron ochre, slate, quartz,
iron, and yellow copper pyrites, “ walls"

smooth! i 7G ese ile Mitotic o> Stee a
95 £™°. Quartz and slate with a little cop+}
per pyrites's cic. Uhvcausbeew. «sa =) eee
Los ditto (‘¢ walls” smooth)!

|
aI
|
|

2° N.jof W.

119f™*, W. of Cross vein, yellow sulphuret

of cOpper .c..sihc5... 6. ee |

E. of ditto gray sulphuret

OF COPPET: soc cyesicre = 'ae) nt aa

E. of West Cross course, yellow}

sulphuret of copper with chlo-}

rite and friable granite... ... |

5° S.lof W. Onan Me oer, 54£™°, Brown iron ore, quartz, and yellow}

copper pyrites. 20.2.0) 0... clan
72£™*. Friable granite and iron pyrites .
103 f™,. Red iron ore and crystalline

quartz, a vein of granitic clay on N. side |

: 112f™*. Red iron ore and quartz...... | ,

of W. GSe. He 33f™*. Gray sulphuret of copper, brown] —

||

Toy’s lode.....

Great lode.... 10° S.
iron ochre, slate and quartz; a vein o
slaty. Clay. Ge.c/% aeetatensrataie, re 73 can

67 fathoms* =f! 2.0. 4.10 <s oeteein, 9 eee ‘d

112 f°, Gray and black sulphurets, and]
red oxide of copper, red iron ore, and}
iron pyrites. At the contact of Toy’s}

lode, a vein of granitic clay .....+--+ 1 |

Dunstan’s lode*)....... OSLO Wal > tee 105 f™*. Friable granite ..........--. |
Middle Engine 18° N.lof W. ..|93£™*, Quartz, chlorite, and yellow cop |
lode? 2 Seat } per pyrites, two veins...........-+.+4]
BT es oe cw ce. oo 5 epee te neat eae

87f™*, Friable granite and gray sulphuret
of copper } ja, / jodi gneyiniaueet eerie |

Hardshaft lode*| 18° S.jof W. | N. 58° |........ 31£™*, Slate, crystalline quartz and ye |
low copper pyrites ........-++-+405 \
54 £™*, Slate, a vein of slaty clay on N. side |
Sawpit lode ...|2°N.ofW.)....... perpendijcular . {54 f™*. Slate, red iron ore, and felspar ¢' ‘|
Lode N. of 2 |4°N.of W.|.... ecoalt Nev OD ltt aararereet 54f£™, Slate, brown iron ochre and iron
Sawpit lode§ pyrites Se eivs a UAH cietewe = «ole ° oa bi }

2 4

* The out-crop of these “ lodes”’ (if there be any) is not seen.

South Lode. Great Lode.

Direction of Direction of

Dip of Strati-

eg fication or Appearance of Granite, and Eeaeeiand ce Heave, and | 2 .
Sw | Cleavage of | its Dipat Junction, &c.&c.) if to the | 23 | if to the | [%
a. Slate greater or | #5] greater or | Gy
m0 = smaller | = smaller | 55
Angle. Angle. <

Beietesn(e DOOT OE RIE Shs Ano SO ORONO Panton coe Oy iN TA Ag
Bratetewrats Sere o foe meietemtehteitcalscles celal Retg tt, Gialeaoe

Deep blue, dip} At this spot there is also gra-| _
N.W. 34° nite, which is traversed by
many veins ofa fine-grained
dark gray schorl rock .
Saint latol aiae .. |Near the cross course soft,
and mica more abundant
than at alittle distance... .
ain ie ee .. |Coarse- grained, soft, and
.|Deep blue, dip| tinged red: dip of junction
N. 50°. 65°} S. 22°,
-eeeeee+....|Fine-grained with imbedded
crystals of schorl.
N. side slate, |S. side of vein granite,

Pap a (ae Rskf™ SA| 39°

of crystals of felspar & mica

7
Sw
5°

_

a)

n &

35

88

wn

z3

ae

23

dip N.W.34° 2 §
dip S. 12° S58

2 ft. o 2
=e

: ~

AVE ( clnlo'ain'~ <Wvia, ats The slate and granite gra- aes

4 ft. dually pass off from one/§ 22 4 3g

into the other, there being/S = ~ a
no distinct separation. ares aa ="

SRREIEMINAS (aie » nic’ slei~ che Traversed by numerous veins|“ 7 = 2 ® 5]

of the fine-grained schorl 3 SS 2 . aos

Sh ft. rock, (52 Es Sey

Sash Lag |Es

Oe Cou & @ je | or

oe an oT HY 1

Spee) atic o en =e Qo

5 ft. BSfe8 Se 2 oOlss
[2328 Gok? IBS

S%758%5 Sa2% 0/25

AR Mian sists stokes 2 iT ee Go 8 7s poe
. eeeees foe emer ewes cess ene o- . Ga Oo =o = =

- pessa Bsc2 s/25
4 in. |} Bs OS El E09
Ua Lion een!

= eweoife

4 ft uc) noc bees <)

SU stale Aacinie:pre PAG Boe hot Awe S4anecdot BESO si5| °8

4 ft aom gel ig

. oTwy,RE hay
ae § elas]
Bee Sales
SOO 8 Sloe
3 ft. See, One
=
Petite tin'vie sisi «'-| Dip Ni 62°, SS&ocerl ss
SSR tle w
eae Sssf e258
9s $2) - i [—%
a aan we.

ro) ond al a
5 ft. || 2-30.,- | |Spots of granite in the slate 4
1 ft. || 224A ¢| here, a
Be sg ms
’ < ZAG to @
8 in. iA ira,
seeeelseeeeeeees. {Structure not uniform: nests 28
ait

e

al

“

ao)

4 ft. 3
4

Qk ft. 4
4 ft. |Deep blue, N.|S. side, much mixed with | @
side ..... | slaty particles. tHe

20 in. |Traversed by 5 B,
veins of fel- 78

3 ft. | spar clay. >
g

N.S. Vol. 10. No. 59. Nov. 1831. SA In

362 Mr. Henwood’s Survey of the Mines of Cornwall.

In the preceding columns the “ direction” is with regard
to true north, and the dip in deviation from the horizon.
When in its horizontal course one vein or lode is intersected
by another, and the parts on opposite sides of the traversing
vein are not exactly opposite to one another, the intersected
“lode” is said to be * heaved.” Whether we approach the
traversing vein from the east or west, on the course of that
which it has “ heaved,” still in either case the dislocated por-
tion on the opposite side will be found by turning to the same
hand; and thus a heave to the “right” or to the “left” is the
same on either side:—this is the meaning of the letter R in
the foregoing Table. The GA and SA refer to whether the
dislocated portion is to be found on the side of the “ greater ”
or “smaller angle.” The prevailing dip of the “bunches”
of ore in Cookskitchen is to the westward; but I forbear en-
tering on that branch of the subject, or on a discussion of the
laws which may perhaps be ultimately found to regulate the
distribution of metalliferous minerals, as such inquiries would
be foreign to the object of this communication.

Cookskitchen Mine, Parish of Illogan, Cornwall: transverse
Section.

[Scale 32 fathoms to an inch.]

Allusions to the accompanying figure. The shaded portions
denote granite; the unshaded, slate. a@ South lode; 6 Toy’s

=e
pele ah See
é :

Henwood del.

lode; c Great lode; d Dunstan’s lode; e Middle Engine lode;
J Uardshaft

On the Disinfecting Powers of increased Temperatures. 363

J Hardshaft lode; g Sawpit lode; 4 Lode north of Sawpit
lode. It seems probable that Hardshaft, Middle Engine, and
Dunstan’s lodes are only “ branches” of the Great lode. ‘The
dotted lines respectively denote the suspected continuation of
the various *lodes” and of the masses of granite ;—these points
are said to have been seen by others. The full lines denote
what J have seen, the dotted portions what I have not seen.

XLVII. Experiments on the Disinfecting Powers of increased
Temperatures, with a view to the Suggestion of a Substitute

Sor Quarantine. By Witttam Henry, M.D. ERS. &c.

To the Editors of the Philosophical Magazine and Annais.

Gentlemen, Manchester, Oct. 14, 1831.
GEVERAL years have elapsed since I was requested, by

an eminent merchant of this town* extensively concerned
in the importation of Egyptian cotton, to take into conside-
ration, whether any effectual method could be devised of
guarding against the introduction of the Plague into this
country by means of that raw material, without incurring the
serious commercial sacrifices, which then attended the enforce-
ment of the quarantine laws on large cargoes of that article.
Chlorine might have been proposed for the purpose; but it
was evidently inapplicable, not only on account of its chemical
activity on vegetable substances, but of the necessity of washing
and drying the cotton, in order to free it from any adhering
portions of that powerful agent, the smallest remains of which
would be injurious to the spinning machinery. In proposing
any new method of destroying contagious matter, it was repre-
sented to me as quite essential that it should be incapable of
impairing, by its chemical action, the tenacity of the fibre, as
this would unfit the raw material for the operations through
which it has subsequently to pass.

By this restriction, the ground for experiment was consider-
ably narrowed ; and after giving much attention to the subject,
no means occurred to me of effecting the object in view, but
that of applying to the raw cotton such a degree of heat as,
while it should do no injury to the staple of the article, might
yet be sufficient for the destruction of any contagious virus
which it might have imbibed.

That the contagion of the plague, supposing it to be present
in the state of fomites+, might be rendered innoxious by a

temperature

* William Garnett, Esq,

+ Fomites (the plural of fomes, fuel) expresses contagious or infectious

$A2 matter

364 Dr. W. Henry On the Disinfecting Powers of increased

temperature below that of boiling water, appeared to me not
improbable, trom the evidence of a fact recorded by various
writers; viz. that the plague, in countries where it prevails,
ceases as soon as the weather becomes very hot. ‘ Extreme
heat,” says Dr. Russell in his Natural History of Aleppo,
(vol. ii. p. 339.) “seems to check the progress of the distemper ;
for though the contagion and the mortality increased during
the first heats in the beginning of the summer, a few days con-
tinuance of the hot weather diminished the number of new in-
fections. July is a hotter month than June; and the season,
wherein the plague always ceases at Aleppo, is that in which
the heats are most excessive.” In another part (p. 284.) of the
same volume, Dr. Russell states the greatest heat at Aleppo
in June to have been 96° of Fahrenheit, and that of July 101°,
in the shade.

Arguments, also, derived from chemical reasoning, appeared
to me to strengthen the probability that a temperature, raised
to no great extent, would suffice for the decomposition of in-
fectious or contagious matter*. Of the nature of contagion we
are, it is true, entirely ignorant. But we are entitled to conclude
that it is in no case identical with any one of the simple or
compound gases, with which chemistry has made us acquainted,
and which are unchanged by a temperature below 212°; be-
cause each of those gases has been breathed, many of them
very frequently, without exciting a specific disease. The sub-
tile poisons which propagate contagious distempers, being the
products of organic life and of morbid conditions of the animal
body, are, it is probable, of a complex nature, and owe their
existence to affinities which are nicely balanced and easily
disturbed ; even more easily than those maintaining some of
the products of vegetable life, which lose their original pro-
perties, and acquire new ones, when exposed to temperatures
of no great amount. ‘Thus starch is converted by a moderate
heat into a substance somewhat resembling gum; and, by
weak chemical agents, into sugar. Among inorganic com-
pounds, we have a remarkable instance of the effects of heat
(raised however to a higher degree) in the change of phosphoric
into pyro-phosphoric acid. In most cases of this kind, it is pro-

matter existing in absorbent substances, such as wool, clothing, &c.: In
this state of confinement it seems to acquire increased virulence and
activity.

* I use the term ‘ infection’ and ‘ contagion’ as synonymous, because no
sufficient distinction has been established between them. It would be un-
seasonable to enter, in this place, into a disquisition about words ; but those
who take an interest in the verbal part of the subject, will find an excel-
lent view of it (pointed out te me by my son Dr. Charles Henry) in the
Dictionnaire de Médecine, art. Contagion, vol, v. p. 549, Paris 18 22.

bable

Temperatures, as suggesting a Substitute for Quarantine. 365

bable that increased heat produces no change either in the
number or proportions of the atoms of the substances; but
that, in some way which chemical science has not yet pre-
pared us to explain, it modifies only the arrangement of the
atoms, and thus confers new distinctive characters.

In pursuing the inquiry experimentally, two circumstances
seemed to me to require to be established.

Ist, That raw cotton, and other substances likely to har-
bour contagion, would sustain no injury by the temperature
conceived to be necessary for their disinfection.

2ndly, That in at least some one unequivocal instance, con-
tagious or infectious matter should be proved, by actual expe-
riment, to be destructible at that temperature.

I. To ascertain the first point, I submitted in August 1824, a
quantity of raw cotton to a dry temperature of 190° Fahrenheit,
which was steadily kept up in the inner compartment of a
double vessel heated by steam, during two hours. When the
staple of the cotton was examined by Mr. Garnett, he pro-
nounced it to be so essentially injured, as to set at rest, ona
first view, all intentions of adopting this method of purifica-
tion. The same unpromising appearance was presented also
by cotton yarn, which, after being spun, had been heated
during two hours at 190° Fahrenheit. After being allowed to
cool during a quarter of an hour, it was compared with yarn
of the same fineness which had not been heated, with the fol-
lowing result :

Ibs, avoird.
A hank of mule twist (40 to the pound) not heated, ,
2464
required a weight, to break it, Of ....:..sssessseees
: ; : pings
A hank of ditto ditto heated to 190° and 1663

PO REMON CR each inde sabldacbinets aticsbion BE otide pnddbwouas se
The strength of the yarn, measured by its power of sup-
porting weights, had therefore suffered a diminution, by being
heated, of fully one-third. ‘The remainder of the yarn so heated
having been laid aside in a cellar, was accidentally examined
on the fourth day, and had undergone an obvious alteration,
which led to a renewed trial of its strength. It was now found
that a hank of the same yarn supported a weight of 2414
pounds, and it had therefore recovered very nearly its original
tenacity.

At this period I was obliged, by unavoidable circum-
stances, to abandon the inquiry; and the inducement to re-
sume it ceased in a great measure to exist, in consequence
of the discontinuance, for a season, of the pressing inconve-
pience which had given birth to it. It was only recently that
my attention was recalled to the subject by the well grounded

alarm

366 Dr. W. Henry On the Disinfecting Powers of increased

alarm which has overspread the continent of Europe, and in
a less degree extended over this country, in consequence of
the devastating effects of a disease (cholera), the contagious
nature of which is rendered highly probable, and which, like
other contagious diseases, may be presumed to be capable of
being conveyed by fomites. It is therefore of the greatest im-
portance to devise effectual and easily practicable means of
extinguishing the first sparks of that distemper which may
show themselves in this country, avoiding at the same time
greater injury than is necessary to individual interests or to
general commercial prosperity.

The first step which appeared to me desirable, on resum-
ing the investigation, was to decide, beyond all doubt, whether
raw materials, as well as manufactured goods and articles of
clothing, could be exposed without injury to a dry heat
approaching 212°. Of raw materials, I took cotton as the
one which, from local advantages, I could best submit to the
necessary trials; and I had the benefit of the zealous assistance
of a friend* engaged in the spinning branch of that manufac-
ture. Raw cotton of ordinary dryness, as recently taken
from the bag, was exposed, during two or three hours, to a
steady temperature of 180° Fahrenheit, in a vessel heated by
steam of common density. It lost, generally, between two and
three ounces from the pound. The effect on the staple, as
determined by the inspection of persons versed in the article,
was apparently such a degree of injury, as to forbid all expec-
tation that the cotton could be rendered useful. It was pro-
nounced to be rotten, and what is technically called ‘fuzzy,’
and to be unfit even for those operations which are preparatory
to its being spun into yarn. After being left, however, during
two or three days, in a room without fire, a great change had
taken place in its appearance, and it was found on trial to be
as capable of being spun into perfect yarn, as cotton employed
in the ordinary manner. On an accurate trial of the twist
which had been spun from it, a hank supported fully an equal
weight, with a hank of the same fineness spun from cotton
fresh from the bag. This fact, established by repeated expe-
riments, proves that with the recovery of its hygrometrical
moisture, cotton, which has been heated, regains its tenacity,
and becomes as fit as ever for being applied to manufacturing
purposes.

Articles of cotton, silk, and wool, after being manufactured,
both separately and in a mixed state, into piece goods,
for clothing, were next submitted to the same treatment.

* Peter Ewart, jun. Esq.
Among

Temperatures, as supgesting a Substitute for Quarantine. 367

Among them were several fabrics, which were purposely chosen,
of the most fugitive colours and delicate textures. After
being exposed three hours to a temperature of 180°, and then
left a few hours in a room without fire, they were pronounced,
by an excellent judge of the articles who furnished the speci-
mens, to be perfectly uninjured in every respect. Furs and
feathers, similarly heated, underwent no change; and there
can be no doubt that if the apparatus had enabled me conve-
niently to have raised steam of increased density, a tempera-
ture above 212° Fahrenheit would have done no injury to the
delicate and costly articles submitted to it.

II. The most important point to be ascertained, and that
on which the utility of the inquiry hinges, is whether a tem-
perature below 212° Fahrenheit is capable of destroying the
contagion of fomites. The investigation is one of great
nicety, and involves considerable difficulties. It was en-
tirely out of my power to try the agency of heat on those
contagions which propagate the formidable diseases of cho-
lera, plague, scarlatina, typhus, &c. The only way, in which
I could arrive at an analogical inference respecting the de-
composing power of heat over such contagions, was by deter-
mining its effect on some kind of infectious matter which as-
sumes a tangible form, and can in that form be submitted to
experiments; and which admits also of being afterwards tested
by justifiable trials on healthy persons. Nothing presented
itself to me, on consideration, so well adapted to fulfil all these
conditions, as the matter of cow-pock. On mentioning my
views to Mr. Roberton, one of the surgeons of the Manchester
Lying-in Hospital, he obligingly suppplied me with vaccine
lymph, taken from pustules of unequivocal character; and
after the lymph had been subjected to high temperatures, he
directed the insertion of it to be made, in the usual way,
into the arms of healthy children. The trials were conduct-
ed, and the results registered, by Mr. Gee, the House-Apo-
thecary of the Hospital.

1. Vaccine lymph, dried at the temperature of the atmo-
sphere on small bits of window-glass, was exposed to a heat of
180° Fahrenheit during four hours. ‘Three healthy children
of proper age were inoculated with this matter without any
effect ; but being afterwards vaccinated with fresh matter, they
all took the disease.

2. Lymph heated, during the same period, at a tempera-
ture varying from 120° to 140°, generally 130°, was inserted
without effect into the arms of two healthy children, who were
afterwards successfully vaccinated with recent matter.

3. Four pieces of window-glass, on which recent vaccine

lymph

368 Dr. W. Henry On the Disinfecting Powers of increased

lymph was placed, were heated during intervals varying from
two to three hours, at a temperature never below 160° nor
above 165° Fahrenheit. The trials were judiciously varied
by Mr. Gee, by inserting each specimen of the matter which
had been dried, into one arm only of a healthy child; while
into the other arm of the same child recent matter was in-
serted. In every instance, the heated matter proved inefli-
cient; while the matter which had been dried at the tempera-
ture of the atmosphere produced a satisfactory pustule.

4. For the sake of obtaining a sufficient number of in-
stances, I requested Mr. Marsden, House-Surgeon of the
Manchester Royal Infirmary, to make trial of some genuine
vaccine lymph which I had received from him, and had then
submitted to heat. One specimen had been placed two hours in
a steady temperature of 150°; a second four hours in the same
temperature; a third two hours, and the fourth four hours,
in the temperature of 172°. Inno one instance, did any of
these specimens, when inserted in the usual manner, produce
the vaccine pustule.

5. Descending in the scale of temperature, another portion
of vaccine lymph was exposed to an uniform heat of only
120° Fahrenheit for three hours. Two children, inoculated
by Mr. Gee with this matter, received the infection, and the
pustules were, in each case, remarkably well characterized.
From their arms matter was taken, with which upwards of
forty children have been vaccinated, who have gone through
the disease in the most satisfactory manner.

It may be considered, then, as established by the experiments
which have been related,—1st, That vaccine matter is not de-
stroyed by a temperature of 120° Fahrenheit; and it is even
probable that it would sustain, without losing its efficiency,
a heat several degrees higher ;—2ndly, That vaccine lymph is
rendered totally inert by exposure to a temperature of 140°
Fahrenheit. May we not hence infer, that those subtile
animal poisons which lie dormant in the state of fomites,
are likely to be disarmed of their terrors by the same simple
means? ‘The expectation, I am aware, rests entirely on ana-
logy; but the analogy appears to me sufficiently strong to
render it desirable that it should become the parent of expe-
riments. It is with that view only that I propose it to the
enlightened physicians of this and other countries, who have
the means of verifying or disproving the inference by experi-
ments on the more diffusible and active contagions. Until,
indeed, the soundness of the analogy has been established by
a sufficient number of facts of the latter class, no extensive
practical measures can safely be grounded upon it. «

Temperainre as a Substitute for Quarantine. 369

If a favourable result should however issue from these sug-
gestions, nothing can be more easy or less expensive in construc-
tion, or more manageable in use, than an apparatus for subject-
ing articles imported from unclean places, in any quantity, how-
ever large, to the disinfecting agency of a dry heat, without even
the slightest injury to the quality of those substances. A dou-
ble vessel, made of copper, or of tinned or cast iron, of any
convenient shape, with a sufficient space between the two ves-
sels for containing steam, and an interior cavity of due size
for a receptacle of the articles to be disinfected, is the essen-
tial part of the arrangement. To avoid all risk of the escape
of any portion of the virus in an undecomposed, and there-
fore active, state, a pipe, open at each extremity, may be car-
ried from the receptacle into the flue of the chimney, or, better
still, into the fire-place under the boiler, which will ensure
the destruction of the contagious effluvia. The articles should
be introduced into the receptacle, not closely packed, but so
opened out, that every part of them may be exposed to the
necessary temperature. Ifinjury should be apprehended from
over-drying any substance, a small quantity of steam may be
suffered to pass through a pipe from the boiler into the re-
ceptacle. At every sea-port to which ships are bound with
unclean bills of health, an apparatus of this kind should be
provided, on a scale sufficient for the emergency. And on
the Continent, similar provision should be made, at every bar-
rier which is destined to prevent the introduction of conta-
gious diseases.

It must be obvious that these precautions offer no secu-
rity against the danger of a contagious disease breaking out
in a person who has already been exposed to infection, but
in whom symptoms of the disease have not yet manifested
themselves. Risks from this source constitute, however, a
very small proportion, compared with those arising from
fomites; and they may be easily and effectually guarded
against, by insulating the person supposed to be infected,
for a period of time exceeding that, during which the seeds
of the disease have been ascertained to lie dormant in the
animal system. Nor is this proposal meant to supersede the
employment of chemical disinfectants, especially of prepara-
tions of chlorine, in the apartments of the sick; or their
application to articles and fabrics which sustain no injury
by exposure to those agents.

I am, Gentlemen, your obedient servant,

Wiiiam Henry.
N.S. Vol. 10. No. 59. Nov. 1831. 3B XLVII. No-

fi870.>)

XLVIII. Notices respecting New Books.

Montagu’s Ornithological Dictionary ; new edition, “ witha Plan of
Study, and many new Articles and original Observations. By James
Rennie, 4.M., 4.L.S., Professor of Natural History, King’s Col-
lege, London; Author of © Insect Architecture,’ ‘ Insect Transfor-
mations,’ * Architecture of Birds, &c. London, 1831. Octavo;
Introduction, &c. pp. Ix., Dictionary and Index, pp. 592; 28 En-
gravings on Wood.

ti On my plan, any person, with a little care, may become a tolerably good
naturalist, the first walk he takes in the fields, without much knowledge of
books.” —Mr. Rennie’s Introduction, p. iv.

TH Editor of this new edition of Montagu’s Ornitho logical Dictio-

nary, and author of the introductory matter now prefixed to that
work, has recently been appointed to the chair of Natural History in
the King’s College of London, (that is, we suppose, to the chair of
Zoology, since Mr. Burnett is Professor of Botany.) Having been
known to science previously only by the compilations (interspersed
with some observations of his own), of which he is stated to be the
author in the title-page quoted above, and which form part of the
Library of Entertaining Knowledge, he has undertaken the publica-
tion now before us, we presume, for the purpose of evincing his fitness
for the duties, as Professor of Zoology in one of our new national es-
tablishments for scientific education, which have been committed to
his charge. He has also still more recently announced, in pursuance,
we presume, of the same purpose, his intention of publishing “A
Conspectus of Butterflies and Moths,” and a translation “with co-
pious notes and synonymes” of Le Vaillant’s “ Birds of Africa,”
** Birds of Paradise,” and * Parrots.”

We proceed, therefore, to examine the claims to regard as a man
of science and as a public teacher of zoology, which Mr. Rennie has
asserted in the volume now under our consideration.

The introductory matter is arranged under the following heads :
“ Introduction,”—* Plan of Study,”—“ The Use of System,”—“ Sy-
stem of Linnzus and Latham,” The Quinary System and Modern
Doctrine of Types, Affinities, and Analogies,—and “ Catalogue of
Naturalists,” subdivided into “‘ Rudimental Naturalists, ”—‘‘ Literary
Naturalists,"—and “ Philosophic Naturalists, and Original Obser-
vers.”

On perusing this introductory mattter from p. ili. to. p. lx., we were
struck with the extreme assumption and arrogance of the whole style
of treating his subject, which is here displayed by the author; with the
bitterness and contempt of his vituperation of the naturalists whose
views he condemns, disingenuously mingled with praise, which on his
own showing must be undeserved ; and with the perverse ignorance
from which alone such misrepresentations as he makes on all the sub-
jects which he touches, could have arisen. We affirm, in limine, that
his statements respecting the Quinary System and every subject con-

nected with it, are a tissue of errors, from beginning to end. bias
oes

Notices respecting New Books. 371

does not understand any of the subjects he has undertaken to discuss;
he cites his own blunders as characters and attributes of the systems
he impugns, and then actually takes credit to himself for overthrowing
them. There is no such thing in the entire introduction as a fair state-
ment or an examination of any of the systems he proposes to consider ;
all is arrogant, unsupported assertion, mingled with garbled extracts.
His criticism of the various systems of ornithology or of zoology in
general, is exceedingly confused and intricate, and difficultly intelligi-
ble ; and many of his observations are utterly inapplicable, referring
only, in reality, to his own misconceptions of the systems impugned.

Conscious, apparently, of the charges that would be preferred
against him, on account of the misrepresentations which we have now
briefly characterized, Mr. Rennie, in p. v, of his “Introduction,”
offers the following apologetical remark : :

“The offer to print any reply to my arguments, which might b
sent me, exculpates me, I conceive, from all charges of a personal
nature; and it would grieve me much, if my dislike to their doctrines
and language [those of Mr. W. S. Macleay and his disciples] has, in
any instance, betrayed me to infringe upon the courtesy and decorum
which ought uniformly to characterize such discussions. To enter
into any compromise with error, would be unpardonable weakness
and delinquency; but to endeavour, by contempt or abuse, to hurt
the feelings of the person judged to be in error, would exhibit the
character of a bully or a ruffian.”

But we will tell Mr. Rennie, that the offer to print any reply to his
arguments that might be sent him, affords no excuse whatever for
making false representations, (and many such has he made,) which
must necessarily have an effect upon the public mind unfavourable to
the subjects of them, before the replies can appear. As well might
the defamer of the character of any private individual hold himself ex-
culpated from the charge of slander, by his offer to print a denial of his
unjust representations, after they had gone forth to the world, to the
injury of the object of his attack. It is difficult to conceive, also, that
Mr. Rennie’s professions of sorrow, if he should be found to have been
betrayed into an infringement of the courtesy and decorum which
ought to characterize scientific discussions, can be sincere, when we
observe, in almost every page of his portion of this volume, the most
palpable violations of courtesy, of decorum, and of truth. What his
intentions may have been it is impossible for us absolutely to know,
but it is certain that the pages before us present many examples of
contempt and abuse, which in their own intrinsic quality, would be-
come only those characters to which Mr. Rennie, in the concluding
sentence of the above extract, has rightly ascribed the exhibition of
them.

We now proceed to prefer against Mr. Rennie, seriatim, the charges
which, as it appears to us, he has justly incurred by the representations
made in the introductory matter to his edition of Montagu’s Ornitho-
logical Dictionary now before us. We pledge ourselves to prove these
charges, by the most ample and satisfactory evidence, as we proceed in
this review. We shall intersperse them now with various facts re-

3B2 specting

372 Notices respecting New Books.

specting Mr. Rennie’s character as a naturalist, which the perusal of
the introductory matter discloses. His incapacity for the office he has
assumed of Editor of Montagu’s work, will be made abundantly evi-
dent hereafter.

Mr. Rennie appears to be wholly ignorant of the higher philosophy
of Natural History, considered either as a branch of science, as a
means of training the mind to the love of truth, or as an instrument
of leading it to the admiration and adoration of the Creator. He
seems to have little knowledge or perception of the vastness of na-
ture, and none whatever of the fact, that there are such things as de-
sign and order in the distribution of the beings and substances which
compose it.

He arrogantly misrepresents the scientific character of Linneus,
most disingenuously adopting the remarks upon it made by Mr.
W. S. Macleay and some of the naturalists of the School he has founded,
which have been suggested to them by their peculiar views; views
upon which he afterwards heaps abuse, and still more deeply misre-
presents.

His opinions of the merits of the various investigators of nature
whom he has occasion to mention, of the highest rank in their re-
spective departments of science, are pronounced in the most con-
ceited and unbecoming manner : the most eminent and learned na-
turalists, whether practical observers or systematists, are equally the
objects of his contempt: thus we have “the dry, lifeless, marrowless,
and unphilosophic descriptions of the Linnzan school” (p. xxv.) ;
their “ gross inaccuracy” (p. xxx.) ; the ‘‘ Linnean barrenness of idea
and of deduction” (ib.); the ‘hot and testy” behaviour of Linnzus
(p. xxxvii.); the “ briefness and poverty” of Pennant (p. xxvi.); the
“credulous absurdity” (ib.) and the ‘wild, mischievous, and most
absurd analogies” (p. xlviii.) of Cuvier ; and the “trash” of Mohs and
Haidinger (p. xxvii.)*.

Mr. Rennie further betrays the most palpable want of knowledge
of the ordinary meaning conveyed by common forms of expression.
He mingles some portions of the nomenclature of the Quinary System,
in an insidious manner, with the monstrous errors and absurdities

* Inthe Englishman’s Magazine for August last is an article entitled
‘‘ Mismanagement of the Library of the British Museum,” which we have
been informed is from the pen of Mr. Rennie. Its style in every respect
corroborates this information, exactly resembling that of the prefatory matter
to Mentagu. We mention it here, because Mr, W. S. Macleay’s Annulosa
Javanica is characterized in it (p. 589) as a “flimsy production,” the “ effron-
tery” of its “‘ presumptuous author” being mentioned ; while Dr. Horsfield’s
Lepidopterous Insects is stated to be a “‘ worthy companion” to the Annulosa
Javanica, being, therefore, also “a flimsy production” manifesting the ‘“ef-
frontery”of its ‘‘ presumptuous author.”—The flimsy productions, effrontery,
and presumption of Mr.W.S. Macleay and of Dr. Horsfield! authors of some
of the most splendid discoveries and profound researches in zoology which
have ever been accomplished, and whose reputation is spread throughout the
civilized world! To what part of the duties of Professor of Natural History
in the King’s College of London does this treatment of two of the most
eminent cultivators of that science belong ?
which

_

Notices respecting New Books. 373

which he has ignorantly confounded with that system, so as to induce
the reader who is previously unacquainted with the subject, to con-
clude that Mr. Rennie’s representations must needs be founded in
truth, when he would have had nothing but Mr. Rennie’s assertions
to support that conclusion, had an ingenuous plan been pursued.

In the most false and unfounded manner he confounds the athe-
istical doctrine of appetencies, broached by Darwin, Lamarck, and
Robinet, with the Macleayan doctrine of the progression in affinity
from one group of animals to another, or the variation of form of
each species from that possessed by the preceding one, so that on
examining the entire group, a progressive change of character is ob-
servable, made up of the separate differences between each pair of
contiguous species. He asserts, with equal violation of the truth,
that the Quinary System, “while it professes to reject this strange
doctrine, at the same time adopts its very language in the most un-
equivocal manner.” (p. xxxiii.) The truth being, that the doctrines
respecting natural distribution, held and advocated by Mr. Macleay,
or more properly speaking the phenomena which he has discovered
in the progression of affinities, &c. in natural history, afford the most
triumphant refutation of the doctrine of appetencies; and that the
entire scope of some of Mr. Macleay’s arguments is directed against
the very errors in zoology upon which that doctrine is founded.

To support these misrepresentations, Mr. Rennie affirms, with equal
falsity, that Mr. Macleay has borrowed some of his general expres-
sions from Robinet, and, as he would insinuate, with the intention of
imparting the same ideas as that writer. (p.xxxv.) He further expressly
asserts, with the same want of truth, that Mr. Macleay’s “ doctrine
of types” is “directly borrowed from the atheistic system of Robinet.”
(p.xxxviii.) The Rev. W. Kirby, one of the authors of the celebrated
“Introduction to Entomology,” a work which is distinguished by the
strain of rational piety and fervent devotion which it breathes, not
less than by its accurate scientific details, is charged (p. xxxviil. &c.)
with adopting (from Macleay) the atheism of Robinet ! The extreme
effrontery of this, (as we are sure all our readers will unite with us in
regarding it,) becomes more strikingly apparent, when we reflect that
the venerable naturalist thus accused was, not long since, selected to
produce one of the works to be published in demonstration of the Divine
Attributes, as manifested in the Works of the Creation, in pursuance
of the bequest of the late Earl of Bridgwater. That this was a pe-
culiarly appropriate selection, all who are acquainted with the works
of Mr. Kirby, will concur in thinking ; and what renders the most
unfounded attack upon him in the publication before us the more ex-
traordinary, is that it should proceed from a Professor in a College,
two of the Governors of which (the Archbishop of Canterbury and the
Bishop of London) concurred with the President of the Royal Society
(then Mr. Davies Gilbert) in the appointment of Mr. Kirby to the
above office *.—But to return to Mr. Rennie. Pursuing the same
strain, Messrs. Macleay and Kirby are actually both charged, in the

* See Phil. Mag. and Annals, N.S. vol. ix. p. 202.
page

374 Notices respecting New Books.

page last quoted, with assuming “that a stone has improved itself
into an oak, anda horse intoaman!” The idea of deviation in struc-
ture from a type previously discovered by an inductive process, or
that of the assemblage of characters which belong to the species form-
ing the aberrant groups of Mr. Macleay, is confounded in the work
before us with the notion of absolute imperfection and degradation in
the works of the Creator. The mental process by which we express
the gradual change of form and structure observable in the progres-
sion of affinities among animals, is mistaken by Mr. Rennie for the
actual physical conversion of one animal into another by the exercise
of its own volition, and Mr, Macleay is charged with advocating the
latter doctrine! The most philosophical and profound deductions of
the most eminent naturalists of all ages, are also stigmatized by him
as being nothing but the vagaries of fancy.

Finally, Mr. Rennie, rightly anticipating that he would be charged
with misrepresenting the Macleayan System, and the opinions of its
discoverer and advocates, attempts to excuse himself by confounding
his own groundless inferences with the mistakes regarding the sub-
ject, of certain naturalists whom he names, but whom we will not
degrade by naming unnecessarily in the same page with him.

We here terminate our indictment of Mr. Rennie at the bar of
scientific and literary justice, for the numerous misrepresentations of
fact, and misinterpretations of reasoning, of which the introductory
matter of his edition of Montagu’s Ornithological Dictionary is com-
posed ; and we proceed to state the process we have adopted in order
to obtain the evidence necessary to support our charges, and the
manner in which we intend to bring it forward.

Agreeably to Mr. Rennie’s invitation in p. xxi. we have weighed
“* every fact’’ which he has adduced ; we have “‘ rigidly” scrutinized
“every inference” he has made; and having found them wholly
‘* wanting in truth and accuracy,” ‘at once,”’ as he calls upon us to
do, ‘‘ without any compromise,”’ we ‘ reject them.” And, in accord-
ance with our duty as conductors of a scientific Journal, we intend,
by detailing the results of our weighing of facts and scrutiny of in-
ferences, to evince that our readers also must, “‘ without any com-
promise,” “ reject” Mr. Rennie and his works, as having any claim to
the attention of the cultivators or students of science, or to that of
the admirers of nature.

All the representations concerning Mr, Rennie’s mode of treating
the subjects he has undertaken to discuss, which are preferred in the
foregoing pages, we engage to substantiate in detail, refuting at the
same time such of his assertions as may appear to require it, in the
course of the present article. In doing this, we shall have occasion
to enter into an examination of certain errors respecting the ‘ new
views” in Natural History, which, as we conceive, have been com-
mitted by several contemporary naturalists ; but we shall most care-
fully distinguish their candid criticism and expression of their senti-
ments from the arrogant and baseless assertions of Mr. Rennie,
which involve the same fallacies of reasoning. We shall also en-

deavour, as we proceed, to explain and define, in their true characters,
the

Notices respecting New Books. 375

the views of natural arrangement of Mr. Macleay and his disciples,
so far as they have yet been enunciated ; noticing some differences
of opinion, on minor points, which exist among the naturalists of
this school. By this means we hope to convey a just idea of them to
the general reader ; for we wish to enlist every reflecting mind inter-
ested in the study of nature, in the support of the “ new views,”
confident alike of the delight which the truths they unfold will convey
to every person of common intellectual powers, and of the increased
stability they will be found to give to the deductions of a sound natu-
ral theology, harmonizing most perfectly with the Christian Religion.

For reasons which will be evident in the sequel, we begin with
Mr. Rennie’s attack on the Quinary System. This commences in
p- Xxxil. of his prefatory matter, and in the following page, under the
head “The Quinary System and Modern Doctrine of Types, Affinities,
and Analogies,” he ostensibly begins the consideration of the subject.
Mr.W. S. Macleay’s attempt to discover the natural system he states to
have been “ beyond all question, highly laudable,” though, ke con-
tinues, “1 shall endeavour to show, after giving a brief outline [of it],
it appears to be altogether a failure.” Mr. R. then gives an extract
from a review published in the Zoological Journal, and four extracts
from Mr. W. S. Macleay’s own works, for the purpose, apparently,
of supporting a representation which he makes at the outset, that the
“ system recently proposed,” to which he is about to advert, “on its
first announcement, put forth the high claim of being exclusively,—
if not the natural system, at least the rudiments thereof, or furnishing
the means for arriving at this, and, therefore, [of being] in accor-
dance with the plan of the Deity at the creation.”

Now with this representation of the character of the doctrine of the
circular succession of affinities and the parallelism of groups, (as we
shall for the present designate the system under examination, for the
particular number of the groups it discovers is merely a consequence
of its other principles,) we heartily concur. To maintain that the
arrangement discovered by Mr. Macleay is the entire system of nature,
—that it embraces the whole plan of the Deity at the creation, or
that errors may not exist in what Mr. Macleay or his followers may
have promulgated as the result of their observation of nature, would
be idle and absurd ; and we confidently affirm that such a view never
has been maintained either by Mr. Macleay or his disciples.

But we also affirm that the system first propounded, as a system,
by Mr. Macleay, and discovered by him (however certain constituent
principles of it might have been previously discovered by others) is as
much “the natural system” as the Copernican system of that assem-
blage of the heavenly bodies of which the planet we inhabit is one,
is ‘the natural system’’. Everything that proceeds from the mind or
the hands of man, is, in the universal sense of the term, artificial ;
for what is produced by the exertion of the human mental faculties,
or the human corporeal organization, cannot be natural, cannot be,
ipso facto, what exists in nature. But when nature is observed by man,
and when man expresses in language or by visible signs, his conception
of what he has thus observed in nature, the logical or predicative

system,

376 Notices respecting New Books.

system, or assemblage of observed truths, so produced, is, in the
language of science, the natural system. Thus what we call the
“‘ Copernican System” of nature, (truly, be it observed, a natural
system,) is not the actual assemblage of planetary bodies circulating
round the sun, of which our planet forms a part, but it is a represen-
tation of it, exactly corresponding to the truth; being all that man
can know of the reality. We make these remarks in this place, be-
cause much needless misapprehension, and also much unprofitable
discussion, have taken place on this part of the subject, and on the
right use of the phrase “the natural system’. The expression, by
man, of the truths he has discovered respecting the system of nature,
if that expression be itself true, is, in the just and legitimate sense of
the term, “the natural system”; being all that a finite being can know
or possess of it.

We further maintain that this is the sense, and the only sense, in
which the phrase “‘ the natural system”, and other equivalent terms,
have ever been used by Mr. Macleay and the naturalists of the mo-
dern British School of Zoology, of which he is the founder ; and that
it is the sense, and the only sense, of that phrase, and of the allu-
sions to the same subject, as employed in the extracts cited by Mr.
Rennie, in the page now before us.

In the extract from the review in the Zoological Journal, Mr. Mac-
leay is characterized as ‘‘ that profound zoologist who has succeeded
more effectually than any of his predecessors in unravelling the intri-
cacies of the system pursued by Nature in the distribution of the
animal kingdom”. What can be more explicit than this? the very
identical system propounded by Mr. Macleay is not regarded as being
“the system pursued by nature”, but he is said to have been more
successful than his predecessors in unravelling the intricacies of that
system ; just as we might say that Haiiy was more successful than his
predecessors in unravelling the intricacies of the system ‘‘ pursued by
nature” in the production of crystallized minerals ; or that Mr. Dal-
ton has been more successful than his predecessors in unravelling the
intricacies of the system ‘‘ pursued by nature” in the constitution of
chemical combinations.

Mr. Rennie’s statement insinuates, though it does not broadly af-
firm, that Mr. Macleay identifies his views with the actual system of
nature, as existing in nature; now this we positively deny, and we
deny too, that such a sense can be fairly or honestly extracted from
the passages quoted. After having examined the preface to the Hore
Entomologice, from which Mr. Rennie’s first two quotations are made,
we affirm that no approach to such an identification is contained in
it. The reader will observe that in these passages Mr. Macleay does
not once mention his own views, but merely places in apposition “an
artificial system” (understanding thereby any such system) and “ the
natural system ”’—‘‘ the plan of the creation itself—the work’of an
all-wise, all-powerful Deity”. But he would suppose, from the con-
nection in which the extracts are introduced by Mr. Rennie, that
where “the natural system” is mentioned in them, Mr. Macleay
means his own individual views. Than this, however, nothing can

be

Notices respecting New Books. 377

be further from the truth; Mr. Macleay does not, in the entire course
of his preface, even once either expressly make or indirectly imply
such an identification. He speaks throughout of the naturai system
as a thing which it is the end of the pursuit of natural history to dis-
cover, not as a thing yet discovered by any naturalist, and not at all
as having been discovered by himself. Nor can the assumption Mr.
Rennie would insinuate be discovered, (neither is it in the smallest
degree implied,) in the quotations which follow from Mr. Macleay’s
paper in the Transactions of the Linnean Society, and from his
“* Letter on the Dying Struggle of the Dichotomous System.”

But previously to our entering in detail upon this part of the sub-
ject, we must, for another purpose, quote and make some remarks upon
the remainder of this page of Mr. Rennie’s book ; it is as follows :—
** Again, speaking of his discovery of what he calls the nature of the
difference between affinity and analogy, Mr. Macleay says, ‘It is
quite inconceivable, that the utmost human ingenuity could make
these two kinds of relation tally with each other, had they not been so
designed at the Creation.’* In another place he talks of portions of
his svstem being ‘almost mathematically proved to be natural t.’”
The italics are all Mr. Rennie’s. We have in the extract now
before us, the first example of a numerous class of misinterpreta-
tions of the plainest figures and forms of speech in the English
language, which distinguish the present production of this champion,
before whose mighty prowess all the discoveries of modern zoology
are to be dispelled, like the illusions of fancy before the blaze of truth ;
a class of errors, which must either have resulted from wilful determi-
nation not to understand the representations of the New School of
Zoology, as they are used by their authors and designed to be under-
stood by them, or else the most deplorable and unpardonable igno-
rance of his own language, and of the figures common to all language,
which a claimant for literary or scientific honours ever yet displayed.
As we shall show in the sequel, the entire drift of this page, is to
support the assertion that Mr. Macleay’s system and ‘the natural
system’ are regarded to be identical. To contribute towards the
accomplishment of this purpose, Mr. Rennie puts the word nature
above, in italics, prefaced bya “what he calls,” meaning to insinuate
thereby that in the phrase “nature of the difference between affinity
and analogy” is contained an implication that that difference, is, ipso
facto, a part of “the natural system,” of the system actually existing
in nature. Whether this proceeds from effrontery or ignorance, it
is equally astonishing; had such a line of argument been related
to us of any writer, we should have denounced it as incredible, but
here it is before our eyes, and we can but wonder. In order
that no ambiguity or pretext for evasion may exist, we shall cite
the passage of the “Dying Struggle” in which the word is used
by Mr. Macleay. We shall, like Mr. Rennie, distinguish it by the
italic character. M. Virey and Dr. Fleming having both endea-

* Linn. Trans, quoted in “ Dying Struggle,” p. 26.
+ “ Dying Struggle,” p. 28.
N.S. Vol. 10. No, 59. Nov. 1831. 3C voured

878 Notices respecting New Books.

voured to fix upon Mr. Macleay the charge of plagiarism, with respect
to the distinction of relations of affinity from those of analogy, he
observes, “‘I have however repeatedly stated that Linneus, Pallas,
and Desfontaines, and even Aristotle himself, have all mentioned
certain analogies in nature, as distinct from affinities, before ] was
born. They have mentioned the existence of this distinction in par-
ticular cases ; but I first pointed out its nature and its general appli-
cation, and called the attention of naturalists to the subject.” Dying
Struggle, p. 25. Every reader whose progress in literature has ad-
vanced one step beyond ‘‘ The London Primer,’ and more especially
those who have ascended into the mysteries of that profound storehouse
of philology and rhetoric, “ Mavor’s Spelling Book,”’ will immediately
perceive what Mr. Macleay means by the word nature, where he uses
it the second time, which is that alluded to by his erudite antagonist.
Far be it from us to estimate the extent of Mr. Rennie’s attainments
as a man of letters; but as we are so unfortunate as to differ essen-
tially from him in opinion in our construction of this word, we must,
in our own vindication, explain our views on the point. When, there-
fore, Mr. Macleay employs the term “nature” of “the distinction of
relations of affinity from those of analogy,” we humbly conceive that
he does not intend to imply that the distinction between those rela-
tions is “ nature,” or the universe, as Mr. Rennie seems to think ;
any more than we intend, by saying that the nature of Mr. R’s attack
on the new views in Zoology is at once frivolous and unprincipled, to
imply the existence of nature, or anything like nature, in any of his
productions. Mr. Macleay means, that he first pointed out the Nature
(to employ the original Latin word, in the sense in which it is used
by Cicero and others) of the distinction between those two species of
relation, that is, its intimate quality and peculiar characters.

This subject, as it appears to us, illustrates another on which Mr.
Rennie enlarges in a previous page: ‘“‘On my plan [of the study of
Natural History,] any person,” he observes, ‘‘may become a tolera-
bly good naturalist, the first walk he takes in the fields, without much
knowledge of books :” in illustration of this plan of study, this mode
of making ‘‘tolerably good” naturalists with the rapidity of steam-
power, this new royal road to the knowledge of nature, or Professor
Rennie’s short cut to scientific fame, we are favoured in page x, by
a learned dissertation on the nest of a Dabchick, given as the great
type of the proper mode of conducting ornithological investigations,
But the author has unconsciously favoured us, in his construction
of the word “nature,” as above, with a memorable refutation of his
own principles of study: to us this is peculiarly consolatory ; for we,
obtuse wights as we are, were obliged, alas, to take a great many
‘“‘ walks in the fields,” and to pore over a great many books too,
before we thought ourselves “tolerably good naturalists.” But in
Mr. R’s mode of construing the word “nature” we now have an
example before us of the discovery of a phenomenon in nidification
far exceeding, in its wonderful character, what the Dabchick’s nest
would be, even were all the contradictory stories of it true; Mr.

Rennie, without even a single “walk in the fields,” has discovered
by

Notices respecting New Books. 379

by the mere study of books, that celebrated and interesting production
of nature, often discovered before, it is true, but always of equal
interest when rediscovered,—a Mare’s Nest-—We are not fond of
pleasantry in the discussions of science, but really this blunder is
worthy only of ridicule.

To return however to our examination of page xxxii. In the first
quotation from the Dying Struggle, Mr. Macleay certainly does
strongly affirm his opinion, that the two relations of affinity and ana-
logy co-exist in nature, (to which subject we shall by and by advert
in detail,) and were designed so to co-exist, at the Creation. But all
he asserts of himself, is, that he, by induction, discovered the nature
of the distinction between them, and also the nature of their co-exis-
tence ; and as truly might the Chemist who has observed that hydro-
gen, oxygen, and sulphur, enter into combination with each other or
with other bodies invariably in proportions represented by the num-
bers 1, 8, and 16, or their multiples by a whole number, say, “It is
quite inconceivable, that the utmost human ingenuity could make”
the proportions in which these bodies combine ‘‘ tally with each
other, had they not been so designed at the Creation.” He would de-
scribe in these terms, relations which the Creator has been pleased to
confer on certain forms of matter; Mr. Macleay does the same, but
he does no more ; neither does more or less, by using this language,
than describe an ascertained phenomenon. Similar is the case with
Mr. Macleay’s saying that the great groups into which he has disco-
vered the animal kingdom to be distributed, on its first ramification,
“are almost mathematically proved to be natural.” This is just the
expression which the chemist again might use, in the actual condition
of his science, respecting Dr. Prout’s doctrine that all the numbers
representing the proportional combining weights of the chemical ele-
ments are simple even multiples of the least of them; a doctrine
which ‘is almost mathematically proved to be natural.”

We quit the subjects of this introductory page, with the observa-
tion that the quotations in it have been made and arranged, either
disingenuously or ignorantly, to prove that Mr. Macleay’s system
claims to be ipso facto the system of nature: if such be not their de-
sign, they can have been intended for no purpose whatever, nor do

they serve any other, [To be continued.]
Sept. 29, 1831.

The Life of Sir Humeury Davy, Bart. LL.D. late President of the
Royal Society, Foreign Associate of the Royal Institute of France,
&ces &c. yy John Ayrton Paris, M.D. Cantab, F.R.S. Sc.
Fellow of the Royal College of Physicians.

[Continued from page 223.]

In the chapter which contains the account of the decomposition
of the fixed alkalies, notice is also taken of some of Davy’s ex-
periments’ and discoveries, which though of minor are still of great
importance ; to these, however, we shall but briefly allude. Among
them are an investigation of the nature of Antwerp blue, which
proved to be a mixture of Prussian blue and alumina; the pro-
duction of the vegetation of the carbon of the wick of a candle,

3C2 by

380 Notices respecting New Books.

by placing it between the wires of a battery; the repetition of
Gay-Lussac and Thénard’s very important process for preparing
potassium; and his attempts to decompose the earths. With respect
to the latter Dr. Paris remarks, ‘‘ his results were indistinct: they
could not, like the alkalies, be rendered conductors of electricity
by fusion, nor could they be acted upon in solution, in conse-
quence of the strong affinity possessed by their bases for oxy-
gen.” While engaged on this subject he received a letter from
Berzelius, announcing the fact that he, in conjunction with Pontin,
had decomposed barytes and lime by negatively electrizing mercury
in contact with them, and thus had obtained amalgams of the bases of
those earths: these experiments were repeated by Davy with many
in addition, and an account of them was read before the Royal
Society on the 30th of June 1808. The memoir was entitled
‘« Electro-chemical Researches on the Decomposition of the Earths;
with Observations on the Metals obtained from them, and on the
Amalgam of Ammonia.”

It will not be requisite to enter into a discussion on the nature
of the amalgam; the appearances which it presents have not been
explained. But that hydrogen and azote are metals, or contain any-
thing metallic, will scarcely now be maintained ; the amalgama-
tion is probably merely apparent, and the recent experiments of
Mr. Daniell tend to confirm this opinion.

In 1808 Davy read his third Bakerian Lecture; the title of it is
« An Account of some new Analytical Researches on the Nature of
certain Bodies, particularly the Alkalies, Phosphorus, Sulphur, Car-
bonaceous matter, and the Acids hitherto undecompounded ; with
some general Observations on Chemical Theory.” Of this excellent
paper Dr, Paris gives an analysis. So sanguine was Davy’s hope of
decomposing some substances which have even yet resisted analysis,
that he addressed a letter to Mr. Children during the progress of
his experiments; in which he says, ** I hope on Thursday to show
you nitrogen as a complete wreck, torn to pieces in different ways.”

In a letter to the above-named gentleman, dated September 23,
1809, we also meet with some opinions which subsequent investiga-
tions have by no means corroborated. “I doubt not,” he says, “‘ you
have found before this, as I have done, that the substance we mis-
took for sulphuretted hydrogen is telluretted hydrogen, very soluble
in water, combinable with alkalies and earths, and a substance
affording another proof that hydrogen is an oxide.” He says also,
«J find that taking ammonium as the basis of hydrogen, according
to the ideas which I stated, all the compounds will agree with the
suppositions that I mentioned to you, viz. eight cubic inches of hy-
drogen, two of oxygen, ammonia; four and two, water; four and
four, nitrogen; four and six, nitrous oxide; four and eight, nitrous
gas; four and ten, nitric acid.”

We need hardly observe that of the opinions here mentioned,
that only which we have printed in italics is to be found in his
«¢ Elements of Chemical Philosophy,” printed within three years
from the date of this letter.

This

Notices respecting New Books. 381

This Jetter contains also an account of an experiment upon which
its illustrious author most probably founded his opinion, now gene-
rally adopted, that oxymuriatic acid, as it was then called, is an ele-
mentary, or at any rate an undecomposed substance. ‘I have kept,”
he says, “charcoal white-hot by the Voltaic apparatus, in dry oxy-
muriatic acid gas for an hour, without effecting its decomposition.
This agrees with what I have before observed with a red heat. It
is as difficult to decompose as nitrogen, except when all its ele-
ments can be made to enter into new combinations.” The experi-
ments by which Davy demonstrated that oxymuriatic acid is an
undecomposed body, are detailed in various papers read before the
Royal Society. ‘The changes thus effected in the views of chemists
have been the subject of discussion with respect to the parties with
whom they originated. “As to the claim of priority,” Dr, Paris
remarks, “‘ which has been urged by several philosophers in favour
of the French chemists, Davy, in speaking of Gay-Lussac’s paper,
published in the dnnales de Chimie for July 1814, observes, that
‘ the historical notes attached to it are of a nature not to be passed
over without animadversion. M. Gay-Lussac states, that he and
M. Thénard were the first to advance the hypothesis that chlorine
was a simple body ; and he quotes M. Ampére as having enter-
tained that opinion before me. On the subject of the originality of
the idea of chlorine being a simple body, I have always vindicated
the claims of Scheele; but I must assume for’ myself the labour of
having demonstrated its properties and combinations, and of having
explained the chemical phenomena it produces; and I am in pos-
session of a letter from M. Ampére, that shows he has no claims of
this kind to make *,’”

Dr. Paris has we think settled the question by reference to printed
documents. “ Davy published his ‘Elements of Chemical Philoso-
phy’ in 1812, containing a systematic account of his new doctrines
concerning the combinations of simple bodies. Chlorine is there
placed in the same rank with oxygen, and finally removed from the
class of acids. In1813 M, Thénard published ‘the first volume of
his Traité de Chimie Elémentaire Théorique et Pratique,’ in which he
states the composition of oxymuriatic acid as follows :—‘ Composi-
tion. The oxygenated muriatic gas contains the half of its volume
of oxygen gas, not including that which we may suppose in muriatic
acid.’ It was not until the year 18J6 that, by a note in his fourth
volume, he appears to have at all relaxed in his attachment to the
old theory of Lavoisier and Berthollet; and it will presently ap-
pear that at the period above mentioned, iodine had been disco-
vered, and its analogies to chlorine fully established, by the saga-
city of Davy.”

In his ninth chapter, Dr. Paris gives an account of Davy’s “ Ele-
ments of Chemical Philosophy,” above alluded to, of various disco-
veries, and also of his work on Agricultural Chemistry. We cannot
afford room for any of the Doctor’s remarks on these subjects, but
recommend them as well worth perusal.

* Royal Institution Journal, vol. i. p. 283.

Dr.

$82 Notices respecting New Books.

Dr. Paris’s second volume commences with a subject of peculiar
interest ; we allude to the introduction of Mr, Faraday to Sir H.
Davy. Dr. Paris observes that “ it is said of Bergman, that he con-
sidered the greatest of his discoveries to have been the discovery
of Scheele. Amongst the numerous services conferred upon sci-
ence by Sir Humphry Davy, we must not pass unnoticed that kind
and generous patronage which first raised Mr. Faraday from ob-
scurity, and gave to the chemical world a philosopher capable of
pursuing that brilliant path of inquiry which the genius of his
master had so successfully explored.”

‘«« The circumstances which first led Mr. Faraday to the study of
chemistry, and by which he became connected with the Royal
Institution, were communicated to me by himself in the following
letter.”

“© To J. A. Paris, M.D.
“« My dear Sir, Royal Institution, Dec. 23, 1829.

«‘ You asked me to give you an account of my first introduction
to Sir H. Davy, which I am very happy to do, as I think the cir-
cumstances will bear testimony to his goodness of heart.

«“ When I was a bookseller’s apprentice, I was very fond of ex-
periment, and very averse to trade. It happened that a gentleman,
a member of the Royal Institution, took me to hear some of Sir
H. Davy’s last lectures in Albemarle-street, I took notes, and af-
terwards wrote them out more fairly in a quarto volume.

«« My desire to escape from trade, which I thought vicious and
selfish, and to enter into the service of science, which I imagined
made its pursuers amiable and liberal, induced me at last to take
the bold and simple step of writing to Sir H. Davy, expressing my
wishes, and a hope that, if an opportunity came in his way, he would
favour my views; at the same time I sent the notes I had taken at
his lectures.

« The answer, which makes all the point of my communication,
I send you in the original, requesting you to take great care of
it, and to let me have it back; for you may imagine how much I
value it.

* You will observe that this took place at the end of the year
1812, and early in 1813 he requested to see me, and told me of the
situation of assistant in the laboratory of the Royal Institution, then
just vacant.

«< At the same time that he thus gratified my desires as to scien-
tific employment, he still advised me not to give up the prospects
I had before me, telling me that science was a harsh mistress ; and,
in a pecuniary point of view, but poorly rewarding those who de-
voted themselves to her service. He smiled at my notion of the
superior moral feelings of philosophic men, and said he would leave
me to the experience of a few years to set me right on that matter.

«« Finally, through his good efforts I went to the Royal Institu-
tion early in March of 1813, as assistant in the laboratory ; and in
October of the same year, went with him abroad as his assistant in
experiments and in writing. I returned with him in April 1815,

resumed

Notices respecting New Books. $83

resumed my station in the Royal Institution, and have, as you
know, ever since remained there.
« T am, dear Sir, very truly yours, M. FarapDAy.”

The following is the note of Sir H. Davy, alluded toin Mr. Fara-

day’s letter :
“* To Mr. Faraday.
« Sir, December 24, 1812,

“I am far from displeased with the proof you have given me of
your confidence, and which displays great zeal, power of memory,
and attention. Iam obliged to go out of town, and shall not be
settled in town till the end of January: I will then see you at any
time you wish.

*«« It would gratify me to be of any service to you. I wish it may
be in my power.

« ] am, Sir, your obedient humble Servant,
“H. Davy.”

The invention of the safety-lamp is a subject upon which Dr.
Paris has treated at considerable length, and his account is inter-
spersed with details of great interest.

In consequence of some dreadful explosions which had occurred
in the coal-mines of the North of England, a society was formed
for preventing their recurrence, by inviting the attention of sci-
entific men to the subject, and obtaining from them any sugges-
tions which might lead to a more secure method of lighting the
mines.

«To the Rey. Dr. Gray, the present Lord Bishop of Bristol,”
says Dr. Paris, “who, at the period to which I allude, was the
Rector of Bishop-Wearmouth, and one of the most zealous and in-
telligent members of the Association, | beg to offer my public ac-
knowledgements and thanks for the several highly interesting com-
munications and Jetters with which His Lordship has obliged me ;
and by means of which I have been enabled to present to the sci-
entific world a complete history of those proceedings which have
so happily led to a discovery, of which it is not too much to say
that it is, at once, the pride of science, the triumph of humanity,
and the glory of the age in which we live.”

Having received a letter from Dr. Gray, as chairman of the Asso-
ciation, to engage him in an investigation of the subject, the fol-
lowing was Davy’s answer.

“ To the Reverend Dr. Gray.
“ Sir, August 3, 1815.

“I had the honour of receiving the letter which you addressed
to me in London, at this place, and I am much obliged to you for
calling my attention to so important a subject.

“ It will give me great satisfaction if my chemical knowledge can
be of any use in an inquiry so interesting to humanity; and I beg
you will assure the committee of my readiness to co-operate with
them in any experiments or investigations on the subject.

“ If you think my visiting the mines can be of any use, I will
cheerfully do so.

« There

384 Notices respecting New Books.

«‘ There appears to me to be several modes of destroying the
fire-damp without danger ; but the difficulty is to ascertain when it
is present, without introducing lights which may inflame it. I have
thought of two species of lights which have no power of inflaming
the gas which is the cause of the fire-damp, but I have not here
the means of ascertaining whether they will be sufficiently lumi-
nous to enable the workmen to carry on their business. They can
be easily procured, and at a cheaper rate than candles.

«I do not recollect anything of Mr. Ryan’s plan: it is possible
that it has been mentioned to me in general conversation, and that
I have forgotten it. If it has been communicated to me in any other
way, it has made no impression on my memory.

* I shall be here for ten days longer, and on my return south,
will visit any place you will be kind enough to point out to me,
where I may be able to acquire information on the subject of the
coal gas.

“ Should the Bishop of Durham be at Auckland, I shall pay my
respects to His Lordship on my return.

«T have the honour to be, dear Sir, with much respect, your
obedient humble Servant, H. Davy,”

* At Lord Somerville’s, near Melrose, N. B.

Although Sir Humphry did not immediately commence his ope-
rations after writing this letter; yet such was the vigour with which
he prosecuted them, that in October he wrote the following letter
to Dr. Gray:

* To the Reverend Dr, Gray.

«« My dear Sir, Royal Institution, Oct. 30.

‘‘ As it was the consequence of your invitation that J endeavoured
to investigate the nature of the fire-damp, I owe to you the first
notice of the progress of my experiments.

«« My results have been successful far beyond my expectations.
I shall inclose a little sketch of my views on the subject; and I hope
in a few days to be able to send a paper with the apparatus for the
committee.

«[ trust the Safe lamp will answer all the objects of the col-
lier.

«‘ I consider this at present as a private communication, I wish
you to examine the lamps I have had constructed, before you give
any account of my labours to the committee.

‘«‘ T have never received so much pleasure from the result of any
of my chemical labours; for I trust the cause of humanity will
gain something by it.

«<I beg of you to present my best respects to Mrs. Gray, and to
remember me to your son. é

« I am, my dear Sir, with many thanks for your hospitality and
kindness when I was at Sunderland, your obliged Servant,

“ H, Davy.”

The sketch alluded to in this letter is as follows: ‘ It possesses,”
Dr. Paris justly remarks, ** considerable interest as an original do-

cument,

Notices respecting New Books. 385

cument, displaying his earliest views, and tending to illustrate the
history of their progress.”

“ The fire-damp I find, by chemical analysis, to be (as it has
been always supposed) a hydro-carbonate. It is a chemical com-
bination of hydrogen gas and carbon, in the proportion of 4 by
weight of hydrogen gas, and 114 of charcoal.

«¢T find it will not explode, if mixed with less than six times, or
more than fourteen times its volume of atmospheric air. Air,
when rendered impure by the combustion of a candle, but in which
the candle will still burn, will not explode the gas from the mines ;
and when a lamp or candle is made to burn in a close vessel having
apertures only above and below, an explosive mixture of gas ad-
mitted merely enlarges the light, and then gradually extinguishes it
without explosion. Again,—the gas mixed in any proportion with
common air, I have discovered, will not explode in a small tube, the
diameter of which is less than 4th of an inch, or even a larger tube,
if there is a mechanical force urging the gas through this tube.

«« Explosive mixtures of this gas with air require much stronger
heat for their explosion than mixtures of common inflammable
gas*. Red-hot charcoal, made so as not to flame, if blown up by
a mixture of the mine gas and common air, does not explode it,
but gives light in it; and iron, to cause the explosion of mixtures
of this gas with air, must be made w/zte-hot.

‘“« The discovery of these curious and unexpected properties of
the gas leads to several practical methods of lighting the mines
without any danger of explosion.

“The first and simplest is what I shall call the Safe lamp, in
which a candle or a lamp burns in a safe lantern, which is air-tight
in the sides, which has tubes below for admitting air, a chamber
above, and a chimney for the foul air to pass through; and this is
as portable as a common lantern, and not much more expensive.
In this, the light never burns in its full quantity of air, and there-
fore is more feeble than that of the common candle,

“ The second is the Blowing iamp. In this, the candle or lamp
burns in a close lantern, having a tube below of small diameter for
admitting air, which is thrown in by a small pair of bellows, and a
tube above of the same diameter, furnished with the cup filled with
oil. ‘This burns brighter than the simple safe lamp, and is extin-
guished by explosive mixtures of the fire-damp. In this apparatus
the candle may be made to burn as bright as in the air; and sup-
posing an explosion to be made in it, it cannot reach to the ex-
ternal air.

“ The third is the Piston lamp, in which the candle is made
to burn in a small glass lantern furnished with a piston, so con-

* “ Olefiant gas, when mixed with such proportions of common air as to
render it explosive, is fired both by charcoal and iron heated to a dull-red
heat. Gaseous oxide of carbon, which explodes when mixed with two parts
of air, is likewise inflammable by red-hot iron and charcoal. The case is
the same with sulphuretted hydrogen.”

N. S. Vol. 10. No. 59. Nov. 1831. 3D structed

386 Notices respecting New Books.

structed as to admit of air being supplied and thrown into it with-
out any communication between the burner and the external air:
this apparatus is not larger than the steel-mill, but it is more ex-
pensive than the other, costing from twenty-two to twenty-four
shillings.

«« These lamps are all extinguished when the air becomes so pol-
luted with fire-damp as to be explosive.

«« There is a fourth lamp, by means of which any blowers may be
examined in air in which respiration cannot be carried on: that is,
the Charcoal lamp. This consists of a small iron cage on a stand,
containing small pieces of very well burnt charcoal blown up to a
red heat. This light will not inflame any mixtures of air with fire-
damp *.

«‘ Of these inventions, the Safe lamp, which is the simplest, is
likewise the one which affords the most perfect security, and re-
quires no more care or attention than the common candle, and
when the air in mines becomes improper for respiration, it is ex-
tinguished, and the workmen ought immediately to leave the place
till a proper quantity of atmospheric air can be supplied by venti-
lation.

«‘ I have made many experiments on these lamps with the ge-
nuine fire-damp taken from a blower in the Hepburn Colliery, col-
lected under the inspection of Mr. Dunn, and sent to me by the
Rev. Mr. Hodgson. My results have been always unequivocal.

«« T shall immediately send models of the different lamps to such
of the mines as are exposed to danger from explosion; and it will
be the highest gratification to me to have assisted by my efforts a
cause so interesting to humanity.”

The Safety lamp as now perfected, and the principle upon which
the safety depends, are so well known as to require no further elu-
cidation. We fully agree with Dr. Paris, that “ it was the fruit of
elaborate experiment and close induction ; chance, or accident,
which comes in for so large a share of the credit of human inven-
tion, has no claims to prefer upon this ocdiision: step by step may he
be followed throughout the whole progress of his research, and so
obviously does the discovery of each new fact spring from those
that preceded it, that we never for a moment lose sight of our phi-
losopher, but keep pace with him during the whole of his curious
inquiry.”

[To be continued.]

* “Tn addition to these four lamps, we learn from an Appendix to his
paper in the Philosophical Transactions, that in the beginning of his in-
quiries, he constructed a close lantern, which he called the Fire-valve
lantern; in which the candle or lamp burnt with its full quantity of air,
admitted from an aperture below, till the air began to be mixed with fire-
damp, when, as the fire-damp increased the flame, a thermometrical spring
at the top of the lantern, made of brass and steel, riveted together, and in a
curved form, expanded, moved a valve in the chimney, diminished the cir-
culation of air, and extinguished the flame. He did not, however, pursue
this invention, after he had discovered the properties of the fire-damp, on
which his Safety-lamp is founded.”

XLIX, Pro-

XLIX. Proceedings of Learned Societies.

BRITISH ASSOCIATION FOR THE PROMOTION OF SCIENCE,
Instituted September 22, 183].

aS our next Number we intend to give a full account of the pro-

ceedings of this Association, at the meeting lately held at York ;
—we shall now lay before our readers a summary of its objects and
rules.

Oxssects.—The Association contemplates no interference with the
ground occupied by other Institutions. Its objects are,—to give an
additional impulse and a systematic direction to scientific inquiry,—
to promote the intercourse of those who cultivate science in different
parts of the British empire with one another and with foreigners,—
to obtain a more general attention to the objects of science, and a
removal of any disadvantages of a public kind which impede its pro-
gress.

Rutrs.—All persons who have attended the first meeting shall be
entitled to become Members of the Association, upon subscribing an
obligation to conform to its rules. The Fellows and Members of
chartered Societies in any part of the British empire shall be entitled
in like manner to become Members of the Association. The Office-
bearers and Members of the Council or Managing Committee of all
Philosophical Institutions, and other members of such Institutions
recommended by the Council, or Managing Committee thereof, shall
be entitled in like manner to become Members of the Association.
Persons not belonging to such Institutions shall be eligible annually
on the recommendation of the General Committee.

The names of persons desiring to become members shall be en-
rolled, and their subscriptions received by the Secretaries and Trea-
surer. The amount of the annual subscription shall be 1/., to be
paid in advance upon admission, and the amount of the composition
in lieu thereof, 51.

The Association shall meet annually for one week or longer. The
place of each meeting shall be appointed by the General Committee
at the previous meeting, and the arrangements for it shall be entrusted
to the officers appointed at the preceding meeting in concert with the
Local Committees.

The Genera Commirree shall sit during the time of the meeting,
or longer, to transact the business of the Association. It shall con-
sist of all Members present who have communicated any scientific
paper to a Philosophical Society, which paper has been printed in its
Transactions, or with its concurrence. The members of Philosophical
Institutions, who may be sent as deputies from those Institutions to
any Meeting of the Association, shall be members of the Committee
for that Meeting.

The General Committee shall appoint annual Sus-Commrrresrs,
consisting severally of the members most conversant with the several
sciences, to advise together for the advancement thereof. ‘The Sub-
Committees shall report what subjects of investigation they would

3D2 particularly

388 British Association for ihe Promotion of Science.

particularly recommend to be prosecuted during the ensuing year,
and brought forward at the ensuing meeting ; they shall also engage
their own members, or others, to undertake such investigations, and
where the object admits of being assisted by the exertions of scientific
bodies, they shall state the particulars in which it may be desirable
for the Committee to solicit the cooperation of such bodies. The
Sub-Committees shall procure reports on the state and progress of
the several sciences, to be drawn up by competent persons for the in-
formation of the Meetings.

The Committee shall appoint at each Meeting a Sub-Committee
to examine the papers which have been read at it, and the register of
Communications, and to report what ought to be published, and
recommend the manner of publication. The author of any paper or
communication shall be at liberty to reserve his right of property
therein.

Locat Commirress shall be formed, where necessary, by the Com-
mittee, or by the Officers of the Association, to assist in promoting its
objects.

The Orricers of the Association,—namely, a President, two Vice-
Presidents, two or more Secretaries and a Treasurer,— shall be an-
nually appointed by the Committee.

The Accounts shall be audited annually by Auditors appointed by
the Meeting.

OFFICERS OF THE ASSOCIATION,

Presipent, Viscount Milton, F.R.S. &c. Prestpenr Euecr,
Rev. W. Buckland, D.D. F.R.S. &c. Prof. of Geology and Mine-
ralogy, Oxford. Vice-Presipent, Rey. W. Vernon Harcourt,
F.R.S. &c. Vicr-Prestpents Execr, David Brewster, LL.D.
F.R.S. L.& E. Corr. Member of the Institute of France; Rev.
W. Whewell, F.R.S. &c. Prof. of Mineralogy, Cambridge.

Secretaries, Wm. Gray, jun. Secretaries of the Yorkshire

John Phillips, F.G.S. vey Philosophical Society, York.

Ch. Daubeny, M.D. F.R.S. &c. Professor of Chemistry,
Oxford.

Rev. B. Powell, F.R.S. &c. Sav. Professor of Mathe-
matics, Oxford.

John Robison, F.R.S. &c. Secretary of the Royal So-
ciety E., Edinburgh.

Rey. J. Yates, F.L.S. &c. London.

Locat CommitTELEs.

Lonvon ....G. B, Greenough, F.R.S. Vice-Pres. of the Geol. Soc.
R. I. Murchison, F.R.S. President of the Geol. Society.
Rev. James Yates, F.L.S. &c.

EpinpureH. James D. Forbes, F.R.S. &c.
J. F. W. Johnston, F.R.S.E.
John Robison, Sec. R.S.E.

Dusiin ..,. W. R. Hamilton, F.R.S. &c. Royal Astronomer of

Ireland.

Rey, Dr. Lioyd, F.R.S. Provost of Trinity College.

InpiA.

Zoological Society. 389

Inp1a .. .. George Swinton, Esq. Chief Secretary to the Government in
India, has been requested to form a Committee at
Calcutta, with the aid of Major Benson, James
Calder, Esq., Dr. Christie, Sir Edward Ryan,
J. A. Prinsep, Esq. and J. Herbert, Esq.

We shall give in our next Number the names of the members of
the Sub-Committees, and the subjects of scientific inquiry which they
have proposed. In the mean while we have the pleasure to state, that,
at the request of the Association, Professor Airy has undertaken to
prepare a Report on the state and progress of Astronomy; Dr. Brew-
ster a similar Report on Optics ; Professor Whewell on Mineralogy ;
Mr. Johnston on Chemistry; and Mr. Forbes on Meteorology.

ZOOLOGICAL SOCIETY.

July 26, 1831.—Dr. Marshall Hall in the Chair.

Specimens were exhibited of two Mammalia, presented to the So-
cigty by J. Boyle, Esq., Colonial Surgeon, Sierra Leone. They were
the remains of animals which died on their passage homewards, and
had unfortunately been put after death, into brine too weak for their
perfect preservation. Since their arrival at the Museum they had
been transferred to strong spirit, with the view of preserving as com-
pletely as their then state would permit, specimens of so much in-
terest. One of them was stated by Mr. Bennett to be a fully grown
Aulacodus Swinderianus, Temm.; the other a Lemuridous species,
which is probably the animal noticed and imperfectly represented
by Bosman under the name of Potto. The latter was shown to be
the type of a new genus, which Mr. Bennett characterized as follows :

PrRopicricus.

Facies subproducta. Artus subequales, Cauda mediocris. Index bre-
vissimus, phalange ungueali solum exserto. -Dentes primores su-
perne 4, subequales ; inferné 6, graciles, declives : canini, + +, co-
nici, compressi, marginibus antico posticoque acutis: molarium
in mazilld superiore primus minimus; secundus major; ambo
conici; tertius acuté tuberculatus, tuberculis duobus externis alte-
roque interno; quartus precedenti similis tuberculo interno majore ;
sequentes (in specimine juniore desunt) ; in maxilld inferiore, duo
conici e@quales ; tertius acute externe 2-, intern? 1-tuberculatus,
sequentes (desunt).

Peropicricus Grorrroyi. Per. castaneus, infra pallidior, pilis
raris cinereis interjectis : vellere lanato.

Potto, Bosman, Guin. ii. 35. No. 4?

Lemur Potto, Gmel., Linn. Syst. Nat. 42 ?

Nycticebus Potto, Geoff, Ann. Mus. xix. 165?

Galago Guineensis, Desm. Mamm. 104, No. 127 ?

Hab. in Sierra Leone.

The head is rounded, with a projecting muzzle: the nostrils are
lateral, small, sinuous, with an intermediate groove extending to the
upper lip: the tongue is rough with minute papille, rather large,
thin and rounded at the tip, and furnished beneath with a tongue-

like

390 Roological Society.

like appendage, which is shorter than the tongue itself and terminates
in about six rather long lanceolate processes, forming a pectinated
tip ; the eyes are small, round, somewhat lateral, and oblique: the
ears moderate, open, slightly hairy, both within and without. The
body is rather slender. The limbs are nearly equal, long, and slender:
the fingers moderately long. On the fore-hands the index is exces-

sively short, the first phalanx being concealed, and the ungueal pha-
lanz (the only phalanz free) being barely large enough to support a
rounded nail, which does not exist on the specimen, but of which
there is an apparent cicatrix; the nails of all the other fingers are
fiat and rounded. Those of the hinder hands are similar, except that
of the fure-finger, which, as in the Lemurs generally, is long, subulate,
and curved. ‘The tail is of moderate length, and covered with hairs
resembling those of the body. The hairs generally are long, soft,
and woolly; each of them being mouse-coloured at the base ; rufous
in the middle, and paler at the tip; some few are tipped with white.
Hence results on the upper surface and on the outsides of the limb a
chestnut colour with a slight mixture of grey: the under surface is
much paler. The muzzle and chin are almost naked, having only a
few scattered whitish hairs.

The measurements of the specimen are: length of the head, 2
inches 2 tenths ; of the body, 6 inches ; of the tail, 1 inch 6 tenths,
or including the hair, 2 inches 3 tenths. The breadth of the head in
front of the ears is 1 inch 4 tenths: the distance between the eyes,
4 tenths ; from the anterior angle of the eye to the end of the nose,
7 tenths ; from the eye to the ear, 71 tenths: length of ears be-
hind, 5, of their aperture 8, breadth 5 tenths of an inch.

Anterior Limbs. Posterior Limbs.

in. in,
humerus pA ernest FOMET a 40 seh. “alee ne ast Paienne
ulna. 231) 2tbia ne, ooh jaa

carpus to end of 4th (longest) from os calcis to end of 4th
finger . 18 (longest) finger . . . 23
‘amb with metacarpal bone 1-0 | thumb with metatarsal bone 1°]
fore-finger . ‘4 | fore-finger OPE nail 2° =) ‘8
— last joint (all that is ‘free) 1 | 3rd finger Ms "9
SPA MINBER A n'y own enn | 4s ‘9 | 4th finger a9 tohy eM aise meee
Sth gioverye..) feansa- Ae ceded both finger.’ cal. s2. si “9
Sth finger Oy spans os ycwes) 24a

BPA © pode Mie Sw Ae Stes iny) (S'4
By the comparative length of the tail the genus Perodicticus is
readily distinguishable from the other Lemuride. In this, in the mo-
derate elongation of the face, in the moderate size of the ears, in the
equality of the limbs, and especially in the extreme shortness of the
index of the anterior hands, reside its essential characters. The
latter character is especially important, and may be regarded as indi-
cating its typical station in a family, all of which are distinguished
from the neighbouring groups by a variation in the form of the index
or of its appendages. In the Lemuride generally the nail of the
index of the hinder hands is elongated and claw-shaped, and unlike
those

Roological Society. 391

those of the other fingers, which are flat as in the Monkeys. This is
frequently accompanied by an abbreviation of the index of the fore-
hands, which becomes in Loris, Geoff., very considerable, and is in
Perodicticus carried to its maximum, that organ being here almost
obsolete.

The habits of the anitmal are described by Mr. Boyle as “slothful
and retiring. It seldom makes its appearance but in the night time,
when it feeds upon vegetables, chiefly,” he believes, ‘the Cassada.
It is known to the colonists as the Bush- Dog.”

The specimen of dulacodus, being fully adult, was shown to add
much to the knowledge previously possessed of an animal, only one
individual of which had hitherto been seen by naturalists, and that
individual so young as not to have attained its perfect characters.
Mr. Bennett pointed out the deviations, in the specimen exhibited,
from the description published by M. Temminck in his ‘ Monogra-
phies de Mammalogie’, and proposed the following amended generic
character :

Avuxacopus, Van Swind.

Dentes incisores 3, anticé plani, scalpro cuneato, superiores profunde
bisulcati: molares ++, lamellares: sacculi buccales 0 : pedes an-
tict digitis 4, cum rudimento pollicis ; postici digitis 4: ungues,
preter pollicis subplanum, falculares, fortes, superné rotundati,
infra dilatati suleati: cauda pilosa, mediocris, attenuata.

The deep sulci on the anterior surface of the incisor teeth of the
upper jaw are situated nearer to the inner than to the outer edge of
the tooth, and divide its face into three ridges, the inner of which is
half the breadth of the middle, and the middle less than half the
breadth of the outer. The molar teeth of the upper jaw have two re-
entering folds of enamel on the outer, and one on the inner side ; the
outer passing beyond the middle of the crown, the inner central and
less deeply entering : all the teeth are nearly equal in size : the an-
terior three are nearly square; the posterior somewhat rounded :
there is no notching on the outer edge, but a distinct notch exists
where the enamel folds in on the inner side, especially of the three
posterior teeth. In the lower jaw the first molar has three folds of
enamel on the inner side passing beyond the middle of the crown,
and one small foid slightly notched on the outer: the second and
third have two inner folds and one outer, all notched at the edge:
the posterior is nearly similar, but more rounded behind. This system
of dentition bears a greater resemblance to that of Erethizon, F. Cuv.,
than to that of any other genus of the Rodentia.

The covering of the Aulacodus Swinderianus is peculiar, consisting
entirely, except on the tail, of fiattened somewhat spine-like bristles,
from | to I+ inch in length, the tips only of which are flexible and
hair-like ; the dark space which occupies the greater portion of each
of the bristles exhibits a changeable metallic lustre, varying in differ-
ent positions from deep steel blue to bright copper red.

The length of the body and head is 17 inches, or measured along
the convexity of the back, 20: of the tail, 9: of the head, 44: of the
fore-leg, 34; tarsus and toes, 1+: of the femur, 44; tibia, 44; tarsus

and

392 Intelligence and Miscellaneous Articles.

and toes, 33: the ear, nearly concealed by the bristly covering, is
12 long, and | inch broad.

Mr. Boyle states that this animal “is called by some the Ground-
Pig, by others, the Ground-Rat. It feeds upon ground nuts, Cassada,
and other roots. On the passage homewards it ate potatoes, and.was
becoming very docile.”

It is very probably the “wild Rat, bigger than a Cat” mentioned
by Bosman.

A small collection of Fishes, formed during the voyage of H. M. S.
Chanticleer, and presented to the Society by the Lords Commission-
ers of the Admiralty, together with numerous other Zoological spe-
cimens obtained during the same voyage, was laid upon the table.
It contained among others a young individual of the Scyllium cirra-
zum, in the state in which it is described by Schneider as the Squalus
ounctatus ; a specimen of the Blennius pilicornis, Cuv., described ori-
ginally by Marcgrave, and remarkable for the long acicular tooth at
the back of the lower jaw on each side, a peculiarity which may here-
after cause it to be regarded as the type of a distinct genus : a spe-
cimen of the Antennarius scaber, Chironectes scaber, Cuv., also de-
scribed by Marcgrave : and two species which appeared to be new to
science, and which were thus characterized by Mr. Bennett :

Curomis Tznia. Chrom. brunneo-nigrescens : pinnis nigrescentibus
caudali subrotundatd nigro fasciatim punctatissinad: macula ro-
tundd infraoculari, altera ad basin pinne caudalis superne, t@-
nidque ab oculo per medium latus ad pinnam caudalem ductd,
nigris.

D.4¢. A. 4%. P2113. C..16.

Hab. apud Trinidad.

Affinis Chrom. punctato, Cuv., (Labrus punctatus, L.). Differt a
figura Blochiana tenia laterali, pinnisque haud lineatis: differt etiam
numero radiorum pinnarum.

Monacanruus setirer. Mon. caudé hispida : cirris brevibus mul-
tifidis raris conspersus: pinne dorsalis radio 2do longissimo :
pallidé brunneus, lateribus mediis nigro undulatim longitudinaliter
lineatis : pinne caudalis rotundate fascid angusta submedia.

Dek, 28. Au 29 ColBiy BLUE

A description, by the Rev. Robert Holdsworth, of a fish taken in the
seine, at Start Bay, on the south coast of Devon, in August 1825,
was read. Mr. Holdsworth regards the fish in question as the Um-
brina, Sciena Aquila, Cuv.; with which species, occasionally taken in
the English Channel, his description agrees.

L. Intelligence and Miscellaneous Articles.

ON THE ATOMIC WEIGHT OF BARYTES. BY DR. THOMSON.

J I HAD from a set of experiments in which dry chloride of barium
was decomposed by sulphate of potash, inferred that the atomic
weight of pace 2 was 9°75. The conclusion was founded upon this
experiment: 13°25 grains of chloride of barium were mixed with
1] grains

Intelligence and Miscellaneous Articles. 393

1] grains of sulphate of potash, both in solution ; and it was found
that after the sulphate of barytes had precipitated, the residual
liquid contained no sensible quantity of sulphuric acid or of barytes.
Berzelius in the third volume of his Larbok i Kemien, stated that
when these proportions were used, there always remained an excess
of barytes. 1 requested several of my practical pupils to repeat the
experiment without mentioning my object, and they all gave me the
same proportions of the two salts that I had previously stated. I was
induced in April 1828 to try the experiment anew, and for this pur-
pose prepared a quantity of pure chloride of barium and of sulphate
of potash. After repeating the experiment about thirty times, varied
in every possible way, I found myself quite unable to determine the
exact proportions of the two salts which decompose each other.
There was no difficulty in finding the proportions which, when mixed
together, leave no sensible residue of sulphuric acid and barytes in
solution. But when I attempted to collect the sulphate of barytes
and chloride of potassium, I never found the quantities to agree in
any two consecutive experiments. Suspecting that the method of
using double filters might be the cause of the uncertainty, I substi-
tuted single filters of Indian paper, which were finally burnt in pla-
tinum crucibles. I was therefore obliged to give up the attempt of
determining the atomic weight of barytes by this method. Dr. Turner
has since explained the cause of this failure, which indeed I suspected
at the time. It is owing to a portion of the sulphate of potash adhe-
ring obstinately to the sulphate of barytes, and thus escaping decom-
position *. Foiled in this, 1 substituted sulphate of ammonia, and
afterwards sulphuric acid. By mixing a solution, containing a given
weight of chloride of barium with an excess of sulphate of ammonia
or of sulphuric acid, evaporating to dryness, and then exposing the
residual salt to a strong red heat, I succeeded in determining the
weight of sulphate of barytes, which is the equivalent for a given
weight of chloride of barium. The same weight of chloride of barium
was afterwards decomposed by nitrate of silver, and the weight of
chlorine determined from my old data that chloride of silver is a
compound of

STR Ae Ot eae 13°75
Chlorine ..... ere nS os 45
18°25

The result of these trials (which occupied me for several weeks) was,
that sulphate of barytes is a compound of

Sulphuric acid ,.........+. 5
BAPyUES,.< o\o-v'c.ceicecs onsets 95006

Now as 5 is the atomic weight of sulphuric acid, it is clear that 9-5
must be the atomic weight of barytes.”—System of Chemistry, (In«
organic Bodies,) 1831. vol. i. p. 426.

Dr. Thomson observes that these experiments are confirmed by

* Phil. Mag. and Annals, N.S., vol, viii. p. 183.
N.S. Vol. 10, No, 59. Nov, 1831. 3D those

394 Intelligence and Miscellaneous Articles.

those of M. de Saussure, which do not differ so much as +3!>¢ from
his.— Ann. de Chim. et de Phys. vol. xliv. p. 27.

Hydrogen being unity, Dr. Thomson's number for barytes will be
76 instead of 78 as he formerly determined; his present analysis
nearly coincides with that of Berzelius. The following are the results
of the three chemists mentioned.

Dr. Thomson. De Saussure. Berzelius.

Acid. dbeke 34°49 34:48 34°31
Base ssseue 65°51 G5:52 65°59
100:00 100-00 100-00 Epir.

ON THE OXICHLORATES. BY M. SERULLAS.

M. Serullas concludes from his experiments, Ist. That oxichloric
(perchloric) acid forms with potash a very slightly soluble salt, re-
quiring 65 times its weight of water at the temperature of 60° Fahr.

2nd, That soda forms with the same acid a very deliquescent salt,
which is consequently very soluble in water, and even in the strongest
alcohol.

3rd. That properties so opposite and decided, afford a method of
separating potash and soda when in solution ; the latter yielding, as
has been already stated, an oxichlorate very soluble in concentrated
alcohol, and the former an oxichlorate which is absolutely insoluble
in it.

4th. That in the same experiment any acid may be separated from
the potash which is combined with it; the acid being always set at
liberty by the oxichloric acid.

5th. That the employment of oxichlorate of silver for the mixtures
of the chlorides of sodium and potassium, and the employment of
oxichlorate of barytes for the mixture of the sulphates of these two
bases, renders it, by the intervention of alcohol, extremely easy to
separate all the elements completely.

Oxichlorate of potash is composed of

1 Be OTe WE (RRNA AERC inp od 34°275
PIAS OC yerie eects es Actes sheroue vein: 65.725
100:000

As bitartrate of potash is soluble in 60 parts of water, and oxichlo-
rate requires 65, oxichloric acid when added to a saturated solution
of the bitartrate occasions slight precipitation.

Oxichlorate of barytes is deliquescent, very soluble in water and
in alcohol; the solution when evaporated in a stove yields long
prismatic crystals ; paper impregnated with the solution burns with a
fine green flame. It is composed of

AGIA) Sa hee Tos bs 54°423
Base) aseue IBAA dt RHEL aie 45:577
100:000

When

Intelligence and Miscellaneous Articles. 395

When heated to redness in a tube it loses about 38-102 per cent, or
seven atoms of oxygen from the acid, and one atom from the base.

Oxichlorate of Strontia—When the solution is evaporated to the
consistence of a syrup, it assumes on cooling a mass of a crystalline
appearance, which readily attracts moisture from the air. It vives a
fine purple to flame.

Oxichlorate of Lime.—This salt is deliquescent ; when evaporated
to the consistence of a syrup it solidifies into a crystalline mass. It is
soluble in alcohol, and burns with a reddish flame.

Oxichlorate of Magnesia —Deliquescent, soluble in alcohol, and
crystallizes in long prisms ; oxichlorate of alumina reddens litmus
paper, although excess of gelatinous alumina has been used in pre-
paring it ; it does not crystallize, and is soluble in alcohol.

Orichlorate of Lithia.—It is prepared like the preceding salts by the
direct union of the acid with the base. It crystallizes perfectly in
long transparent needles, which are deliquescent and soluble in
alcohol.

Oxichlorate of Ammonia.—This salt is neutral ; but like ammoniacal
salts in general it is rendered acid by evaporation ; it crystallizes in
very fine transparent rectangular prisms, bevelled at the extremities.
It is soluble in five times its weight of water, and slightly so in alco-
hol. If concentrated oxichloric acid be poured into a strong solution
of this salt, a precipitate is formed which might be supposed to be a
supersalt ; but it is neutral, the acid having seized a portion of the
water which held the salt in solution.

Oxichlorate of Zinc——Obtained by the double decomposition of
zinc and oxichlorate of barytes,—it crystallizes in prismatic groups :
it is soluble in alcohol, and is deliquescent.

Oxichlorate of Manganese.—Oxichloric acid does not act upon
peroxide of manganese. The oxichlorate of the protoxide is obtained
by the double decomposition of oxichlorate of barytes and protosul-
phate of manganese. It crystallizes in long needles, is very deli-
quescent, and is soluble in alcohol.

Oxichlorate of Iron.—Prepared by the mutual decomposition of
oxichlorate of barytes and protosulphate of iron : it crystallizes in
long colourless needles, which remain long exposed to the air without
alteration, but eventually they undergo a change analogous to that of
the protosulphate of iron. By evaporation a portion is converted
into peroxichlorate, some oxide being precipitated ; it hardly melts
upon red hot coals.

Oxichlorate of Copper.—Prepared by heating together peroxide
of copper and oxichloric acid. By evaporation in a stove it gives
bulky blue crystals which have no well determined form, This salt
reddens litmus, deliquesces, and is soluble in alcohol. Paper im-
pregnated with the aqueous solution and dried, fulminates vpon
burning coals with jets of fire of a very fine blue ; when it burns with
flame it is green.

Oxichlorate of Lead.—Prepared by heating protoxide of lead in
water and oxichloric acid ; it crystallizes in small prisms united intoa
mass ; is soluble in about its own ee of water, does not deliquesce ;

3E2 its

396 Intelligence and Miscellaneous Articles.

its taste is slightly sweet and very acerb ; very astringent, and much
more so than acetate of lead.

Protoxichlorate of Mercury.—Dissolve fresh precipitated protoxide
in the acid: by evaporation, small masses of prismatic crystals are
obtained radiating from a common centre; it is not deliquescent ;
precipitated black by ammonia.

Peroxichlorate of Mercury.—Heat the peroxide in fthe facid: it
reddens litmus paper whatever may have been the excess of peroxide
employed. The filtered liquor strongly concentrated and put into a
stove of 88° Fahr. gave very distinct colourless transparent crystals,
having the form of right prisms which are so low as to be tabular ;—
at other times, and probably dependent upon the degree of concen-
tration, it gave long confused prismatic crystals ; but they both ex-
isted only for a short time. They dissolved in the air even in the
stove. This salt is precipitated of a brick-red by potash, and white
by ammonia. In alcohol it forms a white flocculent precipitate, which
upon aggregating becomes reddish ; it is peroxide of mercury. The
solution after filtration and concentration by evaporation, is precipi-
tated of a reddish black by potash, which indicates a mixture of pro-
toxichlorate and peroxichlorate ; when evaporated in a stove it yields,
in the middle of the uncrystallizable liquor, small slender crystals,
which fulminate on hot coals, and are precipitated black by ammonia.

The crystals of peroxichlorate of mercury might perhaps be pre-
served by puttingthe hot solution, properly concentrated, into a small
bottle, and carefully corking it as soon as the crystals are formed.

Oxichlorate of Silver—Prepared by dissolving the oxide in the
acid. The solution becomes brown by exposure to the light. It did
not crystallize in a stove. When dried it is a white powder, and
when exposed to the air it quickly attracts moisture ; concentrated
alcohol dissolves it; when dry, and strongly heated in a tube, it fuses,
and concretes into a mass on cooling ; a small portion is transformed
into chloride ; it is immediately decomposed at a heat a little below
redness ; paper moistened with the solution, then dried at a gentle
heat, detonates violently when the temperature is raised to about
400° Fahr. ;—this was proved by placing parcels of the impregnated
paper upon mercury heated gradually, with a thermometer placed
in it.

All the oxichlorates fuse more or less vividly upon heated coals ;
they generally assume a prismatic form. All that have been above
described are deliquescent, except the oxichlorate of lead, protoxi-
chlorate of mercury, and the oxichlorate of ammonia. In order to
obtain crystals of the deliquescent oxichlorates readily, they must be
dried, dissolved in strong alcohol, and after filtration evaporated in a
stove.

One of the characters which distinguishes the chlorates from the
oxichlorates, is that the first, as well known, become of a deep yellow
colour by the action of concentrated sulphuric or muriatic acid, while
the oxichlorates submitted to the same test remain colourless.— Ann.
de Chim, et de Phys. Mars 1831.

LUNAR

Meteorological Observations for September 1831.

397

LUNAR OCCULTATIONS FOR NOVEMBER.

Occultations of Planets and Jjixed Stars by the Moon, in November
1831. Computed for Greenwich, by Taomas HENDERSON, Esq. ;
and circulated by the Astronomical Society.

———

Stars’

1831.| Names,

Nov. 8 2 Sagittarii
|16 Sagittarii

12 45 Capricor.
1633 Ceti
21/E? Orionis,.
23.2 Cancri.....
24/*° Cancri...

25 Regulus....
26\Saturn......| ...
aa Virginis .

SHAHDD | Magnitude.

3 Immersions.

Ss

Oo

36 Angle from

& Z \Sidereal| Mean ; |Sidereal
a time. |solartime|¢}| 8 | time.
Z ae| S

bePm| hime oa Dy a

2098] 20 40 5 31 66| 89/21 49
2099}21 5 5 57 | 164} 190/21 28
2576] 1 20 9 54} 95) 127|Under
125} 3 8] 11 27 | 160) 184 3 56
777| 418] 1217] 62] 34] 517
998} 0-58 8 50 58} 21] 1 43
1122) 3 8] 10 56 9/329) 3 23
1209| Under Jhorizon | ...| ...|*2 54
-- | 8 55] 16 33} 40] 15}10 3
1551] Under jhorizon | ...| ...| 8 21

Emersions.

Angle from

Mean |- .
solar time. F zg
Z, Pe

6 19 | 200
horizon.| *...
12 15 | 250
13 16 | 310
9 35 | 298
WAT 337
10 37 | 254
17 Al | 272
15 48 | 220

SSS

* At emersion, ) and star rising above horizon.

METEOROLOGICAL OBSERVATIONS FOR SEPTEMBER 1831.
Gosport :—Numerical Results for the Month.

Barom. Max. 30-302. Sept.16. Wind N.E.—Min. 29-295. Sept.30. WindS.E.
Range of the mercury 1-007.

Mean barometrical pressure for the month

Spaces described by the rising and falling of the mercury...
Greatest variation in 24 hours 0:316.—Number of changes 13.

Therm. Max. 71°. Sept. 5. Wind S.W.—Min. 45°. Sept.2. Wind N.W.
Range 26°.—Mean temp. of exter. air 59°16. For 31 days with © innp60-05
Max. var. in 24 hours 19°-00.— Mean temp. of spring-water at 8 A.M. 54-01

Greatest humidity of the atmosphere, in the evening of the 27th...... 96°
Greatest dryness of the atmosphere, in the afternoon of the 3rd...... 48-0
SBME VOMEIIOER, aavor er denis cacrs cells cates nets access2telerceicheanacebaes 48-0
Mean at 2 P.M. 62°-6.—Mean at 8 A.M. 70°3.— Mean at 8 P.M. 77:8

of three observations each day at 8, 2, and 8 o’clock ...... meet ides
Evaporation for the month 2-40 inches.
Rain in the pluviameter near the ground 3-711 inches.
Prevailing wind, South-west.

Summary of the Weather.
A clear sky, 3; fine, with various modifications of clouds, 16}; an over-
cast sky without rain, 54; rain, 5.—Total 30 days.
Clouds.
Cirrus, Cirrocumulus, Cirrostratus, Stratus. Cumulus, Cumulostr. Nimbus.
15 2 0 24 23 17

Scale

398 Meteorological Observations for September 1831.

Scale of the prevailing Winds,

Nap BEE, EB. See ase: S.-W. OW sr NEW Days.
3 5} Le Seno Sra 2 63 30 |

General Observations. — The weather this month has been alternately
wet and dry, and the nights were generally warm.

The Ist was a cold day, with a gale from the North, and heavy rain
nearly an inch in depth, which considerably lessened the temperature of
the ground. Distant thunder occurred in the afternoon of the 2nd; but
the night being clear, with a North-west wind, the first hoar frost ap-
peared in the grass fields early in the morning of the 3rd. On the 7th
and 8th, distant thunder occurred, and the lightning was vivid at mid-
night of the latter day. In the evening of the 12th a faint aurora borealis
appeared from half-past 8 till10 P.M. Early in the merning of the 19th
a great number of swallows assembled, and suddenly departed for a warmer
climate: they remained here this year only twenty-two weeks.

There were a few flashes of sheet lightning in the evening of the 26th.
It lightened in the night of the 27th from 7 P.M. till midnight, when a
change of wind to the North-east brought on a thunder-shower. Heavy
showers of rain and hail in the afternoon of the 28th were succeeded by
vivid lightning, from 5 till 10 P.M. Strong forked lightning, with thunder
and rain, also occurred in the evening of the 30th from 6 till 9 P.M.

The mean temperature of this month is nearly a degree lower than
the mean of September for many years past.

The atmospheric and meteoric phznomena that have come within our
observations this month, are, eleven meteors, one rainbow, one aurora
borealis, lightning and thunder on five days ; and two gales of wind, namely,
one from the North, the other from the South-east.

REMARKS,

London.—Sept. 1. Very heavy rain. 2. Fine, with showers. _ 3, 4. Fine.
5. Rain in the morning: cloudy. 6. Rain: clear at night. 7. Fine: heavy
rainatnoon: clear. §.Fine. 9.Rain. 10.Cloudy: fine. 11, 12, Over-
cast- 13—16. Foggy in the morning: fine. 17.Fine. 18. Slight haze:
fine. 19,20.Fine. 21.Rain: fine. 22. Fogey: very fine. 23, 24. Fine.
25. Cloudy: rain at night. 26. Rain. 27. Hazy and drizzly: fine.
28. Slight fog: heavy rain and thunder at night. 29. Fine. 30, Cloudy
and warm: at night much thunder and lightning, with heavy rain.

Penzance.—Sept. 1. Rain. 2. Showers: clear. 3.Clear. 4. Rain.
5. Fair: rain. 6.Fair: showers. 7, 8.Showers. 9,10,Clear. 11. Fair:
rain. 12. Misty: fair. 13.Fair: misty. 14. Misty: fair. 15. Clear.
16.Fair. 17.Clear. 18.Clear: fair. 19.Showers. 20,Rain. 21.Clear:
ashower. 22,23. Clear. 24. Fair. 25.Misty rain. 26, 27. Misty.
28. Fair. 29. Fair: showers. 30. Rain.

Boston.—Sept. 1. Cloudy: rain a.m.and p.m. 2 Cloudy. 3, 4. Fine.
5. Cloudy: rain p.m, 6.Rain. 7,8, Fine: rainp.m. 9. Cloudy: rain a.,
10. Fine. 11. Cloudy: rain early a.m. 12—17. Fine, 18. Foggy.
19. Cloudy. 20,Fine. 21.Cloudy. 22.Fine. 23. Fine: rain at night.
24.Fine, 25.Fine: rain at night. 26.Fine. 27. Cloudy: lightning at
night. 28. Cloudy: rain, with thunder and lightning p.m. 29. Rain.
30, Cloudy.

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THE

PHILOSOPHICAL MAGAZINE

AND

ANNALS OF PHILOSOPHY.

—>>——_

[NEW SERIES. ]

DECEMBER 1831.

LI. On Isomorphism. In Reply to Mr. Brooke. By Professor
WHEWELL, of Cambridge *.
[X the Phil. Mag. and Annals for September last, appeared
some observations * on Isomorphism,” by Mr. Brooke, in
which a very unfavourable opinion was expressed of the doc-
trine so designated, and of its probable effect on the pro-
gress of mineralogical chemistry. Everything on this subject,
which comes from a gentleman of such exact acquaintance
with minerals as Mr. Brooke possesses, is well deserving no-
tice; and the high claims which have been set up in favour
of the theoretical and practical consequences of the doctrine
in question make it very desirable to ascertain distinctly how
far its pretensions are well founded. I am one of those who
look to it for the solution of many difficulties in mineralogy,
hitherto insurmountable, and who expect that it will lead us
to the true line of junction between chemistry and crystallo-
graphy. I shall be glad, therefore, to state my views of the
evidence on which the doctrine of isomorphism rests, and of
the validity of its proof as compared with that of the theory
which Mr. Brooke opposes to it. I will begin with this last.

1. On the Theory of essential Ingredients and accidental Mixture.

The old theory of the constitution of minerals, to which
Mr. Brooke seems inclined to adhere in opposition to the
doctrine of isomorphism, is, that each mineralogical species
consists of certain parts which are essential; and that the
varieties of composition which we find in actual specimens
arise from the mixture of extraneous substances with these
fundamental elements. Thus Mr. Brooke supposes, at least

* Communicated by the Author.
N.S. Vol. 10. No. 60, Dec. 1831. 3F

4.02 Prof. Whewell on Isomorphism,

as an illustration, ‘‘ that amphibole consists essentially of a
single atom of trisilicate of lime, and that all else which may
be discovered by analysis is accidental mixture.”

The difficulties of this theory appear to me to be absolutely
unconquerable; and if such were the best conjecture we could
make concerning the constitution of our mineral specimens,
we should be compelled, I think, to despair of ever attaining
any distinct or consistent knowledge of them. For if we take
any table of the analyses of amphibole, for instance that in
Leonhard’s Handbuch, we find, besides the lime and silica,
which Mr. Brooke supposes to be essential, a proportion of
magnesia varying from 2 to 25 per cent., protoxide of iron
from 0 to 20 per cent., alumina from 0 to 26 per cent. and
various other ingredients. The smallness of the amount of
these ingredients in some cases, shows that, on any hypothesis
which looks to essential elements, they are not essential;
while the largeness of their amount in other cases shows that
we can acquire no useful or applicable knowledge of the com-
position of minerals by taking up a view in which they go for
nothing.

If we are to neglect 25 per cent. of magnesia or of alumina
in some specimens of amphibole as accidental mixture, by
what right do we take account of the lime as essential, which
in no case amounts to more than 143 per cent.? The che-
mical constitution of a mineral according to such a view must
be a matter of mere assertion; for it not only does not ap-
proximately represent all the ‘good analyses (which is what it
ought to do), but it does not represent any one, within any rea-
sonable limits. It does not represent the analyses any better
than a dozen other suppositions would do taken at random.
It appears to be, on this theory, a matter of arbitrary assump-
tion which part of the analysis is to be supposed essential
and which accidental: and if we could not find any better
mode of considering our analyses, I cannot conceive what
reason there could be for ever analysing a mineral at all. In
interpreting the result, we should always have the difficulty
which Dr. Johnson complained of with regard to an inaccurate
narrator ;—it is of no use to be content with believing half of
what he says, for we do not know which half.

In some cases we may go further, and show that there
cannot be any essential composition, common to all the speci-
mens of the same species. What are the essential ingredients
of garnet? If we again turn to Leonhard’s table, we find
silica indeed common to all the analyses, but not one single
ingredient besides. Alumina, lime, protoxide of iron, per-
oxide of iron, protoxide of manganese, are the most common

of

in Reply to Mr. Brooke. 4.03

of the other ingredients; but there is not one of these which
is not, in more than one case, either absent, or present in very
small quantity. Shall we say then that garnet consists essen-
tially of silica, and that the other substances are accidental ?
that it is thus chemically identical with quartz? This appears
too absurd to be thought of; and yet the doctrine of essential
composition with accidental mixture appears to leave us no
other alternative*.

A case often quoted by the advocates of accidental mixture
is the Fontainbleau spar, and this Mr. Brooke adduces. This
instance has always appeared to me utterly irrelevant. ‘The
carbonate of lime is here crystallized among the previously
existing particles of sand; so that these are imbedded in it
like plums ina pudding. There is no difficulty in such a case,
any more than when any one mineral is crystallized about
splinters or needles of another ;—a very common occurrence.
But who would consider these splinters or needles as belong-
ing to the surrounding crystals? In the Fontainbleau spar,
no one doubts that the carbonate of lime gives the crystalline
character, and that the quartz is caught up in it in grains.
The slightest touch of acid, or scratch with the penknife,
proves this. It is the easiest thing in the world to show that
this is not a homogeneous or simple mineral: the question is
about such as are homogeneous.

Mr. Brooke would perhaps reply to this, that the Fontain-
bleau spar is a palpable mixture, and that other minerals may
be impalpable mixtures: that they may appear to be homo-
geneous when they are not really so: and that there may be
a gradual transition from mixtures obvious to the eye, like
the Fontainbleau spar, to mixtures which cannot be detected
by any physical character, and are discoverable only by che-
mical analysis.

To this I reply, that if we really cannot tell whether a spe-
cimen be approximately a simple mineral, I do not see what
the use can be of analysing it at all. But the way to decide this
point, is to take minerals which possess the obvious qualities
which may be expected to characterize simple minerals; as
transparency, smooth surfaces, apparently uniform structure,
bright and uninterrupted cleavage extending to the smallest
fragments: all which properties the Fontainbleau spar wants.
And if we do take such cases, we neither find ourselves driven
to specimens manifestly very impure; nor do we find by che-
mical examination, large and irregular accidental mixtures.
Who ever detected, in apparently pure quartz, 10 or even 5 per
cent. of extraneous mixture? Who ever discovered in pellucid

* See our present Number, p. 424.—Kpir.
3F2 calc-

4.04 Prof. Whewell on Lsomorphism,

calc-spar any considerable per centage of silica? If we wish
to know the chemical constitution of minerais, we must take
those which are apparently simple, pure, and of determinate
character. If we take those which are plainly impure, mixed,
and indefinite, we are not to be surprised if we find the che-
mical composition also perplexed, variable, and anomalous.
What can we learn by looking, in the first instance, to cases
which we know to be exceptions to all rule, and which no
theory pretends, or can be expected, to include?

The fact which has hitherto so perplexed mineralogists is,
not that zmpure specimens are of anomalous composition ; but
that specimens, apparently pure, homogeneous, and well cry-
stallized, vary in their ingredients in an unaccountable man-
ner: and it is this variation which the doctrine of isomorphism
undertakes to reduce to laws; so that the analyses of all well
selected specimens of the same species shall, within reasonable
narrow limits, agree with the theoretical constitution.

If this theory do not teach us the nature of mineral species,
it at least promises fairer than that of accidental mixture. If
we learn little by comparing our analyses with a standard with
which we conceive them to agree (the isomorphous composition
of the species) we shall learn still less by comparing them with
an assumed standard (the essential ingredients) from which
it is allowed that they may differ widely and by an unknown
quantity. If the half of our specimen may be something dif-
ferent from what it seems, it does not appear what hope we
can have of connecting what seems with what zs in minerals.
If extraneous substances to the amount of 50, 60, or 70 per
cent. may be “‘ cemented together and cased up” in the pure
mineral, without our senses detecting the want of simplicity,
how can we ever distinguish between the case and its contents?

I shall suppose then that when we analyse a well-crystal-
lized, well-characterized mineral, the analysis gives us an
approximation to a chemical constitution belonging to the
species. If this be not so, and if we do not get an approxi-
mation this way, it appears pretty clear that we shall not
obtain such information in any other manner. Any theory
which, like that of accidental mixture, supposes that this may
be no approximation at all, not only disables us from inferring
anything from one analysis, but makes any possible conclu-
sion from any number of analyses, entirely arbitrary, conjec-
tural, and precarious in the first place; and in the next, utterly
inapplicable to any new instance: while in some species, as
we have mentioned with regard to garnet, we can absolutely
prove a negative against that theory, and show that no one
possible chemical constitution can answer to the various re-
sults of analysis, even allowing admixture to any extent.

Il. On

in Reply to Mr. Brooke. 405

Il. On the Evidence of the Doctrine of Isomorphism.

It has already been said that analyses of the same mineral
often give results so widely different that it is hopeless to at-
tempt to discover in them the same chemical compound of
the same ingredients. This being so, we find that a law
nevertheless does prevail in the analyses of the same species,
connecting them together in a definite and certain manner,
and bringing them under a common formula. This law is
given by the doctrine of isomorphism. ‘The evidence of the
doctrine must depend upon the accuracy with which it repre-
sents the facts; and that the reader may judge of this, I will
take the analyses of eight varieties of garnet, given by Leon-
hard in his account of that species (Handbuch, p. 489). No-
thing can apparently at first sight be more anomalous than
these analyses. The alumina varies from 0 to 22 per cent., the
lime from 0 to 34, the magnesia from 0 to 13, the protoxide
of iron from 0 to 34, the protoxide of manganese from 0 to 7.
If we can find any law which approximately includes these
eight analyses, we shall have strong reason to believe that it
has some foundation in nature.

The following is the constitution of each of the eight speci-

mens, expressed in atoms of the ingredients, and re-
duced to such a scale that the atoms of silica are 4.*

Ingredients| S | A | Fes|Fe |Mn| C | M]| K

iW ap Ag 159 Sa

woe ons 98
Z 11} ose "22| 2°74 | se. |p. cent.
"30 | ee "05 | 2°88 | oe. | Zea
coe °59| °39| °51.|.1°43 |p. cent.

PLL PP PPS

If

* T have in this paper used the notation which I have elsewhere recom-
mended (Journal of the Royal Institution, No. 111). _In this, S represents
silica, A alumina, C lime, M magnesia, K potassa, Fe and Fes the prot-
oxide and peroxide of iron, in which the proportions of oxygen are as
2:3; Mn the protoxide of manganese; as, arsenic, s sulphur, c’ carbonic
acid. I have used the atomic numbers of Berzelius.

In the Phil. Mag. and Annals for August, Mr. Prideaux has dissented from
some of the views concerning chemical notation to which I have just ag Reir

wi

4.06 Prof. Whewell on Isomorphism,

If now in the analyses thus expressed, we add together the
numbers in the columns A and Fes, and also those in the co-
lumns Fe, Mn, C, M, we have certain numbers which we
must compare with each other, as follows:

S | A,Fes Fe, Mn, C, M.
(1) 4 | 1:82 2°68
(2) 4 | 1:67 2°55
(3) 4 | 1°86 2°65
(4) 4 | 215 2°74:
(5) 4 | 2-02 3°17
(6) 4 | 211 2:96
(7) 4 | 2°14 2°91
(8) | 4 | 1:97 2°92

Now in these columns the approximate equality of the
numbers in each column is remarkable. None of those in the
second column differ much from 2; none of those in the third
column much from 3; the first column being invariably 4.
We have a degree of resemblance altogether different from
what appeared in the former table. And this becomes stronger
when we notice, that in all the cases the number in the third
column is very nearly one and a half times that in the second,
and that this proportion obtains even where the numbers them-
selves differ from the average, as in (2). We may observe that
in this analysis (2), which is much the furthest from the mean,
we have only to suppose an excess of 7 per cent. of silica,
in order to make it agree with the rest; and that in this case
there must be some inaccuracy in the analysis, since the pro-
portions of the separate ingredients amount to 102 instead
of 100. Jn (4), where the second column is too large, and the
third too small, we are Jed to ask, whether it is possible that
in the analysis any portion of Fe has been converted into Fes:
the probability of such an inaccuracy must be left to chemists
to determine.

But even without making any allowances, I think the agree-
ment of the above numbers is as close as we could expect,

I will leave the matter to be decided by those who may attend to it.
I shall use the notation which I have explained, because it is the only one
which will answer my purpose, as well as the only one which is algebrai-
cally consistent. Those who do not find any inconvenience, or see any
incongruity, in that of Berzelius, have no reason for relinquishing it. The
relative advantages of the two will be discovered by any one who has to
work with them: and there would be little use in a further discussion of
these on general principles.

and

in Reply to Mr. Brooke. 407

and sufficient to justify us in considering 2 and 3 as the stand-
ard values of the second and third columns, from which
values the deviations are comparatively inconsiderable.

It appears then that all the above discordant analyses are
nearly represented, and most of them very nearly, by this
law:—that the atoms of the ingredient S, those of A and
Fes taken together, and those of Fe, Mn, C and M, taken
together, are respectively as the numbers 4, 2, 3. If we put
this law into a formula, according to the notation explained
elsewhere, it will stand thus:

Garnet = 4S + 2 A, Fes + 3 Fe, Mn, C, M;
which may also be put in this form,
2(S + A, Fes) + 2S + 3Fe, Mn, C, M.
Or this, 2(S + A) + 28 + 3C: |
where, in the latter formula, it is understood that a portion
of A may be replaced by Fes, and a portion of C by M, Mn,
or Fe.

Since we can include the above analyses under a simple
arithmetical law by supposing such replacements, while we
can exhibit no such law without this supposition, this example
appears to prove the usefulness of the doctrine that ingre-
dients do thus replace each other; and this is the doctrine of
isomorphism. Such is the kind of evidence on which the
establishment of this doctrine must rest 3 and its certainty
will depend on the exactness with which it will thus reduce
to a common formula a number of analyses of minerals, agree-
ing in crystallographicai and physical character. The above
case is taken unfavourably for the doctrine of isomorphism ;
for if several different chemical formulze ever meet under one
crystalline form, this is perhaps most likely to occur in
crystals of the tessular system, like garnet. It has however,
I think, been shown, that in the case thus taken, the furmula
includes all the analyses, at least within 4 or 5 per cent. ;
while the doctrine of essential constitution is absolutely in-
applicable, inasmuch as silica is the only ingredient common
to all the cases,

A similar examination of a number of analyses of amphi-
bole, with a similar result, is given by Bonsdorf in the Ann,
de Chim. tom. xx., and a similar discussion of pyroxene, by
Rose, in the Ann. de Chim. tom. xxi. Undoubtedly in various
other minerals the true constitution remains still to be dis-
covered, and can be obtained only by the laborious process
of making or collecting many good analyses of the mineral,
well ascertained and pure, and then comparing these in a
manner somewhat similar to that employed above, so as to

discover

408 Prof. Whewell on Isomorphism,

discover the proper formula. This labour has, as yet, been
executed for a few minerals only; so that there remains still
abundant occupation of this kind for the mineralogist, and it
can hardly be doubted, that a clearer insight into the constitu-
tion of crystalline substances will reward such researches, if
diligently pursued. But the above instances, in which, in mi-
nerals of the most complex and apparently confused analysis,
order has been detected by the application of the doctrine of
isomorphism, appear to be sufficient to assure us that that
doctrine has a foundation in nature.

If there be any instances in which the analyses do not con-
form to the formula proposed, as Mr. Brooke asserts to be
the case with regard to amphibole compared with Beudant’s
formulz, there can be no doubt that we must allow either that
the formula is wrong, or the mineral wrongly named, wrongly
analysed, or impure. The isomorphous view of the constitu-
tion of bodies has not, nor can it have, any authority beyond
what it derives from its agreement with facts. The superiority
of this view over that of accidental mixture, arises from its
appearing that the latter gives no approximation at all to
many of the analyses; while the former has given, in the cases
which have been most carefully examined, a very close agree-
ment, under very trying circumstances.

III. On the Principles of the Doctrine of Isomorphism.

Besides Mr. Brooke’s objections to the doctrine of isomor-
phism as not supported by sufficient evidence, he has put for-
ward several objections founded upon theoretical views, which
I shall very briefly touch upon.

In p. 164, he says: ‘ If soda and lime are isomorphous in
relation to 1 or 2 or 3 atoms of silex, there is no obvious
reason why all the other elements that are deemed isomor-
phous in relation to 1 atom should not be so equally in rela-
tion to 2 or 3 atoms,” &c. Mr. Brooke here and in other
cases appears to assume, that if any two elements 2 and y be
isomorphous in one case, they must be so in all: and this be-
cause there is no obvious reason why it should be otherwise.
I confess this appears to me a hazardous mode of reasoning
in such matters. Whether the fact is so or not, must be de-
termined by analyses, and perhaps is hardly yet decided.
The elements which I have denoted by C, M, Fe, Mn, which
appear to be zsomorphous in siliceous minerals, are, it would
seem, plesiomorphous when combined with carbonic acid.

We must, I conceive, hold such ingredients in each mineral
species to be isomorphous, as appear, from analyses, to He

each

in Reply to Mr. Brooke. 409

each other in that species. The general laws of isomorphous
elements are as yet imperfectly understood; and when we
have but one analysis, it must often be difficult or impossible
to decide whether any two ingredients are in definite propor-
tions, or in isomorphous or plesiomorphous relation.

There are many, therefore, of the general arguments em-
ployed by Mr. Brooke which involve reasonings unauthorized
by anything yet established as part of the doctrine of isomor-
phism.

IV. On Plesiomorphous Groups.

We find in many cases minerals which, agreeing in the
form of their chemical formula, and differing in one or more
of their elements, agree also in their system of crystallization,
but differ slightly in their angles and in their physical pro-
perties. Thus carbonate of lime, of iron, of magnesia,
(C+2c!, Fe + 2c’, M + 2c’,) and mixtures of these, all belong
to the rhombohedral system, and have a certain approximate
agreement of hardness, scratch, lustre, cleavage, &c. which
gives them a general resemblance; while their angles vary
from 105° 5’ to 107° 40!, according to the ingredients. Such
minerals have been termed plesiomorphous; and it is evi-
dent, as Mr. Brooke allows, that if we can range minerals
into such groups, we shall have made an important Step
in mineralogy. ‘ If,” he says, * the class of primary forms
can be indicated with certainty by the chemical composition
of a crystallized body, a benefit will so far have been conferred
on science.” Several such groups appear to have been already
detected: thus, besides the rhombohedral group of the form
R + 2c! already noticed, we have the carbonates of baryta,
strontia, lead, and lime (arragonite), which are prismatic; the
sulphates of the same bases, which are also prismatic; and
we have a similar group in the various species into which
mineralogists have subdivided the siliceous minerals formerly
included under the name felspar. Mr. Miller has suggested
the possibility of another group, containing the silicates of
zine, of iron (yenite), of magnesia and iron (peridot) (Camb.
Trans. vol. iii. p. 419). A circumstance which gives additional
importance to these groups is, that besides the agreement in
the system of crystallization, and the close approximation of
their angles, they are always found to possess several other
physical properties in common, or with slight differences.

M. Beudant has asserted a proposition concerning the
dependance of the angle on the chemical constitution in these
groups, which is probably not true; as Mr. Brooke has very
satisfactorily shown. He has maintained, that the angle of

N.S. Vol. 10. No. 60. Dec. 1831. 3G C+ 2c!

410 Prof. Whewell on Isomorphism,

C + 2c! being 105° 5', and that of M + 2c! being 107° 25/,
the angle of any mineral of the kind C, M + 2c’, will be in-
termediate between the two angles, exactly in proportion to
the mixture of C and M in its composition. Mr. Brooke
has pointed out that this doctrine is not reconcilable with the
measured angle and ascertained composition of Breiinnerite.
Indeed it does not appear that M. Beudant has attempted to
establish his law by a series of measures and analyses, and it
certainly cannot be established in any other way. It would
be highly interesting and important to mineralogy to deter-
mine the rule according to which the alteration of the ingre-
dients affects the angle of the crystal; but it is not likely that
this will be done by assuming the first arbitrary conjecture
as the true law of nature.

It is possible that some of the groups held to be isomor-
phous may be plesiomorphous only; and that more exact
measurements may detect differences in angles hitherto sup-
posed to be equal. This discovery would by no means di-
minish the importance of the study of those substitutions of
ingredients by which resembling minerals are related; and
this study is undoubtedly one on which the progress of mi-
neralogy will much depend.

V. On Dimorphous Substances.

It is well known that certain substances exhibit the curious
phenomenon of two different fundamental crystalline forms,
without our being able to detect any difference in the che-
mical constitution of the bodies. Thus C + 2c! appearsas a
rhombohedron in calc-spar, and asa prism in arragonite.
Sulphur is either a right or an oblique prism *. Such dimor-
phous substances certainly offer a difficulty in any attempt to
connect the crystalline form with the chemical constitution ;
but they present no peculiar difficulty to the theory of isomor-
phous or plesiomorphous substitution. The theory of essential
ingredients is at least as much embarrassed by these cases.
If all that is essential to rhombohedral calc-spar be a certain
proportion of lime and carbonic acid ;—if this essential com-
position can impress the character of such calc-spar on 50 per
cent. of silica;—how is it that sometimes, when there is not
1 or + per cent. of foreign admixture, we have quite a different
crystalline form, as in arragonite? Certainly the theory of ac-
cidental mixture has here no superiority; while that of iso-
morphism does on the other hand fall in exactly with the fact,

* From Mr. Brooke’s observations (Ann. Phil. Dec. 1823) it appears to
follow that sulphate of nickel is dimorphous, crystallizing both in right
rhombic prisms and in square prisms, h

that

in Reply to Mr. Brooke. 411

that in some specimens of arragonite a portion of strontia enters
into the composition of the mineral; which is what we might
expect, carbonate of strontia having a plesiomorphous relation
to arragonite.

In other cases, such as those adduced by Mr. Brooke, of
paranthine and sodalite; of eudialyte, zircon, and olivine; it is
very far from being clearly established, as yet, that the che-
mical formulz of these groups can be made respectively iden-
tical, even by the substitution of isomorphous elements; and
it certainly has not yet been proved that in these cases the
elements are isomorphous. If there be really dimorphous
minerals of this kind, the observations of the last paragraph
may be applied to them: at present we do not appear to pos-
sess a sufficient number of good analyses of these species, to be
able to determine how far they are examples of the theory.
But certainly the theory of accidental mixture cannot possibly
explain any difficulties of this kind, which the theory of isomor-
phism will not explain at least as well.

I am therefore surprised that Mr. Brooke should haye
brought forwards such cases as objections to the isomorphous
theory. But I am still more surprised that he should have
brought forwards as objections the differences which occur in
other cases, where the very essence of the theory requires that
there should be a difference, and when the theory could not
stand a moment if there were none. “ Arsenic,” he says,
“combines with sulphur in two different proportions, and
producing different primary forms. Hence the proportion of
a common element, and therefore an isomorphous one, occa-
sions a change, even in the system of crystallization.” No
doubt the change of the proportion of an element occasions
a change in the crystallization: we should have little chance
of finding any connection between the elements and the cry-
stallization if it were not so: as + 2s (realgar) and as + 3s
(orpiment) have different chemical formule, and accordingly
we find they have a different system of crystallization. How
Mr. Brooke conceives that the theory of isomorphism can
identify these two compounds, I cannot understand. If, when
he says, “a common element, and therefore an isomorphous
one,” he means that ¢wo atoms of an element are isomorphous
with éhree, he certainly supposes what no advocate of isomor-
phism ever dreamt of.

In like manner I cannot see how the isomorphous theory
offers any ground for the expectation, of which he speaks,
that the sulphuret of silver, the sulphuret of copper, and the
sulphuret of bismuth should present similar forms. For it is
not asserted, so far as I am aware, either that the number of

8G? atoms

412 Unequal Refrangibility of Light on the undulatory Theory.

atoms of sulphur is the same in each of these minerals, or that
these metals can ever replace each other as isomorphous ingre-
dients ; so that all ground of comparison vanishes.

I will conclude with noticing the obligation which the doc-
trine of isomorphous and plesiomorphous groups, as well as
other parts of mineralogy, owes to Mr. Brooke himself. Thus,
among other instances, (Ann. Phil. Aug. 1823,) he has re-
marked the near agreement in form, of sulphate of iron and
sulphate of cobalt: also(Ann. Phil. Dec. 1823) that of the sul-
phate of nickel and the sulphate of zinc ; and (Ann. Phil. Jan.
1824) the exact agreement of nitrate of lead and nitrate of
baryta.

Trinity College, Cambridge, Nov. 7, 1831. W. W.

LIL. Unequal Refrangibility of Light on the undulatory
Theory. By A CorrEsPoNDENT.

6 Devan undulatory theory of light has now been shown to

apply with such distinguished:success to every pheeno-
menon, even the most recondite and complicated which the
researches of physical optics have disclosed, that no other
doubt can remain on the mind of the competent examiner of
its doctrines than that which results from the single exception
to its universal application ; viz. the explanation of the phz-
nomenon of the unequal refrangibility of the different rays of
light.

In regard to this apparent exception several suggestions
have been made possessing high claims to attention. With-
out discussing their merit, it may be permitted to the writer
of these lines to propose another which seems to him more
free from objections than many of those which have pre-
ceded it.

It will be admitted that the same difficulty which attaches
to the explanation of the modifications which the undulations
undergo within the refracting medium, applies to the concep-
tion of their condition in the medium out of which they enter
it. If we have only one homogeneous medium, it seems im-
possible to conceive more than one kind of undulation going
on at the same time in it; the elasticity being an essentially
constant element. If we could by any possibility conceive dif-
ferent elasticities coexisting, and by consequence, vibrations
impressed with different velocities giving rise to undulations
of different lengths at the same time, these would of course be
unequally retarded on entering the denser medium, and un-~
equal refraction would take place.

The suggestion now offered consists in this,—that such a
coexistence

Rey. R. Murphy on the Symmetrical Functions of Roots. 413

coexistence of unequal elasticities is not only possible, but must
be the case; for if the ether be an elastic fluid uniformly dif+
fused through space absolutely devoid of other matter, it fol-
lows that wherever it penetrates a space filled with any me-
dium, such as air, it must necessarily be attracted round each
particle of air, and form spheres of a density increasing towards
their centres. Amongst an infinite number of such spheres
uniformly diffused, a succession of vibrations communicated in
a given direction, will of course give rise to vibrations propa-
gated with various velocities, according to the particular elasti-
city of different parts of the disseminated medium: thus we
shall have a number of coexistent vibrations producing un-
dulations of different lengths which, when they are incident
upon a new medium, will cause a deviation in position pro-
portional to the unequal lengths of their undulations, accord-
ing to the well known and established explanation of the
general law of simple refraction as expressed by the undula-

tory theory.
November Ist, 1831.

LIII. On the Symmetrical Functions of a specified Number of
the Roots of an Equation. By the Rev. R. Murpuy, Fellow
of Caius Coll. and of the Camb. Phil. Soc.

To the Editors of the Philosophical Magazine and Annals.
Gentlemen,

[X a paper published in the last Number of the Transactions
of the Cambridge Philosophical Society, I have given a
few simple rules relative to the solution of algebraical equa-
tions, with their demonstrations. The sum of any specified
number of the roots taken in order from the least, upwards,
and the sum of any given function of such roots, may be
thence found, for any proposed equation ¢(x) = 0, containing
only positive and integer powers of z. ‘The coefficients of the
different terms of an equation are, as is well known, the sums
of symmetrical functions of al/ the roots; and my present
object is to show a simple method of obtaining the corre-
sponding sums of the symmetrical functions of a specified num-
ber of the roots; and as general investigations relative to a
specified number of the roots are I believe new in analysis,
this paper may not be unacceptable to your mathematical
readers.

Let ct) 5 5 dg seve» tm be the m least roots, taken in order,
of the equation $ («) = 0, and A any arbitrary quantity. ‘Then
by arule given in (§ 3) of the paper above referred to, we get

log

414 Mr. Haworth’s Thirteenth Decade of New Succulent Plants.

log (1+ Aw) + log (1+ Aa) + «+. log (1+ Acm) = coeffi-
—A~A $(x) : eo

Treat log om This coefficient is a func-

tion of A, suppose (A). Hence (1+ Aa). (1—Ady) sereeeeee

‘ bugis
cient of — in
x

(l+Aa¢@m) = eV) « being the base of Napier’s logarithms.

Let «¥@ be expressed in powers of A, the general term
being w,. A”, and suppose we equate the terms involving like
powers of A, on both sides of the equation; then

First; When p<m, u, is evidently the sum of the products
of the m least roots, taken p and p together.

Secondly; When p = m, u, = the product of the m least
roots.

Thirdly; When p>m, u, is zero,

From the third case, it follows, that in applying this method
we may always reject from (A) all the terms after that which
involves ”.

A process exactly similar will give the combinations p and
p together, of any functions of the m least roots or their con-
tinued product. Iam, Gentlemen, your obedient Servant,

R. Murpuy.

LIV. Decas tridecima Novarum Plantarum Succulentarum ;
Autore A. H. Hawortnu, Soc. Linn. Lond.—Soc. Horticult.
Lond.—Soc. Cas. Nat. Curios. Mosc.—necnon Soc. Reg. Hor-
ticult. Belgic. Socius: &c. Sc.

To the Editors of the Philosophical Magazine and Annals.
Gentlemen,
1) Saal a longer space than usual between my communi-

cations to your valuable Magazine and Annals, I send you
hereunder my thirteenth Decade of New Succulent Plants,
for insertion, if you please, in an early Number of that useful
work.

As heretofore, I have carefuliy stated the native countries of
every species,—detailed, but with due precision, their botani-
cal characters; and not failed to record the rich gardens from
whence I have received them. And to all these particulars
I have added such contrasting and other characters as may
enable the gardener to grow them, the botanical tyro to un-
derstand them, and every able author to appretiate and blend
them with their old affinities in a scientific way.

I remain, Gentlemen, yours, &c.

Chelsea, Aug. 30th, 1831. A. H. Haworrn.
Ord.

Mr. Haworth’s Thirteenth Decade of New Succulent Plants. 415

Ord. Nat. BROMELIACE/, Juss. Gen. Pl. 49.

Genus AcAvE, Linn. Gen. Pl. 582.

univittata. A. (red-edged white-striped): foliis laté lorato-

1.

lanceolatis acuminatis pungentibus, margine rufo acu-
leato-serrato, costa univittata.

Habitat in Mexico. G.H. %.

Ex regio horto Berolinense communicavit amicus
Dom. F. Otto, A.D. 1830.

Obs. Proxima fortassé Ag. angustifolie Nob. at folia
magis patula seu inflexo-concava, erecto-expansa vel
parum recurvantia crassa dura seu loreo-rigida niten-
tia, atro-viridia, costd laté alba, in spina atro-rufa valida
affinium desinente; aculeis marginalibus distantibus
validis adunco-respicientibus atro-rufis, margine ipso
tenuiter cartilagineo etiam atro-rufo; mox albicante
periente : swbtuws (folia) convexa pallida sive parm al-
bicantia (lateribus alté viridibus) lineolis numerosis pa-
rallelis contiguis longis sed deorsum szepius interruptis
atro-viridibus basin versus plus minis evanescentibus.

Juvenem plantam solum habeo, foliis adhuc vix pe-
dalibus 9-10 lineas latis.

Fortassé varictas vittata et lineolata preesingularis
plantz originalis quedam absque vitta vel lineolis;
nihilominus proprize species.

Ord. Nat. TULIPACE/E, Kunth Synops. 1. 292.

Genus Yucca Auctorum, et Nob. in Suppl. Pl. Suce. p. 31.

charactere novo ampliori.

Sectio *** INTEGERRIM®: foliis margine integerrimo levi,

caudice 1-10-pedali valido recto. Nob. 1. c.

aletriformis. Y. (The undulate-leaved): foliis capitatis erecto-

recurvis undulatis lorato-attenuatis longé acuminatis
viridibus nitidis levibus, margine ipso cartilagineo al-
bicante integerrimo.

Habitat Capite Bonz Spei, et exindé ad regium hor-
tum Kewensem misit, A.D. 1823, amicus peregrinator
Dom. Bowie; adhuc non floruit in horto, sed ibi pul-
chré viget, Aletrem speciem simulans. G. H. hk.

Obs. Caudex adhuc bipedalis firmus teres diametro
sesquiunciali.

Folia eleganter capitatim collecta (capite longiore
quam in plurimis) et concinné basi imbricata: nunc
in nostro exemplo subbipedalia, 15-16 lineas lata,
sublorea, basin versus crassiora et succulentiora, supra

medium

416 Mr. Haworth’s Thirteenth Decade of New Succulent Plants.

medium vix undulata sed pedetentim prodeuntia in
acumine longo; supra, preecipué basin versus, inflexo-
canaliculata, subtus obtusé carinata, carind supra me-
dium sensim sensimque evanescente.

Ord. Nat. CRASSULACE, DeCand. Prod. v. 3. p. 381.

Tribus 1. CrassutEx, DeCand. Prod. ib.
Genus Sepum Linn. &c.

Sectio AcUTIFOLIA Nod.

subclavatum. S. (green club-leaved): foliis imbricatis, in ramo-
3. rum apicibus rosulas subformantibus subclavatis, tur-
gidis viridibus, apicem versus attenuatis acutis.

Habitat in America Septentrionali.

Rami et ramuli perennes, primo anno 3-4-entales,
stabiles, sed flexo-decumbentes teretes foliorum cicatri-
cibus crebre et transversaliter lineolatim notati, aspe-
riusculi. Folia breviora et obtusiora quam in affinibus
hujus sectionis, sed levia incurva tumida et carnosa;
subtus convexa, supra obsoleté depressiuscula.

Floret nondum in Anglia, sed in Horto Pharmac.
Chelseiano pulchré vigebat A.D. 1830. Species di-
stinctissima, vix ullze valde affinis, sed prope S. Forster7,
Engl. Bot. tab. 1802, locarem pro tempore. H. .

Obs. Under the genus Sedum may appropriately be
noticed some Seda I have long cultivated, and which
it will be a botanical improvement to describe briefly
as follows; for the first three appear to be distinct
species: viz.

Sectio optusiroLia Nob, floribus cymosis.

album. S. (blunt-leaved white) : foliis clavato-ovatis viridibus
teretiusculis glabris, ramis perennibus radicantibus,
junioribus in Jente puberulis.
Sedum album Eng. Bot. t. 1578.
Sedum album y DeCand. Prod. v. 3. p. 406.
Flores valdé cymosi albi.
Habitat insuper muros prope Londinum. H.%.
micranthum. S. (greater blunt-leaved) : foliis clavato-oblongis
viridibus teretiusculis glabris, ramis perennibus radi-
cantibus, junioribus in lente puberulis.
Sedum album 6 micranthum, DeCand. Prod. v. 3.
p. 406.
Habitat prope Gloster. H. /.
Communicavit amicus Rev. Dom. Ellicombe.
Obs. Antecedenti simillimum, at 2-3-plo majus, flo-

ribus numerosioribus minoribus petalis angustioribus.
tereti-

Mr. Haworth’s Thirteenth Decade of New Succulent Plants. 417

teretifolium. S. (slender blunt-leaved) : foliis zequaliter teretius-
culis subelongatis parum depressis viridibus ramisque
subelongatis perennibus radicantibus, omnino glaber-
rimis.

Sedum album «a, DeCand. Prod. 3 p. 406. quod
est S. teretifolium Lam. Fl. Fr. 3. p. 84.

Obs. I have not seen the flowers of this plant, which
was sent to me four years ago, from the Bury Botanic
Garden, as, J think, a Hertfordshire plant, gathered
wild there by the late venerable Sir Thomas Cullum.
Its shoots are more than twice the length of the last,
and its leaves are half as long again, often cylindrical
and more remote, and it is destitute of all pubescence
even when magnified. I suspect it is a maritime plant,
requiring a saline air, and perhaps a saline soil, to
produce its flowers. It bears a greater resemblance
to a Mesembryanthemum than any other Sedum I am
acquainted with.

Habitat prope Hereford? H. }.

With the above Seda, mention may be here, and
appropriately, made, of two remarkable varieties of
Sedum acre, sent from the Bury Botanical Garden at
the same time with the preceding; viz.

acre. S. var. 6 diminutum. multoties minus quam S. acre
Fing. Bot. tab. 839. An Sedum acre B glaciale, De-
Cand. Prod. v. 3. p. 407?

Obs. Valdé repens glomeratum, facie feré Lycopodii
parvi. Lrecti rami steriles unciam alti; florentes, vix
sesquiunciales. Folia magis conferta et minus viridia
quam in §. acre Eng. Bot. tab. 839, in ceteris feré
omnino concordat. Sed caules 2—3-, rarius 4-flori so-
lum, nec 4-8, flori ut in S. acre. H. 2.

Obs. This diminutive plant, my judicious friend
Mr. John Denson, jun. (late Curator of the Bury
Botanical Garden) assures me was gathered wild on
Swaffham Heath, Norfolk; by, I think, Mr. William
Christie, jun. of Clapham; and it may eventually
prove to be a genuine species.

The second variety may be called

acre y elongatum. §. ramis pendulis 7-uncialibus; erectis
4-uncialibus, foliis laxé imbricantibus.

Obs. This var. Mr. Denson mentioned not the origin
of. Its shoots are three times longer than those re-
presented in Zing, Bot. tab. 839, and its leaves are more
patulous and more distant from each other, and it pro-

N.S. Vol. 10. No. 60, Dec. 1831. 38H duces

418 Mr. Haworth’s Thirteenth Decade of New Succulent Plants.

duces flowers less frequently; but it is only a variety.

Hei:
Genus Ecueverta DeCand. l. c.

Herbe mexicane succulentze glauce perennes vel
suffrutescentes, foliis crassis levibus basi solutis, et
feré Sempervivi modo in rosulas laxas expansis; flori-
bus racemosis seu spicatis, vel spicatim paniculatis
coccineis seu luteis, pedunculis brevibus seu brevis-
simis.

* Floribus coccineis.

lurida. E. (The dingy-leaved) subczespitosa: foliis imis lan-

4.

ceolato-cuneatis lividis, superioribus lanceolatis, floribus
racemoso-spicatis.

Habitat in Mexico. G. H. 2.

Communicavit amicus Dom. Otto.

Obs. Herba succulenta perennis sive suffrutex laxé
czespitosa surculis paucis brevibus. Folia paginis le-
vibus glauco-fusca inflexo-concava, et nitentia, si bené
culta; subéws convexa obtusé carinata, margine carti-
lagineo, tenuiter exasperato; apice sepe parum re-
curva acuminulata. Scapz in planta nostra tres do-
drantales vel pedales, teretes et minimé sursum attenu-
ati laeves pallidi seu albicantes, primo terminales, sed
citits 6 progressione plante laterales et basi parum
flexi, mox recti et erecti foliolosi seu bracteati. Bractee
alterne, folio consimiles, gradatim sursim minores,
distantes patulz, vel inter flores recurvule. Omnes
bractee sic leviter scapo adnate, ut citius decidua, e
levissimo tactu, et insuper terram facillimé radicantes,
et (uti folia) in proprias plantas crescentes. Flores
racemosi, seu racemoso-spicati; superiores confertiores ;
aperti horizontales. Pedunculi breves subindé 1-2-
bracteolati. Corolla ut in £. grandifolia Nob. sed magis
coccinea, et certo situ rore glauco cum rubedine viva-
citer violascens.

Ord. Nat. EUPHORBIACE, Juss. Gen. 384.

Genus Tirnymatus Mill., Nob. in Synops. Pl. Succ. p. 137.
uniflorus. T. (American tuberous) tuberosus levis: foliis obo-

5.

vatis subpetiolatis, floribus pedicellatis solitariis in ra-
morum dichotomiis.

Habitat in America Meridionali. St. 2/.

Florebat in caldario regio ditissimo Horto Kewensi
A.D. 1829, mense Julii, ubi descriptionem sequentem
faciebam.

Radix

Mr. Haworth’s Thirteenth Decade of New Succulent Plants. 419

Radix feré ut in 77th. tuberoso Nob. qui est é Capite
Bonz Spei, et satis cognitus. Caules pauculi subsemi-
pedales exigui teretes patentes carnosuli herbacei, in
caldario debiliter decumbentes furcati sive simpliciter
dichotomi, apicibus assurgentibus.

Folia alterna remotiuscula integerrima in petiolos
(in caldario) deorsum attenuata subavenia pallidé vi-
ridia satis tenuia, nihilominus carnosula. Flores
pauci parvi ordinaril inconspicui.

Cetera non examinavi, et post florescentiam per-
fectam solum vidi. Est planta herbacea tuberosa ex-
igua laevis edentula et adhuc non scripta.

Ord. Nat. CACTEAL, DeCand. Prod. ». 3. p. 457.
Tribus primus; seminibus parietalibus.
Subgenus Ecuinocactrus Link et Otto Diss. p. 11.

Cotyledones due basilares (secund. DeCand.). Jn-
florescentia apicem plante versus. <Azis centralis lig-
nosus Cereorum modo.

Obs. Plante multangulares breves carnose epider-
mide duro lzevi tectee suboblonge grossz vel saepissimé
spheroidez ; cost7s spinis validis seepé intertextis crebré
armatis. Subgenus solum Cereo proximum.

Sectio nova Gipzost. Costis gibbere notabili carnoso
subsingulo spinario*, praecipué in junioribus notatis,
inde (costz) superné lobulatim undulate evadunt.

Huc referendi Ech. gibbosus necnon E. nobilis Nob.

subgibbosus. E. (strong-spined gibbous) rotundo-oblongus, in-
6. tertextim valde spinosus; angulis subsexdecim Jobu-
laribus, sinubusque profundis acutis, spinariis distanti-
usculis.

Habitat prope Valparaiso in America Australi, ubi
legit Dom. Brydges, misitque Dom. Tate vico Sloane-
street, qui mecum communicavit mense Junii A.D.

1830. St. hk.
Obs. Planta adhuc nondum floruit apud nos: sim-

* Spinarium in Cacteis est organum corneum induratissimum carne
immersum in quo spine distincté insertee sunt, uti animalium dentes in
maxillam.,

Spinaria foliorum forsan modificationes sunt, et rami, ramuli, flores-
que, necnon subindé folia vera, vel foliola, ex eorum axillis prodeunt.
Nihilominis sguamue@ forsan foliacee exstant in Cereo squamuloso, aliisque
perpaucis ; Poesy fs sediformia vera in numerosis Opuntiis, omnino extra
spinaria. Supradicta squamula Sectionem novam indicant; uti aphylla
Opuntia.

$H2 plex

420 Mr. Haworth’s Thirteenth Decade of New Succulent Plants.

plex est, 5 une. alt. et 3 unc. lat. epidermide leté vi-
ridi, apice depresso umbilicato. Angulz validz spinis
horridis intertextis totam plantam feré tegentibus.
Spinarium sub-16-spinosum lanosum hemisphzericum.
Spine sub-12-13, rect; harum ime feré zquales
setiformes subsemunciales albicantes seu pallida ra-
dianter horizontales: sub-sex swmme subaculeiformes
multoties majores subunciales validiores basi bulbosz
patulz fulvicantes apicibus rufescentibus: harum ulti-
marum (spinarum) una ceteris respectu centralis et
erectus est.

Genus Cereus Mill., Nob.
Sectio GRANDANGULARES, erecti, Nob.

validus. C. (stout quadrangular) tetragonus firmus: apice
7. glauco; lateribus feré planis, vel primo convexius-
culis; ipsis angulis obtusissimis, mediocriter spinosis.

Habitat in America calidiore. St. h.

Obs. Unam plantam nativam in caldario regio horto
Kewense pulchré crescentem solim vidi. Nunc in
quarto anno simplex et subsesquipedalis est, erectus,
basi trigonus, superne tetragonus ; facie et crassitie feré
C. tetragoni Linn. sed affinior forté C. obtuso Nob. ; at
valdé robustior. Spznaria inter se valde distincta,
lana ordinaria densissima centrali brevi; spznzs variis
mediocribus erecto-patulis fulvo-fuscis, apicem versus
seepé fulvicantibus et 3-6-linearibus.

Anite Cereum obtusum Nob. certé locarem.

Obs.— Cereus magnus Nob. in Phil. Mag. Feb. 1830,
p- 109: bis florebat in caldario apud Dom. Rolls, King’s
Road, Chelsea, in annis 1830 et 1831, Augusti mense.

Descriptio :—Flores diurni speciosi solitarii, apicem
versus suberecti dodrantales et feré ut in C. hexagono
parum suaveolentes. Twbus cylindraceus usque ad me-
dium eequali crassitie virescens, et affinium more squa-
mulosus et spinulosus, spinis ibi longioribus graciliori-
bus; supra medium duplo inflatior pallidior, sguamulis
ordinartis calycinis lineari-acuminatis distantibus vi-
ridibus; tunc petalozdeis et petalis etiam ordinariis albis
lorato-lanceolatis acutis, toto mane apertis patulis usque
ad 4 uncias, subius apicem parum graciliter carinulatis.
Stamina numerosissima pallidé sulphurascentia, in or-
dine conferto regulari circulari juxta petala, sed eos
non tangentia, antheris minutis. Stylus ordinarius param

declinatus, altitudine circiter staminum, st7gmatibus 14
radianter

Mr. Haworth’s Thirteenth Decade of New Succulent Plants. 421

radianter recurvulis obtusis subquadrilinearibus ali-
quantillum puberulis. Cetera ordinaria.

Ord. Nat. FICOIDEA, Juss. Gen. 315.
Genus MesEMBRYANTHEMUM Linn. Gen. No. 628.

Sectio PLATYPHYLLA.
++ Foliis planioribus vix undulatis basi cuneatis.

puberulum. M. (white-flowered puberulose): foliis oppositis

8. alternisque obovato-spathulatis inflexo-canaliculatis ca-

rinatis; ramis floriferis, foliorumque marginibus pube-
scentibus: pedunculis subcylindricis erectis.

Obs. A seminibus nativis Capensibus in horto Chel-
seiano ortum A.D. 1829. G. H. ¢.

Radiz annuus fibrosus. Caulis ramosus procumbens;
ramulis erectis subteretibus vel paululum angulosis
crystallino - papulosis ad lucem uti folia calycesque.
Folia et Calyx feré ut in M. papuloso Linn. cui forsan
proximum, a quo differt in pedunculis non reflexis.
Flores feré ut in M. papuloso, pomeridiani semunciales
albi, (pedunculis uncialibus) imprimis apice, extus fla-
veolentes sed mox undique albi, petalis linearibus ob-
tusis. Genitalia flava. Styli 5, apicibus patulis seu
valdé recurvis; st7gmatibus capitularibus, antheras pal-
lidioribus et plerumque superantibus.

Obs. Pone M. papulosum Linn. locarem, cui simil-
limum, sed statura adhuc breviore foliis floribusque,
etc., eadem magnitudine. Calyx 4—5-phyllus, basi
4-5-gonus, foliolis 2—%, foliiformibus, at longé minori-
bus; 2 aliis valdé diminutis et alatim membranaceis.
Cetera nor examinavi.

Sectio nova, StENA. Suffrutices feré minimi, ramis
subinde semipedalibus effusis, folzisque filiformi-
bus, petalis angustissimis vel setaceis pallidissimeé
roseis. Pone sectionem PALLIDIFLORAM locarem,
cum M. debili Nob. in Phil. Mag. pone M. stenum,
cui magis affine quam antiquo M. reptanti.

slenum. M. (The slender): ramis effuso-decumbentibus flexu-

9. osis filiformibus, foliis gracilibus falcato-incurvulis tri-

quetro-teretiusculis mucronatis paucipunctatis glau-
cescentibus, floribus 1—3-natis terminalibus.

Habitat C. B.S. G. H. k.

Obs. Vigebat in regio horto Kewense A.D. 1830 ¢

seminibus nativis a Dom. Bowie missis. Florebat Aug.

1831. Suffrutex tenuis, ramis semipedalibus subcon-

fertis

422 Mr. Haworth’s Thirteenth Decade of New Succulent Plants.

fertis numerosis seepius decumbentibus et effusis, aére
aperto cortice basin versus albicante, medio, rufo-fusco
sive badio, apice purpurascente. Folia 5-9-linearia
lineam lata medio subcompressa, utraque subatte-
nuata glauca seu glaucescentia ad lucem szpits obso-
leté paucipunctata. Pedunculi breves teretes clavati.
Calyx 5-phyllus ordinarius subtuberculatus foliolis
acuminatim mucronulatis. Corolla antemeridiana pal-
lida (M. glomerato major) violaceo-erubescens, petalis
valdé angustatis integris, interioribus pedetentim mi-
noribus tenuioribus pallidioribus s. albis setiformibus
et magis magisque imperfecté antheriferis, et erecto-
collectis usque ad vera sfamina, que petalis breviora
sunt et collecta, antheris pallidé sulphurascentibus.
Styli 5 breves inter stamina reconditi ordinarii.

Obs.—M. debile Nob. (quod affinior M. steno quam
M. reptante) florebat in regio horto Kewense, A.D.
1830, verno tempore. lores terminales perpauci,
minores quam in M. steno, pallidissimé erubescentes
sive albicantes, antemeridiani. Vidi sed non exami-
navi.

' Sectio HISPICAULIA Nob.

Surfureum. M. (branny-twigged) : ramis confertis rectiusculis
10. rigidis furfuraceis, follis cylindricis obtusissimis caly-
cibusque obsoletitis papuloso-crystallinis; floribus par-
vulis numerosis.
Habitat Cap. Bon. Spei, ubi invenit spontaneum
misitque ad regium hortum Kewensem A.D. 1830
amicus Dom. Bowie. G. H. kh.

Obs. Nova species. Suffrutex dumosus dodrantalis
rigidus. Rami seu ramuli recti numerosi patuli et
feré filiformes furfuro at oculo inarmato non valdé
conspicuo tecti. Folia matura in florentibus plantis
aére aperto conferta, 4—9-linearia subpallidé seu sor-
didé virescentia patentia in ramulis numerosis brevis-
simis lateralibus et copiosé florigeris. Flores ramulos
terminantes sepé solitarii, pedunculis brevibus furfu-
raceis absque bractcis propriis. Calyx 5-phylloideus
ordinarius papuloso-crystallinus, foliclis obtusissimis
subzequalibus longitudine. Corolla inter minores, late
rubicunda subsemiuncialis A.M. expansa sub radiis so-
laribus, petalis uniserialibus sublinearibus szepius inte-
gris.

8. Variat, minus: floribus seepé ternatis.

Obs.—M. floribundo Nob. affine, a quo differt statura

subduplo

Mr. Haworth’s Thirteenth Decade of New Succulent Plants. 423

subduplo minore ramis rigidioribus forté confertiori-
bus et rectis vel subrectis (non torquatis ut in M. flori-
bundo) ramulis patulis; foliis forsan minus viridibu s;
at nihilominus pone id locarem.

Obs. Folia summa incipientia szepé obsoleté trigono-
cylindracea, sive supra planiora vel depressa.

Obs. Under this Section of the present Genus it is
appropriate to remark that M. hispidum « & B of
Revis. Pl. Succ. p. 186. are two distinct species, easily
separated by the following characters.

hispidum. M. (hispid-peduncled): foliis cylindricis obtusissimis
calyceque glabro obconico viridibus papuloso-micanti-
bus, staminibus pistillo longioribus, ramis pedunculis-
que hispidis.—M. hispidum a, |. c.

subhispidum. M. (smooth-peduncled): foliis cylindricis obtu-
sissimis calyceque glabro feré obconico subviridibus
papuloso-micantibus, ramis plerumque et pedunculis
omnino depilatis.—M. hispidum B, 1. c.

Obs. Priore elatius, longé minus ramosum,ramis longi-
oribus erectioribus strictioribus, distantioribus gracilio-
ribus et florentibus feré semper denudatis vel aliquan-
tillum furfuraceis. Foléa (uti calyces) minis papuloso-
micantia, et minus intensé viridia. Petala dupld la-
tiora seu minus cuneata, longé pallidiora, costa basi
subindeé albicante, apice altiis emarginata. Stamina
stylos subzequantia, pallidiora breviora minus expansa,
at crassiora, uti anthere itidem pallidiores. Capsule
angulis maturis, longé minus productis, et obtusi-
oribus.

Obs. Professor DeCandolle, in his Prod. v. 3. p.441,
under his M. tuberculatum, cites my M. hispifolium
as synonymous, saying “foliis acutis papulosis molli-
bus” &c.—but my plant in its var. a, has folia valdé
obtusa pilis respicientibus tecta: and in its var. f,
which is twice as large, is rather less obtuse-leaved,
but by no means acute. Can M. DeCandolle’s plant,
therefore, be my M. hispifolium 6? or, are the three
distinct? My £. I have known forty years in Chelsea
Garden; «. only seventeen years.

Obs. 2. Closely allied to this species may appropri-
ately be briefly added, for the first time, an account of
the rare flowers of M. candens, Nob. Revis. Pl. Succ.
186. and of a new variety of it from the Prince of Salm-
Dyck, as follows :

candens.

424 Mr. Brooke’s Additional Remarks on Isomorphism.

candens. M. (white trailing hispid) :

a minus: foliis magis candentibus. Flores (duos solim
vidi) terminales in ramulis lateralibus, solitarii parvi
albi concinni antemeridiano, mox erubescentes, deni-
que leté rubicundi. Czteri ordinarii.

Floret Junii mense. G. H. h.
8 viridius, dupld majus omni parte, foliis viridioribus
floribus (horum 2 solum vidi) albis seu niveis pulchri-
oribus mox erubescentibus, denique alte rubicundis,
antemeridianis.

Floret Septembris mense. G. H. h.

Obs. 3. Rami prostrati hujus speciei ex eorum nodis
valde radicant, uti Fragrarie sarmenti.

LV. Additional Remarks on Isomorphism. By H.J. Brooke, Esq.
ERS. LS. § G.S.*

N the appendix to a work just published by Dr. Daubeny

on the Atomic Theory, some observations are inserted re-

lative to a paper of mine on Isomorphism, inserted in No. 57
of this Journal.

Upon these observations I shall at present only remark,
that they contain two paragraphs upon which I am desirous
of immediately setting my self right with Dr. Daubeny and the
readers of his work.

Dr. Daubeny says, “It seems impossible to apply the (theory
of mixture of foreign matter] to the garnet species, neither has
Mr. Brocke attempted to do so.”

What mineral is it, I should first be disposed to inquire,
that is to be designated by the name of Garnet? It is not
denoted by its crystalline form, for that is common to a
variety of others; and there is no very apparent reason why,
among the substances which, chiefly on account of their si-
milar ‘forms, have been included under the supposed garnet
tribe, there should not be some, which, on account of their
chemical differences, do really constitute distinct species.
To enter, however, upon an investigation of this question
would require a knowledge of the chemical constitution of the
matrices or rocks in which the several varieties have been
found ;—a point upon which scarcely any correct information
can be collected from the published works on the subject.
And probably on reconsideration Dr. Daubeny will be of
opinion, that the garnets are, from the class of forms to which

* Communicated by the Author.
they

Mr. Brooke’s Additional Remarks on Isomorphism. 425

they belong, the last which ought to be adduced as evidence
either of the truth or fallacy of isomorphism.

The second paragraph to which I have alluded is as fol-
lows :—

‘It may be remarked, that in the case of Stilbite which
Mr. Brooke has brought forward as an exception, he has over-
looked the presence in it of 6 atoms of water,—a circumstance
which constitutes a chemical difference between that mineral
and paranthine.”

This however involves an entire misrepresentation of what
I have stated ;—unintentional I have no doubt, and occasioned
by hasty perusal of what I wrote. I did not, as Dr. Daubeny
will perceive on looking again at my paper, raise any question
about the form of Stilbite. I referred to Eudyalite as an ex-
ample in which soda and lime are said to be isomorphous in
respect of 1 atom of silica; to Paranthine, in which they are
said to be isomorphous in respect of 2 atoms of silica; and
to Szz/bite, in which they stand in the same relation to 3 atoms
of silica. And 1 did this merely to adduce the inference that
all other elements which might be supposed isomorphous in
respect of 1 atom of silica, ought to be equally so when com-
bined with 2 atoms, or with 3 atoms; and hence it was unne-
cessary even to consider the water or any of the other com-
ponent elements of either of these minerals.

With regard to plesiomorphism, it does not appear that any
limit has been assigned to the difference in the plesiomorphous
angles. Silica and alumina are said to be isomorphous when
alumina acts the part of an acid. But as the question raised
is, whether the atoms of silica and alumina are isomorphous,—
unless those of alumina differ according as this substance acts
the part of acid or of base, and in this case it is not easy to
conceive what an atom means,—silica and alumina should be
isomorphous generally. Now the primary form of silica, or
quartz, is a rhomboid of 94° 15’, and that of alumina, or co-
rundum, also a rhomboid, but measuring 86° 5’. Hence these
bodies are, when they occur singly, only plesiomorphous, with
a difference in their angles of 8° 10', notwithstanding which
they are required by the theory to pass for strictly isomorphous
elements when alumina becomes a substitute for silica. When
however they enter into mutual combination in cyanite, which
is regarded as a pure silicate of alumina, both isomorphism and
plesiomorphism at once vanish, and a new class even of form
is produced, a doubly oblique prism, as irregular and remote
a form from the rhomboid as can be found amongst crystals.

How these facts are to be reconciled with the new theory,
I must leave to the better consideration of its supporters.

N.S. Vol. 10. No. 60. Dec. 1831. 3I LVI. Notices

[ 426 ]

LVI. Notices respecting New Books.

The Life of Sir Humrury Davy, Bart. LL.D. late President of the
Royal Society, Foreign Associate of the Royal Institute of France,
&c. &c. By John Ayrton Paris, M.D. Cantab. F.R.S. §c.
Fellow of the Royal College of Physicians.

[Concluded from page 386.]

FTER completing the history of the Safety-lamp, Dr. Paris

& briefly notices the Geological Society of Cornwall, and the pa-
tronage and support which it received from Sir H. Davy: to this
Society he communicated a memoir on the Geology of Cornwall,
which was published in the first volume of its Transactions. Of
this paper Dr. Paris gives an analysis, and then proceeds to exhibit
Sir Humphry in quite a new field of inquiry,—that of discovering a
method for unrolling the ancient Papyri. “ It occurred to him,” says
Dr, Paris, “‘ that as chlorine and iodine do not exert any action upon
pure carbonaceous substances, while they possess a strong attrac-
tion for hydrogen, these bodies might probably be applied with
success for the purpose of destroying the adhesive matter, without
the possibility of injuring the letters of the Papyri, the ink of the
ancients, as it is well known, being composed of charcoal. He ac-
cordingly exposed a fragment of a brown manuscript, in which the
layers were strongly adherent, to an atmosphere of chlorine ; there
was an immediate action, the papyrus smoked, and became yellow,
and the letters appeared much more distinct. After which, by the
application of heat, the layers separated from each other, and fumes
of muriatic acid were evolved. The vapour of iodine had a less
distinct, but still a very sensible action. By the simple application
of heat to a fragment in a close vessel filled with carbonic acid, or
with the vapour of zther, so regulated as to raise the temperature
very gradually, and as. gradually to reduce it, there was a marked
improvement in the texture of the papyrus, and its leaves were more
easily unrolled. In all these preliminary trials, however, he found
that the success of the experiment absolutely depended upon the
nicety with which the temperature was regulated.”

So great indeed was the care required in performing this opera-
tion, that the plan proposed was incapable of application to any
useful extent; indeed, the condition of the Papyri was such, that
it would have been sufficient to damp the ardour and paralyze the
exertion of any one less accustomed to combat and conquer dif-
ficulties than was Davy. An account of the various processes may be
found in his paper, entitled, ‘“ Some Observations and Experiments
on the Papyri found in the Ruins of Herculaneum,” which was read
before the Royal Society on the 15th of March 1821, and published
in the Transactions for that year *.

Although the liquefaction of the gases is a subject more connected
with the name of Faraday than with that of Davy, we cannot resist the
temptation to insert the following statement from Dr, Paris: “‘ Every

* This paper will also be found in the Phil. Mag. vol. lviii. p. 421.
incident,

Notices respecting New Books. 427

incident, however trifling, if it relates to a great scientific disco-
very, merits the attention of the historian, As it accidentally oc-
curred to me, and to me alone, to witness the original experiment
by which Mr. Faraday first condensed chlorine gas into a liquid,
I shall here state the circumstances under which its liquefaction was
effected.

‘«‘ [ had been invited to dine with Sir Humphry Davy, on Wed-
nesday the 5th of March 1823, for the purpose of meeting the
Rev. Uriah Tonkin, the heir of his early friend and benefactor of
that name. On quitting my house for that purpose, I perceived
that I had time to spare, and I accordingly called in my way at the
Royal Institution. Upon descending into the laboratory, I found
Mr. Faraday engaged in experiments on chlorine and its hydrate
in closed tubes. It appeared to me that the tube in which he was
operating upon this substance contained some oily matter, and
I rallied him upon the carelessness of employing soiled vessels.
Mr. Faraday, upon inspecting the tube, acknowledged the justness
of my remark, and expressed his surprise at the circumstance. In
consequence of which, he immediately proceeded to file off the
sealed end ; when, to our great astonishment, the contents suddenly
exploded, and the oily matter vanished!

“Mr, Faraday was completely at a loss to explain the occur-
rence, and proceeded to repeat the experiment with a view to its
elucidation. I was unable, however, to remain and witness the result.

«« Upon mentioning the circumstance to Sir Humphry Davy after
dinner, he appeared much surprised; and after a few moments
of apparent abstraction, he said, ‘I shall inquire about this expe-
riment to-morrow.’

‘«« Early on the next morning, I received from Mr, Faraday the
following laconic note:

“ « Dear Sir,
‘ The oil you noticed yesterday turns out to be liquid chlorine.
‘ Yours faithfully, ‘M, Farapay,’

“It is well known that, before the year 1810, the solid substance
obtained by exposing chlorine, as usually procured, to a low tem-
perature, was considered as the gas itself reduced into that form :
Sir Humphry Davy, however, corrected this error, and first showed
it to be a hydrate, the pure gas not being condensable even at a
temperature of —40° Fahrenheit.

« Mr. Faraday had taken advantage of the cold season to pro-
cure crystals of this hydrate, and was proceeding in its analysis®,
when Sir Humphry Davy suggested to him the expediency of ob-
serving what would hapnen if it were heated in a close vessel ; but
this suggestion was made in consequence of the inspection of results
already obtained by Mr. Faraday, and which must have led him to
the experiment in question, had he never communicated with Sir
Humphry Davy upon the subject. This avowal is honestly due to
Mr. Faraday.”

* The results are contained ina short paper in the Quarterly Journal of
Science, vol, xv.
$12 After

428 Notices respecting New Books.

After the numerous and long extracts which we have made from
Dr. Paris's work, we can allot but little space for further remarks,
though there are various subjects of high interest upon which we
have not bestowed a single observation; they are noticed by the
biographer with a minuteness and an accuracy worthy of the illus-
trious philosopher whose discoveries he has undertaken to record.
For an account of the share which Davy had in developing the na-
ture and properties of iodine; of his method of protecting copper
sheathing ; his experiments on electro-magnetism, and the paper on
the phenomena of volcanoes, we must refer the reader either to the
memoirs themselves*, or to Dr, Paris’s account of them. Alluding
to his retirement from the office of President of the Royal Society,
Dr. Paris remarks: ‘* To assert that Davy retained his popularity, or
to deny that he retired from the office under the frown of a consi-
derable party, would be dishonest. I would willingly dismiss this
part of his life without too nice an examination; but I am writing
a history, not an eloge.

«“ As a philosopher, his claims to admiration and respect were
allowed in all their latitude; but when he sought for the homage due
to patrician distinction, they were denied with indignation. How
strange it is, that those whom Nature has placed above their fellow
men by the god-like gift of genius, should seek from their inferiors
those distinctions which are generally the rewards of fortune, When
we learn that Congreve, in his interview with Voltaire, prided him-
self upon his fashion rather than upon his wit; that Byron was more
vain of his heraldry than of his ¢ Pilgrimage of Childe Harold;’ that
Racine pined into an atrophy, because the monarch passed him
without a recognition in the ante-room of the palace, and that Davy
sighed for patrician distinction in the chair of Newton, we can only
lament the weakness from which the choicest spirits of our nature
are not exempt. Will philosophers never feel, with Walpole, that
‘ a genius transmits more honour by blood than he can receive’ ?
Had the blood of forty generations of nobility flowed in the veins
of Davy, would his name have commanded higher homage, or his
discoveries have excited greater admiration? But great minds have
ever had their points of weakness: an inordinate admiration of
hereditary rank was the cardinal deformity of Davy’s character ; it
was the centre from which all his defects radiated, and continually
placed him in false positions ; for the man who rests his claims upon
doubtful or ill-defined pretensions, from a sense of his insecurity,
naturally becomes jealous at every apparent inattention, and he is
suspicious of the sincerity of that respect which he feels may be the
fruit.of usurpation. If with these circumstances we take into con-
sideration the existence of a natural timidity of character, which he
sought to conquer by efforts that betrayed him into awkwardness
of manner, and combine with it an irritability of temperament which
occasionally called up expressions of ill-humour, we at once possess
a clue by which we may unravel the conduct of our philosopher,

* See also Phil. Mag. vol. lviii. p. 43, 406; Ixiv. p. 30; Ixv.p. 203; and
Phil. Mag. and Annals, N.S. vol. iv. p. 85. 3
an

Notices respecting New Books. 429

and the consequences it brought upon himself during his presidency
of the Royal Society.” it vatahay

We quote this last paragraph not merely on account of its intrinsic
truth, but to show that while Dr. Paris fully appreciated the me-
rits of the philosopher, as is proved indeed by the ability with which
he has described his discoveries, he was fully aware of the weak
points of his character. We should also be happy to copy Dr.
Paris’s very able comparison of the genius of Wollaston with that
of Davy, did our limits allow.—We conclude with acknowledging
the great pleasure with which we have read Dr. Paris’s work, and
with strongly recommending it to the perusal of all who delight in
tracing the progress of genius successfully applied to the achieve-
ment of objects whose value is imperishable.

Montagu’s Ornithological Dictionary ; new edition, “ with a Plan of
Study, and many new Articles and original Observations. By Jamrs
Rennie, 4.M., A.L.8., Professor of Natural History, King’s Col-
lege, London ; Author of ‘ Insect Architecture,’ ‘ Insect Transfor-
mations,’ ‘ Architecture of Birds,’ &c.’’ London, 1831. Octavo ;
Introduction, &c. pp. Ix., Dictionary and Index, pp. 592; 28 En-
gravings on Wood.

[Continued from p. 379.]

We may here usefully make a few observations on the distinction
between what is properly called the Natural System and Artificial
Systems ; as much needless controversy (in our opinion) has ensued
upon this particular subject, to which we have already alluded in
p- 376. An artificial system, then, as we conceive, is merely an
arrangement of species, according to some particular character or
characters selected for the purpose, into such groups, of greater or
less magnitude, as will enable the naturalist to recognize any species
which he may discover or observe, and by ascertaining its place and
denomination ir the system, obtain a clue to direct him to all the
sources of information respecting it, and thus to become acquainted
with its importance and value, whether as an object of philosophical
investigation, or as one of utility to mankind; or if the species be
new (which point it will also determine), it will enable him to define
it, and give it its proper place in the system, for future reference.
Of such a system, and of the use of such a system, the Linnean
Systema Plantarum, in which the beings of the vegetable kingdom
are thus eclectically arranged, according to the characters of the
fructification, is an eminent example.

The Natural System, e contra, is the distribution of species into a
series, according to the mutual relations subsisting between them,
ascertained by observing the totality of their characters ; not by se-
lecting any individual character, or individual set of characters, to
serve as the basis of classification. And whether the visible exponent
of this system be a series of specimens of the species themselves, a
linear representation of it in a diagram, or a verbal expression of it in
a book, it is still, in either shape, as a branch of science, the Natural
System ; being, as we have before observed, all that man can know

or

4:30 Notices respecting New Books.

or possess of the system actually existing in the creation. Of this
system, we cite the arrangement of the Animal Kingdom, and espe-
cially of the Annulosa, given in Mr. Macleay’s Hore Entomologice,
as being the first approximation to, with respect to the Animal King-
dem generally; and Mr. Vigors’s arrangement of Birds, Mr. Macleay’s
arrangement of the Coleoptera Chilopodomorpha of Java, and Dr. Hors-
field's of the Lepidoptera Diurna of the same island and other parts of
India, together with some other essays, as other approximations to, in
different parts of the animal series. The Jussieuian system of plants, so
far as the distribution of species into what are called natural orders is
concerned, and certain essays of Mr. R. Brown, especially his Prodromus
Flore Nove Hollandia, are also examples of approximations to it, as
existing in the Vegetable Kingdom ; though in many respects, we ap-
prehend, of a more remote nature than the former. While the Régne
Animal of Cuvier, we conceive, presents a mixture of artificial systems
on various plans, with portions of the true natural system, detected by
the sagacity of its illustrious author, and by that of his predecessors
and his contemporaries.

But Mr. Macleay has himself furnished us with an illustration of the
distinction between an artificial system and the natural system, which
on account of its clearness and effect we will now give in his own words.

“<Were the planets to be arranged in a table according to any one
of their properties,—as for -instance, the period of rotation on their
several axes,—such asystem would be artificial, and only useful in
that, having observed the length of a rotation, areference to the table
would be a convenient mode of determining the name of the planet.
But no one would ever think of confounding this artificial table or
system with the system of the universe [meaning thereby our solar
system]; although an error exactly similar is every day committed in
natural history, when a person ah may by the mere exercise of his
memory have become acquainted with an artificial table, fancies that
he must therefore be a profound naturalist.”— Hor. Ent. pref. p. xi.

Now we think the above a very just illustration of the subject; the
supposed table of the planets arranged according to their respective
periods of rotation, being an exact exemplification of an artificial system
in natural history ; and a graphic representation of the actually ob-
served arrangement of them about the sun, or a verbal description or
other expression of it in a book, being the same thing, with respect to
them, that the natural system, or an approximation to it, is, with re-
spect to the species of animals or of plants ; with the exception, that,
in the case of the planets, the natural system actually exists (as a
system) in space, but that in the case of the species of animals and
plants, it is not exhibited in space; but is the result of induction from
particular instances, each particular instance itself consisting of a
group of animals or of plants previously ascertained, by observation
and that spontaneous induction which is almost coincident with it, to
be natural assemblages.

This mode of considering the subject leads us to another point
which appears to be of some importance, and which will probably tend
to show the true relation of the mode of investigating nature introduced

into

Notices respecting New Books. 431

into natural history by Mr. Macleay and his disciples, to that which
has long been pursued in dynamics, astronomy, and other depart-
ments of general physics. This is a point on which we feel some
anxiety, for we are of opinion that Mr. Macleay’s discoveries, and
they alone, have at length raised the study of Natural History toa
level with the higher Physics. And as the cultivators of the latter do
not as yet appear adequately to appreciate the dignity, as a branch of
inductive science, of Natural History, we are on that account also glad
to have this opportunity of drawing their attention to the subject, by
stating what we believe to be the correct view of it in this respect.

The assembling of species into groups, then, according to the tota-

lity of the characters of every species, and the variation of those cha-
racters, and of the groups so established into greater groups, by the
same process, is, we conceive, precisely analogous to what Mr. Her-
schel, in his Preliminary Discourse on the Study of Natural Philosophy,
terms “ the first stage of induction” that is, the discovery of proximate
causes, and laws of the lowest degree of generality, in physics. And
the investigation of the abstract principles of affinity and analogy ;
of the true nature of what Mr. Macleay has called osculant groups ; of
the intimate quality of the affinity of transultation ; of that of the
process by which, in the union of contiguous groups of a certain rank,
the relation of analogy insensibly becomes a relation of affinity, &c.,
are as precisely analogous to the higker degrees of inductive genera-
lization, in physics. With the above, other considerations are con-
nected, which may throw some degree of light on the misconceptions
which have been broached on the subject we have already twice no-
ticed, the true claims of the Macleayan system to be that of nature,
and which are ina manner sneered at by Mr. Rennie, in his introduc-
tory page examined in p. 375—379.
’ We will return to Mr. Macleay’s illustration of the difference be-
tween an artificial system and that of nature, by allusion to a sup-
posed and to the real arrangement of the planets composing our solar
system. Pursuing this illustration, we affirm, that the discovery of
the natural system by the means adopted by Mr. Macleay and the
naturalists of his school, is closely analogous to, is as strictly induc-
tive, as truly logical, and claims as much the regard of every reflect-
ing mind, as, the discovery of the natural system of the planetary and
sidereal universe, by the means, appropriate to that sphere of re-
search, which have been adopted by astronomers and mathematicians.
For the further use of this illustration we will extend it ; we will re-
gard the natural system of the planets as being, not merely their ar-
rangement, as circulating around the sun, and the knowledge of it,
but as the assemblage of laws which govern their motions, and of
proximate or remote causes of their phenomena,

The natural system of the planets, taking that term in its lowest
acceptation, was, as is well known, discovered by Copernicus. But
his discovery, although complete in itself, although consisting of de-
monstrated truths, did not extend to the entire natural system of these
bodies ; although the system promulgated was, in the proper sense of
the term, a natural one, yet much remained to be discovered of that

system.

4.32 Notices respecting New Books.

system. Accordingly the system was extended by Kepler's discovery
of the proportions between the times of revolution of the planets and
their distances from the sun. Again, after Kepler had promulgated his
discoveries, Galileo discovered the satellites of Jupiter, and by ob-
servations on these, Kepler saw it ascertained that the law which he
had discovered to apply to the revolutions of the planets around the
sun, held good also when applied to the periods of circulation of the
satellites of Jupiter around that planet; “‘ thus demonstrating it to
be something more than a mere empirical rule, and to depend on the
intimate nature of planetary motion itself.”* But it was left for the
genius of Newton to complete, to a certain degree of generality, the
natural system of the planets which had been discovered by his pre-
decessors. It was shown by him, in the Principia, that all the celes-
tial motions which had down to his time been made known, were
consequences of one simple law of attraction. And the consequences
of this law, called that of gravitation, have been since pursued, through
all their intricacies, by Clairaut, D’Alembert, Euler, Lagrange, and
Laplace ; and they are still pursuing by the successors of those philo-
sophers,—by Ivory, Herschel, Airy, Lubbock, Poisson,and many others.

Now all this, we observe, is nothing but a series of investigations
having for their object the discovery of what, in Astronomy, exactly
answers to the natural system (now using that term in the highest
and most comprehensive sense) in Natural History ; and each con-
tributor, whether practical observer or mathematician, actually has
discovered some part of that system,—some portion of what was in-
cluded in the general natural system discovered by Copernicus, which
remained unknown until the time of the particular discoverer. It
will of course be remembered that we are comparing the progress
made in Astronomy with that of Natural History, here, merely for
the purpose of illustrating what we conceive to be the legitimate ob-
ject of the investigations of both, the discovery of the natural system ;
and that the two sciences have been regarded as comparable, mutatis
mutandis only. And in the further comparison which follows, we beg
it to be observed that we are not in any manner intending to make
out a parallel, as to genius or scientific character, between the philo-
sophers we have named as the successive discoverers of the natural
system in astronomy with the naturalists we are about to name, as,
among others, the discoverers of the natural system in Zoology. We
presume not to offer any opinion on this point.

One of the reasons which have induced us to enter upon this detail
of illustration, is the idea which has often been expressed, both orally
at various scientific meetings, and also in print, that the discovery of
the natural system is a thing which cannot or ought not to be aimed
at—that it is not a legitimate object of science. Our opinion being
diametrically opposite to this, we wish to show that what Mr. Mac-
leay and the naturalists of his school are endeavouring to accom-
plish for Natural History, exactly corresponds to what Copernicus,
Kepler, Newton, and Laplace have accomplished in part for Astro-

* Herschel’s Preliminary Discourse, p. 269.
nomy,

Geological Society. 433

nomy, and what Ivory, and Lubbock, and Poisson, &c., are still con-
tributing fresh truths to. They aim at nothing more; but they aim at
nothing less.

The natural distribution of the Animal Kingdom then, as given in
Mr. Macleay’s Hore Entomologice, may be compared, in a general
manner, with the natural system of the Planets, as discovered, equally
by the method of induction, by Copernicus ; and the additions to and
extensions of that distribution, which Mr. Vigors has produced with
respect to Birds, Dr. Horsfield with respect to Lepidopterous Insects,
&c., may be compared with the further unfolding of the planetary sy-
stem by the labours of the successors of Copernicus. We do not pre-
sume to assert that the labours of these latter naturalists are of equal
degree or rank, as contributions to Natural History, with the discoveries
of Kepler and Galileo, as contributions to Astronomy ;—we give no
opinion on this point—but we affirm that they have extended the
knowledge of the natural system of animated nature, communicated
by Mr. Macleay, in like manner as Kepler and Galileo extended that
communicated by Copernicus of the natural system of the planets. We
certainly are of opinion, however, that Mr. Macleay’s discovery of the
natural system in Zoology is of similar importance as a contribution
to that science, to what the discovery by Copernicus of the natural
system of the planets was as a contribution to Astronomy; and that
it will lead to results, in the researches of the naturalists of future
ages, as important as those which Kepler, Galileo, Newton, and their
successors have effected in the development of the particular “ natu-
ral system” which formed their object of pursuit.

Sept. 29, 1831. (To be continued. ]

LVII. Proceedings of Learned Societies.

GEOLOGICAL SOCIETY.

Nov. pawl Weel Society assembled this evening for the Ses-

sion.

A paper was read, “ On certain younger deposits in Sicily, and on
the phenomena accompanying their elevation.” By Dr. Turnbull
Christie, F.G.S., and communicated by the President.

The observations contained in this essay were made partly during
a short visit to Palermo, and partly on an excursion in which the
author travelled from Palermo along the northern coast as far as the
Castello di Tusa, crossed the central chain of mountains by way of
Mistretta and the Monte di Castellito Nicosia, Leonforte, and Castro-
Giovanni, turned eastward by way of San Filippo d’Argire to Ca-
tania, and then proceeded along the east coast by Lentini, Syracuse,
and Noto to Cape Passero, where he embarked for Malta. In this
route he had an opportunity of examining most of the principal stra-
tified formations in Sicily, and hopes to have clearly determined the
exact place in the geological series to which many of them must be
referred.

The formations described by the author are arranged under the
eight following divisions :—

N.S. Vol. 10. No, 60. Dec. 1831. 3K 1, The

434 Geological Society.

1. The oldest formation which he met with is, a sandstone with a
few subordinate beds of marl and limestone, occupying a great portion
of the central chain of the island, and extending along part of the
northern coast. Its exact age he was unable during his rapid tour to
determine; but it is older than the Jura or Apennine limestone. In
travelling along the coast eastward from Palermo, the author first
came on this sandstone near the river Pilato, a few miles to the west
of Cefalu; and the island eastward of this point principally consists
of the same rock and its accompanying shales. In his route thence to
Mistretta he passed over the great chain of the island, which in this
part consists entirely of this sandstone, and attains a very great ele-
vation. The mountain of Sancta Diana rises 3875 feet above the
level of the sea, and is overtopped by many others within sight, on
the loftiest of which, the Madonia, patches of snow were still visible
on the 8th of June.

The dip of the sandstone strata is various ; but they are in general
highly inclined, and sometimes vertical. Their direction is for the
most part parallel to the general direction of the chain itself,—namely,
inclining from the north of east to the south of west. At Mistretta
the strata are seen distinctly to dip away from an anticlinal line,
which passes across the mountain of Sancta Diana, extends between
the hill on which the castle stands, and the small hill of S. Catarina
on its north, and thence across the valley to the east of Mistretta.
At the Monte di Castelli, the highest point near Mistretta, the strata
have two different bearings, one nearly east and west, and the other
north and south: and a similar observation was made at Nicosia.
The author directs attention to the fact, as indicative of the central
chain having been raised during at least two distinct periods of ele-
vation.

2. The formation next in order to the sandstone, and of more recent
origin, is the limestone and dolomite composing the north-western
part of the island, and which the author considers as the equivalent
of the Jura or Apennine limestone. It rises in bold, precipitous cliffs
flanking the bay of Palermo, and at the distance of about two miles
inland bounds the rich plain which lies along the coast. The dolomite
closely resembles that of the Tyrol, presenting a bold, rugged outline,
without a trace of stratification, and having its naked sides traversed by
numerous rents and fissures. Caves, sometimes containing bones, are
frequent, formed probably by the enlargement of fissures by the action
of water. The limestone, which frequently contains magnesia, is
stratified, and the strata are often highly inclined.

3. The third formation distinguished by the author consists of marls
and limestones containing Nummulites and Hippurites, and which he
believes to belong to the chalk and green-sand formations of other
parts of Europe. These beds are horizontal, and lie on trap-tufa and
basalt. They were observed at the most southern extremity of Sicily:
they extend from the village of Pachino to the sea—occupy the upper
part of the island of Cape Passero—and form the base of the small
island named the Isola delle Correnti.

4, The next rocks in the series are cretaceous limestones and marls

of

Geological Society. 435

of the older tertiary epoch. In theorder of superposition they occupy
a place immediately below the tertiary limestone next te be described,
which contains shells of existing Mediterranean species, and is hence
probably of much more recent origin.

5. The fifth formation is an extensive tertiary limestone, found both
north and south of the great central range. Its prevailing character is
that of a coarse, yellowish or white limestone, extensively quarried in
several places as a building inaterial. Most of its shells belong to
species now existing in the Mediterranean, the most abundant being
Pectens and Oysters. The genera Cardiwm, Pectunculus, Arca, with
Echini, Serpule, and Corals, are also very common. In the plain of
Palermo the strata are perfectly rorizontal; but in the valley of the
Oretus, where they lie close upon the dolomitic limestone, they are
considerably inclined, and are higher by 100 feet than in the plain.
A similar disturbance was observed at the Cape delle Mandre. At
the south of the central chain the tertiary rocks are still more dis-
turbed, being elevated to several thousand feet above the level of the
sea. The direction of these inclined strata is parallel to that of the
principal chain.

6. The next formation is a conglomerate still more recent than the
upper tertiary beds last mentioned, and containing shells of species
now existing in the Mediterranean. Its character varies in different
situations, according to the nature of the rocks of which it is com-
posed. It may be studied us well on the north coast as in the valleys
to the south of the central chain, especially in that of the Limetus,
between Palermo and Catania, and to the south of Syracuse. Its
position, as well as fragments of tertiary rocks contained in it, prove
it to be posterior to these ; its sea shells attest its marine origin ; and
the perforations by Lithodomi prove it to have been covered by the
waves prior to its elevation.

7. Of the same age with the preceding conglomerate is the Bone-
breccia. Three bone-caves are enumerated by the author as situated
in the immediate neighbourhood of Palermo. One of them, the Grotta
de San Ciro, about two miles south-east of the town, is situated near
the base of the magnesiferous limestone mountain of Grifoni, close upon
the plain of Palermo; while the other two are in the mountain of
Beliemi, about four miles to the west of the town, at a considerable
elevation, being more than 300 feet above the level of the sea, and 100
feet higher than the ¢ave at San Ciro,

The breccia at San Ciro is not confined to the cave itself, but forms
a great part of the external talus, where it rests immediately on the
upper tertiary beds, and has a thickness of about 20 feet. The breccia
consists of numerous fragments of bones, with some rolled pieces and
blocks of limestone cemented together by a little lime or clay; and
it has some appearance of stratification, indicative of a deposit from
water. The bones have been pronounced by Baron Cuvier to have
been those of the Elephant, Hippopotamus, and Deer, with a few of
a carnivorous animal of the genus Canis.

The author infers from a careful personal examination, that this

3K 2 breccia

436 Geological Society.

breccia was deposited by water, and that subsequently to its formation
and prior to its elevation, it remained long under the waves. This
conclusion he believes to be justified by the appearance exhibited by
the sides of the cave, which in some parts are smooth and polished as
if long worn by water, and at others are perforated by Lithodomi.
In this opinion he considers himself fully borne out by a bone-breccia
lately discovered near the bay of Syracuse, about 70 feet above the
level of the sea, and deposited in caves worn in the tertiary rocks.
This breccia is of the same age as that at San Ciro, contains the
bones of similar extinct quadrupeds, is intermixed with sea-shells, and
has not only been worn by water since its formation, but its substance
has been perforated by Lithodomi. From all these circumstances,
considered in conjunction with the extent of the preceding newest
tertiary deposits, the author considers it certain that the extinct qua-
drupeds, the bones of which are contained in the breccia, must have
lived at a period long posterior to that in which the Mediterranean
began to be inhabited by its present species of Mollusca, Radiata,
and Zoophytes, and before the last convulsion which raised a great
part of Sicily above the level of the sea.

The caves at Beliemi were not so minutely examined by the author
as that at San Ciro. In one respect they possess much interest. They
are situated at a greater height than the tertiary rocks have attained
in that neighbourhood; and neither the caves themselves nor the
bone-breccia have any appearance of marine action. The author
thence infers that the breccia at Beliemi was above the surface of the
sea at the time that the breccia at San Ciro was beneath it ; and that
their present heights mark the extent to which the tertiary formation
at that part has been raised by the great convulsion, by which a
large portion of Sicily has been elevated.

8. The last formation noticed by Dr. Christie is diluvium, of which
he distinguishes two kinds differing in age. The older diluvium—an-
swering, he conceives, to the terrain de transport ancien of Elie de
Beaumont—consists of large rolled fragments of sandstone, with a
few fragments of the tertiary rocks cemented by a sandy clay, is of
the same age as the conglomerate and bone breccia, and occupies
considerable heights on the sides and summits of the hills. The newer
diluvium is quite distinct from the preceding, occupies only the bottom
of the valleys, sometimes to great depth, and consists partly of rolled
fragments of older rocks, even of the conglomerate, together with a
great quantity of grey clay. They may both be distinctly seen in the
valley of the Limetus.

In addition to the general conclusions already mentioned in the
history of the bone-breccia, the author considers his observations as
affording complete confirmation of the views of Elie de Beaumont re-
garding the epochs of elevation of the Sicilian mountains. The prin-
cipal chain, extending across the island to the north of Castro Novo
and Nicosia towards Messina, is not only sensibly parallel to the
principal chain of the Alps, whence alone, according to Elie de Beau-
mont, the date of elevation must be the same; but the author con-

tends

Linnean Society. 437

tends that both chains were elevated posterior to the formation of the
conglomerate and older diluvium, and therefore that their periods of
elevation are identical.

LINNZEAN SOCIETY.

Nov. 1 and 15.—A Paper was read on the Sexual Organs and
mode of Impregnation in Orchidee and Asclepiadee. By R. Brown,
Esq:, V-P.L.S., &c. &e.

Mr. Brown's principal object in this paper is to detail some obser-
vations on the structure and ceconomy of the fecundating organs in
these families, made by him chiefly in the present year. They have
hitherto presented the most important objections to the prevailing
theories of vegetable fecundation: but Mr. Brown thinks we are now
as far advanced with respect to this function in these families, as in
any other tribe of Phenogamous plants ; and that upon the general
problem of generation, additional light is more likely to be derived
from them than any other part of the vegetable or animal kingdom.

Orchidee.—Two opinions have been entertained as to the mode of
impregnation in this family. Haller, Adanson, Curtis, C. K. Spren-
gel, J. K. Wachter, Schkuhr, Swartz, Salisbury, and Treviranus
considered the direct application of the pollen to the stigma as essen-
tial to fecundation : while others, as Linneus, Schmidel, Koelreuter,
Stokes, Batsch, Richard, Du Petit Thouars, Link, Lindley, Bauer, and
Mr. Brown himself, from the peculiarities observable in the structure
and relative position of the sexual organs, have considered the direct
contact of the pollen mass and stigma as improbable, and have con-
sequently had recourse to other explanations of this function.

Wachter in 1799 was the first who succeeded in impregnating an
orchideous plant by applying the pollen to the stigma,—a result
which was confirmed in 1804 by Salisbury, and twenty years after
by Treviranus.

These observers have sufficiently proved that impregnation is ac-
complished by the direct application of pollen to stigma: but no sub-
sequent phenomena resulting from the action of the stigma on the
pollen is noticed.

Those authors who conceived that the pollen mass could not come
into direct contact with the stigma, have attempted to explain the fe-
cundation of Orchidee@ in various ways.

Batsch in 1791 supposed that the only way in which the pollen
could act on the ovarium in Ophrydece was by the retrogradation of
the impregnating power through the caudicula to the gland beneath
it; and this opinion was also that of Richard, who applied it to the
whole order, and was entertained by Mr. Brown in 1810. It was
also the opinion of Mr. Bauer, to whom it appears to have occurred
as early as 1792.

The opinion of Du Petit Thouars was peculiar. He considered that
the glutinous substance connecting the grains of pollen was the fe-
cundating matter ; that the elastic pedicel of the pollen mass, not
formed before expansion, consisted of this gluten ; and that in the
expanded fiower, the gluten which has escaped from the pollen is, 4:

all

438 Linnean Society.

all cases, in communication with the stigma. The stigma he describes
as a glutinous disk, from which a central cord of the same nature is
continued through the style to the ovarium, where it divides into three
branches, each of which divides into two, the six branches so formed
running down, one on each side of the corresponding placenta to the
base, giving off rainuli, which go to the ovula and separate them into
groups. A communication is thus, in his opinion, established be-
tween the anthera and ovula, which he supposed were impregnated
by an aura seminalis through their surface, and not, as he believes
to take place in other families, through the funiculus.

In the spring of this year Mr. Brown renewed his observations on
this family, and the results of his investigations are very curious and
important. His attention was first directed to the relation which the
lateral and generally rudimentary stamina bear to the other parts of the
flower ; and fully satisfied himself, that the opinion which he had ex-
pressed in his observations upon 4postasia was correct, viz. that they
are placed opposite to the two lateral divisions of the inner series of
the perianthium, and not, as had been before suppused, to the lateral
divisions of its outer series. He then turned his attention to the
composition of the stigma with respect to the relation which its lobes
bear to the other parts of the flower and to the component parts of
the ovarium. He satisfied himself that Orchidee have in reality three
stigmata more or less confluent in general, but in some cases distinct,
and even furnished with styles of some length. > These stigmata are
opposite to the three outer divisions of the perianthium, and conse-
quently terminate the axes of the component parts of the ovarium,
which he regards as composed of three simple ovaria united by their
ovuliferous margins,—a structure in which the ordinary relation of
stigmata to placente is that here found.

In Cypripedium and Apostasia, in which the lateral stamina are
perfect, and the middle one without anthera, all the lobes of the
stigma are equally developed and of nearly similar form and texture,
and, as Mr, Brown has proved by experiment in Cypripedium, are all
equally capable of performing the function of the organ. But in
most cases, that lobe which is opposite to the middle and perfect
stamen and deriving its vessels from the same cord, does not perform
the function of the organ, there being hardly an instance of a per-
fectly developed stamen and stigma placed opposite to each other,
and having the same vascular supply. To this lobe the glands al-
ways belong, to which the pollen masses become attached, but from
which they are always originally distinct. Its office, therefore, is essen-
tially different from the lateral lobes, which are always present, more
or less developed, and capable of performing their proper office.
These lateral lobes are most developed in Satyrine or Ophrydea,
especially in Bonatea speciosa, in which they have been mistaken for
portions of the labellum. That they are, however, actually the effi-
cient stigmata Mr, Brown has proved by experiment, in applying the
pollen mass to their secreting surface, which was followed by the en-
largement of the ovarium, [n the ordinary structure, therefore, of
Orchidee, in which only one perfect stamen is produced, the corre-

sponding

Linnean Society. 439

sponding stigma loses entirely or in part its function, which it re-
_gains in those cases where this stamen is destitute of anthera; and
hence these organs, when perfect, are never placed opposite, but
always alternate with each other,

The tissue of the perfect stigmata in Orchidee is not materiaily
different from that of other plants. It consists of densely approxi-
mated utriculi, which enlarge, and are subsequently separated from
each other by a viscid secretion. The channel of the style has a si-
milar structure, and undergoes similar changes previous to impreg-
nation. In the unimpregnated ovarium, the upper portions which
correspond to the axes of the placenta, but which do not bear ovula,
are neither secreting, nor do they consist of utriculi like those of the
cavity of the style: and the same is observable in the six lines mar-
ginal to the three placente; and these lines, both above and at the
margins of the placente, Mr. Brown calls the conducting surfaces of
the ovarium.

The female organ is now in a proper state to be acted upon by the
pollen; and Mr. Brown has satisfied himself that it acts by being
brought into contact with the stigma, as Treviranus’s experiments
proved, He applied the pollen to the stigmata in several tribes of
Orchidee, and found that its grains, either in the entire mass or se-
parately, soon produced tubes or boyauz, like those first described by
Amici and Brongniart. One tube is emitted from a simple grain of
pollen, their number consequently corresponding to that of the cells
of the compound grain. These tubes acquire a great length, even
while adhering to the grains which produce them, and have a diame-
ter less than zy'yoth part of an inch. They eventually separate from
the grain while immersed in the viscid secretion of the stigma. They
are cylindrical, neither branched nor jointed, with apparent interrup-
tions within, probably from partial coagulations, on the walls, of the
contained fluid. With a magnifying power of 150 Mr. Brown has
not been able to observe granules in them even in their earliest state.
With a power of 300 or 400, an extremely minute transparent gra-
nular matter may be detected.

The tubes thus produced from the pollen mass are generally very
numerous, and form a cord, which passes through the channel of the
stigma orstyle. On reaching the cavity of the ovarium, this cord divides
into three parts, which are applied to those upper axes of the valves
which are not placentiferous, and at the top of each placenta each of
these three cords again divides into two branches, the six ultimate divi-
sions thus produced passing down along the margins of the placente,
along what has before been called the conducting surfaces of the ova-
rium. They descend to the base of the placenta, with which they are
nearly in contact; but Mr. Brown has not been able satisfactorily to
trace branches from them mixing with the ovula. These cords are en-
tirely composed of pollen tubes, and are undoubtedly essential to fe-
cundation, but in what manner they operate is unknown. Mr. Brown
adopts the opinion of M, Brongniart, that the doyaux are derived from
the inner membrane of the grain, and believes the correctness of this
opinion to be demonstrated in Asclepiadee, in which the membranes

are

440 Linnean Society.

are entirely distinct. Their production he considers a vital action
excited in the grain by the application of an external stimulus, which
is afforded by the secretion on the surface of the stigma ; and they
derive nutriment either from the particles contained in the grain, or
from the conducting surfaces with which they are in contact.

The first visible effect of the action of the pollen on the stigma is
the enlargement of the ovarium, which, in those cases where it was
reversed by torsion, untwists and resumes its original position.

After impregnation the ovulum enlarges, the nucleus disappears,
probably from its acquiring greater transparency, and becoming con-
fluent with the substance of the testa: soon after, a minute speck
about the middle of the testa becomes visible, which is the commence-
ment of the future embryo. At this period a thread may be traced
from its apex nearly to the open end of the testa, consisting of a
simple series of short cells, the lowermost one of which is probably the
original state of what, from enlargement and deposition of granular
matter, becomes the opake speck or rudiment of the embryo ; the only
appreciable changes in which are its increase in size and eventual cel-
lular structure. In the ripe state it forms an ovate or spherical body,
consisting of an uniform cellular tissue covered by a thin membrane,
the base of which exhibits no indications of original attachment at
that point, while at the apex the remains of the lower shrivelled joints
of the thread are still often visible. The embryo, therefore, would be
without albumen; the germinating point its apex, or that where the
cellular thread is found ; and the seed and funiculus are without ves-
sels.

Asclepiadee.—The mode of impregnation in this family was sup-
posed by Jussieu, Richard, Bauer, Treviranus, and by Mr. Brown, to
be indirect; that is, that there was no immediate contact of the pollen
with the stigma, but that the fecundating matter was conveyed from
the mass through the arm and gland to the female organ.

At a very early period Gleichen had observed that the pollen masses
were originally distinct from the glands,—a fact which Mr. Brown had
afterwards stated in 1809, and which had equally been observed and
delineated by Mr. Bauer. Gleichen also states, that before the masses
unite with the glands they are removed from the cells of the anthera,
and implanted into the wall of the tube which surrounds the ovaria,
and that in this situation a white viscid substance hangs to them,
which consists of tubes containing globules; and these tubes and
their contents he considers as the early preparation for the formation
of pollen. He remarks, that the tops of the styles are not originally
connected with the pentagonal body, and therefore, that impregnation
does not usually take place until the true stigmata, or those extre-
mities of the styles on which vesicles and threads are observable, have |
penetrated through the substance of the pentagonal body, and are on
a level with its apex. At the same time, he is disposed to believe that
insects may occasionally assist in the function by carrying the fecun-
dating matter directly to the stigmata, even before they enter the
pentagonal body.

Sprengel in 1793 asserts that insects extract the pollen —

rom

Linnean Society. 44]

from the cells, and apply them to the apex of the stigma, which, being
a secreting part, is calculated to act on the oily matter exuding from
the surface of the pollen mass.

In 1829 Ehrenberg describes the grains of pollen as contained in
the proper membrane of the mass, which bursts in a regular manner,
and as having each a tube, which tubes collectively are directed
towards the point of dehiscence.: He does not say how they communi-
cate with the stigma, and supposes that they form an integrant part
of the grain, without being produced by the action of an external sti-
mulus.

In July last Mr. Brown resumed his investigations into the struc-
ture and functions of the organs of this family. He verifies observa-
tions made by Mr. Bauer so early as 1805, that the masses are cellu-
lar, each cell containing a single grain. These cells he considers as
the outer membranes of the grains of which the inner membranes are
the grains described by Treviranus without tubes, and by Ehrenberg
after their production.

He found that the agency of insects was necessary to effect fecun-
dation ; that the pollen masses were actually removed from the cell
of the anthera, and immersed in the fissures formed by the projecting
ale of the anther, the descending process of the stigma near its
flexure being broken, so that the mass was entirely separated from
the gland. The pollen mass was so placed in the fissure, that its
inner or convex edge was closely pressed to that point where the tube
of the united filaments is joined to the base of the corresponding an-
gie of the stigma. On separating them, a white cord, consisting of
slender tubes, was observed issuing from the gibbous part of the edge
which had burst. On opening the mass, these tubes were found to
proceed each from a grain of pollen, all directed towards the aperture.
They were like those described in Orchidee. The cord had opened
a passage for itself through the membrane, or, rather, had separated
the upper edge of this membrane from the base of the stigma, to
which it was before united. It then passed along the surface of the
base of the stigma until it arrived at its articulation with the two
styles ; then inclined towards the inner side of the apex, which is in
some degree exposed. On opening the cavity of the style, the cord
was seen passing down the centre to the commencement of the pla-
centa, where it appears to terminate.

These appearances, which were the result of the application of the
pollen to the base of the stigma by insects, were equally obtained by
Mr. Brown’s removal and application of the mass. He found that the
convex edge of the mass must be the part applied, though he could
detect nothing peculiar in its structure or appearance. At present
he has not had sufficient opportunities to discover how impregnation
is effected in those plants of this family which have erect pollen
masses ; for though he has succeeded in producing the tubes in Hoya
carnosa, he could not get them to communicate with the stigma, nor
can he conjecture how this is to be effected.

N. S. Vol. 10. No. 60. Dec. 1831. col ASTRO-

44.2 Astronomical Socrety.

ASTRONOMICAL SOCIETY.

June 10.—The following communications were read :—

I. Observed occultation of Jupiter and his satellites by the moon,
June 1, i831.

1. By the Astronomer Royal, giving the contact, immersion of
Jupiter’s centre, and total immersion, by four observers; and the
emersions of Jupiter and the four satellites, by seven observers,

2. By Mr. Snow, containing the complete observations of all the
immersions and emersions, made in Savile Row, together with the
observed transits by which the clock error was determined.

Mr. Snow observes :

«‘ Between the contact of the moon’s limb with the planet, and
the planet’s disappearance, 1' 32" elapsed; and during that time
no change of light, colour, or motion, took place in the planet,
which remained uniformly of a rather more dusky colour than the
moon. Soth the planet and moon were in a violent state of undu-
lation during the immersion; but the moon’s undulation was seen
quite distinctly upon the planet’s disc, and differed, for that small
arc, inno respect from the undulation of the rest of the limb. I
watched very particularly for any projection of the planet upon the
moon’s edge, but could see none.

«It is perhaps worth mentioning, that the planet’s second limb,
during, and for several seconds after its final emersion, and in both
states of the adjustment of the telescope, appeared to have a very
considerable curvature towards the moon’s dark limb. The planet,
however, soon returned to a shape nearly spheroidal.”

3. By Captain Smyth, containing the same observations. Captain
Smyth also remarks:

« Although the emersions of the satellites were perfectly distinct,
they were certainly not so instantaneous as those of the small stars;
which I think was more owing to light than disc. Jupiter entered
into contact rather sluggishly; but though the lunar limb was
tremulous from haze, there was not the slightest loss of light.
Faint scintillating rays preceded the emersion, which was so gra-
dual, that, as the planet re-appeared, the edge of the moon covered
it with a perfectly even and black segment, which cut the belts
distinctly, and formed clear sharp cusps, slowly altering until the
whole body was clear. There was no appearance of raggedness
from lunar mountains, and Jupiter’s belts were superbly plain while
emerging; but there was not the slightest distortion of figure,
diminution of light, or change of colour.”

In allusion to the deviation seen by Messrs. Ross and Comfield,
which is inserted in the Memoirs, Captain Smyth mentions the
following fact:

«“ On Thursday the 26th of June, 1828, the moon being nearly
full, and the evening extremely fine, I was watching the second
satellite of Jupiter as it gradually approached to transit its disc.
My instrument was an excellent refractor, of 3? inches apenare:

an

Astronomical Society. 443

and 5 feet focal length, with a power of 100. It appeared in contact
at about half-past 10, by inference, and for some minutes remained
on the edge of the limb, presenting an appearance not unlike that
of the lunar mountains coming into view during the first quarter of
the moon, until it finally disappeared on the body of the planet.
At least twelve or thirteen minutes must have elapsed, when, acci-
dentally turning to Jupiter again, to my astonishment I perceived
the same satellite owtsede the disc! It was in the same position as
to being ina line with the apparent lower belt, where it remained
distinctly visible for at least four minutes, and then suddenly va-
nished.”

The same phenomenon was also observed on the same evening,
at different places, by Mr. Maclear and Dr. Pearson.

Il. A letter from Mr. Dawes to Mr. Herschel, giving observa-
tions of the double stars, 70 Ophiuchi, £ Urse Majoris, 44 Bootis,
y Virginis, y and « Coronz, Castor, y Leonis, ands Bootis, made
during the last and present year. Mr. Dawes is of opinion that the
apparent discs are more affected by the aperture of the telescope
than by any other circumstance; and that this is the principal
reason why a reflector presents a smaller image of a fixed star than
an achromatic of equal illuminating power.

III. The reading of Mr. Herschel’s paper on the measures of
364 double stars was completed.

This paper contains the micrometrical measures of the angles
of position and distances of 364 double stars, observed by Mr. Her-
schel with the seven-feet equatorial in his possession at Slough, the
same which was used by Sir James South in his observations at
Passy, and in a part of the measures of double stars in the Phzloso-
phical Transactions for 1824. The individual measures, being too
numerous, are not stated; but the mean results of each night’s ob-
servation are set down in tabular order, with a weight attributed to
each, indicative of the degree of confidence which the observer him-
self attributes to them, and with notes attached, descriptive of any
peculiar circumstances in the observation proper to be recorded.
They comprise the results of 735 sets of measures, or from 6000 to
8000 individual observations, obtained under all atmospheric cir-
cumstances, in the years 1828, 1829, and 1830. Almost all the
stars observed are taken from the great catalogue of Struve.

The author prefaces his observations by a comparison of his
results with those already obtained by other observers in the cases
where his stars have been observed by others, and draws a conclu-
sion not unfavourable to the general accuracy of his angles of posi-
tion ; although, in some individual cases, considerable discrepancies
and even grievous errors are admitted, In the course of this com-
parison he is Jed to point out, some stars as having so materially
changed, at least apparently, that he is induced to recommend them
for further observation, as being possibly of a binary nature. With
regard to his distances, he professes himself much dissatisfied, owing
to an imperfection in the micrometer attached to the instrument,

$3L2 whieh

Adds Astronomical Society.

which is the same with that used in all its former measurements,
and of which the cause has been detected too late to remedy the
evil.

After noticing some peculiarities in his mode of observation,
and in particular its use of a red illumination of the wires, which
he regards as a great improvement, he enters into a more particular
examination of the bearing of his present results on the theory and
history of the following stars, whose motions he considers as fully
demonstrated by them, although some of them had previously been
brought into question.

9 Cassiopee. y Virginis. 39 Draconis,

9 Persei. 7 Coron. e| Lyre.
Castor. ° Bootis. e? Lyre.

¢ Cancri. 49 Serpentis. ¢ Sagitte.

w Leonis. o Corone. 61 Cygni.

y Leonis. wu Draconis. d Equulei.

& Urse. 70 Ophiuchi. ¢ Aquarii.

Among these the most remarkable of his conclusions refer to
Castor, @ Cancri, ¢ Urse, y Virginis, and y Coron. In the cases
of Castor and y Virginis, he is enabled, by the kindness of Pro-
fessor Rigaud, to produce observations of their positions by Bradley
and Pound, which are peculiarly valuable, as they carry back the
history of these stars upwards of a century, and enable us to forma
much better judgement than heretofore of their orbits, both which
appear to be ellipses of considerable elongation. He describes a
very ready and easy graphical process by which these orbits may
be approximately laid down, and exemplifies it on y Virginis, re-
specting which he concludes that the present approach of the stars,
and increase of their angular velocity, will still go on for several
years, until their distance is reduced to less than a single second,
which, considering the brightness of both individuals, will render
this asingle star to all but the very finest telescopes. Castor he also
considers likely, ere very many years have elapsed, to become a
close double star, and again to open to a much more considerable
distance than at present.

In the case of 2 Cancri, he is led by his observations to conclude
that the motion is retrograde instead of direct, and much more
rapid, so that this star has nearly completed a whole revolution.
This conclusion is fully confirmed by his observations of the present
spring (1831), and also by the observations of Mr. Dawes, which
have been communicated to him very recently, and which agree in
a very remarkable manner with his own, and actually suffice to
trace the bimestral motion of the star, as had been previously done
in the case of § Urse. 7 Corone, too, offers, if all the observations
can be trusted, a still more remarkable instance of quick rotation,
being already considerably advanced in its second revolution since
Sir Wm. Herschel’s first discovery of it; but this will require further
confirmation, owing to the extreme difficulty of the ee

e

Astronomical Society. 445

The periods of these two stars may be stated respectively at 55 and
43 years; that of £ Urse at 562, which last determination agrees
nearly with that of M. Savary, who has assigned 58% years for this
element. The period of 70 Ophiuchi has been determined by Pro-
fessor Encke at 73°862 years.

Lastly, Mr. Herschel subjoins some practical remarks on the
management and action of telescopes, and takes occasion to intro-
duce a set of measures of the positions of Saturn’s satellites, taken
under remarkably favourable circumstances, and also a single ob-
servation of the place of the comet of 1830, the only one he could
succeed in procuring.

In a subsequent letter received from Mr. Herschel, he alludes to
a new method of taking the angles of position, viz., by reflected as
well as by direct vision. He conceives that this method possesses
two capital advantages: Ist, That the quantity directly measured
is double the quantity sought, by which, of course, the error of de-
termination is halved; and, 2ndly, That the error of the zero is
destroyed altogether, the double are being given by the difference
of readings in the limb of one and the same circle, maintained in one
and the same position. Mr. Herschel also adds, that subsequent
and very satisfactory measures of 4 Corone fully confirm the con-
clusion above mentioned with regard to the revolution of that star.

IV. On the dependence of a clock’s rate on the height of the
barometer, by the Rev. Dr. Robinson.

The rate of a clock of good workmanship may be assumed to
depend on three things ; first, the rate at a given temperature and
barometric pressure :. secondly, on the variation of temperature, as
shown by the thermometer; and thirdly, upon the atmospheric
pressure, measured by the barometer. The variation of temperature
not only affects the materials of the pendulum, but, along with the
atmospheric pressure, greatly modifies the action of the air in the
way of buoyancy and inertia, &c. Possibly, the irregular action of
the wheelwork, the diminution of arc from the thickening of the
oil on the pallets, and even the hygrometric state of the air, may
sensibly alter the rate of a clock; but the present memoir is confined
to the consideration of the first-mentioned sources of error.

As the changes are minute, Dr. Robinson formed equations of
condition, where the quantities sought were the rate of the clock at
49° of the thermomer, and 29°5 inches of the barometer, and the
retardations corresponding to a rise of 1° and 1 inch in each of these
instruments respectively. The absolute gain or loss of the clock
was determined with the utmost care.

“A thermometer placed in the clock-case, with its bulb three
inches before the pendulum rod, and on a level with the cover of
the jar, and a barometer with its cistern at the same level, were
noted morning and evening at half-past nine; a time chosen, not
merely as likely to give mean results for the whole day, but also
because it nearly bisects the average period of evening observations.
The thermometer was read through a square of plate glass, cemented

in

446 Astronomical Society.

in the door of the case; and this being screwed close, (as described
in the Armagh Observations for 1828,) all free communication with
the air is precluded, and the changes of temperature within it are
slower and more regular than would be possible in clocks of the
ordinary construction. This made observations at other than the
stated periods unnecessary. The barometer was observed whenever
its movements seemed irregular, and the mean for the day corrected,
if necessary, by interpolation.”

Dr. Robinson then shows that the equations, when treated by the
method of least squares, give, fur the gaining rate of the clock at
the standard temperature and pressure, 0°,263; for the gain by an
increase of 1° in the temperature (his clock was over compensated),
0°,069; and for the gain by a depression of 1 inch in the barometer,
0°,241. As the mere effect of the air's buoyancy on the mercurial
pendulum is 0°,15 for a change of 1 inch in the barometer, the re-
mainder is due to the inertia of the air carried along with the pen-
dulum in its oscillations.

Dr. Robinson finds that the barometrical pressure has no sensible
effect upon the arc of vibration, and, consequently, does not affect
the clock through this cause.

With respect to the barometric variation of rate, having once
determined its co-efficient, nothing is easier than to allow for it
when any sudden change occurs: it may, however, be corrected
mechanically with the utmost facility. A rise in the barometer
tends to make a clock go slower. Suppose a syphon barometer to
be attached to the pendulum, then a rise in the barometer will
transfer a portion of the mercury in the syphon to the tube, and
the effect will be the same as if a small weight were shifted from the
syphon end to the tube end of the barometer. Now if the syphon
be so adjusted to the pendulum, as to bore and situation, that this
alteration of the mercury in the barometer will accelerate the rate
as much as the increase of the air’s buoyancy and inertia retard it,
the clock will be unaffected by any variation of the atmospheric

ressure.

Dr. Robinson shows how the syphon barometers (he places two,
one on each side of the pendulum rod) may be constructed and
adjusted for any particular case.

«I had previously recognised the influence of the barometer on
the clock before the mercurial pendulum was applied; and, without
employing the method of minimum squares, satisfied myself that
the effect was even greater, being nearly 0°3 for an inch. In
examining this point for any given clock, it is however to be
remembered, that it is always necessary to make the probable
errors of observation considerably less than the quantity sought;
otherwise, no conclusive result can be obtained. This may be done,
either by taking the rate for intervals of several days, or by observ-
ing several stars on each night.”

A List

Zoological Society.

the Royal Observatory, Greenwich,

Spica Virg .
) 2L
.| Spica Virg.
>) 2L

4.}11]1 Tauri

>) 1L
N Tauri

1L
G Geminor.
(281)

HS veg fae
g Geminor.

hm s
13 17 6,08
14 2 43,42

13.17 6,94
14 50 2,08

15 34,20
24 33,76
38 35,46
54 27,40

27 32,76
1 7,24
8 53,34
5 6,04

7

5
5
5
5
6
6
6
6
7
7

Feb. 26.| 48 Leonis

o! Sextantis
o Bas

> 2L

>) 1L
a Cancri

.|(50) Leonis

oo

B Virginis

447

A List of Stars observed with the Moon, in the present year, at

13 22,98

24 42,42
35 40,74

18 27,40
28 2,80

(174) 36 25,84
| 1 6 Scorpii | 1
x 2h ]
Antares 1

11 17,78
29 20,18
41 23,18
53 6,26

4
4
5
30 6,74
3
5
.| a Virginis
2
HI Fa oy
h? Tauri
.| 23 Libre 22 29,04
y—— 15 27 24,72
1L 15 41 37,50

(The following information respecting this list is given in the Monthly
Notices of the Society, Vol. If. p. 42. “ N.B. The Astronomer Royal having
kindly offered to furnish the Society, from time to time, with the observa-
tions of moon-culminating stars made at Greenwich, the first series is here
given for the present year; and they will be continued in the subsequent
Monthly Notices, as they are received; by which means they will become
more speedily accessible to those persons who are desirous of making com~-
parisons of this kind.” |

ZOOLOGICAL SOCIETY.

August 9, 1831. Dr. Horsfield in the Chair.

A letter from George Swinton, Esq., of Calcutta, Corr. Memb.
Z.§., addressed to the Secretary, was read, announcing the trans-
mission to England, asa present to the Society, of an entire Dugong,
preserved in spirit and brine, which he hoped would arrive in a suffi-
ciently perfect state to admit of its dissection.

Specimens of two species of Bats, presented to the Society with
a numerous and valuable collection of birds formed at Madras by
Josiah Marshall Heath, Esq., F.L. & Z.S., were exhibited, and Dr.
Horsfield identified them as the Megaderma Lyra, Geoff., and a new

species

448 Roological Society.

species of the genus Nycticeyus, Rafin. He pointed out in the
former some discrepancies in the colouring from that described by
M. Geoffroy Saint-Hilaire, apparently from a specimen preserved in
spirit ; the individual before the Meeting agreeing much more nearly
with the colours as recently described by M. Isidore Geoffroy Saint-
Hilaire, from whose description it scarcely differed, except in the
less intensity of the rufous tinge of the tips of the hairs of the upper
surface.

Of the Nycticejus two specimens were exhibited, on which Dr.
Horsfield pointed out the characters by which that group had been
generically distinguished from Vespertilio as circumscribed by modern
authors. He remarked on the geographical distribution of the genus,
which might be regarded altogether as an American form, were it not
for the existence of 1 species in Java described by him in his ‘ Zoo-
logical Researches’ as the Vespertilio Temminckii, and of the present
species obtained on the Continent of India. As the second Indian
species of this group, he regarded the present acquisition as peculiarly
interesting. {t is considerablylarger than the Javanese species, from
which it differs also remarkably in its colouring.

Dr. Horsfield thus characterized and described the species :

Nycricesus Hearn. Nyct. capite cuneato supra lateribusque

planis, auriculis capite brevioribus oblongis rotundatis margine ex-
teriore parum eucisis trago elongato falcato, vellere pilis sericatis
brevissimis, not@o fusco, gastr@o ta

Long. corporis (cauda inclusa), 6 unc. + expansio extremitatum
anteriorum, 18 unc.

The head is of moderate length, nearly even above and compressed
at the sides. The muzzle is broad and abruptly terminated. The
nose is slightly emarginate. The eyes ———-. The mouth is propor-
tionally small. The lips are not rugose, and are nearly covered with
delicate hairs. ‘The ears are shorter than the head; the auricle ob-
long, erect, rounded, naked and slightly indented posteriorly, termi-
nating below in a small lobule ; the tragus linear, erect, falciform,
and shorter than the auricle.

The animal is uniformly and thickly covered by a short, very soft,
delicate silky hair, closely applied to the skin: this hair is about a
line in length on the back, but shorter and more delicate on the head ;
on the breast it is somewhat longer and downy. The colour of the
body and hair above is brown with a tawny hue ; underneath fulvous
with a slight tendency to gray ; the tint being uniformly distributed
over the throat, breast, abdomen and sides. The transparent mem-
brane is uniformly brown.

The collection of Birds formed by Major James Franklin, F.R.S.
&c., on the banks of the Ganges and in the mountain chain of Upper
Hindoostan, and presented to the Society by the Physical Committee
of the Asiatic Society of Calcutta, (which had been laid on the table
on the 23rd November last,) was again exhibited. The exhibition
had been conimenced at the previous Meeting of the Committee,
when the Raptorial and Insessorial Birds were brought under the
notice of the Members present ; and it was now concluded by the

Rasorial,

Zoological Society. 449

Rasorial, Wading, and Swimming Birds. On the former occasion, Mr.
Vigors, and on the latter, Mr. Yarrell, availed themselves of the op-
portunity to remark on the geographical distribution of many of the
species contained in the collection, and on other points connected
with their history. ‘They were exhibited in the order of the following

Catalogue of Birds (systematically arranged) which were collected on
the Ganges between Calcutta and Benares, and in the Vindhyian
hills between the latter place and Gurrah Mundela, on the Ner-
budda, by Major James Franklin, F.R.S. &c.

Orvo I. RAPTORES.
Fam. Farconiwa.
Sub-Fam. Aquilina—Genus Aquila.

1, Aquina Vinput1ana. Ag. pallidé brunneo variegata ; capite, pec-
tore, remigibus secundariis, cauddque saturatioribus, hujus apice
albido graciliter marginato ; remigibus primariis nigris ; capitis col-
lique plumis pallido-rufo lanceolatis.

Longitudo 26 unc.
Cawnpoor Eagle, Lath. ?

Sub-Fam. Falconina.—Genus Falco.
2. Falco Subbuteo, Linn. Hobby, Penn. Le Hobereau, Buff.
3. Falco Chicquera, Daud. Chicquera Falcon, Lath. Le Chicquera,
Le Vaill.
4, Falco Tinnunculus, Linn. Kestril, Penn. La Cresserelle, Buff.

Sub-Fam. Buteonina.—Genus Buteo.

5. Buteo Bacha. Falco Bacha, Daud. Bacha Falcon, Lath. Le
Bacha, Le Vaili.

Genus Circus.

6. Circus Teesa. Cire. capite corporeque rufo-brunneis, plumarum
rhachibus fuscis; dorso imo, rectricibusque ferrugineis, his fasciis
subobsoletis fuscis septem circiter notatis; remigum tectricibus
abdomineque albescenti notatis; femorum tectricibus crissoque
rufescenti-albis ; fronte, guld, nucheque fascid gracili albis ; ros-
tro pedibusque flavis, illius apice nigro.

Longitudo 17+.
Zuggun Falcon, Lath. ?

7. Circus cyaneus, Falco cyaneus, Linn. Hen Harrier, Penn.

8. Circus melanoleucus. Falco melanoleucus,Gmel. Black and white
Indian Falcon, Penn. Le Tchoug, Le Vaill.

9. Circus rufus, Briss. Moor Buzzard, Penn. Le Busard, Buff.

Sub-Fam. Milvina—Genus Elanus, Savigny.

10. Elanus Melanopterus, Leach. Le Blac, Le Vaill.

Fam, Strigide.—Genus Otus.

1]. Orus Bencarensis. Ot. pallide rufescens, fusco alboque undu-
latim variegatus ; nuche pectorisque plumis in medio strigaé
lata brunneo-nigra notatis ; abdomine fusco graciliter fasciato ;
remigibus rectricibusque lateralibus prope apicem brunneo fas-
cialis, his mediis per totam longitudinem similiter notatis.

N.S. Vol. 10. No. 60. Dec. 1831. 3M Longitudo

450 Soological Society.

12

13
14

15
16

17

18
19

20

21

22
23

24

Longitudo 20.
Dr. Latham alludes to this as a variety of the great-eared Owl.
Genus Noctua.

- Nocrva Inpica. oct. cinereo-brunnea; capite guttis parvis
albis, alis grandioribus notatis; abdomine albo, maculis brunneis
lunulatis notato ; remigibus rectricibusque albo fasciatis ; re-
gione circumoculari, gula, fascidque subgulari ad aures exten-
dente albis.

Foem. magis rufescens, abdomine magis fasciatim maculate.
Longitudo 9.
Indian Spotted Owl, Lath. ?

Orvo II. INSESSORES.
Tribus Fisstrostres,
Fam. Meropide.—Genus Merops.

. Merops Philippinus, Linn. Philippine Bee-eater, Lath. Grand
Guépier des Philippines, Buff.

. Merops viridis, Linn. Indian Bee-eater, Lath. Guépier a collier
de Madagascar, Buff.

Fam. Hirundinide.—Genus Hirundo.

. Hirundo Klecho, Horsf. Klecho Swallow, Lath. Hirondelle lon-
gipenne, Temm.

. Hirunpo Fiticaupata. Hir. supra purpurascenti-atra, remigi-
bus fuscis ; corpore subtiés maculisque rectricum omnium late-
ralium albis ; capitis vertice rufo ; rectrice utrinque laterali elon-
gato, ad apicem gracillimo.

Statura Hir. riparie.
Wire-tailed Swallow, Lath.
- Hirundo riparia, Linn. Sand Martin, Penn. L’Hirondelle de
rivage, Buff.
Genus Cypselus.
. Cypselus affinis, Hardw. Allied Swift, Hardw.
. Cypselus Palmarum, Hardw. Balassian Swift, Lath.
Fam. Caprimulgide.—Genus Caprimulgus.

. CaprimuLeus monricotus. Cap. pallidé cinereo-brunneo, rufo,
fuscoque sparsim variegatus; abdomine rufescenti-fusco fasci-
ato; remigibus secundariis rufo nigroque fasciatis, primariis
brunnescenti-nigris, quatuor externis fascid lata alba in medio
notatis ; rectricibus sex mediis fasciis gracilibus nigris undu-
latis, duabus utrinque lateralibus albis apicibus brunneis.
Foem. fascid alarum rufa; caudé concolori (sine albo).
Longitudo 10.

Great Bombay Goatsucker, Lath.?
. Caprimulgus Asiaticus, Lath., Ind. Orn. Bombay Goatsucker,
Lath.
Fam. Halcyonida.—Genus Alcedo.
. Alcedo Bengalensis,Gmel. Little Indian Kingsfisher, Edw.
. Alcedo rudis, Linn, Black and white Kingsfisher, Edw.

Genus Halcyon.
. Halcyon Smyrnensis. Alcedo Smyrnensis, Linn. Smyrna Kings-
Jisher, Lath. Martin pécheur de la céte de Malabar, Buff.
Tribus

Zoological Society. 451

Tribus DenrTIRosTREs.
Fam. Muscicapide.—Genus Muscicapa.
25. Muscicapa Banyumas, Horsf. Banyumas Flycatcher, Lath. Gobe-
mouche Chanteur, Temm.
26. Muscicapa nitida, Lath., Ind. Orn. Nitid Flycatcher, Lath.

Genus Muscipeta.
27. Muscipeta Paradisi. Muscicapa Paradisi, Linn. Paradise Fly-
catcher, Lath. Gobe-mouche Tchitrec-be, roux et blanc, LeVaill.
28. Muscipeta peregrina. Parus peregrinus, Gmel. Crimson-rumped
Flycatcher, Lath. Gobe-mouche Oranor, Le Vaill.

Genus Rhipidura.

29. Ruipmpura auporrontata. Rhip. capite collogue nigris; dorso
cinereo-nigro ; alis cauddque fusco-nigris ; fascia subgracili
frontali super oculos ad nucham extendente, pectore, abdo-
mine, maculis tectricum alarum, apicibusque rectricum, duabus
mediis exceptis, albis.

Longitudo 6.
White-browed Flycatcher, Lath. ?

30. Ruiripura Fuscoventris. Rhip. capite nigro; dorso abdomine-
que cinereo-nigris ; alis cauddque fusco-nigris ; strigd brevi su-
perciliari colloque in fronte albis; rectricum trium lateralium
apicibus albescentibus.

Longitudo 73.
Broad-tailed Flycatcher, Lath. ?
Fam. Laniade.—Genus Ocypterus.

31. Ocypterus leucorhynchus. Lanius leucorhynchus, Linn. White-
billed Shrike, Lath. Pie-griéche de Manille, Buff.

Genus Edolius.

32. Edolius cerulescens. Lanius cerulescens, Linn. Fork-tailed

Indian Butcher-bird, Edw. :
Geaus Lanius.

33. Lanius muscicapoipes. Lan. brunnescenti-cinereus subtus albes-
cens; strigd superciliari rufescenti-alba ; alis rectricibusque
fusco-brunneis, his duabus lateralibus albis basi notdque ad api-
cem fusco-brunneis.

Foem. aut Mas jin. capite corporeque supra albido maculatis.
Longitudo 6.
Keroula Shrike, Lath. ?

Genus Collurio.

34. Collurio Excubitor. Lanius Excubitor, var. Linn, Cinereous
Shrike, var. C. Lath.

35. Collurio erythronotus, Proceed. Zool. Soc. p. 42. Grey-backed
Shrike, Lath. ?

36. Cotivrio niGRicers. Col. capite supra, nuchd, alis, cauddque
nigris ; guld, pectore, abdomine medio, maculdque in medio
alarum, albis; dorso cinereo ; scapularibus, uropygio, abdo-
minis lateribus, crissoque rufis.

Longitudo 84.
Indian Shrike, Lath, ?
3M2 Collurio

452 Zoological Society.

37. Collurio Hardwickii, Proceed. Zool. Soc. p. 42. Bay-backed
Shrike, Lath. ?
Genus Graucalus.
38. Graucalus Papuensis, Cuv. Corvus Papuensis, Gmel. Papuan
Crow, Lath.
Genus Ceblepyris.
39. Ceblepyris cana, Temm. Muscicapa cana, Gmel. Ash-coloured
Flycatcher, Lath.
40. Ceblepyris fimbriatus, Temm. LEchenilleur frangé, Temm.
Fam. Merulide.—Genus Pitta.
41. Pitta brachyura. Corvus brachyurus, Linn. Short-tailed Crow,
var. B. Lath. Short-tailed Pie, Edw.

Genus Oriolus.

42. Oriolus Galbula, Linn. Golden Oriole, Lath. Le Loriot, Buff.

43. Oriolus melanocephalus, Linn. Black-headed Oriole, Lath. Loriot
de la Chine, Buff.

44, Orrtotus Maperaspatanus. Or. fronte, corpore supra, tectrici-
bus alarum, abdomineque luteis ; capite supra, genis, remigibus,
notdque mediand rectricum fusco-atris; guld alba striis fusco-
atris.

Longitudo 9.
Oriolus Galbula, var. y. Lath. Yeliow Indian Starling, Edw.
Yellow Starling from Bengal, Albin.

Genus Turdus.

45. Turdus macrourus, Gmel. Long-tailed Thrush, Lath.

46. Turdus Saularis. Gracula Saularis, Linn, Pastor Saularis,
Temm. Little Indian Pie, Edw.

Genus Timalia.

47, Timauia Cuaranma. Tim. supra pallidé brunnescenti-, subtiis rufes-
centi-cinerea ; capite corporeque supra lineis fuscis striatis ;
rectricibus fusco obsolete fasciatis ; rostro pallido.

Longitudo 93.
Gogoye Thrush, Lath. ?

48. Timalia pileata, Horsf. Pileated Thrush, Lath.

49, TimaLiaA uypoteuca. Tim. supra rufescenti-brunnea, subtis alba ;
alis rufis ; his caudéque subtis cinereis, rectricibus fusco obsoleté
fasciatis ; rostro nigro.

Longitudo 63.

50. Trmaia nyPeRYTHRA. Tim. supra olivascenti-brunnea; capite in
Sronte corporeque toto subtis rufis ; caudd superne fusco obsoleté
fasciata ; rostro pallido.

Longitudo 5.
Genus Ixos.

51. Ixos jocosus. Lanius jocosus, Linn. Jocose Shrike, Lath.

52. Ixos Cafer. Turdus Cafer, Linn. Cape Thrush, Lath. Le Cou.
rouge, Le Vaill.

53. Ixos fulicata. Motacilla fulicata, Linn. Sooty Warbler, var. Lath,
Traquet noir des Philippines, Buff.

Fam. Sylviade.—Genus Tora.

54. Jora scapularis, Horsf. Scapular Wagtail, Lath.

Genus

Zoological Socrety. 4.53

Genus Sylvia.

55. Sylvia Hippolais, Lath. Ind. Orn. Lesser Pettichaps, Lath. Reed
Wren, Lath.

This is the bird alluded to under Dr. Latham’s Reed Wren, as an
Indian variety called Tickra and Ticktickee.
Genus Prinia.

56. PRINIA CURSITANS. Prin. corpore supra pallidé brunneo, fusco
striato; guld jugulogue albis ; abdomine rufescente ; rectricibus
mediis fuscis, omnibus subtis ad apicem fascia nigra albo termi-
nata notatis.

Longitudo 4.

57, PRINIA MACROURA. Prin. supra grisescenti-brunnea ; capite, alis,
uropygioque subrufescenti tinctis ; subtus ferrugineo-albida 3 Tec-
tricibus quatuor mediis saturatioribus fusco obsolete fasciatis,
subtis ad apicem fusco leviter notatis.

Longitudo 53.

58, PriniA GRACILIS. Prin. cinereo-grisea ; dorso, alis, cauda@que
olivascentibus ; gula, pectore, ablomineque subtis albidis; rec-
tricibus subtus griseis fascid nigra albo terminatd notatis.
Longitudo 44.

Foodkey Warbler, Lath. ?
Genus Motacilla.

59. Moractuxa picata. Mot. capite, collo, corporeque supra nigris ;
strigd utrinque superciliart alterdque longitudinali alarum, cor-
pore subtiis, rectricibusque duabus lateralibus albis.

Longitudo 9.
Pied Wagtail, Lath. pl. 104.

60. Motacilla flava, Linn. Bergeronnette jaune, Buft., & Bergeronnette
de printemps, Buff. Yellow Wagtail, Lath.

This is the Indian bird alluded to by Dr. Latham under the head of
Yellow Wagtail, called Peeluck, which is its Indian name.

Genus Sazicola.
61. Saxicola rubicola, Temm. Stone Chat Warbler, Lath.
Genus Phenicura.
62. Phenicura atrata, Jard. & Selb. Indian Redstart, lid.
Fam. Pipride.—Genus Parus.
63. Parus atriceps, Horsf. Mésange cap-négre, Temm.
Tribus ConrrostTREs.
Fam. Fringillide.—Genus Alauda.

64. Araupa Caenpooua, Al. supra pallidé grisescenti-brunnea,
plumis fusco in medio notatis ; corpore subtis strigdque superci-
liari albis ; rectricibus brunneis, duarum utrinque lateralium po-
goniis externis albis ; pectore brunneo maculato, capite cristato,
Statura Al, arvensis, Linn.

65. Araupa Guueuta. AL. pallide rufescenti-brunnea, plumis in
medio late et intense brunneo lineatis; subtius albescens, pectore
brunneo lineato ; femoribus rufescent ibus ; rectricibus brunneis,
externa utrinque fere totd, secunde pogonio externd, albis.

Statura feré pracedentis.
Genus

454 Zoological Society.

Genus Mirafra.

66. Mirafra Javanica, Horsf. Alouette mirafre, Temm.

67. Mirarra pHenicura. Mir. pallidé cinereo-brunnea ; corpore sub-
tis, remigum pogoniis internis, rectricumque basi rufis ; rostro
albo, culmine apiceque fuscis.

Longitudo 5.
Genus Emberiza.

68. Emberizu Baghaira. Baag-geyra Lark, Lath.

This bird is the common Oréolan of India, called Baghairi,

69. Emberiza Gingica, Gmel. Duree Finch, Lath.

70. Emberiza cristata, Gould’s Century of Himalayan Birds.

71. Emberiza Bengalensis. Baya Berbera, Asiat. Res. Loxia Benga-
lensis, Linn.

The Hindu name of this bird is Baya ; its Sanscrit name Berbera.
Genus Fringilla.

72. Fringilla Amandava, Linn. Le Bengali Piqueté, Buff.

73. Fringilla formosa, Lath. Lovely Finch, Lath.

74, Fringilla Malabaria, Loavia Malabaria, Linn. Malabar

Grosbeak, Lath.

75, FRINGILLA FLAVICOLLIS. Fring. supra cinereo-grisea, subtis
albida; jugulo maculd flava notato; humeris ferrugineis ; alis
maculis albis fascias duas exhibeniibus notatis.

Longitudo 5-35.
This bird, though placed amongst the Finches, differs in the form
of its bill, and it may perhaps hereafter be found expedient to re-
move it.

Genus Ploceus.

76. Ploceus Philippinus, Cuv. Philippine Grosbeak, Lath.
Fam. Sturnide.—Genus Pastor.
77. Pastor roseus, Temm. Rose-coloured Thrush, Lath. Le Roselin,
Le Vaill.
78. Pastor tristis, Temm. Merle des Philippines, Buff.
79. Pastor griseus, Horsf. Le Martin gris de fer, Le Vaill.
80. Pastor Contra vel Capensis, Temm. Etouwrneau Pie, Buff.
81. Pastor Pagodarum,Temm. Le Martin Brame, Le Vaill.
Fam. Corvide.—Genus Corvus.
82. Corvus Corone, Linn. Carrion Crow, Lath.

This bird appears to be the common Carrion Crow of India; it
differs only in size from the European Crow, and in the greater
elevation of the bill.

Genus Coracias.
83. Coracias Bengalensis, Linn. Blue Jay from the East Indies, Edw
Genus Pica.
84. Pica vagabunda, Wagler. Rufous Magpie, Hardw.
Fam. Buceride.—Genus Buceros.
85. Buceros Gingianus, Lath. Indian Hornbill, Lath.

There is some confusion with regard to this bird in Dr. Latham’s
General History, under the heads of Gingi and Indian Horn-
bill: it is the Dhanesa of India,

86, Buceros Malabaricus,Gmel. Unicorn Hornbill, Lath.
There

Zoological Society. 455

There is also much confusicn with regard to this bird under the
heads of pied Hornbill and Unicorn Hornbill of Latham: it is
the Dhanesa of the latter, var. B.

Tribus Scansores.
Fam. Psittacide.—Genus Paleornis.

87. Palzornis torquatus, Vig. Psittaca Borbonica torquata, Briss. La
Perruche @ double collier, Buff.

88. Palzornis Bengalensis, Vig. Psittacus Bengalensis,Gmel. Blos-
som-headed Parakeet, Lath. sp. 74. var. A.

89. Patzornis FLAVICOLLARIS. Pal. viridis; capite lilacino-cano,
flavo marginato ; rectricibus mediis ceruleis apice albo.
Longitudo 12.

According to the description, this would appear to be Dr. Latham’s
yellow-collared Parrakeet ; but he refers to figures which do not
correspond.

Fam. Picide.—Genus Bucco.

90. Bucco canicers. Buc. gramineo-viridis ; capite, nuchd, collo,
pectoreque griseis ; illius plumis in medio albido lineatis ; rostro
rubro ; pedibus flavis; regione circumoculari nudd flavescenti-
rubra.

Longitudo 10.
Fichtel’s Barbet, Lath. ?

This bird is the Bura-Bussunta of India, and appears to be the
same as var. A. of Dr. Latham’s Fichtel’s Barbet.

91. Bucco Philippinensis,Gmel. Barbu des Philippines, Buff.

Genus Picus.
92. Picus Bengalensis, Linn. Bengal Woodpecker, Lath.
93. Picus Mahrattensis, Lath., Ind. Orn. Mahratta Woodpecker, Lath.

Fam. Certhiade.—Genus Sitta.

94. SirTa CASTANEOVENTRIS. Sit. superné griseo-plumbea ; pectore
abdomineque castaneis ; strigd a rictu per oculos ad nucham ex-
tendente, remigibus, rectricumque pogoniis internis nigris ; guld
macula que rectricum lateralium albis.

Longitudo 5.
Ferruginous-bellied Nuthatch, Lath. ?

Genus Certhia.

95. Cerraia spttonora. Certh. supra griseo-fusca, albo maculata ;
capite albo graciliter striato; gula ubdomineque albidis, hoc
fusco fasciato ; caudé albo fuscoque fasciata.

Longitudo 53.
The tail of this bird is soft and flexible, in which respect it differs
from the type of the genus, but it agrees in all others.

Genus Upupa.
96. Upupa minor, Shaw. La Huppe d’ Afrique, Le Vaill.
Fam, Cuculide.—Genus Leptosomus.
97. Leptosomus Afer. Cuculus Afer, Gmel. Edolian Cuckow, Shaw.
Genus Cuculus.
98. Cuculus canorus, Linn. Common Cuckow, Lath.
This bird, on comparison with the common Cuckow, differs so little
that

456 Soological Society.

that it can scarcely be called a variety; it is the common Cuckow
of India, and its habits and note resemble those of the European
bird.

99. Cuculus fugax, Horsf. Bychan Cuckow, Lath.

The common Indian name of this bird is Pipiha or Pipeeha, from
its note ; in Sanscrit Chataca. Dr. Buchanan named it Cuculus
radiatus.

100. Cuculus Sonneratii, Ind.Orn.? Le petit Coucou des Indes, Sonn. ?
Sonnerat’s Cuckow, Lath. ?

Not having either specimen or figures to refer to, I conclude, from

description alone, that this bird is Sonnerat’s Cuckow.

Genus Centropus.

101. Centropus Philippensis, Cuv. Coucou des Philippines, Buff.
Chestnut Coucal, Lath.

This bird is the Mahooka of India, so named from its note; it is
called also, by the English, Pheasant Crow. Dr. Latham’s
chestnut Coucal very accurately describes it, but his figure is
bad; having apparently been taken from a drawing of Gen.
Hardwicke’s, which stated it to be a young bird. Dr. Buchanan
named it Cuculus castaneus.

Genus Eudynamys.

102. Eudynamys Orientalis. Cuculus Orientalis, Linn. Eastern black
Cuckow, Lath. Coucou noir des Indes & Coukeel, Buff.

This bird is the Coel of India, and the Coukeel of Buffon.

103. Eudynamys Sirkee, Centropus Sirkee, Hardw. Sirkeer Cuckow,
Lath.

Tribus TsnurrostREs.
Fam. Meliphagide.—Genus Chloropsis.

104. Chloropsis aurifrons, Jard. & Selby. Malabar Chloropsis, Jard.
& Selby.

This bird Le Huréwa of India, and is well described by Dr.
Latham as the Hurruwa Bee-eater.

Fam. Cinnyride.—Genus Cinnyris.

105. Crynyris Ortentauis. Cinn, capite, collo, dorsoque splendidée
virescenti-purpureis ; abdomine purpureo-atro; alis cauddque
atris; fasciculo utrinque sub alis aurantiaco.

Longitudo 4.
Eastern Creeper, Lath.

Orpo III. RASORES.
Fam. CotumsBip2.
Genus Vinago.
106. Vinago militaris. Columba militaris, Temm. Columbar Com-
mandeur, Temm. Hurrial Pigeon, Lath.
Genus Columba.
107. Columba tigrina, Temm. Colombe a nuque perlée, Temm.
108. Columba Cambayensis,Gmel. Colombe maillée, Yemm.
109. Columba risoria, Linn. Colombe Blonde, Temm. La Tour-
iterelle Blonde, Le Vaill.
Le Vaillant mentions a larger bird of this species which is common
in

Zoological Society. 457

in Africa ; the same thing occurs also in India, where there are
two birds differing only in size.
110. Columba humilis, Temm. Colombe terrestre, Temm.
Fam. PHASIANIDZ.
Genus Pavo.
111. Pavo cristatus, Linn. Le Paon, Buff. Crested Peacock, Lath.
Genus Tragopan.
112. Tragopan Satyrus, Cuv. Meleagris Satyrus, Linn. Horned
Pheasant, Lath.
Fam. TeTRAONID2.
Genus Pterocles.
113. Pterocles exustus, Temm. Ganga ventre-brulé, Temm.

Genus Francolinus.

114. Francolinus Ponticerianus, Temm. Francolin @ rabat, Temm.
115. Francolinus vulgaris, Steph. Le Francolin, Buff. Francolin, Edw.
Genus Perdiz.

116. Perdix picta, Jard. & Selby. Painted Partridge, lid. Beauti-
ful Partridge, Lath.

}17. Perdix Hardwickii, Gray. Curria Partridge, Lath.

118. Perdix Cambayensis, Temm. Perdrix rousse-gorge, Temm.

Genus Coturniz.
119. Coturnix dactylisonans, Meyer. Common Quail, Lath.
This bird is named Ghagul ; it corresponds with the European spe-
cies, and is not very common in India.
120. Coturnix Coromandelica. Perdix Coromandelica, Lath. Perdix
textilis, Temm. Caille natiée, Temm.
This is the most common Quail of India called Bhuteir. Dr. Bucha-
nan named it Perdix olivacea.
Genus Hemipodius.
121. Hemipodius Dussumier, Temm. Turnix Dussumier, Temm,
Mottled Quail, Lath.

Fam. StrurHsionipz.
Genus Olis.
122. Otis Indica, Ind. Orn.? White-chinned Bustard, Lath. ?

This bird has usually been considered as the female of the Otis
aurita, and has been so figured and described ; but it is well
known to be a distinct bird. It is the common Leek of India,
called by the English Bastard Florican. 1 am not quite certain
that Dr. Latham’s White-chinned Bustard is the bird, but his
description is so near, that [ have not thought it proper to make
a new species,

Orvo lV. GRALLATORES.
Fam. Gruipz.
Genus Grus.
123. Grus Orientalis, Briss. Ardea Antigone, Linn. Indian Crane, Lath.
Fam, Arprip®.
Genus Mycteria.
124. Mycteria Australis. Ciconia Mycteria Australis, Hardw. Tetaar
Jabiru, Lath.

N.S. Vol. 10. No. 60. Dec. 1831. 3N Genus

458 Zoological Society.

Genus Ardea.

125. Ardea purpurea, Linn. Le Héron pourpré huppé, Buff. Crested
Purple Heron, Lath.

126. Ardea speciosa, Horsf. Darter Heron, Lath.

This bird is without doubt the Darter Heron of Dr. Latham ; and
the Ardea speciosa of Dr. Horsfield is, I think, merely the Ja-
vanese type of the same bird.

127. Ardea Torra, Buch. Ardea Egretta, Lath. Ind. Orn. var. Ar-
dea alba, Linn. var. Great Egret, Lath. Indian variety Torra
or Bughletar.

This is the Indian White Egret, and it differs only in size from the
European species, being somewhat smaller. Dr. Buchanan
named it 4rd. Torra, and when without its filiform appendages
on the back, Ard. Putea; so that these Indian terms appear
to correspond with Ard. Egretia and Ard. alba.

128. Ardea Caboga, Penn. Caboga Heron, Penn. Gibraltar Heron,
Lath. var. A.

The term Caboga is acorruption of the Indian term Gao-buga, Cow
or Cattle Heron, in allusion to its frequently being seen amongst
cattle, like the Gibraltar Heron.

Genus Botaurus.

129. Botaurus cinnamoneus. Ardea cinnamonea, Gmel. Cinnamon
Heron, Lath.

Genus Nycticorax.

130. Nycticorax Europeus. Ardea Nycticorax, Linn. Night Heron,
Lath.

Genus Tantalus.
131. Tanialus papillosa. Ibis papillosa, Temm. Bald Ibis, Lath.

Fam. ScoLopacip&.
Genus Rhynchea.
132, Rhynchea Orientalis, Horsf. Cape Snipe, Lath, Bécassine de
Madagascar, Buff.
Genus Tringa.
133. Tringa ochropus, Linn. Green Sandpiper, Penn.
134, Tringa Glareola, Linn. Wood Sandpiper, Penn.
135. Tringa pusilla, Linn. Little Sandpiper, Lath.
136. Tringa hypoleucos, Linn. Common Sandpiper, Lath,
Fam. Rauuipz.
Genus Parra.
137. Parra pheenicura. Gallinula phenicura, Lath., Ind.Orn. Red-
tailed Gallinule, Lath. Poule-Sultane de la Chine, Buff.
138. Parra Sinensis, Gmel. Chinese Jacana, Lath.
139. Parra Indica, Lath., Ind. Orn. Indian Jacana, Lath.

Genus Rallus.
140. Rallus niger, GGmel. Black Rail, Lath.
Genus Porphyrio.
141, Porphyrio hyacinthinus. Fulica Porphyrio, Linn, Purple Water-

hen, Edw.
Fam.

Zoological Society. 459

Fam. CuarapRiaDz.
Genus Vanellus.

142, Vanellus Goensis. Tringa Goensis, Lath. Vanneau armé de Goa,
Buff.

143. Vanellus ventralis. Charadrius ventralis, Wagl. Spur-winged
Plover, Hardw.

144. Vanellus bilobus. Charadrius bilobus, Gmel. Bilobate Sand-
piper, Lath.

Genus Cursorius.

145, Cursorius Asiaticus, Gmel. & Lath. Courvite de la Céte de Co-
romandel, Buff.

Genus Himantopus.

146. Himantopus melanopterus. Charadrius Himantopus, Linn. L’
Echasse, Buff.

Genus Charadrius.

147. Cuaraprivs uiaticuLoipes. Char. supra griseo-fuscus ; fascid
frontali alterdque verticali, corpore subtus, collariqgue nuchali
albis ; lined sub oculis ad aures extendente, fascia ad frontem,
torqueque pectorali subgracili ad nucham extendente nigris ;
rectricibus, duabus mediis exceptis, albis, in medio nigro et
griseo-brunneo notatis, fasciam semilunarem exhibentibus.

This bird differs chiefly from the European species in size, being at
least one third smaller, and in the narrowness of the pectoral band.

Orpo V. NATATORES.

Fam. ANATIDZ.

Genus Anser.
148. Anser Indicus, Lath., Ind. Orn. Barred-headed Goose, Lath.
149. Anser melanotos, Gmel. Black-backed Goose, Lath.
150. Anser Coromandeliana, Gmel. Sarcelle de la Céte de Coroman-

del, Buff. Anas Girra, Hardw. Girra Teal, Lath.

Genus Anas.
151. Anas arcuata, Cuv. Siley Teal, Lath.

The name of this bird in India is Siley or Silhei, from its whistling
note ; the English call it whistling Teal ; it scarcely differs from
the Javanese species as figured by Dr. Horsfield.

152. Anas Crecca, Linn. Common Teal, Lath.
This bird is the common Teal of India, and agrees exactly with
the British species.
Fam. Cotympipa.
Genus Podiceps.
153. Podiceps minor, Lath., Ind. Orn. Little Grebe, Lath.
Fam. PELECANIDZ.
Genus Carbo.
154. Carbo fuscicollis. Phalacrocorax fuscicollis, Shaw. Brown-necked
Shag, Lath.
Genus Plotus.
155. Plotus melanogaster, Gmel. Black-bellied Darter, Lath.
Genus Slerna.
156, Sterna melanogastra, Temm. Hlirondelle de mer a ventre noir,
Temm.
3N 2 August

460 Roological Society.

August 23, 1831. Joseph Smith, Esq. in the Chair.

Two letters from Mr. J. B. Arnold of Guernsey were read, con-
taining particulars of his experiments in the naturalization of Sea
Fishes in a lake chiefly supplied with fresh water. The area of the
lake is about five acres ; its depth various ; and its bottom also va-
rious, being muddy, gravelly, and rocky. The water is during
nine months of the year drinkable for cattle, but in consequence of
a supply which it receives through a tunnel communicating with the
sea, is rather salt in sammer, at which season the freshes do not
come down so plentifully as at other times. The fishes introduced
into the lake have been the grey Mullet, Sole, Turbot, Brill, Plaice,
Basse, Smelt, and grey Loach. All of these have thriven well, and
are believed to have increased in numbers: the grey Mullet espe-
cially is known to have bred as freely as in the sea itself. A single
Whiting having been caught for three successive years, was found
to have grown considerably : a Pilchard also throve well. All the
above-mentioned fishes were placed ia the lake, except perhaps the
Brill; but others, as the silver Bream, appear to have introduced
themselves. It is even suspected that hybrid fishes have been pro-
duced, as several have been caught which were unknown to persons
well acquainted with the species usually met with on the coast of
Guernsey. Mr. Arnold adds that Sea Fishes, after having been
naturalized in his lake, have been transferred to ponds of spring
water, where they have not only lived, but done well; and that such
naturalized fishes have been carried to a long distance, being much
more tenacious of life than those caught in the sea.

Numerous specimens of Hylurgus Piniperda, Latr., presented to
the Society by Barlow Hoy, Esq., were exhibited, together with
specimens of the shoots of Pzxes perforated by these insects. The
mode in which the young branches are destroyed by these perfora-
tions has been illustrated by Mr. Lindley in Mr. Curtis’s ‘British
Entomology’. Its effect was regarded by Linnzus as analogous to
that of pruning.

The exhibition of the collection of Fishes formed at the Mauritius
by Mr. Telfair, portions of which had been brought before the Com-
mittee at the Meetings in April, was resumed. From among them
Mr. Bennett pointed out more particularly the following species

hich he believed to have been previously undescribed.

Serranus Detissiu. Serr. mazillis squamosis ; lobis pinne cau-
dalis elongatis, equalibus ; radio tertio pinne dorsalis producto :
superné stramineus, rubro cancellatim rivulatus, inferné lilacino-
ruber ; pinnis ventralibus aurantiaco-flavis.

D.+9. A. ;

Affinis, ut videtur, Serr. Borbonio, Cuv. et Val. Corpus altum, al-
titudo longitudinis (exclusa pinna caudali) dimidium zquans. Pinne
pectorales ventrales longitudine equantes. Preoperculi angulus
spina unicé magna armatus.

SERRANUS MITIS. Serr. mazillis alepidotis ; radio ultimo pinna-
rum dorsalis analisque elongato: corpore elongato: argenteus,
dorso obscuré flavo-brunneo ; pinnis flavo tinctis ; dorsali nigro
tenuiter submarginata.

Reo. vA: Serr.

Zoological Society. 461

Serr. filamentoso, Cuv. et Val., longior : corpus, prasertim ad hu-
meros, crassius: oculus major : vertex rugosus (in Serr. filamentoso
granulosus tantum): dentes antici superiores conici utrinque qua-
tuor debiliores (in Serr. filamentoso majores utrinque duo): color
pallidior, flavescens.

Serranus TELFAIRII. Serr. maxillis alepidotis ; radio ultimo

pinne dorsalis analisque elongatis : saturate roseus, dorso laté
citrino maculato, posticé albidus ; lateribus argenteo viltatis, gut-
tatimque conspersis ; pinna dorsali anticé citrind, basi roseo-, apice
niveo-maculatd.

D. +4. A- 3

Affinis, ut videtur, Serr. zonato, Cuy, et Val., quem numero ra-
diorum equat, cujusque formam, etiam pinnarum, emulat. Differt
pictura,’et presertim lateribus argenteo vittatis guttatisque.

The latter two species form an interesting addition to a section of
the genus Serranus distinguished by the elongation of the last ray
of both the dorsal and the anal fin. Two other species of this sec-
tion have been described by MM. Cuvier and Valenciennes, to whom
they have only very recently become known. Of one of these, Serr.
filamentosus, as well as of the two new species above described, spe-
cimens are contained in the Mauritius collection.

Diacore Ancutus. Diac. stramineo-flavescens, infra pallidior ;
wittis corporis utrinque septem lilacinis, supertoribus obliquis, infe-
rioribus longitudinalibus, 4ta 5tdque antice connexis angulum
acutum postopercularem formantibus ; pinne dorsalis parte mollz
superne tenuiter nigro marginata.

D.t. Awd.

Affinis, ut videtur, Dzac. duodecimlineata, Cuv. et Val.: numerus
radiorum idem, vittaeque haud operculum signant. Dentes maxille
superioris externi conici, distantes, subequales, duo anteriores an-
gulares solum majores ; maxille inferioris minores, tres laterales
medii utrinque majores.

Denrex LycoGEnts. Dent. macillistransversim dentato-cristatis :
dentibus conicis anticis sex, maxille inferioris lateralibus majort-
bus : plumbeus, wittis dorsalibus plurimis argenteis, ventralibus
distantibus fusco-flavis ; macula elongata argenteo-alba sub basi
postica pinne dorsalis ; pinnis ventralibus, pectoralibus, dorsalt
analique anticé rubris, caudali flavida.

+h. A.3.

DAscyLLus UNICOLOR. Dasc. corpore alto unicolore nigricante.
D.tt. A. +
Forma Dasc. marginati, Cuv. et Val.

Hetases axituanis. Hel. pallid? ceruleo-fuscus?; axilla nigra;
pinnis, presertim caudal analique, ceruleo-nigrescentibus.
D.44. A.-r

Affinis, ut videtur, Hel. anali, Cuv. et Val. Radius secundus pinnz
analis fortior, sequentes longitudine aliquantulum superans. Cor-
pus ovatum.,

Juuis Cuviert. Julis caudé subquadratd : pinne dorsalis radio

primo longissimo (quam tertius triplo longiore): rufescenti-brun-
neus

462 Loological Society.

neus ceruleo punctulatus ; capite virescente, vittis tribus latis
rufis ; pinnis dorsali analique luteis, sanguineo oblique lineatis,
nigro laté marginatis, ceruleoque fimbriatis ; hujus fascia margt-
nali lined ceruled longitudinali media alterdque ad basin notata.
Doyen. sr. OP. 125 eas.

This new species of Julis is one of those fishes, now becoming nu-
merous, which might be confounded with the Julzs Aygula, ( Coris
Aygula, LaCép.). The latter appears to have hitherto rested solely
on the figure and description preserved by Commerson, no specimen
of it having been referred to as existing in collections. A specimen
of that species has, however, recently been added to the Society's
Museum from a collection of fishes formed in India, and agrees well
with the figure published by LaCépéde, in the truncation or even
sublunation of its caudal fin, and in its general form; in its dried state
its colour is uniformly dull blackish brown. This specimen was ex-
hibited in illustration of the distinction between Julis Cuvier and
Julis Aygula, and also to show that the fish figured under the latter
name by Dr. Riippel differed in various particulars, especially in the
rounded form of its caudal fin, from the species indicated by LaCé-
péde. To M. Riippel’s fish, it was remarked, the name of Julis
Ruppelii might properly be applied.

ANGUILLA MauritiAna. Ang. mazilld superiore breviore, obtusd;
rostro complanato ; pinne dorsalis initio pectoralibus quam anala
propiore; lined laterali conspicud : dorso fusco pallidoque gutta-
tim marmorato, lineolisque nigrescentibus interteatis notato ; pin-
nis fusco nebulosis.
leet

Mr. Bennett availed himself of the opportunity afforded by the
exhibition of the several species of Pterois contained in the Mauri-
tius collection, to bring before the Committee a fish which he had
formerly regarded as the Pterois volitans, under which name it was
included in the catalogue of Sumatran fishes appended to the me-
moir of Sir T. Stamford Raffles. It formed part of the collection
presented to the Society by its founder and first President. It was
thus characterized:

Prerois Russet. Pter. gents spinosim late lineato-serratis ; osse
infra-orbitali antico preoperculoque inferné spinosissimis : cirris
parvis sex, nasali utringue duobusque infra-opercularibus : pinnis
pectoralibus caudalis basin attingentibus.

D.33. A.g. P.13.
Kodipungi. Russel, Coromandel Fishes, No. 133.

September 13, 1831. |W. Yarrell, Esq. in the Chair.

At the request of the Chairman the following notes of a dissection
of the Alligator Tortoise (Chelydra serpentina, Schweig.) were read
by Mr. Martin. They were illustrated by preparations of the sto-
mach ; of the iliwm and colon ; and of the cloaca, with the penis and
urinary bladders: a drawing of the latter was also exhibited ; and
a drawing of the throat, representing the esophagus and trachea in
their natural positions,

«The animal was a male, and most probably young : its ee

rom

-

Soological Society. 463

from the nose to the anus being | foot 11 inches, and from the anus
to the end of the tail G6 inches. The length of the carapace was 11+
inches, and its breadth, following the curve, | foot 1 inch.

“On the plastron being removed, and the scapule (which are united
to it by intervening muscles) being turned back, the heart, inclosed
in a peritoneal sac, was exposed; the scapula in their natural posi-
tion extending over it like an arch: next, and in the same cavity,
(for there was no division either by muscle or membrane, ) the liver
was seen, divided into two distinct portions, and stretching com-
pletely across from side to side: below the liver and occupying what
may be called the pelvic portion of the cavity, lay the intestines,
among which on the right side was seen the colon or commencement
of the large intestines enfolding the spleen.

«‘ The heart consisted of one ventricle and two auricles, the right
of which was the largest. The figure of the auricles was rounded,
each in magnitude equalled the ventricle: both auricles contained
coagulated blood. ‘The ventricle was in shape acuminate, of a red
colour, and firm and fleshy in structure. Its carnee columne@ were
strong, distinct, and numerous, but did not separate it into cells or
chambers.

«« The liver consisted of two lobes. The right lobe was divided
into two parts. On its inferior surface was situated the gall-bladder
buried in its substance and containing dull green bile: the duct
barely half an inch long. The edge of the left lobe of the liver co-
vered the stomach, which passing under it fitted an elongated furrow
in the thick part of the lobe, and was closely united to it by the peri-
toneum. The outer curvature of the stomach was placed in contact
with the parietes of the carapace. The texture of the liver was
soft and spongy, easily broken down, and pouring out an abundance
of dark green fluid, with which it was saturated. The gall duct en-
tered the duodenum 6 inches below the pylorus. The under surface
of the liver on the right side was connected to the duodenum, and
partially to the lung on the same side, by peritoneal attachments.

«On the liver being removed the course of the intestines was more
fully exposed. Beginning with the esophagus, which immediately
on proceeding from the pharynx becomes firm and muscular (the
fibres being longitudinal), we find it dipping down on the right side
of the neck, keeping a straight course, passing under the right cla-
vicle, then crossing below the great arch of the neck within the shell,
and passing under the right laryngeal branch to the cardiac portion
of the stomach; its length being 7 inches. The cardium passes over
the left laryngeal branch, The length of the stomach is 7+ inches;
the circumference of the thickest part 3 inches; gently narrowing
to the pylorus. Its texture was firm and muscular, especially at the
pyloric portion; and between the peritoneal and muscular coats
numerous small white points were observed, which on being cut into
were found to arise from the presence of minute worms, of three or
four lines in length, coiled up under the peritoneum.

« The small intestines were strong and thick: their length 3 feet
ll inches, ‘Their internal surface presented longitudinal ad At

their

464 Zoological Society.

their termination in the large intestines there appeared the rudiment
of a cecum.

«Encircled by a fold of the colon was situated the spleen, of a dark
red colour, and soft spongy structure, almost round in shape, and of
the size of a small egg: several tortuous veins proceeded from it,
and the veins and arteries of the mesentery in general were of the
same character.

«‘ The length of the large intestines was 1 foot’7 inches; the mus-
cular coat was particularly distinct; the villous smooth}; and several
black patches were observed on its surface, which exhibited great
vascularity.

«‘ The urinary bladder was double, or rather it might be said that
there were two bladders, lying on opposite sides of the rectum, and
adhering to the sides of the pelvis, each communicating by a distinct
opening into the commencement of the cloaca. Their size and shape
was that of a small pear: their texture very thin and fibrous, the
fibres being irregularly disposed.

“« The penis, 2+ inches long, lay concealed entirely within the
cloaca. It was grooved along its upper surface with the furrow usual
in the Tortoises, but instead of being free or disengaged, was
attached by a close union throughout its whole length on the under
side to the cloaca. The glans was acuminate, and full an inch from
the anus. From this union of the penis to the cloaca it is difficult to
conceive that it can ever be protruded externally, especially when
its distance from the external orifice of the cloaca is considered. The
duct of the right bladder, in length half an inch, was found to
terminate just above the furrow of the penis, while that of the left
opened an inch on one side of it.

«The testes were about the size of a pigeon’s egg, elongated, of a
bright ochre colour, and situated in the pelvic portion of the abdo-
minal cavity, one on each side of the vertebral column ; their struc-
ture was soft and somewhat granular. There were no suprarenal
capsules. Beneath the ¢estes lay the kidneys, large, irregular in
figure, glandular in structure, consisting of brain-like reduplications,
and dipping between the interstices of the three lowest ribs, (or
rudiments of ribs,) on each side of the vertebral column.

“ The palate was smooth, with slight transverse ruge ; the pha-
rynx wide, simply membranous, and capable of great extension;
the tongue a smooth cartilaginous point, at the base of which the
laryna opened by a very small simple rima. ‘There was no epiglottis;
but around the rima aslight fold of the membrane was just percep-
tible. The laryna crossing before the pharyna dipped down on the
left side of the neck, and passing under the left clavicle, divided into
two great branches, at about afoot from the rima: the right branch
passed before the esophagus, and immediately entered the right lobe
of the lungs; the left passed under the cardiac portion of the sto-
mach to the left lobe.

“The lungs consisted of two large and equal lobes, distinct, flat,
and dark red, extending from the upper edge of the carapace as far
as the pelvis, but not as in the Land Lortoises (the Indian and i

or

Intelligence and Miscellaneous Articles. 465

for example) attached to the whole inner surface of the shell ; their
attachment was by one of their edges only to the vertebral column,
and slightly to the liver. Their texture was firm, and their cells,
though large, were not so irregular as in the Testudo Graca.

« Between the lungs passed two singular muscles, retractors of
the head, long and slender, which arising one on each side by a ten-
dinous origin from the base of the cranium passed on each side of
the neck, and coming in contact below its great curve, ran together
down the vertebral column, and were inserted into its sides in the
spaces between the 6th and 7th and 7th and 8th ribs, each by two
distinct fleshy terminations.

‘«« The difference exhibited by this animal in the attachments and
conformation of the lungs from the family of Tortoises in general
indicates an approach, not merely in external configuration, but in
internal structure, to the Alligators. Nor, although it must be con-
fessed in a degree less striking, is this approach unevidenced by the
structure of the urinary crgans; the bladder in this species although
double is yet small, while its enormous volume in the Tortozses in
general is a singular feature in their construction: the diminution
of volume in this organ seems to afford another indication, not to be
overlooked, of an approach to the Saurian Reptiles.

*« The posterior zaves opened by two distinct orifices one quarter
of an inch from the commencement of the palate and three quarters
from the point of the beak: their course was obliquely upwards,
and the length of each canal to the external orifice just 1 inch.

“ The os hyoides consisted of an irregularly shaped body and four
arched bones or processes united to it by cartilage ; from the ante-
rior part of the body aspinous process partly cartilaginous proceeded
to support the rudiment of atongue. The anterior pair of arched
bones were connected to the base of the skull by muscles only;
the second pair terminated in a broad and flat extremity, and were
more abruptly curved: their use seems especially to support the
pharynx, and they were not connected to the skull. The first pair
were each 4 inches in length ; the second little more than 3 inches.

The rings of the /arynz were perfect ; the length of the laryngeal
branches 3 inches.”

LVIII. Intelligence and Miscellaneous Articles.

ON MUDARINE.
D—D*: DUNCAN has published in the Transactions of the Royal
Society of Edinburgh for the present year, an account of the
active principle of the bark of the root of the Calotropis Mudarii or
Mudar, which he kas called Mudarine. The bark of this root has
been highly esteemed among the natives of India as a specific for the
cure of cutaneous and various other diseases ; Dr. Duncan has found,
however, that it possesses no specific virtue, but that it is nevertheless
extremely valuable from its common medicinal properties, which cor-
respond both in kind and in degree with those of ipecacuanha,
To obtain mudarine, the powdered root is to be digested in cold
N.S. Vol. 10. No. 60, Dec. 1831, 30 rectified

466 Intelligence and Miscellaneous Articles.

rectified spirit ; when the greater part of the spirit has been distilled,
the solution becomes deeper coloured, but retains its transparency.
As the temperature declines, a white granular resin is deposited by
a species of crystallization ; the whole is then allowed to dry spon-
taneously, that all the resin may concrete ; the dry residuum is then
treated with water, which dissolves the coloured portion, and leaves
the resin untouched ; the solution contains mudarine.

By exposure to the air, it dries readily, forming a mass of a pale
brownish colour, perfectly transparent and homogeneous in appear-
ance, having no tendency to crystallize, but becoming full of cracks,
diverging from the centre, exceedingly brittle, and having no adhe-
sion to the capsule containing it, from which it peels off spontaneously.
It has no smell, and is intensely bitter, with a very peculiar nauseating
taste. It is exceedingly soluble in cold water, at the ordinary tem-
perature of the atmosphere. It is also soluble in alcohol, but the
power of this solvent is increased by raising the temperature. It is
insoluble in sulphuric ether, oil of turpentine, and olive oil.

It is in the solution in water, when nearly saturated, that the pecu-
liar property of mudarine is most easily exhibited.

At ordinary temperatures this solution is quite fluid and transpa-
rent. When heat is gradually applied, it suffers at 74° slight dimi-
nution of transparency and limpidity ; these changes increase with
the temperature, so that at 90° its transparency is nearly lost, and
it acquires the consistence of a tremulous jelly ; but if it be then suf-
fered to cool, it recovers in a day or two its original limpidity and
transparency. If, instead of withdrawing the heat when it has risen
to 90°, it be further increased, other changes occur ; at 95° it is fully
gelatinized, and now there appears to be a separation taking place
into two parts, a soft brownish coagulum and a liquid nearly colour-
less, not unlike the separation of the serum from the crassamentum
of the blood, as it spontaneously contracts. At 95° the coagulum
contracts in size, while the fluid increases in proportion ; at 130° it
seems to dissolve ; probably, however, it is only reduced in size by
contraction ; at 185° the coagulum is very small, and has a tenacious
pitchy consistency, and at 212° little further change occurs.

The alterations which in this state it undergoes on cooling are next
to be observed. At 140° the fluid is very turbid, the coagulum i is not
diminished, and is hard and brittle ; at 110° the fluid is less turbid,
the coagulum remarkably brittle, with a resinous fracture ; at 100°
the fluid is more transparent, with thin detached pellicles on the sur-
face. When cooled down even to the freezing temperature, the cva-
gulum remains unaltered, and very much resembles colophony ; but,
after the lapse of several days, it gradually liquefies in the portion of
fluid in contact with it, without passing through the intermediate
form of ajelly. The coagulum, when separated from the fluid, is a
transparent brown mass, exceedingly brittle, not deliquescent; frag-
ments angular, lustre resinous, taste bitter and nauseous, adhering
to the teeth.

In this state it seems at first not to be soluble in distilled water,
but after some days it is dissolved in it, with the same phenomena as

in

Intelligence and Miscellaneous Articles. 467

in the fluid from which it was separated by boiling, and the solution
has acquired its original properties. The dry mudarine is readily
soluble in rectified spirit, and is not precipitated from the alcoholic
solution by the addition of water. As long as any considerable por-
tion of spirit remains, it is not coagulated by increase of temperature ;
but on allowing the spirit to evaporate by exposure to the air, it re-
mains dissolved in water, and has re-acquired its original properties.

It would therefore seem that its tardy solubility, after being con-
tracted, is owing to the state of increased aggregation ; for when this
is removed by alcohol, its solubility is quickly restored. Mudarine
is also extracted by the action of cold water from the powder, but it
is not so easily separated from a gummy matter also dissolved, as
from the resin extracted along with it by rectified spirit. Its pre-
sence is, however, sufficiently demonstrated by the cold infusion gra-
dually losing its transparency as its temperature is increased, and in
this case it regains its former transparency, even after having been
subjected for some time to the boiling temperature.

We therefore see, that, in this instance a very active principle is
more readily dissolved by cold than by boiling water; and it is pro-
bable that there are other instances in which heat is improperly em-
ployed, with the view of extracting the active principles of vegetable
substances.

PREPARATION OF OXICHLORATE OF POTASH. BY M. SERULLAS.
When chlorate of potash is heated in a glass tube or a porcelain
crucible, it fuses, boils, and yields oxygen gas. When the fire is
properly managed, and after ebullition has taken place for a certain
period, the mass thickens, and a moment arrives at which no more
oxygen is given out without increasing the heat : if the operation be
then stopped, and the salt dissolved and filtered, a great quantity
of oxichlorate of potash is) obtained in small brilliant crystals; 40
parts of chlorate yielded in this way 17°5 of oxichlorate. It appears
from the experiments of M. Serullas, that chlorate of potash requires
a temperature higher than that of boiling mercury for its decompo-
sition, and the oxichlorate a temperature considerably greater.

The moment at which chlorate of potash is converted into oxichlo-
rate, is ascertained by occasionally putting a spatula into the salt,
and withdrawing a small portion of it. This is to be powdered, and
treated with a little muriatic acid; if it gives a yellow colour, then
some chlorate still remains unconverted.—<Ann. de Chim. et de Phys.
Mars 1831.

SEPARATION OF ANTIMONY AND TIN.

M. Gay-Lussac employs tin as a precipitant of the antimony, when
the mixed metals have been dissolved in muriatic acid, with a small
quantity of nitric acid; muriatic acid being in excess, the antimony
is deposited as a black powder, when the tin is immersed in the solu-
tion. It requires the application of a moderate heat to produce the
separation perfectly ; the antimony is to be washed, and dried on the
water bath, If the two metals are in solution, and their weight is

302 not

468 New Patents.

not known, one portion should be precipitated by zinc to give the
whole of both metals, and another portion by tin to give the quan-
tity of antimony.— Ann. de Chimie, xliv. 433.

—_———

WHITE’S EPHEMERIS.
To Richard Taylor, Esy. F.R.A.S. F.L.S. Sc.

My Dear Sir,

I sHALL be very greatly obliged if you will
allow me, through the medium of your extensively
circulated Magazine, to correct a vexatious blun-
der which occurs in White’s Ephemeris for 1832,
in the first calendar page for August. In the co-
lumn of Moon’s declination for that month, her
longitude is, by a strange mistake, inserted. I en-
treat the especial favour of your allowing me to
insert the correct column of declination in your
valuable publication, as in the margin.

Also, at p. 42, January column, for 1 moon in
perigee read 1 moon in apogee, for 16 moon in
apogee read 16 moon in perigee; and insert, 29
moon in apogee.

I am,
My dear Sir,
Yours very faithfully,
O.intHus GREGORY.
Royal Military Academy,
Nov. 24, 1831.

ON VANADIUM. BY MR. JOHNSTONE.

** An ¢ Old Correspondent’ in the August Number of the Philoso-
phical Magazine and Annals, p. 157, mentions my having found
vanadium in an ore of lead from Alston Moor, and suggests that it
was more probably from the neighbourhood of Keswick.—On this
1 have only to remark, that I have never found it, and never said it
was to be found in ores of lead, except the two varieties described
in the former Number of this Journal, p. 166, as formerly occurring
in a now unwrought mine at Wanlockhead.”—Edinb. Journ. of
Science, Oct. 1831. p. 223. ————-

LIST OF NEW PATENTS.

To W. Morgan, York Terrace, Regent’s Park, esq., for certain
improvements in steam-engines.— Dated the 14th of February,
1831.—6 months allowed to enrol specification. :

oO

New Patents. 469

To J. Thomson, Spencer-street, Goswell-street road, gentleman,
for certain improvements in making or producing printing types.—
14th of February.—6 months,

To T. Bailey, Leicester, frame-smith, and C. Bailey, of the same
place, frame-smith, for certain improvements in machinery for
making lace, commonly called bobbin-net.—15th of February.—
6 months.

To W. Payne, New Bond-street, watch and clock maker, for an
improved pedometer for the waistcoat pocket, upon a new and very
simple construction.—15th of February —2 months.

To J. Grime, the younger, Bury, Lancashire, copper-plate
engraver, for a certain method of dissolving snow and ice on the
trams or rail-ways, in order that locomotive steam-engines and
carriages and other carriages may pass over rail-roads without any
obstruction or impediment from such snow or ice.—2ist of Fe-
bruary.—6 months.

To R. Burgess, Northwich, Cheshire, M.D., for a drink for the
cure, prevention, or relief of gout, gravel, and other diseases, which
may be also applied to other purposes.—2|st of February.—2 mon.

To S. Dunn, Southampton, engineer, for certainimprovements in,
or a method of, generating steam.—21st of February.—6 months.

To R. Trevithick, St. Aith, Cornwall, engineer, foran improved
steam-engine.—21st of February.—6 months.

To R. Trevithick, St. Aith, Cornwall, engineer, for a method or
apparatus for heating apartments.—21st of February.—6 months.

To W. Sneath, Ison Green, Nottinghamshire, lace-maker, for
certain improvements in, or additions to, machinery for making,
figuring, or ornamenting lace or net, and such other articles to
which the said machinery may be applicable.—21st of February.—
6 months.

To R. Abbey, Walthamstow, Essex, gentleman, for a new mode
of preparing the leaf of a British plant, for the producing a healthy
beverage by infusion.—21st of February.—6 months.

To W. Furnivals, Wharton, Cheshire, esq. for certain improve-
ments in evaporating brine.—2]st of February.—6 months,

To J. Phillips, Arnold, Nottinghamshire, servant-man, for cer-
tain improvements on bridles.—21st of February.—6 months.

To R. Williams, College Wharf, Belvidere Road, Lambeth,
Surrey, engineer, for certain improvements in steam-engines.—
28th of February.—6 months,

To D. Seldon, borough of Liverpool, merchant, for a certain
improvement or improvements in machinery used to give a degree
of consistency to, and to wind on to, bobbins, barrels or spools,
rovings of cottons, and the like fibrous substances. Communicated
by a foreigner —26th of February.—6 months.

To D. Napier, Warren-street, Fitzroy-square, engincer ; and
J. Napier and W, Napier, Glasgow, engineers, for certain improve-
ments in machinery for propelling locomotive carriages.—4th of
March,—6 months,

METEORO-

470 Meteorological Observations for October 1831.

LUNAR OCCULTATIONS FOR DECEMBER.

Occultations of Planets and fixed Stars by the Moon, in December
1831. Computed for Greenwich, by THomas HENDERSON, Esq. ;
and circulated by the Astronomical Society.

Immersions. Emersions.

eins
Lao | iS) “>... ey ot Te Onn
313 S Angle from Angle from
“2 |8'Z |Sidereal| Mean |, ~|Sidere: M Taare,
9 ae time. |solartime.| $6 § pba nolakiachil ae §
= (3 zu] 5 zm! 3s
Dis OY hPa tl es |e m0] ey ema gs 5
21 30] 4 23 1174]185/21 57| 4 51 |214| 229
6 (2653) 2 6] 8 51 | 95)128] Under\horizon.| ... | -..
ats 5 | 255123 58] 6 23/103] 76/ 1 6| 7 31 |307/291
possuee 4 | 293} 8 56| 15 20 | 125] 164} Underlhorizon.| ... | -.
5°6 | 379} 250} 911] 53] 46) 3 28] 9 49 | 349} 350
3°4| 478/21 19] 3 37 | 99] 61/22 10] 4 27 | 293) 253
6 | 508) 0 59 7 161128} 90] 1 59 8 17 | 268 | 238
5 | 510} 118} 7 35 | 18] 343)|) almost touching Star.—

Occulted to places further
North.

5°6| 516} 155} 812] 61] 29] 2 42] 8 59 |333)310

1 | 528} 4 46; 11 2] 48] 53) 5 25| 11 42 | 340) 355

5°6 | 663; 0 58] 7111120} 79) 155] 8 9 |266| 227

56| 2 29] 8 42 | 290] 254

20|\2 Geminor.} 6 | 951) 2 49) 8 55 | 35/354) 3 23) 9 28 | 325| 284

22\Regulus,...| 1 {1209/13 44] 19 39 | 68]105|14 45] 20 40 | 250/290

* Double Star.

METEOROLOGICAL OBSERVATIONS FOR OCTOBER 1831.
Gosport :—Numerical Results for the Month.

Barom. Max. 30-428. Oct. 17. Wind N.—Min. 29-231. Oct. 1. Wind S.
Range of the mercury 1-197.

Mean barometrical pressure for the Month .......cssceeceereereeeeee 29-904
Spaces described by the rising and falling of the mercury............ 4-865
Greatest variation in 24 hours 0:594.—Number of changes 16.

Therm. Max. 68°. Oct. 6. Wind S.W.—Min. 40°. Oct. 29. Wind N.W.
Range 28°.—Mean temp. of exter. air 57°°58. For 31 days with © in 59°68
Max. var. in 24 hours 19°-00.— Mean temp. of spring water at 8 A.M. 54:30

De Luc’s Whalebone Hygrometer.
Greatest humidity of the atmosphere, in the evening of the 12th...... 97°

Greatest dryness of the atmosphere, in the afternoon of the 5th...... 61-0
Rane onthe Wudex seve deeeteceranenneee teddideertsecccs te eces uc vase eoce eames 36-0
Mean at 2 P.M. 72°-6.—Mean at 8 A.M. 78°1.— Mean at 8 P.M. 82:0

of three observations each day at 8, 2, and 8 o’clock ......... 776

Evaporation for the month 1-60 inch.
Rain in the pluviameter near the ground 4-835 inches.
Prevailing wind, South-west.
Summary of the Weather.
A clear sky, 2; fine, with various modifications of clouds, 13; an over-
cast sky without rain, 8; foggy, 4; rain, 74.—Total 31 days.
Clouds.

Meteorological Observations for October 1831. 471

Clouds.
Cirrus. Cirrocumulus. Cirrostratus. Stratus. Cumulus. Cumulostr. Nimbus.
19 i 30 1 19 24 ee

Scale of the prevailing Winds.

N. N.E. Es Shee oS: SaWeaewWin ) NEW. Days.
PR RE Semeeky Ts ER rep OTR ck 31

General Observations. — This month has been remarkably mild for the
season, but windy and very wet, it having rained more or less on twenty-
three days, and the amount is one inch and a half more than the mean
depth of October for a series of years; the rain was cften accompanied
with brisk gales from the South-west. From the absence of frost the mean
temperature of the external air this month is four degrees higher than the
mean of October for many years past; and the temperature of spring water
has decreased very little from its maximum for the year. A large lunar
halo presented itself several hours in the evening of the 16th, and solar
halos on the 28th and 30th.

On the 29th at 10 P.M. an aurora borealis appeared, and rose slowly
till a quarter past 11, when its lower arch was at its greatest height in the
magnetic north, viz. about 16° and 73° in extent on the horizon, At
this time a few columns of light ascended from beneath the arch, but
they were thin and rather faint, and did not reach much higher than the
head of the Dragon. By 12 o’clock the aurora had disappeared, and was
followed by a gale of wind in less than twenty-four hours.

The atmospheric and meteoric phanomena that have come within our
observations this month, are, one lunar and two solar halos, eight meteors,
two rainbows, an aurora borealis, and eleven gales of wind, or days on
which they have prevailed, namely, two from the South, seven from the
South-west, and two from the West.

REMARKS,

London. — October 1. Cloudy and warm: rain. 2, Cloudy: fine-
3, 4. Fine: rain at nights. 5—7.Fine. 8. Cloudy: heavy rain and thunder
at noon: foggy. 9. Overcast:fine. 10.Fine. 11.Rain. 12. Continued
rain, becoming very heavy at night; depth amounting to the unusual quan-
tity of one inch in twenty-four hours. 13. Rain: cloudy and windy at
night. 14. Fine: showers. 15. Stormy and wet: clear. 16, 17. Fine.
18. Foggy. 19.Veryfine. 20. Overcast: fine. 21.Rain:clear. 22, Stormy,
with rain. 23. Rain: clear. 24. Fine: overcast. 25. Rain: clear and fine:
windy, with rain at night. 26. Slight showers: rain and thick fog at night.
27.Rain. 28. Very fine. 29. Slight fog: fine. 30,31. Fine.

Penzance.—October 1.Fair: showers. 2.Fair. 3,4. Rain. 5,6. Fair.
7. Rain: fair. 8.Showers: fair. 9.Fair:rain. 10. Fair: showers. 11. Fair.
12. Fair: showers. 13.Fair: rain. 14—17.Fair. 18. Rain. 19. Fair.
20.Rain. 21.Fair. 22,23. Rain. 24. Fair. 25.Showers. 26. Rain.
27. Fair: showers. 28—30.Fair. 31. Fair: showers.

Boston. — October 1. Rain: rain early a.m. 2, Cloudy: rain early a.m.
3. Cloudy: rain at night. 4,5. Fine: rain early a.m. 6.Rain. 7. Fine.
rain early a.m. 8.Fine:rainr.m. 9.Cloudy. 10.Fine. 11. Cloudy.
12. Cloudy: rain p.m. 13.Cloudy. 14. Rainand stormy. 15—17. Fine.
18. Foggy. 19, 20. Cloudy. 21. Rain. 22. Fine: stormy night.
23. Cloudy: rain a.m. and p.m. 24. Fine. 25. Cloudy. 26. Fine.
27.Cloudy: rainatnight. 28.Fine. 29,Cloudy. 30.Fine. 31.Cloudy.

Metcoro-

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WC CHurgeons Capfterume nhs on the MhermoMaspetion of Homogencots Wocles

Phii. Mag. & Annuals N. 3. Voll0 Plate 2.

, Yl Ya nills hey she L- Vy WHOAET

; PINS i. | aid ay i Ss A

‘art

To be had of Messrs. Treuttel and Wirtz, Treuttel, Jun. and Richter,
30 Soho-Square; and R. Hunter, St. Paul’s Churchyard.

LE PROTESTANT DE GENEVE,
JOURNAL THEOLOGIQUE ET RELIGIEUX.

Je vous parle comme a des personnes intelligentes;
jugez vous-mémes de ce que je dis.—(1 Cor. x. 15.)

L* publicité, ce besoin si général de notre époque, est devenu aussi
pour |’Eglise de Genéve une nécessité qu'il n’est plus possible de
méconnaitre, et devant laquelle, par conséquent, il n’est plus permis de
reculer. D’une part, les amis de cette Eglise demandent 4 ses con-
ducteurs de manifester au public religieux quels sont les principes qui
la dirigent aujourd’hui; d’autre part, ses ennemis prennent occasion de
son silence pour attaquer sa doctrine, calomnier ses actes, et la taxer elle-
méme de crainte ou d’infidélité. C’est donc pour répondre 4 la fois a ces
demandes et a ces attaques que plusieurs membres de cette Eglise, ecclé-
siastiques et laiques, croient devoir fonder un journal. Dans un premier
numéro, ils exposeront en détail quelles sont Jeurs vues générales et
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Le Protestant de Genéve aura pour but de développer et de défendre
les principes du Protestantisme, tels qu’ils sont actuellement compris et

rofessés dans l’Eglise nationale de cette ville, oi, depuis trois siécles,
ils ont porté, par la bénédiction du Trés-Haut, des fruits de liberté et
de piété, qui n’ont pas été sans gloire.

e journal recevra avec reconnaissance tous les renseignements qui
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Le Protestant de Genéve paraitra le 1 et le 15 de chaque mois par
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Les lettres et envois divers doivent étre adressés, francs de port, au
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Cité, a Genéve.

Le prix de l'abonnement est, pour Genéve et la Suisse, de

10 fr. de France pour un an.
6 fr. id. pour six mois.
Pour la France et autres pays,
#15 fr. pour un an,
7 fr. pour six mois.

ON 8S’ABONNE
A Genéve, chez M. Ab. Cherbuliez ;

A Paris, méme maison, rue de Seine St. Germain, No. 57 ;
Et chez les principaux libraires de la France et de !’étranger.

CONTENTS or Ne 55.— New Series.

I. On the Thermo-Magnetism of Homogeneous Bodies ; with illus-
trative Experiments. By Mr. WM. SturGEON, Lecturer on Experi-
mental Philosophy at the Hon, East India Company’s Military Aca-
demy, Adiscombe. (With a Plate.) (To be continued) ..... wo page I

II. On Simple Elimination, By J. E. Drinkwater, Esq....... 24

a
II, On the Solar Eclipses and Transit of Mercury over the Sun’s
Disc in 1832. By Prof. ENCKE..... BE be Ln ae Re 28

IV. Of the Conditions of Life. By the Rev. Parrick KEITH,
BLL. S.( Lo, be continued). «<i sjs:ba0's &b eieisio bivivi. 69 walle) lols <form ovis: x82

V. Proceedings of Learned Societies :—Royal Society ; Geological
Society; Astronomical Society; Zoological Society ; Friday-Evening
Proceedings of the Royal Institution of Great Britain,...... wa.) 41-67

VI. Intelligence and Miscellaneous Articles :— Account of an
Aérial Voyage made in a Balloon on Saturday the 30th of April
1831, by T, Forster, M.B. F.L.S. &c.; New Patents; Occulta-
tions of Planets and Fixed Stars by the Moon in July 1831;
Results of a Meteorological Journal for the year 1830, kept at the
Observatory of the Royal Academy, Gosport, Hants, by William. ;
Burney, LL.D. ; Extract from the Meteorological Journal kept at ;
Penzance, by Mr. Giddy; Meteorological Observations for. May. 3
1891; Table; Bd... 4... oh Grae PS: AE iy 67-80

*,° It is requested that all Communications for this Work may be addressed, ©
post paid, to the Care of Mr. R. Taylor, Printing Office, Red Lion Court, 4
Fleet Street, London; where complete Sets of the Old Series of the Phi-
_ losophical Magazine may be had at half of the original price, |

Just published, in quarto, Price Thirty Shillings,

Illustrated by Nine highly-finished Engravings ; viz. Four large folding Plates of
the Survey of the Thames, and the Instruments employed; one Quarto and
two folding Plates of the Graphical Registrer of the Tides and Wind, and two
Quarto Plates of the Magnetic Apparatus, and Illustrations of the paper ;

4 it PHILOSOPHICAL TRANSACTIONS OF THE ROYAL
SOCIETY of LONDON, 1831, Parr I.

Contents :—Capt. Rosertson’s Observations on the Comet of 1822.
—Prof. Bartow on Fluid Refracting Telescopes.— LusBock’s Re-
searches in Physical Astronomy.—Harris on the Transient Magnetic
State of Substances. GILBERT on Negative and Imaginary Quantities.—
Prof. Bartow on the Phenomena of Terrestrial Magnetism.—Ivory on
the Equilibrium of Fluids.—Prof. Davy on an Electro-Chemical Method
of detecting Metallic Poisons.—Barry on Atmospheric Electricity.—
Loyp’s Survey of the River Thames from London Bridge to the Sea.—
ox on the Variable Intensity of Terrestrial Magnetism.—PALMER on a
Graphical Registrer of Tides and Winds.—Prof. Barniow on the Errors
in the Course of Vessels from Local Attraction—Lussock on the Me-
teorological Observations made at the Royal Society.—Meteorological |
Journal of the Royal Society, June to December 1830.

This Day is published, in one thick volume, 12mo, with 104 Wood-cuts,
Price 18s.

GEOLOGICAL MANUAL. By HENRY T. DELA BECHE,
Esq. F.R.S. F.G.S: Mem. Geological Society of France, &c.

Printed for Treuttel, Wiirtz, and Co. 30, Soho-Square.

CONTENTS or J

>

VII. On some Problems in Analytical Geometry. By J. W. Lus-
BOCK, Esq. V.P. & Treas. R.S @eeeececee eeoeoe esos etree eseeaee page 81
VII. Particulars of the Measurement, by various Methods, of the
instrumental Error of the Horizon-Sector described in Phil. Mag.
vol. lix. By Joun Nixon, Esq. (To be continued) .........-.... 88
IX. Notes on some recent Improvements of the Steam-Engines in
Cornwall. By W. Jory Henwoop, F.G.S. Member of the Royal
Geological Society of Cornwall..............++eeeeeness Bs pies ae,
X. On Chemical Symbols and Notation; in Reply to Professor
Whewell. By Mr. Joun Pripeaux, Member of the Plymouth
PeSEM GLOW 03. cic s aisiaieis ose secs n.e sete Capes PAS, 1 Fuk os ee
XI. On Poonahlite, a new Species of Mineral; on the Identity of
Zeagonite and Phillipsite, &c,; and other Mineralogical Notices. By ~

H. J. Brooke, Esq. F.R.S.L.S. & G'S. ........... sicies PEERES oars 109
XII. On the Theories of Achromatization, &c.in Reply to Dr. - »
Goring. By the Rev. H. Coppineron.,......... es ae Raetiet ale 112

XIII. On the Thermo-Magnetism of Homogeneous Bodies; with
illustrative Experiments. By Mr. Wm. Srurceon, Lecturer on Ex-
perimental Philosophy at the Hon, East India Company’s Military —

Academy, Adiscombe ............... PPAR eae ats a i oa niet . 116
XIV. Of the Conditions of Life. By the Rev. Parrick KEITH, -—
BLS cia bis eisentieteta nin Site & pao weeleranh essa ook A als ok anatre dee ve Lee

XV. On the Statement in the Nautical Almanac for }833, of the
Time of Beginning of the Solar Eclipse of the 16th of July in that
Year; together with the correct Times of that Eclipse, computed —~
for Greenwich. By GrorceE Innzs, Esq........... SUES Sy ee ieee

XVI. Errata in Schumacher’s Ephemeris of the Distances of the ° -
four Planets Venus, Mars, Jupiter, and Saturn, from the Moon’s —
Centre, &c. for 1833, published by the Admiralty. By A Corre-

XVIII. New Optical Experiments by Professor Airy. ........ 141
XIX, Proceedings of Learned Societies :— Geological Society ;
ZQGIOR ICH ROUEEY ya ore es no rdle i's 3s: etedy ap iw Sane wes's gl bmg le -- 143-150
XX. Intelligence and Miscellaneous Articles:— General Scientific
Meeting at York; On the Rapid Flight of Insects; Process for pre-
paring Hydrocyanic Acid; Vanadium, a New Metal ; Magnesium;
On Oxalic Acid, by M. Gay-Lussac ; On Gallic and Pyrogallic Acid,
by M. Henri Braconnot; Analysis of Tennantite, by J. Hemming,
Esq.; New Patents ; Occultations of Planets and Fixed Stars by
the Moon in August 1831; Meteorological Observations for June —
18315; Tablepiscas a 2 See Sta es “wo eels a Speen folic paves Pama 150-160

*,° It is requested that all Communications for this Work may be addressed, |

post paid, to the Care of Mr.R. Taylor, Printing Office, Red Lion Court,

Fleet Street, London; where complete Sets of the Old Series of the Phi- |
losophical Magazine may be had at half of the original price,

wh

This Day is Published,

A LETTER to Dr. DAVID BOSWELL REID, Experimental As-
sistant to Dr. Horr, &c.; in answer to his Pamphlet entitled
*¢ An Exposure of the Misrepresentations in the Philosophical Magazine
and Annals,” &c.

By RICHARD PHILLIPS, F.R.S. L.& E., &c.
- Samuel Highley, 174 Fleet Street. Price 1s.

Just Published, in quarto, Price Thirty Shillings,

Illustrated by Nine Engravings; viz. Four large folding Plates of the Survey of
_ the Thames, and: the Instruments employed ; One Quarto and Two folding Plates
; of the Graphical Registrer of the Tides and Wind ; and Two Quarto Plates of
_ Magnetic Apparatus, and Illustrations of the paper on Negative Quantities ;

| HE PHILOSOPHICAL TRANSACTIONS OF THE ROYAL
. SOCIETY of LONDON, 1831, Parr I.

Contents :—Capt. Rozertson’s Observations on the Comet of 1822,
_—Prof. Bartow on Fluid Refracting Telescopes.—Mr. Luszocx’s Re-
"searches in Physical Astronomy.—Mr. W. Snow Harris on the Trans-
ient Magnetic State of different Substances.—Mr. Davies GILBERT on
_ Negative and Imaginary Quantities,—Prof. BARLow on the Phenomena
_ of Terrestrial Magnetism.—Mr. Ivory on the Equilibrium of Fluids, and

:
4

_ the Figure of a Homogeneous Planet.—Prof. Davy on an Electro-Che-
mical Method of Detecting Metallic Poisons.—Mr,. Barry on Atmo-
? esc Electricity. —Mr. Lioyp’s Survey of the River Thames, from Lon-
a on Bridge to the Sea.—Mr. Fox on the Variable Intensity of Terrestrial

_Magnetism.—Mr. Patmer on a Graphical Registrer of the Tides and

-Wind.—Prof. Bartow on the Errors in the Course of Vessels from Lo-
_ eal Attraction.—Mr. Lussock on the Meteorological Observations made
at the Royal Society.—The Meteorological Journal of the Royal Society,
_ from June to December 1830.

_—

THE POLYTECHNIC LIBRARY.

HE design of the Publishers of the «« POLYTECHNIC LIBRARY”
; is to produce a series of highly instructive Works, which the pub-
lic may be tempted to buy, because they will be cheap,—be induced to
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e Works or Pracricat Uriciry. Every Volume, therefore, will
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‘This day is Published, Vol. I. of the « POLYTECHNIC LIBRARY,”
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wo Shillings, bound in Cloth, containing
- The ART OF GLASS-BLOWING ;; or Plain Instructions for making
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lass, such as Barometers, Thermometers, Hydrometers, Tube Vessels,
Toys for Chemical Experiments and Recreative Philosophy. By a

Printed for Bumpus and Griffin, 3 Skinner Street, London; Richard
Griffin & Co., Glasgow, and Stillies, Brothers, Edinburgh :—By whom
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the DOMESTIC CHEMIST; or Instructions for the Detection of Adul-
terations in Food ; and Vol. III. containing the PERFUMER’S ORA-
LE; or Art of Preparing Perfumes and Cosmetics.

CONTENTS or N° 57.—New Series.

XXI. OnIsomorphism. By H. J. Brooke, Esq. F.R., L.,& GS.
page 161.

XXII. Exposition of a New Dynamico-Chemical Principle. By
Mr. Joun JamES WATERSTONE,........-.265-- b aibiaays aboshenitalivbs 170

XXIII. An Examination of M. Virey’s Observations on Aéronautic
Spiders, published in the Bulletin des Sciences Naturelles. By JoHN
BLACK WALES SiGe HET e lao elaks: she ebeielsiv nial othlecre « fe dates SO

XXIV. On Mengite, a new Species of Mineral; on the Characters
of Aeschenite ; on Sarcolite, as distinct from Analcime and Gmelinite ;
with other Mineralogical Notices, By H. J. Brooxs, Esq. F.R., L.,
ad Git IG a ER const on Aina SAN ie oi aad, ale -chaypte yore keene 187 —

XXV. On a New Register-Pyrometer, for Measuring the Expan-
sions of Solids, and determining the higher Degrees of Temperature '
upon the common Thermometric Scale. By J. FrepERic DANIELL,
Esq. F.R.S, (With a Plate) (To be continued),......... Ma SER Fast - 191

XXVI. On the Theory of the Compressibility of the Matter com- .
posing the Nucleus of the Earth, as confirmed by what is known of
the Ellipticities of the Planets. By the Rev. J. Cuaxtis, Fellow of
the Cambridge Philosophical Society... ..............e0000 ee: 200

XXVII. Analysis of some Salts of Mercury. By R. PHiLuips,
Bose Ware BC Hy BEC oes go 3 ios en's! tie ate or nie oom tual haley piel ate Seine ao

XXVIII. Experiments on Vanadiate of Ammonia, and on some
other Compounds of Vanadium. By Mr.Joun PripEAux, Member
of the Plymouth Institution :,..; <0 cise: otic ciecee eee Byere.s 7" 209

XXIX. Notices respecting New Books: — Dr, Paris’s Life of Sir
Humphry Davy. (To be continued) ..........-0.eeaeeees snaimeeeaa

XXX. Proceedings of Learned Societies: — Royal Society; |
Zoological Society ........ Boies as» iy e.'es at yale mtigrer Osama -. 223-235

XXXI. Intelligence and Miscellaneous Articles:— Preparation of
Iodic Acid, by Arthur Connell, A.M.; New Scientific Books; Mr.
Saull’s Geological Museum; Occultations of Planets and Fixed Stars
by the Moon in September 1831 ; Meteorological Observations for —
July 1831 ; Table, &c..... Maecenas 2 tas’ 6) cuneate hats hat ee 235-240

Fleet Street, London; where complete Sets of the Old Series of the Phi
losophical Magazine may be had at half of the original price,

DR. WEBSTER’S ENGLISH DICTIONARY.

DICTIONARY OF THE ENGLISH LANGUAGE, intended

to exhibit:—1. The Origin and the Affinities of every English Word,
as far as they have been ascertained, with its Primary Signification, as
now generally established.—2. The Orthography, and the Pronunciation
of Words, as sanctioned by reputable Usage, and where this Usage is di-
vided, as determinable by a reference to the Principle of Analogy.—
3. Accurate and Discriminating Definitions of Technical and Scientific
Terms, with numerous Authorities and Illustrations. ‘To which are pre-
fixed, An Introductory Dissertation on the Origin, History, and Connec-
tion of the Languages of Western Asia and of Europe, and a concise
Grammar of the English Language.

By N. WEBSTER, LL.D.

This Work will appear in 12 Parts, each consisting of 20 Sheets, form-
ing 2 vols.4to. It is not a mere improvement on Johnson’s Dictionary,
but an original work, the labor of 30 years, and contains 12,000 words
more than any other similar work, In respect to Etymologies and Affi-
nities, it supplies the grand desideratum in English Lexicography.

*,* Part XI. is just published, Price 9s.
Vol, I. may be had in Cloth Boards, and Lettered, 31. 3s.

The Proprietors of Dr. Wesster’s EnciisH Dictionary have pur-
chased from the family of the late Rev. JonatHan Boucuer, Vicar of
Epsom, the valuable and voluminous MSS. which he had, during the last
fourteen years of his life, prepared for a“ GLOSSARY of PROVIN-
CIAL and ARCHAZOLOGICAL WORDS,” intended as a Supple-
ment to Dr. Johnson’s Dictionary: and they mean to publish these MSS.
in One Volume, 4to. as a Supplement to Dr. WensTER’s Encuisu Die-
TIONARY. The larger portion of the MSS. is in a state fit for publica-
tion; and the Supplement will be commenced as soon as the work of Dr.
Wessrter is completed. They also intend to publish an OCTAVO Edition
of Dr. Wesster’s Encuisn Dictionary, which will contain all the
technical and scientific definitions of the Quarto Work, but without the
copious etymological matter, which will not be required by general readers
for ordinary purposes. A multitude of Words collected by the Editor,
will be inserted; and also a large collection of ARcHAIc TERMS from
the MSS. of the late Rev. JonatHan Boucuen.

Published by Black, Young, and Young, Foreign Booksellers to the
King, 2 Tavistock Street, Covent Garden.

CONTENTS or N° 58.—New Series.

XXXII. Researches on some of the Revolutions which have taken
place on the Surface of the Globe; presenting various Examples of
the Coincidence between the Elevation of Beds in certain Systems
of Mountains, and the sudden Changes which have produced the
Lines of Demarcation observable in certain Stages of the Sedimen-

tary Deposits. By L. Ex1z pz BEAuMoNT...... cove creas a npage Dal
XXXIII. On an undescribed Bird of the Family Falconide, By
JoHN BLACKWALL, Esq. iF.LAS. 100). cdinn seve cs cee sa nnneeels »+- 264

XXXIV. On Monticellite, a new Species of Mineral; on the Cha-
racters of Zoizite; and on Cupreous Sulphate of Lead. By H. J.
BROOKE, Esq. Pj Ug BGS. pac ae ciate ins = a;5ial'e nt ieee peas 265

XXXV. On a New Register-Pyrometer, for Measuring the Ex- —
pansions of Solids, and determining the higher Degrees of Tempera-
ture upon the common Thermometric Scale. By J. FREDERIC
DantELL, Esq. F.R.S. (To be continued) ..........+ aS a egnte ae 268

XXXVI. On the Calculation of the Orbits of Double Stars. By
Professor ENCKE (To be continued) ...... 0... 20es ceee rene wewics ee

XXXVII. New Method of Levelling the Axis of a Transit Instru-
ment, “ By' 5. Wrsons Rise sh .75 ioe hae oth 's nes a che iano enn 284

XXXVIII. Notices respecting New Books:—Young’s Elementary
Treatise on the Differential Calculus ..................0020000- 287

XXXIX. Proceedings of Learned Societies: — Royal Society ;
Loclopical 'Seciety'< ii. 27070 0 287. a NE es Oe, oe 293-313

XL. Intelligence and Miscellaneous Articles:— Red Colouring
Matter produced by the Action of Nitric Acid upon Alcohol, &c.
by M. Rouchas; Perchloric Acid; Red Solutions of Manganese ;
Powerful Electro-Magnet; Marking-Ink for Linen ; Monthly Ame-
rican Journal of Geology and Natural Science; Mr, Harvey’s Re-
searches on Naval Architecture; List of Patents ; Occultations of
Planets and Fixed Stars by the Moon in October 1831 ; Meteoro-
logical Observations for August 1831 ; Table, &c........... . . 313-320

*," It is requested that all Communications for this Work may be addressed,
post paid, to the Care of Mr. R. Taylor, Printing Office, Red Lion Court,
Fleet Street, London; where complete Sets of the Old Series of the Phi-
losophical Magazine may be had at half of the original price.

Just published, Price 6s. in Cloth,

ee Se ON THE MANUFACTURES IN METAL: Vol. 1.
Iron and STEEL.
Being Vol. 24 of “ Dr. LARDNER’s CABINET CycLoPz=pIA.”

Published Oct.1, History of France. By E, E. Crowe. (3 Vols.)
Vol, I1I.—To be published Dec. 1, Lives of DistincuIsHep BritisH
Mitirary ComMAnpERs. By the Rev. G. R. Grete. (3 Vols.) Vol. I.

Printed for Longman and Co., and John Taylor.

DR. WEBSTER’S ENGLISH DICTIONARY.

DICTIONARY OF THE ENGLISH LANGUAGE, intended

to exhibit:—1. The Origin and the Affinities of every English Word,
as far as they have been ascertained, with its Primary Signification, as
now generally established.—2. The Orthography, and the Pronunciation
of Words, as sanctioned by reputable Usage, and where this Usage is
divided, as determinable by a reference to the Principle of Analogy.—
3. Accurate and Discriminating Definitions of Technical and Scientific
Terms, with numerous Authorities and Illustrations. To which are pre-
fixed, An Introductory Dissertation on the Origin, History, and Connec-
tion of the Languages of Western Asia and of Europe, and a concise
Grammar of the English Language.

By N. WEBSTER, LL.D.

This Work will appear in 12 Parts, each consisting of 20 Sheets, form-
ing 2 vols,4to. It is not a mere improvement on Johnson’s Dictionary,
but an original work, the labour of 30 years, and contains 12,000 words
more than any other similar work, In respect to Etymologies and Affi-
nities, it supplies the grand desideratum in English Lexicography.

*,* Part XI. is just published, Price 9s.
Vol. I. may be had in Cloth Boards, and Lettered: 31. 3s.

. The Proprietors of Dr. Wesster’s ENciisn Dictionary have pur-
chased from the family of the late Rev, JonatHan Boucuer, Vicar of
Epsom, the valuable and voluminous MSS. which he had, during the last
fourteen years of his life, prepared for a ““ GLOSSARY of PROVIN-
CIAL and ARCHZOLOGICAL WORDS,” intended as a Supple-
ment to Dr. Johnson’s Dictionary: and they mean to publish these MSS.

in One Volume, 4to. as a Supplement to Dr. WezstER’s Encisn Dic-
-gionary. The larger portion of the MSS. is in a state fit for publica-
tion; and the Supplement will be commenced as soon as the wor of Dr.
_ WexzsTER is completed. They also intend to publish an OCTAVO Edition
of Dr. Wesster’s Enciisn Dictionary, which will contain all the

technical and scientific definitions of the Quarto Work, but without the
_ copious etymological matter, which will not be required by general readers
for ordinary purposes. A multitude of Words collected by the Editor,
_ will be inserted; and also a large collection of ArcHAIc TerMs from
_ the MSS. of the late Rev. Jonatuan Boucuer.

_ Published by Black, Young, and Young, Foreign Booksellers to the
King, 2 Tavistock Street, Covent Garden.

CONTENTS or N°59.—New Series.

XLI. On Vanadium. By M. Berzetus (To be continued)... page 321
XLII. Particulars of the Measurement, by various Methods, of
the Instrumental Error of the Horizon-Sector described in Phil.
Mag. vol. lix. By J. Nrxon, Esq. ( To be continued) .......+.- pee OOl

XLII. Notice on Oxalic Acid. By Epwarp Turvyer, M.D.
F.R.S. L. & E, &c., Professor of Chemistry in the University of
London,....... bee Patt «8 EES ae Betas sone alee eseeg 988

XLIV. On a New Register-Pyrometer, for Measuring the Ex- >
pansions of Solids, and determining the higher Degrees of Tempera-
ture upon the common Thermometric Scale. By J. FREDERIC
DANTEMM E60. hMedee's siajeiiarneieged > usidwtienles eid ale I ae AEs 350:

XLV. Correction of a Quotation in a Paper “On the Impediments
to the Study of Natural History,” published in the Phil. Mag. and —
Annals for May, 1831, By W. S, MacLeay, Esq. M.A.F.LS., &e. 357

XLVI. Notice of a Geological Survey of the Mines of Cornwall ;
with a Programme of an intended Arrangement of the leading De-
tails of the Metalliferous Veins, &c. By W. Jory Henwoop, F.G.S. 358 _

XLVII. Experiments on the Disinfecting Powers of increased
Temperatures, with a view to the Suggestion of a Substitute for
Quarantine. By Wir1i1am Henry, M.D. F.R.S, &c...... ews. OOS

XLVIII. Notices respecting New Books:—Mr, Rennie’s Edition
of Montagu’s Ornithological Dictionary; Dr. Paris’s Life of Sir
Humphry Davy, Bart. ( To be continued) .........ee0eeees - 370-386

XLIX. Proceedings of Learned Societies : —British Association
for the Promotion of Science; Zoological Society ........... 387-392

L. Intelligence and Miscellaneous Articles: — On the Atomic
Weight of Barytes, by Dr. Thomson; On the Oxichlorates, by
M. Serullas; Occultations of Planets and Fixed Stars by the Moon —
in November 1831; Meteorological Observations for September
1831; Table, &c.; Calendar of the Meetings of the Scientific Bodies _
of London for 1831-32........ Sy thee vr,k a brat ol mene . 892-400 —

*,” It is requested that all Communications for this Work may be addressed,
post paid, to the Care of Mr. R. Taylor, Printing Office, Red Lion Court,
Fleet Street, London; where complete Sets of the Old Series of the Phi-
losophical Magazine may be had at half of the original price.

y
0

f
i

‘

fs ‘Sharpe (S.). On the Solid of greatest Attraction.

Children (J. G.) F.R.S. On Ochsenheimer’s Genera of Lepidoptera.

Articles in the Philosophical Magazine and Annals for June, July,
August, September, and October, 1830, and November 1831.

Vernon (Rev. W.V.) F.R.S. Chemical Examination of artificial Brucite.
Herapath (W.). On the Combustion of the Diamond.
Schmidt (Dr. E.). On the Dimensions of the Earth.
Ivory (J.) F.R.S. On the Figure of the Earth. And, On the shortest Di-
stance between two Points on the Earth’s Surface.
Lubbock (J. W.) F.R.S. On the Census.
Farey (J.). On Improvements in the Steam-engine.
Taylor (J.) F.R.S. On the Duty of Steam-engines in Cornwall.
MacLeay (W.S.) F.L.S. On the Dichotomous Method in Natural History.
Roget (P.M.) Sec. R.S. Letter in refutation of an alleged Inaccuracy in
the Minutes of the Council of the Royal Society.
Gilbert (Davies) Pres. R.S. On the same subject. ~
Babbage (C.). F.R.S. Lucasian Professor of Mathematics, Cambridge,
on the same Subject.
Nixon (J.). On the Measurement (by Trigonometry) of the Heights of
the principal Hills of Swaledale, Yorkshire.
Galbraith (W.) M.A. On the Obliquity of the Ecliptic.
Witham (H.) F.G.S. On the Vegetable Fossils found at Lennel Braes,
near Coldstream, upon the Banks of the River Tweed.
Bevan (B.). On the Power of Horses.
Alison (R. E.). Narrative of an Excursion to the Summit of the Peak of
Teneriffe in February 1829.
De la Beche (H. T.) F.R.S. On the Geographical Distribution of Organic
Remains in the Oolite Series of England and France.
Sabine (E.) Capt. R.A. Sec. R.S. Notices occasioned by the Perusal of
a late Publication by Mr. Babbage.
Rumker (C.), Elements of the Comet in Pegasus ; with Observations and
Elements of the same Comet, by M. Valtz, of Nimes.
Fleming (Rev. Dr.). Note on Mr. MacLeay’s Abuse of the Dichotomous
Method in Natural History.

Sedgwick (Professor) and Murchison (R. I.), Esq. Pres. G.S. Sketch of the
Structure of the Austrian Alps. , 2
Prideaux (J.). On the mean Atomic Weights of Simple Bodies, according

' to Thomson and Berzelius.
Yarrell (W.) F.L.S. On a new Species of Swan. r
Challis (Rev. J.). A tempt to explain theoretically the different Refran-
gibility of the Rays of Light. ;
Noggerath (Prof. J.). On the Magnetic Polarity of two Rocks of Basalt
near Niicburg in the Eifel, ;
Meikle (H.). On the Giconomy of the Steam-engine. *
Conybeare Rev. W.D.). On Mr. Lyell’s ‘‘ Principles of Geology.
Squire (T.). On the computed times of a late Occultation of Aldebaran.

Berzelius (M.). On Vanadium.

Nixon (Mr.). On his Horizon Sector.

Turner (Dr.). On Oxalic Acid.

Daniell (Prof.). On his New Register-Pyrometer.

Henwood (W.J.). On a Geological Survey of the Mines of Cornwall.

Henry (Dr.). On a Substitute for Quarantine.

CONTENTS or N° 60.—Mew Series.

LI. On Isomorphism. In Reply to Mr. Brooke, [With a Note
on Mr, Prideaux’s remarks on Chemical Notation.] By Professor
Wnrewent, of Cambridge.............-+---- cetcvses »+..- page 401

LII. Unequal Refrangibility of Light on the Undulatory Theory.

By A CoRRESPONDENT........ Perea vi his a one's ve Seid Anite seth iy 442

LIII. On the Symmetrical Functions of a specified Number of
the Roots of an Equation. By the Rev. R. Murruy, Fellow of Caius
Coll. and of the Cambridge Philosophical Society. .............. 413

LIV. A Description of New Succulent Plants of the Natural
_ Orders Bromeliacee, Tulipacee, Crassulacea, Euphorbiacee, Cactee,
Ficoidee. By A, H. Hawortn, Esq. F.L.S. &.......... 00000 414 —

LV. Additional Remarks on Isomorphism. st aes J. - Brooxg, Esq.
PRS LAGOS! 275 250 5. eter. ol sdngeee ie as 424

LVI. Notices respecting New Books Zee Paris's Life of Sir
Humphry Davy, Bart. ; Mr. Rennie’s Edition of Montagu’s Orni-
thological Dictionary (To be continued) ............4..... 426-433

LVII. Proceedings of Learned Societies : —Geological Society ;
Linnzan Society ; Astronomical Society ; Zoological Society.. 433-465

LVIII. Intelligence and Miscellaneous Articles :—On Mudarine;
Preparation of Oxichlorate of Potash, by M. Serullas; Separation
of Antimony and Tin; Dr. Gregory on White's Ephemeris; On
Vanadium, by Mr. Johnstone ; List of New Patents ; Occultations of
Planets and Fixed Stars by the Moon in December 1831 ; Metéaro:
logical Observations for October 1831 ; Table, &c........... 465-472

Py Itvis requested that all Communications for this Work may be doesnt
post paid, to the Care of Mr. R. Taylor, Printing Office, Red Lion Court,
Fleet Street, London; where complete Sets of the Old Series of the Phi- :
losophical Magazine may be had at half of the original price. ;