Quarterly Journal of Science, Literature and the Arts

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THE

QUARTERLY. JOURNAL

or

SCIENCE,

LITERATURE, AND THE ARTS.

VOLUME XV.

LONDON :
JOHN MURRAY, ALBEMARLE-STREET.

ss

1823.

LONDON:
PRINTED BY WILLIAM CLOWES,
Northumberland-court.

CONTENTS

OF

THE QUARTERLY JOURNAL,

1s ae: D4 BG

ART. PAGE

I. On the Curvature of the Arches of the Bridge of the Holy Tri-
nity at Florence (with a Plate). By Samueu Wart, Esq.

II. A History of a painful and obstinate Affection of the Brain,
which ultimately yielded to the unremitting Application of
Cold, and the continued erect Position for a week. By
G.D. Years, M.D., F.R.S., Fel. of the Roy. Col. Phys.

Iff. An Account of the Rock Specimens collected by Captain
Parry, during the Northern Voyage of Discovery, per-
formed in the Years 1819 and 1820. By Cuaruzs Konie,
Esq., F.R.S., &c. - : :

IV. On the Influence of Local Attraction upon the Magnetic
Needle. By Mr. Jonn MAcneiLy - ;

VY. Lamarcnk’s Genera of Shells (with Plates) 5
VI. On a Mode of protecting the Specula of Reflecting Telescopes
Vit. Experimental Inquiries relative to the Formation of Mists.

By Georce Harvey, Esq., Member of the Astronomical
Society of London

VIII. On the Light produced by the — of an Air-gun

IX. Details of a Barometrical Measurement of the Sugar-loaf
Mountain at Sierra Leone, and of other Heights situated
within the Tropics. In a Letter from Captain Epwarp
Sazine, of the Royal Artillery, to J. F. Danretx, Esq.

X. On Hydrate of Chlorine. By M. Farapay, Chemical As-
sistant in the Royal Institution : : ‘

a

1

Se §

67

71

il CONTENTS.

ART. PAGE
XI. An Account of a Barometrical Measurement of the Height
of the Pico Ruivo, in the Island of Madeira. Extracted
from a Letter written by Captain Eowarp Sasine, of the
Royal Artillery, to Sir Humpury Davy, Bart., President
of the Royal Society, dated in January, 1822, on board his
Majesty's Ship Iphigenia, on passage between the Cape

Verd Islands and Goree 4 : 75
XII. Analysis of a New Sulphur Spline at Habits. By
Wit1iam West, Esq. - 82

XIII. On the Vibrations of Heavy Bodies i in C yeloidal sods in Cir-
cular Arches, as compared with their Descents through free
Space ; including an Estimate of the Variable Circular Ex-
cess in Vibrations continually decreasing. By Davies
GutserT, Esq., F.R.S., &e. (with a Plate) . - 90

XIV. Proceedings of the Royal Society - : - - . 104
XV. Proceedings of the Horticultural Society sine y tee a
XVI. ANALYsis OF Screntiric Books.

A Comparative Estimate of the Mineral and Mosaical Geolo-
gies. By GraNviLLE Penn, Esq. - c : : 27 108

XVII. AstronomicaL and Nauricat CoLLecTions.
i. Empirical Elements of a Table of Refraction: computed from
Observations communicated and reduced by StePHEN Groom-

BRIDGR, Esq,, F.R.S. . . B 128
ii. Errors of the Lunar Tables for 1819 <h 1820. aucune
from the Observations made at Greenwich 2 ‘ pees | 1!

iii. Mr. RumKER’s re-discovery of Enexe's Triennial ae 132
iv. Predicted and observed Places of the Principal Stars. By
Joun Ponp, Esq., F.R.S., Astronomer Royal . q eee

XVIII. MisceLuANeous INTELLIGENCE.

I. Mecnawicat SCIENCE.

1. Economical Bridge. 2. Hydraulic Instrument for raising
Water. 3. Hydroparabolic Mirror. Standard Measure. 4. Feed-
ing of Engine Boilers. 5. Improved Printing. 6. Casting of
Stereotype-Plates, by M. Didot. 7. Calculating Engine. 8. Eng-
lish Opium. 9. British Indigo. 10. Preservation of Grain, &c.,
from Mice. 11. Preservation of Turnips. 12. Yeast. 13. Pre-
vention of Dry Ret. 14. Paste. 15. Improved Glaze for Red
Ware. 16. Soldering Sheet Iron. 17. New Form of the Voltaic
Apparatus. 18. Patent Portable Static Lamp. s 186

CONTENTS, ‘ iil

ART. PAGE
II, Cuemicat Science.

1. On the Action of Heat and Pressure on certain Fluids. By
M. le Baron Cogniard de la Tour. 2. Berthier on Sulphurets
produced from Sulphates. 3. On Compounds of Nickel, by J. L.
Lassaigne. 4. On Indigo, Cerulin, Phenicin, &c., by Mr. Crum.
5. Robiquet on Volatile Oil of Bitter Almonds. 6. Action of Ani-
mal Charcoal in the Refining of Sugar. 7. Refining, or toughening
of Copper. 8. Action of Ammoniacal Gas on Copper. 9. Esti-
mation of Carbonic Acid in Mineral Waters. 10. Plumbago in
Coal-gas Retorts. 11. Test of the Dryness of Air or Gases. 12.
Variation of Thermometers. 13. Blue Iris Test Colour. 14,
Succinic Acid in Turpentine. 15. Cinnabar. 16. Dobereiner’s
Apparatus for making Extracts. 17. Heat from Friction of a Solid
and Fluid. 18. Condensation of Carbonic Acid and other Gases
into Liquids. 19. Electricity of a Cat. 209. Magnetism of Solar
Rays. 21. Inflammation of Powder under Water . : - 14

ILL, Natura History.

1. Gnthe Ascent of Clouds in the Atmosphere, by M. Fresnel.
2. Mrolite of Espinal. 3. Large Meteor. 4. Fall of Rain in the
Tropics. 5. New Comet. 6. Analysis of Uranite. 7. Native
Phosphate of Alumina. 8. Crystallized Stalactitic Quartz. 9.
Ammonia in Lava. 10. Muriate of Ammonia from Coal Strata.
11. Waters of Carlsbad. 12. On the Flowers of the Meadow Saf-
fron. 13. Return of Captain Laing from the Solima Territory, in
Africa. 14. Hauy’s Collection of Minerals. 15. Organic Re-
mains. 16. Change of Water at Falls. 17. New Species of Fungi.
18. Preservation of Echini, Asteriez, Crabs, &c. 19. African
Geography. . A . . : - 4 5 ° = 165

XIX. Meteorological Diary for the Months of December, 1822,
and January and February, 1823 . F y : 174

TO OUR READERS AND CORRESPONDENTS.

The serious inconvenience and delay occasioned in the printing of
this Journal, by allowing private copies of particular papers to be
struck off for their respective authors, obliges us very reluctantly to
announce to our correspondents, the absolute necessity of discontinuing
that practice in future.

iv NOTICE TO READERS AND CORRESPONDENTS.

We are much indebted to our ‘‘ Onp CorresponDENT” for his ob-
servations on Electro-magnetism, but he is evidently unacquainted with
all that Oersted has achieved in this department of science. Palmam
qui meruit, ferat.

F. R. S. has reached us, but we cannot, either directly or indirectly,
interfere in the subject of his letter.

We are much flattered by the proposal.of a “ PRopRIETOR OF THE
Lonpon InstTiTuTION,” but cannot afford the space which his plan
would require.

The Letter of “‘ BipLiopHiius,” respecting the destination of the
King’s Library, reached us too late for insertion, and we fear that, be-
fore our next publication, its doom will be fixed. Should the subject
not fall into abler hands, which we hope it will, we shall, upon a future
occasion, offer a few remarks upon his proposal for a National Museum.

In consequence of the extent of several papers in this Number hay-
ing exceeded our expectation, we have been obliged to omit the article
on the Progress of Foreign Science, and have incorporated the most
important parts of it with the Miscellaneous Intelligence.

On referring to the Notice to Correspondents, prefixed to our Twen-
ty-Seventh Number, Mr. Jonn Rerp will find that he has entirely
mistaken our motives for withholding his paper. We have now dis-
posed of it according to his directions.

The communication from Birmingham we have again been obliged
to postpone, in consequence of want of room for the plate. If the
author wishes it returned, it shall be left for him at Mr. Murray's.

We are sorry to decline the communication, signed S. Perhaps the
author will see our motive in an article in the present Number. His
paper is preserved, and shall be disposed of as he may direct.

B. N. D. must excuse us.

“ ELEcTRO-MAGNETICUS ” requires some consideration. We shall
endeavour to reply to him in our next Number.

If our Correspondent at Rouen will refer to Sir H. Davy's paper,
“On the Fallacy of the Experiments in which Water is said to have
been formed by the Decomposition of Chlorine,” in the Phil. Trans.
for 1818, he will find answers to all his queries.

Several papers have reached us too late for insertion, and will be
disposed of according to the notice in our last Number. As we only
publish quarterly, many subjects of temporary interest, which our Cor-
respondents are kind enough to communicate, are thus rendered useless.
This is especially the case with Mr. SuTHERLAND's paper, which was
only received last night—March 25.

CONTENTS

OF

THE QUARTERLY JOURNAL,

N°. XXX.

ART. PAGE
I. An Account of the Eruption of Vesuvius, in October, 1822.
By G. Pouterr Scroops, Esq. (With a Plate). : 175

IJ. On Mineral Veins. By J. Mac Cutxocn, M.D.,F.R.S. 183

III. Description of the Great Bandana Gallery, in the Turkey Red
Factory of Messrs. Mon rerrH and Co., at Glasgow . 209

IV. Lamarck's Genera of Shells. (With Plates). 5 : 216

V. Onthe Native Country of the Wild Potato, with an Account
of its Culture in the Garden of the Horticultural Society ; and
Observations on the Importance of obtaining improved Va-

rieties of the cultivated Plants. By Josepn Sapine, Esq.
F.R.S., &e. . 3 £ i 2 ! a , 259

VI. Observations on the Project of taking down and rebuilding
London Bridge. f - : 2 4 y 267

VIL. Estimate of the Force of Explosion of Coal Gas ; laid before
the Committee of the Royal Society inthe year 1814 . 278

VIII. On the Crystalline Forms of Artificial Salts. By M. Levy.
Communicated by the Author Be Be) Loe

{X. Historical Statements respecting Electro-Magnetic Rotation.

By M. Farapay, Chemical Assistant in the Royal Institu-

tion ; ; : : . : 7 2 ° - 288
X. Proceedings of the Royal Society . . , eplizeat) ee

XI. ProGress or Foreign Science : : : - 294

CONTENTS.

ART, PAGE

XII. ANALYsIS OF SciENTIFIC Books.

i. An Elementary Introduction to the Knowledge of Minera-
logy ; comprising some Account of the Characters and Elements
of Minerals ; Explanations of Terms in common use ; Description
of Minerals, with Accounts of the Places and Circumstances in
which they are found ; and especially the Localities of British Mi-
nerals. By Witi14m Puiuips, F.L.S., M.G.S., L. and C., &c.
Third Edition, enlarged * 3

ii. Traité Elémentaire de Réactifs, leurs Preparations, leurs
Emplois speciaux, et leurs applications AI Analyse. Par MM.
A. Payen, Manufacturier ; et A. CHEVALLIER, Paris, 1822. Svo.
pp. 224 ! ‘ : 4 : : .

iii. Reliquie Diluviane ; or, Observations on the Organic Re-
mains contained in Caves, Fissures, and Diluvial Gravel ; and on
other geological Phenomena attesting the Action of an Universal
Deluge. By the Rev. Witt1am Buckianp, B.D., F.R.S., &c.

Letter to the Editor, on Penn's “‘ Comparative Estimate”

320

326

337
348

XIII. Astronomicat and Nauticat Cottections. No. XIV.

i. The resistance of the Air, determined from Captain Karer’s
Experiments on the Pendulum.—ii. Extract from a Letter to Pro-
fessor Schumacher, relating to Bessex’s Refractions.—iii. Speci-
men of Mr, Srockier’s Inverse Method of Limits. In a Letter
to Cuartes Baxspace, Esq. F.R.S.—iv. An easy Method of
computing the Time of Conjunction in Right Ascension from an
observed OccuLTaTioN.—v. Remarks of Mr. Pianta’s Re-
searches relating to Refraction. In a Letter to Professor Gautier

XIV. MIscELLANEOUS INTELLIGENCE.

I. MecuanicaL ScreNcE.

1. Bridge at Menai Straits. 2. Gas Lighting. 3. Artificial
Formation of Haloes. 4. On the Electricity produced by Pres-
sure. 5. Light evolved by Pressure. 6. Developement of Elec-
tricity by two pieces of the same Metal. 7. Variation of Ther-
mometers. §. Variation of Thermometers. 9. On Variations of
Barometers and Thermometers. 10. Maximum density of Water.
11. Tenacity of Iron Wire. 12. Electro-Magnetism. 13. On
the Oscillations of Sonorous Chords

367

CONTENTS.

ART. PAGE

II. CHemicat ScreNcE.

1. A new Fluid discovered in Minerals. 2. Crystallized Deposit
in the Essential Oil of Bitter Almonds. 3. On a new Compound
of Iodine. Iodide of Carbon? 4, Triple Compounds of Chlorine.
5. Action of Chlorine on Muriate of Iron, &c. 6. On the prepara-
tion of Potassium and Sodium. 7. Preparation of Hydrocyanic
Acid. 8. Production of Cyanurets. 9. Iodide of Nitrogen. 10.
Thenard’s Blue. 11. On a Per-sulphate of Iron and Ammonia.
12. Test for Proto-salts of Iron. 13. Test for Barytes and Stron-
tia. 14, Action of Phosphorus on Water. 15. Fixedness of
Sulphuric Acid. 16. Effect of a Vacuum on Alkaline Carbonates.
17. Formation of a Calcareous Spar. 18. Action of Animal Char-
coal on Lime. 19. Bizio on Virgin Wax. 20, Separation of
Elaine from Oils. 21. On the Clarification of Wine

Ill. Narurau History.

1. Blumenbach on [rritability of the Tongue. 2. Sensation
experienced at Great Altitudes. 3, On the Action of Nitrogen in
the process of Respiration. 4, Diabetes. 5. Toad in a solid
Rock. 6. On the Sensitive Plant. 7. Vegetation in Atmospheres
of different densities. §. Fruit Trees. 9. Mesotype from Mount
Vesuvius. 10. Native Sulphate of Iron and Alumina. 11. Bitu-
men in Minerals. 12. Italian Marble. 13. Bagne Lake and
Glacier. 14, On the Theory of Falling Stars. 15. Preservation
of Anatomical Preparations : : :

XV. Meteorological Diary, for the Months of March, April, and
May, 1823 - - : :

Index

375

385

392

393

TO OUR READERS AND CORRESPONDENTS.

Mr. Vulliamy’s paper on the Theory of the Dead Escapement, will
appear, with its illustrative plates, in our next Number.

Mr. Johnstone's ‘ Analytical Inquiries into the Nature of Nitrogen
and Ammonia,” reached us too late for insertion ; the paper, therefore,
is disposed of according to his directions,

We have received the ‘‘ Edinburgh Critic ;* but his remarks appear
to us very irrelevant.

A Member of the Apothecaries' Company is informed that we shall
probably give some account of the New Laboratory, and of the mode
of conducting business in it, in our next Number.

A Correspondent, who writes to us upon the subject of Gas Works,
and signs himself ‘‘ Anti-Alarmist,” is too voluminous, even for a
Quarterly Journal.

We must decline all interference upon the subject of Mr. W. C,'s
Letter.

Mr. Wrangham’s paper shall appear in our October Number, pro-
vided he has no objection to its standing over till that time.

We recommend a little more circumspection to our Correspondent,
who calls himself a ‘‘ Practical Chemist.” The Numbers in our Table
of Equivalents to which he alludes, are any thing but theoretical, and
are deduced, in all cases, from the eaperiments of others, or from ori-
ginal ones of our own, The number for gold with which he particu-
larly quarrels, happens to be deduced from the analysis of the insoluble
iodide, and as it closely corresponds with that derived from an analysis
of the triple chloride of gold and potassium by Berzelius, we had no
hesitation in adopting it. We cannot help its slight disagreement with
the experiments of MM. Pelletier, Oberkampf, $c. Had we entered
into all our experimental details and data, we must have written a
volume.

NEW WORKS PREPARING FOR PUBLICATION.

Essays on Meteorology, by J. F. Daniell, Esq., F.R.S. 1 vol. Svo.
A System of Mineralogy, by J. Mac Culloch, M.D., F.R.S.
A Manual of Pharmacy, by W. T. Brande, F.R.S. 1 vol. Svo.

ERRATUM.

In Mr. Davies Gilbert’s paper “ On the Vibrations of Heavy Bodies,’ the first two lines
in page 97, should follow the Table, page 103.

THE

QUARTERLY JOURNAL,

April, 1823.

Art. I. On the Curvature of the Arches of the Bridge of
the Holy Trinity at Florence. By Samurn Ware,
Esq.

[To the Epiror of the Quarterly Journal of Science and the Arts.]

To determine the curvature of the arches of the marble *
bridge of the Most Holy Trinity erected over the Arno at
Florence by Bartolommeo Ammanati, is a problem which still
occupies the attention of antiquaries, mathematicians, and ar-
chitects. Some account of the interest this question has ex-
cited, will be found in Ferroni’s tract entitled “ Della vera curva
degli archi del Ponte a S. Trinita di Firenze ; discorso geome-
trico-storico,’”’ inserted in the 14th vol. of the Transactions of
the Societd Italiana delle Scienze.

When it is observed, that the curvature of these arches affords
the flattest roadway, and the greatest waterway, with the
smallest quantity of material of any stone bridge ever con-
structed, and taking into consideration that cast-iron is ten
times stronger than marble, and twelve times stronger than
common stone in compression, and that the vault of this bridge

* This bridge is only faced with marble, the vault between the faces is
built with ordinary stone, coarsely wrought, but bonded at intervals from
face to face, by stone of a better sort properly worked.

Vou. XV. B

2 Mr. Ware on the Curvature of the

is less in depth from the intrados to the extrados, than any iron
bridge hitherto built, with relation to the radius of curvature at
the vertex*; we shall not wonder that the inquiry should be
continued until a satisfactory solution be obtained. The fol-
lowing attempt to solve this question has been made, in the
hope of rendering so excellent a bridge more generally known
than it is at present, and to mark it as an object for imitation,
now that it is in contemplation to erect a new bridge in the place
of London Bridge. Perhaps the inquiry may cause hereafter
some proper applications of geometry and known formule to
be made to elliptical curves, of which, judging from the arches
of this kind which are to be seen in very conspicuous places
in London,—modern builders appear to be unacquainted with.
The historical inquiries of antiquaries have been suspended, for
they cannot find in the memoranda of Parigi any account of the
nature of the curve, nor trace the lost manuscript work of Am-
manati, entitled La Citta, beyond the possession of the Great
Prince Ferdinand of Tuscany. Mathematicians to the time of
’ Ferroni, contented themselves principally with conjectures de-
rived from the resemblance of the curves of the arches of this
bridge to other curves, sometimes concluding them to be com-
posed of arcs of circles of different radii, at other times ellipses,
parabolas, or catenaries. Some more industrious have measured
the arches by taking ordinates, or various triangles, with such
implements as lines and tapes. But as the absolute curve had
not been accurately obtained before Ferroni’s time, consequently
the curve of Ammanati could not be satisfactorily deduced.
Ferroni employed in 1785, Joseph Salvetti, to measure correctly
the middle arch of this bridge by ordinates at each braccio, and
he states proper implements were provided, and that the ordi-
nates were measured twice over; different measurements have
since been published, but not such as to cause any doubt to be
entertained of Salvetti’s accuracy. Ferroni having thus ob-
tained the clew, he found the labour of unwinding it more irk-

* In the Ency. Méth. Arch, Art., Ammanati. This bridge is thus de-
scribed: ‘‘ Son goiit, sa hardiesse, et sa légéreté, le font passer pour le plus
beau de l’architecture moderne.”

Arches of the Bridge of the Holy Trinity. 3

some than invention: he therefore assumed the curve to be a
scheme, and having placed together six arcs of circles approxi-
mating to the curve, concluded that he had found out the curve
itself. He was led to such a proceeding by the example of
modern French architects, who are very ingenious in coaxing -
ares of circles into an approximation to a continued curve which
they call anses de panier, as substitutes for regular curves, in
order to evade a little trouble in setting out the voussoirs of
arches, (not arcs of circles,) or from not knowing the method
of doing it.
The accompanying drawing, CEG., Fig. 1. of the curve of the
middle arch is correctly drawn to Salvetti’s ordinates, to a scale
_of Florentine braccia *, and is manifestly a Gothic pointed arch
of the time of Henry VII. In the beginning of the reign of
Henry VIII, Torregiano + came to England from Florence to
erect the tomb of Henry VII, he returned also to Flerence as
Cellini relates, to engage several youths to assist him, and he
finished the tomb in 1519. During his stay in England, the
chapels of St. George, Windsor, of Henry VII, Westminster,
and of King’s College, Cambridge, were in progress; in which
buildings, arches, similar to that of the bridge of Ammanati,
had been partially introduced as principal arches, and it is pro-
hable from the novelty of their appearance in such situations,
that the form attracted the attention of Torregiano and his
pupils, and by them it was introduced at Florence to the notice
of artists, among whom, in 1526, Ammanati { must have been
a student. The fitness of this curve § to the Bridge of S. Trinitd
induced Ammanati in 1566, to adopt it, though a Gothic curve;
but obedient to the prevailing taste, he dressed it in the then
fashionable costume of Roman architecture; but the ornaments
at the vertices of the arches, seem intended only to veil his ob-

* A braccio is divided into 20 soldi, a soldo into 12 danari. A braccio
= 1.9 feet English. See Dr. Young’s Lectures on Natural Philosophy.

+ Vol. I, page 162, Walpole’s Anec. of Painting.

¢ See Malizia Memorie degli Architetti.

§ Ferroni says, before the time of Ammanati, there is no example of such
an arch.

B 2

4 Mr. Ware on the Curvature of the

ligations to Gothic science, not like the skreen wall of St. Paul’s
Cathedral, to conceal those of Sir C. Wren.

During the time that vaults were erected over ecclesiastical
buildings, arches of this kind, being nothing more than elongated
pointed arches, or arcs of ellipses, would have been obtained
in the following manner. Draw aright angled triangle, ABC,
and divide the hypothenuse and one of the sides AB. each into
an equal number of parts proportionally. Upon AB. describe a
quadrant of a circle, and at right angles through the points of
division, draw the semichords, which transfer to the correspond-
ing points of division in the hypothenuse, as an absciss for or-
dinates, hence the curve CEG required; the directions of any
joint E of two voussoirs, would be obtained thus,—with the
vertex V of the curve so obtained as a centre, and radius equal
to the hypothenuse BC, cut the hypothenuse BC, continued in F
andf; draw the right lines EF and E f, and bisect the angle
FEf, the line of bisection is, the direction of the joint required.
In the works which are published of Gothic architecture, it is
assumed that arches of this character are, in ancient buildings,
composed of arcs of circles, but arches so generated only
characterize and betray modern imitations, and oftentimes the
restorations of Gothic architecture of the time of Henry VII.
There may possibly be in some ancient building, examples of
such mis-shapen arches, but I have not been able to find among
the numerous publications of Gothic architecture, any such arch
drawn from ordinates, to confirm such conclusions. It is mani-
fest that the diagonal ribs in Gothic groined vaulting, must be
arcs of ellipses; and if there be any examples of the corrupt
practice before mentioned in this country, they are of a later
date, when Gothic architecture had declined.

If the curve obtained by Salvetti be tried in a few cases with
the given ordinates and abscisses by the common formula Y=,
when y = the ordinate, x = the absciss, and p = the para-
meter of a parabola, it will be manifest that it is not a parabola.

fe)
In like manner by the formula fog fepe, AS, FO u%
sec. @ ver. sin. Q. mx

Arches of the Bridge of the Holy Trinity. 5

when ¢ denotes the angle of the curve with its ordinate, and
m = 2.302585 to find 9 by approximation, and thence the

é x
constant quantity = ———
’ Y= Sec. g—1,

tained, whether it was designed to be a catenary, for in five
cases by calculation, the longest constant quantity was 2.59,
and shortest 2.46.

It may be observed that if the curve had been an arc of a
parabola or of a catenary, curves likely to be adopted at the
time of the erection of this bridge, from the inquiries then com-
menced respecting them, that the ordinate in the middle of the
arch, as well as the absciss, would have been whole numbers,
and the same conclusion will be come to, if it had been a scheme
as Ferroni supposes. But in adopting an ellipse for the curve,
it may be presumed that the axes and the span would have been
integers, and the height fractional, dependent on them.

some doubt may be enter-

In trying whether the curve be elliptical, we must assume one
of the axes.’ It is a reasonable presumption to conclude from
the obtuseness of the angle at the intersection of the arcs, that
the semi-conjugate axis was taken, the next greatest whole
number to 7 16 6, the ordinate in the middle of the arch, that
is, eight braccia. Let x = the absciss, y = the corresponding
ordinate, c = the semi-conjugate, and t = the semi-transverse.

Then by the common formula t = ae + + (c2 -y:)} = a2

nearly. Hence we derive an ellipse whose semi-conjugate axis
is 8, = ith of the transverse axis *.
If now we take t= 32 braccia, and c = 8 braccia, and then

by the common formula y = : J (2xt — x2) we may obtain

ordinates by calculation to compare with Salvetti’s.
When x = 2, then y by calculation, = 2 15 9, by measurement,2 19 2,

Gi snk aaah thst S SSE S SAY CAN Rais,
pity, ce eta en aton or Aig hy pata
BO aie te GWA AE lod De Uvioaiyb cue 10;

* Ferroni lays great stress upon Ammanati’s prepossessfon for dimensions
of which 8 is an aliquot part.

6 Mr. Ware on the Curvature of the

Whenx= 12 then y by calculation, = OTD 0, by measurement, 6 4 4,
Tord wottaivetin GOlg Hee’ ah esa hang,
7 RAIS FCM ES NOLL RH PRGA AAD,
Be et ee ee Fea ie ati)
DBeiahates ee hoy BAe hy 1s a aes,

By referring to the mode of framing the centering according
to the drawing left by Parigi, it will be observed that the strutts
abut against King posts, and not against each other as they
should have done; and by supposing, as happened lately in this
metropolis in a similar case, that the masons proceeded to lay
the voussoirs from the imposts towards the key, without ba-
lancing by weights, the other parts of the centering, the little
variation, (too small to be seen to the scale of the diagram,
Fig. 1,)elicited by comparing these results, may be satisfactorily
accounted for.

These dimensions shew that the arch has sunk at the haunches
between the ordinates 9 and 20, and risen at the springing and
crown, presuming the curve to be elliptical as deduced. It may
be concluded, upon a balance of evidence, notwithstanding the
approximation of the present curve of the middle arch to a cate-
nary, that the curve was intended to be an arc of an ellipse,
whose transverse axis is 64 braccia in length, and whose semi-
conjugate is 8 braccia. The properties of the ellipse, necessary
to the setting out an elliptical rib, during the time the vaults of
ecclesiastical buildings were erected, were as familiar to the
commonest mason, as they are to every millwright by the prac-
tice of his trade. Mr. Rennie has, by the adoption of the conic
section at Waterloo Bridge, probably by the accident of his
early habits and extensive business as a millwright, made a
great stride beyond his contemporaries, and acquired much
honour for himself and his country, and availing himself of the
lavish means afforded, he has maintained the unities of dress
and form, without requiring a veil like Ammanati, or a skreen
like Sir C. Wren.

The principal dimensions of this bridge are written on the
small drawing of it, (Fig. 2,) in Florentine braccia, taken from
Ferroni. It remains to be observed that the depth of the archi-

Arches of the Bridge of the Holy Trinity. 7

volt was intended to be, according to Parigi, one braccio and a
half, that the depth of the arch at the crown was intended to be
one braccio and a quarter, the span of the middle arch was in-
tended to be, as it is, viz., 50.braccia, and of each side arch
was intended to be 45 braccia. The radius of curvature
Ti ait Bites B. 8. D.

pointed elliptical arch, the ordinate = y = 7 16 6, the trans-
verse = t e= 64, and the conjugate = c = 16; so that this
arch ranks with a pointed arch, (the angle of intersection of the
ares as after shewn, being = 173° 34’,) composed of two ares of
a circle whose radius would be (120 x 1.9 =) 228 feet English,
and the span (456 — 26 in whole numbers, the chord of an arch
of the same circle of 6° 26’, =) 430 feet, the thickness at the
240 x4

5
of such circle. The angle made by the curve with its ordinate
atany point, may be obtained as follows : let s denote the sub-
tangent, and y and x as before, and t = the semi-transverse, then
2tx — x? "
rt and by trigonometry,

= a the 192nd part of the diameter

vertex being (

by the known formula,s =

s apd nies
the tangent of the angle = 7 which in the case of the vertex,

gives by a table of natural tangents, the angle 86° 47’, or the
angle made by the intersection of the two arcs, 173° 34’.
Ferroni makes it for his scheme, 174° 4’. In the case of a
catenary, the angle would be 169° 22’. Ferroni gives only
the middle ordinate = 7 3 5, of one of the side arches and
the spans of them; he has not invented a scheme to fit the
curves. By referring to the ordinates given by him of the
middle arch, it appears that the curves of the side arches must
be ares of an ellipse, (assuming the curves elliptical,) of which
the semi-conjugate axis bears a less proportion to the transverse
axis, than in the case of the middle arch. If we take again
c = 8, and a = 22}, as intended by Ammanati, we have the

an
semi-transverse = ¢ = mt + J (c? — ys} = 40. Hence

8 On the Bridge of the Holy Trinity.

we derive an ellipse whose semi-conjugate axis is 2, = jth of
the transverse axis; from which we may obtain the ordinates by
construction by Fig. 1, or by calculation as before; the angle
formed by the intersection of the curves at the vertices of the
side arches, will be 169°, 44’, according to the formule before
given.

Fig. 3. The semi-span of the pointed circular arch in the
case of the middle arch from which the elliptical arch would be
an elongation (when r = the radius = 8, and the height = ¢ =
7\606,).will bes2r—4fo page = 616.8.

Fig. 4. Inthe case of the | side arches, the semi-span will be
B-

49 £ the height being 7 3 6.

Arr. II. A History of a painful and obstinate Affection
of the Brain, which ultimately yielded to the unremitting
Application of Cold, and the continued erect Position for
aweek. By G.D. Yeats, M.D., F.R.S., Fellow of
the Royal College of Physicians, &c.

{In a Letter to the Editor.]
Dear Sir,
I request the insertion of the following case in your Journal.
{t illustrates, in a clear point of view, the good practical
effect of the application of cold, assisted by position, in obviat~
ing and ultimately curing the painful and dangerous conse~
quences of congestion of blood within the cranium, after th®
failure of other very active means; and this morbid condition of
the brain succeeded to, and was connected with, a long-con-
tinued irritation in the digestive organs.
I am, dear Sir,
Yours faithfully,
17, Queen-street, G. D. Yeats:
May Fair, Feb. 16, 1823.

I was consulted by H J——, Esq., aged 40, on the
14th February, 1819. He complained of general uneasiness, not

Dr. Yeats on an Affection of the Brain. 9

easily defined, in the region of the stomach, with a languid and
sinking feel there. The tongue exhibited that furred and
clammy appearance common in disturbed digestion; the appe-
tite was not impaired, but he felt uneasy after his meals, which
induced him to indulge in wine at dinner, as the stimulus of it
gave temporary relief; he was troubled with frequent headachs.
The bowels were costive, and very irregular in their movements,
a properly-figured evacuation being seldom passed, and the
passing the contents of the intestines caused uneasy sensations
of fulness about the head ; the feeces were likewise very morbid
in appearance. The urine was not much altered in quality
or quantity ; the pulse did not particularly indicate disease.
On examining the abdomen, no fulness was perceptible, but a
soreness was complained of, and some hardness felt on pres-
sure on the right side, in the region of the liver. He had be-
come considerably thinner, and had suffered from the above
complaints fora long time, and had taken the advice of several
professional gentlemen. By attending to the condition of
the lower intestines and digestive organs, with the proper
evacuants and alteratives, more comfortable sensations were
acquired there ;_ but the head now principally arrested attention
on account of the great uneasiness complained of in it, which
rendered it necessary to have recourse to the local detraction
of blood, and to a constant soluble state of the bowels, by
cooling laxatives, and a restricted diet. He left town in March,
on professional business at Cambridge.

May 5.—Up to this day I had seen Mr. J two or
three times after his return to town. He had been cupped,
and bled, and blistered, before and since I saw him, and
his bowels had been attended to by evacuants, with very
little relief to the affection of the head, beyond some temporary
ease, and sometimes without this. At this date, May 5, 1819,
the affection of the head had evidently increased; the pulse
had become somewhat quicker and harder, and he described
the distress in his head in the following manner :—A pain,
with heat, would commence in the back part of it, deep seated,
and would be diffused gradually throughout the whole of the

10 Dr. Yeats on un Affection of the Brain.

-back part of the brain, which would continue sometimes for
two hours, causing insufferable distress within the scull, but
confined, as it would seem, to the cerebellum, as the crown and
fore-part of the head were not affected. A horizontal position
increased this suffering, and it was most acute about three or
four o’clock in the morning, after he had slept for some hours.
He felt considerable giddiness and confusion in his head when
he stooped upon any occasion. The symptoms evidently
indicated bleeding, but he would not submit to it in any way,
from the failure jof these means to procure relief on former
occasions. His sufferings and his danger, too, being now
greatly multiplied, he submitted, after much persuasion, to the
following plan :

At my request a seton was inserted in the neck, by Sir Astley
Cooper. Mr. J. was confined entirely to vegetable and fari-
naceous food ; barley-water, rennet whey, and such like, being
his only beverage, and he was desired to keep continually in
the erect position with his body, by sitting in a chair, not going
to bed at all, and to keep his head, which had been shaved for
the purpose, unremittingly moistened with a cold lotion (a so-
lution of muriate of ammonia, in vinegar and water). I put
him upon this plan from the idea that the blood did not readily
find an exit from the head, in the tortuous and complex circu-
lation of the brain, in the horizontal position; and, 2dly, the
veins of the brain had become weakened, from the long state
of distention in which they had existed; they had not, there-
fore, sufficient power to propel their contents against gravity,
while the body was in the recumbent position, which, at the
same time, favoured the transmission of the blood to the head by
the arteries; thus there was a supply, without a corresponding
discharge. The erect position facilitated the return of blood from
the head, while it assisted to impede its progress thither, and
the coldness of the lotion gave a contractile power to the veins,
diminished their calibre, thus accelerated the transit of the
returning blood, and prevented the accumulation and the con-
sequent pain.

The happy practical effect fully confirmed the soundness of

Dr. Yeats on an Affection of the Brain. 11

the doctrine. From the ease which this plan very speedily
produced, Mr. J. very readily submitted to a perseverance in
it, and for one whole week he never once lay in a horizontal
position, and the application of the lotion to the head was never
omitted during the whole of that time. He occasionally walked
about the room for relief. At the end of the week he was so
much better that the plan was gradually omitted ; and the best
symptom of amendment was, that he was able to sleep hori-
zontally, awaking without pain. I am well aware of the ex-
cellent effects of the application of cold in that excited state of
the brain; which in children and others so often ends in effusion
of fluid there, but I do not recollect to have met with so long
continued and obstinate a pain within the head, connected, too,
with such great derangement in the digestive organs, in which
the erect position, with cold applications, was so long’persevered
in, and with such decided and permanent benefit. The seton
was not withdrawn till the 6th of July, a period of two months
from its first insertion. The only medicines taken were, a solution
of the supertartrate of potash as a diuretic (to obviate the accumu-
lation of fluid in the brain, for in almost all cases of severe af-
fections of this organ, more or less of effusion of fluid takes
place,) and occasional purgatives when necessary. ‘This gen-
tleman remained free from his complaint up to last year, since
which time I have not heard of him.

Art. III. An Account of the Rock Specimens collected
by Cartain Parry, during the Northern Voyage
of Discovery, performed in the Years 1819 and 1820.
By Cuarues Konie, Esq., F.R.S., &c.

[To the Evrtor of the Quarterly Journal of Science and the Arts.]

British Museum.
My pear Sir, Feb. 18th, 1823.

I have great pleasure in transmitting to you the short account
I have been desired to write of the rock specimens, which were

12 Mr. Konig on the Rock Specimens

collected during the voyage performed by Captain Parry in the
years 1819-20. It was drawn up from rather slender mate-
rials, immediately after the return of the Expedition. Although
I am fully sensible of the little value of desultory remarks made
under such circumstances, yet I think that the interest, insepa-
rable from every the smallest communication connected with
those most important investigations, that have been and are
still carrying on in the polar seas by that enterprising naviga-
tor, will plead your apology as well as mine, for submitting
them to the readers of the Journal of Science.

We may conclude, from the nature of the rock specimens
collected on the former voyage for discovering the North-West
Passage, that both the east and west coast of Davis’ Strait and
Baffin’s Bay are composed of primitive formations, in con-
nexion with others of a more recent date, which for the greatest:
part belong to several members of Werner’s trap formation. It
would appear, however, from the paucity of specimens decidedly
referable to trap rocks among those brought from Baftin’s Bay
by the late Expedition to the Arctic Seas, that the same forma-
tion is less prevalent on the western coast. While on the west
coast of Greenland it exists in all its different gradations, but
more particularly in the form of amygdaloidal transition trap,
with many of those minerals which are usually found nidulating
in it, such as calcedony, agate, jasper, green earth, §c., no
traces of any of these substances are seen among the specimens”
collected by the Expedition in its progress down the western
coast of Baffin’s Bay, where the principal rocks are gneiss and
micaceous quartz-rock, with some ambiguous granitic compound,
in which hornblende seems to enter as a subordinate ingredient,

In the latitude of the entrance into Sir John Lancaster’s
Sound, the specimens which I had an opportunity of seeing,
begin to indicate the predominance of older traps, with other
concomitant transition rocks. Among them the more promi-
nent are fragments (many indeed only detached from boulders,)
of well-defined syenite, with red, and others with greenish-grey
feldspar, the latter approaching to compact in its texture,
Epidote, which is frequently seen in this syenite, has in some

collected by Captain Parry. 13

specimens the appearance of being one of the constituent in-
gredients of the rock. Other masses from Possession Bay, are
hornblende rock, with disseminated garnets; greenstone, ap-
parently primitive, and a greenish grey sandstone more or less
impregnated with oxide of iron. There are a few other varieties
of sandstone, one of which, more or less streaked with reddish-
brown, has all the characters of and may possibly belong to
the bunt-sandstein of Werner ; especially as there are accompa-
nying specimens of fibrous and fletz-gypsum, which formation
is generally found with and resting upon the second or varie-
gated sandstone, and is often overlaid by shell limestone.
Of this last-mentioned variety of fletz limestone, there is a
specimen among those collected in the valley of Possession
Bay, by Mr. Fisher. This gentleman, it is observed, found
that valley to consist partly of basalt; but I have not seen any
specimens of this rock among the fragments obtained in that
place. The other rocks from that quarter which have fallen
under my observation, are chiefly primitive, viz., granite, gneiss,
and some mica slate, with hornblende and quartz rock. They
exhibit nothing new or remarkable in their oryctognostic cha-
racter. The several varieties of granite differ from each other
only in the varying proportion of the usual component parts,
in their grain and colour. Both the gneiss and mica slate
contain small imbedded garnets, and to the latter of these may
be referred a micaceous mass, enclosing grains and amorphous
masses of noble garnet, intermixed with a yellowish white
substance, which seems to be compact feldspar. Another
substance from Possession Bay which deserves to be noticed, is
a variety of fibrous limestone, not inferior in lustre, when
polished, to the satin spar of Cumberland.

Compared with these rock specimens from the western coast
of Baffin’s Bay, those gathered on the coasts where Captain
Parry’s discoveries commenced, seem to indicate a considerable
difference in the respective geological features of those tracts.
The north coast of Barrow’s Strait, as far westward as the
Polar Sea, and part of the eastern coast of Prince Regent’s
Inlet, appear to exhibit a character belonging to those more

i4 Mr. Konig on the Rock Specimens

recent formations which are known to proceed from the primi-
tive mountains of Scandinavia, and other explored tracts of
high northern latitudes. Among them a variety of limestone
seems to prevail, which is very like the Alpine or mountain
limestone. It is compact, of yellowish and greyish colour, and
contains, among other remains of zoophytes and shells, abun-
dance of the same species of Terebratula, which are charac-
teristic of that rock in various alpine tracts in Europe. A
greyish-brown fetid variety of limestone, from the north side of
Barrow’s Strait, bears great resemblance to the mountain lime-
stone as it occurs in Derbyshire; it contains parts of coral-
lines, which are, however, too imperfect to be determined.
The chert, or hornstone, of which likewise specimens were
found in those parts, may, perhaps, occur as subordinate beds
in this transition limestone. Among the specimens from Riley
Bay, is a fragment of white granular marble passing into com-
pact.

Not less indicative of the formation to which the above-
mentioned varieties of limestone belong is a calcareous mass,
which, it would seem, abounds in various parts of the north
coast of Barrow’s Strait, on the eastern coast of Prince Regent’s
Inlet, and which also occurs on the south coast of North Georgia.
This limestone, which bears some resemblance to that of Goth-
land, in which parts of the stems of Encrini are found, is yet
sufficiently distinct from this, and all other varieties I am
acquainted with, to deserve being briefly noticed in this place.

Itis of a yellowish-white colour, and, in most hand specimens,
exhibits a uniform coarse-granular structure ; it is friable, and
the grains are indeterminately angular, more or less shining,
and sometimes intermixed with, or cemented by, calcareous
matter of a deeper yellow. Reduced to powder, it emits a
yellow phosphorescent light when strewed on a heated iron.
This calcareous rock, in some specimens from Prince Regent's
Inlet, abounds with parts of the jointed stem and single joints
of a zoophyte belonging to the natural order of Encrini; other
specimens appear to be entirely without these bodies: but on
subjecting the different varieties of aggregation to a closer

collected by Captain Parry. 15

examination, it will be found that those which contain no re-
mains manifestly belonging to the just mentioned organized
fossil bodies, are, nevertheless, entirely composed of their
detritus. This encrinitic mass, in single specimens, might
readily be mistaken for a friable variety of common granular
limestone, did not a comparison of a series of specimens prove
that appearance to be produced by the extreme comminution
of the substance of those fossil zoophytes, each particle of
which still exhibits planes of cleavage parallel to the primitive
thombohedron.

The joints of the stem and branches of the zoophyte which
appears to have thus largely contributed to the formation of this
mass, are mostly cylindrical; their thickness is in an inverted
ratio with that of the column of which they form parts ; those
near the body being the largest and thinnest. Cylindrical
pertions of the stem, formed by these thinner vertebre, exhibit
on their surface hemispheric concavities, some of them large
enough to occupy from four to six of the thin joints or vertebrz,
the lines of separation of which are seen to traverse the cavities
in a horizontal direction. They are the sockets of articulation,
in which the branches of the stem were inserted. The casts
produced from these concavities in the surrounding mass,
might, when seen without their moulds, be easily mistaken for
distinct organic remains. There is little doubt that this zoo-
phyte is related to some of those encrinites of which parts of
the stem and branches so frequently occur in the transition
limestone of Gothland. It seems to me also probable that many
of the screw stones (Epitonium, L.) owe their origin to the
decomposition of the stems of species belonging to this genus.

Another species of a genus of zoophytes, peculiar to the
transition limestone, was found by Captain Parry, in Prince
Regent’s Inlet, at the foot of a high hill. It is a fine Cateni-
pora, which appears to be quite distinct from the common
chain coral of Gothland, and other countries. Lamarck has
two species of this genus, namely, the common one, which is
(rather unaptly) called by him C. escharotdes; and another,
which he distinguishes by the name of C. aazllaris, though it

16 Mr. Konig on the Rock Specimens

appears from his reference to a figure in the Amenitates Acade-
mice, that he is speaking of Tuzrrora serpens, L., which is
not a congener of, and can indeed scarcely be considered as be
longing to the same natural order with Catenipora. We may,
therefore, look upon this arctic species as an undescribed and
anonymous one. I call it

Catenipora Parra: tubulis crassiusculis, compressis, col-
lectis in laminas sinuatas varie inter sese coalitas, tubulorum
orificiis ovatis seepe confluentibus : dissepimentis confertissimis.

The space between the laminz is filled up by a yellowish cal-
careous mass ; the tubes themselves are converted into carbonate
of lime, internally drused with minute crystals of the same
substance. ;

Very little can be inferred from the specimens of primitive
rocks, gathered both in Prince Regent’s Inlet and Barrow’s
Strait: they are, for the most part, fragments from rolled pieces,
and consist chiefly of granite, mica slate, and quartz rock.
There are, nevertheless, some among them, especially among
those from the first-mentioned tract, which distinctly indicate
primitive trap formation, such as granular and slate hornblende
rock, together with several varieties of syenite, and similar
rocks, in which hornblende and felspar form the predominating
ingredients; some of them enclosing massive and indistinctly
crystallized epidote of either a yellowish or grass-green colour.
Among some specimens found at Port Bowen, on the eastern
coast of Prince Regent’s Inlet, may be specified a rolled piece
of a mass, composed of flesh-red felspar, greyish-white quartz,
and asubstance which is distinct from epidote, though it might
easily be mistaken for it. According to an analysis, with which
I have been favoured by J. G. Children, Esq., it is composed of
silica 59.89, alumina 22.45, soda 6.84, lime 4.85, oxide of iron
4.0, magnesia 0.67, oxide of manganese 0.16 ;—loss 1.14. Its
specific gravity Mr. Children found to be 2.67. Before the
blow-pipe it melts into a milk-white enamel. Its colour is a
dirty yellowish green, passing into brownish. It is scratched
by the knife; streak white. Fracture uneven, dull, approach-
ing to resinous ; here and there with small planes of cleavage,

collected by Captain Parry. 17

which are shining, and even splendent. It is rather easily fran-
gible; the fragments are indeterminately angular, and translu-
cent at the edges. This substance, which I suppose constitutes
a distinct species among the silicates of sodium, appears to be
one of those which enter the composition of the rock called
Gabbro by Mr. Von Buch. |

As probably connected with this formation we may consider
the magnetic iron-stone, of which some specimens were gathered
in lat. 72° 45’, long. 90° west; it is of avery fine grain, and
occurs also disseminated in, and alternating with, granular
quartz, exhibiting white and grey stripes. Some specimens also
of jaspery ironstone mixed with particles of quartz, were found
on the eastern coast of Prince Regent’s Inlet. Nor is the pre-
sence of iron less observable in specimens referable to more
recent formations of trap from the same quarter, such as various
kinds of clay ironstone, and ferruginous sandstone. Of the
latter of these a greenish-grey variety appears to be of parti-
cularly frequent occurrence in those parts ; if we are allowed
to judge from the many, especially tabular, fragments brought
from thence, which are all, more or less, impregnated with brown
hydrous oxide of iron, some being so completely penetrated by
it that they may be considered as tolerably rich ores of this
metal.

As it is sufficiently difficult to judge of the relative antiquity
of depositions of sandstone, when observed in situ, it would, of
course, be altogether unavailing to indulge in conjectures re-
specting the formations to which the fragments and rolled pieces
may have belonged, which were picked up in various parts of
the north coast of Barrow’s Strait, and Prince Regent’s Inlet.
The most abundant among them is a red sandstone, and a va-
riegated one with brownish-red stripes. These varieties are
seen to pass into one another: they are composed of small
grains, united by a quartzy cement, and frequently confluent, so
as to forma nearly compact, hornstone-like mass, similar to the
variety of hard sandstone from Egypt, which has been often
employed in that country for purposes of statuary and architec-
ture. In external characters it agrees exactly with one of the

Vou XV. Cc

18 Mr. Konig on the Rock Specimens

oldest formations of fletz sandstone, the bunt-sandstein of
Werner; and the slaty grey sandstone, of which specimens
were found, may possibly be the sandstein-schiefer of the same
geologist, which is said to be a characteristic concomitant of
this second sandstone.

There is nothing particularly remarkable in the specimens
from Byam Martin’s Island : they are few in number, consisting
of two varieties of granite, both with bright-red feldspar, red
close-grained sandstone passing into compact, and a ferruginous
sandstone, together with small fragments of flint slate.

The rock specimens from Melville Island, though little can
be said respecting the relative situation of most of them (they
being chiefly rolled pieces, or casual fragments,) yet form a more
complete series than the others, and some of them are by no
means uninteresting. There are two or three varieties of gra-
nite, gneiss, and syenite; the latter (from Winter Harbour, and
the north shore of the island,) of a larger grain and with red
feldspar, contains much green epidote, and is very like that
which occurs in several parts of the island of Jersey*. In
another variety from Winter Harbour, which contains some dis-
seminated iron pyrites, the hornblende appears in a more com-
pact state, and in the shape of irregular veins and threads.
Another variety from the same place is rather remarkable from
its exhibiting here and there small cavities, drused by minute
quartz crystals, and coated by scaly red ironstone. In another
specimen, small grains of ironstone, attracted by the magnet,
were seen, and, upon examination, found to be titaniferous. The
few pieces of hornblende rock from this island, seem to be de-
tached from boulders found in Winter Harbour; among them
is also a specimen of a slaty compound of hornblende, mica,
and red feldspar.

The principal formation of the island appears to be the fletz
sandstone, with the subordinate one of coal and ironstone.
The structure of the cliffs along a considerable extent of the
northern shore of Barrow’s Strait, exhibiting, beside horizontal

.* See my description of it in PLets’s Account of Jersey, p. 233.

collected by Captain Parry. 19

stratification, numerous buttress-like projections and mural pre-
cipices, is not of uncommon occurrence in the formations of the
transition and older fletz lime stone; but still more striking in
this respect is the appearance of the sandstone formations,
especially those of more ancient date. Having undergone a
peculiar disintegration which acts in a direction nearly perpen-
dicular to the horizontal stratification, they exhibit the represen-
tations of ruined towers, buttresses, pillars, and similar works
raised by the hand of men. This structure, so strikingly express-
ed in the sandstone formation of Bohemia, Saxony, and other
parts of Germany, at the Cape of Good Hope, and particularly
in several mountainous tracts of China, appears no less charac-
teristic of the sandstone of some parts of the coast of Melville
Island, especially at Cape Dundas, the westernmost point to
which the investigation of Captain Parry extended, and the
general features of which have been so ably described by him
in his Journal.

This sandstone is composed of very fine, flat, confluent
grains, with here and there the appearance of minute silvery
scales, which, when more or less aggregate, communicate to the
mass a perfectly micaceous appearance. It occurs both of a
uniform greyish-white colour, and more or less marked through-
out by small brown ochry spots, which sometimes are confluent
into large patches. It generally separates into tabular pieces,
and is sometimes invested on the rifts with thin plates of white
carbonate of lime. Some of its varieties are not unlike grau-
wacke slate. It contains secondary fossils. Of the specimens
which I had an opportunity of examining, two bore the impres-
sions of a Trilobite, but too indistinct to admit of being deter-
mined with precision *,

In another yariety of sandstone, of a grey colour, found in
the neighbourhood of Table-hill, I observed some disk-shaped
bodies of about half an inch in diameter, exhibiting concentric
circles, with crenulated rays proceeding from the centre, which

* I have since determined it to belong to Brongnart’s genus of AsaPius
lately published ; but whether or not it be one of the species described by
him and Wablenberg, cannot be ascertained from the specimen alluded to.

C 2

20 Mr. Konig on the Rock Specimens

is in the form of a small knob: they are, no doubt, trochi or
joints of the stem of an Encrinus; but this is all that can be
said of them.

The two specimens of sand stone containing the above-men-
tioned secondary fossils, are pretty similar in appearance to
Ahose others brought from Melville Island, which abound with
the vegetable remains characteristic of the coal sandstone.
These are for the most part merely impressions and filmy cat*
bonaceous remnants of leaves (or fronds with ovate-lanceolaté
leaflets,) and stems, which by their regularly placed oval marks,
indicate that the prototypes belonged to the arborescent ferns
which we observe in'such great abundance in the coal sand-
stone of more southern latitudes ; a proof that the inhospitable
hyperborean region where they occur, at one time displayed the
noble scene of a luxuriant and stately vegetation. There is
also among the specimens of sandstone from the same place,
one bearing the impression of a thin, longitudinally-striated
stem, not unlike that of some reed.

The coal itself is of a more or less slaty-structure, and ap-
proaches, in some specimens, to the nature of brown coal; its
colour is of a brownish black: it is easily cleft, and the planes
of separation, which are without lustre, exhibit here and there
black shining spots, and lines apparently of a bituminous
nature. It emits no unpleasant smell when burning, and leaves
copious greyish-white ashes. This coal is not the same with
that of Disco Island, which contains the amber ; it differs from
it both in colour and structure. There is a piece of fine pitch
coal or jet among the objects picked up in the neighbourhood of
Cape Hearne.

Part of the specimens of argillaceous and brown ironstone,
found in Melville Island, evidently belong to the same formation
as the sandstone so abundant in these parts, and are alike con-
comitants of the coal. They consist chiefly of rounded pieces,
and likewise of geodes: the former appear also to exist here in
the shape of aconglomerate. Some specimens from Table-hill
and its neighbourhood, as also from Liddon’s Gulf, are marked
with the impressions of bivalves, particularly of a small, flat,

.

collected by Captain Parry. 21

ovate cuneiform species of mytilus. One of the fragments of
compact brown iron stone exhibits a glossy surface and fracture,
approaching to fibrous.

There are also specimens of sandstone which exhibit a tran-
sition into a kind of brown ironstone: in this state it is gene-
rally seen as tabular pieces, similar to that which in some parts
of Norway, §c., is deposited in beds of a few inches’ thickness
in sandstone, into which it passes.

_ In the same manner the hydrous oxyde of iron is seen to pe-
netrate clay which here and there slightly efferyesces with acids,
and is therefore a ferruginous marl.

There are a few varieties of slate-clay, such as might be ex-
pected to occur with coal and sandstone formations: they are
very soft, of ash-grey, and greenish-grey colour, and were found
overlaid by sandstone at the bottom of ravines.

The limestone from Melville Island, especially that from
Table-hill, bears the character belonging to that of the oldest
fletz or transition formation. The secondary fossils which it
contains are chiefly bivalve shells and corallines. None of these,
however, are perfect enough to admit of the determination of
the genera to which they respectively belong, except a small
species of Terebratula of that division which comprehends the
Petunculi of earlier writers on petrifactions, and a species of
Favosites, which does not appear to differ from F’. Gothlandicus.

There are a few specimens among those from Winter Harbour
and Table-hill, which appear to bespeak the presence of fletz
trap-rocks in Melville Island; but being found as rolled stones,
they do not allow any judgment being formed of the relation in
which they stand to the other formations. I haye seen from
those parts a few small fragments of calcedony, with opaque
stripes like the onyx from Iceland and Ferroe ; fragments of red
jasper, and of a jaspery breccia; a piece of a compact horn-
stone-like mass of greenish colour mixed with reddish, and
small rolled pieces of basalt. There is also among them a spe-
eimen of wood-hornstone of greyish-brown colour, with concen-
tric. yellowish-white rings. Nor should I omit mentioning a
similar specimen of wood stone from Byam Martin’s Island,

22 Mr. Macneill on the Influence of

with numerous close concentric rings, the curve of which indi-
cates its being a fragment of the stem of a petrified dicotyle-
donous tree. Itis susceptible of taking a beautiful polish.
I remain, my dear Sir, with great regard,
Very sincerely yours,
Cuares Konic.

Art. IV. On the Influence of Local Attraction upon the
Magnetic Needle, by Mr. Joun MAcneEILu.

{In a letter to the Editor.]

[{Mr. Macneill has obligingly forwarded us a map of the district alluded to
in the following communication, but as the subject is sufficiently intelli-
gible without it, we have not thought it necessary to delay the publica-
tion of the paper.]

Sir, Mount Pleasant, January 20th, 1823.

In the progress of a trigonometrical survey, in which I am
now engaged, of the County Louth in Ireland, I have frequently
observed instances of a local attraction, by which the magnetic
needle is considerably affected; the most remarkable instance
of this I observed in the beginning of this month, on the South
side of the range of mountains which runs from Newry to
Carlingford, and not more than two miles north of Dundalk;
this range is here broken into deep glens, bordered by conical
and detached hills. One of these, which appears especially
to cause a deviation in the needle, is not of so consider-
able an elevation as many of its neighbours, but rises coni-
cally on the side of the principal range: its surface is rocky
and uneven, with very little freestone towards the south and
south-west; I have sent you a small specimen of the stone of
which it appears to be composed, and which affects the mag-
netic needle very powerfully; the principal object I had in
view in observing the deviation of the needle in the different
parts of this county, was to exhibit on my map such districts
as could not be surveyed by the needle, for I am sorry to say,
that the old and imperfect instrument the circumferenter, still

Local Attraction upon the Magnetic Needle. 23

continues to be used by land surveyors, with very few excep-
tions throughout the whole of this country ; and as it must be
evident, that any survey made by the needle in such a district as
the one in question must be incorrect, I conceived it would not
be unacceptable to many to have such information inserted in
acounty map. From a mean of ten observations of the sun, I
found the variation of the needle from the true meridian to be
28° 9’ 41” at the point C towards the west; at the point 9, a
distance of 45 perches from the former, it was 29° 2’, and at
8, distant 38 perches from the last, it was 29° 40’; at the point,
7, a distance of 20 perches, it was 30° 4’; at the point 6, a dis-
tance of 15 perches, it was 31° 40’; at the point 5, a distance
of 28 perches, it was 32° 45’; at 4, it was 31° 37’, the distance
41 perches ; at 3, it was 30° 1’, the distance 20 perches; at 2, it
was 29° 7’, the distance 29 perches ; and at the point 1, it was
28° 10’; at which it has again become very nearly the true
annual variation of the year: the lines D, 1, 2, 3, &c., are the
magnetic meridian, and the red lines shew the deviation of the
needle at those points. I have taken the liberty of forwarding
you the above trifling remarks, which perhaps you may think
worthy of some notice in your valuable and useful publication.
I have the honour to be, Sir,
With respect, your obedient servant,
Joun Macnei.t. ~

Arr. V. Lamarcx’s Genera of Shells.
(Continued from Vol. XIV. p. 322.)
9th Family.
Natapa*, (4 Genera.)

Fresh water shells. -Hinge sometimes with an irregular,
simple, or divided cardinal tooth, and a longitudinal tooth ex-
tending under the corselet ; sometimes no tooth, or is furnished,
through its whole length with irregular, granular tubercles.

Muscular impression posterior, compound. Beaks decorticate,
often eroded.

* River Nymphs.

24 Lamarck’s Genera of Shells.

‘ The Naiada are well distinguished from the fresh” water
conche by their hinge, and the animal inhabitant. The shell
is free, regular, equivalve, inequilateral, always transverse; the
epidermis is greenish, inclining to brown, and is always wanting
at the beak. The muscular impressions are lateral, and quite
separate ; that of the posterior side is composed of two or three
distinct or unequal impressions, which distinguishes them from
the other bimuscular conchifera.

The animal has no projecting syphon or tube; its foot is
lamellar, transversely elongated, and rounded, which it pro-
trudes beyond the valves, and uses for locomotion. It generally
remains partly buried in the mud, with the beaks immersed.

1. Unio*.

Shell transverse, equivalve, inequilateral, free; beaks decor-
ticate, almost eroded. Muscular impression posterior, com-
pound. Hinge with two teeth on each valve; one, cardinal,
short, irregular, simple, or bifid, substriated; the other elon-
gated, compressed, lateral, channelled, extending under the
corselet, for a considerable space along the lower margin on that
side. Ligament external.

Linnzeus confounded the Unio with the Mya, although the
latter is a sea shell, and very different in form, hinge, position
of the ligament, and the animal which inhabits it.

The Unio is eminently distinguished from the Anodonta,
(which it resembles externally,) by its hinge. Each valve has
a short cardinal tooth, that on the left valve generally simple,
that on the right divided into two lobes, besides a lateral tooth,
as described above. The two teeth of each valve articulate toge-
ther when the valves are shut. The shell of the Unio is formed
in general, of a very brilliant mother-of-pearl ; externally, it is
covered with a greenish or brown epidermis, except on the
beaks, which are decorticate, and more or less carious. Lastly,
the lamina of the margin of the shell, above the lateral tooth,
has a truncation or sinus, which seems to receive a portion of

¢ A pearl called an Union, from unus, because no two, found in the same
shell, are alike.

Lamarck’s Genera of Shells. 25

the ligament. The Uniones live buried in the mud, in rivers,
with the beaks downwards, and many of them produce tolerably
fine pearls. Several are slightly gaping.

This genus is subdivided into(1) shells with the cardinal tooth
short, thick, not crested, (ex créte) and substriated, 30 species;
and. (2) cardinal tooth short, flattened, prominent, and often
crested,—18 species.

Type. Unio sinuata*. (Mya margaritifera? Linn.)

Shell ovate-oblong, compressed, sinuous, on the upper part
thick ; nates rather prominent; cardinal tooth thick, lobed,
striated. Rivers of the European Continent. In all 48 species.
Pl. I. Fig. 69.

2. Hyriat.

Shell equivalve, obliquely triangular, auriculated ; base trun-
cated and straight. Hinge with two low teeth; one, posterior
or cardinal, divided into numerous diverging parts, of which
the interior are the smallest; the other, anterior or latera.,
very long, and lamellar. Ligament external, linear. The
Hyria is distinguished from the Unio, by its general form, and by
the cardinal tooth, particularly that on the right valve, which is
divided into numerous lamellar folds, the innermost very small,
and has the appearance of a bundle of very unequal, diverging
lamine. This compound tooth is rather depressed than pro-
minent, and always inclines towards the posterior side of the
shell, instead of rising perpendicularly to the plane of the valve.

Type. Hyria avicularist. (Mya Syrmatophora? Ginel.)

Shell with umbones and nates smooth; ears large, produced
to a point, subacute. Brazil? 2 species. PI. I. Fig. 70.

3. Anodonta§.

Shell equivalve, inequilateral, transverse. Hinge linear,
without teeth. Base of the shell terminated by a smooth car-

* Sinuous.

+ Teor, a honeycomb—alluding, we suppose, to the form of the cardinal
tooth.

¢ Allied to the avicula.

§ Avdus, from a, not, and odus, a tooth, having no teeth.

26 Lamarck’s Genera of Shells.

dinal lamina, truncated or forming a sinus at its anterior exter-
mity. Two distant muscular impressions, lateral, subgeminal.
Ligameut linear, external, its anterior extremity inserted in the
sinus of the cardinal lamina.

The anodonte, which Linnzeus confounded with the Mytili,
are fresh water shells, usually very thin, and often of a large
size. They greatly resemble the Uniones, but have neither
cardinal nor lateral tooth, the hinge presenting merely a smooth
interior margin, or lamina, situated immediately below the
nymphe, and terminated anteriorly by a truncation or sinus.
The shell is nacreous, and covered externally with a thin,
greenish, false epidermis; beaks decorticate, oblique, partly
inclining to the posterior margin. The animal has two short
tubular apertures, formed by the posterior extremity of the
mantle, and furnished with little tentacular threads. It has
no byssus; it has a very large, almost round, compressed muscu-
lar foot, which it uses for locomotion. It is hermaphrodite, and
seems to be viviparous, for the ova pass between the branchie,
where the young are found with their shell perfectly formed.

The species are subdivided into(1) shells without any distinct
angle at the posterior extremity of the cardinal line, 10 species ;
and (2) those which are distinctly angular at that part, 5 species.

Type. Anodonta Cygneus*. (Mytilus cygneus, Lenn.)

Shell ovate, brittle, posteriorly dilated, rounded; with un-

equal transverse furrows ; nates obtuse. Lakes, §c of Europe.
In all 15 species. PI, I. Fig. 71.

4. Iridinat.

Shell equivalve, inequilateral, transverse; beaks small, slight-
ly curved, almost straight. Muscular impressions as in the
Anodonta. Hinge long, linear, attenuated towards the middle,
tubercular through its whole extent, almost crenate ; tubercles
unequal, frequent. Ligament external, marginal.

The principal difference between the Anodonta and Iridina,
consists in the tuberculated hinge of the latter, in other re-

* From eygnus, a swan. + From iris, a rainbow.

Lamarck’s Genera of Shells. 27

spects they are very similar. The shell is rather thick, brilliant
pearly, reddish, especially internally, and iridescent.

One species. Iridina exotica*.

Shell transversely oblong, longitudinally striated ; strice very
delicate ; lateral edges rounded ; beaks slightly projecting above
the hinge. Rivers of Hot Climates. Pl. 1. Fig. 72.

10th. Family. '
Cuamacea. (3 Genera.)

Shell inequivalve, irregular, fixed. Hinge with one thick
tooth, or none at all. Two separate, lateral, muscular impres-
sions.

The ligament of the shells belonging to this family is exter-
nal, and sometimes sunk irregularly towards the interior; with
respect to the hinge, they have some analogy to the tridacnea ;
they are often lamellar and spinous, their beaks always irregu-
lar, sometimes large and contorted. The animal has only
short, disunited syphons. ‘The shells are attached to rocks,
corals, and often to each other.

1. Diceras+.

Shell inequivalve, adhering; beaks conical, very large, di-
verging, irregularly spiral. One very large, thick, concave,
subauricular, prominent tooth, in the largest valve. Two mus-
cular impressions.

The diceras somewhat resembles the isocordia in external

* Exotic. We have given the characters of I. exotica, as being the only
species described or named by Lamarck. Mr. Sowerby (Genera of Recent
and Fossil Shells,) has a beautiful figure of another species, I. elongata ; and
Mr. Swainson, (Phil. Mag. 1xi.112,) has described three species, viz., J.
striata, I, elongata, and I. ovata. Our figure is taken from the single polished
valve, in the British Museum, which Mr. Swainson thinks probably belongs
to the last species, if properly to either of them. It was certainly a mis-
take, as he observes, to call it J. exotica. Mr. Swainson describes the
I. ovata, as follows. ‘Shell smooth, transversely oval ; umbones promi-
nent and nearly medial.”

+ From tic and xegac, signifying with two horns ?’

98 Lamarck’s Genera of Shells: .

form, but it is more nearly allied to the chama, in which genus
Bruguiere has included it. It differs from them, however, by
its hinge, and the singular form of the beaks.

Only one species. Diceras arietinum*. (Chama bicornis.
Brug.)

Fossil, from Mont Saléve. France, Pl. I. Fig. 73.

2. Chamat.

Shell irregular, inequivalve, fixed; beaks curved, unequal.
Hinge with only one thick, oblique, subcrenate tooth, fitting
into a pit on the opposite valve. Two distant, lateral, muscu-
lar impressions. Ligament external, depressed.

In the genus chama Linneus has included very dissimilar
shells, uniting regular and equivalve shells with those that are
irregular and inequivalve, and free shells with fixed. Bruguiere
reformed this genus, which now consists of irregular, coarse,
rough, scaly or ‘spinous shells, with very unequal valves, and
only one thick, oblique, transverse, callous tooth, usually crenate
or furrowed. The beaks are curved inwards, and only one of
them projects at the base of the shell.

The chamz usually live in shallow salt water; they are
always found attached to rocks, or corals, by the larger valve,
or adhering together in various groups: except the scaly or
lamellar species, they are seldom brilliantly coloured. This
genus is subdivided into (1) shells, whose beaks turn from left
to right, 10 species; and (2) those from right to left, 7 species.

Type. Chama lazarus. (Idem, Linn.)

Shell imbricate; lamelle dilated, wavy-plicate, sublobate,
obsoletely striated. American Ocean. In all, 17 recent spe-
cies, and 8 fossil. Pl. I. Fig. 74.

3. Etheriat .

Shell irregular, inequivalve, adhering; beaks short, sunk, as

* Of, or belonging to, a ram.

+ Chama, the Latin name of a species of shell fish, said to be derived
from yaww, to gape.

¢ One of the oceunides, or sea-nymphs.

Lamarck’s Genera of Shells. 29

it were, in the base of the valves. Hinge without teeth, wavy,
subsinuous, unequal. Two distant, lateral, oblong muscular
impressions. Ligament external, tortuous, partly penetrating
the shell.

The etheriz are very rare shells, and little known, being
attached to rocks at a considerable depth in the sea. They
might be mistaken for ostree, from their irregular form, but
they are allied to the chame by their separate, lateral, bi-
muscular impressions, and indeed are only distinguished from
them, by having no tooth at the hinge; they are, however, much
more pearly and brilliant than the chamz internally, and their
shell is perfectly foliated, like that of the ostree. Most of them
are rather large, and all are attached by the lower valve.

This genus is subdivided into (1) shells having an oblong
callus in the base of the shell, 2 species ; and (2) those which
have no such callus.

Type. Etheria semilunata*.

Shell obliquely ovate, semi-circular, rather gibbous ; posterior
side straight; nates conformable, nearly equal. Indian Ocean?
In all 4 species. PI. I. Fig. 75.

Second Order.

CoNCHIFERA UNIMUSCULOSAt.

Only one muscle, which appears to pass through the body.
Shell with one internal muscular impression, nearly in the centre.
The distinguishing characteristic of this order is the singular
muscle by which the animal is attached to its shell, the impres-
sion of which, is generally discernible in each valve, sometimes
very large and remarkable. The shell is generally irregular,
inequivalve, and of a foliated texture; but, besides that these
characters are not peculiar to the genera belonging to this order,
* Crescent-shaped, Lamarck’s first species of the second subdivision.
The shell, from which our figure is taken, was obligingly lent us by Mr.
Sowerby. It is extremely difficult to determine the species of some of the
irregular shells, whose forms are liable to almost infinite variations. We
think our specimen is pretty certainly E. semilunata, but possibly that, and
the other, non-callous shell, E. transversa, given hy Lamarck, may be

merely varieties in shape of the same species.

+ Having one muscle.

30 Lamarck’s Genera of Shells.

since the same is nearly the case with the chamacea, they are not
common to all of them; for some, as the pectines, &c., have a
regular shell, without a distinctly-foliated texture, others, as the
lingula, have their valves equal, or very nearly so.

This order consists of three sections, the first containing three
families, the second and third, two each.

Section Ist.

Ligament marginal, elongated on the edge, sublinear.
Most of the shells of this section adhere to marine substan-
ces by a byssus ; several of them are equivalve, not foliated.

Ist Family.
TRIDACNEA, (2 genera.)

Shell transverse, equivalve, muscular impression below the
middle of the superior margin, and extending, on each side,
under it.

The shells of this family are regular, solid, and remarkable
by their sinuous or wayy superior margins.

1. Tridacna *.

Shell regular, equivalve, inequilateral, transverse ; lunula
gaping. Hinge with two compressed, unequal, anterior, enter-
ing teeth. Ligament marginal, external.

Linneeus confounded the tridacne with the chame. They
are rather handsome shells, often above the middle size, and
sometimes so gigantic, that one species, (T. gigas,) is the largest
shell known.

The animal has but one transverse muscle, and the interior
of the shell exhibits a single, elongated, arched, muscular impres-
sion, running below the superior limb, and widest at the middle
of the margin of the valves.

The tridacna is perfectly distinguished from the hippopus, by
the lunula always being open and gaping, through which the
animal protrudes a byssus, to fix its shell to the rocks, and by

* From cezs, three, and daxve, to bite. A name given to a kind of oyster,
so large as to require to be eaten in three pieces.—Plin. 32. 6.

-

Lamarck’s Genera of Shells. 31

which it is suspended, however large and heavy itmay be. The

cardinal teeth are on the anterior side, below the corselet. In

most species, the margin of the lunular aperture is crenate.
Type. Tridacna gigas *. (Chama gigas? Linn.)

Shell very large, transversely ovate; ribs large, imbricate-
squamose ; squame short, arched, crowded ; interstices between
the ribs not striated. :

Indian Ocean, 7 Species. Pl. I. Fig. 76.

A shell of this species was given to Francis I. of France, by
the Republic of Venice, the valves of which are used to hold the
holy water, in the Church of Saint Sulpice, at Paris. Although
enormously large, there are others still larger. The biggest
known is said to weigh five hundred pounds.

2. Hippopus +. }

Shell equivalve, regular, inequilateral, transverse; lunula
close. Hinge with two compressed, unequal, anterior, entering
teeth. Ligament marginal, external.

The hippopus differs from the Tridacna, by having the lunula
shut; the margin of the valves at that part being indented, but
close together ; wherefore the animal cannot fix itself to rocks
by a byssus, like the tridacna, and consequently must have a
different organization from that of the preceding genus.

The general form and appearance of the two shells is very
similar.

One species. Hippopus maculatus t, (Chama hippopus. Linn.)

Shell transversely ovate, ventricose, ribbed, subsquamose,
white with purple spots ; lunula cordate, oblique.

Indian Ocean. Pl. I. Fig. 77..

2nd. Family.
Myvriiacea, (3 Genera.)

Cardinal ligament subinternal, marginal, linear, very entire,
occupying a large portion of the anterior margin, and, by its
elasticity, tending to keep the valves open. :

The shell of the mytilacea is elongated, equivalve, regular,

* Giant. + From immo; a horse, and ws¢ a foot. + Spotted.

32 Lamarck’s Genera of Shells.

seldom foliated with a slight, usually rather elongated mus-
cular impression on each valve. - The contraction of the muscle
of attachment enables the animal to close the shell completely,
(except those which have gaping valves,) but as that, if conti-
nual, might be injurious to it, it is provided with an interior,
and sometimes double adductor, ligament, first noticed by Dr.
Leach, which keeps the valves half open for the free passage of
the water, at once counteracting the tendency of the cardinal
ligament to open the shell entirely, and relieving the muscle from
a state of constant contraction. Most of these shell-fish are
fixed to marine bodies by a byssus, and have a tongue shaped,
or conical foot, which they use to draw out and attach the fila-
ments of the byssus.

1. Modiola*.

Shell-subtransverse, equivalve, regular ; posterior side very
short. Beaks almost lateral, depressed on the short side.
Hinge without teeth, lateral, linear. Ligament cardinal, almost
wholly internal, inserted in a marginal channel, beginning under
the beaks, and extending to part of the anterior, inferior mar-—
gin of the valves. One sublateral, muscular impression, elon-
gated, axe-shaped.

Almost all naturalists have hitherto confounded the modiole
with the mytili. They differ from them however, in being rather
transverse than longitudinal shells, the beaks not being truly
terminal, a slight projection of the posterior side extending
beyond them ; which projection Lamarck considers as the short
side of the shell. Moreover they are rarely fixed by a byssus,
although they are spinners, (jileuses,) like the mytili. Their
muscular impression is superficial, and analogous to that of the
mytili. They usually gape a little at the middle of the contracted
margin of the posterior side.

Type.. Modiola papuana +.

Shell oblong, solid, whitish violet; anterior side obliquely
dilated ; umbones tumid, obtusely angular.

North America. 23 recent Species, 5 fossil. Pl. I. Fig. 78.

* A little measure, or bucket: diminutive, from modius, a bushel. + Papuan.

Lamarck’s Genera of Shells. 33

2. Mytilus *.
’ Shell longitudinal, equivalve, regular, pointed at the base,
fixed by a byssus. Beaks almost straight, terminal, pointed.
Hinge lateral, usually without teeth. Ligament marginal, sub-
internal. One elongated, clavate, sublateral muscular ime
pression.

Linnzeus confounded the ostrez, aviculz, anodonte, &c., with
mytili, though the two first, are inequivalve and foliated, and
the last, fresh-water shells.

The mytili are all sea shells, not foliated, nor gaping at the
superior margin, in which they differ from the pinna, which
in other respects they a good deal resemble. Their byssus is
short, with thick or coarse filaments, which they attach and de-
tach by means of a linguiform foot. They have a rather slender
adductor ligament in the upper internal part of the shell, an-
swering the same purpose as that of the modiola; and another
ligament, pretty much like the former, in the base of the shell,
near the beaks, to strengthen the connexion of the valves at the
hinge.

The species are subdivided into, (1) Shells longitudinally
furrowed,—11 species,—and (2) Those having no longitudinal
furrows, 24 Species.

Type. Mytilus Magellanicus +.

Shell oblong, angular and whitish below; purplish violet
above, with thick, wavy longitudinal furrows; nates acute,
nearly straight. Streights of Magellan. In all 35 recent spe-
cies, and 2 fossil. Pl. I . Fig 79.

- 3. Pinna +.

Shell longitudinal, cuneiform, equivalve, gaping at the sum-
mit, base pointed, beaks straight. Hinge lateral, without teeth.
Ligament marginal, linear, very long, almost internal.

The pinne are sea shells, generaily very large, thin in pro-
portion to their size, often brittle ; upper margin rounded some-

* Original Latin name for the muscle shell fish.
+ From the Straits of Magellan.
+ Twa, pinna, a kind of shell fish, also a plume, whence the name.

Vou. XV. D

34 Lamarck’s Genera of Shells.

times almost truncated. Ligament narrow, and so compact,
that the valves seem to be joined together on the hinge side,
and admit of little motion for opening them. Texture of the
shell, though thin and sometimes foliated, solid; its fracture
exhibits delicate transverse strize, similar to those of gypsum.

The pinne are distinguished from the mytili, by the straight-
ness of the beaks, and the gaping of the superior extremity.

The animal is long, without any projecting siphon, and has
a conical linguiform foot, which it uses in fixing its fine, long,
shining, and silky byssus.

Type. Pinna rudis * ({dem, Linn.)

Shell large, oblong, ferruginous red ; apex obliquely rounded ;
furrows thick, squamiferous ; squamz large, semi-tubular.

Atlantic Ocean. 16 Species. Pl. I. Fig. 80.

3rd Family.
Matteacea. (5 Genera.)

Ligament marginal, sublinear, either interrupted by indenta-
tions, or serial teeth, or quite simple. Shell sub-inequivalve,
foliated.

Although allied to the mytilacea by similarity of position of
the ligament, the mallacea differ from them by the foliated tex-
ture of the shell, and by its being irregular and inequivalve.
Their ligament also is not perfectly internal, for, extending along
the lower margin of the valves, the facets which receive it in-
celine outwards, forming an open channel, and discovering more
or less of the ligament.

1. Crenatula-t.

Shell subequivalve, flattened, foliated, rather irregular. No
particular aperture or pit for the byssus. Hinge lateral, mar-
ginal, linear, indented ; indentations serial, callous, hollowed
into pits, and receiving the ligament.

The hinge of the crenatula a good deal resembles that of the
perna, but it is singular, by presenting a row of callous and rather
concave indentations, which receive the ligament, whereas that

* Rude. + A little nofch,—dim. from crena, the notch of an arrow, &e.

Lamarck’s Genera of Shells. 35

of the perna has a row of linear, parallel, truncated teeth, ar-
ticulating with those of the opposite valve, the ligament being
inserted in the interstices of the corresponding teeth.

The crenatule are rare shells, generally thin, sometimes
almost membranous, and brittle.

Type. Cranatula modiolaris *.
Shellsub-cuneiform, compressed, sub-membranaceous, reddish,
radiated with white ; nates below the base, separated by a sinus.
South American Seas. 7 Species. PI. 1. Fig. 81.

2. Perna ft.

Shell subequivalve, flattened, rather deformed; texture la-
mellar. Hinge linear, marginal, composed of sulciform, trans-
verse, parallel non-entering teeth, between which the ligament
is inserted. A posterior sinus, slightly gaping, below the ex-
tremity of the hinge, for the passage of the byssus; sides
callous.

The hinge of the perna is so peculiar, that it is surprising
Linnzus ‘should have classed it with the ostreee; it does not
even belong to the family of ostracea. It differs from the arca,
by the cardinal teeth of one valve not articulating with those of
the opposite valve, but, when the shell is shut, lying upon them.
The ligament also is differently situated from that of the arca.
They have much more resemblance to the crenatule ; they are
sea shells, with small, nearly equal beaks, situated at one of the
extremities of the hinge. The shell, though pretty solid, is
composed of ill-joined laminz, as is the case, with the other
malleacea.

Type. Perna ephippium =. (Ostrea ephippium. Lznz.)
Shell compressed, on the upper part orbicular; posterior side
longest; margin very acute. Indian Ocean. 10 recent species,
and 2 fossil. Pl. I. Fig. 82.

* Allied to modiola. Wamarck’s second species. His type is C. avicularis,

+ Perna, strictly, isa gammon of bacon, with the leg on. It was used to
denote a kind of shell fish, (very probably our perna,) from its resemblance
toapig’s foot. (Plin. 32. sub. fine.)

t From em, upon, and immo;, a horse—a saddle,

iy-2

36 Lamarck’s Genera of Shells.

3. Malleus*.

Shell subequivalve, rude, deformed, generally elongated, sub-
lobate at the base; beaks small, diverging. Hinge without
teeth. An elongated, conical pit, below the beaks, obliquely
traversing the facet of the ligament. Ligament subexternal,
short, inserted in the short, sloping facet of each valve.

The mallei are distinguished from the perne by their hinge;
from the avicule by the conical pit below the beaks, and by
the valves being, though irregular, of the same size, and having
no sinus on the left valve. The mallei are remarkable for their
form; they are coarse, irregular shells, with little beauty exter-
nally. Internally they are rather brilliant pearly, especially at
the part occupied by the body of the animal. They are exotic
sea shells, and some of the species (as the malleus albus) very
rare. They have a byssus, which protrudes through a small
posterior aperture, near the beaks. The inclined sides of the
valyes form an open channel at the base.

Type, Malleus albus T.
Shell trilobate; lateral lobes of the base very long; no sinus
for the byssus, or not distinct from the pit of the ligament.
South-oriental seas. 6 Species. PI. I. Fig. 83.

4, Avicula f.

Shell inequivalve, brittle, rather smooth; base transverse,
straight ; extremities produced, the exterior caudate. A sinus
in the left valve for the passage of the byssus. Hinge linear,
unidentate ; cardinal tooth of each valve under the beaks.
Facet of the ligament, marginal, narrow, channelled, not tra-
versed by the byssus.

When the valves are spread open, without separating, the
shell has a rude resemblance to a bird on the wing, whence its
name. —

The aviculz are sea shells, generally muticate, or not squa-
mose externally, thin, and pearly within. Their beaks are ob-
lique, small, and not prominent.

* A hammer. +t White. i A little bird.

Lamarck’s Genera of Shells. 37

Type. Avzcula crocea*.
Shell smooth, muddy yellow, not spotted; wing obliquely
divaricate.
Isle of France. 15Species. PI. I. Fig. 84.

5. Meleagrina +.

Shell equivalve, quadrato-rotundate, externally squamose ;
lower cardinal margin straight, anteriorly not caudate. A sinus
at the posterior base of the valves, for the passage of the byssus ;
margin of the left valve at that part narrow, emarginate. Hinge
linear, without teeth. Facet of the ligament marginal, elon-
gated, subexternal, dilated in the middle.

The meleagrina is distinguished from the avicula, by the dif-
ferent form of its shell, which is nearly equivalve, by its never
having the tail nor cardinal teeth of that genus, and by the widen-
ing of the ligamental facet at the middle part. The aperture
for the byssus also occasions a callous, re-entering angle on
each valve, which is not found on the avicule. The meleagrina
is not so smooth, and more squamose than those shells; its in-
ternal pearly coat is sometimes thick, and very brilliant, and it
often contains true pearls. The finest of those “ costly and
beautiful substances {,” are found in one species, (M. margan-
tifera,) of this genus.

Type. Meleagrina margaritifera§. (Mytilus margaritiferus,
Linn.)

Shell subquadrate, rounded above, greenish brown, with
white rays; lamelle longitudinal, imbricate ; the upper ones
largest.

Persian Gulf. 2 Species. PI. II. Fig. 85.

Section 2nd.

Ligament not marginal, contracted into a short space below
the beaks, always visible, and not forming a tendinous cord
under the shell.

The shells of this section are well distinguished from those
of the preceding by the form and situation of the ligament.

+ Saffron colour—yellow. Lamarck’s sixth species. + Medcaygs, a Guinea

fowl.
t Davy. § Pearl-bearing.

38 Lamarck’s Genera of Shells.

They are generally auriculated at the base or extremity of the
cardinal margin. They are all inequivalve, for, though in many
the valves are of the same size, one of them is always more
convex than the other.

Ist. Family.

Pecrinipa. (7 Genera.)

Ligament internal, or semi-internal. Shell generally regular,
compact, not foliated.

The pectinida are usually auriculated, and striated ; the
strie, or ribs, radiating from the beaks. The ligament is internal,
but sometimes visible on the outside, in consequence of an in-
dentation between the beaks, or of their distance from one
another. Some are free shells, which the animal attaches at
pleasure by a byssus ; others are fixed to marine substances by
the lower valve.

1, Pedum *.

Shell inequivalve, slightly auriculated, lower valve gaping.
Beaks unequal, distant. Hinge without teeth ; ligament partly
external, inserted in an elongated, channel-shaped pit, formed
in the lower side of the beaks; lower valve notched near the
posterior base.

The pedum is a free, regular, inequivalve shell ; and the sin-
gular notch of the lower valve shews that the animal has the
power of attaching it by a byssus. One Species.

Type. Pedum spondyloideum +, (Ostrea spondyloidea, Gmel.)

Shell cuneiform oval, rather flat; upper valve longitudinally
striated ; striz rough, granular.

Indian Seas. PI. Il. Fig. 86.

2. Limat.

Shell longitudinal, subequivalve, auriculated, slightly gaping
at one side between the valves; beaks distant, their internal
facet inclining outwards. Hinge without teeth. Cardinal pit
partly external, receiving the ligament.

The lima has no notch on the lower valve; the little ears at
the base of the shell, though small, are distinct. Linnzus ar-

* A shepherd’s crook. 1 Resembling a spondylus. + A file.

Lamarek’s Genera of Shells. 39

anged these shells with the ostrew, but they differ from them
in being free, regular and almost equivalve, and from the pec-
tines by their remote beaks, and cardinalpit. They are sea-
shells, and generally white.
Type. Lima squamosa*. (Ostvea Lima. Linn.)
Shell oval, depressed, cut off as it Were at the fore part ; ribs
squamose, very rough ; hinge oblique; margin plicate.
American Ocean. 6 recent species, and 5 fossil. Pl. I. Fig. 87.

3. Plagiostoma f.

Shell subequivalve, free, subauriculated ; cardinal base
transverse, straight. Beaks rather remote, their inner sides ex-
tending into transverse, flattened, external facets, one straight,
the other obliquely inclined. Hinge without teeth. A conical
cardinal pit, situated below the beaks, partly external, opening
outwards and receiving the ligament.

The plagiostoma differs from the pecten, by the beaks not
being contiguous, by the external and flattened facets of the car-
dinal base, and by the pit for the ligament opening, by a hole,
outwards. Except that it wants their two cardinal teeth, the
hinge of the plagiostoma Yesembles that of the spondylus. It
is distinguished from the lima by not gaping at either side,
whence it cannot be attached by a byssus; for it is a mistake to
suppose that the external aperture of the ligamental pit serves
for the passage of that apparatus, a circumstance which never
occurs with the conchifera, and is incompatible with the dispo-
sition of the organs of the animal. The plagiostoma is’ only
known in the fossil state; its shell is generally thin, even in
those of large size. This genus was first observed by Mr.
Sowerby.

Type. Plagtostoma transversa {.

Shell very large, transversely ovate, rounded above ; lower
sides oblique ; longitudinal furrows very numerous, transversely
striated. 6 Species. PI. U. Fig. 88.

+ Squamose. Lamarck’s second Species. His type is L. influta.

+ From 1Waayiug, obliqnd, and evox, @ thonth. t Transverse.

40 Lamarck’s Genera of Shells.

4. Pecten*.

Shell free, regular inequivalve, auriculated ; inferior margin
transverse, straight; beaks contiguous, with no intermediate
facet. Hinge without teeth: a triangular cardinal pit, wholly
internal, receiving the ligament.

The pectines are almost always longitudinally radiated with
fine or coarse ribs ; the base of the shell is terminated by a
straight, transverse line, beyond which the beaks never project.
The valves are generally thin, of equal size, but not equally
convex, the upper being almost constantly flattened ; their tex-
ture is not loose-foliated like that of the ostresze. They are sea-
shells, much diversified, very numerous in species, and the spe-
cies not easily determined; they are usually ornamented with
various and brilliant colours. They are always auriculated, and
the largest ear is on the posterior side, and beneath it is a sinus.

The species are subdivided into (1) Shells with the ears
equal, or nearly equal,—26 species; and (2) Those with the
ears unequal,—32 species.

Type. Pecten maximus t. (Ostrea maxima. Linn.)
Shell inequivalve, upper valve almost flat; radii rounded,
longitudinally striated. Huropean Seas. In all 59 recent spe-
cies, and 26 fossil. Pl. II. Fig. 89.

5. Plicatula ¢.

Shell. inequivalve, not auriculated, contracted towards the
base ; upper margin rounded, subplicate ; beaks unequal, with
no external facet. Two strong cardinal teeth on each valve,
with an intermediate pit which receives the ligament ; ligament
wholly internal.

The plicatule are sea-shells; they differ from the pectines by
having cardinal teeth, and being without ears; and from the spon-
dyli, by having no external facet, nor consequently the inter-
mediate furrow, occasioned by the ligament of the spondyli;
nor are they spinous, like those shells,

* Acomb. Also the original} Latin name for, all shell-fish, striated, or
ribbed like cockles.*

+ The largest t Dim. from placa, a fold, or wrinkle.

Lamarck’s Genera of Shells. 4]

Type. Plicatula cristata *.
Shell oblong, cuneiform, ferruginous, subcristate ; folds large,
simple, squamose.
American Seas. 11 Species. Pl. II. Fig. 90.

6. Spondylus +.

Shell inequivalve, adhering, auriculated, spinous or rough;
beaks unequal; an external, flattened, cardinal facet on the
lower valve, divided by a furrow. Two strong cardinal teeth
on each valve, with an intermediate pit for the ligament, com-
municating at its base with the external furrow. Ligament in-
ternal; remains of former ligaments perceptible externally in
the furrow.

The spondyli are particularly distinguished from the ostrez
by the cardinal teeth; they are generally covered with spines,
which are occasionally very large, subulate, or lingular; some-
times simple, sometimes foliated at their summit, and always dis-
posed in rows, or longitudinal, radiating strie, or ribs. They are
for the most part variously and brilliantly coloured; the lower valve
is always the largest and most convex, and is terminated at the
beak, by a kind of talus, which appears as if cut with a sharp
instrument, and presents a flattened, inclined, triangular facet,
divided by a furrow. This cardinal area increases in length
by age, in consequence of the animal changing its place in the
shell as it grows, and at the same time displacing the upper
valve t.

The animal, like that of the pecten, has two rows of short,
tentacular threads on the border of the mantle, and the vestige

. * Crested. Lamarck’s third species. His typeis P. ramosa.

+ Emovduros, spondylus, a knuckle, or vertebra. Also the original Latin name
for a kind of shell-fish.

+ On this supposed dislocation of the upper valve, Mr. Sowerby very
pertinently remarks, ‘‘ The teeth of the two valves are so formed, that with-
out breaking away some portions of them, or of the circumjacent parts
of the hinge, the two valves cannot be separated. We have mentioned this
fact before in our account of the genus ostrea; and we here repeat it, to
shew how impossible it is that the animal should displace its upper valve,
as Lamarck asserts, in order to produce the progressive elongation of the

area of the hinge of the lower valve.” (Genera of Recent and Fossil
Shells. No. 9.)

42 Lamarck’s Genera of Shells.

of a foot, in the form of a radiated disc, and furnished with a
short pedicle.
Type. Spondylus gederopus. (Idem. Linn.)

Shell red above; striz small, longitudinal, close together,
rough, granular; from six to eight rows of sublingulate, trun-
cated, middle-sized spines.

Mediterranean. 21 recent species, 4 fossil. Pl. 2. Fig. 91.

7. Podopsis.

Shell inequivalve, subregular, adhering by the lower beak,
inauriculate ; lower valve largest, most convex, and its beak
most prominent. Hinge without teeth. Ligament internal.

The podopsides, which are only known in the fossil state, are
similar in some respects to the gryphcea, but are distinguished
from them, by the lower beak not being curved either above the
upper valve, or over the side. They resemble the pectines by
their regularity, by the shell not being foliated, and by their lon-
gitudinal strie. They appear to have some relation to the pla-
giostoma, but differ from them in being fixed shells, and in want-
ing the opposite beaks, with their intermediate, obliquely in-
clined facet. The upper valve of the podopsis, which is always
shorter than the other, seems to have no beak, in consequence
of its not being curved or prominent.

Type. Podopsis truncata *.

Shell longitudinal, cuneiform, rounded above, suboblique ;
strize longitudinal, thin, sometimes rough, with a few prickles ;
longest beak crenate.

Touraine. PI. IL. Fig. 92.

2nd Family.
Ostracea. (5 Genera.)

Ligament internal, or semi-internal, Shell irregular, texture
foliated, sometimes papyraceous.

Almost all the ostracea are irregular shells, of a foliated or
Jamellar texture, seldom auriculated at the base, and still more
rarely radiated externally.

The animal has no foot, arm, or projecting siphon; in many

* Truncated.

-

Lamarck’s Genera of Shells. 43

species, the shell is fixed to marine bodies by the lower valve,
which is always the largest. The first three genera of this
family have a semi-internal ligament, a foliated, and often very
thick shell. The two last have the ligament internal, and the
shell thin or papyraceous.

| 1. Grypheea *,

Shell free, inequivalve; lower valve large, concave; beak
prominent, curved spirally inwards; upper valve small, flat,
opercular. Hinge without teeth; cardinal pit oblong, arched.
A single muscular impression on each valve.

Animal unknown.

The generally large curved beak of the lower valve of the
gryphea, usually projects considerably, either above the upper
valve, or laterally, which eminently distinguishes these shells
from the ostrez ; they are, besides, almost always free shells, or
if they adhere at all to other bodies, it is only by a point ; most
of them appear tobe regular shells. The lower valve is always

much larger than the upper. They are all, but one species,
fossil, and are probably sea-shells.

Type. Gryphea angulata t.

Shell oblong ovate ; three longitudinal ribs underneath, angu-
lar-carinate; beak large, suboblique. Recent. Locality not
given.

11 Fossil species. PI. II. Fig. 93 +,

2. Ostrea §.

Shell adhering, inequivalve, irregular, beaks distant, becoming
very unequal by age; upper valve smallest, generally flat, and
gradually advancing forward, during the life of the animal. (See
note *,p. 41.) Hinge without teeth. Ligament semi-inter-
nal, inserted in the cardinal pit of the valves; pit of the lower
valve increasing by age, sometimes to a great length.

Linnzeus, looking only to their mutually being without teeth,

* From yeurec, one that has a hooked nose. + Angular.

t We have given a second figure of this genus, viz., G. Cymbium, (fossil,

fig. 93*,) the G. angulata, being“very rare and less characteristic of the spe-
cies usually found in the blue lias, &c.
\| Oyster,

44 Lamarck’s Genera of Shells.

associated the beautiful genus of the pectines, with that of the
ostreze, notwithstanding the former are free, regular shells, and
have the ligamental pit wholly internal. He, moreover, referred
some true ostrez to his mytili, viz., mytilus crista galli, mytilus
hyotis, and mytilus frons ; and added the whole genus perna, to
the ostree, although their hinge is so peculiar by its charac-
teristic indented line. Bruguiere first established the principal
limits of this genus, and Lamarck has since further reduced
them, by separating the vulsella, podopsis, and gryphea.

The shell of the ostrea is rude, rugged, often squamose, some-
times singularly plicated at the margins, and frequently very
thick. It does not curve upwards, like that of the gryphea.
The texture of the valves is loose-foliated ; the lower one, which
is the largest, and by which it adheres to marine bodies, is more
convex than the upper. j

The species are subdivided into (1) shells, with simple, or
wavy margins, but not plicate—32 species; and (2) those with
distinctly plicated margins—16 species.

Type. Ostrea edulis *. (Idem. Lenn.)

Shell ovate-rounded, base sub-attenuated ; membranes imbri-
cate, wavy; upper valve flat. European seas. In all 48 recent
species, and 33 fossil. PI. If. Fig. 94.

8. Vulsella ft.

Shell longitudinal, subequivalve, irregular, free; beaks equal.
Hinge with a prominent callus on each valve, depressed above,
with the impression of a conical, obliquely arched pit, for the
ligament.

The vulselle, though nearly allied to the ostrez, are distin-
euished from them, by having the valves always of nearly equal
size; the beaks equal, though somewhat separate; an equal,
projecting callus in the interior of each valve, under the beaks ;
and by the shell never being fixed by its lower valve. They are
often found in sponges; are pearly internally, and some species
gape a little at the posterior side.

Type. Vulselia spongiarum t.

, * Eatable. + Or volsella—tweezers.
+ + Of spunges. Lamarck’s 4th species. His type is V. lingulata.

Lamarck’s Genera of Shells. 45

Shell oblong, straight; base attenuated ; internally purplish
white ; transverse concentric wrinkles; longitudinally obsolete.
Indian Ocean. 7 Species. PI. Il. Fig. 95.

4. Placuna *.

Shell free, irregular, flattened, subequivalve. Hinge internal,
with, on the upper valve, two sharp longitudinal ribs, close at the
base, and diverging in the form of the letter V; on the other,
two ligamental impressions, corresponding to the cardinal ribs.

The two oblong, prominent, rib-like lamine, in the form of a
V, situated at the internal hinge, on the upper valve of the sheil,
is the essential character of this genus; they serve for the at-
tachment of the ligament, inserted in the two impressions of the
same form observable in the opposite valve. The valves of the
placune are thin, transparent, and of the same size. These
shells are large, orbicular, or subtriangular, sometimes trian-
gular, with only one internal! muscular impression, like the
ostree. Their texture is foliated.

Type. Placuna sella t. (Anomia sella. Linn.)
Shell subquadrangular, curved, broad, irregularly sinuous,
lamellar, wavy; bronze-coloured ; striz longitudinal, very fine.
Indian Ocean. 4 Species. PI. II. Fig. 96.

5. Anomia ¢.

Shell inequivalve, irregular, operculated, adhering by the
operculum; smaller valve perforated, usually flat, having a hole
or notch at the beak; the other valve rather larger, concave,
entire. Operculum small, elliptical, osseous, connected with
the internal muscle of the animal, and fixed to marine bodies.

The operculum of the anomia has been absurdly mistaken for
a third valve, being, in reality, only the dilated and thickened
extremity of the tendon of the interior muscle of the animal,
which forms a small, solid, elliptical, and almost bony mass, of
such a shape as to fill the hole or notch of the beak of the

* From 72£, a broad table ? + A saddle.
$ Avia, from 4, not, and yox.o¢ law,—non-conformity to the usual order,
anomalous.

46 | Lamarck’s Genera of Shelis.

flat valve, when the muscle is contracted. The perforated flat
valve is usually considered as the lower one in this genus, as
being that which rests on the bodies to which the shell is at-
tached; whilst with the ostres, the larger and most concave is
correctly styled the lower valve. The contrary is the case with
the terebratule, because it is the largest and most concave
valye of that shell which is-perforated at the beak. Indepen-
dently of the muscular attachment of the animal to the oper-
culum, the two valves are connected by an internal, cardinal
ligament, the impression of which is very perceptible.

The organization of the animal, according to Poli, is similar
to that of the oyster.

Type. Anomia ephippium*. (Idem, Linz.)

Shell suborbicular, rugose-plicate, wavy, rather flat; foramen
oval. .

Mediterranean. La Mancha, &c. 9 Species. Pl. II. Fig. 97.

. Section 3rd.

Ligament either none, or unknown; or represented by a ten-
dinous cord which supports the shell.

The shells of the two preceding sections have true, known
ligaments; those of the one we are now entering on have in
reality no true ligament, for the tendinous cord observed in
some of them, is merely the extremity of the muscle of attach-
ment of the animal, which passes through a hole, in the large
beak of the shell, and fixes itself to foreign substances, but by
no means serves to support the valves. This section contains
two families.

Ist. Family.

Rupista. (6 Genera.)

Ligament, hinge , and animal unknown. Shell very inequi-
valve. No distinct beaks.

The two remaining families, the last of the conchifera, pre-
sent us with very singular shell-fish, sometimes in consequence
of the form of the shell, and sometimes from the peculiarities of
the animal, of which we find no. example in the other conchifera,

* Saddle.

Lamarck’s Genera of Shelis. 47

The rudista are allied to the ostracea in certain respects, but
are eminently distinguished from them, by having neither hinge,
valvular ligament, nor muscle of attachment, nor any indication
of the places where these objects should be found. As they
are all fossil-shells, we can form no idea of the characters of
the animal that once inhabited them.

1. Spheerulites *.

Shell inequivalve, orbiculo-globular, somewhat depressed
above, externally echinate with large, subangular, horizontal
scales. Upper valve smallest, rather flat, opercular: its in-
ternal surface furnished with two unequal, subconical, curved,
and projecting tuberosities ; lower valve larger, rather ventricose,
with radiating scales, extending beyond the margin; cavity ob-
liquely conical, forming on one side, by the folding of the inter-
nal margin, a crest, or projecting keel. Interior of the cavity
transversely striated. Hinge unknown.

The spheerulites differ from the radiolites by having large
subangular scales on their exterior surface, which gives them a
foliated appearance, and by some dissimilarity in point of form,
their upper vaive being rather flattened, instead of conical ; and
it seems doubtful, if the interior surface of the smaller valve of
the radiolites have the two tuberosities of the spherulites; or
if the crest, or projecting keel, formed by the folding of the in-
ternal margin, on one side of the cavity, can be found in its
greater valve. .

One Species. Spherulites foliacea t.
No further description. Jsle of Atv. PI. II. Fig. 98.

2. Radiolites ¢. ’

Shell inequivalve, externally striated; striee longitudinal, ra-
diating. Lower valve turbinated, largest; upper valve convex,
or conical, opercular. Hinge unknown.

The radiolites appear to be formed of two, often very unequal
cones, applied base to base, and externally striated, but are not
squamose. These fossils are only found in the older formations;
they are tolerably abundant in the Pyrenees.

* From spherula, a litile globe. t Foliaceous. t From radius, a ray.

48 Lamarck’s Genera of Shells.

Type. Radiolites rotulans *.

Valves of the shell conical, applied base to base, rather

short, subequal. Pyrenees. PI. II. Fig. 99.
3. Calceola fF.

Shell inequivalve, triangular, turbinated, flattened below.
Largest valve hood-shaped, obliquely truncated at the aperture ;
cardinal margin straight, transverse, slightly notched, and in-
dented in the middle ; superior margin arched. Smaller valve
flattened, semi-orbicular, opercular, with a tubercle on each
side of the cardinal margin, and in the middle a pit with a
small lamina.

The calceola is a thick, solid shell, and in form not unlike a
half-sandal. Its cavity is striated from the centre to the cir-
cumference. The upper (flat) valve is marked externally with
concentric strite ; its cardinal margin seems to articulate with
the turbinated valve by a straight, linear, transyerse hinge. In
some individuals, the upper valve is slightly convex. Its lateral
tubercles have three grooves.

One species. Calceola sandalina. t. (Anomia sandalium, Linn.)

No further description. Environs of Juliers. Pl. II. Fig. 100.

4. Birostrites §.

Shell inequivalve, bicornute ; valves, in consequence of the
elevation of the disc, conical, unequal, obliquely diverging,
nearly straight, hornshaped ; the base of one valve enveloping
that of the other.

The birostrites is composed of two pieces, or valves, not
united by the margins of their bases, but one valve enveloping the
other, and the dorsal disc of each elevated into an almost °
straight cone, slightly arched within. These hornshaped valves,
are unequal, and diverge obliquely in the form of avery open V.
One valve appears to spring from the base of the other, the
shorter being always the enveloped valve. The interior of the
shell is unknown.

One species. Burostrites inequiloba ||.

* From rotula, a little wheel. t Calceolus, a little shoe,
+ From sandalum, a sandal. n
§ From bis, twice, or double, and rostrum, a beak, || Unequally lobed.

Lamarck’s Genera of Shells. 49

Shell with two conical, elongated, beak-shaped, unequal valves,
disposed at a very open angle, and united at their base ; mar-
gin of one valve enveloping that of the other valve.

Locality unknown. PI.II. Fig. 101.

Lamarck observes, in addition to what we have already
quoted, that the genus Birostrites is certainly very different from
his Diceras. Mr. Sowerby having had the opportunity of ex-
amining a cast of the inside of a birostrites, is convinced “ that
it ought to be placed next to diceras, or at least in the same
family with chama and diceras, (inasmuch as it accords very
nearly with those shells in its internal characters,) and that it
should not be placed in his (Lamarck’s) family of rudistes.”
Mr. Sowerby is further of opinion, that “‘ the whole family of
rudistes might be struck out ;” for two of the six genera which
it contains, spherulites and radiolites, he thinks are not shells ;
that calceola probably belongs to the next family, brachiopoda ;
that discina should be expunged, as being identical with orbicula;
and that “ cranza is decidedly a brachiopode.” We very much
incline to Mr. Sowerby’s opinion ; but as our professed object is
to give the Genera of Lamarck, we do not feel ourselves at
liberty to make the alteration he suggests to its full extent: he
has, however, so satisfactorily proved the identity of discina and
orbicula, that we do not hesitate so far to act on it, as to omit the
former altogether. For Mr. Sowerby’s arguments we refer our
readers to his paper, in the 13th vol. of the Transactions of the
Linnean Society.

5. Crania*.

e Shell inequivalve, suborbicular ; lower valve almost flat, per-
forated at the interior surface by three unequal oblique holes ;
upper valve very convex, having two internal prominent calli.
Animal unknown.

The crania generally adheres by its lower valve, the three
holes in which do not seem to perforate it completely, unless
by accident, when removed from the body to which it was fixed
by the outer surface; hence they cannot be the issues of mus-
cular attachments,

* Cranium, a skull,

Vor. XV. E

50 Lamarck’s Genera of Shells.

These holes give the lower valve the appearance of a death’s
head*, }
Type. Crania personatat. (Anomia craniolaris, Linn.)

Shell orbicular; the more gibbous valve conico-convex; the
flatter, with three little pitsat the base.‘

Indian Seas. The only recent species ewtnacthes other four
species are fossil. PI. II. Fig. 102.

2d Family.
Bracuiopopa f, (3 genera.)

Conchifera with two opposite, elongated, fringed arms, near
the mouth, which are rolled up in a spiral form, and enclosed in
the shell, when in a state of rest. These are peculiar to the
brachiopoda. Mantle with two lobes, separated in front, en-
veloping or covering the body.

Shell bivalve, adhering to marine bodies, either directly, or
by a tendinous cord.

The shell of the brachiopoda is more or less inequivalve, and
opens by ahinge. The true ligament of the valves is not known;
the tendinous cord is merely a prolongation of the muscular
attachment of the animal, and does not assist in opening the
valves. The shell always adheres to marine bodies. This: is
the last family of the conchifera.

1. Orbicula§.

Shell suborbicular, inequivalve ; no apparent hinge. Lower
valve very thin, nearly flat, adhering to marine substances ;
upper valve subconical ; summit more or less elevated.

The lower valve of the orbicula is sometimes so thin as to be

* Mr. Sowerby finds that these holes are muscular impressions, and that
they are four in number, instead of three, though two of them are so near
together, that he is not surprised that Lamarck, on a slight examination,
«¢ should have described the genus Crania as having, in the lower valve,
three oblique perforations.” He suggests the following as an amended
generic character ofthis shell. ‘ Crania.—Bivalve, inequivalve, nearly
orbicular, compressed, fixed ; upper valve patelliform, with four internal
muscular impressions ; lower valve adhering, nearly flat, with four corré-
sponding muscular impressions, two near the centre, approximating and
nearly united, and two near the posterior margin, distant. No hinge.—
Trans. Linn., Soc. xiii. Mr. Sowerby discovered the two fringed arms, pe-
culiar to the brachiopeda, in a Crania from Shetland. It should therefore,
as he observes, evidently be transferred to that family.

+ Masked. { From fpaxiwy, an arm, and wovs, a foot.

§ Orbiculus, a little round ball.

~

Lamarck’s Genera of Shells. 5i

scarcely perceptible, whence Maller supposed it to be an uni-

valye shell, and referred it to the patelle.

One Species. Orbicula Norvegica*. (Patella anomala. Mull.)

Upper valve compressed, conical ; summit pointed, inclining on

one side towards the margin. North Sea. PI. I. Fig. 103.
2. Terebratula ft.

Shell inequivalve, regular, subtriangular, attached to marine
substances by a short tendinous pedicle. Beak of the larger
valve prominent, often curved, perforated at the summit by a
round hole, or a notch. Hinge with two teeth; two almost
osseous, slender, elevated, forked, and variously ramified
branches, spring from the interior disk of the smaller valve, and
serve as a support for the animal.

The terebratulee appear to be sea-shells, of which some recent
species are known, but the greater number are fossil. The hole
in the beak of the largest valve serves for the insertion of the
fleshy tendinous pedicle, by which the shell is fixed to marine
substances. The hinge is formed of two teeth, belonging to
the large valve, which fit into the pits of the lesser.

The animal of the terebratula is nearly allied to that of the
lingula; like it, it has two opposite, elongated arms, fringed,
or ciliated on one side, which it protrudes at pleasure beyond
the shell; when it returns them, they form a double fold from
bottom to top, their extremity only being curved, or rolled ina
spiral form.

The species are divided into recent and fossil, and the former
subdivided into (1) shells smooth, without longitudinal striz,
or furrows, 5 species, and (2) those longitudinally furrowed,
7 species. The fossil species are also similarly subdivided.

Type. Terebratula vitreat. (Anomia vitrea. Gmel.)

Shell ovate, ventricose, glassy, very thin, smooth; larger
beak prominent: perforation small. © Mediterranean. In all
12 recent species, and 47 fossil. Pl. IL Fig. 104.

3. Lingula§.
Shell subequivalvye, flattened, oblong-oval, truncated at the

Norwegian. t Terebratus, pierced, in allusion to the perforation of the
larger valve. t Glassy. § A little tongue.

E 2

52 Lamarck’s Genera of Shells.

summit, slightly pointed at the base; elevated on a fleshy ten-
dinous pedicle, fixed to marine substances. Hinge without teeth.

The animal of the lingula has two arms, and, according to
Cuvier, two hearts. Its two arms are opposite, very long,
fleshy, not articulated, fringed on one side through their
whole length, extensible beyond the shell, and rolled up ina
spiral form when drawn in.

Only one species. Lingula anatina*. (Patella unguis. Linn.)

Shell greenish, resembling in form a duck’s bill. Pedicle
cylindrical, from two to four inches long.

Molucca Seas. PI. 11. Fig. 105. .

Note.—We are indebted to our accurate friend Mr. G. B. Sowerby, for
pointing out a mistake which Lamarck has fallen into, in asserting all the
shells of the family Arcacea to be marine. (See our last Number, p. 317.)
Nueula rostrata, belonging to the 4th genus of the Arcacea, (Arca rostrata,
Gmel.) is called by Schroter, Area fluviatilis, and he says that “‘ it is found
in the rivers of the Coromandel coast.” age Schroter’s Naturgeschiste der Fiuss
Conchylien, wed Mr. Sowerby adds, that he believes there are several
other river arks, but none of them are described by Lamarck, unless A. se-
nilis be, as he suspects, a river-shell.

Art. VI. On a Mode of protecting the Specula of Re-
flecting Telescopes.
[In a Letter to the Editor from Dr. Ure.]
My pDEAR SIR,

I HAVE at present in my possession an excellent seven feet
reflecting telescope, of nine inches aperture, mounted on the
plan of the late Sir William Herschel’s, but furnished with a
curious mechanism for covering up the mirror very closely,
or uncovering it, without opening the tube at the lower end,
as is necessary in using Sir William’s. By this means, it is
completely protected from suffering by moisture in dewy nights,
an accident which we cannot avoid, by carrying the instrument
into an apartment before covering the mirror; for its relative
coldness generally causes an immediate deposition of vapour
on its surface in such circumstances. The mirror of the ten
feet Herschelian belonging to the Glasgow Observatory, was
injured one evening in this way. The following letter and

+ Adj. from anas, a duck.

Dr. Ure on the Speculd of Telescopes. 53

drawing, by the constructors of the instrumert, will explain
more fully the above-mentioned mechanism.

I am, my dear Sir, yours truly,
ANDREw URE.

Sir, Glasgow, 4th March, 1823.

According to your request, we send you a description of the
mode of mounting the large speculum of our telescope.

In one of the Gregorian construction of six inches aperture,
we mounted the speculum on the Herschelian plan, but found
from experience with it at the Glasgow Observatory, as well as
with those made by that admirable astronomer, Sir William
Herschel, that this mode was liable to many objections, being
apt to suffer from dust falling from one’s clothes, or drops of
water from the cover in a dewy night; and its being easily
touched by the finger of those, who were not aware of the mis-
chief which may result to the delicate polish of a speculum
from a moist hand. For the information of such persons as
have not examined Sir William Herschel’s telescopes, it may
be necessary to state, that a portion of the three upper staves
of the octagon-tube is cut through above the speculum, and
hinged in one piece to form a moveable door, of sufficient size
to admit of the speculum cover being readily applied or re-
‘moved.

To get rid of the above-mentioned inconveniences, we fitted
the speculum into a brass ring, furnished with a channel in
front to receive the edge of the cover; the speculum itself
being introduced from behind, and its back fixed in the usual
manner. The lid or cover is formed of three pieces of brass,
neatly fitted and hinged together. They are of such a size,
that when lying down on the sides of the tube, the central
_ segment of the three applies accurately to the inferior stave of
the octagon, and the other two pieces rest inclined on the two
staves to the right and left hand of the bottom one. In this
position, it can intercept none of the light moving in the teles-
_ copie cylinder.

In the same line with the centre of the hinge, a square rod
ofiron is attached to the middle segment of the cover, projecting

54 Dr. Ure on the Specula of Telescopes.
tangentially from it. On thisa key is fitted to the inner surface
of the folding lid, to Which two slender springs are affixed.
When the telescope is placed at an elevated angle, these springs
prevent the lateral segments of the cover from falling forwards,
or striking against the face of the mirror. These springs are
not, however, so stiff as to hinder the cover from folding down
to the wooden surface of the tube by its weight. At the top
of the box, there is a spring catch (detent) fixed, to prevent the
lid from falling off. The speculum box (frame) is attached to
the end of the wooden tube, by resting in a step at the bottom ;
and having two screws to adjust its inclination to the axis, in
the same way as adopted by Sir William Herschel. When in
its place, the prismatic iron rod stands opposite to a hole in
the tube, by which the key is introduced to open or cover up
the mirror. A small sliding plate shuts up this hole.

Fig. 1, represents the speculum uncovered, with the lid
lying against the under surface of the tube. The dotted
lines are a section of the tube. A the speculum, B the box,
C the lid, D the spring catch to hold the lid in its place. E
the square rod, for the key to openit by. Fig. 2, shews the
speculum box shut up, and fixed in the end of the wooden
octagon by the adjusting screws, as at F’.

We are, Sir, your obedient servants,
To Dr. Ure. (Signed,) Joun and Ropert Harr.

Fig. II.

Mr. Harvey on the Formation of Mists. 55

Arr. VII. Experimental Inquiries relative to the For-
mation of Mists. By Grorcs Harvey, Esq., Mem-
ber of the Astronomical Society of London.

Mawry of the results contained in the following paper were
‘obtained in consequence of repeating the interesting experi-
ments on the temperature of air and water, performed by the
President of the Royal Society, during his continental tour,
and which he instituted with the view of tracing the causes
which contribute to the formation of mists over the beds of
rivers and lakes, in calm weather during the night, and an
account of which may be seen in the Philosophical Transactions
for 1819.

It must not be understood, however, that this essay is sub-
mitted to the readers of the Journal of Science, with the slightest
idea that it can in any degree add to the unquestionable ac-
curacy of the principles on which Sir Humphrey Davy has
founded his theory ; and it is, therefore, hoped that it will
merely be regarded as a series of illustrative examples, which
the local facilities of Plymouth and its neighbourhood have
afforded for observations of this kind. These facilities arise
from the elevation of the land surrounding the water, and from
the depth of the river Tamer and of the sea; both of which,
according to a remark of the above philosopher, are essential
conditions, in order to produce a mist of any considerable
density or magnitude. The present year afforded many oppor-
tunities for attending to this interesting subject, and in no case
have I perceived any phenomena at all at variance with the
principles laid down in the paper before quoted.

As this paper, therefore, will contain little more than a re-
gister of facts, they will be detailed nearly in the order in which
they occurred, with the addition only of such observations as
may have a tendency to illustrate the phenomena with which
they are connected. :

Some experimental inquiries, relating to the deposition of
dew, rendered it necessary that the whole of the night of the
27th of April should be devoted to observations connected with

56 Mr. Harvey on the Formation of Mists.

the temperature of the atmosphere, and that of the grass of a
. meadow in which the experiments were performed. To leave
no branch of the subject under consideration unexplained,
thermometers of a very delicate construction, and placed in
different situations, were successively examined every half
hour, from half-past nine in the evening, to nine the next morn-
ing. From the hour first mentioned to four the succeeding
morning, the temperature of the air, at an elevation of seven
feet above the ground, exceeded the temperature of the surface
of the meadow, and the upper sky and the horizon were lucid
and clear. After four, however, an alteration in the aspect of
the heavens, and also in the states of the thermometers, was
perceptible ; and at half-past four the air indicated 393° F., and
the ground 401° F.; whereas, at four, the former was 41° F.,
and the latter 40° F. At this moment a thin haze was visible
by the aid of the twilight, hovering over the marshy lands at
the foot of the meadow, and at five had considerably increased,
both in density and quantity, the temperature of the air at this
moment being 40° F., and the ground 413° F. At halfpast
five A.M., the mist had very much increased, extending
itself into some of the adjacent fields, and having its density
perceptibly greater. A reference to the thermometer also indi-
cated a still greater difference between the temperature of the
air and ground than in the former instances, the air still retain-
ing its temperature of 40°, but the temperature of the grosnd
had increased to 433°. At six A.M., the mist had so much
increased as to obscure the neighbouring town of Stonehouse,
and which had been visible during the former part of the night.
The temperature of the air at six was 414°, and the ground 462°;
and from this hour until nine A.M., the time when the last
observation was made, the ground still continued to possess a
temperature greater by several degrees than the air, and during
the whole time of observation the mist continued of considerable
density.

From the preceding observations it appears, that the quantity
and density of the mist increased in proportion to the excess of
the temperature of the ground above that of the air. One of

Mr. Harvey on the Formation of Mists. 57

the conditions mentioned by Sir Humphry for the formation of
mist in great quantity over water is, that the excess of its tem-
perature above that of air should be as great as possible.

The temperatures of the air and of the ground, at the moment
when the mist was first perceived, were not, however, the maxi-
mum depressions for the night, for at 3 A.M. the air indicated
39°, and the surface of the meadow 38°, These ‘greatest de-
pressions of temperature were perceived just at the moment
when the first golden streak of the dawn had appeared, and
when the particles of dew which had been deposited ‘on the
upper surface of a plate of glass, elevated six inches above the
ground, were completely frozen, the moisture on its under side
remaining in a fluid state. As the entire series of observations
may be acceptable, they are here given.

Temperature
of the
Ground,

Temperature
ofthe Air, 7
Feet above the
Ground.

Temperature

of the
Ground.

Temperature

of the Air, 7 4
Feet above the Time.
Ground.

h. o h o a
94 P.M. 45 48x 34 A.M. 364 40
10 P.M. 411 45 4 aM, 40 41
104 P.M. 431 46 42 a.M. 403 392
11 p.m. 41 432 5 A.M. 414 40
114 p.m. 391 44x 5% aA.Ms 434 40
12 P.M. 39 43 6 A.M: 46x 415

1 AM. 39 40 6 A.M 48 44
1 aM. 4)1 42 7 AM 524 49
1, a.m. 40° 42 7% AM. 53k 51E
2 aM. 40 42 8 A.M. 53£ 50
22 AM: 393 40 8k AM, 572 53
3 A.M: 38° 39 9 AM. 62 57

The night of the 15th of May was dedicated to similar pur-
suits. Observations were made from sun-set to sun-rise, every
quarter of an hour, and in no case was the temperature of the
air found below that of the ground, the nearest approach to a
state of equality having been at 5 A.M., when the warmth of
the air exceeded that of the ground 24°. No mist, however,
was formed during the night on any of the neighbouring sheets
of water, or on the marshy lands below the meadow. The
greatest depression of temperature took place at four, about
twenty minutes before sun-rise, which same hour indicated also
the least temperature of the glass, of a thermometer laying on

58 Mr. Harvey on the Formation of Mists.

the ground, and covered by a glass plate, which rested on its
bulb; also of a thermometer placed on the upper surface of the
glass, and likewise a thermometer placed in the focus of a
thermoscope. The general circumstances of this night were
apparently the same as those of the 27th of April, at least the
deposition of dew and the clearness of the atmosphere bore a
strong resemblance to it; still no mist was perceived, the tem-
perature of the atmosphere having in no case fallen below the
temperature of the ground.

On the 13th of June, at 53 P.M., a mist began to form on
the sea, and in a short time it rapidly extended itself over the
land. The following observations were made of the tempera-
tures of the air and land.

Temperature
Temperature of the Air
5 Feet above

of the Ground.| the Ground.

6}
63
i
9

Maximum Maximum
Cold during Cold during
the Night. the Night.

The mist appeared the greatest at the time the first tempera-
ture was determined, which was about half an hour after it was
first observed. Its density diminished during the two succeed-
ing observations ; and it will be found from an inspection of
the above table, that the excess of the temperature of the ground
above that of the air likewise decreased. At half-past nine, the
mist was changed into gentle rain, the thermometer at the same
time indicating only a difference of a single degree. During the
night, it appears, from the maximum degrees of cold, that the
register thermometer in the air was half a degree higher than
that on the grass.

. At the time the temperature was first observed on the land,
a simultaneous observation was made by a friend, on the sea,
and the results were the following :

Mr. Harvey on the Formation of Mists. 59

| Yemperature

Temperature of the-Air
5 Feet above

of Sea. the Sea.

Temperature
Temperature | of Air 5 Feet
Time. above the
of Land. Land.
Gh, 15/p.m, 70° | 639°

With respect to the observations contained in the last table, it
may be observed, that one of the conditions necessary to the
formation of mist in abundance over the sea, according to
the author of the paper before quoted, is the degree in which
the temperature of the water exceeds that of the air; and it
is not improbable but that the excess of the temperature of
the land above that of the sea, the temperature of the atmosphere
reposing on each being precisely the same, was the cause which
led to the rapid passage of the mist from the sea to the land,
as observed at the commencement of the observations.

For several of the latter days of August, some fine masses of
moving mist were observed, early in the evening, floating over
the sheets of water, and other moist places in the marshes be-
fore alluded to. On the 27th, between eight and nine, a beau-
tiful stratum of it was seen hovering over a part of the stream
which supplies the town with water. The mist moved in the
direction of the running stream, but with a velocity much
greater. It also accommodated itself in a most singular man-
ner, in its course, to all the turns and windings of the channel.
‘The breadth of the moving column was nearly the same as that
of the stream, and its average altitude about five feet. The
following observations were made on it.

Temperature of | Temperature of | Tensperature of

Time. 3 the Air over the tue Ground Temperature of
the Water. Water. near the Mist. | the Air above it,

9 P.M. 56° a7£o 450 4go

60 Mr. Harvey on the Formation of Mists.

The relations of these temperatures are exceedingly curious.
The temperature of the water being greater than that of the air
above it, was the cause of the formation of the mist ;—and the
temperature of the ground being below that of the air which re-
posed on its surface, was also the cause why no mist was ob-
served over its surface. The mass of air over the water was
81 degrees, colder than the stream; whereas the air on the
borders of the channel was 4° warmer than the ground on
which it reposed.

Early in the month of September, at about 2 P.M., immense
masses of mist rolled in from the sea, filling the whole of the
harbour, and covering a portion of the surrounding land. At
three, the greater part had disappeared ; but a fine column of it
was observed in a perfect state of repose, over the bosom of
the creek which runs up to the little village of St. John’s, at
the entrance to Hamoaze. Having taken a boat, for the pur-
pose of performing a few experiments, I found the temperature
of the air near the shore to be 68°, and the water 63°. On
approaching the mist, however, a depression of temperature
was gradually perceptible, and the thermometer was found suc-
cessively to indicate 65°, 64°, and 63°;—and when the boat
was rowed into the centre of the mist, the temperature was
found to be 62°, and that of the water about 635°. On retiring
from the mist, an elevation of temperature was immediately
perceptible, the mercury standing at 64°; and by proceeding to
a still greater distance, the temperature successively increased
to 65° and 67°, being within a degree of what it was on leay-
ing the shore. The column of mist soon afterwards disap-
peared.

On the 13th of November, at 6 A.M., a very dense mist
covered the neighbouring land and water, rising above the
highest of the surrounding hills. At 8 A.M., I had occasion
to cross the river Tamer, the mist still shrouding the whole of
its surface, and that of the adjacent country. The part crossed
was about a mile in breadth, and many opportunities therefore
presented themselves, of estimating the temperatures of the sea
and mist. On the eastern border of the river, the air was 42°;

Mr. Harvey on the Formation of Mists. 61

and for about 300 yards across, the air reposing on the water,
preserved the same temperature. Towards the middle of the
river, however, the temperature of the air was only 41°; but on
approaching the western shore, it was found gradually to in-
crease to 43°. This depression of temperature in the middle
of the mist, most strikingly accords with the view Sir Humphry
Davy has taken of the increase of mists after their first forma-
tion ;—and which he accounts for by supposing, that the in-
crease depends not only upon the constant operation of the
cause which originally produced them, but likewise upon the
radiation of heat from the superficial particles of water com-
posing the mist, which produces a descending current of cold air
in the very body of the mist, whilst. the warm water continually
sends up vapour. The temperature of the river was 53°, both
near its shores, and in the middle.

The land beyond the western side of the river, is hilly and
unequal ; and accordingly the temperature of the air was found
to vary from 43° to 393°. ‘The air in the fields close to the
river was 42°; on higher land it amounted to 43°, and in the
valleys and lower grounds, it varied from 41° to 395°.

At a quarter past nine, the mist still continued, and so dense,
as totally to obscure the sun. The temperature of a rivulet
was found to be 51°, being two degrees colder than the water
of the river; and the air above it 40°, also two degrees colder
than the medium temperature of the air reposing on the Tamer.
At the same moment, the temperature of a meadow was found
to be 44°, and of a ploughed field 46°. At half-past nine the
mist suddenly disclosed the sun, when the air above the same
meadow was found to be 42°, and the green soil 46°. At
noon, the mist had disappeared, and the temperature of the
air, both over the land and sea, was 55°, the river preserving
the temperature of 53°, the same as early in the morning.

During the afternoon of the 10th of June, a dense mist had
formed, which covered the beautiful hill of Mount Edgcumbe,
and also completely concealed from view, the Breakwater, the
ships in the Sound, and Hamoaze. Circumstances prevented

62 Mr. Harvey on the Formation of Mists.

me from attending to it during the afternoon ;—but at half-past
seven, finding the mist rapidly disappearing, I went on the
water, and found, that as the temperature of the air increased,
so the mist diminished. ‘he first observation found the tem-
peratures of the air and water the same, each being 625°; but
when the air incréased to 634° and 64°, the mist melted rapidly
away. This phenomenon accords most perfectly in principle
with the observation made by Sir Humphry during his voyage
on the Danube,—that the disappearance of mist results mi #8
an elevation of the temperature of the air.

Examples have occurred during the past summer, of mists
existing in a very dense state, over water, in the morning, when
the difference in the two temperatures has only amounted to
two degrees ; and in one instance indeed, a remarkably dense
mist was examined, when its temperature was only one degree
below that of the water. To produce a mist, in the first in-
stance, it appears, from the experiments of: Sir H., that the air
must be cooled from three to six degrees below the temperature
of the water. After, however, it has once been formed, it may
exist fora considerable time, after the air has gained such in-
crements of heat, as to reduce the difference between the tempe-
ratures of the air and water to a very small quantity. Between
the first formation of a mist, and its final disappearance, it is evi-
dent, from the principles laid down, that a moment must exist,
when the temperatures of the air and the water will exactly coin-
cide. Before this period, the principle which promoted the forma-
tion of the mist, may sometimes continue in operation, but with
a diminished activity, until an equality of temperature is at-
tained ;—but after this, the mist will disappear, with a rapidity
proportional to the magnitude of the increments which the at-
mosphere may receive. The continuance of the mist (omitting
the consideration of the radiation of heat from the superficial
particles of water composing the mist) must be regulated by
the difference between the temperature of the air and water;
and which, from the diversified nature of our atmospheric
changes, will be exceedingly varied and uncertain.

Mr. Harvey on the Formation of Mists. 63

The following table contains an abstract of some results
recorded, at my request, by a scientific friend *, and which
perfectly accord with the luminous views of Sir H Davy.

Month and |Temperature of|Temperature of REMARKS,
Day. Air. Water.

—_

June 11 59 a 63 Thick mist.
August 3 59 59 Thick mist.
Ly age 52 59 Thick mist.
6 54 59 Moderate mist.
7 56 59 Thin mist.
8 54 60 Mist and gentle rain.
28 58 62 Do. do.
31 493 611 Very dense mist.
Sept. 3 573 61 Thin mist.
Ge eRe: 56 nt Thin mist. " ad
10 53 593 Dense mist.
‘12 54 60 Do. do.
24 58 59 Very dense mist.
28 51 i. Dee Moderate mist.
Oct. 4 53 593 Very dense mist,
Il 48 55 Moderate mist.

15 463 57 Very dense mist.

All the preceding observations were made at 7 A.M., excepting
the first, which was at 6 A.M.

Some instances also have occurred, to illustrate a remark
made by Sir H. Davy, that a current of dry air passing across
a river will prevent the formation of mist, even when the
temperature of the water is much greater than that of the at-
mosphere; and he adduces an example of the Danube haying
no mist on its surface, when the temperature of the river was
61°, and the air only 54°; the cause of which he attributes to
the prevalence of a strong easterly wind. The following are
some examples which occurred during the past summer :—

a a

Month Temperature Temperature
and of of REMARKS.
Day. J Air. Water.
Oo [eo] -
July 13 58 61 Atmosphere clear. Gale from N.E,
30 58 63 Atmosphere clear. Gale from E,
Sept.14 56 59 Cloudy. Gale from E.
19 53 60 Clear. Gale from E.
21 54 59 Cloudy. Brisk Gale from E. *

These observations were also made at 7 A.M.

* Mr, George Pridham.

64 . Mr. Harvey on the Formation of Mists.

It may also be added, that the temperature of the air is
sometimes considerably less than that of water, during rain.
The following are instances :

\Temperature/TempPperature
of o

REMARKS.
Air.

Water.

——
July 26 | 603 621 | Clouds with Showers.
31 523 62 Heavy and frequent Showers.
August 2 54 59 Clouds with Showers.

The example of the 31st of July, exhibits a remarkable dif-
ference in the temperatures of the air and water.

Arr. VIII. On the Light produced by the Discharge of
an Atr-gun:

To the Evitor of the Quarterly Journal of Science and the Arts.

Sir,

Amon the various methods of producing light, taken notice
of by philosophical writers, that from the discharge of the air-
gun has not escaped observation. It is asserted that a flash
of light is seen at the muzzle of the air-gun, when it is dis-
charged in the dark. This light is supposed to be electric,
and to be produced by the sudden expansion of the condensed
air in the atmosphere. Having often attempted to produce
light in this manner without success, I varied the experiment
by introducing successively warm, dry, and damp air; and
discharging them in moist, dry, frosty and warm atmospheres ;
but always without succeeding in the production of light. Lest
the barrel of the gun might be supposed to absorb the electric
fire, I discharged the spherical magazine itself by striking
with a hammer on the valve, but still without the expected
success.

One evening last autumn, while discharging the same gun,
during twilight in a back court, I observed for the first time a
faint light. I now concluded that it must be from the wadding
exciting friction on the inside of the barrel (all the former
experiments having been made with an unloaded gun). But, as

On Light produced by the Discharge of an Atr-cun. 65

{ could not re-produce the light that evening, I imagined that
the first wadding (made of paper,) had been drier and a better
electric. .

I now tried dry silk, woollen, feathers, paper, rosin, shell-lac,
sugar, as well as tubes, and narrow slips of glass.

The first three and shell-lac occasionally produced light;
Sugar and glass never fail to do so; but that from the glass
was by far most vivid, affording a stream of bright greenish-
Coloured light, extending about a foot in length from the
muzzle. Imagining that it was the velocity with which the
electric substance was driven through the air that occasioned
the phenomenon, I enclosed small lead shot, peas, &c., in
pieces of silk, leaving a tag of silk behind. By this con-
trivatice I expected to produce a luminous stream, but I could
perceive no light whatever from any of them.

The preceding experiments were made in the cellar of a
half-finished house. I repeated them before sore friends on
the followiig evening, with the same success. But what
was our surprise on trying some of the old silk wadding,
which had become damp and dirty from lying on the floor
Since the last night’s experiments, to find them yield a much
more luminous appearance than before; and; that small
pieces of split lath, and even damp saw-dust picked up off
the floor, likewise afforded light. We now tried the gun
empty or without a charge in its barrel, when we found it
always to give light at the first shot, after the magazine was
charged; and this took place whether the charge was high
or low. .

My brother remarked that some particles of lime or sand
might possibly fall into the barrel, as the gun was rested
against the wall, during the time that the magazine was
charging ; the attrition of which particles might probably be
the cause why the first discharge appeared lumiiious. Ac-
cordingly, on taking precautions against this accident, no light
Gould be obtained: But on introducing a little sand, a beautiful
Stream of light was seen at every discharge.

It was now evident that the light was produced by attrition,

Vor. XV: F

66 On Light produced by the Discharge of an Air-gun.

and that the sand adhering to the split lath, saw-dust, silk, &c.,
might be the real cause of the light. We next tried pieces of
very clean and dry silk, wool, feathers, and cylinders of wood,
carefully freed from sand, and found that no light could be
excited by their means.

Finally satisfied that attrition was the sole cause of the
luminous appearance, we tried siliceous and other hard bodies,
which emit light on being rubbed together, such as quartz,
fluor-spar, &c., and found them all to be luminous. From
bodies of an opposite nature no light could be elicited. To
ascertain whether the light from these hard substances
might arise from small particles of iron torn from the sides of
the barrel, like sparks from a cutler’s wheel, we held sand,
fragments of spar and sugar successively in our hands, at the
muzzle of the gun, and discharged it at them. In this way
they all appeared luminous, though not so bright as when dis-
charged from the barrel. To see whether it might not be an
electrical appearance, arising from the air being violently
blown against these crystalline bodies, we formed a small
grating of clean and well-dried thermometer tubes, which we
held as before, opposite to the muzzle of the gun; but could in
this case perceive no luminous appearance whatever from dis-
charges of condensed air passed through them.

Hence it may be concluded that light emitted on the dis-
charge of an air-gun arises solely from attrition, occasioned by
sand or other hard substances adhering to the wadding, or
getting by accident into the barrel; and, that no light-can be
produced from the sudden expansion of the air from a con-
densed magazine, or from its impulse on the still atmosphere*.
By introducing sugar into the gun and discharging it against
a wall in the dark, a flash of light is seen to proceed from the
sugar, as it strikes the wall.

; - (Signed) Joun Harr.

* The light which M. Biot says is extricated when we cause a glass
globe filled with air to burst in vacuo, must be ascribed to the friction of
the particles of the broken glass on each other.

67

Arr. IX.—Details of a Barometrical Measurement of
the Sugar-loaf Mountain at Sierra Leone, and of other
Heights situated within the Tropics. In a Letter from
Captain Enpwarp Sasine, of the Royal Artillery, to
J.F. Dante nt, Esq.

MY DEAR SIR,

I have much pleasure in communicating to you the accom-
panying detail of a barometrical measurement of the height of
the Sugar-loaf Mountain at Sierra Leone, because I am enabled
to add in comparison, the result of a geometrical determination
of the same, which has been accomplished since I quitted
Africa.

The Sugar-loaf, so called from its shape, is the highest point
of the mountain district of the colony, included as yet within
the limit to which cultivation has extended. This district, as
you are aware, is the site of the twelve most interesting settle-
ments of liberated Africans, from the principal of which, Re-
gent-town, it is distant about three miles, being altogether
about eight or nine from Free-town, the seat of government :
a road has been opened by the inhabitants of Regent-town, by
which the summit is accessible, and has been sufficiently cleared
of its forest-trees to admit the view around. In the continua-
tion of the Sierra towards the south, at about 20 miles distance;
the land appears to attain a greater general elevation than in
the neighbourhood of the Sugar-loaf, and there are several
points, especially, which are probably much higher; to these
there is as yet no road, but from the very rapid advance which
the colony is making in population and in settlement, it cannot
be doubted that these points must very shortly be necessarily
included in the Colonial Survey.

Dr. Nicol, deputy-inspector of army hospitals, was kind
enough to allow me the use of a stationary barometer, in ex-
cellent order, made by Cary, and the property, I believe, of the
College of Physicians; it is the same instrument which has
since accompanied Captain Laing in his very interesting ex-
cursion to the Soolima country, in which the Niger takes its

F2

68 Barometric Measurement of Sugar-loaf Mountain,

rise, and which has enabled him to ascertain satisfactorily the
elevation at which that river originates its yet unknown course.
The accordance of the portable barometer with the stationary
was examined before and after the observations for the measure-
ment; the latter was placed in the room in Fort Thornton, in
which my pendulum experiments were made, and its height,
consequently, above half tide, carefully ascertained by levelling;
was known, with tolerable precision, to be 190 feet; the varia-
tions in the density and temperature of the atmosphere, and in
the point of deposition of moisture as indicated by your hygro-
meter, were observed at this spot by Captain Laing; at stated
periods with a chronometer, on the 28th of March, so as to be
simultaneous with such as should be made at elevations.

I shall confine myself to stating the data necessary for the cal-
culation of the heights of the clergyman’s house at Regent-town,
and of the summit of the Sugar-loaf. At the first of these sta-
tions, the barometer, having been suspended above an hour five
feet below the gallery which surrounds the clergyman’s house,
shewed at 7 A.M. on the 28th March, 29.017 in., th. 74°.5, and
the point of deposition 57°; the corresponding observations at
Fort Thornton were 29.820 in., th. 79°.5, and the point of depo-
sition 66°. At 11 A.M. on the same day, the barometer being
suspended in the shade, at the summit of the Sugar-loaf, the
cistern 14 feet below the highest point, was suffered to remain
until 12 o’clock, that the mercury might acquire the tempera
ture shewn by the attached thermometer ; when the observations
registered were 27.560 in., th. 82°.2, and the dew point 70°,—
those at Fort Thornton being 29.795, th: 84°, and the dew
point 70°, also.

The mercury beg reduced to the same temperature at the
upper and lower stations, and ; of the differences in the
heights of the column being added on account of the respective
diameters of the tube and cistern of the barometer, the true
differences are, between Fort Thornton and Regent-town .8 in.,
and between Fort Thornton and the Sugar-loaf 2.263 in., at the
temperatures of the air, and under the pressure of the amount
of atmospheric vapour specified above. The approximate heights

at Sierra Leone, by Captain Sabine. 69

due to these differences being corrected for the latter circum-
stances, in the manner and agreeably to the tables which you
have given in the XXVth Number of the Quarterly Journal of
the Royal Institution, it results that the floor of the gallery of
the clergyman’s house at Regent-town is 983.6 feet, and the
summit of the Sugar-loaf, 2521.6 feet above the sea.

_ Ihave taken the liberty to add (though without permission) an
extract of a letter which I have received, since my return to Eng-
land, from Thomas Stuart Buckle, Esq., engineer and surveyor
of the colony, stating the result of a comparative geometrical
measurement. “I was much gratified to find, on computing the
altitude of the Sugar-loaf, from the trigonometrical observations
that I had taken, that the result differs from your barometrical
measurement only a few feet; I make its height 2493 feet: the
height of Leicester Mountain I computed to be 1954, and it
was sufficiently satisfactory, on taking into account the dis-
tance of the Sugar-loaf from Leicester Mountain, and the ex-

“cess of its height above that of Leicester Mountain, that the
result of the latter was 537 feet, which, added to 1954, amounts
to 2491, differing from the former calculation only two feet.”

I have added the barometric measurements of well-known
places in the islands of Ascension, Trinidad, and Jamaica; but I
am not aware of any previous results with which to compare them.

Height of the Mountain-house at Ascension.—July 9th, 1822,
at 9° 30" A.M., a barometer, 17 feet above the sea, in a room
in the Barrack-square at Ascension, stood at 30.165 in., the
temperature of the air and mercury being 83°, and of the point
of deposition 68°; whilst, at the same time, another barometer
three feet above the floor of the Mountain-house, stood at
27.950 in., the air and mercury 70.3, and the point of deposi~
tion 66.5. From these data, the floor of the Mountain-house
would appear 2221.8 feet above the sea.

The upper barometer was then taken to the summit of the
island, but the registry at that height has been mislaid; it was
27.3 and some hundreds, being less than 700 feet aboye the
Mountain-house ; consequently, the highest part of Ascension

70 Barometric Measurement of Sugar-loaf Mountain,

is under 3000 feet: on returning from the summit, the barome~
ter was replaced three feet above the floor of the house, and
allowed to remain until the mercury should have acquired the
temperature of the air, when, at 1» 30m P.M., its height was
27.937 in., air and mercury 72°, point of deposition 68°, and
in the lower barometer 30.137 in., air and mercury 84.5, point
of deposition 71°, whence the height of the floor of the Moun-
tain-house results 2219 feet above the sea, being three feet less
than the first measurement. The mean, consequently, or 2220.5
feet, is considered the correct elevation.

Height of the Block-house at Fort George, Trinidad.—Octo-
ber 9th, 1822, at 82 30™ A.M., a barometer, 4} feet above the
foundation of the Block-house, stood at 29.000 in., the air and
mercury being 76.5, and the point of deposition 76.5 also, with
slight rain. The corresponding height of the barometer, at the
same time, in the Protestant church in Port Spain, 20 feet
above the sea, was 30.058 in., air and mercury 82°, and the
point of deposition 77°. Whence the foundation of the Block-
house would appear 1067 feet above the sea.

Height of Mr. Robert Chisholm’s house, in the Port-Royal
Mountains, Jamaica.—October 31st, at 4"30™ P.M., a barome-
ter, suspended against the wall of Mr. Chisholm’s house, 2 feet
above the ground, stood at 25.967 in., the air and mercury being
68.5, and the point of deposition 68.5 also; and on the 2d of
November, at 6 A.M., at 25.963 in., the air and mercury 65°,
and the point of deposition 60°. The corresponding observa-
tions at Port Royal, at the same hours, 8 feet above the sea,

were—
Oct. 31,—Bar. 30.007; Air, 82.5; Mere ., 84.5; Dew point, 77
Nov. 2, ,, 30.023 78. 78. 72

Whence the height of the ground on which Mr. Chisholm’s
house stands, results respectively, 4087.9 feet, and 4072.7 feet,
the mean being 4080.3 feet above the sea.

All the observations at heights were made with the same
portable barometer; ;4;, therefore, is added throughout to the
barometric differences on account of the ratio of the diameters of
the tube and cistern. The height of the column of mercury, in the

at Sierra Leone, by Captain Sabine. 71

upper and lower barometer, under equal pressure, was in all
cases carefully examined, and the difference, if any, allowed as
an index error to the lower barometer. I have great pleasure
in remarking, that I found much less difficulty than I had an-
ticipated, in getting corresponding observations made with the
hygrometer, on the correctness of which I could sufficiently
depend; the ingenuity in the principle of this instrument, and
the simplicity of its application, together with the decisive na-
ture of the results which it gives, independent of the labour, and
at best, the uncertainty of formulaic deduction, form its great
advantage over the methods by evaporation, or the indications
of hygroscopic substances: these particulars excite an interest in
its trial in persons to whom it was previously unknown, which is
probably the reason that the distrust, which is almost always
in the first instance expressed of precision in the observation
itself, is found to give way in practice so much sooner than
might be supposed. It may be useful, also, to travellers in warm
climates, to add a remark from my own experience, that in as-
cending elevations, or in journeying inland over rough roads,
the ether carries perfectly well in a bottle in the waistcoat
pocket, with a common cork capped with leather; and that the
expenditure of ether altogether will probably fall much short
of the estimate, as, with ordinary care, very little will be

wasted.
Believe me, my dear Sir,

Very sincerely yours,

Epwarp SaBINeE.
Lonpon, March 17, 1823.

Art. X. On Hydrate of Chlorine. By M. Farapay,
Chemical Assistant in the Royal Institution.

Iv was generally considered before the year 1810, that chlo-
rine gas was condensible by cold into a solid state; and we
were first instructed by Sir Humphry Davy, in his admirable
researches into the nature of that substance, published in the
Philosophical. Transactions for 1810-11, that the solid body,
obtained by cooling chlorine gas, was a compound with water ;

72 Faraday on Hydrate of Chlorine.

and that the dry gas could not be condensed at a temperature
equal even to—40° Fahr., whilst, on the contrary, moist gas, or
a solution of chlorine in water, crystallized at the temperature
of 40° Fahr.

M. Thenard, in his Traité de Chimie, has described the depo-
sition of the hydrate of chlorine by cold from an aqueous solu-
tion of the gas. It forms crystals of a bright yellow colour,
which liquefy when their temperature is slightly raised, and in
so doing give off abundance of gas.

This substance may be obtained well crystallized, by intro-
ducing into a clean bottle of the gas, a little water, but not
sufficient to convert the whole into hydrate, and then placing
the bottle in a situation the temperature of which is about or
below freezing, for a few days: and I have constantly found
the crystals better formed in the dark than in the light.
The hydrate is produced in a crust or in dendritical cry-
stals; but being left to itself, will in a few days sublime
from one part of the bottle to another in the manner of cam-
phor, and form brilliant and comparatively large erystals.
These are of a bright yellow colour, and sometimes, though
rarely, are delicate prismatic needles extending from half an
inch to two inches into the atmosphere of the bottle: gene-
rally they are of shorter forms, and when most perfect and
simple, have appeared to me to be acute flattened octoédra, the
three axes of the octoédron having different dimensions.

Though a solution of chlorine deposits the hydrate when
cooled, yet a portion remains in solution, and the crystals also
dissolve slowly in water. It is, therefore, soluble, though not
so much so as chlorine gas. When a solution of chlorine is
cooled gradually till the whole is frozen, there is a perfect sepa-
ration of the hydrate of chlorine from the rest of the water, or
rather from the ice; for crystals of ice, formed in a solution of.
chlorine, when washed in pure water, and then dissolved, do
not trouble nitrate of silver.

I neglected to ascertain the specific gravity of the crystals
whilst the weather was cold and they were readily obtainable ;
but, I have endeavoured since to do so by means of cooling

Faraday on Hydrate of Chlorine. 73

mixtures. The hydrate in thin plates, was put into solutions
of muriate of lime of different densities, but of the temperature
of 32° Fahr. It seemed to remain in any part of a solution of
specific gravity 1.2, but there was constantly a slight liberation
of gas; and, as minute and imperceptible bubbles may have
adhered to the hydrate, the result can only be considered as a
loose approximation, The solid erystals would probably be
heavier than 1.2.

The hydrate of chlorine acts upon substances, as might be
expected, from the action of chlorine upon the same substances,
and it may perhaps now and then offer a convenient form for
its application in experiment. When put into alcohol, an ele-
vation of temperature amounting to 8° or 10° took place.
There was rapid action, much ether, and muriatic acid formed,
and a small portion of a triple compound of chlorine, carbon
and hydrogen.

When put into solutions of ammoniacal salts it liberated
nitrogen gas, formed muriatic acid, and also chloride of
nitrogen, which remained undissolved at the bottom of the
solution. In aqueous solution of ammonia similar effects were
produced, but less chloride of nitrogen was formed.

In order to arrive at a knowledge of the composition of this
substance, I adopted the following process. The crystals were
collected together by a small quantity of solution of chlorine,
then filtered and pressed between successive portions of bibu-
lous paper, at a temperature of 32°, (care being taken to expose
them as little as possible to the air,) until as dry as they could
be rendered by this means. A glass flask with a narrow neck,
and containing a portion of water at 32°,having been previously
counterpoised, a portion of the crystals were immediately after
the last pressing introduced into it; they sank to the bottom
of the water, and the flask being again weighed, the quantity
of crystals introduced was ascertained. A weak solution of
pure ammonia was then poured on the water in the flask, care
being taken to add considerable excess over that required by
the chlorine beneath. The whole was left for twenty-four
hours, in which time the chlorine had had sufficient op-

74 Faraday on Hydrate of Chlorine.

portunity to act on the ammonia, and any portion of chloride
of nitrogen that might at first have been formed would be
resolved into its elements, and its chlorine be converted into
muriatic acid. It was then slightly heated, neutralized by pure
nitric acid, precipitated by nitrate of silver, and the chloride
of silver obtained and weighed.

The following is an experiment conducted in this way: 65
grains of the pressed crystals were put into the flask, and the
ammonia added ; at one time there was a faint smell of chloride
of nitrogen for an instant at the mouth of the flask, and a little
more ammonia was added. The next day 73.2 ers. of chloride of
silver were obtained from the solution, and if this be considered
as equivalent to 18 grs. of chlorine, then the 65 grs. of hydrate
must have contained 47 ¢rs. of water, or per cent.

Chiotiné . 2.) 27.7
Water AP 2 PRS 72.3:

This nearly accords with 10 proportionals of water to 1 of
chlorine, and I have chosen it because it gave the largest pro+
portion of chlorine of any experiment I made. It is evident
that any loss or error either in the drying the crystals, or in
the conversion of the chlorine into muriatic acid by the ammo-
nia, would tend to diminish,the proportion of that element, and
it is even possible that the above proportion of chlorine is
under-rated, but I believe it to be near the truth. The mean of
several other experiments gave

Chlorime.“¢.) ) &3"' 26.3
Water | «is. ei9 03 {43Gb

Note.—Since writing the above, Mr. Faraday has succeeded in condensing
chlorine into a liquid : for this puaase a portion of the solid and dried hy-
drate of chlorine is put into a small bent tube and hermetically sealed ; it is
then heated fo about 109, and a yellow vapour is formed which condenses
into a deep yellow liquid heavier than water, (sp. gr, probably about 1.3),
Upon relieving the pressure by breaking the tube, the condensed chlorine
instantly assumes its usual state of gas or vapour.

When perfectly dry chlorine is condensed into a tube by means ofa
syringe, a portion of it assumes the liquid form under a pressure equal to
that of 4 or 5 atmospheres.

By putting some muriate of ammonia and sulphuric acid into the oppo-
site ends of a bent glass tube, sealing it hermetically, and then sufferin z
the acid to run upon the salt, muriatic acid is generated under aneh
aie as causes it to assume the liquid form ; it is of an orange-colour,

ighter than sulphuric acid, and instantly assumes the gaseous state
when the pressure is removed. Sir H, Davy has given an account of this

experiment to the Royal Society. Itis probable that by a similar mode of
treatment several other gases may be liquefied.

75

Art. XI. An Account of a Baromeirical Measurement of
the Height of the Pico Ruivo, in the Island of Madeira.
Extracted from a Letter written by Captain Epwarp
SaBineE, of the Royal Artillery, to Sir Humpury
Davy, Bart., President of the Royal Society, dated in
January, 1822, on board his Majesty's Ship Iphigenia,
on passage between the Cape Verd Islands and Goree:

_ “ You are probably aware that the mountainous parts of

the interior of Madeira have been rendered accessible to a
greater distance than formerly, by roads of recent construction,
passable at most seasons by mules, or by the small horses of
the island, which vie with mules in the sureness of their foot-
ing. I availed myself of the opportunity which our short stay
afforded, of making an excursion to the summit of the Pico
Ruivo, the highest of the island, with a view to obtain a mea-
surement of its height, and to make a first essay with a portable
barometer having an iron cistern, on which Mr. Newman had
bestowed much pains, to obviate the liability to the various
errors to which these instruments are generally subject. The
party consisted of Captain Clavering, of his Majesty’s ship
Pheasant, Mr. Whitelaw, surgeon of the Iphigenia, Mr. George
Don, naturalist of the Horticultural Society, and two mid-
shipmen of the frigate; we were accompanied by Mr. Black-
burne, an English merchant resident at Madeira, who, having
before ascended the Peak, was kmd enough to undertake to
conduct us, and by his local knowledge and authority over our
Portuguese attendants and guides, as well as by his own enter-
prising spirit, enabled us finally to accomplish our purpose.
Lieutenant Stokes, of the Iphigenia, was so kind as to remain
on board the frigate throughout the day, to note the variations
in temperature and density of the atmosphere, and of the point
of deposition indicated by Mr. Daniell’s hygrometer. These
were observed hourly by a chronometer, so as to be simultane-
ous with others which we should make at the heights at which
we might find ourselves. I shall detail the observations, and

76 Barometrical Measurement of the

their computed results, at the close of the letter, and purpose
to give you a slight sketch of our route, such as may possibly
be useful to persons desirous of making a similar excursion.

We quitted Funchal before day-break, and proceeded about
six miles along the coast to the westward to Camera de Loubos,
from whence we commenced the ascent in a northerly direc-
tion. At eight we stopped to breakfast at the Jardim de Serra,
a house which Mr. Veitch, the British consul-general, has built,
at an elevation of nearly 2800 feet. In approaching this height,
the vegetation reminded us at every step of England; the
people of the country, whom we met on their way to mass, im-
pressed us favourably by their courteous demeanour towards
each other, as well as to strangers; they were well, and even
handsomely clothed ; the men able-bodied and good-looking,
but the women, almost without exception, very plain.

We found the temperature at Mr. Veitch’s 16° less than at
Funchal, being a much greater difference than we had expected
as due to the elevation. An ascent of about half an hour from
the Jardim opens the first sight of the Curral, which struck
me, who am, however, but little accustomed to mountain
scenery, as the most magnificent view I had ever seen; the
Curral das Freiras, which means literally,"I believe, the Sheep-
fold of the Nuns, is a ravine extending several miles in a north
and south direction, and of considerable width, the sides ex-
tending four thousand feet in height, in character frequently
precipitous, and where so, being in fine contrast with the deep
green foliage of the trees, by which the sides are more gene-
rally clothed; these trees are principally laurels, amongst
which we noticed the Nobilis, Indica, and Feetens. The valley
of the Curral is occupied by @ small river, which descends
from the high land of the interior with all the character of a
mountain torrent. Our route led into the Curral for the pur-
pose of ascending its valley, but the descent being impracti-
cable at the spot where the first view is obtained, the road
continues to ascend, passing over an elevated ridge, on which
there was much snow. In descending on the Curral side of
this ridge, and at some distance beneath its summit, is a copi-.

Pico Ruivo, by Captain Sabine: 17

ous spring, which collects in a shaded basin formed in the rock
by the workmen by whom the road was made. The tempera-
ture of the water in this basin was 47°.2, that of the air 46°,
and at Funchal 65°; its elevation 4454 feet:

Whilst these observations were making, the summit of the
Pico Ruivo, which was enveloped in clouds during the day, was
visible for some minutes ; and it may be worthy of notice; that
this was the only period in which the proportion of moisture in
the upper air to saturation was observed to be less than at
Funchal. The wind throughout the day was easterly and light,
but with little of the unpleasant sensation which usually charac-
terizes the Leste.

The time pressing, we committed our horses to the Portuguese
attendants, and descending ourselves on foot more quickly than
we should have done on horseback, although stopping occasion-
ally in admiration of the splendid scenery on every side, which it
was impossible to pass without notice, we crossed at noon the
Ribeiro di Curral on a tree which had fallen across the torrent;
the horses fording it lower down; and pursued a road which
led to the head of the valley. We there recommenced the ascent;
and passing through districts of brooms and ferns; entered the
snow at a somewhat lower elevation than on the heights near
the coast. At two P.M. we reached the highest point attainable
on horseback, by reason of the depth of snow, and of the
frequent quebradas, or breaches, in the road, caused by the
descent of torrents. It is a ridge 4380 feet above the sea, over
which the road passes at the foot of the Pico das Torrinhas,
which is inferior in height only to the Pico Ruivo. From hence
Mr. Whitelaw and myself proceeded on foot, the others of our
party returning to the valley to await us. Entering athiek wood
of evergreens, consisting of laurels, of the Quercus Ilex, and of
the Erica Arborea which attains a large size and grows even at
the summit of the mountains, we were soon enveloped in the
clouds by which the Peak was hid from our sight; and after
an hour anda half’s good walk through snow, which latterly ex-
ceeded two feetin depth, impeded occasionally by the quebradas,
which are passable only by the aidof roots and branches of trees,’

78 Barometrical Measurement of the

and not without danger, as a slip unrecovered would generally
be fatal, we attained the summit. We experienced no other
inconvenience than being wet by the rain, and a little cold,
whilst we remained to make the necessary observations to
ascertain the height; certainly none that need deter others from
a similar undertaking at the same season of the year, when,
should the weather be clear, they will be amply repaid. The
Peak being nearly in the centre of the island, the view, from it
must be very splendid, though of this we were only able to
form an imperfect judgment from the unfavourable cireum-
stances of the weather. It is not otherwise interesting than
as relates to its height and situation, being merely one of se-
veral pinnacles in an island of volcanic formation.

It was dark before we had rejoined our party in the valley.
We had then to reascend the opposite side of the Curral to
that which we had descended in the morning, in order to gain
a nearer road to Funchal than by the Jardim de Serra. This
ascent was more precipitous than any we had yet traversed,
and made those amongst us feel nervous who had not learned
from habit to confide in the sure-footing of the horses, inas-
much as, during the greater part of the way, a single false step
would have precipitated the horse and rider many hundred
feet into the valley beneath; the apprehensions of danger
were perhaps augmented by the accompaniment of torch-light;
and induced some of the party to trust to themselves rather
than to the horses; we all, however, reached Funchal in safety
by midnight. Lyi

The barometer was found to answer extremely well, both
in conveyance and in use. I am not aware of any objection
to the iron cistern to counterbalance its many advantages
over those of leather or of wood, the former of which are es=
pecially faulty in being affected by damp, whilst the certain
freedom of the mercury from air and moisture in barometers of
this construction, give them a decided preference over thosé
which are filled on the spot, and which I cannot consider as
otherwise than very uncertain. Iregret extremely that I have
not to occupy your attention with the more important relation of

Pico Ruivo, by Captain Sabine. 79

its performance in the ascent of the Peak of Teneriffe, but our
departure from England had been so long delayed by contrary
and tempestuous winds, that we were only able to remain seven
hours at Santa Cruz. We were told, indeed, that the Peak
was inaccessible in the winter season, but we had heard the
“same at Funchal of the Pico Ruivo. I am aware that the
difficulty in the two cases does not admit of comparison, but
the true interpretation is, that neither is accessible without
more exertion than travellers are ordinarily disposed to bestow.
Had Sir Robert Mends felt at liberty to have remained at Tene-
riffe for three days, we should certainly have made the attempt,
and as Captain Baudin succeeded in December, I trust we
should not haye failed in ‘January. The precise determina-
tion of the height of this peak is yet to be accomplished,
and appears worthy of being undertaken, were it only to sub-,
mit barometric measurement to the test of a mvre exact com-
parison with the geometric method, (both conducted with
the precision of which modern instruments are capable,) than.
has yet been effected. A residence of some days at the pro-
per season, near the summit of this remarkable Peak, which
rises so abruptly, and to so great an elevation, from the middle
of the basin of the Atlantic, might indeed be expected to pro-
duce many important meteorological and other results; and
would certainly throw much light on the extent of variation, to
which barometric measurement is liable, from varying cireum-
stances connected with the atmosphere itself, independently of
errors of instrument or observation, or of the formula by which
a.result is deduced ; the limit within which this liability might
be apprehended would appear, by a comparison of the registry
of the barometer at the top and at the bottom, continued for a
Sufficient time,

We experienced a similar disappointment, and scarcely iman
inferior degree, in passing hastily by Fuego, one of the Cape
Verds, I am not aware of any good account of this very re-
markable island having been published, and am surprised that
it has been so little visited. It-rises in a cone almost from the
water’s edge to an height much exceeding that of St. Antonio,

86 Barometrical Measurement of the

which is estimated by Captain Horsburg at 7400 feet, and we
had redson to conclude, from the angle which it subtended at
different distances, justly estimated. The summit of Fuegt was
visible from the ship for two days, rising much above the clouds,
and always clear; no smoke proceeded from it, although ‘it is
said to be generally burning. I cannot conceive a station
more eligible for interesting experiments, connected with the
relations of heat arid moisture to the atmosphere.

I take this occasion to bring under your notice an inaccurate
practice which prevails in our directories, and even in works
of higher authority, of stating the geographical position of a
bay, anchorage, or town, generally, instead of specifying some
particular bearing in the anchoragé, or spot on the shore.
Madeira affords an instance which is quite in point. It is re+
corded in the directories that Captain Flinders found Funchal
Bay in 16° 55°24” W. longitude, and Captain Heywood in
16° 51‘; [believe that it is just possible that a difference of
longitude equal to the disagreement, may be comprised within
the limit of the bay, or nearly so, although it is more probable
that a considerable portion of it at least ig due to an actual
difference between the captains, than to the distance apart of
their respective anchorages. The present notice of the direc-
tories may be sufficient to enable ships to find Funchal Bay;
but it does not supply a means of comparing chronometers with
correct Greenwich time, which is so important to navigators,
especially at a port frequently touched at by ships bound on
distant voyages. The usual passage from the ports of the
Channel to Madeira is from sever’ to ten days, an uncertainty
therefore amounting to two miles in the part of the bay for
which the longitude is assigned, and which is well within the
limit of the anchorage, makes a corresponding doubt in the
time of eight seconds, or nearly a second a day in the rate
of the chronometer; an uncertainty which is of great mag-
nitude, when it is remembered that whatever error it oc-
casions, is multiplied in the subsequent voyage by as many
times as the number of days between England and Madeira are
tepeated. It would be very desirable that the geographical

Pico Ruivo, by Captain Sabine. 81

tables in works of authority, such as in the Connoissance des
Tems, and in Professor Lax’s Nautical Tables, should have an
additional column, specifying the spot to which the latitudes
and longitudes refer ; it is otherwise quite unnecessary to give
these data to seconds of space.

The precise geographical determination of some one spot in
Funchal is still a desideratum, which I was in hopes of sup-
plying by a sufficiency of lunar observations, could another
day have been spared me. I may state, as an approximation,
that the result of 64 distances, 40 of Regulus west, and 24 of
the Sun east of the Moon, observed in the Consul’s house, made
its longitude 16° 55’ 00” W.; that the three chronometers of
Parkinson and Frodsham, on which I placed principal reliance,
made it respectively as follows :

° ‘ 4“

No. 384, ie 57 05 By observations in the fore and after-
493, 16 57 08 noon, and using the rates at which they
423, 16 56 39) jag gone in England.

Mean, 16 56 67|

——_Y

and that the mean of all the chronometers I had with me, (except
Brequet’s whose rate had altered considerably,) made the
longitude 16° 56” 30.”

Norte.—Since this letter was written, Madeira has been visited by his
Majesty’s ships Leven and Barracouta, on their passage to survey the
eastern coast of Africa, under the command of Captain Owen. By the
chronometers on board these ships the difference of meridians between the
Marine Observatory at Lisbon, and the Loo Fort in Funchal Bay, ap-
peared 7° 48’ 09”, whence assuming the Observatory at Lisbon at 9° 08’ 51”
W., the Loo Fort would be in 16° 57’ 00”.—And finally, the longitude of
the Consul’s garden at Funchal has been determined by a mean of sixteen
chronometers, specially sent for the purpose, at the direction [of the
Commissioners of Longitude. It is understood that their mean result
made the garden in 169 54/52’.5 W. The three stations are all withina
second of time.

“<I conclude with a detail of the observations, and the heights

computed from them.
Vor. XV. G

82 Measurement of the Pico Ruivo, by Capt. Sabine.

eee
OnsERVATIONS made at Maverra, January 13, 1822, to deter-
mine the elevation of several Stations in the ascent to the Pico

Ruivo.

UE EET
Corresponding Observations

Observations at the Station. 8 feet above the Sea.
STATIONS. : Temperature. Point Temperature, Point
of De- —— —_tiof De- 1, Height

Barometer.} Air. | Merc. |position|Barometer. | Air. | ere position] Deduced.
1

Jardim di Serra, floor bnches: 2 % 2 mney © . arch

Mlthenrnerston et 127,651 49| 49 |41.5 [30.603 | 65. | 65 2782.6
Basin of the Spring 126.012] 46] 46 | 34 [30.543 | 65.5) 65.5 4453.9
Ridge ag the foot of the $125,948 |42|/42 | 36 |30.423|64 | 64 4379.7

Summit of the Pieo

Ruivo, The obser-

vations were made

eleven feet below the $124.938 36 | 36.5] 36 30.423 | 61.5] 61.5
summit, but th

computed height is

that of the summit

itHOLE ea asievewae sees

5438.1

The results have been deduced in the manner explained in
Mr. Daniell’s paper, ‘‘ On the Corrections to be applied in Ba-
rometric Measuration,” published in No. XXV. of the Quar-
terly Journal of the Royal Institution ; the barometric differences
have, been augmented by {zth, as 68 inches of mercury in the
tube are equivalent to one inch in the cistern ; and =, of the
approximate result has been added, as a correction due to the
variation in density of the atmosphere, in the latitude of
Madeira.”

Art. XII. Analysis of a New Sulphur Spring at Har-
rogate, by Wituiam West, Esq.
{Communicated by the Author.]

Aw exact acquaintance with the composition of the water of
mineral springs is, in many respects, highly important; with-
out it we can scarcely derive the full benefit from their medi-
cinal employment; it throws light on geology, and on the
chemistry of nature, and may hereafter furnish us with hints
for the improvement of various processes in the Arts.

Mr. West on a new Sulphur Spring at Harrogate. 83

Indeed, that the truth of this remark is generally felt by the
chemist and the physician is obvious, from the pains which
have been bestowed upon the improvement of the means for their
analysis, as well as the examination of the water of particular
springs. That in neither of these respects, however, have we
attained the requisite degree of certainty, is evident from the
fact that, in comparing two sets of experiments on any mineral
water, made by different persons, we find, in all cases, a con-
siderable difference in the results. If it be said, that this arises
from the water of the same spring being differently impregnated
at different times, I reply, that it sufficiently proves our present
deficiency, and should stimulate our diligence to observe that
we have no means of proving how far this is really the case,
or of distinguishing, with certainty, how much of the discre-
pancy so obvious between various reports of analyses is owing
to real differences in the water, how much to defective formule,
and how much to negligence or mistake in their application.
Probably on this, as well as on many other subjects, we have
begun to generalize too soon; theories of the origin of mineral
springs, and of their effect in the cure of disease, have been
more abundant than the facts ascertained respecting them would
warrant; the stock of careful analyses must be augmented be-
fore those theories can be either confirmed, or satisfactorily
disproved.

It is with this view that I am induced to make public the fol-
lowing analyses: the results which I obtained in the case which
admits of comparison with others, differ materially from their
statements; the account which I have given of the means used
will enable the reader to form some idea of their probable cor-
rectness.

The water of the Old Sulphur Well, at Harrogate, is of un-
doubted and extensive efficacy in a variety of complaints: with
a view to secure for general benefit the enjoyment of its advan-
tages, it is provided, by act of parliament, that the well shall
remain unenclosed, and it accordingly remains, covered only by
a cupola, open on all sides, and supported by very rude pillars.
This, while it secures the intended object of admitting all who

G 2

84 Mr. West on a

come to the free use of the water, is attended with very serious
inconveniences, such as the impossibility of excluding improper
persons, and the occasional occurrence of accidental or mis-
chievous impurities. To guard against these, as well as to
secure a more ample supply, various attempts have been made
to obtain a water of the same description, in other spots in the
neighbourhood; none of these have been perfectly successful,
until lately, when a well (the fourth dug there), has been dis-
covered in the grounds of Joseph Thackwray, at the Crown
Inn; this furnishes a water more highly impregnated, but which
is said to sit more easily on the stomach.

To analyze this water was the object of my journey to Harro-
gate. I was induced, for the sake of comparison, to examine
again the water of the Old Well.

Analysis of Water from the New Well at Harrogate.

The water, when fresh pumped up, is perfectly transparent,
and very sparkling; the temperature was 43.5°., that of
standing water, exposed to the air, being 37°.

The smell is powerfully sulphureous, the taste sulphuretted,
and strongly saline—a mixture of flavours, however, to which
the palate soon becomes accustomed, and which even appear
to reconcile each other. On standing it becomes turbid and
opalescent.

When boiled in an earthen vessel it loses its smell almost en-
tirely, and the surface is covered with small crystals. It dis-
colours and corrodes metallic vessels.

The specific gravity of the water is 1.01216 at 49°. equiva-
lent to 1.0128 at 60°. This would indicate, by Kirwan’s for-
mula, 198.5 of solid matter in each quart.

The quantity obtained by evaporation from a quart was, in
three trials, 211 grains.

The water restored the colour of litmus paper slightly reddened.

With nitrate of silver it produced an abundant dense preci-
pitate, of a deep brown colour, and a highly iridescent pellicle.

With sulphate of silver, an olive brown precipitate.

With muriate, nitrate, and acetate of barytes, no change takes
place; the water remains perfectly bright.

new Sulphur Spring at Harrogate. 85

Oxalate of ammonia; abundant precipitate.

Tincture of galls

Ferrocyanate of potash } No change.

Sulphocyanic acid

Carbonate of potash; a precipitate.

Lime water; a precipitate.

Barytes water; slight precipitate.

Acetate of lead; very copious precipitate, of a dark
brown colour.

The precipitated carbonate of lead becomes quite black
when diffused through the recent water.

Tincture of soap; an abundant curd.

Carbonate of ammonia caused no precipitate, nor did phos-
phate of soda; but, on applying these tests in succession to the
same portion of water, a considerable precipitate took place.

By these tests it is shewn, that the water examined contains
sulphuretted hydrogen and carbonic acid gases, muriatic acid
in combination with lime, magnesia, and an alkali; no sulphu-
ric acid, mo iron.

A wine pint of the water, previously boiled and filtered,
yielded, when treated with nitrate of silver, a white precipitate,
which, when washed with distilled water and dried, weighed
229.4 grains.

The crystalline pellicle, which separated from a quart on
boiling, weighed 2.2 grains ; it entirely dissolved in acetic acid.

One quart of the recent water was boiled with subcarbonate
of soda; the precipitate, (22.7 gr.) well washed, and treated
with sulphuric acid. On digesting the sulphates in a few
drachms of water and again drying, the sulphate of lime re-
maining weighed, after ignition, 18.7 grs., equivalent to 7.7
lime, or 17.85 muriate of lime.

The sulphate of magnesia, when evaporated and dried at a
heat approaching to redness, weighed 11.3 grains, equivalent
to 3.75 magnesia, or 10.75 muriate of magnesia.

The mixture of salts (211 grains) was digested in alcohol, to
separate the earthy muriates; what remained was muriate of
soda.

86 Mr. West on a

To separate the gaseous contents of the water, 56 cubic
inches were boiled until the quantity of gas received ceased to
increase; it measured 7.95 cubic inches. This was repeated
several times, and with larger quantities ; nearly the same pro-
portion was obtained.

When the whole of the gas was separated from a portion of
the water, a cubic inch tube, graduated into 100ths, was filled
and transferred to a bottle, containing precipitated carbonate
of lead; on agitating, under water, an absorption took place,
amounting to .50 of the gas operated on.

The residual gas was treated in the same manner with li-
quid potash, the absorption was .16 of a cubic inch.

That portion which resisted the action of carbonate of lead
and solution of potash (.34. C. I.), was transferred to a de-
tonating tube, with twice its bulk of oxygen gas, and fired by
the electric spark ; after this, the quantity absorbed by further
exposure to potash, was .14 of a cubic inch, leaving .20, which
I consider as azote.

It appears, then, that one gallon of the water in question con-

tains, of
Sulphuretted hydrogen . 6. 4 Cubic Inches.
Carbonic acid d . 5 25
Azote’. : CHORTO

Carburetted hydrogen . 4. 65

_—

32. 8.
Which are given out in the gaseous form on boiling; also of
Muriatic acid. . 458. 8
Soda. 5; ‘ 345. 2
Lime : ‘ : 34, 8
Magnesia. - dat 70
Carbonic acid. 3 4. 0
Existing in the water as

Muriate of soda . . 735. 0
Muriate of lime. aay #5)
Muriate of magnesia . 43. 0

Bicarbonate of soda . 14. 75

new Sulphur Spring at Harrogate. 87

The results of the same means, applied to the water of the Old
Well, were—of gases in one gallon,
Sulphuretted hydrogen . 14. 0 Cubic Inches.

Carbonic acid. : 4, 25
Azote . 4 : 1 BY
Carburetted hydrogen. 4. 15
30.4
Of solid contents.
Muriate of soda _ . ioe. 0
- lime. : Colo
— - magnesia . 29. 2
Bicarbonate of soda SWI eS

Specific gravity at 60°. 1.01324
Saline matter, by direct evaporation, 854.0

The most careful examination with tests, prepared by differ-
ent chemists, discovered not the least trace of sulphuric acid,
or sulphates.

On adding to equal portions of water from the Old, and that
from the New Well, an equal quantity of either acetate or car-
bonate of lead, the eye could distinguish a difference in the
colour produced, that from the New Well being a shade deeper
than that from the Old.

The most remarkable difference which will be observed be-
tween the present and former statements respecting the Old
Well (so far as the nature of its contents is concerned), is the
total absence of sulphuric acid in any combination. I was so
surprised to find this, that I hesitated to admit the inference
from my first trials; but with the salts of barytes, prepared by
other chemists, as well as with my own, not the slightest cloud
was produced.

Should the observations of any future chemist agree with mine
on this point, we must suppose, considering the respectability
of those who state the existence of sulphates in the water of the
Old Well (Drs. Scudamore and Garnett), this to be an esta-
blished case of a mineral water varying so much, as at times to
exhibit a notable quantity of a substance, at other periods wholly
absent.

88 Mr. West on a

I apprehend no difference in medicinal power need be appre-
hended from the subtraction of one grain in the pint, of a neu-
tral sulphate, whatever be its base, when supplied by a corre-
sponding quantity of muriate.

It seems, of itself, almost a convincing proof of the identity of
the general contents of the Old and the New Well, and of the
stratum whence they are derived, that at the period when the
latter was first examined, when no sulphuric acid could be de-
tected, it was wholly wanting in the former, in which, on pre-
vious occasions, it had been found.

1 come now to consider the gaseous contents of these waters;
these agree in their nature, and nearly so in their total quan-
tity, with those found by other chemists. Dr. Garnett found
19 cubic inches of sulphuretted hydrogen in the gallon, the
greatest quantity which I obtained, even when large bubbles of
gas were rising through the water in the well, was under 17
inches. Dr. Scudamore found it in the Old Well about 14
inches; the difference is not too great to impute to irregu-
larities in the production or absorption of the gas at the spring.

The proportion of carbonic acid, found by me, differs much
from the statement of Dr. Garnett, and still more from that of
Dr. Scudamore. I may observe, that in about a dozen trials,
the proportion was almost constant. On this point, I think
some error must have crept into Dr. Scudamore’s observations.
He deduced the quantities of the absorbable gases from the
weight of precipitate formed—a method which I tried, and
found very uncertain, and which must obviously be so, since
a loss or an increase of weight of one tenth of a grain in the
quantity which he employed, would give rise to an error of an’
inch and one-third in the calculation for one gallon. Dr. Scuda-
more no where informs us, in a direct way, what was the total
quantity of gas obtained from a gallon of the water, and the
statement in p. 98 of his Treatise, 29.045, cannot possibly be
the result of the experiments he has described, since none of
the numbers agree with those obtained by calculation from his
data; the proportion of unabsorbable gases, indeed, is but
@bout two-thirds of that stated in p. 97.

new Sulphur Spring at Harrogate. 89

The eudiometrical method which I pursued is short, easy
and susceptible to great precision; an error in the carbonic
acid, of one division of the tube, would scarcely affect .05 of a
cubic inch, the quantity in a gallon.

The carburetted hydrogen, not being known to be medicinal,
is of little consequence in that point of view; yet its presence
in these waters is a curious circumstance, the discovery of
which belongs wholly to Dr. Scudamore or his companion.
My experiments fix the proportion nearly as given by them, al-
though it seems quite unaccountable how they could arrive at it
by theirs *.

To sum up the comparison between the water from the Old
Well and that from Mr. Thackwray’s pump,—it appears that
both contain the same ingredients, solid and gaseous; that the
New Well has rather the greatest impregnation of the gases;
that the Old Well contains rather more common salt; while the
water of the New Pump holds a considerably greater propor-
tion of the active constituents, the muriate of lime and of
magnesia.

The experiments, which occupied several days, were per-
formed upon the spot; many were repeated several times, and
through the greater part, I had the benefit of the able assistance
of Dr. Murray, of Knaresbro’.

Leeds, Feb. 27, 1823.

* Carburetted hydrogen gas requires for combustion twice its volume of
oxygen, (Sir H. Davy’s Elements, p. 306,) instead of its own bulk, as these
experiments imply, and yields its own bulk of carbonic acid, instead of
one-third. How were such improbable results obtained ?

90 Mr. Davies Gilbert on the

Art. XIII. On the Vibrations of Heavy Bodies in Cycloidal
and in Circular Arches, as compared with their Descents
through free Space ; including an Estimate of the Varia-
ble Circular Excess in Vibrations continually decreasing.
By Davies Gitzert, Esq., F.R.S. &c. &c. Xe.

To the Ev1tor of the Quarterly Journal of Science and the Arts.
Dear Sir,

I am really not able to determine in what degree the follow-
ing investigations may be thought worthy of attention. They
were made about twenty years ago, and the impression left by
them on my mind mainly contributed to my subsequently mov-
ing the House of Commons, on the 15th of March, 1816, for an
Address to His Majesty, praying that directions might be given
for determining the length of the Pendulum; which has led to
all the important theoretical and practical discoveries of Capt.
Kater, and to the highly interesting observations of Captain
Sabine, and of others: on this account, at least, I may be ex-
cused for laying them before the public.

They exhibit a curious integration, by which a very simple
result, conformable to that of Euler, is derived from a great
apparent complexity.

The correction for variable circular excess in a free pen-
dulum, beginning its vibrations from an are comparatively
large, and ending with one very small, differs from those already
given by mathematicians; but the deductions seem to rest on
solid principles.

The whole possesses one quality throughout, which, in my
opinion, has not been sufficiently regarded ; and that is, a strict
preservation of the Harmonia MensuraRum.

I have constantly used the words Fluxion and Fluent, not-
withstanding that I am fully satisfied with the acknowledged
superiority of the new method over the old ; and that the deve-
lopement of functions is far preferable, as a general principle,
to considerations of motion; but there appear to me no
stronger reasons for changing established expressions, or no-
tations, on that account; than might be supposed to exist for

Vibrations of Heavy Bodies. 91

abandoning the term Calculation, because pebbles are no longer
used in the operations of arithmetic.

It may be proper for me to observe, that circular excess Is
not neticed by Sir Isaac Newroy, in the sixth section of the
second book of the Principia, treating De Motu et Resistentia
Corporum Funipendulorum.

And I may add that neither the resistance of media, nor
friction have any power to change the isochronism of an whole
vibration, so long as these retarding causes continue so smal],in
comparison with the action of gravity, as to render their second
powers insensible; since the lengthened time of descent will
be exactly compensated by the diminished time of ascent.

But the specific gravities of media affect both parts of a
vibration in the same way.

Let G = the specific gravity of the pendulum.

g = that of the medium, then & the loss of weight;

and since the times are inversely as the square roots of the

weight, the analogy will be as ene V1 ae
in Ve G
1 ;
— = (when % is very small) tol] + —L.
(when a is very ) to te

JL
G

Suppose the pendulum made of brass with a specific gravity
8.4, and that it vibrates in air the specific gravity of which, at a

: then will-9—, =: .—-'-_,,and) this amultiplied

mean, Is :
828 2G 13910

by 86400, the number of seconds in 24», will give a differ
ence of 6”.2 between vibrations in a vacuum, and in air at the

ordinary state of the atmosphere; or =aths of a second. for

each yariation of an inch in the barometer; a quantity, as it
would seem, not to be neglected in the present highly-advanced
state of practical astronomy, whenever confidence is placed
for any considerable interval, in the steadiness of the clock ;
and which, if it were carefully applied, would probably be

92 Mr. Davies Gilbert on the

founda to diminish considerably, the apparent irregularities in
the motion of our best time-pieces.

A variation in temperature of about 16° of Fahr. thermo-
16
480
one inch of the barometer ; but in the opposite direction from
expansion : this, however, is obviously included as a part, in the

general compensation for heat and cold.

Such as these investigations may prove to be, I place them
in your hands; and it will be highly gratifying to me if I am
allowed to see them honoured by a place in your Journal.

meter a ait) would produce an equal change with

Ist. The Descent through Free Space. Fig. I.
Let the line AB = 2, represent the height through which a
body is supposed to fall,
T = the time.

When the part 2 remains to be described, the velocity will

—1
2

be 2—2° . consequently 2—2? x T = —a or T=2-2
x—-z2T=2 .2—x? when x = 2 the equation vanishes,
when z = 0 T = 2,/2.

2d. The Semi-vibration in the Are of a Cycloid. Fig. II.

Let CP the length of the pendulum = 4, applying itself to
cycloidal cheeks CA and CB.

Let the diameter of the generating circle DP be = 2.

Let a = the length of the chord in the generating circle, cor-
responding with the cycloidal Are Pp, through which the pen-
dulum is supposed to vibrate; 2 = the length of the chord in
the generating circle corresponding with the Arc Px remaining
to be described. ;

Then will the velocity at the point * = aP—bP?= a@ — 22

2
And, the cycloidal Arc being double to the chord of gm

rating circle, q

Sw BA ‘ : —— 2 f
a-2a@ y~ T= —2¢ oroT=—2J/2xa— 2 x —@
w

Vibrations of Heavy Bodies. 93

T = 2,2 x cireular Are to radius unity and cos. , el
a
When x = a the equation vanishes
When «;=~Q

T = 2,/2 xX quadrantial Arc to radius unity.

3d. The Semi-vibration in the Arc of a Circle. Fig. III.

Let CP the length of the pendulum = 4, and from C with
CP as a radius, describe the vibratory circle.

Let C, as before, be the centre of a cycloid, and DP = 2.
The diameter of the generating circle.

a = the length of the chord in the generating circle, cor-
responding with the Arc Pp in the vibratory circle, through

which the pendulum is supposed to descend.
x = the length of the chord in the generating circle corre-
sponding with the Arc Px remaining to be described.
x

Then will the velocity of the point 7 = aP—4P =

=
a? — x2?

as before.

To find the fluxion of the space in relation to — @.
The absciss Pb in the generative circle corresponding to the

chord Pz will be a

But this absciss being common to both circles, the ordinate bx

2
in the vibrating circle willbe _/g _ % x Ss =o.
2

1 — 2

16

While z the chord in the generative circle diminishes by — a
the decrement of the abscis common to os circles will be — xa#
radius

“ordinate wae ae SV AET. ae

ratory circle, will give — 27 x ————_________. a —

be:

and this multiplied by —————_ aoe OF the vi-

94 Mr. Gilbert on the Vibrations of Heavy Bodies.

a! the fluxion of the space, which, divided by the ve-
a2
Lp

16

|b

Q¢ . a? — 72

16

Let the first part of this expression be expanded into series,
substituting 6 . for 16, then

locity gives T =

T=2/2x los Eda Fa Y'. 3x*z
Jat—az2 2b. fa®—a® 84... a®— 2*
5 rf 578 "7
152° . x itedak 2 vi” ‘Ke, )

48b3 Ve — 2 384b+,/ a— 2°

kk Satins i's de ss facets en 4 yer

PREY Laon ie) PA RR REARS C24

‘ Mey) Sh os
cer f a
i ‘
4 ayia My (?
yi
« f ;
i ” ry 4
oN, FN Fe ’ i hi i
° Tt a ye ema er ik f.
Me :
3 , a 7 . Ps
ae i
; ———— eee
fe eee et
4 Bief
‘ aly Pr :
; LA
ee © v . ts
4 iS fis
: ij " : 7
woe ;
‘ .
: -
, ‘ y
i

NOTED Ct . , |
‘ata’ Lae $o GON) no Ae

¥ area ote ‘.
"io i aaa anaes %

2

’

ait, Are Ye cvs,

1 )
1 = — &
J J s J 48)5. Er. 8 ‘ a
if = circular A udius unity & «
‘ \
> 1 ) 1 = > atu
[- Be Vane - [——
« Nv « ~ly v “
| —_ = cir. Are to cos
5 7
> 3 2 1 r
/ = a ff = are uae a
‘ Sb?,/ a*— a} 4 fa = 4 229
J 1 —
— ¢ ++ c ‘0 COS
= , =a ql, — cir. Arc t
2 5 15 td — J — — os
(- DE es TS - saty (=
‘ 5 N « 4 ‘ Oy
es
- x {= cir. Are. to cos. 2
if 10 105 f 79er137—§ a 7 1
‘ Sh bt J 540% J Sy , rt 8S J air! 4 —2 8
7 fc a a 5 1 - — ———— at x
= + x a yt A c to cos, —
; /——==-_y = + ——( ~V Saye ( — fas —cir. Arct =)
J i 2
And
T = 2,/2 x circular Arc to radius Unity and cos
( 1 Pat
x Y x fae—a +
1 SS 3 — 3
((— 29 x fata? + = xox J@—at + Sat x cir. Are to cos. +)
4 8 8 ¢
eS a 8 15 4 15 t
( z J a? - + — x = 4 7 + a x cir. Arc to cos. — )
6 24 48 18 a
105 1 35 5 Se 105
“ (ae foe + 2a yas y ie ee 4 105 gor % far— a? + 10 a8 x cir. Arc to cos, =
384 s 45 192 384 354 a
&e
Or
T = 2/2 x circular Are to radius Unity and cos, *
1 \
+ =a x cir. Are to cos. = )
» x Ve—@ + Sat x cir, Are to cos. 2)
8 a
15 1 ne see ha 15
x x ( es gt se atx X Va? — x + —a® x cir. Arc to cos,
48 b 6 9 18 48
105 es 7 oF ; 705 105
~- (= ot 4 7 gt. 254 35 gs LO EX > a® x cir. Arc to cos, =
384b* S s 192 354 7 a
Ke Ke &e Ke Ke

When x = 0 all the terms vanish

r = a (giving the whole semiyibration) all the terms vanish exc

And T=2y2x (1+ 4) °.2 4 =) pera )

“He 48

When it may be observed that the different numerical coefficients are the squares of these arising from the expansion of a binomial to the

pate
2

Mr. Gilbert on the Vibrations of Heavy Bodies. 97

In the case of a mercurial pendulum, these quantities must be
reduced to three-fifths (.6) of their magnitudes in the table.

It is then ascertained ‘

That the time of free descent down a given line,

The time of descent down the whole or any part of a cycloi-
dical are of the same height by the semi-vibration of pendulum
having a suspension twice as long ;

And the time of a semi-vibration by the same pendulum in a
circular arc, will be, in the proportions to each other of

Unity,
Unity x quadrantial arc,
Unity x quadrantial are x (1 + a - + 8 +

152 a? , 1052 a’
48 63 3854 64

Or substituting for a, the chord of semi-vibration in the vi-

&e. &c.)

bratory circle, which is in magnitude double to a, but in refer-
ence to its own radius taken as unity, will be one half of a, and
writing its values for 6 ; ia series Ladin

1 ) 2 ¢2 = a 2¢6 105 \2 c®
ee CY Q4 +2 po * aga.) geke.
If s the sine of a the are of semivibration be substituted,

the series becomes
3 \2 15 105 \2
1 =H yh s2 4° 3 )%ss a * 96 s& &e.
“4 8 48 ary “384.
or if » = the verse sine, the series becomes
1 3 \2 v2 Lan 2012 105 \2 v#
i+ i es ae bn) Reiwepaad Bo pigtts
2 3) a2 * a) as * aaa ) ga Be.
Thus far the investigations are strictly correct; but for all
practical cases of vibration in small ares, the two first terms of
the series need alone be regarded, and the second only in its
2 gt
first power, since the third term & S does not amount
to one second in 24 hours till the arc of semi-vibration reaches
10° 5’ ;nor the square of the second term till the are is 13° 24’.

98 Mr. Davies Gilbert on the

Moreover, the chord and are in the vibrating circle may be
taken as equal; for the arc in terms of the chord being z =

1 igre ese ere? 1.3.5 es
+ — — — —— X — — —- —-— Ke.
2 one” 2.4 5 2° 2.4.6 a TQ" -
when c is the chord of 9°2 the second term will be : very
10000

nearly, and consequently the cycloidal arc, equal to the chord of
the circle, will blend itself with circular arc.

The circular excess may therefore be taken in terms of the
chord of the arc of semi-vibration, of the sine of one half this
arc, and of its verse sine.

— v
which last corresponds with the expression given by Euler.

When a free or detached pendulum vibrates, the are must
continually diminish, and with it the circular excess. To ascer-
tain the amount of this quantity, which may be termed the
variable circular excess, from the incipient and final arcs,
together with the elapsed time ; it is obvious that the law govern-
ing the rate of decrement in the arcs must previously be known.
Two causes contribute towards producing this diminution of
the arc, resistance of the medium, in which the pendulum
moves; and friction on its axis of suspension. These must
be considered separately; and in doing so, it is perfectly ob-
vious that the minute differenee between cycloidical and cir-
cular vibrations in small arcs, cannot produce any sensible
effect on the rate of decrement; so that whatever law is esta-
blished in regard to the cycloid, it may, without error, be ex-
tended to the circle, where no change takes place, in the centre
of oscillation, during the semi-vibration, when a ball of finite
magnitude is used, as would be the case in a cycloid.

First, with respect to the resistance of the medium considered

Vibrations of Heavy Bodies. 99
as the only retarding cause. This must, according to every
theoretical principle, be taken to vary as the squares of the
velocities. Then in passing through any small space z, the di-
minution of velocity (¢) will be proportionate to v2 the square

of the velocity, and to ¢ the time, but

t= 2 «9 = v2 x Z = vz 0r to the space multiplied by
v v
the velocity of movement through it.
1
: : : PS
Now, as before in fig. 2d, the velocity at = will be & — 2°

S 2

And consequently this multiplied by — 2a will be = — 9

By expanding a2 — a and changing the signs

: 1 2 La 2. £6 :
= f2x Iie ee ee es and
Rp OS cope pay apg
1 1s 4x2 1 1 #5 3
=C re Se SE eI ef al Pe een Fe 2
? Py EK 2 3 az 8 5 at 48
7
Bega)
7 ae

1s) 1 Lae pl
then b Cc 2. (a — —; — 4 —) —.\=— 10% Ke:
en becomes C + 4/2. (a at a ewe )
oan! 2% pa |
= = 9 Ses) ree IQ? ee ee 2 &ec,
therefore C J/2 (a als a eure a )
When x = 0 the variable terms vanish, and the equation be-
| bey pro Liye!
= —-f/2¢ — —. —a? — =. =a? &e.
comes 9 A 2 saat ae oo )

The diminution of velocity is therefore proportionate to the
square of the are. And if » = the velocity due to any arc of
descent a, the actual velocity, when it is performed, will be
v — a? v. The ascent due to this velocity will be v2 — 2a2wv,
but the arcs being as the square root of the ascent, the arc due
to the velocity will be » — a? v; therefore the diminutions of

the arcs are proportionate to the squares of their length.
Vou. XV. H

100 Mr. Davies Gilbert on the

To determine the amount of circular excess in arcs con-
stantly diminishing from the effect of resistance, let a the larger
of two small arcs of descent which in any portion of time, con-
sidered as unity, diminishes to 6, ”

Let x = any portion of that time,

y = the arc of semivibration at that instant,

‘ais asuadalinibed se) = ume et
y

y° y
Whenz=0and y=a..C= Aue ae 1 ORs
a y a
And when «= 1 y = b, consequently 1 = ~ — a GR mb
r a
= am — bm, whence m = and x = alana? ae
a—b ay— by a? —ab
whence is derived
B55 ab
y= ———
a—bxat+b

y ab .

16 (a—b x « +6)*
expressed in terms of x and of known quantities. Then will
1 ab?

16 (a—b . x + 6)
excess of which the fluent is

And a y*, or the circular excess, will be

X a@ represent the fluxion of the variable

a—6b Roe Mack
Wheiz 0,0 = a'b

16 x a—b
The whole fluent, therefore,
a’b af a*b? 1

16 ee OME Sea ire 2 oe Oe
The fluent becomes
a*h — ab? ab

———— = — and this quantity multiplied by the number
16xa—b 16 ' , : P

of seconds observed between the two arcs of semi-vibration
a and 6, will give the whole circular excess in seconds.

Vibrations of Heavy Bodies. 101

In the next place, regarding friction as the sole retarding
power which is known to act simply in proportion to the time,
and without any reference to velocity.

It is obvious that while this is supposed to be extremely
small in comparison with the force of gravity, resolyed into
the direction of motion at the commencement of the descent,
and all increase of weight in the oscillating body arising from
centrifugal force, is disregarded, as being insensible ; that the
retardation of velocity in isochronous vibrations must be equal.

If this general deduction, however, admits of doubt, it may
be demonstrated in the following manner :

1
The velocity at x (Fig. 2d,) will be az,” consequently
/2
2.f2.a
a2— ret
uniformly retarding power of the friction, as compared with the
constant force of gravity be g, then will the fluxion of the re-

tardalavn be 2 a OP ORNS andat of which ie
ae — xr25

the time of passing through 22 will be

Let the

2.2.9 x Cir. Arc to radius unity and cos. ~
a

When « = a

= 2./2.g9 x quadrantial Arc to radius unity, which is
a constant quantity.

Since, then, the velocities are uniformly diminished, so will
be the arc of ascent due to such velocities, from what has been
already shewn: assuming therefore, as before, a, to be the in-
cipient semi-arc of free vibration, and 6 equal to the final semi-
arc, the time of passing from one to the other to be unity, x an
elapsed portion of that time, and y the corresponding arc of
semivibration with m a modulus,

r= my the fluent 2 =—my +c, when c=0 c=ma
The whole fluent, therefore, z=ma—my, when x=1 yb,
consequently 1 = ma — mb, or m Pe al whence
pe

H 2

102 Mr. Davies Gilbert on the

a=" _—_¥ and y =a — a—b. 2x, consequently, the
a—b a—b

fluxion of the variable circular excess os (a — a—b.x)?x a
the fluent of which is a (a2a2 —a xX a—b .2* + a—be 23)
when = 1] equal to a Ge which multiplied by

the number of seconds observed between the ares a and 3, will
give the whole circular excess in seconds.

And here it may be remarked that the expression
a’ x ab x B
1 he ea
tion, with that for measuring the frustum of a pyramid.

A formula involving both these causes would be extremely
complicated if, indeed, the fluent could be assigned in finite
terms. But it is probable that by carefully noticing the varia-
ble circular excess between two very small arcs, and between
two others comparatively large, some estimate may be formed
of the relative magnitudes of the retarding powers exerted by
friction, and by the resisting medium, unless the former should
really be found inappreciable in all practical cases.

corresponds, as it ought to do on the supposi-

A Taste for correcting the Time, as shewn by a clock, having
a brass weight, or ball, to its pendulum, for the variation of
one inch in the height of the barometer.

ARrGuMENTS.—The time elapsed since the last observation
of the barometer.

And the present observed height ~ 30 inches ao the: vari-
ation between the observations —

Additive, if the sum is Plus.
Subtractive, if it is Minus.

Vibrations of Heavy Bodies. 103

o

Le
2
me
4
5
6.
? eae
8
9.

104

Art. XIV. Proceedings of the Royal Society.

Tue following papers have been read at the table of the
Royal Society since our last Report :—

January 9, 1823.
Corrections applied to the great meridional arc, extending frons
latitude 8° 9! 38.39” N., to 18° 3’ 23.64! N., to reduce it to the Par-
liamentary standard, by Lieutenant-Colonel William Lambton.

At this meeting John Henry Vivian, Esq. was elected into

the Society.
January 16.

Some practical observations on the concentration and communieation
of magnetism, by Mr. J. H. Abraham.

January 23.
Observations on magnetism, by John Macdonald, A.M., F.R.S.

There was no meeting of the Society on Thursday, the 30th
of January, it being the anniversary of the martyrdom of
Charles f.

February 6.

Letter from Major-General Sir Thomas Brisbane, addressed to the
_ President, enclosing a paper by Mr. Charles Rumker, on the summer
solstice of IS22, observed at Paramatta.

Letter from Mr. Whidbey to John Barrow, Esq., accompanied with
drawings of the caverns found in the limestone quarries of Orestoa ;
also a description of the fossil bones found therein, by Mr. William

Clift.
February 13,

A letter from Dr. Young to the President, announcing the re-dis-
covery of Professor Encke’s triennial comet, by Mr, Charles Rumker,
the 2d of June last, at Paramatta.

At this meeting John Baron, M.D. of Gloucester, was elected

into the Society.
February 20.

Experiments for ascertaining the velocity of sound, made at Madras,
by John Goldingham, Esq.

Captain John Franklin, of the Royal Navy, was elected into
the Society at this meeting.

Proceedings of the Royal Soctety. 105

February 27.

On the question as to the evolution of heat during the coagulation of
blood, by Dr. Charles Scudamore.

On the double organs of generation of the lamprey, the conger eel,
the common eel, and the barnacle, which impregnate themselves ; and
of the earth-worms, the individuals of which tribe mutually impregnate
one another. By Sir Everard Home, Bart.

a

Arr. XV. Proceedings of the Horticultural Society.

Tuesday, January 7, 1823.

A Parer by the President, on the flat peach of China, was read. It
contains some curious particulars as to the habits of this very remark-
able plant, which was imported by the Society from China in 1820.
It appears to possess a degree of excitability exceeding any that can be
given, even temporarily, to any other variety of {peach. In 1821, its
blossoms unfolded in January in a peach-house, the lights of which
were all off, and the fruit set freely, with the protection of a mat only.
Last year it blossomed in November, before the lights of the house
were put on ; and on the 3d of January, when the paper was written,
the peaches were as large as peas, with no more heat than would just
exclude the frost. What is very remarkable in this plant is, that it
retains its old leaves in full vigour until after the new are put forth.

Several collections of pears and apples were exhibited ; among the
vegetables shown, were remarkably fine specimens of an early variety
of rhubarb, grown by Mr. William Buck, in the garden of the Hon.
Greville Howard, at Elford near Lichfield. - It is of a beautiful pink
colour, which it retains when cooked.

Tuesday, January 21.

A paper by James Robert Gowen, Esq., was read, descriptive of
a new beautiful hybrid amaryllis, raised by William Griffin, Exq., and
which had flowered in the stove at Highcelere.

A paper by David Powell, Esq., was read, communicated by Charles
Holford, Esq., on an easy method of securing the scion to the stock in
grafting.

‘Two papers, on the cultivation of the mushroom, were read, one by

106 Proceedings of the Horticultural Society.

James Warre, Esq., the other by Mr. William Hogan, gardener to
Mr. Warre. f

A paper, by Mr. Thomas Milne of Fulham, on the cultivation of the
English cranberry (vaccinium oxycocus,) in dry beds, was read.
Mr. Milne’s success in managing this very desirable fruit, which has
hitherto been considered incapable of cultivation, has been such as to
leave no doubt that it will soon become an inhabitant of our gardéns,

Various seeds and scions were distributed to the members
present, and numerous specimens of fruits were exhibited.

Tuesday, February 4.

His Majesty the King of Bavaria was elected a Fellow of the
Society.

The following papers were read :—

On the autumn and winter management of cauliflowers, so as to
preserve them through the winter. By Mr. George Cockburn, gar-
dener to William Stephen Poyntz, Esq.

On the cultivation and propagation of gardenia radicans. By
Mr. Samuel Sawyer, gardener to Isaac Lyon Goldsmid, Esq.

On the management of fig-trees in the open air. By Mr. Samuel
Sawyer.

Notes on the effects of frost upon glazing. By Joseph Sabine,
Esq., F.R.S., &c., Secretary.

On forcing strawberries. By Mr. George Meredew, gardener to
Charles Calvert, Esq.

Mr. Robert Clews, gardener to the Duke of Devonshire, at
Chiswick-house, exhibited various sorts of grapes in a state of
perfect freshness.

Many varieties of apples and pears were also shown, sent by
different members.

Tuesday, February 18. The following papers were read :—

On a method of treating potatoes, so as to preserve them in a fresh
state during the winter. By Mr. John Goss.

Proceedings of the Horticultural Society. 107

On a variety of brassica oleracea fimbriata, called Woburn peren-
nial. cabbage. By Mr. John Sinclair, gardener to his Grace the Duke
of Bedford, at Woburn.

On the fertilization of the female blossoms of filberts. By the Rev.
George Swayne. Mr. Swayne’s talents, as a careful experimentalist
in horticulture, are well known; and the present paper affords another
proof of the advantages which are to be derived from a combination of
philosophical inquiry with practical skill. Mr. Swayne suspected that
the infertility of the filbert was occasioned by the deficiency of male
blossoms ; and it occurred to him, that by obtaining branches of the
wild hazel, and suspending them over the filbert plants, he would com-
pensate for that deficiency. This experiment he tried with complete suc-
cess, and the paper gives an interesting detail of his mode of operating,

Tuesday, March 4.

A paper on the cultivation of melons in the open air, by John
Williams, Esq., was read.

A communication by the Rev. John Bransby, was read, stating
some useful particulars as to the best mode of cultivating the tetragonia
expansa, or New Zealand spinach.

A paper by Mr. John Lindley, the Assistant-Secretary at the gar-
den, was read, containing some particulars relative to the seedling
varieties of amaryllis, which had been raised by the Hon. and Rev.
William Herbert, and flowered in the garden of the society. Se-
veral of the varieties, in fine flower, were shewn at the meeting.

A large collection of fruits, preserved in spirits, were exhi-
bited; they were brought home by Mr. George Don, a bota-
nical collector in the service of the Society. They had been
collected at St. Thomas’s, Africa, Maranham, and Trinidad.

The silver medal of the Society was presented to Monsicur
Charles Mathurin Villet, of the Cape of Good Hope, for his
attention in sending a fine collection of bulbs and seeds to the
garden of the society.

108

Arr. XVI. ANALYSIS OF SCIENTIFIC BOOKS.

A Comparative Estimate of the Mineral and Mosaical
Geologies. By GRANVILLE PENN, Esq. 8vo. Pp. 460.
Ogle, Duncan & Co.

WE take shame to ourselves for having suffered this valuable
book to remain so long unnoticed on our shelves, or only inci-
dentally mentioned in some of our late reviews. At a period
like the present, when many of the disciples of modern geology
either boldly disclaim all belief in the Mosaical account of the
creation, or consider it at best as a mere allegory—or when
others, with a less daring but not less dangerous scepticism,
admit, with Moses, the broad self-evident truth, that God did,
at some time, and in some manner and form, call this world
into being by his own immediate act, but deny that the time
and mode are explicitly detailed in the sacred record he has
bequeathed us ;—when both allow, that since its first creation,
it has obviously undergone a violent revolution, but contend
that the history of the deluge is insufficient to account for it;—
and when a third party, professing its belief in the Mosaical
history, tampers with its details, or distorts them to any mean-
ing that may best suit some favourite hypothesis, extending
days into ages, multiplying revolutions, and, in short, giving
the sacred text any interpretation rather than the literal and
true one;—at such a period, we hail the appearance of the
“‘ Comparative Estimate,” with unfeigned satisfaction. To re-
lieve the mind of the anxious and sincere inquirer after truth
“‘from perplexity; to disengage it from error concerning the
important subject of which it treats ;” and to demonstrate the
essential connexion between moral and physical evidence, when
we endeavour to explain the causes of the present state of the
crust of the earth, by the sensible phenomena it presents to our
inspection, are the great objects of this treatise. In inquiring
how far this has been accomplished, we shall endeavour to give
our readers an impartial account of its contents; in doing which
we shall indulge very little in digression, and not at all in
speculation—convinced, with our author, that what we cannot
find within the limit of a true philosophical geology, “is not
permitted to the sphere of our real knowledge. To know that
we cannot know certain things, is in itself positive knowledge,
and a knowledge of the most safe and valuable nature; and to
abide by that cautionary knowledge, is infinitely more condu-
cive to our advancement in truth, than to exchange it for any
quality of conjecture or speculation.” We shall hold our
author’s ground sacred, to be trodden by no foot but his own—

Mineral and. Mosaical Geologies. 109

we shall abstain even from endeavouring to shew the relation
of facts, discovered since his work appeared, with the sound
geology he advocates. We shall leave the hyenas, in the cave
of Kirkdale, to feast on elephants, and pick their teeth with
rats-bones at their leisure; we shall not stop to ask, whether
the gnawings on the larger bones are as evident to the natural
eye as to the eye of the imagination, nor whether the propor-
tion of Album Gracum to the hundreds of teeth and bones
which, we are informed, were strewed over the mud at the bot-
tom of the cave, from one end to the other, “like a dog-kennel,”
was such as is usually found in dog-kennels of the present
day, or only what would necessarily be left after the
decomposition of the more destructible matter of dead car-
casses. It is not, however, that we conceive the explanation of
the phenomena of the Yorkshire cave to be amongst those
things which are not permitted to the sphere of our real know-
ledge, or that any serious difficulty attends their reconciliation
to our author’s geological interpretation of the sacred text; but
in pure deference to him, we forbear to meddle with a subject
which properly belongs only to himself. We shall, therefore,
wait in patience for the second edition of the ‘“* Comparative
Estimate,” in which, we are confident, our expectations will not
be disappointed.

The object of the work, as its title denotes, is to examine
and decide between the mineral and the Mosaical geologies, as
to their respective pretensions to guide us in our investigation
of the modes by which, and the times in which, the several
classes of mineral matter composing this earth received their
sensible formations.

The latter of these geologies is of very great antiquity, and rests its cre-
dit for the truth of the historical facts which it relates, upon a record pre-
tending to divine revelation, and acknowledged as such by the uninterrupted
assent of some of the best and wisest of mankind, for upwards of e
thousand years. The former is of very recent origin, and can hardly be
said to have existed in a state tats to maturity for more than half
acentury. It does not indeed pretend to oppose any record to that of the
other; but it aspires to establish a series of historical facts, by induction
from chemical principles newlydiscovered, which, it affirms, disclose evi-
dence of truth superior to any that is presented in the professedly historical
document, and which must, therefore, qualify the credit which that docu-
ment is entitled to receive,

It pretends that, by employing the method of analysis and
induction from ‘+ observation, sound principles of physics, and
the rules of an exact logic,” introduced by the happy revolution.
effected by Bacon and Newton in the studies of the natural
sciences, and by “adhering to the rules taught and practised
by those great teachers, it is able to reason from the sensible
phenomena of mineral matter, to the mode of its first forma-
tions and subsequent changes.” The Mineral Geology (under
which term our author includes the Wernerian and Huttonian,
as well as all other geological systems not founded on the

110 Analysis of Scientific Books.

Mosaical history) appeals, therefore, to the philosophy of Bacon
and Newton in proof of its own validity; and since the merits
of the two geologies can only be tried by applying both to some
common and agreed test, the Mosaical consents to submit itself
unconditionally to the same philosophy, and to leave to its ver-
dict the ultimate decision, which is true, and which false—
for so wholly contradictory are they to each other, “ that
whichever of them be true, the other must of necessity be ab-
solutely and fundamentally false.”

Before we proceed further, it is necessary to inform the
reader, that whenever our author asserts that such a statement
is made, or such a conclusion drawn by either of the con-
tending parties, he invariably supports his assertion by refer-
ence to some writer of established authority, and, in most cases,
quotes the passages referred to. Indeed nothing can be further
from chicanery or subterfuge, than the manner in which he
conducts his argument from beginning to end ; and the work
is not more remarkable for the closeness of its reasoning, and
the lucidus ordo that prevails throughout, than it is for the
spirit of upright honesty and manly candour which animates
every page of it. He thus proceeds:

The mineral geology concludes, from the crystalline phenomena of this
earth, that it was originally a confused mass of elemental principles, pe Saas
in a vast dissolution, a chaotic ocean, or original chaotic. fluid ; which, after an
unassignable series of ages, settled themselves at last into the order and
correspondence of parts which it now possesses, by a gradual process of
Brecipitston and crystallization, according to certain laws of matter,
which it denominates the laws of affinity of composition and aggrega-
tion, and that they thus formed successively, though remotely in time,

1. a chemical, 2. a mineral, and lastly, a geognostic, which is its present
structure.

Is this conformable to Newton on the same subject ?

It seems probable to me, (said the wise, sober, and circumspect
Newton,) that God in the beginning, formed matter in solid, massy, hard,
impenetrable, moveable Dana of such sizes and figures, and with
such other properties, and in such proportions to space, as most conduced
to the end for which he formed them. All material things seem to have
been composed of the hard and solid particles above-mentioned, variously
associated in the first creation, by the counsels of an intelligent agent.
For it became him who created them to set them in order, and if he did
so, it is unphilosophical to seek for any other origin of this world, or to pre-
tend that it might rise out of a chaos by the mere laws of nature; though,
being once formed, it may continue by those laws for many ages *.

So much for the first result of the application of the test.

The mineral geology has stated further, that ‘‘ during the

long process of crystallization and precipitation, and before it
attained to its present solidity, the earth acquired its peculiar
figure (that of an oblate spheroid) by the operation of the
physical laws which cause it to revolve on its axis.” This
Newton had observed to be the form of the planets ; and rea-
soning on the fact, he discovered that the “ rule of harmony

* Optics, L. iil, in fin.

Mineral and Mosaical Geologies. 111

and equilibrium” between the two antagonist powers of gravity
and centrifugal force can only be found in that figure. Hence
the mineral geology appeals to his philosophy in support of
its assertion, and concludes, “since the earth has that sphe-
roidal form which its motion of rotation ought to produce in a
liquid mass, it follows, necessarily, that it must have been
fluid.”

It does not follow necessarily, nor at all, nor is any such
consequence deducible from Newton’s philosophy. Newton,
with no other view than to illustrate his meaning, supposed an
earth formed of an uniformly yielding substance, in order to
shew that whilst at rest such a mass would be spherical, but
that when made to revolve on its axis, it would assume a sphe-
roidal form. But Newton constantly maintained “ that God
at the beginning formed all material things (and, therefore,
this earth which is one of them) of such figures and properties
as most conduced to the end for which he formed them,” and
consequently, for the reasons already given, ‘“ he formed the
earth with the same figure which, it is manifest, he has given
to the other planets. Moreover, unless the earth was actually
flatter at the poles than at the equator, the waters of the ocean
constantly rising towards the equator, must long since have
deluged ‘and overwhelmed the equatorial regions, and have
deserted the polar, whereas the waters are now retained in
equilibrium over all its surface.” Thus its oblate spheroidal
form is no proof of its original fluidity, though it is an incon-
testable one of that divine wisdom which fashioned it according
to the strictest rule of “‘ harmony and equilibrium” between
those laws which he had ordained it should for ever after be
obedient to, and which therefore *‘ most conduces to the end
for which he formed it.” ‘Thus, both from crystalline cha-
racter and from the obtuseness of spherical figure, the mineral
geology concludes to chaos; whereas from both of these
Newton concluded to God.’

Our author proceeds to shew that this discordance between
the conclusions of the mineral geology and those of Newton,
arises from the analysis of the former being limited to mineral
matter, whereas Newton’s included all matter, of which mineral
matter is only a part. The investigation of the mode of the
first formation of mineral matter must be connected with the
investigation of the mode of the first formation of all matter
in the general, otherwise we assume a partial principle for a
general, and setting out in error, must continue in it to the
end. ‘ Such a wonderful conformity in the planetary system,”
said Newton, “‘ must be the effect of choice, and so must the
uniformity in the bodies of animals; these and their instincts
can be the effect of nothing else than the wisdom and_ skill
of a powerful, ever-living agent.”

112 Analysis of Scientific Books.

With common sense and Newton, all first formations are
creations, and by that term he denoted them. Were it other-
wise, there would be formations before first formations, which
is absurd. Deluc would not use the term created, because,
said he, ‘‘ in physics, I ought not to employ expressions which
are not thoroughly understood between men.” Our author
reprobates his conduct and his argument with just severity.
“‘ Was he aware,” says Mr. Penn, “that in excluding the word,
he at the same time excluded the idea associated with that
word; and, together with the zdea, the principle involved in that
idea—the exclusion of which is the very parent cause of all
materialism and all atheism ?”

It was the all-sufficiency ascribed by the mineral geology to
physical impressions, or what it denominates phenomena, to
determine the great question of the mode of the first formation
of mineral substances, that induced it to check its analytical
progress, short of the end to which it ought to have pursued it.
Our author, therefore, proceeds to shew how insufficzent pheno-
mena alone are to determine that+question.

If a bone of the first created man now remained, and were mingled with
other bones, pertaining to a generated race; and if it were to be submitted to
the inspection and examination of an anatomist, what opinion and judg-
ment would its sensible phenomena suggest, respecting the mode of its first
formation, and what would be his conclusion? If he were unapprized of
its true origin, his mind would sce nothing in its sensible phenomena, but the
laws of its ossification ; just as the mineral geology ‘‘ sees nothing in the
details of the formation of minerals, but precipitations, crystallizations, and
dissolutions.” He would therefore naturally pronounce of this bone, as of
all other bones, that “its fibres were originally soft,” until, in the shelter
of the maternal womb, it acquired “ the hardness of a cartilage, and then
of bone ;” that this effect ‘ was not produced at once, or in a very short
time,” but by degrees ; “ that after birth, it increased in hardness, by the
continual addition of ossifying matter, until it ceased to Brew at all.”

Physically true as this reasoning would appear, it would nevertheless be
morally and really false ; because it concluded from mere sensible phenomena,
to the certainty of a fact which could not be established by the evidence of
sensible phenomena alone ; namely, the mode of the first formation of the
substance of created bone.

From hence we obtain a second principle, with respect to such first for-
mations by creation, that their sensible phenomena alone cannot determine
the mode of their formation, since the real mode was in direct contradiction
to the sensible indications of those phenomena.

The same ingenious argument is then applied to vegetable
first formations, and the just inference deduced from both—that,
from phenomena alone, physics can determine nothing “ con-
cerning the mode of the first formations of the first individuals
composing either the animal or vegetable kingdoms of matter.”

Nor are they “a whit more competent to dogmatize concerning
the mode of first formations, from the evidence of phenomena
alone, in the mineral kingdom, or to infer that it was more gra-
dual, or slower, than those of the other two. For,” continuing
the comparison, and transferring it to created mineral matter,
‘ the sensible phenomena which suggest crystallization to the

Mineral and Mosaical Geologies. 113

Wernerian, or vitrification to the Huttonian, in examining a
fragment of primitive rock, are exactly of the same authority,
but not of a particle more, with that which wouid have sug-
gested ossification and lignification to the anatomist and natu-
ralist, who should unknowingly have inspected or analyzed
created bone or created wood”—and all would be equally in
error, in concluding them to have been respectively formed by
the modes of crystallization, ossification, and lignification.
‘‘ The mineralogist can no more discover the mode of the for-
mation of primitive rock by the laws of general chemistry”—
“‘ than the anatomist can discover the mode of the formation of
created bone, by the laws of generation and accretion.”

Concluding, then, with Newton, that “God at the beginning
formed ail material things” of such “ figures and properties as
most conduced to the end for which he formed them, we per-
ceive that there must have been a first-fortied created man, as
certainly as there has since been a succession of generated
men ; and that it is most consistent with the notion of an intel-
ligent agent, and therefore most philosophical, to suppose that
he created that first man with the perfection of mind and body
which most conduced to the end for which he formed him”—
and the same argument is equally applicable to all other first
created animals, and every first created individual of the vege-
table kingdom. As, therefore, in two parts out of three of the
tripartite system of matter, we have ample ground to conclude,
“‘ That the first formations must have been produced in their
full perfection, perfect bone and. perfect wood,” we must infer,
from every principle of sound analogy, that in the third part,
‘‘ where the first formations were as essential to the structure
of the globe, as in the two former to the structure of their re-
spective systems, the first formations were likewise produced in
their full perfection, perfect rock—and we have seen that sen-
sible phenomena can have no authority whatever in this question.”

The fatuity of the analogies by which the mineral geology
attempts to support its darling chaos, and the absurdity of in-
ferring, from the slow progress of generated beings to matu-
rity, the slow progress of the earth from a state of confusion to
its present form, is next forcibly demonstrated, and Deluc’s
a about mountains and pyramids ridiculed as it deserves
to be.

Equally absurd is the attempt to find secondary causes for
first-formed, created things. Of this class are the speculations
concerning the agents by which the mineral geology supposes
primitive rocks to have been held in solution. To prove the
legitimate relation between cause and effect, either the cause
must be known in the course of actual operation, or the effect
in the course of actual production; and who ever knew a gra-
nite rock in course of actual production, or a menstruum ex-

J

‘
\

114 Analysis of Scientific Books.

hibiting a cause capable of producing it? Secondary causes
can only effect secondary productions. Created bone and
wood were not produced by secondary causes—“ yet we know
that there are secondary causes which produce bone and wood,
but we know of no secondary cause.that produces granite—and
the reason appears to be obvious; for the animal creation
(from the perishable nature of the individuals that compose it)
was to subsist by succession to the first-formed individuals,
and therefore laws for securing that succession were necessary :
but the mineral creation was to subsist permanently in its first-
formed individuals, therefore no laws for their multiplication
were necessary. And from this consideration alone accrues a
very powerful moral evidence, that the first mineral formations
which are still permanent, were formed by no other mode than
that” (viz. creation) “‘ which formed the jirst animals, which
have been succeeded by generation.”

The crystalline texture and hardness of granite rocks, whence
they derive their solidity and durability; their immense height,
to which is owing the accumulation of supplies for the rivers
which irrigate the globe, together with their lengthened and
inclined forms to determine the direction of those rivers, are
so many proofs of unchangeable arrangement which adapts
them ‘‘to the end for which they were formed’”’—and <‘‘ how is
it possible,” exclaims our author, ‘ to contemplate all this,
without rendering immediately to God the things which are
God’s?”

Having shewn, in the first part of the work, that the chaotic
principle of the mineral geology is incapable of standing the
test of the reformed philosophy of Newton, our author proceeds,
in the second part, to examine by the same test the pretensions
of the Mosaical Geology to explain the mode of the first for-
mation and the revolutions of this earth. From the philosophy
of Newton we attain the highest probabilities in regard to this
subject, and the Mosaical geology professes to add the consum-
mation of absolute certainty. But certainty as to past events
can only be derived from competent and positive history. Now,
the history which professes to account for the mode of the first
formations and revolutions of the earth, is that’ ‘‘ ‘ Revealed
History’ which was imparted to man by God, (the only possible
voucher for the facts of creation), through the ministry of
Moses ;” the authority of which record the judgments of Bacon
and Newton unequivocally and entirely acknowledged, and the
former grounded the foundation of his new philosophy on its
statements.

This sacred and inestimable record, which was revealed to mankind
above 3000 years ago, unfolds a detailed recital of the sensible mode by
which God “ formed and set in order” the entire system of this terrestrial
globe; and likewise the history of a great universal revolution, which he
caused it to sustain Ne the operation of water, 1656 years after he had
created it,—This record comprises the Mosaical Geology.

Mineral and Mosaical Geologies. 115

‘Our author then proceeds, in the first place, to shew, that
the interpretation of the Hebrew text in the first chapter of
‘Genesis, as it stands in our Bible, is not absolutely correct, and
to suggest the alterations which seem to him to be necessary,
and which he supports with great learning and critical acumen.
He adopts and defends the canons of interpretation laid down
by Rosenmuller, namely, ‘‘ That the style of the first chapter,
as of the whole book of Genesis, is strictly historical, and that
it betrays no vestige whatever of allegorical or figurative de-
scription.” That “since this history was adapted to the com-
prehension of the commonest capacity, Moses speaks according
to optical, not physical truth—that is, he describes the effects
of creation optically, or as they would have appeared to the
eye, without any assignment of physical causes.”

A circumstantial inquiry into the events of the six days of
creation, with occasional criticisms on the true interpretation of
the original Hebrew, occupies the remainder of the second part.
It would be impossible, within the limits of a review, to follow
the author through all the details of this important division of
his work. We must therefore refer our readers to the original
for the several minutie, and confine ourselyes to the general
outline, with such occasional quotations from the text, as the
importance of the subject, or justice to our author, may seem
to require.

“At the beginning,” says Newton, “and in one moment of
time,” says Bacon, the earth was created, entire and complete,
as to its form and texture, though enveloped with a marine
fluid, resting on and flowing over every part of its surface,
which formed for a very short time the bed of an universal sea.
The solid body was concealed by the cloak of waters, and total
darkness encompassed that cloak; God then commanded the
existence of light, and divided the light from the darkness—
“that is, he established and gave first operation to the laws of
proportion and succession between the measures of the two,
and having given origin and action to those laws, they accom-
plished in their due course the first day.

The apparent confusion between the command, “ Let there
be light,” delivered on the first day of creation, and the record
that God made two great lights, on the fourth day, which
has been a stumbling-block to many eminent writers, is thus
ingeniously cleared up by our author.

The light of which Moses speaks in the first day, “‘ proceeded
from the same solar fountain of light” that has always illumi-
nated this world, but ‘ ignorance on the one hand, and system
and hypothesis on the other, have variously contrived to per-
plex or pervert this simple recital.” The late Sir William
Herschel discovered that the body of the sun is an opaque sub-
stance, and that its light and heat proceed from a luminous

Vou. XV. I

116 Analysis of Scientific Books.

atmosphere attached to its surface. ‘So that the creation of
the sun as a part of ‘the host of heaven,’ does not necessarily
imply the creation of light, and conversely, the creation of light
does not necessarily imply the creation of the body of the sun.
In the first creation of ‘ the heaven and the earth,’ therefore,
not the planetary orbs only, but the solar orb itself, was created
in darkness, awaiting that light which by one simple divine
operation was to be communicated at once to all. When, then,
the almighty word, in commanding light, commanded the first
illumination of the solar atmosphere, its new light was imme-
diately caught and reflected throughout space, by all the mem-
bers of the planetary system. And well may we imagine, that,
in that first sudden and magnificent illumination of the universe,
‘The morning stars sang together, and the sons of God shouted
for joy!”

The body of the sun itself, however, or rather its luminous
atmosphere, was still concealed from the earth by the waters
on its surface, and the exhalations which the sun’s heat raised
from them. It was not till the fourth day, that the cause of
light was to be visibly revealed to the earth. But its effecis,
and the alternation of light and darkness, subsisted from the
first day, when “ both the solar fountain of light was opened in
the heavens, and the earth received its first impulse of rotation
on its axis, and in its orbit :” and consequently, “ time, which
only exists in reference to that revolution, began with the crea-
tion of the globe, and the commencement of its revolution in
darkness; and the creation of light succeeded at that proportion
of distance in time, which was thenceforth to constitute the per-
petual diurnal divisions of the two.”

The philosophy of Bacon and Newton is in perfect unison
with the sound learning and criticism of Rosenmuller, and
concurs with him in concluding, that the days of creation were
not, as the chaos of the mineral geology requires, indefinite
measures of time, but natural days—beginning from one even=
ing, and ending with the next; and he equally coincides with
those illustrious men in reprobating, in the strongest terms,
the preposterous inference of a chaos from the language of
Moses. :

The division of “‘ the waters from the waters,’’ by the firma-
ment, is explained to mean the separation of the watery vapours
from the waters covering the earth, by the creation and interpo-
sition of the aérial atmosphere; but this vapour, in the form of
congregated clouds, still prevented the sun itself from ‘being
visible.

The mode of the “ gathering together of the waters into one
place,” on the third day, forms a remarkable feature in our
author’s exposition of the sacred text. This he considers to

have been effected by a violent disruption and depression of

ea

Mineral and Mosaical Geologies. 117

the solid parts, which were to be deepened, in order to form
the bed of the sea, into which the waters were now to be col-
jected. ‘The solid ‘ framework or skeleton of the globe’ was
‘therefore burst, fractured, and subverted, in all those places
where depression was to produce the profundity ; and it carried
down with it, in apparent confusion, vast and extensive portions
of the materials which had been regularly deposited or com-
pacted upon it, leaving other portions partially dislocated and
variously distorted from their primitive positions. So that the
order of the materials of the globe, which, in the reserved,
unaltered, and exposed portion, retained their first positions
and arrangement, was broken, displaced, and apparently con-
founded in the other portion, which was to receive within it
the accumulated waters.”

On the same day, the newly-exposed portion was, by the
immediate creative act of God, covered with the maturity of
vegetation—“ the herb yielding seed, and the tree yielding fruit,”
each after its kind, in complete and instantaneous perfection.
On the fourth day, the clouds were dispelled and the sun be-
came visible in the heavens, “ in the full manifestation of its
effulgence.” The moon also became visible on this day, that
is, on the third evening of the earth’s revolution, according to
common computation, which answers to the fourth evening of
the Mosaical day, or Nycthemeron. ‘Thus the Creator re-
served the exposure of his heavenly calendar, for the day when
the planet which, by his own laws, was to rule the night, had
acquired by those same laws the position which first enabled it
to display its domination.”” Whence we infer, that at the mo-
ment of their creation on the first day, the sun and moon “ were
in that particular relation to the earth, which astronomy calls
inferior conjunction, and that in its diurnal revolution they first
acquired, by their separation, that relative aspect which quali-
fied them to be manifested together, as the two great indices of
annual and menstrual time, but for which manifestation, both
would not have been prepared on an earlier day.” Thus the
first day of creation was the first day of the first solar year;
and the first day of the first lunar month; and, as we learn
afterwards, by the sanctification of the seventh day, the first
day of the first week ; and “it is sufficiently manifest, from the
concurring authorities of learning and philosophy, that the solar
light which, upon the fourth day of creation, was transmitted
immediately and optically from the solar orb, was the same
light that, during the three preceding days, had been transmit-
ted through a nebulous medium, interposed between it and the
earth,”

But we must forbear to travel thus, step by step, with our
author; and, painful as the exertion is to quit even for a short
time so delightful a companion, we must leave him to comment

12

118 Analysis of Scientific Books.

alone on'the great events which yet remained to be accom-
plished in the fifth and sixth days, namely, the creation of the
animal kingdom, “ closing full in man,” each individual in
full maturity and perfection, by the immediate and instantaneous
act of God; and to shew, in the concluding chapter of this
part, how positively the philosophy of Bacon and Newton de-
cides the first great question, the mode of first formations, in
favour of the Mosaical geology. One important fact, however,
we must remind the reader to keep in his recollection, viz., the
‘structure of the bed of that ocean, on whose ruptured slimy
bottom were now deposited, in abundance, marine matter of
every kind, vegetable and animal, and which continued to in-
crease, in a multiple ratio, during a period of more than sixteen
centuries.

Our author, in the third part, proceeds to examine the second
great question, the mode of the universal changes or revolutions
which the mineral substance of the earth has undergone since
the creation, and whether the evidences of revolution which it
reveals, correspond with the statements of the sacred record,
and are sufficiently accounted for by it; or ‘‘ whether the mi-
neral geology has found evidences of revolution not reducible
to those stated in the record.”

God having determined, in consequence of the wickedness of
the human race, to destroy both it and the earth, suspended for
a time the order of things which he had established, and again
assumed an immediate operation in the works of his terrestial
creation; ‘ All the fountains of the great deep were broken
up, and the windows of heaven were opened.” But, after the
deluge had accomplished its work of destruction, and the
Almighty was pleased to withdraw the waters a second time
from the surface of the earth, ‘‘ what was that second earth
upon which the ark was brought to rest, and whence did it
derive its origin?”

We cannot fail to perceive that a repetition of the same process which
produced the former earth was alone requisite to bring to light another
earth to replace it. We have already seen that a violent disruption and
subsidence of the solid surface of one portion of the subaqueous globe pro-
duced at first a bed to receive the diffusive waters ; and that these waters
drawn into that bed from off the other portion of the same globe, left it
exposed and fitted for the reception of vegetation, and for the habitation
ofman. That exposed portion was now in its turn to sink and disappear.
By a similar disruption and subsidence of its surface, which should depress
it below the level of the first depressed part or basin of the sea, the waters
flowing into a still lower level, would leave their basin empty, exposed and
dry, and thus by a similar separation render it in its turn a habitable earth :
—thus that first depressed part or basin of the former sea is our actual
present earth.

This idea, we believe, is peculiar to our author, who, with
great depth of learning and argument, contends that the de-
struction of the former earth was not temporary and confined
to the surface, but final and entire. The most strenuous advo-
cate for the mineral geology cannot deny that the conclusion

Mineral and Mosaical Geologies. 119

is ingenious. It removes many difficulties which any other
view of the subject has to contend with; it does away with
the necessity of those repeated revolutions, which, on no ground
but that it cannot do without them, the mineral geology is
continually having recourse to, and it refers similar effects to
similar causes. Throughout his whole argument our author
connects physical causes and events with the moral effects
they were destined to produce; and, it is for want of this
rational association of the two, that the mineral geology, per-
plexed with difficulties of its own creating, fails to draw correct
inferences from either. It sees, in the beginning and the end,
nothing but physical phenomena; it endeavours to explain
them by reference to physical causes alone, according to its
limited knowledge of those causes; it finds itself incapable of
doing so, without assumptions irreconcilable with and in
direct opposition to the Mosaical record, and therefore it con-
cludes that record to be false, or misinterprets and makes it
bend in every particular to rules drawn from its own pre~
conceived and chimerical opinions.

The time allotted to this supernatural revolution was twelve
months. At the moment when, by the subsidence of the old
earth, the waters began to flow into their new bed, God
grounded the ark on the summit of Mount Ararat : in seventy-
three days after this event, the tops of the mountains ap-
peared; and in sixty days more, the waters were entirely drained
off from the surface of the earth. The security of the ark
demanded this gradual transfer of the mass of waters, for, had
the former continents sunk at once, the rush of the waters to
fill the gulf must have hurried the ark into the tremendous
vortex—but it is represented as riding securely on the surface
of the universal ocean. ‘ The ark went upon the surface of
the waters.”

That the -sea once covered the whole earth, and that its
surface has undergone great destruction and depressions, and a
violent revolution since its first formation, is acknowledged by
both geologies, but the Mosaical admits only two revolutions,
whilst the mineral affirms them to have been numerous.

Our author then proceeds to shew that the general phe-
nomena of the earth may be satisfactorily referred either, 1. to
the creation ; 2. the first revolution; 3. the long interval that
succeeded it, during which the sea remained in its primitive
basin; or 4. to the second revolution. To the first cause
belong the sensible characters and diversities of all primitive
rocks and soils; to the second, those of their dislocation, frac-
ture, and dispersion; to the third, the water-worn appearance
of the larger and smaller fragments of rocks and stones, and
the moulding of the loose soil over the solid substrata, as well
as the vast accumulations of marine substances. Lastly, to
the second revolution, the excavation of valleys in secondary

120 Analysis of Scientific Books.

soils ; the heaping up of marine mineral masses; the secondary
rocks, and the confused mixture of the organic terrestial frag--
ments, once a part of the furniture of the earth that perished,
are as evidently to be referred.

Of the natural agencies employed by the Almighty in
the two great revolutions, our author supposes earthquakes
and yolcanoes to have been the most probable; and it is
well known that there is an intimate connexion between
them. Some geologists, however, reasoning from the limited
effects of existing volcanoes, have denied their sufficiency;
but, “‘ it is one thing to compute the power of a vol-
cano, and another thing to compute the power of volcanic
action ;—the possible effects of volcanic power, rendered
general within the globe, and acting simultaneously against
its solid crusts, without a regular vent to determine its issue,
cannot be measured by the effects of an individual voleano
acting on one point, at which it has found a channel to dis~
charge its violence.” The presence of water too in great
quantities in volcanic phenomena, which, from the actual situa-
tion of existing volcanoes, ‘ on islands or on coasts not far
from the sea,’ we may conclude ‘is a condition essential to
their existence ;’? and the evidence of their having prevailed
‘ anterior to the formation of valleys,’ “ that is, previous to
the depression of the earth’s surface,” are circumstances which
increase the probability, that their powers were called into
action in the first revolution. For, in the first place, at that
period water was in immediate contact with the entire surface
of the earth, and its admission, ‘‘ at one and the same mo-
ment, beneath a considerable extent of it, was able by the
new laws of volcanic action, directed by their author, to cause
at one and the same moment an equally extensive disruption,
and consequent depression of that surface.” In the second
place, ‘ the immense fusions of basalt,” as witnessed at the
Giants’ Causeway, the Island of Staffa, &c. &c., and which
the mineral geology considers as belonging ‘ to the most
ancient epocha,’ “ demonstrate a remote period of volcanic
effort in the interior of the earth, totally different in circum-
stance from the ordinary phenomena of conical volcanoes,”
(those now active,) “‘ and of which we have no experience
whatever except in those effects.’”? Thus our author contends,
that the unequivocal character of igneous fusion which per-
vades the great basaltic districts, is perfectly consistent with
the sacred record; and, “ if we superadd to the indefinite
extent of volcanic power, the ordination and direction of its
agency to a particular purpose by its Divine Author, we shall
at once perceive that it was an instrument, calculated by its
laws to operate to the fullest extent of the effects which we
here ascribe to them.”

The remains of animals of all species and climates are

a ee

Mineral and Mosaical Geologies. 121

found in vast abundance in the interior of the earth, and in
situations far remote from their natural localities, so that
exuvie of the inhabitants of the torrid zone are often met
with in the most northerly latitudes, and vice versd. The
mineral geology argues, therefore, that the animals to which
these exuviee belonged must have died, and consequently have
lived in those latitudes where they are found; and that they
could not have done so unless a revolution had taken place,
either in the nature of those animals, or in the climates of the
earth.

' But the mere presence of theirfossil exuvie in such discordant
situations is no proof that they either died or lived there. We
know that the animals to which they belong existed on the
former earth—that they were destroyed with it, and indiscri-
minately absorbed into the mass of waters, by which their
destruction was effected. ‘‘ If, then, it was physically possible
that they should have been transported by those waters from
the surface of the former earth into the bed of the former sea,
and if that bed is now become our habitable earth, it was
highly probable that we should discover such remnants of them
as have not entirely mouldered away ; and it will be much more
philosophical to resort to that possible cause, than to violate
by our conjectures the laws established either for the nature of
animals, or for the climate of the globe.”

But, on this supposition, the direction in which the waters
have transported those exuviee, seems to be diametrically oppo-=
site to their current ; for, if the former continents existed in
those tracts now covered by the Atlantic and Pacific Oceans,
when they sunk into the abyss, the waters must have rushed
from north to south, and how in that case, could the bones of
the elephant or rhinoceros have been found in Siberia?
** How could the sea, in moving from its bed, carry backwards
and deposit within its bed the spoils that it absorbed from the
continents which it had moved forwards to submerge?” ‘The
subsidence of the old continents was gradual—the limits or
coasts which circumscribed the sea receded gradually during
those subsidences—“ but its violence, continually discharged
against succeeding limits,” produced the common effect of
re-action and reflux of its waters, and this continued till the
subsidence was completed; and thus retiring currents were
formed, “‘ retrograding as the flux advanced.”

Such refluxes are known at the present day, between the
continents of Africa and America, ‘‘and the waters.of the South
Sea, stopped by the continent of Asia, fall back naturally to
the coasts of Chili, Peru, and Mexico*;” many other similar
instances might be adduced.

Let us then suppose (what must have been the case) all the woods and
forests of the former earth, of every latitude, uprooted, entangled together,

* Dela Lande. Flux et Reflux dela Mer. Tom. iv. p. 305

122 Analysis of Scientific Books.

and floating upon the hosom of the ocean; let us further suppose all tle
races of animals, of all climates, crowded confusedly in close contact, and in
numberless masses, implicated in those floating forests, and buoyant upon
the face of the waters, and operated upon by the impulsory powers of re-
tiring eurrents, tides, and winds. Itis impossible to deny, that such im-
mense Conjoined masses, presenting vast surfaces to the winds and retreat-
ing waters, would be driven before them to very great distances before
they would all be submerged. If the continents from which they came
were south of the sea bed, and if the sea flowed to the southward, they
would then be transported in a northerly direction, just as the waters of
the equatorial current, which fall against a western land, retrograde to an
eastern sea.——~Thus the spoils, successively gathered from the old conti-
nents, would have been driven over thenorthern parts of the primitive sea ;
would have been sunk upon different parts of its bed, and buried in its soils.
And if a great moral end was capable of tems effected by the operation,
a fact which the present argument renders indisputable, the direction of
these amazing monuments to their actual stations, by the instrumentality
of the natural agent, was in every respect consistent with his power and
intelligence who afterwards ‘‘ caused a wind to pass over the earth, that
the waters might be assuaged.”

To prove that the distance between the old equatorial and
present northern continents is not greater than might well have
been traversed by those immense floating masses, our author
mentions the fact of a vessel, almost under bare-poles, having
come from Halifax to Spithead, a distance of three thousand
miles, in thirteen days. The space from the equator to
Tobolsk, in Siberia, is four thousand miles, and the mouth of
the Lena is nine hundred miles farther. .

The substances thus transported must necessarily have been
imbedded in the yielding mud, in which they would ultimately
sink,—some less, others more deeply, according to the peculiar
circumstances arising from local causes ; and as the transport
was by water, and the bed that received them soft, they would
be ‘uninjured by trituration or fracture, and the bones of the
several animals so deposited would be found, as they fre-
quently are found, perfect and entire. But it has been ob-
jected that whole skeletons have not been found, and, therefore,
they could not have been transported; but wherever the animals
died, they must have died with their skeletons entire; and if
parts only are found, the rest must have mouldered away,—and
what difference could there have been, in this respect, whether
they had died where they were found, or had been transported
thither, and there deposited? Cuvier’s argument (for it is he
who advances it) makes rather against, than for the end to
which he adduces it.

But facts also are against him, for the entire skeleton of an
elephant has been found at Tonna, in Thuringia, another at the
mouth of the Lena, and one of a rhinoceros in the banks of
the Vilhoui. Thus we can account rationally for the discovery
of the confused fragments of animals of all climates in the
strata of our earth, and see how the bodies of elephants, rhino-
ceroses, &c., may have been transported from the torrid zone
to the north of Europe, and imbedded at the various depths at
which they are now found in England or Siberia, without re-

ee —

Mineral and Mosaical Geologies. 123

quiring any change either in the natures of the species, or in
the climates of the earth.

‘As to the multitudinous masses of bone found in caverns in Ger-

many, Hungary, and elsewhere, our author very rationally, we
think, concludes them to have been carried into those cavities,
(which must have existed then as well as now, in therocky bottom
over which the animals were transported,) by the action of the
water continually entering into and returning from them ; for
the returning water would not “ have equal power upon the
bodies with the entering water,” and consequently would leave
the bodies behind. “ So that when the soil was not sufficiently
soft to receive them, they would be driven forward and finally
urged into the inmost recesses of the caverns, where they
would afterwards be found in confused multitudinous and
exposed masses, with all the circumstances which they now
exhibit, And, because they would have been fixedly lodged
before their skeletons were stripped of their integuments, and
because the sea presently abandoned them, no appearance of
trituration would be discoverable in the bones.”
- The whole human race, with the exception of a single family,
is stated by the sacred record to have perished with the brute
creation. Why then have not human bones been found in a
fossil state, as well as those of elephants and other animals ?

The mineral geology has suggested the answer.

The place which man then inhabited may have sunk into the abyss, and
the bones of that destroyed race may yet remain buried under the bottom
of some actual sea.

The brute creation, without reflection and forethought, con-
gregate together by instinct when alarmed, and await in trepi-
dation the unknown evil. These, therefore, by the sudden
subsidencies of the land on the spots where they chanced to be
assembled, would have been surprised by the successive inunda-
tions, and carried away by the reflux of their waters. But the
human race seeing the threatened danger coming on them,
would retreat from the flood, gradually advancing on all sides,
and draw more and more towards the centre of the continually
diminishing circle, until, assembled in a multitudinous mass on
the last remaining portion of dry land, they would on its sub-
sidence be absorbed by the vortex occasioned by the conflux of
the two seas meeting from the opposite hemispheres, and thus
be carried down with violence into the depths of the new sea;
“ where their exuvize must remain for ever uninvestigable by
man.” Moral considerations strengthen the probability that
this was the course of that tremendous event, for the sufferings
of the condemned and hardened race were thus protracted by
their endeavours to escape from the catastrophe, till they had
worked their destined effects.

A similar mora) reflection will furnish us with a sufficient

124 Analysis of Scientific Books.

reason why the exuvice of animals are occasionally met with,
whose species no longer exist on the earth. Physical science
unconnected with moral, cannot solve the difficulty, nor can it
be expounded but by reference to the power and will of God;
who, for reasons known only to the counsels of his divine
wisdom, was pleased, when he communicated to Noah the
species he designed to preserve ‘‘ to keep seed alive upon the
earth,” to except some from that preservation.

Further on, our author mentions the singular fact, that the
Arabian camel, (that with one hunch,) is not found wild in
any part of the earth, existing only as the property of man,
and deduces an ingenious inference from it, in opposition to ~
an assumption of the mineral geology ‘“ that the revolution
which destroyed the animal races of which we discover the
fossil exuvie, was different from that which established the
progenitors of the human race in Asia.” The circumstance
can only be rationally accounted for by considering those
animals as the descendants of the pair preserved in the ark,
as all the present human race are the descendants of Noah,
and, that from their great utility, none have ever since been
suffered to escape from the dominion of man.

The domesticity of the entire race of this peculiar species of camel, ig
therefore a living and perpetual evidence both of the revolution in which
the whole animal creation perished, PxCeP HOE A reserved few, and of that
bd in which the human race was first established on the continent of

Because animal and vegetable relies are found buried in the midst
of soils, which are too confidently pronounced the most ancient secondary
strata, and because land animals are found under heaps of marine pro-
ductions, Cuvier at once assumes that the various positions of these relics
constitute evidences of as many different revolutions.

They are, however, easily explained from the data of the
Mosaical geology. After the imbedding of the innumerable
land animals in the sands or slimy bottom of the primitive sea,
violent and particular agitations within its basin may have
dislodged and put in motion, especially in the latter stages of
its draining, enormous masses of its loose soil, and have driven
them, loaded with marine substances, upon the beds in which
the terrestial animals had ‘previously sunk; and repetitions
of such events, which may and must have occurred during that
disorderly crisis, would produce various alternations of such
depositions, ‘* diversified by different circumstances, and re-
ducible to no rule of regularity and order.” As to the fresh-
water shells alleged to be found in some of these accumula-
tions, a pertinent doubt is suggested by Mr. Greenough, whe-
ther the distinction between them and marine shells be so cer-
tainly ascertained as to allow of a conclusive argument founded
upon that distinction.

Our author argues very forcibly on the impossibility that
unconfined waters, diffused originally over a compact, extended,
and nearly horizontal surface, should have formed valleys, or

Mineral and Mosaical Geologies: 125

channelled out the beds of the rivers in which they now
flow. There is no reason for supposing the Rhine and the
Euphrates to be deeper or wider now than they were in the
days of Cesar and Cyrus; but if their waters had originally
formed their own beds, since the action is continually going
on, they ought to be continually increasing in width and
depth. Valleys and mountains are obviously co-ordinate and
correlative—“ a mountain signifies nothing but an elevation
above a valley, and a valley nothing but a depression below a
mountain,” and the cause of these differences of elevation has
been already examined. ‘‘ The varied system of valleys, and
their intimate and direct relations both to mountains and
rivers,” is referable only to the divine wisdom which ordained,
and gave to the mountains the very forms essentially necessary
for ‘‘ separating the beds of those rivers from one another ; and
serving moreover, by means of their eternal snows, as reservoirs
for feeding the springs.” The general system of rivers is to the
earth what the vascular circulating system is to the animal and
vegetable structure, the means by which the necessary fluids
are distributed from one extremity to the other, and rivers like
blood-vessels, are ‘‘ so skilfully and equally distributed over
the whole surface, so artfully diverted in many places from the
nearest seas, and conducted through extensive inland regions,”
that they incontestably argue supreme intelligence in their
designer.

On the formation of coal our author touches with the judi-
cious caution which the obscurity of the subject demands. He
concludes with Mr. Hatchett, to the probability of its vegetable
origin ; and from the failure of that celebrated chemist to pro-
duce bituminous coal, in his experiments on vegetable sub-
stances of land growth, and for other reasons, suggests that the
beds of natural coal ‘‘ were perhaps immense accumulations of
fuci, &c., loaded with the various animal substances which
shelter among them, and which were overwhelmed by vast ag-
gregations of the loose soil of the sea, in the course of its re-
treat, and were left for decomposition by the chemical action of
the marine fluid which they contained, and with which the en-
closing and compressing soils were saturated *.”

In the remaining portion of the work, our author ascribes the
covering of the new earth with vegetation after the second revo-
lution, to a fresh and immediate act of God; and infers, from
the olive-leaf brought by the dove to Noah, that it was created
in full and perfect maturity. He supposes it probable, also,
that new animal species were at the same.time created, to sup~
ply the place of those which it was the will of God to destroy

. * “There is every reason to believe, that the agent employed by nature
in the formation of coal and bitumen, has been either muriatic or sulphuric
acid,”’—Hatcuetr, Phil. Trans, 1606, p. L11.—R.

126 Analysis of Scientific Books.

utterly by the deluge. He shews by a learned argument, that
the description of the rivers in the garden of Eden, (Gen. it.
11—14,) is a marginal gloss in a transcript of the original
history, which in time became incorporated with the text; and,
consequently, that no inference, as to the identity of the for-
mer and the present habitable earth, can be drawn from that
description. He then concludes, from the general result of the
preceding inquiry, that the numerous revolutions assumed by the
mineral geology “ are the offspring of defective investigation
and unregulated fancy,” and are all reducible to those two
only which are recorded in the Mosaical history ; and that in
the second question, “ relative to the changes which this globe
has undergone since its first formation, and to the mode by
which those changes were effected, the Mosaical geology has
maintained the superiority over the mineral, which it established
in the first question relative to the mode by which that first
formation was produced.” A code of general principles,
“‘which may at all times guide our view in contemplating the
phenomena apparent in the globe, and secure us against the
fascination of unsubstantial theories,” followed by some valu-
able general reflections, closes the work.

We have thus given a pretty circumstantial account of this
very interesting volume. The length of our review may per-
haps seem to bear a somewhat too large proportion to the size
of the book ; but its value is not to be estimated by the number
of its pages, and we could not, in justice to our author, con-
dense his matter into a smaller compass. Indeed, so pregnant
is it in argument, that nothing but a careful perusal of the work
itself can give a perfect idea of its merit. The subject is inves-
tigated with logical precision, from the commencement to the
conclusion. Nothing important is omitted or slurred over, that
can fairly be adduced on either side of the question—all is can-
didly discussed, and the merit of every statement critically
examined. If there be any thing in the work that we think
might be improved, it is, that sometimes, though rarely, there
is a little unnecessary amplification and repetition; and in one
instance we do not very clearly understand the author’s mean-
ing. We allude to the part (not noticed in the body of our
review) relating to the hebdomadal computation of time. We
do not see what exact portions of time he would comprehend
in his month and year, nor how those portions are to be de-
fined. We wish he had been rather more explicit on this head,
and that he had given us the result of Frank’s attempt to con-
struct a true fundamental chronology, founded on the golden
period of the jubilee, which he alludes to.

The principal features of the work appear to us to be, the
inference the author deduces from the sacred record, of two

Mineral and Mosaical Geologies. 127

distinct revolutions, or periods of destruction, of the surface
of the earth: his mode of reconciling the accounts of the
creation of light on the first day, and the sun’s visible ap-
pearance on the fourth: the reasons why fossil remains of
some animals are found in climates uncongenial to their
natures, and of others whose species are utterly extinct; as
well as why fossil human bones have never been found at all.
The ingenuity, too, with which he proves the incompetence
of mere physical phenomena to decide on the mode of first
formations, is extremely striking, as well as many other
parts of the work, which we have not room to enumerate.
Our author’s claims to a high rank asa scholar are evident
throughout; his corrections of the sacred text, in the second
part, evince a perfect knowledge of the Hebrew, as well as of
the classical languages ; and his remarks on Deluc’s hypothesis
of the indefinite period of the Mosaical days of creation, and
Saussure’s nonsensical rhapsody from the summit of tna,
vindicate his pretensions as a sound and formidable critic.

In conclusion, we earnestly recommend this book to the se-
rious attention of our readers. Its philosophy is founded on
that of Bacon and- Newton; its reasonings on the mode of first
formations and secondary causes, are in strict harmony with
that philosophy, and at least as plausible as any that have been
advanced by the Huttonian and Wernerian schools. Nor must
the adherents to those systems object, that its referring many
effects to the immediate agency of divine power, is merely a
subterfuge to cut the knot of difficulty, until they can either
teach us how to untie it, or find a more probable cause to which
it may be attributed. When, to these considerations, we add its
excellent moral and religious tendency, we think every candid
judgment will admit, that the ‘“‘ Comparative Estimate” has
accomplished its intended object; and that it is indeed well
calculated to “relieve the minds of earnest and sincere inquirers
from perplexity,” by contravening the pernicious dogmas of
pseudo-scientific scepticism, whether derived from the fossil
exuvie of a former race, or the recent reliquize of a modern
dissecting-room—whether founded on the chemical contrivances
of a crystallizing chaos, or the profound speculations of medul-
lary matter!

128

Art. XVII. ASTRONOMICAL AND NAUTICAL
COLLECTIONS.

No. XIII.

i. Empirical Elements of a Table of RerRaction: computed
from Observations communicated and reduced by SrerpnENn

GroomBrinGE, Esq., F.R.S.

Proressor ScHuMACHER has lately published a very useful
little volume of Permanent Auxiliary Tables. But with regard
to the subject of Astronomical Refraction, he has left it entirely
undecided, by which of the many systems a computer will be most
justified in correcting his observations ; so that itis probable that
almost every unprejudiced and diligent astronomer will prefer
those which appear to be the most elaborate, or of which the
author or authors have acquired the highest mathematical repu-
tation; a reputation which but too often tempts its professor to
look down with contempt on physical truth.

The mode of examination, exemplified by the Editor, in the
former numbers of these Collections, appearing to him to be the
only unexceptionable mode of obtaining a fair determination of
this complicated question, he has prevailed on the kindness of
Mr. Groombridge to add a number of later and more extensive
observations to those which he had before communicated ; and
their ultimate results are here exhibited, with the addition of
some further steps towards an immediate application to prac-
tice, or at least to a more satisfactory comparison of the merits
of the different tables actually existing: and these results are
not made public with the less readiness, because they appear, in
some respects, not to agree quite so well with the Editor’s own
theory, as the former ; but confirm the suspicion, which he for-
merly entertained, that the corrections of his table are some-
what more strictly appropriate to the different mean tempera-

Astronomical and Nautical Collections. 129

tures of various climates, than to the occasional variations at
any one place.

The steps of the computation, with a little variation from
those before enumerated, have been nearly these. First, to
find the mean apparent altitude for each star. Secondly, to
find the mean height of the exterior thermometer. Thirdly, to
reduce all the refractions to their mean state of pressure, with
the barometer at 30 inches, applying corrections, simply pro-
portional to the differences, in the usual manner. Fifthly, to
find the mean refraction, and the several differences from the
mean, and to add together such of them as are regular, that is,
such as agree with the differences of the thermometer in their
character, and to subtract the sum of such as are irregular.
Fifthly, to divide this result by the sum of the differences of the
thermometer, in order to obtain the experimental correction for
temperature ; which must, however, be increased by the varia-
tion of refraction corresponding to such a supposed change of
altitude. Sixthly, Mr. Groombridge having always reduced the
temperature of his interior thermometer to 55°, in registering
the heigit of the barometer, it will be necessary to make a slight
correction for the difference of this temperature from the mean
height of the exterior thermometer, in order to continue the
mode of computation before adopted. Seventhly, it is obvious
that if the tables and the observations were both perfect, the
correction for temperature, thus determined, ought also to re-
produce the observed refraction from the standard temperature
of the tables ; but this is seldom correctly true, and least of all
where the number of observations compared are few, although
they may not deserve to be wholly rejected. We may, therefore,
divide the difference of refraction from that of the standard tem-
perature, as exhibited in any tolerable tables, by the difference
of the mean temperature from the standard temperature of those
tables, for the joint result of the observations and tables.

130 Astronomical and Nautical Collections.

Eighthly, this operation evidently supposes the standard re-
fraction of the tables to agree with the observations ; but, as a
test of this agreement, it will be proper to divide the sum of
the whole amount of the corrections, additive and subtractive,
by the sum of the several differences from the standard tempe-
rature respectively : and it appears that in order to bring these
quotients to equality, it will be necessary to alter the supposed
standard of the tables to 46°, instead of 48°. Ninthly, we
may ultimately adopt, as the best empirical correciion to be
derived from that set of observations, the mean of the two cor-
rections thus obtained. Tenthly, the last column of the table
contains the quotient of the refraction at the standard tempera-
ture, divided by this mean correction : it will be justifiable, in
the present case, to reject two extravagant numbers, derived
from 7 and 9 observations respectively ; and, in order to satisfy
the most scrupulous, we may venture to reject the least of all
the numbers: hence, for the mean of the whole 20, we have
438.3; for the mean of the lower 10, 434.3, and of the upper
10, 442.3; half the difference 4, applied to the means, gives for
the lower extreme 430.3, and for the upper 442.3, the difference
of altitude being 7° 2’: and we may safely adopt, as the general

empirical correction for each degree of temperature, as far as

R
De CHG LXBt
430 + 2 axt.° eee

observed ought also to have been rejected in this computation, as

these observations go, the formula

affording an irregular result, or too great a refraction: but it re-
mains to be ascertained whether the error is in the observation or
in thetable: and, in fact, the empirical formula, here investigated,
will not afford a series of mean refractions agreeing very accu-
rately with any existing table; although we may safely infer from
it, that the French astronomers were too precipitate in neglecting
the true correction for temperature which their own theory
would have afforded them, in opposition to the actual observa-

Astronomical and Nautical Collections. 131

tion of Bradley, which had induced him to employ a correction
somewhat more considerable than the mean of the results from
Mr. Groombridge’s observations.

EMPIRICAL TABLE OF REFRACTION.

Correction for — 1° Fahr,
“Ob Ob F Dim
Se Se a + rm ivisor)
only | and 'T. | N. A,|Bessel | T.

'
Mean

Mean apparent Fah {Retraction
an

STAR, Obs+ Altitude

(oT a te} , “ a“ “ a u" W

-|16]1 18 42.6] 49.2]22 23.3] 2.97}—(6.0)} 4.3 |3.9 |2.7
25|1 30 9,5]38.1/21 38.0)3.295| 3.2 |4.0]3.7 |2.6 | 349
-117/2 0 8.1]52.9/18 11.1]2.17| 1.8 |3.2 |30 |2.2 | 630
44|2 17 35.2|31.9|17 38.9|3.01] 1.8 |¢.8 |2.7 |2.1]}| 406
13]}2 30 53.4/56.7|}15 51.6/2.35] 2.9 |2.7 |2.5 |1.9 | 404
g|2 41. 2.2/56.3]15 13.3]1.17] 13 125 |2,4 {1.8 |(818)
5/2 51 34.5]28-7/15 32.7|2.99] 1-6 |2°5 ]2.3 |1.8 | 377
12/2 2 29.9/389]14 44.7]2.43} 2-0 | 23 ]2.2 |1.8 |(324)
10/3 6 509|54.3/13 53-5]2.39] 3:3 [2-2 ]2,1 |1.7 | 352
8|3 53 37.5|39-8]12 17.4|2.00] 1:4 [1.8 ]1.8 |1.4 | 406
10/4 7 2.5132.8]12 1.6]2.53] 1.67] 1.66] 1.76]1.45] 350
15|4 49 8.7|38.6]10 21.7]1.86] 0.58] 1.43] 1.45/1.23] 474
ae ..|12]4 55 27.2|43-5]10 10-0]1-34] 0.86] 1,40] 1.44|1.20] 499
11 Lacert. |16]4 55 55.7|38.3]10 12.8]1-47| 0.80] 1.40} 1.44/1.20] 491
e Aurig. ..| 7/5 9 17.7/58.2| 9 29.8] 1-22} 1,30] 1.34] 1.37/1.16] 507
~A U. Maj. {11/5 27 58.5/33.8} 9 28.5]1-44) 1.03) 1.27] 1.29/1.14] 420
x Pers.....|13|5 44 33.2/53.8| 8 41.4]1-16] 1.62) 1.21} 1.22/1.06] 442
wo U. Maj...}13]5 47 55.9/33.6| $ 57-5]1.83] 0.73] 1.20] 1.21]1.05] 393
ja Cygni ../29/6 13 19.7/38.5] 8 20.8] 1.19} 0.49) 1.11} 1.14]1.00] 5438
8 Aur. ....| 2316 30 26.4]58-3| 7 46.4]1.10} 1.09] 1.03] 1.66/0.93] 488
YU. Maj. | 7/7 6 8.5|33.7| 7 31.4/087| 0.45} 0.95] 0.96|0.87] (653)
Capella ...|24|7 22 13.6|61.8] 6 58.0]1.18} 1.59}0-93] 0.43 |0.84} 340
+ Here.. ..| 1318 20 21.3/39.9] 6 0.86] 0-82] 0.84|0-80] 372

il. Errors of the Lunar Tables for 1819 and 1820. Computed
from the Observations made at Greenwich.

(See Collections IIT. ii.)

Greatest Error of

Mean Error three consecutive
Laplace om — observations 1m
and Burg. Long. Lat. Longitude,
" “ ”
1820 Eom WO 16.6
—1.7
Laplace and
Burckhardt. +4 ls 5 7 11 0 y
1820 3 rans :
1821 3 eer 4.3 1 es |

182 Astronomical and Nautical Collections.

iii. Mr. RumkeER’s rediscovery of Encxe’s triennial Comet.
In a Letter to the Editor. (See Collections IV. ii.)

Summer Sotstice, 1822, observed in Paramatta Obser-
vatory, with a repeating circle of Reichenbach. The observa-
tions of the Solstice are partly by the Governor, partly by
myself.

rue 2c. Isle
of Trop, of
So

Day of the} True Zen. Dist. of
onth the Sun’s Centre

Reduction to
the Solstice

Cor, for
Sun’s Lat.

56 41 49.63/34 40.67/4.0.41157 16 30.7 129.97/55.4
46 59.97129 33.96] 0.26 34.19129.8 156.0
59 52.98|16 38.49|—0.19 31.28|29.8 |63.0

57 3 29.98|13 7.82] 0.29 37.51129.85159.5

6 30.1910 3.52) 0.31 33.40130.09159.0
9 11.80] 7 22.98] 0.41 34.37|30.06.54.0

13 19.11] 3 16.16} 0.39 34.88 29.90159.5
14 42.88) 1 49.86) 0.32 32.42)/29.81|52.0)
15 44.9 | 0 48.41} 0.22 33.31|29.92/51.0
16 18.51 ttr7t 0.12 30.16|29.90!51.5
16 14.57 13.07/+-0.17 27.81129.71|57.0
9 2.6 | 7 29.89} 0.81] 33.3 |30.04/61.2
6 20.16/10 11.38) 0.85 32.39|29.99|59.0
3 12.41/13 17.27] 0.88 30.56/30.00/56.
uly 1 [56 59 45.81]16 47.43) 0.88 34.12/30.00|56.0
Méan:. tcc. Or Lome i087
Lunisolar nutation — 6.77
Reduction to Jan. 1, 1822 . 57 16 25.917
+ ~ 0.22
Mean Z. D. of Tropic of gs . . . 57 16 26.137

The Winter Sols. gives m. Z.D. of Trop. of 810 21 2.237

Difference .. . 46 55 23.9
Hence mean obliq. Jan. 1, 1822, 23 27 41.95

Supposing the mean obliquity Jan. 1, 1822, to have been
23 27 44.26, we obtain for lat. of the observatory 33 48 41.97.

I observed the following occultations of fixed stars at
Paramatta,

Astronomical and Nautical Collections. 183

Mean Time.

March 28, 1822, % 7 magnitude Tauri immers. 6 54 30.2
30 5.6 supposed vGemi.. . . .. 9 19°28°5

April 1 6 Cancri . ». . 8 58 21.8
10 aly 5 immers.18 35 47.4

ae emersio 19 14 27.9

Sidereal Time.

July 11 5.6 Pisc. .immers. 2 1 0.4

From the occult. of Antares I find the mean time at Paramatta
of true conjunction,—
Perimm. 17 29 8.8 —5.54 dL +5'89 dS—0.56 dx
emer... . 19.824+2.44°.. —3.17 . —2.06
From the Nautical Almanac follows the mean time of ¢ in
Green. 7 25 12.5. Hence long of Par. 10" 4’ 1.8; this may,
however, be corrected by the Green. Lunar Obs. on that day.

I assumed

a for ratio of earth’s axes:

Opposition of Mars, February, 1822.

These observations are a mean of several observations about
the meridian, each being singly reduced to the time of culmina-
tion. I made the observations with a repeating micrometer, ap-
plied to a telescope on an equatorial stand, and did not extend
them beyond-15’ on each side of the meridian.

Feb. 15 Mars less AR gar rigs 97%
eek tonis ¢ 1'47".33 Mars N. of iQ 2! 3515

16 Mars tra’ 0 6. 05 Mars South me 0 34.8
than446 Mayer 446M. . A
On the 15th of February, at the time of culmination, Mars
was therefore 2’ 35.15 north of i Leonis and on the 16th, when
on the meridian 0’ 34.84 south of 446 Mayer, which latter
star it must have eclipsed little after passing the meridian ;
clouds prevented me from seeing it: thence the parallax of Mars

might be inferred.
Comet of Encke.

I did not see this comet before the second of June, 1822. I
send you here my observations thereof, which I believe to be so
correct as the position of the stars which I used for comparison,
taken partly from Piazzi, but chiefly reduced from La Lande
Histoire Céleste. :

K 2

134 Astronomical and Nautical Collections.

Sinereal Time | Mean AR. Mean Dec.

June 2 | 10 39 25 51.31 17 39 46.3 North
20571 16: 53.0 HS
0.0} 16 4 36.7.

13 26 5
11 17 25 | 12 31 ee
11 20 0 43.8| 10 29 49.5
11 24 39 ek oS satin, ‘
nets a ai
Pr ar
Pog gpaginn
4 33 40.

1 29 43.7 South

3 14 29.1.

114 12 20.5} 7 8 ——.
115 47 41,7} 9 9 48.4.

After the 23d the moonlight was too bright, and after full moon
the comet was too faint to permit observations to be made.

8 digits of the sun will be eclipsed at Paramatta on Aug. 17,
ia the morning. But the eclipse will be total at Cape Bedford,
in lat. 15° 27’ south, and long. 145° 30’ east.

Dear Sir, I beg you will dispose of these observations accord-
ing to your pleasure. *** Your most obedient Servant,

July 23,1822. Cuas. RUMKER.

Astronomical and Nautical Collections.

135

iv. Predicted and observed Places of the Principal Stars. By

1756
comp, with

1813

Ann. Var.
1818

= 20.09
— 19.85

—17.40
—14.59
—13.41
= 7.92
— 4.54
meee
— 3.80
1.36
441
7.12
8.63
8.02
+ 15.19
+ 17.23
+ 19.26
+ 20.04
+ 19-98
+18.94
+ 18.15
+ 18.97
+ 15-30
+ 15.32
+414.74
+ 12.45
+ 11.72
8.59
4.57
3.08
0.67
3.02
— 8.34
— 9.06
— 3-56
— 10-66
— 10-68
— 12-63
15-07
— 15-68
— 17-27

++++ /

l+t+++

— 19.32
= 19.95

Ne.

O@Ostaner Ot»

Names of Stars.

y Pegasi ....
a Cassiop....
Polaris......
a Arietis eooe
PORCCUE wan con
a Persei ...,
Aldebaran ..
Capella ....
Rigel «0% c0~

|B Tauri ....

a Orionis....
Sirius ......
Castor ....0
Procyon ....
Pollux, Sid's ¢
a Hydre ....
Regulus ....
a Urs, Maj...
B Leonis .,..
y Urs, Maj...
Spica Virginis
1 Urs. Maj, ..
Arcturus..,,
F ‘ 2 Librae

B Urs. Min...
a Cor. Bor...
a Serpentis ..
Antares ....
a Herculis ..
a Ophiuchi ..
y Draconis ..
a Lyre seeeee

abs "
a quiz oe
B

1} aCapricor.
a Cygni ....
a .

B ‘ Cephei ..
a Aquarii....
Fomalhaut ..
a Pegasi

a Andromede

AR 1 Jan. 1823

m s

4 8.09
30 31.29
57 46.38
57 13.99
53 2.29
11 44.48
25 46.58
3 37.83
6 2.21
15 6.76
5 35.66

NNNQOUAAANPROWD mM COO

9 18 53.50
9 58 56-36
10 52 43-4]
1140 1-66
11 44 28.63
13 15 52.91
13 40 33.54
14 735.61
14 40 54.93
1441 6.36
14 51 19.53
15 27 11.95
15 35 33.53
16 18 34.23
17 6 35-00
17 26 43-49
17 52 30.14
18 30 56.98
19 37 50.82
19 42 8.94
19 46 37.27
20 7 49.91
20 8 13.69
20 35 24.19
21 14 21.05
21 26 20.44
21 56 41-55
22 47 50.97
22 55 57-20
23 59 15-61

Star’s
Predicted N.P.D. Observed. obs.
1823. South of
predicted
1756 and 1813 eee ee place.
fe) 4 “ Oo 7 a “
75 48 0.11 | 7548 2.3 2.2
34 26 4.23 | 3426 5.7 15
ss °7.5
67 22 42.60 | 67 22 44.4 1.8
86 36 34.86 | 86 36 36.8 2.0
40 46 38.34 | 40 46 39.0 0.7
73 5116.17 | 7351 17-7 ee
44 1135-11 | 44 11 36-8 1.7
Q8 24 46.44 | 98 24 48.4 2.0
61 33 5.74 | 6133 6.6 0.9
82 38 2.11 | 8238 4.2 21
106 28 45.35 |106 28 48.7 3-4
57 43 58-08 | 57 43 59.1 1.0
84 19 40.75 | 84 19 43.2 24
61 33 16.76 | 61 33 17.1 0.3
97 53 43.20 | 97 53 44.5 1.3
77 10 15.00 | 77 10 15.4 0.4
27:17 44-16 | 2717 43.8 |-0.4
74 2617:73 | 74 26 18-1 0.4
35 1915-18 | 3519 14.8 |—0,4
100 14 0.73 |100 14 0.7 0.0
39 47 59-60 | 39.47 59-5 |—0.1
69 53 28.83 | 69 53 29-2 0.4
105 17 55.67 |105 17 pat 0.6
105 15 11.91 |105 15 19.5 ,
15 716.38 | 15 715.7 |—0.7
6241 0.07 | 6241 0.6 0.5
83 036.52 | 83 0 36.6 0.1
116 142.50 |116 1 44.1 1.6
75 23 59-70 | 7524 O.1 0.4
77.18 9.74 | 77 18 10.6 0.9
38 29 10.31 | 38 29 10.5 0.2
51 22 30.37 | 51 22 31.2 0.8
79 48 35.58
81 35 28.31 | 81 35 29.5 1,2
84 137.94
103 2 48.83)|103 2 49.6 Lo
103 5 buss 103 5 6.6 ‘
45 20 50.80 | 45 20 59.4 1.6.
28 9 42.20 | 26 9 42.8 0.6
20 12 53-78 | 20 12 54.0 0.2
Q1 10 28-85 | 91 1031.4 2.5
75 44 38.52 | 75 44 41.8 3.3
61 53 10.75 | 6153 12.5 1.8

Joun Ponn, Esq., F.R.S., Astronomer Royal.

From the Philosophical Transactions.

Nore, The sign — in the last column denotes that the Star has been found
north of its predicted place.

136

Art. XVUI.—MISCELLANEOUS INTELLIGENCE,

I. Mecuanican SCIENCE.

1. Economical Bridge.—A bridge of suspension, or rather
tension, has been constructed not long since by M. M. Seguin>
near Annonay, department de l’Ardéche, after the model of
those constructed by the indigenous inhabitants of America*.
The following account is taken from a description of it by M.
Pictet. Bb. Univ. xxi. 123.

At the place where it is constructed, the river over which it
passes is confined by rocks which have furnished. strong points
of attachment for the bridge. A band composed of eight iron
wires, each the |, of an inch in diameter is attached by its
extremity to an iron bolt fixed in the rock; it then crosses the
river at a height of 10 feet above it, and on the opposite side
passes round a horizontal pulley three inches in diameter, also
made fast to a rock. The band returns parallel to its first
direction, passes round one pulley to preserve the parallelism,
and then on to another about 16 inches distant, from which
it again proceeds over the river and passes round a second
pulley on that side, and finally returns to the side from which
it parted, and is made fast to a bolt in the rock. Thus it
crosses the river four times. Small cross pieces of wood are
attached at intervals to these reduplications of the band, and
oyer them are placed the planks, parallel to the wires, which
form the foot-way of the bridge. Two other bands of wire are
carried across the river at a convenient height on each side of
the bridge, to serve as hand-rails; they are connected by
descending wires to the external bands of the bridge: and, to
prevent every lateral motion the bridge is made fast at the
middle to some large stones in the bed of the river.

This bridge though of a structure so light as to occasion
fear on the first time of going on to it, is yet so steady and
strong that no sensible bending or vibration is perceived in
passing over it. It is 2 feet broad, and 55 feet long. The
weight of iron wire used in its construction was about 24lb.,
and the expense of the whole of the materials amounted to
little more than 35 francs. The expense of labour is estimated
at about 15 franes, so that 50 franes according to this account
would pay for the whole.

*. See also vii, 53.

Mechanical Science. ABY

2. Hydraulic Instrument for raising Water.—It is well known
that ifa glass vessel containing water be placed in the centre
of a whirling table, the water, by the centrifugal force, will be
thrown from the centre outwardly, and the surface of the water
will assume a form approaching to that of a parabola.

Dr. Crelle, architect to the King of Prussia, has accordingly
made the bent tube in his model of the improved Hessian
machine of a parabolic shape, and on being placed in a certain
depth of water, the water entering below at a hole in the centre
of the tube, is by the quick whirling movement given to the
machine, raised and delivered at the upper ends of the tube
into the circular trough, and runs out from thence at a
spout on one side of it. Many tubes may be thus combined,
and the quantity of water raised be increased accordingly.
The value of this machine on a large scale is not known, but
certainly this is the best form of it.—Tech. Rep. iii. 99.

3. Hydroparabolic Mirror—standard Measure.—Mr. Busby,
well known as the constructor of a hydraulic orrery, applies
the syphon as a generator of rotary motion, A floating circular
vessel is placed in a reservoir of water, and has a syphon
attached to it, one leg of the syphon dips into the water of
the reservoir, the other passes over the side of the reservoir to
a lower level than the water within, and discharging a minute
stream by a lateral aperture, gives to the floating vessel a
perfectly equable revolving motion. By means of it, Mr. Busby
says he has produced a perfect hydroparabolic mirror fifty-four
inches in diameter, thus being able to create. any magnifying
power ad libitum. He refers to it also as a means of obtaining
an universal standard of measure. Thus, a given parabolic
speculum will invariably be formed by any given rotation at
any known level and latitude, and the focal distance of any
parabola must under those circumstances be always a given
dimension.—Tran. Soc. Arts, xl.

4, Feeding of Engine Boilers.—Thomas Hall, engineman to
the Glasgow Water Company, having remarked the waste of
fuel which occurred at those times when a steam-engine stopped
working, as at night, &c., was induced to alter his mode of
feeding the boilers with water, with a view to prevent as much
of this waste as possible. Instead of letting in a continual sup-
ply of water, equal to the portion converted into vapour, he
took every opportunity, when the engiue was stopped for a

138 Miscellaneous Intelligence.

sufficient time (30 or 40 minutes,) as at meal time, night, &c.,
of introducing water into the boiler to as much as 18 inches
above its usual level, and it was continued to this higher level
as long as the engine was off work. When labour was re-
sumed, there was therefore an abundant supply of hot water in
the boiler, the steam was ready, and no increase of fire, to heat
freshly-introduced water, required. The saving which arose
from this mode of management was 25 per cent. of the fuel.
The apparatus for feeding the boiler in this manner with accu-
racy, and without trouble, is very ingenious, and is described
in the Zrans. Soo. Arts, xl. 127.

5. Improved Printing.—A great improvement in printing is
spoken of as the invention of Mr. Church, of America, who
is now in London, constructing a machine, which it is hoped
will be successful. The improvement extends to casting as
well as composing, and by simplifying the casting process, and
saving the expense of distributing, he proposes to compose
always from new types, remelting after the edition is worked
off. The recasting for every new composition is connected with
the regular laying of the types, and when thus laid, it is in-
tended to compose by means of keys, like those of a piano-
forte, each key standing for a letter, or letters. By these means
errors would be avoided in the composition, and the progress
would be far more rapid than at present.

The above is the only account we have been able to procure
of the improvement ; and we gather from it, that it should ra-
ther be considered as intended, than as realized.

6. Casting of Stereotype-plates, by M. Didot.—This method
consists in striking moveable characters (cast of a composition
hereafter to be described,) into lead, without the assistance of
heat. Moveable characters formed of that composition, cast in
the usual manner, are composed line by line, according to the
common methods, till a page is formed. This page is placed
in a frame of suitable dimensions, and in this frame two quadrats
are placed, which, by means of screws, press all these move-
able letters so as to form a solid mass. A brass or iron frame
is made to the size of the page, and a plate of iron is fastened
to it by screws, to serve as a bottom ; this frame is then filled
with a plate of pure lead. The whole being thus prepared, the
page composed of moveable characters is put upon the lead

Mechanical Science. 139

intended for a matrix; it is then placed under a strong press,
which forces down the letters into the lead, which thus becomes
a solid matrix. In this matrix as many stereotype forms may
be cast as can be wanted. The composition for casting the
moveable characters is formed of seven parts by weight of lead,
two of regulus of antimony, and one of an alloy of tin and cop-
per, in the proportion of nine of tin, to one of copper.—-New
Monthly Magazine, ix.71.

The alloy with which to cast the plates should also have been
described. —Eb.

7. Calculating Engine—At page 222, of our 14th volume,
we have inserted a notice of Mr. Babbage’s very curious
investigations on the application of machinery to the purpose
of calculating and printing mathematical tables. It gives us
much pleasure to be able to inform our readers, that he is dili-
gently pursuing this very important subject, and that the re-
sults of his labours are in the highest degree satisfactory.

8. English Opium.—Messrs. Cowley and Staines, of Winslow,
Bucks, have cultivated poppies for opium with such success, as
to induce the belief that that branch of agriculture is of national
importance, and worthy of support. In the year 1821, they pro-
duced 60 Ibs. of solid opium, equal to the best Turkey opium,
’ from rather less than four acres anda half of ground. The
seed was sown in February, came up in March, and, after pro-
per hoeing, setting out, &c., the opium gathering commenced
at the latter end of July. The criterion for gathering the opium
was, when the poppies, having lost their petals, were covered with
a bluish-white bloom. The scarificator, an instrument contain-
ing five small blades, was then applied to them, horizontal inci-
sions being preferred, because the juice was not so apt to run
from them before inspissation. After being scarified in one
aspect, the head was left until the juice was coagulated (about
two hours,) it was then removed by gatherers, and fresh inci-
sions made on other parts. The poppies were found to produce
opium freely, until the third or fourth incision, and some of
them even to the tenth. Opium was gathered daily until, at
the rate of 30s. per lb., the produce would no longer bear the
expense; 97 lb. 1 oz. were procured at an expense of
311. 11s, 24d., and this, when evaporated sufficiently in the
sun, produced above 60 lb. of properly dried opium.

140 Miscellaneous Intelligence.

The poppies stood on the stalks until they began to turn
yellow (Aug. 18,) they were then pulled and laid in rows on the
land, and, when sufficiently dry, the heads were gathered,
thrashed, and the seed separated by coarse riddles, and cleaned
by fine sieves and a fan. The seed amounted to 13 ewt., and
was expected to produce 71} gallons of oil. The oil-cake
was given to pigs with great advantage, and also to stall-feeding
cattle. An extract may also be made, by cold infusion, from
the capsule of the poppy, eight grains of which are equal to one
of opium; an acre produces 80 Ib. of it. The poppy straw
when well trodden in the yard, and laid in a cempact head
to ferment, makes excellent manure.

The, quantity of opium consumed in this country is supposed
to amount annually to about 50,000 lb,, exclusive of exportations.
This quantity (say Messrs. Cowley and Staines), our experiments
have convinced us, could be easily raised in many parts of
Great Britain, where good dry land and a superfluous popula-
tion exist together. On the moderate calculation of 10 Ibs. per
acre, that quantity would only require 4 or 5000 acres of land,
and from 40 to 50,000 people. The employment would be
given to such persons as are not calculated for common agri-
cultural labour, and at a time when labour is wanted, namely,
between hay-time and harvest.—Trans. Soc. Arts, xl. 9.

9. British Indigo.—A discovery has been recently made,
which promises the most impertant consequences in a commer-
cial and agricultural point of view. About two years ago, 280
acres of land near Flint, in Wales, were planted with the com-
mon hollyhock, or rose-mallow, with the view of converting it
into hemp or flax. In the process of manufacture it was dis-
covered that this plant yields a beautiful blue dye, equal in
beauty and permanence to the best indigo,—_New Monthly Mag.
ix. 22.

We should be glad to have this confirmed.

10. Preservation of Grain, §c., from Mice.—Mr. Macdonald,
of Sealpa, in the Hebrides, having some years ago suffered con-
siderably by mice; put at the bottom, near the centre, and at
the top of each stack, or mow, as it was raised, three or four
stalks of wild mint, with the leaves on, gathered near a brook,
in a neighbouring field, and never after had any of his grain
consumed. He then tried the same experiment with his cheese
and other articles kept in ‘store, and often injured by mice ; and

Mechanical Sevence. 141

with equal effect, by laying a few leaves, green or dry, on the
article to be preserved. — Phil. Mag.

11. Preservation of Turnips.—Messts. Staines and. Cowley
preserve turnips during the winter for cattle-feeding, by cutting
off the tops, taking especial care not to injure the crowns,
and then piling them up methodically on straw into a heap,
covered exteriorly with straw. In this way they were found to
keep in a perfectly sound state during the winter, and to be
excellent food for cattle. —Trans. Soc. Arts, xl. 29.

12. Yeast.—The following methods of making yeast for
bread are easy and expeditious. Boil one pound of good
flour, a quarter of a pound of brown sugar, and a little salt,
in two gallons of water for an hour ; when milk-warm, bottle it
and cork it close; it will be fit for use in 24 hours. One pint
of it will make 18lb. of bread.—To a pound of mashed potatoes
(mealy ones are best), add two ounces of brown sugar and two
spoonfuls of common yeast, the potatoes first to be pulped
through a cullender, and mixed with warm water to a proper
consistence. A pound of potatoes will make a quart of good
yeast. Keep it moderately warm while fermenting. This
recipe is in substance from Dr. Hunter, who observes that
yeast so made will keep well. No sugar is used by bakers
when adding the pulp of potatoes to their rising.— Yorkshire
Gazette. .

13. Prevention of Dry Rot.—From an observation of the
power of perfumes in preventing mouldiness, Dr. Mac Culloch
was led to make some trials on wood, with a view to the pre-
vention of dry rot. The results were favourable, but Dr. M.,
not having power to resume the experiments, recommends
them to other persons. A cheap odorous oil is the substance
required.

14. Paste.—Dr. Mac Culloch, in a paper on the power of
perfumes in preventing mouldiness, gives the following direc-
tions for the preparation of a paste, which, as it will keep any
length of time, and is always ready for use, may be of great
service to mineralogists and others. ‘* That which I have
long used in this manner is made of flour in the usual way,
but rather thick, with a proportion of brown sugar, and a small
quantity of corrosive sublimate. The use of the sugar is to
keep it flexible, so as to prevent its scaling off from smooth

142 Miscellaneous Intelligence.

surfaces; and, that of the corrosive sublimate, independently
of preserving it from insects, is an effectual check against its
fermentation. This salt, however, does not prevent the form-
ation of mouldiness; but, as a drop or two of the essential
oils above-mentioned, (lavender, peppermint, anise, bergamot,
&c.,) is a complete security against this, all the causes of de-
struction are effectually guarded against. Paste made in this
manner and exposed to the air, dries without change to a state
resembling horn, so that it may at any time be wetted again,
and applied to use. When kept in a close covered pot, it
may be preserved in a state for use at all times.”—Edin.
Jour. vili. 35.

15. Improved Glaze for Red Ware.—The common red ware
much used in the manufacture of cooking-vessels for the lower
class of people, is generally glazed either with litharge, or the
potter’s lead ore. This glaze is objectionable, not only be-
cause it cracks when the vessels are heated and cooled, but
also from its being soluble in vinegar, acid juices, and animal
fat, and producing very deleterious effects. Mr. Meigh of
Shelton, Staffordshire, has been rewarded by the Society of
Arts for the discovery of a glaze, having none of these bad pro-
perties. Red marl is first ground in water until it forms a
creamy mixture ; the ware, previously well dried but not burnt,
is then immersed in it, by which the superficial pores are filled
up. Being again well dried, it is dipped in the glaze, which
consists of one part Cornish granite, chiefly felspar, one part
glass, one part black oxide of manganese, ground in water to
the consistency of cream: The ware is then dried and fired in
the usual way. If an opaque white glaze is required, the man-
ganese is to be omitted.

Mr. Meigh has also manufactured an improved common
ware from a mixture of four parts common marl, one part of
red marl, and one part of brick clay. It is harder, more com-
pact, and less porous than the common red ware, and when
combined with the above glaze, produces vessels very supe-
rior for those uses to which the red ware is applicd.—T7ans.
Soc. Arts, xl. 45.

16. Soldering Sheet Iron—Sheet iron may be soldered by
means of filings of soft cast-iron applied with borax, deprived
of its water of crystallization and sal ammoniac. Tubes of
sheet iron have been constructed at Birmingham lately by means

Mechanical Science. 143

of a process of this kind, which, according to Mr. Perkins and
Mr. Gill, is to be practised in the following manner :—The
borax is to be dried in a crucible, not till it fuzes, but till it
forms a white crust; then powdered and mixed with the iron
filings: the joint is to be made bright and moistened with a
solution of the sal ammoniac; then the mixture is to be made
into a thick paste with water, and placed along the inside of
the joint, and the whole heated over a clear fire till the cast-
iron fuzes.—Tech. Rep, iii. 110.

17. New Form of the Voltaic Apparatus.—Mr. Pepys has
constructed, at the London Institution, a single coil of copper
and zine plate, consisting of two sheets of the metals, each
fifty feet long by two feet broad, having therefore a surface of
200 square feet; they are wound round a wooden centre, and
kept apart by pieces of hair-line, interposed at intervals be-
tween the plates. This voltaic coil is suspended by a rope,
and counterpoise over a tub of dilute acid, into which it is
plunged when used.

It gives not the slightest electrical indications to the electro-
meter ; indeed, its electricity is of such low intensity that well-
burned charcoal acts as an insulator to it; nor does the quan-
tity of electricity appear considerable, for it with difficulty
ignites one inch of platinum wire of =; inch diameter. When,
however, the poles are connected by a copper wire 4 inch dia~
meter and 8 inches long, it becomes hot, and is rendered most
powerfully magnetic, and the instrument is admirably adapted
. for all electro-magnetic experiments, Dr. Wollaston’s well-
known and curious arrangement of a single pair of plates, may
justly be called a Calorimotor ; and to Mr. Pepys’s coil we may
apply the term Magnetomotor.

18. Patent Portable Static Lamp.—A lamp under this name
has just been perfected by Mr. Parker, of Argyll-street. Its
chief merit is, that the oil is raised to the burning height with-
out springs, valves, or screws, and in a manner not liable to get
out of, repair. To render its principle and construction intelligible
the following short account of the ingenious method by which
Mr. Parker has effected his object, will probably be sufficient ;
in our next Number we shall describe it more accurately with
the aid of a plate.

A cylindrical vessel, open at top, 338; inches diameter, and

144 Miscellaneous Inteliigence.

3 inches high, contains the oil; im its centre is affixed a strong
iron trod, upon which the upper part of the lamp, hereafter to
be described, moves.

Another cylindrical vessel, open at top, 349. diameter, and 7
inches high, surrounds the oil vessel, leaving a space of 42; of an
inch between the two vessels. These vessels are then united at
bottom, and made air-tight, and the =4; space filled with mercury.

Another cylindrical vessel (called the plunging cylinder, be-
cause it plunges into the mercury in the ;% space), closed at
top, and open at bottom (3,2, diameter, and 3 inches high), is
firmly attached to the connecting tube and burner of the lamp,
the tube ascending to the required height of the light, and de-
scending to the lower level of this plunging vessel. This tube
moves up and down the centre iron rod on points, or pins, to
prevent friction or capillary attraction.

The oil-vessel being filled with oil, and the -@; space with
mercury, it is evident the plunging vessel, and oil-tube attached
thereto, entering the mercury and oil at the same time, in the
manner of a gasometer, the air contained in the plunging vessel
cannot escape, and the whole weight of the plunging vessel
(which is loaded to raise the oil the required height,) presses
upon the oil, through the elastic medium of air, and forces the
oil up the centre tube to the adjusted height. This action
continues until all the oil is consumed.

The advantages of this lamp are, that it burns till all the oil
is consumed.

That the oil and weight being in the base, it is not liable to
be overthrown, nor can any oil be spilt.

That it is as perfectly shadowless as a gas-light, and capable
of as much beauty of form.

That there being neither valve, spring, nor screw, it is not
liable to be out of repair, and is easily managed by servants,
the oil being poured into an open vessel, instead of a small
aperture. The mercury is never removed.

That being made of iron, it is not the least acted upon by oil.
It may also be mentioned, that the oil tubes clean themselves
every time the lamp is charged with oil.

That, independent of less first cost than other lamps of equal
appearance, it is economical in other respects. No light is
wasted, as in the French, or even the Sinumbra lamps, for
though in the latter the shadow projected from the ring reser-
voir is overcome, it is only by calling in aid the rays of light

Chemical Science. — 145

from other parts of the flame, while those striking against the
ring reservoir are lost for the purpose of illumination.

II]. CHeEmicat SCIENCE.

1. On the Action of Heat and Pressure on certain Fluids:
By M. le Baron Cagniard de la Tour.—It is known, that by
means of Papin’s digester, the temperature of many fluids may

be raised much above their ordinary boiling points; and one
is led to suppose, that the internal pressure augmenting with
the temperature, would prove an obstacle to the total evapo-
ration of the fluid, especially if the space left above the fluid is
not of a certain extent.

Reflecting on this subject, it occurred to me that there was
necessarily a limit to the dilatation of a volatile fluid, beyond
which it would become vapour, notwithstanding the pressure, if
the capacity of the vessel would permit the liquid matter to
extend to its maximum of dilatation.

To ascertain this point, a certain quantity of alcohol, sp. gr.
.837, and a sphere of silex, were put into a small digester, made
out of the thick end of a musket barrel, the liquid occupying the
third of the capacity. Having observed the noise produced by
the sphere, when rolled in the cold. apparatus, it was gradually
heated until a point was reached, when the ball seemed to
bound from end to end of the digester, as if no liquid had been
present. This effect, easily distinguished by holding the end
of the handle to the ear, ceased on cooling the apparatus, and
was reproduced on re-heating it.

The same experiment made with water, succeeded only im-
perfectly, because of the high temperature required interfering
with the tightness of the instrument. But sulphuric ether and
naphtha presented the same results as alcohol.

That the phenomena might be observed with more facility,
the liquids were introduced into small tubes of glass, and her-
metically sealed. A handle of glass was attached to each tube.
A tube was two-fifths filled with alcohol, and then slowly and
carefully heated ; as the fluid dilated, its mobility increased,
and, when its volume was nearly doubled, it completely disap~
peared, and became a vapour so transparent, that the tube ap-
peared quite empty. On leaving it to cool for a moment, a
very thick cloud formed in its interior, and the liquor returned
to its first state. A second tube, nearly half occupied by the

146 Miscellaneous Intelligence.

same fluid, gave a similar result ; but a third, containing rather
more than half, burst.

Similar experiments with naphtha, sp. gr..807, and with ether,
gave similar results. Ether required less space than naphtha,
and naphtha less than alcohol, to become vapour; appearing to
indicate, that the more a body is already dilated, the less ad-
ditional volume does it acquire before it attains its maximum of
expansion.

In all the previous experiments, the air had been expelled
from the tubes; but repeated with others in which the air was
left, the results were similar, and the phenomena more readily
observed, from the absence of ebullition.

A last trial was made with water in a tube of glass, about
one-third of its capacity being occupied by the fluid. This
tube lost its transparency, and broke a few instants after. It
appears, that by a high temperature, water is able to decompose
glass, by separating the alkali; leading us to suppose, that
other interesting chemical results may be obtained, by multi-
plying the applications of this process of decomposition.

On carefully watching the tubes in which air had been left, it
was remarked, that those in which the fluid had not space for
the maximum of dilatation preceding the conversion into va-
pour, did not always break as soon as the liquid appeared to
fill the whole space; and that the explosion was the more tardy,
as the excess of liquid above that required to fill the space was
less. May not, then, the consequence be inferred, that liquids
but little compressible at low temperatures, become much more
so at high temperatures? And this is more likely in the case in
question, where the fluid is just on the point of becoming elas-
tic, under a pressure which, by theory, appears to be equal to
many hundred atmospheres.

It is difficult to believe, that a little tube of glass, about +18;
of an inch internal diameter, and 54; of an inch thick, could re-
sist so considerable a force: perhaps it may be supposed, that
the molecules of an elastic fluid, and particularly of vapour,
are susceptible, under a certain compression and heat, of con-
tracting a change of state comparable to that of a half fusion,
and capable of facilitating a reduction of volume greater than
that due to the true pressure.

Whilst waiting for new experiments on this subject, it ap-
pears that the following conclusions will include what has al-
ready been described :—1. That alcohol, naphtha, and sulphurie

Chemical Science. 147

ether, submitted to heat and pressure, are converted into
vapour, in a space a little more than double that of each liquid.
2. That an augmentation of pressure, occasioned by the presence
of air, caused no obstacle to the evaporation of the liquid in
the same space, but only rendered the dilation of the liquid
more regular and observable. 3. That water, though suscepti-
ble of being reduced into very compressed vapour, has not yet
been submitted to perfect experiments, because of the imperfect
closing of the digester at high temperatures, and also because of
its action on glass tubes.— Annales de Chim. xxi. 127.

In a supplement to the above Mémoire, M. Cagniard de la
Tour states the results of experiments made to ascertain the
pressure produced in the experiments described. The process
adopted was to bend a tube into a syphon, place ether in one
leg, and separate it from the other containing air, by mercury ;
both legs being sealed, the apparatus was heated, and when the
ether became vapour, the diminution in the bulk of the air
marked. In the present experiment, 528 parts became 14, a
result which was thrice obtained. Ether, therefore, is suscep-
tible of being converted into vapour in a space less than twice
its original volume, and in this state it exerts a pressure of be
tween 37 and 38 atmospheres.

When alcohol, sp. gr. 837, was used, 476 parts of air be-
came 4; and from an observation of the volume, it was ascer-
tained that alcohol may be reduced into vapour, in a space
rather less than thrice its original volume, and that it then
exerts a pressure of 119 atmospheres.

The temperature at which these effects took place was ascer-
tained, by repeating the experiments in an oil bath. The ether
required a temperature of 320°, F.; alcohol, that of 405°, F.

In the Mémoire it was announced, that water heated in tubes
of glass altered the transparency, so as to prevent observation
of what passed within; but M. Cagniard de la Tour found that a
small quantity of carbonate of soda prevented, in a great measure,
this effect. He was enabled therefore, though only with difficulty,
from the frequent rupture of the glass tubes, to ascertain, that
at a temperature but little removed from that of melting zinc,
water could be converted into vapour, in a space nearly four
times that of its original volume.—Annales de Chim. xxi. 178.

2. Berthier on Sulphurets produced from Sulphates.—The
experiments made by M. Berthier had for their object the de-
Vou. XV. L ,

148 Miscellaneous Intelligence.

termination of the composition and nature of certain sulphurets,
such as those of the alkaline and earthy metals. ‘‘ They have,”
says M. Berthier, “ given me the means of resolving the
question, till now undecided, whether the alkalies and alkaline
earths are or are not in the metallic state in the sulphurets pre-
pared by fire. They are so simple, that one is astonished they
have not been made before ; and it may be seen they conduct,
in the most evident and direct manner, to the knowledge of the
nature of the alkalies and alkaline earths.”

The method by which M. Berthier reduces sulphates to sul-
phurets is not by directly mixing them with powdered charcoal,
and heating them ina crucible, but by placing them in the
centre of a crucible, thickly lined with charcoal, covering them
with the same substance, and after having luted on a cover,
heating the whole ina furnace. In this way the sulphates are
reduced by cementation, as it were, the time required being
proportioned to the temperature, the fusibility of the sulphurets,
and the volume of the substance. All are reducible at a white
heat, and, where the sulphuret is fusible, very quickly; but
when it is infusible, it remains interposed between the charcoal
and the sulphate, and the action is slower. An ounce of sul-
phate may in'this case require above two hours. In this way not
only are pure sulphurets obtained, but the result may be col-
lected without the smallest loss, its weight ascertained, and the
weight of oxygen evolved accurately estimated.

If a sulphate of baryta, strontia, or lime, be thus reduced to
a sulphuret, and weighed, the loss will be found to equal ex-
actly the quantity of oxygen contained in the base and acid.
If the sulphuret be dissolved in muriatic acid, nothing will be
liberated but pure sulphuretted hydrogen; no sulphur will be
set free, nor any acid, containing sulphur and oxygen, formed ;
finally, if a portion of the sulphuret be heated in a crucible of
silver, with nitre equal to three or four times its weight, the sul-
phate regenerated will correspond with the quantity of sulphu-
ret employed, and will contain neither acid nor base in excess.
These three experiments prove that the sulphuret produced
contains no oxygen, and, consequently, that the base is in the
metallic state ; and if, in addition to these means of analysis,
the experiment be made in close vessels, and the gaseous pro-
ducts collected and analyzed, it will be found that the loss of
weight sustained by the sulphate is exactly made up by the
quantity of oxygen given off.

Chemical Science. 149

The following are some of the results obtained by this mode
of operation. Sulphuret of Barium.—White and light grey,
slightly aggregated, and composed of crystalline grains. It
dissolved completely in water, without colouring it, the solution
giving, with muriatic acid, sulphuretted hydrogen, without pro-
ducing any turbidness. It was scarcely affected by heat alone;
but detonated with nitre, and raised to a white heat, afterwards
diffused through water, and saturated with muriatic acid, it
was found that the fluid contained no sulphuric acid, and but a
very slight trace of barytes. Hence the re-conversion into sul-
phate had been complete. 120 parts of sulphate of baryta, in
becoming sulphuret, lost 34 parts. This sulphuret is composed
of

BAUM | 2 >. LOO
Sulphur . . . 24,47

Sulphuret of Stronttum.—White, granulated, aggregated, and
friable; 20 parts sulphate lost 7.2 parts by reduction into sul-
phuret ; its composition is,

Strontium . . . . 100
Sulphur! siccs5 6 Dis 0186.6

Sulphuret of Calccum.—White and opaque, retaining the form
of the gypsum used, soluble in water, &c., like the compound of
barium ; 20 parts of sulphate of lime from Puy, lost of water
and oxygen 9.24. The sulphuret is composed of

AUCUEN ta a yo gt SED
Mulpngr ots Coy hee

Sulphurets of Potassium and Sodiwm.—Mamumilated, crystal-
line, translucid, and ofa fine flesh-red colour. These dissolved
in water, with great heat, are very difficult to roast ; they do
not evolve sulphur, but slowly become sulphates. When they
have become mixed with charcoal in the crucible, they inflame
upon being moistened, Sulphuret of potassium consists of,

Potassium . . . . 100

Sulphur. . 2... «41.06
Sulphuret of sodium. of,

Sodium). 4e baw eae LOU

Sulpnae Peers. se Moe!

Sulphuret of Maynesium.—10 of sulphate of magnesia re-
cently calcined, gave 3.95, of a white friable residue, which,
| a

150 Miscellaneous Intelligence.

boiled in water, gave a solution of hydro-sulphuret of magnesia,

-and pure magnesia remained; 1.5, acted on by water, gave a
solution contain 0.18 magnesia; 1 heated with nitre, &c., gave
0.85 sulphate of baryta, equivalent to 0.12 sulphur. The sul-
phuret of magnesia is composed therefore of

Magnesium . 0.072 0.094
Sulphur . . 0.120\or by tery 018
Magnesia . . 0.780) 0.786

972 1.000

To accord with the theory, the loss should have been 0.608,
instead of 0.605.

Sulphuret of Copper.—10 of dry sulphate gave 4.76 of sul-
phuret, mixed with a few grains of metallic copper. M. Ber-
thier ascertained that there was no action between this sulphuret
and metallic copper; therefore, probably no sulphuret con-
taining less sulphur exists.

Sulphuret of Zinc.—30 parts of sulphate gave, in one experi-
ment, 4.5 parts; in another, 13.2. The sulphuret produced
was of a flaxen colour, and in crystalline grains, composing a
friable mass. When analyzed, it proved to be of the same com-
position as blende, z.e.,

LAG ns so Soe setae te ALOU
Sulphur. .....° -50

In the experiments on zinc an excessive loss occurred, which,
after some trials, M. Berthier traced to the action of the char-
coal on the sulphuret. He found that a piece of native blende
thus heated, lost in two hours 5, of its weight, and if powdered
and mixed with charcoal, the whole would have been dissipated
in a short time. This action is attributed to the affinity of the
carbon for the sulphur; and it was ascertained, by heating a
mixture of charcoal and sulphuret of antimony, that an analo-
gous action took place, for the gaseous products being made to
passthrough a condenser,a ‘considerable quantity of sulphuret of
carbon was procured. Sulphuret of iron, of copper, and many
other sulphurets, diminish in weight, when heated with char-
coal, from the same cause.

Sulphate of Lead, with charcoal, gives a sub-sulphuret of
lead, which, by further heat, is partly volatilized, and partly
decomposed.

Sulphuret of Manganese is easily obtained. It is pulverulent,

Chemical Science. 151

black, and without lustre, dissolving in muriatic acid, and
liberating pure sulphuretted hydrogen. It is composed of
Manganese . . 100
Sulphur . . . 56.32
M. Berthier then enters into an account of various double
sulphurets, which, though highly interesting, we have not room
to notice at present.—Journal des Mines, vii. 421.

3. On Compounds of Nickel, by J. L. Lassaigne.—The object
of M. Lassaigne was to ascertain directly the representative
number of nickel, by experiments on its compounds. They
were made, we presume, with perfectly pure nickel, obtained by
M. Laugier’s process ; for the principal reason for their being
undertaken, was the discovery by M. Laugier, that the nickel,
generally considered as pure, contained a large proportion of
cobalt.

Protoxide of Nickel—A given weight of pure nickel was
dissolved in pure nitric acid, evaporated to dryness, and de-
composed by heat. It was of a gray colour, soluble in acids,
precipitated by alkalis as a hydrate, &c. Composition,

TERE e eta cat, sah
Oxygen yee Baiae sae

Deutoxide of Nickel. — Obtained by diffusing hydrate
of nickel in water, and passing a current of chlorine through
it; one part is dissolved, and the other converted into peroxide
of nickel. It is of a brilliant black colour; heated, it loses
oxygen and becomes protoxide. Acids dissolve it, liberating
oxygen, except muriatic acid, which produces chlorine with it,
Its composition was ascertained by its loss of weight when
heated, and appeared to be,

Nickel . . 100
Oxygen. . 39,44

é or rather by theory be

Sulphuret of .Nickel.—Prepared directly from its elements,
It is of a yellow colour like iron pyrites, and very brittle.
Insoluble in sulphuric and muriatic acid, but decomposed by
nitro-muriatic acid. It was analyzed by calcination with nitre,
and the sulphuric acid determined by barytes. It was com-
posed of

Nicke} ‘nee $100
Sulphur . aes by theory 9 49

152 Miscellaneous Intelligence. |

Chloride of Nickel.—Prepared by evaporating the muriate
of nickel to dryness. ‘The dry product is the protochloride of
nickel ; is of a yellow-green colour, and is composed of

Wickel) °°.) ‘eudqilB0
Chlorine,» pa) aioe oe) 90
When the proto-chloride of nickel is calcined in a retort,
one portion of an olive-green colour remains in the bottom of
the vessel, whilst another sublimes and crystallizes in small
light brilliant plates of a gold yellow colour. These are to be
considered as a deuto-chloride of nickel, and are insoluble in
water, and indecomposable by sulphuric acid. They are
formed of
Niekels oor Syyh00 0
Chlorine’. 200% PY theory of ke
Iodide of Nickel—Obtained by heating nickel and iodine
in atube. It is a brown substance ; fusible; soluble in water,
colouring it of a light-green ; and composed of
Nickel . . 100% 100
lodine °’.'”’'’gao f' bY: theory of 1312.8
Ann, de Chim. xxi. 255.

4. On Indigo, Cerulin, Phenicin, §c., by Mr. Crum.—The
following is a very compressed account of some points on the
chemical history of indigo, for which science is principally in-
debted to Mr. Crum. We have taken them from that gentle-
man’s paper, published in the Annals of Philosophy.

Indigo may be obtained by agitating the yellow liquid of the
dyer’s blue vat in contact with air, and digesting the precipitate
in dilute muriatic acid, and afterwards in alcohol, To obtain
it perfectly pure it should be sublimed, which is best done by
placing eight or ten grains of it in the cover of a platinum
crucible, putting another cover over it, and then heating the
lower by a lamp; a sublimate rises which is pure indigo. The
apparatus must not be cooled during the sublimation. Sub-
limed indigo crystallizes in long flat needles, splitting into
quadrangular prisms. Looked at in heaps, the colour is rich
chestnut-brown; at a particular angle, they have an intense
copper-colour, but thin plates when looked at directly before
the light, are seen to be transparent, and of a beautiful blue
colour. Indigo sublimes at 550°, and it melts and also de-
composes very nearly at the same temperature. Its specific
gravity is 1.35. It sublimes in open vessels leaving no residuum,

Chemical Science. 153

but in close vessels a quantity of charcoal is deposited. Vo-
latile and fixed oils dissolve small portions of it.

Being analyzed by oxide of copper, its composition appeared
to be

l atomazote .. . 175 ...- 10.77

2 oxygen. . 2.00 . = - 12.3]

4 -—hydrogen. . 0.50 . « - 3.08

16 carbon’. © «12.00 sescome 73.84
16.25 100

Excepting a minute proportion of lime, precipitated indigo
gave the same result.

When indigo is digested in sulphuric acid, it is con-
verted into a very peculiar blue substance, to which Mr. Crum
has given the name of cerulin. The mixture requires much
water to dissolve it, and its filtered solution is precipitated by
potash. This precipitate is as plentiful before one-fourth of
the acid is saturated as when the whole is neutralized ; it is
also produced by sulphate of potash. When thrown on a
filter and washed, it entirely dissolved in pure water, but the
presence of any salt of potash rendered it insoluble.

Some of the precipitate, washed first by weak solution of
acetate of potash, and afterwards by alcohol, was burnt in a
crucible; a large quantity of ashes was left, consisting of neutral
sulphate of potash, with a little iron. Another portion of the
substance, prepared even with muriatic acid and muriate of
potash, gave sulphate of potash as before. Hence it appears
to be a combination of cerulin with sulphate of potash, and
may be called ceruleo-sulphate of potash. The salt forms more
than a fourth of its weight.

A ceruleo-sulphate of soda may also be formed ; it is more
soluble than the compound with potash. Ceruleo-sulphate of
ammonia is still more soluble, and is decomposed by potash or
soda. The compound with barytes is extremely insoluble.
An abundant blue precipitate is formed by muriate of barytes
in solutions of ceruleo-sulphate of potash, containing so little
sulphuric acid as not to be troubled in the slightest degree, if
the cerulin be previously destroyed by nitric acid,

Ceruleo-sulphate of potash when moistened is almost black,
when dry of a deep copper-colour—one part dissolves in 140
of water, forming an intense blue solution, which is precipitated
by every thing but distilled water. Luminous objects seen
through it appear of a rich scarlet-colour, but a single drop of

154 Miscellaneous Intelligence.

nitrate or sulphate of copper added, makes them appear blue:
Acid again makes them appear red.

With regard to the phenomena attending the production of
cerulin, when indigo is put into sulphuric acid, it is dissolved,
and a yellow fluid results, rendered blue by water. The blue
precipitated is indigo unchanged ; but if the yellow solution be
left undiluted, it becomes blue of itself, and in less than 24
hours the whole becomes cerulin. Any production of sulphu-
rous acid which may be observed, is due to impurities ; for when
pure, there is no action of that kind by the application of boiling-
water heat for some hours. On analyzing the ceruleo-sulphate
of potash by oxide of copper, cerulin was found to be composed
of l;atom/ azote)! ve. o1:75 esc. 8:43 P

6 oxygen. . 6.00 . . 28.92
8 ——-hydrogen . 1.00 . . 4.82
16 —— carbon . . 12.00 . . 57.83

20.75 100.00

By stopping the action of the sulphuric acid on the indigo,
before the formation of cerulin is complete, Mr. Crum obtained
what he conceives to be a new and peculiar body, to which he
has given the name of pheneczn. As soon as the mixture of
acid and indige is become of a bottle-green colour, it is to be
diluted with a large quantity of water, filtered and washed.
The blue washings which will ultimately be obtained are to be
precipitated by muriate of potash, and phenicin will be pre-
cipitated, of a beautiful reddish purple colour. It is to be fil-
tered and washed, till the washing precipitates red with nitrate
of silver; it may then be dried.

Phenicin forms blue solutions, both in water and alcohol,
but all salts precipitate it purple. It appears to be easily
changed into cerulin, by the mere action of water. From the
mean of several experiments, 100 of indigo produces 120 of
phenicin. Its composition is considered as being,

l atom azote . . 1.75 . . 9.46
4 oxygen. . 4.00 . . 21:62
6 —— hydrogen. 0.75 . . 4.05
16 —— carbon. . 12.00 . . 64.87

18.5 100.00

Alcohol remarkably modifies the action of sulphuric acid
upon indigo. Three parts of ,alcohol, sp. gr. 0.84, with. two

Chemical Science. 155

parts of acid, dissolves indigo without rendering it yellow, and
it may remain thus any length of time, without change.

5. Robiquet on Volatile Oil of Bitter Almonds.—This, oil,
when exposed to the air for a few minutes, becomes a crystal-
line mass, and loses its odour. M. Vogel, who first remarked
the fact, found that the odour was restored by dissolving the
crystals in hydro-sulphuret of ammonia. He attributed the
loss of odour and change of state to oxidation, and the restora-
tion of odour by the hydro-sulphuret, as due to a deoxidation
effected by that substance. M. Robiquet, on the contrary, led
by his own particular views of aroma, (see Vol. x. p. 109,)
attributed the loss of odour to the loss of ammonia ; and its re=
storation, to the ammonia added in the hydro-sulphuret.

With a view to illustrate the true cause of the phenomena,
M. Robiquet lately experimented on this subject. He found,
that instead of taking place in a few minutes, the crystalliza-
tion sometimes required several days; and, in consequence, he
was led to distil the oil, collecting the results in different por-
tions. In this way he found, that the first portions underwent
no change in contact with the air, but that the last portions
crystallized immediately on exposure to it, or to oxygen, with
absorption of the gas; whilst in nitrogen, hydrogen, carbonic
acid, or in the torricellian vacuum, no change took place.

By further examination, it was ascertained that the most
volatile portion of the oil contained nitrogen, as an element ;
for when boiled with solution of potash, it gave prussiate of
potash, and when heated with oxide of copper, nitrogen. The
less yolatile and crystallizable parts contained no nitrogen; and
when pure and in crystals, it was found that the odour of bitter
almonds was not given to them by hydro-sulphuret of ammo-
nia. The crystalline matter appears to be an acid substance ;
it reddens litmus; it is soluble in boiling water, and crystal-
lizes by cooling ; it is fusible, and readily volatile ; it unites to
alkalies, and appears to have no analogy with the oil frem
which it is derived.

These two parts of the oil of bitter almonds, when examined
as to their action on the animal economy, were found entirely
different ; the more volatile was excessively poisonous, but the
crystallizable matter was quite inert. M. Robiquet, in con-
sidering the nature of the principle containing nitrogen, is in-
clined to consider it as different from prussic acid, though

156 Miscellaneous Intelligence.

readily convertible into it. Fixed alkalies, for instance, exert
no action on it when cold, though at high temperatures they
readily form prussiates, and a crystalline substance very dif-
ferent from that already described. Another acid, and a resi-
nous matter, is also found at the same time.

M. Robiquet, in a note, considers the oil of the cherry laurel
as identical with that of bitter almonds.— Ann. de Chim. xxi. 250.

6. Action of Animal Charcoal in the refining of Sugar.—
M. Payen proves, in a memoir which has been rewarded by the
Pharmaceutical Society of Paris, 1st, That the decolouring
power of charcoal, in general, depends on its state of division ;
2d, That in the various charcoals, the carbonaceous matter,
only, acts on the colouring matters, combining with and precipi-
tating them; 3d, That in the application of charcoal to the re-
fining of sugar, it acts also on the extractive matters, for it sin-
gularly favours the crystallizati@n ; 4th, That according to the
above principles, the decolouring action of charcoals may be so
modified, as to make the most inert become the most active ;
5th, That the distinction between animal and vegetable char-
coals is improper, and that for it may be substituted that of
dull and brilliant charcoals; 6th, That of the substances pre-
gent in charcoal besides carbon, and particularly in animal
charcoal, those which favour the decolouring action have an
influence relative only to the carbon: they serve as auxiliaries
to it, by isolating its particles, and presenting them more freely
to the action of the colouring matter; 7th, That animal char-
coal, besides its decolouring power, has the property of taking
lime in solution from water and syrup. 8th, That neither ve-
getables, or other charcoals besides animal, have the power of
taking lime from water or syrup; 9th, That by the aid of an
instrument, which he proposes to call a decolorimeter, it will
be easy to appreciate exactly the decolouring power of ‘all
kinds of charcoal.— Annales de Chim. xxi. 215.

7. Refining or toughening of Copper.—When the smelter has
reduced his copper perfectly, it is in what is called a dry state.
It is brittle, of a deep red colour inclining to purple, an open
¢rain, and a crystalline structure. A process is then. resorted
to, called the poling, the object being to render the copper
tough and malleable. The metal, whilst in fusion in the re-
verberatory furnace, has its surface covered with charcoal, and

Chemical Science. 157

a pole, generally of birch, is thrust into it, and retained there ;
a violent ebullition takes place, which is continued until the
refiner perceives, by the assays he takes, that the grain is closed
and silky, and the metal of a light red colour. The copper is
then laded out into cakes.

The whole of this operation requires great attention. The
surface must be covered with charcoal, or the metal will go
back. On the contrary, if the poling be continued too long,
the colour becomes a light yellowish red, and the malleability
is injured. In that case, by drawing the charcoal off, and ex-
posing the metal to air, it is restored to a proper state.

Some curious questions arise with regard to the copper in
these different states. Is the dry copper combined with oxy-
gen? or is there any oxide of copper, either diffused through or
combined with the metal? Is the overpoled copper a com-
pound with carbon? Is the malleable metal, copper, in a pure
state? or is the effect of the pole merely mechanical? It may
be remarked, that dry copper has an extraordinary action on
the iron tools used; they become bright, like iron in a smith’s
forge, and are consumed much more rapidly than when the
copper is in a malleable state; also, that when copper is gone
too far, it oxidizes slowly ; on the surface it remains bright, and
more than usually splendent, reflecting, like a mirror, every
brick in the roof; thus supporting the idea, that carbon is
united with it, and, by combining with the oxygen of the air,
prevents the formation of oxide.—See Mr. Vivian’s paper, Ann,
Pha, v. 121.

On this head we may refer also to Mr. Lucas’s experiments
on silver. See Journal, Vol. viii. p. 168.

8. Action of Ammoniacal Gas on Copper.—The following
experiments are by Signor Fusinieri:—Dry iron and copper
wires were introduced into dry barometer tubes, into which dry
ammontacal gas was then introduced over mercury. Then in-
clining the tubes, the part containing the metal was heated bya
lamp. After a while, the iron became ofa brownish colour, and
the volume of the gas increased, from the decomposition of the
ammonia into its elements; but no other results were obtained.

On the contrary, the copper wire gave evident signs of com-
bination. The bulk of the gas diminished, notwithstanding a
partial decomposition, and consequent expansion. The copper
became of a paler colour, and a sublimate rose, and attached

158 Miscellaneous Intelligence.

itself to the tube, having the same colour as the copper, and, in
one place,-even its metallic splendour. The heat was continued
for three quarters of an hour, during which time the matter in
the tube remained unchanged. A copper wire thus heated be-
ing withdrawn from the tube, and moistened, became slightly
blue after some time, and the sublimate in the tube underwent
the same change slowly in the air. Another tube, with its
copper contents left exposed to the air alone, became brown
and blue in different parts.

Sig. Fusinieri deduces from these results, that dry ammoniacal
gas combines with copper, by the aid of heat, the compound
being volatile, and retains the colours of the metal, though it
be more pale. Also, that the formation happens without the
production of colours ; and also, that this dry ammoniuret of
copper has the power of decomposing water, of oxydizing the
metal, and then of forming the common blue ammoniuret.—
Giornale di Fisica.

These conclusions do not come with much force to our minds;
but we insert the experiment at this time, because chemists
are anxiously looking to nitrogen and its compounds for some
results illustrative of its nature.—Ep.

9. Estimation of Carbonic Acid in Mineral Waters.—It is
frequently an object in the analysis of mineral waters, to ascer-
tain the quantity of carbonic acid in them; and for this, seve-
ral processes are recommended. Among others, is that of
boiling the water in a retort or flask, and passing the gas libe-
rated from it through a solution of muriate of lime, or barytes
to which ammonia has been added ; the quantity of carbonate
thrown down being the indication of the quantity of carbonic
acid from the water.

Dr. Vogel of Munich, however, finds the process very faulty,
from the circumstance of its not indicating small quantities.
Three or four cubic inches of carbonic acid gas, added to one
ounce of ammonia, and this to a solution of one part of muriate
of baryta in nine of water, produced no change. Precipitation
would begin only on adding more carbonic acid, or on boiling,
An ammoniacal muriate of baryta, added to carbonic acid gas,
over mercury, caused no precipitation, by the absorption of
the first two or three inches of gas; and when the precipitate,
caused by a further absorption of gas, had been filtered
out from the liquid, more was obtained by -ebullition. Only

Chemical Science. 159

in cases where a great quantity of gas is absorbed by the
ammoniacal solution of baryta or lime, or where the mix-
ture stands for several days, are the carbonates entirely pre-
cipitated.

Even lime water, when the lime is not entirely separated
by carbonic acid, retains some carbonate of lime in solution,
which will be found by heating such lime water to ebullition in
a closed retort, when the carbonate will fall to the bottom ;
and it was ascertained by a comparative experiment, that the
precipitate was not due to the separation of lime from the hot
water, but was really a carbonate of lime.

Though both lime-water and barytes water absorb carbonic
acid, and readily deposit carbonates; yet, when previously
mixed with ammonia, they are not in the least rendered turbid
by a small quantity of carbonic acid gas, and ebullition is re-
quired to perfect the precipitation.

Lime-water acts in the same manner when poured into a
solution of alkaline carbonate of ammonia; the transparency is
slightly clouded, and immediately after restored, and ebulli-
tion is required to obtain a precipitate. If a large proportion
of lime-water be added, a permanent precipitate is obtained.

If, therefore, a muriate of barytes, or lime mixed with am-
monia, be employed to detect carbonic acid, it must be boiled
some time, to throw down the whole of the precipitate; but
Dr. Vogel recommends, as the surest means to pass the gas
through barytic water, and to determine the volume of the
carbonic acid gas, from the weight of the carbonate, when dried.

It is often of importance to obtain the carbonic acid from the
water at the spring head. To do this, we have sometimes
adopted the plan of adding such a quantity of barytes water
to a given volume of the spring water, as to precipitate all the
carbonic acid, and then ascertain the quantity of carbonic acid
in the precipitate in the laboratory, and we know of no objec-
tions to the plan.—Eb.

10. Plumbago in Coal-gas Retorts.—The following descrip-
tion of an artificial plumbago, is by the Rev. J.J. Conybeare ;
he is speaking of the retorts in the Bath gas-works. The
unservicable retorts, on being withdrawn from their beds, are
found lined with a coating of plumbago, averaging the thick-
ness of four inches. This coating is thickest towards the bot-
tom of the retort. The general aspect of the predominant va-

160. Miscellaneous Intelligence.

riety may be thus described: Colour iron-grey, somewhat
lighter than that of native plumbago; texture scaly; structure
mamellated, usually in very close aggregation—some specimens
exhibit this structure on the large scale, but generally it re-
quires the lens to be seen; hardness variable, but always
greater than the best native plumbago—scratches gypsum, but
is scratched by calc spar; lustre of the exterior surface sometimes
very considerable, lustre of the fracture usually but small; the
powder uniformly resembles that of common plumbago, but is
somewhat less brilliant. The quantity of iron in it seldom ap-
peared to amount to 9 per cent. It is hardly fit for finer pur-
poses of art, but it is proposed to use it in diminishing friction,
in making crucibles, furnaces, &c.— Ann. Phil. v. 51.

The artificial production of plumbago is by no means an
unusual event. See p. 321, Vol. IX. of this Journal. In fine,
iron castings where charcoal in fine powder has been used as
the facing, the cast may be observed every where covered with
a thin coat of plumbago.—Ep.

11. Test of the Dryness of Air or Gases.—M. Serullas re-
commends the alloy of bismuth and potassium, obtained by
heating together G60 parts carbonized cream of tartar, 120 of
bismuth, and 1 of nitre, for two hours, as an excellent test of
the dryness of gas in certain circumstances. A small fragment
of the alloy is to be introduced into the gas over mercury, and
the least moisture in it will tarnish the metal immediately.
The alloy is so rich in potassium, that the smallest fragment,
when cut with scissors, scintillates. If a piece be bruised, it
burns, leaving a green oxide.

12. Variation of Thermometers.—Il Signor Bellani refers to
the following experiment as a proof of the changeableness of
a thermometer, with regard to the temperatures it expresses,
and in illustration of the cause of those changes. Take a mer-
curial thermometer, including a range at least from freezing to
boiling water, having degrees of such magnitude, that +1, of a
degree may readily be perceived, and not having been exposed
for some months to a temperature near that of boiling water.
Mark exactly the point at which the mercury stands in thawing
ice, then plunge the bulb in boiling water, and then again
mark the temperature indicated in thawing ice; it will indicate
above a tenth of a degree lower this time than the former.

Chemical Science. 161

The effect is greater the higher the temperature is raised, and
the more rapidly it is done; and M. Bellani attributes it to the
slower contraction of the glass, after having been expanded by
heat, as compared with that of the mercury. He refers to it as
an unavoidable source of error in all delicate thermometrical
operations, as in the barometrical thermometer, &c.

13. Blue Iris Test Colour.—Professor Ormstead of North
Carolina University, recommends the tincture of the petals of
the garden iris, or blue lily, as superior to every other test
liquor known. It is reddened as litmus is, by blowing through
it, or by a stream of carbonic acid gas. It is more convenient
than violets, from the abundance of colouring matter contained
in the petals; and it is said to be superior to red cabbage tinc-
ture, as well for its permanency as its delicacy. Of the former
cause of superiority there may be doubts. This application of
the petals of the blue iris has long been known to us; by rub-
bing them upon paper, we form a very convenient test either
for acids or alkalies.

14. Succinie Acid in Turpentine.—MM. Lecanu and Serbat
have ascertained with certainty the presence of succinic acid in
turpentine. It rises when the oil is distilled, towards the end
of the operation, and has all the properties of true succinic
acid. They have pointed out also, that the presence of acetic
acid takes from succinic acid the power of forming precipitates,
with preparations of iron, copper, lead, or barytes. Neither
will a mixture of acetate and succinate of potash precipitate
these substances; on the contrary, the succinates, when pro-
duced, are soluble without difficulty, in a sufficient quantity of
acetate of potash.— Annales de Chim. xxi. 328.

15. Cinnabar.—M. Kirchoff prepares cinnabar in the follow-
ing manner. Triturate in a porcelain cup with a glass pestle
300 parts of mercury with 68 of sulphur moistened with some
drops of a solution of potash till a black proto-sulphuret is
formed, and then add 160 parts of potash, dissolved in an
equal quantity of water. Heat the vessel containing the mix~
ture over the flame of a candle or lamp, continuing the tritu-
ration without intermission. Add pure water from time to time
as the liquid evaporates, that the substance may be constantly
covered an inch deep. After two hours continued trituration,

162 Miscellaneous Intelligence.

a great part of the liquid being allowed to evaporate, the
mixture begins to change from black to brown, and then
quickly to red. No more water is to be added, but the tritu-
ration is to be continued. The mass will acquire the con-
sistence of a jelly, and the red becomes more and more bril-
liant with great rapidity. When .it has attained its highest
perfection the cup should instantly be removed from the flame,
or the red will quickly change to a dirty brown colour.—Pidl.
Mag.

16. Dobereiner’s Apparatus for making Extracts.—This ap-
paratus serves to extract by means of water, alcohol or ether,
the soluble substances from any substance to be analyzed, in
quantities from 10 up to 200 grains. It is composed of a tube
of glass from 4 to 9 lines in diameter, and from 4 to 9
inches long. The tube is closed below by a cork, to which
is adapted a small tube open at both ends. This, except that
its upper extremity is covered with a piece of muslin, commu-
nicates with the large tube. The substance to be operated
upon is put into the large tube about half filling it, and the
solvent is then put in over it. A small glass bulb propor-
tionate in size to the quantity of solvent used, is then emptied
of air by heating a few drops of alcohol in it, and immediately
attached by a tight cork to the lower end of the small tube.
The whole apparatus is then set aside in a cool place; as the
alcohol vapour condenses, a vacuum is produced, and the pres-~
sure of the air in the large tube forces the fluid through the
substance to be operated upon into the bulb. In a few mi-
nutes the extraction is complete, the bulb is then removed, its
contents taken out, the air init again displaced, and the operation
repeated ; or, if necessary, the fluid is left in contact with the
substance some time before it is made to pass from it into the
bulb.— Bib. Univ. xxi. 188.

17, Heat from Friction of a Solid and Fluid.—It may be
remarked that the rapid rotation of the little mills which com-
plete the attenuation of the liquid mixture for paper before it
passes to the tub, produces in it a very sensible heat not at all.
due to the elevation of the temperature of the wheel itself by
the friction of its axis, for it cannot be perceived by touching
that part, but attributable to the blow of the fans of the wheel.
on the mixture, which they strike with much rapidity and yio-:

Chemical Science. 163

lence. This is the first instance known to us of heat produced
by friction of a solid against a liquid. M. Pictet.—Bxd.
Univ. xxi. 134, y

18. Condensation of Gases into Liquids—In a note annexed
to Mr. Faraday’s paper, (page 74 of this Number,) we have
mentioned the result of some experiments made by him in the
laboratory of the Royal Institution, and which led to obtaining
chlorine and muriatic acid in the liquid form. By pursuing
this mode of experimenting, sulphuretted hydrogen, sulphurous
acid, carbonic acid, cyanogen, euchlorine, and nitrous oxide, have
been also found to assume the liquid form under pressure, and
to appear as limpid and highly mobile fluids. It is probable
that other gases may be condensed by similar means, and that
nitrogen, oxygen, and even hydrogen itself may yield, provided
sufficient pressure can be commanded. Some of Mr. Perkins’s
experiments render it more than probable that atmospheric air
under a pressure of some hundred atmospheres changes its
form ; and it is not unlikely, that some very curious and inte-
resting results may be obtained by the aid of a slight modifi-
cation of the apparatus used by that gentleman in his researches
connected with high pressure steam. ‘

19. Electricity of a Cat.—The electricity excited upon rub-
bing the back of a cat is well known, and that it is rendered
evident by snapping noise and sparks of light. Mr. Glover, in
a letter to the editor of the Philosophical Magazine, describes
so intense an action of this kind, as to.enable the animal to give
a very sensible electrical shock. This effect was obtained at plea-
sure by Mr. Glover, and also by some friends. When the cat was
sitting on the lap of the person, if the left hand were placed under
the throat with the middle finger and the thumb gently pressing
the bones of the animal’s shoulder, and the right hand were pass-
ed along the back, shocks were felt in the left hand; and when
the right hand was placed under the throat, whilst the left hand
rubbed the back, the shocks were felt in the right hand. When
the atmosphere has been favourable, and the cat had lain some
time before the fire, the experiment always succeeded.—Piil.
Mag. \x. 467.

20. Magnetism of Solar Rays.—The Royal Academy of
Sciences, at Lyons, haye offered a prize of 300 francs, for an
Vou, XV. M

164 Miscellaneous Intelligence.

éssay on the following subject. To shew by decisive experi-
ments if the violet ray of the solar spectrum possesses the
virtue of communicating magnetism to the unmagnetized needle
of steel; if this virtue belongs to it, to the exclusion of the
other coloured rays—and, in short, if this species of communi-
cated magnetism, attributed to the violet light, is real or illusory-
It is stated, that Professor Configliachi, found magnetism was
communicated by every other ray of light— Mémoires to be sent
to MM. Mollet and Dumas, before July, 1823.

21. Inflammation of Powder under Water.—M. Serullas has
given the following directions for the preparation of a very ful-
minating charcoal, by means of which, gunpowder may very
readily be inflamed under water.

Carefully powder together 100 parts of tartar emetic, and 3
parts of lamp black, or common charcoal. Prepare some cruci-
bles, capable each of holding about 2 ounces of the mixture, by
rubbing them within with powdered charcoal to prevent the
adherence of the carbonaceous mass left after calcination. Fill
them about three-fourths with the mixture, then put in a stratum
of powdered charcoal, and lute on a cover; after 3 hours’ calci-
nation in a good reverberatory furnace, the crucibles are to be
removed, and left for six or seven hours to cool, that the air,
which always enters, may have time to burn the surface of the
fulminating mass, for otherwise, if withdrawn too soon, explo-
sion always takes place. At the end of that time great care is
to be taken in transferring the mass in the crucible as rapidly
as possible into a vessel with a large aperture, which can be
perfectly closed. In time, the mass divides of itself into frag-
ments, and may be preserved for years.

When the calcination has been thus performed, the produce
is excessively fulminating ; soas, without compression or confine-
ment, to give, on the contact of water, a detonation like that of
a powerful musket.

The following mixture will also produce an equally fulminat-
ing charcoal; 100 parts of antimony, 75 of cream of tartar, 12
of lamp black, well powdered and mixed together.

The experiment of firing gunpowder under water by means
of these substances, was made in the foilowing manner :—half
an ounce of gunpowder was put into a strong glass tube, closed
at one end; a piece of fulminating charcoal, about the size of
a péa, was placed upon it, and immediately the orifice of the

Natural History. 165

tube closed by a prepared cork, which had a small hole through
it, closed by fat lute. The tube was then retained by weights
at a depth of between two and three feet beneath the water, and
then, by means of a steel wire fixed to a long rod, the lute was
perforated, and water admitted. The powder immediately in-
flamed, and a weight of above 2lb. was thrown out of the vessel
containing the water.—Aznales de Chim. xxi. 197.

Ill. Narvurat History.

1. On the Ascent of Clouds in the Atmosphere, by M. Fresnel.—
Among the causes which most effectually contribute to the ascent
of clouds in the atmosphere, there is one to which little attention
has been given, but without which it appears impossible to give
a satisfactory explanation of the phenomenon. It is indepen-
dent of the constitution of the globules of water, or vesicular
vapour composing the cloud ; and is equally applicable to one
formed of an assemblage of delicate crystals, such as may
actually exist in the high regions of the atmosphere.

Air, as wellas other colourless gases, permits the solar rays
to pass without being heated by them; and to heat fhem, the
contact of a solid or liquid body, heated by the same ray, is re-
quired. Consider, then, the case of a cloud formed of minute
globules of water, or very fine crystals of snow: from the ex-
treme division of the water, a very multiplied contact with the
air is obtained, and the water being susceptible of an increase
of temperature from the solar and terrestrial rays, the air
within the cloud, and near to its surface, will become more
dilated than the neighbouring air, and consequently lighter.
It equally results from the hypothesis, on the extreme division
of the matter of the cloud, that the particles which compose it
may be very near each other, so as to leave but small intervals,
and nevertheless be very much smaller than the iftervals; so
that the whole weight of the water in the cloud should be but a
a small fraction of the weight of the air containing it, and so
small, that the difference between the density of the air in
the cloud and the neighbouring air should more than com-
pensate it. When the weight of the water and air contain-
ing it is less than that of an equal bulk of the surrounding air,
it will ascend until it arrives at a region where these two weights
are equal; and this height will depend on the fineness of the
particles of the cloud, and the intervals which separate them.

M 2

~

¥66 Miscellaneous Intelligence.

The hot and dilated air contained in those intervals not being
hermetically retained, will gradually escape; but this renewal
of the internal air must take place very slowly, so that the
temperature of the cloud will always be above that of the neigh-
bouring air, and this ascending current of air, by the mere
friction of its parts against the particles of the cloud, will tend
to raise it, and that with the more energy as it is more rapid.

During the night the cloud is deprived of the solar rays, and
its temperature should diminish, but it will still receive warm
rays from the earth ; and if it is very thick, or of great depth,
its temperature can diminish only slowly. Experience. proves
directly, that clouds during the night are warmer than the air
surrounding them, inasmuch as. they send us more calorific rays.’
Supposing even that the difference of temperature was much
less by night than by day, still. the clouds should descend with:
extreme slowness after sunset, because of their immense extent
of surface, relative to their weight: it is a cause which, without
referring to their elevation, must contribute powerfully to. their.
suspension, and the rise of the sun would again elevate them to
their former altitude, if winds or other atmospheric phenomena
have not ¢hanged the conditions of equilibrium. Such an effect
may be produced by an augmentation or diminution of the par-
ticles of the cloud, or the intervals between them; and the,
changes in the temperature of the surrounding air, alter the
conditions of equilibrium, and consequently the height to which
the cloud may rises There are without doubt, also, other causes
which contribute to the elevation and suspension of clouds, as
the ascending currents spoken of by M. Gay Lussac (vol. xiv.
p. 446). Ido not purpose to consider all the causes, but merely
to indicate that which appears to me the most important.—
Bib. Univ. xxi. 255.

2. Aérolite of Epinal—Vhe stone which fell in the neigh-
bourhood of Epinal, about three quarters of a league from La
Baffe, on the 15th of last September, has been examined chemi-
cally by M. Vauquelin. Like most aérolites, it was covered by a
fused black coat. Within, it was of a gray colour, with many
metallic points. Ground in a mortar, a great number of parti-
cles of metallic iron were separated, leaving an impalpable
earthy powder.

From the quantity of metallic iron existing in this stone, it was
difficult to obtain a portion for analysis, which should give the

Natural History. 167

4rue composition of the whole: 4 grammes, (61.8 gr.)-were taken
and gave,

Billige. i 5 Teeemee habred
Oxide ofiron, . . . 2.51
Sulphur, racine Mle eS,
Oxide of chrome . . .01
Oxide of nickel, . . .02
IAEBEDHE,. Teo ae ety ss eke
Lime and potassa. . .50

4.70

The 2.51 oxide of iron correspond to 1.76 metallic iron; but
the 0.09 of sulphur would require 0.16 of iron to form the proto-
sulphuret ; and if, beside this, 0.18 be subtracted for the 0.25 of
oxide of iron, which in the analysis was found united to the
chromic acid, there will remain 1.42 of metallic iron, containing
only nickel and manganese for the 4 of aérolite. The quantity
of nickel was so small, that cobalt could not be looked for in it,
but M. Vauquelin thinks it probable that it was present.—
Ann. de Chim. xxi. 324.

‘3. Large Meteor.—A magnificent meteor was seen by Mr.
Davenport, on the 28th October last, at about half-past five in
the evening. It was seen from Silver-hill, on the Hastings
road, and appeared as a luminous ball, of full one-third of the
apparent diameter of the moon, giving a remarkably bright and
white light. Its direction was north-east, its height above the
horizon about 22°. It passed horizontally to the west, over an
are of about 20°, occupying about 8} seconds of time. Mr.
Davenport is anxious to know whether other persons have seen
the same meteor; and if so, from whence, and in what direc-
tion.— Ann. Phil.

4. Fall of Rain in the Tropics. — Professor Silliman gives the
following statement, on the authority of M. Rousuis, captain of
a vessel. It is contained in a letter from Cayenne. ‘‘ You will
perhaps learn, with no inconsiderable interest, the following
meteorological fact, the authenticity of which I am able to cer-
tify. From the Ist to the 24th of January (1820), there fell
upon the island of Cayenne, twelve feet seven inches of water.
This observation was made by a person of the highest veracity,
and I assured myself, by exposing a vessel in the middle of my
yard, that there fell in the city ten and a quarter inches of water,

168 Miscellaneous Intelligence.

between eight in the evening and six in the morning of the 14th
and 15th of that month.”

5. New Comet.—A luminous appearance was observed in the
heavens, on the night of Wednesday, Noy. 13, at the distance
of about a degree and a half from Cor Caroli, which very much
resembled a small comet. It was viewed distinctly for ten
minutes, from the hills in the neighbourhood of East Grinstead,
but a veil of cloud then hid it, and it has not since been seen.
—New Monthly Mag. ix. 33.

6. Analysis of Uranite.—This mineral has been analyzed, both
by Mr. Gregor and Berzelius ; the latter philosopher found it to
be “ a compound of oxide of uranium with lime and water; in
fact, a true salt, with a base of lime, in which the oxide acts as
an acid ;”” and he considers the Cornish variety as containing
an accidental admixture of arseniate of copper.

Mr. Phillips has lately re-analyzed this mineral, and very unex-
pectedly finds it to contain phosphoric acid ; indeed, to be a
phosphate. A specimen from Cornwall gave, ;

Milica. e Sil aR 5
Phosphoric nana del regi 28:
Oxide of uranium . . 60.0
Oxide ofcopper . . 9.0
Mater We ed lew te | et eeee
100

or, neglecting the silica,
Phosphate of uranium 73.2

Phosphate of Capps? . 12.3
Water. «. . 14.5

Ann. Phil., v. 59.

7. Native Phosphate of Alumina.—A substance has lately
~been placed in the hands of M. Vauquelin for analysis, which
proved to be phosphate of alumina. It was brought by M.
Debassyns from the Quartier Saint Paul, Isle Bourbon, being
found in a volcanic cavern, occurring in a large basin, formed by
the river Saint Gilles, and known in the country by the name
of the Blue Basin.

No one had before entered the cavern, which is very deep
and irregular, and covered with stalactites. After a few steps,
there are found considerable portions of the white earth, de-

Natural History. 169

posited against the sides; and it occurs in proceeding, until
replaced by a black earth, which, in certain places, forms the
entire bottom of the cavern, and preserves the form of the blocks
of lava, which appear to have fallen from the roof.

The white earth has a slight tint of yellow, no consistence,
and is very light; it feels unctuous, and adheres to the tongue.
On analysis, it proved to be a subphosphate of alumina, mixed
with a small quantity of phosphate of ammonia.

1.400 Alumina.

0.914 Phosphoric acid.

0.094 Ammonia.
Water.

The black matter found in the cavern was almost entirely
animal ; five parts gave only 0.35 of ashes when burnt, which
were phosphate and carbonate of lime, with a little iron. In
the same cavern were found heaps of bones, which, from a
specimen brought home, appeared very ancient. The specimen
was very fragile, and was covered with crystals, in brilliant
needles, which proved to be phosphate of lime. M. Vauquelin
suggests that this animal matter was the source of the phospho-
ric acid, found united with the alumina.

8. Crystallized Stalactitic Quartz.—The stalactites which
covered the roof of this cavern, when examined by M. Vauquelin,
proved to be quartz. They were found in concentric layers, and
offered all the physical characters of calcareous stalactites,
except the hardness. The composition was, ’

lex ee eu ee ROO
Oxide iron . . .060
Lime. agen" 31
W ater ee et Se
Loss 3 2 me. ONS

1.100
Ann. de Chim. xxi. 188,

9. Ammonia in Lava.—Professor Gmelin, of Tubingen, is said
to have discovered, in clink-stone lava, ammonia, which is dis-
engaged by distillation. He also found it in columnar basalt.

10. Muriate of Ammonia from Coal Strata.—There is a coal-
mine near Saint Etienne, which, having been fired, through in-

170 Miscellaneous Intelligence.

advertence, has now been burning for several years. Besides the
usual products arising from the combustion of coal, it exhales
a great quantity of muriate of ammonia. Fumes arise from the
burning surface of the ground, which condense into the solid
salt, and in dry weather the whole surface is covered with it.
Some very fine specimens were found within an inhabited house ;
and so abundant was the production in the years 1818 and
1819, that many pieces were separated from the walls, weighing
above 2 lbs. avoirdupois. The ruins of this house, treated in
the large way for the separation of the salt from them, gave
such results as would have proved lucrative, if pursued.

Inreferring to the probable source of this salt, it is remarked,
that the water of all the wells on this coal stratum contain, among
other salts, a very notable quantity of earthy muriates.—dnn.
de Chim. xxi. 158.

11. Waters of Carlsbad.—The waters of Carlsbad, taken from
the principal source, have been analyzed lately by M. Berzelius,
who finds many substances in them not hitherto suspected.
The following are his most extraordinary results: 1000 parts
of water gave,

Sulphate of soda. . . . . 258714
Carbonate of soda .. . . . 1.25200

Muriate of soda. . . . . . 1.04893
Carbonate of lime . . . . . 0.31219
Fluate; dfjlime ys: -cdnye: ora cigs hee ics 410-0033

Phosphate oflime . . . . . 0.00019
Carbonate of strontian. . . . 0.00097

Carbonate of magnesia. . . . 0.18221
Phosphate of alumina . . . . 0.00034

Carbonate ofiron . .. . . 0.00424
Carbonate of manganese . . . traces
HRCA c. | sccaeinbnkh yssetialws, voslastn @0e Od

5.46656

Ann. de Chim. xxi. 248.

12. On the Flowers of the Meadow Saffron, by Mr. Frost.—
This last autumn, I made several preparations of the meadow
saffron flower (viz., a vinegar tincture and wine), which have
subsequently been administered by several able physicians with
whom I am acquainted ; and they have informed me that the
preparations of the flowers operate more uniformly and certainly

Natural History. 171

than those of the bulb and seeds. It has long been a matter
of great doubt as to what the basis of the celebrated Eau Medi-
ciale really is, but it is now pretty certain that a tincture of
the flowers of colchicum autumnale constitutes that noted nos-
trum.

13. Return of Captain Laing from the Solima Territory, in
Africa. We are happy to have it in our power to state, that Capt.
Laing, of the Royal African Colonial Regiment, to whom the
readers of the Quarterly Journal are indebted for the narrative
of Mahomed Misrah’s Journey from Egypt to the Western
Coast of Africa, published in our XXVIIth Number, has re-
turned to Sierra Leone, from a residence of some months in
the Solima territory, to which he proceeded in April last, by per-
mission of Sir Charles Macarthy, and on the invitation of the
King.

The country, thus visited for the first time by an European,
possesses a peculiar geographical interest, as the source of the
mysterious Niger: we understand that the elevation above the
sea, as well as the latitude and longitude of the hill of Soma,
from whence it derives its origin, haye been satisfactorily as-
certained by Captain Laing, and that his observations and
journal are on their way to England. )

The information which Captain Laing has obtained, cannot
fail in other respects also to be both important and interesting,
as the Solimas are a numerous and powerful nation of the in-
terior, of whom scarcely more than the name was known until
three years ago, when an army of 10,000 men appeared in the
Mandingo country, to terminate a dispute between two chiefs
of that nation, the weaker of whom had appealed to the King
of Solima; it was upon this occasion that Captain (then Lieute-
nant) Laing was despatched by the government of Sierra Leone
on a mission to Yaradee, brother of the king, and commanding
the army, whose confidence and good opinion he succeeded in
gaining, which led to the present visit.

We are happy to learn that Captain Laing’s health has been
improved by travelling in the interior, which has hitherto been
deemed so dangerous to Europeans; and that his further expe-
rience has confirmed the belief which he expressed in the com-
munication to which we have referred, that no material diffi-
culty would be experienced in the route from Sierra Leone,
through Sankara, to the Niger at Nafi.

172 ’ Miscellaneous Intelligence.

14. Hauy’s Collection of Minerals.—The very complete mi-
neral collection of the celebrated M. Hauy will shortly be sold
at Paris by public auction. The professor, in his lifetime, re-
fused for it an offer of 600,000 francs (24,000/. sterling).

15. Organic Remains.—The skeleton of a rhinoceros was
discovered a short time ago, by some miners in search of lead
ore, ninety feet below the surface of the earth, in the neigh-
bourhood of Wirksworth, Derbyshire. The bones are in a per-
fect state, and the enamel of the teeth uninjured. We believe
Mr. Buckland has seen these remains.

16. Change of Water at Falls—In an account of the great
water-falls of Renah, on the rivers Mohanuddy, Behur, and
Jouse, in the province of Gund-wana, the writer describes the
following phenomenon. The water, when it reaches the bottom
of the fall, assumes a dirty green appearance, similar to salt
water near the shore, and the taste becomes bad and sour. It
is not the great depth of the pools into which the water falls
that causes the colour; for that which issues out of the basins,
and runs over rocks so shallow as not to come much above the
ancle, has the same green aspect. The same effect is produced
at each of the falls. —Edinburgh Journal, viii. 37.

17. New Species of Fungi.—Messrs. Pictet and Decandolle,
whilst examining a paper manufactory, remarked the produc-
tion of a great variety of fungi in the mass of rags placed to-
gether for the purpose of fermentation, previous to their being
beaten into pulp. They were of various forms, sizes, and co-
lours, and many of them appeared to M. Decandolle, who
made a large collection of them, to be of undescribed species.
It may be necessary to observe, that the fermentation was going
on in a place under ground, and it is well known how much
plants alter their external appearance when vegetating in such
situations.

18. Preservation of Echini, Asteria, Crabs, §c.—It is a
great object to preserve specimens of these species of animals
in a natural history collection, so that they shall not fall to
pieces. Colonel Mathieu, who has made a fine collection from
the Isle of France, endeavoured to find some means of so dry-
ing the mucilaginous or membranous part, which serves as an

Natural History. 173

articulation between the joints, as to prevent that separation
which so frequently takes place ;. and he found the best to be
the application of dilute lime-water, before drying. Echini
were first emptied, and then the animal put into lime-water for

. 12 hours, taken out and dried in the shade, and put in the
same water for two hours, and then dried, the spines being pre-
served in their place by cotton.

Asterize were put alive into lime-water, and treated as the
echini. Such as were fleshy had the flesh first removed. There
are some so delicate as not to be able to bear immersion until
dead; when alive, even fresh water will cause them to separate
into many pieces.

With the crustaceous animals, as the crab, the head is first
removed and dried in the shade, then the body and limbs emp-
tied as much as possible. The specimen is then placed in
lime-water five or six hours, and dried in the shade thrice suc-
cessively. When dry, and having but little odour, the head is
replaced, and the whole preserved in the shade. The colours
are very little injured Y the operation.—Journ. de Physique,
xcy. 155.

19. African Geography.—Mr. Bowdich has made arrange-
ments for the speedy publication of a sketch of the Portuguese
establishments in Congo, Angola, and Benguela, with some
account of the modern discoveries of the Portuguese in the
interior of Angola and Mozambique, with a map of the coast
and interior.

174

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+--+ Aepug ~~ + Supuopy a a - = Aepsanyy,
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THE

QUARTERLY JOURNAL,

July, 1823.

Art. I. An Account of the Eruption of Vesuvius, in
October, 1822. By G. Poutert Scrorn, Esq.

[With a Plate. ]
Naples, March 19, 1823.

Since the end of the last century the great crater of
Vesuvius has been gradually filled by the accumulation both
of lava boiling up from below, and of scoriz falling from the
explosions of the different minor mouths which were formed at
intervals during the last twenty years on its bottom and sides.
When I visited the mountain in 1818-19, this great crater was
almost entirely obliterated;—no regular concavity appeared,
but in its place a rough and rocky plain, rising into two rude
eminences at the northern and southern extremities, covered
with blocks of lava and scoriz, and cut up by numerous fissures,
from many of which clouds of vapours were evolved in consi-
derable quantities. By the eruption of last October this state
of things has been totally changed. The explosions which
then, during the space of more than twenty days, were inces-
santly and with terrific violence taking place from the focus of
the volcano, broke up and threw out all this accumulated
mass, and ended by completely gutting the mountain, so as ta
leave an immense gulf or chasm of an irregular and some-
what elliptical shape, about three miles in circumference if mea-
sured along the very sinuous and irregular line of its extreme
Vou, XV. N

176 Account of the Eruption of Vesuvius,

margin, but somewhat less than three-quarters of a mile in
its longest diameter; which is directed from N.E. to N.W.
Its depth is perhaps rather above 700 feet, but decreases daily
by the dilapidation of the sides.

The enormous quantity of matter which, previously to the
eruption, occupied this space, was thrown out in fragments of
every size, varying from blocks of some tons in weight, to
the most impalpable powder. The greater part, however, cer-
tainly issued from the mountain in the latter form, having un-
dergone a complete trituration during the process of continued
and repeated ejection. After the first four days of the eruption,
the substances thrown out were solely pulverulent, becoming
finer, lighter, and of a lighter colour every day. These ashes
as they are called, (certainly without much propriety, being
only pulverized lava,) rose from the crater in dense and prodi-
gious clouds, to a height, at one time, of nearly two miles, and
were thence borne away on the winds to great distances, the
heavier particles falling in showers from the line of clouds
thus formed along its whole track, The yast crater, which was
emptied by this violent process, presents an aspect very differ-
ent from that which is usually assumed by the concayities of
voleanic cones. These generally appear in the regular form of
an inyerted cone, whose sides slope at about the same angle
to the horizon as those of the outer cone, This is, indeed, in-
variably the case with every cone which is produced by a
single volcanic eruption, That of Vesuyius, however, resulting
from the accumulated products of, perhaps, many hundred
eruptions, must consist of numerous beds of scoria and frag-
mentary lava, alternating with the strata of lava rock, which
at interyals have been poured in fiery torrents down its outer
slope, and congealing there, have remained like so many mas-
sive ribs, to give strength and solidity to the structure.
Through this succession of beds, then, has the present crater
been forcibly hollowed out by the explosive energy of the
volcano. It appears as a tremendous abyss of enormous pro-
portions, surrounded by craggy precipices that rise almost ver-
tically from the rude heaps of fallea fragments which form its

tn October, 1822. 177

floor, and conceal the volcanic orifice. The extreme periphery
of the crater in some parts juts over these precipices, so that
on attaining its margin you look directly down into the gaping
cayity. In others, a steep inclined plane, of no great width,
interyenes between the edge of the cliffs and the acute ridge in
which the interior and exterior slopes terminate. On this
inner and shelving surface it is necessary on many points to
pass while making the tour of the crater; in general, it affords
a firm and safe footing, being formed of the fine sand which
was the last product of the late eruption, and into which the
foot sinks to some depth; but, when the surface of this slope
is hardened by frost into an unyielding and slippery crust,
(which was the case on the morning of my first visit,) the
passage is extremely perilous. The danger is, in fact, the same
on the outer as the inner slope, since a slide or a false step
would be probably fatal on either side ; but the idea of falling
into the crater is more appalling than that of rolling down the
exterior of the cone.

The cliffs that encircle the great cayily by no means follow
any regularity of curye, but project or recede in salient and
retiring angles. Their abrupt faces which are rocky, jagged,
and unpicturesque in the extreme, present sections of many
currents of lava, some of which are of great thickness and
extent, lying one aboye the other in a direction more or less
approaching to the horizontal. Most of them offer a columnar
division of the most marked and decisive kind. Some are
almost as regularly prismatic as any ranges of the older basalts.
In some the spheroidal concretionary structure on a large scale
is equally conspicuous. Between the currents of lava are inter-
posed shapeless beds of volcanic conglomerate, consisting of
fragments of all sizes heaped together in chaotic confusion.
These, as well as the beds of lava, are occasionally intersected
by vertical or nearly yertical dikes, similar to those of Somima
above the Atrio di Cavallo.

The whole scene presents, perhaps, an unparalleled example
of the horribly sublime. The deep and yawning gulf, on the
yerge of which the spectator must hang to observe its terrors ;

N 2

178 Account of the Eruption of Vesuvius,

the rugged and fractured cliffs that frown ‘around it; their
gloomy colouring, and calcined aspect; the dense sulphureous
vapours that rise from fissures on every side; together with
the thundering echoes which almost at every minute proclaim
the fall of some fragments detached from the sides into the
abyss below; create a sense of grandeur and awe, too impres=
sive to be easily effaced. The great crater of tna, even if
larger, which I much doubt, is in my opinion by no means so
striking. Time and the meteoric agents have considerably
softened the features of this last scene, while there is a vivid
and terrible freshness in the crater of Vesuvius ; the wound
which has been torn through the bowels of the mountain is as
yet raw and unhealed; and the imagination forcibly recurs to
that powerful demonstration of the energies of Nature in all
their violence, which so lately was exhibited from this spot,
and which is liable to re-commence at the instant.

Viewed from a distance, the crater still appears to emit at
all times a considerable quantity bf smoke, which increases
prodigiously during stormy weather. However, on attain-
ing the summit of the cone, it becomes evident that little or no
vapour rises from the concealed vent of ‘the volcanic focus at
the bottom of the basin. Thick clouds, on the contrary, take
their rise just within the margin of the crater, evolving them-
selves from fissures in the broken extremities of those currents
of lava which were produced by the last eruption, and which
without doubt are still at an extremely high temperature, pro-
bably, indeed, incandescent and liquid at their centre, since
paper and wood take fire immediately on being thrust’ to a
certain depth in their clefts. The slowness with which lava
conducts caloric is well known. It is, therefore, to be ex-
pected, that the fall of rain in any quantity would propor-
tionately increase the activity of these vapours, which are
almost solely aqueous. The moisture deposited on the sur-
face of the recent lava currents, that nearly envelop the
whole cone, percolating to the interior, becomes converted
into steam, and forces its way through the longitudinal rents
or channels that occur in every lava current, and particularly

an October, 1822. 179

in. those whose course has been rapid, until it issues at last in
clouds from the ragged edges of the stratum at the margin of
_ the great opening.

. The great cone of Vesuvius has lost. considerably in height.
A very large excrescence on the south side, resulting from the
accumulated ejections of three or four minor mouths, and forming
its most elevated point, fell in during one of the most violent con=
vulsions of the last eruption; so that the opposite or north side
of the crater is now the highest peak of the cone. By baro-
metrical measurement I find it to be 3829 feet above the sea.
The lowest part of the ridge, forming the periphery of the
crater, is on the east side above Pompeia, and 3346 feet in
height. The absolute elevation of the mountain has been di-
minished by rather more than 100. feet, while the bulk of the
cone has been greatly increased by the lava torrents that
clothe its sides, as well as the still greater mass of ejected
fragments.

Amongst the latter products are some few pieces-of granite,
and of crystalline limestone with mica, Vesuvian, §c., pre-
cisely similar to the erratic blocks which so frequently occur in
the conglomerates of the Monte Somma; and hence it appears
that the explosions of this recent eruption have shattered and
blown into the air a portion of the strata belonging to that
older volcano. But.by far the greater number of ejected blocks,
with which the slopes of the cone of Vesuvius have been
strewed by the late eruption, consist of leucitic lava, and are
evidently fragments forcibly torn off from those currents of an
earlier date, whose sections are seen in the broken and preci-
pitous cliffs of the crater. Many of these lavas have a highly
torrefied aspect. They have obviously undergone a recoction,
if the expression is allowable, either from having been exposed
for ages to the heat, which, in the centre of the cone, from
whence they were probably torn, must have been always
intense, or during.the period of rejection by the present erup-
tion, having perhaps more than once been yomited forth and
thrown back again into the burning gulf, before their final
lgnding on the exterior of the cone. These fragments exhibit

180 Account of the Eription of Vesuvius,

a more or less pearly lustre, apparently in proportion to the
greater or less degree of torrefaction they have enduted. The
fusion of the leucites seems to be the cause of this appearance.
In some specimens this process has been carried to such ex-
tremity that a portion of the lava has run into a black glass;
which fairly merits the name of Leucitic Obsidian. In colour,
fracture, and transparency, this substance resembles the common
trachytic obsidian of Lipari, but differs from it in melting
before the blowpipe into a black glass, while the obsidian of
Lipari is well known to produce one of a greyish-white
colour.

But this is not the only alteration produced on these errati¢
blocks of lava, by their re-exposure to the intense action of the
volcanic furnace. In some cellular specimens, the cavities are
thickly lined with crystals of specular iron, and of various
other minerals, hitherto undescribed, if not unknown. Amongst
these, the most remarkable are delicate capillary crystals, which
are found by the lens to be hexagonal prisms, hollow within,
formed by the lateral junction of six long rectangular plates.
They are either white, or of a light flesh-red colour, and oceupy
cavities which seem to have been produced by the total or par-
tial disappearance of the larger crystals of leucite. Acicular
radiated mesotype occurs in the same manner; as well as bril-
liant crystals in rhomboidal dodecahedrons, of a dark-green
colour. These new crystalline minerals, thus, to all appear-
ance, created out of the elements of a lava composed simply of
leucite and augite, during its re-exposure, under peculiar cir-
cumstances, to the action of volcanic heat, may be expected to
throw a useful light on the origin of the numerous and proble-
matic minerals occurring in those erratic blocks of crystalline
limestone, &c. §c., of the Monte Somma, which appear to
have undergone a similar process during the activity of that
ancient and enormous volcano; and a stronger degree of pro-
bability is thus added to the opinion, by which these blocks of
limestone, with their accompanying mica, augite, garnet, vesu-
vian, nepheline, §c. §¢., are supposed to be, not unaltered
fragments of primitive rocks, but portions, perhaps, of the cal-

tn October, 1822. 18]

careous or other strata which once covered the site of Vesu-
vius, variously affected by repeated and continued exposure
to the influence of the mysterious and ever-varying pheno-
mena which take place in the fiery depths of the volcanic
laboratory.

In a chemical light, the eruption of last October distin-
guished itself from all preceding ones by the excessive abun-
dance of sulphur deposited by the vapours evolved from the
lava it produced. The various chemical products of these
fumarole have been collected and analyzed, with great care, by
Messrs. Monticelli and Covelli, who have been closely occu-
pied, since the date of the eruption, in preparing for the press
a descriptive work on the subject, which will probably be out
in a few weeks, and, I have no doubt, will prove extremely
interesting. If I can discover any method of forwarding it to
England, I will despatch it as soon as published. In the
mean time, perhaps, these brief remarks may help to gratify the
curiosity of the readers of this Journal.

Perhaps, it is worth while to mention, that the appearance of
the actual crater of Vesuvius offers a complete confirmation of
the opinion I was led to adopt in France, as to the identity of
the circus or upper basin of the Dordogne, in the Mont D’or,
with the principal crater of that extinct volcano.

Were the fires of Vesuvius to be in turn extinguished, and
its activity cease from this moment, (a circumstance by no
means impossible,) a few centuries would probably see the in-
terior of the crater laid open by a valley, through which the
waters accumulating at its bottom, would discharge themselves
into the sea; and in this event, the resemblance to the upper
circus of the valley of the Dordogne, would be most strikingly
exact. The lofty and precipitous rocks encircling each basin
offer the same general characters ; equally ragged, shattered,
and calcined, they are composed alike of conglomerate beds,
alternating with strata of lava, prismatic or not, and intersected
occasionally by vertical dikes. From the margin of these
cliffs, in either case, the outer flanks of the cone shelve down-

182 Account of the Eruption of Vesuvius,

wards, with a steep and regular slope, to the base of the
mountain.

Another interesting parallel may also be drawn between the
large accumulations of volcanic sand (or ashes) and frag-
mentary lava, (commonly called lapillo,) washed down from
the sides of Vesuvius by the rains, which fell with great vio-
lence during the late eruption, and those large deposits of
tufaceous conglomerates, in the volcanic country of France,
to which I assigned, upon the spot, a similar origin. Nothing
could be more confirmatory of the justness of that hypothesis,
or more clearly illustrate the mode of formation of such rocks,
than the phenomena which took place on all sides of Vesuvius,
a few days after the great crisis of the eruption in October last.
The fine impalpable sand thrown out from the crater for many
days together, had covered the surface of the mountain to the
depth of from one to five feet; and necessarily impeded what-
ever rain fell upon this space, from draining off, as usual,
through the porous and leose matters which compose the sides
of the volcano. In this state of things, on the 27th October,
the clouds, which had long gathered in dense masses round
and above the cone, began to discharge their contents in pro-
digious quantities ; and, in consequence, torrents of sand, mixed
with water, appearing like liquid mud, swept, with terrible
impetuosity, down the slopes, tearing them up in their passage,
hurrying along fragments and blocks of lava, of great size,
(some even from 40 to 50 feet in girth,) and depositing heaps
of alluvium on the sides and at the foot of the mountain. The
damage occasioned by these “‘lave d’acqua,” or “ di fango,”
as they are called in the language of the country, was far
greater than what was suffered from the “lave d? fuoco.” The
latter only destroyed a few acres of wood and vineyard, but
by the former a much larger space of cultivated soil was de-
vastated, walls were overthrown, houses and streets filled with
sand and stones, and some lives even lost, from the suddenness
of their descent.

There can be no doubt, that a great portion of the tufa

in October, 1822. 183

strata, under which Pompeia and Herculaneum lie buried, were
deposited by alluvial torrents of this nature; and I make no
question, but that parallel phenomena, on a larger scale, pro-
duced those massive formations of tufas and breccias, which
shew themselves in such abundance around and upon the ex-
tinct colossal voleanoes of central France.

P.S.—I open my letter to say, that accounts have just arrived from Sicily,
of an earthquake having done great damage in that island. Palermo has
been shaken dreadfully, about thirty lives lost, and houses injured to an
extent of loss equal to half a million sterling, it is said. Messina and
Catania have suffered much less. It is difficult to say whether this cala-
mity has any connexion with the eruption of Vesuvius last year, or with
the dreadfully stormy weather we have had since. It is a very unusual
phenomenon at Palermo,

References to Plate.

(A) Lowest lip of the crater immediately above Bosco Ire Case, and
facing Pompeia. In this direction the side of the cone was split open
during the eruption, and a large crevice formed, which threw up lava,
scoriz, and sand, on five or six points.

(B) Punta del Palo, the highest peak of the actual cone, and fronting the
. North.

Arr. I1.—On Mineral Veins. By J. Mac Cuuiocn,
M.D., F.R.S. Communicated by the Author.

Tx a practical view, there is not a subject in the whole range
of geology of greater importance, than that which relates to the
history of mineral veins; and, accordingly, there are few that
have been more examined. Neither is it by practical miners
alone that this subject has been investigated; since theoretical
geologists have not only compared, and reasoned on, the facts
which these persons have brought to light, but have themselves,
on many occasions, undertaken the labour of personal exami-
nation. It is, nevertheless, true, that, excepting in a very few
particular cases, confined to narrow districts, which have been
the subjects of great experience, no general rules haye been
established, from which any useful practical results have been
deduced, or which are capable of laying the foundation of a
rational theory respecting their formation and origin. We can
neither conjecture, a priori, in what districts or in what rocks

184 Dr. Mac Culloch on Mineral Veins.

they are to be expected, what courses they hold, what various
forms and accidents they may display, nor what substances they
contain. Where little information can be procured, much will
not be expected.

Although mineral veins may exist without necessarily con-
taining metallic substances ; yet, as the general characters of
these are the same, they do not require to be distinguished
here, farther than as may relate to the nature of their contents.
Minerals of many kinds are also occasionally found in reposi-
tories which cannot properly be called veins, and metallic sub-
stances are not even limited to these. To describe these latter
cases first, will be to clear the present inquiry of circumstances
which would otherwise encumber it.

Many metallic minerals are found scattered among the con-
stituents of the compound rocks, so as almost to form parts of
their composition. ‘Thus, oxydulous iron is found in granite,
gneiss, sandstone, and trap; molybdena in gneiss; and iron
pyrites in slate, shale, and limestone. They sometimes, also,
occur independently; neither forming part of the composition
of rocks, nor incladed in distinct repositories. In this way,
pyrites is found in innumerable situations ; copper in the trap
rocks; and oxydulous iron in the products of volcanic fire.
Lastly, some of these are found accumulated in such quantities
in particular spots, still without forming veins, as to admit of
being wrought for economical purposes. Cobalt thus occurs
in sandstone, as does copper. Iron, in the form of ironstone
and bog-ore, is known to abound in beds; the first among the
coal strata, and the latter in alluvial soils. Thus, also, tin
and gold are found among alluvial soils; but, in these cases,
the origin of the metals is, without difficulty, inferred to be in
distant veins. It is likewise understood, that manganese oc-
curs in the form of beds; as has also been said to happen with
respect to mercury, copper, lead, and silver; but it is necese
sary to remember, that veins, holding a course parallel to the
including strata, have sometimes been mistaken for beds,

Such parallel veins are, however, sometimes distinguished
by the term of flat, while the intersecting ones are called rake

Dr. Mac Culloch on Mineral Veins. 185

veins: but, as no useful information is communicated by the
adoption of provincial and technical terms, they are here avoid-
ed. Geology can gain nothing by being further encumbered
with terms that only produce an unnecessary jargon; and it is
the duty of every one to avoid sullying the English tongue. To
shroud in the mystic terms of any science or art, whether in
the phraseology of miners or the symbols of algebra, that which
can be expressed in ordinary language, is either the result of a
worthless ambition, or a proof of the superiority of the memory
to the understanding.

Of the Forms, Positions, and Relations of Mineral Veins.

Mineral veins, like rock veins, intersect the strata at all
angles, and are also occasionally parallel to them, throughout
more or less of their courses. They imply a discontinuity of
the rocks through which they pass, and are, in fact, composed
of matter which has entered into the fissures that have been
formed by the causes which influence the positions of strata.
Hence, it is easy to understand how they are accompanied by
those dislocations of the including strata, the varieties of which
are numerous; although a fissure does not necessarily imply a
dislocation.

As veins may hold any direction with regard to the including
strata, so they may be placed in any position towards the
horizon. But from a mere comparison of chances, it is plain
that they must be far more frequently inclined than vertical ;
whence miners learn to distinguish between the upper and
under sides of a vein. It is observed, that when mineral veins
oceur in considerable numbers in any tract of country, they
maintain a sort of general parallelism; as if all the fissures to
which they owe their origin had been formed, at the same time,
by some common cause, or had been produced by the succes-
sive repetition of similar actions. ‘This, also, it is remarkable,
is sometimes the case where more than one set of veins exists,
and where the posteriority of the one is proved by their inva-
riably intersecting the other. This fact is remarkable in Corn-
wall, where the more ancient veins are directed, in a general

186 Dr. Mac Culloch.on Mineral Veins.

sense, from east to west, and the more recent from. north to
south.

Their longitudinal extent must evidently be limited, but it is
often considerable. They have been traced for two, and even
three, miles, in Cornwall; and it is said that one vein, in South
America, has been ascertained to extend for 80 miles.

It is easy to see, however, that in a case of this mature, the
union of some tendency to system, with a little inaccuracy, may
easily confound many veins together. Observations made in
such a spirit of extravagant generalization, must necessarily
excite distrust, when we adyert to the comparative length and
breadth of such a supposed continuous fissure, and to all the
circumstances under which these must have been formed.

The breadth of veins is extremely uncertain, varying from
less than an inch to many yards. The question of their depth
is more interesting, as it is believed by some to be indefinite:
it is at least said, that their depths have never been reached by
miners. If that were even true, it would not prove the truth of
an opinion so improbable, when we consider the circumstances
under which fissures must have been formed. When the sepa-
rated or dislocated strata preserve an accurate parallelism, the
same relative disposition must exist between the opposite sides
of the vein; and we may thus, if we please, imagine it intermi-
nable. But if the including strata have lost their parallelism
after separation, it is evident that, under one modification of
this, they may, or rather must, come into contact in some part
of the series, and that the vein will therefore disappear. . This
reasoning only takes a simple view of the consequences result-
ing from the appearances ; but if the hypothesis of some geolo-
gists should be admitted, which supposes that the materials of
veins were ejected from the depths of the earth, then indeed
they may be indefinite in their downward progress. But this is
pure speculation.

The absolute antiquity of veins, in any situation, is a subject
respecting which no conjectures can be formed; but there are
two modes of judging of their ages, within certain limits. It is
evident, in the first place, that they are all posterior to the in-

Dr. Mac Culloch on Mineral Veins. 187

duration of the strata, as they always imply fracture of these.
If, again, it shall’ be proved that any veins are found in the
primary strata, which do not also exist in the secondary, it
will follow that they are of a more early origin than the depo-
sition of the latter. It may be imagined, for example, that the
veins of Cornwall are of a prior date to the formation of the
English secondary rocks, because they do not occur in the
secondary districts. Yet there is no proof of this; unless it
could be shewn that secondary strata existed unbroken above
these veins, or until tin or copper veins shall be found in the
primary rocks, after removing the secondary, in the districts in
which these exist.

That there are veins of different ages, is, however, rendered
certain where two exist, and where, as often happens, the one
intersects the other. This cireumstance is not uncommon on
an extensive scale. In Cornwall, a large proportion, probably
all, of the easterly veins, are intersected by the northerly; and
it is remarked, that the former are metalliferous, and the latter
wanting in metals.

These intersections are attended by circumstances as inte-
resting to geology, as they are important in the art of mining;
in which they are often the source of much labour and expense,
and even of ruin. ‘As the first class of veins are frequently at-
tended by dislocations of the strata, the same accidents attend
the second; and, in the latest motions of the including rocks,
it evidently follows that the first order of veins is included:
Thus, in technical language, the effect of a second vein is to
produce a shift in the first, often attended by circumstances, in
the state and nature of its contents, which will be examined
hereafter.

The extent of such dislocations in veins is variable; as may
easily be understood from the remarks formerly made on the
motions of the disrupted strata, in which they, necessarily,
partake, Their direction is an object of the highest interest to
the miner; as it is only by being able to form some previous
judgment respecting it, that he is taught where to seek for the
interrupted continuation of that which he has Jost Experience,

188 Dr. Mac Culloch on Mineral Veins.

in different countries, often forms a tolerable, though not an-
infallible, guide for these; as must be very evident from con-
sidering the irregular displacements of strata; but such rules
are still less capable of being extended to other countries, or to
remote places. To determine whether the motion of one part
of an inclined yein is to be termed an elevation or a depression,
it is necessary to take the point of departure from the surface,
as in the case of dislocated strata. When a vertical vein is
shifted, it is evident that the adjacent rocks must all have been
moved by the same quantity in a horizontal direction; an eyent,
as formerly remarked, not favourable to the theory which sup-
poses the fractures of strata to be the effect of subsidence.

The last circumstance which relates to the forms of veins,
is their ramification, They are occasionally separated, and
again reunited; certain technical terms being, in mining coun-
tries, applied to the intermediate mass. In other cases, they
send out slender ramifications; and sometimes they are found
to ramify, at once, into many small branches.

I have thought fit to separate from that which is matter of
justifiable inference respecting the ages of veins, what can only
be considered as an hypothesis, and which is, further, neither
an intelligible nor an useful one. It has been said, that there
are epochas to be traced in metallic veins, or that the metals
are of different ages, Thus, for example, it is said that tin is
among the oldest metals, because it is found in granite, and
that lead is among the newest, because it occurs in the se-
condary limestone. I need not enumerate all the particulars
contained in assertions so unfounded; while a few simple facts
are sufficient to annihilate the whole system.

Cobalt occurs in granite, in many of the primary schists, and
in the secondary sandstones, Copper has been found through-
out the whole system, from granite up to trap inclusive, Lead
is found alike in the primary and secondary strata, and iron is
universal. I need not extend a list of exceptions that overs
whelm the rule. If, again, the nature, or imagined age, of the
rock which is traversed by a vein, is to bz made the criterion of
the age of the latter, or of the included minerals, it must be

Dr. Mac Culloch on Mineral Veins. 189

remembered, that a vein must traverse every rock that was in
existence at the time of its formation. The yein that intersects
the granite, intersects the superincumbent strata also; and tin,
copper, or lead, as it may happen, will occur in every part of it.
It may have required uncounted centuries to form all the strata,
but the yein is, comparatively, the work of a moment, It is a
Separate question, to what extent the adjacent including strata
modify the contents of their veins; and it is one that will be
examined hereafter.

Lastly, to attempt to classify metallic yeins according to the
nature of their contents, is to make arrangements worthy only
of the cabinet mineralogist; systems which philosophy dis-
claims. If there were an hundred, for example, instead of ten
or sixteen lead-glance formations, we must be content to re-
main ignorant of the ages of all that we cannot prove by the
incontrovertible marks already indicated.

There is not one circumstance, in the history of veins, whether
we regard their forms, positions, seats, origins, or the nature
and disposition of the minerals which they contain, which can
entitle us to conclude that they possess a resemblance or ana-
logy throughout the world; that they are of definite and de-
finable ages; or that they are, in any sense of the word, gene-
ral or uniyersal, Yet this doctrine is supported by geologists,
who imagine that the mines of New Spain are similar to those
of Hungary and Saxony. That Patrin, who had imagined the
earth organized and endowed with a vital principle, should pro-
tract a zone of copper, silver, and lead, from England through
Europe, Asia, and America, may be excused. But it is an
abuse of the term generalization, to extend it alike to the
visions of theorists and the inductions of philosophers.

Of the Seats and of the Contents of Mineral Veins.

The nature of the rocks in which mineral veins are found, is
in every respect an interesting object of inquiry; but it is neces-
sarily very limited, and, what is worse, cannot be converted to
any useful purposes, They may be said rather to belong to
countyies than to rocks; since, in one, that substance may be

190 Dr. Mac Culloch on Mineral Veins.

highly productive of veins and metals, which, in another, is
deficient and barren. That they are most abundant in the pri-
mary or ancient rocks, is, however, certain. They are also
more common in the stratified substances, namely, in gneiss,
micaceous schist, and argillaceous schist, than in granite, or in
the older porphyries. In the secondary or recent strata, they
occur chiefly in the lowest, as in that which has been called in
England the mountain limestone, and are scarcely found in the
upper strata, or above coal. In the same manner, they are
rare in the later trap rocks: -ut, if Hacquet’s observations are
correct, they occur at Nagyag, either in these, or, as he thinks,
in ancient volcanic rocks.

In the primary rocks, they are sometimes found at the june:
tions of granite with the strata, as happens in Cornwall and at
Strontian. But it is fruitless to attempt to derive any prac-
tical advantages from any thing yet known on this subject;
unless as the experience acquired in particular districts may be
a guide for these. The limitation of tin to Cornwall and a few
other spots, and its exclusion from countries formed of the
same materials,—the barrenness of gneiss in Scotland, com-
pared with its fertility in Saxony, may be added to a thousand
other instances, to prove that we must be content to possess
mines wherever they are found, without wasting our hopes and
our means in vain endeavours after them, where we have no
evidence of their existence. That much false philosophy should
have been adopted on the subject of mines, is a natural conse-
quence of that perversion of judgment which so often attends
the pursuit of wealth, and of that subversion of the reasoning
powers which is produced by examples of its sudden acqui-
sition.

The contents of mineral veins are various; and although the
metallic substances form the most valuable part of them, they
bear a very small proportion to the rest. No general rules re-
specting these contents can be given, as they vary in almost
every country, in every vein, and, often, in every part of a vein.
It is common, however, to find that the sides next to the in-
cluding rocks are formed of earthy matters of very ordinary

Dr. Mae Culloch on Mineral Veins. 191

aspect. In some cases, this substance is clay; in others, quartz
is found; and, not unfrequently, it consists of a conglomerate
formed out of fragments of the bounding rocks, united by va-
rious crystalline and earthy substances. It is common, in these
cases, to find that the including rock is more or less decom-
posed and altered, at its junction with the vein. It has also
been observed, that large detached fragments of the neighbour-
ing rock are sometimes included within the body of the vein.
In some cases, this occurrence presents an interesting varia~
tion ; as, when a vein traversing schist and granite together, is
found to contain fragments of the former within the space
bounded by the latter, and the reverse. This fact serves to
prove the extent of the revolutions, of a mechanical nature,
which must have taken place in the vein; either at the time, or
after the period, of its formation.

It is unnecessary to enumerate all the earthy minerals which
have been found in veins; but the most common are quartz
calcareous spar, barytes, and fluor. These, like the metallic
substances, are found in different parts of the vein, and are
crystallized in different forms, wherever cavities are present.
The metallic minerals are found variously disposed ; sometimes
lining similar cavities in their crystalline forms; at others, col-
lected into lumps, or deposits, in different parts of the vein ;
and at others, again, more generally diffused among the gene-
ral mass of materials. In some instances, only one metal is
found in a vein, in others, two or more; and these are some-
times distinctly separated, at others intimately mixed, so as to
be a source of much trouble to the miner. It is occasionally
found that the minerals, whether metallic or earthy, are ar-
ranged in layers parallel to the sides of the vein; and, in some
of these instances, there is, further, a perfect correspondence
on the opposite sides. Such, also, is the capricious disposition
of the metals, that they sometimes disappear altogether, after
having abounded through a large space; so that it becomes
necessary to abandon a mine that had once proved very pro~
fitable. It is owing to these perpetual variations in the con-
tents of mineral veins, that the characters of particular mines

Vou. XV. O

192 Dr. Mac Culloch on Mineral Veins.

‘are subject to such important alterations, and that chance, in
the ordinary acceptation of the term, baffles all the calculations
of the proprietor. Yet rules are still to be found in every min-
ing country. These, too, are, unquestionably, of occasional
value in practice; but they are always local, and if they may
sometimes serve valuable purposes in practice, they offer no
facts on which a philosophical geologist can possibly reason.

The intersections of veins are sometimes observed to praduce
variations in the nature and disposition of their metallic con-
tents ; but these, like most other rules, are of a local nature.
It is also said that masses of ore are found at the intersections
of more recent veins, and that intersecting veins of different
periods, necessarily differ in the nature of the metals, which
they afford. It is asserted, further, that in Cornwall, ‘if two
metalliferous veins cross from opposite sides of the line per-
pendievlar to their intersection, they become less productive at
and after the junction; but that, if they cross from the same
side of it, the reverse effect takes place.” It is further there
rematked, that, ‘after the intersection of a more recent vein,
the metallic produce of the ancient vein disappears.” If any
remarks of this nature have a value, it is not very intelligible.
The same proposition is both true and false at the same time;
since it is evident, that where the miner may have chanced to
work in an opposite direction, the very reverse effect must take
place. Like too many other conclusions, of a similar nature,
their chief value consists in warning us not to rely on observa-
tions made at hazard, and guided by no principles.

There is one circumstance, however, respecting the variation
of the contents of metalliferous veins, which is of importance
towards a rational theory of them; if, deed, it should prove
to be really founded on facts sufficiently extensive.

_ It is said to be a general remark, that, in all countries where
veins traverse strata of different natures, their metallic contents
vary with some relation to these; and that, in the same. vein,
the vicinity of some strata renders the vein more productive.
than that of others. But the facts adduced to prove the truth
of this observation are neither yery numerous nor very definite;

Dr. Mac Culloch on Mineral Veins. 193

it femains to be seen, by a further extension of rational and
unbiassed investigations, whether they are not swallowed up by
a mass of exceptions. It is said, for example, that in a vein
near Callington in Cornwall, passing through schist and gra-
nite, the copper which it contains is found in the former, and
the tin in the latter, part. It is further said, that in Cornwall,
similar veins aré poor in the schist, and rich in the eranite.
It is also asserted, that veins are most productive at the junc-
tion of the schist and granite, not only in Cornwall, but in
Silesia and elsewhere. There is not one exainple of this nature,
to which there are not exceptions many times exceeding them,
- for which the reports of the same observers may be consulted.
It would be endless to quote instances; as it would be fruitless
here to record all the observations that have been made on
these subjects ; since the conclusion would be, to draw, as might
equally be done without them, no conclusions. Whether, on
the subject of the influence which strata have over the contents
of veins, any exception ought to be made in favour of Derby-
shire, where this is said to occur, it seems fruitless to ask ;
until miners shall fairly enter on the field of accurate observa-
tion, or geologists, discarding their prejudices, shall seriously
turn their attention to a branch of the science which is, most
particularly, its opprobrium.

Of the Theory of Mineral Veins.

On such a foundation, it has been attempted to build theories
of mineral yeins; and, as is usual in similar cases, the opposing
opinions have.been maintained with a vehemence proportioned
to the want of evidence on both sides. It is necessary to state
these two hypotheses, before inquiring into the circumstances
by which either of them may be countenanced or opposed ;
and it is scarcely necessary to say, that the only important
question at issue, concerns the manner in which the contents of
the veins were formed and introduced ;. as the fissures in which
these are contained have formerly come under teview.
~ It is said, on one hand, that all the materials of veins have
been deposited from. the same universal solution whence the

O 2

194 Dr. Mac Culloch on Mineral Veins.

rocks were, on the same hypothesis, formed. But there are
two modifications, at least of this aqueous theory. While the
rocks were in the act of being precipitated from the universal
solvent, the veins were undergoing the same process; and
hence they are esteemed to be of different ages, corresponding
to those of the strata or rocks in which they lie. How such
an operation could be effected is not explained ; and it is fruit-
less to inquire, where, in lieu of ideas, we have only unmeaning
words. Time may be. better employed than in labouring to ac-
count for what is impossible. In the other modification, the
fissures were formed in the rocks yet soft or yielding, by drying
and contraction; and the metallic or other minerals, remaining
in the solution after the precipitation of the rocky valet
were then precipitated in these fissures. :

On the other hand, it is maintained, that the same power of
subterranean expansion which produced the fracture and dislo-
cation of the strata, introduced the materials into the veins, and
that they have crystallized from a state of fusion, not of solu- -
tion in water. Neither of these theories will require a very long
examination; but the arguments that relate to both are, in
some cases, involved together.

With respect to the aqueous hypothesis, it involves the same
fundamental objection made to the precipitation of rocks from
solution in water: it is at variance with the laws of chemistry.
That objection would still be a fatal one, though the hypothesis
should be limited to the filling of veins alone, though it were
conceded that the rocks had been produced in some other man-
ner, and though the production of veins was admitted to be
posterior to the consolidation of the strata in which they lie.
Even if the power of this imaginary universal solvent were
granted, the difficulties are still insuperable; unless it could be
proved why the metallic or other minerals of veins were not de-
posited every where alike; why, like those which form rocks,
they were not deposited in strata; and why they were not only
directed exclusively to fissures, and to a few of these in distant
and select places, but limited even to partial spots in the same
vein.

Dr. Mac Culloch on Mineral Veins. 195

- These are the leading objections to the general hypothesis,
and they are unanswerable. The few real arguments from facts
which have been adduced in support of it, are of small value,
and will require very little discussion.

If it be conceded, as is the fact, that many of the substances
found in veins are the produce of watery solution, there are
many others which, as far as we yet know, cannot be produced
in this manner. Not to enumerate all these, it is sufficient to
notice in general, the greater number of the metallic minerals.
It has been argued, that the minerals of veins are deposited in
layers parallel to their sides, precisely as ought to have hap-
pened on this hypothesis. To this it is easily answered, that
the fact is not so, except occasionally; as they are frequently
congregated in irregular lumps, or dispersed among the other
materials, or wanting for considerable spaces, or found lining
the insides of cavities. Neither of these occurrences ought to
be found, according to the hypothesis ; and, more particularly,
there could be no cavities on such a system uf deposition from
above. In such a case, also, the layers of minerals ought rather
to be parallel to the horizon than to the walls of the vein. . The
argument derived from the presence of rounded materials in
veins is worthless, because the fact itself is extremely rare. It
is an exception instead of a rule, and may be admitted without
involving the whole hypothesis.

‘ With respect now to the other theory, which presumes that
the contents of mineral veins have been injected from below, as
those of granite and trap veins have been, the difficulties are
assuredly not less, if they are not even greater. The arguments
for it rest partly on this very analogy; partly on real or imagi-
nary chemical facts relating to the production of minerals by
fusion ; partly on some mechanical appearances; and partly on
the principle of dilemma. If it be really a case of dilemma, the
one horn appears as fatal as the other, and there can be no
theory of mineral veins. ’

_ The argument from the analogy of trap and granite veins is
exactly one of those superficial resemblances, consisting. in
words rather than things, which it is painful to find in the writ-

196 Dr: Mac Culloch on Mineral Veins.

ings of such philosophers as those by whom it has been offered.
It serves to shew how weak the best of us are, when we suffer.
our prejudices or our wishes to interfere with our powers of
reasoning. It may be conceded, that the fissures have been
produced by the same subterranean changes which have dis-
placed the strata; yet this admission does not involve a con-
cession to the rest of the hypothesis, It does not necessarily
follow; that the mineral contents of these veins have been in-
Jected from beneath in a state of fusion, although the power of.
heat may have been the cause of the fissures themselves. The
presence of fragments of the including rocks in the veins, which
has also been used as an argument for this theory, is a fact of
just the same value: it proves the forcible displacement and
fracture of the strata, but nothing more.

As to the chemical arguments derived from the insolubility
of many of the contents of mineral veins in water, and their
production from fusion, it is easy to shew that many of them
certainly are produced from solution; that many others may.
have been generated in this way without a breach of chemical
laws ; and that some of them could not have been consolidated
from fusion. I shall reserve these particulars for a general view
at the end of this paper, when the several minerals producible
in either mode will be enumerated.

In the mean time, it is impossible to conceive how, if the
contents of these yeins had been injected in a state of fusion,
the fragments so often found in them should have escaped this
process. I will not here say, as has also been objected, that
clay could not.have been found in mineral veins on this prins
ciple ; because it is easy to understand how the infiltration of
water should have decomposed portions of the veins, in the
same manner as rocks are converted into clay, though flesh
situated beneath the surface.

Whatever objections may be made against the aqueous hy-
pothesis, from the peculiar dispositions of the minerals in the
veins, are at least equally valid against the igneous one. It’ is
impossible to comprehend how these could have been produced
from a state of igneous fluidity, any more than from’a state of

Dr. Mac Culloch on Mineral Veins, 197.

solution, It has also been said by the supporters of this hypo-
thesis, that the absence of the solvent water from the veins is
a proof that their contents. were not deposited from water. It
assuredly does not prove that ; while, as it respects the igneous
theory, it is merely an argument from dilemma, that proves
nothing in its favour, if it be not truly a case of dilemma. In
having recourse to this species of reasoning, the first step is to
establish the necessity of the alternative.
_ Another imaginary chemical argument has been derived from
the mutual impressions of co-existent crystals in the veins. This
is a view founded on the nature of granite, and other rocks
crystallized from fusion ; but it is an analogy which has been
abused, no less in this case, than in that which relates to the
nodules of the amygdaloids. The mutual impression of quartz,
or of chalcedony, and calcareous spar, does occur in these,
from successive infiltration and crystallization; and, according
to the order in which these substances are deposited, either
may impress the other, as I have fully shewn in my work on
the Western Isles. It is perfectly consistent with this to ima+
gine, that any number of minerals admitted, at distinct inter-
vals, into cavities, should present the same appearances ; and
that, in modes much more complicated than could happen from
any simultaneous crystallization from an uniform fluid of fusion.
But, in truth, though the inconceivable chemical agencies re-
quired to separate all the minerals that are found in a com-
pound rock, have been made almost a subject of ridicule against
the supporters of aqueous theories of rocks, it would be diffi-
cult to imagine any process more difficult than that which
should crystallize all the variety of earthy and metallic minerals
that are sometimes found together in veins, from an uniform
fluid of fusion, Chemists who will bestow a moment’s con=
sideration on this subject, will see without difficulty what it is
unnecessary to detail here.

Some farther arguments, as much mechanical as chemical,
have also been adduced in favour of the igneous hypothesis.
It has been said, as an argument from dilemma, that, on the

198 Dr. Mac Culloch on Mineral Veins.

aqueous theory, no close veins or deposits of minerals, sure
rounded on all sides by rock, could exist. But it is obvious
that these are equally impossible, on the other view of a cause.
Where there is no access for a watery solution, there is none
for an igneous fluid. To make use here, as has been done,
of a theory of igneous secretion, such as been applied to the
nodules of trap, is to adopt a scheme which is perfectly gratui-
tous, and to reject one the existence of which is proved. If
mineral veins have, in any case, been filled by a secretion from
the including rocks, there can be no choice between a process
which is actually proved to exist in nature, and one which, not
only has not been observed, but which is supported by no che~
mical analogy.

It has also been said, that the solidity or fulness of mineral
veins could only have happened from igneous injection ; as the
abstraction of the water after deposition, must have left cavities
or vacuities of some kind. With no small want of reflection,
it has also been said that cavities could only have been formed
in them on the igneous hypothesis, from the disengagement of
elastic fluids. These, it is plain, are conflicting statements ;
as, without a charge of captiousness, may be fairly urged.
The fact, such as it is, is quite as explicable on the one hypo-
thesis as on the other, and is alike worthless to both. ‘The
want of marks of gradual and regular deposition, is a negative
argument, which, if it proves one hypothesis to be wrong, does
not render the other right; and, with respect to the existence
of fragments already mentioned, the state of these is assuredly
calculated to prove any thing but that they have been sup-
ported and involved by an ignited fluid.

Such are the objections to an hypothesis, which, however
it might be deemed a necessary part of the general theory to
which it belongs ; and, however we may respect the talents of
its author and supporter, cannot command a moment’s atfen-
tion, unless it shall hereafter be most materially modified by
new views and new discoveries. Thus modified, it must ndeed
disappear; but its downfal does not involve that of the theory

Dr. Mac Culloch on Mineral Veins. 199

which considers granite and trap of igneous origin, and which
maintains that the strata have been elevated by forces directed
from below.

The pleasures of doubting have no charms to induce me to
give this discussion so conspicuous a place as it here occupies.
But facts are required by the reader; and, it is the duty of the
author to see that they are not so managed by theorists as to
mislead him; to place them so in array that he may form
the conclusions which they seem to justify; even though these
should leave the subject as they found it. The strength of
assertion which has been brought into this question on opposite
sides, leaves no choice in this case ; and, if the discussion shall
be said to prove nothing, it must be recollected that, to prove
the existence of falsehood, is, in these cases, the first step
towards truth.

Of the Minerals which are respectively produced from Solution,
and from the Action of Fire.

It remains now, as was promised, to examine by our che~
mical and mineralogical experience, how far any of the sub-
stances found in mineral veins are the produce of crystalliza-
tion from watery solutions, and in what cases they are crys-
tallized from a state of igneous fluidity, or from sublimation.
It is not intended to enter at large into this subject, because
our information is still incomplete. A general view alone will
be sufficient for the present purpose. The facts themselves,
as they regard the two theories which have been examined, are
singularly conflicting; although as far as they offer arguments
for either, the balance is palpably in favour of an aqueous one.
It is evident that these are the facts on which any future
hypothesis must chiefly rest ; whatever further considerations
may be required for explaining the various circumstances of
other natures which attend mineral veins.

In inquiring first respecting the earthy minerals, and in trying
to determine the number of those which may be produced
from watery solution, we are compelled to have recourse almost
entirely to the chemistry of nature; as the limited solubility of

200 Dr. Mac Culloch on Mineral Veins.

the earths prevents us from deriving much information from our
own circumscribed and cramped experiments. For the sake
of brevity, I have thought it expedient to throw them into the
form of a list; and, to save repetitions of the proofs on which
their aqueous origin rests, these may be here given in a pre-
liminary form.

The formation of quartz, chalcedony, and calcareous spar,
may almost be witnessed ; and that of the latter in particular
is so rapid, that it can be seen in calcareous caverns nearly
as well as the crystallization of ordinary salts. This substance
is generated both by infiltration, and in solutions of carbonat
of lime. Chalcedony is produced in the former way, and
quartz in both. In the work to which I have already referred,
it was also shewn that those veins which consist of quartz or
carbonat of lime, are generated in this manner.

In the remarks on the amygdaloidal structure, to be found in
the same place, I have proved that the theory of infiltration
explains the imbedded nodules of the rocks of this character,
and that these have been produced in this manner. Thus
there is established a considerable list of minerals formed by
means of aqueous solution. That which takes place in this
case may equally happen in a mineral vein.

Although we have not yet proved that all the other earthy
saline minerals, as they are sometimes called, such as gypsum,
barytes, &c., are produced from watery solution, chemistry and
analogy both render it very probable; and these may there-
fore be added to the aqueous list with little hazard of error;
certainly with much less than they could be referred to an
igneous origin. Lastly, we may pretty safely also refer to the
same division, those which are found associated or imbedded
in quartz, as disthene is.

The list, constructed from these various kinds of wiles
will therefore contain the following minerals, and possibly
many more; and, it is liere divided under these several heads
of more or less unexceptionable proof. I do not add those
which are imbedded in primary limestone, because it is pos-
sible, or more than possible, that some of these have undergone

Dr. Mac Culloch on Mineral Veins, 201

the process of fusion ; in which case their imbedded minerals
must be referred, as those of granite are, to an igneous origin.

Satine MINERALS,

Carbonat of lime. Carbonat of barytes.
Fluat of lime, Sulphat of barytes,
Gypsum. Carbonat of strontian,
Brownspar. Sulphat of strontian.
Arragonite. Boracite.

Wavellite.

With respect to some of these, it will be perceived that
the proofs are complete, as they are found in the, following
division :

MINERALS OF THE AMYGDALOIDS.

Quartz; including amethyst. Mesotype.
Chalcedony, in all its varieties. Nadelstein.
Opal. Leucite.
Sulphat of barytes. Sulphat of strontian.
Fluor spar.
Olivin. Prehnite.
Epidote. Laumonite. 4
Mica. Ichthy ophthalmite.
Chlorite. . Harmotome.
Steatite. Analcime.
Lithomarge. Stilbite,
Chloropheeite. Chabasite.
Conilite. Arragonite.
Brown spar.
To which may be added, as found sometimes in aqueous

quartz,

Disthene. Tremolite.

Epidote. Tourmalin,

Actinolite.
And as found in calcareous spar,
Emerald.

Ihave here limited the list of aqueous minerals strictly to
those which are supported by the proofs. above-mentioned ;
but, if those also had been enumerated which are found asso-
ciated together in cavities of veins, where one or more of the
number consists of minerals decidedly aqucous, it might have
been considerably extended. The mineralogical reader who is
thus furnished with the principles on which this catalogue has

202 Dr. Mac Culloch on Mineral Veins.

been constructed, may easily pursue further what it is here
unnecessary to detail more minutely.

In examining now the metallic minerals, so as to determine
which of them may have been formed from aqueous solutions,
we may first have recourse, partly to direct experiments in our
laboratories, and partly to analogies drawn from these. The
ready means which chemistry affords for producing many of
these substances, render these artificial proofs, if they may be
so called, much more complete than in the case of the earthy
minerals.

The other kind of proof which may be considered natural is,
as in the former case, drawn from their association with those
earthy minerals which are already proved to be of aqueous
origin. That association is in some cases very accurate, because
the metallic is imbedded in the earthy mineral; and thus the
proof from nature is complete. It is twofold, however ; the
metallic mineral being either crystallized within an earthy
crystallized one, as rutile is in quartz, or else disposed in strata
of aqueous origin, such as shale and secondary limestone, that
have not undergone the action of fire.

The natural proofs are not quite incontrovertible, when the
metallic minerals are merely associated in the cavities of veins
with those earthy ones which are of aqueous origin. Yet they
are, perhaps, sufficiently strong ; particularly when it is seen
that many of these are, in reality, substances which, in other
cases, carry much more decided proofs with them, either from
other natural associations, or from chemical experiments and
analogies. As the present remarks are not offered as including
a series of positive facts on which a theory is to be erected, but
merely as hints towards one, or as indicating the road that
ought to be followed in attempting to explain the origin of
mineral veins, any inaccuracies or doubtful particulars can be
of no moment. ‘The observations will answer all that is
intended, if they turn the attention of mineralogists to a subject
which ought to have been examined by those who have pro-
posed or adopted theories of this nature; and who, in this
case, seem to haye proceeded by inverting the rules of phi-

Dr. Mae Culloch on Mineral Veins. 203

losophy. It will hereafter be seen that some minerals, both
earthy and metallic, have a double origin, or are formed both
from fusion and solution; so that perhaps in some of the
cases here enumerated, some of these, such for example as
those which are concluded to be aqueous from their association
with carbonat of lime, may possibly be exclusively of igneous
origin. .

In examining the chemical evidence, it will be convenient to
class the metallic minerals according to their leading relations
of this nature, as it is not proposed to investigate every com-
plicated species or variety which mineralogists have described.
The following classification will answer the present purpose :

Metals ; including the alloys.

Oxydes ; whether simple or complicated.

Salts ; comprising carbonats, sulphats, muriats, phosphats,
arseniats, molybdats, tungstats, chromats and silicats ; or
combinations of more than one of these.

Sulphurets ; simple or complicated.

Phosphurets.

We do not yet know how many metals can be separated
from their solutions ina metallic state ; but gold, silver, copper,
and lead, can be procured in this manner with great facility.
These may, therefore, be metals of an aqueous origin, Pos-
sibly this may happen to many others, from deoxydating pro-
cesses in nature which we either have not examined, or which
may be unattainable in our experiments.

All the metallic oxydes which involve a large number of
these minerals, can be procured in the same manner; at least
in a powdery state. If artificial chemistry has not yet con-
trived to obtain these in a crystallized form, it must be recol-
lected that we cannot, like Nature, command the elements of
time. Yet, perhaps, the case of oxydulous iron, which may be
procured from the muriat by dissipating the acid, may be
esteemed an instance in point; although the application of
heat is necessary for this purpose. The oxyde appears here to
crystallize at the moment of its separation from the acid,

204 Dr. Mac Culloch on Mineral Veins.

without the necessity of a dry or subliming heat, although it
is not easy to ascertain the exact nature of this process.

If chemistry has not yet formed every complicated salt that
is found in the list of metallic saline minerals, it has pro-
duced so many that we may, with little hazard of error, con-
sider the aqueous process as fully competent to the production
of the whole. ‘That nature can exhibit some of them in a
crystallized form, such as the phosphat of iron, for example,
when we can only obtain them in our laboratories in a powdery
one, must be referred to the cause just noticed; namely, the
rapidity of our operations and the slowness of her's. As to
the silicats, our acquaintance with the real nature of this
combination, or the exact mode in which silica acts the part
of an acid, is as yet so recent and imperfect, that no opinion
can at present be given respecting them.

The igneous theory of metallic veins was supposed to be
supported by an incontrovertible argument derived: from the
sulphuret of iron, which, it was asserted, could not possibly be
formed from aqueous solution; and the same rule was in con-
sequence extended to all the other sulphurets. We shall
shortly see that nature does produce it from aqueous solutions
abundantly. In the laboratory it can be procured, merely by
allowing the serum of blood to stand for some time ; and, it is
also obtained from the decomposition of sulphat of iron by
animal matters. There is little doubt that other metallic sul-
phurets may be formed in the same manner ; and, it is a subject
that requires to be further investigated by those who may
have leisure for this purpose. These combinations can also
be procured in the aqueous method, by means of sulphuretted
hydrogen; a very probable agent in nature. In these latter
cases the Sulphurets are only obtained in a powdery form ; but
in the former the iron pyrites is crystallized.

Respecting the phosphurets, our direct experience is next to
nothing; but it must be remarked at the same time, that this
is at least a rare if not a doubtful modification of the metallic
thinerals, But the methods of decomposing the sulphuric and

Dr. Mac Culloch on Mineral Veins. 205

the phosphoric acids are so like, and all the points of analogy
between sulphur and phosphorus are so strong, that it is safe to
infer that phosphurets might be procured in the moist way as
well as sulphurets.

In now examining the evidence which nature affords from
the intimate association that exists between certain metallic
minerals and those earthy ones which are ascertained to be of
aqueous origin, it may be remarked that the chief of these
latter are calcareous spar and quartz, -Barytes and fluor are
less conspicuous in this respect. The union with calcareous
spar is rather more frequent than that with quartz; but, as
these different earthy minerals frequently occur together, and
particularly quartz and calcareous spar, it is not necessary to
distinguish the metallic ones that seem to be in some cases
peculiarly associated cither with the one or with the other.
The following list, therefore, contains those which are found in
these associations, arranged according to their chemical natures,
and under the most general terms.

METALS AND ALLoYs.

Gold. Bismuth.
Silver. Tellurium.
Arsenical silver. Mercury and silver; (amalgam.)
Tron, Antimony.
Copper. Arsenical iron ; (pyrites).
Arsenical Cobalt ; (white cobalt). Arsenical nickel (kupfer nickel).
; OXYDEs.
Cepper ; black and red. Arsenical oxyde.
Iron; oxydulous. Hematite. Uranium; green and black.
Lead ; minium. Manganese ; red and black.
Titanium ; rutile, anatase. Cobalt ; red and black.
SaALtTs.

Silver; muriat. Tungsten ; wolfram.
Copper; muriat, arseniat, phos- Zinc, carbonats,

phat. Bismuth; carbonat.

Lead ; phosphat, carbonat, sul- Titanium ; silicat. (Sphenc).
* phat, molybdat.
Tron; muriat, arseniat, carbo-

nat, phosphat.

206 Dr. Mae Culloch on Mineral Veins..

SULPHURETS.
Silver. Zinc.
Copper ; yellow, grey. Arsenic. Arsenic and iron.
Lead, lead and antimony. Antimony ; red and grey.
Mercury ; brown, red. Bismuth.

Tron.

The minerals which seem to carry the evidence of an aqueous
origin in their forms are the following :

Earthy phosphat of iron, Stalactitical manganese oxyde,
Stalactitical hzematites. red and black.

Bog iron ore, Stalactitical calamine.
Malachite. Stalactitical pyrites, whether of

iron or copper.

The last list is that which contains the minerals found in
secondary strata of aqueous deposition, and which do not
appear. to have experienced the influence of fire.

Gold. Oxydulous iron.
Quicksilver. Iron pyrites.

Muriat of quicksilver. Hematites.

Sulphuret of quicksilver. Iron stones and ochres.
Blue carbonat of copper. Cobalt; black oxyde.
Green carbonat of copper. Manganese ; black oxyde.

All of these are found in the preceding enumeration ; so that
these situations only offer proofs in confirmation of the present
views. rc

I must now proceed to examine the minerals, whether
earthy or metallic, which are the produce of igneous fusion, or
of sublimation from a state of vapour. The evidence respecting
these is also derived from two sources; from chemical ex-
perience, and from their positions in rocks which are known
to be the produce of fire. These last may be limited to gra-=
nite, the traps, and the volcanic rocks, though there seems no
reason to doubt that gneiss, micaceous schist, and other primary
strata might be added to these; in which case the catalogue
might be still further increased.

The earthy minerals which may be modified by artificial fire,
or which undergo the action of heat without destruction, are
the carbonats of lime, barytes and strontian, and the phosphat
of lime. Silica is sublimed in a crystalline form.

Of the metallic minerals it appears that every metal-may be

Dr. Mac Culloch on Mineral Veins. 207

sublimed by artificial heat; and they all admit of being cry-
stallized by fusion. All the sulphurets admit of being fused ;
all appear capable of being sublimed ; and, probably the whole
can also be produced in this way by a direct combination of
their ingredients. All the oxydes are produced from the
metals by heat, and some of them admit of being volatilized.
Under these circumstances also, some of them crystallize ; as
was observed in red oxyde of copper, formed in the cavities of
metallic vessels in Pompeii. It is probable that some of the
metallic salts, the arseniats for example, can be produced in
this way; but I cannot quote any satisfactory experiments on
a subject which, in all its bearings, is well worthy the atten-
* tion of those chemists who are interested in geology, and
whose leisure is greater than my own.

In examining the evidence which nature affords on this
question, the following is a list of such earthy minerals as are
found in the situations above-mentioned. It is probable that
many are omitted, as no evidence but what seemed unexcep~
tionable has been taken; and, in examining the entire cata-
logue of minerals, it will easily be found that there are some of
which the origin still remains uncertain, and which are there-=
fore excluded both from the aqueous and the igneous lists.

Eartuy MINERALS.

Quartz (by fusion and by Garnet.
sublimation.)

Felspar. Cyanite.
Mica. Zircon,
Hornblende. Fluor spar.
Actinolite. Spodumene. ~
Chlorite. Corundum.
Steatite. Beryl.
Serpentine. Topaze.
Chrysoberyl. Tourmalin.
Epidote. Schorl.
Apatite. Tremolite.
Pinite. Emerald.
Idocrase. Gabbronite.
Anthophyllite. Wernerite.
Andalusite, Pyrophysalite.
Stilbite. Lapis lazuli,
Jade. Asbestus.

VoL. XY.

208 Dr. Mac Culloch on Mineral Veins.

Fettstein. ' Hypersthene,

Talc. Diallage.

Opal. 5 Augit. ,
Sahlite.

Chrysoprase. _ Peridot (by fusion, and by sub-
limation.)

Hauyne. Melilite.

Meonite. Tabular spar.

Sommite. Melanite.

_. Leucite, Idocrase, 7
_ Pseudosommite. Ice spar.
Pleonaste. Arragonite.

Together with some other voleanic minerals, which are yet ill
defined.

The metallic minerals, thus found, are the following :

Copper. Sphene.

Oxydulous iron. Iron pyrites.

Galena. Oxyde of Tin. :
Graphite. Sulphuret of molybdena.

Chromat of iron.

Such is the balance, as far as it yet appears possible, to
construct a tolerable list of this nature, between the aqueous
and the igneous minerals. It would be highly improper, in the
present state of things, to deduce from it any thing respecting
a theory of mineral yeins. For, though all ‘the’ minerals ‘of
these were aqueous, or all igneous, we are equally at a loss to
conjecture whence they came, and how they are so limited and
so disposed as they are in veins. It might indeed be consi-
dered an argument in favour of an igneous theory, that the
mines of Nagyag lie in volcanic rocks. But it is evident that
this fact proves no more in this case than in that of granite or
trap ; since, in all of these rocks alike, aqueous infiltration
takes place, as well into the veins as into the volcanic and
trap amygdaloids.

But it is here worthy of remark, that of the earthy minerals
actually found in mineral veins, there are more of an aqueous
than of an igneous origin; although there are many more
igneous than aqueous minerals in nature. With respect to the
metallic ones, the difference is still’ more in favour of the
aqueous minerals. That many of both kinds have a double

Dr. Mae Culloch on Mineral Veins. 209

origin, is only one out of the numerous difficulties that beset
this subject. These are, in fact, such, and so apparently insur-
mountable at present, that a prudent geologist can do no
better than suspend his judgment on the subject; provided he
does, not also suspend his investigations. Both the theories
are before him, and he ought to try the facts by both, not by
one only, to the exclusion of the other. In this pursuit, he
ought to take into his views the formation of minerals by sub-
limation, and their production from infiltration; two pro;
cesses which have been neglected by former theorists. Not,
however, that these will, on either side, form in themselves a
theory ; because even were there not many more unintelligible
circumstances in veins, we are still unable to explain whence,
on either hypothesis, the minerals have arrived at their present
places. J. Mac CuLuocn,

r
'

Arv. Ill. Description of the Great Bandana Gallery, in
the Turkey Red Factory of Messrs. Monteith and Co.,
at Glaszow. - |

Tue benefits of liberal-mindedness are nowhere more fully

displayed than in the modern advancement of our chemical

arts. A quarter of a century ago, manufacturing chemists were
wont to shroud their operations in mysterious secrecy, like the
craftsmen of the dark ages, on a supposition, usually un-
founded, of their being possessed of some wonder-working
recipes, whose promulgation would be fatal to their interests.

At that period, the monied_, proprietors. of chemical factories

were rarely practical chemists. They were, therefore, obliged,

to place entire dependance in certain operative adepts, whom they
engaged at aconsiderable salary, to conduct their processes.

These persons, haying been previously employed as subordinate

menials in some similar manufactory, had acquired a smattering

notion of the routine of working: but, being entirely destitute

of education, and having no general views concerning the

business which they undertook to manage, they were perper,
P 2

210 Description of Messrs. Monteith and Co.’s

tually falling into difficulties, and committing mistakes from
time to time of the most ruinous description. Slight variations
in the qualities and state of the materials employed, in the
mode of mixture, in the temperature, or duration of the process,
occasioned variations of result, which they could neither foresee,
regulate, nor counteract; and, though the profits might be con-
siderable on a successful operation, yet failures were so frequent
and so expensive as to render the business not a little precarious
and uncomfortable. Hence we can understand why chemical
manufactories have undergone such vicissitudes of fortune,—
some raising their proprietors to unexpected opulence, others
sinking them to unlooked-for ruin. ’

The owners of chemical establishments, becoming at length
impatient of the vassalage in which they had been long held by
blundering and obstinate hirelings, began to inquire into the
principles of their peculiar arts, and were thus led to cultivate
the society of men of science. They now, for the first tinie,
learned that economy and precision could be ensured to their
processes only, by applying the same scientific rules which
medical censorship, backed by the authority of law, had for a
considerable time introduced with the happiest effect into the
formerly mysterious and uncertain processes of pharmacy.
Under this conviction, they consulted the chemical philosopher
on their difficulties and disappointments. Suggestions, of
greater or less value, were thus given and acted on, which led
to new questions on the part of the manufacturer, and new
researches on that of the chemist: and thus an alliance began
between theory and practice, which has, in a very few years,
carried several of the chemical arts of this country to an
extraordinary pitch of perfection.

Instances have, undoubtedly, occurred of chemists of some
reputation having given delusive advice to the manufacturer;
as we see chemical authors publish, as processes of art, formule
very disadvantageous and even absurd. These misdirections
are almost always to be ascribed either to neglect of experi=
menting with due-care on an adequate scale, or to superficial’
acquaintance with the principles of the science. It is very pos-

Great Bandana Gallery, Glasgow. 211

sible for a person to compile a dazzling .series: of class experi-
ments with grandiloquent explications, without being: either
a philosophical or a practical chemist.

The league between science and. art, which has, in: this
country, been the slow growth of necessity, was long ago
effected in France, to a considerable extent, by authority of
the government. ‘The illustrious minister, Colbert, fraught
with the most enlightened views of state policy, founded’ a
school of science to superintend and assist the dyeing manu-
factories of the kingdom. From that school, conducted as it
has been by a succession of eminent philosophers, have ema-
nated invaluable researches on the most beautiful, but, at the
same time, most intricate, of all the chemical arts,—researches
to which France owes much of her eminence in this very
profitable branch of her national industry.

The manufactory of Messrs. Monteith and Co. has been long
celebrated in the commercial world for the excellence and
beauty of its cotton fabrics. The madder-reds rival in bril-
liancy and solidity any ever produced at Adrianople; and the
white figures, distributed over the cloth, surpass, in purity,
elegance, and precision of outline, the original Bandana de-
signs. .

The opulent and enlightened proprietors have been careful
to avail themselves of every resource which the latest improve-
ments in chemistry and mechanics could supply. In this
respect, their factory deserves to be studied as a school of
practical science. The permission now granted of describing
their discharging-gallery is a proof of their liberality, as well
as of the confidence justly entertained, that the capital and
skill, now engaged in their establishment, are better securities
for the preference which their goods possess in the European
market, than the utmost mystery in conducting their processes.
Hence they have rarely refused to. strangers, respectable for
their rank.or science, permission to visit their manufactory,—
a fayour which it is impossible to enjoy without being gratified
and instructed.

Their new arrangement of hydrostatic presses was completed

212 Description of Messrs. Monteith and Co.’s

in 1818, under the direction of Mr. George Ridger, senior,
manager of the works. It consists of sixteen of these engines
beautifully constructed, placed in one range in subdivisions of
four ; the spaces between each set serving as passages to admit
the workmen readily to the back of the press. Each subdivision
occupies twenty-five feet; whence the total length of the appa-
ratus is one hundred feet.

To each press is attached a pair of patterns in lead, (or plates
as they are called,) the manner of forming* which will be
described in the sequel. One of these plates is fixed to the
upper block of the press. This block is so contrived that it
turns on a kind of universal joint, which enables this plate to
apply more exactly to the under plate. The latter rests on the
moveable part of the press, commonly called the si//. When
this is forced up the two patterns close on each other very
nicely by means of guide-pins at the corners, fitted with the
utmost care.

The power which impels this great hydrostatic range is
placed in a separate apartment, called the machinery-room.
This machinery consists of two cylinders of a peculiar con-
struction, having cylindric pistons accurately fitted to them.
To each of these cylinders three little force-pumps, ibis by
a steam-engine, are connected.

The piston of the larger cylinder is eight inches in diameter,
and is loaded with a top-weight of five tons. This piston can
be made to rise about two feet through a leather stuffing or
collar. The other cylinder has a piston of only one inch in
diameter, which is also loaded with a top-weight of five tons.
It is capable, like the other, of being raised two feet through
its collar.

Supposing the pistons to be at their lowest point, four of the
six small force-pumps are put in action by the steam-engine,
two of them to raise the large piston, and two the little one.
In a short time, so much water is injected into the cylinders,
that the loaded pistons have arrived at their highest points.
They are now ready for working the hydrostatic discharge~
presses, the water pressure being conveyed from the one apart-

Great Bandana Gallery, Glasgow. 213

ment to the other under ground through strong copper tubes of
small calibre.

Two valves are attached to each press, one opening a com-
munication between the large prime-cylinder and the cylinder
of the press, the other between the small prime-cylinder and
the press. The function of the first is simply to lift the under-
block of the press into contact with the upper-block; that of
the second is to give the requisite compression to the cloth.
A third valve is attached to the press, for the purpose of dis-
charging the water from its cylinder, when the press is to be
relaxed, in order to remove or draw through the cloth.

From twelve to fourteen pieces of cloth, previously dyed
Turkey-red, are stretched over each other, as parallel as pos-
sible, by a particular machine. ‘These parallel layers, are then
rolled round a wooden cylinder, called by the workmen, a drum.
This cylinder is now placed in its proper situation at the back
of the press. A portion of the fourteen layers of cloth, equal to
the area of the plates, is next drawn through between them, by
hooks attached to the two corners of the webs. On opening the
valye connected with the eight inch prime-cylinder, the water
enters the cylinder of the press, and instantly lifts its lower
block, so as to apply the under plate with its cloth, close to the
upper one. This valve is then shut, and the other is opened.
The pressure of five tons in the one inch prime-cylinder, is now
brought to bear on the piston of the press, which is eight inches
in diameter. The effective force here will, therefore, be 5 tons
x 8* = 320 tons; the areas of cylinders being to each other,
as the squares of this respective diameters. The cloth is, there-
fore, condensed between the leaden pattern-plates, with a pres-
sure of 320 tons.

The next step, is to admit the blanching or discharging liquor,
(aqueous chlorine, obtained by adding sulphuric acid to solution
of chloride of lime,) to the cloth. This liquor is contained in a
large cistern, in an adjoining house, from which it is run at
pleasure into small lead cisterns attached to the presses; which
cisterns have graduated index tubes, for regulating the quantity

214 Description of Messrs. Monteith and Co.’s

of liquor according to the pattern of discharge. The. stop-
cocks on the pipes and cisterns containing this liquor, are all
made of glass.

From the measure-cistern, the liquor is allowed to flow into
the hollows in the upper lead-plate, whence it descends on the,
cloth, and percolates through it, extracting in its passage, the
Turkey red dye. The liquor is finally conveyed into the waste
pipe, from a groove in the under block. . As soon as the
chlorine liquor has passed through, water is admitted in a
similar manner, to wash away the chlorine; otherwise on relax-
ing the pressure, the outline of the figure discharged, would
become ragged. The passage of the discharge liquor, as. well
as of the water through the cloth,’ is occasionally aided by a
pneumatic apparatus, or blowing machine; consisting of a large
gasometer, from which air subjected to a moderate pressure,
may be allowed to issue, and act in the direction of the liquids,
in the folds of the cloth. By an occasional twist of the air stop-
cock, the workman also can ensure the equal distribution of the
discharging liquor, over the whole excavations in the upper
plate. When the demand for goods is pressing, the air appa~
ratus is much employed, as it enables the workman to double
his product.

The time requisite for completing the discharging process in
the first press, is sufficient to enable the other three workmen to
put the remaining fifteen presses in play. ‘The discharger pro-
ceeds now from press to press, admits the liquor, the air, and the
water ; and is followed at a proper interval by the assistants
who relax the press, move forwards another square of the cloth,
and then restore the pressure. Whenever the sixteenth press
has been liquored, c., it is time to open the first press. In this
routine, about ten minutes are employed; that is 224 handker-
chiefs (16 x 14) are discharged in ten minutes. ‘The whole cloth
is drawn successively forward, to be successively treated in the
above method.

When the cloth escapes from the press, it is passed between
two rollers in front; from which it falls into a trough of water

Great Bandana Gallery, Glasgow. 215

placed below. | It is finally carried off to the washing and bleach-
ing department, where the lustre of both the white and the red
is considerably brightened.

By the above arrangement of presses, 1600 pieces, consisting
of 12 yards each = 19,200 yards, are converted into Bandanas
in the space of ten hours, by the labour of four workmen.

_. The patterns, or plates, which are put into the presses to
determine the white figures on the cloth, are made of lead, in
the following way. A trellis frame of cast-iron, one inch thick,
with turned-up edges, forming a trough rather larger than the
intended lead pattern, is used as the solid groundwork. Into
this trough, a lead plate about one half inch thick, is firmly put
by screw nails passing up from below. To the edges of this
lead plate, the borders of the piece of sheet-lead are soldered,
which covers the whole outer surface of the iron frame. Thus a
strong trough is formed, one inch deep. The upright border gives
at once great strength to the plate, and serves to confine the
liquor. A thin sheet of lead, is now laid on the thick lead-plate,
in the manner of a veneer on toilette-tables, and is soldered to it,
round the edges. Both sheets must be made very smooth be-
forehand, by hammering them on a smooth stone table, and then
finishing with a plane: the surface of the thin sheet (now at-
tached), is to be covered with drawing paper pasted on, and
upon this, the pattern is drawn. It is now ready for the cutter,
The first thing which he does, is to fix down with brass pins, all
the parts of the pattern, which are to be left solid. He now
proceeds with the little tools generally used by block cutters,
which are fitted to the different curvatures of the pattern, and he
cuts perpendicularly quite through the thin sheet. The pieces
thus detached are easily lifted out; and thus, the channels are
formed, which design the white figures on the red cloth. At the
bottom of the channels, a sufficient number of small perforations
are made through the thicker sheet of lead, so that the discharg-
ing liquor may have free ingress and egress, ‘Thus, one plate
is finished ; from which, an impression is to be taken by means

216 Great Bandana Gallery, Glasgow.

of printers’ ink, on the paper pasted on another plate. The im-
pression is taken in the hydrostatic press. Each pair of plates
constitutes a set, which may be put into the presses, and re-
moved at pleasure.

' Plate VI. is an elevation of one press ; A, the top, or entabla-~
ture; BB, cheeks of ditto, or pillars ; C, upper block for fastening
upper pattern to; D, lower or moveable block ; E, the cylinder ;
F, the sole or base; G, the water trough for the discharged
cloth to fall into; H, cistern or liquor-metre; dd, glass tubes
for indicating the quantity of liquor in the cistern; ee, glass
stop-cocks for admitting the liquor into the cistern; ff, stop-
cocks for admitting water; gg, the pattern-plates ; nn, screws
for setting the patterns parallel to each other; mm, snuffs per-
forated with a half inch drill. The lower iron frame has corre-
sponding pins, which suit these perforations, so that the patterns
are guided into exact correspondence with each other; hh, rol-
lers which receive and pull through the discharged cloth, from
which it falls into the water-box; k, stop-cock for filling the
trough with water; iii, waste tubes for water and liquor.

Glasgow, May 30th, 1823.

Art. IV. Lamarcx’s Genera of Shells.
[Continued from Vol. XV. p. 52.]

CLASS XII.
MOLLUSCA*.
ANIMAL soft, not articulated, having a head, which forms
a fleshy eminence on the fore part of the body, more or less
prominent, often of a round shape and generally furnished with
eyes, and sometimes, with from two to four, or at most, six
tentacula; sometimes surmounted by arms on the summit,
disposed in the form of a crown. Mouth, whether short or

* Molluscus soft ; an old word, nearly obsolete, derived from the Greek
Parancs,

Lamarck’s Genera of Shells. 217

elongated, tubular, exsertile, and usually armed with hard
parts. Mantle various, either with the margins free, at’ the
sides of the body, or with the lobes united into a bag which
partly envelopes the animal.

Branchiz various, rarely symmetrical, circulation double,
one ‘particular, the other general. Heart unilocular, occa-
sionally with two divided, very remote auricles. No gan-
elionated medullary cord, but a few dispersed ganglia, and
different nerves.

* Body sometimes naked, either with no internal solid parts,
or enclosing a shell, or some hard substance ; sometimes fur-
nished with an external covering, or ensheathing univalve shell.
Shell never composed of two opposite valves united by a
hinge.

The distinguishing character of the mollusca, is that they
have no vertebre, are wholly without articulations in all their
parts, and have a more oF less prominent head at the anterior
portion of the body.

- ‘The body of these animals 1s fleshy, soft, and eminently con-
tractile, and endowed with the power of reproducing the parts
that may have been destroyed. It is covered with a soft skin,
moistened by ‘a viscous glutinous fluid, which continually
exudes from it; the skin forms the true covering of the animal,
and is wholly independent of the solid testaceous envelope.
The blood of the mollusca is white or bluish ; their muscles
are white and very irritable, attached beneath the skin to
the substance of the mantle. The body is elongated, some~
times oval, slightly depressed, sometimes straight, and some-
times spiral at the hinder part. They have no true lungs, but
respire by the branchie. Their mouth is generally furnished
with hard parts; in some it is short, and has two jaws; in
others, it consists of a retractile trunk, with small teeth at its
internal orifice, but no jaws. The mollusca, which are fur-
nished with the trunk, as the buccina, volute, §c., are car-
nivorous, using it to perforate the shells of other shell-fish, in
order to prey on the animal within. Those with strong horny

218 Lamarck’s Genera of Shells.

jaws, (the cephalopoda,) shaped like a parrot’s bill, also live
on animal food. The limaces, helices, bulimi, and all that
have cartilagincus jaws, furnished with very minute teeth,
almost invisible, but sensible to the touch, live on herbs or
fruits.
_. The foot consists of a fleshy, muscular, and glutinous disk ;
it serves the animal to crawl with, and is placed at the lower
surface of the body, either on the fore part, or extending
through its whole lengih. The crawling foot is peculiar to the
gasteropoda and the trachelipoda. The mollusca, which have
non-operculated. shells, have but one muscle of attachment,
situated near the middle of the back ; those with opercula have
two, one which connects the animal with the shell, the other
belonging to the operculum. The operculum is usually round,
solid, horny or calcareous, and serves to close the mouth
of the shells when the animal is in a state of repose ; when it
comes out of the shell, it carries the operculum with it, and on
retiring it re-adjusts this natural door to the entrance of its
dwelling *. Some mollusca are naked, that is, have no exter-
nal shell, and are quite soft in all their parts—others, though
naked without, are provided with one or more solid bodies
internally, which sometimes are simply cartilaginous or horny,
sometimes cretaceous and lamellar, constituting a true internal
shell, This shell is usually spiral, and its cavity simple or
undivided, as in the bulle, bull, sigareti, §c,, but in many
of the cephalopoda, it is multilocular, its cavity being divided
into several regular chambers, by transverse partitions.

Other mollusca have shells, which are wholly external.

The mollusca are in general aquatic animals. Most of

' * The helix pomatia has a very solid, calcareous operculum; with
which it firmly closes the mouth of its shell at the approach of winter.
The wonderful rapidity with which the animal secretes the matter to form
this external defence, is strikingly exhibited in the following experiment,
communicated by,Mr. Henry Stutchbury. This gentleman and his brother,
took a helix pomatia on a warm summer’s day, when it was quite desti-
tute of aay. operculum, (for it casts it off at that season,) and placed it ina
vessel, surrounded by a freezing mixture. In the short space of twelve
hours it formed a complete solid operculum, in every respect similar to the
natural one, except that it was not quite so thick.—Tr.

Lamarck’s Genera of Shells. 219

them inhabit the sea; others live in fresh water; and others,
again, in moist, shady places, on land. Some of the latter,
however, are capable of supporting the heat of a brilliant
sunshine.

This class is divided into the five following orders :

First Order.
Preropropa*.

No foot, or arm, for crawling or seizing its prey. Two oppo-
site and similar fins, (nageoires,) adapted for swimming. Body
free, floating.

Second Order.
GASTEROPODA f.

Body straight, never spiral, nor enveloped in a shell ca-
pable of containing the whole of it. Foot muscular, united
to the body nearly through its whole length, situated under the
belly, and formed for crawling.

Third Order.
TRACHELIPODA ft
Body in great measure spiral, separate from the foot, and
always covered by a spirivalve shell. Foot free, flat, attached
to the inferior base of the neck, and formed for crawling.

Fourth Order.
CrpHaLopoDa §,

Body, except the head, contained in a bag-shaped mantle.
Head projecting beyond the bag, crowned with inarticulated
arms, furnished with air-holes, and surrounding a mouth with
two horny mandibles.

Fifth Order.
HeTEROPODA||.

No coronet of arms on the head; no foot, for crawling, under

* From alee, a wing, and 2s, a foot.

+ From yacIng, the belly, and xs, a foot.

t From rgaynaec, the neck, and wes, a foot.
§ From xepaan, the head, and wes, a foot.

§ From izes, different, and was, a foot.

220 Lamarck’s Genera of Shells.

the belly or neck, One or more fins, not disposed in pairs, or
regular order.

First Order.
PTEROPODA.

Most of the Pteropoda are small animals, with no appen-
dices, or only very short ones on the head. Some have a thin
cartilaginous or horny shell, and some have branchial fins.

1st Family.
Hyatzana. (6 Genera.)

1. Hyaleea *.

Body covered with a shell; two opposite, rather large, re-
tractile fins inserted at each side of the mouth. Scarcely any
head. Mouth terminal, situated at the junction of the fins.
No eyes. Branchiz lateral. Shell horny, transparent, ovate-
globular, posteriorly tridentate, open at the summit and two
posterior sides. si

The shell of the Hyalea appears, according to Forskahl, to
consist of two valves cemented together. The valves are un-
equal; the largest, dorsal, rather flattened below, the other
ventral, tumid, subglobular, and shortened anteriorly. The
middle one of the three posterior teeth, or points, is perforated.
On each side of the shell, is a very open fissure, to admit the
water to the branchiz.

Type. Hyalea tridentata +. (Monoculus telemus? Lz.)

Shell yellowish, pellucid, thin, very delicately striated trans-
versely; terminal point longer than the lateral.

Mediterranean. 2 Species. Pl. VIL. Figy 106 t.

* From tados, glass. ._.. .$ Having three teeth.

t We have given a figure of another, and, we believe, hitherto unpub-
lished, genus, which seems to belong’to this family. It was collected by
the late Mr. Crauch, on the Congo expedition, and presented to the Bri-
tish Museum, (where if is preserved, with anotlier species, apparently of
the same genus,) by the Lords Commissioners of the Admiralty. We
propose to call it, at the suggestion of a kind and learned friend, Bulan-
tium recurvum *, As the animal inhabitant, however, is qnite unknown to
us, we place it in this family, merely from the strong analogy which the

@ From Baaayliov, a purse 5: recuruum, recurved—the apex: being bent. |

Lamarck’s Genera of Shells, 221

2. Clio,
This genus has no shell,

3. Cleodora,

Body oblong, gelatinous, contractile, bi-alate; the head on
the anterior part of the body, the posterior covered with a shell.
Head projecting, very distinct, rounded, with two eyes, and a
small subrostrated mouth. No tentacula. Two opposite mem-
branous, transparent, cordate ale *, inserted at the base of the
neck.

Shell straight, gelatino-cartilaginous, transparent, in the form
of a reversed pyramid, lanceolate, truncated and open at the
top.

These animals, like the rest of the Pteropoda, float at ran-
dom, in the sea. |
Type. Cleodora pyramidata+. (Clio pyramidata. Lina.)

Shell triangular,- pyramidal, short; mouth obliquely trun-
‘cated. American Ocean. 2 species. Pl. VII. Fig. 108.

4. Limacina f.

Body soft, oblong, anteriorly very similar, in regard to the
head and ale, to the clio; but spirally contorted, at the hinder
part, and enclosed in a shell.

Shell thin, brittle, papyraceous, spiral; turns of the spire
united in a discoidal order, like the planorbis.

The limacina is ill named, for it rather resembles a helix
than a limax; but the shell being flattened on the upper part,

substance of the sheil bears to that of the Hyalea, until an opportunity
may occur of obtaining more accurate information respecting this interest-
ing species, It may be described as follows,

Shell transparent, very thin and fragile, hyaline, ‘corneous, hastiform,
apex recurved; open at both ends; superior aperture dilated, sharp
edged ; inferior round, very minute ; sides acute ; superior disk undulated ;
inferior rounded ; numerous transverse grooves on both sides. P. VII.
Fig. 107. The figure given (Plate vii. No. 8.) in Mr. Parkinson's Intro-
duction to the Study of Fossil Organic Remains, as a Hyalea, very much
resembles the other species of this genus, alluded to above.

* Wings. Two membranes, situated as described in the text, which,
when extended, serve as sails, whilst the animal is floating on the surface
of the water.

t Pyramidal. t From lima, a snuil.

222 Lamarck’s Genera of Shells.

from the whorls being united in a discoidal form, makes it still
more like a planorbis. It differs from the Cleodora, merely by
being spiral.
One Species. Limacina helicialis*. (Clio helicina, Gmel.)
North Seas. Whales are said to prey on the Limacina.

5. Cymbulia +.

Body oblong, gelatinous, transparent, enclosed in a shell.
Head sessile $; two eyes; two retractile tentacula; mouth fur-
nished with a retractile trunk. Two opposite, rather large,
rounded oval, branchiferous ale, connected, at the posterior
base, by an intermediate, lobe-shaped appendix.

Shell gelatino-cartilaginous, very transparent, crystalline,
oblong, in shape like a shoe, truncated at the summit; aperture
lateral, anterior.

One Species. Cymbulia peronit§.

Mediterranean, near Nice. Length about two inches, PI.
VII. Fig. 109.
6. Pneumodermon ||.

This genus has no shell.

Second Order.
GastERopopa. (Contains 7 Families.)

Body of the animal straight, never spiral, nor enveloped by
a shell, capable of containing it wholly; a foot, or muscular
disk under the belly, united to the body nearly through its whole
length, and used in crawling.

Some of the individuals of this order are naked, others have
a dorsal, but not enveloping shell, and others have an internal
shell, more or less hid under the mantle,

The Gasteropoda are divided into seven families; viz:, Trito-
niana, Phyllidiana, Semi-Phyllidiana, Calyptraciana, Bulle-

* Resembling a helix.

+ From cymbula, a little boat.

¢ That is, without any distinct neck.

§ OF M. Péron.

| From weve, the Jungs, and dsgaa, the skin,

Lamarck’s Genera of Shells. 223

ana, Laplysiana, and Limaciana. None of the animals of the
first family have any shell; we proceed, therefore, to the

2d Family.
PuYLuiripiana, (4 genera.)

Branchie situated under the border of the mantle, and dis-
posed in a longitudinal series round the body. The individuals
of this family respire water only.

Some of the Phyllidiana have no shell, either external or
internal; others are wholly, or in part, covered by a shell,
sometimes composed of one single piece, sometimes of a range
of moveable and distinct pieces.

1. Phyllidia.
This genus has no shell.

2. Chitonellus *,

Body creeping, elongated, rather narrow, resembling a cater-
pillar ; a multivalve shell on the middle of the back, through
its whole length, like a riband; valves alternate, longitudi-
nal, almost connected by their extremities; sides of the back
naked. Branchie disposed like those of the Chitones; foot
divided longitudinally by a deep furrow.

The valves of the shell, whilst the animal is alive, are sepa=
rate; but, when dead and contracted, several of them appear
to be united. The Chitonellus is nearly allied to the Chiton;
but the looser disposition of the dorsal shell admits of greater
freedom of motion to the right or left, and suffers the animal
to bend its body to either side with facility, like a worm. The
longitudinal furrow in the foot, probably serves for crawling on
the stems of marine plants.

Type. Chitonellus levis +.

Shell with smooth small valves; margins very entire ; last
valve pointed posteriorly.

New Holland. 2 Species. Pl. VII. Fig. 110.

* Little Chiton, + Smooth
Vou. XV, Q

224 Lamarck’s Genera of Shells.

3. Chiton *. ievtan.

Body creeping, oval oblong, convex, rounded at the extremis
ties, bordered all round by a coriaceous skin, and partly
covered by a longitudinal series of testaceous, imbricated,
transverse, moveable pieces, connected with the borders of the
mantle.. Head anterior, sessile ; mouth situated at the lower
part, coyered by a membrane, and furnished with numerous
teeth, some simple, some with three points, and disposed in
several longitudinal rows. No tentacula nor eyes. Branchie
disposed in series round the whole body under the border of
the skin; anus below the posterior extremity.

The shell of the Chiton is generally composed of eight
valves, sometimes of seven, or only six ; the middle valves are
rather larger than those at the extremities. They live in the
sea at moderate depths, and near the shore ; attaching them-
selves, but not permanently, to rocks and stones.

Type. Chiton squamosust. (Idem, Linn.) |

Shell with eight valves, semistriated ; body coverad with
small scales.

Mediterranean, and American Seas. Six Species. PI. VII.
Fig. 111. niet

4. Patella. sa a

Body entirely covered by an univalve shell; two pointed
tentacula on the head, with eyes at their exterior base.
Branchiew disposed in series all round the body, under the
border of the mantle; anus and hi for generation at =

right anterior side. a

Shell univalve, not spiral,’ enveloping, clypeiform, or flats
tened conieal, concave and simple below; no fissure’ in ‘the
margin; summit entite, inclining to the anterior sidé.

The summit is often the thickest part of the shell, and the
muscular attachment is very perceptible, on the concave side,
in many of the species ; and shews that the head of the animal
is always placed on the side towards which the summit inclines.

t xilev, a coat of mail.

+ Scaly. Lamarck’s second Species, His type is C, gigas.
t A small deep dis \,

Lamiarck’s Genéra of Shells. 225

Thé Patella are widest at the posterior side, and the periphery
of the shell is usually oval. They seem to live habitually in
the same place, though they probably have the power of
changing their situation from time to time.

Linnzus or Gmelin classed the fissurella, emarginula, navi-~
cella, umbrella, pileopsis, calyptraa, and crepidula, all under
the genus Patella.

Most of the Patelle have ribs, radiating from the summit to
the margin. ;

Type. Patella granatina*. (Idem, Linn.)

Shell angular, with numerous ribs and strie; apex, both
within and without, purplish black. Antilles. 45 species.
Pl. VII. Fig. 112.

3d Family.
Semi-Pityiiipiana. (2 genera.)

Branchiz situated under the border of the mantle, and dis-
posed in a longitudinal series, on the right side only of the
body. The animals breathe water.

In the disposition of the branchiz, the mollusca of this family
have considerable resemblance to those of the preceding, ex-
cept that in the Phyllidiana they occupy the whole of the
canal, which encircles the body between the border of the
mantle and the foot, whilst in the Semi-Phyllidiana they are
found only in that half of the canal which lies on the right
side,—whence the name. In other respects, the two families
differ considerably ; but, since the branchie are not placed, as
in the succeeding families, in an insulated cavity, Lamarck has
thought it necessary to assign them a distinct rank, in the order
‘of the Gasteropoda.
| ‘1, Pleurobranchus +.

_ Body crawling, fleshy, oval-elliptic,. covered by a projecting
mantle; fuot large and projecting like the mantle, so that the
two form an intermediate canal, and the body appears as if en-

* Garnet-coloured.
4 From qasvéa the side , and Beayxia, branchia, the lungs with which fishes
breathe. db
Q 2

226 Lamarck’s Genera of Shells.

closed between two equal shields. Branchiz on the right side,
inserted in the canal, and disposed in series, on the two faces
of a longitudinal Jamina. Mouth anterior, proboscis-shaped,
situated underneath. Two cylindrical, hollow tentacula, with
an. external longitudinal fissure, attached to the lamina which
covers the mouth. Aperture of the organs of generation in front
of the branchial lamina; anus behind ; both on the right side.

Shell internal, dorsal, thin, flattened, often oblique-oval.

One species. Pleurobranchus Peronit.

No further description.

Indian Seas. Pl. VIN. Fig. 113.

2. Umbrella.

Body very thick, subovate, furnished with a dorsal shell; foot
very large, prominent, smooth and flat on the under part, notched
before, posteriorly attenuated. Head not distinct; mouth at
the bottom of a funnel-shaped cavity, situated in the anterior
sinus of the foot. Four tentacula; two superior, thick, short,
truncated, with a fissure on one side, internally, transversely sub-
lamellar; two others thin, cristate, pedunculated, inserted at
the sides of the mouth. Branchiz foliaceous, arranged in series
between the foot and the border of the mantle, through the
whole length of the right side, both anterior and lateral. Anus
behind the posterior extremity of the branchie.

Shell external, orbicular, rather irregular, almost flat, slightly
convex above, white ; apex small, near the middle ; margin sharp ;
internal face slightly concave, presenting a callous, colourless
disk, depressed in the centre, and surrounded by a smooth
border.

M. de Blainville, who has described the animal of the um-
brella under the name of gastroplax, says, that its ‘ shell has
been found adhering to the inferior face of the animal.” M.
Mathieu, however, who has seen the species alive, at the Isle of
France, asserts that the shell is dorsal.

Type. Umbrella Indicat. (Patella umbellata, Gmel.)

_* Our fiepre is copied from that in the Annales;du Muséum. V. Pl. XVIII.
Fig. 1 and 2.

+ Indian umbrella, commonly cajled the Chinese parasol,

Lamarck’s Genera of Shells. 227

Shell somewhat concave, on the under side thin, and slightly
transparent; disc divided by radiating strie.

Indian Ocean, and common at the Isle of France. 2 Species.
Pl. VII. Fig. 114.

4th Family.
Catyrrraciana. (7 Genera.)

Branchiz placed in a cavity on the back, near the neck, and
projecting either in the cavity itself, or beyond it. The animals
breathe only water. -

Shell always external, covering.

The animals of this family, in respect of form and position of
their shell, are nearly allied to the phyllidiana, especially the
patellee; but the situation of their branchie, in an insulated
cavity on the back near the neck, sufficiently distinguishes them
from the individuals of that family, and requires that they should
be placed in a separate group. None of the shells belonging
to the Calyptraciana are operculated, wherefore the navicella
is decidedly excluded from this family. The seventh genus,
ancylus, is placed in it for the present, till the organization of its
animal inhabitant shall be more fully known.

1. Parmophorus *.

Body crawling, very thick, oblong-oval, rather widest at the
posterior end, obtuse at the extremities; mantle, cleft in front,
falling vertically over the body, and covered by a scutiform shell.
Head distinct, situated under the cleft of the mantle, with two
conical, contractile tentacula, with two eyes at their external
base. Mouth below, hid in an obliquely truncated funnel.
Branchial cavity opening anteriorly, but behind the head by a
transverse fissure, and containing two lamellar, pectinate, pro-
jecting branchie. Orifice of the anus in the branchial cavity.

Shell oblong, subparallelopipedal, rather convex above,
retuse at the extremities, anteriorly emarginate, sinus slight,
apex small, inclining to the posterior side. Lower surface
slightly concave.

Type. Parmophorus australis t.

* From magn, a shield, and deew, to bear.
t Seuthern,

228 Lamarck’s Genera of Shells.

Shell solid, smooth; of the same length as the back of the
animal; margin rather thick.

New Holland. Pl. VII. Fig. 115. 4 Species.
2. Emarginula*.

Body creeping. Two conical tentacula, with eyes at their
external base; mantle very large, partly covering the eum with
its folds ; foot broad, and very thick.

Shell scutiform, conical; vertex inclined; cavity simple} H
posterior margin notched, or emarginate.

The shells of this genus are generally small; some of them
are considerably convex, in form of a cone, inclined towards
the anterior margin, which is always the narrowest, and oppo=
site to that which has the fissure. In others, the cone is very
much flattened, and scarcely perceptible.

Type. Emarginula fissurat. (Patella fissura, Linn.)

Shell oval, convex-conical, decussated with longitudinal ribs

;

and transverse striz, sae whitish ; vertex curved ; margin
crenate. ;

European seas. Pl, VII. Fig. 116. 2 recent species, and’
3 fossil.

3, Fissurellat.

Head of the animal truncated anteriorly. Two conical tenta~
cula, with eyes at their external base; mouth terminal, simples)
without jaws. Two pectinate branchie projecting from the
branchial cavity on each side of the neck; mantle very ample,
projecting beyond the shell; foot wide, very thick. (a9

Shell scutiform, or depressed conical; concave on the under
side ; vertex perforated; foramen oval, or oblong; no spire.

Some of the Fissurellz are of considerable size and thickness..
The hole on the summit is never round. :

Type. Fissurella nimbosa§. (Patella nimbosa, Linz.)

Shell ovate-oblong, convex, brownish white, with violet-:
brown rays; longitudinal striae numerous, crowded ; margin
crenate; foramen oblong.

* Derived, we suppose, from emarginatus, in allusion to the fissure in the
posterior mergin.

+ A fissure.

+ Dim. from fissura, a little fissure.

§ Cloudy. Lamarck’s second species; his type is F, picta.

Lamarck’s Genera of Shells. 229

South of Europe. Pl. VII. Fig. 117. 19 recent species, and
1 fossil.

4, Pileopsis*.

Shell univalve, oblique-conical, curved forwards; summit
bent, almost spiral; aperture rounded oval; anterior margin
shortest, acute, terminating in a slight sinus ; posterior margin
larger, round; an elongated, arched, transverse muscular im-
pression under the posterior border.

- Animal.—Two conical tentacula, with eyes at their external
base. Branchie disposed’ in a row under the anterior border
of the cavity, near the neck.

According to M. Defrance, it is probable that the animal of
this species never removes itself from the place where it has
once fixed. He observed, in some fossil species, a support
formed for the shell, during the life of the animal, by successive
depositions of testaceous, matter, constituting a separate piece,
attached to marine substances, and preserving, on its upper
part, a pretty deep impression of the margin of the shell,

Lamarck subdivides this genus into, 1, Shells without any
known support; and, 2, Shells with a supportt. The first
subdivision contains eight species, the second two. Only the
first four species of the first subdivision are recent shells, all
the rest are fossil.

Type. Pileopsis ungarica}. (Patella ungarica. Lenn.)

' * From widos,a bonnet, and ofic, appearance, denoting the bonnet shape
of the shell, :

+ In the first number of his Genera of recent and fossil shells, Mr. G. B,
Sowerby gave his reasons for considering the Hipponix of De France (Pi-
leopsis of the second subdivision; Lamarck) to be a true bivalve shell, the
“ support” being, in fact, the lower valye; and in the 15th number, just
published, he adds the following additional arguments in confirmation of
his opinion: *‘ Lamarck’s Calypiraciens are Gasteropodes ; the shell being a
testaceous deposition from the mantle, and the Gasteropodes, not being
furnished with such a mantle under their foot, could not possibly deposit
testaceous matter in such a position, as to form what he has termed a
support, but which should more properly be called another valve ; conse-
quently, his ‘ Cabochons ayant un support connw’ should be placed among
the Conchifera, or we must suppose the absurdity of a Gasteropoda depo-
siting shelly matter from the lower part of its foot, where it is not furnished
with the necessary organs.”—This appears to us to be perfectly conclusive.

+ Hungarian.
7

230 Lamarck’s Genera of Shells.

Shell. pointed, conical, striated; yertex curved, involute ;
aperture widest in the transverse direction, internally rose-
coloured. Tes.

Mediterranean, Pl. VII. Fig. 118. 10 Species.

5. Calyptreea.
Animal unknown.

Shell conoidal, vertex erect, imperforate, subacute; base
orbicular. Cavity furnished with an attached, convolute la-
mina, or spiral diaphragm.

Type. Calyptrea equestris*. (Patella equestris. Linn.)

Shell suborbicular, convex-conical, thin, pellucid, white, with
acute, undulated, subtuberculated, longitudinal striz, increasing
in size towards the margin; vertex subacute, curved. Indian
Ocean. PI. VII. Fig. 119.

6. Crepidulat.

Animal......shead forked anteriorly. Two conical tenta-
cula, with eyes at their external base. Mouth simple, without
jaws, and placed at the bifurcation of the head. Branchia
single, subpenicillate, projecting beyond the branchial cavity,
on the right side of the neck. Mantle never extending beyond
the shell. Foot very small. Anus lateral.

Shell oval or oblong, convex externally, internally concave ;
spire very much inclined towards the margin; aperture partly
closed by a horizontal lamina.

The shell of the crepidula not only covers the animal, but
partly ensheathes it, for the chamber, formed by the lamina,
always contains a portion of its body. It has no operculum.
Found on rocks near the sea-side.

Type. Crepidula fornicatat. (Patella fornicata. Linn.)

Shell oval, posteriorly obliquely curved ; posterior lip concave.

Barbadoes. Pl. VII. Fig. 120. 6 species.

7. Ancylus§.
Body creeping, wholly covered by the shell. Two com-

* Equestrian. Lamarck’s third species. His type is C, extinctorium.

+ Dim. from crepida, 2 little shoe. i sa PSST

+ Arched. : :

§ Is this a corruption of ancile or ancilium,a sacred.shield? We can find
no such word as ancylus. But this is not the only instance in which our
author’s Latin names are somewhat difficult to translate. °

-Lamarck’s Genera of Shells. 231

pressed, slightly truncated ientacula, with eyes at their internal

base. Foot short, elliptical, rather narrower than the body.
Shell thin, obliquely conical; summit pointed, inclined

backwards; aperture oval ; margin very simple.

_ Type. Ancylus lacustris*. (Patella lacustris. Linn.)
Shell semiovate, membranaceous; vertex subcentral; aper-

ture suboblong-ovate. France. Pl. VII. Fig. 121. 3 Species.

5th Family.
ButLtzana. (3 Genera.)
Branchiz situated in a cavity, near the posterior part of the
back, and covered by the mantle. No tentacula,
1, Acera.
This genus has no shell.
2. Bulleat.

Body elongated oval, slightly convex above, divided trans-

versely into an anterior and a posterior part. Lateral lobes

_of the foot, with rather a thick border, and reflected upwards.
Head scarcely distinct. No tentacula. Branchie dorsal,
situated under the posterior portion of the mantle. Shell con-
cealed in the mantle, above the branchie, and not adhering to
the animal by any muscular attachment.

Shell very thin, partially convolute, and spiral on one side;
no columella, nor projecting spire; aperture very large, di-
lated at the upper part.

One Species. Bullea apertat (Bulla aperta. Linn.)

The last whorl of the volute, is terminated by the right
margin of the aperture. European Seas. PI. VII. Fig. 122.

3. Bulla.

Body oblong-oval, slightly convex, divided at the upper part
into two transverse portions; mantle posteriorly plicate. Head
very indistinct. No apparent tentacula. Branchie dorsal,
posterior; covered by the mantle. Anus on the right side.
Posterior part of the body covered by an external shell, ad-
hering by a muscular attachment. Shell univalve; oval-glo-
bular, convolute; no columella, nor projecting spire, or only

* On the pools. + As nearly allicd to the bulla.’
"} Op pen. § A bubble.

232 Lamarck’s Genera of Shells.

very slightly elevated; aperture the whole length of the shell;
right margin acute.

The bulla differs from the a by the shell ieitia com-
pletely convolute, always visible externally, and only partially
covered by the hinder part of the animal, which adheres to it
by a muscular attachment. The animal eyen hides com-
pletely in the shell, In the bullea the shell is impere
fectly convolute, wholly concealed by the posterior part of the
mantle, but not affixed to it, and not at all visible externally.

The genus bulla of Linnzeus was very vague and incon-
veniently extensive, as is evident from his B. ovwm, achatina,
ficus, terebellum, &c., shells which belong to very different
genera and even families. Bruguiére reformed the genus, and
distinguished it clearly from the ovule, but he left the bullea in
it, which Lamarck has since separated. The bulle are gene-
rally yentricose shells. (

Type- Bulla lignaria*, (Idem. Linz.) ;

Shell oblong, loosely convolute, attenuated towards the
spire, transversely striated, pale yellow; spire truncated ;
umbilicated. European Seas. Pl. VII. Fig. 123. 11 Species,

6th Family. ili
‘Lartysiana. (2 Genera.) i

Branchiz placed in an appropriate cavity, near the posterior
part of the back, and covered by an opercular scutcheon,
Tentacula,

The Laplysiana resemble large limaces, but their body’ is
broader, and larger towards the posterior part, and the borders
of the mantle are more ample. The head projects considerably
forward, and has four tentacula, two near the mouth, and two
behind. The latter are the largest, nearly ear-shaped, or
sometimes semi-tubular. They are distinguished from the
bullzeana, by the opercular scutcheon which covers the branchial
cavity, which, as well as the tentacula, is wanting in that
family. This scutcheon contains a horny or eretaceous piece,
the element of a shell, which has never the singular convolue
tion of that of the bulla, or bullea. The laplysiana breathe

only water.
* Belonging to wood.

Lamarck’s Genera of Shells. 233

1, Laplysia*.

Body creeping, oblong, convex, bordered on each side by a
wide mantlé, which, when at rest, covers the back. Head
supported by a neck; four tentacula, two superior, auriformt,
two near the mouth. Eyes sessile, in front of the auriform
tentacula, Scutcheon dorsal, semi-circular, subcartilaginous,
fixed by oné side, and covering the branchial cavity. Anus
behind the branchiz.

The mouth of the laplysia is cleft longitudinally, almost like
that of a hare, and the cavity of the stomach is lined with little
solid semi-cartilaginous, pyramidal bodies, which defend the
internal surface of that organ. The laplysia swims with ease,
but crawls slowly.

Type. ‘Laplysia depilanst. (Idem. Linn.)

Body livid, ‘blackish brown; posteriorly obtuse. Shell,’ a
dorsal, subcartilaginous scutcheon. Mediterranean. PI. VII.
Fig. 124: , 3 Species.

2. Dolabella §.

Body crawling, oblong, contracted antericrly, posteriorly
dilated, and obliquely truncated by an inclined orbicular plane;
borders of the mantle folded closely on the back. Four semi-
tubular tentacula disposed in pairs. Operculum of the branchiz
containing 2, shell, covered by the mantle, aad situated near
the posterior part of the back. Anus dorsal near the branchiz,
in the middle of the orbicular facet.

Shell oblong, slightly arched, securiform ; contracted, thick,
callous, and nearly spiral on one side; wider, flatter, and
thinner on the other.

Type:, . Dolabella Rumpihii\.

Shell thick at the base, callous, subspira.; dilated at the
upper part, thin, wedge-shaped. Indian Ocean. PI, VII.
Fig. 125. 2 Species.

* Amhucia, a sponge which cannot be cleaned,
-+ Their form is similar to that of a hare’s ear.

pi causing the hair to fall off—an effect attributed to 1 fetid whitish mucus,
which exudes when the animal is touched. It exdtes nausea, and even
Wik aes when the animal is touched, It excites naysea, and even vomiting.

§ A little axe, or hatchet.
|| Of Rumphius.

234. Lamarck’s Genera of Shells.

7th Family.
Limacrawa. (5 Genera.)
_ Branchie resembling a vascular net-work, extended over the’
side of an appropriate cavity, the aperture of which the animal
contracts or dilates at pleasure. They breathe only free air.

This family is very remarkable, the individuals which com-
pose it being the only gasteropoda that breathe nothing but free
air, although their respiratory organ is truly branchial. Hence,
Lamarck proposes to call them pneumobranchial. They are
quite, or very nearly, naked. Their body is long, creeping on
an attached ventral disk, and bordered at the sides by an, often
very short, mantle. They live in the neighbourhood of water,
or in cool, damp places.

1, OncurpruM.

This genus has no shell.

2. PARMACELLA.

Body creeping, oblong, inflated near the middle, where the
scutellum is situated, terminated by a tail, compressed at the
sides, acute above. Scutcheon oval, fleshy, adhering to the
posterior part, anteriorly free, containing ashell, and notched in
the middle of iis right border. Orifice for respiration, and
anus under the fissure in the scutcheon. Four tentacula; the
two posterior the largest. Orifice for generation between the
two tentacula, on the right side.

The Parmacella is a land animal, nearly allied to the limax,
but distinguished from it by the anterior half of its scutcheon
not being attachel to the body. In each genus the scutcheon
envelopes a solid, cretaceous body, which, in the parmacella,
has the true form of a shell, whilst, in the limax, it is the mere
element of one.

- Type. Parmacella caliculata *.

* Cup-shaped.— Stel] small, like a very flat bowl of a spoon, with a very
short papilliform spire contracted at its base, the aperture of its spire very
small, but the outer ip yery much spread out, and rather irregular”’—
“‘ covered on the outside with a light-brown, thin, horny epidermis.” The
specific name and desaiption of the Parmacella, which we have given as.
our type, is taken fron Mr. G. B. Sowerby. (Genera of Recent and Fossil

Shells.) ‘The shell, fron which our figure is taken, was furnished us by the
kindness of Mr, Henry $tutchbury. Lamarck gives but one spevies, P, Oli-

Lamarck’s Genera of Shells. 235

3. Limax *.

Body oblong, naked, creeping, convex above, furnished an-
teriorly with a coriaceous, subrugose shield ; below, with a flat
longitudinal disk. Four retractile tentacula ; the two posterior
largest, with eyes at the summit. Branchial cavity under the
shield; at the anterior part of the body. Orifice for respira-
tion, and anus, at the right side of the shield ; that for genera-
tion in front, between the two tentacula on the right.

The limax is a land animal; its skin is more or less rugose
and sulcated externally. It has much analogy with the helix
and bulimus, from which it differs principally in having no true
shell, and by its shield, and other essential peculiarities. It
creeps slowly, using its tentacula to feel the bodies that lie in
its way, and which it projects and retracts, in the same man-
ner that one turns the finger of a glove inside out. ‘The ani-
mal is hermaphrodite and herbivorous, and frequents shady,
damp places.

Type. Limaz rufus +. (Idem. Linn.)

Body longitudinally sulcated, reddish above, white under-
neath. Infests gardens, &c. Pl. VII. Fig. 127. 4 Species.

4. TesTacELLa. ?

Body creeping, elongated, limaciform, furnished with a shell
-at the posterior extremity. Four tentacula, the two largest
“with eyes at the summit. Orifice for respiration, and anus at
the posterior extremity; that for generation under the largest
tentaculum, on the right side.

Shell very small, external, subauriform; apex slightly spi-
ral; aperture very large, oval, obliquely effuse; left margin
involute.

The testacella is chiefly distinguished from the limax by the
very small shell which covers the posterior extremity of the
animal. It is, however, less allied to the limax than is the
“parmacella, with respect to the branchial cavity, and the posi-

vieri, and no specific description of the shell. Mr. Sowerby has adopted
“the name calyculata, “‘ on account of a little testaceous ridge, which sur-
rounds the aperture of the spire, formin a little cup.” Pl. VIL. Fig. 126.

* Aslug. + Reddish.

236 Lamarek’s Genora of, Shells.

tion of the anus. The testacella is seldom met with alive,
living almost constantly buried in the eround, where it preys on
earth-worms. i 1
One Species. Testacella haliotidea *+
No farther description. South of Fraice. Pl. VIL. Fig, 128.

5. Virrina ten
Body creeping, elongate, litnaciform jereatest part straight;
hinder part separate from the foot, spiral, and enveloped in a
shell. Several posterior appendages ofthe mantle spread over
the shell, apparently for the purpose oft: ‘cleaning it, and patsy
cover it. Four tentacula, the two antétior very short. Orifice
for respiration, and anus, véry far bacls: on the right side.
Shell small, very thin, depressed, fermitated above by a
short spire; last whorl very late. Aperture large, rounded-
oval; left margin arched, slightly invol ite,
The Vitrina is small, and frequents cool, shady places.
One Species. Vitrina pellucida }. 4
No further description. France. Pl. VII. Fig. 129.
v
Third Order. ©
‘TRacHELIPOD 4.”

Body spiral at the posterior part, which is separated from
the foot, and always enveloped in the;,shell. Foot free, flat-
tened, attached to the inferior base of the neck, or the anterior
part of the body, and serves for creeping. Shell spirivalve, en-
sheathing.

The trachelipoda differ from the gasteropoda, by the poste-
rior portion of the body being spirally:convolute, and by the
greater part of the foot being free, and only attached to the
inferior base of the neck, or fore-part of the body. The spiral
portion of the body never projects beygnd the shell, its natural
conformation not allowing it to extend,itself in a straight line;

All the trachelipoda are conchiferous ; their shell, generally
external, is always more or less spiral. ‘

The genera and species of this order are mich more nume-

* Like a hakiotis, . ‘a From vitrum, gies. t Transparent.

Lamarck’s Genera of Shells. 237

rous and diversified than those of the gasteropoda. The greater
part of them inhabit the sea, some live in fresh water, and
others on land. The shell of the latter is not at all, or only very
slightly, pearly, and generally has no other external projections
than the strie of growth,

Lamarck divides the trachelipoda into two sections.

Secrion I.
TracneEiropa, without any Siphon. (Phytiphaga *.)
No projecting siphon; animal generally breathes) by a hole.
The greater part feed on vegetables, and are furnished with
jaws.
Aperture of the shell entire ; base without any Wee dor-
sal notch, or canal.
This section contains ten families.
lst Family.
Cotimacgea. (11 Genera.)
Breathe air; some furnished with an operculum, others not ;
“tentacula cylindrical.
’ Shell spirivalve; no external projecting parts, except the
strie of growth; tight margin of the aperture often curved
outwards.
All the colimacea are land animals; the first nine genera
have four tentacula, the two last, only two.

. I. Hextx fF.

Shell orbicular, convex, or conoidal, sometimes globular;
spire but little elevated. Aperture entire, transverse, very ob-
lique, contiguous to the axis of the shell ; margins disunited by
the projection of the penultimate whorl.

' The Helix is distinguished from the pupa, by the general
form of the shell, which is never cylindrical, and by the borders
of the aperture being disunited; from the bulimus, by the
aperture being rather transverse than longitudinal, and its plane
very oblique, and almost perpendicular to the axis of the spire;
and from the planorbis, by the left margin of the aperture

* Herbitorous. + A spiral line,

238 _ Lamarck’s Genera of Shells.

being contiguous to the axis of the shell, whereas, in that ge-
nus, it is very remote from it. Lastly, the right margin, in ‘the
adult helix, is reflected outwards, which it never is in aquatic
shells. ‘The Helix is readily known by the projection of the
penultimate whorl into the aperture, whence Linnzus described
it, “ aperturd intus lunatd ; segmento circuli dempto.”

The animal has great resemblance to the limax.

The species of this genus are almost innumerable—Lamarck
describes only those in his own collection.

Type. Helix gigantea*. (Helix cornu militaire. Linn.)

Shell orbicular-convex, imperforate, solid, white; epidermis
red-brown; whorls transversely striated, aperture wide; lip
white within; margin reflected. Germany. PI. VII. Fig. 130.
107 species.

2. CAROCOLLA.

Shell orbicular, more or less convex, or conoidal, on the
upper part, with a sharp, angular periphery. Aperture trans-
verse, contiguous to the axis of the shell; right lip subangular,
often toothed on the lower part.

” The sharp edge of the last whorl, their being always orbicu-
lar, and sometimes considerably depressed, are the principal
characteristics of the shells of this genus.

Type. - Carocolla acutissima t.

Shell discoidal, convex on both sides, imperforate ; periphery
compressed and very acute; tawny; striz small, oblique, very
minutely granular; margin reflected, bidentate at the lower
part. Jamaica. PI. VII. Fig. 131.—18 Species.

3. Anostoma f.

Shell orbicular, spire convex and obtuse. Aperture rounded,
toothed within, ringent, turned upwards; margin of the ‘right
lip reflected.

“The singular position of the aperture, directed upwards, to~
wards the spire of the shell, is the characteristic of this genus,
and peculiar to it.

* Gigantic. Lamarck’s second species—his type is H. vesicalis.
+ Very acute. ¢ From ave, upwards, and oo, a mouth. |

Lamarck’s Genera of Shells. 239

Type. Anostoma depressum*, (Helix ringens. Linn.)

Shell suborbicular, convex on both sides, somewhat de-
pressed, obtusely carinate, imperforate, smooth, whitish ; a cir-
cular red line on the upper part; aperture with five teeth; lip
very much reflected. India. PI. VII. Fig. 132.—2 Species.

4, HELIcINA.

Shell subglobular, no umbilicus. Aperture entire, semi-oval.
Columella callous, transverse, rather flattened, with a sharp
edge forming an angle at the lower base of the right lip. Oper-
culum horny.

The Helicinz resemble small nerite, but the latter are sea
shells. They are distinguished from the helices by their trans-
verse columella, which is callous, depressed, and thin at the
lower part. They are land shells, and inhabit warm climates.

Type. Helicina neritella.

Shell ventricose, globular-conoidal ; smooth, white ; margin
reflected. Antilles. Pl. VII. Fig. 133.—4 Species.

5. Pupat.

Shell cylindrical, generally thick. Aperture irregular, semi-
oval, rounded, and subangular at the lower part; margins
nearly equal, reflected outwards, and disunited above by an
interposed columellar lamina.

Type. Pupa mumia t.

Shell cylindrical, attenuated, obtuse, thick, white ; furrows of
the whorls longitudinal, oblique; aperture red-brown, biplicate ;
margin reflected. Antilles. PI. VII. Fig. 134.27 Species.

6. CLAuSILIA §.

Shell generally fusiform, slender, summit rather obtuse.
Aperture irregular, rounded-oval ; margins united throughout,
free, reflected outwards.

The essential character of the clausilia, is that the two bors
ders of the aperture are completely united, free in their con-
tour, and reflected outwards.

* Depressed. + A puppet. $A mummy.

_.§ From claudo, to shut, because the aperture of the shell is closed bya
little apparatus, consisting of two small valves, situated in the penultimate
whorl, and not visible externally.

Vou. XV. R

240 Lamarck’s Genera of Shells.

Type. Clausila torticollis *.

Shell reverse, cylindrical, truncated ; stricz straight, ferrugi-
nous-red ; neck narrow, angular, and arched ; aperture without
teeth. Isle of Candy. Pl. VII. Fig. 135,—12 Species.

7. Buximus ¢.

Shell oval, oblong, or turrited; aperture entire, longitudinal;
margins very unequal, disunited at the upper part. Columella
straight, smooth ; no truncation or notch at the base.

The last whorl of the spire of the bulimus is larger than the
penultimate ; the shell is never orbicular, like the helix; and
it differs from the pupa, by the great inequality of the two
margins of the aperture, the right of which is sometimes con-
siderably thickened.

Type. Bulimus hemastomus t. (Helix oblonga. Gmel.)

Shell ovate-oblong, ventricose, subperforate, longitudinally
striated, whitish-yellow ; lip and columella purple. Guyana.
Pl. VII. Fig. 136.—34 Species.

8. ACHATINA.

Shell oval or oblong; aperture entire, longitudinal; right
margin sharp, never reflected. Columella smooth, truncated at
the base.

This genus is well distinguished from the preceding, by the
right margin never being reflected, and by wanting that on the
left; the columella being always naked, very smooth, and trun-
cated at the base.

Lamarck subdivides the genus into, 1. Those shells which
have the last whorl ventricose, and not depressed,—12 Spe-
cies ; and, 2. Those with it depressed, and attenuated towards
the base,—7 Species.

Type. Achatina perdix§. (Bulla achatina. Linn.)

Shell very large, ovate-oblong, ventricose, decussated, white,
apex rosy; light red, wavy, longitudinal streaks; columella
violet-purple ; interior of the lip white. Aviles. Pl. VII. Fig.
137.—In all, 19 Species.

* Wry-necked.
+ Bericos, insatiable hunger. What title this genus has to so strange a
name, we know not.

¢ Bloody-mouth. Wamarck’s secon | species. His type is B. ovatus.
§ A partridge.

Lamarck’s Genera of Shells. 241

9. SuccrnEa *.

Shell oval, or ovate-conical. Aperture large, entire, longitu-
dinal; right margin sharp, not reflected; united at the lower
part to a smooth, attenuated, acute columella. No operculum.

The Succinez live habitually on land, in the neighbourhood
of water, which they occasionally frequent. They are distin-
guished from the bulimi, by the right margin never being re~
flected, and from the lymnee, by their columella being free
from folds.

Type. Succinea amphibiut. (Helix putris. Lenn.)

Shell ovate-oblong, very thin, transparent, yellowish; spire
short ; aperture dilated, at the lower part, subvertical. France,
Pl. VII. Fig. 138,—3 Species.

10. Auricula ¢.

Shell suboval, or oval oblong. Aperture longitudinal, very
entire at the base, contracted at the upper. part, where the mar-
gins are disunited. One or more folds on the columella. Lip
sometimes reflected outwards, sometimes simple and sharp,

Land-shells, and distinguished from bulimus, by the folds on
the columella. The genus is subdivided into (1,) those with
the right margin reflected outwards—10 species; and (2) those
with the margin simple and sharp—4 species.

Type. Auricula Mide§. (Voluta auris Mide. Linz.)

Shell ovate-oblong, very thick, decussately striated, granular
above, white; chestnut brown epidermis ; spire short, conoidal ;
middle of the aperture contracted ; columella biplicate.

East Indies. PI. VII. Fig, 139.—14 Species.

11. Cyclostoma |,

Shell of variable form; sometimes subdiscoidal, sometimes
conical, or turrited, or subcylindrical. Whorls of the spire
cylindrical. Aperture round, regular ; margins circularly united»
open, or reflected by age. Operculum horny.

Land-shells, never pearly, generally thin, and without squame
or tubercles on the outside, distinguished from the paludinge
* Amber-coloured. + Amphibious. t A little cay.

Midas’s. || xuxAog, a circle, and clo.a, a mouth,

R 2

242 Lamarck’s Genera of Shells.

by the outward reflection of the margin of the adult shell, whilst

in that genus it is always sharp, and not reflected; from the

pupa, by the regularity of the aperture, which is never angular.
- Type. Cyclostoma volvulus *.

Shell trochiform, deeply umbilicate ; transversely striated ;
variegated with brownish white and red; spire acuminated ;
aperture white, or brownish ; margin reflected. Pl. VIL. Fig.
140. 28 Species, the two last doubtful.

2d Family.
Lymyzana. (3 Genera.)

Amphibious trachelipoda, generally provided with an oper-
culum, and two flattened tentacula without eyes at their sum-
mit. They live in fresh water, and come to the surface to
breathe air.

Shell spirivalve, generally smooth externally ; right margin
of the aperture always acute and not reflected.

1. Planorbis f.

Shell discoidal, spire flattened, scarcely projecting; all the
whorls visible on both sides. Aperture oblong, lunate, very
distant from the axis of the shell; margin not reflected. No
operculum.

Fresh water shells, generally thin, brittle, diaphanous ; the
whorls of some are subcylindrical, of others carinate or angular.
Aperture sublongitudinal, with an internal projection formed
by the penultimate whorl.

Type. Planorbis corneus tf. (Helix cornea. Lznn.)

Shell opaque, flat depressed above, broadly umblicate below ;
horn or chestnut brown; whorls transversely striated.

France. Pl. VII. Fig. 141. 12 Species.

2. Physa§.
Shell convolute, oval or oblong, spire projecting. Aperture

* A twisting. + From planus, flat, and orbis, an orb.

¢ Horny. Lamarck’s second species. His type, P. cornu arietis, Mr.
Sowerby considers as an Ampullaria.

§ Mr. Sowerby is of opinion, that there is not sufficient ground for forming
distinct genera, of this and the following shell. He has therefore struck out
physa, and placed it with the genus lymnza, (Genera of recent and fossil
shells, No. 8.)

Lamarck’s Genera of Shells. 243

longitudinal, contracted above. Columella twisted. Right
margin very thin, acute, partly projecting beyond the plane of
the aperture. No operculum.

The physz are fresh water shells, thin, brittle and generally
reverse. ‘Ihey are distinguished from the bulle by their pro-
jecting spire, and from the lymneza, which they otherwise much
resemble, by the aperture not being dilated, the right margin
projecting a little above its plane.

Type. Physa fontinalis*. (Bulla fontinalis. Linn.)

Shell reverse, oval, diaphanous, smooth, horn-brown, (luteo-
cornea ;) spire very short, sub-acute. PI, VII. Fig. 142.—
4 Species.

3. Lymnea.

Shell oblong, sometimes turrited, often rather ventricose be~
low, generally thin; spire projecting. Aperture entire longi-
tudinal. Right margin acute, its lower part, turning to the
left and ascending, passes over the columella towards the aper-
ture, forming a very oblique fold. No operculum.

The very oblique fold on the columella, distinguishes the
lymnza from the bulimus, and the regular uninterrupted plane
of the aperture, from the physa.

Type. Lymnea stagnalis+. (Helix stagnalis. Linn.)

Shell acute-ovate, ventricose, thin, transparent, longitudinally
substriated ; reddish grey ; last whorl subangular above; spire
conico-subulate ; aperture large ; lip broad.

France. Pl. VII. Fig. 143. 12 Species.

3rd Family.
Meraniana. (3 Genera.)

Operculated, fluviatile trachelipoda; breathe only water. Two
tentacula, Operculum horny.

Borders of the aperture of the shell disunited ; right margin
always acute,

Most of the shells of this family are exotic, and are covered
with a brownish green or blackish epidermis.

* Of the springs. Lamarck’s second species ; his type is P. castanea.

+ Of stagnant waters. The first species, L. columnaris, Lamarck has re-
moved to the genus Achatina—See erratum. Vol. vii. p. 678.

244 Lamarck’s Genera of Shells.

1. Melania *.

Shell turrited. Aperture entire, oval or oblong, effuse at the

‘base. Columella smooth, incurved. Operculum horny.
Type. Melania truncata t.

Shell turrited, apex truncated, solid, blackish brown; ribs
longitudinal, the superior most projecting, decussated by nu-
merous transverse strize ; whorls plano-convex..

Guiana. Pl. VII. Fig. 144. 16 Species.

2. Melanopsis f.

Shell turrited, aperture entire, oblong-oval. Columella cal-
lous above, truncated at the base, separated from the right lip
by a sinus. An operculum.

The callus on the upper part of the columella distinguishes
the Melanopsis from the Melania, as well as its being truncated
at its base like the achatina, which is never the case with the
Melania.

Type. Melanopsis levigata §.

Shell ovate-conical, smooth, chestnut colour; six whorls,
rather flattened, convex at the spire; the last whorl towards
the spire the longest.

_ Archipelago. Pl. VII. Fig. 145. 2 species.
3. Pirena|l.

Shell turrited; aperture longitudinal ; right lip acute, with
a sinus at its base, and another at the summit. Base of the
columella curved towards the right margin. Operculum horny.

Principally distinguished from Melanopsis by having no
callus on the columella, and from that genus and melania by
a sinus both at the base and summit of the right lip.

Type. Pirena terebralis%. (Strombus ater, Linn.)

Shell subulate-turrited, smooth, black; whorls flattened ;
aperture white.

India. PI. VII. Fig. 146. 4 species.

* From jenas, black. 1

+ Truncated—2nd Species. Lamarck’s type is M. asperata.

$ From penas, black, and ois, a face. ‘

§ Smooth—2nd Species. Lamarck’s type is M. costata. ;

|| From aeiga, the point of a sword 2 q rom terebro, to pierce.

Lamarck’s Genera of Shells. 245

4th Family.
PERIsTOMIANA. (3 genera.)

Operculated, fluviatile trachelipoda; breathe only water.
Shell operculated, conoidal, or subdiscoidal; borders of the
aperture united.

The shells of this family all belong to fresh water, and have
a thin greenish or brown epidermis. They are distinguished
from the three preceding genera by the margin of the aperture
being united.

1. Valvata*.

Shell discoidal or conoidal; whorls cylindrical; spiral
cavity complete, or not deranged by the penultimate whorl;
aperture rotundate; margins united, acute: operculum orbi-
cular.

Type. Valvata piscinalis+.

Shell globose-conoidal, subtrochiform, perforate, whitish ;
about five whorls; apex of the spire obtuse.

France. Pl. VII. Fig. 147. 4 species are known, but La-
marck only describes the above.

2. Paludinat.

Shell conoidal, whorls rounded or convex, modifying the ~
spiral cavity; aperture rounded oval, longitudinal, angular at
the summit; the two margins united, acute, never curved out-
wards; operculum orbicular, horny.

The paludine generally live in fresh water, though some
inhabit brackish, and even salt, water. They are distinguished
from the valvatz by the somewhat elongated and angular form
of the aperture.

Type. Paludina vivipara§. (Helix vivipara, Linn.)

Shell ventricose-conoidal, thin, diaphanous, very delicately
striated longitudinally, brownish green ; obsolete, brown-red,
transverse bands ; five whorls, rotundate, turgid ; sutures very
marked.

France. PI. VII. Fig. 148. 7 species,

* Valia, a folding door, or valve. t Of the pools.
} From palus, a marsh. § Viviporous

246 Lamarck’s Genera of Shells.

3. Ampullaria *.

Shell globular, ventricose, umbilicate at the base; no callus
on the left lip; aperture entire, longitudinal; margins united ;
right margin not reflected ; an operculum.

The last whorl is, at least, four times as large as the penulti-
mate. The columellar lip projects, and is reflected over the
umbilicus, forming a half funnel, but no callus. The shells of
this genus are generally large.

Type. Ampullaria Guyanensis +.

Shell ventricose-globular, solid, longitudinally, and unequally
striated; epidermis brown ; six whorls; last whorl the largest ;
aperture orange-coloured.

Rivers of Guiana. Pl. VII. Fig. 149. 11 species.

5th Family.
NERITACEA. (4 genera.)

Operculated trachelipoda ; some inhabit fresh water, others
are marine.

Shell fresh-water or marine, semi-globular or flattened oval ;
no columella; left margin of the aperture acute, transverse,
and resembling a half partition, with which the operculum

articulates.
1. Navicella f.

Shell elliptical or oblong, convex above; summit straight,
depressed to the margin; under side concave. Left margin
flattened, acute, narrow, toothless, transverse §; operculum
solid, flat, with an acute lateral tooth.

Exotic, fresh-water shells; distinguished from nerita and
neritina by the summit not being spirally convolute. The
transverse, left lip, never covers half the cavity.

Type. Navicella tessellata ||.

Shell oblong elliptical, thin, diaphanous, tessellated with
yellowish and brown oblong square spots; vertex maginal, not
projecting.

Rivers of India. Pl. VIII. Fig. 150. 3 species.

* Ampuila, a wide-bellied bottle. + Of Guiana. + Pro navicula, alittle boat.

s The transverse position of the flattened left lip gives the shell, when
held with the concave side upwards, the appearance of a little boat with
a half-deck. || Tessellated—3rd Species.. Lamarck’s type is N. elliptica.

Lamarck’s Genera of Shells. 247

2. Neritina *.

Shell thin, semi-globular or oval, flattened on the lower
part; no umbilicus. Aperture semi-circular; left lip flattened,
acute; no teeth, nor crenations on the internal face of the right
margin. Operculum furnished with a projecting apophysis, or
lateral tooth, on one side.

Fresh-water shells, generally thin, and smooth externally.

Type. Neritina pulligerat. (Nerita pulligera. Linn.)

Shell ovate, delicately striated, blackish. brown, dotted with
small round young shells, which adhere to it; lip dilated, thin,
white internally; margin acute; lower border yellowish; lip
crenate. :

India. PI. VIII. Fig. 151. 21 species.
5 3. Nerita f.

Shell solid, semi-globular, flattened on the lower part; no
umbilicus. Aperture entire, semi-circular; left lip flattened,
septiform, acute, often crenate; internal face of the right lip
crenate. Operculum furnished with an apophysis.

All sea-shells, solid, rather thick, and agreeably varied in
colour. The spire is but little elevated above the last whorl.
The operculum is crescent-shaped, horny, or calcareous, and
exactly closes the aperture. When the animal comes out of
the shell, the operculum falls back on the flat part of the colu-
mella, like a shutter. The nerita differs from neritina by the
internal face of the right margin being crenate, and from natica
by having no umbilicus.

Type. Nerita exuvia§. (Idem, Linn.)

Shell thick, white, spotted with black; ribs transverse, those
on the back acute, rough-squamose, decussated by longitudinal
strize ; interior of the lip crenate; upper part of the margin
verrucose, and toothed.

Indian Ocean. PI. VIII. Fig. 152. 17 species.

4. Natica.
Shell sub-globular, umbilicated; aperture entire, semi-

* Dim. of Nerita, + Bearing its young.

From yngilng, the Greek name for a kind of sea shell,—from vew, to swim,
because it swims on the sea. § Exuvia, spoils.

248 Lamarck’s Genera of Shells.

circular ; left lip oblique, not crenate, callous; form of the
umbilicus modified by the callus, and sometimes covered by it ;
right lip acute, always smooth internally ; operculum generally
solid, calcareous.

Sea-shells, distinct from nerita, by the umbilicus, and by the
columellar margin not being crenate, but smooth, and callous,
and by the smoothness of the interior of the right lip.

Type. Nerita glaucina*. (Idem, Linz.)

Shell suborbicular, inflated, thick, smooth, whitish yellow,
and ceerulescent ; spire short, oblique; callus subdivided, partly
covering the umbilicus, red.

Bay of Campeachy. PI. VIII. Fig. 153.—31 species.

6th Family.
Iantuineat. (1 Genus.)

Shell inflated, conoidal, thin, transparent. Aperture triangu-
lar. Columella straight, projecting beyond the base of the
right lip; a sinus in the middle of the latter. No operculum,

Sea shells, always found at the surface of the water, of a vio-
let colour throughout, very thin, transparent, and brittle.

Type. Janthina communis}. (Helix Ianthina. Lenn.)

Shell ventricose-conoidal, longitudinally sub-rugose, trans-
versely delicately striated, violet; last whorl large, angular ;
apex of the spire rather obtuse. Mediterranean. Pl. VIII. Fig.
154,.—2 Species.

7th Family.
Macrostomiana§. (4 Genera.)

Shell auriform, aperture extremely dilated, margins disunited.
No columella, nor operculum.

1, S1GARETUs.

Shell sub-auriform, nearly orbicular ; left margin short, spiral.
Aperture entire, very dilated, longitudinal; margins disunited.

The shell of the Sigaretus is concealed under the mantle of
the animal.

* Bluish, or sea-green colour. + From fanthum, a violet.
$ Common. § From paxpoc,large, and close, a mouth.

Lamarck’s Genera of Shells. 249

Type. Stgaretus haliotoideus *. (Helix haliotoidea. Linn.)

Shell auriform, back depressed, convex; undulately striated
transversely, whitish; spire very obtuse; aperture very dilate ;
umbilicus covered. Aélantic Ocean. PI. VIII. Fig. 155.—4
Species.

2. STOMATELLA ft.

Shell orbicular or oblong, auriform, imperforate. Aperture
entire, large, longitudinal ; right margin effuse, dilated, open.

Distinguished from stomatia, by not having the transverse
rib of that shell, nor the right lip so much elevated; and from
the haliotis, by wanting the foramina, or row of perforations,
which mark that genus. They are all sea shells, pearly ex-
ternally.

Type. Stomatella sulcifera }.

Shell sub-orbicular, convex, thin, transversely sulcated, very
delicately striated longitudinally, reddish-grey ; furrows rather
rough ; spire slightly projecting. New Holland. PI. VIII. Fig.
156.—5 Species.

3. StomatTia §.

Shell auriform, imperforate; spire prominent. Aperture en-
tire, large, longitudinal ; right and columella lip equally ele-
vated. Dorsal rib transverse, tuberculated.

Distinguished from haliotis by the dorsal rib being imperfo-
rate. Sea shells, sometimes very pearly.

Type. Stomatia phymotis ||. (Haliotis imperforata. Chemn.)

Shell resembling a haliotis, ovate-oblong, back convex, stri-
ated, nodular, silvery; spire minute, contorted ; lip thin, acute.
Indian Ocean. PI. VIII. Fig. 157.—2 Species.

4, Haxroris 7.

Shell auriform, usually flattened ; spire very short, sometimes
depressed, sublateral. Aperture very large, longitudinal, and,
in the perfect shell, entire. Disc perforated with holes, dis-

* Like a haliotis. + Dim. from cloa, a mouth.

+ Furrowed. 3d Species.—Lamarck’s type is |S. imbricata.

§ Krom the same Greek word as the last genus.

|| FP puja, a mushroom, or the knotty excrescence of ua trec, and ov, an ear.
"| From 4s, the sea, and 2s, an ear.

250 Lamarck’s Genera of Shells.

posed in a line parallel to, and near the left lip; the last hole
incomplete, forming only a notch. No operculum.

Type. Hahotis Iris*. (Idem. Grel.)

Shell rounded-oblong, very large, thin, rugose-plicate, pret-
tily varied with green, red, and blue; spire sub-prominent, ob-
tuse; left lip elevated. New Zealand. PI. VIII. Fig. 158.—
15 Species.

8th Family.
Puicacea +. (2 Genera.)

Aperture of the shell not dilated ; columella plaited.

All sea shells, distinct from the Auricule, which are land
shells, by their general form and projecting spire; and from
the Volute, Mitre, §c., by having no notch at the base of the
aperture.

1. ToRNATELLA f.

Shell convolute, ovate-cylindri¢al, generally striated trans-
versely ; no epidermis. Aperture oblong, entire ; right lip acute ;
one or more plaits, usually thick and obtuse, on the columella.
Spire prominent.

Type. Tornatella flammea§. (Voluta flammea. Linn.)

Shell oval, ventricose, transversely striated, white, with red,
wavy, longitudinal markings; spire conoidal, columella with
one fold. PJ. VIII. Fig. 159.—6 Species.

2. PyRAMIDELLA |.

Shell turrited, no epidermis. Aperture entire, semi-oval ;
outer lip acute. Columella straight, projecting at the base,
subperforate ; three transverse folds on the columella

Type. Pyrmidella dolabrata{. (Trochus dolabratus. Linn.)

Shell conico-turrited, perforate, smooth, white, with sur-
rounding yellowish lines ; columella recurved ; interior of the
lip toothed, and sulcated. South America. PI. VIII. Fig. 160.
5 Species.

* A rainbow, 2d species.—Lamarck’s type is H. mide. °

+ From plico, to fold. $ From torno, to turn in a lathe.
; Yellow, or flame colour. " || From pyramis, a pyramid.
- Y Cut with an axe, 2d Species—Lamarck’s type is P. terebellum.

Lamarck’s Genera of Shells. 251

9th Family.
Scatartana. (3 Genera.)

No plaits on the columella; margins of the aperture circu-
larly united. All sea shells. ‘

The shells of the Scalariana have a tendency to form a loose
spire, so that the whorls are often disunited, and do not rest
one on another.

1. VERMETUS *.

Shell thin, tubular, loose spiral; spire adhering by the apex.
Aperture orbicular, margins united. Operculum cartilaginous.

This shell has great resemblance to a serpula; its animal,
however, is not one of the annulata, but a true molluscum, and
properly placed with the trachelipoda. (See Adanson’s Senegal,
Pl. xi. fig. 1. Vermetus.) The vermeti are commonly found in
groups, twisted together.

One Species. Vermetus lumbricalis t.

Shell attached by the apex of the spire, extended anteriorly
into an ascending tube, thin, transparent, reddish yellow.
Senegal. Pl. VIII. Fig. 161.

2. ScaLaRtia ft.

Shell sub-turrited, spire more or less elongated, last whorl
rather larger than the penultimate ; ribs longitudinal, elevated,
interrupted, sub-acute. Aperture nearly round; marg'ns cir-
cularly united, and terminated by a thin curved varix.

Type. Scalaria pretiosa§. (Turbo scalaris, Linn.)

Shell conical, umbilicated, loose, spiral, pale yellow; ribs
white ; whorls disunited, smooth, the last ventricose. Indian
Seas. Pl. VIII. Fig. 162.—7 recent species, and 3 fossil.

3. DELPHINULA ||.

Shell subdiscoidal, or conical, umbilicated, solid, internally
pearly, whorls of the spire rough, or angular. Aperture entire, ,
round, sometimes triangular ; margins united, generally fringed
or varicose.

Distinguished from turbo, by the united margins.

* From vermis, a worm. + From lumbricus, an earth-worm.
t From scala, a flight of steps. § Costly, precious.

|| Dim. from delphinus, a dolphin.

252 Lamarck’s Genera of Shells.

Type. Delphinula laciniata*. (Turbo delphinus. Linn.)

Shell subdiscoidal, thick, transversely rudely sulcated ; fur-
nished with very large, curved, ramose, jagged appendages ;
variegated with red and brown; spire obtuse. Indian Ocean.
Pl. VIII. Fig. 163.—3 recent species, and 7 fossil.

10th Family.
TurBINACEAt. (8 Genera.)

Shell turrited or conoidal; aperture round or oblong, not
dilated ; margins disunited.

All sea-shells, and appear to be operculated. When placed
on their base, the axis is always more or less inclined, never
vertical.

1. Solarium tf.

Shell orbicular, depressed conical; umbilicus open, always
crenate or toothed on the internal margins of the whorls.
Aperture subquadrangular ; no columella.

The crenate umbilicus of the solarium sufficiently distin-
guishes it from the trochus and planorbis.

Type. Solarium perspectivum§. (Trochus perspec-
tivus. Lznn.)

Shell orbicular, conoidal, longitudinally striated, whitish
yellow ; bands articulated with white and brown, or chestnut
colour near the sutures; crenations of the umbilicus very
small. Indian Ocean. PI. VIII. Fig. 164. 7 recent species,
and 8 fossil.

2. Rotella|j.

Shell orbicular, shining, no epidermis; spire very short,
subconoidal; lower face convex, callous. Aperture semi-
circular.

Distinguished from trochus by the lower surface being
remarkably callous, and from the helicina by the callous not
being confined to the columellar lip, but extending over a-
large portion of the lower side of the shell. |

Type. Rotella lineolata%. (Trochus vestiarius. Linn.)
* Jagged. + From turbinatus, fashioned like a top?
t A sun-dial. § Perspective.

|| A very small wheel. q Marked with little lines.

Lamarck’s Genera of Shells. 203

Shell orbicular, convex, conoidal, very smooth, pale flesh-
colour ; numerous undulated, brown, longitudinal lines ; whorls
contiguous ; lower face white. Mediterranean. Pl. VIII. Fig.
165. 5 Species.

3. Trochus*.

Shell conical, spire elevated, sometimes rather depressed ;
periphery more or less angular, often thin and acute. Aperture
depressed transversely; margins disunited at the upper part.
Columella arched, more or less prominent at the base. An
operculum.

Many trochi have a brilliant pearly surface, and several
have longitudinal ribs, which, we believe, are never found in
the turbo.

Type. Trochus imperialist. (Idem. Gmel.)

Shell orbicular-conoidal, apex obtuse, brown inclining to
violet above, white below; transverse furrows, imbricate-
squamose ; whorls convex, turgid, radiated with a squamose
margin; squamz complicate; umbilicus funnel-shaped.—South
Seas. Pl. VIII. Fig. 166. 69 Species.

4. Monodontaf.

Shell oval or conoidal. Aperture entire, round; margins
disunited at the upper part. Columella arched, truncated at
the base. Operculum orbicular, thin, horny.

Distinguished from trochus chiefly by the more circular form
of the mouth; from turbo by the columella being truncated at
the base, and forming a characteristic dentiform projection in
the aperture.

Type. Monodonta pagodus§. (Turbo pagodus.. Linn.)

Shell obliquely conical, imperforate, tubercuiar, ribbed longi-
tudinally, transversely furrowed, brownish grey; ribs termi-
nating in long, compressed tubercles beyond the margin of
the spires ; lower face white, with concentric furrows, pimpled.
Indian Ocean. PI. VIU. Fig. 167. 25 Species.

5. Turbo|l.
Shell conoidal, or subturrited ; periphery never compressed ;

* A child's top. + Imperial.
t From eoves one, and odu¢ a tooth, § Pagoda. || A wreath,

254 Lamarck’s Genera of Shells.

whorls always round. Aperture entire, round, not disturbed
_ by the penultimate whorl; lips disunited at the upper part,
columella arched, flattened, not truncated at the base. An
operculum.

The axis of the shell is generally more inclined than that of
the trochus.

Type. Turbo marmoratus*. (Idem. Linn.)

Shell subovate, very ventricose, imperforate, smooth, marbled,
or subfasicated with green, white and brown; last whorl trans-
versely nodular, in three directions ; upper nodules largest ;
base of the lip expanded, caudate; mouth silvery. Indian
Ocean. PI. VIII. Fig. 168. 34 Species.

6. Planaxis f.

Shell oval-conical, solid. Aperture oval, sublongitudinal-
Columella flattened, truncated at the base, separated from
the right lip by a narrow sinus. Interior face of the right lip
furrowed or striped, with a callus running under its summit.

The planaxis is distinguished from phasianella by the trun-
cation of the columella; it is transversely furrowed externally,
and generally of small size.

Type. Planaxis sulcatat.

Shell ovate-conical, imperforate, transversely sulcated, white,
spotted with black; spots subquadrate; margin of the lip
crenate; internally striated. Antilles. Pl. VIII. Fig. 169.

2 Species.
7. Phasianella§.

Shell oval or conical, solid; the last whorl much larger
than any of the others, Aperture entire, oval, longitudinal,
inclined obliquely towards the base of the columella, round at
the lower part, and contracted at the upper; lips disunited at
the upper part; right margin acute, not reflected. Columella
smooth, compressed, attenuated at the base. Operculum cal-
careous or horny.

Generally smooth, brilliant shells, without any epidermis,
and ornamented with various lively colours.

* Marbled. ' + Flattened axis? t Furrowed.
§ Dim. from Phasianus, a pheasant.

Lamarck’s Genera of Shells. 255

Type. Phasianella bulimoides*. (Buccinum australe.
Gimel.)

Shell oblong-conical, rather thin, smooth, palish yellow,
transversely fasciated; fascie numerous, variously variegated
and spotted ; apex of the spire acute, New Holland. Pl. VIII.
Fig. 170. 10 Species.

8. Turritellat.-

Shell turrited, not pearly. Aperture rounded, entire, margins
disunited at the upper part, not reflected outwards; a sinus in
the right lip. Operculum orbicular, horny.

Distinguished from turbo by the general form of the shell,
and by the sinus on the right lip, a constant character. Most
of the species are transversely carinated or striated, but none
of them have vertical ribs, varices, or tubercles.

Formerly all the turrited shells were called screw shells.
Thus turritella, scalaria, cerithium, &c., were all confounded
with the true screw shell, terebra.

Type. Turritella duplicatat. (Turbo duplicatus. Linn.)

Shell -turrited, thick, heavy, transversely sulcated and ca-
rinated, whitish yellow, apex reddish; whorls convex, cari-
nated; the two middle carine most prominent. Coast of Coro-
mandel. Pl. VIII. Fig. 171. 13 recent Species, and 2 fossil §.

Sectron II.

TRACHELIPODA with a projecting siphon. (Zoophagal|.)

The animals of this section breathe only water, which is
conveyed to the branchize by the projecting siphon. They are
all carnivorous, marine, without jaws; and have a retractile
proboscis. Two tentacula on the head.

Shell spirivalve, ensheathing, aperture canaliculated or
notched, or merely inclined at the base.

* Resembling a bulimus. + Dim. from turris, a litile tower.

+ Doubled, because it is bi-carinated.

§ Desmarets has described a new genus, established by Freminville
which we shall add in this place. It has been called Rissoa; we give a
figure of one species.

Shell univalve, oblong or turrited, generally furnished with prominent
longi udinal ribs, aperture entire, oval, oblique; no canal at the base ; no
tooth, nor plait ; margins united, or nearly united ; right margin inflated, not
reflected. No umbilicus. Gulf of Genoa. Fig. 172. (Vide Nouveau Bul-
letin des Sciences, or Nouveau Dictionnaire d’ Histoire Naturelle.)

|| Carnivorus.

Vou. XV. Ss

256 Lamarck’s Genera of Shells.

This section contains five families ; in the two first the canal
at the base of the aperture is always manifest; in the third it
disappears, and the two last have only a notch, and a small,
low, inclined margin,

Ist Family.
CANALIFERA. (11 Genera.)

Shell with a canal, variable in length, at the base of the

aperture, the right margin of which does not alter by age. An

operculum.
This family is separated into two divisions.

Ist Division.
No constant varix on the right lip.

1. Cerithium *.
Shell turrited. Aperture short, oblong, oblique, terminated at
the base, by a short truncated or curved canal; never notched.
A slight channel at the upper extremity of the right lip. Oper-
culum small, orbicular, horny.

The spire of the shell constitutes at least two thirds of its
whole length; the last whorl being but little larger than the
preceding one, the shell has the form of an elongated pyrami-
dal cone ; surface generally striated or tubercular, and some-
times varicose.

A thorough knowledge of this numerous genus is very im-
portant to the modern geologist.

Type. Certthium palustret. (Strombus palustris. Linn.)

Shell turrited, thick, longitudinally plicate, transversely stri-
ated, brownish ; whorls tri-striated, the last with very numerous
sulciform striz; lip sub-crenate.

East Indies. Pl. VIII. Fig. 173. 36 recent species, and 60
fossil.

2. Pleurotoma ¢.

Shell turrited, or fusiform, terminated at the lower part by a

* From Cerites, « gem of a waxen colour 2

+ Of the marshes ; Lamarck’s 2d genus; his type is C. giganteum.

t From masuea, the side, and rey» to cut, denoting the characteristic fissure
on the right lip.

Lamarck’s Genera of Shells. 257

straight canal, more or less elongated. A fissure or sinus in
the upper part of the right lip. Operculum oblong, horny.

Type. Pleurotoma Babylonica*. (Murex Babylonius. Linn.)

Shell fusiform, turrited, transversely carinated, and banded,
white; bands spotted with black, spots quadrangular; whorls
convex; base rather long.

Indian Ocean. Pl. VIII. Fig. 174. 25 recent species, and 30
fossil.

3. Turbinella +.

Shell turbinate, or subfusiform, channelled at the base ; from
three to five compressed, transverse folds on the columella.

Distinguished from voluta, by the canal at the base of the
aperture; from murex by having no varices, and from fascio-
laria by the direction of the folds on the columella.

Type. Turbinella cornigeraj. (Voluta turbinellus. Linn.)

Shell ovate-turbinated, subtriangular, transversely sulcated,
with white turbercles on every side ; interstices of the tubercles
black ; upper part of the last whorl surmounted by thick elon-
gated tubercles, trifurcate posteriorly, and near the base, muri-
cated with other simple tubercles ; spire very short, acuminated ;
columella quadriplicate.

Indian Ocean. Pl. VIII. Fig. 175. 23 Species.

4, Cancellaria §.

Shell oval or turrited. Aperture sub-canaliculate at the base ;
canal very short or scarcely perceptible. Columella plaited ;
folds numerous or few, generally transverse ; right lip sulcated
internally.

Type. Cancellaria reticulata||. (Voluta reticulata. Linn.)

Shell ovate, ventricose, perforate, thick, transversely rugose,
reticulated with oblique longitudinal strie, slightly marked with
yellowish white, and red zones; whorls convex; sutures com-
pressed ; upper part of the columella smooth, lower portion
triplicate.

South Atlantic Ocean, Pl. VIII. Fig. 176. 12 recent species,
and 7 fossil.

: pervenian. peourchs 17th species. His type is P. imperialis.

+ Horned. Lamarck’s 7th species ; his type is T. scolymus.
§ From cancelli, latices ? || Reticulated,

S 2

258 Lamarck’s Genera of Shells.

5. Fasciolaria *.

Shell subfusiform, channelled at the base, no varices; two
or three very oblique folds on the columella, near the canal,

Distinguished from fusus by the folds on the columella, and
from turbinella by their oblique direction.

Type. Fasciolaria tulipa+. (Murex tulipa. Linn.)

Shell fusiform, ventricose in the middle, smooth, reddish
orange-coloured, or marbled with white and red; brown trans-
verse lines at unequal distances; whorls very convex; sutures
marginally fringed ; base sulcated; lip internally white, striated.

Antilles. Pl. VII. Fig. 177. 8 Species,

6. Fusus f.

Shell fusiform, or subfusiform, channelled at the base; yven-
tricose in the middle, or lower part; no external varices; spire
elevated and elongated; no fissure or sinus in the right lip.
Columella smooth. Operculum horny.

Type. Fusus colus§. (Murex colus. Linn.)

Shell fusiform, narrow, transversely sulcated, white; apex
and base red; belly small; whorls convex, nodular carinate in
the middle; base slender, long ; lip sulcated internally, margin
toothed.

Indian Ocean. PI. VIII. Fig. 178. 37 recent species, and

13 fossil.
7. Pyrula. ||

Shell subpyriform, channelled at the base, ventricose at the
upper part; no external varices; spire short, sometimes flat-
tened, columella smooth. No fissure on the right lip.

The pyrula differs widely from fusus, by its short spire, and
by the remarkable inflation of the last whorl, being always at
the upper part of the shell.

Type. Pyrula canaliculata% (Murex canaliculatus. Linn.)

Shell pyriform, ventricose, thin, rather smooth, palish yellow ;
upper part of the whorls angular, with flattened tops ; channels
of the sutures distinct ; angle of the upper whorls crenate ; base
rather long.

Canada. PI. VIL. Fig. 179. 28 Species.

* From fasciola, a little band. + A tulip. {A spindle.

§ A distaff, Lamarck’s third species ; his type is F. colosseus.
|| Dim. from pyrum, a pear. | Channelled.

209

Art. V. On the native Country of the Wild Potato,
with an Account of its Culture in the Garden of the
Horticultural Society; and Observations on the Im-
portance of obtaining improved Varieties of the cul-
tivated Plant*. By Joszru Sasine, Esq., F.R.S., &c.

Tue possession of the plants of the Native Wild Potato has
been long a desideratum, and from the great importance and
extensive use of the cultivated root, the subject of course became
an object of attention to the Horticultural Society. In my com-
munications with the Society’s correspondents on the other side
of the Atlantic, this was pointed out as one of the most interest-
ing objects to which their attention could be directed ; and it is
with no small satisfaction that I am able to state that our in-
quiries have been successful.

Great doubts have existed as to what parts of the new world
the natural habitat of the Solanum tuberosum or Potato should
be assigned; and the question is even now a matter of discus-
sion among Botanists of the greatest eminence. The vegetable,
in its cultivated state, was first known in this country as the Po-
tato of Virginia; I conceive, however, there can be little doubt
that the plants which Sir Walter Raleigh found in that colony,
and transferred to Ireland, had been previously introduced there
from some of the Spanish territories, in the more southern parts
of that quarter of the globe; for had the potato been a native
of any district, now forming part of the United States, it would
before this time have been found and recognised by the botanical
collectors who have traversed and examined those countries.

From the Baron de Humboldt’s observations on the potato
in Mexico+, it seems certain that it is not wild in the south-
western part of North America; nor is it known otherwise than
as a garden plant in any of the West India islands. Its exist-
ence, therefore, remains to be fixed in South America, and it
seems now satisfactorily proved, that it is to be found both in
elevated places in the tropical regions, and in the more tem-

+ oom the Horticultural Transactions.

sysgy red on the Kingdom of New Spain. Black’s Edition. Vol.
un page 484,

260 On the Native Country of the Wild Potato, &c.

perate districts on the western coasts of the southern part of
that division of the new world.

According to Molina*, it grows wild abundantly in the fields
of Chili, and in its natural state is called by the natives Maglia,
producing, when uncultivated, small and bitter tubers. The
Baron de Humboldt asserts, that it is not indigenous in
Peru, nor on any part of the Cordilleras situated under the
Tropics. But this statement is contradicted by Mr. Lambertf,
on the authority of Don Jose Pavon and of Don Francisco Zea;
the former of whom says, that he and his companions, Dombey
and Ruiz, had not only gathered the Solanum tuberosum wild in
Chili, but also in Peru, in the environs of Lima; and the latter
has assured Mr, Lambert, that he had found it growing in the
forests near Santa Fé de Bogota. The above account of Pavon
is further confirmed by the evidence of a specimen gathered by
him in Peru, and now forming a part of the herbarium of Mr.
Lambert, with the name of “ Patatas del Peru.”

Mr. Lambert, in his communication to the Journal of Science
and the Arts, which I have referred to, supposes that the wild
potato is to be found on the eastern, as well as the western and
northern sides of South America. His opinion on this point
appears to have been founded on the following circumstances :

Among the specimens in the Herbarium formed by Commer-
son, when he accompanied Bougainville in his voyage round the
world, is one of a Solanum, gathered near Monte Video. In the
Supplement to the Encyclopédie, (Vol. IIL. p. 746), this specimen
was described, on the authority of M. Dunal of Montpelier, as
belonging to a species distinct from Solanum tuberosum, under
the name of Solanum Commersonii, and it was subsequently
published by M. Dunal, with the same name in the Supplement
to his Solanorum Synopsis§. (The article from the Encyclopédie
is given below||). Mr. Lambert, however, conjectured this spe-

* Hist. Nat. du Chili, p. 102.
+ Political Essay on the Kingdom of New Spain. Black’s Ed. Vol. II. p. 489.
t Journal of Science and the Arts. Vol. X. page 25. § Page 5.
| Morelle de Commerson. Solanum Commersonii. Solanum caule her-
baceo, piloso ; foliis pinnatis sublyratis, pilosis: floribus corymbosis, ter-
minalibus ; pedicellis articulatis, Dun, Suppl. Sol. MSS,
Toute

On the Native Country of the Wild Potato, &c. 261

cimen to be that of the type of the cultivated potato, and was
induced to do so by information received from Mr. Baldwin, an
American botanist, that he had found the Solanum tuberosum
wild, both at Monte Video, and in the vicinity of Maldonado, as
‘well as from Captain Bowles, who had resided a considerable
time at Buenos Ayres, and who had told him that this plant was
a common weed in the gardens and neighbourhood of Monte
Video.

The above statements certainly confirm the existence of a
plant in sufficient abundance near the shores of the Rio de la
Plata, which Mr. Lambert identifies with Commerson’s speci-
men; but the proof that it is the Solanum tuberosum, in oppo-
sition to the decision of Mr. Dunal, rests only on the opinion of
Dr. Baldwin, and Captain Bowles, without the usual satisfactory
evidence of specimens, which have not been supplied by either
of these gentlemen.

In order to elucidate the question as much as possible, I
applied to M. Desfontaines, Director of the Museum of Natural
History in the Jardin du Roi at Paris, for permission to have a
drawing made of Commerson’s original specimen, which was
deposited in the Herbarium under his charge. With a liberality
and kindness which I cannot too highly compliment, the en-
tire specimen was, without delay, transmitted to me. It has
much the appearance of being in a dwarf or stunted state.
The label affixed to it is thus described: “ Hispanis To-
mates—flores sunt palliduli—de la plage du pied du Morne
de Monte Video en Mai, 1767.” The size of the blossom is
evidently larger than that of the S. tuberosum, under similar
circumstances ; the depth of the divisions of the flowers, and the
larger proportional size of the terminal leaf, present striking
differences from correspondent parts of the common potato.

Toute la plante est converte de poils simples ; elle a les plus grands rap-
orts ayec le Solanum tuberosum; elle en differe, 1°. par ses feuilles pro-
ondement pinnatifides comme celle de la Pomme de terre, mais dont les

folioles sessiles ne sont pas alternativement inégales. 20°. par Ja foliole im-
paire, qui est tres grande. 3°. par la corolle, qui est acing divisions non a
cing angles. La racine de cette plante est encore inconnue.

262 On the Native Country of the Wild Potato, &c.

Very little hairiness is perceptible on the specimen, which, if it
had been taken from a plant of S. tuberosum, would probably
have been much more hairy, as it usually is when stunted. It
is also somewhat singular that Commerson, who could not but
know the S. tuberosum and its various names, should have
affixed that of “« Tomates’’ to his specimen ; this makes it almost
certain that he did not consider it to be the potato. On these
grounds I have ventured to hesitate in concurring in the opinion
of Mr. Lambert, that we have sufficient evidence of the growth
of the wild potato in the neighbourhood of the Rio de la Plata.
It possibly may be found there, but its existence in that part of
America is not proved, since it seems tolerably certain that
Commerson’s plant is not it, and Mr. Lambert does not suppose
that the plants seen by his correspondent and friend were
different from Commerson’s.

Early in the spring of the present year, Mr. Caldcleugh, who
had been some time resident at Rio Janeiro, in the situation of
Secretary to the British Minister at that Court, where he had
been indefatigable in his exertions to forward the objects of the
Horticultural Society, returned to England, having previously
taken a journey across the country, and visited the principal
places on the western coasts of South America. Among many
articles of curiosity which he brought with him, were two tubers
of the wild potato, which he sent to me with the following
letter :

Montague Place, Portman Square, February 24th, 1823.
My DEAR Sir,

Ir is with no small degree of pleasure that I am enabled to
send you some specimens of the Solanum tuberosum, or Native
Wild Potato of South America.

It is found growing in considerable quantities in ravines in
the immediate neighbourhood of Valparaiso, on the western
side of South America, in lat. 345S. The leaves and flowers
of the plant are similar in every respect to those cultivated in
England, and elsewhere. It begins to flower in the month of
October, the spring of that climate, and is not very prolific.

On the Native Country of the Wild Potato, §c. 263

The roots are small and of a bitterish taste, some with red and
- others with yellowish skins. 1 am inclined to think that this
plant grows on a large extent of the coast, for in the south of
Chili it is found, and called by the natives Maglia, but I cannot
discover that it is employed to any purpose.

I am indebted for these specimens to an officer of His Ma~
jesty’s ship Owen Glendower, who left the country some time
after me.

I am, my dear Sir, ever sincerely youtr’s,

ALEXANDER CALDCLEUGH.

The two tubers were exhibited to the Society, and a drawing
made of them before they were planted. Had there been a third,
I should have been tempted to have satisfied myself as to the
real flavour, which Mr. Caldcleugh, as well as Molina, describes
as bitter. They were planted separately in small pots, and
speedily vegetated; they grew rapidly, and were subsequently
turned out into a border at about two feet distance from each
other, when they became very strong and luxuriant. The blos-
soms at first were but sparingly produced, but as the plants were
earthed up they increased in vigour, and then bore flowers
abundantly ; but these were not succeeded by fruit. The flower
was white, and differed in no respect from those varieties of the
common potato which have white blossoms. The leaves were
compared with specimens of several varieties of the cultivated
potato, which generally were rather of a more rugose and un-
even surface above, and with the veins stronger and more con-
spicuous below, but in other respects there was no difference
between them. The pinnule which grew on the sides of the
petiole, between the pinnze of the leaves, were few, not near so
numerous as in some varieties of the cultivated potato; but in
specimens of other varieties that were examined, their leaves
were destitute of pinnule, so that the existence of these ap-
pendages does not appear to be so essential a characteristic as
has been supposed, and as is stated in the Supplement to the
Encyclopedie.

The earth with which the plants had been moulded up had

264 On the Native Country of the Wild Potato, &c.

been applied in considerable quantity, so as to form a ridge, the
sides of which were full two feet high; and about the month of
August, runners from the roots and joints of the covered stems
protruded themselves towards the surface of the ridge in great
numbers, and when they reached the light, formed considerable
stems, bearing leaves and blossoms, so that at length the two
plants became one mass of many apparently different plants
issuing from all sides of the ridge. The appearance of these
runners in such quantities induced a doubt as to the identity of
the plant with our common potato, which doubt was increased
when it was ascertained, that so late as the month of August no
tubers had been formed by the roots. The runners were, how-
ever, no otherwise different from what are formed by the cul-
tivated potato under ground, except that they were more
vigorous, as well as more numerous.

The plants have recently been taken up, and all doubt re-
specting them is now removed; they are unquestionably the
Solanum tuberosum. ‘The principal stems, when extended,
measured more than seven feet in length; the produce was most
abundant, above six hundred tubers were gathered from the two
plants; they are of various sizes, a few as large or larger than
a pigeon’s egg, others as small as the original ones, rather
angular, but more globular than oblong ; some are white, others
marked with blotches of pale red or white. The flavour of them
when boiled was exactly that of a young potato.

The compost used in moulding up the plants was very much
saturated with manure, and to this circumstance [I attribute the
excessive luxuriance of the growth of the stems; had common
garden mould been applied, they would not probably have
grown so strong, and I suppose that whilst the plants were
thus rapidly making stems and leaves, the formation of the
tubers was delayed, for the production of these has been the
work of the latter part of the season; they cannot be called
fully ripe, nor have they attained the size which they probably
might have done if they had been formed earlier.

They will, however, answer perfectly for the purpose of re-
production (or for seed, as it is technically called), and they are

On the Native Country of the Wild Potato, Sc. 265

in sufficient plenty to be subjected to treatment similar to a
common crop of potato. The result of another year’s ex~-
perience is necessary to enable us fully to observe on the merits
and value of this new introduction; but the following changes
already appear to have attended its subjection to cultivation;—
the produce is most abundant, the tubers have lost all the
bitterness of flavour which is attributed to them in the natural
_ state, and their size is increased remarkably; from all which
circumstances I am disposed to infer, that the original culti-
vators of this vegetable did not exercise either much art or
patience in the production of their garden potatoes.

The increased growth of the potato, not only in these king-
doms, but almost in every civilized part of the globe, has so
added to its importance, that any information respecting it has
become valuable ; the subject of this communication may there-
fore not be without interest. With the exception of wheat and
rice, it is now certainly the vegetable most employed as the food
of man; and it is probable that the period is at no great distance,
when its extensive use will even place it before those which have
hitherto been considered the chief staples of life. The effect, of
the unlimited extent to which its cultivation may be carried, on
the human race, must be a subject of deep interest to the poli-
tical economist. The extension of population, will be as un-
bounded as the production of food, which is capable of being
produced in very small space, and with great facility ; and the
increased number of inhabitants of the earth will necessarily
induce changes, not only in the political systems, but in all the
artificial relations of civilized life. How far such changes may
conduce to, or increase the happiness of mankind, is very pro-
plematical; more especially when it is considered, that since the
potato, when in cultivation, is very liable to injury from casu-
alties of season, and that it is not at present known how to keep
it in store for use beyond a few months, a general failure of the
year’s crop, whenever it shall have become the chief or sole
support of a country, must inevitably lead to all the misery of
famine, more dreadful in proportion to the numbers exposed to
its ravages.

266 On the Native Country of the Wild Potato, §c.

Under such circumstances, and with such a prospect, it is
surely a paramount duty of those who have the means and
power of attending to the subject, to exert themselves in select-
ing and obtaining varieties of potatoes, not only with superior
qualities in flavour and productiveness, but which shall be less
subject to injury by changes of weather when in growth, and
which may possess the quality of keeping for a length of time,
either in their natural state, or under the operation of artificial
treatment. This is one of the objects to which the care and
energies of the Horticultural Society ought to be directed.
Under its auspices, and by its means, some new kinds have been
brought into notice, but a wide field of exertion is still before it.
With the potatoes cultivated in South America at the present
time we are very little acquainted ; there is one especially which
has been heard of, but which has not yet reached us, known at
Lima as the yellow or golden potato, and which is reported
to be far superior in flavour to any now grown in Europe.

On the subject of the potato there is also a point of curiosity
and much interest open to those who have leisure and opportu-
nity of conducting the investigation. Several accounts of its
introduction into Europe, and especially into Great Britain and
Ireland, are before the public, differing from each other, and
none exactly correct; the entire truth is probably to be extracted
from the whole, and ought to be supported by references to the
original authorities for the different facts. To these, in order
to render the early history of the potato complete, an account
of its original discovery, and the observations made on it by
the first and early visitors to the shores of South America,
should be obtained; and this research would probably lead to
a detection of the circumstances attending its first introduction
into Virginia, which is at present involved in obscurity.

267

Art. VI. Observations on the Project of taking down
and rebuilding London Bridge.
[By a Correspondent. ]

Ir is a matter certainly of great interest to men of science, to
know what effect the removal of a dam producing a fall of
water westward at high water sometimes of two feet, and east-
ward at low water sometimes of nine feet, from a great river
like the Thames, would have westward and eastward of that
dam in respect to the bed and shores of such a river; and whe-
ther a more frequent inundation and saturation with water of
the low lands will cause miasms and pestilential diseases again
to prevail, should the means of stopping such inundations
or of quickly draining off the water not be immediately ob-
tained. They look forward with great anxiety to the expe-
riment; and the knowledge that this dam has existed many cen-
turies, that the river passes through a dense population, that
the estates of individuals have been regulated by it, that the
levels of the lowest floors of houses and those of the streets in
the low lands adjacent, have reference to this habit of the river,
adds much to the excitement; for the intenseness of the interest
always increases with the hazard of the throw. The complaints
of the inhabitants on the banks of the river, like those of the
dumb creature subject to the knife of the surgeon, are not
heard in the eager pursuit of knowledge, and in the speculation
of future amelioration. There are others who have great
influence, and are urgent for the demolition of London Bridge,
looking to their own gain in the erection of a new one.
A mathematician, like to him of Laputa, has brought his im-
plements to the question, and, without sections, without levels,
and ignorant of the soil over which the river flows, or against
which it impinges at its sinuosities, knowing neither what may
be overflowed, nor what may be sapped, has, by a kind of
intuitive philosophical tact, determined that, after the removal
of the dam, the stream will flow on as harmless and obedient
as heretofore*. Presuming there may be some of your readers

_ * See Dr. Hutton’s Answers, App. 4th Report, 1821.

268 Observations on taking down and

unable to discover truth except by induction, and others costive
of their belief in the delirations even of a great teacher, and
thinking that they may be desirous of viewing this important
question by any glass, however weak its power, your corre-
spondent ventures to offer that by which he views the question,
and solicits the shelter of a few pages for the following observa-
tions in your journal.

The writers on the ordinances of rivers consider the courses
and velocities of them dependent on the nature of the ground
over which they pass, as well as upon the heights from which
their waters descend. For example, water descending from a
height on rocky ground, which it cannot remove, rises, spreads,
and forms a lake; and proceeds with diminished velocity to
the lowest point, and there cascades ; advancing at the rate of
forty-five inches per second, it will drive flint stones about the
size of an egg before it, and rise and spread until its velocity is
reduced to thirty-six inches per second, when the stones
remain at rest; proceeding among pebbles about an inch dia-
meter, it serves them the same, rising and spreading until its
velocity is reduced to twenty-four inches per second, when they
remain at rest; proceeding through coarse gravel about the
size of a marble, it serves it the same, rising and spreading until
its velocity is reduced to twelve inches per second; and so it
proceeds with diminished velocity according to the size of the
grain, the velocity and the course always varying with the
obstacles met with. Gravel, the grain being about the size of
aniseed, will be at rest at a velocity of four inches per second ;
sand will remain at rest at a velocity of seven inches per second,
and precipitate at six inches per second. Clay will remain at rest
at a velocity of three inches per second*. By reference to the map
of the river Thames west of London Bridge, and bearing the
above-mentioned facts in mind, it will appear that the banks
of the river from Nine Elms, a little above Vauxhall Bridge, to
London Bridge may be considered artificially fenced, and only
requiring additional aid by raising and wharfing to prevent over-

* See Principes d’ Hydrauligue, par M. le Chey. Du Buat ; Expériences sur
les Cours des Fleures, par M. Genneté ; and the article River, Ets, Brit.

rebuilding London Bridge. 269

flowing and sapping, through any increased height and velocity
of the current; and, consequently, as the waters will not be
allowed to spread in a neighbourhood where land is so valuable,
the bed of the Thames in this part must be deepened naturally
if the current acquires increased velocity; and, therefore, the
bridges in this part, especially Vauxhall and Westminster
Bridges, which do not stand upon piles, must be secured. If
proceeding from Fulham and impinging on the shore of Wands-
worth and Battersea*, the water should find the soil less
resistive than on the opposite bank of the Grove, Chelsea, and
Ranelagh, and the banks be not artificially strengthened, the
water may take a short cut at some high flood in its course to
the sea from Fulham to Nine Elms, and place Battersea in
Middlesex. The same principles will apply both to the effects
of the flood and ebb tides, from an increased velocity, at the
several bendings of the stream, and, without expensive wharf-
ings and continual care after the dam is removed, the proprie-
tors of lands on the river shores, where there are elbows, may
expect sometimes to lose a rood, and sometimes an acre of
their lands, together with their sheep and cows.

The present turbidness of the river, and the frequent shifting
of some of the banks and shoals, shew it to be now sometimes
at variance with its bed and banks. Hence it is necessary to
ascertain the nature of the soil of the bed of the river and of its
banks at the several points of sinuation up as high as Tide-end-
town, wherever it may be hereafter, whenever there are buildings
to be sapped + ; and this inquiry should be made in the survey,
which, by an extract from the report of Mr. Telford in the
Phil. Mag. of May last, he has requested authority to get made,
complaining that no such document exists; the persons ex-
amined before him since 1800 up to this session of parlia-
ment, as to the effect likely to be produced by the enlargement

* The river here is comparatively rough and rapid. The boatmen have
a story, that a band of fiddlers at this place were in former times drowned,
and that the river has been dancing here ever since. Another band are
determined to make the land join in the jig.

+ See Appendix, (A. 23, 3d Report. Lond. Port.,) in which are given
the bornings from London to Blackfriars’ Bridge, from which it appears
that the bed of the river, in that part, is gravel and sand, coarse and fine.

2x70 Observations on taking down and

of the water-way of London Bridge having been able to decide
upon these matters without the data Mr. Telford now thinks
necessary. Such a river as the Thames, which, at a mean
width between London and Blackfriars Bridges, even now the
dam exists, having a velocity in the mid stream of sixty-three*
inches per second, or 3,6, miles per hour, at half flood, requires
some respect to be paid to its speed, its windings, and its
fences, and will be found indignant to an alteration of its ancient
habits. The paradoxes which experiments on the flowing of
waters present, the recent history of the Eau Brink as to its antici-
pated and its actual effect on the harbour of Lynn, the erroneous
calculations of the Royal Academy of Paris in respect to the
apparently simple question of the Paris aqueduct, and those of
Desaguliers and M‘Laurin as to that of Edinburgh, might cause
some doubt of any opinion with sufficient data, and much more
of the determinations of mere theory, from one of very advanced
age, without any. The question relating to the effects of the
removal of the dam westward, put in the following manner,
would cause more inquiry than the present seems to have
done.

What effect would the introduction of another river on the
west side of London Bridge, of the same dimensions as the river
Thames at London Bridge, with a fall into it of two feet, have
upon the bed and banks westward at high water? What effect
would the subtraction of aquantity of water, at low water, equal to
the surface of the river, six feet in depth at that subtraction, have
upon the river westward at that time of the tide? It has been main-
tained, with reference to a compensation clause in the bill for the
new bridge, that, in cases of land-floods, the removal of the dam
of London Bridge would not cause an increased height of the
waters in the up country, but have a contrary effect. This position
is true at all times of the ebbing, but not of the flowing; a high
sea-flood meeting a high land-flood must dam back the latter,
and at times two feet higher than at present, when the dam of
the bridge is removed. For example, on the 28th of December,

* See 3d Report, Appendix. G. London Port, and Plate 20, ADPEEA-

At Westminster, Mr. abelye ascertained the velocity to be thirty-six
inches per second.

rebuilding London Bridge.’ 971

1821, from the freshes, the whole of the up-country was so
flooded that the inhabitants of the low-lands adjacent used
boats in the streets ; a sea-flood meeting such a flood, and suf-
fered to rise two feet higher than it can at present, would have
caused a greater extent of country to be flooded than suffered
at that time *.

Those who favour the removal of the dam of London Bridge,
should, during the present hot weather, take a boat at low
water from London Bridge, and proceed up the river; and,
whilst they enjoy the odour from the banks, contemplate the
effects of lowering the water from four to six feet, consequent
on such removal, occasionally requiring the boatman to sound
the depth with his oar; it will then be manifest to them what a
stinking ditch the river will become at low water. Though an
expenditure of a large sum of money might dredge out a tem-
poral channel for the navigation at that time, it must neverthe-
less be remembered, that the width of the river increases up-
wards from London Bridge, and there are no moveable dams,
for which purposes the ships below London Bridge are used to
keep it clear. The cause assigned for taking down London
Bridge is as follows; ‘“ Whereas the great fall of water at
certain times of the tide, occasioned by the large starlings and
piers of the said bridge, renders the navigation through the
said bridge dangerous and destructive to the lives and proper-

* The late Mr. Mylne’s Report, Appendix (A 1) and Plate 1, 3d Report.
London Port, without data, but from a practical tact, confirms the opinions
contained in this paper. He was employed with a view to the demolition of
London Bridge, and was a strenuous advocate for a new one. He contem-
plates the inadequacy of the sea-walls, but leaves, like the new bill, the care
of them to the respective owners. If we may rely on the effect of the
increased velocity on the bed of the Thames, which he anticipates, there
will, soon after the dam is removed, be the materials of two or three
bridges ready wrought at London Bridge for the new stracture, without the
trouble of stopping the receipts of the excise and customs of the three
kingdoms. The fall of water, westward of London Bridge, has dug out
the bed of the river, to a distance of four hundred feet, of twenty-eight feet in
depth at the lowest point; and that, eastward from the ebbing and freshes,
has dug out the bed of the river to a distance of six hundred feet, of
thirty-four feet in depth below the bed at the lowest point; when the dam
of the bridge is removed, this power will be principally spent in deepening
the river upwards. The maintaining Blackfriars Bridge, even with the
present bed of the river, ought to be more an object of solicitude than the
destruction of London Bridge ; its piers are in a very dilapidated state,—
and it is to be remembered that the piles under them were not driven nor
eut off within coffer-dams.

Vou. XV. T

272 Observations on taking down and

ties of His Majesty’s subjects.” By reference to the reports of
the Committees of the House of Commons, of the sessions 1820
and 1821, relating to this bridge, ordered to be printed May
and June, 1821, and upon abstracting from the evidence there-
in, relating to the loss of life and property in the last twenty
years, the promoters of the demolition of the bridge cannot
produce a statement of a greater number of persons drowned
than 17, nor damage to property exceeding 40001. by accidents
at London Bridge, during that time. The evidence, with re-
spect to the danger of the navigation through the bridge, of the
lightermen examined, many of whom have navigated the river
for forty years, is directly at variance with the opinions of those
who are desirous of a new bridge, and attributes the accidents
which occur to mere ignorance and drunkenness.

The sufficient stability of this bridge was ascertained in 1759,
when the large arch was made, and unquestionably confirmed
by the late examination of the structure of the piers *.

The sufficient width of the bridge as a roadway, is main-
tained by Mr. Rennie’s evidence, (16th April, 1821,) who, upon
being asked, “‘ What would you propose to make the width of
the new bridge?” answered, “ The same width as the old one;”
and added, London Bridge is wider than either Southwark,
Blackfriars, or Waterloo Bridges. The width of the bridge, in
the clear of the parapets, in the design which received the first
premium, is only 443 feet, a less width than between the para-
pets of the present bridge t+; so that the mechanics and trades-
men who urge the necessity of a new bridge, in the hopes of
having a freer thoroughfare for themselves and their carts, will
be grievously disappointed.

In the late application to architects and engineers, it seems
remarkable, that it had not occurred to the bridge committee,

* Appendix, Report on London Bridge, 1821, p. 66, &c.

+ See Mr. Dance’s section, Append. B.1. 2d Report, London ‘Port. By
Append. B. Ill. 3d Report, London Port, London Bridge is 45 feet wide,
Blackfriars 41 feet, Westminster 39 feet 9 inches.

The late Mr. Mynie (App. B. IL.) thought 50 feet a proper width for the
new London Bridge. The roadway of Waterloo Bridge is 28 feet, the foot-
paths each seven feet, together 42 feet ; the same as Westminster Bridge is
stated to be by Mr. Labelye. Vauxhall Bridge has a roadway of 28 feet,
and two footpaths of 5 feet 6 inches each, together 20 feet.

rebuilding London Bridge. 273

that the supposed evil might have another remedy than a new
bridge ; and out of the course of ordinary proceeding. It might
have suggested itself to some engineer, contemplating the direc-
tion of the mid stream of the Thames towards Pepper-alley
stairs, and the bank of gravel that directs it in that course; or
to some antiquary, who recollected King Canute’s mode of con-
veying his fleet from the east side to the west side of London
Bridge; or the direction of the cut which was made in 1173,
when this bridge was rebuilt,—that an auxiliary cut, and bridge,
round the foot of the present structure, north of Tooley-street,
might be a cheaper mode of obtaining the proposed object than
a new bridge; especially upon finding, upon inquiry, that be-
tween the linear waterway (690 feet) required, and the abso-
lute linear waterway of the present bridge, (545 feet,) there is
only a deficiency of 145 feet; and between the superficial water-
-way of London Bridge, and that of the section of the whole
river, from Old Swan-stairs to Pocock’s Flour wharf, at high
water, there is only a deficiency of about 4000 feet.

Others, deprecating the removal of the dam, but desirous
of rendering the navigation, even when intrusted to unskilful
and drunken lightermen, safe, and accustomed to view the
locks on other rivers, and even upon this, may surmise, that
the object might be obtained by locks *.

The cost of the repairs of this bridge annually, for the twenty
years previous to 1818, varied between 6027/. and 1455. The
income of the estates applicable to the repairs of the bridge, for
1818, is stated to be 26,526/., of which about 11,000/. were
expended in management. The trustees, also, possessed stock

* Had the instructions to these candidates been unfettered, there might
have been a renewal of Messrs. Douglas and Telford’s scheme for a cast-
iron bridge of 600 feet span, with a rise of 65 feet above high water, for

' yesselS to sail above London Bridge, and only at the cost of 262,289.
The practicability and advisableness of this bri ge was certified by twelve
out of fifteen mathematicians and engineers, though, at that time, neither
the designers, nor the committee, nor any of the mathematicians or engi-
neers, knew the strength of cast iron ; and those who supposed they knew
‘something of the matter, thought it forty times stronger than it since has
been found to be: so easy is it to ask and receive opinions. But where a
favourite object is to be carried, the data, upon which such opinions must
‘be founded, are kept out of sight or misstated or an inquiry into them is
refused. :

T2

274 Observations on taking down and

and cash to the amount of 112,000. It was intended that the
corporation of London should take up the money, for the pur-
poses of the new bridge, on the security of the Bridge House
estates; but as they only produce an annual income of about
26,000/., of which 11,000/. are required for management, there
only remained 15,0002. per annum to pay the interest of money
to be borrowed ; and allowing the appropriation of a part gra-
dually to pay off the principal, it became manifest, that the
estates would not be security for more than 250,000/., which,
added to the 112,000/. in hand, afforded from these estates only
360,000/. towards the new bridge; this sum has wonderfully
increased since 1818, so that the corporation are now able to
give 200,000/., and raise 400,000/, and reserve for manage-
ment, Sc., 12,000/. per annum. Government is to give, also,
150,000/., divided into annual payments, in seven years ; during
which time the public are to submit to the nuisance, both in
respect to the navigation, and the thoroughfare over the river.
Hence it appears, that there are about 750,000. in embryo for
the new bridge, squaring, of course, with the estimates; but, upon
referring to the bill brought into parliament this session, for
rebuilding London Bridge, there seems to have been originally
some doubt as to the sufficiency of means *; for it will be found,
that the commissioners of His Majesty’s Treasury were to be
allowed to issue exchequer bills for the approaches, and they
were also to be allowed to pay the expenses of the act, and
direct taxes were to be levied on the public, on coals and wine
imported into the city of London, for liquidating and paying
the interests of these Exchequer bills, under the scveen of what
is called the Orphans’ Fund, and indirectly, by the introduction
of a clause to exempt the corporation “‘ from the payment of any
damage to persons, or their houses, estates, vessels, or property,
by reason of the increased rise of the tide of the said river above

* The amended bill makes the doubt approach to a certainty ; for it is
said to contain a specific clause, that no one shall be entitled to compensa-
tion for any nuisance, obstruction, or injury, on account of the bridge re-
waining unfinished, in case the sum or sums of money, to be raised and ad-
vanced, prove insufficient to complete the same.

rebuilding London Bridge. 275

the said bridge, or the alteration of the channels or currents of
the said river, or of the want of water for navigating the same,
nor for any nuisance, obstruction, or injury, to be occasioned
thereby *.”

But it being understood that the direct taxes might be indi-
gestible, that part of the bill is struck out, and a less visible
mode of taxation is to be adopted, by allowing the Commission=
ers of Customs and of Excise, of England, Ireland, and Scot-
land, with consent of the Lords of the Treasury, to remit taxes
on stone, brick, timber, or other materials used in building the

‘bridge, and its appurtenances. For this purpose, the ordinary
course of government is to stop, and there is to be a particular
interposition; but the poor people, who may be ruined in their
fortunes, diseased by the damps and miasms caused by the
saturation of their habitations by frequent floods, or overwhelm-
ed by floods, from an inability to provide against them, conse-
quent on this revolution of the ancient, and now constitutional,
habit of the river, are left to the care of a higher Power, who
has set his bow in the heavens as a token. The scheme seems
now to be, to pass the act and get up the bridge, relying, in
the case of a deficiency of money to rebuild it, that government
would be compelled, by the urgency of the occasion, to provide
the means. Such a scheme, in respect to the Post-office,
failed: but that was a singular case, an exception to the gene-
ral success of such policy. Y
The new bridge, proposed by the late Mr. Rennie, was

estimated by himtocost. . . - . «. + + £430,000
A temporary bridge 20,000

The purchase of property On the north side pt: 150,000
for approaches, Onthe southside . . - 150,000

£750,000
This sum, by reference to absolute costs, compared with
estimates of other works of the same kind, might with
propriety be taken as half the cost, even could we not
see the causes from which such an excess would arise,
viz., at ° 5 i 3 5 ; £1,500,000

* Those who have built their houses low in the Jow-lands, and feed their
cattle there, the proprietors, and others, who have allowed the foundations
of their bridges to be laid at an insufficient depth, are informed that they
came to the river, and not the river to them ; and that they ought, in choos-
ing such a neighbour, to have provided against snch an event as the pro-
posed alteration of the habits of it.

.

276 Observations on taking down and

But we have the following items* of charge, by which we
may guess that doubling the estimate will be found too small
an allowance for contingencies.

1. The bridge is to be erected in a hole where the depth of
water, at high water, is 46 feet.

2. The approaches are to be made through property of great
value, and in a thoroughfare of persons and carriages as
close as sheep in a flock,

3. On removing the old bridge.

4. On raising about 40 miles of river wall, varying from 24 to
26 inches in height, and strengthening the banks by wharf-
ing and piling, in order to provide against the effects of
frequent floods, expectant on giving a freer water-way, and
increased velocity and height, to the current.

5. On dredging out a channel for the current at low water, for
the navigation.

6. On the necessity of narrowing the river in several parts.

* Many great losses will be sustained by individuals under the heads of
these items, but for which, they will be shut out from haying any compen-
sation from the city ; nevertheless, they must be considered part of the cost
of the new bridge. It may be proper to inquire, who are to be subject to
these actions, suits, indictments, claims, and demands, which are thus
shifted from the mayor, commonalty, and citizens ? On the northern shore,
we find, among others, the Duke of Northumberland, the Rev. William
Lowth, the Duke of Devonshire, the owners of Fulham Town Meadow,
Viscount Cremorne, Lord Cadogan, Lord Grosvenor, the Chelsea Water-
works Company, the Crown, and others.

From Teddington eastward to Cotton stairs, near Westminster Bridge,
all the river walls are defective in height to resist such a flocd as that of
the 28th December, 1821, that deficiency varying from one foot at Twicken-
ham, to two feet five inches at Cotton Garden stairs ; but, generally, in the
less populous parts westward, the walls are from three to five feet below
that level ; while the lands in the populous ae northward are greatly
below it; for example, Walham-green and Chelsea are from one to five
feet below this level. The ground of the Penitentiary is eight feet be-
low this level. The Vauxhall Bridge road, and Tothill-fields, are generally
from three to four feet below this level. St. James’s Park, on the south
side, varies from sixteen inches to eight feet below this level ; and there are
various defective banks or ways, as far eastward as the Duchess of Buc-
cleugh’s, for the water to get to these parts: It will be the duty of the
commissioners of sewers forthwith to give notice to the various proprietors
to repair their banks, by raising or otherwise ; and it will be a matter de-
terminable by the custom or peculiar laws of the commissioners, whether,
in default of complying with such notices, the commissioners may direct
the proper raisings and wharfings tebe done, and rate the proprietors of
the banks for the cost, or leave them to the actions, suits, indictments, §c.,
of which the mayor and commonalty are so apprehensive. ;

After the demolition of the dam of London Bridge, this level will be that
of not a very uncommon high sea-tide, west of London Bridge.

rebuilding London Bridge. 277

7. On removing shoals and sand-banks, caused by the altera-
tion in the directions of the mid stream.

8. On the erection of starlings round the piers of the different
bridges, and especially round Vauxhall and Westminster
bridges, which do not stand upon piles. The bridges above
London bridge generally stand in shallow water, and the
foundations of them are very little below the bed of the
river, which may be undermined; for a greater depth must
be effected artificially, in the first instance, for the naviga~
tion, and subsequently, by the increased velocity of the
stream, in a manner which cannot now be guessed at *.

9. On the necessity of erecting another dam, or locks, to keep
up the water, as a substitute for the dam taken down, the
necessity for which, the locks up the river, beginning at
Teddington, prove f.

10. On the damage to shipping below the bridge, in times of
frost, by ice now stopped, at such times, by London bridge.

11. On compensations to persons possessed of wharfs, adapted
to the present state of the river above and below the bridge,
for damage to them by the alterations in the course of the
stream, and the shifting of the sand banks.

12, On compensation to persons whose trades are dependant
on the free thoroughfare over the bridge, living south and
north thereof, for seven years, during the erection, or while
it remains unfinished for want of funds to complete it.

13. On compensation to persons navigating the river, for pro-
perty destroyed, and loss of life, during the erection of the
bridge, and while it may remain unfinished for want of

* The head of water maintained 2] the lock at Teddington in winter is
one foot, in summer four feet; a similar head is maintained at Moulsey.
Dams are erected here to keep the water up the country; but the dam of
London Bridge is to be taken down to let it out.

+ The bottom of the foundations of the piers of Westminster Bridge are
five feet below the bed of the river, allowing two feet three inches, as at
Blackfriars Bridge, for grating 5 the bottom of the stone is only two feet
nine inches below the bed. e bottom of the foundations of the piers of

lackfriars Bridge is three feet nine inches below the bed, the bottom of
the stone 18 inches. How much below the bed of the river are the founda-
tions of Vauxhall, Waterloo, and Southwark Bridger ? The bottom of the
—— piers of Waterloo Bridge are only 15 feet below the springing of the
arches.

278 On rebuilding London Bridge.

money to complete it, which, at a moderate estimate, may
be taken to exceed the same loss arising from the old
bridge in the last twenty years.

Hence, in any view of the question, it would be unreasonable
to consider the cost of this bridge at less than one million and
a half.

These observations may probably, through your Journal,
cause more inquiry to be made into this important question,
than the impatient determination, at any rate to have a new
bridge, has hitherto allowed. They may make the failure of
the proof of the expediency of removing the dam of the bridge
manifest ; also shew the deficiency of the means for building
the bridge, without taxes to a large amount being eventually
levied on the public ; and remove the general delusion, that the
thoroughfare over the bridge will be more free than it is at pre-
sent. They may cause some reflections on the forbearance of
the government regarding the public dignity, but scrupulous of
increasing the public expenditure, in listening for a moment to
such an useless and dangerous expense, which, directly or in-
directly, will cause taxes to be raised to pay a million at least,
WHILE THE WANT OF A PALACE IS A GENERAL REPROACH
TO THE NATION, AND A SUBJECT FOR DERISION ‘WITH
EVERY FOREIGNER.

Arr. VII. Estimate of the Force of Explosion of Coal
Gas; laid before the Committee of the Royal Society
in the Year 1814.

[By one of its Members. }

Ir must be confessed, that without direct experiments on the
force of any exploding compound, we can obtain nothing more
than probability by calculating from the analogy of other simi-
lar effects: but provided that we take sufficient care not to
underrate the forces in question, we may obtain, from such a

comparison, at least a useful estimate of their greatest possible
magnitude. ;

Estimate of the Force of Explosion of Coal Gas. 279

Dr. Henry has found (Phil. Trans. 1808), that good coal gas
requires for its combustion, about twice its bulk of oxygen gas,
and affords a little more than its bulk of carbonic acid. Now
since common air contains only 21 per cent. of oxygen, it can
combine with no more than 12 per cent. of coal gas; so that
112 parts of the mixture contain but 33 of substances capable
of affording heat, while the remainder tends, in some measure,
to impede their union. Hence we cannot suppose the heat,
thus generated, to exceed about 1 of the heat which would be
excited in a mixture of the gas with pure oxygen. And we
shall probably exceed the truth, in allowing to the combustion
of such a mixture, a heat equal to that which is evolved in the
deflagration of gunpowder; which is sufficient, upon the most
probable estimate, to increase in the ratio of 1 to 80, the natu-
ral elasticity of the fluids generated, which amount to 250 times
the bulk of the powder, so that the elasticity, thus augmented,
becomes equal to 20,000 atmospheres. It is true, that some of
the solid substances contained in gunpowder may possibly be
converted into vapour, and may contribute to its effect: but
we have no sufficient reason to believe that the vapours of any
of these substances would be more elastic than air; and Count
Rumford’s hypothesis, concerning the effect of steam, is every
way inadmissible; since even if nitre contained water of cry-
stallization, its vapour would be little more effectual than an
equal weight of the gaseous substances.

We may, therefore, suppose the exploding mixture to acquire
a degree of heat, capable of increasing its elasticity in the ratio
of 1 to 20. Dr. Ingenhousz, following Robins, makes the ex-
plosive force of a mixture of oxygen and hydrogen equal to 4
atmospheres only: but the assumption of a degree of heat equal
only to that, which Robins obtained in a fire, is wholly arbitrary :
and a single drop of ether, in a bottle of oxygen, appears to
have exploded with a force much more than commensurate to
such a cause. On the other hand, when we consider with what
safety a mixture of oxygen and hydrogen may be made to ex-
plode in a common quart bottle of green glass, we cannot hesi-
tate to allow that 80 atmospheres must be a very ample estimate

280. Estimate of the Force of

of the force of explosion of a mixture of oxygen and coal gas.
As the ignited gas expands, it loses a portion of its elasticity,
not only by the diminution of its density, but also by the effect
of the expansion on its temperature, which may be estimated
as altering the elasticity in the proportion of the biquadrate
root of that of the densities.

Calculating upon these grounds, we find that the whole me-
chanical power of an explosion of 15,000 cubic feet of a mix-
ture of coal gas, and common air, is equal to that of the explo-
sion of 6 cubic feet, or 4 barrels, of gunpowder ; and if we sup-
pose the heated gases in both cases to escape, and mix with the
common air in a building containing 30,000 cubic feet, so as to
produce an effect commensurate to the temperature of the whole
mixture, the explosion of about 15 cubic feet, or 10 barrels of
gunpowder, would be required, in order to produce, like the gas,
a force of about 10 atmospheres for the whole space. It must,
however, be recollected, that gunpowder, thus disposed, is very
unfavourably situated for producing violent effects; and that a
much smaller quantity, in ordinary cases, would be more for-
midable than the explosion of the coal gas.

A more precise idea of the effects of such an explosion may
be obtained from the calculation of its projectile effects, which
would carry some parts of the wall of the surrounding building
to a height of nearly 150 yards, and others to a distance
of nearly 300. If the walls were in immediate contact
with the gasometer, the height and distance would be about
twice as great. But a roof of carpentry and tiles being lighter,
would be carried higher, while the lateral force of the explo-
sion would be diminished.

Supposing the explosion of the gas to be unconfined, the
shock would throw down a brick wall, 9 feet high, and 18 inches
thick, at the distance of about 50 feet from the centre; it would
probably break glass windows at 150 yards, and at 300, would
produce an effect similar to the instantaneous impulse of a very
high wind.

CALCULATION.
In order to compare the whole forces of expansion in a con-

Explosion of Coal Gas. 281

fined channel, let the length occupied initially by the gas be
a : then, when it becomes az, the elasticity will be diminished
in the ratio of 1 to 23; and the force will be expressed by
nat — ], and the fluxion of half the square of the velocity by
Py se ME and the fluent will beAnax* — ax, which is
initially = — 4na — a, and finally, when a — 1=0,and

nis né, and 2 = xt, = — 4ax — ax; and the difference
showing half the square of the velocity generated, is (4n + 1

= 5n®) a. When n = 20, the expression becomes 26a;
when x = 20 000, 66 204a; and in order to make these values

of the former; and

equal, the latter value of a must be :
2540

15000
2540

In a similar manner, when a is the radius of a sphere, or of

a hemisphere, which expands in every direction, the elasticity

= 5,9;

=r r ‘ rae
will vary as x 4, and the fluxion will be naz “4 4 —a x, and

11 ‘ : :
the fluent — i nax 4 — ax; which, being corrected, gives

4 15 4
for the half square aes - a ni> ja,

The fluent, thus found, may be compared with the feet in
which the force of gravity would produce an equal velocity, by
increasing it in the ratio of the pressure of an atmosphere to the
weight to be moved: that is, for a brick wall 18 inches thick,
multiplying it by 11: so that, when x = 20, and a = 15,
.5242a = 865 feet, the height of ascent: or, supposing the space
doubled, and = 10, and a about 184, the height would be
430 feet.

Where the explosion of the gas takes place without an ob-

nit atmospheres, the

stacle, the mean force being about

velocity of expansion will be about 2000 feet in a second; or,
perhaps, a little greater, on account of the lightness of the gas;

282 Estimate of the Force of Explosion of Coal Gas.

but this excess will be compensated, when the velocity is after-
wards communicated to the surrounding atmosphere. With
this velocity, the centre of inertia of each elementary pyramid
ofthe sphere will advance from the distance 3 x 15 to 3 x 33.35 feet,
through 133 feet, in -1, of a second: and at any greater dis-
tance d, the velocity of the impulse will be reduced from 2000

to 2000 x . qe oaete

, its duration being always =1, of a

second. Thus the velocity of a very high wind being 60 feet in
a second, the impulse would retain this force at the distance of
833 feet: and in order to determine at what distance it would
overset a wall 9 feet high, and 13 thick, we must first find the
height through which the centre of oscillation of the wall, at $
of its height, must ascend, in order to be immediately over the

point of support, that is / (36 +1) —6= ote foot: and

the velocity corresponding to this height would be generated
by the force of gravity in ole a = aa of a second : and

in order to be generated in =1,, it requires a force 10.43 times
as great, or equal to the pressure of a column of brick 15.64
feet high; that is, 15.64 x 125 = 1955 pounds for every square
foot; which is equivalent to the pressure occasioned by a velocity
of 966 feet in a second, and answers to a distance of 52 feet.

Arr. VIII. On the Crystalline Forms of Artificial Salts.
By Mr. Levy. Communicated by the Author.

Tue relation between the chemical composition of a sub-
stance, and its crystalline form, has not yet been ascertained ;
and it is only from a comparative examination of the exact
analyses and forms of a great many simple and compound
bodies, that it may be expected to be deduced. The data
furnished by Mineralogy are not sufficient to discover it; be-
cause not. only there are too few simple compounds found
crystallized, but also because those which are met. with have

Mr. Levy on the Forms of Artificial Salts. 283

not a sufficient chemical analogy. On the contrary, the com-
position of the substances crystallized artificially is better
known than that of minerals, or at least more easily ascer-
tained; and, perhaps, a sufficient number among them, having
a certain desired relation of composition, may be examined,
to lead to some important result. It is in this point of view
that the determination of their forms appears to me to deserve
attention.

This subject has acquired, lately, a new degree of interest,
from the two papers of Mr. Mitscherlich. He has himself
examined a great many artificial crystals, and has given, in
the last of his two papers, it seems, with great accuracy, the
forms and complete determination of many salts produced by
the combination of the phosphoric and arsenic acid with several
bases. His object is to establish, that the same number of
atoms, combined in the same manner, produce the same crys-
talline form ; and that the same crystalline form is independent
of the chemical nature of the atoms, and is only determined by
their number and relative position. In both his papers, and
especially in the last, will be found the facts and reasons he
adduces in support of this opinion; and, I think, that after
their perusal, even those who are most adverse to generaliza-
tion, must, at least, admit that the analogies and identities of
forms, which he has noticed in several compounds, are ex-
tremely interesting. Another proposition he advances is, that
the same substance may crystallize under two different and
incompatible forms ; and mentions, as examples, carbonate of
lime and arragonite, and the two forms he has obtained for the
bi-phosphate of soda*.

The preceding considerations, and the results obtained by
Mr. Mitscherlich, made me very desirous to begin an examina-
tion of artificial crystals ; and having mentioned my intention to
Mr. Children, he very kindly offered to take his share of the

.* There is not, however, the same degree of incompatibility between the
two forms of the bi-phosphate of soda, as between those of arragonite and
carbonite of lime, the one being a right rhombic prism, and the other a rec-
tangular octahedron ; but] suppose, Mr. M. has satisfied himself that the
one could not simply be deduced from the other, h ’

284 Mr. Levy on the

work, by preparing the crystals, upon the purity of which I
could therefore depend. ‘At his recommendation, Mr. Brande
has also allowed me to select some crystals from those in his
collection, preserved in the laboratory of the Royal Institution,
and at Apothecaries’ Hall.

With this help, I propose to employ some leisure hours to
the determination of as many crystallized substances as I shall
be able to procure. This paper, and some subsequent ones,
will contain the result of my researches. Besides the primi-
tive, I shall give one or two of the forms which most com-
monly occur. I measure the angles with a goniometer belong-
ing to Mr. Lowry, and which is divided to half a minute; and
I besides use the principle of the repetition of angles, in order
to obtain a greater accuracy. At the suggestion of Dr. Wol-
laston, I call the solid, from which the secondary forms are
supposed to be derived, by the appellation of primitive, when
obtained by cleavage; and by that of primary, in the contrary
case. I designate the angles and edges of the primitive, by
the same letters as Haiiy; and the secondary planes, by the
signs of the decrements from which they are supposed to result.

I have begun with the salts of potash.

Nitrate of Potash.

q pow g
Incidences.
mon m)!. Li. NO. S109 50°
DE eit abieve lala ty enkey aie 135.36
TUR A Sia ee” |e 160 42
COMO ie, ‘stows aa. ihe 120 (25

Primitive form.—A right rhombic prism, the incidence of
the two lateral planes of which is 109° 50’, and the ratio be-
tween one side of the base and the height nearly that of
1 to 0,48.

Crystaltine Forms of Artificial Salts. 285

Cleavage.—Parallel to all the faces of the primitive, and
also to a plane passing through the two short diagonals of the
bases.

Sulphate of Potash.

Incidences.
4 monm . . . 120° 30 aon? Sao 15. |) S0% OF
b'onm ... . 146 22 Dee ean ght Lad giao
Bra wauits, ies 120 206 Lie) Sek PRR *E SR 143 A
Pes cele ay) 8) hs 119 45 CME er te tne Te) na
SBGt Te Wt ¥ 150 e240, OBR, SAN 143 (17

rt ge gietn atx OU yoko

Primitive form.—Right rhombic prism, the incidence of the
two lateral planes of which is 120° 30’, and the ratio between
one edge of the base and the height, nearly that of 10 to 13.

Cleavage.—Parallel to all the faces of the primitive form,
and also to planes passing through both the diagonals of the
bases.

In many of the small crystals, the faces P, b1, 5%, ht, do not
occur.

Hyposulphate of Potash.

monm . . . 120° m on P ike OSs Or
BU en aera a 159 G2). JOY) SRO Ze
: 6. we SF 50!

286 ‘ ~ Mr. Levy on the ©

Primitive form.—A regular six-sided prism, in which one
side of the base is to the lateral edge in the ratio of 1 to 0,37.
Cleavage.—Parallel to all the faces of the primitive form.

Bi-carbonate of Potash.

103° 41’
126 51

Primitive form.—A right oblique-angled prism of 103° 41’,
in which the three edges 6, c, h are nearly in the ratio of the
number 1, 2,03 and 0,762.

Cleavage.—Parallel to the lateral planes of the primitive,
and also to a plane passing through the two edges g.

Chlorate of Potash.

Primitive form.—An oblique rhombic prism, the lateral
planes of which are inclined at an angle of 103° 55’; and the
base, upon each of the ‘lateral planes, of 105° 34’. The lateral
edge is very nearly equal to one side of the base.

Cleavage.—Parallel to all the faces of the primitive form.

Crystalline Forms of Artificial Salts. 287

Most of the crystals I have observed were macles as repre-
sented in the third figure.

Sub-chromate of Potash.

Incidences.
mon m Ose toe ae 107° 8’
Whe asl eae ual an tose, OO
CAO vey vertse Ad. We.) ie beet ACOSO

byonm . sf 4, Je, SOOO

the ratio of one side of the base, to the lateral edge of the
prism, is nearly that of 5 to 2.

Cleavage.— None very distinct.

This is the yellow chromate of potash, which, from the re-
marks of Mr. Taffaert, in the Annales de Chimie for 1823, ap-
pears to be a sub-chromate.

Bi-chromate of Potash.

Incidences.
on m on P on t
P Site an SECMLAT T. Sct sash OO™ lions, Sie e Jaro iant
Miele asian “th abi eeisgititnss|, gH AG: . 96
PE PT eres |r: ais, Asaile MOL 36 i
Bijele le MAI Gti: Hil. 186 v{Sthinsinent 85144
lie ole erg UNA) 38s nn ‘ei ADEIMIG Som ie, 5-149 \ SF,

wits. $s Ais | Saluda Omiereas
Primitive form. A doubly oblique prism, in which the in-
cidences of the base p, on the two lateral planes m, ¢, are, re-
Vou. XV. . U

288 Mr. Levy on the Forms of Artificial Salts.

spectively, 98° 14’, and 91° 36’; and that of m on #, 96°; the
lengths of the three edges, f, d, h, meeting in the point o, are
nearly in the ratio of the numbers 1., 0.55, 1.125.

Cleavage.—Very easily obtained, parallelly to all the planes
of the primitive.

Prussiate of Potash.

Primary form.—Octahedron, with a square base, in which
the incidence of two adjacent faces of the upper pyramid
is 98° 11’,

Cleavage.—Easy, in a direction perpendicular to the axis of
the octahedron.

[To be continued. ]

Art. IX. Historical Statement respecting Electro-Mag-
netic Rotation. By M. Farapay, Chem. Assist. in
the Royal Institution.

In the XIIth Volume of this Journal, at page 74, I published
a paper on some new electro-magnetical motions, and on the
theory of magnetism. In consequence of some discussion,
which arose immediately on the publication of that paper, and
also again within the last two months, I think it right, both in
justice to Dr. Wollaston and myself, to make the following
statement :-—

Faraday on Electro-Magnetic Rotation. 289

Dr. Wollaston was, I believe, the person who first enter-
tained the possibility of electro-magnetic rotation; and if I now
understand aright, had that opinion very early after repeating
Professor Oersted’s experiments. It may have been about
August 1820, that Dr. Wollaston first conceived the possibility
of making a wire in the voltaic circuit revolve on its own axis.
There are circumstances which lead me to believe that I did
not hear of this idea till November following ; and it was at the
beginning of the following year that Dr. Wollaston, provided
with an apparatus he had had made for the purpose, came to the
Institution with Sir Humphry Davy, to make an experiment of
this kind. Iwas not present at the experiment, nor did I see
the apparatus, but I came in afterwards, and assisted in making
some further experiments on the rolling of wires on edges’.
I heard Dr. Wollaston’s conversation at the time, and his
expectation of making a wire revolve on its own axis; and I
suggested (hastily and uselessly) as a delicate method of sus-
pension, the hanging the needle from a magnet. I am not
able to recollect, nor can I excite the memory of others to the
recollection of the time when this took place. I believe it was
in the beginning of 1821.

The paper which I first published was written, and the expe-
riments all made, in the beginning of September, 1821. It
was published on the Ist of October; asecond paper was pub-
lished in the same volume on the last day of the same year. I
have been asked, why in those papers I made no reference to
Dr. Wollaston’s opinions and intentions, inasmuch as I always
acknowledged the relation between them and my own expe-
riments? To this I answer, that upon obtaining the results
described in the first paper, and which I shewed very readily to
all my friends, I went to Dr. Wollaston’s house to communicate
them also to him, and to ask permission to refer to his views
and experiments. Dr. Wollaston was not in town, nor did:he
return whilst I remained in town; and, as I did not think I
had any right to refer to views not published, and as far as I

* See Sir Humphry Davy’s Letter to Dr.Wollaston. Phil. Trans, 1821. p. 17.
U2 }

290 Faraday on Electro-Magnetic Rotation.

knew not pursued, my paper was printed and appeared without
that reference whilst I remained in the country. I have
regretted ever since I did not delay the publication, that I
might have shewn it first to Dr. Wollaston.

Pursuing the subject, I obtained some other results which
seemed to me worthy of being known. Previous to their ar-
rangement in the form in which they appear at page 416 of
the same volume, I waited on Dr. Wollaston, who was so kind
as to honour me with his presence two or three times, and
witness the results. My object was then to ask him per-
mission to refer to his views and experiments in the paper
which I should immediately publish, in correction of the error
of judgment of not having done so before. The impression
that has remained on my mind ever since, (one-and-twenty
months,) and which I have constantly expressed to every one
when talking of the subject, is, that he wished me not to do so.
Dr. Wollaston has lately told me that he cannot recollect the
words he used at the time: that, as regarded himself, his feelings
were it should not be done, as regarded me, that it should; but
that he did not tell me so. I can only say that my memory
at this time holds most tenaciously the following words: “I
would rather you should not ;” but I must, of course, have been
mistaken. However, that is the only cause why the above. state-
ment was not made in December 1821; and that cause being re-
moved, I am glad to make it at this, the first opportunity.

It has been said I took my views from Dr. Wollaston. That
I deny; and refer to the following statement, as offering some
proof on that point. It has, also, been said, that I could
never, unprepared, have gained, in the course of eight or ten
days, the facts described in my first paper. The following
information may elucidate that point also:

It cannot but be well known, (for Sir Humphry Davy him-
self has done me the honour to mention it,) that I assisted him
in the important series of experiments he made on this subject.
What is more important to me in the present case, however, is
not known; namely, that I am the author of the Historical
Sketch of Electro-Magnetism, which appeared in the Annals of

Faraday on Electro-Magnetic Rotation. 291

Philosophy, N.S. vols. If. and III. | Nearly the whole of that
sketch was written in the months of July, August, and Sep-
tember, of 1821; and the first parts, to which I shall particu-
larly refer, were published in September and October of the
same year. Although very imperfect, I endeavoured, as I think
appears on the face of the papers, as far asin me lay, to
make them give an accurate account of the state of that branch
of science. I referred, with great labour and fatigue, to the dif-
ferent journals in which papers by various philosophers had
appeared, and repeated almost all the experiments described.

Now this sketch was written and published after I had heard
of Dr. Wollaston’s expectations, and assisted at the experiments
before referred to; and I may, therefore, refer to it as a public
testimony of the state of my knowledge on the subject before |
began my own experiments. I think any one, who reads it
attentively, will find, in every page of the first part of it, proofs
of my ignorance of Dr. Wollaston’s views; but I will refer
more particularly to the paragraph which connects the 198th
and 199th pages, and especially to the 18th and 19th lines of
it; and also to Fig. IV. of the accompanying plate. There is
there an effect described in the most earnest and decided
manner, (see the next paragraph but one to that referred to,) my
accuracy, and even my ability, is pledged upon it; ana yet
Dr. Wollaston’s views and reasonings, which it is said I knew,
are founded, and were, from the first, as | now understand, upon
the knowledge of an effect quite the reverse of that I have stated.
I describe a neutral position when the needle is opposite to the
wire; Dr. Wollaston had observed, from the first, that there was
no such thing as a neutral position, but that the needle passed
by the wire: I, throughout the sketch, describe attractive and
repulsive powers on each side the wire; but what I thought
to be attraction to, and repulsion from the wire in August, 1821,
Dr. Wollaston long before perceived to arise from a power not
directed to or from the wire, but acting circumferentially round
it as axis, and upon that knowledge founded his expectation.

I have before said, I repeated most of the experiments de-
scribed in the papers referred to in the sketch; and it was in

292 Faraday on Electro-Magnetic Rotation.

consequence of repeating and examining this particular experi-
ment, that I was led into the investigation given in my first
paper. He who will read that part of the sketch, above referred
to *, and then the first, second, and third pages of my papert,
will, I think, at once see the connexion between them; and from
my difference of expression in the two, with regard to the at-
tractive and repulsive powers, which I at first supposed to exist,
will be able to judge of the new information which I had, at the
period of writing the latter paper, then, for the first time
acquired.

Arr. X. Proceedings of the Royal Society.

The following papers have been read at the table of the Royal '
Society since our last report:

March 6. Ona new phenomenon of electro-magnetism, by Sir Hum-
phry Davy, Bart., P.R.S.

i On fluid chlorine, by Mr. Faraday, communicated by the Pre-
sident.

20. On the motions of the eye in illustration of the muscles and
nerves of the orbit, by Charles Bell, Esq., communicated by the Pre-
sident.

April 10. An account of an apparatus, on a peculiar construction,
for performing electro-magnetic experiments, by Wm. H. Pepys, Esq.

On the condensation of several gases into liquids, by Mr. Faraday,
chemical assistant, Royal Institution, communicated by the President.

17. On the application of liquids formed by condensation of gases,
as mechanical agents, by Sir Humphry Davy, Bart., P.R.S.

On the temperature of the Sea at considerable depths, by Captain
Sabine.

24. Details of experiments made with an invariable pendulum in
various paces on the South American station, by Captain Basil
all, R.N.

May 1. On the changes of volume produced in gases in different
states of density by heat, by Sir Humphry Davy, Bart., P.R.S.

His Grace the Duke of Northumberland was elected a Fellow of the
Society.

§. Continuation of Professor Buckland’s account of the caverns con-
taining bones in England and Germany.
William, Earl of Dartmouth, was admitted a fellow of the society.

* Annals of Philosophy, N.S., ii. 198,199. + Quarterly Journal, xii. 7i—76.

Proceedings of the Royal Society. 293

15. Further remarks on the evidence of diluvial action in the caves of
Germany, by Professor Buckland.
At this meeting Mr. William Clift was elected into the society.

29. Description of a magnetic balance, with an account of some
recent experiments on magnetic attraction, by Mr. W.S. Harris, com-
municated by the President.

At this meeting of the society the following gentlemen were elected
fellows: viz., Peter Barlow, Esq., Arthur de Capel Brooke, Esq.,
J.S. Harford, Esq., the Rev. Lewis Evans, Samuel Reynolds Solly,
Esq., and the Rev. J. M. Traherne.

June 5, A case of pneumato-thorax, with experiments on the absorp-
tion of different kinds of air introduced into the pleura, by John
Davy, M.D.

On fossil-shells, in a letter to the President, by L. W. Dillwyn, Esq.

John Rennie, Esq. was elected a fellow of the society.

12. On the existence of bitumen in certain minerals, by the Rt. Hon.
George Knox, F.R.S.

On the diurnal variation of the horizontal magnetic and dipping
needle, by P. Barlow, Esq.

19. On the diurnal deviations of the horizontal needle, when under
the influence of magnets, by J. H. Christie, Esq.

Astronomical observations made at Paramatta, communicated by
Sir T. Brisbane.

Contributions towards the history of the cocoa-nut tree, by H. Mar-
shall, Esq.

An account of the effect of mercurial vapours on the crew of H. M.
ship Triumph, in the year 1810, by W. Burnett, M.D.

On the apparent magnetism of metallic titanium, by W. H. Wollas-
ton, M.D., V.P.R.S.

Tables relating to certain deviations which appear to have taken place
in the north polar distance of some of the principal fixed stars, by
J. Pond, Esq., F.R.S,. Astronomer Royal.

Account of a case of pneumato-thorax, in which the operation of
tapping the chest was performed, with some observations on the power
of mucous membranes to absorb air, by John Davy, M.D., F.R.S.

Account of experiments made with an invariable pendulum at New
South Wales, by Major-General Sir Thomas Brisbane, K.C.B., F.R.S.,
communicated by Captain Henry Kater, F.R.S., in a letter to the
President.

Second part of the paper on the nerves of the orbit, by C.Bell, Esq.

On astronomical refractions, by J. Ivory, A.M., F.R.S.

On algebraic transformation, as deducible from first principles, and

onnected with continuous approximation, and the theory of finite and
Aluxional differences, including some new modes of numerical solution,
by W. G. Horner, Esq.

Major-General Sir George Murray was elected fellow of the society.

The Society then adjourned over their long vocation, to meet
again on Thursday, November 20.

294

Art. XI, PROGRESS OF FOREIGN SCIENCE.

1. On the Cold produced by the Evaporation of Liquids. By
M. Gay-Lussac.

This memoir was read to the Academy of Sciences so long
ago as 1815, but its publication was deferred, in the view of
rendering it more complete ; an intention which its author has
not possessed leisure to realize.

The evaporation of a liquid may take place in a vacuum or ina
gas. The depression of temperature, which results, differs in these
two circumstances. In a vacuum, supposing the vapour to be
absorbed as soon as it is produced, the greatest cold takes place
for a determinate temperature of the ambient medium, when the
caloric absorbed for the transformation of the liquid into vapour
is equal to that entering the liquid from the sides of the re-
ceiver*. Forit is evident that, since the latter augments with
the difference of temperature between the liquid and the sur-
rounding medium; and as, on the contrary, the elastic force of
the vapour goes on continually to diminish, as well as its velo-
city, (of formation,) there must necessarily be a period, at which
the caloric absorbed by the vapour shall be equal to the caloric
poured in by the surrounding walls. But if we lower the tem-
perature of the ambient medium, the limit of the cold will re-
trocede, and it may do so, even indefinitely, whilst the vapour
of the liquid shall preserve an appreciable tension. Thus M.
Gay-Lussac has frozen mercury with ease, by surrounding with
a frigorific mixture of ice and salt, the vessels in which the
aqueous vapour was produced and absorbed by the apparatus
of professor Leslie ; and he does not doubt, that, with analogous
means, and very evaporable liquids, we may arrive at a degree
of cold much more considerable than by the mixtures.

Suppose, now, that the evaporation takes place in a gas, per-
fectly dry, of a determinate temperature. Here new causes
come to influence the production of the phenomenon, which it is
necessary to appreciate.

In the first place, the evaporation is retarded by the gas,
which presses on the liquid. It would amount to nothing, in a
gas perfectly at rest, whose density, under the same pressure,
would be equal to that of the vapour; and the temperature
being supposed constant, it would augment nearly in proportion
to the velocity of the gas, until this velocity was equal to that
which the vapour would assume iz vacuo. The cold produced
by the vapour, depends on it, up to a certain point; for if it
were very little, it would be possible, that the heating produced

* Itis here supposed, that the evaporation takes place over the whole
surface of the liquid, as with a thermometer with a moistened bulb. This
is the most favourable case for obtaining the maximwn of cold.

Gay-Lussac on the Evaporation of Liquids. 295

by the surrounding bodies, would be more rapid than the cool-
ing due to the evaporation; and thus, the cold could not reach
its limit.

In the second place, the liquid, evaporating only by means of
the air, which impels against its surface, cannot evidently cool
as much as in vacuo; and for a given initial temperature, the
cold produced is at its maximum, when the caloric, absorbed by
the vapour, is equal to that which the air loses, to put itself in
an equilibrium of temperature and pressure with it, plus the
caloric poured into the evaporating surface by the surrounding
bodies ; but the quantity of the latter, when the cold produced
is only a few degrees, is small in comparison of the other, and
may be neglected. From the latent heat of the vapour of the
evaporable liquid, the law of its elastic force relative to the tem-
perature and its density, on one hand ; and, on the other, the
capacity of the air for heat, its temperature, its density, and its
pressure, M. Gay-Lussac has constructed a formula, for calcu-
lating the degree of cold, which should be produced by evapo-
ration. In order to compare his theory with experiment, he
determined directly the depression of temperature produced by
a current of dry air on a mercurial thermometer, surrounded with
moistened cambric. The air issuing from a gasometer, under a
constant pressure, passed first through a tube filled with chloride
of calcium; from this tube it entered another, where it meta
thermometer destined to show its temperature ; then five cen-
timetres further on, (two inches E.,) another thermometer with a
moistened surface, which it enveloped on every side. Thence, it
diffused itself freely in the atmosphere, without suffering fur-
ther change of pressure. The calculated and experimental
results coincide very nearly. We shall content ourselves with
giving the latter.

Temperature of the Depression of temperature pro-

dry air at the pres- duced by evaporation below
sure of 29.9 inches. the temp. of the air.

OFC: 5.82°, C,
1 6.09
2 6.37
3 6 66
4 6.96
5 7.27
6 7.59
7 7.92
8 8.26
9 8.61
10 8.97
11 9.37
12 9.70
13 10.07

296 Progress of Foreign Scrence.

Temperature of the Depression of temperature pro-
dry air at the pres- duced by evaporation below
sure of 29.9 inches. the temp. of the air.

14° C. 10.44° C,
15 ‘ 10.82
16 . 11.20
17 11.58
18 11.96
19 12.34
20 12.73
21 13.12
22 13.51
23 13.90
24 14.30
25 14.70

The heat given up by the air, during evaporation, depending
evidently on its density, it follows, that, all other things being
equal, the cold produced ought to increase as the density
diminishes. We have hitherto supposed that the air was per-
fectly dried; but, if we take it in the ordinary hygrometric state,
the cold produced by evaporation will not be so considerable,
and it will be even null, where the air is saturated with humidity.
The cold is relative to the quantity of water which the air can
suffer to pass into the state of vapour; but this quantity is not
immediately known, by that already contained in the air, before
it arrives at the moist surface. Suppose, in fact, that the tem-
perature of the air is 10° C., and that it is half saturated with
humidity ; suppose, further, that the cold produced amounts to
4°, it is evident that, at this term, the air which was half satu-
rated with moisture at 10°, will be more highly so on account
of the cooling which it has experienced, and that the quantity
of water which can evaporate, is precisely equal to what the air
wants at the temperature of 10°—4°=6°, in order to be sa-
turated.

‘‘In general, we may succeed in knowing the hygrometric
state of the air, according to the cold produced by evaporation ;
but as this cold is variable with the pressure of the air, its
temperature, its degree of humidity, we would require very ex-
tensive tables to determine it with exactness. 1 was willing
to undertake this labour, repeating my experiments on the cold
produced by evaporation, and making new ones; but I have
been disheartened by its length, as wellas the want of sufficient
data, and especially by the consideration that the ingenious
process of Leroi was susceptible of a more easy application, and
that in the actual state of physics, it was much preferable.”
We heartily concur in this preference of M. Gay-Lussac, which
brings a strong additional argument in favour of Mr. Daniell’s
hygrometer, founded on the principle of Leroi, and against Mr.

M. Serullas, on Hydriodide of Carbon. 297

Leslie’s, constructed on the other plan.—Amnn. de Chimie et de
Physique, xxi. 82.
2. Memoir on the Density of Vapours, by M. Cés. Despretz.

Although we can find no new facts in this paper, it deserves
notice from the mode of investigation. The process followed
for comparing the weights of gases, has never been applied to
vapours, because it was foreseen, that, on taking the densities
at the boiling points of the liquids, the contact of the cool sides
of the balloon would cause a portion of vapour to be liquefied.
It would not be so,if the experiments were made at the tempera-
ture of the surrounding bodies. We might then weigh vapours
as we weigh gases. M. Despretz conceives himself to be the
first person who has done this. We obtain, adds he, vapour
perfectly pure, and at the actual temperature of the surrounding
bodies, by fixing a stop-cock to a barometric tube, whose in-
ternal diameter is triple that of the ordinary tubes, and by
introducing into this tube the liquid whose vapour we wish to
weigh. We adapta balloon to it, well exhausted of air; this
is soon filled with vapour; an ordinary barometer is plunged
into the same bath, so that we know the elastic force of the
vapour weighed, by the difference of height of the mercury in
the two tubes. Lastly, we judge if the elastic force is at the
maximum, and consequently, if the space be saturated, by the
inspection of a third barometer-tube. In this third tube, there
is liquid in excess, which will not be the case with the tube
which furnishes vapour to the balloon, except in so far as the
mercury in it is at the same height as in the first.

We consider the suggestion of M. Despretz ingenious, but
the details are obscure. A plate of his apparatus should haye
been given in the Annales.—Ann. de Ch. et de Ph. xxi. 143,

3. On the Hydriodide of Carbon (hydriodure ;) a new Mode of
obtaining zt. By M. Serullas.

The preparation of the hydriodide of carbon, by the action
of potassium on alcohol holding iodine in solution, being prac-
ticable by few persons, from the price of potassium, M. Serullas
sought to obtain this new body by other and easier means.
After different attempts, all founded on the re-action of bodies
which could present nascent olefiant gas to iodine, M. S.
has succeeded in readily procuring hydriodide of carbon. On
chloride of iodine, made by saturating pulverulent iodine with
chlorine in a globe, he poured from five to six times its weight
of alcohol, at 34°, (about 0.847 sp. gr.) The liquid, at first
turbid, became clear in a few instants with deposition of some
saline matters proceeding from the impurity of the iodine, as
also of a small quantity of an acid iodate having potash for its
base, which likewise existed in the iodine.

This alcoholic solution of chloride of iodine being treated

298 Progress of Foreign Science.

with small portions of an alcoholic solution of caustic potash,
there was instantly formed a very abundant yellowish, curdy
precipitate, composed of a mixture of hydrochlorate and acid
iodate of potash. The acid iodate, it ought to be observed,
exists only at the commencement. . The saturation being con-
tinued and pushed to a slight alkaline excess, the liquid, which
was strongly coloured at a certain period of the saturation,
by the separation of the iodine of the sub-chloride, appeared
after some moments of repose above the saline deposit;
of a lemon-yellow colour, having the saccharine taste given to
it by the hydriodide of carbon, which it holds in solution, along
with the hydriodate of potash. We decant and wash the salts
several times with alcohol, to carry off the whole of the
hydriodide ; which is indicated by the alcohol ceasing to be
coloured. The salts are set to drain on a filter, and the liquid
is united to the other portions, after filtration. We evaporate
the liquid at a gentle heat; the hydriodide crystallizes; and
we separate it before the entire evaporation of the liquid, by
throwing it on a filter and washing it with cold water, till this
be no longer affected by nitrate of silver; a proof that the
hydriodide is freed from the hydriodate of potash which it
might have retained. We separate afterwards, by solution and
crystallization, the hydrochlorate from the iodate, which we
make use of, converting it into an iodide by fusion.

M. Serullas afterwards contrived the following modification
of the process: Into alcohol of the above strength, mixed with
much more iodine than it could dissolve, he passed a current
of chlorine, which made the colour of the iodine speedily dis-
appear, whose solution was meanwhile aided by agitation with
a glass tube. The stream of gas having been continued some
instants after the disappearance of the iodine, the yellowish
liquor, considered to be then an alcoholic solution of chloride
and sub-chloride of iodine, was saturated in the same way as
the other, by an alcoholic solution of caustic potash, which
immediately determined the formation of the same yellow curdy
precipitate containing the same substances: iodate, hydro-
chlorate of’potash, and hydriodide of carbon in solution; the
last in as large a proportion as by the process of mingling
alcohol with the chloride of iodine separately prepared. The
acid-iodate of potash, which instantly falls down, from its inso-
lubility in alcohol, has, like iodie acid, a sharp and astringent,
but less intense taste than that of iodic acid. Its solution
merely reddens, without destroying, tincture of litmus. This
salt is less soluble than the neutral iodate of the same base ;
and its crystals, when slowly formed, present truncated pyra-
mids, whose base is a rectangular parallelogram, or small
prisms, with four very transparent faces, terminated by
pyramid of four faces.

M. Serullas, on Hydriodide of Carbon. 299

_M. Serullas conceives that, without the concurrence of potash,

the simple act of dissolving chloride of iodine in alcohol, is
not sufficient to decompose the water, and produce hydriodide
of carbon ;: for the existence of this hydriodide is not manifested
till during the saturation, beginning, probably, at the moment
when the iodine of the sub-chloride is set at liberty, and it is
only when the saturation is completed, that the liquor acquires
the yellow colour, the saccharine taste, and the peculiar odour,
which distinguish the hydriodide. Saturation by pure mag-
nesia produces no hydriodide. This compound is solid, of a
lemon-colour, and a saccharine taste, which becomes very mani-
fest when it is dissolved in alcohol. It crystallizes in spangles of
a brilliant aspect. Its smell is aromatic, approaching nearly
to that of saffron. Its specific gravity is nearly double that
of water. Itis not sensibly soluble in this liquid. It dissolves
in 80 times its weight of alcohol of 0.825 sp. grav., at the
ordinary temperature; and in 25 times, at a temperature of
95° Fahr. Seven parts of ether dissolve one of hydriodide.

Fat and volatile oils dissolve it readily. In the latter, at
least in the essence of lemons, it suffers an alteration; for,
on exposure to light, charcoal is evolved, and the iodine be-
comes free. Sulphuric, sulphurous, nitric, and muriatic acids
have no action upon it; nor has a solution of chlorine in
water.

Exposed to the air, at common temperatures, it disappears
at the end of a certain period. Aheat of 212° Fahr. volatilizes
it without decomposition ; between 240° and 248° it enters
into fusion, and is soon afterwards decomposed, giving rise to
vapours of iodine, a deposit of very brilliant charcoal, and
hydriodic acid. A portion is volatilized at the same time. Of
all the simple non-metallic bodies, chlorine, in the state of gas,
is the only one which presents, with hydriodide of carbon, very
remarkable phenomena. ’

These two bodies scarcely come into contact before there
is a lively action, and sudden decomposition of the hydriodide ;
whence products result, whose nature varies according to
circumstances. : r

1. Ifthe chlorine, as well as the hydriodide, are perfectly dry,
there is formed a chloride of iodine, some muriatic acid, and a

eculiar white matter containing much carbon.

2. If the chlorine be in excess, there is a formation of a
solid yellow chloride ; and one of a subchloride in the opposite
case.

- 3. When the quantity of chlorine which has been made to
act upon the hydriodide has been sufficient merely to produce
a subchloride, there is no longer found in its watery solution
the above white matter, but small quantities of a liquid of an
oily appearance, which seems to grease the sides of the vessels,

300 . Progress of Foreign Science.

unites gradually at the surface of the water, and ends some-
times in falling down, and collecting at the bottom, in a drop
more or less bulky. The vessels have then a very peculiar
odour, approaching much to that of essence of turpentine.

M. Serullas at first imagined, that these two sub-
stances might be the chlorides of carbon discovered by Mr.
Faraday; but he has not been able to recognise either
of the properties by which Mr. Faraday distinguishes them,
nor are those which characterize the peculiar matters, similar to
those of the species of chloride of carbon, which may be obtained
from the action of chlorine on alcohol. It is difficult, however,
to believe that there is not an identity of composition between
these products; which will be, no doubt, modified by circum-
stances which he has not been able to appreciate.

To make the experiment of transforming the hydriodide of
carbon into the chloride of iodine, we fill a phial, having a
ground stopper, with chlorine dried over chloride of calcium,
and throwing into it some hydriodide in powder, immediately
shut the phial ; the action is speedy. There is a developement of
heat and a brisk effervescence due, he thinks, to the disengage-
ment of muriatic acid gas, which is formed. We see the liquid
red sub-chloride which also is formed at the same time, succes-
sively pass, by the absorption of chlorine, into a solid yellow
chloride. It is possible, by heating carefully the stoppered
bottle, to make the chloride pass alternately from the solid
state, to the state of a liquid sub-chloride, which, on cooling,
returns to its primitive state by resuming the chlorine which the
heat had separated with effervescence. M. Serullas has even em-
ployed this means to volatilize the chloride, from one side of the
bottles to the other, across the residuary chlorine, in order to be
sure of the complete decomposition of the hydriodide. When
we project hydriodide of carbon into flasks filled with chlorine,
we hear each time a slight noise, similar to that produced by the
immersion of a red-hot iron rod in water.

4. If the chlorine employed in these experiments is still
charged with the usual humidity which it has in coming directly
into the bottles without previous drying, the hydriodide of carbon
which we introduce equally gives rise to chloride of iodine, and
muriatic acid, but we have no longer the white matter. Thereis
formed in its place chloroxycarbonic gas (phosgene gas) which
we can insulate by inverting the bottles first over a mercurial
bath, to make the excess of chlorine be absorbed with agitation ;
then in water, in order to dissolve the muriatic acid. The
phosgene gas can remain a sufficiently long time in contact with
water without being decomposed, so as to be examined and
recognised. This circumstance of the humidity of the chlorine, to
which M. Serullas had not paid attention in his first experiments,
hindered him, for some time, from recognising under what form

M. Serullas on Hydriodide of Carbon. 301

the carbon disappeared, which he knew positively to exist in
the hydriodide.

He had occasion to observe, in these experiments, that the
sub-chloride of iodine, treated by ammonia, threw down, at the
moment, the iodine, in the state of a very fulminating iodide of
azote; and that there was formed scarcely any hydriodate of
ammonia. Wecan understand this, since the chlorine, which in
this case decomposes the ammonia, ought exclusively to seize
the hydrogen, leaving the azote to the iodine. By the common
process of putting iodine into water of ammonia, only one-
fourth of the iodine is converted into the fulminating compound.

The facility offered by chlorine, of converting the hydriodide
of carbon into chloride of iodine, and consequently into iodate
and hydrochlorate, by its solution in water, and saturation with
potash, appeared to M. Serullas, after other trials, to be the
most exact means of ascertaining the quantity of iodine which
enters into the composition of the hydriodide of carbon. He
treated a number of times with chlorine, given quantities of
hydriodide of carbon; the resulting chloride of iodine, being
dissolved in water, and saturated with potash, constantly pro-
duced the same quantities of iodate, at least with so slight
differences, that we may indicate, without fear of deviating from
the truth, 1.5 gramme as the mean product, for each gramme
of hydriodide. The iodate of potash being formed of 77.54 acid
and 22.246 potash; the iodic acid of 100 iodine and 31.927
oxygen; every gramme of hydriodide of carbon will then contain
0.8992 of iodine.

M. Serullas analyzed the compound also, by ignition with
oxide of copper; from which he infers it to consist of,

Iodine . 0.8992 1 atom
Carbon . 0.0864 2 atoms
Hydrogen 0.0144 2 atoms.

‘ 1.0000

Ann. de Ch, et de Phy. xxii. 172.
Supplementary to the above information, M. Serallas has in-
serted in the same Journal a letter to M. Gay-Lussac, on the
subject, in which he says, that he finds hydriodide of carbon may
be very abundantly obtained, by simply treating an alcoholic
solution of iodine with an alcoholic solution of caustic potash,
or soda. ‘The formation of hydriodide of carbon, in this case,
proves very manifestly the decomposition of the water; just as
the formation of an iodate with excess of acid, from the first
instants of the saturation of a solution of chloride of iodine,
seems to prove the pre-existence of iodic acid in the solution ;
and consequently to confirm its being a mixture of iodie acid

and muriatic acid, as M. Gay-Lussac has said.

302 Progress of Foreign Science.

4. On a Crystalline Matter formed in a Solution of Cyanogen.
By M. Vauquelin.

A solution strongly impregnated with cyanogen, which M. Vau-
quelin had preserved in his laboratory during the preceding win-
ter, presented a new phenomenon to him, which he had not leisure
to examine in his first experiments. At the end of about four
months, this solution, become of a slight amber hue, deposited
orange-yellow crystals, the number of which increased for some
time. When this deposition seemed to have ceased, he examined
the crystals, as also the liquor which bad produced them.

The latter had an amber colour, diffused a strong smell of
hydrocyanic acid, was alkaline, at least it suddenly restored the
colour of litmus reddened by an acid. It precipitated the sul-
phate of iron of a bluish green, which changed instantly to blue
by the addition of a drop of sulphuric acid. It is not to be
doubted therefore from these experiments that the solution of
cyanogen was converted into hydrocyanate of ammonia. It
contained likewise carbonic acid, for it precipitated lime water.

Let us next pass to the examination of the properties of the
crystals of which we have spoken, and see if by means of their
properties, we can come at their chemical composition. 1. These
transparent crystals have an orange yellow colour, which yields
a lemon-coloured powder; their form is dendritic; they have no
marked taste or smell; they are almost insoluble in water;
potash ley disengages nothing from them, nor does it dissolve
them. The mixture of these crystals and potash gives no
Prussian blue with sulphate of iron. Dilute sulphuric and
muriatic acids make them experience no alteration.

Placed on burning coals, they volatilize, diffusing a white
smoke, and a strong smell of hydrocyanate of ammonia ; leaving
a very small quantity of black matter, which can be nothing but
charcoal. :

Heated in a glass tube, closed at one end, into which he had
introduced a slip of paper dipped in sulphate of iron, they pre-
sented the following phenomena: a little moisture soon ap-
peared, the paper assumed a bluish colour; then a dull white
matter sublimed, and there remained in the bottom of the tube
only some black grains. When the tube was opened, there
exhaled a strong odour of hydrocyanate of ammonia, and the
slip of paper, when dipped into a feeble acid, took a very intense
blue colour.

As to the white sublimate, it had neither smell nor taste; it
was insoluble in water ; placed on burning coals, it was reduced
into smoke. having the odour of hydrocyanic acid. Its minute
quantity did not permit a more detailed examination, but
M. Vauquelin thinks it is of the same nature as the crystals,
minus the humidity.

Vauquelin on a new Crystalline Matter. 303

What is then the composition of these crystals? This question
is not easily answered, especially when one has at his disposal
only a very small quantity of material.

However, if we bear in mind that cyanogen formed of carbon
and azote, when decomposed in water, gives birth to hydrocyanic
acid, ammonia, carbonic acid, and charcoal, which precipitates ;
and that in the case under consideration, the same effects take
place, with the exception of the precipitation of carbon, it will
appear undoubtedly probable, that this carbon is united with a
portion of the undecomposed cyanogen, and that it is thereby
rendered insoluble; but in falling down slowly it has had time
to combine with a small quantity of water, and to assume the
crystalline form; effects due to the low temperature in which
the cyanogen was exposed during the winter. If this be the
case, we might call this substance sub-cyanogen or proto-
cyanogen.

We consider this nomenclature highly objectionable, ad-
mitting the composition to be clearly made out, which it is not.
Cyanogen and sub-cyanogen should, strictly speaking, be called
deuto-carburet and trito-carburet of azote; from which name
their composition would immediately be seen.—Ann. de Chim.
et de Phys. xx11. 132.

5. Effects of Boracic Acid on the Acid Fluate of Potash.

M. Zeise has made the observation that fluate of potash, in
which the acid was in excess, might be rendered alkaline, by a
suitable addition of boracie acid. The first portion of acid
added diminishes the acidity, the following additions make it
disappear entirely, for litmus paper is no longer changed by it;
and lastly, the saline solution took an alkaline character, and
restored to the blue colour, litmus paper which had, been red-
dened by the acid fluate of potash.

A solution of litmus reddened by the boracic acid, was mixed
with another solution of litmus reddened by the acid fluate, and
instantly a blue colour was developed; the same effects take
place by substituting soda or ammonia for potash; and it is the
same whether we employ water or alcohol to dissolve them.

Syrup of violets, reddened by the acid fluate of potash, became
blue by the addition of boracic acid, and a new quantity of acid
rendered it green. Papers, stained with curcuma (turmeric) and
Brazil wood, experienced analogous changes of colour; so that
all the re-agents seem to indicate that alkali is separated from
the acid fluate of potash by the addition of boracic acid; or
otherwise, that the fluoboric acid, which may be formed by
means of the fluoric and boracie acids, saturates less alkali,
than each of its components would neutralize alone.—Ann. de
Chim. et de Phys. xx1, 22.

Vor. XV. x

304 Progress of Foreign Science.

6. On the Hydroxanthic Acid, and some of its Products and
Combinations. By Mr. Will. C. Zeise, Professor of Chemistry
in the University of Copenhagen.

By a series of experiments on the mutual action of carburet of
sulphur, potash, and alcohol, Mr. Zeise has obtained results
which he regards as very remarkable. _,

Potash, or soda, dissolved in alcohol, may be neutralized by
carburet of sulphur, although this liquid does not change litmus
colour, and does not neutralize the alkalis in their dry state, or
when dissolved in water. This phenomenon is owing to, the
formation of a peculiar acid, by the re-action of the carburet on
the alcohol, which is determined by the alkaline body. | This
new acid contains sulphur, carbon, and hydrogen. Itis probable
that the first two elements united act in this combination the same
part the cyanogen does in hydrocyanic acid; and that they exist
in it, in a different proportion from what they do in the ordinary
carburet of sulphur. He has given the name of sxanthogen
(derived from gav905 yellow and yevv2w) to this compound radical,
because it forms combinations of a yellow colour with some
metals; and he has named the new acid, the hydroxanthic, be-
cause it is endowed with all the properties of a perfect acid.

Very pure carburet of sulphur dissolves readily in the alco-
holic solution of potash, and there instantly results a greenish-_
yellow liquid. This is easily observed by employing a solution
of potash made in the cold before it has begun to turn brown.
If, after having added enough of carburet to neutralize the solu-
tion, we expose it to a temperature approaching to 0° C., it will not
be long in yielding delicate crystals so abundantly, that we shall
soon have a concrete mass. This dried quickly between folds
of paper is the hydroxanthate of potash. It is also obtained by
evaporation of the neutral liquid, az vacuo, along with sulphuric
acid, or even by spontaneous evaporation; and also by precipi-
tation by means of sulphuric ether.

The process which he has commonly employed for the pre-
paration of the hydroxanthate of potash is briefly as follows :—
He puts one part of very pure and well calcined potash into a
glass bottle, having a ground stopper; he pours on it about 12
parts of alcohol, containing about 96 or 98 in volume of pure
alcohol ; he next digests the mixture at a temperature of about
20° or 24° C., agitating it very often for two or three hours, and
then filters the solution, Immediately afterwards he adds very
pure carburet of sulphur, till the liquor no longer reddens turmeric
paper; in order to be sure of which he puts in a little carburet
in excess, that is, till a portion of the liquid poured into water
throws up some oily globules. He now pours the liquid into
a glass capsule with upright sides. When we employ an ordi-
nary capsule, by reason of its great tendency to climb, it rises in

Zeise on the Hydroxanthic Act. 305

abundance above the edges of the vessel. The capsule is then
put immediately under the receiver of an air-pump, and a partial
vacuum is made. When it is judged that the excess of car-
buret of sulphur with a portion of alcohol has been removed, he
introduces a vessel containing sulphuric acid, and sets the pump
in full action. At the end of some time he withdraws the vessel
with the sulphuric acid, and replaces it by another of the same,
till there remains very little liquid in the vessel containing the
salt. Then, some time after, adding a little pure sulphuric
ether, he throws the mass on a filter; a little thereafter he
presses it quickly between folds of paper, and finishes the
desiccation under the air-pump receiver. In winter, or in
case we have plenty of ice at our disposal, he thinks the pre-
paration of this salt may be effected by simple refrigeration.
Evaporation in the open air has this disadvantage, that a part of
the salt commonly assumes a yellow colour, and then it yields a
solution more or less milky. We must take care not to employ
too concentrated a solution of potash in alcohol; otherwise we
obtain almost immediately a congealed mass, and here it may
happen that a trace of sulphuretted hydrogen shall be formed.

Hydroxanthate of Potash.—This salt crystallizes in needles ;
it is colourless and very brilliant; in the air, it becomes faintly
yellowish ; it has a peculiar smell; its taste, at first, extremely
cooling, becomes sulphureous and pungent. It is extremely so-
luble in water, and yet it does not attract humidity from the air.
When newly prepared it dissolves completely in alcohol, but less
copiously than in water; sulphuric ether dissolves very little of it,
and petroleum does not affect it. A solution of this salt becomes
milky by contact of air, and at the same time slightly alkaline.
Hence test-papers, which on leaving a solution of hydroxanthate
indicated no free alkali, change colour in the space of some time
in the air.

On pouring acetic muriatic, or sulphuric acid, even in a
very concentrated state, on the hydroxanthate of potash, no
effervescence takes place; but the latter two acids, diluted with
four or five waters, separate from it a liquid which is heavier
than water, and in aspect perfectly resembling an oil. This is
the hydroxanthic acid.

Barytes water, muriate, or nitrate of barytes, muriate of lime,
sulphate of magnesia and alum, form no precipitates in a watery
solution of the hydroxanthate of potash; sulphate of zinc, nitrate
or acetate of lead, deutochloride or deutocyanide of mercury,
produce white precipitates. With sulphate, nitrate, or muriate
of copper, it occasions a precipitate of a very beautiful yellow
colour. Chloride of antimony, nitrate of bismuth, deutochloride
of tin, protochloride of mercury, and nitrate of silver, form also
with it precipitates, which are of a yellow colour.

The precipitates by nitrate of silver, or protochloride of mer-

X 2 :

306 Progress of Foreign Science.

cury, pass speedily from yellow to black ; we can obtain even
immediately black precipitates with these re-agents, if we employ
yery concentrated solutions. The precipitate by sulphate of
zinc becomes slightly greenish on exposure to air. The others
do not change their colour either in air or water. None of them
effervesces either with the sulphuric or muriatic acid.

A solution of hydroxanthate of potash, very neutral, enclosed
in a vessel which screens it from the action of the air, may be
heated during half an hour at a temperature of 60° C. without
losing its characteristic properties. But, if before heating it, we
haye rendered it alkaline by an addition of potash, it will soon
acquire the property of precipitating the salts of lead black.

If we gradually heat the hydroxanthate of potash enclosed in
asmall retort, communicating with a receiver, from which a tube
passes into a mercurial bath, the following circumstances take
place: Before the temperature is raised beyond 60° C, the salt
appears to undergo no change; when heated more strongly, it
yields oleaginous vapours, fuses with a strong effervescence,
producing abundance of gas and vapours, and is transformed
into a mass of a blood-red colour. The vapours soon condense
into a liquid, which has the appearance of oil. The red matter
hardly changes its colour on cooling. On exposing this sub-
stance to a higher temperature than that at which it was pro-
duced, it enters anew into an effervescing fusion, blackening at
the same time, and giving rise to much oil and a little gas. But,
at the end of some time, the frothing ceases; and finally the
mass, quietly melted, produces neither oil nor gas, even ata
temperature not far from that of a cherry-red. On allowing the
mass then to cool, it divides itself into two portions, of which
the lower is manifestly crystalline, of a black grey, and a lustre
almost metallic ; whilst the upper layer, of a nearly black colour,
has no crystalline texture. If the fire be pushed so as to keep
the mass red for some time, it will not furnish the crystallized
part. The gaseous product appears to be of the same kind
during the whole course of the decomposition; the same holds
true of the oily matter. The first is distinguished by an ex-
tremely strong odour of onions or leeks; but, in other respects,
it comports itself (at least in trials with contact of water) like a
mixture of carbonic acid gas and sulphuretted hydrogen.

Xanthic Oil.—This liquid is limpid, and of a yellowish colour.
Its odour (which resembles neither that of carburet of sulphur
nor sulphuretted hydrogen) is very strong, and adheres strongly
and for a long time, to every body which has been impregnated
with it. Its taste is at once saccharine and pungent. Water
appears to dissolve it in very small quantity; alcohol, when
diluted even to a great degree, dissolves it in abundance. The
alcoholic solution is disturbed by a certain quantity of water;
but, if not too much loaded with oil, it becomes clear, on the

Zeise on the Hydroranthic Acid. 307

addition of a greater quantity of water. Xanthic oil does not
affect the colour of litmus or turmene; it acts in no manner on
nitrate of lead; it does not cause a precipitate with muriate of
copper. At the approach of a flaming body, it readily takes fire,
burns with a bluish flame, and gives rise to much sulphureous
acid, mingled undoubtedly with carbonic acid. Water is con-
densed on the sides of a bell-glass suspended over the flame.

The red matter is deliquescent ; dissolves completely in water;
the solution is at first reddish, but soon becomes yellowish-
brown. It strongly reddens turmeric. Alcohol acts but slowly
on this substance.

The watery solution of the red matter, recently made, preci-
pitates the salts of lead red; but commonly the precipitate
becomes soon’ black; the cupreous salts are precipitated of a
black-brown*. It does not occasion a precipitate with the
salts of barytes; but a solution of the nitrate of barytes is
coloured yellow. It makes a lively effervescence with acids,
giving rise to an odour of sulphuretted hydrogen mingled with
that of carburet of sulphur,—and there are, at the same time,
separatéd globules of an oleaginous liquid ; but no precipitate
of sulphur takes place. A slip of paper imbued with nitrate of
lead, and then exposed to the gas disengaged by muriatic acid,
is coloured partly black and partly red. When exposed to the
air, the red matter passes a little towards yellow.

The crystalline matter speedily deliquesces, and it dissolves
in water without leaving any residuum. The solution is of a
very intense brown-black, so that, before diluting it to a certain
degree, the liquid appears nearly opaque ; it becomes turbid on
contact of air; and sulphuretted hydrogen, as well as a little
sulphur are disengaged from it by acids. The matter treated
with a red heat, seems analogous to a mixture of sulphuret of
potassium with charcoal.

Hydroxanthate of potash, thrown on a glass-plate, red hot, rea-
dily takes fire, and burns quietly with a bluish flame; but if we set
fire to it at the point of the flame of a candle, it burns with much
energy, emitting sparks extremely brilliant. This somewhat
singular phenomenon is, probably, due to flocks of charcoal,
formed and projected by a partial decomposition of the salt,
when it is exposed to a very strong heat which penetrates
into the interior of the mass.

M. Zeise has prepared hydroxanthates of soda and ammonia,
with alcoholic solutions of these alkalis and carburet of sul-
phur; hydroxanthates of barytes and lime, with the carbonates of
these bases and hydroxanthic acid. The hydroxanthate of
lime may also be obtained, but with difficulty, in a state of

* The solution is in this respect very similar to that obtained, according
to M. Berzelius, by digesting for a long time in the cold an aqueous solu-
tion of potash with carburet of sulphur ; or by adding carburet of sulphur
to a watery solution of hepar.—Ann, de Ch, et de Phys. xx, 243,

308 Progress of Foreign Science.

purity, by decomposing a very concentrated alcoholic solution
of hydroxanthate of potash, with an alcoholic solution of
chloride of calcium. He thinks it probable that the greater
part of the precipitates, produced by decomposing the me-
tallic salts with hydroxanthate of potash, are combinations
of xanthogen with the metal of the salt employed. The
precipitate from copper is not attacked either by sulphuric
or muriatic acid, whether concentrated or dilute; nitric acid,
however, (specific gravity 1.32,) dissolves it easily, with a pro- ~
duction of gas, and a substance which has the aspect of fat,
at first coloured greenish-yellow, then whitish-yellow. The
xanthide of lead is prepared with nitrate of lead and hydroxan-
thate of potash; it is white, and falls down in flocks. Xanthic
oil is given out on exposing these two xanthides to heat in a
retort.

Hydroxanthic acid is liquid at common temperatures, and
even under them; it has completely the appearance of a trans-
parent colourless oil. Its specific gravity is greater than that
of water. It does not combine with this liquid. On contact of
air it is soon covered with a white opaque crust. When much
divided among water, it is completely destroyed in a short time.
Its smell is strong and peculiar. It has at first an acid taste,
then a very strongly astringent and bitter one. It reddens
powerfully litmus paper, but a portion of the red is not long in
becoming yellowish-white. To obtain hydroxanthic acid we
introduce the hydroxanthate of potash into a long and nar-
row glass; we pour into it sulphuric acid, diluted with four or
five volumes of water, aiding the re—action by a gentle agita-
tion; two or three minutes afterwards, we add to the milky
mixture, at intervals of some seconds, from three to four
volumes of water, so managing it that the new acid may collect
into a single mass at the bottom of the vessel; then we add
speedily fifty or sixty volumes of water. It remains now only
to withdraw the water, and to pour on new portions as speedily
as possible; to withdraw this, and so in succession, till the
washings no longer affect a solution of barytes. Instead of
sulphuric acid, we may equally make use of the muriatic.

Hydroxanthic acid dissolves very readily in a watery solution
of potash, barytes, or ammonia; it expels carbonic acid from
the carbonate of potash, giving birth to a salt which entirely
resembles that obtained by neutralizing an alcoholic solution of
potash with carburet of sulphur. With carbonate of ammonia
it furnishes hydroxanthate of ammonia, with disengagement
of carbonic acid. It decomposes, also, carbonate of barytes,
forming hydroxanthate of barytes, which is very soluble in
water and alcohol. The re-action is, in general, much more
lively when the salifiable bases or their carbonates are intro-
duced in the solid state, into hydroxanthic acid, covered

Braconnot on a Green Colour. 309

with a little water, than when we employ their solutions, which
is undoubtedly owing to the insolubility of the hydroxanthic
acid in water. Black oxide of copper, yellow oxide of lead,
red oxide of mercury, each, when introduced into the hydroxan-
thic acid, under water, are quickly converted into xanthides,
which nowise differ from those procured by precipitation, With
oxide of mercury the action is very lively.

Hydroxanthic acid takes fire in the air instantly, on the
approach of a burning body, occasioning a strong odour of
sulphurous acid. When exposed to heat, in a suitable vessel,
it is decomposed at a temperature much below that of boiling
water; and there appear to be formed carburet of sulphur, and
an inflammable gas. No odour of onions, or of sulphurous acid,
is manifested.

Iodine was employed for ascertaining whether this new acid
contained hydrogen, and the results show that it does. When
iodine is introduced into newly-prepared hydroxanthic acid,
covered with water, there is manifested instantly a lively
action; the iodine is set in motion on the surface of the acid,
and is dissolved. The acid becomes in part opaque, and is
coloured at first yellow, then brown,—so that we have soon at
the bottom of the vessel an oleaginous liquid of a red-brown ;
but, after a little time, the colour begins to disappear, and, in
the space of some minutes,) provided too much iodine has not
been added,) there results a liquid, oily, opaque, and faintly
yellow. The watery liquor, which floats over the oleaginous
liquid, is almost colourless ; it is more or less milky,—but, b
means of a filter, we obtain it perfectly limpid. When tried b
the proper tests, this liquor is found to be a solution of hydriodic
acid. The oleaginous liquid which remains, when we have
treated hydroxanthic acid with a sufficient quantity of iodine,
no longer yields xanthide of copper, with a sulphate of this
metal. Comparative trials were made. with carburet of sulphur,
iodine, and water; the iodine combines with the carburet,
colouring it violet; but, as might be presumed, no trace of
hydriodic acid is produced.—Ann. de Chim. et de Phys., xxi. 160.

7. On avery beautiful Green Colour. By M. Henri
Braconnot.

M. Noel, who has a fine manufacture of painted paper at
Nancy, sent M. Braconnot a superb green colour, known in com=
merce for some years, in order that he might analyze it. A ma-
nufacturer of colours at Schweinfurt was said to possess the sole
secret of its preparation, Of all the methods tried by M. Bra-
connot to obtain this colour, the following succeeded best :—He
dissolved six parts of sulphate of copper in a small quantity of
hot water ; and, on the other hand, he boiled in water six parts
of arsenious acid, with eight parts of the potash of commerce,

310 Progress of Foreign Science.

_ till no more carbonic acid was expelled. He mingled, by
degrees, this hot solution with the first, agitating constantly till
the effervescence ceased; a dirty greenish-yellow precipitate
fell in abundance. To this he added about three parts of acetic
acid, (three parts of which saturated 0.45 of carbonate of lime,)
or such a quantity as that there was a slight excess of it, per-
ceptible to the smell after the mixture. The precipitate gra-
dually diminished in size; and, at the end of some hours, there
was deposited spontaneously at the bottom of the liquor (now
colourless) a powder, somewhat crystalline, and of a fine green
colour. He separated the supernatant liquid, which, by resting
longer on the colour, might deposit oxide of arsenic, which
would render it paler. He afterwards treated it with a large
quantity of boiling water, to remove the last portions of arsenic,
beyond what existed in combination. We must take care not
to add to the solution of sulphate of copper an excess of
arsenite of potash, because it would saturate, in mere waste,
the acetic acid, which ought to be in slight excess in the mix-
ture, without causing any very obvious effervescence. in it.
For this reason, it is proper, in general, to take a neutral
arsenite of potash. It is true that a portion of the arsenious
acid remains in the mother liquor; but this may be employed
for the preparation of Scheele’s green, commonly used for painted
papers of an inferior quality. It appeared that, when M. Bra-
connot added to the mixture, before the fine green colour was
pronounced, a small quantity of the latter ready formed, the
production of it was more speedily promoted,—as a crystal,
plunged in a saline solution, attracts the molecules similar
to its own.

The process now described has been repeated on the great
scale, and with some modifications, at the manufacture of
M. Noel. An arsenite of potash was employed, which had been
prepared with eight parts of oxide of arsenic instead of six.
The liquors were concentrated. Some hours after the mixture,
a pellicle, of a very rich green colour, formed at the surface.
The whole being exposed to heat, a heavy powder fell down,
which was washed with abundance of water, to free it from the
excess of arsenious acid. The green thus obtained was magni-
ficent; and several unprejudiced colourists judged it to be
more powerful than that of Schweinfurt.—Ann. de Chim. et
de Phys., xxi. 53.

8. On the Combinations of Chromic Acid with Potash.
By M. F. Tassaert, fils.

This gentleman affirms that a solution of chromate of potash,
whether neutral or alkaline, will not yield crystals of a neutral
salt, which salt can exist only in solution ; and that, in reality,
the lemon-yellow salt, known in commerce under the name of

Tassaert on Chromate of Potassa. 3ll

the neutral chromate of potash is a subsalt, for repeated washings
and crystallizations do not deprive it of the property of restor=
ing the blue colour to reddened litmus paper. In attempting
to form the neutral chromate, he found that, when he employed
a solution of chromate containing nitre, even in small quantity,
this could be easily separated by adding to the liquors an excess
of alkali. On subsequent concentration, the whole of the nitre
crystallized in well-formed prisms, carrying down with it but a
small quantity of chromate; whilst if we saturate first of all
the solution of chromate, so as to make it neutral, and after-
wards evaporate, since the salt thus formed and the nitre have
nearly the same degree of solubility, they fall down together
in crystals, and can no longer be separated: but the contrary
takes place when the neutral chromate is converted into, a sub-
salt, it thus becomes much more soluble, and lets the nitre
form first.

This difference of solubility between the acid chromate and
the subchromate of potash, is very well marked; for if into a
saturated or nearly saturated solution of alkaline chromate, we
pour some drops of acid, there is immediately formed an abun-
dant deposit of acid chromate. To free the salt completely
from nitre, he recommends it to be deflagrated with charcoal in
a crucible; and afterwards to be dissolved, filtered, and, crys-
tallized. M.Tassaert analyzed the chromates of potash, by
drying them for several days in a temperature of from 50° to
60° C., precipitating their acid by acetate of barytes, washing
the barytic salt, and adding to the supernatant liquid, sulphuric
acid in excess; evaporating and igniting the sulphate of potash..
He thus found that the acid chromate, which is. naturally
formed in the neutral solution, is composed of

Chromic acid . . . . 67.40
Potash. atileus, jerolbooan 32.60

while the alkaline salt consists of

Chromic acid. . . . . 52.0
POfase hy oe os. 40.0

It is to be observed, that chromate of barytes begins to dissolve
in water, the moment that we remove from it the whole of the
acetate of barytes that it contains mixed with it: it then dis-
solves in sufficient quantity to colour yellow the filtered liquors.
A single drop of acetate of barytes, mixed with the edulcorat-
ing water, stops the dissolving process, and, renders the filtered
liquid turbid. Water, with a little alcohol, equally prevents
this solution.—Ann. de Chim. et de Phys., xxii. 51.

9. Analysis of different Limestones, by M. P. Berzelius,
Ingénieur des Mines.

After giving a table of analyses of French limestones, not fit

312 Progress of Foreign Science.

for water-mortars, which is of too little interest in this king-
dom for us to copy, he next presents us with the following table
of analyses of hydraulic limestones.

Carbonate of lime 0.900 0.858 0.892 0.890 0.890 0.825 — 0.792 0.765 0.800 0.840
— magnesia 0.050 0.004 00.30 0.020 0.020 0.041 — 0.025 0.030 0.015 ——

—iron. . —— 0.062 —— ——- —— —— — 0.060 0.030 —

Silica. . 2. 2. —— —— ——— ——- ——— -—S— ~— 20.065 0.116 0.170 0.100

=>) Alumina. . . 0.050 0.054 0.078 0.090 0.090 0.134 — 0.038 0.036 0.010 0.050
oy Oxide Of iron. 6) — SO eS ee 010
Charcoal. . . —— 0.022 —— —- ——- —— — 0.020 —- —— —
Wer ec Si me rn ee ee 0.010 ——

pS 2 ea Se ee eee eS
1.000 1.000 1.000 1.000 1.000 1,000 — 1.000 0.992 1.005 1.000

The first five are called moderately hydraulic; the last six very
hydraulic.

No. (1.) Limestone of Vougy (Loire,) between Roanne and
and Chaulieu; sublamellar, yellowish, full of ammonites, and
other shells. It gives a very good lime, which sets in water.
(2.) Limestone of St. Germain, (Ain,) compact, of a deep grey,
veined with white limestone, lamellar, and penetrated with
gryphites. It is employed at Lyons, for water-works. (3.)
Limestone of Chaunay, near Macon; compact, in fine grains,
yellowish-white ; it is of the secondary formation, and is em-
ployed in the fabrication of a lime, which is hydraulic. (4.)
Limestone of Digna (Jura); compact, penetrated with plates of
limestone, and having imbedded a great number of gryphites,
of a very deep grey. It produces lime which takes a good
hold, and may be considered as hydraulic. (5.) Limestone,
which accompanies the preceding, and which enjoys the same
properties ; compact, in grains nearly earthy, of a bright grey
colour. (6.) Secondary limestone of Nismes (Gard) ; compact,
yellowish-grey ; yields a hydraulic lime, which passes in the
country for being of excellent quality. (7.) Lime of Lezoux,
(Puy de Déme,) fabricated from a marly fresh-water limestone.
It is called excellent. It produces an abundant jelly, with
acids. (8.) Compact limestone, the locality of which is un-
known. It gives a very good hydraulic lime. (9.) Second-
ary limestone of Metz (Moselle); compact, in grains almost
earthy, of a bluish grey, more or less deep. The lime which
it produces is known to be hydraulic. (10.) Marly limestone
of Senonches, near Dreux (Eure et Loire); compact, very ten-
der, crushes between the fingers, absorbs water very readily.
It forms a paste with this liquid, nearly like clay, but it does
not fall into powder, when calcined. This lime is very cele-
brated, and is much employed at Paris.. (11.) Mixture of four
parts of the chalk of Meudon, and one part.of the clay of Passy,
in volume, which M. Saint-Leger employs to make artificial
hydraulic lime, in the manufacture of it, established near the
military school. The government uses at present only the lime

_Berthier on Limestones. 313

of M. Saint-Leger, in the public buildings of Paris. An im-
mense consumption of it was made last year, for the canal of
St. Martin; it has been judged superior to the lime of Se-
nonches, a superiority of which M. Berthier has convinced him-
self by experiments on the small scale. It is sold at the price
of 60 francs the cubic metre.

M. Berthier enters into a pretty full account of the Roman
cement of Parker and Wyatt of London. The following is his
analysis of the English stone, from which, by a regulated calci-
nation, and subsequent pulverization, it is formed :

Carbonate of lime. . . 0.657

magnesia . 0.005
a iron . . . 0.070
————-— manganese . 0.019
Cla Silieas fine ontos 100180
Alumina. . . . 0.066
Waters) ai dean andi osi0013

—-_

1.000

Lime produced by the above.
BANE, SO! C1 F24 VILE ONS | OEE
Magnesia. . . . . . 0.000
Clay SOaRUp, SIE keg SENSED
Oxide of iron . . . . 0.086

1.000

The English stone is compact, of a very fine grain, hard, tough,
capable of taking a fine polish, and of a grey-brown colour.
Its specific gravity is 2.59. It is said to be got in tubercular
masses, in marls. There is a similar stone at-Boulogne. M.
Berthier thinks, that with one part of common plastic clay,
containing no sand, and two parts of chalk in bulk, which cor-
responds to one part of clay to 2£ parts of chalk in weight, a
very good hydraulic lime could be made, which would set as
speedily as the English. He acknowledges, however, that it is
not probable we can obtain by mixtures, hydraulic limes which
can acquire so great hardness and _ solidity as the natural mor-
tar, because these qualities depend, not only on the composi-
tion of the substance, but also on its state of compactness. We
can conceive, that the greater density a hydraulic lime pos-
sesses, which slakes without changing volume, the greater fa-
cility its particles will have to become aggregated, and the less
shrinking will there be in its consolidation. Whatever, there-
fore, we may do, the artificial mixtures will be always lighter
than the natural stones.

The following general inferences, which M. Berthier draws
from some subsequent experiments, are important. A limestone
which contains 6 per cent. of clay, affords a lime already per-

314° Progress of Foreign Science.

ceptibly hydraulic; when the clay is present in the proportion
of 15 to 20 per cent., the lime is very hydraulic; finally, the
lime sets instantly, and may be regarded as Roman cement,
when the limestone contains from 25 to 30 in the 100 of clay.
He considers the iron and manganese as useless towards the
hydraulic effect. To appreciate the qualities of a limestone,
relative to the kind of lime which it can furnish, it is suffhi-
cient to determine the quantity of alumina and magnesia which
it affords.
10. Observations on Mortars.

In a mortar which owes its solidity to the adhesion of the
lime to the alloys, (the substances mixed with the slaked lime,)
there is evidently an advantage in multiplying as much as
possible the surfaces of contact, and consequently in employing
a pulverulent alloy; but, the mortar in that case requires a
larger proportion of lime than when we take a granular alloy.
On the other hand, the alloys with large grains do not afford
mortars so solid as the pulverulent alloys, because there remain
among the grains of the alloy spaces filled with pure lime,
which do not present the same resistance to fracture as the
parts occupied by the alloy. It thus appears evident, that to
obtain with the smallest possible quantity of lime, mortars
which shall possess the maximum of solidity, we must employ
alloys which contain particles of different sizes and pulverulent
parts, avoiding always the mixture of argillaceous substances,
which can form a paste with water, and which of themselves
possess no coherence. M. de Saint-Leger made last "summer,
trials on the great scale, the results of which coincide perfectly
with these views. He found, contrary to the common opinion,
that the sand usually employed at Paris, gives a better mortar,
when it is merely washed, than when the fine particles are
separated by means of a sieve.

The pozzolanas, both artificial and natural, differ extremely
in their composition ; they resemble one another only in the
power they possess of absorbing water without softening; a
power due to their porosity. It is probable, therefore, when
they act on lime in a peculiar manner different from other
alloys, such as quartzose sand, pounded glass, Sc., it is to
their porosity, as M. John imagines, that they owe this pro-
perty. The important observation made by M. Vicat, that
clay slightly baked is an excellent alloy, whilst the same sub-
stance strongly calcined is a very indifferent one, supports the
same opinion ; for clay slightly baked, and that strongly cal-
cined, differ from each other only in this, that the first is light,
porous, and capable of absorbing water, whereas the last has
become compact and altogether similar to a stone, by the effect
of its contraction, which the high temperature has caused it

Vauquelin on a new Aérolite. 315

to undergo. In other respects they are both in quite another
state from raw clay, since they do not contain combined water,
and can no longer form a paste with this liquid.

It is known that porous bodies have the faculty of ab-
sorbing and condensing rapidly a great number of gaseous
substances. May it not be, because they act in this manner on
the carbonic acid contained in the atmosphere and in water,
that they have the property of accelerating the condensation
of certain mortars? We may thus conceive why they produce
this effect with a rich lime, whilst with poor or very hydraulic
limes, they give no better result, than non-porous alloys; for,
the mortars of rich limes owe their solidification only to the
regeneration of carbonate of lime, while the solidification of
the mortars of very hydraulic limes is independent of this
cause.

To the above remarks we may add, that the English stone,
from which Roman cement is made, is a ferruginous marl, in
spheroidical concretions, called septaria or ludi Helmontii; a
description of which is to be found in our common chemical
works.—Ann. des Mines.

11, Analytical Examination of Touch-stone. By M. Vauquelin.

This stone, lapis lydius, is usually arranged in the works on
mineralogy, in the sequel of the Cornéennes stones, without
being entirely confounded with them. (It is the schistous
jasper of Brogniart, and a sub-species of rhomboidal quartz of
Mohs.) The specific gravity of the touch-stone of M. Vau-
quelin is 2.465. It whitens before the blow-pipe, exhaling a
feeble sulphurous acid odour. The fragments which before
calcination are crushed on glass, afterwards scratch it easily.
It has no action on the magnetic needle. Acids in the coid
exercise no perceptible action on a mass of touch-stone ; but, if
we heat mutiatic acid on the mineral reduced to a fine powder,
there is instantly disengaged a very manifest odour of sul-
phuretted hydrogen ; a little iron is dissolved, and the acid
becomes yellow. ‘The residuum, which is considerable, seems
to have become blacker by this operation. ;

The alkalis easily dissever the principles of touch-stone.
With potash the fusion, at a red heat, is easy and very liquid,
like that of siliceous stones... The mass becomes of a greyish-
yellow. M. Vauquelin satisfied himself. by means of ignition
with chlorate of potash, that the black colour is owing to
carbon; the quantity of which he determined from the volume
of resulting carbonic acid. From. the smell evolved by the
action of potash on the mineral, he infers the presence of a
small quantity of ammonia in it; which seems to be in the
state of a muriate. He could not estimate its amount. The
presence of sal-ammoniac, charcoal, iron, and sulphur, says

316 Progress of Foreign Science.

M. Vauquelin, may put geologists in the way of imagining the
origin and mode of formation of this singular mineral produc-
tion. The discovery of a quantity of this stone, of good qua-
lity, would be of great importance, adds he, to the goldsmiths ;
for it is rare, and extremely high priced.

Analysis. First Specimen, Second Specimen.
Silica viattiypoiis; 85.00 69.00
Alumingd y0)te7}o10994) 12200 7.50
Lime STITOD, EH 100 a trace
Charcoal ioe icy 34412;70 3.80
Sulphur... . 0.60 a trace
Metallic iron . . . 1.70 17.00
1 ITs A a Ree a le i 5 97.30
LLGSS eel. tag ca ee

100.00

Ann. de Chim. et de Phys. xxi. 317.

12. Examination of an Aérolite which fell in the neighbour-
hood of Epinal on the 13th Sept. 1822, at the entrance of the
forest of Tauniére, three quarters of a league from la Baffe
(Vosges.) By M. Vauquelin.

This stone is in appearance like the ordinary aérolites; but _
is distinguished by the great quantity of metallic iron, and the
small quantity of sulphur that it contains, By acting on its
powder, with muriatic acid, and transmitting the evolved gas,
through solution of acetate of lead, slightly acid, he had a pre-
cipitate of sulphuret of lead ; from whose quantity he inferred
that of the sulphur present. What was insoluble in muriatic
acid, he washed on a filter, and afterwards calcined with caustic
potash. The fused matter assumed a greenish tint. The mu-
riatic solution was treated with gaseous chlorine, to peroxidize
the iron, which was then thrown down with ammonia. From
this. precipitate, he separated the manganese and the minute
quantity of magnesia, which might fall along with it by sul-
phuric acid. The following are the results on four grammes :

In 100 parts.

Silteay minsine daaieh bel Ao 35.00
Oxideyof irons: spe olf 2.51 62.75
Sulphur ...... - 0.09 2.25
Oxide of chromium . 0.01 0,25
nickel... 0.02 0.50
Magnesia .... 2. 0.17 4.25
Lime and potash .. 0.50 1.25
4.70 106.25

The 2.51 parts of oxide of iron correspond to 1.76 of metal ;

Saussure on the Action of Flowers. 317

but the 0.09-of sulphur require 0.16 of metallic iron to form a
proto-sulphuret ; and if we deduct besides 0.18 for the 0.25 of
oxide of iron, obtained from the chromate, there will remain
1.42 of metallic free iron, containing only the nickel and the
manganese. Of the fall of the above aérolite, some account is
given in this Journal. xiv, 448.—Ann. de Chim, et de Phys.
xxl. 324,

CHEMISTRY OF ORGANIZED BODIES.

13. Analysis of the Fruit of Areca Catechu. By M. B. Morin,
Apothecary.

The tree called areca catechu by Linnzeus, grows abundantly
in the Molucca isles, in Ceylon, and ‘several other of the south-
ern countries of Asia. Its constituents are; 1. Gallic acid;
2. A large quantity of tannin; 3. Acetate of ammonia; 4. A
peculiar principle analogous to that found in the leguminous
plants ; 5. An insoluble red matter; 6. A fatty matter, composed
of elaine and’stearine ; 7. Volatile oil; 8. Gum; 9. Oxalate of
lime ; 10. Ligneous fibre; 11. Mineral salts ; 12. Oxide of iron
and silica. \ Journ. de Pharm.’ Oct. 1822. p, 455.

14, On the Action of Flowers on Arr, and on their Temperature.
By M. Theodore de Saussure.

The flowers, even of aquatic plants, do not develope them-
selves in media deprived of oxygen gas; they require for the
support of their vegetation a greater proportion of this gas than
the rest of the plant. The green parts are often so abundant in
the leaves, that they can of themselves form the atmosphere
necessary to their existence ; but it is not so with the flowers.

Several among them, as the rose, preserve, it is true, their
corolla for a shorter time in the air than in vacuo or in azotic
gas; but, when we expect to withdraw them still fresh, they
éxale an unwholesome smell, their petals are corrupted, and
we perceive that this apparent life concealed a real death,
while the fall of the blossom in the air is only an effect and a
proof of vegetation.

When we place a flower under a receiver full of air, and shut
by mercury, it changes little or nothing the volume of the air,
while oxygen is present. It absorbs this gas, replacing it by
a nearly equal volume of carbonic acid; nearly, because occa~
sionally there is observed in the air, a slight diminution of volume,
owing to porous absorption. M. de Saussure has not been able
to find any trace of hydrogen in the air in which flowers have
vegetated. His first trials made him imagine that they exhaled.
a small quantity of azote ; but he has not confirmed this result.
In estimating the quantity of oxygen destroyed by flowers, he
weighs the latter, and takes their specific gravity as equal to
that of water. The volume of oxygen consumed, is referred to

318 Progress of Foreign Science.

the volume of flowers or leaves taken for unity. Thus the
number 8.5, which expresses in the table, the quantity of
oxygen gas destroyed by the Trope@olum majus, denotes that a
cubic centimetre, or a gramme weight of these flowers (deduct-
ing the peduncles), destroyed 84 cubic centimetres of oxygen
gas, which were replaced by 83 cubic centimetres of carbonic
acid, in 200 cubic centimetres of air. The duration of the ex-
periments, or the abode of the flowers and leaves under the
receiver, was 24 hours. All the following results were ob-
tained in summer, sheltered from the direct action of the sun,
at a temperature between 18° and 25° cent. The quantity of
oxygen destroyed by the flowers, is greater in the sun than in
the shade ; arise of temperature also augments this destruction.
He has inscribed on the table, the hour when the flowers were
plucked, and placed (with their stalk in a very little water)
under the receiver; this period is especially important for those
which blow but a short time, and which expand only at a cer-
tain time of the day, as the hibiscus speciosus, cucurbita melo-
pepo, and the passiflora serratifolia. Only flowers, entirely de-
veloped, and in perfect vigour, were submitted to experiment ;
characters which are recognized particularly by the stamina.

Names of thecitiowers Oxygen gas consumed|Oxygen gas consamed

by the flowers. by the leaves,

Single gilliflower (red) Cheiran-

thus incanus, 6 in the evening. ie 4,
Double gilliflower, idem. 7.7
Single tuberose (Polyanthes tu-

berosa) 9 A. M. 9, 3.
Double tuberose. Idem. 7.4
Trozpolum majus (single) zdem. 8.5 8.3
Double ditto. idem. 7.25
Datura Arborea 10 A. M. 9. a
Passiflora serratifolia, 8 A. M. 18.5 8.5

Carrot, (umbels of) Daucus ca-

rota, 6 P. M. 8.8 7.5
Hibiscus speciosus, 7 A. M. 8.7 5.1
Hypericum Calycinum 8 A. M. 7.5 7.5
Cucurbita melo-pepo (male

flowers) 7 A. M. TZ, 6.7

Ditto. (female flowers,) idem. B
White lily, 11 A. M. 5. 2.5
Typha latifolia 9 A. M. 9.8 4.25
Fagus Castanea, 4 P. M. 9.1 8.1

. The results here given indicate that in equal volume the
flowers usually destroy more oxygen than the leaves in obscu-
rity, or than the rest of the plant; for the leaves destroy much
more than the stems and the greater part of fruits. The differ-

Vauquelin on the Excrement of Serpents. 319

ence is more striking, and subject to fewer exceptions, as we
shall show further on, if we consider in the flower merely the
stamina. A single genus of flowers, that of the arum, has
presented a phenomenon very worthy of attention, by a pro-
duction of heat hitherto unknown.

15. Examination of the Excrements of Serpents, exhibiting in
Paris, of the Boa Species. By M. Vauquelin.

His experiments prove, that the excrements are merely uric
acid without any mixture, except a little ammonia, potash, and
animal matter; and are consequently produced from the urine
like that formerly discovered in the excrements of birds. But
the true excrements of the serpents are not of the same nature as
those now spoken of ; for others were given him only of feathers
slightly changed, and bones become very brittle and deprived
almost entirely of their gelatine ; which proves that feathers,
that is the horny texture, is, of all animal matters, the most
difficult to digest.

The first species of excrement issues from the body of the
animal, in the form of a pap, resembling chalk or starch diffused
in a little water. Sometimes they come forth in a concrete
mass, like a calculus. This proves that the urine of serpents
dwells, like that of birds, in a sort of reservoir, called cloaca,
where it is inspissated.—Amn. de Chim. et de Phys, xxi. 440.

Vou. XV. Y

320

Art. XII. ANALYSIS OF SCIENTIFIC BOOKS.

I, An Elementary Introduction to the Knowledge of Mineralogy ;
comprising some Account of the Characters and Elements of
Minerals; Explanations of Terms in common use ; Descriptions
of Minerals, with Accounts of the Places and Circumstances in
which they are found ; and especially the Localities of British
minerals. By Witttam Puitiipes, F.L.S., M.G.S.,L.&C.
&c.&c, &c. Third edition, enlarged.

Tue third edition of this work has just made its appearance,
and we congratulate the mineralogical public on the acquisition.
The merits of the two former editions, (especially the second),
have stamped a character on the book, ‘that nothing we can say
in its praise, can enhance, and have rendered its plan and contents
so familiar to the cultivators of mineralogy, that it would be super-
fluous to attempt, in this place, a detailed account of them.
Taking it for granted, therefore, that few mineralogists, who under-
stand English, are unacquainted with the second edition, we shall
proceed to show in what respects the present differs from its pre-
cursors, and point out the alterations, additions, and improvements,
which its indefatigable author has introduced into it.

For this purpose, we shall begin by quoting some passages
from the Advertisement, prefixed to this third edition.

The most important additions and improvements that have been made,
consist, first, in the introduction of notices or descriptions of about eighty
minerals, of which the greater part have been discovered since the publi-
cation of the preceding edition ; secondly, in the insertion of the results |
obtained by a careful examination of most crystalline minerals, as regards
their structure and cleavage; thirdly, in the addition of a figure to the
verbal description of most substances found in a crystallized state, represent-
ing the primary form, and another the secondary planes in connexion with
those of the primary crystal, together with such measurements of the planes
as I have been able to obtain, chiefly by means of the reflective goniometer
of Dr. Wollaston; in the fourth place, advantage has been taken of 2
translation of Berzelius’s excellent work on ‘‘'The use of the Blowpipe in
chemical analysis, and the examination of Minerals, by J. G. Children,
F. R.S., L. and E., &c.” in so far as relates to the more simple experiments
with that useful assistant to the student, in recognising minerals ; and,
fifthly, the meanings of the names by which minerals are commonly known
in this country, are mostly given at the foot of the page, centaining the
description, except where, being chemical, they manifestly have been
derived from the composition of the substance.

In regard to arrangement, no alteration has been made in this edition,
except where new and more satisfactory analyses demanded a change : on
the subject of the arrangement therefore, it seems requisite only to add that,
having in the first instance adopted it, as being in my own estimation the
most advantageous to the student that I could devise, the experience of its
utility now induces me to recommend it to him as an instructive method of
placing the minerals in his cabinet.

In this advice, we fully concur, and we believe that the
mode of arrangement recommended by our author, has already
obtained very general adoption. Since it is a consideration of

Phillips on Mineralogy. 321

primary importance, we shall briefly state its outline, as, notwith-
standing our conviction that the work is in the hands of almost
every mineralogist, there may be one or two unacquainted with it ;
and to such, if such there be, the statement must be useful.

The basis of the arrangement is chemical, and since certain
substances are found to occur in very large proportion in those
rocks which, geologically, are usually considered to be of the
oldest formation, the close alliance between geology and mine-
ralogy suggests the order, in which each class of minerals may be
taken.

Some of the earths chiefly constitute those rocks which are esteemed to
be of the oldest formation; while others do not enter into the composition
of rocks, being found only in the veins which traverse them; these, there-
fore, (as veins are considered of posterior formation,) may be estimated as
being of later origin than the former.

Of the alkalies and acids as mineral constituents, either combined with
the earths or with each other, the former claim the precedence, as entering
into the composition of the oldest rocks.

Two or three of the metals occur in small quantity in the masses of some
of the earlier rocks ; but in general the metals are found in veins ; some in
veins traversing the older rocks, and rarely or never in those of a newer
kind; others most abundantly, or only in those of newer formation.

As rocks are constituted chiefly of earths, and metals are principally
found in veins, earthy minerals may be assumed to be.of earlier origin than
the metalliferous.

Proceeding according to this assumed relation in the respective
ages of the mineral elements, and beginning with the most simple,
and ending with the most compound substance, our author places
silica at the head of his list, ‘‘ because it is estimated that silex
forms the largest proportion of the oldest and most abundant of
the primitive rocks ; and all earthy minerals, of which silex is the
largest ingredient, are arranged under that head ; beginning, che-
mically, with silex in its purest forms, and proceeding to such as
consist of that and another earth, as silex and alumine; then to
those consisting of silex and lime, &c.; and afterwards to such mine-
rals as are chiefiy constituted of three or more earths, terminating
with the most compound; and regarding the iron, manganese, &c.,
involved in many of them only as accidental ingredients ;” because
they do not alter the external form, and internal structure of those
minerals.

The other earthly minerals are proceeded with in like manner; arbitrarily
selecting such as contain the rare earth glucine, and placing them under
that-head, except that the gadolinite, which also contains the still more rare
earth yttria, is placed under the latter. )

Next after those minerals which consist only of one or more of the earths,
succeed those in which one or other of the alkalies is found ; to these, such
of the acids as occur in the concrete state; then those minerals which are
primarily constituted of one or more earths and an acid ; and, after these,
those consisting of an alkali and an acid; and, finally, the very few in which
an earth, an alkali, and an acid are combined together.

Then follow those minerals (chiefly earthy) which have not been ana-
lyzed, or of which but little is known.

_ The native metals and metalliferous minerals succeed, arranged accord~-
ing to the order of age and formation; subordinately beginning with the

322 Analysis of Scientific Books.

metal in its native state, when it so occurs; then its combination with
other metals, when in the state of a natural alloy; then combined with
sulphur ; with oxygen ; and, finally, as an oxide combined with an acid.

The combustibles follow, beginning with sulphur, to which succeeds
carbon in its purest form, and afterwards its several combinations with
other bodies, as the base of the greater part of all the substances belonging
to this class.

The order of arrangement is therefore as follows:—

Earthy minerals.

Alkalino-earthy minerals.

Acids.

Acidiferous earthy minerals.

Acidiferous alkaline minerals.

Acidiferous alkalino-earthy minerals.

Minerals (chiefly earthy) which have not been analyzed, or of which
but little is known.

Native metals, and metalliferous minerals.

Combustibles.

In our opinion, this is at once the clearest and best arrangement
hitherto suggested. Founded on the only rational basis, compo-
sition, it is so skilfully subdivided, that no confusion exists in any
part of it. In point of convenience, too, in cases of hasty reference,
the essential elements of any mineral are seen instantly by casting
the eye on the running title at the top of the page, where its
description occurs. It is hardly necessary to insist on the supe-
riority of the preceding arrangement to that abominable violation
of all chemical truth, which has placed crystallized carbon at the
head of the earthy minerals!

With respect to the figures of the crystalline forms which accom-
pany the descriptions, and which are neatly and accurately exe-
cuted in outline on wood, Mr. Phillips informs us, that the
measurements annexed to them are to be considered only as
approximations to their true value, especially of the secondary
planes; ‘for in no instance has it been attempted to correct the
geometry of nature by a resort to the more rigid laws of calcu-
lation. It has been ascertained, by a comparison of the measure-
ments taken from similar and brilliant planes of different crystals,
that, owing to some natural inequality of surface, the same precise
angle is rarely obtained, and hence those given in the succeeding
pages cannot be expected to be absolutely exact.” The error,
however, rarely exceeds forty minutes, and is frequently not more
than one or two minutes; and when the measurements of the
primary form have been obtained from cleavage planes, (which is
noted in the descriptions,) ‘* they may be considered as approxi-
mating the truth much more nearly than when taken by means of
the natural planes.”

Where the regular solids, as the cube, regular octohedron, &c.,
are the primary forms, our author has adopted the measurements
given by Haiiy, and denotes them by the letter H annexed ; but,
where the primary formis not one of the regular geometrical solids,
as the oblique, and doubly-oblique prisms, and the very numerous
class of rhombic prisms, he has determined their true measure-
ments by ‘* subjecting the planes obtained by cleavage to the re~

Phillips on Mineralogy. 323

fiective goniometer—a more certain method than that adopted
by Haiiy ;” who always, we believe, used the goniometer in-
vented by Corangean.

In regard to the figures to which the measurements are annexed, it may
be observed, that these are not in all cases the representatives of single
crystals, for in some of them are associated the planes observed on two or
three : thus occasionally rendering the form more complicated than any
single crystal 1 have seen, but not more so than may probably be found
hereafter. This mode has been adopted as offering to the student the
greatest assistance that I could devise, since it combines at one view all
the observed planes, without increasing enormously the bulk, and conse-
quent expense of the work, as must have been the case if all the varieties
of form had been given separately.

We had some doubts, on first reading the preceding passage,
whether this assembling of planes from different crystals into one
sum total may not rather tend to perplex, than instruct the student.
On further reflection, however, we are inclined to think our author
is right, since a reference to the simpler forms, including the
primary, of which a series of smaller figures generally accom-
panies the larger, will sufficiently elucidate the more complex,
and, in some degree, imaginary, yet still possible, structure; and,
in some instances, the planes on an actual crystal are so numerous,
that nearly all that are represented on the large figures are dis-
cernible. Thus our author mentions a crystal of fluor, from
Devonshire, in his own possession, which exhibits all the planes,
except four, represented in the elaborate, and beautifully-distinct
figure given at page 170, and would, if perfect, be bounded by
322 planes. If the figure we have just referred to was drawn by
no “ other rule than such as the hand and eye could furnish,” as
our author tells us the figures generally were, his hand and eye
possess a skill and accuracy very seldom indeed to be met with.

In the useful introduction which precedes the mineralogical
descriptions, not much alteration has been made in the present
edition; the division which relates to analysis has been somewhat
shortened, and, as well as the summary account of the elements of
minerals, improved by a few judicious changes in point of arrange-
ment, and in such other particulars as the progress of chemical
science during the last four years has rendered necessary. The
hypothetical wodanium is, of course, struck out altogether, and
amongst the other essential alterations we are glad to see selenium
removed from the list of metals, and restored to its more proper
association with sulphur, phosphorus, and boron. Mr. Phillips
remarks, both in this and the second edition, that we have no de-
scription of the iron pyrites from Fahlun, in which this substance
is found. If it have any decided external characters, by which it
may be distinguished, it is very desirable that they should be pub-
lished, for we strongly suspect that many a specimen of common
pyrites is sold as seleniferous, which does not contain an atom of
selenium, We have ourselves witnessed, more than once, a lively
competition for the purchase of such a specimen, said to be from

324 Analysis of Scientific Books.

Fahlun, between two or three ardent collectors at an auction, till
the price of the precious lot ran up enormously; whilst, from its
perfect resemblance to some we had once an opportunity of exa-
mining, we felt confident, that it was quite guiltless of concealing a
particle of selenium in its whole composition. The pyrites usually
said to be seleniferous, is of a bright yellow colour, a small grain,
and generally very friable.

As a specimen of the elaborate figures which accompany many
of the descriptions, we annex a copy of that which Mr. Phillips
has given of Humite*. We have selected this mineral for our pur-
pose, because,—Ist., its form has never been described before. 2dly,
Count Bournon, in his Catalogue, says that all its planes are
striated, whereas not one of them is so; for what he mistook for
striz, are, in fact, so many planes, as has been proved by sub-
jecting the crystals to the reflective goniometer. 3dly. It shews,
therefore, the value of that instrument in a striking degree, and
that the use of it quickens the sight of the observer, who, while
measuring without a glass, finds planes, where an old, and generally
supposed accurate, observer saw only strize.

Humite.—Bournon.

It occurs in very small crystals, which are of a deep reddish-
brown colour, and transparent or translucent, with a shining lustre.
The crystals are modified in an extraordinary degree; their primary
form may be considered as being a right rhombic prism, of 60° and
120°, but they yield to mechanical division, parallel only to its
shorter diagonal: (i. ¢., to the plane h of the following figure.)

Primary.

* Humite. In honour of Sir Abraham Hume.

Phillips on Mineralogy. 325

MonM 120 00/hond 4 119 24/h——i2 140 56
PonMorM 90 00 d5 121 45|- i3 143 20
fork 90 00} ——d6 125 30}clond1 155° 2
M onk 120 00] ——d7 _ = 129 46 d5 159 10
dl 118 12}———d8 | 121 20 d7 159 30

or Morf 150 00}———-d9 124 2{dlong3 116 25
PonCl 144 1]——d10 136 16|d12o0nd8 163 22

c2 153 45|——d11 157 20 g3 131 15
hona 90 00} ——-g 3 100 40/b2o0ng3 143 15
di 101 50} ——-g 2 103 40/41lonM _ 137 00
—d2 103 42; ——g1 115 15|fona 115 10

—d3 112 45 i1 133 36

It is found on Somma, with brownish mica.

The letters on each plane of the larger figure are placed accord-
ing to the system of notation adopted by Mr. Brookes in his Fami-
liar Introduction to Crystallography, of which we propose to give
our readers an account in our next number. In the mean time
we fully agree with Mr. Phillips in ‘* recommending it strongly to
the student, as being calculated to teach the interesting science on
which it treats in its most pleasing form;” and we will add, as
ably as pleasantly.

We should do our author injustice, if we were not to mention
that the verbal description of the Humite is much shorter than the
generality of the descriptions contained in the work. The hardness,
specific gravity, chemical composition, and the principal characters
of each substance before the blow-pipe, are, in most cases, care-
fully stated ; and that they have been omitted in the description of
Humite, is owing, we conclude, partly to its scarcity, and partly
because it occurs only in minute, and, usually, separate crystals,
wherefore the two first characters are hardly attainable, and we are
not aware that any accurate analysis of this mineral has hitherto
been made.

As only one plane of cleavage has yet been noticed, the primary
form has necessarily been deduced from the nature and direction
of the secondary planes, which, although perfectly consistent with
the right rhombic prism, (the primary form adopted by Mr. Phil-
lips,) are equally compatible with the assumption of a right rect-\
angular prism for the primary form, in which case P, f, and h,
would be the primary planes.

The utility of connecting the primary and secondary forms, as
is done in a variety of instances throughout the work, is obvious ;
and a little attentive consideration will convince the observer of
the manner in which the various secondary planes are allied to the
primary crystal. Thus in the figure annexed, the planes f replace
the obtuse lateral edges of the prism, and incline equally on M and
M ; the planes 4, in like manner, replace the acute lateral edges ;

326 Analysis of Scientific Books.

the planes a, lying between f and P, replace the obtuse solid angles,
while c 1 and ¢ 2, lying between A and P, replace the acute solid
angles. The planes d 1 to d 12 replace the terminal edges of the
crystal, lying on the acute solid angles, in pairs, one of each pair
being in the front, and the other on the back of the crystal. The
planes 4 1 and 6 2 also lie in pairs, but on the obtuse solid angles,
each pair being in sight, but only one of each is numbered, The
planes 2 1, 2, 3 are in pairs, replacing the aeute lateral edges, one
of each pair only being in sight; while the planes g 1, 2, 3 tend
to replace the obtuse lateral edges, being also in pairs, visible in
the figure on each side of the plane f.

The getting-up of the present edition is a considerable improve-
ment on the second ; the paper is much better, the type clearer,
and the general appearance of the book neater and more elegant.
The size of the work renders it a very convenient travelling com-
panion, and the able manner in which a vast quantity of information
is condensed into a small compass, makes it equally serviceable in
the cabinet or the carriage.

Il. Traité Elémentaire des Réactifs, leurs Préparations, leurs Em-
plois spéciaux, et leurs Applications dU Analyse. Par MM. A.
Payen, Manufacturier; et A. CH&vaLLIeR. Paris, 1822.
8vo. Pp. 224.

Ir we except the fourth volume of Thenard’s Trazté de Chimie,
there is no comprehensive system of rules delivered by modern
writers for accomplishing these two great objects of chemistry—
synthesis to effect analysis, and analysis to effect synthesis. The-
nard is, however, excellent, in as far as he could be supposed to
discuss so extensive a matter in 225 pages of rather open letter-
press. He classifies under the six distinct heads of gases, com-
bustible bodies, products of combustion, mineral salts, mineral
waters, and vegetable and animal substances, the various subjects
of analytical research ; conveying judicious precepts for the elimi-
nation of the different constituents of a compound, and for ascer-
taining their proportions. In a short concluding chapter he de-
scribes the processes by which we may discover to what class of
bodies, and consequently to what chapter of his instructions, any
unknown substance is to be consigned. Of the estimation in which
M. Thenard’s system of analysis is held in this country, no better
evidence need be adduced than the fact of two independent trans-
lations of it into English having been executed by very able hands.
It is equally respected in France.

However valuable it may be, as a summary digest of analytical
methods, its limits necessarily preclude many details of great in-
terest and impertance. We were, therefore, well pleased to observe
the announcement of the work, whose title is prefixed to the present

Traité Elementaire des Réactifs. 327

article. Its authors have been for some time active contributors to
the Journal de Pharmacie. M. Payen, who is a manufacturer of
sal ammoniac, lately wrote a good memoir on the discolouring
properties of charcoal, to which the second prize was awarded by
the Pharmaceutical Society of Paris. M. Chevallier published
some time since an Analysis of the Mineral Waters of Pontivy ;
and the two gentlemen conjoined, inserted in the Journal de Phar-
macie for September last, Experiments on the colouring matter of
the Petals of the Malva Silvestris, and of the wood of St. Lucie
(Cerasus Malaheb) employed as reagents, in which they sought to
appreciate numerically their sensibility to alkalis and acids, com-
pared with other coloured tests.

We were accordingly willing to expect, in a new: treatise on
chemical tests, published in the French capital, some novelty in the
agents, or some ingenuity in their applications ; something, in fact,
to justify the appearance of such a work soon after the third edition
of Thenard. But we are sorry to acknowledge that our expecta-
tions have been greatly disappointed.

MM. Payen and Chevallier have not, in reality, indicated any
method of re-agency which is not better described in the Professor’s
treatise; while they seem to be unacquainted with many things
which had been long ago effected in the same department by Berg=
man, whose treatise on the analysis of mineral waters, as far as
his plan required, presents more minute and delicate rules of testing
than we can find in the recent Traité.

The work is inscribed, in terms of merited respect, to M. Vau-
quelin, under whose superintendence they profess to have made
their chemical studies. We wish they had consulted some of his
excellent formulz of analysis, from which they might have gleaned
many ingenious tests.

In a short introduction they give a definition and description of
the term re-agent, to which they subjoin the plan of the subsequent
book. ‘‘ Re-agents,” they say, ‘‘ are bodies which, placed in
contact with others, give rise to’ new combinations; and which,
during their re-action, produce peculiar and characteristic pheno-
mena, which serve to make these bodies be recognised.” Many
things, however, which it would be difficult to bring under the
above definition, are certainly re-agents ; such as change of tem-
perature, (or heat,) electricity, and magnetism. We would, there-
fore, say, that a chemical re-agent or test is a known body or
power, which, being applied to an unknown substance, serves to
point out, by characteristic phenomena, its nature or constituents.

Their work is divided into nine chapters. In the first they treat
of the forms of bodies, of specific gravity, of the influence of bodies
foreign to the combination, of the action of light and electricity.
The second chapter discusses caloric, its action on different bodies,
and the phenomena to which it gives rise. The third treats of the
employment of simple combustible bodies non-metallic and me-

328 Analysis of Scientific Books.

tallic, and of the hydrated oxides. The fourth describes the com-
binations of simple combustibles with the metals, ‘The fifth con-
siders the bodies which result from the combination of acidifiable
principles with hydrogen or oxygen; viz., acids. To this chapter
an appendix is subjoined, in which the combination of hydrogen
with oxygen, and that of hydrogen with azote are discussed.
Water and ammonia are here meant. The compounds resulting
from the combination of the acids with the salifiable bases (salts),
occupy the sixth chapter. The seventh is devoted to animal and
vegetable products. In the eighth the manner of preparing and
preserving the re-agents described in the preceding chapters is
treated of; and the ninth contains some examples of the applica-
tion of re-agents to analysis.

It is by no means our intention to follow the steps of our authors
through their tedious common-places ; nor shall we expend cri-
ticism on their vicious arrangement. We would rather use their
work as the vehicle of communicating some practical remarks on
the important subject which they have, without due preparation,
taken in hand to discuss.

Analytical chemistry may be simply qualitative, or it may be
likewise quantitative. To apply the former to an untried form of
matter is an exercise of invention, and success in it is the prero-
gative of chemical genius. In this department, a mind guided by
the routine of rules will be frequently at fault. To determine pro-
portions is, perhaps, more irksome and laborious ; but, for the most
part, it requires much less ingenuity. Circumstances may occur,
however, where the research of quantities may call forth no little
invention. Two of the best examples to this purpose are to be
found in Sir H. Davy’s work on Nitrous Oxide and M, Gay-
Lussac’s Memoir on Prussic Acid.

Re-agents, as extemporaneous indicators, belong chiefly to qua-
litative analysis; but they may, without the use of the balance, by
due care, throw considerable light also on quantity, This two-
fold application of tests was much considered by Bergman and
Kirwan ; but it has been almost wholly overlooked by MM. Payen
and Chevallier.

To describe a chemical body is merely to detail its relations to
other forms of matter, supposed to be previously known. An
enumeration of these relations constitutes, therefore, the properties
of the body. Hence a re-agent is a known substance, which, pos-
sessing some marked relation to another substance, serves, by its
action with it, to ascertain its general and specific place in a che-
mical arrangement. In this extended sense the electroscope, com-
mon and voltaic, as well as the magnetic needle, and some optical
instruments, deserve to be ranked among tests, though the term is
usually restricted to chemical agents.

We conceive that the proper order of discussing the subject of
chemical tests would bes first, to describe in succession the various

Traité Elémentaire des Réactifs. 329

substances entitled to this distinction, insisting particularly on the
criteria of their purity ; for the chief part of the mis-statements and
contradictions to be found in chemical works, has been occasioned
by the employment of impure re-agents. The details of their pre-
paration should be referred to the ordinary systems of chemistry.
After pointing out the means of verifying the justness of the tests,
we should next detail their applications, stating fully the pre-
cautions to be observed in their use, and the peculiar phenomena
which they produce with their correlative objects.

The second part of the treatise should present in a systematic,
and, if possible, in a tabulated form, the various objects of chemi-
cal research, simple and compound, with their corresponding tests.

In the third, and concluding division, formule illustrated by
examples, somewhat in detail, should be given, for evoking in suc-
cession the several constituents of a compound by the successive
application of their appropriate re-agents.

Mess. Payen and Chevallier have incurred for their treatise the
blame of confusion and tautology, by adopting a defective arrange-
ment. In their second chapter we have an account of the action
of heat on a long list of substances, placed in alphabetical order ;
which account would have been better introduced under the de- .
scription of the various bodies in subsequent chapters. No use,
however, is made of the indications of Berzelius. ‘The rambling
manner in which our authors-sometimes indulge themselves, in
trite details, may be judged of from the following specimen:

Tin melts at 228° centig. At a much higher temperature it is reduced
into vapour: when elevated to a red heat, if we throw it on the hearth it is
divided into incandescent globules, which burn less vividly than those of
antimony. It is distinguished, further, from this metal, because it leaves a
greyish oxide, heavier than its oxide. Tin is susceptible by the action of
heat of being totally oxidized, if we take care to remove the oxide in pro-
portion as it forms on the surface of the metallic bath. By this oxidation
the metal augments in weight. Brun, apothecary at Bergerac, is the first
who took notice of this phenomenon ; not knowing the cause of it, he con-
sulted Jean Rey, physician, who replied, that “ the air had become fixed
in the metal.” This bold reply should have put people in the way of seeing
the composition of the atmospheric air. 1t was long afterwards, however,
before its composition was discovered. P. 20.

What they are pleased to say of the blow-pipe is extremely
vague, shewing that they were unacquainted with Berzelius’s in-
structions for the use of this admirable test, a subject which they
dismiss with a foot-note reference to his Traité sur le Chalumeau,
They speak indeed of the different intensities of heat in the different
parts of the flame, but never hint at the opposite powers of oxida-
tion and reduction which it possesses; the most important discovery
ever made in the science of the blow-pipe.—See our Extracts on
this subject in vol. xiii. p. 325, of this Journal ; as also Children’s
Berzelius, pp. 29 and 49.

The third chapter is of great length. It treats of simple com-
bustibles and their oxides. We shall take a cursory view of some
of its particulars, We find chlorine recommended for demon-
strating the presence and proportion of sulphuretted hydrogen, by

330 Analysis of Scientific Books.

‘
the precipitation of sulphur which it occasions in this gas. But
the sulphur will not be precipitated in an insulated form, provided
enough of chlerine be present. A chloride is the result. Chlorine,
when put in contact with carburetted hydrogen, is said to seize the
hydrogen, and set the carbon free. But the formation of chloride
of carbon renders the above test nugatory.

On turning to their eighth chapter, on the preparation and pre-
servation of re-agents, we find it stated that 200 volumes of chlorine
are soluble in 100 of water ; and that this solution= 24° on Baumé’s
hydrometer, corresponding to the specific gravity 1.2. This is a
serious error. The above proportions reduced to weight are, 168
chlorine to 1 of water; so that were the total volume of the liquid
to remain without increase, its specific gravity would be only
1.006. When the water of chlorine possesses this density or one
greater, we may be sure that it is contaminated, probably with mu-
riatic acid. They say that 133 parts of muriate of soda, with 110
of sulphuric acid, and 100 of oxide of manganese, should afford
80 of chlorine. But 133 parts of salt require for decomposition
106 of acid, leaving only four parts of acid, instead of 110, for satu-
rating 100 parts of peroxide of manganese. Instead, therefore,
of eighty parts of chlorine, from the above erroneous propor-
tions, little more than forty will be obtained.

When hydrogen is disengaged from dilute sulphuric acid by the
agency of zinc, it is properly enough directed to be passed through
a solution of potash to deprive it of sulphuretted hydrogen, They
take no notice of Berzelius’s elegant application of hydrogen gas, as
a test of oxygen in bodies; nor of a similar application of chlorine
gas in the examination of certain ores.—See this Journal, xiii. 156;
and xiv. 209.

Their process for procuring iodine is good for nothing ; and
when they prescribe a solution of this active body in alcohol to be
kept as a test, they forget the production of hydriodic acid, which
never fails to occur. The solution in alcohol should be, therefore,
an extemporaneous prescription. That, or the watery solution, is a
very delicate test of the presence of starch in plants, or in their
products. A blue or purple colour is produced.

Bright silver is recommended as the test of sulphuretted hydro-
gen in mineral waters. They justly observe, in describing the
process for obtaining the metal pure, that its precipitated chloride
should be mixed with caustic potash, instead of the alkaline car-
bonate, which, during the ignition, is apt to scatter the particles of
silver, and prevent them running together into a button at the
bottom of the crucible. Tin affords the best criterion of a tungstate.
When the metal is plunged into a solution of the salt, a blue pre-
cipitate falls, which has not been examined. Messrs. Payen and
Chevallier prescribe, after Bergman, for the analysis of cast iron, to
measure the bulk of hydrogen evolved during its solution in dilute
sulphuric acid. They affirm that one gramme of iron should yield
in this way 458 gramme measures of hydrogen, at 52° F. and

Traité Elémen'aire des Réactifs. 331

29.9 barom. pressure. By our calculation, one gramme of iron
should afford only 424 gr. measures of hydrogen.

Pure zinc must be sought for by reducing to the metallic state the
oxide thrown down from the purified sulphate. When this metal is
employed to separate copper from its saline solutions, we must re-
member, that it precipitates this metal from the nitrate chiefly in
the form of a subnitrate.

In the preparation of lime-water, we are rightly desired to reject
the first portions of the solution, which may contain some
saline matter. Lime-water is the usual test of corrosive sublimate ;
but hydriodate of zinc is much better. That water is also the
common test of carbonic acid in an alkaline ley. We shall see
presently that subacetate of lead is a far more delicate test. The
chief employment of magnesia as a re-agent is in vegetable ana-
lysis, where it serves conveniently to precipitate the vege-
table alkalis from their native combinations in the substance of
plants.

Liquid potash is recommended for detecting the artificial colora~
tion of wines. It affords, with these liquids, the following pre-
cipitates relative to the different colouring matters employed.

With the natural principle of wine the precipitate is green

Berries of yeble , . - violet

Indian wood . * 2 . violet-red

Mulberries F 3 5 . violet

Brazil wood . ‘ . . Ted

Beet ! B é . red

Turnsole or litmus . ; . Clear violet

Myrtle berries : ’ - wine-lees co-
lour —

Elder berries . bluish.

This test may possibly be applied with advantage to detect adul-
terations in much of the port wine retailed in this kingdom, which
is a villanous compound of malt spirit and dye-stuffs.

A separate chapter is allotted to the deuto-chloride and deuto-
cyanide of mercury, which bodies might have been better placed
among the salts.

The acids used as re-agents are discussed in the fifth chapter.
Strong acetic acid dissolves both gluten and resin. Dilution with
water throws down the resin, and saturation with an alkali preci-
pitates the gluten.

Arsenious acid is prescribed as a test of sulphuretted hydrogen ;
orpiment being formed by the combination. An arsenite is dis-
tinguishable from an arseniate by nitric acid, which throws down
from a solution of the former arsenious acid in powder.

They free iron from cobalt by means of oxalic acid; the oxalate
of the latter metal being insoluble.

Sulphite of lime is enjoined as a substance capable of arresting
the fermentation of wines, and other vegetable juices.

332 Analysis of Scientific Books.

A bar of zinc is said to answer for distinguishing the ammoniuret
of copper from that of nickel. It precipitates the copper in the
metallic state, whilst it occasions no change in the solution of
pure nickel.

For separating nickel and cobalt, they adopt M. Laugier’s pro-
cess; who dissolves the oxalates of the two metals in water of
ammonia. On exposing the solution to the air, the nickel preci-
pitates, while the cobalt remains dissolved. Thus, it is said, a
perfect separation can be effected. The details of this process
were given some years ago in this Journal; but we have since
found them practically exceptionable.

The sixth chapter treats of the principal salts, employed as
re-agents. The application of acetate of lead, to estimate
sulphuretted hydrogen, is one of the best chemical tests. The
sulphates and carbonates should have been previously removed by
nitrate of barytes. From the weight of the sulphuret of lead, the
quantity of sulphur, amounting to =, may be computed; to
which fraction, if we add =};, the sum will denote the weight of
the sulphuretted hydrogen. Another very general use of acetate
of lead is, the separation of the acids from vegetable juices, or in-
fusions. On exposing the saturnine salt to a current of sul-
phuretted hydrogen gas, the lead is converted into a sulphuret,
and the vegetable acid remains free. By the same acetate, the
tartaric acid is distinguished fromthe pyro-tartaric, the former yield-
ing a precipitate of tartrate of lead ; while the latter acid remains
in solution. Acetate of lead is sometimes used as a test of sul-
phuric acid; but it is not very delicate. It will not detect
sede» 2 quantity sensible to litmus infusion, or even pale litmus
paper. Paper, imbued with acetate of lead, is a convenient test
of sulphuretted hydrogen. Sub-acetate of lead is incomparably
the nicest re-agent for detecting carbonic acid, or a carbonate, in
solution. The same salt serves to separate picromel from the
bile. For this purpose, we pour into that animal product, first,
acetate of lead in excess. The whole of the yellow matter and
the resin, fall down, in union with the oxide of lead. This oxide
carries with it also, the phosphoric and sulphuric acids, which
exist in the bile, in the state of phosphate and sulphate of soda.
The liquor being filtered, and the precipitate washed, we pour into
the clear solution sub-acetate of lead. The excess of oxide in
this salt combines with the picromel, and is deposited with this
substance, in the form of yellowish-white flocks. These being
thrown on a filter, and repeatedly washed with water, are to be
dissolved in dilute acetic acid, and the solution is to be exposed
to a current of sulphuretted hydrogen. The lead falls down in
the state of sulphuret. By evaporating the supernatant liquid,
pure picromel is obtained.

MM. Payen and Chevallier mention a ready method of

Traité Elémentaire des Réactifs. 333

ascertaining the proportion of alcohol in wines, beer, cider, &c.,
long agodescribed by Mr. Brande, to 100 parts in volume of the
liquid : to be tried, 12 parts of solution of sub-acetate of lead *
are to be added; a precipitation ensues which is rendered general
by slight agitation. On filtering, a colourless fluid, containing the
alcohol, is procured. By mixing with this dry carbonate of potash,
(calcined pearl-ash,) as long as it is dissolved, we separate the
water from the alcohol. The latter is seen floating above in a
well-marked stratum; the quantity of which can be estimated at
once, in a measure tube. Sub-acetate of lead is also employed
for precipitating mucus in a flocky form, from its mixture with
gelatine, which is not affected by the salt.

Borax, in coarse powder, or small lumps, is much employed
by the French chemists, for separating muriatic and sulphurous
acids from other gaseous bodies.

To detect lime in sugar, muriate of ammonia in powder is mixed
with it, and heated. Pungent ammonia exhales. For the separa-
tion of alumina from its solution in an alkaline ley, sal ammoniac
is the proper re-agent. A muriate of potash is formed ; while the
ammonia and alumina are both disengaged.

Under muriate of barytes, nothing is said, of the numerical
power of this test of sulphuric acid. According to Kirwan, a
solution of this salt produced a very sensible precipitation in
water that contained only 5;¢4-s5 of real sulphuric acid. Ace-
tate of lead is ten times less sensible to this acid; while nitrate
of lead, as well as nitrate and muriate of strontian, are far inferior
tests, When the acid is combined with a base, as in sulphate of
soda, the barytic salt is 11 times less sensible, even after two or
three hours of re-action, than with the free acid. According to
Bergman, solution of muriate of barytes immediately discovers
about +;355 of combined sulphuric acid, or 745, in two or
three hours, The same test took twenty-four hours to’ detect one
grain of sulphate of lime in 6000 of water.

Where boracic acid is suspected to be mixed with sulphuric,
in a mineral water, muriate of strontian is a convenient re-agent,
as it throws down the latter without affecting the former acid.
In general, when muriate of barytes is applied to measure the
amount of sulphuric acid, we should digest the precipitate in
nitric acid of moderate strength ; then wash, dry, and ignite. Thus
the phosphate, borate, malate, tartrate, &c., will be removed. *

Muriate of potash is prescribed for distinguishing tartaric from
citric acid; for when it is added to a solution of: the first, small
brilliant crystals of bitartrate of potash fall; with the last acid, no
change ensues.

« This solution is made by boiling 15 parts of pulverized (and calcined)
litharge, with 10 of acetate of lead, in 200 of water, for 20 minutes, and
concentrating the liquid by slow evaporation to one half; it must be kept
in well-corked phials, quite full.

334 Analysis of Scientific Books.

Proto-muriate of tin converts the molybdic into the molybdous
acid; and therefore occasions with it, and molybdate of potash, a
characteristic blue precipitate.

Nitrate of silver is capable, according to Bergman, of detecting
<zisy of common salt in water; after standing some time, it
would discover a much smaller quantity. According to M. Pfaff,
proto-nitrate of mercury is a still more sensible test of muriatic
acid. One part of muriatic acid, specific gravity 1.15 (equivalent
to 0.283 of chlorine) diluted with 70.000 of water, is scarcely
rendered feebly opalescent by the nitrate of silver; and when the
dilution amounts to 80000, the effect is null. But the sensibility
of proto-nitrate of mercury is such that even 5554555 of muriatic
acid at 1.15, is indicated by a slightly chill shade in the water.
MM. Payen and Chevallier maintain the superior delicacy of the
silver test.

Proto-nitrate of mercury is said by Pfaff to be the most delicate
re-agent for ammonia; one part of this alkali, diluted with 30000
of water, is indicated by a faint blackish-yellow shade, on adding
the mercurial solution. Proto-nitrate of mercury may also be
used for detecting phosphoric acid; the precipitate being re-
dissoluble in nitric or phosphoric acid, which chloride of mercury
is not.

Nitrate of silver serves to distinguish kinic from the other vege-
table acids. The salts of the first acid do not disturb the trans-
parency of the nitrates of silver, mercury, or lead. One grain of
oxalic acid, according to Bergman, detects one grain of lime in
42250 of water. Oxalate of ammonia is, however, the suitable
form of applying this test; MM. Payen and Chevallier say that it
is sensible to ss4p7 of lime.

In the seventh chapter of their treatise, where vegetables and
animal reagents are described, we find the following table of the
solubility of some fixed oils in alkohol of specific gravity 0.817,
at the temperature of 54°. 5 F.

Oil of sweet almonds 0.003
Beech mast . . . 0.004

Linseed’ 8.10.5." 2° 10.006
Hazel-nuts . . . 0.003
Common nuts . . 0.006
Olives 2°") 25% >. 010038

Poppies . . . . 0,004
Ditto, one year old . 0.008

In applying starch as a test of iodine, if the latter be combined
with a base, we must liberate it by the addition of an acid, as the
muriatic. After this, +545; of iodine may be rendered manifest
by a violet or purple colour.

Animal charcoal deprives vegetable juices not only of their
colour, but also removes the whole lime which they may contain ;

Traité Elémentaire des Réactifs. 335

a property of great consequence in the purification of beet-root
sugar. "
To distinguish a very small quantity of essential oil in a distilled
water, a few drops of solution of muriate of gold. are employed.
The metal is reduced by the oil, and falls down in a violet powder.
Or coloured tests for acidity and alkalinity, MM. Payen, and
Chevallier give us less definite information than we had expected.
The alcoholic infusion of wild mallow petals, yields by evapora~
tion, a colouring matter, which dissolved in. water, is. sensibly
greened by a water containing s57¢555 of hydrate of potash, or
to0o00 Of hydrate of soda. Lime water, with 10 additional
waters, is the limit of dilution at which the mallow paper can be
affected ; but with 25 waters, the mallow infasion is still greened,
Water boiled on calcined magnesia and then filtered, is capable of
affecting the same test. ett bo
Litmus paper, according to Bergman, is sensible to,+3!57 of free
sulphuric acid in water ; but not to a less proportion.. The tincture
or litmus is, however, much more sensible. When a drop of
water impregnated with carbonic acid is applied to strongly dyed
litmus paper, no change ensues, because the alkali of the litmus is
adequate to the saturation of the minute quantity of that acid ina
drop of the liquid; but the same water when poured into a weak in-
fusion of litmus, reddens it perceptibly. In MM. Payen and Ceyal-
lier’s paper on the wood of St. Lucie, it is stated that water contain-
ing 3;/55 of sulphuric acid just reddens paper stained violet with
an infusion of the fruit of that wood; but the infusion itself is
sensible to acid diluted to z5455- Litmus paper is said to be
sensible to ;4455, and the tincture is a still more delicate test.
Paper, stained red with infusion of Brazil wood, is an excellent
re-agent for distinguishing several acids from one another.—See
the extract of M. Bonsdorfi’s Memoir in this Journal XIV. 226.
Paper stained yellow with turmeric is browned by water contain-
ing =3;; of dry carbonate of soda; but it must be some time
immersed in the liquid. This test is, however, of little use in
determing alkalinity, since Mr. Faraday has shewn that it is liable
to be browned by strong acids, as also by the boracic, by the
green sulphate and muriate of iron, sub-muriate of zinc, super-
nitrate of bismuth, diluted chloride of antimony, of a strong
solution of muriate of manganese, muriate, sulphate, acetate, and
nitrate of uranium, and muriate of zirconia. See this Journal
XIII. 315, XIV. 234. Rhubarb colour has similar fallacies, Mr.
South shewed long ago, that subacetate of lead reddens turmeric.
Brazil wood is a pretty delicate test of alkalis; but it is blued
by waters containing earthy carbonates, and sulphate of lime.
Water holding in solution +5 ,4555 of dry carbonate of soda, affects
Brazil wood paper. Kirwan says, however, that it is not affected
by water impregnated with 54, of selenite. Reddened litmus
paper is blued by water which contains 1, of dry carbonate of
soda, according to Bergman. Infusion of red cabbage or of violets,
Vou. XV. Z

336 Analysis of Scientific Books.

and paper stained with their colours*, are also good tests, of acid
and alkali; but less sensible than the preceding.

The ninth chapter of MM. Payen and Chevallier’s work treats of
the application of different re-agents to analysis; here we find little
worthy of remark. ‘Their instructions are neither so systematic nor
so precise as those given by M. Thenard. The method of detecting
magnesia, invented by Dr. Wollaston, and published long ago by
his lamented friend, Dr. Marcet, inthe second edition of Saunders
on Mineral Waters, is briefly mentioned by our authors. The
elegant manner in which the inventor practises this process on the
smallest scale, having been somewhat vaguely described by
M. Clement, in the Annals de Chimie et de Physique, for July,
1822, we shall take the liberty here of detailing it more precisely.

Dissolve in a watch-glass, at a gentle heat, a minute fragment
of the mineral. suspected to contain magnesia, dolomite for ex-
ample, in a few drops of dilute muriatic acid ; to this solution, add
oxalic acid, to render the lime that may be present insoluble ;
then pour in a few drops of a solution of phosphate of ammonia t.
Allow the precipitate to settle for a few seconds, and decant a
drop or two of the supernatant clear liquid on a slip of window-
glass ; on mixing with this liquid two or three drops of a solution
of the scentless carbonate of ammonia, an effervescence takes
places ; draw off to one side with a glass rod, a little of the clear
solution, and trace across it, with the pressure of a point of glass
or platina, any lines or letters on the glass plane ; on exposing this
to the gentlest possible heat (as making a little warm water flow over
it), white traces will be perceived wherever the point was applied.
These consist of the triple phosphate of ammonia and magnesia.

The whole of this beautiful analytical operation, as performed
by Dr. Wollaston, occupies less time than we have taken to write
the formula. In the application of this process on the larger scale,
the carbonate of ammonia should be added first, which prevents
the chance of any simple phosphate of the earth being formed,
To estimate the quantity of magnesia present in any compound,
we must consider, according to Dr. Marcet, every 100 grains of
the triple salt dried at the temperature of 100° F. to be equivalent
to 19 of earthy base. If we calcine the salt at a red heat, so as
to expel all the water and ammonia, an earthy phosphate re-
mains, which, according to Dr. Murray, contains 40 per cent. of
magnesia. ‘The theoretic proportions of the bi-phosphate of mag-
nesia are 70 acid + 25 base, or 73.68-+ 26.32 in 100 parts, and of the
neutral phosphate 35 acid+25 base, or 584-4412 in 100 parts.

Nitrate of mercury has been lately prescribed as a test for
examining sophisticated olive oil; it is prepared by dissolving in
the cold 6 parts of mercury in 74 parts of nitric acid, specific

* The blue petals of the iris or water-flag, afford a good test colour either

by infusion or by rubbing them on paper. Radish colour is transferred in
the latter way, and forms a pretty aelignte test paper.

+ Phosphate of soda may likewise be used.

Traité Elémentaire des Réactifs. 337

gravity 1.36. This solution when added to oil of grains (as poppy
seed oil) leaves it liquid, while it solidifies oil of olives.

We have occasionally adverted in our Journal to the defective
and confused notions entertained among the continental chemists
about the atomic theory, which, in every useful point of view, is
the offspring and growth of this island. The following paragraph,
translated from this treatise on re-agents, affords a curious con-
firmation of our opinion.

Dr. Wollaston, in the construction of the scale of equivalents, did not
believe that he could make the numbers tally with the atomic theory ; ac-
cording to which, Mr. Dalton conceives that in the relative weights of the
chemical equivalents, we estimate the united weights of a determinate
number of atoms. Dr. Wollaston, moreover, did not see the utility of doing
so for an instrument of epplication to practical purposes. However, we
have learned, that since the publication of these synoptic rules, Dr. Wol-
laston has discovered that the doctrine of simple multiples (on which is
founded the atomic theory), could be applied to the construction of his loga-
rithmic scale, by simplifying all its relations ; for if we assumed for unity,
hydrogen instead of oxygen, all the results obtained till the present day
would fe to confirm the first data; but, undoubtedly, they have not
appeared sufficiently numerous to Dr. Wollaston, to induce him to gene-
ralize them. We expect, impatiently, the result of the important labour
which this learned eheinist has undertaken on this subject.—Tratté p. 205.

Surely any man acquainted with the first elements of chemistry,
who glances his eye over the scale, must see that the successive
numbers, corresponding to the names, express the atomic weights
or combining ratios of the different bodies, beginning with oxygen

-at the number 10. The French chemists, in general, have
suffered themselves to be mystified on the principles of equivalent
and multiple combination by the Essay of Berzelius, on the Theory
of Chemical Proportions ; a work which has done as much injury
to the philosophy of the subject, as his precision in analytical
research has improved its details. We recommend MM. Payen
and Chevallier to read with attention the translation of Dr. Wol-
laston’s Memoir on Chemical Equivalents, inserted by M. Descotils
in the Journal des Mines, xxxvit. 101.

Ill. Reliquie Diluviane; or, Observations on the Organic Re-
mains contained in Caves, Fissures, and Diluvial Gravel ; and
onother geological Phenomena attesting the Action of an Univer
sal Deluge. By the Rev. Wiri1am Bucktanp, B.D,,
F.R.S., §e.

TuERE are few persons in whom zeal for the progress of a parti-
cular branch of natural knowledge is united to the same extent
with capacity for the pursuit, as in Professor Buckland; he has
taken up a very interesting branch of geology, and has investigated
it with no less activity than success, and his researches have con-
ducted him, by the legitimate steps of inductive reasoning, to
some very important facts connected with the remote history of
the earth. The existence of the bones of a great variety of ani-
mals, in some cases of extinct genera, and almost always of ex-

Z2

338 Analysis of Scientific Books.

tinct species, in the superficial clay and gravel of valleys, and in
certain caverns, has long excited the attention of geologists, but
they have never been so perspicuously and popularly described
as in the work before us; nor have the phenomena which attend
their deposition, been so plausibly and philosophically accounted
for by any antecedent writer. The fact is, that Mr. Buckland has
in almost all cases judged for himself; he has personally visited
the spots he describes, perambulated the caverns, exhumated their
fossil remains, and inspected their various analogies and associa-
tions ; instead of viewing the subject through the spectacles of
books, and framing hypotheses by the fire-side, we find him busily
journeying over a great part of Europe, for the express purpose
of collecting information upon the subjects before us, and his
success has been adequate to the labour bestowed upon the in-
quiry ; for he has, in our opinion, not merely described, with
much accuracy and minuteness of detail, the various districts
which he has visited, a task in itself of no small importance and
interest ; but he has established several important facts in relation
to geological theory, upon sound, firm, and indisputable evidence.
Such are the leading features and prominent merits of Mr. Buck-
Jand’s book ; but it has other claims, which, in the capacity of re-
viewers, we think it right to notice, though they are of secondary
and inferior consideration : we allude to the variety of collateral
information scattered through its pages, connected with the habits of
the animals, and to the relief which is given to the dry details by
interspersed anecdotes and appropriate quotations ; all this renders
a work which, in the hands of a German professor, for instance,
would have proved insufferably dull and monotonous, not merely
very readable, but very interesting and entertaining, without in the
smallest degree detracting from its scientific value or literary merit.
It would seem, from the table of contents, that Mr. Buckland’s
work is intended to be divided into two parts, the first containing
an account of the localities and contents of various caves in Eng-
land and Germany, with some observations on the osseous breccize
of Gibraltar, Nice, Dalmatia, §c.; and the second embracing
“‘the evidences of an inundation, afforded by phenomena on the
earth’s surface.” In respect to the manner in which the work is
got up, we need only say, that it is published by Mr. Murray.
The cave of Kirkdale, in Yorkshire, forms, as it ought, a lead-
ing subject of the volume: the rock which it perforates is that
kind of calcareous freestone which constitutes the oolite formation,
and which, from the circumstance of the ingulphment of several
rivers that traverse the district, is probably abundant in caverns.
It was discovered in the summer of 1821, by the quarrymen
of the neighbourhood, who accidentally intersected its mouth,
which was overgrown with bushes, and closed with rubbish,
probably the debris of the softer portions of the circumjacent
strata. But this original opening has been cut away, and its pre-
sent entrance isa hole in the perpendicular face of the quarry,

Buekland’s Reliquie Diluviane. 339

which expands and contracts irregularly, from two to seven feet
in breadth, and from two to fourteen in height; the roof and floor
are composed of regular horizontal strata of limestone, but in the
interior the former is studded with stalactite, and the floor covered
with a loamy sediment, of the average depth of about one foot,
and concealing the actual floor of the cavern; the surface of this
sediment was generally smooth and level.

Above this mud, on advancing some way into the cave, the roof and
sides were found to be partially studded and cased over with a coating of
stalactite, which was most abundant in those parts where the transverse
fissures occur, but in small quantity where the rock is compact and devoid
of fissures. Thus far it resembled the stalactite of ordinary caverns ; but,
on tracing it downwards to the surface of the mud, it was there found to
turn off at right angles from the sides ofthe cave, and form above the mud a
plate, or crust, shooting across like ice on the surface of water, or cream
on a pan of milk. The thickness and quantity of this crust varied with that
found on the roof and sides, being most abundant, and covering the mud
entirely where there was much stalactite on the sides, and more scanty in
those places where the roof or sides presented but little: in many parts it
was totally wanting, both on the roof and surface of the mud and of the
subjacent floor. Great portion of this crust had been destroyed in digging
up the mud, to extract the bones, before my arrival; it still remained,
however, projecting partially in some few places along the sides ; and in
one or two, where it was very thick, it formed, when I visited the cave a
continuous bridge over the mud entirely across from one side to the other.
In the outer portion of the cave, there was originally amass of this kind,
which had been accumulated so high as to obstruct the passage, so thata
man could not enter till it had been dug away.

It deserves particular remark, that the mud and stalactite
never alternate, but that there is simply a partial deposit of the
Jatter on the floor beneath it, in which, and in the lower part of
the earthy sediment, the animal remains were chiefly found. In
the whole extent of the cave, very few large bones have been dis-
covered that are tolerably perfect; most of them are fragmented,
and some into very small pieces, cemented by stalagmite, so as to
form an osseous breccia.

In some few places, where the mud was shallow, and the heaps of teeth

and bones considerable, parts of the latter were elevated some inches
above the surface of the mud and its stalagmitic crust ; and the upper ends

of the bones thus projecting, like the legs of pigeons through a pie-crust,
into’'the void space above, have become thinly covered with stalagmitic
drippings, whilst their lower extremities haye no such incrustation, and
have simply the mud adhering to them in which they had been imbedded ;
an horizontal crust of stalagmite, about an inch thick, crosses the middle
of these bones, and retains them firmly in the position they occupied at the
bottom of the cave.

The bones already discovered in the Kirkdale cave are referable
to about twenty-three species of animals, namely, hyzna, tiger,
bear, wolf, fox, weasel; elephant, rhinoceros, hippopotamus,
horse ; ox, and three species of deer; hare, rabbit, water rat,
and mouse ; raven, pigeon, lark, a small duck, and an unknown
bird, about the size of a thrush. These were strewed all over
‘the cave, like a dog-kennel, those of the larger animals, mingled
with the rest, even in the inmost and smallest recesses; many of -
them gnawed, and the number of teeth and solid bones of the
tarsus and carpus more than twenty times as greatas could have

340 Analysis of Scientific Books.

been supplied by the individuals whose other bones are mixed
with them, From the comminuted and apparently gnawed con-
dition of the bones, Mr. Buckland remarks, that this cave was
probably, during a long succession of years, inhabited as a den by
hyzenas, and that they dragged into its recesses the other animal
bodies whose remains are found mixed with their own, a conjec-
ture much strengthened by the discovery of the solid calcareous
excrement of an animal that had fed on bones, which the keeper
of Exeter Change at once recognised as resembling the recent
feeces of the Cape hyeena. Mr. Buckland proceeds to verify this
evidence, already very conclusive, by an inquiry into the habits
of modern hyenas, of which three species only are known, and
all smaller than the fossil one; they inhabit hot climates exclu-
sively, and prow] about at night, clearing away the carcasses and
skeletons left by vultures, in preference to attacking living crea--
tures. They are so greedy of putrid flesh and bones, that they
follow armies, and dig up bodies from the grave. They inhabit
holes and chasms, are strong, fierce and voracious, and their eyes,
like those of the rat and mouse, are adapted for nocturnal vision.
To such animals the Kirkdale cave would certainly afford a con-
venient habitation, and the circumstances we find developed in it
are consistent with these habits.

We must infer from the circumstance of the bones of the hyzena
being as much broken up as those of the animals that formed their
prey, that the carcasses of the hyzenas themselves were eaten up by
the survivors ; and it is stated by Mr. Brown in his Journey to
Darfu, that when a hyena is wounded, his companions instantly
tear him to pieces and devour him. But modern hyeenas not only
devour their own species, but upon a pinch they actually eat up
parts of themselves. An old hyena in the Jardin du Roi at
Paris nibbled off his own hind feet, and the keeper of Mr. Womb-
well’s collection told Mr. Buckland that he had an hyena some
years ago which ate off his own fore paws. We, therefore, can
want no further proof of the voracity of these animals. We insert
the following passages as showing the minuteness and accuracy of
Mr. Buckland’s talent for investigation of this sort, and as bearing
upon some important collateral parts of his inquiry.

T have already stated, that the greatest number of teeth (those of the
hyena excepted) belong to the ruminating animals ; from which it is to be
inferred, that they formed the ordinary prey of the hyenas. I have, also,
to add, that very few of the teeth of these animals bear marks of age; they
seem to*have perished by a violent death in the vigour of life. With
respect to the horns of deer, that appear to have fallen off by necrosis, it is
probable that the hywnas found them thus shed, and dragged them home
for the purpose of gnawing them in their den; and, to animals so fond of
bones, the spongy interior of horns of this kind would not be unacceptable.
{ found a fragment of stag’s horn in so small a recess of the cave, that it
never could have been introduced, unless singly, and after separation from
the head : and near it was the molar tooth of an elephant. I have seen}no
remains of the horns of oxen, and perhaps there are none ; for the bony por-
tion of their interior, being of a porous spongy nature, would probably have

veen eaten by the hyzenas,—whilst the outer case, being of a similar compo-
sition to hair and hoofs, would not long have escaped total decomposition.

Buckland’s Reliqguie Diluviane. 34]

The occurrence of birds’ bones may be explained by the probability of
the hyenas finding the birds dead, and taking them home, as usual, to eat
in their den : and the fact, that four of the only six bones of birds I have
seen from Kirkdale are those of the ulna, may have arisen from the position
of the quill-feathers on it, and the small quantity of fleshy matter that
exists on the outer extremity of the wings of birds,—the former affording
an obstacle, and the latter no temptation, to the hyenas to devour them.

With respect to the bear and tiger, the remains of which are extremely
rare, and of which the teeth that have been found indicate a magnitude
equal to the great ursus spelzeus of the caves of Germany, and of the largest
Bengal tiger, it is more probable that the hyznas found their dead car-
casses, and dragged them to the den, than that they were ever joint tenants
of the same cavern. It is, however, obvious that they were all at the same
time inhabitants of antediluvian Yorkshire,

As ruminating animals form the ordinary food of beasts of prey,
it is not surprising they should abound in the Kirkdale Cave ; but
it is not so obvious by what means the bones and teeth of the ele-
phant, rhinoceros, and hippopotamus were conveyed thither.
Mr. B. suggests that these may perhaps be the remains of indivi-
duals that died a natural death ; for though a hyzena would neither
have had strength to kill a living elephant or rhinoceros, or to drag
home the entire carcass of a dead one, yet he could carry away
piecemeal, or acting conjointly with others, fragments of the most
bulky animals that died in the course of nature, and thus introduce
them to the inmost recesses of his den.

Should it be asked, why no entire skeleton has been found, we
find a reply in the habit of the hyzna to devour the bones of his
prey, and the gnawed fragmentsand album grecum afford evidence of
such propensity having been gratified, though the latter is in much
less quantity than we should have expected to find it; but from
its want of aggregation when recent it would probably have beensoon
disintegrated and trodden down, except in particular instances of
extreme constipation. The question which naturally suggests itself,
why we do not find at least the entire skeleton of the one or more
hyzenas that died last, and left no survivors to devour them, is, we
think, satisfactorily answered by our author, who ingeniously ob-
serves that the last individuals were probably destroyed by the
diluvian waters, on the rise of which they may be supposed to
have rushed out of their dens and fled for safety to the hills—that
they were extirpated by this catastrophe is shown by the discovery
of their bones in the diluvial gravel both of England and Germany.

Having thus summed up our author’s evidence in favour of the
Kirkdale Cave having been inhabited as a den by successive gene-
rations of hyenas, we shall not stop to consider the other hypo-
theses which may be suggested in reference to it; but proceed to
some considerations which it suggests. In the first place, it appears
manifest, that the accumulation of bones must have gone on
through a long succession of years, while the animals in question
were natives of this country. Secondly, the general dispersion of
similar bones through the gravel of great part of the northern
hemisphere, shows that the period in which they inhabited these re-
gions immediately preceded the formation of this gravel, and that

342 » Analysis of Scientific Books.

they perished by the same waters which produced it. Thirdly, that
the bones belonged to extinct species which have never re-esta-
‘blished themselves in the northern portions of the world. |The
phenomena of this cave, therefore, seem referable to a period im-
mediately antecedent to the last inundation of the earth, when it
was inhabited by land animals bearing a generic and often a specific
resemblance to those which now exist; and they also seem to de-
monstrate that there was a long succession of years in which the
elephant, rhinoceros, and hippopotamus had been the prey of the
hyzenas, which, like themselves, inhabited this country in a period
immediately preceding the formation of the diluvial gravel. The
catastrophe producing this gravel appears to have been the last
event that? has operated generally to modify the surface of the
earth, and. the few local and partial changes that have succeeded
it, such as the formation of torrent grayel, terraces, peat bog, ge. all
conspire to show that the period of their commencement was sub-
sequent to that at which the diluvium was formed.

But we come. now to one of the most curious parts of the very
curious subject before us, which is, that four of the genera of ani-
mals whose bones are so widely dispersed over the temperate and
polar regions of the northern hemisphere, at present exist in tro-
pical climates only, and chiefly indeed south of the equator; and
that the only country in which the elephant, rhinoceros, hippopo-
tamus, and hyzna are now associated is southern Africa. In
the neighbourhood of the Cape of Good Hope, they all live and
die together, as they probably formerly did in Britain, whilst the
hippopotamus is now confined exclusively to Africa, and the
elephant, rhinoceros, and hyzena are also diffused widely over the
continent of Asia.

As we consider it amply proved, by Mr. Buckland’s researches,
that the animals actually lived and died where their remains are
now found, and were not drifted thither by diluvian torrents, it is
pretty obvious either that the antediluvian climate of these lati-
tudes was warmer, or that the animals had a constitution adapted
to the regions of a northern winter, This last opinion derives
support from the Siberian elephant’s carcass discovered entire in the
ice of Tungusia, the skin of which was covered by remarkably
Jong hair and wool; and, in 1771, an equally remarkably hairy
rhinoceros was found in the same country. There are, moreover,
existing animals which have species adapted to the extremes both
of polar and tropical climates. Though we confess ourselves
rather inclined to adopt this view of the subject, it must be con-
fessed that many stubborn facts may be urged against it, a few of
which have been well put by Mr. Buckland, who espouses the
former opinion. Such, for instance, as the abundance of vegeta-
ble remains, as well as those of animals, which are now peculiar
to hot climates, but which abound in the secondary strata and di-
Juvium of high northern latitudes. ‘ To this argument,” continues
our author :— :

Buckland’s Religuie Dilwviane. 343

To this argument I would add a still greater objection, arising from the
difficulty of maintaining such animals as. those we are considering amid
the rigours of a polar winter ; and this difficulty cannot be solved by sup-
posing them to have migrated periodically, like the musk ox and rein-deer
of Melville Island; for, in the case of crocodiles and tortoises, extensive
emigration is almost impossible, and not less so to such an unwieldy
animal as the hippopotamus when out of water. It is equally difficult to
imagine that they could have passed their winters in lakes or rivers frozen
up with ice; and though the elephant and rhinoceros, if clothed in-wool,
may have fed themselves on branches of trees and brushwood during the
extreme severities of winter, still I see not how even these were to be
obtained in the frozen regions of Siberia, which at present produce little
more than moss and lichens, which, during great part of the year, are
buried under impenetrable ice and snow; yet it is in those regions of
extreme cold, on the utmost verge of the now habitable world, that the
bones of elephants are found occasionally, crowded in heaps, along the
shores of the icy sea from Archangel to Behring’s Straits, forming whole
islands composed of bones and mud at the mouth of the Lena, and encased
in icebergs, from which they are melted out by the solar heat of their short
summer, along the coast of Tungusia, in sufficient numbers to form an
important article of commerce.

The chronological inferences deducible from the furniture of
the Kirkdale den are summed up by Mr. Buckland at the con-
clusion ef his description of it, and are briefly as follows : 1. There
appears from the state of the sides and bottom of the caye, (be-
neath the bony aggregate,) to haye been a period in which it
existed as an untenanted and empty aperture. 2. It was inha-
bited by hyzena’s, §c.; and, as we might suppose, stalactitic and
stalagmitic formation still went on in it. | 3. Mud was intro-
duced, and the animal at the same time extirpated. 4. Stalag-
mite was again deposited, as shown by the crust upon the sur-
face of the mud, and during this period no creature seems to
have entered the cave, save and except rats, mice, rabbits, and
foxes. From the limited quantity of the latter stalactite, and
from the undecayed condition of the bones, our author argues
that the time elapsed since the deluge is not of excessive length,
that is, not exceeding six thousand years.

With the mass of minute and accurate information, derived
from his visits to the cave at Kirkdale, Mr. Buckland proceeds
to inspect several similar accumulations of bones in other parts
of England; and having satisfied himself of their general con-
cordance with the above, and of the verification which they afford
of his main deductions, he determined upon a visit to some
celebrated similar depositaries in Germany, of which the volume
before us contains the most entertaining and instructive account
extant. He shows from the history and contents of the diluvian
gravel of the Continent, that it is identical with that of our own
island; and that with respect to the bones that occur in caverns,
the chief difference seems to be, that in Germany some of the
caves have remained open, and have consequently been inha-
bited by modern or existing species. We cannot follow our
indefatigable author into the details and descriptions of the inte-
riors and contents of all these diluvian cemeteries, but the fol-
lowing remarks apply generally to them all :—

344 Analysis of Scientific Books.

With respect to the apertures themselves, whether fissures or
caverns, they appear to have been without mud or pebbles when
the animals lived and died, whose remains are now found in
them. In regard to the present mouths of these dens, our author
adduces evidence to show, that they did not exist formerly as_
at present, but that they are rather truncated portions of the
lower regions of the original caverns, laid open as it would seem
by the diluvial waters which excavated the valleys in whose
cliffs they stand, and which also drifted into these the mud and
pebbles. The diluvial matter itself Mr. Buckland describes as either
amass of pebbles, or of loam, or sand, with bones indiscriminately
distributed through them, and sometimes cemented into an osseous
breccia by stalagmitic infiltrations ; in short, there is a complete
analogy between the caves of Germany and of England, not merely
in respect to their earthy and osseous deposits, but in the species
of the animals whose remains are enveloped in them.

The osseous breccia of Gibraltar, Nice, Dalmatia, §c., comes
next under our author’s observation, and is ascribed to the
same antediluvian period, with the exception of certain more
recent deposits, of which some of our English caves and fissures
also furnish instances, and which are ascribed to animals that
have more lately fallen into them; when, however, the mouths
of the fissures are closed, no such recent reliquize occur, and all
is of a more ancient date,

The subject of human fossil remains is one of peculiar interest
to the geologist, and particularly so in relation to the destruction
of the human race by the deluge. But no human remains have
yet been found associated with any of the unequivocal ante-
diluvian inhabitants of the earth. Human bones, and even urns
have been discovered in the caves of Gailenreuth and Zahnloch.
In England, too, many human skeletons have been found in
caverns, but always attended by circumstances which announce
them of postdiluvian origin. Our author examined the remains
of human bodies in the cave of Wokey Hole near Wells, and
the following are his remarks upon them :

They have been broken by repeated digging to small pieces ; but the
presence of numerous teeth establishes the fact that they are human.
These teeth and fragments are dispersed through reddish mud and clay,
and some of them united with it by stalagmite into a firm osseous breccia.
Among the loose bones I found a small piece of a coarse sepulchral urn.
The spot on which they lie is within reach of the highest floods of the
adjacent river ; and the mud in which they are buried is evidently fluvia-
tile, and not diluvian; so also is great part, if not the whole, of the
mud and sand in the adjacent large caverns, the bottoms of all which are
filled with water to the height of many feet, by occasional land-floods,
which must long agu have undermined and removed any diluvial deposits
that may have originally been left in them. I could find no pebbles, nor
traces of any other than the human bones, on the single spot 4 have just
described ; these are very old, but not antediluvian. In another cave on
this same flank of the Mendips, at Compton Bishop, near Axbridge.
Mr. Peter Fry, of Axbridge, discovered, in the year 1820, a number o
bones of foxes, all lying by coal in the same spot, and brought away
fifteen skulls. These, also, like the remains of foxes in Duncombe Park
and near Paviland, are of postdiluvian origin, and were probably derived

Buckland’s Reliquie Diluviane. 345

from animals that retired to die there, as the antediluvian bears did in the
caves of Germany.

In the neighbourhood of Swansea a number of human bones
have also been found in a fissure of the limestone-rock ; these
are apparently the remains of bodies thrown in after a battle, and
are not associated with any more ancient bones, or any appear-
ances which connect them with antediluvian relics.

These and other instances of the existence of human bones,
lead us to refer them to periods subsequent to those of the
unequivocal diluvial deposits; indeed, the great abundance of
the remains of wild animals in the latter lead us to believe that
the countries could not have been inhabited by man; but that,
on the contrary, the beasts must then have enjoyed sole dominion,
Upon this subject our author agrees in opinion with Mr. Weaver.

That the satisfactory solution of the general problem, as far as it relates
to man, is probably to be sought more particularly in the Asiatic regions,
the cradle of the human race; and that another interesting branch of
inquiry connected with it is, whether any fossil remains of elephant, rhino-
ceros, hippopotamus, and hyzna, exist in the diluvium of tropical climates 5
and if they do, whether they agree with the recent species of these genera,
or with those extinct species, whose remains are dispersed so largely over
the temperate and frigid zones of the northern hemisphere.

Having thus illustrated his account of Kirkdale, and of the
caves in England, by a comparative view of similar caverns and
fissures on the Continent, our author proceeds in the second part
of his book, to consider the evidence of diluvial action afforded by
the accumulation on the earth’s surface of loam and gravel, con-
taining the remains of the same species of animals that we find in
the caves and fissures, and by the form ‘and structure of hills and
valleys in all parts of the world. Of these remains, the bones of
the fossil elephant are the most remarkable from their general
and abundant dispersion ; it differs from all living species of that
genus, but approaches more closely to the Asiatic than to that
of Africa; and, if we may judge from the Siberian specimen
already adverted to, it was clothed with a coarse reddish wool,
interspersed with stiff black hair, forming a long mane on its
neck and back, and was at least 16 feet high.

It was to be expected that the remains of this gigantic animal
should be found in the diluvial gravel of Yorkshire, from the fact
already established, that these animals inhabited the neighbourhood
of Kirkdale, whilst its caverns were occupied by the hyena; and
accordingly tusks and bones of elephants of enormous size have
been found in the diluvium at Robin Hood’s Bay, near Whitby ;
at Scarborough, Bridlington, and several other places along the
shore of Holderness. Proceeding southwards we also find them in
the interior of Suffolk, Norfolk, and Essex ; and at Walton, near
Harwich they are extremely abundant, blended with other dilu-
vial bones. In the valley of the Thames they have been discovered
at Sheppy, the Isle of Dogs, Lewisham, London, Brentford, Kew,
Wallingford, Dorchester, Abingdon, and Oxford. On the south

346 Analysis of Scientific Books.

coast of England they occur at Lyme and Charmouth, and they
have been found in the central counties. In North Wales, Scot-
land, and Ireland, these relics have also been met with always in
the superficial gravel or loam, and never imbedded in what ma
be called the regular strata.

The circumstances that attend some of these deposits require to he more
particularly detailed. In the streets of London, the teeth and bones are
often found, in digging foundations and sewers, in the gravel e. g., ele-

hants’ teeth have been found under twelve feet of gravel in Gray’s-Inn

ane; and lately, at thirty feet deep, in digging the grand sewer, near
Charles Street, on the east of Waterloo Place. At Kingsland, near
Hoxton, in 1806, an entire elephant’s skull was discovered, containing two
tusks of enormous length, as well as the grinding-teeth: they have, also,
been frequently found at iford, on the road from London to Harwich; and,
indeed, in almost all the gravel-pits round London. The teeth are of all
sizes, from the milk-teeth to those of the largest and most perfect growth ;
and some of them show all the intermediate and peculiar stages of change
to which the teeth of modern elephants are subject. In the gravel-pits at
Oxford and Abingdon, teeth and tusks, and various bones of the elepbant,
are found mixed with the bones of rhinoceros, horse, ox, hog, and several
species of deer, often crowded together in the same pit, and seldom rolled
op maniet at the edges, although they have not been found united in entire
skeletons.

For foreign localities of the fossil elephant our author refers to
Cuvier’s account of places in which they have been found all over
Europe. Of these one of the most remarkable is in the valley of
the Arno, near Florence, where they occur associated with parts
of the skeletons of hippopotami rhinoceri, hyenas, bears, tigers,
wolves, §c. In Asiatic Russia, from the Don to the extremity of
the promontory of Tchutchis, there is not a river, in the banks of
which they do not find.elephants and other animals now strangers

to that climate.

In treating of the evidence of the diluvial action afforded by
deposits of loam and gravel, Professor Buckland very justly re-
marks, that the theories suggested to account for such appearances,
have been defective from their attempting to refer to one circum-
stance two distinct classes of phenomena; namely, the general
dispersion of gravel and loam over hills and elevated plains as well
as valleys; and the partial collection of gravel at the foot of
torrents, and of mud along the course and at the mouths of rivers.
The former of these only appears to be the effect of an universal
and transient deluge, whilst the latter are distinctly referable
to the action of existing causes.

I have seen a good example of these two deposits in Holland in imme-
diate contact with one another. The alluvial detritus of modern rivers,
which is so enormous in that country, never rises above the level of the
highest possible land-floods ; but beneath this level forms nearly the entire
surface of that low and extensive flat; whilst the diluvial deposits rise
from beneath it into a chain of hills, composed of gravel, sand, and loam,
which cross Guelderland, between the Yssel and the Rhine, from the south-
east border of the Zuyder Zee, to Arnheim, and Nymeren, and form at
the latter place a cliff, overhanging the left bank of the Waal, and another
cliff of the same kind on the right bank of the Rhine, from Arnheim to
Amerongen, on the road to Utrecht. In the districts that lie below the

flood-level of these rivers, it is probable that there is an extensive deposit
of this same diluvium buried beneath the alluvium, which forms the sur-

Buckland’s Reliquie Diluviane. 347

face ; and the certainty of this fact has been established in several places,
where, from the bursting of dykes, the water has made excavations
through the alluvium into the subjacent diluviam, and washed up form it
the teeth and bones of the extinct elephant and other animals, which are
peculiar to that formation.

We are sorry that we have neither space nor time for more ex-
tended quotations from this part of the work before us, which,
though less captivating to the general reader than the history of
the dens and their inhabitants, is, in a geological point of view, re-
plete with important and essential data; and as we discover among
the pebbles that constitute this diluvial gravel not merely the
wreck of the adjacent inland districts, but also large blocks of
primitive and transition rocks which do not occur in England,
and which can only be accounted for by supposing them to have
been drifted from the nearest continental strata of Norway, we
must admit that a diluvial current from the north is the only
adequate cause that can be proposed, and that satisfies the con-
ditions of the problem.

In reference to this subject Mr. Buckland has given a summary
of facts selected from various authorities, and from his own exten-
sive observations, which tend satisfactorily to explain the great
transportation of materials from one district to another at the period
of the deluge, and which also elucidate the excavation of valleys,
and develope the general causes of those minor irregularities which
are engraved upon the earth’s surface. The general shape of hills
and valleys; the immense deposits of gravel and boulders, evi-
dently immoveable by any streams now existing; the nature of
these rounded fragments; the condition of the organic remains
that accompany them, and the analogous occurrence of similar
phenomena in all regions of the world hitherto investigated, are
such decided and convincing proofs of the universality of the dilu-
vial inundation, as must, independent of any other evidence, over-
rule all objections and difficulties connected with this very im-
portant subject. That there are difficulties to be removed, dis-
cordances to be cleared up, and doubts to be obviated, Mr. Buck-
land does not pretend to deny; but it is probable that these will,
at length, be removed by the extension of observations, physical
and geological, conducted upon the plan so ably laid down and
successfully pursued in the work before us.

In conclusion, we shall only remind our author of the excellent
advice and instructive observations of the President of the Royal
Society, on presenting him with the Copley medal for his original
description of the cave at Kirkdale, printed in the Philosophical
Transactions for the year 1822. On that occasion Sir H. Davy
took a luminous view of the importance and bearings of such re-
searches, and suggested, in terms at once explicit and eloquent,
the line of inquiry most likely to promote and perfect them; and
the honours, thus conferred by the Royal Society, seem not to have
been scattered upon barren ground, for to them we apparently owe

348 Analysis of Scientific Books.

thé extended and minute description of the caves in Germany,
contained in the present volume and the undiminished zeal with
which Mr. Buckland is, as we are informed, at present pursuing
his geological investigations.

To the Editor of the Journal of Science, 5c.

Sir, ‘

The candour and liberality by which your excellent Journal is so honour-
ably distinguished, lead me to hope that you will admit a few observations,
intended to remove an impression to the disadvantage of a highly respect-
able character.

In the review of ‘“‘ A Comparative Estimate of the Mineral and Mosaical
Geologies,” by Granville Penn, Esq., No. 29, page 112, is the following
passage: “‘ De Luc would not use the term created, ‘ because,’ said he, ‘ in
physics 1 ought not to employ expressions which are not thoroughly under-
stood between men.” Our author reprobates his conduct and his argument
with just severity : “‘ Was he aware,” says Mr. Penn, “ that in excluding
the word, he at the same time excluded the idea associated with the word,
and acer with the idea, the principle involved in that idea; the exclu-
sion of which is the very parent cause of all materialism and all atheism.”
The reader of this paragraph, if unacquainted with the writings and the
character of Mr, De Luc, will certainly suppose that he did not believe, or
at least thought it unphilosophical to acknowledge, that “ in the beginning
God created the heavens and the earth;” and the memory of one of the
best and most pious of men may be injured by those who are ably defend-
ing the same cause which it was the business of his life, and the object of
all his writings, to advocate, In the introductory chapter to “ L’Histoire
de la Terre et de ’Homme,” Vol.1, page 22, he says: ‘‘ Je declare des
Ventrée, que la consequence immediate de toute la partie physique de cet
ouvrage est, que la Genése, le premier de nos liyres sacrées, renferme la
vrai histoire du monde ; c’est a dire, que l’étude de la terre nous en montre
les plus grands traits, et n’en contredit aucun.”

Page 50. ‘¢ Je suis convaincu dela certitude de la revelation et j’ap-
porte ma petite contribution dans ses moyens de défense,”—‘ J’entrepris
d’observer le monde moral et physique ; je Jus ce qu’en disoient les philoso-
phes, et bient6t je soupconnai que ceux qui abandonnoient Moyse yoyoient
mal on raisonnoient sans examen.”

After having, with the assistance of his brother, devoted thirty years to
actual obseryation of the present state of the earth, Mr. De Luc says:
% Lorsque nous fumes persuadés, par l’étude des phenoménes, que le recit
de Moyse sur Vhistoire de notre globe etoit le seul systéme vrai, nous for-
mames le dessein d’en instruire ceux qui ne recherchent pas.”—Vol. 5.
page 759. .

The whole intention of De Luc’s writings, during the course of a long life,
is to confirm the Mosaic account of the creation and the deluge by accurate
investigation of the present state of the globe. His system, with regard to
the Deluge, is the same as that of Mr. Penn in his ‘‘ Comparative Esti-
mate, &c.;” and I believe that very able work would have met with his
warm approbation. The only circumstance in which De Luc may appear to
depart from the literal sense of the first chapter of Genesis, is with regard
to the Loneee of the period there called a day. . Whether he was right or
wrong in his ideas on that subject I do not presume to decide, but he cer-
tainly had no intention io deviate from the meaning of Moses, for every part
of his work is written to support the authority of Scripture. Those who
will take the trouble to look into his fifth volume, page 630, will find a clear
account of his sentiments, which { should injure by attempting to curtail it.
I could prove what I have here asserted from almost every page of his
numerous publications, and particularly from his Letters to M. Le Tellier ;
but 1 will only beg leave to call your attention to the passage which you
say Mr. Penn “ reprobates with just severity.” According to this gentle-
man’s translation, De Luc says: ‘ I shall not say created, because in phy-
sics I ought not to employ pxprenaina which are not thoroughly understood
between men.” The original is givenina note, and the words are, “ Je

Letter to the Editor. 349

ne dirai pas qu’elles ont été créés ainsi, parce-qu’en physique je ne dois pas
player des expressions sur lesquelles on ne s’entend pas.”—Tom. 2. page
211. I request any person acquainted with the French language to com-
a the original with the translation, and they will see that the author

as been misunderstood, and that his meaning is as follows: “ I will
not say that they have been created thus,” (in their present state,) “ be-
cause in physics I must not employ expressions on the sense of which
people are not agreed.” The whole passage runs thus. After describing
two classes of mountains, he says of the second, “ On les a nommées
secondaires, et les autres primitives. J’adopterai la premiére de ces ex-
pressions, car c’est la méme qui nous étoit venue al’esprit, a mon frére
et a moi, longtems avant que nous l’eussions vue employer 5 mais je
substituerai celle de primordiales, 4 primitive, pour l'autre classe de
montagnes, afin de ne rien décider sur leur origine. Il est des mon-
tagnes dont jusqu’a présent on n’a pu déméler la cause; voila le fait.
Je ne dirai dont pas qu’elle ont été créés ainsi, parce qu’en physique je
ne dois pas employer des expressions sur lesquelles on ne s’entend pas.
Sans doute cependant, que histoire naturelle, ni Ja physique, ne ‘nous
conduisent nullement a croire que notre globe ait existe de toute éternité,
et Jorsqu’il prit naissance il fallut bien que la matiére qui la composa fut
de quelque nature, on sous quelque premiere forme integrante. Rien donc
n’empeche d’admettre que ces montagnes, qne je nommerai primordiales
ne soyent réellement primitives ; je penche méme pour cette opinion.”—
Without pretending to any skill in geology, 1 appeal to the common sense
of any person who can read and understand this quotation ; and I ask whe-
ther the writer can be suspected of wishing to exclude the idea of creation?

ifI oe rye myself with warmth on this subject, I beg that I may not be
supposed to speak with disrespect of Mr. Penn’s admirable work, or to
suspect the excellent author of intentional misrepresentation of a fellow-la-
bourer in the same cause ; but the character of a friend, whom I have _re-
spected and esteemed for more than forty years, is sacred in my eyes. Mr.

e Luc was one of the best men and best christians that I have ever
known, and I knew him well. Our late excellent king and queen honoured
him with their esteem and confidence. Her majesty was his pupil during
many years, and she would not have received instruction from a person
whom she did not believe to be a safe guide on the important subjects of
his lectures. He was sent by the king to Germany, to inquire into
the state of religion there, and particularly into the views of the
Illuminati, whose dangerous principles were first developed by him. It was
De Luc who ventured to caution his royal master against the plausible, but
dangerous, system of education, which it has since been found expedient to
counteract, by establishing the national schools. On every occasion, M.
De Luc was the active and indefatigable supporter of our constitution in
church and state. His talents were always exerted in the cause of religion
and morality, and his life exemplified every virtue which his writings are
designed to inculcate. There may be mistakes in some parts of his system,
but those who knew the man, as [ had the happiness of knowing him, may
venture to answer for the intentions of the author; of whom his opponent
M. Le Tellier, thus expresses his opinion: “‘ Je vous réspecte comme gran
Geologue, et comme ami et defenseur zélé du Christianisme.”

We do not hesitate a moment to give the preceding communication, word
for word, as we received it; and we are equally ready to express our full
conviction that De Luc’s intentions were as right-minded as our valued cor-
respondent represents them to have been. e are not, however, so fully
convinced, that, in the passage which has called for the preceding ani-
madversions, he is not reprobated “‘ with just severity.” That Mr. Penn
has not misunderstood it, for want of a sufficient knowledge of French,
may be pretty confidently assumed by any one who has read his “‘ Compa-
rative Estimate,” than which, we have met with very few works that evince
a more perfect acquaintance both with modern and dead languages. Has
he misrepresented it, then? We think not.—What can “ des expressions”
refer to, but the word créés, with or without its ainsi, as you please? Itis
the only word in the sentence about which an pray abi sre can b
possibility exist. Had De Luc written, Je nc Peet sy quwiils ont été yee 4
ainsi, would he have thought it necessary to give his reason for declining
the phrase ? The question is, were the mountains originally formed as they

350 Analysis of Scientific Books.

now are, créés ainsi? or are they the result of a chymical crystallization from
a chaos, or heaven knows what? De Luc would not undertake to say they
were created thus, because it is an expression about which men are not
agreed; that is, men are not agreed as to what is, and what is not, a
creation, and therefore he declined to use the term. But whether Mr
Penn (and we with him) has or has not misunderstood De Luc, we are
sure that he has not intentionally done him injustice, (as indeed our cor-
respondent admits ;) and that the severity with which he felt it necessary
in several instances, to comment on his writings, was painful to his own
feelings. Witness the following passages, which we sheuld haye quoted in
our late review of the ‘‘ Comparative Estimate,” had our space admitted
of it. After another equally severe, and, in our opinion, equally just cen-
sure of De Luc’s “ daring and inerudite tampering with texts of Scripture,”
by which he interprets the six days of creation not to be “ days of twenty-
four hours, but periods of undetermined length,” Mr. Penn adds, “It is
not without sincere pain that I feel myself compelled thus strongly to
censure this particular work * of the able and amiable De Luc; but in so
sacred a cause, there may be no complimentary reservation from man to
man. He has himself rendered it indispensably necessary that a strong
and effectual caution should accompany his writings ; because they tend
to dissolve the foundations of the edifice, which they officiously offer to
secure. They are calculated, therefore, to produce an evil which no hos-
tile assault could effect ; for they are calculated to attract a confidence,
which an hostile demonstration would repel. De Luc designed friendship ;
but, unfortunately, the execution of his friendly design is real hostility.
He was eminently distinguished, and his memory is deservedly honoured,
in the department of physics ; he was great, also, in shewing the concord
of many natural phoenomena with the Mosaic record of the Deluge; but
there was the limit of his true geology. As soon as he attempted to pro-
ceed farther, and to argue the mode of the first formation of this globe, his
mind lost its guide; he strayed ultra crepidam; and he brought himself
into the same predicament with those whom he had before refuted and con-
demned in the article of the Deluge. The measures of time which he had phi-
losophically denied to them, he now unphilosophically and inconsistently
demanded for himself ; they could not explain the revolution of this earthly
system, without the aid of exorbitant measures of time which the Mosaical
record refused them; and he himself could not understand the Mosaical de-
scription of the creation of this system, without exacting measures equally
exorbitant, and equally refused by the record.”—P. 208. “The general
discernment and assertion of the great fact of the Deluge, was the bright
point in his ‘De Luc’s) geology. So long as his view was confined to the
contemplation and exposition of that fact, his mind was collected and
concentred+. When he quitted it, to put himself in search of the mode
by which secondary causes produce first formations, it became perplexed
and bewildered +. So long as he confined bimself to the defence of that
strong part, he evinced great skill, conduct, and resolution.”—P. 273.
“ Thus much it has been indispensably necessary to expose as a cau-
tionary distinction, and to insist upon, relative to this well-intentioned
but dangerous instructor, lest his:success in the one argument should become
a snare to draw his readers into his own failure in the other.’—P.. 274,
We.could quote many other passages in point, but it is unnecessary, We
highly respect the feelings that have induced our correspondent to stand
forward in defence of a man, at once eminent as a philosopher, and en-
deared by a long and ardent friendship. If we have joined with Mr.
Penn in censuring some of his opinions, it is because we feel with hira, that
in so sacred a cause there may be “no complimentary reservation from man
to man:” if those we entertain militate against the opinions of some other
persons whom we highly honour, we may lament the discrepancy ; but the
same feeling forbids us to surrender our judgment, till convinced that it is
erroneous. The sentiments we lately expressed, of Mr. Penn’s “ Compa-
rative Estimate,” we still retain, and shall continue to retain them till we
see his arguments refuted by abler arguments, and his hypothesis subverted
by one more consistent, hysically and morally, with established facts, and .

the sacred record of the Bible.

* Lettres Géologiques.
+ Lettres sur UVHistoire de la Terre. ] Lettres Geologiques.

351

Art. XIII. ASTRONOMICAL AND NAUTICAL
COLLECTIONS.
No. XIV.
i. The Resistance of the Air, determined from Captain KateEr’s
Experiments on the Pendulum.

Tue effect of resistances of various kinds on the vibrations of
the pendulum is become a subject of increased importance.
from its influence on the determination of a standard measure:
for although the effect of these resistances on the time may be
wholly inconsiderable, it is by no means superfluous to prove,
by demonstrative evidence, that they are actually insensible.

A constant resistance, and a resistance proportional to
the square of the velocity, produce either no change at
all of the time of vibration, or an infinitely small change
when the arc is infinitely small: but a resistance simply pro-
portional to the velocity, if it be at all considerable, may pro-
duce a sensible retardation, even in an evanescent are. It
becomes, therefore, of some importance to inquire, what is the
law of the resistance to very slow motions ; and the elaborate
experiments of the indefatigable Captain Kater will afford us
the information that is required for establishing, in this respect,
the sufficiency of the superstructure that has been built on them,
It is, however, necessary, to take the mean of a large number
of separate registers of observations, in order to investigate the
laws of the retardation : for the question is so delicate, that the
results of any small number of experiments might lead to very
erroneous conclusions: but when properly analysed, the expe-
riments, related in the third part of the Phzlosophical Transac-
tions for. 1819, are amply sufficient to show that a certain por-
tion of the resistance to the motion varies simply as the velo-
city; and that it cannot be correctly expressed, as Mr,
Gilbert has supposed, by a constant term and a term
proportional to the square of the velocity only. Sir Isaac
Newton, indeed, has hinted in the Principia, that a constant
term, expressing the resistance derived from the thread suspend-
ing his pendulum, with another term proportional to the square

Vou. XV. 2A

352 Astronomical and Nautical Collections.

of the velocity, might be sufficiently accurate for the purpose :
and Euler has inferred, from Newton’s experiments, that the
constant resistance of the air to the motion of a leaden ball,
two inches in diameter, was about one millionth part of its
weight, or that it would cause it to remain at rest at an angu-
lar deviation of 0.2 from the vertical line: but a part at least
of this resistance may perhaps have been derived from the want
of flexibility or elasticity of the thread.

From a mean of 60 experiments of Captain Kater, consisting
of about 5000 vibrations each, we obtain 1.°185, 19.086, 0°.997,
0°.919, and 0°.843 for the successive values of the ares, at
intervals of about 960 vibrations: and a slight irregularity in
the second differences of these numbers makes it probable that
.997 ought to be altered to .998. With this correction, the
successive diminutions, in about 1920 vibrations, will be .187,
.167, and .154, for the respective arcs of intermediate values,
each of which must be supposed to exceed the intermediate are
actually observed by one third of its deficiency below the mean
of the two neighbouring numbers, and we may call them 1.088,
1.000, and .9195, respectively.

Putting then D = x + Ay + A%z, for the diminution of the
arc, we have three equations, the last of which, subtracted from
the first, gives us .1685 (y + 2.1075 z) = .033, and
y + 2.1075 z = .1958; consequently, if z = 0, y = .196,
which would be the coefficient for a resistance simply propor-
tional to the arc, giving x + .196 for the amount of the second
diminution, that is, .167; so that x would require to be negative,
which is impossible: and if y = 0, z = .093, and the second
diminution would require x to be .074: a value which is sufh-
ciently compatible with these equations, but which would not
be applicable to the shorter vibrations; an are of 0.°80, for
example, exhibiting a diminution of about .11, and leaving only
about .050 for x, so that x must probably be still smaller than
.05, and if we make it = .040, we shall have .127 left for y+z,
and .196 — .127 = .069 = 1.1075 z, and z = .062, and
y = .065, and D = .040 + .065A + .062 A*, which gives
.132 for an arc of .8,and 2 is still too large. Now, if we take

Astronomical and Nautical Collections. 353

x somewhat smaller, we shall reduce the expression to a per-
fect square, and we shall find that (.16 4 .25 A)’ = .0256 +
080 A + .0625 A? will represent the diminution with great
accuracy, giving .187, .168, and .152, for the respective arcs of
1.09, 1.00, and .92: and this expression has the advantage of
affording a very easy integration for the arc.

For, if ¢ be the number of vibrations divided by 1920, we have

— dA =(.16 + .25A)? dé, and - dA. ae: but
(16 + .25A)?
et oR et er SE i ag t + cor
16 + 25A (.16+25A)? 16 + .25A
.16 + 25A= * ,and 64+ A= 16 : whence, put-
t+c t+ec
ting .64 + A = B, andits initial value 6,6 = 16 ora
c )
consequently B = is , and e ee oni + Ly
a0 b 16

b
In many of the series of experiments, it is necessary to make
some yariation in the constant coefficients, on account of the
state of the atmosphere, and we may take in general B= A +

and = = 7 + — the factor q,in thecase already computed,
9

being made either 16, or 16 x 1920, aceordingly as we wish to
take the interval of the coincidences for the unit of time, or to
express it in seconds; and C, in some of the series of experi-
ments, appearing to be about 1° or even 2°, instead of 0°.64.

The supposition of © =. 1° is equivalent to that of D= .04.+
.04A +4. .01 A’,g becoming in this case- 25.4 instead of 16.

The constant part of D, SES by 2, causes in half a vibra

tion a retardation of _— xz — 0°.000067 = 0'.004 = 0". 24,

seks happens to agree singularly well with the 0.20 deduced
by Euler from Newton’s experiments.
We may easily compute, from the value of A thus Setctaidieds
the total retardation depending on the vibration in’ a circular
2A2

354 Astronomical and Nautical Collections.

curve, which is expressed, for a small arc of vibration, by one-
eighth of the verse sine, the whole time of the vibration being
unity, or, for the arc A, since the verse sine of 1° is .000152, by
very nearly .000019 A; and the fluxion of the time being df,
that of the circular excess will be as A’dt = (B — C)dt =

C2 dt — 2BC dt + Bedt: now we =1+ tor = 14 pt,
q

: b 1 dt 1

uttin = —,and B = 6 ha Gee eee ay 9 Ve

Se See 1 + pt Jr P

hl (1 + pé), consequently the fluent of the second term is

~ 20 2 na + pd) = — 2Cqhl = that of the third, or
P

Ng OB se ay. being, when corrected, Bb Pio pe Be

(1 + pt)? po TL pt th ae
B

= 0b — = bBt; so that the whole circular excess will be-

come .000019¢ (C? — 2C ane (1 + pt) + a ) or
pt 1 + pt

000019¢ (— .41 — 1.28 nee 4+ BB) = .00001 (1.98B

— 2.432 Init + .779.) Taking for example, Captain

Kater’s first register of experiments, in which a = 19.38, and

5 b seb A0 pe
x t a that — b = 1.2949 =
A .92, when ¢ was ao S0rthat heme 55
b 5.05 5.05
14+ 7é = 1+ 5£; we must heremakeg = ——_ =
q q q .2949

17.124, and L 6.850, and hl. being = 703] — .4447 =

.2584, the whole is .00001 (5.987 — 4.304 + .779)t=
00002462, or 2.12 in 86050 vibrations; which agrees exactly
with Captain Kater’s computation from the separate arcs ob-
served,

If we adopted the Newtonian hypothesis of a resistance mea-

Astronomical and Nautical Collections. 355

—dA

%

sured by m + n A®, we should have = dt,andé=
m

= VE _. are tang( Ay — A), consequently ,/ (mn) ¢= — are

tang ( /— A), and tang ,/(mn)t, = — J/=A and A =

— * tang (4/ (mn) ¢) + c; and, for the correction of the
nr

fluent, a = + c, andA=a— J — tang. (4/ (mn)t).
n

There appears to be an oversight in a remark inserted among
the Elementary Illustrations of the Celestial Mechanics, p. 145;
where it is observed that “the whole time of the oscillation can
never be sensibly affected by any small resistance proportional
to the velocity ;” for, in fact, the coefficient y, in the expression

mm.

of Laplace, being equal to f/f (k— eo is in some degree

affected by m, which expresses the resistance ; and the time is
affected by y, though Laplace has not investigated the precise
effects of a given resistance. That which is here inferred from
Captain Kater’s experiments, however, would scarcely produce
a retardation of one fiftieth of a second in a year: and must,
therefore, be wholly neglected.

If we are anxious to reconcile the existence of a retardation
proportional to the velocity, with the common theory of the im-~
pulse of fluids, it will not be difficult to understand how the
one may possibly be derived from the other. We have only to
suppose the pendulum subjected to the influence of a very slow
current of air, in order to deduce a resistance nearly proportional
to the velocity v from another, which depends on (c v)?. For
it will appear, by considering the directions of the forces con-
cerned, that at the extremities of the vibration, while the velo-
city of the current exceeds that of the pendulum, and ¢ — v
remains positive, the quantity 2cv will denote a retarding force
throughout the motion, and that the portions c2 and v? will be
retarding in one direction and accelerating in the other, and
will haye no sensible effect on the extent of the vibrations ;

356 Astronomical and Nation! Collections.

while, on ‘the other hand, if the velocity of the pendulum to-
wards the middle of the vibration exceeds that of the current,
the force 2cv will retard the motion in one direction, and acce-
lerate it in the other, leaving only the constant resistance c?, and
the variable quantity v2, which is proportional to the square of
the velocity. We obtain, therefore, for the extremities of the
vibrations, a force proportional to the simple velocity, and for
the middle, a constant resistance, and another force vatying
simply as the velocity, the joint effect of all which must be a
resistance nearly such as has been inferred from Captain Kater’s
experiments, if the current moved at the rate of about half an
inch in a second, which would have been scarcely perceptible
to the senses.

The question, however, regards not so much the distribution
of the resistance through the different parts of a single vibra-
tion, as its comparative value for the mean velocities of the sue-
cessive vibrations. Now, if the velocity of the current always
exceeds that of the pendulum, the only effective resistance will
be proportional to the simple velocity ; and when it is smaller
‘than the greatest velocity of the pendulum, the resistance will
approach more and more to the ratio of the square of the velo-
cities increased by a constant quantity; and supposing the
velocity of the current to remain small and nearly uniform,
while the arc of vibration considerably diminishes, the whole
resistance will at first be more nearly as the square of the are,
and if the are be sufficiently diminished, the resistance propor-
tional to the simple velocity will at last remain alone. Hence,
it is easy to understand the variation of the constant coeffi-
cients in the different series of Captain Kater’s experiments.

12 April, 1823.

ii. Extract from a Letter to Professor ScnumacuEn, relating
to BessEt’s Refractions.

1 do not quarrel with you for your confidence in Bessel: but
I think you have not sufficiently attended to the limitation
under which he himself originally published his Theory of Re-
fraction, ‘Fundam. p. 55< “In distantiis a vertice non super

Astronomical and Nautical Collections. LAY

antibus 86°, tabule mew, ut docet allata comparatio, prorsus
cum observationibus Bradleianis congruunt.” And, in fact, the
mean errors, as deduced from his own computations, p. 53, are
these :

} ’ “
Zenith Distance 89 28 Error -+ 37.0

88 40. + 10.7
88 13 + 11.1
87 34 + 4.0
87 24 + 2.7
CY ROFEE + 4.7

We may also consider Mr. Delambre’s authority as amply
sufficient for the refraction at the horizon, which he makes
33’ 46”.3, from several hundred observations, made at Bourges,
from 70° to 90° 20’ zenith distance. Now Bessel’s table gives,
for the horizon, about 36’ 30” ; that is, 2’ 44” too much.

It may be said that these errors afford no practical objection
to the table, because observations are very rarely made at such
altitudes : but surely they are objectionable in a theoretical point
of view, since it is only the extreme cases that afford any test
of the truth of the theory: for in common cases, all theories
agree sufficiently well; and in fact, Mr. Bessel’s supposition,
that the density is so related to the height s as to be expressed
by e~"“, is contrary to all experience with respect to the distri-
bution of temperature in the atmosphere.

I have to thank you for your Auxiliary Tables for 1823; but
I must enter my formal protest against the decided manner in
which you mention the differences between the declinations of
Greenwich and of Konigsberg.

! * & *
ili. Specimen of Mr. SrocKiER’s Inverse Method of Limits. In
a Letter to CHanLes BawBaceE, Esq., F.R.S.
Dear Sir,

I have received from Mr. Stockler the manuscript of a work
in Portuguese, dedicated to the Royal Society, and entitled
Methodo Inverso dos Limites. 1 do not know that there is any
immediate probability of its being made public: but I wish to
ask your opinion of the degree of utility that is to be expected

358 Astronomical and Nautical Collections.

from these investigations, as far as you can judge from the
specimen which I send you, containing what the author con-
siders as the fundamental proposition of his method ; a method
of which the object can only be, as he observes, ‘‘ to determine
the law or the form common to all the series of which a given
function can be the limit of expression; and which is therefore
reducible to the solution of this single

PROBLEM.

Supposing x to be any function of any number of variable
quantities, and representing by Fx any function of 2, and con-
sequently of the same variable quantities that enter into the ex-
pression of x; to determine the form, or the general law, com-
mon to all the series of which Fx can be the limit of expression.

SOLUTION.

Taking any state whatever of the magnitude of x to serve as
a term or limit, to which all the others may be referred, we
shall designate it by the name of the Primitive State, and all
the others by the denomination of varied or derivative states.
Then representing by x the primitive state of the quantity or
function indicated by x, and any of its derivative states by
x + u, we shall have Fx for the primitive state of the function
of x indicated by the characteristic F, or the magnitude of Fx
corresponding to the primitive state of the function represented
by x, and F (# + zw) will represent the magnitude of Fz cor-
responding to z + u. Now, as the increment u is absolutely
arbitrary, we may consider it as capable of admitting states of
magnitude less than any other that may be assigned: and,
therefore wis a variable without any limit to its diminution;
whence it follows that 2 = lim (@ + ~); and Fr = lim
F (c+u). It may, consequently, be inferred that F(«-+-u) must
be equivalent to Fx more or less a function of x and u, or of u
only; without limit to its diminution; so that, considering the
“most general form of F (# + u) after its separation into two
parts, we shall have

F (¢ + u) = Fe + VF’ (a,x)

V being a function of w without limit to its diminution, an

Astronomical and Nautical Collections. 359

F’ (a,u) a function of’ and x capable of limitation. For the
same reason, keeping always in view the most general form of
the functions of « and u, we must have
F(aup= FP ake Foy),
F" (uv) = FY 24 V" F" (2,u):
F" (xu) = FY ao + VW" FE” (xu), &e.
V'; V”, &c., being functions of w without limit in diminution,
and F” (a,u) ; F’” (au); &c., functions of x and w capable of
limitation. Now the first of these conditions cannot be ex-
pressed in a more general manner, than by making
Ve io ou.
VAvssnasgiu.
Vv’ = uo" u, &e.
expressions in which gu; 9'u; 9”u, &c., represent functions of
u capable of limits, or constant quantities : and the substitution
of these values, in the former equations, reduce them to
F (atu) =F «c+ugpuF’ (2,u).
FY (2,u).. SF ete". FS (au);
F’ (au), = Foe + ug’ a F" (2,u); &e.
and the substitution of each of these in the others gives us
finally,
F(a+u) = Fre+uou F'x+u'oug'u F’e+u'oug'ug’uF’2+ &e.
or, if we write x for u, and u for x, which in no way changes
the function F(x + u).
F(u+2) = Fut+2o2 Futs*org's F'utaorg'xo'x Fu + &e.
If we here observe, that whas no limit of diminution, and
if we denote by FO, F’0, F’0, &c., the limits of Fu, or the values
to which these funttions are reduced by the substitution of a
zero for the symbol denoting its root, we shall obtain ultimately
from this formula the following equation.
Fx = FO + xox F'0 + wor g'x F'0+ wx o'a o'r F'0 + &e.
and in this most general expression consists the solution of the
problem proposed.

In the subsequent sections the author proceeds to introduce
more particular values, for such of the quantities as here remain
indeterminate : but you will be able to judge of the method that
he employs by the first section, of which I have given you a

360 Astronomical and Nautical Collections.

translation. For my own part, I think that the substitution of
F'(2,w) in an argument inferred from reasoning on F(x + u), as
well as the exchange of a for u and u for «, when u only had
before been supposed evanescent, requires something more of
illustration than the learned.and accomplished author has here
thought it necessary to bestow on it, though I am not at all dis-
posed to deny the general validity of his reasoning, or the truth

‘of his conclusions.
Believe me, dear Sir,

Yours, very sincerely,
* *

London, 19 May, 1823.
iv. An easy Method of computing the Time of Conjunction in
Right Ascension from an observed OCCULTATION.

1. Observe, if possible, the difference of apparent altitudes at
the time of immersion, or emersion; if not, compute it either
by finding the altitudes separately, or from the differences of
declination, and right ascension, allowing for the change of de-
clination between the conjunction in right ascension at Green-
wich, and the time of immersion, by reckoning ; and reducing
the difference of declination in the ratio of the radius to the
cosine of the parallactic angle (P) Z), and that of right ascen-
sion in the ratio of the radius to the cosine of the same angle.
(See Astr. Coll. No. III.)

II. The true distance at the time of immersion may be found,
as in the correction of a lunar observation, by the method in the
Appendix to the Requisite Tables, observing that the Reserved
Logarithm will become simply log. (cos. P’ — sin. A’ sin. P), P
being the horizontal parallax, P’ the parallax in altitude, and
A’ the apparent altitude. This multiplier, however, may be
altogether omitted without inconvenience, and the triangles may
be treated as plane instead of spherical, the square of the-true
distance being equal to the sum of the squares of the semi-
diameter and of the difference of true altitudes, lessened by the
square of the difference of apparent altitudes.

Ill. The square of the true distance being thus obtained, the
‘distance of the star from the orbit may be found by reducing
the difference of declinations at its conjunction in right as-

Astronomical and Nautical Collections, 361

cension, in the ratio of the radius to the sine of the
orbital angle ; and the square of the nearest distance,-being sub-
tracted from the square of the true distances, will give the
square of the distance from the point of the orbit nearest to the
star, the place of which in the orbit is found from the cosine of
the orbital angle. And in all these cases, the natural verse
sines, taken from a good table, will serve instead of the squares.
The time of immersion is found from the place in the orbit by
means of the hourly motion, and may be employed for correcting
the declination, and repeating the operation, when necessary-

I. Example. Suppose the emersion of v {J to have been ob-
served at Paris, 1822, Feb. 8,10" 9™ 11*: and the difference
of altitudes of the star and the moon’s centre, either observed or
computed, to have been 2/36”: the semidiameter at the time
being 15’ 18”, and the parallax in altitude 52’ 1”, whence the
true difference of altitudes was 54’ 37”, the star being below the
moon’s centre.

‘ a”

II. The semi-diameter 1518 = 918 square 842724
True diff. alt... 5437 = 3277 10738729
Diff. app. alt. 0) 92136 156 A.C. 99975664
True distance . . 5640 = 3400 11557117

III. Now in order to find the point of the orbit nearest to the

star, we take the difference of declination at the conjunction,
P.L. 4158”. 6324

And add to it the log. ae pee faee

II

and the log. sec. 3289
Hence the distance is 37’ 4" "6863
the motion in the orbit 19’ 41” 9613
Then 37'.4” = 2224” square 4946176
Subtracted from 11557117
Gives 4261 =. 2571 6610941

Deduct 19 41
the remainder 23 10 is the motion in the orbit, which, at
the rate of 31’ 30” in an hour, gives 44™ 8°, to beadded to the
time of emersion, 10".9™ 11s, for the time of conjunction in
right ascension, making 10" 53™ 19%5 which differs only by a
second from the true term of conjunction, 10 53™ 18°.

362 Astronomical and Nautical Collections.

A table of square numbers, like that of Professor Barlow, will
be found very useful in these computations.

v. Remarks on Mr. Piana’s Researches relating to Refraction.
In a Letter to Professor GauTiER.
My pear Sir,

I believe it is to you that I am indebted, or perhaps
to Baron Zach, for the notice that Mr. Plana has been
pleased to take of my papers on Refraction: and I consider
myself as obliged to this justly celebrated mathematician,
not only for the flattering terms in which he has mentioned my
name, but also for the forbearance with which he has hinted at
what appears to him to be an unfounded objection to Laplace’s
hypothesis; at the same time, that he has endeavoured to sub-
stitute another objection to that hypothesis, which will, per-
haps, be still more easily superseded. I hope also to be al-
lowed, in return for these services, to set Mr. Plana right upon
a point of physical optics, respecting which he is both essen-
tially and accidentally in error: essentially, because, he mis-
takes the ground upon which I have founded my optical rea-
soning ; and accidentally, because the error, if it had existed,
would have been of no consequence whatever to the result.

I might, perhaps, be justifiable in complaining, that in a sec-
tion devoted to the history of the late researches on refraction,
Mr. Plana has only mentioned my attempts, in order to express
his surprise at this supposed error, and that he has not thought
it necessary to take the slightest notice of the real innovation
that I have ventured to make in the investigation. The history
of my paper might have been expressed very shortly, by saying
that it was “‘a Method of computing the Atmospheric Refrac-
tion, upon any possible hypothesis, by means of a series which
expresses the density in terms of the integer powers of the re-
Fraction itself; a series converging rapidly in all ordinary cases,
and converging sufficiently, even in the extreme cases near the
horizon. Mr. Plana not having noticed this distinguishing cha—
racteristic of my little invention, I shall endeavour to impress
it on his mind, by one more instance of the facility with which
it may be employed ; and I shall offer him, for this purpose, an

Astronomical and Nautical Collections. 363

example of its application to the hypothesis of Laplace, which
is expressed in so intricate a form, as not to be of the most
manageable nature, and as to be very liable to some misinter-
pretations.

My series, as it was actually employed for the construction
of the table printed in the Nautical Almanac, (Astr. Coll. VIL.

Be. if r2 r3 1 1
hi a oe 7 Bs?) ee Ce te CCR
lil.) is Bes tit 5s Meat fe ae ( =

ob es ; and I have demonstrated that A being = p, and c=
v

=, aud f= dé B must be C ‘and: C= he es
dz dr 2mp 6 \mpv

a ) , whatever may be the relations between the density z,
mp

and the pressure y: and if we put = = we shall have, still

x
more compendiously, C = g (i+ =) = Za+=);
6mp? m 3p m
since do pelts: and 2 = Eu
dr mpsz mpsZ

Now in the hypothesis of Laplace, ( Méc. Cél. X. §.'7. P. 264),
uy = 5 — 0,000293876 (I — & ); e = () [I + w. 661,107]
é

”

=-l1-

-™3804 5»? or, in the symbols of the series, “u
mt p(i—2z), andz= (1+ pu) e"; making 661,107 =
x
pw, and 1348,04 = ».
Hence, we obtain du = wy + pdz, and dz = pe—™ du —
LE

d
yzdu; and making pe” — vz = U, dz = Udu = U — a

U__ ae. and dy

1 —pU «xx

p Udz, dz — pUdz = yt, and dz =
Lx

being = — mzdz, dy _ f= —mzx* (-2") =mz*? (p—
dz U
5 — mx ya

UU

1). se , dU
>) ; consequently df = 2 re dx + ma ao

3646 Astronomiéal and Nautical Collections:

but dU = — poe 1% — vdz = — pre" * — vdz: and ini-

tially, when u = 0, UY =p —v, dz = ; dx, orify—yp
ane 5
—A v ™
= a, dz” — agi hi Es) we —aH a da
a, d rea C mp + py y
pa ie "dé, and a 2 of oe
H ig

‘The a oiaeeical values of the coefficients, taking m = fig as sup-

Be Tag ihn dic tgyd

widaed by Laplace, will be.B == —2— = 4+ ——_ - = 4a
2mp 2 22a. 2 1378.86

— 2,977, and C=? (1 + a ob Pegg: 2h Eee

3p 3p m — 1+pa

1348..x 25.82
“Y.2019 x 687 x 687
3141,(1.0074+4.0614)=3141 x 1.0688=3356. In the Nautical
Almanac, the values, obtained from the observed refractions only,
are B = 2.97 and C = 3600: and the difference in the results
of the computation will be insignificant even at the horizon.

It is almost unnecessary to remark, that a hypothesis, so well
supported by direct observation, can searcely be very materially:
erroneous. With respect to the variation of temperature in
ascending, we may represent it by making z = y(1 + txr— 4);
(Collect. VI. i. 7. D.); ¢ being. either constant or variable, ac-
cording to the conditions of the hypothesis; then if f be the
number of feet required for a:depression of a degree of Fahren=

(1 + 0074 +

hee au) .9923
AA P

heit, we shall have ¢ = 20.900.000,. andy = 43907 ; but
‘ ~~ a76f ’

da ies = + ty dx + (a — 1) ydts consequently ¢ = a
24 —@ = 84, and ae pee ee ede
uy ea yda yy Ax

Astronomical and Nautical Collections: 365°

— dt; whence 2d’ =d (= = @ dy ; and since dy
yda yy da dx
- fda ee ete mzz | mz »#a(= —
dx 2 yy yes & Xywy
li pe adam ae Ree te aed = = dz —
Cy y eye'y 4 y
1 dg éda édz
dy = (1 —Odz,and -d— = 2 = F- =- '
4 4 <4 me
dt~ m 1 1 m éy
and — = — (2-2 - — j IO em Var ee eae
di Bek -Fthr fh) = ye

=1— = ): Now we have found @ in the present case=1.396,
m

and £. = .0688; whence “% . =. (4.188 — 3,898 — 1
dz Ps &

m
— .069 = — 119 which being negative, it follows that ¢

increases with the elevation, as 2 diminishes, and that the varia-
tion of temperature becomes greater in ascending.

Mr. Plana has remarked, that “ en suivant les consequences
de Vhypothése de M. de Laplace, l’on pourrait ajouter, que la
pression barometrique, qui en résulte, est loin de s’accorder avec
celle observée par M. Gay-Lussac au point supérieur de son
ascension aérostatique.” I shall not undertake to criticize
Mr. Plana’s Memoir, especially without having had time to read
it through with attention; but I am utterly at a loss to conceive
by what witchcraft he has been able to compute the barometri-

‘cal pressure resulting from Laplace’s hypothesis at the height
attained by Gay-Lussac, if that height was only deduced from
the actual observation of the barometer. Perhaps, indeed, the
aéronauts were able to measure, with their sextant, a variety of
angles, subtended by distant terrestrial objects: and if such
was the fact, my question is answered.

. [shall now proceed to discuss the second passage in which
Mr. Plana has done me the honour to mention me. “Je crois
avoir reconnu,” he observes, (p. 301), que le Dr. Young west
pas parti de la véritable équation du probléme dans un de ses

366 Astronomical and Nautical Colleciions.

écrits, ayant pour titre Corrections for Refraction, Le D. Y.
aprés avoir pris pour base cette équation trés exacte [dd =
du
V(r? — ol

perpendiculaire w, dans la courbe décrite par le corpuscule de

, donnée antérieurement par Lambert, suppose la

lumiétre, telle que Yon au = 7 , 6 étant un constant con-

g

venable.” This value of w is inconsistent, he observes, with the
demonstration of Laplace and others, and he continues ; ‘* Pour
redresser cette erreur, il faut supposer 4 la variable u une ex-

b
v (1 + Mey
Young est tellement singuliére, que je crois de mon devoir de
rapporter ici Je raisonnement méme que ce physicien...a fait
pour établir son expression differentielle de la réfraction.” In
the passage quoted, I have called the refractive density 1 + pz,
“* p being a very small fraction.”

Mr. Plana does not seem to be aware that, in the theory of
optics, which I have long since advanced, and which has of late
years begun to acquire some considerable popularity, the de-
monstration, to which he alludes, as deduced from the laws of
central forces, is wholly inadmissible, except as a mathematical
fiction: and he must show, that the refractive density does not
vary in proportion to the actual density multiplied by a very
small fraction, and increased by unity, before he can establish
this charge. But even supposing it established, that I ought
to have taken ,/(1 + Mg) instead of 1 + pg, it is quite clear,

that since / (1 + Me) = 1+ 2 Me -+ M* ¢%...and since

pression de la forme u = . Cette méprise du Dr.

e is always less than unity, the error could only amount to

= of the square of the coefficient M, that is, to the square of

1
1700

, and that such an error would have been wholly insensible.

Believe me, dear Sir, yours, very sincerely,
9 June, 1823. eR *

Mechanical Science. 367

Art. XIV.—MISCELLANEOUS INTELLIGENCE.

I. Mecuanicat ScieNncrE,.

1. Bridge at Menai Straits.—The first great iron plate for
forming the fastening of Menai bridge was laid in its proper po
sition in the bottom of one of the caverns which had been
formed out of the solid rock on the Anglesea shore, on Easter
Monday. Sir Henry Parnell and Mr. Telford attended on the
occasion, and did not leave until all the necessary: arrange-
ments were adopted for proceeding immediately with the
putting up of the large quantities of the iron-work which have
arrived from Shropshire, for forming the suspending cables.
Nearly the whole of the bridge masonry is completed, the
pyramids for supporting the cables of 50 feet in height above
the top of the main piers will be finished early in summer, and
the iron-work is going on so rapidly at Mr. Hazeldine’s forges,
that there is a certainty of this great work being completed in
the most satisfactory manner for the use of the public, in little
more than another year.

2. Gas Lighting.—The length of streets already lighted in
this metropolis with gas is 215 miles! and the three principal
companies light 39,504 public lamps, and consume annually
about 33,158 chaldrons of coals.

3. Artificial Formation of Haloes.—The following experi-
ment, which illustrates in a pleasing manner the actual forma-
tion of haloes, has been given by Dr. Brewster. Take a
saturated solution of alum, and having spread a few drops of
it over a plate of glass, it will rapidly crystallize in small flat
octoédrons scarcely visible to the eye. When the plate is held
between the observer and the sun or a candle, with the eye
very close to the smooth side of the glass plate, there will be
seen three beautiful haloes of light at different distances from
the luminous body. The innermost halo, which is the whitest, is
formed by the images refracted by a pair of faces of the
octoédral crystals, not much inclined to each other; the
second halo, which is more coloured, with the blue rays out-
wards, is formed by a pair of faces more inclined; and the
third halo, which is very large and highly-coloured, is formed
by a still more inclined pair of faces. Hach separate crystal
forms three images of the luminous body placed at points 120°
distant from each other in all the three haloes; and, as the
numerous small crystals have their refracting faces turned in
every possible direction, the whole circumference of the haloes
will be completely filled up.

The same effects may be obtained with other crystals, and
when they have the property of double refraction, each halo

Vox. XV. 2B

368 Miscellaneous Intelligence.

will be either doubled when the double refraction is considerable,
or rendered broader or otherwise modified in point of colour,
when the double refraction is small. The effects may be cu-
riously varied by crystallizing upon the same plate of glass
crystals of a decided colour, by which means we should have
white and coloured haloes succeeding each other.—Edin.
Phil. Jour. vii. 394.

4. On the Electricity produced by Pressure.—A very import-
ant paper, on. the developement of electricity by pressure, and
the laws of that developement, by M. Becquerel, is to be found
in the Annales de Chimie, xxii, 5. We cannot do more at pre-
sent than translate the summary given at the conclusion of the

aper.

: It is seen, then, that all bodies assume two different electric states
by pressure: that,.in two. bodies being perfect conductors, this
state of equilibrium ceases, at the moment the pressure is re~
moved, but if one be a bad conductor, the effect of the pressure
continues for a longer, or shorter time,: that the pressure alone
maintains the equilibrium of the two fluids, placed on each of
the surfaces ; for if the pressure be diminished, and, at the end
of a certain time, the bodies be removed from the compression,
they wili be found to have the electricity, due only to the last
or remaining pressure: that heat modifies the developement of
electricity in a particular manner : that the intensity of the elec-
tricity increases, at first, directly as the pressure ; and that it is
probable this proportion diminishes at high pressures, as the
bodies lose their power of being compressed: finally, it is ren-
dered probable, that the light which is disengaged in powerful
concussions, is due to the rapid recombination of the two elec-
tric fluids developed on the surfaces at the moment of com-
pression.

5. Light evolved by Pressure.—We extract the following
passage from the paper above referred to. Considering the
increased developement of electricity in bodies, by the augmen-
tation of pressure, ought we not to refer to this cause certain
luminous phenomena, of which the origin is as yet unknown?
For instance, it is said, that in the Polar Seas, it frequently
happens, that the blocks of ice which strike together evolve
light. ‘These enormous blocks arriving one against the other,
with considerable motion, will be submitted to great pressure,
and thus the two blocks be placed in two different electric states.
At the moment the compression ceases, the two fluids will re-
combine, in consequence of the conducting power of the ice ;
and may not the light disengaged be the result of the combi~
nation of the electric fluids *?

* See also the light from the falling of a glacier, ix. p. 426.

Mechanical Science. 369

Tron, submitted to successive blows, also becomes luminous.
Are not the same electric phenomena of pressure produced
here, as when two masses of ice strike together ?

6. Developement of Electricity by two pieces of the same metal.—
Among the applications of the electro-magnetic multiplier, is
the following :—If two pieces of the same metal are plunged, at
different moments, into an acid capable of acting on them, that
which was first introduced will act as the most positive metal
to the other. The experiment may be made very well with
zine and diluted muriatic, or sulphuric acid.—Avogadro, An-
nales de Chim.

7. Variation of Thermometers.—In the last volume of this
Journal, p. 441, notice was taken of an observation made by
M. Flaugergues on the instability of the freezing point of ice, as
laid down onthermometers. The effect was not observed in alco-
hol thermometers or in mercurial thermometers open at the top,
and was attributed to the gradual yielding of the glass bulb to
the external atmospheric pressure, which, diminishing its bulk,
raised the surface of the mercury in the tube, and rendered the
scale incorrect.

M. Bellani has entered into the investigation of an analogous
error in thermometers, and published the result of his researches
in the Giornale di Fisica, v. 268. He finds that a mercurial ther-
mometer, being made in the usual manner, and the freezing
point of water marked on it from experiment, if it be laid
aside awhile, and again plunged in melting ice, the mercury will
stand higher than before; and that if it be put aside again, and
then again tried, the mercury will be higher still, until, at the end
of a certain time, a year or so, the effect of elevation will cease,

It was found from numerous experiments, that the result was
not influenced by the various qualities of the glass used in the
instrument; by the more or less perfect exclusion of air from the
bulb or tube; by the constant horizontal, perpendicular, or in-
verted position of the instrument; by the open or closed ex-
tremity; by the longer or shorter time of remaining in the ice ;
or by the compression of the surrounding ice. Neither was it
found to be peculiar to mercurial thermometers, but was ex-
hibited by alcohol thermometers, though in a less degree.

M. Bellani at last ascertained, that the effect was due to a
gradual and slow contraction of the glass after having been
highly heated, which contraction, as long as it continued, di-
minished the bulk of the instrument, and consequently forced
the fluid into the tube. This effect he illustrates in the follow-
ing manner :—Take a Florence flask, or any similar thin glass
vessel, such as a matrass with a long narrow neck, shortly after
it has come from the glass furnace, it not having been annealed

2B2

370 Miscellaneous Intelligence.

in the oven; introduce shot or sand into it till it almost:sinks in
water, seal it hermetically, and draw out one part of the neck
until not more than a line in diameter, that part being about an
inch in length; fasten a small basin on the top of the neck with
wax, and then, putting the instrument in water of a certain tem-
perature, 40° F. for instance, put weights in the cup till the
surface of the water is at the middle of the narrow part of the
neck; then lay the instrument aside for some days, or better
still, some weeks or months, and after that time, again immerse
it in the same water at the same temperature and pressure, and
with the same weight; the instrument will now sink lower than
before, in consequence of its diminished bulk from gradual con-
traction of the glass.

It was found that, although the effect was greatest after the
glass had been rendered soft by heat, yet that it occurred also
when the elevation of temperature had not extended nearly to the
softening of the glass, and indeed more or less upon every rise
of temperature. We have referred to an illustration of this at
p. 160 of our last Number. Hence two kinds of irregularity in
thermometers arise from the same cause, The one is mani-
fested soon after the formation of the instrument, increases to
a certain degree, and then remains stationary: this may be
rectified by elevating the scale of the instrument the required
quantity. The other takes place at every change of temperature ;
it is small and scarcely perceptible, with small changes of tem-
perature, but by considerable changes becomes very evident
and important.

Singular consequences sometimes result from the influence
of these changes. If two liquids be taken of different tem-
peratures, a greater difference will be found between them,
by trying the hot fluid, and then the cold fluid by the same
thermometer, than what will appear to exist by trying the cold
fluid first. Again, if a new thermometer be graduated by an
old one preserved as a standard, although it may be made to
agree with it, yet, after a while, the two will not accord; and
if two old thermometers be taken that do agree, and the one be
heated whilst the other remains unused, they will no longer in-
dicate the same temperatures.

The reason now becomes evident, why alcohol thermometers
are so much less affected in this manner, than those filled with
mercury. Alcohol expands several times more than mercury,
so that an instrument constructed with it having a tube of the
same diameter, and degrees of the same size, will require a
bulb several times less than if mercury had been used. Hence,
as the elevation. is in proportion to the capacity of the bulb,
independent of the liquid it contains, the alcohol thermometer
will exhibit a much smaller effect than the mercurial instrument.

Mechanical Science. 371

8. Variation of Thermometers.—MM. A. de la Rive and F.
Mareet, have also investigated the elevation of the mercury in
thermometers, which is due to the cause pointed out by Mr.
Flaugergues, (xiv. 441,) namely, the continued pressure of the
air on its external surface: and by opening the top of the thermo-
meter ; by submitting the instrument to condensed or rare at-
mospheres; and by comparison with thermometers otherwise
constructed, have abundantly proved the effect due to this
power. These philosophers had occasion also to remark some
curious effects due to the absorption and evolution of heat, by
the expansion and condensation of gases, which, however, we
cannot at this time further attend to, than by copying the
conclusions at the end of the memoir.

1. That atmospheric pressure exerts an influence on the bulk
of thermometer bulbs. 2. That in experiments, where this effect
may influence the results, it is better to use thermometers open
at the top. 3. That certainly cold is produced in making a
vaccuum by the air pump, but in smaller quantity than was sup-
posed *. 4. That when gases enter an exhausted vessel, there
is at first a production of cold, and then of heat. 5. That
various modifications may render the cold produced at the
moment of the entrance of air into a vaccuum, more intense.—
Bib. Univ. xxii. 265.

9. On Variations of Barometers and Thermometers.—Sig. Bel-
Jani has undertaken a series of experiments, to determine whether
the air or vapour, the last portions of which are found to remain
so obstinately in barometers and thermometers, is introduced
with the mercury, or is a portion of that which originally occu-
pied the tube before the introduction of the metal. The con-
clusion he comes to is, that it is always a portion of that which
previously adhered to the glass, and that mercury is utterly in-
capable of absorbing either air or moisture. The extraordinary
way in which air and water is held at it were in a film over
glass, is insisted upon, and reference made to many authors in
proof of it. The following, however, are more interesting, as
being some of the facts he advances to prove that the mercury
never contains either of these substances. Fill a barometer
tube and boil it very carefully ; then prepare a kind of funnel
made of a small capillary tube, which will reach through the
mercury in the barometer tube to the closed end, and is enlarged
at top; let it be recently made, so as to be dry, and intro-
duce it into the barometer tube; prepare some mercury by agi-
tating it in a bottle with water and air, then drying its surface
with bibulous paper, and afterwards passing it through paper
cones three or four times into dry vessels; pour a little of this

* It has been stated, that when one of M. Breguet’s metallic thermome-
“ers has been used, the diminution of temperature has amounted to 509.—
D.

372 Miscellaneous Intelligence.

mercury into the funnel tube, and with a horse-hair or fine wire
remove the air, so that the column may be continuous; then
pour in so'much of this prepared mercury as will fully displace
the mercury that was boiled in the tube; afterwards remove the
funnel tube, and put the barometer to its proper use. It willbe
found to stand exactly at the same height as before in the same
circumstances; and if the mercury be now boiled in the tube
none of those bubbles will appear which arose on the first boil-
ing; care being taken throughout, that the inner surface of the
tube has not been exposed to the air.

Perhaps an easier mode of making the same experiment is to
make the barometer terminate at top in a bulb, which will hold
more mercury than is required to fill the tube: then when it is
boiled it need only be placed upright in a basin of common
mercury, and when inclined the mercury will enter and replace
that which was boiled in the instrument; the results will be as
above, .

An experiment proving the same thing may be made still more
easily thus: fill a mercurial thermometer and boil it well; then
heat it till nearly all the mercury is expelled, but preserve its
open extremity under common mercury: the latter metal will
enter as the instrument cools, and behave in every respect as
the well-boiled mercury did.—Giornale di Fisica, vi. 20.

10. Maximum Density of Water.—The maximum density of
water is a point which, though frequently spoken of and sought
after, has never been accurately ascertained. Mr. J. Crichton,
of Glasgow, who has lately been engaged in determining the
specific gravity of certain fluids by means of adjusted balls of
glass, was so satisfied with the simplicity and accuracy of the
method, that he determined to apply it to the investigation of the
point above mentioned, and after much careful experiment has
fixed it with apparently great accuracy at 42. 3°F.

In a first experiment with these balls, one, which was just
poised in water at 33°, had the same property near 51° this
gave 42° for the point of greatest density, supposing the expan~
sion equal for equal differences of temperature above and below
the maximum density.

Many precautions are required in these kind of experiments :
whilst cooling the water it should be kept as still as possible,
agitation charging it with air; the presence of air-bubbles
should be very carefully attended to, for when one happens to
adhere to the ball, the experiment is vitiated. An uniform tem-
perature should be attended to in every part of the mass of
water, and the absence of currents ascertained. The delicacy
of the ball itself may be imagined, when it is understood that
the removal of the 6000th part of a grain, or as little as could
possibly be ground off, has been too much. At first spherical
balls were used, but afterwards they were made in the form of

Mechanical Science. 373

parabolic spindles, sharp at the ends, of about an inch in
length and ;4, in diameter. In order to ensure perpendicularity
of the axes, before such a ball was hermetically sealed, a small
globule of mercury was introduced, which effectually answered
the purpose. |

The mode of observation was as follows :—A jar with distilled
water, thermometers and a bulb being arranged, the tempera-
ture being so low that the ball remained at the bottom of the
water, was carefully watched with alarge lens until the ball quitted
the bottom, and at this moment the thermometers were noted.
When the ball had risen a little, a small rod was cautiously let
down, and, without agitating the water, gently made to touch the
ball; it descended, but instantly rose: this is a very delicate part of
the experiment, and if overdone loses its effect. It was repeated
frequently, and the ball re-ascended each time with accelerated
velocity. The thermometer indicating an increasing tempera
ture, the ball finally became stationary at the surface; from time
to time it was touched as before, but, as the temperature rose,
the tendency of the ball to ascend, judging by the velocity
with which it did so, each time diminished. Its upper ex-
tremity, by degrees seemed to press more feebly on the surface
of the water, till at last a fine thread of separation became
visible. The degree by the thermometers was again marked,
and, as they continued slowly to rise, the ball gradually fell to
the bottom of the jar. The intermediate point, between the
two points noted, was then ascertained, and considered as the
point of maximum density of the water. It appeared, from
all the experiments, to be a little above 42°; and, from one
experiment, as before mentioned, to be 42.3°.—Ann. Phil.
N.S. v.

11. Tenacity of Iron Wire.—At page 136, an account is given
of an economical wire suspension-bridge erected at Annonay, by
M. Seguin. It was expected that the difference of temperature
at different seasons would influence the strength of this and
similar bridges, and render it weaker at one time than another.
M. Dufour has, therefore, undertaken some experiments, with
a view of ascertaining any change in tenacity dependent upon
such alteration of temperature. Some iron wire was procured,
iy of an inch in diameter, and the weight required to break it
ascertained from the mean of several experiments. A portion was
then passed through a hollow vessel, filled with a frigorific mix-
ture, which lowered the temperature to — 8° F. In three experi-
ments, in which wires, thus circumstanced, were broken by
weights applied to them, the separation took place out of
the vessel, and the weight required was the same as before.
The vessel was then filled with boiling water, and the wire
passing through it tried as before. It broke once in the vessel,
and once out of the vessel, the latter by the smaller weight.

374 Miscellaneous Intelligence.

Finally, two vessels were then disposed on the wire, one con-
taining the frigorific mixture, the other boiling water; the wire
gave way between them, requiring the same weight as before.

It may thus be considered as demonstrated, that between the
limits of temperature indicated 7. e., 212° and — 8° F.; change
of temperature has no influence on the tenacity of iron wire.
— Bib. Univ., xxii. 220.

12. Electro-Magnetism. New Experiments by M. Seebeck on
Electro-Magnetic Action.—This gentleman, member of the aca-
demy of Berlin, has discovered that an electrical circuit can be
established in metals, without the interposition of any liquid.
The electrical current is established in this circuit by disturbing
the equilibrium of temperature. The apparatus for exhibiting
this action is very simple. It may be formed of two arcs of
different metals ; for example, copper and bismuth soldered to-
gether at the two extremities, so that together they make a
circle; it is not even necessary that the metallic pieces should
have the form of an arc, or that their union have that of
a circle; it is enough if the two metals form together a
a circuit ; that is, a continuous ring of any figure. To establish
the current, we heat the ring at one of the two places where the
two metals are in contact. If the circuit be composed of copper
and bismuth the positive electricity will assume; in the part
which is not heated, the direction of the copper towards the bis-
muth; but if the circuit be composed of copper and antimony,
the direction of the current, in the part not heated, will be from
the antimony towards the copper. These currents can be dis-
covered only by the magnetic needle, on which they exercise
a very perceptible influence. Henceforth we must distinguish
this new class of electric circuits by a significant denomination ;
as such, the expression thermo-electric circuits, or perhaps therm-
electric, are proposed. We can, at the same time, distinguish
the galvanic circuit by the name hydro-electric.—See xiv. 42.

13. On the Oscillations of Sonorous Chords.—In a science of
such universal interest. as music, which is the object of dis-
cussion, not only of the musician, but of the mathematician and
the natural philosopher, it is remarkable what a discordance of
opinion there exists with regard to those sounds called harmo-
nics, and even with regard to the oscillations of sonorous
chords. The following interesting theorem removes all obscurity
from these subjects.

If any two sonorous chords, A and B, be so placed, as that the
oscillations of one shall cause the air to act upon the other, as in
all stringed musical instruments, and if A oscillates, m times,
while B oscillates m times, m and n, being any whole numbers
prime to each other; then, if either of these chords, as A, is
put in motion, the action of the air will divide B into m equal

Chemical Science. 375

parts, each of which will oscilate n times, while A oscillates
only once. :

This theorem is the base of the theory of harmonics. It was
deduced from a property demonstraied by Lagrange, in Sect.
6. Mec. Analytique, that a vibrating cord is susceptible of being
divided into any number of equal parts, each of which would
vibrate as if isolated. It affords a refutation of (what geometers
seemed not absolutely to doubt) the assertion of Rameau, that
every fundamental note in music is accompanied with its octave,
twelfth, and seventeenth. It proves that, whether a sonorous
homogeneous chord of uniform solidity has one, two, or three
species of vibrations, these oscillations being necessarily per-
formed in equal times, it cannot produce but one single note at
atime. It is remarkable, that while the illustrious geometer
just named had the proof of the fallacy of the received theory of
harmonics before him, he was framing an hypothesis to account
for its truth.

ii. CHEMICAL SCIENCE.

1. A new Fluid discovered in Minerals.—A new fluid, of a
very singular nature, has been recently discovered by Dr. Brew-
ster, in the cavities of minerals. It possesses the remarkable
property of expanding about thirty times more than water ; and,
by the heat of the hand, or between 75° and 83°, it always ex-
pands so as to fill the cavity which contains it. The vacuity
which is thus filled up is of course a perfect vacuum, and, at a
temperature below that now mentioned, the new fluid con-
tracts, and the vacuity re-appears, frequently with a rapid
effervescence. These phenomena take place instantaneously
in several hundred cavities, seen at the same time. The new
fluid is also remarkable for its extreme volubility, adhering very
slightly to the sides of the cavities, and is likewise distinguished
by its optical properties ; it exists, however, in quantities too
small to be susceptible of chemical analysis.* This new fluid is
almost always accompanied with another fluid like water, with
which it refuses to mix, and which does not perceptibly expand
at the above-mentioned temperature. In a specimen of cymo-
phane, or chrysoberyl, Dr. Brewster has discovered a stratum
of these cavities, in which he has reckoned, in the space of } of
an inch square, 30,000 cavities, each containing this new fluid,
a portion of the fluid like water, and a vacuity besides. All
these vacuities simultaneously disappear at a temperature of
83°. |

If such a fluid could be obtained in quantities, its utility in
the construction of thermometers and levels would be incalcu-
lable. There are many cavities in crystals, such as those opened
by Sir Humphry Davy, which contain only water, and which,
of course, neyer exkibit any of the properties above described.

376° Miscellaneous Intelligence.

An account of these results was read before the Royal Society
of Edinburgh, on the 3d and 17th of March.—Edin. Phil. Jour.
viii. 400.

[We have seen a most curious and satisfactory specimen of
amethyst quartz, containing the fluid above described by Dr.
Brewster, in the collection of Thomas Allan, Esq. of Edinburgh.
It exhibits three distinct oblong cavities, which, when the crys-
tal is very slightly warmed, are to all appearance empty, but,
upon cooling it by immersion in water, or by holding it against
any cold substance, a portion of liquid is immediately perceived
in each of the cavities, which gradually disappears as the crys-
tal becomes less cold. The appearances aresuch as one might
expect would arise from very highly condensed carbonic acid
contained in the bubbles, assuming alternately the liquid and
gaseous form, by very slight elevations and depressions of
temperature.—Ep. |

2. Crystallized Deposit in the Essential Oil of Bitter Almonds.
Mr. Hendrie has just put into my possession a considerable
portion of white crystalline matter, which, he observes, always
separates from the above oil, when it is kept for some time,
partially exposed to air. The crystals are flattened rhombic
prisms. When cleared.of the adhering oil, they are transpa-
rent, somewhat acrid and gritty upon the tongue, fusible and
volatile at a heat of about 300°—insoluble in water, but readily
and abundantly soluble in ether and alcohol; the latter depo-
siting a white powder, when mixed with water. They dissolve
in solutions of ammonia, potassa, and soda, and are not de-
composed when boiled with nitric acid. Their further proper-
ties I have not yet had an opportunity of examining, but the
above shew that they are peculiar.—W. T. B.

3. On a new Compound of Iodine. Iodide of Carbon ?—
I Signori Ferrari e Frisiani, whilst preparing the iodate and
hydriodate of potessa, observed the production of a new com-
pound of iodine. It may be obtained thus :—Heat an ounce of
iodine, with a little water, on a sand-bath, and add to it, by
degrees, about two ounces of potash; when the two salts above
mentioned will be formed. In order to saturate the excess of
alkali, pour in, by degrees, a tincture composed of one ounce
of iodine to six ounces of alcohol, specific gravity .837. When
the re-action of the tincture on the potash is finished, pour the
hot liquor on a filter, and the liquid which passes through will,
as it cools, deposit yellow crystals, of the substance; they
should be carefully washed in cold water, to remove all the
iodate and hydriodate of potash. Another method is, to take
the alcoholic solution of the two salts, prepared as above, and
distil it; and when the fluid which comes over ceases. to be
coloured, to change the receiver; the colourless liquor then
obtained, upon cooling, deposits very pure crystals, of the sub-

Chemical Science. 377

stance in question. If the distillation be suspended from time
to time, and the retort allowed to cool, beautiful crystals of the
substance form init. If strong alcohol be used in the above
operations, and but little water, then, upon adding water to the
filtered liquor, the substance is precipitated in abundance.

This substance is solid, of a lemon yellow colour, tastes like
nitric ether, and has an odour like that of saffron. Its form is
a compressed hexahedron (esaedro schiacciato). It is insolu-
ble in water, alkalies, or acids, but soluble in alcohol and
ether. It fuses and sublimes by a gentle heat, but at a higher
temperature becomes discoloured, is decomposed, and evolves
vapours of iodine, leaving behind a mere trace of carbon.—
Giornale di Fisica, vy. 241.

Il Sig. Taddei has more lately resumed the examination of
this substance, particularly with regard to its composition. He
recognises in it the same body as that discovered by M. Serullas,
and which the latter chemist formed in various ways, as by the
action of potash on an alcoholic solution of iodine; by the action
of alloys of potassium and antimony on a similar solution; and
by passing water and iodine in vapour over hot charcoal.

Taddei found the substance to act on mercury, copper, and
silver, forming iodides of these metals. When raised to a high
temperature it was decomposed, hence he endeavoured in this
way to ascertain the presence of hydrogen in it. No gas could,
however, be obtained from it, and the absence of hydrogen was
considered as established. The presence of carbon was ascer-
tained in the residuum after decomposition by its producing
carbonic acid when burnt in oxygen, and by its converting sul-
phate of barytes into sulphuret, which, on treatment with an
acid, gave sulphuretted hydrogen gas.

The next object was to ascertain the quantities of the two
elements found in it. The iodine was estimated thus: a given
weight was decomposed by heat in a long tube of glass, and the
iodine washed out by alcohol; the solution was dilutedwith
water, and sulphuretted hydrogen gas passed through it; when
it was presumed that all the iodine had been converted into
hydroidic acid, the sulphur thrown down was collected, weighed,
and the quantity of iodine inferred by the theory of proportional
quantities. The carbon was carefully collected, introduced into
a porcelain tube, to one end of which was attached a bladder
containing a portion of oxygen, whilst from the other a tube led
to a mercurial apparatus; the tube was then heated, the charcoal
burnt, and its quantity estimated from the quantity of carbonic
acid gas produced. Nearly the same experiment was repeated
on the original iodide of carbon, and the same quantity of car-
bonic acid gas obtained.

The results of these experiments give the proportion of the
carbon to the iodine as | to 17 by weight, and M. Taddei
concludes, therefore, that the substance is a protiodide of carbon.

378 Miscellaneous Intelligence.

It ought, however, to be noticed that M. Serullas considers the
body as a triple compound of carbon, hydrogen, and iodine,
analogous to the one described by Mr. Faraday, as do also
I Sig. Frisiani and Ferrari, but they have given no precise expe-
riments on the subject. A proportion of hydrogen would make so
small a part of the weight of the substance as easily to escape
notice, unless carefully looked for.—Giornale di Fisica, vi. 65.

An elaborate paper has also appeared on this subject, by M.
Serullas, in the Annales de Chimie, xxii. 172; for a full ac-
count of which, see the Foreign Science, p. 297. By his analy-
sis, it appears to be a triple compound, and not an iodide of
carbon; and it is remarkable, that the composition he has given
is as nearly as possible that of the compound, described and
analyzed by Mr. Faraday.—Scee Vol. xiil. p. 429.

4. Triple Compounds of Chlorine.—M. Despretz has read a
memoir on this subject to the Academy of Sciences; the liquids
which principally engaged his attention were those produced by
the action of chlorine on olefiant gas, alcohol, and ether. The first
of these liquids has been considered as a compound of equal
volumes of chlorine and olefiant gas, a result which was con-
firmed by direct experiment. As to the liquid formed by the re-
action of chlorine on alcohol, it proved to be a compound of
one volume of chlorine and two of olefiant gas. The two liquids
obtained by chlorine from ether have not been so accurately
examined; but one of them is considered as a new compound of
chlorine and olefiant gas.

In examining the action of olefiant gas on the chlorides of
sulphur and iodine, M. Despretz observed some remarkable re-
sults. The chloride of iodine gave two substances, the one a
colourless liquid with an agreeable taste and smell, and crystal-
lizing in plates at 32°; the other resulting from the action of a
greater quantity of olefiant gas, was white, solid, and crystalline.

With chloride of sulphur, a viscid liquid was produced, more
fixed than water, of a disagreeable odour, and difficultly com-
bustible.—Ann. de Chim. xxi. 437.

5. Action of Chlorine on Muriate of Iron, §c.—M. Van Mons
saturated a concentrated solution of proto-muriate of iron with
chlorine ; it became of a deep brown colour, did not give out the
odour of chlorine, tasted very astringent, and slightly acid,
and sweet. After some time, golden-coloured crystals formed
in the solution, and chlorine was developed in great abundance.
These crystals liquefied in the air, and could not be again crys~
tallized.

Gmelin, by passing chlorine through a solution of ferro-prus-
siate of potash, obtained a salt in fine rose-coloured crystals.
It was composed of two proportions of prussic acid, one pro-
portion of potash, and half a proportion of protoxide of iron.—
Giornale di Fisica.

Chemical. Science. 379

6. On the Preparation of Potassium and Sodium.—It is well
known to chemists, that the frequent failures in the preparation
of the alkaline metals arise from the high heat required in the
operation, which frequently fusing or cracking the lute on the
barrel, exposes it to the air and fire, when it is soon burnt, and
the product either partly or entirely lost. The object of
M. Brunner, who is the author of the following experiments,
was to perform the operation at a comparatively low tempera~
ture, which he has been enabled to effect by the following
apparatus.

The retort is a spheroidal iron bottle, about half an inch in
thickness, and capable of holding about a pint of water; a gun-
barrel bent into this form ({‘) screws into it at the shorter end.
When the retort is charged and luted, it is placed in a furnace, _
so that the longer part of the bent gun-barrel may pass out at
the bottom, or in front, in a direction nearly perpendicular, the
bent part itself remaining in the furnace; and that it may be
protected from the fire, it is wound round with iron wire. The
receiver is a cylindrical copper vessel, with an opening at the
top to receive the end of the gun-barrel, and a tube passing
from the side to convey away the gas produced in the operation.
It is placed, when in use, in water or ice.

The following is an instance of its use : the retort was cleaned,
dried, and heated, and then four ounces of fused caustic potash
introduced in small portions alternately with six ounces of
iron turnings broken in a mortar, mixed with one ounce of pul-
verized charcoal. The whole was stirred together, and covered
with two ounces of iron turnings. The retort being luted, the
barrel adapted, the whole placed in the furnace, and a glass
tube attached to the end of the barrel, that the progress of the
operation might be watched, the fire was lighted, and the heat
gradually raised: in ten minutes an inflammable gas came
over, which in ten minutes more burnt with a violet flame, pro-
ducing much fume; in ten minutes more the green vapours of
potassium appeared. The receiver containing naphtha was now
adapted, so that the end of the barrel should dip into the fluid;
the liberation of gas was very rapid, and it frequently inflamed
spontaneously, burning with a white violet flame. In about
twenty-five minutes from the application of the receiver, the gas
diminished in quantity, and soon entirely ceased coming over;
the receiver was separated, and found to contain 150 grains of
potassium.

Eight ounces of fused sub-carbonate of potash, 6 ounces of
iron filing, and 2 ounces of charcoal treated in the same way,
gave 140 grains of potassium.

To ascertain the effect of the charcoal in these experiments,
3 ounces were mixed with 6 ounces of fused sub-carbonate of

380 Miscellaneous Intelligence.

potash. The result was much inflammable gas, a pyrophorus
powder, and 180 grains of potassium.

When iron alone was used, not a particle of potassium could
be obtained at the heat, to which only this apparatus could be
raised.

Crude tartar was then used ; it was introduced into the appa-
ratus and heated, till the acid was decomposed; then the tube
removed, cleaned, and again attached, and the heat raised as in
the ordinary process. The mean of many experiments gave
nearly 300 grains of potassium from 24 ounces of crude tartar.
Not more than an ounce of alkali was found at any one time in
the retort after the operation. When the tartar was previously
mixed with +, of charcoal, the product was greater.

' In the preparation of ‘sodium, caustic soda, and the subcar-
bonate of soda were both used at different times, and with the
same success as attended the former experiments.

M. Brunner remarks, that a large quantity of the metal con-
tained in the alkali, always disappeared in these experi-
ments ; and concludes, that it was carried off in vapour. He
endeavoured to condense it, but without success. He states, in
conclusion, that the apparatus is cheap and durable, having
served for as many as thirty operations: that the process is
easy and agreeable compared to that by iron at the high tem-
perature: and that, as the vegetable salts witha little additional
charcoal, are the best sources of the metals, so the process be-
comes very economical.— Bib. Univ. xxii. 36.

7. Hydrocyanic acid, Preparation of.—M. Pessina, of Milan,
prepares hydrocyanic acid in the following manner, which is said
to be much more economical than any other process known. Eigh-
teen parts of triple prussiate of potash and iron are powdered
very fine, and carefully introduced into the bulb of a small
tubulated glass retort, a very small tubulated balloon is then
attached to the retort; it is furnished with a conducting tube
which dips into the first flask, containing a little distilled water.
The rest of the apparatus is contrived so as to prevent absorp-
tion. A cold mixture of nine parts of oil of vitriol, and twelve
parts of water, is then poured into the retort, the retort closed
and the whole left for 12 hours, the balloon being surrounded
with ice, and the neck of the retort constantly cooled with wet
cloths.—The materials are then to be heated a little, and con-
tinued so until the strize, which are observed in the neck of
the retort become more rare, and, until a blue substance rises,
which appears as if it would pass into the receiver. ‘The heat
is then to be discontinued, the apparatus allowed to cool, and
the contents of the receiver preserved in a proper vessel. The
hydrocyanic acid, thus obtained, is perfectly pure, and of a
specific gravity of 0.898 or 0.9. Its quantity, in relation to the

Chemical Science. 381

quantity of substances used, is not stated.—Giornale di Fisica,
v. 285.

8. Production of Cyanurets.—Cyanogen, according to M.
Brunner, is formed whenever a potash salt with a vegetable acid
is burnt with nitre:—ten parts of cream of tartar with one of
nitre, or two parts of acetate of potash with one of nitre, when
burnt, leave a product containing a notable proportion of cyan-
ogen. It has been shewn by M. Pagenstecher, that when eight
parts of nitre and five parts of tartar are burnt together, am-
monia is formed .

9. Iodide of Nitrogen.—M. Serullas describes the following
process, for the preparation of this detonating compound. Form
a sub-chloride of iodine, to which, add ammonia in excess ;
muriatic acid is formed, and the iodine is almost entirely com-
bined with the nitrogen, scarcely any hydriodate of ammonia
being formed. The solid substance produced, is to be thrown
on a filter, washed, and dried carefully. In the usual method,
scarcely a fourth part of the iodine enters into combination
with the nitrogen.— Ann. de Chim. xxii. 186.

10. Thenard’s Blue.—This blue is considered by M. Thenard,
as a combination of alumine and oxide of cobalt, and is prepared
in the following manner. Nitrate of cobalt prepared in the usual
way, from the ore of cobalt by torrefaction, digestion in nitric
acid, evaporation, and solution, is to be precipitated by a solution
of sub-phosphate of soda. The insoluble phosphate of cobalt is
to be well washed, and then collected together, whilst in the
gelatinous state, and mixed in the most perfect manner possible,
with eight times as much hydrate of alumina in the same state.
The mixture is spread on smooth plates, dried in a stove, when
hard and brittle reduced to powder, and heated in a covered
earthen crucible. After half. an hour’s ignition, it should be
taken from the fire, and should then be of the colour required,
The operation is always successful if the precautions be at-
tended to, andit is particularly important, that the gelatinous alu-
mina shall have been precipitated by an excess of ammonia,
and has been well washed with very pure water, until quite free
from impurity.

The arseniate of cobalt may be employed in place of the
phosphate, but it requires twice as much alumina to be mixed
with it.—Dict. Tech.—Tech. Rep, iii. 340.

11. On a Per-sulphate of Iron and Ammonia.—Dr. Forch-
hammer having prepared a solution of gold by means of nitric
acid and muriate of ammonia, and precipitated the gold by
proto-sulphate of iron, the clear solution was concentrated to

382 Miscellaneous Intelligence.

the consistence of syrup, and suffered to remain for a month ;
when beautiful octoédral crystals, of a wine-yellow colour, were’
formed on the sides of the vessel. On examination, it was
found to contain ammonia, and to be an alum, in which per-
oxide of iron supplied the place of alumina.

The salt dissolves in three parts of water at 60°, and, by re-
peated crystallization, may be obtained, perfectly colourless.
On careful analysis, 100 parts appeared to be composed of

Per-sulphate of iron. . 41.807
Sulphate of ammonia . 12.366
Sulphate of alumina . . 0.870
Water .

On further examination, Dr. Forchhammer found the sulphate
of alumina to be accidental, and neglecting it, ascertained the.
composition to be,

Per-sulphate of iron . . 41.95
Sulphate of ammonia . . 12.11
DWE, ELC PD | EGE

He considers it as identical with the salt formerly described by
Mr. Cooper, as a bi-persulphate of iron. =

As the results deducible from this analysis seemed to agree
so well with M. Mitscherlich’s idea, that per-oxide of iron and
alumina are isomorphous, and afforded additional proof of the
correctness of his views, Dr. Forchhammer was more earnest.
to ascertain the exact quantity of water, and to compare it with
ammonia alum; which salt gave, on analysis,

Sulphuricacid . . . . 35.90
Alominasesanantebnidoiar lal
AMMONIA is by. nies deni O

Water andloss. . . . 48.74

This alum is, therefore, composed of three atoms of sulphate
of alumina, one atom of sulphate of ammonia, and 24 atoms of
water—and the triple salt above described, of three atoms of
per-sulphate of iron, one atom of sulphate of ammonia, and
24 atoms of water.—Ann. Phil. v.

12. Test for Proto-salts of Iron.—Professor Ficinus, of Dres-
den, strongly recommends a solution of muriate of gold, as the
most delicate of all tests for the presence of protoxide of iron
in solution, surpassing considerably even the gall nut. It re-
quires the presence of. carbonate of soda, which, in some ana-
lyses, may perhaps interfere with its use. A grain of green
vitriol, with an equal weight of soda, dissolved in four pints of
water, produces, with a drop of solution of muriate of gold, a
strong precipitate, which gradually assumes a purple colour.
Without the soda, the effect did not appear in less than three

- Chemical Science. 383

days. M. Ficinus thinks the process may be improved even to
the determination of the quantity of protoxide of iron present.
Bib. Univ.

13. Test for Barytes and Strontia.—At p. 189, vol, x. is a
process to distinguish between barytes and strontian ; the repe-
tition of it in most of the chemical journals is a proof that such
a test was wanted. Mr, Smithson recommends the following
as better. Put a particle of the soluble salt formed, into a
drop of muriatic acid, on a plate of glass, and let the solution
crystallize spontaneously. ‘The crystals of chloride of barium,
in rectangular eight-sided plates, are immediately distinguish-
able from the fibrous crystals of chloride of strontium.

As a test between the sulphates of the two earths, Mr. Smith-
son directs, that the mineral, in fine powder, be blended with
chloride of barium, and the mixture fused. The mass is to be
put into spirit of wine, whose flame is coloured red, if the mine-
ral was sulphate of strontium. ‘The red colour of the flame is
more apparent when the spirit is made to boil, while burning,
by holding the platina spoon containing it over the lamp.—
Ann. Phil. N.S. v. 359.

14. Action of Phosphorus on Water.—Mz. Phillips has ascer-
tained, by direct experiments, that when phosphorus is preserved
in water, there is a mutual action attended with decomposition
of the fluid. The oxygen of the water forms, at first, oxide of
phosphorus, and, eventually, phosphorous or phosphoric acid ;
whilst the hydrogen, combining with phosphorus also, forms
phosphuretted hydrogen. These changes take place much
more rapidly when light has access, than in the dark,.—Ann.
Phil. N.S. .

15. Fixedness of Sulphuric Acid.—M. Bellani placed a thin
plate of zinc in the upper part of a closed bottle, at the bottom
of which was some concentrated sulphuric acid. No action had
taken place at the end of two years, the zinc remaining as
bright as at first. This fact is adduced in illustration of the
fixedness of sulphuric acid at common temperatures.—Giornale
di Fisica, v. 197.

16. Effect of a Vacuum on Alkaline Carbonates, by Doberei-
ner .—I have found that these carbonates, (bi-carbonates,)
when dissolved in the smallest quantity of water possible, or
when covered with water, and left for half an hour in a vacuum,
lose one-fourth of their acid. If, after being thus treated, they
are put in a graduated tube over mercury, and acted on by a
saturated solution of proto-sulphate of manganese, only about
half the quantity ef carbonic acid is set free, which may be

Vox. XV. 2C

384 Miscellaneous Intelligence.

obtained, if afterwards a sufficient quantity of acid be added, to
decompose the carbonate of manganese formed. These alkaline
carbonates are modified, therefore, like the radiated natron of
Tripoli, which I have ascertained to be composed as follows:

Bi-carbonate of soda, 1 = 30 soda + 41.4 carbonic acid
Carbonate of soda . 1 = 30 —— + 20.7 carbonic acid
Water. . eta peee!

The same compound, is formed, if one part of bi-carbonate of
soda, and four of water, be boiled until gas ceases to be libe-
rated. Ihave not as yet been able to obtain the radiated erys-
talline structure. —Bib. Univ. xxii, 123 *.

17. Formation of Calcareous Spar.—Mr. Haig, on pouring
out the contents of a bottle of Saratoga water, which had stood
several years in a cellar, found the bottom to contain well-
defined crystals of calcareous spar, which, on being split, ex-
hibited the usual appearance of that substance.—£din. Journ.

18. Action of Animal Charcoal on Lime.—Animal charcoal
is not only capable of separating colouring matter and extrac-
tive from solution, but will even remove lime from them. This
may be proved according to Payen, by boiling 100 parts of
lime-water for a few seconds with 10 parts of animal charcoal,
and. then testing the clear liquor by oxalate of ammonia; not a
particle of lime will be found in it. Vegetable charcoal, or
lamp-black, do not produce this effect.

19. Bizio on Virgin Wax.—Sig. Bizio has separated wax into
two substances: it is to be boiled in alcohol until the whole is
dissolved, and the solution then allowed to cool, and its tem-
perature lowered 10° or 20° below the freezing point; a large
quantity of white matter then separates, which is the wax; and
there remain in solution the colouring principle, and an acid
substance, which strongly reddens tincture of turnsole. The
solid precipitate being separated by a filter, the fluid was eva~
porated, and left a fatty substance, of the consistence of butter,
of a yellow colour, having the odour of honey, and melting at
a temperature of 116° F.—Giornale di Fisica, v. 374.

20. Separation of Elaine from Oils.—This process is due to
M. Pictet, and is founded on the property possessed by stea-
rine, of being saponified by cold strong alkaline solutions,
which does not belong to elaine. In order to, separate these
two substances, a concentrated solution of caustic soda is
poured on to oil, and agitated with it; it is then slightly

* See Mr. Phillips on Alkaline Carbonates.

a

Chemical Science. 385

heated, to separate the elaine from the soap of stearine; is
passed through a cloth, and, finally, the elaine separated from
the excess of alkaline solution, by decantation. This process
is successful with all oils, except those which are rancid, or
have been altered by fire. The elaine is perfectly identical with
that obtained by the processes of MM. Chevreul and Braconnot.
Ann, de Chim. xxii.

21. On the Clarification of Wine.—There is sold in France, and
at a very high price, relative to its value, a reddish-brown
powder for clarifying wines. It is prescribed, in employing it,
to put into a vessel the quantity of water or wine, which is usually
mixed with whites of eggs, to sprinkle gently the powder on the
liquid; and, when it is well mingled, to pour the mixture into a
cask, finishing the operation in the usual way. M. Gay-Lussac
says, that the clarifying-powder is nothing but dried blood, and
that he has prepared some with particular care in the desicca-
tion, which was even superior to that on sale. The whites of
two eggs contain as much albumen (which is the sole clarifying
principle) as the dose of powder prescribed for the clarification
of a cask of two hundred litres. It will be found more beneficial
to make use of the white of egg,—both in reference to economy,
and to that of the bad odour of glue possessed by the solution
of dried blood, which might affect the flavour of fine wines.
M. Gay-Lussec has prepared a powder, with the whites of eggs
dried, which has not the same inconveniences as blood, which
mixes easily with water, and clarifies very well.

Il. Narurat History.

1. Blumenbach on Irritability of the Tongue.—I had the tongue
of a four year old ox which had been killed in the common
way, by opening the large vessels of the neck, cut out in my

esence while yet warm, and at the same time the heart, in
order that might compare the oscillatory motion of this organ,
which is by far the most irritable that we are acquainted with,
with the motion of the tongue ; and, when I excited both
viscera at the same time, by the same mechanical stimuli,
namely, incisions with a knife and pricks of a needle, the
divided tongue appeared to all the bystanders to survive the
heart more than seven minutes, and to retain the oscillation of
its fibres altogether for a quarter of an hour ; and so vivid were
the movements when I cut across the fore part of the tongue,
that the butcher’s wife compared them to those of an eel in
similar condition, quite in the way that Ovid has compared
them to the motions of the tail of a mutilated snake.—LEdin.
Phil. Jour. VIL. 263.

2C2

386 Miscellaneous Intelligence.

2. Sensation experienced at great Altitudes,—Capt. Hodgson
in his journey to the head of the Ganges, which he found in
the midst of eternal snows, says, whilst speaking of the sen-
sations felt at great altitudes, “‘ We experienced considerable
difficulty in breathing, and that peculiar sensation which is
always felt at great elevations where there is any sort of
herbage, though I never experienced the like on naked snow-
beds, even when higher. Mountaineers, who know nothing of
the thinness of the air, attribute the faintness to the exhalations
from noxious plants; and I believe they are right, for a sickening
effluvium was given out by them here, as well as on the heights
under the snowy peaks which I passed over last year above the
Setlej, though on the highest snow the faintness was not com-
plained of, but only an inability to go far without stopping to
take breath. — Edin. Phil. Jour.

3. On the Action of Nitrogen in the Process of Respiration.—
Dr. Edwards, who is well known as an intelligent physiologist,
concludes, from different experiments, and from the circum-
stance of the opposite results which they give, some indicating
a diminution of the nitrogen of the air, others an increase of it,
during respiration, that this gas is absorbed into the circulation,
and afterwards discharged from it; and that each of these
actions is regulated by the constitution, habit, and circum-
stances of the individual, and by the influences to which he
may be subjected, the absorption being to a small extent, while
the exhalation is considerable, and vice versd.—Journ. de Phys.,
January, 1823.

4. Diabetes.—M. Van Mons says, “I have met with a very
singular diabetic urine ; it gives no indication of ammonia
with any chemical re-agent, nor does it possess the odour of
urine ; but this odour is strongly developed, and that also of
ammonia, at the same time accompanied by a brisk effer-
vescence, if a few drops of sulphuric acid be added to it.
These products are supposed to arise from the action of the
acid on the urea.—Gzornale de Fisica.

5. Toad in a Solid Rock.—The workmen engaged in blasting
rock from the bed of the Erie canal at Lockport in Niagara
county, lately discovered, in a small cavity in the rock, a toad
in the torpid state, which, on exposure to the air, instantly
revived, but died a few minutes afterwards. The cavity was
only large enough to contain the body without allowing room
for motion. No communication existed with the atmosphere,
the nearest approach to the surface was six inches through solid
stone. -It is: not mentioned whether the rock was sandstone
or limestone, but from the prevalence of limestone on the sur-

Natural History. 387

face of the contiguous country, it may be presumed to have
been the latter. The country is wholly of secondary formation.
Of the causes which enable animals of this class, which have
been suddenly enveloped in strata of earth, or otherwise shut
out from the air, without injury to the animal organ, to resume,
for a limited period, the functions of life on being restored to
the atmosphere, no explanation need here be given, as the
occurrence is a very common one, and is, perhaps, always more
or less the result of galvanic action.—Szliman’s Journal.

6. On the Sensitive Plant, (Mimosa Pudica). By M. Dutrochet.
—It is known that the movements of the leaves of this plant
have their origin in certain enlargements situated at the articu-
lation of the leaflets with the petiole, and of the petiole with
the stem. Those only situated in the last articulation are of
sufficient size to be submitted to experiment. If, by a longi-
tudinal section, the lower half of this swelling be removed,
the petiole will remain depressed, having lost the power of
elevating itself ; if the superior half be removed the petiole
remains constantly elevated, having lost the power of depressing _
itself. These experiments prove that the motions of the petiole
depend on the alternate turgescence of the upper and lower
half of the enlargement situated at the point of articulation, and
that contractibility is not the principle of these motions.

If one part of the plant be irritated, the others soon bear
witness, by the successive falling of their leaves, that they
have successively felt the irritation. ‘Thus, if a leaflet be
burnt slightly by a lens, the interior movement which is
produced is propagated successively to the other leaflets of the
leaf, and thence to the other leaves on the same stalk. M.
Dutrochet found, 1. That this interior movement is trans-
mitted equally well, either ascending or descending. 2. That it
is also equally well transmitted, although a ring of bark be re-
moved. 3. Thatit is transmitted also, even though the bark and
the pith be removed, so that nothing remains to communicate
between the two parts of the skin, except the woody fibres and
vessels. 4. That it is transmitted also when the two parts
communicate only by a shred of bark. 5. That it is trans-
mitted when the communication is completed by the pith only.
6. But that it is not transmitted when the communication only
exists by the cortical parenchyma. It results from these
experiments that the interior movement, produced by irritation,
_is propagated by the ligneous fibres and the vessels. ‘The pro
pagation is more rapid in the petioles than in the body of the
stem ; in the first it moves through from =3, to 38; of an inch in
a second, in the latter from 735 to 44%; of an inch in the same
time. External temperature does not appear to exert any

388 Miscellaneous Intelligence.

influence upon the rapidity of the movement, but very sensibly
affects its extent. .

Absence of light, during a certain time, completely destroys
the irritability of the plant. The change takes place more
rapidly when the temperature is elevated, than when low. The
return of the sun’s influence readily restores the plant to its
irritable state. It appears, therefore, that it is by the action
of light, that the vital properties of vegetables are supported,
as it is by the action of oxygen, that those of animals are pre-
served ; consequently, etiolation is to the former, what asphyxia
is to the latter.—Jour. de Phys. xcy. 474.

7. Vegetation in Atmospheres of different Densities.—The fol-
lowing experiments have been made by Professor Dobereiner of
Jena. Two glass vessels were procured, each of the capacity
of 320 cubic inches, two portions of barley were sown in por-
tions of the same earth, and moistened in the same degree, and
then placed one in each vessel. The air was now exhausted in
one, till reduced to the pressure of 14 inches of mercury, and
condensed in the other, until the pressure equalled 56 inches.
Germination took place in both nearly at the same time, and
the leaflets appeared of the same green tint; but, at the end of
15 days, the following differences existed. ‘The shoots in the
rarefied air were 6 inches in length, and from 9 to 10 inches
in the condensed air. The first were expanded and soft; the
last rolled round the stem and solid. The first were wet on
their surface, and especially towards the extremities; the last
were nearly dry. ‘‘I am disposed,” says M. Dobereiner “ to
believe, that the diminution in the size of plants, as they rise
into higher regions on mountains, depends more on the diminution
of pressure than of heat. The phenomena of drops of water on
the leaves in the rarefied air, calls to my mind the relation of
a young Englishman, who, whilst passing through Spanish
America as a prisoner, remarked, that on the highest moun-~
tains of the country, the trees continually transpired a quantity
of water, even in the dryest weather; the water falling sometimes
like rain.”—Bib, Univ. xxii. 121.

8. Fruit-Trees.—The growth of weeds round fruit-trees re-
cently transplanted does them much injury, and diminishes
their fruit in size and quality. Sonnini in his Bibliothéque
Physico-économique states, that to prevent this, the Germans
spread on the ground, round the fresh transplanted trees, as far
as their roots extend, the refuse stalks of flax after the fibrous
part has been separated. This gives them surprising vigour.
No weed will grow under flax refuse, and the earth remains
fresh and loose. Old trees, treated in the same manner when
languishing in an orchard, will recover and push out vigorous

Natural History. 389.

shoots. In place of the flax-stalks the leaves which fall from
trees in Autumn may be substituted, but they must be covered,
with waste twigs, or any thing else that will prevent the wind
from blowing them away.—Phil. Mag.

9. Mesotype from Mount Vesuvius.—Il Conte Paoli has
ascertained the existence of mesotype among the products of
Mount Vesuvius. He describes the fibrous mesotype and the
hyaline mesotype, and has no doubt of their being real volcanic
products formed in the lava at the time of cooling.

10. Native Sulphate of Iron and Alumina.—tThis is a salt
which has lately been found in abundance in the slate clay of
the deserted coal-mines of Hurlet and Campsie, and results
from the decomposition and mutual action of pyrites on the
clay. It was given by Mr. Macintosh to Mr. Phillips, who
describes it as existing in the state of soft, delicate, silky,
colourless fibres, resembling asbestos in appearance. By ex-
posure to moist air the iron becomes peroxidized. It dissolves
in water, yielding on evaporation crystals of sulphate of iron,
and a mother liquor of sulphate of alumina. Its solution with
salts of potash or ammonia yields alum. The salt on analysis
was found to be composed of

Sulphuric acid . . 30.9 or 4 atoms . = 160
Protoxide ofiron . 20.7... 3 bgian 2 08
y MAdamipia 58. 28 SIRE, 4 nel ee OT
Water 6 202 2 OAB2 MG QEE Yt mee A159
100 520

Ann. Phil.

11. Bitumen in Minerals.—In a curious paper upon the ana~
lysis of minerals, lately communicated to the Royal Society by
the Right Hon. George Knox, he demonstrates the existence
of bitumen in a great variety of mineral products where it has
hitherto escaped observation, such as basalt, greenstone, ser-
pentine, mica, §c.; and shows the necessity of attending to this
volatile ingredient in all cases of analysis, where it has been
generally suffered to escape observation from the loss by igni-
tion having too commonly been ascribed to water. He recom-
mends, with this view, that distillation, in a proper apparatus,
should always precede the other steps of analysis, and that the
nature of the volatile products, thus obtained, should be particu-
larly examined.

12. Italian Marble.—The workmen employed in working the
marble-quarry, discovered near Florence, proceed with activity ;
they have opened a way leading to Mount Altissimo, near Se~
varezza. The first blocks were sent to Paris, the others are

390 Miscellaneous. Intelligence.

teserved for Florence and Roine. These excavations will pro-
vide for Tuscany an important branch of industry and commerce.

13. Bagne Lake and Glacier.—A description was formerly given
(v. 372 and vi. 166.) of the singular lake which had formed in
the valley of Bagne, in consequence of the blocking up of the
river Dranse by a glacier, and also of the immense destruction
it occasioned by overthrowing its barrier, and escaping at once
into the lands beneath it. Up to the year 1805, no glaeier of
this kind existed, but a large one on the precipices above con-
tinually sent down blocks and masses of snow and ice, which
were removed by the waters of the rivers. It was the cold years
succeeding 1805 that gave rise to the permanent formation of the
lower glacier, for the masses of snow that fell into the river were
so large that it had not the power to remove them, though it
found a passage by filtration through them ; and then succeed-
ing winters hardened and consolidated the whole until it gave
rise to the catastrophe already described.

The event which then took place, did not remove the whole of
the lower glacier or barrier; on the contrary, scarcely a twen-
tieth part was broken down, and the river remained forced from
its old bed, and bordered on one side by the glacier, which ac=
cumulated so rapidly, that, at the end of 1819, the barrier to the
passage of the river was almost as complete as before its break-
ing up by the weight of the lake.

It became; therefore, an important object to prevent a repe-
tition of the former catastrophe, by the adoption of such means
as would diminish, or, at least, prevent the increase of the
barrier. Blasting by gunpowder was found inadmissible
from the difficulty of firing the powder at considerable depths
in the ice, and from the comparatively small masses removed by
this means. After much consideration and many trials, a mode
has been adopted and put in execution by M. Venetz, which
promises the greatest success.

M. Venetz had remarked that the glacier could not support
itself where the river was of a certain width, but fell into it, and
was dissolved; whereas, where the river was comparatively
narrow, the ice and snow formed a vault over it, and conse-
quently tended to the preservation of any portion falling from
the glacier above. Perceiving also the effect of the river in
dissolving the parts it came in contact with, he formed and exe-
cuted the design of bringing the streams of the neighbouring
mountains by a canal to Mauvoisin, opposite the highest part
of the glacier, where it touched that mountain. From hence it
was conducted, by wooden troughs, on to the glacier in a direc-
tion parallel to the valley. The water was divided into two
streams, one falling nearly onthe one edge of the Dranse, and the
other on the other; and having been warmed by the sun in its

Natural. History. 391

cotirse, soon cut very deep channels in the ice. When they
reached the river, the troughs were removed a few feet, and thus
the streams produced the effect of asaw, which, dividing the ice,
forced the portion between them to fall into the Dranse.

When the weather is fine, these streams, which are not more
than four or five inches in diameter, act with extraordinary
power, piercing a hole 200 feet deep and six feet in diameter in
24 hours. They are calculated to remove one hundred thou-
sand cubical feet of ice from the barrier daily, and it is sup-
posed that, if the weather is fine, the whole will be removed in
three years.

At the end of the season of 1822, the Dranse remained
covered only for a length of 80 toises (of six feet), whereas at
the commencement of the operation it was covered over a length
of 225 toises. M. Venetz estimates the quantity of ice, removed
in 1822, as between eleven and twelve millions of cubical feet—
Bib, Univer. xxii. 58.

14, On the Theory of Falling Stars.—M. Bellani, in a mémoire
on the meteors called falling stars, supports the theory that they
are formed by the combustion of trains of inflammable gases or
vapours in the atmosphere. He thinks that these trains may
exist in the higher regions without being dissipated, in conse-
quence of the general and perfect tranquillity which may be con-
sidered as existing there. He endeavours to combat the diffi-
culty which is generally urged to such a theory, of the diminished
inflammability of any gaseous or vaporous mixture by expansion,
by referring to the vapour of phosphorus, stating, ‘ that phos-
phorus becomes luminous, or suffers a slow combustion, at a
temperature so much the lower as the quantity of oxygen gas in
a determinate space is rendered smaller, either by mixture with
other gases, or by rarefaction;” and then ventures the con-
jecture, that there may be other substances, capable by natural
operations of being reduced into the state of vapour or gas ; and
which, though at common temperature and pressure are not
inflammable, may become so by being elevated in the atmo-
sphere.—Giornale di Fisica, vy. 195.

15. Preservation of Anatomical Preparations.—Dr. Macart-
ney, of Dublin, employs for this purpose a solution of alum and
nitre, which preserves the natural appearance of most of the
parts of the body much better than spirit of wine, or any other
liquid hitherto employed. In order to impregnate entirely ana-
tomical preparations, the liquid ought to be renewed from time
to time at first. The proportion of the two salts and the strength
of the solution should vary according to circumstances. The
solution possesses such an antiseptic power that it destroys
completely, in a few days, the foetor of the most putrid animal
substances.—Ann. de Chim., xxi. 223.

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INDEX.

AEROLITE of Epinal, analysis of, 166—316

Air, test of the dryness of, 160, On the action of flowers on,
317, 318. The resistance of the air determined from Captain
Kater’s experiments on the pendulum, 351—356

Air-gun, experiments on the light produced by the discharge of,
64—66

Alkaline Carbonates, effect of a vacuum on, 383

Almonds (bitter), experiments on the volatile oil of, 155, 156.
Notice of a crystallized deposit in the oil of, 376

Alumina, notice of native phosphate of, 168; and of the native
sulphate of iron and alumina, 389

Ammonia, muriate of, from coal strata, 169, 170. Discovered
in lava, 169. Experiments on a persulphate of iron and
ammonia, 381, 382

Ammoniacal Gas, action of, on copper, 157

Analyses of new books, 108—127; 320—348. Of a new sul-
phur spring at Harrowgate, 82—89. Of an aérolite, 106.
Of uranite, 168. Of native phosphate of alumina, 168. Of
crystallized stalactitic quartz, 169. Of the waters of Carlsbad,
170. Of different French limestones, 311—314. Of the
touchstone, 315, 316. Of an aérolite, 166, 316. Of the
fruit of the areca catechu, 317. Of native sulphate of iron
and alumina, 389

Anatomical Preparations, preservation of, 391

Animal Charcoal, action of, in the refining of sugar, 156

Annonay, notice of an economical bridge at, 136

Areca Catechu, analysis of the fruit ef, 317

Ascension (island of), barometrical measurement of the height of
the mountain-house at, 69

Astronomical and Nautical Collections, 128—135; 351—366

Atmosphere, on the ascent of clouds in, 165, 166

Attrition, the cause of the light emitted on discharging an air-
gun, 66

B

Bagne lake and glacier, account of, 390, 391
Bandana Gallery at Glasgow described, 209—216

394 INDEX.

Barium, sulphuret of, experiments on, 149

Barometers and Thermometers, variation of, 371, 372

Barometrical Measurement of the height of the sugar-loaf moun-
tain at Sierra Leone, 67—69. Of the mountain-house at
Ascension, 69. Of the Port-Royal mountains, Jamaica, 70.
Of the block-house at Fort George, Trinidad, ibid. Of the
Pico Ruivo in the island of Madeira, 75—82

Barytes, test for, 383

Berthier (M.) experiments of, on sulphurets produced from sul-
phates, 147—151. Analyses of different French limestones,
311—314

Bessel’s Theory of Refractions, remarks on, 356, 357

Bitumen, existence of, in minerals, 389

Books (Scientific), analysis of, 108—127 ; 320—348

Boracic Acid, effects of, on the acid fiuate of potash, 308

Braconnot’s (M.) account of a new green colour, 309, 310

Brain, extraordinary affection of, cured by cold, §c., 8—I11.

Brewster (Dr.), notice of a new fluid discovered by, in the
cavities of minerals, 374, 375

Bridge of the Holy Trinity at Florence, observations on the cur-
yature of the arches of, 1—8. Economical one at Annonay,
136. Observations on the taking down and rebuilding of
London Bridge, 269—278. Notice of the laying of the first
great iron-plate for the bridge at Menai Straits, 367

Buckland’s (Rey. William) Reliquie Diluviane, analysis of, with
remarks, 337—347

Busby (Mr.), notice of the hydro-parabolie mirror of, 137

Cc

Cagniarel de la Tour (Baron), experiments of on the action of
heat and pressure on certain fluids, 145—147

Calcareous Spar, formation of, 384

Calcium (sulphuret of), experiments on, 149

Carbon, new mode of obtaining the hydriodide of, 297—301

Carbonic Acid, estimation of the quantity of, in mineral waters,
158, 159

Carlsbud, analysis of the mineral waters of, 170

Cat, instance of electricity jn, 163

Charcoal (animal) action of, on lime, 384 :

Chemical Science, Miscellaneous Intelligence in, 145—164;
374—385

Chlorine, experiments on the hydrate of, 71—74. Triple
compounds of, 378. Its action on muriate of iron, §c., 378

Chromic Acid, combinations of, with potash, 310, 311

Church (Mr.) notice of his improved printing-machine, 138

Cinnabar, new process for preparing, 161

Clarification of wine, process for, 385

Clouds, on the ascent of, in the atmosphere, 165, 166

a ee

eee

INDEX. 395

Coal-gas retorts, artificial plumbago in, 159. Estimate of the
force of the explosion of, 278—282

Cold, produced by the evaporation of liquids, experiments and
observations on, 294—297

Comet, triennial, re-discovery of, 132—134. Notice of a new
comet, 168

Copper, experiment on the sulphuret of, 150. Process of re-
fining or toughening it, 156. Action of ammoniacal gas on,
157

Creation, Mosaic account of, explained, 116—118

Crum (M.) important points by, in the chemical history of In-
digo, 152—154

Crystalline Forms of artificial salts, observations on, 282—288

Curvature of the arches of the bridge of the Holy Trinity at
Florence, observations on, 1—8

Cyanogen, experiments on a crystalline matter formed in the
solution of, 302, 303

Cyanurets, production of, 381

D

Deluge, Mosaical account of, elucidated, 118—126

Density of water, maximum of, 372

Despretz (Ces.) experiments of, on the density of vapours, 297
Diabetes, singular case of, 386

Didot (M.) process of, for casting new stereotype plates, 138
Dobereiner’s apparatus for making extracts, notice of, 162
Dryness of air or gases, test of, 160

Dry-rot, experiment for preventing, 141

E

Elaine, separation of, from oils, 384

Electricity of a cat, instance of, 163. Produced by pressure,
368. Developement of, by two pieces of the same metal, 369

Electro-magnetism, new experiments in, 374

Encke’s triennial comet, re-discovery of, 132 —134

Engine-boilers, observation on the feeding of, 137, 138

Eruption of Vesuvius in October, 1822, described, 175—183

Excrements of serpents, analyses of, 319

Explosion of coal-gas, estimate of the force of, 278—282

Extracts, notice of an apparatus for, 162

F

Falling Stars, theory of, 391

Faraday (M.) experiments of, on the hydrate of chlorine, 71—
74. Condensation of gases into liquids by him, 74; 163.
Historical statement respecting electro-magnetic rotation,
288—292

Filberts, fertilization of the female blossoms of, 107

396 INDEX.

Flowers, action of, on air, 317, 318

Fluids, action of heat and pressure on, 145—147

Fresnel (M.) observations of, on the ascent of clouds in the
atmosphere, 165, 166

Fungi, notice of new species of, 172

G

Gases, new test for ascertaining the dryness of, 160. Con-
densation of them into liquids, 74; 163

Gas-Lighting in London, extent of, 367

Gay-Lussac, experiments and observations of, on the cold pro-
duced by the evaporation of liquids, 294—297

Geologies, Mineral and Mosaic, comparative estimate of, ana-
lyzed, 108—127

Gilbert (Davies, Esq.), researches on the vibrations of heavy
bodies in cycloidal and circular arches, &c., 90—103

Glaze, improved, for red earthen ware, 142

Grain, preservation of, from mice, 140

Green Colour, account of the preparation of a new one, 309,
310

Groombridge (Stephen, Esq.), empirical elements of a table of
refraction, 128—131]

Gunpowder, inflammation of, under water, 164

H

Haloes, artificial formation of, 367

Harrogate, analysis of a new sulphur spring at, 82—89

Hart (Mr. John), experiments of, on the production of light by
discharging an air-gun, 64—66

Harvey (George, Esq.), experimental inquiries relative to the
formation of mists, 455—64

Heat and pressure, action of, on certain fluids, 145—147. In-
stance of heat, produced by the friction of a solid against a
liquid, 162

Horticultural Society, proceedings of, 105—107

Humite, analysis of, 324, 325

Hydrate of chlorine, experiments on, 71—74

Hydriodide of carbon, new mode of obtaining, 297, 298—301

Hydrocyanic Acid, preparation of, 380

Hydro-parabolic Mirror, notice of, 137

Hydroxanthic Acid, preparation of, 304. Account of its pro-
ducts and combinations, 305—309

I

Indigo, some points in the chemical history of, 152—154.
Important discovery of British indigo, 140

Intelligence (Miscellaneous), in Mechanical Science, 136—144 ;

i

INDEX. 397

367—374. In Chemical Science, 145164; 374—385. In
Natural History, 165—173; 385—391.

Jodide of nitrogen, preparation of, 381

fodine, notice of a new compound of, 376—378

Tris (blue), new test colour from, 161

Tron (sheet), new process for soldering, 142. Analyses of a
per-sulphate of iron and ammonia, 381, 382. Test for the
proto-salts of iron, 882. Analysis of native sulphate of iron
and alumina, 389

K

Kirchoff (M.), new process for preparing cinnabar, 161

Koenig (Charles, Esq.), account of the rock specimens col-
lected by Captain Parry, during his northern voyage of dis-
covery, 11—22

L

Lamarck’s genera of shells, 23—52; 216—258

Lamp, notice of a new one, 143, 144

Lapis Lydius, or touchstone, analytical examination of, 315

Lassaigne, (M.) experiments of, on the compounds of nickel,
151, 152

Lead (Sulphuret of), experiment on, 150

Levy, (Mr.) observations of, on the crystalline forms of artificial
salts, 282—288

Light, evolved by pressure, 368

Lime, action of animal charcoal on, 384

Limestones, analyses of different, in France, 311—314

Liquids, on the cold produced by the evaporation of, 294—-297

London Bridge, observations on the taking down and re-
building of, 267 —278

Lunar Tables for 1819 and 1820, errors of, corrected, 131

M

Macartney, (Dr.) process of, for preserving anatomical pre-
parations, 391

Mac Culloch, (Dr.) observations on mineral veins, 183—209

Macneill, (John) observations of, on the influence of local at-
traction on, 22, 23

Magnesium (sulphuret of), experiments on, 149, 150

Manganese (sulphuret of), experiments on, 150

Meadow-Saffron, preparations of, 170

Measure, new standard of, 137

Mechanical Science, Miscellaneous Intelligence in, 136—144 ;
367 — 374

Melville Island, remarks on rock-specimens from, 18 —21

Mesotype from Vesuvius, notice of, 389

Meteor, notice of one, 167

398 INDEX.

Meteorological Diary, for December 1822, and January and
February, 1823, 174. For March, April, and May, 392

Mice, preservation of grain, Sc., from, 140

Mimosa Pudica, remarks on, 387, 388 '

Minerals, notice of a new fluid discovered in the cavities of,
375, 376. Existence of bitumen in them, 389

Mineral and Mosaical Geologies, comparative estimate of,
108—127

Mineral Veins, observations on, 183—209

Mists, experimental inquiries relative to the formation of, 55—64

Monteith and Co., (Messrs.) Great Bandana Gallery of, at
Glasgow, described, 209—216

Mortars, observations on, 314, 315

Muriate of iron, action of chlorine on, 378

N

Natural History, Miscellaneous Intelligence in, 165—173;
385—391

Needle (magnetic), on the influence of local attraction on, 22, 23

Nickel, protoxide of, 151. Deutoxide of, ebid. Sulphuret of,
ibid. Chloride and Iodide of, 152

Nitrogen, action of, in the process of respiration, 386

O

Oil of bitter almonds, experiments on, 155
Opium (English), successful culture of, 139, 140
Organic Remains, notice of, 172

r.

Parker’s patent portable static lamp, notice of, 143, 144.

Parry (Captain), account of rock specimens collected by, dur-
ing his northern voyage of discovery, 11—22.

Paste, directions for making, that will not become mouldy, 141.

Payen and Chevallier (MM.), analysis of their Traité Elemen-
taire des Réactifs, 326—337.

Peach of China, notice of, 105.

Penn (Granville), analysis of his comparative estimate of the
mineral and Mosaical geologies, 108 — 127.

Pepys (J. H.), improvement by, in the construction of voltaic
apparatus, 143.

Per-sulphate of iron and ammonia, component parts of, 381, 382.

Phillips’s (William) Elementary Introduction to the knowledge of
mineralogy, analysis of, 320—326.

Phosphate of alumina, analysis of, 168, 169.

Phosphorus, action of, on water, 383.

Pico-Ruivo, barometrical measurement of the height of, in the
island of Madeira, 75—82.

Plana’s (Mr.) researches relating to refraction, remarks on,
362—366,

INDEX. 399

Plumbago; notice of artificial, in coal-gas retorts, 159
Pond (John, Esq.), predicted and observed places of the prin-
cipal stars, 135
Port-Royal Mountains, Jamaica, barometrical measurement o
‘the height of, 70 . .
Potash, observations on the crystalline forms of the salts of,
282—288, Effects of the boracic acid on the acid fluate of
potash, 303.. Experiments on the hydroxanthate of potash,
305—307. Combinations of the chromic acid with potash,
310, 311
Potassium (Sulphuret of), experiment on, 149. On the pre-
paration of potassium, 380, 381
Potato, wild, on the native country and culture of, 259—266
Preservation of echini, asterize, crabs, &c., 172,173. Of ana-
tomical preparations, 391
Pressure and heat, action of, on certain fluids, 145—147. Elec-
tricity produced by it, 368. Light evolved by it, zbed.
Printing, improvement in, 138
Prize Question: —On the magnetism of the solar rays, 163

Q
Quartz, analysis of crystallized stalactitic, 169

R

Rain, fall of, in the tropics, 167

Red Ware, new glaze for, 142

Reflecting Telescopes; mode of protecting the specula of, 52

Refraction, empirical elements ‘ofa table of, 128—131. Re-
marks on Mr. Plana’s researches relating to refraction, 362
—366

Resistance of air, determined from Captain Kater’s experiments
on the pendulum, 351—356

Respiration, action of nitrogen in, 386

Robiquet (M.) experiments of, on the volatile oil of bitter
almonds, 155

Rock Specimens, from North America, account of, 11—22

Rotation (Electro-Magnetic), historical statement respecting,
288—292

Royal Society, proceedings of 164 ; 292, 293

Rumker (Charles) re-discovery by, of Encke’s triennial comet,
132134

Sabine (Captain), details by, of a barometrical measurement of
the sugar-loaf mountain at Sierra Leone, 67—69. Of the

mountain-house at Ascension, 69. Of the block-house at
Fort-George, Trinidad, 70. Of Port Royal mountains, Ja-

Vor. XV. 2D

400 INDEX.

maica, 70. Of the height of the Pico-Ruivo, in the island
of Madeira, 75—-82

Salts, (artificial) observations on the primitive forms of; 282
—288

Scroope {(G. P. Esq.), account of the eruption of Vesuvius, in
October, 1822, 175—183

Seebeck (M.), new experiments of, on electro-magnetic action,
374

Sensation, experienced at great altitudes, 386

Sensitive Plant, remarks on, 387, 388

Serullas (M.), on the hydriodide of carbon, and a new method of
obtaining it, 297—301

Shells, Eamarek’é Genera of, 23—-52 ; 216—258

Societies, proceedings of; the Royal Society, 104; 292, 293:
The Horticultural Society, 105—107

Sodium, (Sulphuret of) experiment on, 149. Preparation of so*
dium, 379, 380

Soldering of sheet i iron, new process for, 142

Solima territory, ceographical notice of, 171

Sonorous chords, on the oscillations of, 374, oi5

Specula of reflecting telescopes, mode of protecting, 52—54

Stars, (principal) predicted, and observed places of, 135

Stereotype plates, new process for casting, 138

Stockler’s (Mr.) Inverse method of limits, 357—360

Strontium, (sulphuret) composition of, 149. Test for stron-
tium, 383

Succinic acid, discovered in turpentine, 161

Sugar, action of animal charcoal in the refining of, 156

Sugar-loaf Mountain, Sierra Leone, barometical measurement of
the height of, 67—69

Sulphate (native) of iron and alumina, analysis of, 389.

Sulphurets produced from sulphates, experiments on, 147—151

Sulphuric-acid, on the fixedness of, 383

Sulphur-spring, analysis of a new one at Harrogate, 82—89

T

Tassaert (M.) on the combinations of chromic acid with pot-
ash, 310, 311

Tenacity of iron wire, perry instance of, 136. Remarks
on, 373; 374

Test for proto-salts of iron, 382; for barytes and strontia, 383

Thenard’s blue, preparation of, 381

T hermometers, variation of, 160; 369—371 ; 371, 372

Time of conjunction in right ascension, an easy method of comi-
puting; from an observed occultation, 360; 361

Toad, instance of one found in a solid rock, 386

Tongue, irritability of, 385

Touchstone, analytical examination of, 315, 316

INDEX. 401

Trees, the growth of, how promoted, 388
Turnips, preservation of, 141
Turpentine, succinic acid discovered in, 161

U

Uranite, analysis of, 168
Ure (Dr.) mode of protecting the specula of reflecting telescopes,

52—54
Vv

Vacuum, effect of, on alkaline carbonates, 383, 384
Vapours, experiments on the density of, 297
Variation of thermometers, 160; 369—371 ; and of barometers,

371, 372.
Vauquelin (M.) on a crystalline matter formed in a solution of

cyanogen, 302, 303. Analytical examination of touchstone
by, 315, 316. And of an aérolite, 316
Vegetation in atmospheres of different densities, experiments

on, 388
Vesuvius, account of the eruption of, in October 1822, 175 —183.

Notice of mesotype from, 389
Vibrations of heavy bodies, researches on, 90—103
Voltaic apparatus, new form of, 143

W

Ware (Samuel, Esq.) on the curvature of the arches of the
bridge of the Holy Trinity, at Florence, 1—8

Water, hydraulic, instrument for raising, 137. Change of water
at falls, 172. Maximum density of water, 372. Action of
phosphorus on water, 383

Wax, (virgin) analysis of, 384

West (Wm. Esq.) analysis by, of a new sulphur spring at Har-
rogate, 82—89

Wine, process for clarifying, 385

Y

Yeast, expeditious modes of making, 141
Yeats, (Dr.) ona cure of an affection of the brain by cold, &c.,
8—11
Z

Zeise (W. C.) experiments of, on the hydroxanthic acid, and
some of its compounds, 304—309
Zinc, (sulphuret of) experiments on, 150

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